bluuebunny/crossref_metadata_2025 huggingface dataset:
Tropospheric NO2 vertical column densities over Beijing: results of the first three years of ground-based MAX-DOAS measurements (2008–2011) and satellite validation
Authors: Ma J. Z. , Beirle S. , Jin J. L. , Shaiganfar R. , Yan P. , Wagner T.
Published: February 2013

Abstract. Ground-based measurements of scattered sunlight by the Multi Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) have been carried out at an urban site (39.95° N, 116.32° E) in Beijing megacity since 6 August 2008. In this study, we retrieved the tropospheric NO2 vertical column densities (VCDs) over Beijing from these MAX-DOAS observations from August 2008 to September 2011. Over this period, the daytime (08:00–17:00 Beijing Time (BJT, which equals UTC + 8)) mean tropospheric NO2 VCDs varied from 0.5 to 13.3 with an average of 3.6 during summertime, and from 0.2 to 16.8 with an average of 5.8 during wintertime, all in units of 1016 molecules cm−2. The average diurnal variation patterns of tropospheric NO2 over Beijing appeared to be rather different from one season to another, indicating differences in the emission strength and atmospheric lifetime. In contrast to previous studies, we find a small weekly cycle of the tropospheric NO2 VCD over Beijing. The NO2 VCD in the late afternoon was the largest on Saturday and the lowest on Sunday, and in the morning it reached a clear maximum on Wednesday. We also find a post-Olympic Games effect, with 39–54% decrease in the tropospheric NO2 VCD over Beijing estimated for August of 2008, compared to the following years. The tropospheric NO2 VCDs derived by our ground MAX-DOAS measurements show a good correlation with SCIAMACHY and OMI satellite data. However, compared with the MAX-DOAS measurements, the satellite observations underestimate the tropospheric NO2 VCDs over Beijing systematically, by 43% for SCIAMACHY and 26–38% for OMI (DOMINO v2.0 and DOMINO v1.02). Based on radiative transfer simulations, we show that the aerosol shielding effect can explain this underestimation, while the gradient smoothing effect caused by the coarse spatial resolution of the satellite observations could play an additional role.
Sources of anions in aerosols in northeast Greenland during late winter
Authors: Fenger M. , Sørensen L. L. , Kristensen K. , Jensen B. , Nguyen Q. T. , Nøjgaard J. K. , Massling A. , Skov H. , Becker T. , Glasius M.
Published: February 2013

Abstract. The knowledge of climate effects of atmospheric aerosols is associated with large uncertainty, and a better understanding of their physical and chemical properties is needed, especially in the Arctic environment. The objective of the present study is to improve our understanding of the processes affecting the composition of aerosols in the high Arctic. Therefore size-segregated aerosols were sampled at a high Arctic site, Station Nord (Northeast Greenland), in March 2009 using a Micro Orifice Uniform Deposit Impactor. The aerosol samples were extracted in order to analyse three water-soluble anions: chloride, nitrate and sulphate. The results are discussed based on possible chemical and physical transformations as well as transport patterns. The total concentrations of the ions at Station Nord were 53–507 ng m−3, 2–298 ng m−3 and 535–1087 ng m−3 for chloride (Cl−), nitrate (NO3−) and sulphate (SO42−), respectively. The aerosols in late winter/early spring, after polar sunrise, are found to be a mixture of long-range transported and regional to local originating aerosols. Fine particles, smaller than 1 μm, containing SO42−, Cl− and NO3−, are hypothesized to originate from long-range transport, where SO42− is by far the dominating anion accounting for 50–85% of the analyzed mass. The analysis suggests that Cl− and NO3− in coarser particles (> 1.5 μm) originate from local/regional sources. Under conditions where the air mass is transported over sea ice at high wind speeds, very coarse particles (> 18 μm) are observed, and it is hypothesized that frost flowers on the sea ice are a source of the very coarse nitrate particles.
A centrifugal ice microtome for measurements of atmospheric CO2 on air trapped in polar ice cores
Authors: Bereiter B. , Stocker T. F. , Fischer H.
Published: February 2013

Abstract. For atmospheric CO2 reconstructions using ice cores, the technique to release the trapped air from the ice samples is essential for the precision and accuracy of the measurements. We present here a new dry extraction technique in combination with a new gas analytical system that together show significant improvements with respect to current systems. Ice samples (3–15 g) are pulverised using a novel centrifugal ice microtome (CIM) by shaving the ice in a cooled vacuum chamber (−27 °C) in which no friction occurs due to the use of magnetic bearings. Both, the shaving principle of the CIM and the use of magnetic bearings have not been applied so far in this field. Shaving the ice samples produces finer ice powder and releases a minimum of 90% of the trapped air compared to 50%–70% when needle crushing is employed. In addition, the friction-free motion with an optimized design to reduce contaminations of the inner surfaces of the device result in a reduced system offset of about 2.0 ppmv compared to 4.9 ppmv. The gas analytical part shows a higher precision than the corresponding part of our previous system by a factor of two, and all processes except the loading and cleaning of the CIM now run automatically. Compared to our previous system, the complete system shows a 3 times better measurement reproducibility of about 1.1 ppmv (1 σ) which is similar to the best reproducibility of other systems applied in this field. With this high reproducibility, no replicate measurements are required anymore for most future measurement campaigns resulting in a possible output of 12–20 measurements per day compared to a maximum of 6 with other systems.
Retrieval interval mapping: a tool to visualize the impact of the spectral retrieval range on differential optical absorption spectroscopy evaluations
Authors: Vogel L. , Sihler H. , Lampel J. , Wagner T. , Platt U.
Published: February 2013

Abstract. Remote sensing via differential optical absorption spectroscopy (DOAS) has become a standard technique to identify and quantify trace gases in the atmosphere. Due to the wide range of measurement conditions, atmospheric compositions and instruments used, a specific challenge of a DOAS retrieval is to optimize the retrieval parameters for each specific case and particular trace gas of interest. Of these parameters, the retrieval wavelength range is one of the most important ones. Although for many trace gases the overall dependence of common DOAS retrieval on the evaluation wavelength interval is known, a systematic approach for finding the optimal retrieval wavelength range and quantitative assessment is missing. Here we present a novel tool to visualize the effect of different evaluation wavelength ranges. It is based on mapping retrieved column densities in the retrieval wavelength space and thus visualizing the consequences of different choices of spectral retrieval ranges caused by slightly erroneous absorption cross sections, cross correlations and instrumental features. Based on the information gathered, an optimal retrieval wavelength range may be determined systematically. The technique is demonstrated using examples of a theoretical study of BrO retrievals for stratospheric BrO and BrO measurements in volcanic plumes. However, due to the general nature of the tool, it is applicable to any type of DOAS retrieval (active or passive).
Simultaneous measurement of OI 557.7 nm, O2 (0, 1) Atmospheric Band and OH (6, 2) Meinel Band nightglow at Kolhapur (17° N), India
Authors: Parihar N. , Taori A. , Gurubaran S. , Mukherjee G. K.
Published: February 2013

Abstract. Near-simultaneous measurements of OI 557.7 nm, O2 (0, 1) Atmospheric Band and OH (6, 2) Meinel Band nightglow were carried out at Kolhapur (17° N), India during February–March 2007. Atmospheric temperatures around 87 and 94 km were derived from the knowledge of intensity measurements of spectral features OH (6, 2) Meinel Band and O2 Atmospheric Band, respectively. An account of the behaviour of derived temperatures has been presented. The nocturnal behaviour of OH and O2 temperatures is governed by the waves of tidal origin, whereas the signatures of planetary wave-like oscillations is noted in the night-to-night variation of two temperatures. This is probably the first report of planetary waves observed in nightglow temperatures from the Indian subcontinent.
Stoichiometry constrains microbial response to root exudation- insights from a model and a field experiment in a temperate forest
Authors: Drake J. E. , Darby B. A. , Giasson M.-A. , Kramer M. A. , Phillips R. P. , Finzi A. C.
Published: February 2013

Abstract. Plant roots release a wide range of chemicals into soils. This process, termed root exudation, is thought to increase the activity of microbes and the exoenzymes they synthesize, leading to accelerated rates of carbon (C) mineralization and nutrient cycling in rhizosphere soils relative to bulk soils. The nitrogen (N) content of microbial biomass and exoenzymes may introduce a stoichiometric constraint on the ability of microbes to effectively utilize the root exudates, particularly if the exudates are rich in C but low in N. We combined a theoretical model of microbial activity with an exudation experiment to test the hypothesis that the ability of soil microbes to utilize root exudates for the synthesis of additional biomass and exoenzymes is constrained by N availability. The field experiment simulated exudation by automatically pumping solutions of chemicals often found in root exudates ("exudate mimics") containing C alone or C in combination with N (C : N ratio of 10) through microlysimeter "root simulators" into intact forest soils in two 50-day experiments. The delivery of C-only exudate mimics increased microbial respiration but had no effect on microbial biomass or exoenzyme activities. By contrast, experimental delivery of exudate mimics containing both C and N significantly increased microbial respiration, microbial biomass, and the activity of exoenzymes that decompose low molecular weight components of soil organic matter (SOM, e.g., cellulose, amino sugars), while decreasing the activity of exoenzymes that degrade high molecular weight SOM (e.g., polyphenols, lignin). The modeling results were consistent with the experiments; simulated delivery of C-only exudates induced microbial N-limitation, which constrained the synthesis of microbial biomass and exoenzymes. Exuding N as well as C alleviated this stoichiometric constraint in the model, allowing for increased exoenzyme production, the priming of decomposition, and a net release of N from SOM (i.e., mineralization). The quantity of N released from SOM in the model simulations was, under most circumstances, in excess of the N in the exudate pulse, suggesting that the exudation of N-containing compounds can be a viable strategy for plant-N acquisition via a priming effect. The experimental and modeling results were consistent with our hypothesis that N-containing compounds in root exudates affect rhizosphere processes by providing substrates for the synthesis of N-rich microbial biomass and exoenzymes. This study suggests that exudate stoichiometry is an important and underappreciated driver of microbial activity in rhizosphere soils.
Implications of accounting for land use in simulations of ecosystem services and carbon cycling in Africa
Authors: Lindeskog M. , Arneth A. , Bondeau A. , Waha K. , Seaquist J. , Olin S. , Smith B.
Published: February 2013

Abstract. Dynamic global vegetation models (DGVMs) are important tools for modelling impacts of global change on ecosystem services. However, current models often do not take full account of human land management and land use and land cover changes (LULCC). We integrated croplands and their management and natural vegetation recovery and succession following land use abandonment into the LPJ-GUESS DGVM. The revised model was applied to Africa as a case study to investigate the implications of accounting for land use on agricultural production, net ecosystem carbon balance (NECB) and on the general skill of the model in reproducing trends and patterns in vegetation structure and function. The seasonality of modelled monthly fraction of absorbed photosynthetically active radiation (FPAR) was shown to agree well with satellite-inferred normalised difference vegetation index (NDVI). In regions with a large proportion of cropland, the managed land addition improved the FPAR vs. NDVI fit significantly. Modelled 1991–1995 average yields for the seven most important African crops, representing potential optimal yields limited only by climate forcings, were generally higher than reported FAO yields by a factor of 2–6, similar to previous yield gap estimates. Modelled inter-annual yield variations during 1971–2005 generally agreed well with FAO statistics, especially in regions with pronounced climate seasonality. Modelled land-atmosphere carbon fluxes for Africa associated with land use change (0.09 PgC yr−1 release to the atmosphere for the 1980s) agreed well with previous estimates. Cropland management options (residue removal, grass as cover crop) were shown to be of similar importance to the land-atmosphere carbon flux as land use change for the 20th century.
Autonomous distributed temperature sensing for long-term heated applications in remote areas
Authors: Kurth A.-M. , Dawes N. , Selker J. , Schirmer M.
Published: February 2013

Abstract. Distributed temperature sensing (DTS) is a fiber-optical method enabling simultaneous temperature measurements over long distances. Electrical resistance heating of the metallic components of the fiber-optic cable provides information on the thermal characteristics of the cable's environment, providing valuable insight into processes occurring in the surrounding medium, such as groundwater–surface water interactions, dam stability or soil moisture. Until now, heated applications required direct handling of the DTS instrument by a researcher, rendering long-term investigations in remote areas impractical due to the often difficult and time-consuming access to the field site. Remote control and automation of the DTS instrument and heating processes, however, resolve the issue with difficult access. The data can also be remotely accessed and stored on a central database. The power supply can be grid independent, although significant infrastructure investment is required here due to high power consumption during heated applications. Solar energy must be sufficient even in worst case scenarios, e.g. during long periods of intense cloud cover, to prevent system failure due to energy shortage. In combination with storage batteries and a low heating frequency, e.g. once per day or once per week (depending on the season and the solar radiation on site), issues of high power consumption may be resolved. Safety regulations dictate adequate shielding and ground-fault protection, to safeguard animals and humans from electricity and laser sources. In this paper the autonomous DTS system is presented to allow research with heated applications of DTS in remote areas for long-term investigations of temperature distributions in the environment.
Ground-penetrating radar insight into a coastal aquifer: the freshwater lens of Borkum Island
Authors: Igel J. , Günther T. , Kuntzer M.
Published: February 2013

Abstract. Freshwater lenses, as important resource for drinking water, are sensitive to climate changes and sea level rise. To simulate this impact on the groundwater systems, hydraulic subsurface models have to be designed. Geophysical techniques can provide information for generating realistic models. The aim of our work is to show how ground-penetrating radar (GPR) investigations can contribute to such hydrological simulations. In the pilot area, Borkum island, GPR was used to map the shape of the groundwater table (GWT) and to characterise the aquifer. In total, 20 km of constant offset (CO) profiles were measured with centre frequencies of 80 and 200 MHz. Wave velocities were determined by common midpoint (CMP) measurements and vertical radar profiling (VRP) in a monitoring well. The 80 MHz CO data show a clear reflection at the groundwater table, whereas the reflection is weaker for the 200 MHz data. After correcting the GPR water tables for the capillary rise, they are in good accordance with the pressure heads of the observation wells in the area. In the centre of the island, the groundwater table is found up to 3.5 m above sea level, however it is lower towards the coastline and marshland. Some local depressions are observed in the region of dune valleys and around pumping stations of the local water supplier. GPR also reveals details within the sediments and highly-permeable aeolian sands can be distinguished from less-permeable marine sediments. Further, a silt loam layer below the water table could be mapped on a large area. The reflection characteristics indicates scattered erosion channels in this layer that cause it to be an aquitard with some leakage. GPR provides a high resolution map of the groundwater table and insight into the stratigraphy of the sediments and their hydraulic properties. This is valuable complementary information to the observation of sparsely distributed monitoring wells as input to hydraulic simulation.
Resolving structural errors in a spatially distributed hydrologic model
Authors: Spaaks J. H. , Bouten W.
Published: February 2013

Abstract. In hydrological modeling, model structures are developed in an iterative cycle as more and different types of measurements become available and our understanding of the hillslope or watershed improves. However, with increasing complexity of the model, it becomes more and more difficult to detect which parts of the model are deficient, or which processes should also be incorporated into the model during the next development step. In this study, we use two methods (SCEM-UA and SODA) to calibrate a purposely deficient 3-D hillslope-scale model to error-free, artificially generated observations. We use a multi-objective approach based on distributed pressure head at the soil-bedrock interface and hillslope-scale discharge and water balance. SODA's usefulness as a diagnostic methodology is demonstrated by its ability to identify the timing and location of processes that are missing in the model. We further show that SODA's state updates provide information that could readily be incorporated into an improved model structure, and that this type of information cannot be gained from parameter estimation methods such as SCEM-UA. We conclude that SODA can help guide the discussion between experimentalists and modelers by providing accurate and detailed information on how to improve spatially distributed hydrologic models.
Review of unprecedented ULF electromagnetic anomalous emissions possibly related to the Wenchuan MS = 8.0 earthquake, on 12 May 2008
Authors: Li M. , Lu J. , Parrot M. , Tan H. , Chang Y. , Zhang X. , Wang Y.
Published: February 2013

Abstract. This work presents ground based ultra low frequency (ULF) electromagnetic field measurements in the frequency range 0.1–10 Hz from January 2007 to December 2008. In this time period a strong earthquake series hits the Wenchuan region with a main shock of magnitude MS = 8.0 on 12 May 2008. The Hebei ULF electromagnetic observation network includes eight observation stations in north China and the observation system named E-EM is employed to record the electric potential difference between two electrodes with an analog automatic real-time continuous pen recorder. First, weak electric signals appeared on 11 October 2007 at Ningjin station, most of which are with relative long periods ~0.4–3 s and unequal amplitudes ~0.5–20 mm. Then, similar signals appeared at Gaobeidian station at the end of October. Abnormal behavior with various time intervals appeared randomly and not every day. At the beginning of April 2008, one and a half months before the Wenchuan MS = 8.0 earthquake, the anomalies were gradually subject to an intensive increase mainly in Gaobeidian SN direction and Ningjin EW direction. The abnormal behavior appeared almost every day and the amplitudes of electric signals, with short periods of ~0.1–0.3 s, enhanced to ~3–30 mm. Qingxian station started to record marginally high frequency signals in SN and EW components in the middle of April. On 9 May, 3 days before the main shock, the amplitude of high frequency information increased sharply at the same time in two components at Gaobeidian station and the maximum amplitude was up to 70 mm, i.e. 1.3 mV m−1 for the electric field. This situation did not stop until 17 May, 5 days after the main event. However, this kind of climax phenomena did not happen at Ningjin station and Qingxian station. Then weak anomalous information lasted about four months again, and strong signals appeared again for a short time before several powerful aftershocks. It is the first time that an abnormity with so large an amplitude and so long a duration time in the observation history of this network though several strong earthquakes were recorded. Furthermore, no obvious interferences have been found during this period. So this event is possibly related to this shock although all these three stations are more than 1300 km away from the Wenchuan earthquake epicenter.
Buddy-Motivational Interviewing (buddy-MI) to Increase Physical Activity in Community Settings: Study Protocol for a Pragmatic Randomised Controlled Trial
Authors: Brinson David , Wallace-Bell Mark , Kirk Ray , Hornblow Andrew
Published: February 2013

This article describes the development and evaluation of a novel buddy-motivational interviewing intervention intended to help apparently healthy but relatively sedentary adults to adopt and maintain regular physical activity for health and fitness. Many people experience great difficulty in initiating physical activity (“the getting going problem”) and behavioural regression is common (“the keeping it going problem”). Typically there is a rather large gap between what people know to be healthy and what they actually do. This intervention is an adaptation of motivational interviewing in that it adds client-selected motivational-buddies who can provide in-session input as well as ongoing out-of-session support focused on strengthening clients’ motivation for and movement toward their physical activity goals. A pragmatic parallel group randomised controlled trial with 12-month follow-up aims to deliver and assess the effectiveness of the intervention in a format that could realistically be implemented within primary care, workplaces, schools or other similar setting. The study is due to report clinical effectiveness findings in 2014.
Motivational Interviewing for Effective Classroom Management
Authors: Marsh Karen
Published: February 2013

N/A
Motivational Interviewing Step By Step
Authors: Schumacher Julie A.
Published: February 2013

N/A
Fat and Fried: Linking Land Use Law, The Risks of Obesity, and Climate Change
Authors: Tarlock Dan
Published: February 2013

Among the major immediate risks faced by the United States are the increasing rate of obesity of its population and a wide range of potential adverse climate change impacts such as the rising of sea levels, which could result in more extreme flooding and droughts. 2 This article draws from the growing interest in the law and policy of disaster response and risk response3 generated in the wake of Hurricane Katrina. Its focus is the use of law to induce the adaptation of societal behavior to minimize the long-term costs of the two serious risks4 rather than on post-disaster relief. Specifically, this article examines how one set of policy instruments, land use planning and regulation, can help to minimize the costs of these inevitable risks. Obesity and global climate change are here, although their specific impacts are still hard to predict. The basic argument is that spatial planning may help mitigate the two risks and the costs associated with them, even though spatial planning and land use regulation are relatively limited policy instruments to deal with these maddeningly complex social and political problems for two primary reasons. First, the law faces structural barriers; in the main, land use law is designed to produce a “one-off” solution to mitigate a nuisance-like use rather than to produce long-term substantive results. Second, efforts to induce behavioral change challenge the deep-seated value of freedom to live where and how one wants as the quote from the director of disaster relief in Kansas indicates. Nonetheless, the effort is worth making as there are clear links between land use regulation and these two risks.
Determinants which Affect Liquid Asset Ratio of Czech and Slovak Commercial Banks
Authors: Vodová Pavla
Published: February 2013

The aim of this paper is to find out determinants which affect liquid asset ratio of Czech and Slovak commercial banks. The data cover the period from 2001 to 2010. We consider four bank specific factors and nine macroeconomic factors. Results of panel data regression analysis showed that although Czech Republic and Slovak Republic have a lot in common, different factors determined banks´ liquid assets in individual countries. The liquid asset ratio of Czech banks increases with increase of capital adequacy, with depreciation of Czech koruna and with worsening quality of credit portfolio. Liquidity of Slovak banks decreases with size of the bank, with higher capital adequacy, higher bank liquidity and during periods of financial crisis. Liquidity of Slovak banks is also positively related to economic cycle.
« Exit les oreilles » : parodie, ironie et humour féministes dans Nunuche et Nunuche gurlz
Authors: Saint-Martin Lori , Gibeau Ariane
Published: February 2013

Les magazines parodiques Nunuche et Nunuche gurlz méritent l’attention en ce qu’ils présentent un traitement hilarant des procédés rhétoriques dont fait usage la presse féminine tout en posant un regard ironique et incisif sur l’univers de la mode et de la beauté. Cette parodie, étonnamment, n’est pas aussi outrancière qu’elle peut le sembler. En fait, il faut se demander si la presse féminine n’est pas si exagérée dans sa façon de concevoir le féminin qu’elle serait elle-même une parodie, mais une parodie de quoi? Selon Judith Butler, la féminité est une « parodie sans original », une réalité fabriquée qui surgit grâce à plusieurs actions et comportements répétés. La presse féminine serait donc une caricature d’elle-même, la parodie sans original d’un féminin qui n’existe pas, ce que Nunuche permet de mettre en lumière. En recyclant les idées reçues et les clichés parfois indigents de la presse féminine, l’entreprise Nunuche crée du neuf, rend ridicule ce qui cherchait à séduire et produit de l’humour : elle joue ainsi un rôle social et politique indispensable.
La clown : un idéal impossible?
Authors: Cezard Delphine
Published: February 2013

Dans le savoir de sens commun, la figure clownesque est perçue comme étant celle d’un homme. Le poids des habitudes culturelles et sociales engendre une division de pouvoir en faveur des hommes, qui est à même de gêner la présence de femmes au sein de l’art clownesque. En outre, les stéréotypes instaurés concernant les femmes sont de même envergure et de même intensité que ceux qui sont maintenus au sujet du rôle de clown, ce qui complique leur association factuelle. Il s’agit alors de comprendre, à travers évènements historiques et données sociales, comment et pourquoi la femme a tant de mal à être perçue comme pouvant être clown.
La emisión de sestercios del Noroeste a la luz de un nuevo hallazgo
Authors: Cebreiro Ares Francisco
Published: February 2013

.
Bentian. Análisis historiográfico de una ceca vascona
Authors: Torregrosa Yago José Manuel
Published: February 2013

Se realiza una revisión a todos aquellos eruditos y numísmatas que, desde el siglo XVI hasta la actualidad, han ayudado al mejor conocimiento del taller vascón de Bentian. Con este trabajo buscamos poder ayudar a completar el mejor conocimiento de uno de los talleres de escasa producción y la posible localización de este taller vascón (actual provincia de Navarra).
Dispersión del numerario de Sekia
Authors: Stefanelli Francesco Vittorio
Published: February 2013

Se presenta la ordenación y actualización de los hallazgos  de la ceca de Sekia sita en territorio suessetano, por medio de los cuales se deducen las motivaciones históricas de su activación relacionables con la presencia bélica romana  en el Valle del Ebro y su papel integrado en el circuito económico de la zona del río Ebro.
Nova lectura de la inscripció CIL II2/14, 745 d’Onda (Castelló)
Authors: Arasa Gil Ferran , Llorens Joaquín Alfonso , Miguélez González Ana
Published: February 2013

A new interpretation.
Evaluation of B Cell Function in Patients with HIV
Authors: Buckner Clarisa M. , Kardava Lela , Moir Susan
Published: February 2013

HIV disease is associated with abnormalities in all major lymphocyte populations, including B cells. B cell dysfunction in HIV infection is largely driven by alterations in the subsets of B cells that circulate in the blood or reside in tissues. Meaningful functional assays are thus dependent on the identification and isolation of B cell subsets present in the starting material. This unit describes several assays designed to phenotype, fractionate, and assess functional properties of B cells that circulate in the blood of HIV‐infected individuals. The four protocols, which have been adapted from standard techniques, are tailored to evaluate B cells in peripheral blood mononuclear cells (PBMCs) of individuals infected with HIV, but can also be applied to other disease settings and PBMCs isolated from healthy individuals. Curr. Protoc. Immunol. 100:12.13.1‐12.13.18. © 2013 by John Wiley & Sons, Inc.
Experimental Autoimmune Myasthenia Gravis in the Mouse
Authors: Wu Bo , Goluszko Elzbieta , Huda Ruksana , Tüzün Erdem , Christadoss Premkumar
Published: February 2013

Myasthenia gravis (MG) is a T cell–dependent antibody‐mediated autoimmune neuromuscular disease. Antibodies to the nicotinic acetylcholine receptor (AChR) destroy the AChR, thus leading to defective neuromuscular transmission of electrical impulse and to muscle weakness. This unit is a practical guide to the induction and evaluation of experimental autoimmune myasthenia gravis (EAMG) in the mouse, the animal model for MG. Protocols are provided for the extraction and purification of AChR from the electric organs of Torpedo californica, or the electric ray. The purified receptor is used as an immunogen to induce autoimmunity to AChR, thus causing EAMG. The defect in neuromuscular transmission can also be measured quantitatively by electromyography. In addition, EAMG is frequently characterized by the presence of serum antibodies to AChR, which are measured by radioimmunoassay and by a marked antibody‐mediated reduction in the number of muscle AChRs. AChR extracted from mouse muscle is used in measuring serum antibody levels and for quantifying muscle AChR content. Another hallmark of the disease is complement and IgG deposits located at the neuromuscular junction, which can be visualized by immunofluorescence techniques. Curr. Protoc. Immunol. 100:15.8.1‐15.8.26. © 2013 by John Wiley & Sons, Inc.
Measurement of MHC/Peptide Interactions by Gel Filtration or Monoclonal Antibody Capture
Authors: Sidney John , Southwood Scott , Moore Carrie , Oseroff Carla , Pinilla Clemencia , Grey Howard M. , Sette Alessandro
Published: February 2013

This unit describes a technique for the direct and quantitative measurement of the capacity of peptide ligands to bind Class I and Class II MHC molecules. The binding of a peptide of interest to MHC is assessed based on its ability to inhibit the binding of a radiolabeled probe peptide to purified MHC molecules. This unit includes protocols for the purification of Class I and Class II MHC molecules by affinity chromatography, and for the radiolabeling of peptides using the chloramine T method. An alternate protocol describes alterations in the basic protocol that are necessary when performing direct binding assays, which are required for (1) selecting appropriate high‐affinity, assay‐specific, radiolabeled ligands, and (2) determining the amount of MHC necessary to yield assays with the highest sensitivity. After a predetermined incubation period, dependent upon the allele under examination, the bound and unbound radiolabeled species are separated, and their relative amounts are determined. Three methods for separation are described, two utilizing size‐exclusion gel‐filtration chromatography and a third using monoclonal antibody capture of MHC. Data analysis for each method is also explained. Curr. Protoc. Immunol. 100:18.3.1‐18.3.36. © 2013 by John Wiley & Sons, Inc.
Rheological and Drying Considerations for Uniformly Gravure‐Printed Layers: Towards Large‐Area Flexible Organic Light‐Emitting Diodes
Authors: Hernandez‐Sosa Gerardo , Bornemann Nils , Ringle Ingo , Agari Michaela , Dörsam Edgar , Mechau Norman , Lemmer Uli
Published: February 2013

Printing organic semiconductor inks by means of roll‐to‐roll compatible techniques will allow a continuous, high‐volume fabrication of large‐area flexible optoelectronic devices. The gravure printing technique is set to become a widespread process for the high throughput fabrication of functional layers. The gravure printing process of a poly‐phenylvinylene derivative light‐emitting polymer dissolved in a two solvent mixture on poly(3,4‐ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) is studied. The surface tensions, contact angles, viscosities, and drying times of the formulations are investigated as a function of the solvent volume fraction and polymer concentration. The properties of the ink grant a homogeneous printed layer, suitable for device fabrication, when the calculated film leveling time is shorter than a critical time, at which the film has been frozen due to loss of solvent via evaporation. The knowledge obtained from the printing process is applied to fabricate organic light‐emitting diodes (OLEDs) on flexible substrates, yielding a luminance of ≈5000 cd m−2.
Controllable Particle Adhesion with a Magnetically Actuated Synthetic Gecko Adhesive
Authors: Gillies Andrew G. , Kwak Jonghun , Fearing Ronald S.
Published: February 2013

Particle capture and release using controllable adhesion is of growing interest in many fields including reusable adhesives, solar panel cleaning, micro‐manipulation and robot locomotion where current methods of particle management are not sufficient. Here controllable adhesion to glass spheres with a new magnetically actuated synthetic gecko adhesive made from a magnetoelastomer composite is demonstrated. Adhesion is controlled by changing the effective elastic modulus of the surface through actuation of micro surface features with an external magnetic field. A compliant mechanics and magnetic torque analysis explains this general principle and generalizes the results for various geometries. Results show sphere pull‐off forces can be increased 10‐fold by changing the ridge orientation via the external magnetic field, and that the effective elastic modulus can be changed from 65 kPa to 1.5 MPa. Particle transport and release of 500‐ and 1000‐micrometer glass spheres is also demonstrated.
Rigidity‐Patterned Polyelectrolyte Films to Control Myoblast Cell Adhesion and Spatial Organization
Authors: Monge Claire , Saha Naresh , Boudou Thomas , Pózos‐Vásquez Cuauhtemoc , Dulong Virginie , Glinel Karine , Picart Catherine
Published: February 2013

In vivo, cells are sensitive to the stiffness of their microenvironment and to the spatial organization of the stiffness. In vitro studies of this phenomenon can help to better understand the mechanisms of the cell response to spatial variations of the matrix stiffness. Here, polelyelectrolyte multilayer films made of poly(L‐lysine) and a photoreactive hyaluronan derivative are designed. These films can be photo‐crosslinked through a photomask to create spatial patterns of rigidity. Quartz substrates incorporating a chromium mask are prepared to expose selectively the film to UV light (in a physiological buffer), without any direct contact between the photomask and the soft film. It is shown that these micropatterns are chemically homogeneous and flat, without any preferential adsorption of adhesive proteins. Three groups of pattern geometries differing by their shape (circles or lines), size (from 2 to 100 μm), or interspacing distance between the motifs are used to study the adhesion and spatial organization of myoblast cells. The results pave the way for the study of the different steps of myoblast fusion in response to matrix rigidity in well‐defined geometrical conditions.
Rapid, One‐Step, Digital Selective Growth of ZnO Nanowires on 3D Structures Using Laser Induced Hydrothermal Growth
Authors: Yeo Junyeob , Hong Sukjoon , Wanit Manorotkul , Kang Hyun Wook , Lee Daeho , Grigoropoulos Costas P. , Sung Hyung Jin , Ko Seung Hwan
Published: February 2013

For functional nanowire based electronics fabrication, conventionally, combination of complex multiple steps, such as (1) chemical vapor deposition (CVD) growth of nanowire, (2) harvesting of nanowire, (3) manipulation and placement of individual nanowires, and (4) integration of nanowire to circuit are necessary. Each step is very time consuming, expensive, and environmentally unfriendly, and only a very low yield is achieved through the multiple steps. As an alternative to conventional complex multistep approach, original findings are presented on the first demonstration of rapid, one step, digital selective growth of nanowires directly on 3D micro/nanostructures by developing a novel approach; laser induced hydrothermal growth (LIHG) without any complex integration of series of multiple process steps such as using any conventional photolithography process or CVD. The LIHG process can grow nanowires by scanning a focused laser beam as a local heat source in a fully digital manner to grow nanowires on arbitrary patterns and even on the non‐flat, 3D micro/nano structures in a safer liquid environment, as opposed to a gas environment. The LIHG process can greatly reduce the processing lead time and simplify the nanowire‐based nanofabrication process by removing multiple steps for growth, harvest, manipulation/placement, and integration of the nanowires. LIHG process can grow nanowire directly on 3D micro/nano structures, which will be extremely challenging even for the conventional nanowire integration processes. LIHG does not need a vacuum environment to grow nanowires but can be performed in a solution environment which is safer and cheaper. LIHG can also be used for flexible substrates such as temperature‐sensitive polymers due to the low processing temperature. Most of all, the LIHG process is a digital process that does not require conventional vacuum deposition or a photolithography mask.
Precision and accuracy of acetabular size measures in fragmentary hominin pelves obtained using sphere‐fitting techniques
Authors: Hammond Ashley S. , Plavcan J. Michael , Ward Carol V.
Published: February 2013

Hip joint diameter is highly correlated with body size in primates and so can potentially provide important information about the biology of fossil hominins. However, quantifying hip joint size has been difficult or impossible for many important but fragmentary specimens. New three‐dimensional technologies can be used to digitally fit spheres to the acetabular lunate surface, potentially allowing hip joint diameter estimates for incomplete joint surfaces. Here we evaluate the reliability of sphere‐fitting to incomplete lunate surfaces in silico using three‐dimensional polygonal models of extant anthropoid hipbones. Measurement error in lunate sphere‐fitting was assessed at the individual observer level, as well as between observers. Prediction error was also established for acetabular sphere size estimates for smaller divisions of the lunate surface. Sphere‐fitting techniques were then applied to undistorted regions of lunate surface in Plio‐Pleistocene hominin pelves, with a range of diameters constructed from extant error estimates. The results of this study indicate that digital sphere‐fitting techniques are precise and that the lunate does not need to be completely preserved to accurately infer hip dimensions, although some aspects of joint size and morphology can influence sphere size estimates. Joint diameter is strongly predicted by spheres fit to the cranial and caudal halves of the lunate in all anthropoids. We present new hip joint size estimates for a number of fossil hominins, and outline additional applications for digital sphere‐fitting as a morphometric technique. Am J Phys Anthropol 150:565–578, 2013. © 2013 Wiley Periodicals, Inc.
Catalytic transformation of silicon tetraisocyanate Si(NCO)4 to a polymeric silylcarbodiimide
Authors: Schmidt Carsten Ludwig , Jansen Martin
Published: February 2013

A new way for the preparation of inorganic polymeric carbodiimide‐based networks is presented which resembles the transformation of molecular isocyanates using 1‐phenyl‐3‐methyl‐2‐phospholene‐1‐oxide as a catalyst. The respective reaction sequence, well established in preparative organic chemistry, has been applied for the synthesis of carbodiimide‐based SiNC(O) materials. Starting from Si(NCO)4 (silicon tetraisocyanate), a transformation to an insoluble extended inorganic array was achieved in boiling dodecan (T = 216 °C). Analysis of the polymer using X‐ray diffraction, FT‐IR, density measurement, matrix‐assisted laser desorption/ionization time of flight and TGA revealed that this highly moisture‐sensitive amorphous network consists of oligomers of high molar mass and exhibits a high density of around 1.5 g cm−3, which corresponds quite well to the calculated density of crystalline Si(NCN)2 reported in the literature. Degradation of this 'SiNC(O) phase' with the release of N2 and (CN)2 finally provided SiC as the only crystalline product. No indication of the formation of crystalline Si3N4 or intermediate crystalline 'SiC2N4', silicon carbodiimide (= Si(NCN)2), was noticed. Copyright © 2013 John Wiley & Sons, Ltd.
Modulation of the F1FO‐ATPase function by butyltin compounds
Authors: Nesci Salvatore , Ventrella Vittoria , Pagliarani Alessandra
Published: February 2013

Among butyltin compounds, tributyltin (TBT), widely exploited in the past in antifouling paints for its biocidal properties, is long known as one of the most harmful sea contaminants. Among the ascertained and universal toxicity mechanisms, TBT targeting F1FO‐ATPase and thus impairing cell bioenergetics, is here reviewed. While TBT effects on F1FO‐ATPase have been investigated for decades, the possible impact of the derivatives dibutyltin (DBT) and monobutyltin (MBT), produced by abiotic and/or biotic dealkylation of TBT and usually considered far less toxic, have been poorly explored up until now. Butyltin effects on F1FO‐ATPase and their underlying action mechanism seem to be tightly structure dependent. Butyltins are membrane‐active toxicants. Owing to its more pronounced lipophilicity TBT targets the transmembrane FO sector, blocks ionic translocation and causes a dose‐dependent loss of sensitivity to FO inhibitors such as oligomycin and N,N′‐dicyclohexylcarbodiimide. DBT strongly inhibits F1FO‐ATPase activity by competing with the Mg+2 cofactor in the F1 catalytic site but is ineffective on the enzyme sensitivity to FO inhibitors. MBT is apparently ineffective. The possible contribution of DBT to the overall butyltin toxicity on membrane systems may not be neglectable since usually TBT coexists with its derivatives in organotin‐exposed animal tissues. Copyright © 2013 John Wiley & Sons, Ltd.
Synthesis and Biological Evaluation of Some Pyrazoline Derivatives Bearing a Dithiocarbamate Moiety as New Cholinesterase Inhibitors
Authors: Altintop Mehlika D. , Özdemir Ahmet , Kaplancikli Zafer A. , Turan‐Zitouni Gülhan , Temel Halide E. , Çiftçi Gülşen A.
Published: February 2013

In the present study, new pyrazoline derivatives were synthesized via the reaction of 1‐(chloroacetyl)‐3‐(2‐furyl)‐5‐aryl‐2‐pyrazolines with sodium salts of N,N‐disubstituted dithiocarbamic acids. Each derivative was evaluated for its ability to inhibit acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) using a modification of Ellman's spectrophotometric method. The compounds were also investigated for their cytotoxic properties using the MTT assay. The most potent AChE inhibitor was found as compound 7 followed by compounds 27 and 17, when compared with eserine. Compounds effective on AChE carry the 2‐dimethylaminoethyl moiety, which resembles the trimethylammonium group and the ethylene bridge of acetylcholine. Among all compounds, compound 7 bearing 2‐dimethylaminoethyl and 3,4‐methylenedioxyphenyl moieties was also found to be the most effective inhibitor of BuChE. The MTT assay indicated that the effective concentration of compound 7 was lower than its cytotoxic concentration.
Computed tomography‐enhanced anatomy course using enterprise visualization
Authors: May Hila , Cohen Haim , Medlej Bahaa , Kornreich Liora , Peled Nathan , Hershkovitz Israel
Published: February 2013

Rapid changes in medical knowledge are forcing continuous adaptation of the basic science courses in medical schools. This article discusses a three‐year experience developing a new Computed Tomography (CT)‐based anatomy curriculum at the Sackler School of Medicine, Tel Aviv University, including describing the motivations and reasoning for the new curriculum, the CT‐based learning system itself, practical examples of visual dissections, and student assessments of the new curriculum. At the heart of this new curriculum is the emphasis on studying anatomy by navigating inside the bodies of various living individuals utilizing a CT viewer. To assess the students’ experience with the new CT‐based learning method, an anonymous questionnaire was administered at the end of the course for three consecutive academic years: 2008/2009, 2009/2010, 2010/2011. Based upon the results, modifications were made to the curriculum in the summers of 2009 and 2010. Results showed that: (1) during these three years the number of students extensively using the CT system quadrupled (from 11% to 46%); (2) students' satisfaction from radiologists involvement increased by 150%; and (3) student appreciation of the CT‐based learning method significantly increased (from 13% to 68%). It was concluded that discouraging results (mainly negative feedback from students) during the first years and a priori opposition from the teaching staff should not weaken efforts to develop new teaching methods in the field of anatomy. Incorporating a new curriculum requires time and patience. Student and staff satisfaction, along with utilization of the new system, will increase with the improvement of impeding factors. Anat Sci Educ 6: 332–341. © 2013 American Association of Anatomists.
Formation of Nanostructured MnO/Co/Solid–Electrolyte Interphase Ternary Composites as a Durable Anode Material for Lithium‐Ion Batteries
Authors: Dang Feng , Oaki Yuya , Kokubu Takao , Hosono Eiji , Zhou Haoshen , Imai Hiroaki
Published: February 2013

Nanoporous MnO frameworks with highly dispersed Co nanoparticles were produced from MnCO3 precursors prepared in a gel matrix. The MnO frameworks that contain 20 mol % Co exhibited excellent cycle performance as an anode material for Li‐ion batteries. The solid–electrolyte interphase (SEI) formed in the frameworks through the electrochemical reaction mediates the active materials, such as MnO, Mn, and Li2O, during the conversion reaction in the charge–discharge cycle. The Co nanoparticles and SEI provide the electron and Li‐ion conductive networks, respectively. The ternary nanocomposites of the MnO framework, metallic Co nanoparticles, and embedded SEI are categorized as durable anode materials for Li‐ion batteries.