bluuebunny/crossref_metadata_2025 huggingface dataset:
SOFT COMPUTING APPROACH FOR LIQUEFACTION IDENTIFICATION USING LANDSAT-7 TEMPORAL INDICES DATA
Authors: Sengar S. S. , Kumar A. , Ghosh S. K. , Wason H. R.
Published: August 2012

Abstract. A strong earthquake with magnitude Mw7.7 that shook the Indian Province of Gujarat on the morning of January 26, 2001, caused widespread appearance of water bodies and channels, in the Rann of Kachchh and the coastal areas of Kandla port. In this work, the impact of using conventional band ratio indices from Landsat-7 temporal images for liquefaction extraction was empirically investigated and compared with Class Based Sensor Independent (CBSI) spectral band ratio while applying noise classifier as soft computing approach via supervised classification. Five spectral indices namely, SR (Simple Ratio), NDVI (Normalized Difference Vegetation index), TNDVI (Transformed Normalized Difference Vegetation Index), SAVI (Soil-Adjusted Vegetation Index) and Modified Normalized Difference Water Index (MNDWI) were investigated to identify liquefaction using temporal multi-spectral images. It is found that CBSI-TNDVI with temporal data has higher membership range (0.968–0.996) and minimum entropy (0.011) to outperform for extraction of liquefaction and for water bodies extraction membership range (0.960–0.996) and entropy (0.005) respectively.
REMOTE SENSING IN A CHANGING CLIMATE AND ENVIRONMENT: THE RIFT VALLEY FEVER CASE
Authors: Tourre Y. M. , Lacaux J.-P. , Vignolles C. , Lafaye M.
Published: August 2012

Abstract. Climate and environment are changing rapidly whilst global population already reached 7 billions people. New public health challenges are posed by new and re-emerging diseases. Innovation is a must i.e., 1) using high resolution remote sensing, 2) re-invent health politics and trans-disciplinary management. The above are part of the 'TransCube Approach' i.e., Transition, Translation, and Transformation. The new concept of Tele-epidemiology includes such approach. A conceptual approach (CA) associated with Rift Valley Fever (RVF) epidemics in Senegal is presented. Ponds are detected using high-resolution SPOT-5 satellite images and radar data from space. Data on rainfall events obtained from the Tropical Rainfall Measuring Mission (NASA/JAXA) are combined with in-situ data. Localization of vulnerable and parked hosts (obtained from QuickBird satellite) is also used. The dynamic spatio-temporal distribution and aggressiveness of RVF mosquitoes, are based on total rainfall amounts, ponds' dynamics and entomological observations. Detailed risks maps (hazards + vulnerability) in real-time are expressed in percentages of parks where animals are potentially at risks. This CA which simply relies upon rainfall distribution from space, is meant to contribute to the implementation of the RVF early warning system (RVFews). It is meant to be applied to other diseases and elsewhere. This is particularly true in new places where new vectors have been rapidly adapting (such as Aedes albopictus) whilst viruses (such as West Nile and Chikungunya,) circulate from constantly moving reservoirs and increasing population.
The Essence of ATP Coupling
Authors: Bazhin Nikolai
Published: August 2012

The traditional explanation of ATP coupling is based on the raising of the equilibrium constants of the biochemical reactions. But in the frames of the detailed balance, no coupling occurs under thermodynamic equilibrium. The role of ATP in coupling is not that it provides an increase in the equilibrium constants of thermodynamically unfavorable reactions but that the unfavorable reactions are replaced by other reactions which kinetically are more favorable and give rise to the same products. The coupling with ATP hydrolysis results in the formation of quasistationary intermediate states.
Resistance of Gram-Negative Bacilli in Lebanon
Authors: Salem S. E. , Dahdouh E. , Daoud Z.
Published: August 2012

Several studies have reported the isolation of resistant Gram-Negative Bacilli in Lebanon. However, those studies are new and scarce as compared to worldwide data and mostly restricted to single center studies. In this review, we attempt to provide a reliable and comprehensive report describing the current situation and providing prospects for bacterial resistance in Lebanon. Several studies have shown that Extended Spectrum β-Lactamase-producing E. coli and K. pneumoniae strains are being increasingly reported. Moreover, 2.15% of E. coli and 7.84% of K. pneumoniae isolates have shown carbapenem resistance and up to 30% of isolated E. coli strains were found to be Multi-Drug Resistant. Molecular studies showed that the most widespread β-Lactamases in Lebanon are of the CTX-M-15 and SHV types. In addition, K. pneumoniae strains producing metallo-β-Lactamase and Klebsiella pneumoniae Carbapenemase have been reported. Resistant Pseudomonas aeruginosa and Acinetobacter baumannii caused several nosocomial infections and some Acinetobacter baumannii strains were found to produce OXA-58 type ESBL. The few data addressing the rate of antibiotic consumption in Lebanon show a high rate of antibiotic misuse and abuse. In conclusion, there is a need for antibiotic stewardship programs and additional studies that go beyond the scope of single-center studies in Lebanon.
Progreso en el programa nacional español de mejora de cebada
Authors: Gracia M. P. , Mansour E. , Casas A. M. , Lasa J. M. , Medina B. , Molina-Cano J. L. , Moralejo M. A. , López A. , López-Fuster P. , Escribano J. , Ciudad F. J. , Codesal P. , Montoya J. L. , Igartua E.
Published: August 2012

El programa nacional de mejora de cebada se lleva a cabo por cuatro organismos públicos situados en las principales regiones productoras de cebada de España. El objetivo de este estudio es la evaluación retrospectiva de i) el progreso en términos de rendimiento y ii) la magnitud y el efecto de la interacción genotipo-por ambiente del rendimiento en los materiales avanzados. La base de datos utilizada consiste en datos de rendimiento absoluto y relativo y fechas de floración de 349 líneas F8, F9 y F10, además de testigos, evaluadas en 163 ensayos distribuidos en 11 años. Las localidades de ensayo están en las provincias de Albacete, Lleida, Valladolid y Zaragoza. El progreso del programa se estimó utilizando el rendimiento relativo analizado mediante modelos mixtos para homogeneizar los resultados entre años y localidades, que son muy desequilibrados. Se constató la existencia de progreso en el programa, aumentando los rendimientos en cada generación, hasta superar a los testigos, aunque el progreso varió entre provincias y entre localidades. La ganancia genética fue mayor de F8 a F9 que de F9 a F10. El componente de varianza más grande (además de los puramente ambientales) fue el de genotipo por localidad y por año, por lo que los patrones geográficos eran imprevisibles. La relación entre fecha de floración y rendimiento en general fue débil en todas las localidades en esta etapa avanzada del programa. El programa puede continuar con la misma estructura, pero se debería investigar la causa del menor progreso obtenido en algunas localidades.
La eficiencia productiva de la agricultura ecológica: el caso del sector de la uva en Cataluña
Authors: Guesmi B. , Serra T. , Kallas Z. , Gil Roig J. M.
Published: August 2012

Conocer las diferencias de productividad y eficiencia entre la agricultura convencional y la ecológica tiene implicaciones importantes para la evaluación de la viabilidad económica de estas dos prácticas agrícolas. El principal objetivo de este estudio fue comparar la eficiencia técnica de las explotaciones de uva ecológicas y convencionales en Cataluña. Para ello utilizamos el modelo de la frontera de producción estocástica. El análisis se basó en datos de corte transversal de una muestra de 141 explotaciones catalanas especializadas en la producción de uva. Los agricultores ecológicos fueron, de promedio, técnicamente más eficientes que los convencionales (los ratios de eficiencia fueron 0,80 y 0,64, respectivamente). Además de la adopción de técnicas ecológicas, la experiencia también incrementa la eficiencia técnica. En cambio, las explotaciones con una mayor proporción de trabajo no remunerado, que se encuentran en una zona desfavorecida y/o que tienden a tener fuertes preferencias por preservar el medio ambiente, son generalmente menos eficientes.
Analyzing farming systems diversity: a case study in south-western France
Authors: Choisis J. P. , Thévenet C. , Gibon A.
Published: August 2012

The huge changes in agricultural activities, which may be amplified by the forthcoming Common Agriculture Policy reform, call the future of crop-livestock systems into question and hence the impact of these changes on landscapes and biodiversity. We analyzed relationships between agriculture, landscape and biodiversity in south-western France. The study area covered about 4000 ha and included four villages. We conducted a survey of 56 farms. Multivariate analysis (multiple factor analysis and cluster analysis) were used to analyze relationships between 25 variables and to build a typology. The type of farming (beef and/or dairy cattle, cash crops), size (area and workforce) and cultivation practices, among others, were revealed as differentiating factors of farms. Six farming types were identified (1) hillside mixed crop-livestock farms, (2) large ‘corporate’ farms, (3) extensive cattle farms, (4) large intensive farms on the valley sides, (5) small multiple-job holdings, and (6) ‘hobby’ farms. The diversity of farming systems revealed the variable impact of the main drivers of change affecting agricultural development, particularly the enlargement and modernization of farms along with the demography of agricultural holdings.
Evaluation of “ground sensing” optical sensors for diagnosis of Plasmopara viticola on vines
Authors: Calcante A. , Mena A. , Mazzetto F.
Published: August 2012

The present work considers the possible use of two commercial optical devices, the GreenSeeker RT100 and the Crop Circle, in detecting different levels of grapevine downy mildew symptoms. The analysis was conducted on vine leaves that had been picked from plants of cv. Cabernet Franc infected by Plasmopara viticola. Leaves were divided into eight homogeneous infection classes and then analyzed (on the leaves’ adaxial surfaces) through the optical devices and a portable visible/near infrared (Vis/NIR) spectrophotometer used as tester. Data showed a linear relation between the percentage of symptomatic leaf area and the Normalized Difference Vegetation Index (NDVI) calculated through the optical sensors (R2 = 0.708 for GreenSeeker; R2 = 0.599 for Crop Circle; R2 = 0.950 for the spectrophotometer). The regression obtained for GreenSeeker is more significant than the one obtained for Crop Circle. This fact suggests a greater capability of GreenSeeker than Crop Circle in detecting different disease levels and its possible use in diagnosis application in the vineyard. Finally, the NDVI measurements carried out through the two commercial sensors, showed lower values on abaxial surfaces than on adaxial surfaces, and a reduced range of values. Moreover, the identification of different infection classes was more difficult on the abaxial surface. This is due to both the different structure of the leaf tissue and the different symptoms of P. viticola on the abaxial and adaxial surfaces. The present work will allow, in the future, applying these optical devices to diagnosis directly in vineyards.
Preliminary survey of leading general medicine journals’ use of Facebook and Twitter
Authors: Kamel Boulos Maged N. , Anderson Patricia F.
Published: August 2012

Aim: This study is the first to chart the use of Facebook and Twitter by peer-reviewed medical journals. Methods: We selected the top 25 general medicine journals on the Thomson Reuters Journal Citation Report (JCR) list. We surveyed their Facebook and Twitter presences and scanned their Web sites for any Facebook and (or) Twitter features as of November 2011. Results/Discussion: 20 of 25 journals had some sort of Facebook presence, with 11 also having a Twitter presence. Total ‘Likes’ across all of the Facebook pages for journals with a Facebook presence were 321,997, of which 259, 902 came from the New England Journal of Medicine (NEJM) alone. The total numbers of Twitter ‘Followers’ were smaller by comparison when compiled across all surveyed journals. ‘Likes’ and ‘Followers’ are not the equivalents of total accesses but provide some proxy measure for impact and popularity. Those journals in our sample making best use of the open sharing nature of social media are closed-access; with the leading open access journals on the list lagging behind by comparison. We offer a partial interpretation for this and discuss other findings of our survey, provide some recommendations to journals wanting to use social media, and finally present some future research directions. Conclusions: Journals should not underestimate the potential of social media as a powerful means of reaching out to their readership.
Major Incident Experience and Preparedness in a Developing Country
Authors: Seyedin Hesam , Zaboli Rouhollah , Ravaghi Hamid
Published: August 2012

Background

Research shows that having previous experience of major incidents has a positive impact on awareness and preparedness of organizations. We investigated the effects of major incident experience on preparedness of health organizations on future disasters in Iran.

Methods

A qualitative study using a semistructured interview technique was conducted with 65 public health and therapeutic affairs managers. Analysis of the data was performed used the framework analysis technique, which was supported by qualitative research software.

Results

The study found that prior experience of major incidents results in better performance, coordination, and cooperation in response to future events. There was a positive effect on policy making and resource distribution and an increase in (1) preparedness activities, (2) raising population awareness, and (3) improving knowledge. However, the preparedness actions were predominantly individual-dependent.

Conclusions

Our findings showed that to increase system efficiency and effectiveness within health organizations, an appropriate major incident management system is needed. The new system can use lessons learned from previous major incidents to better equip health organizations to cope with similar events in the future. (Disaster Med Public Health Preparedness. 2013;7:313-318)
Enrichment and Detection of Tyrosine‐Nitrated Proteins
Authors: Dekker Frank , Abello Nicolas , Wisastra Rosalina , Bischoff Rainer
Published: August 2012

Nitrotyrosine is a post‐translationally modified amino acid with distinctly different properties than tyrosine or any other of the genetically encoded amino acids. Detecting proteins containing nitrotyrosine is the first step towards a better understanding of the role of nitrotyrosine in health and disease. Moreover, quantifying the extent of nitrotyrosine and determining its location in a protein forms the basis for a better understanding of the effect of tyrosine nitration on biological function. Described in this unit is a method to detect tyrosine‐nitrated proteins in tissue sections and on western blots after creating a fluorescent complex between aminotyrosine, salicylaldehyde, and Al3+. In addition, an approach is detailed for labeling aminotyrosine with biotin to enrich peptides from complex samples. Both methods require reduction of nitrotyrosine to aminotyrosine, which can be achieved with sodium dithionite or hemin plus dithiothreitol. Curr. Protoc. Protein Sci. 69:14.13.1‐14.13.19. © 2012 by John Wiley & Sons, Inc.
Generation and Characterization of Mouse Basophils from Bone Marrow and Purification of Basophils from Spleen
Authors: Yoshimoto Tomohiro , Nakanishi Kenji
Published: August 2012

Basophils are rare circulating granulocytes that originate from progenitor cells in the bone marrow and have been considered important effector cells in IgE‐mediated allergic inflammation. Basophils constitute <1% of blood leukocytes and are usually absent or present only in small numbers in tissues. They may, however, be recruited to inflammatory sites when an antigen is present and contribute immediately to hypersensitivity reactions. Basophils can therefore serve as primary effector cells in allergic disorders. Despite a large pool of experimental evidence that has led to the discovery of these functional attributes of basophils, many questions regarding their contribution to these immune responses remain unanswered. This is due, in part, to the lack of methods for generation and purification of basophils and the lack of animal models appropriate for their functional analysis. Recent studies, however, have revealed a role for basophils as antigen‐presenting cells that preferentially induce Th2 cells in response to complexes of antigen plus antigen‐specific IgE, to protease allergens, or to helminth parasites in vitro and in vivo through the production of “early IL‐4” and the presentation to CD4+ T cells of complexes of peptide plus MHC class II molecules. These findings have uncovered previously unknown functional characteristics of basophils. Knowledge of these and other functional properties of basophils may translate into the design of novel therapeutic strategies for Th2‐IgE‐mediated diseases, such as bronchial asthma. In this unit, protocols that will enable the study of mouse basophils are described. Curr. Protoc. Immunol. 98:3.24.1‐3.24.16. © 2012 by John Wiley & Sons, Inc.
Isolation of Human Eosinophils
Authors: Akuthota Praveen , Shamri Revital , Weller Peter F.
Published: August 2012

Highly purified eosinophils can be isolated from peripheral blood by negative selection using an antibody‐based magnetic negative selection protocol. The basic protocol describes a sequential fractionation of peripheral blood in which CD16+ granulocytes are enriched first from whole blood, followed by isolation of eosinophils. This technique is easy to use, fast, and highly reproducible. Support protocols describe a staining methods that can be used to evaluate the purity of eosinophils and differentiation from other leukocyte populations. Curr. Protoc. Immunol. 98:7.31.1‐7.31.8. © 2012 by John Wiley & Sons, Inc.
A Metal‐Free Sulfenylation and Bromosulfenylation of Indoles: Controllable Synthesis of 3‐Arylthioindoles and 2‐Bromo‐3‐arylthioindoles
Authors: Huang Dayun , Chen Jiuxi , Dan Weixing , Ding Jinchang , Liu Miaochang , Wu Huayue
Published: August 2012

An efficient metal‐free sulfenylation of indoles with disulfides has been developed, leading to 3‐arylthioindoles in moderate to excellent yields. Furthermore, bromosulfenylation of indoles with disulfides has been realized for the first time providing a new family of 2‐bromo‐3‐arylthioindole derivatives in good yield by the one‐pot construction of CS and CBr bonds. It is noteworthy that the system enables the use of both the RS moieties in RSSR and shows a broad functional group tolerance.
Photochemical Methods for the Conversion of Light into Chemical Energy
Authors: Grätzel Michael
Published: August 2012

This paper is concerned with reaction systems in which fuel production is achieved by illumination of aqueous solutions. Research interest in this field focusses on photoredox reactions magnified image in which R and S are solutes of which one is excited by light. Major problems to overcome for practical use of these systems are the retardation of the back reaction and the back conversion of R− and S+ under production of a fuel. To accomplish the production of the back reaction microscopically, heterogeneous solutions containing molecular assemblies such as micelles or vesicles have been employed. Here, through judicious choice of the molecular system, in particular the use of functional electron relays, charge separation can be achieved. This concept has been coupled with the use of colloidal redox catalysts to bring about hydrogen and oxygen formation from water magnified imageSystems which produce hydrogen and/or oxygen from water through illumination with visible light will be reviewed and most recent experimental results from our and other laboratories discussed.
Physico‐Chemical Problems in Photovoltaic Research
Authors: Wagner Sigurd
Published: August 2012

Today's single crystal silicon solar cell is a mature product. It is based on processes of photoexcitation, and of charge separation in space whose physics are well understood. However, the economical application of photovoltaic modules on a large scale is contingent upon substantial cost reduction. Conventional semiconductor fabrication technology needs to be supplanted by processes characteristic of industrial chemistry. This transition depends on the solution of a number of physico‐chemical problems which range from solid‐state chemistry to chemical engineering. In this brief review we discuss the principles of solar cell operation, key manufacturing steps, and four areas of research: the preparation and purification of silicon, the growth of ribbon crystals, deep‐level impurities, and the effect of grain boundary impurities.
Verbesserte oder neue Möglichkeiten zur Kraft‐Wärme‐Umwandlung durch Anwendung neuer Stoffe
Authors: Alefeld G.
Published: August 2012

Gewisse reversible Reaktionen, bei denen durch Wärmezufuhr aus einer flüssigen oder festen Phase eine gasförmige Komponente entweicht bzw. bei Absorption einer gasförmigen Komponente Wärme entsteht, werden zukünftig vermehrt zur Wärmespeicherung, zur Transformation von Wärme zwischen verschiedenen Temperaturniveaus sowie zur Erzeugung von Arbeit aus Wärme oder Wärme aus Arbeit genutzt werden. In geeigneten Diagrammen wird gezeigt, daß diese Sorptionskreisprozesse als arbeitsleistende und arbeitszehrende Clausius‐Rankine‐Prozesse mit mehrkomponentigen Arbeitsfluiden verstanden werden können. Mit Hilfe dieser Analyse werden die sogenannten „chemischen Motoren”︁, die verschiedenen Betriebsvarianten der Absorptionswärmepumpe, die Kompressorwärmepumpe mit Lösungskreislauf und Wärmespeicherzyklen diskutiert. — Beispiele für Arbeitsstoffpaare und Möglichkeiten zu deren Verbesserung werden angegeben. Eine neuartige Hochtemperaturabsorberwärmepumpe, die mit der Stoffkombination Zeolith/H2O arbeitet, wird vorgestellt.
Micellar Effects Upon the Reactions of the Setoglaucin Carbocation with Cyanide Ion
Authors: Srivastava S. K. , Katiyar Sarvagya S.
Published: August 2012

The reaction of setoglaucin with cyanide ion exhibits 357 fold catalysis in presence of cationic micelles of cetyltrimethylammonium bromide and 23 fold inhibition in presence of anionic micelles of sodium dodecyl sulfate. The effect of concentrations of detergent, substrate and reactant has been investigated. The data on the effect of counterions have been analysed by the model scheme and mathematical formulations developed by Patel and Katiyar [5, 6]. The anionic counterions have an inhibitory effect on the CTAB catalysed reaction of setoglaucin in the following order: N3− > NO3− > Br− > Cl− > F− > NO salt. Similarly the SDS inhibited reaction of setoglaucin shows an increase in the rate on the addition of cations like Cs+, K+, Na+, and Li+. However when the micelle affected reaction was studied in presence of alcohols, the rate of the CTAB catalysed reaction of setoglaucin with CN− was found to decrease with the increase in alcohol concentration. The alcohol with the longer alkyl chain was more effective: n‐butanol > n‐propanol > ethanol > methanol. The effect of the temperature on the reaction rate has also been examined.
The Molar Volume of Partially Associated Electrolytes Exemplified by CdSO4 in H2O  CH3CN‐Mixtures
Authors: Schwitzgebel G. , Lührs C. , Barthel J.
Published: August 2012

Our model for the volume of partially associating electrolytes is based on the limiting law of Redlich and Rosenfeld for the electrolyte fraction of free ions and on the law of ideal mixing for the ion pairs. The resulting analytical density formula contains the partial molar volumes of the ions at infinite dilution VY∞ and of the ion pairs VA. These two parameters can be evaluated by a least squares method, if the association constant is determined independently. This has been done conductometrically for the test system CdSO4 in H2O‐acetonitrile (AN)‐mixtures. A magnetic suspension balance, reaching a sensitivity of σd = 2 · 10−6 g cm−3, proved to be well suited for the density measurements. Data at 25°C are presented for solutions with AN‐contents up to 21.3 mole percent and CdSO4‐concentrations between 4 · 10−3 and 4 · 10−2 mol dm−3. — The values of V∞ (CdSO4) are not equal to the intercepts obtained by conventional √ c‐extrapolations. The low values of VY∞ and of VA indicate volume saving solvation arrangements. A reevaluation of published density data of CaSO4 and of MgSO4 yields an almost identical value for the volume change of ion pair formation and agrees well with results calculated from the pressure dependence of the association constant.
Thermodynamische Untersuchungen an Menshutkin‐Komplexen. 1. Bildungsenthalpie und ‐entropie des Komplexes 2SbCl3 · C6H6
Authors: Perkampus H.‐H. , Sondern Chr.
Published: August 2012

An dem binären System SbCl6/C6H6 wurden die Aktivitäten in der flüssigen Mischphase als Funktion von Temperatur und Zusammensetzung durch Dampfdruckmessungen bestimmt. Aus den Abweichungen vom idealen Verhalten läßt sich auf die Existenz gelöster Komplexe schließen. Dies wird bestätigt durch die kalorimetrisch bestimmte exotherme Mischungsenthalpie. Durch zusätzliche Dampfdruck‐messungen über dem festen Komplex gelingt es, die Bildungsenthalpie des festen Komplexes auf insgesamt drei voneinander unabhängige Methoden zu ermitteln. Es ergibt sich ein mittlerer Wert von ΔHKomplex0 = ‐55,4 kJ mol−1 für die Bildung aus den reinen, flüssigen Komponenten.
Influence of Humidity on Polymorphic Transformations. Meprobamate
Authors: Ramberger R. , Burger A. , Schulte K.
Published: August 2012

The extraordinarily strong influence of humidity on the kinetics of the irreversible polymorphic transition from meprobamate mod. III to mod. II is studied. The transformation rate varies between zero (in dry air) and 0.6 h−1 (in 80% relative humidity). A kinetic model is formulated which describes the data determined spectroscopically well. According to this model, the effect is explained by the formation of sorption layers, where dissolution processes strongly enhance the transformation rate and capillary condensation plays an important role. The strong influence of traces of water has its origin in the interaction of the water molecules with the CO group of meprobamate.
Ganzheitliche Eignungsbewertung von Sekundärrohstoffen für den Einsatz in Beton
Authors: Herbst Tristan , Meng Birgit , Rübner Katrin
Published: August 2012

Der Einsatz von Sekundärrohstoffen im Betonbau kann einen wesentlichen Beitrag zu einer nachhaltigen Ressourcenwirtschaft im Bauwesen leisten. Sekundärrohstoffe (Recycling‐Baustoffe, RC‐Baustoffe) finden bereits Anwendung als Roh‐ bzw. Brennstoffe in der Portlandzementklinkerherstellung, als Zementbestandteile, als Betonzusatzstoffe sowie als sekundäre Gesteinskörnungen in Beton. In einem Teilprojekt des DAfStb/BMBF‐Verbundforschungsvorhabens “Nachhaltig Bauen mit Beton” wurde das Einsatzpotenzial von Sekundärrohstoffen in Beton untersucht. Hierbei spielen sowohl technische als auch ökologische und ökonomische Fragestellungen eine wichtige Rolle. Vor diesem Hintergrund wurde eine Bewertungsgrundlage mit ganzheitlicher Betrachtung von Nachhaltigkeitsaspekten (Technik, Ökologie, Ökonomie) ausgearbeitet. Dieses Bewertungskonzept umfasst die vier Bewertungsschritte: I. Grundsätzliche Überlegungen, II. Vorteile für das nachhaltige Bauen, III. Alternative Bewertungswege und IV. Sensitivitätsanalysen. Das Bewertungskonzept wurde am Beispiel der bereits im Betonbau eingesetzten rezyklierten Gesteinskörnungen entwickelt.

Holistic concept to assess the applicability of secondary materials in concrete

Nowadays there are several applications of secondary mineral materials and residues. In the framework of the German research project “Sustainable Building with Concrete”, a concept to assess the applicability of already used and new secondary materials in concrete has been developed. It considers sustainability aspects and includes the following four assessment steps: I. Basic considerations, II. Advantages for sustainable construction, III. Alternative paths of application, and IV. Sensitivity analysis. Depending on changing technical, ecological and economic aspects, the assessment has to be performed for changed technical, ecological and economic conditions as necessity arises.
The BOHR effect before Perutz
Authors: Brunori Maurizio
Published: August 2012

Before the outbreak of World War II, Jeffries Wyman postulated that the Bohr effect in hemoglobin demanded the oxygen linked dissociation of the imidazole of two histidines of the polypeptide. This proposal emerged from a rigorous analysis of the acid–base titration curves of oxy‐ and deoxy‐hemoglobin, at a time when the information on the chemistry and structure of the protein was essentially nil. The magnetochemical properties of hemoglobin led Linus Pauling to hypothesize that the (so called) Bohr histidines were coordinated to the heme iron in the fifth and sixth positions; and Wyman shared this opinion. However, this structural hypothesis was abandoned in 1951 when J. Wyman and D. W. Allen proposed the pK shift of the oxygen linked histidines to be the result of “…a change of configuration of the hemoglobin molecule as a whole accompanying oxygenation.” This shift in paradigm, that was published well before the 3D structure of hemoglobin was solved by M.F. Perutz, paved the way to the concept of allostery. After 1960 the availability of the crystallographic structure opened new horizons to the interpretation of the allosteric properties of hemoglobin.
Cranial roots of the accessory nerve exist in the majority of adult humans
Authors: Tubbs R. Shane , Benninger Brion , Loukas Marios , Cohen-Gadol Aaron A.
Published: August 2012

The inclusion of a cranial root as a component of the accessory nerve is controversial with at least one recent study claiming that intracranial rootlets do not exist in humans. In response to this debate, the present study aimed to clarify this anatomy in a large cadaveric sample. In this study, 43 adult cadavers (86 sides) were dissected via a posterior approach to the craniocervical junction. Observations were made for the presence or absence of cranial roots of the accessory nerve, and when present, their lengths and diameters were measured. Relationships of these rootlets were documented. A cranial root of the accessory nerve was identified in 76% of sides. When identified, 1–6 cranial rootlets (mean 4.5) of the accessory nerve were observed. They ranged in diameter from 0.1 to 1.1 mm (mean 0.7 mm). The length of these nerves ranged from 8 to 24 mm with a mean of 17 mm. In general, the more superior rootlets were shorter and the more inferior rootlets were longer. Although there was a slight tendency for the cranial roots to be more numerous and larger on right sides and in males, this did not reach statistical significance. We believe this to be the largest study to date documenting the presence of a cranial root of the accessory nerve. Based on our findings, a cranial root exists in the majority of specimens. Neurosurgical procedures or high quality imaging of this area should enable the physician to see these structures. Clin. Anat. 27:102–107, 2014. © 2012 Wiley Periodicals, Inc.
Hydroxynitrile Lyases with α/β‐Hydrolase Fold: Two Enzymes with Almost Identical 3D Structures but Opposite Enantioselectivities and Different Reaction Mechanisms
Authors: Andexer Jennifer N. , Staunig Nicole , Eggert Thorsten , Kratky Christoph , Pohl Martina , Gruber Karl
Published: August 2012

Hydroxynitrile lyases (HNLs) catalyze the cleavage of cyanohydrins to yield hydrocyanic acid (HCN) and the respective carbonyl compound and are key enzymes in the process of cyanogenesis in plants. In organic syntheses, HNLs are used as biocatalysts for the formation of enantiopure cyanohydrins. We determined the structure of the recently identified, R‐selective HNL from Arabidopsis thaliana (AtHNL) at a crystallographic resolution of 2.5 Å. The structure exhibits an α/β‐hydrolase fold, very similar to the homologous, but S‐selective, HNL from Hevea brasiliensis (HbHNL). The similarities also extend to the active sites of these enzymes, with a Ser‐His‐Asp catalytic triad present in all three cases. In order to elucidate the mode of substrate binding and to understand the unexpected opposite enantioselectivity of AtHNL, complexes of the enzyme with both (R)‐ and (S)‐mandelonitrile were modeled using molecular docking simulations. Compared to the complex of HbHNL with (S)‐mandelonitrile, the calculations produced an approximate mirror image binding mode of the substrate with the phenyl rings located at very similar positions, but with the cyano groups pointing in opposite directions. A catalytic mechanism for AtHNL is proposed, in which His236 from the catalytic triad acts as a general base and the emerging negative charge on the cyano group is stabilized by main‐chain amide groups and an α‐helix dipole very similar to α/β‐hydrolases. This mechanistic proposal is additionally supported by mutagenesis studies.
Direct Cloning, Genetic Engineering, and Heterologous Expression of the Syringolin Biosynthetic Gene Cluster in E. coli through Red/ET Recombineering
Authors: Bian Xiaoying , Huang Fan , Stewart Francis A. , Xia Liqiu , Zhang Youming , Müller Rolf
Published: August 2012

The reconstruction of a natural product biosynthetic pathway from bacteria in a vector and subsequent heterologous expression in a technically amenable microbial system represents an efficient alternative to empirical traditional methods for functional discovery, yield improvement, and genetic engineering to produce “unnatural” derivatives. However, the traditional cloning procedure based on genomic library construction and screening are complicated due to the large size (>10 kb) of most biosynthetic pathways. Here, we describe the direct cloning of a partial syringolin biosynthetic gene cluster (sylCDE, 19 kb) from a digested genomic DNA mixture of Pseudomonas syringae into a plasmid in which sylCDE is under the control of an inducible promoter by one step linear‐plus‐linear homologous recombination (LLHR) in Escherichia coli. After expression in E. coli GB05‐MtaA, two new syringolin derivatives were discovered. The complete syringolin gene cluster was assembled by addition of sylAB and exchange of a synthetic bidirectional promoter against the native promoter to drive sylB and sylC expression by using Red/ET recombineering. The varying production distribution of syringolin derivatives showed the different efficiencies of native and synthetic promoters in E. coli. The successful reconstitution and expression of the syringolin biosynthetic pathway shows that Red/ET recombineering is an efficient tool to clone and engineer secondary metabolite biosynthetic pathways.
Synthesis, Characterization, and Use of NbV/CeIV‐Mixed Oxides in the Direct Carboxylation of Ethanol by using Pervaporation Membranes for Water Removal
Authors: Dibenedetto Angela , Aresta Michele , Angelini Antonella , Ethiraj Jayashree , Aresta Brunella Maria
Published: August 2012

New catalytic systems based on ceria have been used in the direct carboxylation of ethanol. The catalytic behavior of Al2O3and Nb2O5loaded ceria is compared, the latter showing a better performance. A morphological and structural study has been carried out on Nb2O5/CeO2catalysts in order to explain their behavior in catalysis. Pervaporation membranes have been used for water separation. The synthesis of diethylcarbonate (DEC) has been carried out either in a liquid phase (ethanol) pressurized with CO2or in supercritical conditions. A set‐up has been developed that allows the production of quite pure DEC (>90 %) with recycling of CO2and ethanol.
β‐D‐Glucosyl Conjugates of Highly Potent Inhibitors of Blood Coagulation Factor Xa Bearing 2‐Chorothiophene as a P1 Motif
Authors: Lopopolo Gianfranco , de Candia Modesto , Panza Luigi , Romano Maria Rosaria , Lograno Marcello Diego , Campagna Francesco , Altomare Cosimo
Published: August 2012

We synthesized a novel O‐glucoside of the recently reported potent factor Xa (fXa) inhibitor 1, which bears a 5‐chlorothien‐2‐yl moiety and 1‐isopropylpiperidine as fragments that bind the S1 and S4 enzyme pockets, respectively. A β‐D‐glucosyl unit was conjugated through an ether‐linked C3‐alkyl spacer to the central phenyl ring of 1. The synthesized β‐D‐glucose‐based compound 16 achieved picomolar inhibitory potency against human fXa (Ki=60 pM) and high selectivity over thrombin and other serine proteases. In addition to the chlorothienyl S1 binder, a large gain in ΔG resulted from the addition of protonated 1‐isopropylpiperidine (ΔΔG=29.7–30.5 kJ mol−1), which should bind to the aromatic S4 pocket through efficient cation–π and CH⋅⋅⋅π interactions. Instead, the C3‐alkyl‐linked glucose fragment, which is likely directed toward the solvent outside the enzyme binding site, improves ΔG by an average of 2.9–3.8 kJ mol−1. Compound 16 showed sub‐micromolar in vitro anticoagulant activity, as assessed by prothrombin time (PT) and activated thromboplastin time (aPTT) clotting assays in pooled human plasma (PT2 and aPTT2 equal to 0.135 and 0.389 μM, respectively). Although compound 16 was 1.4‐fold less active than parent compound 1 in the ex vivo anticoagulant assay in mice, it showed a significant (1.6‐fold) prolongation of PT relative to controls (P<0.05) 60 min after oral dosing (75 mg kg−1).
Molecular Organization of Various Collagen Fragments as Revealed by Atomic Force Microscopy and Diffusion‐Ordered NMR Spectroscopy
Authors: Stötzel Sabine , Schurink Marloes , Wienk Hans , Siebler Uschi , Burg‐Roderfeld Monika , Eckert Thomas , Kulik Bianca , Wechselberger Rainer , Sewing Judith , Steinmeyer Jürgen , Oesser Steffen , Boelens Rolf , Siebert Hans‐Christian
Published: August 2012

Heterogeneous mixtures of collagen fragments can be used as nutrition supplement or as key ingredients for ointments with therapeutic relevance in wound healing. Some mixtures of collagen fragments are referred to as collagen hydrolysates owing to the production process with hydrolytic enzymes. Since the precise composition of collagen hydrolysates is generally unknown, it is of interest to analyze samples containing various collagen fragments with appropriate biophysical methods. Any product optimization without a profound knowledge concerning the size and the molecular weight distribution of its components is nearly impossible. It turned out that a combination of AFM methods with NMR techniques is exceptionally suited to examine the size range and the aggregation behavior of the collagen fragments in the hydrolysates of fish, jellyfish, chicken, porcine and bovine collagen. Supported by molecular modeling calculations, the AFM and NMR experiments provide a detailed knowledge about the composition of collagen hydrolysates and collagen ointments. Furthermore, the data allow a correlation between the size of the fragments and their potential bioactivity.
Bicarbonate efflux via GABAA receptors depolarizes membrane potential and inhibits two‐pore domain potassium channels of astrocytes in rat hippocampal slices
Authors: Ma Bao‐Feng , Xie Min‐Jie , Zhou Min
Published: August 2012

Increasing evidence indicates the functional expression of ionotropic γ‐aminobutyric acid receptor (GABAA‐R) in astrocytes. However, it remains controversial in regard to the intracellular Cl− concentration ([Cl−]i) and the functional role of anion‐selective GABAA‐R in astrocytes. In gramicidin perforated‐patch recordings from rat hippocampal CA1 astrocytes, GABA and GABAA‐R‐specific agonist THIP depolarized astrocyte membrane potential (Vm), and the THIP‐induced currents reversed at the voltages between −75.3 and −78.3 mV, corresponding to a [Cl−]i of 3.1–3.9 mM that favored a passive distribution of Cl− anions across astrocyte membrane. Further analysis showed that GABAA‐R‐induced Vm depolarization was ascribed to HCO3− efflux, while a passively distributed Cl− mediated no net flux or influx of Cl− that leads to an unchanged or hyperpolarized Vm. In addition to a rapidly activated GABAA‐R current component, GABA and THIP also induced a delayed inward current (DIC) in 63% of astrocytes. The DIC became manifest after agonist withdrawal and enhanced in amplitude with increasing agonist application duration or concentrations. Astrocytic two‐pore domain K+ channels (K2Ps), especially TWIK‐1, appeared to underlie the DIC, because (1) acidic intracellular pH, as a result of HCO3− efflux, inhibited TWIK‐1, (2) the DIC remained in the Cs+ recording solutions that inhibited conventional K+ channels, and (3) the DIC was completely inhibited by 1 mM quinine but not by blockers for other cation/anion channels. Altogether, HCO3− efflux through activated GABAA‐R depolarizes astrocyte Vm and induces a delayed inhibition of K2Ps K+ channels via intracellular acidification. © 2012 Wiley Periodicals, Inc.
Efficient 18F‐Labeling of Synthetic Exendin‐4 Analogues for Imaging Beta Cells
Authors: Keliher Edmund J. , Reiner Thomas , Thurber Greg M. , Upadhyay Rabi , Weissleder Ralph
Published: August 2012

A number of exendin derivatives have been developed to target glucagon‐like peptide 1 (GLP‐1) receptors on beta cells in vivo. Modifications of exendin analogues have been shown to have significant effects on pharmacokinetics and, as such, have been used to develop a variety of therapeutic compounds. Here, we show that an exendin‐4, modified at position 12 with a cysteine conjugated to a tetrazine, can be labeled with 18F‐trans‐cyclooctene and converted into a PET imaging agent at high yields and with good selectivity. The agent accumulates in beta cells in vivo and has sufficiently high accumulation in mouse models of insulinomas to enable in vivo imaging.
Correction of topographic artefacts of ToF‐SIMS element distributions
Authors: Ziegler Georg , Hutter Herbert
Published: August 2012

Images of time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) element distributions at the sample surface may be distorted when dealing with topographically structured samples and an oblique primary ion beam angle. This distortion becomes problematic if topographic feature heights exceed the primary ion beam diameter. Such topographic features may stem from initial topography, but they can also be introduced through differential sputtering of the sample during depth profiling. Current ToF‐SIMS software cannot take sample topography or differential sputtering into account. Instead, it assumes a flat surface and the same constant sputter rate for the whole sample which results in laterally and vertically distorted element distributions in depth profiles. Both of these negative effects are demonstrated using a thin layer system. We propose an algorithm to correct both kinds of defects for 2D and 3D ToF‐SIMS element distributions by combining them with topographic information. Copyright © 2012 John Wiley & Sons, Ltd.
Embryonic NANOG Activity Defines Colorectal Cancer Stem Cells and Modulates through AP1- and TCF-dependent Mechanisms
Authors: Ibrahim Elsayed E. , Babaei-Jadidi Roya , Saadeddin Anas , Spencer-Dene Bradley , Hossaini Sina , Abuzinadah Mohammed , Li Ningning , Fadhil Wakkas , Ilyas Mohammad , Bonnet Dominique , Nateri Abdolrahman S.
Published: August 2012

Embryonic NANOG (NANOG1) is considered as an important regulator of pluripotency while NANOGP8 (NANOG-pseudogene) plays a role in tumorigenesis. Herein, we show NANOG is expressed from both NANOG1 and NANOGP8 in human colorectal cancers (CRC). Enforced NANOG1-expression increases clonogenic potential and tumor formation in xenograft models, although it is expressed only in a small subpopulation of tumor cells and is colocalized with endogenous nuclear β-cateninHigh. Moreover, single NANOG1-CRCs form spherical aggregates, similar to the embryoid body of embryonic stem cells (ESCs), and express higher levels of stem-like Wnt-associated target genes. Furthermore, we show that NANOG1-expression is positively regulated by c-JUN and β-catenin/TCF4. Ectopic expression of c-Jun in murine ApcMin/+-ESCs results in the development of larger xenograft tumors with higher cell density compared to controls. Chromatin immunoprecipitation assays demonstrate that c-JUN binds to the NANOG1-promoter via the octamer M1 DNA element. Collectively, our data suggest that β-Catenin/TCF4 and c-JUN together drive a subpopulation of CRC tumor cells that adopt a stem-like phenotype via the NANOG1-promoter.
Tracing Synaptic Connectivity onto Embryonic Stem Cell-Derived Neurons
Authors: Garcia Isabella , Huang Longwen , Ung Kevin , Arenkiel Benjamin R.
Published: August 2012

Transsynaptic circuit tracing using genetically modified rabies virus (RV) is an emerging technology for identifying synaptic connections between neurons. Complementing this methodology, it is now possible to assay the basic molecular and cellular properties of neuronal lineages derived from embryonic stem cells (ESCs) in vitro, and these properties are under intense investigation toward devising cell replacement therapies. Here, we report the generation of a novel mouse ESC (mESC) line that harbors the genetic elements to allow RV-mediated transsynaptic circuit tracing in ESC-derived neurons and their synaptic networks. To facilitate transsynaptic tracing, we have engineered a new reporter allele by introducing cDNA encoding tdTomato, the Rabies-G glycoprotein, and the avian TVA receptor into the ROSA26 locus by gene targeting. We demonstrate high-efficiency differentiation of these novel mESCs into functional neurons, show their capacity to synaptically connect with primary neuronal cultures as evidenced by immunohistochemistry and electrophysiological recordings, and show their ability to act as source cells for presynaptic tracing of neuronal networks in vitro and in vivo. Together, our data highlight the potential for using genetically engineered stem cells to investigate fundamental mechanisms of synapse and circuit formation with unambiguous identification of presynaptic inputs onto neuronal populations of interest.
Measuring the invisible Higgs width at the 7 and 8 TeV LHC
Authors: Bai Yang , Draper Patrick , Shelton Jessie
Published: August 2012

Abstract

The LHC is well on track toward the discovery or exclusion of a light Standard Model (SM)-like Higgs boson. Such a Higgs has a very small SM width and can easily have large branching fractions to physics beyond the SM, making Higgs decays an excellent opportunity to observe new physics. Decays into collider-invisible particles are particularly interesting as they are theoretically well motivated and relatively clean experimentally. In this work we estimate the potential of the 7 and 8 TeV LHC to observe an invisible Higgs branching fraction. We analyze three channels that can be used to directly study the invisible Higgs branching ratio at the 7 TeV LHC: an invisible Higgs produced in association with (i) a hard jet; (ii) a leptonic Z; and (iii) forward tagging jets. We find that the last channel, where the Higgs is produced via weak boson fusion, is the most sensitive, allowing branching fractions as small as 40 % to be probed at 20 inverse fb for masses in the range between 120 and 170 GeV, including in particular the interesting region around 125 GeV. We provide an estimate of the 8 TeV LHC sensitivity to an invisibly-decaying Higgs produced via weak boson fusion and find that the reach is comparable to but not better than the reach at the 7 TeV LHC. We further estimate the discovery potential at the 8 TeV LHC for cases where the Higgs has substantial branching fractions to both visible and invisible final states.