bluuebunny/crossref_metadata_2025 huggingface dataset:
Transport and magnetic properties of Fe3Si epitaxial films
Authors: Vinzelberg H. , Schumann J. , Elefant D. , Arushanov E. , Schmidt O. G.
Published: November 2008

The paper presents resistivity and magnetization measurements on nearly stoichiometric Fe3Si films epitaxially grown on GaAs substrates by electron-beam evaporation in an ultrahigh vacuum chamber. In the low-temperature resistivity a T3 term was found in all samples. A term like that is known to describe the anomalous single-magnon scattering processes in half-metallic materials and confirms so for our samples the hypothesis of half-metallic ferromagnetism in Fe3Si. The films show an anisotropic magnetoresistance in low magnetic fields. In high magnetic fields a negative longitudinal and transverse magnetoresistance (MR) has been observed linearly depending on the field strength. In the vicinity of 200 K the MR shows maximum absolute values up to 1.5% at magnetic fields of about 8 T. From the magnetization measurements a magnetic moment of 0.86μB/atom was obtained, which is close to that of bulk Fe3Si.
Growth evolution of surface nanowires and large anisotropy of conductivity on MgZnO/ZnO quantum wells based on M-nonpolar (10−10) ZnO
Authors: Matsui Hiroaki , Hasuike Noriyuku , Harima Hiroshi , Tabata Hitoshi
Published: November 2008

Self-organized surface nanowires were formed on M-nonpolar (10−10) ZnO homoepitaxial layer surfaces. High-resolution transmittance electron microscopy showed that the surface nanowires possessed a flat plateau at the top and a side facet with constant step spacing at the atomic scale. In and ex situ observations of layer growth revealed that anisotropic islands appeared after growing two-dimensional surfaces and that these gradually changed to nanowire structures with increasing layer thickness. Their growth origin, identified from theoretical parameter fittings based on a step-edge barrier model, was close to that of O-polar ZnO growth. A large difference in electron transport was clearly observed in Mg0.12Zn0.88O/ZnO quantum wells (QWs). Transport anisotropy correlated strongly with the surface morphology and with the structural quality of QWs, as confirmed by polarized photoluminescent spectroscopy. Finally, as a possible mechanism of anisotropic electron transport, we suggest that the electron motion perpendicular to the nanowire arrays was strongly restricted due to a potential barrier caused by an interface roughness of the surface nanowires.
Effective Hamiltonian for chaotic coupled oscillators
Authors: Chakraborty Aniruddha , Kellman Michael E.
Published: November 2008

A generalized effective fitting Hamiltonian is tested against a model system of highly excited coupled Morse oscillators. At energies approaching dissociation, a very few resonance couplings in addition to the standard 1:1 and 2:2 couplings of the Darling–Dennison Hamiltonian suffice to fit the spectrum and match the large-scale features of the mixed regular and chaotic phase spaces, consisting of resonance zones organized around periodic orbits of low order that break the total polyad action.
Flexible pentacene ion sensitive field effect transistor with a hydrogenated silicon nitride surface treated Parylene top gate insulator
Authors: Diallo K. , Lemiti M. , Tardy J. , Bessueille F. , Jaffrezic-Renault N.
Published: November 2008

We report on the realization of flexible ion sensitive organic field effect transistors based on pentacene on which Parylene-C was deposited as top gate dielectric. In order to create proton sensitive sites at the insulator/electrolyte interface, Parylene-C surface has been covered with a thin layer of hydrogenated silicon nitride (SiN:H) deposited by photochemical vapor deposition at moderate temperature. The combination of Parylene and SiN:H enables the realization of highly reproducible and good performance transistors as well as ion sensitive sensors with an excellent pH response both in the acidic and alkaline pH range in a nearly all plastic technology.
Hot electron effects and nonlinear transport in hole doped manganites
Authors: Jain Himanshu , Raychaudhuri A. K.
Published: November 2008

We show that strong nonlinear electron transport in the ferromagnetic insulating (FMI) state of manganites, responsible for phenomena such as colossal electroresistance and current induced resistance switching, can occur due to a hot electron effect. In the FMI state, which we show is an insulator with a Coulomb gap, the temperature of the electron and lattice baths can decouple at high input power levels, leading to heating of the electron bath. Parameters of the hot electron effect model were independently determined via time dependence experiments and are in good agreement with the experimental values.
Dynamics of photoalignment in azo-dye-doped liquid crystals
Authors: Huang Chia-Yi , Lin Yi-Ru , Lo Kuang-Yao , Lee Chia-Rong
Published: November 2008

A transmitted light without analyzer was led into the pump-probe twist nematic experiment in azo-dye-doped liquid crystals to observe the light scattering from the dye-adsorbed surface during photoalignment. The morphology of the dye-absorbed surface monitored by this transmitted light is correlated with the formation of the ripple structure, which is reflected by the anchoring of the dye-adsorbed layer, which is, in turn, revealed by measuring the surface director reorientation angle throughout the process. As the regular ripple structure is gradually formed, the Rayleigh scattering is transferred to the Mie scattering since the scale of the ripple structure is at the wavelength.
2-Alkyl-4-hydroxymethylfuran-3-carboxylic acids, antibiotic production inducers discovered by
Streptomyces coelicolor
genome mining
Authors: Corre Christophe , Song Lijiang , O'Rourke Sean , Chater Keith F. , Challis Gregory L.
Published: November 2008

All of the genetic elements necessary for the production of the antibiotic methylenomycin (Mm) and its regulation are contained within the 22-kb
mmy-mmf
gene cluster, which is located on the 356-kb linear plasmid SCP1 of
Streptomyces coelicolor
A3(
2
). A putative operon of 3 genes within this gene cluster,
mmfLHP
, was proposed to direct the biosynthesis of an A-factor-like signaling molecule, which could play a role in the regulation of Mm biosynthesis. The
mmfLHP
operon was expressed under the control of its native promoter in
S. coelicolor
M512, a host lacking the SCP1 plasmid, and the ability to produce prodiginine and actinorhodin antibiotics. Comparative metabolic profiling led to the identification and structure elucidation of a family of 5 new 2-alkyl-4-hydroxymethylfuran-3-carboxylic acids (AHFCAs), collectively termed Mm furans (MMFs), as the products of the
mmfLHP
genes. MMFs specifically induce the production of the Mm antibiotics in
S. coelicolor
. Comparative genomics analyses and searches of the natural product chemistry literature indicated that other streptomycetes may produce AHFCAs, suggesting that they could form a general class of antibiotic biosynthesis inducers in
Streptomyces
species, with analogous functions to the better known γ-butyrolactone regulatory molecules.
Uroporphyrinogen decarboxylation as a benchmark for the catalytic proficiency of enzymes
Authors: Lewis Charles A. , Wolfenden Richard
Published: November 2008

The magnitude of an enzyme's affinity for the altered substrate in the transition state exceeds its affinity for the substrate in the ground state by a factor matching the rate enhancement that the enzyme produces. Particularly remarkable are those enzymes that act as simple protein catalysts, without the assistance of metals or other cofactors. To determine the extent to which one such enzyme, human uroporphyrinogen decarboxylase, enhances the rate of substrate decarboxylation, we examined the rate of spontaneous decarboxylation of pyrrolyl-3-acetate. Extrapolation of first-order rate constants measured at elevated temperatures indicates that this reaction proceeds with a half-life of 2.3 × 10
9
years at 25 °C in the absence of enzyme. This enzyme shows no significant homology with orotidine 5′-monophosphate decarboxylase (ODCase), another cofactorless enzyme that catalyzes a very slow reaction. It is proposed that, in both cases, a protonated basic residue (Arg-37 in the case of human UroD; Lys-93 in the case of yeast ODCase) furnishes a counterion that helps the scissile carboxylate group of the substrate leave water and enter a relatively nonpolar environment, stabilizes the incipient carbanion generated by the departure of CO
2
, and supplies the proton that takes its place.
Current approaches and future directions for contaminant-related impact assessments in coastal environments: Brazilian perspective
Authors: Nipper M.
Published: November 2008

Coastal ecosystems are subject to the discharge of contaminants via sewage, industrial effluents, storm water runoff, dredged material and accidental chemical spills. The majority of contaminants reaching the ocean tend to be adsorbed to particulate matter and eventually settle on the ocean floor, where they can deleteriously affect the sediment-associated community. The degree to which a receiving body is impacted is usually assessed by the analysis of the sediments from the area of concern. If chemical data generated by monitoring programs are available, they can be compared to Sediment Quality Guidelines to help identify a potential problem. A more cost-effective approach involves the use of a sensitive toxicity test to identify areas of concern, with comprehensive chemical analyses conducted at a later stage and focusing on the toxic sites identified in the initial screening survey. More complex studies involve the assessment of the benthic communities, in addition to toxicity tests and chemical analyses can be conducted. While methodologies for chemical and benthic community assessments are relatively well established, several approaches can be used to determine sediment toxicity, including acute or chronic tests, conducted in the laboratory or in situ, on the whole sediment or the liquid phase. Several factors should be considered when interpreting toxicity test results, such as the enhancement of toxicity by the photo-oxidation of organic chemicals by ultraviolet light (UV), and confounding factors such as salinity, ammonia, sulfides, particle size distribution, organic matter content, and acid volatile sulfides (AVS). Once an impact has been identified, toxicity identification evaluation (TIE) procedures can be applied to help establish the chemical or classes of chemicals responsible for the observed adverse effects. The international and Brazilian scientific literatures are reviewed to illustrate these approaches.
Land use, habitat, and water quality effects on macroinvertebrate communities in three watersheds of a lake michigan associated marsh system
Authors: Stewart P.M. , Butcher J.T. , Swinford T.O.
Published: November 2008

Three watersheds within a marsh system draining into Lake Michigan in northwest Indiana, USA, were studied for differences among land use, habitat conditions and water quality to determine their influence on macroinvertebrate community structure. Much of this area had been altered for agricultural, commercial, industrial and residential land uses. Land use, habitat conditions and water quality were significantly different among watersheds. Water quality varied more among streams than within streams. Several variables were related to land use, especially dissolved ions. Macroinvertebrate communities depicted neither a healthy wetland nor a healthy stream system. Some sites were typical of a sand-based, erosional stream system and others were more typical of a wetland system. Communities were different both in and among streams; relationships with water chemistry variables and land use suggested that community structure was a function of local-scale, abiotic factors rather than watershed-scale characteristics. These results show the importance of local-scale influences on the structure and function of macroinvertebrate communities. The development of the methods used to measure these local-scale landscape factors is important to restoration and management.
Monitoring and assessment of the environment in the Lake Baikal region
Authors: Anokhin Yu.A. , Izrael Yu.A.
Published: November 2008

Analysis of many years’ observations of the environment in the Lake Baikal basin leads to the conclusion that the levels of pollutants in Baikal are extremely low, scarcely above the global background of biospheric pollution.

Economic activity in the Baikal watershed basin is a potential threat to the environment. The main influences are global environment and climate change, the Irkutsk dam on the Angara River and pollution of the environment. These impacts have been analyzed on a regional basis. Since the early 1970s routine information has come from monitoring programs for the Lake Baikal.

Models (dynamic and statistical) have been developed to describe and predict changes in the state of the environment (ambient air and precipitation, waters of the Lake Baikal and the tributaries, soils of the region and lake sediment, biota).
Hydrochemistry of southern Lake Baikal
Authors: Grosheva E.I. , Loseva R.P. , Sudakova N.D. , Kusner Y.S.
Published: November 2008

Recent chemical indices of water quality of southern Lake Baikal are given: colour, pH, BOD, COD and the principal ions. Chemical homogeneity and stability of the ionic composition of Lake Baikal water compared to observations in the last 30 years was confirmed.
Estimation of the influence of the Chernobyl accident on the Baikal drainage basin
Authors: Politov S.V. , Anokhin Yu.A.
Published: November 2008

For the first time, contamination levels of cesium due to the Chernobyl accident in water of highland lakes (and soils from their watersheds) of the Lake Baikal drainage basin, have been measured. The reason for this study was that the main long-range transportation of Chernobyl accident products in an easterly direction took place at high altitudes (above 2 km).

The amount of Chernobyl 137Cs, estimated on the basis of 134Cs content, varied in soils from 2 to 7% in the low-mountain areas, from 13 to 16% in the highlands and from 23 to 34% in the water of highland lakes. The estimated total deposition of cesium in the Baikal drainage basin was estimated to be 0.3% of the total Chernobyl emission.
Assessing pollution and UV-enhanced toxicity in Torsviken, Sweden, a shallow bay exposed to contaminated dredged harbor sediment and hazardous waste leachate
Authors: Wernersson A.-S. , Dave G. , Nilsson E.
Published: November 2008

Torsviken is a small bay close to the city of Gothenburg, Sweden. Part of the bay has been used for disposal of dredged harbor sediment since the 1970s. Other potential sources of contamination are a deposit site and treatment facility for hazardous waste. The area has been classified as ecologically sensitive and is of great ornithological interest. Birds are abundant and several rare species have been observed. In this study, pollution was assessed by analyzing concentrations of polycyclic aromatic hydrocarbons, polychlorinated biphenyls and heavy metals and by measuring toxicity of sediment samples to Daphnia magna, Nitocra spinipes, Chironomus riparius and Hyalella azteca. The combined exposure to several contaminants and solar light can enhance toxic effects, and since Torsviken is a shallow bay (maximum depth 2 m), organisms surviving the bioassays were exposed to simulated ultraviolet (UV) light of site-relevant intensity for 2 h to detect potential UV-enhanced toxicity. Torsviken is subdivided into three basins and the concentrations of most investigated contaminants, especially polycyclic aromatic hydrocarbons and polychlorinated biphenyls, were 2–5 times higher in the inner (western) area compared to the outer (eastern) areas. Acute sediment toxicity was found primarily in Nitocra, but there was no clear difference between the two areas of Torsviken. Ultraviolet-induced toxicity also occurred especially in Nitocra but only in the western area where organic pollutants are elevated in concentration. In the same sediment sampling site that caused the highest increase in mortality in Nitocra, there was also a significant response by Daphnia after UV treatment. Correlations between the toxicity enhancement (measured as % of surviving Nitocra from the bioassays that died after subsequent exposure to UV light) and chemical concentrations were found for several of the pollutants, including polycyclic aromatic hydrocarbons, polychlorinated biphenyls, mercury and lead, indicating that some of these substances were bioavailable and induced toxicity with UV irradiation. The results support the need to develop special sediment quality guidelines for shallow sites, where the phototoxic properties of pollutants should be accounted for.
Biological impact of lipophilic sediment extracts from the Kafue River, Zambia, in microinjected rainbow trout yolk-sac fry and chick embryo livers exposed in vitro
Authors: Norrgren L. , Brunström B. , Engwall M. , Mwase M.
Published: November 2008

Lipophilic sediment extract originating from the Kafue River, Zambia, was evaluated for toxic potency. Two different bioassays were used. In the first, sediment extracts were injected into newly hatched rainbow trout yolk-sac fry, and in the second chick embryo livers were incubated in vitro in different concentrations of the sediment extract. A dose-dependent ethoxyresofurin-O-deethylase (EROD) induction was recorded in both experiments. Furthermore, various types of intracellular alterations characterized by degenerative and necrotic changes were observed in the hepatocytes of the exposed groups. These findings indicate the presence of EROD inducing dioxin-like lipophilic substances in sediment extracts originating from the Kafue River near the town of Kitwe.
The ecosystem pyramid and the means for attaining ecological sustainability: an essay in honour of Jack Christie
Authors: Minns C.K.
Published: November 2008

This essay is presented in honour of Jack Christie and his life-long dedication to the promotion of an ecosystem approach to the management of human affairs in the biosphere. The essay has four sections. First, I review and reflect on the personal and professional interactions I had with Jack Christie for more than 25 years. Those interactions often centred on questions of ecosystem management in the Great Lakes and beyond, but especially in the Bay of Quinte area where Jack lived and worked. Second, I consider the role of metaphorical symbols in shaping our interactions with and behaviour towards ecosystems. I offer arguments for adopting a metaphor—an ecosystem is a stepped pyramid—as a basis for shifting our thinking mode regarding ecosystems. Third, I turn to an examination of some of the means by which human society might return to ecological sustainability. I describe and compare ecological, social, and economic mechanisms. Fourth, given the current situation and the options, I conclude with a personal view of our future prospects.
Sediment toxicity and contaminants in the Kattegat and Skagerrak
Authors: Dave Göran , Nilsson Eva
Published: November 2008

Sediment bioassays have usually been applied to sediments from sites close to known sources of pollution such as harbours or major industrial sites. In this study sediment bioassays were conducted on samples from 120 sites in the Kattegat and Skagerrak (North Sea) at water depths ranging from 4 to 682 m. Sediment toxicity to Daphnia magna, expressed as immobility after 48 h exposure to 16% sediment (wet weight) ranged from 0 to 95%. Sediment toxicty to Nitocra spinipes, expressed as the 96 h LC50 for sediment in water, ranged from 0.61 to 88% dry weight. The responses obtained in duplicate bioassay test vessels showed good correlation (r = 0.7–0.8), but toxicity to Daphnia was not correlated with toxicity to Nitocra. High sediment toxicity was not restricted to areas close to industrial sites and harbours, but was found also in open sea areas. Analysed sediment concentrations of contaminants (heavy metals, organochlorines and polyaromatic hydrocarbons) at 25 of these 120 sites were tested for correlation with sediment toxicity, but no correlations, or rather weak ones, were found. Further, the concentrations of single contaminants were usually below those, which are considered harmful to aquatic organisms (tentative sediment quality criteria). Therefore, none of the single analysed contaminants seems to cause the observed sediment toxicity. No improvement in correlation was achieved when using an additive model of joint toxicity between different groups of contaminants and the combined toxicity to Daphnia and Nitocra. Therefore, the cause of the sediment toxicity is so far unknown, and no hazard assessment based on the analysed contaminants was warranted. The average immobility of Daphnia after exposure to 16% sediment (wet weight) for 48 h was 29%, and the average 96 h LC50 for Nitocra exposed to various concentrations of sediment was 11.4% (dry weight) of sediment in dilution water. A tentative hazard assessment based on these average results from both bioassays suggested that sediment toxicity in the Kattegat and Skagerrak must be reduced by on average four times to approach a Predicted Effect Level (PEL) allowing 50% survival.
Summer Peaks in the Incidences of Gram-Negative Bacterial Infection Among Hospitalized Patients
Authors: Perencevich Eli N. , McGregor Jessina C. , Shardell Michelle , Furuno Jon P. , Harris Anthony D. , Morris J. Glenn , Fisman David N. , Johnson Judith A.
Published: November 2008

Objective.

Recognition of seasonal trends in hospital infections may improve diagnosis, use of empirical therapy, and infection prevention interventions. There are very few data available regarding the seasonal variability of these infections. We quantified the seasonal variation in the incidences of hospital infection caused by common bacterial pathogens and estimated the association between temperature changes and infection rates.

Methods.

A cohort of all adult patients admitted to the University of Maryland Medical Center during the period from 1998 through 2005 was analyzed. Time-series analyses were used to estimate the association of the number of infections per month caused by Pseudomonas aeruginosa, Acinetobacter baumannii, Enterobacter cloacae, Escherichia coli, Staphylococcus aureus, and enterococci with season and temperature, while controlling for long-term trends.

Results.

There were 218,594 admissions to the index hospital, and analysis of 26,624 unique clinical cultures that grew the organisms of interest identified increases in the mean monthly rates of infection caused by P. aeruginosa (28% of isolates recovered; P < .01), E. cloacae (46%; P < .01), E. coli (12%; P < .01), and A. baumannii (21%; P = .06). For each 10°F increase, we observed a 17% increase in the monthly rates of infection caused by P. aeruginosa (P = .01) and A. baumanii (P = .05).

Conclusion.

Significantly higher rates of gram-negative infection were observed during the summer months, compared with other seasons. For some pathogens, higher temperatures were associated with higher infection rates, independent of seasonality. These findings have important implications for infection prevention, such as enhanced surveillance during the warmer months, and for choice of empirical antimicrobial therapy among hospitalized adults. Future, quasi-experimental investigations of gram-negative infection prevention initiatives should control for seasonal variation.
Otolith shape analysis: its application for discriminating between stocks of Irish Sea and Celtic Sea herring (Clupea harengus) in the Irish Sea
Authors: Burke Nóirín , Brophy Deirdre , King Pauline A.
Published: November 2008

Burke, N., Brophy, D., and King, P. A. 2008. Otolith shape analysis: its application for discriminating between stocks of Irish Sea and Celtic Sea herring (Clupea harengus) in the Irish Sea. – ICES Journal of Marine Science, 65: 1670–1675. The extensive movement of Celtic Sea juvenile Atlantic herring (Clupea harengus) during the first year of life into the Irish Sea results in two stocks of herring living together on Irish Sea nursery grounds: the resident autumn-spawned juveniles that originate in the Irish Sea, and the winter-spawned juveniles that hatch in the Celtic Sea and drift into the Irish Sea as larvae. Measurements of otolith increment width can be used to distinguish between the fast-growing winter-spawned and the slow-growing autumn-spawned stocks, but this method can be time-consuming. Otolith shape analysis is investigated as an alternative method for discriminating between seasonal spawning stocks. Juvenile herring collected from nursery grounds in the Irish Sea in 2006 were classified as autumn- or winter-spawned using increment width measurements. Otolith shape was defined using shape indices and Fourier descriptors. Juveniles were classified successfully to hatch type with a high degree of accuracy (86–87%) using shape variables. The potential use of otolith shape analysis for identifying Celtic Sea juvenile herring in the Irish Sea and its possible use for other mixed-herring stock assessments are discussed.
Original disorder–order transition related to electronic and magnetic properties in the thermoelectric misfit phase [Ca2CoO3][CoO2]1.62
Authors: Muguerra Hervé , Grebille Dominique
Published: November 2008

A structural phase transition is shown around 400 K for the thermoelectric lamellar misfit cobalt oxide [Ca2CoO3][CoO2]1.62. This transition is related to a rearrangement of the central [CoO] layer of the [Ca2CoO3] slab of this structure, characterized by a commensurate intrinsic modulation q
2 = 2\over 3a
* − 1\over 3c
*. The partial residual disorder related to split Co and O atomic sites along the misfit b direction disappears and one can describe this layer with its triple chains as a modulated configuration with a regular and not distorted periodicity along b. This phase transition is associated with small changes observed in the transport and magnetic properties as a function of temperature.
Improvement of anisotropic displacement parameters from invariom-model refinements for three L-hydroxylysine structures
Authors: Dittrich B. , McKinnon J. J. , Warren J. E.
Published: November 2008

Three L-hydroxylysine structures have been determined at 100 K by single-crystal X-ray diffraction. High-resolution data using either a laboratory or synchrotron source were collected and subjected to invariom- and independent atom-model (IAM) refinements. Anisotropic displacement parameters (ADPs) obtained from invariom refinement were compared (i) with results from a full multipole and (ii) with an IAM high-order refinement. Differences were visualized with the program PEANUT and were complemented by quantitative results from a Hirshfeld test. Influences of scale factor differences, and of refinement against F^2 versus F, have been investigated. Systematic errors were observed in the IAM, especially when only low-order data were available. Although these errors were reduced in high-order IAM refinements, they only disappeared in charge density – and likewise – invariom refinements.
Regulatory T cells fail to suppress CD4+ T‐bet+ T cells in relapsing multiple sclerosis patients
Authors: Frisullo Giovanni , Nociti Viviana , Iorio Raffaele , Patanella Agata K. , Caggiula Marcella , Marti Alessandro , Sancricca Cristina , Angelucci Francesco , Mirabella Massimiliano , Tonali Pietro A. , Batocchi Anna P.
Published: November 2008

Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system and a defect in the regulatory T‐cell subset seems to be involved in the pathogenesis of the disease. Foxp3 is a transcription factor that is selectively expressed in CD4+ CD25+ regulatory T cells and is required for their development and function. T‐bet is a key transcription factor for the development of T helper 1 (Th1) cells. We found that both the percentage of circulating CD4+ CD25+ Foxp3+ cells and Foxp3 expression were lower in relapsing‐remitting (RR) MS patients during relapses than during remission. Otherwise, the percentage of CD4+ T‐bet+ T cells and T‐bet expression in CD4+ T cells were higher in relapsing than in remitting RRMS patients. CD4+ CD25+ T cells both from relapsing and from remitting RRMS patients showed significantly less capacity than corresponding cells from healthy subjects to suppress autologous CD4+ CD25− T‐cell proliferation, despite a similar Foxp3 expression level. CD4+ CD25+ T cells from healthy subjects and patients in remission clearly reduced T‐bet mean fluorescence intensity (MFI) in CD4+ CD25− T cells up to a ratio of 1:10, whereas CD4+ CD25+ T cells from patients in relapse were able to reduce T‐bet expression only at a high ratio. Our data indicate that the increased number of regulatory T (T‐reg) cells and the increased Foxp3 expression in circulating CD4+ CD25+ T cells may contribute to the maintenance of tolerance in the remission phase of MS. Moreover, the inhibitory capacity of CD4+ CD25+ T cells seems to be impaired in relapsing patients under inflammatory conditions, as shown by the high levels of T‐bet expression in CD4+ T cells.
Induction of copper/zinc‐superoxide dismutase by CCL5/CCR5 activation causes tumour necrosis factor‐α and reactive oxygen species production in macrophages
Authors: Qiu Lei , Ding Li , Huang Jin , Wang Dong , Zhang Junping , Guo Baoyu
Published: November 2008

Using two‐dimensional sodium dodecyl sulphate–polyacrylamide gel electrophoresis, we found that copper/zinc superoxide dismutase (Cu/Zn‐SOD, SOD‐1) was induced in constructed CCR5 stably transfected HEK 293 cells, but not in mock cells, treated with CCL5. CCL5‐induced SOD‐1 expression was also confirmed in HEK 293‐CCR5 cells and CCR5‐positive granulocyte–macrophage colony‐stimulating factor‐induced human macrophages and murine macrophage RAW264.7 cells. CCL5 and CCR5 interaction induced SOD‐1 expression mainly via MEK–ERK activation. In addition, we provided evidence that upregulation of SOD‐1 by CCL5/CCR5 activation occurred in parallel with the increased release of tumour necrosis factor‐α and nitric oxide and production of intracellular reactive oxygen species as well as enhanced nuclear factor‐κB transcriptional activity in CCR5‐positive RAW264.7 cells. Conversely, the MEK1/2 inhibitor PD98059 significantly inhibited SOD‐1 expression with the decrease of these biological responses. More importantly, inhibition of SOD‐1 activity by disulfiram also strongly inhibited the CCL5‐induced biological effects. These data suggest that SOD‐1 mediates CCR5 activation by CCL5 and that pharmacological modulation of SOD‐1 may be beneficial to CCR5‐associated diseases.
Acetylcholinesterase genes in the basal Hexapod Orchesella villosa
Authors: Nardi F. , Barazzuoli B. , Ciolfi S. , Carapelli A. , Dallai R. , Frati F.
Published: November 2008

Acetylcholinesterase (AChE) is a key enzyme of the cholinergic nerve system. Of the two forms found in insects, the predominant one is active in the synapses and is the target of organophosphate and carbamate insecticides, while the role of the second is currently unknown. Two acetylcholinesterase cDNAs from the basal hexapod Orchesella villosa have been characterized and compared with others reported form insects. One form conforms well to the typical structure, while the other is characterized by an unusual 3′ region. No amino acid mutation could be directly associated with known resistance mutations in other insect species or to a clear signal of selection in the distribution of alleles, although the action of some population process is suggested.
Estimation of infectious dose and viral shedding rates for infectious pancreatic necrosis virus in Atlantic salmon, Salmo salar L., post‐smolts
Authors: Urquhart K , Murray A G , Gregory A , O’Dea M , Munro L A , Smail D A , Shanks A M , Raynard R S
Published: November 2008

Infectious dose and shedding rates are important parameters to estimate in order to understand the transmission of infectious pancreatic necrosis virus (IPNV). Bath challenge of Atlantic salmon post‐smolts was selected as the route of experimental infection as this mimics a major natural route of exposure to IPNV infection. Doses ranging from 102 to 10−4 50% end‐point tissue culture infectious dose (TCID50) mL−1 sea water were used to estimate the minimum infectious dose for a Scottish isolate of IPNV. The minimum dose required to induce infection in Atlantic salmon post‐smolts was <10−1 TCID50 mL−1 by bath immersion (4 h at 10 °C). The peak shedding rate for IPNV following intraperitoneal challenge using post‐smolts was estimated to be 6.8 × 103 TCID50 h−1 kg−1 and occurred 11 days post‐challenge. This information may be incorporated into mathematical models to increase the understanding of the dispersal of IPNV from marine salmon sites.
OLD ENGLISH STRESS, HIGH VOWEL DELETION AND GEMINATION: TWO PROSODIC PLANE THEORY
Authors: Kaminashi Keiko
Published: November 2008

An attempt will be made to analyze OE stress, High Vowel Deletion (HVD) and Gemination in the framework of ‘Two Prosodic Plane Theory’ in which the syllable plane and the grid plane are separately represented. On the grid plane, grid constituent structures which represent stress contours are constructed by means of the mechanisms to be proposed. It will become clear that grid transformations (X(=grid)‐delinkings) are involved with both HVD and Gemination. The principles of grid transformation, i. e. the Head Grid Principle and the Minimal Foot Principle (in particular) will play an important role in explaining these phonological processes.
REFERENT GRAMMAR MACHINE TRANSLATION WITH DISCOURSE ANAPHORIC EXTENSION
Authors: Yaeger George , Kosaka Michiko
Published: November 2008

While unification grammars have been in existence for some time and have given birth to grammar formalisms such as Generalized Phrase Structure Grammar (GPSG), it is only recently that computational tools such as Prolog Definite Clause Grammars (DCG) have allowed direct implementation of such grammars on personal computers. A very promising new formalism Referent Grammar is an outgrowth of these events. Referent Grammar (RG) is a sub‐class of GPSG which can be directly implemented in Prolog DCG and provides weak generative power at least equal to GPSG. This paper describes the Referent Grammar formalism and the research MT system developed using RG and anaphoric pronoun resolution extensions to RG. It also describes plans for combining sublanguage analysis with RG.
ON THE BASQUE‐CAUCASIAN HYPOTHESIS
Authors: Sturua Natela
Published: November 2008

Two stages are considered in the evolution of the Basque‐Caucasian hypothesis: (a) “pre‐scientific”, based on a coincidence of the names of the two Iberias‐that of the Iberian Peninsula and of the Caucasus‐in ancient Greek and Roman sources; (b) “scientific”, involving the search for genetic and typological links of the Basque culture and language. In this connection, the importance of the decipherment of Iberian inscriptions of the Peninsula is noted. Comparative‐historical and typological approaches in Basque‐Caucasian studies are reviewed and illustrated by the results of the author's research.
A NEW ANALYSIS FOR MACHINE TRANSLATION OF THE AUXILIARY AND MAIN VERB COMPLEX
Authors: Sigurd Bengt
Published: November 2008

Abstract. The analysis of the verb phrase poses interesting problems. This paper suggests a binary solution where the auxiliary is treated as one constituent and the main verb complex as another. Auxiliaries are thus not treated as main verbs as was suggested by Ross 1967 (and followed in the first version of Referent Grammar, Sigurd 1987). The auxiliary may be lacking (latent, empty), in which case the main verb carries the tense (finite) marker, or the auxiliary may be present, in which case the auxiliary carries the tense marker, while the main verb complex must be nonfinite. In the main verb complex, the main verb may be preceded by almost any number of nonfinite auxiliaries, and it is this possibility which creates theoretically interesting chains of nonfinite verb forms such as Swedish Eva måste ha velat kunna våga (att) hoppa (Eva must have wanted to be able to dare (to) jump). A basic idea of this paper is that the nonfinite auxiliary verb forms can be added as prefixes (or as in G man suffixes) by a kind of morphological rule.
A REFERENT GRAMMAR TREATMENT OF SOME PROBLEMS IN THE BULGARIAN NOMINAL PHRASE
Authors: Pericliev Vladimir
Published: November 2008

Abstract. The paper addresses some problems of the Bulgarian nominal phrase within the framework of Referent Grammar, a grammatical model used for computer analysis, generation and translation in the SWETRA project (Swedish Computer Translation Center at the Department of Linguistics and Phonetics, Lund University). In particular, the computer implementation of agreement, the choice of articled forms, and the movement of clitic words in the Bulgarian nominal phrase are discussed.
THE FEATURE [ASP] IN ICELANDIC PHONOLOGY*
Authors: Jónsson Jóhannes G.
Published: November 2008

Abstract. This paper argues that the surface distribution of aspirated stops in Icelandic is governed by licensing conditions on the feature [asp(irated)] (cf. Lombardi 1991). On this view, the dialectal difference in the treatment of aspirated stops in Icelandic reflects different licensing conditions on [asp]. Moreover, it is argued that sonorant devoicing and preaspiration are one and the same process, i. e. relinking of unlicensed [asp] to an immediately preceding segment. Hence, the absence of sonorant devoicing in the North Dialect follows from the fact that [asp] is licensed on aspirated stops preceded by sonorants.
CASE PROPERTIES OF CLAUSES AND THE GREED PRINCIPLE*
Authors: Božković Željko
Published: November 2008

Abstract. In this paper I give an account of the descriptive generalization that although clauses can appear in Caseless positions, they need Case when they move to subject position or undergo Topicalization. The analysis presented in the paper is shown to have broad theoretical consequences. Among other things, it provides support for the Greed Principle. It also provides evidence that clauses can bear Case features and that direct object nominal elements undergoing syntactic movement from within VP must pass through Spec., AgroP in the overt syntax. I also argue that the facts considered in the paper provide evidence for the morphological and against the theta‐theoretic account of the Case Filter.
Catalyzing separation of carbon dioxide in thiamin diphosphate‐promoted decarboxylation
Authors: Kluger Ronald , Rathgeber Steven
Published: November 2008

Thiamin diphosphate‐dependent decarboxylases form addition intermediates between thiamin diphosphate (ThDP) and 2‐ketoacids. Although it appears that the intermediate should react without the intervention of catalysts, evidence has clearly shown that Brønsted acid catalysis occurs through a pre‐associated system. This can promote separation of carbon dioxide from the residual carbanion by protonation of the carbanion. Proteins operate through pre‐association and may readily promote the separation of carbon dioxide by protonating or oxidizing the nascent carbanion. Alternatively, a nucleophilic side chain may trap carbon dioxide as an unstable hemi‐carbonate. Mutagenesis experiments by others have shown that enhanced activity due to the protein in the presence of thiamin diphosphate does not depend on the presence of any one proton donor, consistent with pooled activity within the active site. This form of catalysis has not been widely recognized, but should be considered an integral aspect of enzyme‐promoted decarboxylation.
Roles of adenine anchoring and ion pairing at the coenzyme B12‐binding site in diol dehydratase catalysis
Authors: Ogura Ken‐ichi , Kunita Shin‐ichi , Mori Koichi , Tobimatsu Takamasa , Toraya Tetsuo
Published: November 2008

The X‐ray structure of the diol dehydratase–adeninylpentylcobalamin complex revealed that the adenine moiety of adenosylcobalamin is anchored in the adenine‐binding pocket of the enzyme by hydrogen bonding of N3 with the side chain OH group of Serα224, and of 6‐NH2, N1 and N7 with main chain amide groups of other residues. A salt bridge is formed between the ε‐NH2 group of Lysβ135 and the phosphate group of cobalamin. To assess the importance of adenine anchoring and ion pairing, Serα224 and Lysβ135 mutants of diol dehydratase were prepared, and their catalytic properties investigated. The Sα224A, Sα224N and Kβ135E mutants were 19–2% as active as the wild‐type enzyme, whereas the Kβ135A, Kβ135Q and Kβ135R mutants retained 58–76% of the wild‐type activity. The presence of a positive charge at the β135 residue increased the affinity for cobalamins but was not essential for catalysis, and the introduction of a negative charge there prevented the enzyme–cobalamin interaction. The Sα224A and Sα224N mutants showed a kcat/kinact value that was less than 2% that of the wild‐type, whereas for Lysβ135 mutants this value was in the range 25–75%, except for the Kβ135E mutant (7%). Unlike the wild‐type holoenzyme, the Sα224N and Sα224A holoenzymes showed very low susceptibility to oxygen in the absence of substrate. These findings suggest that Serα224 is important for cobalt–carbon bond activation and for preventing the enzyme from being inactivated. Upon inactivation of the Sα224A holoenzyme during catalysis, cob(II)alamin accumulated, and a trace of doublet signal due to an organic radical disappeared in EPR. 5′‐Deoxyadenosine was formed from the adenosyl group, and the apoenzyme itself was not damaged. This inactivation was thus considered to be a mechanism‐based one.
DYRK1A phosphorylates caspase 9 at an inhibitory site and is potently inhibited in human cells by harmine
Authors: Seifert Anne , Allan Lindsey A. , Clarke Paul R.
Published: November 2008

DYRK1A is a member of the dual‐specificity tyrosine‐phosphorylation‐regulated protein kinase family and is implicated in Down’s syndrome. Here, we identify the cysteine aspartyl protease caspase 9, a critical component of the intrinsic apoptotic pathway, as a substrate of DYRK1A. Depletion of DYRK1A from human cells by short interfering RNA inhibits the basal phosphorylation of caspase 9 at an inhibitory site, Thr125. DYRK1A‐dependent phosphorylation of Thr125 is also blocked by harmine, confirming the use of this β‐carboline alkaloid as a potent inhibitor of DYRK1A in cells. We show that harmine not only inhibits the protein–serine/threonine kinase activity of mature DYRK1A, but also its autophosphorylation on tyrosine during translation, indicating that harmine prevents formation of the active enzyme. When co‐expressed in cells, DYRK1A interacts with caspase 9, strongly induces Thr125 phosphorylation and inhibits caspase 9 auto‐processing. Phosphorylation of caspase 9 by DYRK1A involves co‐localization to the nucleus. These results indicate that DYRK1A sets a threshold for the activation of caspase 9 through basal inhibitory phosphorylation of this protease. Regulation of apoptosis through inhibitory phosphorylation of caspase 9 may play a role in the function of DYRK1A during development and in pathogenesis.
Scopinella gallicola, a new species from rust galls of Endocronartium harknessii on Pinus contorta
Authors: Tsuneda A. , Hiratsuka Y.
Published: November 2008

A new species of Scopinella is described and illustrated. This species, Scopinella gallicola, occurs on Pinus contorta galls caused by Endocronartium harknessii. It differs from previously described species mainly in its unusual habitat, size, and shape of the ascocarp, and two- and four-spored asci. The Harziella anamorph is also described. No anamorph has been reported in other species.
Isolation of a dwarf plant responsive to exogenous GA3 from anther cultures of birdsfoot trefoil
Authors: Tomes Dwight T. , Peterson R. L.
Published: November 2008

A dwarf plant isolated from anther culture of a normal genotype of birdsfoot trefoil (Lotus corniculatus L. cv. Leo) has been isolated, characterized, and maintained as an in vitro shoot-tip culture. The dwarf condition is the result of a much shorter internode length when compared with a normal genotype in shoot tip culture. Dwarf shoots which are typically rosette respond to increased GA3 levels by increased internode growth. Normal genotypes are inhibited and eventually die as a result of increased levels of GA3 in the culture medium. This dwarf has the normal tetraploid chromosome number of 24, and although stable in shoot tip cultures since 1977, has not survived outside of in vitro shoot tip cultures.
Modeling no-take marine reserves in regulated fisheries: assessing the role of larval dispersal
Authors: McGilliard Carey R. , Hilborn Ray
Published: November 2008

We explored the effects of larval dispersal distance on the impact of no-take marine reserves (NTMRs) implemented in fisheries with catch regulations. NTMRs exist in many fisheries with harvest regulated by annual catch limits. In these fisheries, catch is taken from outside NTMRs, potentially resulting in reduced abundance outside NTMRs and an overall reduction in catch. We used a spatial model with two life stages (larvae and adults) to evaluate the effects of larval dispersal distance for fisheries managed by a total allowable catch (TAC) and an NTMR. We examined effects of the timing of density-dependent mortality in relation to larval movement. Abundance reached similar values for populations with long and short larval dispersal distances. Catch declined substantially for stocks with short larval dispersal distances. When larval dispersal distances were long, catch declined to values below maximum sustainable yield (MSY), but stabilized. Catch per unit effort (CPUE) declined to 9% of CPUE at MSY for stocks with short distance larval dispersal after the implementation of an NTMR; with long distance larval dispersal, CPUE declined to approximately 50% or less of the CPUE at MSY. The CPUE did not reflect trends in abundance after the implementation of an NTMR.
Deicing salt scaling resistance of concrete incorporating supplementary cementing materials: laboratory and field test data
Authors: Bouzoubaâ N. , Bilodeau A. , Fournier B. , Hooton R. D. , Gagné R. , Jolin M.
Published: November 2008

In this study, sidewalk sections were made in the field using seven concrete mixtures, applying a finishing and curing practice that is commonly used in Montréal, Canada. For each of the sidewalk sections, large slabs (1.2 m × 1.2 m) were cast from which specimens were cored and tested in the laboratory for determining their basic mechanical properties and deicing salt scaling resistance following ASTM C672 test procedures. Also, during the casting of the sidewalk, companion specimens were cast on site, using concrete from the same batch, and were subjected to the same tests as the “cored” specimens. The resistance to deicing salt scaling of these “laboratory specimens” was evaluated according to ASTM C672 and to BNQ NQ 2621–900 (2002 standard of the province of Quebec, Canada) test procedures. The results were compared with the performance of the sidewalk sections after four winters of outdoor exposure. The visual evaluation of the sidewalks after four winters has confirmed the severity of the ASTM C672 procedure and the adequateness of the BNQ procedure to better evaluate the deicing salt scaling resistance of concrete made with supplementary cementing materials (SCMs). The field evaluation should, however, continue for a longer period of time to increase the confidence in the BNQ test or to allow for changes as needed.