bluuebunny/crossref_metadata_2025 huggingface dataset:
Genome-wide investigation reveals high evolutionary rates in annual model plants
Authors: Yue Jia-Xing , Li Jinpeng , Wang Dan , Araki Hitoshi , Tian Dacheng , Yang Sihai
Published: November 2010

Background

Rates of molecular evolution vary widely among species. While significant deviations from molecular clock have been found in many taxa, effects of life histories on molecular evolution are not fully understood. In plants, annual/perennial life history traits have long been suspected to influence the evolutionary rates at the molecular level. To date, however, the number of genes investigated on this subject is limited and the conclusions are mixed. To evaluate the possible heterogeneity in evolutionary rates between annual and perennial plants at the genomic level, we investigated 85 nuclear housekeeping genes, 10 non-housekeeping families, and 34 chloroplast genes using the genomic data from model plants including Arabidopsis thaliana and Medicago truncatula for annuals and grape (Vitis vinifera) and popular (Populus trichocarpa) for perennials.

Results

According to the cross-comparisons among the four species, 74-82% of the nuclear genes and 71-97% of the chloroplast genes suggested higher rates of molecular evolution in the two annuals than those in the two perennials. The significant heterogeneity in evolutionary rate between annuals and perennials was consistently found both in nonsynonymous sites and synonymous sites. While a linear correlation of evolutionary rates in orthologous genes between species was observed in nonsynonymous sites, the correlation was weak or invisible in synonymous sites. This tendency was clearer in nuclear genes than in chloroplast genes, in which the overall evolutionary rate was small. The slope of the regression line was consistently lower than unity, further confirming the higher evolutionary rate in annuals at the genomic level.

Conclusions

The higher evolutionary rate in annuals than in perennials appears to be a universal phenomenon both in nuclear and chloroplast genomes in the four dicot model plants we investigated. Therefore, such heterogeneity in evolutionary rate should result from factors that have genome-wide influence, most likely those associated with annual/perennial life history. Although we acknowledge current limitations of this kind of study, mainly due to a small sample size available and a distant taxonomic relationship of the model organisms, our results indicate that the genome-wide survey is a promising approach toward further understanding of the mechanism determining the molecular evolutionary rate at the genomic level.
Smoking prevalence, cessation rates and relapse rates in the Swiss HIV Cohort Study (SHCS)
Authors: Huber M , Ledergerber B , Jaccard R , Elzi L , Furrer H , Hirschel B , Cavassini M , Bernasconi E , Schmid P , Weber R
Published: November 2010

7‐11 November 2010, Tenth International Congress on Drug Therapy in HIV Infection, Glasgow, UK
Programa Bolsa Família: impacto das transferências sobre os gastos com alimentos em famílias rurais
Authors: Duarte Gisléia Benini , Sampaio Breno , Sampaio Yony
Published: November 2010

Programas de transferência condicionada de renda são políticas sociais correntemente empregadas para combater e reduzir a pobreza em diversos países. No curto prazo, esses programas visam aliviar os problemas decorrentes da situação de pobreza, sendo que, no longo prazo, o objetivo é investir no capital humano, quebrando o ciclo intergeracional da pobreza. Estudos têm sido realizados para avaliar os impactos desses programas sobre variáveis como freqüência escolar, trabalho infantil, gastos com alimentação, entre outros. Este trabalho avalia o impacto da transferência de renda do Programa Bolsa Família sobre os gastos com alimentos de famílias rurais. As estimações foram feitas com base no método de Propensity Score Matching (PSM), que corrige para o viés de seleção amostral. Os resultados mostram que o valor médio das despesas anuais para as famílias beneficiárias supera em R$ 246 os gastos totais das famílias não-participantes. Considerando que a média anual recebida por essas famílias é de R$ 278, pode-se inferir que 88% desse valor é utilizado para consumo de alimento. Portanto, o programa de transferência condicionada Bolsa Família exerce um impacto positivo sobre o consumo de alimentos dessas famílias selecionadas.
Dryland Soil Carbon and Nitrogen Influenced by Sheep Grazing in the Wheat–Fallow System
Authors: Sainju Upendra M. , Lenssen Andrew W. , Goosey Hayes B. , Snyder Erin , Hatfield Patrick G.
Published: November 2010

Sheep (Ovis aries) grazing during fallow for weed control in wheat (Triticum aestivum L.)–fallow systems may influence soil C and N levels and grain yields by returning part of consumed crop residue to the soil through feces and urine. We evaluated the effects of fallow management (sheep grazing [grazing], herbicide application [chemical], and tillage [mechanical]) for weed control and soil water conservation and cropping sequence (continuous spring wheat [CSW], spring wheat–fallow [SW‐F], and winter wheat–fallow [WW‐F]) on soil organic carbon (SOC), inorganic carbon (SIC), total nitrogen (STN), NH4–N, and NO3–N levels at the 0‐ to 120‐cm depth and wheat yield. The experiment was conducted in a Blackmore silt loam (fine‐silty, mixed, superactive, frigid Typic Argiustolls) from 2004 to 2008 in southwestern Montana. Annualized wheat grain and biomass yields were greater in CSW than in SW‐F and WW‐F and greater in 2004 than in other years. From 2004 to 2007, SOC concentration at 0‐ to 15‐cm declined by 2.99 g C kg−1 yr−1 In 2008, SOC content at 10 to 120 cm was greater in the mechanical or chemical than in the grazing treatment in CSW and SW‐F. The STN content at 0 to 5 cm was greater in the chemical and mechanical than in the grazing treatment but at 30 to 60 cm was greater in the grazing than in the chemical treatment in CSW. From 2004 to 2006, NO3–N content at 0 to 60 cm was greater in SW‐F or WW‐F than in CSW. In 2008, NO3–N content at 30 to 120 cm was greater in CSW and SW‐F than in WW‐F and at 60 to 90 cm was greater in the mechanical than in the chemical treatment. The SIC and NH4–N contents were largely not influenced by treatments. Continuous tillage, followed by reduced amount of wheat residue returned to the soil from 2004 to 2007 probably reduced soil C and N storage. In contrast, greater amount of N removed by wheat grain due to continuous cropping probably reduced soil NO3–N in CSW. For sustaining wheat yields and maintaining soil C and N levels, reduced tillage with continuous cropping and less intensive sheep grazing that increase the amount of wheat residue returned to the soil could be adopted.
The effect of different pre-mixtures in nutrition of fatteners
Authors: Zivkovic Branislav , Migdal W. , Kosovac O. , Radovic C. , Pejcic S.
Published: November 2010

We have been witnesses to import of numerous premixes produced by various
producers and of different quality in regard to concentration of ingredients
which are their main components. In our previous studies (Zivkovic et al.,
2010) we obtained results confirming that in use of domestic premix more
economically efficient production is realized in nutrition of sows and
piglets, so this research was carried out with objective to verify the
effects of several different imported premixes and those produced according
to domestic concept, in nutrition of growing-fattening pigs. Research was
performed on private farm in the vicinity of Sabac in Serbia. Nutrition of
fattening pigs using mixture which contained adequate premix of domestic
production improved the growth rate by 7.6% without any significant
difference in food conversion. Cost of feed when domestic premixes were used
in nutrition of fattening pigs was by 4.1% lower and value of realized pigs
by approx. 4.51% more favourable when domestic premixes were used in
nutrition of investigated animals. Dressing percentage of pigs on domestic
premixes was higher by 2.0%, and there was no difference in meatiness between
compared groups of animals in the experiment. In general, obtained results
showed that use of both types of compared premixes can be recommended, but it
is more economically efficient to use domestic premixes in nutrition of
fattening pigs.
Rheological behaviour of thermoplastic poly(ester-siloxane)s
Authors: Antic Vesna , Pergal Marija , Antic Malisa , Djonlagic Jasna
Published: November 2010

Two series of thermoplastic elastomers (TPES) based on poly(dimethylsiloxane), (PDMS) as the soft segment and poly(butylene terephthalate) (PBT) as the hard segment, were analyzed by dynamic mechanical spectroscopy. In the first TPES series the lengths of both hard and soft segments were varied while the mass ratio of the hard to soft segments was nearly constant (about 60 mass%). In the second series, the mass ratio of hard and soft segments was varied in the range from 60/40 to 40/60, with a constant length of soft PDMS segments. The influence of the structure and composition of TPESs on the rheological properties, such as complex dynamic viscosity, ?*, the storage, G?, and loss, G?, shear modulus as well as the microphase separation transition temperature, TMST, was examined. The obtained results showed that the storage modulus of the TPESs increased in a rubbery plateau region with increasing degree of crystallinity. The rheological measurements of TPESs also showed that a microphase reorganization occurred during the melting process. The microphase separation transition temperatures were in the range from 220 to 234 ?C. In the isotropic molten state, the complex dynamic viscosity increased with increasing both the content and lenght of hard PBT segments.
Municipalities Collaborating in Public Health: The Danish Smoking Prevention and Cessation Partnership
Authors: Andersen Pernille Tanggaard , Ansari Walid El , Rasmussen Hanna Barbara , Stock Christiane
Published: November 2010

This study explored the Smoking Prevention and Cessation Partnership (SPCP) which builds upon a collaboration between two Danish municipalities targeted at the prevention of tobacco smoking. The aim of the study was to describe the processes of SPCP, to examine the difficulties this collaboration faced, and to assess how these experiences could be used to improve future partnership collaboration. We employed qualitative methodology comprising 12 semi-structured one-to-one interviews with SPCP’s stakeholders and an analysis of the partnership documents and reports. The findings suggested that the main potentials of the partnership were the personal relations between the members and stakeholders with the possibilities of the creation of new connections with other actors. Barriers to successful partnership building were the implementation of the new Local Government Reform as a competing task, and that the two municipalities were heterogenic in respect to organizational issues and working methods. Other impediments included the lack of continuity in leadership, the lack of clarity regarding the form of collaboration and roles, as well as different expectations of the stakeholders. We conclude that four factors remain critical for partnerships. The first is the clarity of the collaborative effort. Second, partnerships need to take into account the structural circumstances and culture/value systems of all stakeholders. Third is the impact of contextual factors on the development of the partnership; and the fourth factor is the bearing of personal/individual factors on the partnership e.g., personal engagement in the project. Early attention to these four factors could contribute to more effective partnership working.
Synthesis of Non-Cytotoxic Poly(Ester-Amine) Dendrimers as Potential Solubility Enhancers for Drugs: Methotrexate as a Case Study
Authors: Soto-Castro Delia , Cruz-Morales Jorge A. , Apan María Teresa Ramírez , Guadarrama Patricia
Published: November 2010

This study describes the synthesis of two new families of dendrimers based on the esterification of N-alkylated 3-amine-1-propanol with two different cores, adipic acid (1st and 2nd generations) and ethylenediamine (generation 1.5), both with carboxylic acid end groups, offering a wide variety of further modifications at the periphery. According to the cytotoxic evaluation of the dendrimers and their possible degradation products within cell lines, these materials could be considered as innocuous. In preliminary studies, the synthesized dendrimers proved to be potential enhancers of solubility of highly hydrophobic drugs, like methotrexate, widely used in chemotherapy.
Stimulated Cellular Response of Novel Hybrid Network Structure Elastomers with Inorganic Short Chain Cross‐Links for Soft Tissue Reconstruction
Authors: Shah Jinesh S. , Girase Bhupinder , Thein‐Han Wah Wah , Misra R. Devesh K.
Published: November 2010

The flexible and highly ductile silicone elastomer widely used as a soft‐tissue substitute for joint reconstruction and replacement fragments prematurely because of low tensile strength and inadequate bone build‐up around the implants. In this regard, an excellent vehicle to favorably modulate cellular response and retain intrinsic elastic recovery of soft tissue implants is to consider hybrid network structure elastomers with inorganic short chain cross‐links. The concept involves covalently linking nanocrystalline titania with a bi‐functional agent, acrylic acid, which has a carboxylic group to coordinate with titania and a vinyl group to form short chain cross‐links as an integral part of the silicone network during curing at elevated pressure. This approach provides high strength‐at‐break and undiminished intrinsic ductility of silicone elastomer and high cytocompatibility. Interestingly, cellular response is favorably modulated, as described here. The biologic response in terms of initial cell attachment, cell viability, and proliferation was consistently greater in relation to stand alone silicone elastomer such that cell spreading, morphology, and density were distinctly different. Pre‐osteoblasts grown on hybrid network structure elastomers were widely spread on the surface as a sheet after a culture time of 24 h. In contrast, these features were less pronounced on the stand alone silicone elastomer. Furthermore, immunofluorescence study illustrated distinct fibronectin expression level, stronger vinculin focal adhesion contacts associated with abundant actin stress fibers in pre‐osteoblasts grown on hybrid network structure elastomer compared to stand alone silicone elastomer, implying enhanced cell–substrate interactions. This finding was consistent with the observation of total protein content and sodium dodecyl sulfate polyacrylamide gel analysis.

Based on the study described here, our hypothesis is that silicone–titania network structure elastomer with high strength–high ductility combination and favorable cellular response is a model hybrid network structure elastomer for joint reconstruction and soft tissue substitution. The integration of cellular and molecular biology with materials science and engineering aspects described here provides a new direction toward the development of new generation of hybrid network structure silicone elastomer. This subject is germane from the view point of fundamental understanding and from the view of hybrid elastomers as soft tissue reconstruction.
The Contribution of DOPA to Substrate–Peptide Adhesion and Internal Cohesion of Mussel‐Inspired Synthetic Peptide Films
Authors: Anderson Travers H. , Yu Jing , Estrada Abril , Hammer Malte U. , Waite J. Herbert , Israelachvili Jacob N.
Published: November 2010

Mussels use a variety of 3, 4‐dihydroxyphenyl‐L‐alanine (DOPA) rich proteins specifically tailored to adhering to wet surfaces. Synthetic polypeptide analogues of adhesive mussel foot proteins (specifically mfp‐3) are used to study the role of DOPA in adhesion. The mussel‐inspired peptide is a random copolymer of DOPA and N5‐ (2‐hydroxyethyl)‐L‐glutamine synthesized with DOPA concentrations of 0–27 mol% and molecular weights of 5.9–7.1 kDa. Thin films (3–5 nm thick) of the mussel‐inspired peptide are used in the surface forces apparatus (SFA) to measure the force–distance profiles and adhesion and cohesion energies of the films in an acetate buffer. The adhesion energies of the mussel‐inspired peptide films to mica and TiO2 surfaces increase with DOPA concentration. The adhesion energy to mica is 0.09 μJ m−2 molDOPA−1 and does not depend on contact time or load. The adhesion energy to TiO2 is 0.29 μJ m−2 molDOPA−1 for short contact times and increases to 0.51 μJ m−2 molDOPA−1 for contact times >60 min in a way suggestive of a phase transition within the film. Oxidation of DOPA to the quinone form, either by addition of periodate or by increasing the pH, increases the thickness and reduces the cohesion of the films. Adding thiol containing polymers between the oxidized films recovers some of the cohesion strength. Comparison of the mussel‐inspired peptide films to previous studies on mfp‐3 thin films show that the strong adhesion and cohesion in mfp‐3 films can be attributed to DOPA groups favorably oriented within or at the interface of these films.
High‐Performance Organic Solar Cells with Spray‐Coated Hole‐Transport and Active Layers
Authors: Girotto Claudio , Moia Davide , Rand Barry P. , Heremans Paul
Published: November 2010

In this study, we report high performance organic solar cells with spray coated hole‐transport and active layers. With optimized ink formulations we are able to deposit films with controlled thickness and very low surface roughness (<10 nm).

Specifically we deposit smooth and uniform 40 nm thick films of poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) as well as films composed of a mixture of poly(3‐hexyl thiophene) (P3HT) and the C60‐derivative (6,6)‐phenyl C61‐butyric acid methyl ester (PCBM) with thicknesses in the range 200–250 nm.

To control film morphology, formation and thickness, the optimized inks incorporate two solvent systems in order to take advantage of surface tension gradients to create Marangoni flows that enhance the coverage of the substrate and reduce the roughness of the film.

Notably, we achieve fill factors above 70% and attribute the improvement to an enhanced P3HT crystallization, which upon optimized post‐drying thermal annealing results in a favorable morphology. As a result, we could extend the thickness of the layer to several hundreds of nanometers without noticing a substantial decrease of the transport properties of the layer.

By proper understanding of the spreading and drying dynamics of the inks we achieve spray coated devices with power conversion efficiency of 3.75%, with fill factor, short circuit current and open circuit voltage of 70%, 9.8 mA cm−2 and 550 mV, respectively.
Swelling behavior of novel protein‐based superabsorbent nanocomposite
Authors: Bagheri Marandi G. , Mahdavinia G. R. , Ghafary Sh.
Published: November 2010

A novel superabsorbent nanocomposite based on hydrolyzed collagen was synthesized by simultaneously graft copolymerization of 2‐acrylamido‐2‐methylpropane sulfonic acid (AMPS) and acrylamide (AAm). Sodium montmorilonite (Na‐MMt) was used as clay. Methylenebisacrylamide (MBA) and ammonium persulfate (APS) were used as crosslinker and initiator, respectively. The effect of reaction variables such as nanoclay content, MBA and APS concentrations as well as the AMPS/AAm weight ratio on the water absorbency of nanocomposites was investigated. Although the water absorbency was decreased by increasing of MBA concentration, an optimum swelling capacity was achieved for clay, APS, and AMPS/AAm variables. The structure of nanocomposite was identified using FTIR spectroscopy, XRD patterns, and scanning electron microscopy graphs. The effect of swelling media comprising various dissolved salts and different pHs was studied. Also, water retention capacity was studied, and the results showed that inclusion of Na‐MMt nanoclay causes an increase in water retention under heating. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
An intersection turning movement estimation procedure based on path flow estimator
Authors: Chen Anthony , Chootinan Piya , Ryu Seungkyu , Lee Ming , Recker Will
Published: November 2010

Estimation of intersection turning movements is one of the key inputs required for a variety of transportation analysis, including intersection geometric design, signal timing design, traffic impact assessment, and transportation planning. Conventional approaches that use manual techniques for estimation of turning movements are insensitive to congestion. The drawbacks of the manual techniques can be amended by integrating a network traffic model with a computation procedure capable of estimating turning movements from a set of link traffic counts and intersection turning movement counts. This study proposes using the path flow estimator, originally used to estimate path flows (hence origin–destination flows), to derive not only complete link flows, but also turning movements for the whole road network given some counts at selected roads and intersections. Two case studies using actual traffic counts are used to demonstrate the proposed intersection turning movement estimation procedure. Copyright © 2010 John Wiley & Sons, Ltd.
Interdiffusion in Systems with Structural Vacancies
Authors: Leute V. , Zeppenfeld A.
Published: November 2010

The cation interdiffusion in quasibinary II—VI/III—VI‐systems was investigated by electron microprobe measurements. The measured diffusion profiles are compared with calculated probability distributions of clusters containing structural vacancies. The effect of these clusters on the formation of ordered phases and on the growth rate of these phases during the interdiffusion is discussed.
Investigation of Solid State Matrices via 2H NMR on Mobile Deuterated Guest Molecules
Authors: Rössler Ernst , Taupitz Matthias , Vieth Hans‐Martin
Published: November 2010

Deuterated benzene and hexamethylbenzene (HMB) molecules are used as probes to study molecular crystals and organic glasses via 2H NMR. The rotational mobility of the guest molecules causes fast nuclear spin polarization which enables spin‐lattice relaxation and line shape investigations in a temperature range of 10—300 K. The parameters of the molecular reorientation of the guests are investigated for the different matrices. HMB as a guest in hexachlorobenzene is characterized by an exponential relaxation and by an increase of the activation energy for the sixfold rotation by a factor of 2 as compared to neat HMB. A homogeneous mixing is found up to a concentration of about 7%. For the glassy matrices significant non‐exponential relaxation is observed corresponding to motional heterogeneities in the disordered systems. The relaxation is described by a convolution of exponential decays and a distribution of relaxation times which is related to a distribution of activation energies for the guest motion. Different shapes for the relaxation function at high and low temperatures prove an asymmetric distribution with its maximum on the low energy side. The deconvolution procedure leads to detailed information because two different Laplace transformations are involved. Below 40 K the 2H NMR line shape of HMB in the different matrices is determined by tunneling of the methyl groups. An increase of the tunneling frequency from about 10 kHz in neat HMB to more than 2 MHz in the other host systems is estimated.
Optical Hole Burning and Thermal Irreversibility of Non‐Ergodic Systems: Polymers, Proteins, Glasses
Authors: Friedrich J.
Published: November 2010

A spectral hole is used to probe configurational dynamics of non‐ergodic systems far below the glass transition temperature.
Precursor Stages of α‐Precipitation in Dilute CuCo Alloys
Authors: Wagner W.
Published: November 2010

The system CuCo repeatedly was chosen for studies to test the validity of classical nucleation theory in metallic systems, with the conclusion that the nucleation reaction can well be described by the classical model. The present investigation by Small Angle Neutron Scattering aims to give insight into the atomic rearrangement occurring during the course of nucleation. CuCo‐alloys containing 0.5, 0.8 and 2.0 at.% Co were chosen for this study. The results give evidence for precursor stages of decomposition prior to the precipitation of the fcc Co‐rich α‐phase, characterized as concentration fluctuations low in amplitude, but large in extent as compared with the later forming α‐precipitates. The fluctuations obviously stimulate the α‐phase precipitation, giving rise to nucleation rates significantly larger than predicted by classical nucleation theory, with smallest stable precipitates which are 2 to 5 times as large as the theoretically predicted critical nuclei.
Mesomorphism and Luminescence Properties of Platinum(II) Complexes with Tris(alkoxy)phenyl‐Functionalized Pyridyl Pyrazolate Chelates
Authors: Liao Ching‐Ting , Chen Hsiu‐Hui , Hsu Hsiu‐Fu , Poloek Anurach , Yeh Hsiu‐Hsuan , Chi Yun , Wang Kang‐Wei , Lai Chin‐Hung , Lee Gene‐Hsiang , Shih Chun‐Wei , Chou Pi‐Tai
Published: November 2010

A series of new mesomorphic platinum(II) complexes 1–4 bearing pyridyl pyrazolate chelates are reported herein. In this approach, pyridyl azolate ligands have been strategically functionalized with tris(alkoxy)phenyl groups with various alkyl chain lengths. As a result, they are ascribed to a class of luminescent metallomesogens that possess distinctive morphological properties, such as their intermolecular packing arrangement and their associated photophysical behavior. In CH2Cl2, independent of the applied concentration in the range 10−6–10−3 M, all PtII complexes exhibit bright phosphorescence centered at around 520 nm, which is characteristic for monomeric PtII complexes. In stark contrast, the single‐crystal X‐ray structure determination of [Pt(C4pz)2] (1) shows the formation of a dimeric aggregate with a notable Pt⋅⋅⋅Pt contact of 3.258 Å. Upon heating, all PtII complexes 1–4 melted to form columnar suprastructures, for which similar intracolumnar Pt⋅⋅⋅Pt distances of approx. 3.4–3.5 Å are observed within an exceptionally wide temperature range (>250 °C), according to the powder XRD data. Upon casting into a neat thin film at RT, the luminescence of 1–4 is dominated by a red emission that spans 630–660 nm, which originates from the one‐dimensional, chainlike structure with Pt–Pt interaction in the ground state. Taking complex 4 as a representative, the emission intensity and wavelength were significantly decreased and blueshifted, respectively, on heating from RT to 250 °C. Further heating to liquefy the sample alters the red emission back to the green phosphorescence of the monomer. The results highlight the pivotal role of tris(alkoxy)phenyl groups in the structural versus luminescence behavior of these PtII complexes.
Organic Ligand‐Free Alkylation of Amines, Carboxamides, Sulfonamides, and Ketones by Using Alcohols Catalyzed by Heterogeneous Ag/Mo Oxides
Authors: Cui Xinjiang , Zhang Yan , Shi Feng , Deng Youquan
Published: November 2010

Complicated and expensive organic ligands are normally essential in fine chemical synthesis at preparative or industrial levels. The synthesis of fine chemicals by using heterogeneous catalyst systems without additive organic ligand is highly desirable but severely limited due to their poor generality and rigorous reaction conditions. Here, we show the results of carbon–nitrogen or carbon–carbon bond formation catalyzed by an Ag/Mo hybrid material with specific Ag6Mo10O33 crystal structure. 48 nitrogen‐ or oxygen‐containing compounds, that is, amines, carboxamides, sulfonamides, and ketones, were successfully synthesized through a borrowing‐hydrogen mechanism. Up to 99 % isolated yields were obtained under relatively mild conditions without additive organic ligand. The catalytic process shows promise for the efficient and economic synthesis of amine, carboxamide, sulfonamide, and ketone derivatives because of the simplicity of the system and ease of operation.
Momentum, Heat and Mass Transfer in Exhaust Gas Sensors at Engine Operating Conditions
Authors: Brück M. , Klett S. , Göll S. , Piesche M.
Published: November 2010

Eine optimale Entwicklung von Abgassensoren erfordert die Kenntnis aller für Funktion und Belastung relevanter Größen. Ein messtechnischer Zugang ist schwierig, teilweise unmöglich. Ziel war daher die Entwicklung eines validierten Simulationsmodells zur Vorhersage des Betriebsverhaltens. Die Berechnung konvektiver Transportvorgänge zur Oberfläche des Sensors erfolgt durch Kopplung einer 1D‐Ladungswechsel‐ mit einer 3D‐Strömungssimulation. Hieraus resultieren Randbedingungen für ein 1D‐Modell zur Beschreibung des Stofftransports im Inneren des Sensors. Es wurden zwei Sondensignale berechnet.
Enhancement in gas holdup in bubble columns through use of vibrating internals
Authors: Balamurugan V. , Subbarao D. , Roy Shantanu
Published: November 2010

Including internals in bubble columns is known to enhance the gas holdup. In this paper, a method to achieve this objective substantially has been proposed via the use of vibrating helical spring internals. Experimental observations on effect of vibrating internals such as vibrating helical springs on gas holdup in bubble columns are presented. Effects of superficial gas velocity, H/D ratio (height of the static liquid to column diameter ratio), volume fraction of helical springs, and thickness of the helical spring wires on hydrodynamics parameters are studied. Increase in gas holdup up to 135% is observed by using vibrating helical spring internals in bubble columns compared to bubble columns without internals. This method offers a simple, cost‐effective, and easy way to enhance gas holdup even at high gas fluxes. It has been reported that this enhancement stems from the fact that the vibrating springs breakup the gas into fine bubbles, which effectively reduces their rise velocity and enhances their average residence time in the liquid column.
Design and assessment of a novel static mixer
Authors: Al‐Atabi Mushtak
Published: November 2010

This paper examines the performance of a novel static mixer comprising a circular tube fitted with eight alternating equi‐spaced semicircular rigid insert (baffles) as the mixer elements. Experiments were carried out to obtain the coefficient of variance (CoV) for the mixing of two streams of water and brine for Reynolds number between 60 and 700. Decreasing the baffles clearance ratio significantly reduces the CoV but at a cost of an increase in the pressure drop across the static mixer. The presence of the mixing elements (baffles) promotes a non‐laminar, turbulent‐like flow which considerably enhances the mixing. The static mixer described here represents a cost effective, easy to manufacture, low maintenance, and flexible alternative to the more sophisticated static mixers currently in use.
Precipitation of pharmaceuticals using a supercritical anti‐solvent (SAS) dechnique: A preliminary study
Authors: Imsanguan Photchanathip , Yanothai Tanawan , Pongamphai Suwassa , Douglas Supaporn , Teppaitoon Wittaya , Douglas Peter L.
Published: November 2010

The aims of this research were to investigate the applicability of the supercritical anti‐solvent (SAS) process on the precipitation of pharmaceuticals (andrographolide and acetaminophen). In particular, the goal of this research was to study the influence of pressure at 10 and 24 MPa on particle characteristics (morphology, crystalline structure, polymorphic form, size, size distribution, and precipitation yield), and to compare the precipitation efficiency of SAS process and evaporation process. Scanning electron microscope (SEM), X‐ray diffraction (XRD), and high performance liquid chromatography (HPLC) showed a significant change in particle size, size distribution, morphology, and precipitation yield, respectively. From an analysis of the results it was found that the crystal size of andrographolide and acetaminophen decreased with increasing pressure. The morphology of andrographolide particles changed from slice‐like to column‐like when the pressure was increased. On the other hand, the acetaminophen particles obtained were found to be monoclinic form (I) under both operating pressures. The SAS process produced small uniform shaped crystals, with a narrow size distribution, high precipitation yield and selective precipitation were also observed.
Evidence of a Folding Intermediate in RNase H from Single‐Molecule FRET Experiments
Authors: Rieger Robert , Kobitski Andrei , Sielaff Hendrik , Nienhaus G. Ulrich
Published: November 2010

Single‐molecule Förster resonance energy transfer (FRET) experiments were performed on the enzyme RNase H specifically labeled with a FRET dye pair and diffusing freely in solutions containing between 0 and 6 M of the chemical denaturant GdmCl. We measured FRET efficiency histograms with high statistical accuracy to identify the well‐known folding intermediate of RNase H, which escaped observation in our previous smFRET studies on immobilized preparations. Even with excellent data statistics, a folding intermediate is not obvious from the raw data. However, it can be uncovered by a global fitting procedure applied to the FRET histograms at all 22 GdmCl concentrations, in which a number of parameters were constrained. Most importantly, the fractional populations of the folded, unfolded and intermediate states were coupled by assuming the Boltzmann relation and a linear dependence of the free energies on the GdmCl concentration. The analysis not only resolves the apparent discrepancy with other data on RNase H, but yields free energy differences between the three populations in agreement with literature data. In addition, it removes the strong and unexplained broadening of the unfolded‐state distribution in the transition region that was seen earlier in the two‐state analysis.
Enhancement of proliferation and downregulation of TRAIL expression on CD8+ T cells by IL‐21
Authors: Melief Cornelis J. M. , Schoenberger Stephen P.
Published: November 2010

Mounting evidence indicates that the cytokine IL‐21 can significantly enhance the survival of CD8+ T lymphocytes. Given that CD4+ T lymphocytes constitute the main cellular source for IL‐21 in vivo, it is tempting to speculate a direct role in mediating the “help” provided by these CD4+ T cells to the CD8 response. A new report in this issue of the European Journal of Immunology advances this notion by showing that CD8+ T cells lacking the IL‐21 receptor phenocopy those primed in the absence of CD4+ T cells (the so‐called “helpless” CD8+ T cells) in their induction of the pro‐apoptotic factor TRAIL. This finding helps to define the role of IL‐21 in the CD8 response, and raises new questions relevant for achieving a broader understanding of this multifunctional cytokine.
Cover Picture: Eur. J. Immunol. 11/10
Authors: Hamel Keith M. , Cao Yanxia , Wang Yumei , Rodeghero Rachel , Kobezda Tamas , Chen Lieping , Finnegan Alison
Published: November 2010

The cover image of this issue consists of an hematoxylin and eosin staining of a sagittal section of hind paw harvested from a wild‐type BALB/c mouse 6 weeks after proteoglycan (PG)‐dimethyldioctadecyl‐ammonium bromide (DDA) immunization, and is taken from Hamel et al. (pp. 3117–3127). In this article, the authors examine the role of the programmed death (PD)‐1 ligand, B7‐H1, in the development of PG‐induced arthritis (PGIA). The authors show that B7‐H1−/− mice exhibit exacerbated PGIA and increased Th1 CD4+ T‐cell responses, while the PG‐specific antibody response in these mice is diminished.
Electrophoretically mediated microanalysis assay for sirtuin enzymes
Authors: Fan Yi , Scriba Gerhard K. E.
Published: November 2010

An electrophoretically mediated microanalysis (EMMA) assay for the human sirtuin SIRT1 has been developed using 9‐fluorenylmethoxycarbonyl (Fmoc)‐labeled peptides, i.e. Fmoc‐KK(Ac)‐NH2, Fmoc‐KK(Ac)L‐NH2 and Fmoc‐RHKK(Ac)‐NH2, as substrates. The partial filling mode was applied due to the incompatibility between the incubation buffer, pH 8.0, and the BGE that had a pH of 2.7 or 2.3 depending on the analytes. Incubation and subsequent analyte separation were carried out in a 37/30 cm, 50 μm id fused‐silica capillary at 37°C. An injection sequence of incubation buffer, enzyme, substrate, enzyme and incubation buffer was selected because the electrophoretic mobility of SIRT1 was not known. The assay was optimized with regard to the length of the injected plugs, the mixing voltage and mixing time as well as the activity (concentration) of SIRT1. The EMMA assay was subsequently applied to the determination of the Michaelis–Menten constants, Km, and the maximum velocity, Vmax, as well as the determination of the inhibitory constants, IC50, of inhibitors. Data obtained with the in‐capillary assay were in accordance with the literature data or an offline SIRT1 assay.
Cost‐effective interrogation of single nucleotide polymorphisms using the mismatch amplification mutation assay and capillary electrophoresis
Authors: Price Erin P. , Matthews Molly A. , Beaudry Jodi A. , Allred Jonathan L. , Schupp James M. , Birdsell Dawn N. , Pearson Talima , Keim Paul
Published: November 2010

The ability to characterize SNPs is an important aspect of many clinical diagnostic, genetic and evolutionary studies. Here, we designed a multiplexed SNP genotyping method to survey a large number of phylogenetically informative SNPs within the genome of the bacterium Bacillus anthracis. This novel method, CE universal tail mismatch amplification mutation assay (CUMA), allows for PCR multiplexing and automatic scoring of SNP genotypes, thus providing a rapid, economical and higher throughput alternative to more expensive SNP genotyping techniques. CUMA delivered accurate B. anthracis SNP genotyping results and, when multiplexed, saved reagent costs by more than 80% compared with TaqMan real‐time PCR. When real‐time PCR technology and instrumentation is unavailable or the reagents are cost‐prohibitive, CUMA is a powerful alternative for SNP genotyping.
Identification of an aggressive prostate cancer predisposing variant at 11q13
Authors: Nurminen Riikka , Wahlfors Tiina , Tammela Teuvo L. J. , Schleutker Johanna
Published: November 2010

Prostate cancer is the most frequently diagnosed cancer in men; however, the genetic basis of susceptibility remains elusive. The EMSY gene is located in the prostate cancer linked chromosome region at 11q13.5. The aim of this study was to screen EMSY for sequence variants and to evaluate its association with the risk of prostate cancer. We performed a Finnish population‐based case–control study with 923 controls, 184 familial prostate cancer cases and 2,301 unselected prostate cancer cases. Variants were screened using sequencing and validated using the TaqMan assay and High Resolution Melting analysis. A total of 27 sequence variants were found, and 17 of them were novel. A rare intronic variant, IVS6‐43A>G (minor allele frequency of 0.004), increased the prostate cancer risk in familial cases (odds ratio [OR] = 7.5; 95% confidence interval [CI] = 1.3–45.5; p = 0.02). Further analysis with clinicopathological data revealed that the variant is associated with aggressive unselected cases (prostate specific antigen ≥ 20 μg/L or Gleason grade ≥ 7), based on both case–control (OR = 6.0; 95% CI = 1.3–26.4; p = 0.03) and case–case analyses (OR = 6.5; 95% CI = 1.5–28.4; p = 0.002). In addition, all variant‐positive familial cases had aggressive cancer. Our results indicate that the intronic variant IVS6‐43A>G increases the familial and unselected prostate cancer risk in a Finnish population and contributes to the aggressive progression of the disease in a high‐penetrance manner. The potential role of the variant as a predictive genetic marker for aggressive prostate cancer should be further evaluated.
The prenylflavonoid phytoestrogens 8‐prenylnaringenin and isoxanthohumol diferentially suppress steroidogenesis in rat Leydig cells in ontogenesis
Authors: Izzo Gaia , Söder Olle , Svechnikov Konstantin
Published: November 2010

8‐Prenylnaringenin and isoxanthohumol are prenylflavonoids found in the hop plant, Humulus lupulus (Cannabaceae), which is traditionally used to add bitterness and flavor to beer. Flavonoids have previously been reported to exert endocrine disrupting actions. Therefore, we investigated the effects of 8‐prenylnaringenin and isoxanthohumol on steroidogenesis activated by human chorionic gonadotropin (hCG) in primary cultures of rat Leydig cells at different stages of their development. The present study is the first to demonstrate that the prenylflavonoids 8‐prenylnaringenin and isoxanthohumol exert complex maturation‐dependent effects on Leydig cell steroidogenesis. Those compounds inhibited hCG‐stimulated androgen production by Leydig cells at all stages of their development, a process that was associated with the reduced ability of the cells to produce cAMP. However, these same compounds up‐regulated hCG‐activated StAR expression in progenitor (PLC) and immature (ILC) but not adult types of Leydig cells (ALC). Further, 8‐prenylnaringenin and isoxanthohumol were not able to suppress androgen production activated by an exogenous analog of cAMP, (Bu)2cAMP, in ALC and ILC but synergistically stimulated steroidogenesis in PLC. Our data suggest that 8‐prenylnaringenin and isoxanthohumol affect cAMP‐dependent cellular processes up‐stream transport of cholesterol into mitochondria. Copyright © 2010 John Wiley & Sons, Ltd.
Co‐electrospun fibrous scaffold–adsorbed DNA for substrate‐mediated gene delivery
Authors: Zhang Jun , Duan Yajun , Wei Di , Wang Lianyong , Wang Hongjun , Gu Zhongwei , Kong Deling
Published: November 2010

Incorporation of gene into electrospun nanofibers for localized gene transfection of target cells represents a robust platform for tissue regeneration. In this study, a new two‐step approach was explored to immobilize DNA onto electrospun nanofibers for effective gene delivery, that is, nonviral gene vector of polyethylene glycol (PEG)‐modified polyethylenimine (PEI) was incorporated into scaffolds by electrospinning and then target DNA was adsorbed onto the electrospun nanofibers via electrostatic interaction between DNA and PEI–PEG. PEI–PEG/DNA particles formed from the released DNA, and PEI–PEG had a uniform particle size of approximately 200 nm. This nanofiber‐based gene delivery system exhibited high transfection efficiency, in which >65% of human embryonic kidney 293 cells and >40% of mesenchymal stem cells were transfected with green fluorescent protein gene. Compared with PEI, PEG modification of PEI had improved the biocompatibility and further increased the transfection efficiency. These results suggest that the combination of nonviral gene carrier with electrospun nanofibers could be used for localized gene delivery, which has multifold potential applications in tissue engineering or as anin vivosubstrate for tissue regeneration. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2010.
Assessing general side effects in clinical trials: reference data from the general population
Authors: Rief Winfried , Barsky Arthur J. , Glombiewski Julia A. , Nestoriuc Yvonne , Glaesmer Heide , Braehler Elmar
Published: November 2010

Purpose

Side effects in clinical trials are frequently assessed in an unstructured fashion, using ascertainment strategies with unclear quality criteria. To improve the assessment and interpretation of general side effects, a structured approach is presented and validated (General Assessment of Side Effects, GASE). Base rates and reference data of the general population as well as quality criteria of this new side effect ascertainment method are provided.

Methods

We developed a screener assessing the most common subjective side effects of clinical trials (according to FDA statistics and others). The screener was evaluated in a general population survey including 2512 participants, 1276 of them taking drugs.

Results

We present reference data of the general population that help to interpret and compare future results of clinical trials assessing general side effects. Highest scores for side effects were reported from users of psychopharmacological drugs, medium scores of people taking antihypertensives, and lower scores of people taking lipid‐lowering drugs, pain killers, and antidiabetics. If people take multiple drugs, more side effects are reported compared to single‐class drugs. This confirms GASE's validity to assess side effects.

Conclusion

We suggest that a structured, patient‐based approach to assess general side effects could improve the detection of drug‐induced side effects. The problem of clinical studies being underpowered to detect side effects could be reduced by using more reliable approaches. Our plea is for side effect ascertainment with sophisticated approaches for expected side effects, systematic screening for general side effects, and open question methods for spontaneous reports. Copyright © 2010 John Wiley & Sons, Ltd.
A DFT‐GIAO and DFT‐NBO study of polar substituent effects on NMR 17O chemical shifts in some rigid polycyclic alkanes
Authors: Adcock William
Published: November 2010

17O NMR shieldings of 3‐substituted(X)bicyclo[1.1.1]pentan‐1‐ols (1, Y = OH), 4‐substituted(X)bicyclo[2.2.2]octan‐1‐ols (2, Y = OH), 4‐substituted(X)‐bicyclo[2.2.1]heptan‐1‐ols (3, Y = OH), 4‐substituted(X)‐cuban‐1‐ols (4, Y = OH) and exo‐ and endo‐ 6‐substituted(X)exo‐bicyclo[2.2.1]heptan‐2‐ols (5 and 6, Y = OH, respectively), as well as their conjugate bases (1–6, Y = O−), for a set of substituents (X = H, NO2, CN, NC, CF3, COOH, F, Cl, OH, NH2, CH3, SiMe3, Li, O−, and NH) covering a wide range of electronic substituent effects were calculated using the DFT‐GIAO theoretical model at the B3LYP/6‐311 + G(2d, p) level of theory. By means of natural bond orbital (NBO) analysis various molecular parameters were obtained from the optimized geometries. Linear regression analysis was employed to explore the relationship between the calculated 17O SCS and polar field and group electronegativity substituent constants (σF and σχ, respectively) and also the NBO derived molecular parameters (oxygen natural charge, Qn, occupation numbers of the oxygen lone pairs, no, and occupancy of the CO antibonding orbital, σ*CO(occup)). In the case of the alcohols (1–6, Y = OH) the 17O SCS appear to be governed predominantly by the σχ effect of the substituent. Furthermore, the key determining NBO parameters appear to be no and σ*CO(occup). Unlike the alcohols, the calculated 17O SCS of the conjugate bases (1–6, Y = O−), except for system 1, do not respond systematically to the electronic effects of the substituents. An analysis of the SCS of 1(Y = O−) raises a significant conundrum with respect to their origin. Copyright © 2010 John Wiley & Sons, Ltd.
A method for rapid calculation of two‐exciton states
Authors: Ajiki Hiroshi
Published: November 2010

I propose a rapid‐calculation method of two‐exciton states in one‐dimensional tight‐binding model. An equation for energy levels of two‐exciton states is derived, in which energy regions including one solution are specified. Therefore, energy levels of two‐exciton states can be absolutely calculated by using the bisection method. The present method dramatically improves a computation time because neither diagonalization nor summation is needed. Wave functions of the two‐exciton states are also calculated immediately.
Electrostatic field control of exciton–plasmon coupling and optical response of individual carbon nanotubes
Authors: Bondarev I. V.
Published: November 2010

An electrostatic field applied perpendicular to the nanotube axis can control the coupling of excitonic states to interband surface plasmon modes in individual small‐diameter (∼1 nm) semiconducting single wall carbon nanotubes (CNs). This allows one to manipulate by the exciton emission from individual nanotubes, both in the linear excitation regime and in the non‐linear excitation regime with the photoinduced biexcitonic states formation. These results should be useful for the development of new tunable optoelectronic device applications of optically excited semiconducting CNs.

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