bluuebunny/crossref_metadata_2025 huggingface dataset:
Psychanalyse et didactique : à propos des représentations et de la causalité
Authors: Kerlan Alain
Published: June 2010

La psychanalyse interpelle le didacticien par sa méthode d'investigation des représentations psychiques. Les représentations des élèves sont en effet au centre des préoccupations de la didactique des sciences expérimentales. Toutefois, la méthode psychanalytique procède d'une conception générale de l'activité mentale et du fonctionnement de l'appareil psychique. Ce que la psychanalyse peut proposer, c'est peut-être moins un modèle méthodologique qu'un cadre conceptuel et théorique. La problématique relative aux représentations des élèves permet de l'éprouver.

Quelque conclusion qu'on en tire, l'approche psychanalytique interdit du moins d'ignorer que la pensée scientifique naît, s'éduque et s'instaure au sein d'une activité psychique globale à laquelle elle ne cesse pas d’appartenir.
Molecular detection of harmful algal blooms (HABs) using locked nucleic acids and bead array technology
Authors: Diaz Mara R. , Jacobson James W. , Goodwin Kelly D. , Dunbar Sherry A. , Fell Jack W.
Published: June 2010

Harmful algal blooms (HABs) are a serious public health risk in coastal waters. As the intensity and frequency of HABs continue to rise, new methods of detection are needed for reliable identification. Herein, we developed a high‐throughput, multiplex, bead array technique for the detection of the dinoflagellates Karenia brevis and Karenia mikimotoi. The method combined the Luminex detection system with two novel technologies: locked nucleic acid—modified oligonucleotides (LNA) and Mirus Label IT® nucleic acid technology. To study the feasibility of the method, we evaluated the performance of modified and unmodified LNA probes with amplicon targets that were biotin labeled with two different strategies: direct chemical labeling (Mirus Label IT) versus enzymatic end‐labeling (single biotinylated primer). The results illustrated that LNA probes hybridized to complementary single‐stranded DNA with better affinity and displayed higher fluorescence intensities than unmodified oligonucleotide DNA probes. The latter effect was more pronounced when the assay was carried out at temperatures above 53°C degree. As opposed to the enzymatic 5′ terminal labeling technique, the chemicallabeling method enhanced the level of fluorescence by as much as ~83%. The detection limits of the assay, which were established with LNA probes and Mirus Label IT system, ranged from 0.05 to 46 copies of rRNA. This high‐throughput method, which represents the first molecular detection strategy to integrate Luminex technology with LNA probes and Mirus Label IT, can be adapted for the detection of other HABs and is well suited for the monitoring of red tides at pre‐blooming and blooming conditions.
Multiple approaches to estimating air‐water gas exchange in small lakes
Authors: Cole Jonathan J , Bade Darren L. , Bastviken David , Pace Michael L. , Van de Bogert Matthew
Published: June 2010

The rate of gas exchange between air and water is an essential quantity in a number of contexts, from mass balances to the calculation of whole‐system metabolism. The exchange of a gas between water and the atmosphere is controlled by differential partial pressures of gases in air and in water (both straightforward to measure) and by the amount of turbulent energy exchange between the air‐water interface, the measurement of which is neither simple nor direct. This physical exchange is often expressed as a piston velocity (k). We compared four methods for estimating k in a series of small (0.3 to 45 ha), low‐wind (mean wind < 3 m s−1) lakes: 1) floating chambers using ambient CH4; 2) whole‐lake SF6 additions; 3) three wind‐based models from the literature; and 4) C mass balances constrained by whole‐lake 13C additions. All of the methods, with the exception of one wind‐based model, converged on values for k600 of between 0.35 and 0.74 m d−1 with no biases among methods. The floating chambers, if designed properly, are a cost‐effective way of obtaining site‐specific values of k for low wind lakes over fairly short time frames (hours).
Species richness estimation: Estimator performance and the influence of rare species
Authors: Reichert Katharina , Ugland Karl Inne , Bartsch Inka , Hortal Joaquín , Bremner Julie , Kraberg Alexandra
Published: June 2010

Species richness estimators (SREs) frequently exhibit widely different results when applied to the same data set. The lack of information on the true species number in an area hampers assessment of the performance of competing SREs. Marine invertebrates have been studied for more than 150 years on Helgoland (North Sea), and a fairly complete species list exists for this assemblage, providing a good opportunity for such comparisons. We evaluated the performance of 12 SREs using data on intertidal marine invertebrates of Helgoland. The Ugland TS estimator provided the most accurate estimate of total richness, whereas MMF, Semilog, and Weibull produced a moderate underestimation. The other SREs seriously under‐ or overestimated total richness. Although the Ugland TS estimator accounts for changes of species abundance distributions encountered when area increases, most SREs assume a homogeneous distribution. Analysis of separate accumulation curves for rare, intermediate, and common species revealed that the curvature of the randomized empirical accumulation curve of all the species is determined primarily by the occurrence of rare species. Thus, the influence of rare species was assessed through simulations of the Ugland TS. Linear extrapolation will under‐ or overestimate total richness if the occupancy of rare species is unusually low or high, respectively. The true occupancy of rare species in the Helgoland intertidal is likely to be close to the optimal interval revealed by our simulations, which provide a general framework for assessing the suitability of SREs for a given data set and thus improve the selection process of the optimal method.
Sensitivity of Some Freshwater Fish Species Used in Brazil
Authors: Bertoletti Eduardo
Published: June 2010

In order to compare the sensitivity of six freshwater fish species ecotoxicological assays were performed, under identical conditions, with the following chemicals: hexavalent chromium, copper, zinc, mercury, unionized ammonia, and pesticides formulations of H.C.H. and D.D.T. The differences in sensitivity were considered expressive when the ratio between 96 h-LC50s was > 2. The normalized 96 h-LC50s allowed to order the sensitivity of fish species, indicating that native species [Hemigrammus marginatus (bandeirinha) and Serrapinnus notomelas (piabinha)] are as sensitivity as traditional species [(Danio rerio (zebrafish) and Poecilia reticulata (guppy)]. Other exotic species, such as Cyprinus carpio (common carp) and Tilapia rendalli (tilápia), showed less sensitivity than other species studied. This study indicates that species such as Danio rerio and Poecilia reticulata can be used as substitute of native species in acute ecotoxicity assays with chemicals and liquid effluents.
Anthropic Impact Evaluation of Two Brazilian Estuaries Through Biomarkers in Fish
Authors: Domingos Fabíola X. Valdez , Assis H. C. S. , Silva M. D. , Damian R. C. , Almeida A. I. M. , Cestari M. M. , Randi M. A. F. , Ribeiro C. A. Oliveira
Published: June 2010

Coastal and estuarine areas can be impacted by several sources of anthropogenic activities derived from industries, agriculture, sewage and harbor activities. Two Brazilian estuarine areas (Piraquê – ES and Paranaguá – PR) located close to harbours, industries and sewage from urban centers were evaluated through analysis of somatic indexes, histopathological, biochemical and genetic biomarkers on fish. Histopathological lesions as lamellar fusion, hyperplasia, epithelial lifting, and second lamellae disorganization were found in gills. Necrosis was the main alteration observed in the liver of sampled animals and the occurrence of melano-macrophages in Cathorops spixii was similar among the evaluated areas. Cholinesterase activity increased in most of the contaminated areas. Genotoxic responses as micronucleus induction and occurrence of DNA strand breaks were detected in Piraquê and Paranaguá estuaries in all sampling seasons. Our results suggest that these areas are impacted by anthropogenic activities and that a multi-biomarker approach is valuable and recommended for environmental pollution evaluation.
Relationship Between Water Quality and Land use Along a Stretch of the Sorocaba River (SP)
Authors: Silva Alexandre Marco da , Rosa A. H. , Antunes F. M. , Nogueira D. P. , Lessa S. da S.
Published: June 2010

Considering that the land use activities have direct impacts on water resources, the aim of this paper is presenting the spatial variation of the following parameters: pH, apparent color, true color, turbidity, conductivity and chemical oxygen demand along a stretch of the Sorocaba River, located in Sorocaba Municipality. Field incursions were done in order to survey in-situ the conductivity and pH. Water samples were collected and transported to the laboratory for analysis of the remnant parameters. Conductivity and chemical demand of oxygen were the parameters that more closely revealed the degradationof the water quality. It was verified that the urban region was the main responsible by degradation of water quality and that vegetation patches did not improve the water quality patterns, just estilizaded them. Thus, although the Sorocaba River has been trying to control its levels of contamination, an extended work must be done in order to get better the water quality and its surroundings.
Environmental Risk Assessment of Lead Arsenate Based on Bioassays With Eight Non-target Organisms
Authors: Iannacone José , Alvariño L. , Paredes C.
Published: June 2010

Lead arsenate is one of the most employed pesticides in Peruvian agriculture. Protocols of bioassays allow us to determinate the effect of this pesticide on different biological components. The acute toxicity parameter more commonly employed is the median lethal concentration (LC50). This research aimed to evaluate the ecotoxicological effects of lead arseniate on eight non-target invertebrates. The folowing sequence in decresing acute ecotoxicity order in terms of arsenic after 48 h of exposure was found: Daphnia magna (EC50 = 3.1 mg L–1) > Trichogramma fuentesi (LC50 = 11.2 mg L–1) > Chrysoperla asoralis (LC50 = 29 mg L–1) > Trichogramma pretiosum (LC50 = 32.9 mg L–1) > Ceraeochrysa cincta (LC50 = 94.4 mg L–1) > Orius insidious (LC50 = 304 mg L–1) > Telenomus remus (LC50 = 364 mg L–1) > Heleobia cumingii (LC50 = 10,669 mg L–1). Considering eggs hatching, C. asoralis was more sensible than C. cincta. For T. pretiosum and T. fuentesi were observed effects on adult’s emergency since 160 and 800 mg As L–1, respectively. From these results, environmental risk assessment (ERA) of this insecticide was calculated. Risk quotient (RQ) indicated in all cases, that lead arseniate is highly risky to environment.
Agricultural Pesticides Mixtures Use and Its Toxicological Implications in Health
Authors: Castro Vera Lúcia Scherholz Salgado de
Published: June 2010

The use of pesticides mixtures is relatively a common practice in agriculture. The human health may be affected by pesticides directly, through environmental contamination or rural areas proximity. Exposure to pesticides mixtures, like herbicides as sulfentrazone and atrazine or fungicides as triazole and estrobilurin, may cause reproductive toxicity and/or damage on the animal development of the exposed organisms since they have potential as endocrine disruptors. This exposure may also cause health damage on rural workers. In this way, it is important to establish the pesticides mixtures levels that are able to cause harmful effects on non-target organisms. These facts show the necessity of experimental studies related to concomitant  pesticide exposure and ameliorate its methodology. These methodologies may predict the conditions under which the interactions may occur. The comprehension of the mixtures definition and the development of its estimative may be useful  tools to determine the pesticide mixture use, advantages and disadvantages. Therefore, there is the necessity of building an  agriculture that considers social, economic and environmental aspects.
Study of spatiotemporal variation of atmospheric mercury and its human exposure around an integrated steel plant, India
Authors: Pervez S. , Koshle A. , Pervez Y.
Published: June 2010

Abstract. Mercury release by coal combustion has been significantly increased in India. Mercury content in coal has been analyzed to 0.272 ppm by Central Pollution Control Board. Toxicological effects of elemental Hg (Hg0) exposure include respiratory and renal failures, cardiac arrest, and cerebral oedema, while subclinical exposure may induce kidney, behavioral, and cognitive dysfunctions. The present work is focused on dispersion pattern and inter-phase exchange phenomena of ambient mercury between air-particulate matter evaluations of alongwith dominance of various major routes of human exposure-dose response using regression analysis around an integrated steel plant in central India. Source-downwind type stratified random sampling plan using longitudinal study design has been adopted for ambient monitoring of total mercury, while representative sampling plant has been adopted for persona exposure-dose response study In space-time framework. Control sites and subjects have been chosen from uncontaminated area (100 km away from any industrial activities). 06 ambient air monitoring stations and 17 subjects from workers, non-workers but local residents' categories and from controlled sites have been chosen for the study. Samples of mercury biomarkers (blood, breast milk and urine) have also been collected from same subjects in each month during sampling period. The sampling period was March 2005 to February 2006 . Samples of 30% acidified KMnO4 for air-Hg absorption, PM10, RPM and biological samples were analyzed for total mercury by ICP-AES using standard methods. Local soils and ground water were also monitored for total mercury content during the sampling period. Results have shown that mercury concentration is very high compared to prescribed limits in all receptors. Results of exchange phenomenon have shown the higher transfer of mercury from air to particulate during combustion in steel plant environment due to presence of huge amount of iron particles, in contrast to results obtained in other industrial locations earlier. Plant workers have shown 1.5 to 2.5 times higher personal RPM-Hg levels compared to Category 2 and 20–30 times higher than Category 3. All biomarkers have shown higher Hg presence compared to prescribed standards. Regression analysis between exposure routes and bio-receptors has been investigated. Dominance status of selected routes of bio-accumulation has been varied from category to category.
Chemical evolution of secondary organic aerosol from OH-initiated heterogeneous oxidation
Authors: George I. J. , Abbatt J. P. D.
Published: June 2010

Abstract. The heterogeneous oxidation of laboratory Secondary Organic Aerosol (SOA) particles by OH radicals was investigated. SOA particles, produced by reaction of α-pinene and O3, were exposed to OH radicals in a flow tube, and particle chemical composition, size, and hygroscopicity were measured to assess modifications due to oxidative aging. Aerosol Mass Spectrometer (AMS) mass spectra indicated that the degree of oxidation of 200 nm diameter SOA particles was significantly enhanced due to OH-initiated oxidation, as evidenced by the increase in the fraction of m/z 44 fragment of total organic mass concentration (F44). F44 values of the SOA particles, initially in the range F44=0.04–0.07, increased by up to ΔF44~0.01 under equivalent atmospheric aging timescales of 2 weeks, assuming a 24-h average OH concentration of 106 cm−3. Particle O/C ratios calculated from F44 values, initially in the range O/C=0.25–0.35, rose by a maximum of ΔO/C~0.04 units for 2 weeks of aging. Particle densities also increased with heterogeneous oxidation, consistent with the observed increase in the degree of oxidation. Minor reductions in particle size, with volume losses of up to 10%, were observed due to volatilization of oxidation products. The SOA particles activated more readily to form cloud droplets with an increase in the κ hygroscopicity parameter of up to a factor of two for the equivalent of 2 weeks of OH atmospheric exposure. These results indicate that OH heterogeneous oxidation of typical SOA needs to be considered as an atmospheric organic aerosol aging mechanism, most likely of higher relative importance away from VOC source regions, where other aging mechanisms are less dominant.
Quantifying the clear-sky temperature inversion frequency and strength over the Arctic Ocean during summer and winter seasons from AIRS profiles
Authors: Devasthale A. , Willén U. , Karlsson K.-G. , Jones C. G.
Published: June 2010

Abstract. Temperature inversions are one of the dominant features of the Arctic atmosphere and play a crucial role in various processes by controlling the transfer of mass and moisture fluxes through the lower troposphere. It is therefore essential that they are accurately quantified, monitored and simulated as realistically as possible over the Arctic regions. In the present study, the characteristics of inversions in terms of frequency and strength are quantified for the entire Arctic Ocean for summer and winter seasons of 2003 to 2008 using the AIRS data for the clear-sky conditions. The probability density functions (PDFs) of the inversion strength are also presented for every summer and winter month. Our analysis shows that although the inversion frequency along the coastal regions of Arctic decreases from June to August, inversions are still seen in almost each profile retrieved over the inner Arctic region. In winter, inversions are ubiquitous and are also present in every profile analysed over the inner Arctic region. When averaged over the entire study area (70° N–90° N), the inversion frequency in summer ranges from 69 to 86% for the ascending passes and 72–86% for the descending passes. For winter, the frequency values are 88–91% for the ascending passes and 89–92% for the descending passes of AIRS/AQUA. The PDFs of inversion strength for the summer months are narrow and right-skewed (or positively skewed), while in winter, they are much broader. In summer months, the mean values of inversion strength for the entire study area range from 2.5 to 3.9 K, while in winter, they range from 7.8 to 8.9 K. The standard deviation of the inversion strength is double in winter compared to summer. The inversions in the summer months of 2007 were very strong compared to other years. The warming in the troposphere of about 1.5–3.0 K vertically extending up to 400 hPa was observed in the summer months of 2007.
Nitrogen oxides and PAN in plumes from boreal fires during ARCTAS-B and their impact on ozone: an integrated analysis of aircraft and satellite observations
Authors: Alvarado M. J. , Logan J. A. , Mao J. , Apel E. , Riemer D. , Blake D. , Cohen R. C. , Min K.-E. , Perring A. E. , Browne E. C. , Wooldridge P. J. , Diskin G. S. , Sachse G. W. , Fuelberg H. , Sessions W. R. , Harrigan D. L. , Huey G. , Liao J. , Case-Hanks A. , Jimenez J. L. , Cubison M. J. , Vay S. A. , Weinheimer A. J. , Knapp D. J. , Montzka D. D. , Flocke F. M. , Pollack I. B. , Wennberg P. O. , Kurten A. , Crounse J. , Clair J. M. St. , Wisthaler A. , Mikoviny T. , Yantosca R. M. , Carouge C. C. , Le Sager P.
Published: June 2010

Abstract. We determine enhancement ratios for NOx, PAN, and other NOy species from boreal biomass burning using aircraft data obtained during the ARCTAS-B campaign and examine the impact of these emissions on tropospheric ozone in the Arctic. We find an initial emission factor for NOx of 1.06 g NO per kg dry matter (DM) burned, much lower than previous observations of boreal plumes, and also one third the value recommended for extratropical fires. Our analysis provides the first observational confirmation of rapid PAN formation in a boreal smoke plume, with 40% of the initial NOx emissions being converted to PAN in the first few hours after emission. We find little clear evidence for ozone formation in the boreal smoke plumes during ARCTAS-B in either aircraft or satellite observations, or in model simulations. Only a third of the smoke plumes observed by the NASA DC8 showed a correlation between ozone and CO, and ozone was depleted in the plumes as often as it was enhanced. Special observations from the Tropospheric Emission Spectrometer (TES) also show little evidence for enhanced ozone in boreal smoke plumes between 15 June and 15 July 2008. Of the 22 plumes observed by TES, only 4 showed ozone increasing within the smoke plumes, and even in those cases it was unclear that the increase was caused by fire emissions. Using the GEOS-Chem atmospheric chemistry model, we show that boreal fires during ARCTAS-B had little impact on the median ozone profile measured over Canada, and had little impact on ozone within the smoke plumes observed by TES.
The sensitivity of secondary organic aerosol component partitioning to the predictions of component properties – Part 1: A systematic evaluation of some available estimation techniques
Authors: McFiggans G. , Topping D. O. , Barley M. H.
Published: June 2010

Abstract. A large number of calculations of the absorptive partitioning of organic compounds have been made using a number of methods to predict the component vapour pressures, p0, and activity coefficients, γi, required in the calculations. The sensitivities of the predictions in terms of the condensed component masses, volatility, O:C ratio, molar mass and functionality distributions to the choice of p0 and γi models and to the number of components to represent the organic mixture have been systematically compared. The condensed component mass was found to be highly sensitive to the vapour pressure model, and less sensitive to both the activity coefficient model and the number of components used to represent the mixture although the sensitivity to the change in property estimation method increased substantially with increased simplification in the treatment of the organic mixture. This was a general finding and was also clearly evident in terms of the predicted component functionality, O:C ratio, molar mass and volatility distributions of the condensed organic components. Within the limitations of the study, this clearly demonstrates the requirement for more accurate representation of the p0 and γi of the semi-volatile organic proxy components used in simplified models as the degree of simplification increases. This presents an interesting paradox, since such reduction in complexity necessarily leads to divergence from the complex behaviour of real multicomponent atmospheric aerosol.
Combined use of FORMOSAT-2 images with a crop model for biomass and water monitoring of permanent grassland in Mediterranean region
Authors: Courault D. , Hadria R. , Ruget F. , Olioso A. , Duchemin B. , Hagolle O. , Dedieu G.
Published: June 2010

Abstract. The aim of this study is to propose methods to improve crop and water management in Mediterranean regions. At landscape scale, there is a very large spatial variability of agricultural practices, particularly for grasslands irrigated by flooding. These grasslands are harvested three times per year and produce high quality hay, but their productions decreased significantly these last few years because of the water scarcity. It is therefore important to assess the real water requirement for crops in order to predict productions in the case of agricultural practice modifications. Until now, the spatial variability of agricultural practices was obtained through surveys from farmers, but this method was tedious to describe an entire region. Thus, the specific aim of the study is to propose a new approach based on: 1) the feasibility of using optical remote sensing data acquired at high spatio-temporal resolutions for agricultural practice monitoring and, 2) the evaluation of a crop model, forced with this data, for estimating water balance and crop yield. We developed a methodology based on the combined use of FORMOSAT-2 images and STICS crop model to estimate production, evapotranspiration and drainage of irrigated grasslands in "the Crau" region in the South Eastern France. Numerous surveys and ground measurements were performed during an experiment conducted in 2006. Simple algorithms were developed to retrieve the dynamic of Leaf Area Index (LAI) for each plot and the main agricultural practices such as mowing and irrigation dates. This information was then used to parameterize STICS, applied at region scale to estimate the spatial variability of water budget associated with the biomass productions. Results are displayed at the farm scale. Satisfactory results were obtained when compared to ground measurements. The method for extrapolation to other regions or crops is discussed as regard to data available.
A Closer Look Inside Nanotubes: Pore Structure Evaluation of Anodized Alumina Templated Carbon Nanotube Membranes Through Adsorption and Permeability Studies
Authors: Pilatos Georgios , Vermisoglou Eleni C. , Romanos Georgios E. , Karanikolos Georgios N. , Boukos Nikos , Likodimos Vlassis , Kanellopoulos Nick K.
Published: June 2010

Although hollow nanostructures, such as nanotubes, represent a major portion of nanoscaled materials with a tremendously large application range, a detailed evaluation of their internal characteristics still remains elusive. Transmission electron microscopy is the most common analytical technique to examine the internal configuration of these structures, yet it can only provide evidence of a minimal portion of the overall material, thus, it cannot be accurately generalized. In the present paper, in addition to electron microscopy and other spot‐size analysis methods (X‐ray diffraction, Raman spectroscopy, etc.), a combination of techniques including adsorption, permeability, and relative permeability are employed in order to provide important insights into various crucial details of the overall internal surface and hollow‐space characteristics of carbon nanotube (CNT) arrays and membranes. The CNT arrays are fabricated using anodized alumina as a template in a flow‐through chemical vapor deposition (CVD) reactor. This is the first systematic approach for investigating the internal configuration of template‐based CNT arrays in detail. Key findings are made for the customized optimization of the resulting nanotube membranes for a variety of applications, including separations, nanofluidics and nanoreactors, biological capturing and purification, and controlled drug delivery and release.
A Concept in Bactericidal Materials: The Entrapment of Chlorhexidine within Silver
Authors: Ben‐Knaz Racheli , Pedahzur Rami , Avnir David
Published: June 2010

A new concept in bactericidal agents is described: the entrapment of an organic biocidal agent within a bactericidal metal, which leads to synergism between the two components. Specifically this concept is demonstrated for the entrapment of chlorhexidine digluconate (CHD) within an aggregated silver matrix, a metal known for its own biocidal qualities, forming the CHD@silver composite. The bactericidal efficacy against E. coli is evaluated and compared with the separate components. While the bactericidal efficacy of the individual ingredients (CHD and metallic silver) is very low, CHD@silver exhibits a markedly enhanced efficacy. This enhanced bactericidal effect is partially attributed to the simultaneous release and presence of the active biocidal ingredients CHD and Ag+ in the solution. Detailed composite characterization is provided.
Impaired activation‐induced cell death promotes spontaneous arthritis in antigen (cartilage proteoglycan)–specific T cell receptor–transgenic mice
Authors: Boldizsar Ferenc , Kis‐Toth Katalin , Tarjanyi Oktavia , Olasz Katalin , Hegyi Akos , Mikecz Katalin , Glant Tibor T.
Published: June 2010

Objective

To investigate whether genetic preponderance of a T cell receptor (TCR) recognizing an arthritogenic peptide of human cartilage proteoglycan (PG) is sufficient for development of arthritis.

Methods

We performed a longitudinal study using BALB/c mice expressing a TCR that recognizes the arthritogenic ATEGRVRVNSAYQDK peptide of human cartilage PG. PG‐specific TCR–transgenic (PG‐TCR–Tg) mice were inspected weekly for peripheral arthritis until 12 months of age. Peripheral joints were examined histologically, and T cell responses, T cell activation markers, serum cytokines, and autoantibodies were measured. Apoptosis and signaling studies were performed in vitro on T cells from aged PG‐TCR–Tg mice.

Results

Spontaneous arthritis developed as early as 5–6 months of age, and the incidence increased to 40–50% by 12 months of age. Progressive inflammation began with cartilage and bone erosions in the interphalangeal joints, and later expanded to the proximal joints of the front and hind paws. Spontaneous arthritis was associated with a high proportion of activated CD4+ T cells, enhanced interferon‐γ and interleukin‐17 (IL‐17) production, and elevated levels of serum autoantibodies. PG‐TCR–Tg mice lacking IL‐4 developed arthritis earlier and at a higher incidence than IL‐4–sufficient mice. Antigen‐specific activation–induced cell death was diminished in vitro in CD4+ T cells of PG‐TCR–Tg mice with spontaneous arthritis, especially in those lacking IL‐4.

Conclusion

The presence of CD4+ T cells expressing a TCR specific for an arthritogenic PG epitope is sufficient to trigger spontaneous autoimmune inflammation in the joints of BALB/c mice. IL‐4 appears to be a negative regulator of this disease, through attenuation of activation‐induced cell death.
Adiponectin‐mediated changes in effector cells involved in the pathophysiology of rheumatoid arthritis
Authors: Frommer Klaus W. , Zimmermann Birgit , Meier Florian M. P. , Schröder Dirk , Heil Matthias , Schäffler Andreas , Büchler Christa , Steinmeyer Jürgen , Brentano Fabia , Gay Steffen , Müller‐Ladner Ulf , Neumann Elena
Published: June 2010

Objective

Rheumatoid arthritis (RA) is associated with increased production of adipokines, which are cytokine‐like mediators that are produced mainly in adipose tissue but also in synovial cells. Since RA synovial fibroblasts (RASFs), lymphocytes, endothelial cells, and chondrocytes are key players in the pathophysiology of RA, this study was undertaken to analyze the effects of the key adipokine adiponectin on proinflammatory and prodestructive synovial effector cells.

Methods

Lymphocytes were activated in part prior to stimulation. All cells were stimulated with adiponectin, and changes in gene and protein expression were determined by Affymetrix and protein arrays. Messenger RNA and protein levels were confirmed using semiquantitative reverse transcription–polymerase chain reaction (PCR), real‐time PCR, and immunoassays. Intracellular signal transduction was evaluated using chemical signaling inhibitors.

Results

Adiponectin stimulation of human RASFs predominantly induced the secretion of chemokines, as well as proinflammatory cytokines, prostaglandin synthases, growth factors, and factors of bone metabolism and matrix remodeling. Lymphocytes, endothelial cells, and chondrocytes responded to adiponectin stimulation with enhanced synthesis of cytokines and various chemokines. Additionally, chondrocytes released increased amounts of matrix metalloproteinases. In RASFs, adiponectin‐mediated effects were p38 MAPK and protein kinase C dependent.

Conclusion

Our previous findings indicated that adiponectin was present in inflamed synovium, at sites of cartilage invasion, in lymphocyte infiltrates, and in perivascular areas. The findings of the present study indicate that adiponectin induces gene expression and protein synthesis in human RASFs, lymphocytes, endothelial cells, and chondrocytes, supporting the concept of adiponectin being involved in the pathophysiologic modulation of RA effector cells. Adiponectin promotes inflammation through cytokine synthesis, attraction of inflammatory cells to the synovium, and recruitment of prodestructive cells via chemokines, thus promoting matrix destruction at sites of cartilage invasion.
Reference standards and reference multipliers for the comparison of the citation impact of papers published in different time periods
Authors: Marx Werner , Bornmann Lutz , Cardona Manuel
Published: June 2010

In this study, reference standards and reference multipliers are suggested as a means to compare the citation impact of earlier research publications in physics (from the period of “Little Science” in the early 20th century) with that of contemporary papers (from the period of “Big Science,” beginning around 1960). For the development of time‐specific reference standards, the authors determined (a) the mean citation rates of papers in selected physics journals as well as (b) the mean citation rates of all papers in physics published in 1900 (Little Science) and in 2000 (Big Science); this was accomplished by relying on the processes of field‐specific standardization in bibliometry. For the sake of developing reference multipliers with which the citation impact of earlier papers can be adjusted to the citation impact of contemporary papers, they combined the reference standards calculated for 1900 and 2000 into their ratio. The use of reference multipliers is demonstrated by means of two examples involving the time adjusted h index values for Max Planck and Albert Einstein.
Spectro‐polarimetry in the era of large solar telescopes
Authors: Socas‐Navarro H.
Published: June 2010

This paper discusses some of the challenges of spectro‐polarimetric observations with a large aperture solar telescope such as the ATST or the EST. The observer needs to reach a compromise between spatial and spectral resolution, time cadence, and signal‐to‐noise ratio, as only three of those four parameters can be pushed to the limit. Tunable filters and grating spectrographs provide a natural compromise as the former are more suitable for high‐spatial resolution observations while the latter are a better choice when one needs to work with many wavelengths at full spectral resolution. Given the requirements for the new science targeted by these facilities, it is important that 1) tunable filters have some multi‐wavelength capability; and 2) grating spectrographs have some 2D field of view (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
IR spectroscopy of COmosphere dynamics with the CO ?rst overtone band
Authors: Schad T.A. , Penn M.J.
Published: June 2010

We discuss observations of the weak ?rst overtone (Δν = 2) CO absorption band near 2300 nm with the U.S. National Solar Observatory Array Camera (NAC), a modern mid‐infrared detector. This molecular band provides a thermal diagnostic that forms lower in the atmosphere than the stronger fundamental band near 4600 nm. The observed center‐to‐limb increase in CO line width qualitatively agrees with the proposed higher temperature shocks or faster plasma motions higher in the COmosphere. The spatial extent of chromospheric shock waves is currently at or below the diffraction limit of the available CO lines at existing telescopes. Five minute period oscillations in line strength and measured Doppler shifts are consistent with the p‐mode excitation of the photospheric gas. We also show recent efforts at direct imaging at 4600 nm. We stress that future large‐aperture solar telescopes must be teamed with improved, dynamic mid‐infrared instruments, like the NAC, to capitalize on the features that motivate such facilities (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
SUNRISE – Impressions from a successful science flight
Authors: Schmidt W. , Solanki S.K. , Barthol P. , Berkefeld T. , Gandorfer A. , Knölker M. , Martínez Pillet V. , Schüssler M. , Title A.
Published: June 2010

SUNRISE is a balloon‐borne telescope with an aperture of one meter. It is equipped with a filter imager for the UV wavelength range between 214 nm and 400 nm (SUFI), and with a spectro‐polarimeter that measures the magnetic field of the photosphere using the Fe I line at 525.02 nm that has a Landé factor of 3. SUNRISE performed its first science flight from 8 to 14 June 2009. It was launched at the Swedish ESRANGE Space Center and cruised at an altitude of about 36 km and geographic latitudes between 70 and 74 degrees to Somerset Island in northern Canada. There, all data, the telescope and the gondola were successfully recovered. During its flight, Sunrise achieved high pointing stability during 33 hours, and recorded about 1.8 TB of science data. Already at this early stage of data processing it is clear that SUNRISE recorded UV images of the solar photosphere, and spectropolarimetric measurements of the quiet Sun's magnetic field of unprecedented quality (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The NST: First results and some lessons for ATST and EST
Authors: Goode P.R. , Coulter R. , Gorceix N. , Yurchyshyn V. , Cao W.
Published: June 2010

In January 2009, first light observations with the NST (New Solar Telescope) in Big Bear Solar Observatory (BBSO) were made. NST has a 1.7 m primary with a 1.6 m clear aperture. First observational results in TiO and Hαare shown and discussed. The NST primary mirror is the most aspheric telescope mirror deployed to date. The NST is early in its commissioning, and the plans for this phase will be sketched. Lessons learned in building and implementing the NST are germane for the ATST and EST telescopes and will be discussed. The NST has an off‐axis Gregorian configuration consisting of a parabolic primary, heat‐stop, elliptical secondary and diagonal flats. The focal ratio of the primary mirror is f/2.4. The working wavelength range covers from 0.4 to 1.7 µm in the Coudé Lab beneath the telescope and all wavelengths including the far infrared at the Nasmyth focus on the dome floor (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
GREGOR solar telescope: Design and status
Authors: Volkmer R. , von der Lühe O. , Denker C. , Solanki S.K. , Balthasar H. , Berkefeld T. , Caligari P. , Collados M. , Fischer A. , Halbgewachs C. , Heidecke F. , Hofmann A. , Klvaňa M. , Kneer F. , Lagg A. , Popow E. , Schmidt D. , Schmidt W. , Sobotka M. , Soltau D. , Strassmeier K.G.
Published: June 2010

The integration and verification phase of the GREGOR telescope reached an important milestone with the installation of the interim 1 m SolarLite primary mirror. This was the first time that the entire light path had seen sunlight. Since then extensive testing of the telescope and its subsystems has been carried out. The integration and verification phase will culminate with the delivery and installation of the final 1.5 m Zerodur primary mirror in the summer of 2010. Observatory level tests and science verification will commence in the second half of 2010 and in 2011. This phase includes testing of the main optics, adaptive optics, cooling and pointing systems. In addition, assuming the viewpoint of a typical user, various observational modes of the GREGOR Fabry‐Pérot Interferometer (GFPI), the Grating Infrared Spectrograph (GRIS), and high‐speed camera systems will be tested to evaluate if they match the expectations and science requirements. This ensures that GREGOR will provide high‐quality observations with its combination of (multi‐conjugate) adaptive optics and advanced post‐focus instruments. Routine observations are expected for 2012 (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Instrument and data analysis challenges for imaging spectropolarimetry
Authors: Denker C.
Published: June 2010

The next generation of solar telescopes will enable us to resolve the fundamental scales of the solar atmosphere, i.e., the pressure scale height and the photon mean free path. High‐resolution observations of small‐scale structures with sizes down to 50 km require complex post‐focus instruments, which employ adaptive optics (AO) and benefit from advanced image restoration techniques. The GREGOR Fabry‐Pérot Interferometer (GFPI) will serve as an example of such an instrument to illustrate the challenges that are to be expected in instrumentation and data analysis with the next generation of solar telescopes (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Compressed sensing for next generation instruments
Authors: Asensio Ramos A.
Published: June 2010

This document discusses the possibility of using compressed sensing techniques for measuring 2D spectro‐polarimetric information using only one etalon and a broad prefilter. Instead of using an etalon and an extremely narrow prefilter (with all the subsequent problems of alignment), the idea is to use multiplexing techniques to include in the observations all the secondary peaks of the etalon. The reconstruction of the signal is done under the assumption that it can be efficiently reproduced in an orthogonal basis set (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Animation‐based learning of map projections in geomatics engineering
Authors: Beşdok Erkan , Geymen Abdurrahman , Özkan Coşkun , Palancıoğlu H. Mustafa
Published: June 2010

Using educational animations is a very effective way of conveying the knowledge and increasing the understanding in a lecture. Teaching and learning of map projections are among the most difficult topics in the education of Geomatics Engineering for both lecturers and students. In this article, it is aimed to visualize the mapping projections with educational animations developed with Matlab Mapping toolbox to provide better understanding of students in the Geomatics Engineering. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 20: 666–672, 2012
Interactive software application for calculation of non‐stationary heat conduction in a cylindrical body
Authors: Janáčová Dagmar , Charvátová Hana , Kolomazník Karel , Fialka Miloslav , Mokrejš Pavel , Vašek Vladimír
Published: June 2010

In this paper we present software application used for the study of heat transfer problems that is a part of education of subject Process Engineering taught at the Tomas Bata University in Zlín. The application speeds up calculation of non‐stationary heat conduction and visualizes temperature distribution in the cylindrical body. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 21: 89–94, 2013
DSP‐based real‐time platform for remote control of internet‐connected systems
Authors: Peñaloza‐Mejía O. , Márquez‐Martínez L. A. , Alvarez‐Gallegos Ja. , Estrada‐García H. J.
Published: June 2010

This work presents the development of an experimental platform for remote control of Internet‐connected systems. The aim is to describe and to evaluate this platform, which exhibits some interesting peculiarities w.r.t. the mainstream literature: real‐time support over the Internet, capacity to handle loss/disorder of packets, and varying delays. Practical tests are given to show its capabilities to telecontrol different systems. The evaluation is carried out comparing the performance of some controllers for position coordination of a pair of local–remote Internet‐connected systems. Besides, an assessment of platform usage and learning effectiveness was developed to conclude on its pedagogical viability in engineering education. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 21: 203–213, 2013
Site‐Directed Mutagenesis of Rice Serine Racemase: Evidence That Glu219 and Asp225 Mediate the Effects of Mg2+ on the Activity
Authors: Gogami Yoshitaka , Kobayashi Ai , Ikeuchi Toshihiko , Oikawa Tadao
Published: June 2010

We succeeded in constructing the Glu219Ala/Asp225Ala (i.e., E219A/D225A) serine racemase (SerR) by site‐directed mutagenesis, and the effects of Mg2+ on the catalytic efficiency and the structure were compared between the E219A/D225A‐SerR and the wild‐type protein. This is the first example of a serine racemase whose amino acid residues in the Mg2+‐binding site were replaced with other amino acids by site‐directed mutagenesis. Neither the serine racemase nor the dehydratase activities of the E219A/D225A‐SerR were affected by the addition of Mg2+, and Glu219 and Asp225 of the SerR are the essential amino acid residues for Mg2+ to affect both kinds of enzyme activities. Therefore, Glu219 and Asp225 mediate the effects of Mg2+ on the activity and are important for the SerR to form the Mg2+‐binding site. Judging from the difference of the Keq values between the E219A/D225A‐SerR and the SerR, Mg2+ might affect the equilibrium states in the racemase reaction. The fluorescence quenching analysis of the E219A/D225A‐SerR showed that Mg2+ bound to Glu219 and Asp225 of the SerR probably causes a conformational change in the ternary structure of the SerR.
Detection and Function of the Intramolecular Disulfide Bond in Arginine Racemase: An Enzyme with Broad Substrate Specificity
Authors: Matsui Daisuke , Oikawa Tadao
Published: June 2010

We found that a single intramolecular disulfide bond between the cysteines C47 and C73 exists in the primary structure of arginine racemase (ArgR) from Pseudomonas taetrolens NBRC 3460, and this is the first example of a pyridoxal phosphate (PLP)‐dependent amino acid racemase that contains a disulfide bond. The amino acid racemase activity was still detected, when the disulfide bond of ArgR was disrupted by site‐directed mutagenesis or reduced with dithiothreitol (DTT). The thermal and pH profiles and the quaternary structure of ArgR did not change when the disulfide bond of ArgR was disrupted by site‐directed mutagenesis. The substrate specificity and the overall structure did not change when the disulfide bond of ArgR was reduced with DTT after the protein was matured. However, these properties changed when the disulfide bond of ArgR was disrupted by site‐directed mutagenesis before protein maturation. The total activity of ArgR decreased when the disulfide bond of ArgR was disrupted by site‐directed mutagenesis before the protein was matured or when ArgR was expressed in the cytoplasm. Based on these results, we can conclude that the disulfide bond of ArgR is essential for ArgR to fold and mature as an amino acid racemase with broad substrate specificity.
Indispensable but Insufficient Role of RenalD‐Amino Acid Oxidase in Chiral Inversion ofNG‐Nitro‐D‐arginine
Authors: Xin Yan‐Fei , Li Xin , Hao Bin , Gong Nian , Sun Wen‐Qiang , Konno Ryuichi , Wang Yong‐Xiang
Published: June 2010

Unidirectionally chiral inversion ofNG‐nitro‐D‐arginine (D‐NNA) to itsL‐enantiomer (L‐NNA) occurred in rats, and it was blocked markedly (ca.80%) by renal vascular ligation, and entirely (100%) by theD‐amino acid oxidase (DAO) inhibitor sodium benzoate, suggesting that renal DAO is essential for the inversion. However, the doses of sodium benzoate administrated were extremely high (e.g., 400 mg/kg) due to its low potency. It is thus possible that sodium benzoate‐mediated blockade ofD‐NNA inversion might be due to its nonspecific (or non‐DAO‐related) effects. In addition, afterD‐NNA was incubated with the pure enzyme of DAOin vitrowithout tissue homogenates,L‐NNA was not produced, even thoughD‐NNA was disposed. We propose that this occurred becauseD‐NNA was first converted to its correspondingα‐keto acid by DAO and then toL‐NNA by transaminase(s); however, there was no direct evidence for this process. The goal of this study is to further elucidate the process ofD‐NNA chiral inversion bothin vivoand inin vitrotissue homogenates by comparing mutant ddY/DAO−/−mice that lack DAO activity entirely compared to normal ddY/DAO+/+mice and Swiss mice. Furthermore, the ability to produceL‐NNA fromD‐NNA‐correspondingα‐keto acids (NG‐nitroguanidino‐2‐oxopentanoic acid) produced by porcine kidney‐derived DAO (pkDAO) was also studied in the DAO inhibitor‐pretreated rats. We found thatD‐NNA chiral inversion occurred in Swiss mice and ddY/DAO+/+mice bothin vivoand inin vitrokidney homogenates, but not in ddY/DAO−/−mice, correlated to their DAO activities. Theα‐keto acid (NG‐nitro‐guanidino‐2‐oxopentanoic acid) fromD‐NNA was able to produceL‐NNA, and subsequent vasoconstriction and pressor responses. These results indicate that the role of renal DAO is indispensible but insufficient for chiral inversion ofD‐NNA and other neutral and polarD‐amino acids, and unidentified aminotransferase(s) are involved in a subsequent mechanism for the process of chiral inversion.