bluuebunny/crossref_metadata_2025 huggingface dataset:
From Natural Catastrophe to the Human Catastrophe: Plato on the Origins of Written Law
Authors: Cusher Brent Edwin
Published: September 2011

This article interprets the Athenian Stranger’s story of the origins of written law from Book III of Plato’s Laws, to the end of filling out the picture we have of Plato’s views on the purposes of law. The Athenian argues that the origins of written law reside exclusively in the need to address the problem of violent conflict among men resulting from dangerous passions and the scarcity of resources. While recent scholarship on Plato has focused on the promotion of virtue as the highest objective of law, this article clarifies the lower, but immediate and enduring, aspects of Plato’s jurisprudence.
Etv2/ER71 induces vascular mesoderm from Flk1+PDGFRα+ primitive mesoderm
Authors: Kataoka Hiroshi , Hayashi Misato , Nakagawa Reiko , Tanaka Yosuke , Izumi Naoki , Nishikawa Satomi , Jakt Martin Lars , Tarui Hiroshi , Nishikawa Shin-Ichi
Published: September 2011

Etv2 (Ets Variant 2) has been shown to be an indispensable gene for the development of hematopoietic cells (HPCs)/endothelial cells (ECs). However, how Etv2 specifies the mesoderm-generating HPCs/ECs remains incompletely understood. In embryonic stem cell (ESC) differentiation culture and Etv2-null embryos, we show that Etv2 is dispensable for generating primitive Flk-1+/PDGFRα+ mesoderm but is required for the progression of Flk-1+/PDGFRα+ cells into vascular/hematopoietic mesoderm. Etv2-null ESCs and embryonic cells were arrested as Flk-1+/PDGFRα+ and failed to generate Flk-1+/PDGFRα− mesoderm. Flk-1+/Etv2+ early embryonic cells showed significantly higher hemato-endothelial potential than the Flk-1+/Etv2− population, suggesting that Etv2 specifies a hemato-endothelial subset of Flk-1+ mesoderm. Critical hemato-endothelial genes were severely down-regulated in Etv2-null Flk-1+ cells. Among those genes Scl, Fli1, and GATA2 were expressed simultaneously with Etv2 in early embryos and seemed to be critical targets. Etv2 reexpression in Etv2-null cells restored the development of CD41+, CD45+, and VE-cadherin+ cells. Expression of Scl or Fli1 alone could also restore HPCs/ECs in the Etv2-null background, indicating that these 2 genes are critical downstream targets. Furthermore, VEGF induced Etv2 potently and rapidly in Flk-1+ mesoderm. We propose that Flk-1+/PDGFRα+ primitive mesoderm is committed into Flk-1+/PDGFRα− vascular mesoderm through Etv2 and that up-regulation of Etv2 by VEGF promotes this commitment.
Value-Added Taxation: A Tax Whose Time Has Come?
Authors: Metcalf Gilbert E
Published: September 2011

Value-added taxes (VATs) are used in a large number of developed countries and have been under consideration at the national level in the United States in recent years. This paper provides an introduction to the tax for those unfamiliar with it. The author begins by describing how VATs work and briefly surveys their use by other countries. The remainder of the paper considers the economic impact as well as design issues that are likely to arise if the United States were to implement a VAT.
Cliometrics and the Nobel
Authors: Goldin Claudia
Published: September 2011

In October 1993, the Royal Swedish Academy of Sciences awarded the Nobel Prize in Economics to Robert William Fogel and Douglass Cecil North ‘for having renewed research in economic history.’ The Academy noted that ‘they were pioneers in the branch of economic history that has been called the ‘new economic history,’ or ‘cliometrics." In this paper, the author addresses what this cliometrics is and how these two Nobel Prize winners furthered the discipline of economics.
Human Capital vs. Signalling Explanations of Wages
Authors: Weiss Andrew
Published: September 2011

The key difference between signalling and human capital models is that signalling models allow firms to draw inferences about unobserved characteristics of workers. Those inferences can be based on the schooling or work experience of workers, or on direct measures of some aspects of job performance. Many recent empirical findings can be better explained by signalling models than by human capital theory. Given the explanatory power of signalling models, standard estimates of the social return to secondary schooling are in large part capturing differences in affective traits, such as perseverance, which were acquired either in primary school or at home.
Islamic Economics and the Islamic Subeconomy
Authors: Kuran Timur
Published: September 2011

Although Islamic economics was developed to serve cultural and political ends, efforts have been made to put its ideals into practice. There now exist Islamic banks, which claim to offer an interest-free alternative to conventional banking, and government-run Islamic redistribution systems, which were established to reduce inequalities. These institutions have not revolutionized the economic lives of Muslims. Yet, along with a wide variety of enterprises that have emerged outside the purview of Islamic economics, they have formed vibrant Islamic subeconomies in numerous metropolises. These subeconomies are expanding because they foster interpersonal trust and offer opportunities for guilt relief.
Plasmablastic lymphoma of the oral cavity in an HIV-positive patient: staging with 18F-FDG PET/CT
Authors: Makis William , Ciarallo Anthony , Lisbona Robert
Published: September 2011

Plasmablastic lymphoma of the oral cavity is a very rare and only recently recognized entity that has been identified almost exclusively in HIV-infected individuals. It has a predilection for the oral cavity, often exhibits very aggressive behavior and has a poor prognosis. The use of 18F-FDG PET/CT in the evaluation of HIV-associated lymphomas is a recent development, and its use in the staging of plasmablastic lymphoma of the oral cavity has not been previously reported. This rare report highlights the usefulness of 18F-FDG PET/CT in the staging of plasmablastic lymphoma of the oral cavity.
Characterization of phenolic compounds from inner bark of Betula pendula
Authors: Liimatainen Jaana , Karonen Maarit , Sinkkonen Jari , Helander Marjo , Salminen Juha-Pekka
Published: September 2011

A method has been developed for the characterization of biologically active silver birch (Betula pendula) inner bark phenolics based on high-performance liquid chromatography/diode array detector (HPLC-DAD)/electrospray ionization-mass spectrometry (ESI-MS). It was demonstrated that the inner bark contains high amounts of flavonoids, arylbutanoids, diarylheptanoids, simple phenolic compounds, phenolic acids, lignans, and procyanidins. Altogether, 30 individual compounds were characterized based on their ultraviolet (UV) and MS data. Structures of 22 compounds were confirmed by nuclear magnetic resonance (NMR) spectroscopy. In addition to previously reported phenolic compounds, 12 compounds were identified in silver birch inner bark for the first time; two of them are novel compounds: 3-β-glucopyranosyloxy-2-hydroxy-1-(4-hydroxy-3-methoxy-phenyl)-propan-1-one and 1,7-bis-(4-hydroxyphenyl)-3-heptanol 3-O-β-ap-iofuranosyl-(1→2)-β-glucopyranoside.
Extending the Symbolic Interactionist Theory of Interaction Processes: A Conceptual Outline
Authors: Turner Jonathan H.
Published: September 2011

This article outlines the elements of a more robust symbolic interactionist theory of interpersonal processes. I argue that George Herbert Mead's conceptualization of interaction processes can be extended to explain not only micro‐level social processes but also key elements of meso‐ and macro‐level dynamics. By expanding Mead's and more recent symbolic interactionist theorizing, and incorporating key ideas from other theoretical traditions outside symbolic interactionism proper, it becomes possible to develop a theory of interaction that fills in important conceptual gaps in theories on the dynamics of micro‐, meso‐, and macro‐level social phenomena.
“Scissors, Please”: The Practical Accomplishment of Surgical Work in the Operating Theater
Authors: Bezemer Jeff , Murtagh Ged , Cope Alexandra , Kress Gunther , Kneebone Roger
Published: September 2011

The focus of this article is on professional activity in the operating theater. We explore how surgeons and nurses organize their activities, how social interaction is used to help structure and define situations, and how differentials in knowledge are constructed and oriented to. We utilize some ideas and concepts from symbolic interactionism, ethnomethodology, and conversation analysis to analyze small clips of audio‐ and video‐recorded interaction. Focusing on how surgeons and nurses request, provide, and apply surgical instruments, the analysis shows how surgical work is accomplished through talk and bodily conduct. We conclude that, examined in detail, the social interaction between surgeons and nurses is analytically inseparable from the “technical” demands of their work.
Epigenetic reprogramming: is deamination key to active DNA demethylation?
Authors: Teperek-Tkacz Marta , Pasque Vincent , Gentsch George , Ferguson-Smith Anne C
Published: September 2011

DNA demethylation processes are important for reproduction, being central in epigenetic reprogramming during embryonic and germ cell development. While the enzymes methylating DNA have been known for many years, identification of factors capable of mediating active DNA demethylation has been challenging. Recent findings suggest that cytidine deaminases may be key players in active DNA demethylation. One of the most investigated candidates is activation-induced cytidine deaminase (AID), best known for its role in generating secondary antibody diversity in B cells. We evaluate evidence for cytidine deaminases in DNA demethylation pathways in vertebrates and discuss possible models for their targeting and activity regulation. These findings are also considered along with alternative demethylation pathways involving hydroxymethylation.
Energy requirements for waste water treatment
Authors: Svardal K. , Kroiss H.
Published: September 2011

The actual mathematical models describing global climate closely link the detected increase in global temperature to anthropogenic activity. The only energy source we can rely on in a long perspective is solar irradiation which is in the order of 10,000 kW/inhabitant. The actual primary power consumption (mainly based on fossil resources) in the developed countries is in the range of 5 to 10 kW/inhabitant. The total power contained in our nutrition is in the range of 0.11 kW/inhabitant. The organic pollution of domestic waste water corresponds to ∼0.018 kW/inhabitant. The nutrients contained in the waste water can also be converted into energy equivalents replacing market fertiliser production. This energy equivalent is in the range of 0.009 kW/inhabitant. Hence waste water will never be a relevant source of energy as long as our primary energy consumption is in the range of several kW/inhabitant. The annual mean primary power demand of conventional municipal waste water treatment with nutrient removal is in the range of 0.003–0.015 kW/inhabitant. In principle it is already possible to reduce this value for external energy supply to zero. Such plants should be connected to an electrical grid in order to keep investment costs low. Peak energy demand will be supported from the grid and surplus electric energy from the plant can be is fed to the grid. Zero ‘carbon footprint’ will not be affected by this solution. Energy minimisation must never negatively affect treatment efficiency because water quality conservation is more important for sustainable development than the possible reduction in energy demand. This argument is strongly supported by economical considerations as the fixed costs for waste water infrastructure are dominant.
Simulation of particle capture in a microfiltration membrane
Authors: Derekx Q. , Bacchin P. , Veyret D. , Glucina K. , Moulin P.
Published: September 2011

The present study takes an interest in the description of the fouling mechanisms by a numerical approach at the microscopic scale. At first, an X-ray tomography has enabled the modelling of the membrane structure for the numerical simulations. Next, for different particle size, a same volume of particles has been sent in the modelled membrane and the final permeability has been computed. Thus, the influence of the particle size on the fouling has been seen. An observation of the particles penetration in the membrane has been realised to detail this influence. The Hermia relations were used in order to determinate the predominant fouling mechanism or the succession of predominant fouling mechanisms. But, without an accurate calculation of the first derivative, it is not possible to define cleanly the predominant fouling mechanism for a low filtered volume. Nevertheless, the perspectives of the local approach with the numerical simulation seem interesting.
Older Persons' Reasoning about Responsibility for Health: Variations and Predictions
Authors: Kjellström Sofia , Ross Sara Nora
Published: September 2011

With many Western societies structured for adults to live longer and take responsibility for their health, it is valuable to investigate how older persons reason about this demand. Using mixed methods, this pilot studied how older persons reason about responsibility for health and their responsibility as a patient. Interviews with a small Swedish sample of 65–84 year olds were analyzed for qualitative characteristics and quantitative complexity in reasoning. Using adult development theory, we predicted at least three different stages of performance in reasoning. Results indicated four different stages: two where there is no actual reasoning about health and responsibility, and two where reasoning does occur, each qualitatively different. Results suggest a long-standing blind spot in health studies, that older people do not comprehend responsibility issues in the same way. There are significant implications for closing this gap between demand to take responsibility and capabilities to do so.
Loading Standardization of Postendodontic Restorations In Vitro: Impact of Restorative Stage, Static Loading, and Dynamic Loading
Authors: Sterzenbach G , Rosentritt M , Frankenberger R , Paris S , Naumann M
Published: September 2011

Objective

The load capability of post-restored endodontically treated teeth (ETT) can be determined at different restorative stages. It was the aim of this study to compare the load capability of ETT at these stages.

Materials and Methods

Maxillary central incisors were divided into 4 groups (n=10) and endodontically treated. Specimens were restored with: (I) only glass fiber posts (GFP); (II) GFP and composite build-up with 2 mm ferrule; (III and IV) with additional adhesively luted all-ceramic crowns. Group (I) to (III) were statically loaded, and group (IV) was exposed to thermomechanical loading (TML) and subsequent static loading.

Results

The lowest median load level of 73 N was determined for group (I). The maximum median load value of 331 N was found for group (III). The comparison of Fmax [N] of group (I), (II) and (III) revealed significant differences between the groups (p<0.001). The specimens of group (IV) failed at significantly lower load values (p<0.005) as similarly restored specimens of group (III) which were only statically loaded. The stage of restoration and TML loading prior to static loading had a significant impact on fracture patterns (p=0.006).

Conclusion

Every additional restorative step torwards a final crown-restored ETT significantly increased the load capability. TML prior to load-to-fracture testing of the complete restorative complex, ie. post, core and crown, significantly decreased maximum load capability.
Role of the Mannose Receptor (CD206) in Innate Immunity to Ricin Toxin
Authors: Gage Emily , Hernandez Maria O. , O’Hara Joanne M. , McCarthy Elizabeth A. , Mantis Nicholas J.
Published: September 2011

The entry of ricin toxin into macrophages and certain other cell types in the spleen and liver results in toxin-induced inflammation, tissue damage and organ failure. It has been proposed that uptake of ricin into macrophages is facilitated by the mannose receptor (MR; CD206), a C-type lectin known to recognize the oligosaccharide side chains on ricin’s A (RTA) and B (RTB) subunits. In this study, we confirmed that the MR does indeed promote ricin binding, uptake and killing of monocytes in vitro. To assess the role of MR in the pathogenesis of ricin in vivo, MR knockout (MR−/−) mice were challenged with the equivalent of 2.5× or 5× LD50 of ricin by intraperitoneal injection. We found that MR−/− mice were significantly more susceptible to toxin-induced death than their age-matched, wild-type control counterparts. These data are consistent with a role for the MR in scavenging and degradation of ricin, not facilitating its uptake and toxicity in vivo.
Some Fundamental Perspectives
Authors: Gottschalk P.
Published: September 2011

In this chapter, we cover some topics that contribute to a broader understanding of the role of IT outsourcing. We start by presenting value configurations consisting of primary and secondary activities in order to understand the role of IS/IT in different value configurations such as value chains, value shops, and value networks. Next, we look at electronic business infrastructure, where the extent of IT outsourcing can be determined by choosing from a list of 70 infrastructure services. E-business has a double role here, as an outsourced IT function more and more will be handled electronically. This means that the transactions between vendor and client after outsourcing will be conducted as electronic business. Third, we present a vendor value proposition that explains why a vendor may create value for the client because of its complementary competencies. Then, we look at IT function organization, outsourcing performance, and successful relationships. We conclude this chapter by discussing opportunities and threats in IT outsourcing.
An Image Edge Detection Method Based on Improved Ant Colony Algorithm
Authors: Wang Xi Yun , Huang Pan Feng , Fan Ying Pings
Published: September 2011

This paper raises an improved ant colony algorithm, for the detection of weak edge of complex background image, considering edge positioning accuracy, edge pixels, edge continuity and interference edges. This algorithm is improved in two aspects: first, we improved the expression of pheromone; second, we improved the calculation of Heuristic information. Compared with traditional Canny detector indicates, the improved method is proved to be accurate in edge detection, good continuity and less interference by experiment.
Half-Droptail: Algorithm to Mitigate LDoS Attacks
Authors: Zhang Jing , Hu Hua Ping , Liu Bo , Chen Lin
Published: September 2011

Low-Rate Denial-of-Service (LDoS) attack was a new type of denial-of-service attack, the queue management algorithm were found valuable to this attack, especially Droptail. In this paper, based on the impacts of the parameter setting of the Droptail on the LDoS attack, we proposed the Half-Droptail algorithm by changing parameter on the queue management algorithm. We made a set simulation of this algorithm, and the results show that the algorithm can effectively improve the defense performance of algorithm itself.
Online Multi-Attribute Reverse Auction Mechanism Design Based on Utility
Authors: Zhou Yan Yue , Li Chen , Zhu Ge
Published: September 2011

A good auction mechanism is able to release the information who owns to the other side who lacks of. In order to ensure a positive flow of information and to improve the active participation of suppliers, negotiation mechanism is introduced, and suppliers can participate in the design of auction mechanism. Several rounds of English auction is applied to determining the final winner. Taking into account that the buyer has a preference on the property, we use AHP to calculate final weights, and use multi-attribute utility function to calculate the greatest utility as the winner.
Growth and Experimental Evidence of Quantum Confinement Effects in Cu2O and CuO Thin Films
Authors: Pappas S.D. , Poulopoulos Panagiotis , Kapaklis Vassilios , Grammatikopoulos S. , Trachylis D. , Velgakis M.J. , Meletis Efstathios I. , Politis C.
Published: September 2011

Thin Cu films of thickness 0.4 – 150 nm were deposited via radio frequency magnetron sputtering on Si(100) wafers, corning glass and quartz. Subsequently the Cu films were oxidized in ambient air at 230oC and 425oC in order to produce single-phase Cu2O and CuO, respectively. Selected samples were measured in the transmission geometry with the help of an ultraviolet – visible spectrophotometer. From the absorption spectra of the films, it was found that the gap EB for the dipole allowed transitions showed blue shifts of about 1.2 eV for the Cu2O thinnest film (0.75 nm), whereas the Edirect for the direct gap transitions showed blue shifts of about 0.16 eV for the CuO thinnest film (0.7 nm). The blue shift of the energy gap in the copper-oxide semiconductors is an indication of the presence of strong quantum confinement effects.
T Cell Dynamics during Induction of Tolerance and Suppression of Experimental Allergic Encephalomyelitis
Authors: Divekar Rohit D. , Haymaker Cara L. , Cascio Jason A. , Guloglu Betul F. , Ellis Jason S. , Tartar Danielle M. , Hoeman Christine M. , Franklin Craig L. , Zinselmeyer Bernd H. , Lynch Jennifer N. , Miller Mark J. , Zaghouani Habib
Published: September 2011

The cell dynamics associated with induction of peripheral T cell tolerance remain largely undefined. In this study, an in vivo model was adapted to two-photon microscopy imaging, and T cell behavior was analyzed on tolerogen-induced modulation. FcγR-deficient (FcγR−/−) mice were unable to resist or alleviate experimental allergic encephalomyelitis when treated with Ig-myelin oligodendrocyte glycoprotein (MOG) tolerogen, an Ig carrying the MOG35–55 peptide. However, when FcγR+/+ dendritic cells (DCs) are adoptively transferred into FcγR−/− mice, uptake and presentation of Ig-MOG occurs and the animals were able to overcome experimental allergic encephalomyelitis. We then fluorescently labeled FcγR+/+ DCs and 2D2 MOG-specific TCR-transgenic T cells, transferred them into FcγR−/− mice, administered Ig-MOG, and analyzed both T cell–DC contact events and T cell motility. The results indicate that tolerance takes place in lymphoid organs, and surprisingly, the T cells do not become anergic but instead have a Th2 phenotype. The tolerant Th2 cells displayed reduced motility after tolerogen exposure similar to Th1 cells after immunization. However, the Th2 cells had higher migration speeds and took longer to exhibit changes in motility. Therefore, both Th1 immunity and Th2 tolerance alter T cell migration on Ag recognition, but the kinetics of this effect differ among the subsets.
Sensitization to Gliadin Induces Moderate Enteropathy and Insulitis in Nonobese Diabetic-DQ8 Mice
Authors: Galipeau Heather J. , Rulli Nestor E. , Jury Jennifer , Huang Xianxi , Araya Romina , Murray Joseph A. , David Chella S. , Chirdo Fernando G. , McCoy Kathy D. , Verdu Elena F.
Published: September 2011

Celiac disease (CD) is frequently diagnosed in patients with type 1 diabetes (T1D), and T1D patients can exhibit Abs against tissue transglutaminase, the auto-antigen in CD. Thus, gliadin, the trigger in CD, has been suggested to have a role in T1D pathogenesis. The objective of this study was to investigate whether gliadin contributes to enteropathy and insulitis in NOD-DQ8 mice, an animal model that does not spontaneously develop T1D. Gliadin-sensitized NOD-DQ8 mice developed moderate enteropathy, intraepithelial lymphocytosis, and barrier dysfunction, but not insulitis. Administration of anti-CD25 mAbs before gliadin-sensitization induced partial depletion of CD25+Foxp3+ T cells and led to severe insulitis, but did not exacerbate mucosal dysfunction. CD4+ T cells isolated from pancreatic lymph nodes of mice that developed insulitis showed increased proliferation and proinflammatory cytokines after incubation with gliadin but not with BSA. CD4+ T cells isolated from nonsensitized controls did not response to gliadin or BSA. In conclusion, gliadin sensitization induced moderate enteropathy in NOD-DQ8 mice. However, insulitis development required gliadin-sensitization and partial systemic depletion of CD25+Foxp3+ T cells. This humanized murine model provides a mechanistic link to explain how the mucosal intolerance to a dietary protein can lead to insulitis in the presence of partial regulatory T cell deficiency.
IL-21–Dependent B Cell Death Driven by Prostaglandin E2, a Product Secreted from Follicular Dendritic Cells
Authors: Magari Masaki , Nishikawa Yumiko , Fujii Yasumasa , Nishio Yumi , Watanabe Koji , Fujiwara Michiya , Kanayama Naoki , Ohmori Hitoshi
Published: September 2011

In germinal centers (GCs), B cells are selected through interaction with follicular dendritic cells bearing immune complexes and follicular helper T (Tfh) cells secreting Tfh cytokines, including IL-21. To analyze these cellular interactions, we have explored culture conditions that can simulate GC B cell selection in vitro using a mouse follicular dendritic cell line, FL-YB. FL-YB cells efficiently enhanced viability of cocultured mouse B cells in a BAFF-dependent fashion. Interestingly, we found that addition of IL-21, a major Tfh cytokine, readily induced death of B cells that were cocultured with FL-YB cells, whereas IL-21 alone sustained viability of B cells in the absence of FL-YB cells. The IL-21–induced death was dependent on a low m.w. soluble factor that was released from FL-YB cells, which was finally identified as PGE2. Treatment of B cells with IL-21 plus PGE2, but not either alone, resulted in enhanced expression of a proapoptotic protein Bim and the upstream transcription factor Foxo1. A PGE2 receptor isoform, EP4, was responsible for IL-21/PGE2–induced B cell death. Thus, PGE2 is an endogenous chemical mediator that can switch pleiotropic actions of IL-21 on B cells. IL-21/PGE2–induced B cell death was rescued if B cells were costimulated via CD40. In immunized mice, deficiency of IL-21R in B cells led to a significant decrease in the frequency of activated caspase-3–positive GC B cells concomitant with impaired affinity maturation of Abs. Taken together, results implicate a physiological role of IL-21/PGE2–induced B cell death in GC B cell selection.
Hypoxia-Dependent Inhibition of Tumor Cell Susceptibility to CTL-Mediated Lysis Involves NANOG Induction in Target Cells
Authors: Hasmim Meriem , Noman Muhammad Zaeem , Lauriol Jessica , Benlalam Houssem , Mallavialle Aude , Rosselli Filippo , Mami-Chouaib Fathia , Alcaide-Loridan Catherine , Chouaib Salem
Published: September 2011

Hypoxia is a major feature of the solid tumor microenvironment and is known to be associated with tumor progression and poor clinical outcome. Recently, we reported that hypoxia protects human non-small cell lung tumor cells from specific lysis by stabilizing hypoxia-inducible factor-1α and inducing STAT3 phosphorylation. In this study, we show that NANOG, a transcription factor associated with stem cell self renewal, is a new mediator of hypoxia-induced resistance to specific lysis. Our data indicate that under hypoxic conditions, NANOG is induced at both transcriptional and translational levels. Knockdown of the NANOG gene in hypoxic tumor cells is able to significantly attenuate hypoxia-induced tumor resistance to CTL-dependent killing. Such knockdown correlates with an increase of target cell death and an inhibition of hypoxia-induced delay of DNA replication in these cells. Interestingly, NANOG depletion results in inhibition of STAT3 phosphorylation and nuclear translocation. To our knowledge, this study is the first to show that hypoxia-induced NANOG plays a critical role in tumor cell response to hypoxia and promotes tumor cell resistance to Ag-specific lysis.
Synthesis and application of virus‐based hybrid nanomaterials
Authors: Lee Sang‐Yup , Lim Jung‐Sun , Harris Michael T.
Published: September 2011

A virus is a nanoscaled biomolecular substance composed of genes, protecting capsid proteins, and envelopes. The nanoscale dimensions and surface functionalities of virions have been exploited to attract and assemble inorganic and organic materials to produce functional nanomaterials with large surface areas. Genetic modifications of virus capsid proteins lead to the selective deposition and controlled growth of inorganic substances producing organized virus‐based hybrid materials. Due to these properties, viruses hold promise for development as platforms for the creation of hybrid materials with multiple functionalities. This article reviews the characteristics of commonly used viruses and their fabrication into virus‐based hybrid materials that have been applied in engineering applications such as nanowires and catalysts. Biotechnol. Bioeng. 2012;109: 16–30. © 2011 Wiley Periodicals, Inc.
Graphene Oxide Noncovalent Photosensitizer and Its Anticancer Activity In Vitro
Authors: Zhou Lin , Wang Wei , Tang Jing , Zhou Jia‐Hong , Jiang Hui‐Jun , Shen Jian
Published: September 2011

Graphene oxide (GO) was investigated as a potential drug‐delivery system due to its special properties and biocompatibility. Thus far, little has been done to use GO as a photosensitive drug‐delivery system and to explore its anticancer activity in vitro in photodynamic therapy applications. Here, a novel GO–hypocrellin A (GO‐HA) hybrid was prepared by a simple noncovalent method and its photodynamic activity was studied for the first time. The results showed that an efficient loading amount of HA on GO was as high as 1.0 mg mg−1 and the stability of the hybrid was superior to that of the free hypocrellin A in aqueous solution. Furthermore, GO‐HA can be excited by irradiation with light of appropriate wavelength to generate singlet oxygen, and in vitro experiments illustrated that GO‐HA was efficiently taken up by tumor cells, and that light irradiation of such impregnated cells resulted in significant cell death. Thus, these properties of GO‐HA could possibly make it especially promising for use in clinical photodynamic therapy.
A Lewis Acidity Scale in Relation to Rate Constants of Lewis Acid Catalyzed Organic Reactions
Authors: Hilt Gerhard , Pünner Florian , Möbus Juri , Naseri Vesal , Bohn Martin A.
Published: September 2011

The quantification of Lewis acidity is accomplished by a deuterated quinolizidine probe utilizing 2H NMR spectroscopy. The chemical shifts of the 2H NMR signals for aluminum, boron, titanium, and zinc halides are reported. The rate constants for Lewis acid catalyzed reactions were determined by utilizing UV/Vis spectroscopy for Diels–Alder and Povarov reactions under pseudo‐first‐order conditions. The magnitude of the 2H NMR chemical shifts correlates with the rate constants of the organic transformations for many Lewis acids investigated in the same order, whereas some deviations are identified.
Characteristics of concentrated flow hydraulics for rangeland ecosystems: implications for hydrologic modeling
Authors: Al‐Hamdan Osama Z. , Pierson F.B. , Nearing M.A. , Stone J.J. , Williams C.J. , Moffet C.A. , Kormos P.R. , Boll J. , Weltz M.A.
Published: September 2011

Concentrated flow is often the dominant source of water erosion following disturbance on rangelands. Because of the lack of studies that explain the hydraulics of concentrated flow on rangelands, cropland‐based equations have typically been used for rangeland hydrology and erosion modeling, leading to less accurate predictions due to different soil and vegetation cover characteristics. This study investigates the hydraulics of concentrated flow using unconfined field experimental data over diverse rangeland landscapes within the Great Basin Region, United States. The results imply that the overall hydraulics of concentrated flow on rangelands differ significantly from those of cropland rills. Concentrated flow hydraulics on rangelands are largely controlled by the amount of cover or bare soil and hillslope angle. New predictive equations for concentrated flow velocity (R2 = 0·47), hydraulic friction (R2 = 0·52), and width (R2 = 0·4) representing a diverse set of rangeland environments were developed. The resulting equations are applicable across a wide span of ecological sites, soils, slopes, and vegetation and ground cover conditions and can be used by physically‐based rangeland hydrology and erosion models to estimate rangeland concentrated flow hydraulic parameters. Published in 2011. This article is a US Government work and is in the public domain in the USA.
Antimicrobial, Mosquito Larvicidal and Antioxidant Properties of the Leaf and Rhizome of Hedychium coronarium
Authors: Ho Jiau‐Ching
Published: September 2011

The essential oil, methanolic and aqueous extracts of the leaves and rhizomes of Hedychium coronarium Koen. (Zingiberaceae) were assayed for their antimicrobial, mosquito larvicidal and antioxidant properties. The chemical composition of the essential oil of two organs was analyzed by GC/MS analysis. β‐Pinene (33.9%), α‐pinene (14.7%), 1,8‐cineole (13.3%), r‐elemene (11.0%) and carotol (9.1%) were the main components in the leaf oil, including 82.0% terpenoid compounds. The major constituents of the rhizome oil were 1,8‐cineole (37.3%), β‐pinene (23.0%), α‐terpineol (10.4%) and α‐pinene (9.9%), comprising 80.6% of the oil. The leaf and rhizome essential oil displayed significant antimicrobial activity, as determined by the disc‐diffusion method, inhibiting the growth of all five fungal and four bacterial strains tested. The antimicrobial nature of the essential oil is related to high terpenoid contents. The leaf oil exhibited the mosquito larvicidal activity with 2 h and 24 h LC50 values of 111 and 90 ppm, respectively, while the rhizome oil showed the larvicidal activity with 2 h and 24 h LC50 values of 86 and 47 ppm, respectively. β‐Pinene, α‐pinene and 1,8‐cineol in H. coronarium serve as the principal larvicidal components of both oils. The individual antioxidant assays such as DPPH scavenging activity, chelating effect of ferrous ions and reducing power have been used. The present study demonstrated that the polar extracts of H. coronarium possessed anti‐oxidant. Appreciable total phenolic content (18.5‐26.3 mg/g) was also detected by Folin‐Ciocalteu test.
Hospitalists assess the causes of early hospital readmissions
Authors: Koekkoek Douglas , Bayley K. Bruce , Brown Allen , Rustvold D. Leif
Published: September 2011

BACKGROUND:

Hospital readmissions are receiving increasing attention as an indicator of health care quality and waste. Hospitalists provide a unique perspective on the underlying processes that result in acute care readmissions and the extent to which readmissions can be prevented.

OBJECTIVE:

The study assessed the views of hospitalists on the preventability of readmissions and the most important ways to prevent future readmissions.

DESIGN AND MEASUREMENTS:

A group of 17 hospitalists serving four community hospitals reviewed the details of 300 consecutive 21‐day readmissions. Each used a structured data collection form to code information from inpatient and outpatient charts on patient characteristics, process measures, preventability, and potential interventions.

RESULTS:

Overall, 15% of readmissions were rated as overtly preventable, but with wide variation among hospitalists in their ratings of preventability. Perceptions of preventability appear to be a function of readmission timing, the similarity of diagnoses between admissions, medication issues, and the presence of certain chronic diseases (eg, chronic obstructive pulmonary disease [COPD]). Hospitalists were more likely to recommend familiar interventions under their control for a readmissions termed preventable, such as extending the initial hospital stay or addressing medications and patient education at discharge. They less often identified outpatient case management, home services, or physician nursing home visits as viable prevention strategies.

CONCLUSIONS:

The study points to the multifactorial nature of interventions needed to prevent readmissions, the tradeoffs between hospital length of stay and readmission, and the importance of fostering a culture of optimism and engagement to outpatient components of the health system to reduce hospital readmissions. Journal of Hospital Medicine 2011. © 2011 Society of Hospital Medicine
Expression and purification of an isotopically labeled aggregation prone inducible nitric oxide synthase calmodulin‐binding protein for use in nuclear magnetic resonance studies
Authors: Piazza Michael , Duangkham Yay , Spratt Donald E. , Dieckmann Thorsten , Guillemette J. Guy
Published: September 2011

Nuclear magnetic resonance (NMR) spectroscopy is an efficient method for studying the dynamics and structures of protein‐protein and protein‐peptide complexes. Calmodulin (CaM), a ubiquitous Ca2+‐sensing protein, is able to bind and regulate various intracellular proteins, including the nitric oxide synthase (NOS) enzymes. The investigation of CaM bound to the CaM‐binding region of the inducible nitric oxide synthase (iNOS) isoform of NOS proved to be difficult due to the propensity of the iNOS CaM‐binding domain to aggregate when not bound to CaM. In the present study, an isotopically labeled peptide of the CaM‐binding region of iNOS has successfully been expressed and purified. The peptide identity was verified by both sodium dodecyl sulfate polyacrylamide gel electrophoresis and mass spectroscopy and further characterized by NMR spectroscopy. These results demonstrate an efficient approach for the expression and purification of individually stable isotope labeled protein complexes for NMR analysis, even if one partner is prone to aggregation or has very low solubility. This technique can also be used to label a specific type of amino acid or radiolabel all of the amino acids in one of the components participating in a protein–protein or protein–peptide complex.
Resilin in dragonfly and damselfly wings and its implications for wing flexibility
Authors: Donoughe Seth , Crall James D. , Merz Rachel A. , Combes Stacey A.
Published: September 2011

Although there is mounting evidence that passive mechanical dynamics of insect wings play an integral role in insect flight, our understanding of the structural details underlying insect wing flexibility remains incomplete. Here, we use comparative morphological and mechanical techniques to illuminate the function and diversity of two mechanisms within Odonata wings presumed to affect dynamic wing deformations: flexible resilin vein‐joints and cuticular spikes. Mechanical tests show that joints with more resilin have lower rotational stiffness and deform more in response to a load applied to an intact wing. Morphological studies of 12 species of Odonata reveal that resilin joints and cuticular spikes are widespread taxonomically, yet both traits display a striking degree of morphological and functional diversity that follows taxonomically distinct patterns. Interestingly, damselfly wings (suborder Zygoptera) are mainly characterized by vein‐joints that are double‐sided (containing resilin both dorsally and ventrally), whereas dragonfly wings (suborder Epiprocta) are largely characterized by single‐sided vein‐joints (containing resilin either ventrally or dorsally, but not both). The functional significance and diversity of resilin joints and cuticular spikes could yield insight into the evolutionary relationship between form and function of wings, as well as revealing basic principles of insect wing mechanical design. J. Morphol., 2011. © 2011 Wiley‐Liss, Inc.
Numerical calculation of AC substation grounding systems buried in a vertical multilayered earth model by higher‐order basis function
Authors: Li Zhong‐Xin , Fan Jian‐Bin , Yin Yu
Published: September 2011

To study the accuracy of numerical simulations for an AC substation grounding problem embedded in a vertical multilayered earth model, this paper proposes a novel algorithm combining the rapidly convergent one‐dimensional Galerkin's BEM with higher‐order basis functions on the basis of the quasi‐static electric field theory. General analytical formulas for the mutual impedance between any pair of short line conductors are also derived to accelerate the numerical integration. These formulas can work in not only complex space but also real space because of our application of the quasi‐static complex image method, which is different from the contribution of other earlier scientists, whose formula can work just in real space. The algorithm can be used to simulate and analyze any grounding system, including those incorporating a floating grid located anywhere in the earth model. Copyright © 2011 John Wiley & Sons, Ltd.
Rheology and processability of polyamide66 filled with different‐sized and size‐distributed calcium carbonate
Authors: Zhang Jun , Wu Jun‐Li , Mo Hong , Ma Zhen‐Mao , Zhou Ning‐lin , Yuan Jiang , Shen Jian
Published: September 2011

Two‐sized calcium carbonates (CaCO3) were blended and filled into polyamide66 (PA66). The shear viscosity of PA66/CaCO3 composites was measured with a capillary extrusion rheometer. The results showed that the shear viscosity of the efficient size distribution samples (PA66 was filled with 600/2500 mesh CaCO3 blending) obviously decreased compared with that of the single‐size distribution samples (PA66 was filled with 600 or 2500 mesh CaCO3). The shear viscosity of PA66/CaCO3 composites at different temperatures was also studied. The results showed that the flow activation energy and flow activation entropy of the efficient size distribution samples obviously increased compared with those of the single‐size distribution samples. The change in flow activation entropy was used to explain the experimental results of shear viscosity. The processability of PA66/CaCO3 composites was evaluated with a HAAKE torque rheometer. The results showed that the processability of the efficient size distribution samples was obviously improved and the best efficiency of processability improvement appeared in the 30 wt% CaCO3 content. POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers
Specific nonlinear viscoelasticity behaviors of natural rubber and zinc dimethacrylate composites due to multi‐crosslinking bond interaction by using rubber process analyzer 2000
Authors: Chen Yukun , Xu Chuanhui
Published: September 2011

In this paper, the dynamic mechanical properties of the natural rubber (NR) which was filled with in situ zinc dimethacrylate (ZDMA) were investigated using a Rubber Process Analyzer (RPA2000). A weak rigid filler–filler network was formed in the uncured NR/ZDMA compounds. Pronounced Payne effect and stress‐softening behavior were observed in the vulcanizates, which indicated that a strong and special filler structure was formed after vulcanization. However, an ionic network might be formed with a high ZDMA loading, which was not favorable to rebuild the poly‐ZDMA network. Finally, two tentative regions of networks deformation during the dynamic strain sweep were discussed: filler–filler and ionic bonds dominating region and rubber network dominating region. POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers
Prescription‐acquired acetaminophen use and potential overuse patterns: 2001–2008
Authors: Gokhale Mugdha , Martin Bradley C.
Published: September 2011

Background

Food and Drug Administration advisory committees recently made some recommendations to address acetaminophen (APAP)‐related toxicity.

Objectives

To study the proportion of APAP users potentially consuming APAP over the currently recommended dosage (4 g/day) and a toxic dosage (10 g/day). To explore the impact of substituting the APAP strength in combination prescriptions to 325 mg on potential APAP overuse patterns.

Methods

Using the 2001–2008 pharmacy claims from IMS LifeLink Health Plans, APAP potential maximum daily dose (PMDD), potential cumulative dose, and potential average daily dose (PADD) were calculated annually for APAP users. The proportion of users with potential APAP use above 4 g/day and 10 g/day are reported. Analyses were repeated by substituting the maximum APAP strength in combination prescriptions to 325 mg. Ordinary least squares regression was used to detect linear trends in APAP use/overuse.

Results

790 188 of 2 656 161 study subjects were prescribed APAP in one or more years from 2001 to 2008. 32.62% and 26.84% of the adult APAP users had a PMDD > 4 gm/day in 2001 and 2008 while 1.88% and 3.17% had a PMDD > 10 gm/day. If the maximum APAP strength in combination prescriptions was 325 mg, the proportion of APAP users with PMDD > 4 g would be 14.08% in 2001 and 13.67% in 2008, whereas the proportion of those with PMDD > 10 g would be 0.21% and 2.30%, respectively.

Conclusion

About one in four APAP users have a PMDD > 4 g/day, whereas 2–3% have a PMDD > 10 g based exclusively on prescription data, which is concerning. These proportions could reduce by over half if the maximum APAP strength in combination prescriptions is 325 mg. Additional monitoring of opioid prescription‐patterns, physician and pharmacist cognizance in prescribing APAP‐containing combination products, and dose‐reduction strategies should be considered to reduce APAP overuse. Copyright © 2011 John Wiley & Sons, Ltd.
Effect of the induced electron traps by oxygen plasma treatment on transfer characteristics of organic thin film transistors
Authors: Huang Bo-Chieh , Lin Yow-Jon
Published: September 2011

The effect of the induced electron traps by oxygen plasma treatment on transfer characteristics of organic thin film transistors (OTFTs) was researched in this study. From the observed result, the relationship between electron trapping and electrical stability of OTFTs was discussed. It is shown that oxygen plasma treatment may lead to a shift of the threshold voltage towards positive gate-source voltages and an increase in the mobility, resulting from the incorporation of oxygen and the passivation of the defects in the grain-boundary region. It is found that the electrical stability mainly arises from the increased long-lifetime electron-trap density.
Strong reproductive isolation between humans and Neanderthals inferred from observed patterns of introgression
Authors: Currat Mathias , Excoffier Laurent
Published: September 2011

Recent studies have revealed that 2–3% of the genome of non-Africans might come from Neanderthals, suggesting a more complex scenario of modern human evolution than previously anticipated. In this paper, we use a model of admixture during a spatial expansion to study the hybridization of Neanderthals with modern humans during their spread out of Africa. We find that observed low levels of Neanderthal ancestry in Eurasians are compatible with a very low rate of interbreeding (<2%), potentially attributable to a very strong avoidance of interspecific matings, a low fitness of hybrids, or both. These results suggesting the presence of very effective barriers to gene flow between the two species are robust to uncertainties about the exact demography of the Paleolithic populations, and they are also found to be compatible with the observed lack of mtDNA introgression. Our model additionally suggests that similarly low levels of introgression in Europe and Asia may result from distinct admixture events having occurred beyond the Middle East, after the split of Europeans and Asians. This hypothesis could be tested because it predicts that different components of Neanderthal ancestry should be present in Europeans and in Asians.