bluuebunny/crossref_metadata_2025 huggingface dataset:
Biogeochemistry and the structure of tropical brown food webs
Authors: Kaspari Michael , Yanoviak Stephen P.
Published: December 2009

Litter invertebrates are notoriously patchy at small scales. Here we show that the abundance of 10 litter taxa also varies 100‐fold at landscape and regional scales across 26 forest stands in Peru and Panama. We contrast three hypotheses that link gradients of abundance to ecosystem biogeochemistry. Of 14 factors considered (12 chemical elements, plus fiber and litter depth), four best predicted the abundance of litter invertebrates. In the Secondary Productivity Hypothesis, phosphorus limits abundance via the conversion of detritus to microbial biomass. Two of four microbivore taxa, collembola and isopods, increased with the percentage of P (%P) of decomposing litter. However, percentage of S (correlated with %P) best predicted the abundance of collembola, oribatids, and diplopods (r2= 0.38, 0.33, 0.21, respectively). In the Structural Elements Hypotheses, N and Ca limit the abundance of silk‐spinning and calcareous taxa, respectively. Mesostigmatids, pseudoscorpions, and spiders, all known to make silk, each increased with percentage of N of litter (r2= 0.22, 0.31, 0.26, respectively). Calcareous isopods, but not diplopods, increased with percentage of Ca of litter (r2= 0.59). In the Ecosystem Size Hypothesis, top predators are limited by available space. The abundance of the three remaining predators, chilopods, staphylinids, and ants, increased with litter depth (r2= 0.31, 0.74, 0.69, respectively), and food webs from forests with deeper litter supported a higher ratio of predators to microbivores. These results suggest that biogeochemical gradients can provide a mechanism, through stoichiometry and trophic theory, shaping the geography of community structure.
Transient patterns in the assembly of vernal pool plant communities
Authors: Collinge Sharon K. , Ray Chris
Published: December 2009

Community assembly theory asserts that the contemporary composition of ecological communities may depend critically on events that occur during the formation of the community; a phenomenon termed “historical contingence.” We tested key aspects of this theory using plant communities in over 200 experimentally created vernal pools at a field site in central California, USA. The experiment was initiated in 1999 with construction of vernal pool basins into which different seeding treatments were imposed to evaluate the effects of dispersal limitation, order of colonization (“priority effects”), and frequency of colonization on plant community composition. We tracked the abundance and distribution of five focal species for seven years following seeding and observed strong but transient effects of seeding, as well as order and frequency of colonization. All five species occurred with higher frequency in seeded pools vs. unseeded control pools, demonstrating dispersal limitation. Three of four species exerted strong priority effects, with much higher abundance in pools in which they were seeded first compared to pools in which they were seeded in the second year of the study, one year after other species were seeded. We tested for effects of frequency of colonization using one species, the endangered Lasthenia conjugens, and observed much higher abundance in frequently vs. infrequently seeded pools for the first four years following seeding. Finally, we observed that the strength of priority effects varied significantly with water depth for one of the species groups, which demonstrates that abiotic context can strongly influence species interactions. We conclude that several aspects of historical contingence play key roles in the early formation of vernal pool plant communities. But we also observed reversals in community trajectories, suggesting that in this system historical effects may be lost within a decade.
Sampling rate and misidentification of Lévy and non‐Lévy movement paths
Authors: Plank Michael J. , Codling Edward A.
Published: December 2009

A large number of empirical studies have attributed Lévy search patterns to the foraging movements of animals. Typically, this is done by fitting a power‐law distribution with an exponent of 1 < μ ≤ 3 to the observed step lengths. Most studies record the animal's location at equally spaced time intervals, which are sometimes significantly longer than the natural time scale of the animal's movements. The collected data thus represent a subsample of the animal's movement. In this paper, the effect of subsampling on the observed properties of both Lévy and non‐Lévy simulated movement paths is investigated. We find that the apparent properties of the observed movement path can be sensitive to the sampling rate even though Lévy search patterns are supposedly scale‐independent. We demonstrate that, in certain contexts and dependent on the sampling rate used in observation, it is possible to misidentify a non‐Lévy movement path as being a Lévy path. We also demonstrate that a Lévy movement path can be misidentified as a non‐Lévy path, but this is dependent on the value of μ of the original simulated path, with the greatest uncertainty for μ = 2. We discuss the implications of these results in the context of studies of animal movements and foraging behavior.
Nutrient enrichment homogenizes lake benthic assemblages at local and regional scales
Authors: Donohue Ian , Jackson Andrew L. , Pusch Martin T. , Irvine Kenneth
Published: December 2009

The compositional heterogeneity of biotic assemblages among sites, or β‐diversity, regulates the relationship between local and regional species diversity across scales. Recent work has suggested that increased harshness of environmental conditions tends to reduce β‐diversity by decreasing the importance of stochastic processes in structuring assemblages. We investigated the effect of nutrient enrichment on the compositional heterogeneity of lake benthic invertebrate assemblages in Ireland at both local (within‐lake) and regional (among‐lake) scales. At local scales, we found that the compositional heterogeneity of benthic assemblages was related inversely to the extent of nutrient enrichment (as indicated by measurements of water column total phosphorus, total nitrogen, and chlorophyll a), after effects of lake morphology (i.e., surface area, connectivity, and depth of sampling) and alkalinity were accounted for. At regional scales, we found that nutrient‐rich lakes had significantly more homogenous benthic assemblages than nutrient‐poor lakes, over and above the effect of alkalinity and across a similar range of lake morphologies. These findings have profound implications for global aquatic biodiversity, as the homogenization of benthic assemblages at both local and regional scales may have important and unpredictable effects on whole aquatic ecosystems, with potentially considerable ecological and evolutionary consequences.
Comment on Richardson: The Truth about Redistribution
Authors: Hendricks Wallace
Published: December 2009

Look to the way the Constitution allocates Senate seats to understand the truth about redistribution, says Wallace Hendricks of the University of Illinois.
Ecology and distribution of an invasive species Aster­lanceolatus willd. on wet habitats in Belgrade
Authors: Obratov-Petkovic Dragica , Bjedov Ivana , Radulovic Stojanka , Skocajic Dragana , Djunisijevic-Bojovic Danijela , Djukic Matilda
Published: December 2009

The species Aster lanceolatus occupies a significant position in the world and European lists of invasive species. Its spreading potential is a hazardous factor to the biodiversity in many countries. There are no relevant data on the wider proportion of this species in the area of Belgrade. The sites of Aster lanceolatus are annual or pioneer communities along the water courses, abandoned and neglected areas, forest margins, moist meadows. The study areas are located near a choice of water courses in Belgrade. The aim of the study was to assess the species ecology and population density, synecological interrelationships among the coenobionts of the communities in which it occurs, and also to map its the habitats. The study of population density was performed on the supplemented and partially modified 'CPS SKEW' form, applied in West European countries, by the principle of squares. The species was determined by standard floristic method, and the species location by GPS system. It was concluded that Aster lanceolatus was dominant and wild at all study sites. The individuals and populations are especially numerous on the river islands Ada Ciganlija and Veliko Ratno Ostrvo, along the stream Kumodrsaki Potok and the Danube left bank, where the number of individuals per squares is above 1300 and the degree of coverage is 100%. Its spreading potential is conditioned by the species biology, and the expansiveness by climate changes, anthropogenic impacts and the competitive interrelationships.
Ancient metallurgical traditions and connections around the caput Adriae
Authors: Giumlia-Mair A.
Published: December 2009

In the last decade several archaeological projects concerning metallurgical tradition and techniques, were carried out on metal finds from various sites around the Northern Adriatic and in the Eastern Alps. The pieces, made of different metals, are dated to various periods, between the Late Bronze Age and Late Antiquity. The results of different kinds of analytical techniques, applied to several hundreds of archaeological metal artefacts from this area, are presented and evaluated in the paper. The different metallurgical techniques and traditions, identified during the researches are illustrated, compared and interpreted. An overview of the available data and of the general trends of ancient metallurgy in this broader area is attempted.
Prehistoric copper tools from the territory of Serbia
Authors: Antonovic D.
Published: December 2009

Around four hundreds prehistoric copper tools and weapons have been recorded in the territory of Serbia so far. They had been in use for a rather long period of time - from the end of the early phase of the Vinca culture until the Middle Bronze Age and some types of these objects even until the very beginning of the Iron Age. The copper alloyed with small quantities of arsenic, lead and tin started to appear already by the end of the Eneolithic indicating the attempts of prehistoric metallurgist to improve technical characteristics of the copper. On the copper tools from the territory of Serbia could be followed the evolution of shapes starting from the specimens, which completely imitated stone tools and which appeared in the beginning of the Early Eneolithic to the completely developed Bronze Age shapes, which confirm that prehistoric metallurgist entirely understood and accepted the advantages offered by metalworking. The analyses of metal composition have been performed on around 50% of prehistoric copper tools. Nevertheless, in spite of all relatively numerous analyses there is still no answer to the question concerning the primitive technology of copper ore processing and the metallurgical process of obtaining copper for the production of copper and sometime later the bronze artifacts.
Synthesis and characterization of selected fused isoxazole and pyrazole derivatives and their antimicrobial activity
Authors: Dabholkar Vijay , Ansari Faisal
Published: December 2009

New potent antibacterials, fused isoxazole and pyrazole derivatives, were synthesized using 5,5-dimethylcyclohexane-1,3-dione (1) and 3-[(4-chlorobenzylidene) amino]-2-thioxoimidazolidin-4-one (2) as synthons. Aromatic aldehydes on condensation with 1 and 2 gave 2-arylidene-5,5-dimethylcyclohexane- 1,3-dione (3) and 5-arylidene-3-[(4-chlorobenzylidene)amino]-2-thioxoimidazolidin-4-one (4), respectively. Compounds 3 and 4 were forced to undergo heterocyclization reaction with nucleophilic reagents to give the title compounds. The newly synthesized heterocyles (5-8) were characterized based on their chemical properties and spectroscopic data, and were found to inhibit Staphylococcus aureus and Corynebacterium diphtheriae.
Effect of solution treatment conditions on the sensitization of austenitic stainless steel
Authors: Yu Xiaofei , Chen Shenhao , Wang Liang
Published: December 2009

In this study, the impact of the conditions of solution treatment on the degree of sensitization (DOS) of austenitic stainless steel (AISI 304) was investigated in detail. The results derived from the electrochemical potentiodynamic reactivation (EPR) test indicated that the DOS decreased as the solution treatment temperature and time increased. The reason for this was studied via the SEM morphologies and EDS results, which indicated that the grain size influenced the DOS. Furthermore, cellular automaton (CA) was utilized to simulate grain growth, the precipitation of Cr-rich carbides and the three dimensional distribution of the chromium concentration, which vividly illuminated the effect of the grain size on the DOS and was in accordance with the experiment results.
Synthesis and Biological Activity of Novel 1-(Substituted Phenoxyacetoxy) Alkyl Phosphonates and Phosphinates
Authors: Meng Liping , Joshi Rajendra , Li Meiqiang , He Hongwu
Published: December 2009

To investigate the influence of nitro group on the biological activity of phenoxyacetoxy phosphonates and phosphinates, a series of novel 1-(substituted phenoxyacetoxy) alkyl phosphonates and phosphinates were synthesized and screened for herbicidal activity and plant growth regulatory activity. Compounds 5a, 5b and 5j exhibited notable bioactivity. Results indicated that nitro groups had a  great influence on the biological activity, and the improvement of biological activity required a reasonable combination of a nitro group and other substituents. DOI: 10.3126/jncs.v23i0.2092J. Nepal Chem. Soc., Vol. 23, 2008/2009 Page: 11-20
The Study of Salt Induced Viscoelastic Wormlike Micelles in Aqueous Systems of Mixed Anionic/Nonionic Surfactants
Authors: Shrestha Rekha Goswami , Aramaki Kenji
Published: December 2009

Formation of viscoelastic wormlike micelles in aqueous systems of mixed amino acid based anionic and nonionic surfactants in presence of salt is presented. N-dodecylglutamic acid (LAD) upon neutralization with L-Lysine in 1:2 mole ratio forms globular type of micelles above critical micelle concentration and the solution follows Newtonian fluid like behavior at 25ºC. The addition of tri(oxyethylene) nmonotetradecyl ether (C14EO3) to the semi-dilute aqueous solution of the LADLysine-2 induces one dimensional micellar growth and viscosity of solution increases. After a certain concentration of C14EO3 micelles get entangled and form a rigid network of wormlike micelles and viscosity increases by several orders of magnitude. The wormlike micellar solutions show a viscoelastic character and can be described the Maxwell mechanical model with a single stress relaxation. Rheological measurements have shown that zero shear viscosity (No) increases with the C14EO3 concentration gradually at first sharpl, and then finally decreases before phase separation.Keywords: nonionic surfactant, wormlike micelles, rheology, viscoelastic solutionsDOI: 10.3126/jncs.v23i0.2098J. Nepal Chem. Soc., Vol. 23, 2008/2009 Page: 65-73
The Study of Lead Pollution in Street Dust and Drinking Water Along Arniko Rajmarg of Nepal
Authors: Shrestha Reena Amatya , Kafle Babi Kumar
Published: December 2009

Lead in street dust and drinking water along Arniko Rajmarg (ARM) of Nepal was analyzed. The concentration of lead is found high in the samples those were collected before monsoon and from heavy traffic regions.Keyword: lead, street dust, highways.DOI: 10.3126/jncs.v23i0.2105Journal of Nepal Chemical Society, Vol. 23, 2008/2009 Page: 106-108
Microsatellite primers in the white proteas (Protea section Exsertae, Proteaceae), a rapidly radiating lineage
Authors: Prunier Rachel , Latimer Andrew
Published: December 2009

• Premise of the study: Microsatellite primers were developed in the South African sclerophyllous shrub Protea punctata to investigate the degree of population differentiation within and between P. punctata and closely related species.

• Methods and Results: 10 primer pairs were identified from three individuals of Protea punctata. The primers amplified di‐ and tri‐nucleotide repeats. Across all P. punctata samples, the loci have 8–49 alleles. All primers also amplified in Protea section Exsertae (P. aurea, P. aurea subsp. potbergensis, P. mundii, P. venusta, P. lacticolor, and P. subvestita). The loci had 14–69 alleles across the subgenus.

• Conclusions: These results show the broad utility of microsatellite loci for future studies of population genetics in the white proteas and their potential utility across the entire genus.
Study in Neotropical Apocynaceae XXXIX: review of Apocynoideae and Rauvolfioideae from Honduras
Authors: Morales J. Francisco
Published: December 2009

A treatment of the subfamilies Apocynoideae and Rauvol - fioideae (Apocynaceae) in Honduras, is presented. A total of 55 species in 30 genera (Allamanda, Allomarkgrafia, Anechites, Aspidosperma, Beaumontia, Carissa, Cascabela, Catharanthus, Echites, Fernaldia, Forsteronia, Lacmellea, Macropharynx, Malouetia, Mandevilla, Mesechites, Nerium, Odontadenia, Pentalinon, Plumeria, Prestonia, Rauvolfia, Rhabdadenia, Stemmadenia, Tabernaemontana, Thenardia, Thevetia, Tintinnabularia, Tonduzia, Vallesia) are treated. Echites, Mandevilla, Prestonia, and Tabernaemontana are the most representative genera. Descriptions, keys, data on ecology, distribution, phenology, common names as well as lists of specimens examined are provided. Photographs are provided for the majority of species. The presence in Honduras of Allomarkgrafia plumeriiflora, Anechites nerium, Macropharynx renteriae, Stemmadenia eubracteata and Thenardia chiapensis is reported here for the first time.
THE EFFECTS OF MORPHOLOGY STRUCTURE FOR COPPER PHTHALOCYANINE SENSORS DETECT TO ORGANIC ACID
Authors: Hsieh Jin-Chi
Published: December 2009

The copper phthalocyanine ( CuPc ) thin film gas sensors detect to organic acids that its detection behaviors will be affected morphology with quartz crystal microbalance (QCM) method. The amorphous structure has looser surface and finer particles; therefore, it has smaller surface area. Although it has more active sites to adsorb acid molecular, it gets smaller value of frequency change (Δf) than α-phase morphology. The β-phase morphology has the largest surface area, so it gets the smallest value of Δf. The response behavior is more rapid than recovery behavior with any morphology CuPc thin film gas sensors. The film surface of amorphous structure has more porous, it has faster response time and recovery time than other structures. The β-phase morphology can get slowest response and recovery time. The results show that the CuPc thin film gas sensors detect to organic acid behavior, for example methyl acid and ethyl acid, etc.; it was affected to its surface morphology change.
CD40 Ligand-Induced Carcinoma Cell Death: A Balance between Activation of TNFR-Associated Factor (TRAF) 3-Dependent Death Signals and Suppression of TRAF6-Dependent Survival Signals
Authors: Elmetwali Taha , Young Lawrence S. , Palmer Daniel H.
Published: December 2009

The effects of CD40 ligation in an epithelial context are complex, with the level of CD40 engagement influencing the physiological outcome. Low levels of CD40 ligation promote cell survival/proliferation, whereas high levels induce growth arrest/apoptosis. The precise form of the CD40 stimulus affects these responses with the most profound effects in carcinoma cells being induced by membrane-bound rather than recombinant soluble CD40L. However, the signaling pathways underlying these differential responses are yet to be fully characterized. We have investigated the mechanistic differences resulting from CD40 engagement by soluble and membrane-bound ligands using a novel adenovirus-delivered CD40L mutated to resist cleavage from the cell membrane in the CD40-positive EJ bladder carcinoma cell line. We have shown that membrane-bound CD40L induces apoptosis by influencing the balance between apoptotic and survival signals. Thus, membrane-bound CD40L stabilizes TNFR-associated factor 3 to induce JNK-dependent apoptosis via release of mitochondrial cytochrome c, caspase 9, and effector caspases 3/7. Further, we have shown that this process is dependent on activation of caspase 8. However, there is also a requirement for suppression of TNFR-associated factor 6-mediated PI3K/Akt-dependent survival signals for apoptosis to occur. These data provide mechanistic insights into the consequences of CD40 activation in carcinoma cells and how these might be exploited in the clinical development of CD40-targeted anticancer therapies.
Listeria monocytogenes-Infected Human Peripheral Blood Mononuclear Cells Produce IL-1β, Depending on Listeriolysin O and NLRP3
Authors: Meixenberger Karolin , Pache Florence , Eitel Julia , Schmeck Bernd , Hippenstiel Stefan , Slevogt Hortense , N’Guessan Philippe , Witzenrath Martin , Netea Mihai G. , Chakraborty Trinad , Suttorp Norbert , Opitz Bastian
Published: December 2009

Different NOD-like receptors, including NLRP1, NLRP3, and NLRC4, as well as the recently identified HIN-200 protein, AIM2, form multiprotein complexes called inflammasomes, which mediate caspase-1–dependent processing of pro-IL-1β. Listeria monocytogenes is an intracellular pathogen that is actively phagocytosed by monocytes/macrophages and subsequently escapes from the phagosome into the host cell cytosol, depending on its pore-forming toxin listeriolysin O (LLO). In this study, we demonstrate that human PBMCs produced mature IL-1β when infected with wild-type L. monocytogenes or when treated with purified LLO. L. monocytogenes mutants lacking LLO or expressing a noncytolytic LLO as well as the avirulent Listeria innocua induced strongly impaired IL-1β production. RNA interference and inhibitor experiments in human PBMCs as well as experiments in Nlrp3 and Rip2 knockout bone marrow-derived macrophages demonstrated that the Listeria-induced IL-1β release was dependent on ASC, caspase-1, and NLRP3, whereas NOD2, Rip2, NLRP1, NLRP6, NLRP12, NLRC4, and AIM2 appeared to be dispensable. We found that L. monocytogenes-induced IL-1β production was largely dependent on phagosomal acidification and cathepsin B release, whereas purified LLO activated an IL-1β production independently of these mechanisms. Our results indicate that L. monocytogenes-infected human PBMCs produced IL-1β, largely depending on an LLO-mediated phagosomal rupture and cathepsin B release, which is sensed by Nlrp3. In addition, an LLO-dependent but cathepsin B-independent NLRP3 activation might contribute to some extent to the IL-1β production in L. monocytogenes-infected cells.
CD137 Promotes Proliferation and Survival of Human B Cells
Authors: Zhang Xiaoyu , Voskens Caroline J. , Sallin Michelle , Maniar Amudhan , Montes Carolina L. , Zhang Yue , Lin Wei , Li Guoyan , Burch Erin , Tan Ming , Hertzano Ronna , Chapoval Andrei I. , Tamada Koji , Gastman Brian R. , Schulze Dan H. , Strome Scott E.
Published: December 2009

CD137 (4-1BB)-mediated costimulation plays an important role in directing the fate of Ag-stimulated T cells and NK cells, yet the role of CD137 in mediating B cell function is unknown. We found that CD137 is expressed in vitro on anti-Ig–stimulated peripheral blood B cells and in vivo on tonsillar B cells with an activated phenotype. In vitro CD137 expression is enhanced by CD40 stimulation and IFN-γ and is inhibited by IL-4, -10, and -21. The expression of CD137 on activated human B cells is functionally relevant because engagement with its ligand at the time of activation stimulates B cell proliferation, enhances B cell survival, and induces secretion of TNF-α and -β. Our study suggests that CD137 costimulation may play a role in defining the fate of Ag-stimulated human B cells.
CD8 T Cell-Initiated Vascular Endothelial Growth Factor Expression Promotes Central Nervous System Vascular Permeability under Neuroinflammatory Conditions
Authors: Suidan Georgette L. , Dickerson Jonathan W. , Chen Yi , McDole Jeremiah R. , Tripathi Pulak , Pirko Istvan , Seroogy Kim B. , Johnson Aaron J.
Published: December 2009

Dysregulation of the blood-brain barrier (BBB) is a hallmark feature of numerous neurologic disorders as diverse as multiple sclerosis, stroke, epilepsy, viral hemorrhagic fevers, cerebral malaria, and acute hemorrhagic leukoencephalitis. CD8 T cells are one immune cell type that have been implicated in promoting vascular permeability in these conditions. Our laboratory has created a murine model of CD8 T cell-mediated CNS vascular permeability using a variation of the Theiler’s murine encephalomyelitis virus system traditionally used to study multiple sclerosis. Previously, we demonstrated that CD8 T cells have the capacity to initiate astrocyte activation, cerebral endothelial cell tight junction protein alterations and CNS vascular permeability through a perforin-dependent process. To address the downstream mechanism by which CD8 T cells promote BBB dysregulation, in this study, we assess the role of vascular endothelial growth factor (VEGF) expression in this model. We demonstrate that neuronal expression of VEGF is significantly upregulated prior to, and coinciding with, CNS vascular permeability. Phosphorylation of fetal liver kinase-1 is significantly increased early in this process indicating activation of this receptor. Specific inhibition of neuropilin-1 significantly reduced CNS vascular permeability and fetal liver kinase-1 activation, and preserved levels of the cerebral endothelial cell tight junction protein occludin. Our data demonstrate that CD8 T cells initiate neuronal expression of VEGF in the CNS under neuroinflammatory conditions, and that VEGF may be a viable therapeutic target in neurologic disease characterized by inflammation-induced BBB disruption.
Cutting Edge: Plasmacytoid Dendritic Cells Induce IL-10 Production in T Cells via the Delta-Like-4/Notch Axis
Authors: Kassner Nadine , Krueger Manuela , Yagita Hideo , Dzionek Andrzej , Hutloff Andreas , Kroczek Richard , Scheffold Alexander , Rutz Sascha
Published: December 2009

Proinflammatory Th1 cells can produce large amounts of the immunosuppressive cytokine IL-10, thereby facilitating the self-limitation of inflammatory responses. Recently, we identified the Notch pathway as a main regulator of IL-10 production by Th1 cells. In this study, we show that plasmacytoid dendritic cells (pDCs), by means of their unique high-level expression of the Notch ligand Delta-like (Dll)-4, activate the Notch receptor on T cells to induce robust IL-10 production in vitro and in vivo. pDCs display a distinct pattern of Notch ligands compared with conventional dendritic cells, marked by the constitutive expression of Dll-4, the only Notch ligand to induce IL-10 expression in vivo, and Dll-1, while at the same time lacking the expression of Jagged. We provide a new mechanism for IL-10 induction by pDCs underlining the importance of the Dll-4/Notch axis in the regulation of inflammatory T cell responses.
Enhancing glycoprotein sialylation by targeted gene silencing in mammalian cells
Authors: Zhang Min , Koskie Kerry , Ross James S. , Kayser Kevin J. , Caple Matthew V.
Published: December 2009

Recombinant glycoproteins produced by mammalian cells represent an important category of therapeutic pharmaceuticals used in human health care. Of the numerous sugars moieties found in glycoproteins, the terminal sialic acid is considered particularly important. Sialic acid has been found to influence the solubility, thermal stability, resistance to protease attack, antigenicity, and specific activity of various glycoproteins. In mammalian cells, it is often desirable to maximize the final sialic acid content of a glycoprotein to ensure its quality and consistency as an effective pharmaceutical. In this study, CHO cells overexpressing recombinant human interferon gamma (hIFNγ) were treated using short interfering RNA (siRNA) and short‐hairpin RNA (shRNA) to reduce expression of two newly identified sialidase genes, Neu1 and Neu3. By knocking down expression of Neu3 we achieved a 98% reduction in sialidase function in CHO cells. The recombinant hIFNγ was examined for sialic acid content that was found to be increased 33% and 26% respectively with samples from cell stationary phase and death phase as compared to control. Here, we demonstrate an effective targeted gene silencing strategy to enhance protein sialylation using RNA interference (RNAi) technology. Biotechnol. Bioeng. 2010;105: 1094–1105. © 2009 Wiley Periodicals, Inc.
Effect of cell lysates on retroviral transduction efficiency of cells in suspension culture
Authors: Beauchesne Pascal R. , Bruce Katherine J. , Bowen Bruce D. , Piret James M.
Published: December 2009

Recombinant retroviruses are effective vectors able to integrate transgenes into the target cell's genome to achieve longer‐term expression. This study investigates the effect of cell lysis products, a common cell culture by‐product, on the transduction of suspension cells by gammaretroviral vectors. Cell lysates derived from human and murine suspension cell lines significantly increased the transduction of human TF‐1 and K‐562 cell lines by gibbon ape leukemia virus‐pseudotyped retroviral vectors without altering tropism. The transduction efficiency of TF‐1 cells increased as a function of lysate concentration and decreased with increasing target cell concentrations. This was adequately predicted using a saturation equation based on the lysed‐to‐target cell concentration ratio, R, where:

Lysate completely masked the effects of fibronectin when the two were added in combination. With protamine sulfate, the transduction efficiency was increased by lysate to 58% from 20% for protamine sulfate alone. Overall, the presence of cell lysate significantly influenced the outcome of the transduction process, either alone or in the presence of protamine sulfate or fibronectin. Biotechnol. Bioeng. 2010;105: 1168–1177. © 2009 Wiley Periodicals, Inc.
Micropatterning contractile C2C12 myotubes embedded in a fibrin gel
Authors: Nagamine Kuniaki , Kawashima Takeaki , Ishibashi Takeshi , Kaji Hirokazu , Kanzaki Makoto , Nishizawa Matsuhiko
Published: December 2009

Contractile C2C12 myotube line patterns embedded in a fibrin gel have been developed to afford a physiologically relevant and stable bioassay system. The C2C12 myotube/fibrin gel system was prepared by transferring a myotube monolayer from a glass substrate to a fibrin gel while retaining the original line patterns of myotubes. To endow the myotubes with contractile activity, a series of electrical pulses was applied through a pair of carbon electrodes placed at either side of a fibrin gel separately. The frequency and magnitude of myotube contraction were functions of the pulse frequency and duration, respectively. We found that the myotubes supported by an elastic fibrin gel maintained their line patterns and contractile activities for a longer period of time (1 week) than myotubes adhered on a conventional culture dish. Biotechnol. Bioeng. 2010;105: 1161–1167. © 2009 Wiley Periodicals, Inc.
Sensitive and selective detection of mycoplasma in cell culture samples using cantilever sensors
Authors: Xu Sen , Sharma Harsh , Mutharasan Raj
Published: December 2009

In this article we report a new biosensor‐based method that is more sensitive and rapid than the current approach for detecting mycoplasma in cell culture samples. Piezoelectric‐excited millimeter‐sized cantilever (PEMC) sensors respond to mass change via resonant frequency change. They are sensitive at femtogram level and can be used directly in liquid for label‐free detection. Common cell culture contaminant, Acholeplasma laidlawii was detected in both buffer and cell culture medium. Two different sources (positive control from a commercial kit and ATCC 23206) were analyzed using antibody‐immobilized PEMC sensor. Resonant frequency decrease caused by binding of A. laidlawii was monitored in real‐time using an impedance analyzer. Positive detection was confirmed by a second antibody binding. The limit of detection (LOD) was lower than 103 CFU/mL in cell culture medium using PEMC sensor while parallel ELISA assays showed LOD as 107 CFU/mL. This study shows that PEMC sensor can be used for sensitive and rapid mycoplasma detection in cell culture samples. Biotechnol. Bioeng. 2010;105: 1069–1077. © 2009 Wiley Periodicals, Inc.
Seasonal contribution and interannual variation of evapotranspiration over a reed marsh (Phragmites australis) in Northeast China from 3‐year eddy covariance data
Authors: Zhou Li , Zhou Guangsheng , Liu Shuhua , Sui Xinghua
Published: December 2009

At present, one of unresolved critical issues relating to climate change is whether evapotranspiration (ET) is increasing or decreasing with global warming. There has been great interest, therefore, in studying ET in a variety of ecosystems to better understand the nature of the controlling interactions and the links between ET and other ecosystem processes. Especially, relatively few studies on ET have been conducted in wetland environments. In this paper, we present the results from 3 years (2005–2007) of direct ET measurements, using eddy covariance method, over a reed (Phragmites australis) marsh in Liaohe Delta, Northeast China. The seasonal and interannual variation of daily ET and its main controls were analysed. Annual ET for the reed marsh was 432, 480, and 445 mm in 2005, 2006 and 2007, respectively. The contribution of ET during non‐growing season was not negligible; it ranged from 13% to 16% of the annual ET for the investigated years. On annual course, ET increased associating with increasing temperature and reed plant growth in late‐April and early‐May, and peaked in the rapid growing season with weekly mean rates of 3·7 mm day−1 (2005), 3·7 mm day−1 (2006), and 3·4 mm day−1 (2007). Decoupling factor (Ω) also varied seasonally, with its minimum values occurred in the non‐growing season and the maximum values in the rapid growing season, especially in July. During the rapid growing season, the values of decoupling factor (Ω) were generally between 0·5 and 0·8, indicating that solar radiation was main factor affecting ET other than vapour pressure deficit (VPD). Moreover, biological factor and canopy conduction also controlled the interannual ET variation in the reed marsh. The results would be helpful to better understand ET for this particular reed marsh. Copyright © 2009 John Wiley & Sons, Ltd.
Molecular Dynamic Simulations of the Collision between Copper Ions, SF6 Molecules and a Polyethylene Surface: A Study of Decomposition Products and an Evaluation of the Self‐Diffusion Coefficients
Authors: Duffour Emmanuel
Published: December 2009

Molecular dynamics simulations are used to study the interaction between incident copper ions, SF6 molecules and a polyethylene surface. Average particle velocities from 15 to 21 km · s−1 are tested in steps of 2 km · s−1. The damage to the polyethylene crystal is reviewed in terms of material heating, local molecular disorder and bond breaking accompanied by particle emissions. Two types of emitted particles are distinguished to explain the degradation of the polymer. The first corresponds to free radicals with molecular formula CnH2n+1 and the second takes into account all other possible molecules, especially hydrogen atoms and carbonaceous molecules. The formation of CuF molecules during the interaction is shown and this result is discussed on the basis of other theoretical results concerning the calculations of plasma composition. The self‐diffusion coefficients of the emitted atoms are calculated by using two different methods: the alternative Green‐Kubo expression, based on the integrated velocity autocorrelation function, and the Einstein expression, based on the mean‐square displacement autocorrelation function.

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BDNF levels are not related with levodopa‐induced dyskinesias in MPTP monkeys
Authors: Samadi Pershia , Morissette Marc , Lévesque Daniel , Di Paolo Thérèse
Published: December 2009

Levodopa‐induced dyskinesias (LIDs) are frequent in parkinsonian patients and may result from an aberrant plasticity. Brain‐derived neurotrophic factor (BDNF) represents a likely candidate to subserve neuroadaptive processes encountered in LIDs. We compared striatal BDNF levels measured by ELISA in levodopa‐treated 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine (MPTP) monkeys having developed LIDs compared with animals where LIDs were prevented by the addition of CI‐1041 (NR1A/2B NMDA receptor antagonist) or low doses of cabergoline (dopamine D2 receptor agonist). We observed reduced striatal BDNF concentrations in levodopa‐treated MPTP monkeys with or without LIDs, suggesting that levodopa treatment is associated with reduced striatal BDNF levels and is independent of dyskinesias. © 2009 Movement Disorder Society
Myopathy causing camptocormia in idiopathic Parkinson's disease: A multidisciplinary approach
Authors: Spuler Simone , Krug Henriette , Klein Christine , Medialdea Isabel Chaure , Jakob Wibke , Ebersbach Georg , Gruber Doreen , Hoffmann Karl‐Titus , Trottenberg Thomas , Kupsch Andreas
Published: December 2009

Extreme forward flexion of the spine, named camptocormia (CC), and head drop syndrome (HD) may be among the most disabling symptoms in Parkinson's disease (PD). This study aims to eludicate the etiology of PD‐associated CC and HD via a multidisciplinary approach (clinical examination, electromyography, MRI, genetic analysis, muscle morphology) centering on the histology of the paraspinal muscles. We studied 17 patients with the clinical diagnosis of PD and CC or head drop syndrome and six controls. We performed muscle biopsies of paraspinal muscles and deep neck extensor muscles. Mean age at onset of postural abnormality was 66 years and mean latency between onset of parkinsonian symptoms to first signs of CC or head drop was 7 years. The electromyogram of paraspinal muscles was abnormal in 13–14 patients. Histopathology revealed chronic myopathic changes in 14 of 17 biopsies, consisting of abnormal variation in fiber size, increase in internal nuclei, and increase in connective tissue, myofibrillar disarray and similarities to protein surplus myopathies. Interestingly, heterozygous variants in the Parkin gene were found in 2 of 9 investigated patients. We conclude that CC and HD in PD are predominantly myopathic. Aberrant protein aggregation may link PD and CC. © 2009 Movement Disorder Society
Inter‐ and intrasubband spectroscopy of cubic AlN/GaN superlattices grown by molecular beam epitaxy on 3C‐SiC
Authors: Mietze C. , DeCuir E. A. , Manasreh M. O. , Lischka K. , As D. J.
Published: December 2009

We report the growth of cubic GaN/AlN multi quantum well (MQW) structures by plasma‐assisted molecular beam epitaxy on 10 μm thick 3C‐SiC on top of 300 μm silicon. The samples consist of 115 nm thick GaN buffer and 20 periods of GaN/AlN active regions. The thickness of the AlN barrier is 1.48 nm for all samples, while the thickness of the GaN quantum wells varies between 1.36 nm‐2.94 nm. The growth was observed by in‐situ reflection high energy electron diffraction (RHEED). The structural properties of our samples were studied by high resolution x‐ray diffraction (HRXRD). Several peaks in the HRXRD spectra reveal a high structural perfection of the MQW region. Clear evidence for inter‐ and intrasubband transitions was observed in photoluminescence (PL) and infrared absorbance spectra measured at temperatures between 2 K and 300 K. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Identity status change during adolescence and young adulthood: A meta‐analysis
Authors: Kroger Jane , Martinussen Monica , Marcia James E.
Published: December 2009

The present study was designed to examine developmental patterns of identity status change during adolescence and young adulthood through meta‐analysis. Some 124 studies appearing in PsycINFO, ERIC, Sociological Abstracts, and Dissertation Abstracts International between 1966 and 2005 provided data. All calculations were performed using the software program, Comprehensive Meta‐analysis. Results from longitudinal studies showed the mean proportion of adolescents making progressive identity status changes was .36, compared with .15 who made regressive changes and .49 who remained stable. Cross‐sectional studies showed the mean proportion of moratoriums rising steadily to age 19 years and declining thereafter, while the mean proportion of the identity achieved rose over late adolescence and young adulthood; foreclosure and diffusion statuses declined over the high school years, but fluctuated throughout late adolescence and young adulthood. Meta‐analyses showed that large mean proportions of samples were not identity achieved by young adulthood. Possible reasons for this phenomenon are explored.
My older sibling was drunk – Younger siblings' drunkenness in relation to parental monitoring and the parent–adolescent relationship
Authors: Gossrau‐Breen Diana , Kuntsche Emmanuel , Gmel Gerhard
Published: December 2009

This study explored the links between having older siblings who get drunk, satisfaction with the parent–adolescent relationship, parental monitoring, and adolescents' risky drinking. Regression models were conducted based on a national representative sample of 3725 8th to 10th graders in Switzerland (mean age 15.0, SD = .93) who indicated having older siblings. Results showed that both parental factors and older siblings' drinking behaviour shape younger siblings' frequency of risky drinking. Parental monitoring showed a linear dose–response relationship, and siblings' influence had an additive effect. There was a non‐linear interaction effect between parent–adolescent relationship and older sibling's drunkenness. The findings suggest that, apart from avoiding an increasingly unsatisfactory relationship with their children, parental monitoring appears to be important in preventing risky drinking by their younger children, even if the older sibling drinks in such a way. However, a satisfying relationship with parents does not seem to be sufficient to counterbalance older siblings' influence.
Rehabilitation Team Disagreement: Guidelines for Resolution
Authors: Savage Teresa A. , Parson John , Zollman Felise , Kirschner Kristi L.
Published: December 2009

Rehabilitation care is provided by interdisciplinary teams including physicians, nurses, therapists, social workers, psychologists, and others. When there is disagreement or miscommunication among team members, progress toward patient goals can be thwarted. This paper will discuss differing models by which teams function, and what happens when a nonphysician member of the team disagrees with the plan of care. An analysis of the ethical issues embedded in two cases will be presented, and suggestions for resolution of team disagreement will be recommended.
Circulating Chemokine Levels in Febrile Infants With Serious Bacterial Infections
Authors: Chen Hsiu‐Lin , Hung Chih‐Hsing , Tseng Hsing‐I , Yang Rei‐Cheng
Published: December 2009

Early diagnosis of serious bacterial infections (SBI) in febrile young infants based on clinical symptoms and signs is difficult. This study aimed to evaluate the diagnostic values of circulating chemokines and C‐reactive protein (CRP) levels in febrile young infants < 3 months of age with suspected SBI. We enrolled 43 febrile young infants < 3 months of age with clinically suspected SBI who were admitted to the neonatal intensive care unit or complete nursing unit of the pediatric department of Kaohsiung Medical University Hospital between December 2006 and July 2007. Blood was drawn from the patients at admission, and complete blood counts, plasma levels of CRP, granulocyte colony‐stimulating factor (G‐CSF), and chemokines, including interleukin‐8 (IL‐8), macrophage inflammatory protein‐1α, macrophage inflammatory protein‐1β, monokine induced by interferon‐γ, and monocyte chemotactic protein‐1 were measured. Patients’ symptoms and signs, length of hospital stay, main diagnosis, and results of routine blood tests and microbiological culture results were recorded. Twenty‐six infants (60.5%) were diagnosed with SBI, while 17 (39.5%) had no evidence of SBI based on the results of bacterial cultures. CRP, IL‐8 and G‐CSF levels were significantly higher in the infants with SBI than in those without SBI. Plasma levels of other chemokines were not significantly different between the groups. The area under the receiver‐operating characteristic (ROC) curve for differentiating between the presence and absence of SBI was 0.79 for CRP level. Diagnostic accuracy was further improved by combining CRP and IL‐8, when the area under the ROC curve increased to 0.91. CRP levels were superior to IL‐8 and G‐CSF levels for predicting SBI in febrile infants at initial survey. IL‐8 levels could be used as an additional diagnostic tool in the initial evaluation of febrile young infants, allowing clinicians to treat these patients more appropriately.
Expression of Signal Transducer and Activator of Transcription 3 and Suppressor of Cytokine Signaling 3 in Urothelial Carcinoma
Authors: Huang Wan‐Ting , Yang Sheau‐Fang , Wu Chun‐Chieh , Chen Wan‐Tzu , Huang Ya‐Chun , Su Yue‐Chiu , Chai Chee‐Yin
Published: December 2009

In this study, we investigated the expression of phosphorylated signal transducer and activator of transcription 3 (p‐STAT3) Tyr705 and suppressor of cytokine signaling 3 (SOCS3) in urothelial carcinoma (UC). p‐STAT3 (Tyr705) and SOCS3 were analyzed by immunohistochemistry using tissue microarray and Western blotting. Our results showed that p‐STAT3 (Tyr705) was frequently detected in high‐grade and infiltrating UC. However, there was no difference in p‐STAT3 (Tyr705) staining between UC of the upper and lower urinary tracts. In addition, there was no significant correlation between expression of SOCS3 and histological differentiation and invasiveness of UC. These findings suggest that overexpression of p‐STAT3 (Tyr705) occurs in UC, and that pathways other than SOCS3 may contribute to its activation in this cancer.
Sex Differences in Metabolic Morbidities: Influenced by Diet or Exercise Habits?
Authors: Chiu Yu‐Wen , Huang Chia‐Tsuan , Chuang Hung‐Yi , Chang Yu‐Tsz , Wu Ming‐Tsang , Liu Hong‐Wen
Published: December 2009

We implemented a nationwide population‐based study in Taiwan to compare the physical and biochemical parameters, diet and exercise lifestyles, and prevalences of diabetes, hyperlipidemia, and hypertension between males and females, and to clarify the determinants of diabetes, hyperlipidemia, and hypertension in Taiwan. In this cross‐sectional study, 7,578 subjects were selected from the general population by stratified random sampling for the Surveillance of Taiwanese Civil Health in 2002. Blood samples were taken and information on body composition, demographics, exercise and dietary habits, and medical and drug histories were obtained from structured interviews administered by well‐trained interviewers. A total of 6,600 subjects (87.1%), aged 15.6–95.0 years old, completed the survey. The overall prevalences of diabetes, hyperlipidemia, and hypertension were 9.9%, 22.8%, and 15.7%, respectively, and hyperlipidemia (27.0%) and hypertension (19.2%) were more prevalent in males. Males were more likely to have high‐fat and high‐cholesterol diets, compared with females. Although there were differences in the prevalences of hyperlipidemia and hypertension between the sexes, adjusted logistic regression analysis demonstrated little contribution of diet and exercise habits to the risks of diabetes, hyperlipidemia, or hypertension after adjusting for age, sex, waist‐to‐hip ratio, serum blood sugar levels, cholesterol, triglycerides, apolipoprotein A1, apolipoprotein B, glutamate oxaloacetate transaminase, glutamate pyruvate transaminase, creatinine, uric acid, and blood pressure.