bluuebunny/crossref_metadata_2025 huggingface dataset:
Metal–Metal Bonded Diruthenium Unit Axial-Capped by Di-tert-butylphenolate: [Ru2(O2CCH3)2(t-Busal-R′py)2]− (t-Busal-R′py2− = N-(R′-2-pyridyl)-2-oxido-3,5-di-tert-butylbenzylaminato; R′ = H, 4-Me, and 5-Me)
Authors: Miyasaka Hitoshi , Izawa Toru , Takaishi Shinya , Sugimoto Kunihisa , Sugiura Ken-ichi , Yamashita Masahiro
Published: April 2006

Three diruthenium compounds, [Na(18-crown-6)(thf)2][Ru2(O2CCH3)2(t-Busalpy)2] (1), [K(18-crown-6)(thf)2][Ru2(O2CCH3)2(t-Busal-4-Mepy)2], (2), and [K(18-crown-6)(thf)(H2O)][K(18-crown-6)(thf)(MeO)][Ru2(O2CCH3)2(t-Busal-5-Mepy)2] (3) (18-crown-6 = 1,4,7,10,13,16-hexaoxocyclooctadecane; 18-crown-6-ether), have been synthesized by the ligand substitution reaction of Ru2(O2CCH3)4Cl with newly prepared tridentate bridging/chelating ligands, N-(2-pyridyl)-2-oxido-3,5-di-tert-butylbenzylaminato (t-Busalpy2−), N-(4-methyl-2-pyridyl)-2-oxido-3,5-di-tert-butylbenzylaminato (t-Busal-4-Mepy2−), and N-(5-methyl-2-pyridyl)-2-oxido-3,5-di-tert-butylbenzylaminato (t-Busal-5-Mepy2−), respectively, and isolated using [Na(18-crown-6)]+ or [K(18-crown-6)]+ as the counter cation. The structural features of the anionic parts are very similar to those of the previously synthesized family of [Ru2(O2CCH3)2(5-Rsalpy)2]− (R = H, Me, Cl, Br, and NO2); two acetate and two t-Busal-R′py2− ligands are respectively located around the Ru2 unit in a trans fashion, where the t-Busal-R′py2− ligand acts as a tridentate ligand having both bridging and chelating characters to form the M–M bridging/axial-chelating mode. Their Ru–Ru bonded core with an electronic configuration of σ2π4δ2(π*δ*)3 is axial-capped by the di-t-butylphenolate groups of the t-Busal-R′py2− ligands, and experiences multi-redox properties: a one-electron reduction to Ru24+ and two one-electron oxidations to Ru26+ followed by Ru27+, in addition to t-Busal-R′py2− ligand-centered redox. The strong electron-donating ability of the t-butyl groups compared with the other R-groups leads to negative shifts of the redox potentials according to the Hammett law.
One-Step Synthesis of a Platinum Nanoparticle with Carbon Materials Using a Phenylazomethine Dendrimer as a Template
Authors: Enoki Osamu , Imaoka Takane , Yamamoto Kimihisa
Published: April 2006

A phenylazomethine dendrimer was developed for the one-step preparation of a platinum nanoparticle–carbon nanocomposite. The dendrimer formed a complex with platinum tetrachloride (PtCl4) in a chloroform–acetonitrile mixed solvent. The coordination behavior between the dendrimer and the platinum salts was confirmed by UV–vis and 1H NMR titration experiments. The obtained dendrimer–PtCl4 complexes were pyrolyzed under a nitrogen atmosphere at 1000 °C, and converted to spherical and dispersed platinum nanoparticles on a pyrolytic graphite identified by transmission electron microscopy (TEM). A high resolution TEM (HR-TEM) image of the products showed some lattice fringes attributed to the presence of Pt(111) in the particles, and X-ray photoelectron spectra (XPS) of the products corresponded to those of Pt(0). These results indicated that PtCl4 was perfectly converted to metallic platinum through this pyrolysis condition. Raman spectra showed that the dendrimer remained as an amorphous carbon after pyrolysis. The electrode modified with the product showed a catalytic activity for dioxygen reduction, which electrochemically confirmed that part of the carbon was porous enough to let the substrate go through and to reach the platinum surface.
Two New Halogenated Briarane Diterpenes from the Papuan Gorgonian Coral Junceella fragilis
Authors: K. Kubota Natsuki , Kobayashi Yuka , Iwamoto Hajime , Fukazawa Yoshimasa , Uchio Yasuto
Published: April 2006

Two new halogenated briarane diterpenes, (−)-2-deacetyljunceellin (1) and (−)-3-deacetyljunceellin (2), and five known diterpenoids, junceellin, praelolide, junceellolide A, B, and D were isolated from the Papuan gorgonian coral Junceella fragilis. The structures of the new metabolites were determined by extensive 2D NMR experiments and by chemical conversion. The absolute configuration of 2 was determined through the 1H NMR study of the corresponding ester with a newly developed chiral auxiliary 3a.
Effect of Boron Addition on the Intrinsic Activity of Al2O3-Supported Cobalt–Tungsten and Cobalt–Molybdenum Sulfide Catalysts for the Hydrodesulfurization of Thiophene
Authors: Usman  , Kubota Takeshi , Okamoto Yasuaki
Published: April 2006

The effect of boron addition was studied on the intrinsic activity of Al2O3-supported cobalt–molybdenum and cobalt–tungsten sulfide catalysts prepared by a CVD technique using [Co(CO)3NO] as a precursor of Co. The catalysts were characterized by means of NO adsorption and Raman spectroscopy. The intrinsic activity of the catalysts are discussed in terms of the turnover frequency (TOF) of the hydrodesulfurization of thiophene, calculated on the basis of the amount of the Co–Mo(W)–S phase. The intrinsic activity on the Co–Mo–S phase and the Co–W–S phase was increased by the addition of boron in a different way depending on the presulfidation temperature. The addition of a proper amount of boron weakened the interactions between molybdenum (tungsten) oxides and the Al2O3 surface, leading to an increase in the TOF on the Co–Mo–S phase and the Co–W–S phase by a factor of 1.6 and 1.3, respectively, when Mo(W)S2/Al2O3 was presulfided at 673 K. As for the catalyst presulfided at 773 K, the addition of boron increased the TOF on both CVD-Co/MoS2/B/Al2O3 and CVD-Co/WS2/B/Al2O3 by a factor of 1.9. A reverse correlation was observed between the strength of the molybdenum (tungsten) oxides–Al2O3 interactions and the intrinsic activity on the Co–Mo(W)–S phase.
Hydrotalcite-Derived Mg/Al Mixed Oxides as Support Materials for the Friedel–Crafts Catalyst ZnCl2
Authors: Shimada Hiroshi , Nishimura Naohisa
Published: April 2006

ZnCl2 supported on Mg/Al mixed oxides obtained through the thermal decomposition of hydrotalcite showed high catalytic activity in the benzylation of benzene with benzyl chloride at room temperature. The surface properties of hydrotalcite-derived mixed oxides suggested that they increased the catalytic activities of ZnCl2 owing to their high mesoporosity, with pore sizes in the vicinity of 10 nm.
CUG-BP binds to RNA substrates and recruits PARN deadenylase
Authors: Moraes Karen C.M. , Wilusz Carol J. , Wilusz Jeffrey
Published: April 2006

CUG-BP is the human homolog of the Xenopus EDEN-BP, which was shown previously to bind to mRNAs, such as c-mos, that exhibit rapid deadenylation following fertilization of the oocyte. While several studies have focused on roles of CUG-BP as a splicing or translation regulator in mammalian cells, its role in mRNA decay has not been examined in detail. Here, we have used an in vitro deadenylation assay to dissect the function of CUG-BP in the decay of two ARE-containing mRNAs: c-fos and TNFα. CUG-BP binds specifically to both of these RNAs and stimulates poly(A) shortening by PARN. Moreover, CUG-BP interacts with PARN in extracts by coimmunoprecipitation, and this interaction can be recapitulated using recombinant proteins. CUG-BP, therefore, is the first RNA-binding protein shown to directly recruit a deadenylase to an RNA substrate.
Reference Intervals for Hemoglobin A1c in Pregnant Women: Data from an Italian Multicenter Study
Authors: Mosca Andrea , Paleari Renata , Dalfrà Maria G , Di Cianni Graziano , Cuccuru Ilaria , Pellegrini Giovanni , Malloggi Lucia , Bonomo Matteo , Granata Simona , Ceriotti Ferruccio , Castiglioni Maria T , Songini Marco , Tocco Giuliana , Masin Michela , Plebani Mario , Lapolla Annunziata
Published: April 2006

Background: The reference intervals for hemoglobin A1c (Hb A1c) in pregnant women without diabetes are not well defined, and few examples of reference intervals established by networks of different laboratories are available.

Methods: Five Italian Diabetic Care Units were involved in the study. Data were collected from 445 pregnant women without diabetes, selected on the basis of glucose challenge test results, and from 384 nonpregnant control women. The Hb A1c measurements were performed with HPLC systems aligned to the Diabetes Control and Complications Trial. Plasma glucose measurements were also performed locally. Both Hb A1c and glucose measurements were harmonized by running appropriate external quality assessment schemes. The reference intervals were calculated in terms of nonparametric 2.5th to 97.5th percentiles with 0.90 confidence intervals.

Results: The Hb A1c measurements were reproducible (CV = 2.0%) and accurate [mean (SE) difference from the target values, −0.10 (0.06)%]. Glucose measurements were also reproducible (mean CV = 3.2%) and accurate [difference from the target values, −0.01 (0.04) mmol/L]. To calculate common reference intervals, we merged the data collected in the different centers. The Hb A1c reference intervals were 4.0%–5.5% for pregnant nondiabetic women and 4.8%–6.2% for nonpregnant controls.

Conclusions: Healthy pregnant women have lower Hb A1c concentrations than nonpregnant women. The reference intervals for Hb A1c in pregnant women should therefore be lower than those currently in use.
Do Slotting Allowances Enhance Efficiency or Hinder Competition?
Authors: Sudhir K. , Rao Vithala R.
Published: April 2006

Slotting allowances are lump-sum payments by manufacturers to retailers for stocking new products. The economic rationale for slotting allowances is controversial. Supporters argue that slotting allowances are efficiency enhancing; critics argue that they are anticompetitive. However, there is no empirical research on this issue because of the difficulty in obtaining data about these transactions. Using data on all new products that were offered to one retailer for a period of nine months, the authors empirically investigate support for the alternative rationales for slotting allowances. The analysis indicates that, in general, there is more support for the efficiency theories than for the anticompetitive theories. The authors find that slotting allowances (1) efficiently allocate scarce retail shelf space, (2) help balance the risk of new product failure between manufacturers and retailers, (3) help manufacturers signal private information about potential success of new products, and (4) widen retail distribution for manufacturers by mitigating retail competition. The authors find little support for the anticompetitive rationales in the data. The empirical support for the efficiency rationales suggests that the Federal Trade Commission was correct in being circumspect about banning slotting allowances outright.
Price Matching by Vertically Differentiated Retailers: Theory and Evidence
Authors: Moorthy Sridhar , Zhang Xubing
Published: April 2006

This research examines vertically differentiated retailers' incentives to offer price-matching guarantees. It suggests that offering and not offering a price-matching guarantee are both signals of a retailer's service-price profile, a way of branding the retailer to uninformed consumers. The signals are made credible and costless by the presence of informed consumers. The authors show that when the service differentiation is large enough, only low-service retailers offer price-matching guarantees. Data from a sample of Canadian retail chains support this prediction. In addition, larger retail chains are more likely to offer price-matching guarantees than smaller chains, and competition has an interactive effect with service. As the intensity of competition a chain faces increases, lower-service retailers are even more likely to use a guarantee, and higher-service retailers are less likely to do so, suggesting that price-matching guarantees are competitive tools, not collusive tools, as the literature has often implied.
Factors Affecting Web Site Visit Duration: A Cross-Domain Analysis
Authors: Danaher Peter J. , Mullarkey Guy W. , Essegaier Skander
Published: April 2006

In this study, the authors examine factors that affect Web site visit duration, including user demographics, text and graphics content, type of site, presence of functionality features, advertising content, and the number of previous visits. The authors use a random effects model to determine the impact of these factors on site duration and the number of pages viewed. The proposed method accounts for three distinct sources of heterogeneity that arise from differences among people, Web sites, and visit occasions to the same Web site by the same person. The model is fit using one month of user-centric panel data, and it encompasses the 50 most popular sites in a market. The results show that, in general, older people and women visit Web sites for a longer period. Some surprising results are revealed in an examination of interactions between these demographic and site characteristic variables. For example, sites with higher levels of advertising usually result in lower visit duration, but this is not the case for older people. The model also yields insights into the relative importance of different sources of heterogeneity in visit duration; heterogeneity in visit occasions dominates over individual-level and Web site-specific heterogeneity.
Customer Acquisition Promotions and Customer Asset Value
Authors: Lewis Michael
Published: April 2006

In this article, the author addresses the question of how a firm's acquisition efforts influence the composition of the customer portfolio. The first part of the research is a conceptual model that illustrates how customer uncertainty provides an explanation for why promotionally acquired customers have lower repurchase rates and smaller lifetime values. The second part of the research involves empirical analyses of customer-level data from a newspaper and an online grocer. In both data sets, acquisition discount depth is negatively related to repeat-buying rates and customer asset value. For example, a 35% acquisition discount results in customers with about one-half the long-term value of non-promotionally acquired customers.
Paying Too Much and Being Happy about It: Existence, Causes, and Consequences of Tariff-Choice Biases
Authors: Lambrecht Anja , Skiera Bernd
Published: April 2006

A common assumption underlying the analysis of consumers' choices among optional tariffs is that consumers choose the tariff that maximizes their surplus and, thus, the tariff that leads to the lowest billing rate for a given amount of usage. Yet there is evidence that many users prefer a flat rate even though their billing rate would be lower with a pay-per-use tariff (flat-rate bias), and some users prefer a pay-per-use tariff even though they would save money with a flat rate (pay-per-use bias). The authors conduct four empirical analyses based on three different data sets. They show that the flat-rate bias is more important and has a greater regularity and time persistence than the pay-per-use bias. They classify potential causes of the flat-rate bias as “insurance effect,” “taxi meter effect,” “convenience effect,” and “overestimation effect” and show that the insurance, the taxi meter, and the overestimation effects lead to a flat-rate bias. They provide evidence that underestimation of usage is a major cause of the pay-per-use bias. They show that the flat-rate bias does not significantly increase customer churn and thus results in a short- and long-term profit increase. In contrast, the pay-per-use bias largely increases churn so that in the long run, the additional short-term profit is offset by higher churn.
The Impact of Standards Competition on Consumers: Effectiveness of Product Information and Advertising Formats
Authors: Chakravarti Amitav , Xie Jinhong
Published: April 2006

Compared with other markets, those with competing technological standards exhibit certain fundamental characteristics that make a consumer's decision to adopt a new product more risky and more complex. This article examines how standards competition affects consumer behavior, an issue that has been relatively neglected by previous research in this area. The results show that consumers depend on different types of information in their adoption decisions and respond differently to advertising. Specifically, the authors find that standards competition motivates consumers to pay more attention to information that is comparative in nature. Thus, information about the relative (absolute) performance of a product has a stronger (weaker) impact on a product's share in markets with standards competition (Study 1). Standards competition also moderates the effectiveness of different advertising formats: It strengthens the effect of comparative advertisements but weakens the effect of noncomparative advertisements (Study 2). As a result, two commonly observed drawbacks of comparative advertisements—negative attitude toward the ad and source confusion—disappear in the presence of standards competition (Study 2), and comparative advertisements even induce greater confidence in the advertised brand (Study 3). Finally, in the presence of standards competition, the superiority of comparative advertisements is stronger when the advertised brand has a disadvantage in terms of brand familiarity than when it has an advantage (Study 3). This research takes a step toward a better understanding of these important but underexplored issues and provides managerial insights for firms that launch new products in markets with competing standards.
A Feature-Based Approach to Assessing Advertisement Similarity
Authors: Schweidel David A. , Bradlow Eric T. , Williams Patti
Published: April 2006

This research presents a feature-based statistical model and subsequently explores the degree to which similarity perceptions between two advertisements can be decomposed and explained by a “weighted-and-summed” distance measure, computed on the advertisements' executional elements, after controlling for familiarity and viewers' attitudinal responses toward the advertisements. Furthermore, the authors obtain empirical findings in two major areas: First, variation in similarity ratings can be explained by the advertisements' features, a finding of potential importance for advertisement construction. Second, some, but not all, executional elements that have been shown (in the literature) to drive recall and persuasion are effective at driving perceptions of similarity. This is of practical importance because managers want their advertisements not only to be liked and remembered but also (possibly) to be perceived as similar (or dissimilar) to those for other products. In particular, an understanding of which items drive which constructs (recall and persuasion, or similarity) can contribute to a more effective overall marketing strategy.
Action-Based Learning: Goals and Attention in the Acquisition of Market Knowledge
Authors: Eisenstein Eric M. , Hutchinson J. Wesley
Published: April 2006

In this article, the authors examine the costs and benefits of action-based learning (i.e., learning that occurs as a by-product of making repeated decisions with outcome feedback). The authors report the results of three experiments that investigate the effects of different decision goals on what is learned and how transferable that learning is across related decision tasks. Contrary to popular wisdom, compared with traditional learning, experiential learning is likely to be a risky proposition because it can be either accurate and efficient or errorful and biased.
Licensing Effect in Consumer Choice
Authors: Khan Uzma , Dhar Ravi
Published: April 2006

Most choices in the real world follow other choices or judgments. The authors show that a prior choice, which activates and boosts a positive self-concept, subsequently licenses the choice of a more self-indulgent option. The authors propose that licensing can operate by committing to a virtuous act in a preceding choice, which reduces negative self-attributions associated with the purchase of relative luxuries. Five studies demonstrate the proposed licensing effect of a prior commitment to a virtuous act on subsequent choice. Consistent with the authors' theory, the preference for an indulgent option diminishes if the licensing task is attributed to an external motivation. The authors also report a mediation analysis in support of their theoretical explanation that the licensing effect operates by providing a temporary boost in the relevant self-concept.
Monetary Incentives and Mood
Authors: Meloy Margaret G. , Russo J. Edward , Miller Elizabeth Gelfand
Published: April 2006

Researchers have long debated the methodological necessity of monetary incentives in experimental research. The current work shows that financial incentives not only can fail to improve task performance but also can worsen it. Three studies verify that incentives can elevate mood and that this mood enhancement contributes to worsened task performance. The authors discuss implications for the use of incentives in experimental research.
An Empirical Investigation of Signaling in the Motion Picture Industry
Authors: Basuroy Suman , Desai Kalpesh Kaushik , Talukdar Debabrata
Published: April 2006

The contribution of this research lies in the use of real-world data to test several hypotheses about the role of two signals—sequels and advertising expenditures—in the motion picture industry. The authors analyze the data with a dynamic simultaneous-equations model of the drivers and the interrelationships of the behaviors of movie audiences, studios, and exhibitors. Specifically, the authors test for the attenuating role of third-party information sources, such as critics' review consensus and cumulative word of mouth, on the strength of the two aforementioned signals. The authors find evidence of such an effect both at the release phase across movies and over the postrelease phase for any movie. Notably, they hypothesize and show that sequels and advertising expenditures have a positive interaction effect on box office revenues. This is an important finding because though most firms use multiple signals for their products, empirical work on the interaction of two or more signals is rare. This study offers several new and interesting empirical insights into the market dynamics of the motion picture industry.
Aligning Innovation with Market Characteristics in the Nonprofit Professional Theater Industry
Authors: Voss Glenn B. , Montoya-Weiss Mitzi , Voss Zannie Giraud
Published: April 2006

In this study, the authors integrate theories of innovation diffusion, relational exchange behavior, and organizational learning to explain the roles of innovation, product exploration experience, promotion, and market sophistication in determining firm performance. They test the research questions using objective measures of financial performance from a sample of 124 firms in the nonprofit professional theater industry. The results suggest that the independent variables interact in systematic ways to influence firm performance across two different customer segments: relational and transactional. The findings lend empirical support to two theoretical perspectives that have received little prior empirical examination: (1) Innovation performance is determined by characteristics of the overall marketplace and target market segments, and (2) product exploration experience enhances organizational learning and performance.
Preanalytical variability: the dark side of the moon in laboratory testing
Authors: Lippi Giuseppe , Guidi Gian Cesare , Mattiuzzi Camilla , Plebani Mario
Published: April 2006

Remarkable advances in instrument technology, automation and computer science have greatly simplified many aspects of previously tedious tasks in laboratory diagnostics, creating a greater volume of routine work, and significantly improving the quality of results of laboratory testing. Following the development and successful implementation of high-quality analytical standards, analytical errors are no longer the main factor influencing the reliability and clinical utilization of laboratory diagnostics. Therefore, additional sources of variation in the entire laboratory testing process should become the focus for further and necessary quality improvements. Errors occurring within the extra-analytical phases are still the prevailing source of concern. Accordingly, lack of standardized procedures for sample collection, including patient preparation, specimen acquisition, handling and storage, account for up to 93% of the errors currently encountered within the entire diagnostic process. The profound awareness that complete elimination of laboratory testing errors is unrealistic, especially those relating to extra-analytical phases that are harder to control, highlights the importance of good laboratory practice and compliance with the new accreditation standards, which encompass the adoption of suitable strategies for error prevention, tracking and reduction, including process redesign, the use of extra-analytical specifications and improved communication among caregivers.
The Case for Scotch Beef
Authors: Wilson Ron
Published: April 2006

The beef industry in Scotland is at a cross-road. It will need to become more market-responsive to survive. This presentation examines some of the basic characteristics of the industry, considers the current barriers to change and asks whether PGI quality status can be helpful in the transformation.
Unusual High Exposure to Ultraviolet‐C Radiation
Authors: Trevisan Andrea , Piovesan Stefano , Leonardi Andrea , Bertocco Matteo , Nicolosi Piergiorgio , Pelizzo Maria Guglielmina , Angelini Annalisa
Published: April 2006

?1 UV radiation is known to cause acute and chronic eye and skin damage. The present case report describes a 90 min accidental exposure to UV‐C radiation of 26 medical school students. Germicidal lamps were lit due to a malfunctioning of the timer system. Several hours after irradiation exposure, all subjects reported the onset of ocular symptoms, subsequently diagnosed as photokeratitis, and skin damage to the face, scalp and neck. While the ocular symptoms lasted 2–4 days, the sunburn‐like condition produced significant erythema followed by deep skin exfoliation. The irradiation was calculated to be approximately 700 mJ cm−2 absorbed energy, whereas the actual radiation emitted by the lamps was 0.14 mW cm−2 (the radiometric measurements confirmed these calculi, because the effective irradiance measured from the height of the autopsy table to about 1 m under the UV‐C lamp varied from 0.05 to 0.25 mW cm−2) but, more likely, the effective irradiance, according to skin phototype and symptoms, was between 50 and 100 mJ cm−2. The ocular and skin effects produced by such a high irradiation (largely higher than that accepted by the American Conference of Governmental Industrial Hygienists [ACGIH] threshold limit values [TLVs]) appeared reversible in a relatively short time.
Enhancement of Osseointegration by Generating a Dynamic Implant Surface
Authors: Anitua Eduardo A.
Published: April 2006

Preparations of autologous plasma rich in growth factors (PRGF) are used to promote healing and tissue regeneration. We seek to determine whether covering the titanium implant surface with this preparation could enhance osseointegration. The interaction of PRGF with the surface of titanium implants was examined by environmental scanning electron microscopy (ESEM). A total of 23 implants were placed in the tibiae and radii of 3 goats; 13 implants were inserted after covering the surface and filling the alveolus with PRGF, and 10 more implants were inserted following a conventional protocol and served as controls. Histomorphometric analysis of the bone-implant interface was performed after 8 weeks. Finally, 1391 implants were placed in 295 patients after bioactivating the surface with PRGF. Stability and implant survival were evaluated. The implant surface adsorbed the protein-rich material as shown by ESEM. In the animal study, osseointegration was enhanced when the surface was covered with PRGF as shown by histomorphometry (bone-implant contact: 51.28% ± 4.7% vs 21.89% ± 7.36%; P < .01). Finally, studies in patients showed that 99.6% of the implants treated with PRGF were well osseointegrated. Clinical use of this technique in oral implantology can improve the prognosis.
The Role of Interfacial Mechanics in the Prediction of Global Mechanical Behavior of a Bioactive Composite: An In Vitro Study
Authors: Ho Emily , Marcolongo Michele
Published: April 2006

A bioactive bone-tissue substitute, hydroxyapatite (HA)-polymethylmethacrylate (PMMA) with the addition of a copolymer coupling agent, was examined in vitro to determine the influence of the coupling agent on the local mechanical properties of the system before and after simulated biologic conditions. Nano-indentation of the cross-sectional interface between the HA and PMMA of the composite was studied. The fracture mechanism and position of each indent mark were analyzed at up to 5000× magnification under field-emission, environmental-scanning electron microscopy. The local interfacial results were compared with global quasistatic compression test results. It was found that nano-indentation of the interface could predict changes in global mechanical behavior of the composite. Both interfacial and global Young's moduli were reduced after immersion in the simulated biologic media. Although the coupling agent improved the interfacial and global mechanical properties before and after 24 hours in in vitro immersion, it did not affect the surface bioactivity of the system, as shown in the measurement of calcium and phosphate concentration uptake. Thus, nano-indentation is a sensitive technique for examining interfacial mechanics and mechanical consequences of biologic reactivity of composite materials.
Cone Beam Computerized Tomography-based Dental Imaging for Implant Planning and Surgical Guidance, Part 1: Single Implant in the Mandibular Molar Region
Authors: Almog Dov M. , LaMar James , LaMar Frank R. , LaMar Frank
Published: April 2006

Computerized tomography (CT)-based dental imaging for implant planning and surgical guidance carries both restorative information for implant positioning, as far as trajectory and distribution, and radiographic information, as far as depth and proximity to critical anatomic landmarks such as the mandibular canal, maxillary sinus, and adjacent teeth. This case report describes a systematic approach to the planning and surgical placement of a single implant-supported crown, utilizing CT-based dental imaging for implant planning and surgical guidance. The simple steps result in the accurate transfer of critical radiographic information to the surgical site.
Institutional Origins of Unemployment Compensation: An Empirical Analysis of the Developing World, 1946–2000
Authors: Kim Wonik
Published: April 2006

Why do some countries institutionalize a social program compensating the unemployed while others do not? My main argument is that the choice to have an unemployment insurance program is a function of 1) the distribution of unemployment risks within a country and 2) political processes through which demands for insurance are realized. The distribution of industrial-specific risks and workers' employment status are the driving force in shaping workers' demands. In developing countries, these demands are more likely to be realized under democratic regimes. An event history model for 102 developing countries from 1946 to 2000 is used to test the arguments.
Increased Risk-Bearing with Background Risk
Authors: Gollier Christian , Schlee Edward E
Published: April 2006

Analyses of risk-bearing often assume that agents face only one risk. Agents however usually face several risks and the interaction between them can affect the willingness to bear any one of them. We consider how the introduction of background risk affects the comparative statics predictions of distribution changes in the standard two asset portfolio model. We show that such predictions are fairly robust, no matter what the correlation between the two risks. We consider changes in the conditional distributions of the risky asset's return; and changes in the marginal distribution of the asset's return. For the first question, a version of Gollier's (1995) Central Riskiness order is sufficient and necessary to increase risk-bearing. For the second question, Monotone Likelihood Ratio improvements are sufficient and necessary. Many of our proofs illustrate the "basis" approach to comparative statics under uncertainty.
Quantitative Monetary Easing and Risk in Financial Asset Markets
Authors: Kimura Takeshi , Small David H.
Published: April 2006

In this paper, we empirically examine the portfolio-rebalancing effects stemming from the policy of “quantitative monetary easing” recently undertaken by the Bank of Japan when the nominal short-term interest rate was virtually at zero. Portfolio-rebalancing effects resulting from the open market purchase of long-term government bonds under this policy have been statistically significant. Our results also show that the portfolio-rebalancing effects were beneficial in that they reduced risk premiums on assets with counter-cyclical returns, such as government and high-grade corporate bonds. But, they may have generated the adverse effects of increasing risk premiums on assets with pro-cyclical returns, such as equities and low-grade corporate bonds. These results are consistent with a CAPM framework in which business-cycle risk importantly affects risk premiums. Our estimates capture only some of the effects of quantitative easing and thus do not imply that the complete set of effects were adverse on net for Japan’s economy. However, our analysis counsels caution in accepting the view that, ceteris paribus, a massive large-scale purchase of long-term government bonds by a central bank provides unambiguously positive net benefits to financial markets at zero short-term interest rates.
Treatment of Cork Wastes in a Conical Spouted Bed Reactor
Authors: San Jose Maria J , Alvarez Sonia , Ortiz de Salazar Alvaro , Morales Alberto , Bilbao Javier
Published: April 2006

The applicability of conical spouted bed reactors for the treatment of cork caps has been studied by means of a hydrodynamic study with homogeneous beds of cork of different size in different experimental conditions. The validity of the ranges of the geometric factors of the contactor and of the contactor-particle system for stable spouting established in previous papers and of the equation for the calculation of the minimum spouting velocity proposed for granular materials and glass spheres has been proven for beds consisting of cork. The suitable design of the conical spouted bed reactor for the combustion of cork wastes requires the previous knowledge of the ranges of the geometric factors of the contactor and of the contactor-particle system for stable spouting.
Letter: Has Becker Put Economics in the Electric Chair?
Authors: Johnes Geraint
Published: April 2006

According to Geraint Johnes, a key element of Gary Becker's argument for capital punishment undermines much of economics as we know it.
Optimal Power Flow Solution: a GA-Fuzzy System Approach
Authors: Saini Ashish , Chaturvedi Devendra K. , Saxena A. K.
Published: April 2006

Optimal power flow (OPF) is one of the nonlinear problems of power system. The various algorithms for solving optimal power flow problem are found in the literature. The genetic algorithm (GA) based solution techniques are found to be most suitable because of their ability of simultaneous multidimensional search for optimal solution. This paper presents a novel GA-Fuzzy based approach for solving OPF. The GA parameters e.g. crossover and mutation probabilities are governed by fuzzy rule base. Algorithms for GA-OPF and GA-Fuzzy (GAF) OPF are developed and compared. The results obtained for these systems demonstrate that the GAF-OPF has faster convergence and lesser generation costs as compared to various methods tested for above systems.
Application of Loop Frame of Reference to Power Flow Tracing and Loss Allocation
Authors: Lim Valerie S.C. , McDonald John D.F. , Saha Tapan K.
Published: April 2006

This paper introduces a new power flow tracing and subsequently loss allocation method based on loop analysis. The knowledge of the loop paths aids in the visualisation of presumed transfer of power throughout the transmission network. A formalised process of loop identification, based on graph theory, is introduced to ensure that each loop contains at least one active source. This way, the system losses can be readily and justifiably allocated to the active sources in the network without involving any approximations. The proposed method is applied to both a small test system and the IEEE 14-bus test system, demonstrating the features and limitations of the proposed methodology.
The Effect of Malpractice Liability on the Delivery of Health Care
Authors: Baicker Katherine , Chandra Amitabh
Published: April 2006

The growth of medical malpractice liability costs has the potential to affect the delivery of health care in the U.S. along two dimensions. If growth in malpractice payments results in higher malpractice insurance premiums for physicians, these premiums may affect the size and composition of the physician workforce. The growth of potential losses from malpractice liability might also encourage physicians to practice defensive medicine. We use rich new data to examine the relationship between the growth of malpractice costs and the delivery of health care along both of these dimensions. We pose three questions. First, are increases in payments responsible for increases in medical malpractice premiums? Second, do increases in malpractice liability drive physicians to close their practices or not move to areas with high payments? Third, do increases in malpractice liability change the way medicine is practiced by increasing the use of certain procedures? First, we find that increases in malpractice payments made on behalf of physicians do not seem to be the driving force behind increases in premiums. Second, increases in malpractice costs (both premiums overall and the subcomponent factors) do not seem to affect the overall size of the physician workforce, although they may deter marginal entry, increase marginal exit, and reduce the rural physician workforce. Third, there is little evidence of increased use of many treatments in response to malpractice liability at the state level, although there may be some increase in screening procedures such as mammography.
Comparing the Quality of Health Care Providers
Authors: McClellan Mark , Staiger Douglas
Published: April 2006

This article introduces a new approach for evaluating the quality of healthcare providers, including an integrated solution to several problems that limit the usefulness of available methods. Our approach combines information from all the quality indicators available for a provider (e.g., from other years, other patients, or other indicators for the same patients) to estimate more accurately the providers previous or expected quality. The approach also provides an empirical basis for comparing and combining alternative quality indicators, thereby enabling policy makers to choose among potential indicators, explore the potential bias in alternative measures, and increase the value of quality measures for assessing and improving care. Using hospital care for elderly heart attack patients as an example, we demonstrate that these methods can be used to create reliable, precise predictions about provider quality. Comparing quality of care across providers may be far more feasible than many now believe.
Tutorial on protein fingerprinting
Authors: Levander Fredrik
Published: April 2006

Protein fingerprinting using mass spectrometry is an efficient technique for protein identification. In this tutorial an overview of the process is given and factors that have influence on the success rate are discussed.
Topology of protein interaction networks and cell physiology
Authors: Marsolier‐Kergoat Marie‐Claude
Published: April 2006

The first descriptions of large protein interaction networks have revealed unexpected topological properties that have been linked to various aspects of cell physiology. In this paper are reviewed the proposed connections between local or global features of protein networks and biological parameters like protein essentiality or mutational robustness.
Cover Picture: Hierarchy Selection, Position Control, and Orientation of Growing Mesostructures by Patterned Surfaces (Adv. Mater. 8/2006)
Authors: Khalil A. S. G. , Konjhodzic D. , Marlow F.
Published: April 2006

Spontaneous hierarchical organization of silica by means of a command surface is shown on the cover and described on p. 1055 by Marlow and co‐workers. In this approach, the usual co‐existence of energetically similar structures is overcome, permitting selection of one hierarchical silica structure. A patterned substrate is shown to lead to pixel‐like, simultaneous growth of a hierarchal assembly involving four structural levels. The individual pixels belong to a new class of circularly organized solids.
Estimation of agitator flow shear rate
Authors: Wu Jie , Graham Lachlan J. , Noui Mehidi Nabil
Published: April 2006

Laboratory laser Doppler velocimetry (LDV) measurements were conducted to measure the shear rate coefficient KS of a range of impellers. Equations correlating KS with NQ (flow number) are provided for axial flow and radial flow impellers. Theoretical formulations based on the classic boundary layer theory are developed to estimate the shear rate at the blade surface. Calculations show that the shear rates at the blade surface are many orders of magnitude higher than those in the flow at the impeller outlet. The software code XFOIL was used to illustrate typical distributions of the shear rates along the blade surfaces. Effects of viscosity, non‐Newtonian shear‐thinning index, agitator design, and scale‐up on shear rates are illustrated. © 2006 American Institute of Chemical Engineers AIChE J, 2006
The place of serials in referencing practices: Comparing natural sciences and engineering with social sciences and humanities
Authors: Larivière Vincent , Archambault Éric , Gingras Yves , Vignola‐Gagné Étienne
Published: April 2006

Journal articles constitute the core documents for the diffusion of knowledge in the natural sciences. It has been argued that the same is not true for the social sciences and humanities where knowledge is more often disseminated in monographs that are not indexed in the journal‐based databases used for bibliometric analysis. Previous studies have made only partial assessments of the role played by both serials and other types of literature. The importance of journal literature in the various scientific fields has therefore not been systematically characterized. The authors address this issue by providing a systematic measurement of the role played by journal literature in the building of knowledge in both the natural sciences and engineering and the social sciences and humanities. Using citation data from the CD‐ROM versions of the Science Citation Index (SCI), Social Science Citation Index (SSCI), and Arts and Humanities Citation Index (AHCI) databases from 1981 to 2000 (Thomson ISI, Philadelphia, PA), the authors quantify the share of citations to both serials and other types of literature. Variations in time and between fields are also analyzed. The results show that journal literature is increasingly important in the natural and social sciences, but that its role in the humanities is stagnant and has even tended to diminish slightly in the 1990s. Journal literature accounts for less than 50% of the citations in several disciplines of the social sciences and humanities; hence, special care should be used when using bibliometric indicators that rely only on journal literature.
Multiple authorship in a small medical journal: A case study of the Croatian Medical Journal
Authors: Ivanišević Ranka , Sapunar Damir
Published: April 2006

The authors assess the number of coauthors in articles published by authors affiliated with domestic (Croatian) and foreign (non‐Croatian) institutions in the Croatian Medical Journal (CMJ) and investigate the increase in the number of coauthors after inclusion of the journal in the Current Contents (CC) bibliographic database (Thomson ISI, Philadelphia, PA) in 1999. They analyzed 761 articles published in the CMJ between 1992 and 2003, and determined the average number of authors per article, authors' country of origin, and the gross domestic product (GDP) per capita of the authors' country. The average number of authors in articles written by authors affiliated with domestic institutions was significantly larger in almost all journal sections. The increase in the number of domestic coauthors was more pronounced after inclusion of the journal in the CC database. The number of domestic coauthors published in the Clinical section increased from 4.2 ± 2.1 to 5.1 ± 2.3. There was also an increase in coauthors published in the Public Health section—from 3.1 ± 1.9 to 4.1 ± 1.9. The results of the study imply that authors' adherence to the International Committee of Medical Journal Editors (ICMJE) authorship criteria depends on the size of the scientific community and that adherence is poor among domestic authors publishing in a small, national medical journal outside of mainstream science. An increased number of coauthors in articles published by authors affiliated with domestic institutions does not necessarily imply authorship misconduct but it suggests involvement of an appreciable number of authors who made few or no substantial contributions to the research. This discounts two main purposes of scientific authorship: to confer credit and denote responsibility for performed research.
Superquenching as a detector for microsphere‐based flow cytometric assays
Authors: Zeineldin Reema , Piyasena Menake E. , Bergstedt Troy S. , Sklar Larry A. , Whitten David , Lopez Gabriel P.
Published: April 2006

Background:

Fluorescent conjugated polymers display high fluorescence quantum yields and enhanced sensitivity to quenching (superquenching) by oppositely charged quenchers through energy or electron transfer. Fluorescent polymers and their quenchers are used in bead‐based biosensor applications where the polymers are coated on particles. In this work, we investigate a detection method that utilizes superquenching on microspheres, which can be used for flow cytometric assays.

Methods:

Microspheres were coated with the fluorescent cationic polyelectrolyte poly(p‐phenylene‐ethynylene) (PPE), and its superquenching by 9,10‐anthraquinone‐2,6‐disulfonic acid (AQS) was examined by fluorometric methods in presence and in absence of a barrier to superquenching in the form of an anionic lipid bilayer.

Results:

Flow cytometry detected superquenching of PPE on microspheres (MS‐PPE) by AQS where high levels of reduction in fluorescence were observed. Adding different concentrations of AQS to MS‐PPE yielded a Stern–Volmer quenching constant of 0.8 × 106 M−1. While forming an anionic lipid bilayer around the MS‐PPE acted as a barrier to superquenching by AQS, disrupting the lipid bilayer allowed superquenching to take place.

Conclusions:

The sensitivity of flow cytometry in detecting fluorescence of microspheres and the amplified quenching sensitivity of fluorescent conjugated polymers both offer advantages over other fluorometric methods and conventional quenching detection. This study used superquenching of fluorescent polymers as a new tool in flow cytometry, thus combining the advantages offered by both method and detector. In addition, we employed the formation and the disruption of a supported lipid bilayer in mediating superquenching to offer new biosensing applications. © 2006 International Society for Analytical Cytology