bluuebunny/crossref_metadata_2025 huggingface dataset:
External Donor Induced Direct Contact Effects on Mg(OC2H5)2‐Based Ziegler‐Natta Catalysts for Propylene Polymerization
Authors: Kim Sang Yull , Hiraoka Yuichi , Taniike Toshiaki , Terano Minoru
Published: November 2009

Effects of external donor induced direct contact without alkylaluminum were studied for Ziegler‐Natta catalysts containing monoester and diester as internal donors on the catalytic performances such as activity and stereoselectivity. Traditional slurry polymerizations were carried out for rather short period after direct contact for a variety of time. GC analysis was also performed to observe replacement phenomena of donors during direct contact. It was postulated that the different performances of the catalysts were greatly affected by the pair of internal and external donors.
Structural determination of abutilins A and B, new flavonoids from Abutilon pakistanicum, by 1D and 2D NMR spectroscopy
Authors: Ali Bakhat , Imran Muhammad , Hussain Riaz , Ahmed Zaheer , Malik Abdul
Published: November 2009

Two new flavonoids, abutilin A and B, were isolated from the chloroform soluble fraction of Abutilon pakistanicum and their structures assigned from 1H and 13C NMR spectra, DEPT and by 2D COSY, HMQC and HMBC experiments. Ferulic acid (3), (E)‐cinnamic acid (4), 5‐hydroxy‐4′,6,7,8‐tetramethoxyflavone (5), kaempferol (6), luteolin (7) and luteolin 7‐O‐β‐D‐glucopyranoside (8) have also been reported from this species. Copyright © 2009 John Wiley & Sons, Ltd.
Numerical integration of an elastic–viscoplastic constitutive model for dry metamorphosed snow
Authors: Cresseri Silene , Genna Francesco , Jommi Cristina
Published: November 2009

A constitutive model for dry metamorphosed snow is proposed, within the framework of elasto‐viscoplasticity, which is able to reproduce the most relevant features of the macroscopic behaviour of snow, particularly its time and rate dependency. The basic ideas for modelling stem from the conceptual forms proposed for bonded geomaterials, such as cemented soils or soft rocks. The high viscosity of snow is accounted for by adopting an overstress approach, suitably modified. An evolution law for the curvature‐driven process of sintering, by which intergranular ice necks form and grow, is established. The system of constitutive equations is then numerically integrated via a fully implicit time stepping scheme. Selected results from finite element simulations of laboratory tests, available in the literature, are presented. Copyright © 2009 John Wiley & Sons, Ltd.
On problems of differential diagnosis in palaeopathology, as illustrated by a case from prehistoric Indiana
Authors: Brothwell D.
Published: November 2009

Because palaeopathology has to call on a limited range of evidence, compared with modern clinical diagnosis, it is important that a differential diagnosis should be broad‐based. A prehistoric case from Indiana is discussed in relation to this statement. Copyright © 2009 John Wiley & Sons, Ltd.
Horse radish peroxidase immobilized polyaniline for hydrogen peroxide sensor
Authors: Solanki Pratima R. , Kaushik Ajeet , Ansari Anees A. , Sumana G. , Malhotra B. D.
Published: November 2009

Horse radish peroxidase (HRP) has been electrochemically entrapped into perchlorate (ClO) doped polyaniline (PANI) film deposited onto indium‐tin‐oxide (ITO) coated glass plate. This HRP‐PANI‐ClO/ITO bioelectrode characterized using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), UV‐Visible spectroscopy, cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS) techniques has been utilized for estimation of hydrogen peroxide (H2O2). This H2O2 sensor exhibits response time of 5 s, linearity from 3 to 136 mM, sensitivity as 0.5638 µA mM−1 cm−2 with linear regression of 0.985. The value of the Michaelis–Menten constant (Km) has been obtained as 1.984 mM. Copyright © 2009 John Wiley & Sons, Ltd.
Introduction to the special issue: Using prevention science to address mental health issues in schools
Authors: Stormont Melissa , Reinke Wendy M. , Herman Keith C.
Published: November 2009

This article provides a definition and history of prevention science, presents the contemporary definition of prevention, and outlines the prevention science research cycle. The work of scholars who have developed innovative methods and practices and/or who are leaders in their dissemination were invited in this special issue to discuss their work in relation to the prevention science framework. This introduction to the special issue, Using Prevention Science to Address the Mental Health Issues in Schools, highlights the need for prevention‐minded research in schools. © 2009 Wiley Periodicals, Inc.
Identification and characterization of novel ERC‐55 interacting proteins: Evidence for the existence of several ERC‐55 splicing variants; including the cytosolic ERC‐55‐C
Authors: Ludvigsen Maja , Jacobsen Christian , Maunsbach Arvid B. , Honoré Bent
Published: November 2009

ERC‐55, encoded fromRCN2, is localized in the ER and belongs to the CREC protein family. ERC‐55 is involved in various diseases and abnormal cell behavior, however, the function is not well defined and it has controversially been reported to interact with a cytosolic protein, the vitamin D receptor. We have used a number of proteomic techniques to further our functional understanding of ERC‐55. By affinity purification, we observed interaction with a large variety of proteins, including those secreted and localized outside of the secretory pathway, in the cytosol and also in various organelles. We confirm the existence of several ERC‐55 splicing variants including ERC‐55‐C localized in the cytosol in association with the cytoskeleton. Localization was verified by immunoelectron microscopy and sub‐cellular fractionation. Interaction of lactoferrin, S100P, calcyclin (S100A6), peroxiredoxin‐6, kininogen and lysozyme with ERC‐55 was further studiedin vitroby SPR experiments. Interaction of S100P requires [Ca2+] of ∼10−7 M or greater, while calcyclin interaction requires [Ca2+] of >10−5 M. Interaction with peroxiredoxin‐6 is independent of Ca2+. Co‐localization of lactoferrin, S100P and calcyclin with ERC‐55 in the perinuclear area was analyzed by fluorescence confocal microscopy. The functional variety of the interacting proteins indicates a broad spectrum of ERC‐55 activities such as immunity, redox homeostasis, cell cycle regulation and coagulation.
Laser‐Induced Deflagration of Unconfined HMX – The Effect of Energetic Binders
Authors: Ahmad Sheikh Rafi , Russell David Anthony , Golding Peter
Published: November 2009

The effect of three energetic binders [poly(3‐methyl‐3‐nitratomethyloxetane (polyNIMMO), polyglycidyl nitrate (polyGLYN) and an energetic polyphosphazene (PPZ‐E) – all at 10%] on the unconfined laser‐induced deflagration of cyclotetramethylene tetranitramine, commonly known as High Melting point Explosive (HMX) by a near IR (NIR) diode laser (801 nm) has been examined. Hydroxyl terminated polybutadiene (HTPB) and PPZ (the precursor to PPZ‐E – before nitration) were used as reference materials. The formulations required the addition of an optical sensitizer – carbon black (CB) – for ignition. At the designated threshold flux density of 2.3 kW cm−2, a minimum of ∼1 wt.‐% CB was needed for the reliable ignition of unbound HMX and its formulations with polyGLYN, PPZ‐E and PPZ. Under similar conditions HMX/polyNIMMO and HMX/HTPB required 3% CB. Ignition maps (ignition time versus laser flux density) have been constructed for the five formulations. Comparison of ignition times and ignition energy densities for HMX and HMX/polyGLYN showed this binder to have only a marginal effect. In contrast, HTPB, PPZ and PPZ‐E all retarded HMX ignition at the threshold flux density, but showed negligible effect at higher flux densities. As PPZ and PPZ‐E produced both similar delays in the ignition time and similar increases in the flame development times (10–90%) at the threshold flux density, the inhibition of the HMX ignition by these PPZs appears to be largely independent of the polymer energy content. Such characteristics could be useful for high performance and insensitive energetic formulations. PolyNIMMO (3% CB) increased the ignition time of HMX only slightly at 2.3 kW cm−2. However, at this threshold flux level the HMX flame development times with polyNIMMO or HTPB were much longer than that for the unbound material; this effect is attributed to the enhanced CB content.
A galaxy of folds
Authors: Alva Vikram , Remmert Michael , Biegert Andreas , Lupas Andrei N. , Söding Johannes
Published: November 2009

Many protein classification systems capture homologous relationships by grouping domains into families and superfamilies on the basis of sequence similarity. Superfamilies with similar 3D structures are further grouped into folds. In the absence of discernable sequence similarity, these structural similarities were long thought to have originated independently, by convergent evolution. However, the growth of databases and advances in sequence comparison methods have led to the discovery of many distant evolutionary relationships that transcend the boundaries of superfamilies and folds. To investigate the contributions of convergent versus divergent evolution in the origin of protein folds, we clustered representative domains of known structure by their sequence similarity, treating them as point masses in a virtual 2D space which attract or repel each other depending on their pairwise sequence similarities. As expected, families in the same superfamily form tight clusters. But often, superfamilies of the same fold are linked with each other, suggesting that the entire fold evolved from an ancient prototype. Strikingly, some links connect superfamilies with different folds. They arise from modular peptide fragments of between 20 and 40 residues that co‐occur in the connected folds in disparate structural contexts. These may be descendants of an ancestral pool of peptide modules that evolved as cofactors in the RNA world and from which the first folded proteins arose by amplification and recombination. Our galaxy of folds summarizes, in a single image, most known and many yet undescribed homologous relationships between protein superfamilies, providing new insights into the evolution of protein domains.
An assessment of a Greenland lee cyclone during the Greenland Flow Distortion experiment: An observational approach
Authors: Mc Innes Harold , Kristjánsson Jón Egill , Schyberg Harald , Røsting Bjørn
Published: November 2009

On 3 March 2007 between 0920 and 1545 UTC, the mesoscale structure of a mature lee cyclone southeast of Greenland was successfully captured during a flight with a research aircraft during the Greenland Flow Distortion experiment (GFDex). The cyclone was accompanied by hazardous weather conditions such as extensive icing and low‐level wind speeds exceeding 34 m s−1. Calculations based on atmospheric soundings from Egedesminde on the west coast of Greenland indicate that conditions were favourable for flow splitting and hence cyclogenesis in the lee of Greenland during the formation of the cyclone. PV inversion carried out on an upper‐level southward‐moving potential vorticity (PV) anomaly indicates that upper‐level forcing as well as orographic forcing had an important role in the cyclone development. The frontal seclusion of the cyclone's warm core was consistent with both the Norwegian cyclone model and Shapiro and Keyser's model. However, it was not possible to match this cyclone precisely with any of these models, which is probably a consequence of the strong influence from Greenland on the cyclone development. In situ measurements showing a combination of warm dry air with relatively high ozone concentrations in the centre of the cyclone together with trajectory calculations indicate that this air had experienced considerable descent, probably induced by Greenland's orography. The observations documented the cyclone's mesoscale structure, and clearly revealed a deep tropopause fold. This tropopause fold is a manifestation of the forcing on the cyclone from the upper‐level PV anomaly. Copyright © 2009 Royal Meteorological Society
Sterilization Matters: Consequences of Different Sterilization Techniques on Gold Nanoparticles
Authors: França Ángela , Pelaz Beatriz , Moros María , Sánchez‐Espinel Christian , Hernández Andrea , Fernández‐López Cristina , Grazú Valeria , de la Fuente Jesús M. , Pastoriza‐Santos Isabel , Liz‐Marzán Luis M. , González‐Fernández África
Published: November 2009

Nanoparticles (NPs) can offer many advantages over traditional drug design and delivery, as well as toward medical diagnostics. As with any medical device or pharmaceutical drug intended to be used for in vivo biomedical applications, NPs must be sterile. However, very little is known regarding the effect of sterilization methods on the intrinsic properties and stability of NPs. Herein a detailed analysis of physicochemical properties of two types of AuNPs upon sterilization by means of five different techniques is reported. In addition, cell viability and production of reactive oxygen species are studied. The results indicate that sterilization by ethylene oxide seems to be the most appropriate technique for both types of NPs. It is concluded that it is crucial to test several methods in order to establish the specific type of sterilization to be performed for each particular NP.
The application of flux balance analysis in systems biology
Authors: Gianchandani Erwin P. , Chavali Arvind K. , Papin Jason A.
Published: November 2009

An increasing number of genome‐scale reconstructions of intracellular biochemical networks are being generated. Coupled with these stoichiometric models, several systems‐based approaches for probing these reconstructions in silico have been developed. One such approach, called flux balance analysis (FBA), has been effective at predicting systemic phenotypes in the form of fluxes through a reaction network. FBA employs a linear programming (LP) strategy to generate a flux distribution that is optimized toward a particular ‘objective,’ subject to a set of underlying physicochemical and thermodynamic constraints. Although classical FBA assumes steady‐state conditions, several extensions have been proposed in recent years to constrain the allowable flux distributions and enable characterization of dynamic profiles even with minimal kinetic information. Furthermore, FBA coupled with techniques for measuring fluxes in vivo has facilitated integration of computational and experimental approaches, and is allowing pursuit of rational hypothesis‐driven research. Ultimately, as we will describe in this review, studying intracellular reaction fluxes allows us to understand network structure and function and has broad applications ranging from metabolic engineering to drug discovery. Copyright © 2009 John Wiley & Sons, Inc.

This article is categorized under:

Analytical and Computational Methods > Computational Methods
One hundred seven consecutive surgical resections for hilar cholangiocarcinoma of Bismuth types II, III, IV between 2001 and 2008
Authors: Miyazaki Masaru , Kimura Fumio , Shimizu Hiroaki , Yoshidome Hiroyuki , Otuka Masayuki , Kato Atushi , Yoshitomi Hideyuki , Furukawa Katsunori , Takeuchi Dan , Takayashiki Tsukasa , Suda Kousuke , Takano Shigetugu
Published: November 2009

Many authors at high‐volume centers all over the world have reported improved outcomes of hilar cholangiocarcinoma by several aggressive surgical approaches such as extended hepatic resection, combined vascular resection, and hepatopancreaticoduodenectomy in recent years. There has been great progress in the surgical treatment of hilar cholangiocarcinoma with these previous efforts by aggressive hepatobiliary surgeons. In particular, surgical techniques, diagnostic modalities, and perioperative management have been remarkably improved as compared with before. Herein we report the surgical outcome for both hilar cholangiocarcinoma of Bismuth types II, III, and IV and intrahepatic cholangiocarcinoma involving the hepatic duct confluence during the recent 8‐year period between 2001 and 2008 at our institution, the Department of General Surgery at Chiba University. From our recent experienced results, it can be concluded that the surgical strategy for hilar cholangiocarcinoma has been improved remarkably, and major surgical hepatectomy can be done with relative safety, and these aggressive surgical approaches, including combined vascular resection, may be warranted for the surgical treatment of hilar cholangiocarcinoma. However, the adoption of new innovative therapeutic approaches might be required for further improvement of surgical outcome of hilar cholangiocarcinoma.
Infant head growth in male siblings of children with and without autism spectrum disorders
Authors: Constantino John N. , Majmudar Palak , Bottini Alex , Arvin Molly , Virkud Yamini , Simons Paul , Spitznagel Edward L.
Published: November 2009

Previous research has indicated that children with autism exhibit accelerated head growth (HG) in infancy, although the timing of acceleration varies between studies. We examined infant HG trajectory as a candidate autism endophenotype by studying sibling pairs. We retrospectively obtained serial head orbitofrontal circumference measurements of: a) 48 sibling pairs in which one (n = 28) or both (n = 20) sibs were affected by an autism spectrum disorder (ASD); and b) 85 control male sibling pairs. Rate of HG of ASD subjects was slightly accelerated compared to controls, but the magnitude of difference was below the limit of reliability of standard measurement methods. Sibling intra class correlation for rate of HG was highly statistically significant; the magnitude was significantly stronger among autism-affected families (ICC = .63) than among controls (ICC = .26), p < .01. Infant HG trajectory appears familial—possibly endophenotypic—but was not a reliable marker of autism risk among siblings of ASD probands in this sample.
Do all modifications benefit all tRNAs?
Authors: Phizicky Eric M. , Alfonzo Juan D.
Published: November 2009

Despite the universality of tRNA modifications, some tRNAs lacking specific modifications are subject to degradation pathways, while other tRNAs lacking the same modifications are resistant. Here, we suggest a model in which some modifications have minor, possibly redundant, roles in specific tRNAs. This model is consistent with the low specificity of some modification enzymes. Limitations of this model include the limited assays and growth conditions on which these conclusions are based, as well as the high specificity exhibited by many modification enzymes with important roles in translation. The specificity of these enzymes is often enhanced by complex substrate recognition patterns and sub‐cellular compartmentalization.
Cellular dynamics of tRNAs and their genes
Authors: Hopper Anita K. , Pai Dave A. , Engelke David R.
Published: November 2009

This discussion focuses on the cellular dynamics of tRNA transcription, processing, and turnover. Early tRNA biosynthesis steps are shared among most tRNAs, while later ones are often individualized for specific tRNAs. In yeast, tRNA transcription and early processing occur coordinately in the nucleolus, requiring topological arrangement of ∼300 tRNA genes and early processing enzymes to this site; later processing events occur in the nucleoplasm or cytoplasm. tRNA nuclear export requires multiple exporters which function in parallel and the export process is coupled with other cellular events. Nuclear‐cytoplasmic tRNA subcellular movement is not unidirectional as a retrograde pathway delivers mature cytoplasmic tRNAs to the nucleus. Despite the long half‐lives, there are multiple pathways to turnover damaged tRNAs or normal tRNAs upon cellular stress.
Contingency relationships of firm size, TQM duration, unionization, and industry context on TQM implementation—A focus on total effects
Authors: Jayaram Jayanth , Ahire Sanjay L. , Dreyfus Paul
Published: November 2009

Past TQM literature has been inconclusive in resolving the validity of the universalistic approach versus the contingency approach of TQM implementation. In this paper we contribute to the resolution of this debate by using a total effects approach within the contingency perspective. We propose a culture‐quality system design‐outcomes framework for TQM implementation. We then use this framework to study the differences in total effects relationships among TQM constructs across four contingencies, firm size, TQM duration, unionization, and industry type. Data from a sample of 394 plants (SIC codes 20 through 39) are used to test the validity of our contingency model. Our results revealed that firm size, TQM duration, and industry type moderate the influence of total effects of culture (top management commitment, customer focus, and trust) on final outcomes (process quality, product quality, and customer satisfaction). These contingencies also moderate the influence of total effects of quality system design (design management, training, empowerment, quality information usage, supplier quality management, and process quality management) on final outcomes. The strongest contributor to variation in total effects across groups was industry type, followed by size and then TQM duration. To a lesser extent, unionization was a moderator in total effects relationships. These findings uniquely contribute to the emerging contingency theory of TQM implementation.
Opportunities for improving irrigation efficiency with quantitative models, soil water sensors and wireless technology
Authors: GREENWOOD D. J. , ZHANG K. , HILTON H. W. , THOMPSON A. J.
Published: November 2009

Increasingly serious shortages of water make it imperative to improve the efficiency of irrigation in agriculture, horticulture and in the maintenance of urban landscapes. The main aim of the current review is to identify ways of meeting this objective. After reviewing current irrigation practices, discussion is centred on the sensitivity of crops to water deficit, the finding that growth of many crops is unaffected by considerable lowering of soil water content and, on this basis, the creation of improved means of irrigation scheduling. Subsequently, attention is focused on irrigation problems associated with spatial variability in soil water and the often slow infiltration of water into soil, especially the subsoil. As monitoring of soil water is important for estimating irrigation requirements, the attributes of the two main types of soil water sensors and their most appropriate uses are described. Attention is also drawn to the contribution of wireless technology to the transmission of sensor outputs. Rapid progress is being made in transmitting sensor data, obtained from different depths down the soil profile across irrigated areas, to a PC that processes the data and on this basis automatically commands irrigation equipment to deliver amounts of water, according to need, across the field. To help interpret sensor outputs, and for many other reasons, principles of water processes in the soil–plant system are incorporated into simulation models that are calibrated and tested in field experiments. Finally, it is emphasized that the relative importance of the factors discussed in this review to any particular situation varies enormously.
Cultural Preferences and Economic Constraints: The Living Arrangements of Elderly Canadians
Authors: Kaida Lisa , Moyser Melissa , Park Stella Y.
Published: November 2009

Utilisant les donnés du recensement canadien de 2001, nous examinons le rôle des préférences culturelles et des contraintes économiques sur la situation domestique des personnes âgées (vivre avec son enfant et/ou une personne apparentée versus vivre de façon autonome). Nos analyses révèlent que les membres de groupes ethniques partageant des valeurs familialistes (italien, chinois, sud-asiatique, et indien d’Asie) sont plus susceptibles que leur homologues individualistes (britannique, allemand, et néerlandais) de vivre avec un proche parent. Toutefois, l’importance des préférences culturelles et des contraintes économiques dépendent en grande partie de l’état matrimonial. Pour les personnes mariées, les préférences culturelles expliquent une grande proportion de la variation des situations domestiques. Pour ce qui est des personnes célibataires, les contraintes économiques sont plus importantes. En comparaison avec les études antérieures, où celles-ci négligent le rôle de l’état matrimonial, cette recherche contribue à une compréhension plus nuancée de la situation domestique des personnes âgées.
Pandemic (H1N1) 2009 virus outbreak in a school in London, April–May 2009: an observational study
Authors: CALATAYUD L. , KURKELA S. , NEAVE P. E. , BROCK A. , PERKINS S. , ZUCKERMAN M. , SUDHANVA M. , BERMINGHAM A. , ELLIS J. , PEBODY R. , CATCHPOLE M. , HEATHCOCK R. , MAGUIRE H.
Published: November 2009

On 29 April 2009, an imported case of pandemic (H1N1) 2009 virus infection was detected in a London school. As further cases, pupils and staff members were identified, school closure and mass prophylaxis were implemented. An observational descriptive study was conducted to provide an insight into the clinical presentation and transmission dynamics in this setting. Between 15 April and 15 May 2009, 91 symptomatic cases were identified: 33 were confirmed positive for pandemic (H1N1) 2009 virus infection; 57 were tested negative; in one the results were unavailable. Transmission occurred first within the school, and subsequently outside. Attack rates were 2% in pupils (15% in the 11–12 years age group) and 17% in household contacts. The predominant symptoms were fever (97%), respiratory symptoms (91%), and sore throat (79%). Limited spread in the school may have been due to a combination of school closure and mass prophylaxis. However, transmission continued through household contacts to other schools.
Ocean acidification reduces sperm flagellar motility in broadcast spawning reef invertebrates
Authors: Morita Masaya , Suwa Ryota , Iguchi Akira , Nakamura Masako , Shimada Kazuaki , Sakai Kazuhiko , Suzuki Atsushi
Published: November 2009

Ocean acidification is now recognized as a threat to marine ecosystems; however, the effect of ocean acidification on fertilization in marine organisms is still largely unknown. In this study, we focused on sperm flagellar motility in broadcast spawning reef invertebrates (a coral and a sea cucumber). Below pH 7.7, the pH predicted to occur within the next 100 years, sperm flagellar motility was seriously impaired in these organisms. Considering that sperm flagellar motility is indispensable for transporting the paternal haploid genome for fertilization, fertilization taking place in seawater may decline in the not too distant future. Urgent surveys are necessary for a better understanding of the physiological consequences of ocean acidification on sperm flagellar motility in a wide range of marine invertebrates.
Definición de razas en llamas y alpacas
Authors: Renieri C. , Frank E.N. , Rosati A.Y. , Antonini M.
Published: November 2009

La raza representa un concepto central de la zootecnia y se usa para definir cualquier subdivisión dentro de una especie doméstica. En este trabajo se analiza el nacimiento y la evolución del concepto de raza a lo largo del tiempo y el impacto de la ciencia originada en su entorno. Se discuten los efectos de la domesticación desde un punto de vista genético y se clasifican las razas como: mendelianas, primarias, secundarias y sintéticas. Se analiza el concepto dentro de los camélidos domésticos y se llega a la conclusión que solo existen razas primarias. Se aclaran también conceptos desvirtuados sobre la alpaca Suri, las llamas-alpacas blancas y el concepto de pureza. Se concluye finalmente que se debería seguir el esfuerzo de empresas privadas y organizaciones publicas y privadas para organizar y establecer acciones de seleccion por llegar a la creación de razas estandarizadas.
Leicester Longwool sheep in the United States: saving an international rarity
Authors: Sponenberg D.P. , Henry J. , Smith-Anderson K. , Shirley E.
Published: November 2009

Leicester Longwool sheep are pivotal in the history of standardised sheep breeds. The breed was imported into the United States in 1990, and it was never imagined as more than a minor sideline to the array of breeds in the United States. Eighteen sheep were originally imported from Tasmania, with further contributions via semen from 12 rams in Australia, New Zealand, and the United Kingdom. In subsequent years the population of this breed in those source countries has plummeted, leaving the United States with the largest national flock (800). The decline in numbers worldwide have made the genetic management of the North American population increasingly important. The wool is sought by handcrafters and brings a premium price. Attention to maintaining the breed with its original fleece characteristics is an important priority, especially given the breed's role in the development of multiple longwool breeds. One divergence of the American flock from the other countries is the registration of coloured animals, and these make up 6% of the current flock.
The Six Cycles Maintenance Model: Growing a “Vicious Flower” for Depression
Authors: Moorey Stirling
Published: November 2009

Background:Cognitive behavioural models of anxiety disorders often include visual representations of feedback loops that maintain the disorder. Cognitive therapy for depression is the prototype for therapy for many other disorders, and there is now good evidence for factors that maintain depression, yet there is still no accepted diagrammatic form of the maintenance model.Aims:To develop a simple, clinically acceptable and empirically based version of the “vicious flower” for depression.Method:Current theoretical developments in depression (Differential activation and Beck's concept of modes) and empirical findings on maintenance factors were reviewed. A model was developed based on clinical utility and current knowledge of the processes and maintenance factors in depression. This model was tested for its usefulness with a small sample of IAPT trainees.Results:The model contained 6 cycles comprising 2 cognitive cycles (automatic negative thinking and rumination/self-attacking), 2 behavioural cycles (withdrawal/avoidance and unhelpful behaviour), a mood/emotion cycle, and a motivation/physical symptoms cycle. Students found it a very useful tool for understanding maintenance factors.Conclusions:This diagrammatic maintenance model of depression, like similar “vicious flowers” for anxiety, may be helpful in conceptualization, socialization and treatment planning as well as teaching CBT.
Evidence for biodegradation products in the interstellar medium
Authors: Rauf Kani , Wickramasinghe Chandra
Published: November 2009

The interstellar absorption band centred on 2175 Å that is conventionally attributed to monodisperse graphite spheres of radii 0.02 μm is more plausibly explained as arising from biologically derived aromatic molecules. On the basis of panspermia models, interstellar dust includes a substantial fraction of biomaterial in various stages of degradation. We have modeled such an ensemble of degraded biomaterial with laboratory spectroscopy of algae, grass pigments, bituminous coal and anthracite. The average ulrtraviolet absorption profile for these materials is centred at 2175 Å with a full width at half maximum of 250 Å, in precise agreement with the interstellar extinction observations. Mid-infrared spectra also display general concordance with the unidentified interstellar absorption features found in a wide variety of astronomoical sources.
Genetic diversity and phaseolin variation in Portuguese common bean landraces
Authors: Igrejas G. , Carnide V. , Pereira P. , Mesquita F. , Guedes-Pinto H.
Published: November 2009

A collection of 18 landraces of common bean (Phaseolus vulgarisL.) from northern Portugal was evaluated for both phaseolin pattern and a set of qualitative and quantitative traits. The phaseolin Contender and Tendergreen types were the most commonly occurring, with Boyaca and Huevo de Huanchaco present, but rare. The colour of the flower standard and wing, and seed shape, colour and size were all highly variable. On the basis of morphological traits, the landraces and testers clustered into two main groups. No relationship was found between phaseolin profile and any of the quantitative traits measured. Based on phaseolin patterns, the origin of Portuguese common bean populations was probably the Andean region of South America.
Evaluation of the grain methionine, lysine and tryptophan contents of maize ( Zea mays L.) germplasm in the Germplasm Enhancement of Maize Project
Authors: Paul Scott M. , Blanco Michael
Published: November 2009

The Germplasm Enhancement of Maize (GEM) Project is a cooperative effort between the USDA-ARS, private industry and public researchers to broaden and enhance the germplasm base of maize. In this program, selected accessions from the Latin American Maize Project, and seven tropical hybrids donated by DeKalb to the GEM Project, were crossed to elite proprietary inbred lines contributed by commercial plant breeding programs. In most cases, the resulting hybrids were crossed to a second commercial inbred line and the resulting 25% exotic hybrids were used as breeding populations for further development. To identify GEM germplasm with value to protein quality breeding programs, we developed a process for evaluating the content of the essential amino acids methionine, lysine and tryptophan in the grain of GEM germplasm that balances the need for multiple-year evaluations with the constantly changing entry list of this germplasm screening program. This process involves annual field trials with common checks. Weak entries are dropped from the trial each year to make room for new entries, while strong entries are retained. Methionine exhibited the most significant variation, followed by lysine and then tryptophan. A number of GEM lines had methionine or lysine levels that were significantly better than Corn Belt checks and some were competitive with high-amino acid checks.
Hexacosanoic acid and other very long-chain fatty acids in peanut seed oil
Authors: Dean Lisa L. , Sanders Timothy H.
Published: November 2009

The fatty acid composition of peanut seed oil from a range of samples included in the core of the core or the ‘mini core’ of the US peanut germplasm collection was determined using gas chromatography. Oil contents of the seeds ranged from 31.4 to 47.9%. Very long-chain fatty acids are defined as those having more than 22 carbons in chain length. Although it has been reported in peanuts seed previously, the presence of hexacosanoic acid (C26:0) was quantified in a large variety of samples here for the first time along with docosanoic (C22:0) and tetracosanoic acids (C24:0) to demonstrate the potential of peanut seed as a source of very long-chain fatty acids that have been associated with widely varying effects such as the metabolism of the dietary fatty acids and physical properties of the oils themselves. Use of representative samples from the peanut germplasm collection allowed for comparison of very long-chain fatty acid content among seeds of different origins, and showed, although values overlapped, the seeds did cluster according to area of origin.
A case for in vivo mass‐independent fractionation of mercury isotopes in fish
Authors: Das Reshmi , Salters Vincent J. M. , Odom A. Leroy
Published: November 2009

The recent discovery of mass‐independent fractionation of mercury isotopes allows new constraints to be placed on the mercury cycle. Here we report new Hg isotopic analyses of zooplankton and fish from different trophic levels of a freshwater lake (Lake Jackson, Florida) bearing systematic mass‐independent fractionation of mercury isotopes. Fish muscle tissues show a progressive enrichment in the odd‐mass mercury isotopes having odd atomic mass numbers (199 and 201) with increasing trophic level. Trophic level was determined based on nitrogen isotopic composition as well as fish stomach content. Zooplankton in the lake contain mercury with Δ199Hg and Δ201Hg values of +0.43 (±0.07)‰ and +0.44 (±0.07)‰, respectively. The Δ199Hg values increase by ∼1‰ from ∼+0.4‰ in zooplankton, juvenile bluegill, and several other small fishes to Δ199Hg = +1.36‰ for the Florida gar, which is the top predator fish in the lake. Previous observations of odd‐mass‐number isotope enrichment of mercury have been explained by photoreduction and demethylation of methyl mercury in the water column or as isotope effects related to microbial methylation. However, our data and the data of Jackson et al. (2008) are also consistent with in vivo production of mass‐independent fractionation. Considering the alternatives, mass‐independent fractionation by metabolic processes is the most straightforward explanation for the mercury isotope data. There are two known mechanisms for mass‐independent fractionation of mercury, i.e., the nuclear volume effect and the magnetic isotope effect. While the data are insufficient to serve as proof, the magnitude of the mass‐independent effect and the nearly equal enrichment of 199Hg and 201Hg seem most suggestive of a magnetic isotope effect.
Influences of seasonal flow regime on the fate and transport of fine particles and a dissolved solute in a New England stream
Authors: Karwan Diana L. , Saiers James E.
Published: November 2009

Fine particles are necessary for biogeochemical cycling but pose a risk to water quality if they are present in excess or carry sorbed contaminants. The objective of this work is to elucidate the effects of flow on the transport and retention of fine particles within a mountain stream and to compare particulate matter transport processes to those of a conservative solute tracer. We measured the migration of bromide (a conservative solute tracer) and micrometer‐sized titanium‐dioxide particles under three seasonal flow regimes in second‐order stream in Connecticut. A one‐dimensional transport model based upon the transient storage model was applied in inverse mode to the measured data to quantify solute and particle transport processes. Rates of particle movement by advection and longitudinal dispersion matched those of bromide. Transient, or temporary, storage influenced conservative solute transport, while particle storage was irreversible on the time scale of our experiments and likely dominated by deposition within the sediments of the hyporheic zone. Both solute transient storage and particle deposition increased with decreasing discharge.
Effects of Lifestyle Changes to Reduce Risks of Diabetes and Associated Cardiovascular Risks: Results from Large Scale Efficacy Trials
Authors: Horton Edward S.
Published: November 2009

The increasing prevalence of type 2 diabetes throughout the world is now recognized as a major health problem. A growing segment of the population has impaired glucose tolerance (IGT), which is a strong predictor of progression to type 2 diabetes. Further, 24% of Americans now meet the criteria for the metabolic syndrome, a risk factor for both type 2 diabetes and cardiovascular disease (CVD). The diabetes epidemic is associated with changes in lifestyle—most notably increased energy intake, changes in diet composition and decreased levels of physical activity—and the development of overweight and obesity. This review examines the effects of several intensive lifestyle intervention trials on the risk of diabetes and CVD among high‐risk populations. Common features of these lifestyle interventions are dietary modification, weight loss and increased physical activity. These trials indicate that lifestyle modification is effective in decreasing the progression from IGT to type 2 diabetes and reducing CVD risk factors. However, the effectiveness of lifestyle interventions for reductions in CVD events has yet to be determined.
Excitation dynamics in polymer-coated semiconductor quantum dots with integrated dye molecules: The role of reabsorption
Authors: Niebling Tobias , Zhang Feng , Ali Zulqurnain , Parak Wolfgang J. , Heimbrodt Wolfram
Published: November 2009

Inorganic CdSe/ZnS core-shell quantum dots have been coated with amphiphilic polymers in order to enable their transfer to aqueous solutions. Additionally, ATTO-dye molecules have been embedded in the polymer shell. In this geometry ATTO dye acts as acceptor of the quantum dot donors' excitation. The energy transfer dynamics has been investigated in detail within the system by steady state and time-resolved optical spectroscopy. Radiative and nonradiative transfer processes dominate the photoluminescence properties of the quantum dots and dye molecules. Choosing different sizes of the quantum dots allowed for tuning the spectral overlap between the semiconductor dot emission and dye absorption. The experimental results have been described within a kinetic model which enables precisely to reveal the respective contributions of reabsorption and radiationless transfer rates. The distance dependence of quantum efficiencies and transfer rates shows that radiationless transfer is the more dominating the smaller the distance between the core of the nanoparticles and the dye molecules.
Effect of azimuthally asymmetric reactor components on a parallel plate capacitively coupled plasma
Authors: Kenney Jason A. , Rauf Shahid , Collins Ken
Published: November 2009

A three-dimensional fluid plasma model is used to investigate the impact of azimuthally asymmetric reactor components on spatial characteristics of parallel plate capacitively coupled plasmas. We consider three scenarios: high frequency (13.56 MHz) argon discharges with, separately, an off-axis circular plate surrounding the bottom electrode and an access port opening in the reactor sidewall, and a very high frequency (162 MHz) argon discharge with nonparallel electrodes. For the reactor with off-axis plate, both the Ar+ density and flux are strongly perturbed toward the direction of maximum grounded surface area, with azimuthal variation in ion flux up to 10%. Perturbations in Ar+ density due to the access port opening are localized to the region near the access port, and the impact on ion flux in the interelectrode region is minimal. Finally, the nonparallel electrodes result in a significant change in the location and shape of the Ar+ density profile, going from a center-peaked discharge with parallel electrodes to a flattened off-center profile when tilted less than 1° with a nominal 5 cm gap.
Adjustable resonance frequency and linewidth by Zr doping in Co thin films
Authors: Jiang Changjun , Xue Desheng , Guo Dangwei , Fan Xiaolong
Published: November 2009

Co 100 − x Zr x (40 nm) thin films with different Zr compositions were grown on silicon substrates by radio frequency magnetron sputtering. The coercivity decreased with an increase in the Zr composition. A uniaxial anisotropy existed in the Co100−xZrx films, and the anisotropy field of the films decreased from 55 to 40 Oe with the increase of Zr composition. The resonance frequency and linewidth were decreased with the increase of the Zr composition during the permeability measurements. For samples with x=0 and 9, the magnetic anisotropy effective field and saturated field were obtained by fitting the external magnetic field dependent resonance frequency with Landau–Lifschitz–Gilbert equation. Therefore, it is an effective way to get the adjustable anisotropy field and linewidth, which is desirable for obtaining the high resonance and high permeability ferromagnetic film materials for high frequency application.
Electrohydrodynamic repulsion of droplets falling on an insulating substrate in an electric field
Authors: Kim Bumjoo , Kim Intae , Joo Sang W. , Lim Geunbae
Published: November 2009

Control technique for charged droplets, named as electrohydrodynamic droplet repulsion (EDR), is reported. Charged droplets emitting from a capillary and falling down toward an insulating substrate are deflected from their intended impact point due to the like polarity of previously fallen droplets. The mechanism for this potentially critical phenomenon is explained by applying a theoretical model describing the balance between gravitational and Coulomb forces acting on a droplet. The parametric conditions for the EDR are subsequently presented.
Hard x-ray phase contrast imaging of black lipid membranes
Authors: Beerlink A. , Mell M. , Tolkiehn M. , Salditt T.
Published: November 2009

We report hard x-ray phase contrast imaging of black lipid membranes, freely suspended over a micromachined aperture in an aqueous solution. Biomolecular and organic substances can thus be probed in hydrated environments by parallel beam propagation imaging, using coherent multi-kilo-electronvolt x-ray radiation. The width of the thinning film can be resolved from analysis of the intensity fringes in the Fresnel diffraction regime down to about 200 nm. The thinning process, in which solvent is expelled from the space in between two opposing monolayers, is monitored, and the domain walls between coexisting domains of swollen and thinned membrane patches are characterized.
Stochastic bimodalities in deterministically monostable reversible chemical networks due to network topology reduction
Authors: Artyomov Maxim N. , Mathur Manikandan , Samoilov Michael S. , Chakraborty Arup K.
Published: November 2009

Recently, stochastic simulations of networks of chemical reactions have shown distributions of steady states that are inconsistent with the steady state solutions of the corresponding deterministic ordinary differential equations. One such class of systems is comprised of networks that have irreversible reactions, and the origin of the anomalous behavior in these cases is understood to be due to the existence of absorbing states. More puzzling is the report of such anomalies in reaction networks without irreversible reactions. One such biologically important example is the futile cycle. Here we show that, in these systems, nonclassical behavior can originate from a stochastic elimination of all the molecules of a key species. This leads to a reduction in the topology of the network and the sampling of steady states corresponding to a truncated network. Surprisingly, we find that, in spite of the purely discrete character of the topology reduction mechanism revealed by “exact” numerical solutions of the master equations, this phenomenon is reproduced by the corresponding Fokker–Planck equations.
Swelling and collapse of polyelectrolyte gels in equilibrium with monovalent and divalent electrolyte solutions
Authors: Yin De-Wei , Olvera de la Cruz Monica , de Pablo Juan J.
Published: November 2009

The swelling of polyelectrolyte (PE) gels by 1:1 and 2:1 salts is studied via osmotic ensemble Monte Carlo simulations at constant osmotic pressure and electrolyte chemical potential of a reservoir phase in equilibrium with a model PE network. Large molecular weight gels exhibit a remarkable swelling response to small changes in 2:1 salt concentration. Gel collapse is accompanied by the formation of a previously unknown heterogeneous nanostructure, predicted by theory and observed in simulations, consisting of regions dense in monomers coexisting with regions rich in mono- and divalent ions.
Localized soft modes and the supercooled liquid’s irreversible passage through its configuration space
Authors: Widmer-Cooper Asaph , Perry Heidi , Harrowell Peter , Reichman David R.
Published: November 2009

Using computer simulations, we show that the localized low frequency normal modes of a configuration in a supercooled liquid are strongly correlated with the irreversible structural reorganization of the particles within that configuration. Establishing this correlation constitutes the identification of the aspect of a configuration that determines the heterogeneity of the subsequent motion. We demonstrate that the spatial distribution of the summation over the soft local modes can persist in spite of particle reorganization that produces significant changes in individual modes. Along with spatial localization, the persistent influence of soft modes in particle relaxation results in anisotropy in the displacements of mobile particles over the time scale referred to as β-relaxation.