bluuebunny/crossref_metadata_2025 huggingface dataset:
WEAK LOCALIZATION AND ITS APPLICATIONS AS AN EXPERIMENTAL TOOL
Authors: Bergmann Gerd
Published: June 2010

The resistance of two-dimensional electron systems such as thin disordered films shows deviations from Boltzmann theory, which are caused by quantum corrections and are called weak localization. The theoretical origin of weak localization is the Langer–Neal graph in Kubo formalism. It represents an interference experiment with conduction electrons split into pairs of waves interfering in the back-scattering direction. The intensity of the interference (integrated over the time) can easily be measured by the resistance of the film. The application of a magnetic field B destroys the phase coherence after a time which is proportional to 1/B. For a field of 1 T this time is of the order of 1 ps. Therefore with a dc experiment, one can measure characteristic times of the electron system in the range of picoseconds. Weak localization has been applied to measure dephasing, spin-orbit scattering, tunneling times, etc. One important field of application is the investigation of magnetic systems and magnetic impurities by measuring the magnetic dephasing time and its temperature dependence. Here the Kondo maximum of spin-flip scattering, spin-fluctuations, Fermi liquid behavior and magnetic d-resonances have been investigated. Another field is the detection of magnetic moments for very dilute alloys and surface impurities. This article given a brief survey of different applications of weak localization with a focus on magnetic impurities.
Ionic Liquids in Analytical Chemistry
Authors: Soukup-Hein Renee J. , Warnke Molly M. , Armstrong Daniel W.
Published: June 2010

The role of ionic liquids (ILs) in analytical chemistry is increasing substantially every year. A decade ago there were but a handful of papers in this area of research that were considered curiosities at best. Today, those publications are recognized as seminal articles that gave rise to one of the most rapidly expanding areas of research in chemical analysis. In this review, we briefly highlight early work involving ILs and discuss the most recent advances in separations, mass spectrometry, spectroscopy, and electroanalytical chemistry. Many of the most important advances in these fields depend on the development of new, often unique ILs and multifunctional ILs. A better understanding of the chemical and physical properties of ILs is also essential.
Applications of Polymer Brushes in Protein Analysis and Purification
Authors: Jain Parul , Baker Gregory L. , Bruening Merlin L.
Published: June 2010

This review examines the application of polymer brush–modified flat surfaces, membranes, and beads for protein immobilization and isolation. Modification of porous substrates with brushes yields membranes that selectively bind tagged proteins to give 99% pure protein at capacities as high as 100 mg of protein per cubic centimeter of membrane. Moreover, enrichment of phosphopeptides on brush-modified matrix-assisted laser desorption/ionization (MALDI) plates allows detection and characterization of femtomole levels of phosphopeptides by MALDI mass spectrometry. Because swollen hydrophilic brushes can resist nonspecific protein adsorption while immobilizing a high density of proteins, they are attractive as substrates for protein microarrays. This review highlights the advantages of polymer brush–modified surfaces over self-assembled monolayers and identifies some research needs in this area.
Scanning Tunneling Spectroscopy
Authors: Zandvliet Harold J.W. , van Houselt Arie
Published: June 2010

The scanning tunneling microscope (STM) has revolutionized our ability to explore and manipulate atomic-scale solid surfaces. In addition to its unparalleled spatial power, the STM can study dynamical processes, such as molecular conformational changes, by recording current traces as a function of time. It can also be employed to measure the physical properties of molecules or nanostructures down to the atomic scale. Combining STM imaging with measurement of current–voltage (I–V) characteristics [i.e., scanning tunneling spectroscopy (STS)] at similar resolution makes it possible to obtain a detailed map of the electronic structure of a surface. For many years, STM lacked chemical specificity; however, the recent development of STM–IETS (inelastic electron tunneling spectroscopy) has allowed us to measure the vibrational spectrum of a single molecule. This review introduces and illustrates these recent developments with a few simple scholarly examples.
Analysis of Genes, Transcripts, and Proteins via DNA Ligation
Authors: Conze Tim , Shetye Alysha , Tanaka Yuki , Gu Jijuan , Larsson Chatarina , Göransson Jenny , Tavoosidana Gholamreza , Söderberg Ola , Nilsson Mats , Landegren Ulf
Published: June 2010

Analytical reactions in which short DNA strands are used in combination with DNA ligases have proven useful for measuring, decoding, and locating most classes of macromolecules. Given the need to accumulate large amounts of precise molecular information from biological systems in research and in diagnostics, ligation reactions will continue to offer valuable strategies for advanced analytical reactions. Here, we provide a basis for further development of methods by reviewing the history of analytical ligation reactions, discussing the properties of ligation reactions that render them suitable for engineering novel assays, describing a wide range of successful ligase-based assays, and briefly considering future directions.
Ultrahigh-Mass Mass Spectrometry of Single Biomolecules and Bioparticles
Authors: Chang Huan-Cheng
Published: June 2010

Since the advent of soft ionization methods, mass spectrometry (MS) has found widespread application in the life sciences. Mass is now known to be a critical parameter for characterization of biomolecules and their complexes; it is also a useful parameter to characterize bioparticles such as viruses and cells. However, because of the genetic diversity of these entities, it is necessary to measure their masses individually and to obtain the corresponding mean masses and mass distributions. Here, I review recent technological developments that enable mass measurement of ultrahigh-mass biomolecules and bioparticles at the single-ion level. Some representative examples include cryodetection time-of-flight MS of single-megadalton protein ions, Millikan-type mass measurements of single viruses in a cylindrical ion trap, and charge-detection quadrupole ion trap MS of single whole cells. I also discuss the promises and challenges of these new technologies in real-world applications.
Forensic Chemistry
Authors: Bell Suzanne
Published: June 2010

Forensic chemistry is unique among chemical sciences in that its research, practice, and presentation must meet the needs of both the scientific and the legal communities. As such, forensic chemistry research is applied and derivative by nature and design, and it emphasizes metrology (the science of measurement) and validation. Forensic chemistry has moved away from its analytical roots and is incorporating a broader spectrum of chemical sciences. Existing forensic practices are being revisited as the purview of forensic chemistry extends outward from drug analysis and toxicology into such diverse areas as combustion chemistry, materials science, and pattern evidence.
Expression of Nestin, Vimentin, and NCAM by Renal Interstitial Cells after Ischemic Tubular Injury
Authors: Vansthertem David , Gossiaux Annabel , Declèves Anne-Emilie , Caron Nathalie , Nonclercq Denis , Legrand Alexandre , Toubeau Gérard
Published: June 2010

This work explores the distribution of various markers expressed by interstitial cells in rat kidneys after ischemic injury (35 minutes) during regeneration of S3 tubules of outer stripe of outer medulla (OSOM). Groups of experimental animals (n=4) were sacrificed every two hours during the first 24 hours post-ischemia as well as 2, 3, 7, 14 days post-ischemia. The occurrence of lineage markers was analyzed on kidney sections by immunohistochemistry and morphometry during the process of tubular regeneration. In postischemic kidneys, interstitial cell proliferation, assessed by 5-bromo-2′-deoxyuridine (BrdU) and Proliferating Cell Nuclear Antigen (PCNA) labeling, was prominent in outer medulla and reach a maximum between 24 and 72 hours after reperfusion. This population was characterized by the coexpression of vimentin and nestin. The density of -Neural Cell Adhesion Molecule (NCAM) positive interstitial cells increased transiently (18–72 hours) in the vicinity of altered tubules. We have also localized a small population ofα-Smooth Muscle Actin (SMA)-positive cells confined to chronically altered areas and characterized by a small proliferative index. In conclusion, we observed in the postischemic kidney a marked proliferation of interstitial cells that underwent transient phenotypical modifications. These interstitial cells could be implicated in processes leading to renal fibrosis.
Distorted Wave Theories Applied to Double Ionization by Ion Impact: Simulation of Higher-Order Processes
Authors: Ciappina M. F. , Kirchner T. , Schulz M. , Fischer D. , Moshammer R. , Ullrich J.
Published: June 2010

One of the goals in studies of double ionization (DI) of simple atoms by electron
or ion impact is to elucidate and assess the different mechanisms that lead to this
atomic process. In this work we present an attempt to model the mechanisms beyond
the first order in DI of helium by highly charged projectiles. To this end we
employ the continuum distorted wave-eikonal initial state (CDW-EIS) formalism
joint with a Monte Carlo event generator (MCEG). The MCEG allows us to generate
theoretical event files that represent the counterpart of the data obtained from
a kinematically complete experiment. Starting from these event files, a new data
analysis tool used to contrast theory and experiment in DI, the four-body Dalitz
plots, is easily produced. The higher order mechanisms are simulated by considering
DI as a sequential process: a single ionization of a helium atom as a first step and
another single ionization of a single-charged helium ion as a second step. Some of
the features in the experimental data are very well reproduced by these simulations.
Carbon Monoxide as an Electron Donor for the Biological Reduction of Sulphate
Authors: Parshina Sofiya N. , Sipma Jan , Henstra Anne Meint , Stams Alfons J. M.
Published: June 2010

Several strains of Gram-negative and Gram-positive sulphate-reducing bacteria (SRB) are able to use carbon monoxide (CO) as a carbon source and electron donor for biological sulphate reduction. These strains exhibit variable resistance to CO toxicity. The most resistant SRB can grow and use CO as an electron donor at concentrations up to 100%, whereas others are already severely inhibited at CO concentrations as low as 1-2%. Here, the utilization, inhibition characteristics, and enzymology of CO metabolism as well as the current state of genomics of CO-oxidizing SRB are reviewed. Carboxydotrophic sulphate-reducing bacteria can be applied for biological sulphate reduction with synthesis gas (a mixture of hydrogen and carbon monoxide) as an electron donor.
First Record of Trophobiotic Interaction between a Ponerine Ant and a Cicadelid Bug
Authors: Souza Thadeu Sobral , Francini Ronaldo B.
Published: June 2010

The interactions of the antOdontomachus bauriwith nymphs of the sap-sucking bugXedreota tuberculata(Cicadellidae: Ledrinae) were studied onSipaneaaff. (Rubiaceae) along a trail in an upland forest in the Ecological Reserve of Anavilhanas, AM, Brazil. Five complete interactions at day and at night (about 60 minutes) were analyzed. The care of cicadelid nymphs ranged between 12 and 961 seconds.
Laser-Assisted Removal of Aspirated Thumbtacks by Flexible Bronchoscopy
Authors: Fruchter Oren , Fox Benjamin D. , Raviv Yael , Kramer Mordechai R.
Published: June 2010

Background. Aspirated thumbtacks are difficult to extract as the sharp edge of the thumbtack often is well imbedded within bronchial wall and its removal is technically demanding and may cause complications such as bronchial mucosal tear and bronchial wall perforation. These sharp metal objects are commonly removed using rigid bronchoscopy since their removal through flexible bronchoscopy is considered to be dangerous.
Objectives. To describe a technique for removal of sharp aspirated metal objects employing laser through flexible bronchoscopy. Methods. We report two patients in whom a new technique for removal of sharp aspirated metal objects utilizing Nd-Yag laser flexible bronchoscopy was used. Results. Successful and uncomplicated removal of the aspirated thumbpack by flexible bronchoscopy under conscious sedation was accomplished in the two patients described. Both patients were discharged within 24 hours. Conclusions. In patients with aspirated thumbtack laser-assisted breakage of the object through flexible bronchoscopy may obviate the need for rigid bronchoscopy or thoracotomy.
Sensitivity with Respect to the Path Parameters and Nonlinear Stiffness of Vibration Transfer Path Systems
Authors: Zhang Yimin , Huang Xianzhen
Published: June 2010

Generally speaking, a vibration system consists of three parts: vibration resource, vibration transfer path, and vibration receiver. Based on the dynamic sensitivity technique, this paper proposes a method for evaluating the contribution of each vibration transfer path to the dynamic response of the vibration receiver. Nonlinear stiffness is an important factor in causing the nonlinearity of vibration systems. Taking sensitivity as the evaluation criteria, we present an effective approach for estimating the influence of nonlinear stiffness in vibration transfer paths on the dynamic response of the vibration receiver. Using the proposed method, the sensitivity of the vibration system with multiple and/or multidimensional transfer paths could be determined in the time domain.
Regulation of ENaC-Mediated Sodium Reabsorption by Peroxisome Proliferator-Activated Receptors
Authors: Pavlov Tengis S. , Imig John D. , Staruschenko Alexander
Published: June 2010

Peroxisome proliferator-activated receptors (PPARs) are members of a steroid hormone receptor superfamily that responds to changes in lipid and glucose homeostasis. Peroxisomal proliferator-activated receptor subtypeγ(PPARγ) has received much attention as the target for antidiabetic drugs, as well as its role in responding to endogenous compounds such as prostaglandinJ2. However, thiazolidinediones (TZDs), the synthetic agonists of the PPARγare tightly associated with fluid retention and edema, as potentially serious side effects. The epithelial sodium channel (ENaC) represents the rate limiting step for sodium absorption in the renal collecting duct. Consequently, ENaC is a central effector impacting systemic blood volume and pressure. The role of PPARγagonists on ENaC activity remains controversial. While PPARγagonists were shown to stimulate ENaC-mediated renal salt absorption, probably via Serum- and Glucocorticoid-Regulated Kinase 1 (SGK1), other studies reported that PPARγagonist-induced fluid retention is independent of ENaC activity. The current paper provides new insights into the control and function of ENaC and ENaC-mediated sodium transport as well as several other epithelial channels/transporters by PPARs and particularly PPARγ. The potential contribution of arachidonic acid (AA) metabolites in PPAR-dependent mechanisms is also discussed.
Acute Myocardial Infarction due to Coronary Artery Embolism in a Patient with Mechanical Aortic Valve Prosthesis
Authors: Nakazone Marcelo A. , Tavares Bruno G. , Machado Maurício N. , Maia Lilia N.
Published: June 2010

Previous cases of coronary embolism as a cause of myocardial infarction (MI) in association with prosthetic mechanical valves have been reported, but the fact that the patient was not aware of the importance of maintaining anticoagulation therapy is relevant in this case. A 16-year-old female was referred for primary coronary intervention due to subacute anterolateral ST elevation MI, after she decided to discontinue warfarin therapy three weeks before. Coronary angiography showed distal occlusion of the left anterior descending coronary artery with an image suggesting embolic material. Conventional echocardiography demonstrated akinesia of anteroseptal, inferior, and posterior segments of the left ventricle, with severe systolic dysfunction, beyond the intraventricular thrombus. The presence of mechanic aortic prosthesis and no anticoagulation therapy are highly suggestive of coronary embolism as the cause of MI. This case report confirms that patient education is vital in our struggle to prevent this complication in high-risk patients.
Non‐Gaussianity from Large‐Scale Structure Surveys
Authors: Verde Licia
Published: June 2010

With the advent of galaxy surveys which provide large samples of galaxies or galaxy clusters over a volume comparable to the horizon size (SDSS‐III,
HETDEX, Euclid, JDEM, LSST, Pan‐STARRS, CIP, etc.) or mass‐selected large
cluster samples over a large fraction of the extra‐galactic sky (Planck, SPT, ACT,
CMBPol, B‐Pol), it is timely to investigate what constraints these surveys can
impose on primordial non‐Gaussianity. I illustrate here three different
approaches: higher‐order correlations of the three dimensional galaxy
distribution, abundance of rare objects (extrema of the density distribution), and
the large‐scale clustering of halos (peaks of the density distribution). Each of
these avenues has its own advantages, but, more importantly, these approaches
are highly complementary under many respects.
The Role of Immediate Recurrent Laryngeal Nerve Reconstruction for Thyroid Cancer Surgery
Authors: Sanuki Tetsuji , Yumoto Eiji , Minoda Ryosei , Kodama Narihiro
Published: June 2010

Unilateral vocal fold paralysis (UVFP) is one of the most serious problems in conducting surgery for thyroid cancer. Different treatments are available for the management of UVFP including intracordal injection, type I thyroplasty, arytenoid adduction, and laryngeal reinnervations. The effects of immediate recurrent laryngeal nerve (RLN) reconstruction during thyroid cancer surgery with or without UVFP before the surgery were evaluated with videostroboscopic, aerodynamic, and perceptual analyses. All subjects experienced postoperative improvements in voice quality. Particularly, aerodynamic analysis showed that the values for all patients entered normal ranges in both patients with and without UVFP before surgery. Immediate RLN reconstruction has the potential to restore a normal or near-normal voice by returning thyroarytenoid muscle tone and bulk seen with vocal fold denervation. Immediate RLN reconstruction is an efficient and effective approach to the management of RLN resection during surgery for thyroid cancer.
Modulation of Adult Mesenchymal Stem Cells Activity by Toll-Like Receptors: Implications on Therapeutic Potential
Authors: DelaRosa Olga , Lombardo Eleuterio
Published: June 2010

Mesenchymal stem cells (MSCs) are of special interest as therapeutic agents in the settings of both chronic inflammatory and autoimmune diseases. Toll-like receptors (TLR) ligands have been linked with the perpetuation of inflammation in a number of chronic inflammatory diseases due to the permanent exposure of the immune system to TLR-specific stimuli. Therefore, MSCs employed in therapy can be potentially exposed to TLR ligands, which may modulate MSC therapeutic potential in vivo. Recent results demonstrate that MSCs are activated by TLR ligands leading to modulation of the differentiation, migration, proliferation, survival, and immunosuppression capacities. However inconsistent results among authors have been reported suggesting that the source of MSCs, TLR stimuli employed or culture conditions play a role. Notably, activation by TLR ligands has not been reported to modulate the “immunoprivileged” phenotype of MSCs which is of special relevance regarding the use of allogeneic MSC-based therapies. In this review, we discuss the available data on the modulation of MSCs activity through TLR signalling.
Disabled Peers and Academic Achievement
Authors: Friesen Jane , Hickey Ross , Krauth Brian
Published: June 2010

We use data on students in grades 4–7 in the Canadian province of British Columbia to investigate the effect of having disabled peers on value-added exam outcomes. Longitudinal data for multiple cohorts of students are used together with school-by-grade-level fixed effects to account for endogenous selection into schools. Our estimates suggest that same-grade peers with learning and behavioral disabilities have an adverse effect on the test score gains of nondisabled students in British Columbia. However, these effects are statistically insignificant and are sufficiently small that they are unlikely to raise concerns about the placement of this group of disabled students. The effect of peers with other disabilities is also small and statistically insignificant but varies in sign.
Comments on “A Surrogate Ensemble Study of Climate Reconstruction Methods: Stochasticity and Robustness”
Authors: Rutherford Scott D. , Mann Michael E. , Ammann Caspar M. , Wahl Eugene R.
Published: June 2010

In a recent paper, Christiansen et al. compared climate reconstruction methods using surrogate ensembles from a coupled general circulation model and pseudoproxies. Their results using the regularized expectation maximization method with truncated total least squares (RegEM-TTLS) appear inconsistent with previous studies. Results presented here show that the poor performance of RegEM-TTLS in Christiansen et al. is due to 1) their use of the nonhybrid method compared to the hybrid method; 2) a stagnation tolerance that is too large and does not permit the solution to stabilize, which is compounded in another paper by Christiansen et al. by the introduction of an inappropriate measure of stagnation; and 3) their use of a truncation parameter that is too large. Thus, the poor performance of RegEM-TTLS in both Christiansen et al. papers is due to poor implementation of the method rather than to shortcomings inherent to the method.
Trust in Governance Networks
Authors: Klijn Erik-Hans , Edelenbos Jurian , Steijn Bram
Published: June 2010

Governance networks are characterized by complex interaction and decision making, and much uncertainty. Surprisingly, there is very little research on the impact of trust in achieving results in governance networks. This article asks two questions: (a) Does trust influence the outcomes of environmental projects? and (b) Does active network management improve the level of trust in networks? The study is based on a Web-based survey of respondents involved in environmental projects. The results indicate that trust does matter for perceived outcomes and that network management strategies enhance the level of trust.
Alignment and Results
Authors: Meier Kenneth J. , O’Toole Laurence J. , Boyne George A. , Walker Richard M. , Andrews Rhys
Published: June 2010

Theory and evidence has grown on the role of strategy in public organizations. Miles and Snow suggest that strategy’s impact on organizational success will be greatest when external and internal factors are in alignment—when, for instance, managerial prospectors in decentralized organizations operate in a turbulent environment. This study examines three of the Miles and Snow factors—strategy, structure, and the environment—with an appropriate set of statistical tests in several hundred public organizations over a 6-year period. The results suggest that at least for this set of organizations, the contingency relationships proposed by Miles and Snow do not hold.
Is Time Spent With the Physician Associated With Parent Dissatisfaction Due to Long Waiting Times?
Authors: Feddock Christopher A. , Bailey Paula D. , Griffith Charles H. , Lineberry Michelle J. , Wilson John F.
Published: June 2010

The objectives of this study were to assess the relationship between wait time and parent satisfaction and determine whether time with the physician potentially moderated any observed negative effects of long wait time. Data were collected from parents in a pediatric outpatient clinic. Parent satisfaction with the clinic visit was significantly negatively related to wait times. More time spent with the physician was positively related to satisfaction independent of wait times. Furthermore, among clinic visits with long wait times, more time with the physician showed a relatively strong positive relationship with parent satisfaction. Therefore, although long wait times was related to decreased parent satisfaction with pediatric clinic visits, increased time with the physician tended to moderate this relationship.
Towards a European identity? The news media and the case of climate change
Authors: Olausson Ulrika
Published: June 2010

Much research on the discursive construction of Europe in national news media has quantitatively focused on the presence of ‘EU topics’. The more frequently EU topics appear, the better the breeding-ground for a sense of European community, it is argued. This article tackles the question of a European identity from a different angle. Guided by theories on collective identity and power, and utilizing qualitative discourse analysis of the reporting on climate change in a tabloid newspaper and public service television news in Sweden, this article discerns a budding European political identity, discursively embedded and ‘hidden’ in the reporting as the natural order of things. When turned into common-sense knowledge, the European realm as a representative of ‘Us’ is accorded spontaneous legitimacy as a relevant political power in the making of meaning on climate change.
The value of emotion: An examination of television journalists’ notions on emotionality
Authors: Pantti Mervi
Published: June 2010

This article engages with current discussions about public emotions by examining journalists’ perceptions of the value of emotional expression in broadcast news. First, the study provides insight into how journalists assess the place and role of emotion in news reporting and the perceived emotionalizing of news. Second, it examines how the journalists’ discourse about emotion is linked to their ideas of ‘good journalism’, as well as to their professional self-image. The data consist of in-depth interviews with television journalists working for both public service and commercial news programmes in Finland and in the Netherlands.
Marking journalistic independence: Official dominance and the rule of product substitution in Swedish press coverage
Authors: Shehata Adam
Published: June 2010

Independence and autonomy from political power are core values among professional journalists in most western societies. At the same time, research has shown that news media organizations rely heavily on official actors for the construction of news. The purpose of this study is to analyse the nature of official dominance and manifestations of news media independence strategies in routine political press coverage in Sweden. Building upon past research on official dominance, objectivity rituals, indexing and the rule of product substitution — a set of hypotheses is derived and tested using a content analysis of 835 news stories published in Dagens Nyheter and Svenska Dagbladet during a 15-week period in 2008. While official actors dominate news coverage both in terms of source use and story initiation, evidence for a rule of product substitution is found.
Educating Parents: Public Preschools and Parenting in Soviet Pedagogical Publications, 1945-1989
Authors: Gradskova Yulia
Published: June 2010

This article explores the role preschools played in state politics aimed at the family in Soviet Russia. The study is inspired by Foucault’s theory on governmentality and is based on an analysis of Doshkolnoe vospitanie, the largest Soviet magazine on preschool education. This article shows that Soviet children were analyzed scientifically and that parents in Soviet Russia were not freed from the responsibilities of bringing up and educating their children. The central function of preschools was to remind the parents of their responsibilities and to control their performance of them.
The Inertia of Sex: Henry Adams on Family and the Politics of Unconditional Love
Authors: Duff Brian
Published: June 2010

This article offers a reassessment of the contemporary relevance of the political thought of Henry Adams through a focus on his ideas about the relationship between family and politics. Adams’ ideas have been dismissed by contemporary thinkers, like Richard Rorty, who rely on similar ideas about the role family should play in politics. The article traces the role of ideas about family as a unifying theme in Adam’s history, fiction, and autobiography. It shows both why Adams believed familial sentiments, especially feminine and motherly love, were crucial to political unity, and why he thought these sentiments had become increasingly difficult to rely upon. In showing how Adams wrestled with the difficulties that emerge in putting familial sentiments to use for politics, the article suggests that Adams’ ideas offer useful lessons for contemporary thinkers interested in the relationship between family and politics.
Writing Material in Chemical Physics Research: The Laboratory Notebook as Locus of Technical and Textual Integration
Authors: Wickman Chad
Published: June 2010

This article, drawing on ethnographic study in a chemical physics research facility, explores how notebooks are used and produced in the conduct of laboratory science. Data include written field notes of laboratory activity; visual documentation of in situ writing processes; analysis of inscriptions, texts, and material artifacts produced in the laboratory and assembled in notebooks; and an in-depth interview with an expert chemist whose research and writing formed the basis of this investigation. Findings from this study suggest that the notebook occupies a negotiated space between the scientist’s contingent response to exigency in the laboratory and the genre-specific strategies that he or she deploys to communicate his or her work outside the laboratory. This text, the author argues, might therefore be understood as a locus in the sense that it facilitates a reflexive process whereby inscriptions are used both to interpret a-perceptual chemical phenomena in time, and, through their inclusion and integration in the notebook, to discipline that interpretation over time. Tracing the way inscriptions move between material synthesis, on the one hand, and text production, on the other, this article ultimately offers a methodical approach for investigating how the material, technical, and symbolic dimensions of writing and text converge in a modern scientific workplace.
Development of a Novel Cell Encapsulation System Based on Natural Origin Polymers for Tissue Engineering Applications
Authors: Luna S.M. , Gomes M.E. , Mano J.F. , Reis R.L.
Published: June 2010

Cells microencapsulated in biocompatible semi-permeable polymeric membranes are effective as cell delivery systems while protecting the host against immune responses. In this study, cell encapsulation membranes were prepared based on carrageenan and alginate, two natural cationic polymers. Different formulations/conditions were explored to optimize the microcapsules which were characterized with respect to their morphology, mechanical stability, and cytotoxicity. Spherical-shaped microcapsules were obtained from all the polymeric systems. The iota-carrageenan/sodium alginate microcapsules exhibited the best stability and permeability, and therefore, these were selected for the cell encapsulation. These capsules provided an environment that supported cell proliferation and have the potential for tissue engineering as well as other cell-based therapy applications.
Oversulfated Heparin By-Products Induce Thrombin Generation in Human Plasmas Through Contact System Activation
Authors: Yi Qian  , Jing Pan  , Xiaodong Zhou  , Hourcade Dennis E. , Liszewski M. Kathryn , Atkinson John P. , Hong Lu  , Lijuan Zhang
Published: June 2010

Thrombin generation is thought to be mediated predominantly by the tissue factor or ‘‘extrinsic’’ coagulation pathway. An alternate pathway to thrombin generation (the ‘‘intrinsic’’ pathway or contact system) has been observed when blood or plasma comes in contact with artificial surfaces. Here we present evidence for a new route to thrombin formation that begins with the activation of the contact system protein prekallikrein by oversulfated heparin (OS-HB). Kallikrein, instead of activated factor X, cleaves prothrombin to form thrombin. Thrombin then cleaves fibrinogen to form fibrin clots. Moreover, we show that OS-HB by-products induce kallikrein- and thrombin-like activities in normal human plasma and in human plasma devoid of coagulation factor X or downstream contact system components factor IX or factor XI. Oversulfated heparin by-product-induced thrombin generation may have had a role in the adverse reactions associated with the recent clinical use of contaminated heparin.
Now you don’t see it; now you do
Authors: Mitchell Sally
Published: June 2010

This article was given as a keynote address to the 2009 conference of the European Association for the Teaching of Academic Writing (EATAW), 30 June to 2 July, at Coventry University, UK. It draws on experiences at Queen Mary, University of London, of developing a ‘writing in the disciplines’ initiative and of working towards institutional recognition for writing as a key and integral part of student learning. It raises issues about the transition from school to university writing and about such frameworks as ‘Graduate Attributes’. Sometimes weaving together others’ stories, it argues that, whilst there is great potential for writing development in universities, we also need to be aware of risks that derive from adopting industrialized approaches, governed by a narrow emphasis on form, belief in the possibility and benefits of ‘transparency’ and an over-reliance on explicit criteria to drive assessment and learning.
Optimizing Blown Film Line Layouts for Improved Surface Treating Performance
Authors: Gilbertson Tom , Leonardelli Mario , Wolf Rory
Published: June 2010

Blown film processors, large and small, have limited resources in both capital and manpower to devote to optimizing their productivity. Yet avenues of improvement are open for even the most over-extended organization. And some of the most effective modifications cost little more than a small change in equipment orientation or procedures. A key aspect of optimizing a blown film layout is line footprint and determining how to minimize footprint and maximize output with each integral piece of equipment on the line. Multiple surface treatment systems are integral to every blown film line and can control product quality and line efficiencies. The objective of this work is to present best practices of blown film manufacturers ranging from multinationals to small privately owned operations relative to the most effective surface treatment system designs, their roll coverings, optimum power density settings, alternative treatment technologies, troubleshooting protocols, and model line layouts that optimize production output.
Structure Determination of H-LDS: An Acidified Form of the Layered Silicate K-LDS
Authors: Ikeda Takuji , Uenaka Manami , Komura Kenichi , Sugi Yoshihiro
Published: June 2010

The crystal structure of H-LDS (Si8O20H8)—an acidified form of the layered silicate K-LDS—was determined. Structure analysis from X-ray powder diffraction data shows that its layer structure comprises a six-membered Si atom ring network. 1H MAS NMR spectroscopy indicates strong intra- and interlayer hydrogen bonding between neighboring terminal oxygen atoms. Electron density distributions attributed to hydrogen bonding are obtained by the maximum entropy method. The structure of H-LDS is stabilized by the hydrogen bonds without an alkali metal cation.
Indium(III)-catalyzed Coupling between Alkynes and Aldehydes to α,β-Unsaturated Ketones
Authors: Miura Katsukiyo , Yamamoto Kiyomi , Yamanobe Aya , Ito Keisuke , Kinoshita Hidenori , Ichikawa Junji , Hosomi Akira
Published: June 2010

The combined use of a catalytic amount of InX3 (X = OTf and NTf2) and 1-butanol was found to be effective in formal alkyne–aldehyde metathesis. With this catalytic system, aromatic alkynes reacted with aromatic aldehydes to give chalcones in moderate to good yields. Alkynals were efficiently converted into 5- to 7-membered cyclic compounds by intramolecular alkyne–aldehyde coupling.
Change, Consolidation, and Competition in Health Care Markets
Authors: Gaynor Martin , Haas-Wilson Deborah
Published: June 2010

In this paper, the authors summarize the nature of the changes in the structure of the health-care industry. They focus on the markets for health insurance, hospital services, and physician services. They discuss the potential implications of the restructuring of the health care industry for competition, efficiency, and public policy. As will become apparent, this area offers a number of intriguing questions.
The Familiar but Curious Economics of Higher Education: Introduction to a Symposium
Authors: Clotfelter Charles T
Published: June 2010

Despite the involvement of two-thirds of economists in it, the higher education industry remains incompletely understood. Among the topics related to higher education that invite further research are the rapid increase in college costs, the interaction of tenure and the end of mandatory retirement, and the effects of college enrollment on income inequality. Data from surveys of freshmen suggests that the gap in socioeconomic status between students in private universities and other young people has grown over time.
Adam Smith Goes to College: An Economist Becomes an Academic Administrator
Authors: Ehrenberg Ronald G
Published: June 2010

The author asks whether it is useful to view universities in a utility-maximizing framework and shows that university organizing virtually guarantees that the utility-maximizing model is the incorrect approach. He then discusses resource allocation issues at Cornell and reflects upon how concepts that are obvious to economists helped or hindered decision making at Cornell. The author hopes to convey not that economic concepts are irrelevant in operating a university, but rather that it takes a long time to explain to all the actors in the system why these concepts should matter and even longer to actually make them matter.
The Economist in Tort Litigation
Authors: Thornton Robert , Ward John
Published: June 2010

In recent decades, the involvement of economists as consultants and expert witnesses in civil tort actions has grown rapidly. In this article, the authors discuss the reasons for this phenomenon and the extent to conflicts of interest to arise in the practice of what is frequently called ‘forensic economics.’ They argue that, although conflict-of-interest pressures exist, the limited evidence does not indicate that unethical practices are rampant within the profession. Moreover, market correctives, judicial screening, codes of ethical behavior, and the dissemination of knowledge concerning proper forensic practice help to serve as (arguably imperfect) safeguards against unethical practice.
Three Sides of Harberger Triangles
Authors: Hines James R
Published: June 2010

Harberger triangles are used to calculate the efficiency costs of taxes, government regulations, monopolistic practices, and various other market distortions. This paper considers the historical development of Harberger triangles, the associated theoretical controversies, and the contribution of Harberger triangles to subsequent empirical work and theories of market imperfections. Prior to the publication of Arnold Harberger's papers, economists very rarely estimated deadweight losses. The empirical deadweight loss literature expanded greatly since the 1960s, making such estimation now quite common. Meanwhile, critical evaluation of deadweight loss estimates led to new theories of rent-seeking and other inefficiencies of economies with multiple distortions.
Business Cycles in International Historical Perspective
Authors: Basu Susanto , Taylor Alan M
Published: June 2010

This paper examines business cycles theoretically and empirically, with a quantitative study based on data for a cross section of countries. Theoretical concerns indicate that the properties of business cycle models depend not only on important structural aspects of the model, such as money neutrality, labor market structure, and price adjustment, but also on the closure of the model in international markets. Econometric considerations suggest that panel data can provide more information about the country-specific versus universal features of cycles. The authors review business cycle properties in a sample of over a dozen counties in light of these issues.
Policy Watch: The Marriage Penalty
Authors: Alm James , Dickert-Conlin Stacy , Whittington Leslie A
Published: June 2010

Many government programs have implicit penalties or subsidies for marriage. For example, many couples pay higher income taxes when married than their combined tax liabilities as single filers, while many other couples receive a marriage subsidy because their joint taxes fall with marriage. Likewise, most low-income couples are eligible for higher welfare benefits if they are separated rather than married. This article discusses the marriage penalty, with a particular focus on tax and transfer programs. Why does it exist? Who faces it? To what extent does it affect marriage and labor market behavior? What tradeoffs are involved in reducing it?
Why Has Africa Grown Slowly?
Authors: Collier Paul , Gunning Jan Willem
Published: June 2010

We distinguish between policy and “destiny” explanations of Africa's slow growth during the past three decades. Policies were poor: high export taxation and inefficient public service delivery, and “destiny” was adverse: landlocked, tropical locations, and terms of trade deterioration. During the 1990s, Africa's economic policies improved, although with considerable variation both between countries and between policies: trade and exchange rate policies improved much more than service delivery. Thus, the differing explanations of past slow growth imply different predictions for growth in the coming decade. We argue that poor public economic services are likely to be the binding constraint.
Health and Schooling Investments in Africa
Authors: Schultz T. Paul
Published: June 2010

Intercountry comparisons show Africa's health and education falls short of other regions, controlling for income, women's educations, and urbanization, but growth regressions do not clarify whether this low human capital caused slow growth. Microeconometric estimates of wage returns to schooling and health indicate relatively attractive private returns in several sub-Saharan countries, although data are severely limited. Biases due to household heterogeneity and selection into the sample of wage earners do not appear to alter these assessments that the quantity and quality of human capital investments will affect future economic growth in Africa and its more equitable distribution.
Survey Measures of Expected U.S. Inflation
Authors: Thomas Lloyd B
Published: June 2010

The forecasting performance of widely accessible surveys of expected inflation are evaluated against naive and financial market benchmark forecasts. In the period of rising inflation (1960-80), the Michigan household consensus forecasts exhibited smaller errors than the Livingston Survey of economists and the benchmark forecasts. Unlike Livingston, the Michigan forecasts were unbiased. Since 1980, Livingston forecasts have been more accurate than Michigan, though unbiasedness is rejected in both cases. SPF forecasts, available since 1981, have been slightly superior to Livingston. In forecasting inflation, respondents generally failed to take account of cyclical conditions, and strong-form rationality is not supported.
Measuring Returns on Investments in Collectibles
Authors: Burton Benjamin J , Jacobsen Joyce P
Published: June 2010

This paper considers the question of how to measure and interpret the financial return to investing in collectibles. We review various methodologies for creating priced indexes and then discuss studies that explicitly calculate a rate of return to some set of collectibles. While most collectibles appear to yield positive real returns, the majority embody more risk and yield lower financial returns than stocks. Other characteristics of collectibles prices, such as covariance with other asset prices, are also examined.
In Honor of the Nobel Laureates Robert C. Merton and Myron S. Scholes: A Partial Differential Equation That Changed the World
Authors: Jarrow Robert A
Published: June 2010

The Nobel Prize was given to Robert C. Merton and Myron S. Scholes for discovering a new method for determining the value of an option. This is known as the Black-Merton-Scholes option pricing formula. The purpose of this essay is to explain why the Black-Merton-Scholes option pricing formula is so important to the finance profession, the economics profession, the financial industry, and society at large. This is done by studying the history of the formula's development, the economic logic underlying the formula's derivation, and the formula's ramifications for the various professions.
Restoring Banking Stability: Beyond Supervised Capital Requirements
Authors: Caprio Gerard , Honohan Patrick
Published: June 2010

Emerging economies have been particularly prone to financial sector crises, reflecting marked information asymmetries and political interference, as well as the substantial volatility in underlying economic conditions, and the vulnerability of banking and finance when structural economic changes create a new and uncharted operating environment. The standard regulatory paradigm relies mainly on supervised capital adequacy, but it may not be enough. Other measures to improve the incentive structure for bankers, regulators, and other market participants could effectively increase the number of concerned, skilled and watchful eyes. Intermittent application of supplementary “blunt instruments” could also be useful.
On the Need for an International Lender of Last Resort
Authors: Fischer Stanley
Published: June 2010

Is there a useful function for an international lender of last resort (ILLR)--defined as crisis lender and crisis manager? Yes for international capital flows are excessively volatile and contagious, and because an ILLR can help mitigate the effects of this instability. I examine the Bagehot rules, and their applicability in an international context, focusing on the problem of moral hazard. I argue that a critical condition for the successful operation of an ILLR, a role that is to an important extent played by the IMF, is to ensure private sector involvement in the resolution of emerging market financial crises.