bluuebunny/crossref_metadata_2025 huggingface dataset:
TERRITORIAL CAPITAL AND REGIONAL GROWTH: INCREASING RETURNS IN KNOWLEDGE USE
Authors: CAPELLO ROBERTA , CARAGLIU ANDREA , NIJKAMP PETER
Published: September 2010

Knowledge drives the growth of nations and regions in a competitive space‐economy. Hence, we would expect a strong correlation between investments in R&D, knowledge and learning processes, on the one hand, and productivity increases, on the other. However, the empirical evidence shows consistent discrepancies between knowledge inputs and economic performance across geographical units. This paper addresses this intriguing issue at the regional level, by highlighting theoretically and empirically the strategic importance played by intangible elements as part of “territorial capital” in mediating between knowledge production and regional growth. The main proposition of the paper, subject to empirical testing, is that intangible elements as part of territorial capital magnify the contribution of knowledge by determining the formation of increasing returns to knowledge exploitation.
GROUNDING THEORIES OF PLACE AND GLOBALISATION
Authors: ANTONSICH MARCO
Published: September 2010

In the 1990s, under the perception of increasing transformations brought about by globalisation, scholars started investigating what happened to the notion of place. Among others, the views of Manuel Castells, Robert Sack and Doreen Massey contributed to construct an opposition between a parochial, bounded, and reactionary notion of place versus a global, unbounded, and relation one. This latter view, under the label of ‘progressive sense of place’, has since become a dominant paradigm in geography. This paper aims to ground these theoretical arguments in relation to how people understand place today. Qualitative empirical information collected in four different regional contexts in Western Europe confirms the discursive existence of the above opposition. Yet, it also challenges the ways in which notions of thickness/thinness and boundedness/unboundedness relate to the regressive or progressive character of place.
SCALE, AGGLOMERATION, AND REGIONAL INEQUALITY IN PROVINCIAL CHINA
Authors: WEI YEHUA DENNIS , YU DANLIN , CHEN XIAOJING
Published: September 2010

This study analyses regional development in provincial China through a case study of Jiangsu following the multi‐scale and multi‐mechanism framework. We have revealed a trend of increasing regional inequality and find it is mainly a result of the rapid development of Sunan (Southern Jiangsu), which also results in rising rural inter‐county inequality. Subei (northern Jiangsu) faces more challenges due to the strong effects of self‐reinforcing agglomeration and the constraints of geographical barriers. The spatial Markov chain analysis reveals that the development status of neighbouring counties has a strong influence on a county's development dynamics; a poor county neighbouring relatively richer counties has a higher possibility to move upwards, and vice versa. The geographically weighted regression analysis reveals that development mechanisms have strong local characteristics and the same mechanism affects regional development differently. Finally, our study confirms that the multi‐scale and multi‐mechanism framework helps the understanding of regional development in Jiangsu.
RESOURCE CURSE, POLITICAL ENTRY, AND DEADWEIGHT COSTS
Authors: TSUI KEVIN K.
Published: September 2010

A simple model of political entry in a two‐sector economy is developed to analyze the effects of natural resource wealth on economic policy, political development, and civil insurrection. The model emphasizes the role of political entry and deadweight costs of taxation on the joint determination of these economic and political outcomes. Contrary to popular belief, my model shows that natural resource abundance is an economic blessing even in a rent‐seeking society, although resource dependence can be negatively associated with economic performance. In a contested political market, dictators care about popular support and hence resource wealth can help reduce the deadweight cost of taxation (and hence the cost of public good provision). On the other hand, natural resource wealth can be a political curse, because it encourages political entry and hence it induces incumbent dictators to run more repressive regimes. With constant returns counterinsurgent technology, however, the equilibrium number of insurgents is independent of the size of resource wealth. The onset of civil war, therefore, depends on the counterinsurgent technology and whether the costs of entry deterrence are affected by resource wealth. This helps clarify the two seemingly contradictory hypotheses that “resource wealth enhances regime durability” and “resource wealth fuels conflict.”
RATE‐CUTTING TAX REFORMS AND CORPORATE TAX COMPETITION IN EUROPE
Authors: HEINEMANN FRIEDRICH , OVERESCH MICHAEL , RINCKE JOHANNES
Published: September 2010

While there is a large and growing number of studies on the determinants of corporate tax rates, the literature has so far ignored the fact that the behavior of governments in setting tax rates is often best described as a discrete choice decision problem. We set up an empirical model that relates a government's decision whether to cut its corporate tax rate to the country's own inherited tax and taxes in neighboring countries. Using comprehensive data on corporate tax reforms in Europe since 1980, we find evidence suggesting that the position in terms of the tax burden imposed on corporate income relative to geographical neighbors strongly affects the probability of rate‐cutting tax reforms. Countries are particularly likely to cut their statutory tax rate if the inherited tax is high and if they are exposed to low‐tax neighbors.
Screening for tumours in paraneoplastic syndromes: report of an EFNS Task Force
Authors: Titulaer M. J. , Soffietti R. , Dalmau J. , Gilhus N. E. , Giometto B. , Graus F. , Grisold W. , Honnorat J. , Sillevis Smitt P. A. E. , Tanasescu R. , Vedeler C. A. , Voltz R. , Verschuuren J. J. G. M.
Published: September 2010

Background:  Paraneoplastic neurological syndromes (PNS) almost invariably predate detection of the malignancy. Screening for tumours is important in PNS as the tumour directly affects prognosis and treatment and should be performed as soon as possible.

Objectives:  An overview of the screening of tumours related to classical PNS is given. Small cell lung cancer, thymoma, breast cancer, ovarian carcinoma and teratoma and testicular tumours are described in relation to paraneoplastic limbic encephalitis, subacute sensory neuronopathy, subacute autonomic neuropathy, paraneoplastic cerebellar degeneration, paraneoplastic opsoclonus‐myoclonus, Lambert‐Eaton myasthenic syndrome (LEMS), myasthenia gravis and paraneoplastic peripheral nerve hyperexcitability.

Methods:  Many studies with class IV evidence were available; one study reached level III evidence. No evidence‐based recommendations grade A–C were possible, but good practice points were agreed by consensus.

Recommendations:  The nature of antibody, and to a lesser extent the clinical syndrome, determines the risk and type of an underlying malignancy. For screening of the thoracic region, a CT‐thorax is recommended, which if negative is followed by fluorodeoxyglucose‐positron emission tomography (FDG‐PET). Breast cancer is screened for by mammography, followed by MRI. For the pelvic region, ultrasound (US) is the investigation of first choice followed by CT. Dermatomyositis patients should have CT‐thorax/abdomen, US of the pelvic region and mammography in women, US of testes in men under 50 years and colonoscopy in men and women over 50. If primary screening is negative, repeat screening after 3–6 months and screen every 6 months up till 4 years. In LEMS, screening for 2 years is sufficient. In syndromes where only a subgroup of patients have a malignancy, tumour markers have additional value to predict a probable malignancy.
‘What Werre Amounteth’: The Military Experience of Knights of the Shire, 1369–1389
Authors: KING ANDY
Published: September 2010

The Commons in parliament played an increasingly influential role in English politics in the last years of the reign of Edward III, and the reign of his grandson, Richard II. War was the central issue which dominated political debate in parliament. But when they debated war, how many of the knights of the shire knew whereof they spoke? This article discusses the collective military experience of the knights of the shire, assessing their military service in relation to their parliamentary careers. It will look at whether knights of the shire were generally men whose military careers were over or whether they were still militarily active and, in particular, how many of them had recent experience of the doleful record of English failure in the wars since 1369. Finally, it will consider what impact the military experience of knights of the shire had on political debate in parliament and to what degree was the Commons' criticism of the crown's conduct of the wars shaped by the personal military experience of the knights of the shires.
Auditory processing that leads to conscious perception: A unique window to central auditory processing opened by the mismatch negativity and related responses
Authors: Näätänen Risto , Kujala Teija , Winkler István
Published: September 2010

In this review, we will present a model of brain events leading to conscious perception in audition. This represents an updated version of Näätänen's previous model of automatic and attentive central auditory processing. This revised model is mainly based on the mismatch negativity (MMN) and N1 indices of automatic processing, the processing negativity (PN) index of selective attention, and their magnetoencephalographic (MEG) and functional magnetic resonance imaging (fMRI) equivalents. Special attention is paid to determining the neural processes that might underlie conscious perception and the borderline between automatic and attention‐dependent processes in audition.
Are temporal response features prepared in fixed order? Inferences from movement‐related potentials
Authors: Leuthold Hartmut , Jentzsch Ines
Published: September 2010

Using a response precuing task, we investigated whether motor preparation of temporal response features follows a fixed order as implied by the generalized motor program (GMP) view. Relative timing and overall duration of sequential key presses were factorially manipulated. Precues either provided no information, provided partial information about relative or overall duration, or fully specified the response. Reaction time decreased with the amount of advance information, reflecting the reduction of response alternatives by the precue and influences on preparatory motor processes. The contingent negative variation (CNV) over the left but not the medial and right motor regions increased with the amount of advance information provided. The foreperiod lateralized readiness potential indicated hand‐specific activation for the full precue condition only. These findings disagree with the assumption that a GMP's invariant and variable response features are prepared in fixed order.
Approach motivational body postures lean toward left frontal brain activity
Authors: Price Tom F. , Harmon‐Jones Eddie
Published: September 2010

The present experiment examined the effect of different approach motivational body postures on relative left frontal cortical activity, which has been linked with approach motivation. Three body postures were manipulated to create three levels of approach motivation. Consistent with the motivational direction model, results indicated that leaning forward with arms extended (high approach) caused greater left frontal cortical activation as compared to reclining backwards (low approach). This is the first experiment to demonstrate this effect, and it suggests that leaning forward as compared to reclining backward increases approach motivation. These results provide important implications for the motivational direction model and embodiment research.
Aggressive Treatment Style and Surgical Outcomes
Authors: Silber Jeffrey H. , Kaestner Robert , Even‐Shoshan Orit , Wang Yanli , Bressler Laura J.
Published: September 2010

Objective. Aggressive treatment style, as defined by the Dartmouth Atlas of Health Care, has been implicated as an important factor contributing to excessively high medical expenditures. We aimed to determine the association between aggressive treatment style and surgical outcomes.

Data Sources/Study Setting. Medicare admissions to 3,065 hospitals for general, orthopedic, and vascular surgery between 2000 and 2005 (N=4,558,215 unique patients).

Study Design. A retrospective cohort analysis.

Results. For elderly surgical patients, aggressive treatment style was not associated with significantly increased complications, but it was associated with significantly reduced odds of mortality and failure‐to‐rescue. The odds ratio for complications in hospitals at the 75th percentile of aggressive treatment style compared with those at the 25th percentile (a U.S.$10,000 difference) was 1.01 (1.00–1.02), p<.066; whereas the odds of mortality was 0.94 (0.93–0.95), p<.0001; and for failure‐to‐rescue it was 0.93 (0.92–0.94), p<.0001. Analyses that used alternative measures of aggressiveness—hospital days and ICU days—yielded similar results, as did analyses using only low‐variation procedures.

Conclusions. Attempting to reduce aggressive care that is not cost effective is a laudable goal, but policy makers should be aware that there may be improved outcomes associated with patients undergoing surgery in hospitals with a more aggressive treatment style.
The Unintended Consequence of Diabetes Mellitus Pay‐for‐Performance (P4P) Program in Taiwan: Are Patients with More Comorbidities or More Severe Conditions Likely to Be Excluded from the P4P Program?
Authors: Chen Tsung‐Tai , Chung Kuo‐Piao , Lin I‐Chin , Lai Mei‐Shu
Published: September 2010

Objective. Taiwan has instituted a pay‐for‐performance (P4P) program for diabetes mellitus (DM) patients that rewards doctors based in part on outcomes for their DM patients. Doctors are permitted to choose which of their DM patients are included in the P4P program. We test whether seriously ill DM patients are disproportionately excluded from the P4P program.

Data Source/Study Setting. This study utilizes data from the National Health Insurance (NHI) database in Taiwan for the period of January 2007 to December 2007. Our sample includes 146,481 DM‐P4P patients (16.56 percent of the total) and 737,971 non‐DM‐P4P patients.

Data Collection/Extraction Methods. We use logistic and multilevel models to estimate the effects of patient and hospital characteristics on P4P selection.

Principal Findings. The results show that older patients and patients with more comorbidities or more severe conditions are prone to be excluded from P4P programs.

Conclusions. We found that DM patients are disproportionately excluded from P4P programs. Our results point to the importance of mandated participation and risk adjustment measures in P4P programs.
Thromboelastography in healthy horses and horses with inflammatory gastrointestinal disorders and suspected coagulopathies
Authors: Mendez‐Angulo Jose L. , Mudge Margaret C. , Vilar‐Saavedra Paulo , Stingle Nicole , Couto C. Guillermo
Published: September 2010

Objectives –To evaluate the use of citrated recalcified (nonactivated) thromboelastography (TEG) in healthy horses and horses with colitis and suspected coagulopathies.

Design –Prospective, observational study conducted between October 2007 and June 2009.

Setting –Veterinary Teaching Hospital.

Animals –Forty‐five healthy adult horses and 12 sick adult horses with colitis and prolonged prothrombin time (PT) or activated partial thromboplastin time (aPTT).

Interventions –None.

Measurements and Main Results –Whole blood was collected on admission. Coagulation profile (PT, aPTT, platelet count, and fibrinogen concentration) and citrated recalcified whole blood TEG analysis (R‐time [R], K‐time [K], angle [α], maximum amplitude [MA], G value [G], lysis at 60 min [LY60]) were evaluated. Mean values (SD) for TEG parameters in healthy horses were:R=10.4 (3.1) minutes;K=3.5 (1.2) minutes; α=46.3 (11.0)°; MA=55.6 (5.1) mm;G=6,429 (1,341) dyn/cm2, and LY60=5.1 (2.4)%. Mean coefficients of variation for intra‐assay/interindividual variability in healthy horses were:R=4.7%/30.7%,K=4.8%/35.3%, α=4.4%/23.8%, MA=1.4%/9.3%,G=3.4%/20.8%, and LY60=13.1%/47.7%, respectively. Horses with colitis and prolonged PT and/or aPTT had longer mean values forR(P<0.001) andK(P<0.001), narrower mean α (P<0.001), decreased mean MA (P=0.001), and smaller meanG(P=0.02); changes consistent with hypocoagulability.

Conclusions –Citrated recalcified (nonactivated) TEG demonstrated changes consistent with hypocoagulability in horses with colitis that had preidentified coagulation abnormalities. This technique has high interindividual variability and low intra‐assay variability. TEG may be useful for detecting hypocoagulable states in horses with colitis and suspected coagulopathies.
Central and peripheral sites of action for CB2 receptor mediated analgesic activity in chronic inflammatory and neuropathic pain models in rats
Authors: Hsieh Gin C , Pai Madhavi , Chandran Prasant , Hooker Bradley A , Zhu Chang Z , Salyers Anita K , Wensink Erica J , Zhan CenChen , Carroll William A , Dart Michael J , Yao Betty B , Honore Prisca , Meyer Michael D
Published: September 2010

BACKGROUND AND PURPOSE Cannabinoid CB2 receptor activation by selective agonists has been shown to produce analgesic effects in preclinical models of inflammatory and neuropathic pain. However, mechanisms underlying CB2‐mediated analgesic effects remain largely unknown. The present study was conducted to elucidate the CB2 receptor expression in ‘pain relevant’ tissues and the potential sites of action of CB2 agonism in rats.

EXPERIMENTAL APPROACH Expression of cannabinoid receptor mRNA was evaluated by quantitative RT‐PCR in dorsal root ganglia (DRGs), spinal cords, paws and several brain regions of sham, chronic inflammatory pain (CFA) and neuropathic pain (spinal nerve ligation, SNL) rats. The sites of CB2 mediated antinociception were evaluated in vivo following intra‐DRG, intrathecal (i.t.) or intraplantar (i.paw) administration of potent CB2‐selective agonists A‐836339 and AM1241.

KEY RESULTS CB2 receptor gene expression was significantly up‐regulated in DRGs (SNL and CFA), spinal cords (SNL) or paws (CFA) ipsilateral to injury under inflammatory and neuropathic pain conditions. Systemic A‐836339 and AM1241 produced dose‐dependent efficacy in both inflammatory and neuropathic pain models. Local administration of CB2 agonists also produced significant analgesic effects in SNL (intra‐DRG and i.t.) and CFA (intra‐DRG) pain models. In contrast to A‐836339, i.paw administration of AM‐1241 dose‐relatedly reversed the CFA‐induced thermal hyperalgesia, suggesting that different mechanisms may be contributing to its in vivo properties.

CONCLUSIONS AND IMPLICATIONS These results demonstrate that both DRG and spinal cord are important sites contributing to CB2 receptor‐mediated analgesia and that the changes in CB2 receptor expression play a crucial role for the sites of action in regulating pain perception.
Rimonabant reduces keratinocyte viability by induction of apoptosis and exerts topical anti‐inflammatory activity in mice
Authors: Malfitano Anna Maria , Sosa Silvio , Laezza Chiara , De Bortoli Marco , Tubaro Aurelia , Bifulco Maurizio
Published: September 2010

BACKGROUND AND PURPOSEThere is growing evidence that the cannabinoid CB1receptor antagonist, rimonabant (SR141716) exerts potential anti‐proliferative and anti‐inflammatory actions. Here, we have assessed the effects of rimonabantin vitroin murine immortalized keratinocytes andin vivoby assaying the topical anti‐inflammatory activity.

EXPERIMENTAL APPROACHCell viability and death in a keratinocyte cell line (C5N cells) were measured by Trypan blue exclusion assay and cytotoxicity by sulphorhodamine B test. Cell cycle progression was assessed by flow cytometry and the expression of apoptotic and anti‐apoptotic markers, cyclins, pathways of signal transduction and CB1 receptor levels were evaluated by Western blot. The topical anti‐inflammatory properties of rimonabant were analysed by inhibition of croton oil‐induced ear dermatitis in mice.

KEY RESULTSRimonabant reduced cell viability and induced apoptosis as shown by the enhanced number of cells in the subG0 phase of the cell cycle, the expression of Bax and reduced levels of Bcl‐2 and X‐inhibitor of apoptosis protein. In addition, reduced levels of phosphorylated serine/threonine protein kinase Akt and nuclear factor‐kappa B were detected associated with regulation of total nuclear factor‐kappa B and inhibitor of kappa B‐α, phosphorylated inhibitor of kappa B‐α, cyclins D1, E and A. In croton oil‐induced ear dermatitis, rimonabant significantly reduced oedema and leukocyte infiltrate.

CONCLUSIONS AND IMPLICATIONSRimonabant reduced cell viability, inducing cell death in keratinocytes and decreased croton oil‐induced ear dermatitis. Our findings suggest a potential application of rimonabant as a topical anti‐inflammatory drug. We did not assess the involvement of CB1receptors in these effects of rimonabant.
Natural fools and the historiography of Renaissance folly
Authors: Chakravarti Paromita
Published: September 2010

The historiography of Western folly has projected the Renaissance as an age uniquely tolerant of and interested in irrationality, taking the humanist ‘praise of folly’ literature as a marker of this openness. This article problematizes such a representation of Renaissance humanism by exploring the discourse of ‘naturals’ rather than of artificial fools who are at the heart of humanist celebrations of folly. By focussing on legal, medical and New World debates on natural fools, ‘monsters’, wild men, ‘savages’ and natives, this article reveals not just an ambivalence towards fools but also deeper contradictions within Renaissance humanism. The article points out continuities between medieval scholastic, Renaissance humanist and Enlightenment discourses of folly, seeking to provide a caveat against both traditional and Foucaultian historiographies which regard the Renaissance as being singularly hospitable to mental deviance. This article also identifies the persistence of certain tendencies in the discursive practices of folly, finding echoes of Renaissance discussions in later debates in the field of mental disability and the history of psychiatry.
Cryopreservation impact on blood progenitor cells: influence of diagnoses, mobilization treatments, and cell concentration
Authors: Majado Maria J. , Salgado‐Cecilia Gema , Blanquer Miguel , Funes Consuelo , González‐García Consuelo , Insausti Carmen L. , Parrado Antonio , Morales Alfonso , Minguela Alfredo , Moraleda José M.
Published: September 2010

BACKGROUND: The aim of this study was to analyze the impact of cryopreservation in series of peripheral blood progenitor cells stratified by diagnosis, mobilization treatments, and cell concentration, as well as the accuracy of the control aliquots.

STUDY DESIGN AND METHODS: Viability and colony‐forming unit–granulocyte‐macrophage (CFU‐GM), CD34+ cell, lymphocyte, monocyte, and granulocyte counts and recovery were analyzed in 397 leukapheresis procedures before freezing and after thawing. Data from control cryotubes were compared to those from infusing bags.

RESULTS: Cell viability decreased after thawing. Viability recovery was lower in cryotubes than in bags in non‐Hodgkin's lymphoma (NHL), in cyclophosphamide plus granulocyte–colony‐stimulating factor (Cy+G‐CSF) mobilization, and in cell concentration of median or greater. Viability recovery in cryotube was higher in NHL (92.1%) than in Hodgkin's disease (HD; 87.3%) and in G‐CSF (95.9%) than Cy+G‐CSF mobilization (91.3%). The number of CD34+ cells decreased after thawing in total group, Cy+G‐CSF mobilization, and cell concentration less than median subgroups. CD34+ cell recovery was higher in cryotubes (111.3%) than in bags (99.6%) in multiple myeloma (MM; p = 0.015). CFU‐GM decreased after thawing in all groups. CFU‐GM recovery was lower in cryotubes than in bags in MM (26.0% vs. 59.3%) and in Cy+G‐CSF mobilization (49.8% vs. 76.3%). CFU‐GM recovery in cryotubes was lower in MM compared with NHL (61.5%), HD (45.1%), and breast cancer (84.0%). Lymphocytes, monocytes, and granulocytes showed differences in the subgroups.

CONCLUSION: Cryopreservation negatively impacts in cell viability, CD34+ cell recovery, granulocytes, and CFU‐GM, although slight differences between the groups were observed. Cryotubes satisfactorily reflected the quality of the infused cells.
Estimate of the residual risk of transfusion‐transmitted human immunodeficiency virus infection in sub‐Saharan Africa: a multinational collaborative study
Authors: Lefrère Jean‐Jacques , Dahourouh Honorine , Dokekias Alexis E. , Kouao Maxime D. , Diarra Amadou , Diop Saliou , Tapko Jean‐Baptiste , Murphy Edward L. , Laperche Syria , Pillonel Josiane
Published: September 2010

BACKGROUND: Sub‐Saharan Africa remains the epicenter of the human immunodeficiency virus (HIV) pandemic. However, there is a lack of multicenter data on the risk of transfusion‐transmitted HIV from blood centers in sub‐Saharan Africa.

STUDY DESIGN AND METHODS: The incidence of HIV infections in the blood donations collected in the main blood banks of five countries (Burkina Faso, Congo, Ivory Coast, Mali, and Senegal) was determined to estimate the current transfusion risk of HIV infection using the incidence rate/window period model.

RESULTS: The risk of transfusion‐transmitted HIV infections associated with the window period varied from 1 in 90,200 donations (Senegal) to 1 in 25,600 (Congo). Considering the five participating blood centers as a whole, the incidence rate of HIV‐positive donors per 100,000 person‐years was 56.6 (95% confidence interval [CI], 47.1‐67.9); the residual risk (RR) was 34.1 (95% CI, 7.8‐70.7) per 1 million donations, which represents 1 in 29,000 donations (95% CI, 1/128,000‐1/14,000).

CONCLUSION: RR estimates varied according to the country. This is potentially due to a lower incidence of HIV infection in the general population or to a more efficient selection of blood donors in the countries with the lowest risk. The estimates of the transfusion risk of HIV infection in each country are important, both to assess the impact of current preventative strategies and to contribute data to policy decisions to reinforce transfusion safety.
Quantitative Microbial Risk Assessment of Cryptosporidiosis and Giardiasis from Very Small Private Water Supplies
Authors: Hunter Paul R. , de Sylor Marianna Anderle , Risebro Helen L. , Nichols Gordon L. , Kay David , Hartemann Philippe
Published: September 2010

This article reports a quantitative microbial risk assessment of the risk of Giardia and Cryptosporidium in very small private water supplies. Both pathogens have been implicated in causing outbreaks of waterborne disease associated with such supplies, though the risk of endemic disease is not known. For exposure assessments, we used existing data to derive regression equations describing the relationships between the concentration of these pathogens and Escherichia coli in private water supplies. Pathogen concentrations were then estimated using national surveillance data of E. coli in private water supplies in England and France. The estimated risk of infection was very high with the median annual risk being of the order of 25–28% for Cryptosporidium and 0.4% to 0.7% for Giardia, though, in the poorer quality supplies the risk could be much higher. These risks are substantially greater than for public water supplies and well above the risk considered tolerable. The observation that observed infection rates are generally much lower may indicate increased immunity in people regularly consuming water from private supplies. However, this increased immunity is presumed to derive from increased disease risk in young children, the group most at risk from severe disease.
Is Risk‐Based Regulation Feasible? The Case of Polybrominated Diphenyl Ethers (PBDEs)
Authors: MacGillivray Brian Hector , Alcock Ruth E. , Busby Jerry
Published: September 2010

The polybrominated diphenyl ethers (PBDEs) are a class of brominated flame retardants used extensively in an array of textiles and plastics. Initially viewed as inert and nontoxic, in recent years an emerging body of science has cast doubt on this perception. Consequently, the compounds have drawn sustained government, media, and lobby group focus in the United States and Europe, yet have taken contrasting trajectories in different risk regulation regimes. We present a longitudinal analysis of these pathways, examining the actions of legislatures, executives, courts, scientists, and pressure groups. We show that the emergence and resolution of PBDEs as a risk issue was strongly shaped by path dependency, political entrainment (inter‐institutional conflict unrelated to PBDEs), and partisan lawmaking. This raises the question of whether risk‐based principles are capable of being the foundation on which managing the potential for harm can be based—even when that harm is associated with specific objects like flame‐retardant chemicals. We conclude by reflecting on the difficult normative issues that are raised.
Consumer Responses to Integrated Risk‐Benefit Information Associated with the Consumption of Food
Authors: van Dijk Heleen , Fischer Arnout R.H. , Frewer Lynn J.
Published: September 2010

The risk analysis of the health impact of foods is increasingly focused on integrated risk‐benefit assessment, which will also need to be communicated to consumers. It therefore becomes important to understand how consumers respond to integrated risk‐benefit information. Quality‐adjusted‐life‐years (QALYs) is one measure that can be used to assess the balance between risks and benefits associated with a particular food. The effectiveness of QALYs for communicating both positive and negative health effects associated with food consumption to consumers was examined, using a 3 × 2 experiment varying information about health changes in terms of QALYs associated with the consumption of fish (n = 325). The effect of this information on consumer perceptions of the usefulness of QALYs for describing health effects, on risk and benefit perceptions, attitudes, and intentions to consume fish was examined. Results demonstrated that consumers perceived QALYs as useful for communicating health effects associated with food consumption. QALYs communicated as a net effect were preferred for food products associated with negative net effects on health, while separate communication of both risks and benefits may be preferred for food products associated with positive or zero net health effects. Information about health changes in terms of QALYs facilitated informed decision making by consumers, as indicated by the impact on risk and benefit perceptions as intended by the information. The impact of this information on actual food consumption choices merits further investigation.
Nanostructured La1−xSrxGa1−yMgyO3−δ Ceramics Processed by Spark Plasma Sintering of Mechanosynthesized Precursors
Authors: Moure Alberto , Castro Alicia , Galy Jean , Moure Carlos , Tartaj Jesus
Published: September 2010

Nanostructured ceramics with La1−xSrxGa1−yMgyO3−δ composition have been processed by spark plasma sintering of precursors obtained by mechanosynthesis. The compositions with x=0.10 and y=0.20 are single‐phase ceramics even at the lowest processing temperatures of 900°C. For x=0.20, y=0.17, typical secondary phases as SrLaGaO4 and SrLaGa3O7 appear at all the processing temperatures, from 900° to 1100°C. The high reactivity of the precursors due to the prolonged milling allows highly densified ceramics (>98%) to be obtained at moderate applied pressures (100 MPa), and at temperatures for which the nanostructure scale is maintained. Single‐phase ceramics present higher conductivity than those with isolating secondary phases. The nanostructure appears to break the vacancies ordering, and the conductivity is produced through random vacancies paths, diminishing the activation energy and increasing the total conductivity of the ceramics.
Radially Oriented ZnO Nanowires on Flexible Poly‐l‐Lactide Nanofibers for Continuous‐Flow Photocatalytic Water Purification
Authors: Sugunan Abhilash , Guduru Veerendra K. , Uheida Abdusalam , Toprak Muhammet S. , Muhammed Mamoun
Published: September 2010

Several oxide ceramics, notably ZnO and TiO2 are known to catalyze decomposition of organic molecules in water under ultraviolet (UV) irradiation. Here we describe fabrication of highly flexible ZnO‐based hierarchical nanostructure obtained by growing radially oriented ZnO nanowires on poly‐l‐lactide nanofibers. Utilizing the flexibility and high surface area of polymeric nanofibers as novel substrate for growth of the photochemically active ZnO nanowires we show a proof‐of‐principle demonstration of a continuous flow water treatment setup. We have monitored photocatalytic decomposition of known organic pollutants, such as methylene blue, monocrotophos, and diphenylamine under illumination with UV light using this highly flexible hierarchical nanostructure.
Structural, Dielectric, and Pyroelectric Properties of (1−x)PbSc0.5Ta0.5O3–(x)PbHfO3 Ceramics
Authors: Liu Wei , Wang Genshui , Cao Sheng , Mao Chaoliang , Dong Xianlin
Published: September 2010

The solid solutions of (1−x)PbSc0.5Ta0.5O3–(x)PbHfO3 (PSTH(x)) with pure perovskite structure were fabricated by hot‐pressing sintering method. The structural, dielectric, and pyroelectric properties of the PSTH(x) ceramics were investigated. It was found that the long‐range ordering decreased and the grain size increased with the increase of x. The maximum dielectric constant of 21 000 at 100 Hz and the highest pyroelectric coefficient of 615 × 10−8 C·(cm2·K)−1 were obtained for an x value of 0.15, where the PSTH(x) ceramic showed the largest lattice distortion.
Influence of Nonstoichiometry on Extrinsic Electrical Conduction and Microwave Dielectric Loss of BaCo1/3Nb2/3O3Ceramics
Authors: Li Ming , Feteira Antonio , Mirsaneh Mehdi , Lee Soonil , Lanagan Michael T. , Randall Clive A. , Sinclair Derek C.
Published: September 2010

The microwave (MW) dielectric loss (or quality factor,Q) of BaCo1/3Nb2/3O3(BCN) ceramics exhibits a strong dependence on sample‐processing conditions and is not always consistent with the degree of 1:2 B‐site cation ordering. Impedance spectroscopy results reveal that these BCN ceramics exhibit remarkably different electrical properties due to low levels of nonstoichiometry induced during ceramic processing. These compositional changes are difficult to detect by common chemical techniques but can have a significant influence on the electrical properties, and in particular on the extrinsic electrical conduction andQ. The influence of extrinsic conduction induced by ceramic processing should therefore be considered when optimizingQin MW dielectric ceramics.
Thermochemistry of Lanthana‐ and Yttria‐Doped Thoria
Authors: Aizenshtein Michael , Shvareva Tatiana Y. , Navrotsky Alexandra
Published: September 2010

Lanthanide‐doped thoria is relevant both to nuclear energy and to solid oxide fuel cell technology. It is also a simple model system in which oxygen vacancy concentration is directly proportional to doping with no complication from oxidation–reduction reactions, ordered phases, or phase transitions in the tetravalent oxide. Despite this relevance, only few thermodynamic data are available for such systems. In the present study, LaxTh1−xO2−0.5x(0<x<0.50) and YxTh1−xO2−0.5x(0<x<0.18) have been synthesized, characterized, and systematically studied for the first time using high‐temperature oxide melt solution calorimetry. Two competing effects contribute to the energetics: endothermic deviation from ideality related to cation size difference and partial stabilization of the system due to the exothermic formation of defect clusters. The former can be described by endothermic regular solution interaction parameters of 119.3 ± 11.4 kJ/mol for the yttria system and 27.8 ± 4.1 kJ/mol for the lanthana system. The latter can be described by exothermic vacancy clustering or defect association energies of –116.3 ± 23.3 kJ/mol for yttria‐doped thoria and –98.6 ± 19.7 kJ/mol for lanthana‐doped thoria.
Microstructure and Mechanical Properties of Zirconium Diboride Obtained by Aqueous Tape Casting Process and Hot Pressing
Authors: Lü Zhihui , Jiang Dongliang , Zhang Jingxian , Lin Qingling
Published: September 2010

Aqueous ZrB2 suspensions with different content of B4C were prepared for tape casting. After drying, the green tapes were laminated and hot pressed. It was shown that the mechanical properties of the sintered bodies increased with the increase in B4C content, while the ZrB2 grain size decreased correspondingly. High sintering temperature also results in ZrB2 ceramics with higher relative density and larger grain size. The ZrB2 samples with 8 wt% B4C sintered at 1900°C had a relative density of 95.9 ± 2.0% and an average grain size of 2.80 ± 0.98 μm. The flexural strength, elastic modulus, Vickers hardness, and fracture toughness were 512.4 ± 63.9 MPa and 378.5 ± 43.7, 16.5 ± 0.7 GPa, and 2.76 ± 0.11 MPa·m1/2, respectively. Scanning electron microscopy and transmission electron microscopy showed a fine and homogeneous microstructure with a clear grain boundary. The fracture mode was mainly intragranular type.
Infrared‐Transparent Y2O3–MgO Nanocomposites Using Sol–Gel Combustion Synthesized Powder
Authors: Wang Jiwen , Chen Dianying , Jordan Eric H. , Gell Maurice
Published: September 2010

Y2O3–MgO composite nanopowder with a volume ratio of 50:50 was synthesized using a sol–gel combustion process. X‐ray diffraction analysis of the as‐synthesized nanopowder shows phase pure Y2O3 and MgO with a cubic crystal structure and crystalline size ∼15 nm. The fully dense Y2O3–MgO nanocomposites were prepared by pressureless sintering the composite nanopowder at 1400°C for 2 h, followed by hot isostatic pressing at 1350°C for 1 h and postsinter annealing at 1000°C for 10 h. The Y2O3–MgO nanocomposite exhibit excellent infrared transmittance (62%–80%) over 3–7 μm infrared wavelength ranges with an average hardness of 10.6 GPa.
Hexagonal BaTiO3:Eu3+ Nanoparticles: A Kinetically Stable Phase Prepared at Low Temperatures
Authors: Patel Dinesh K. , Vishwanadh Bathula , Sudarsan Vasanthakumaran , Vatsa Rajesh K. , Kulshreshtha Shailendra K.
Published: September 2010

Nanoparticles of Eu3+‐doped BaTiO3 having a hexagonal structure, which is a thermodynamically stable phase above 1432°C, have been prepared at a low temperature of 110°C based on the coprecipitation of Ti4+, Ba2+, and Eu3+ in ethylene glycol medium by adding urea. Based on differential thermal analysis studies, it is inferred that the as‐prepared hexagonal phase of BaTiO3:Eu3+ is unstable and decomposes to the anatase form of TiO2 and barium carbonate above 420°C. Luminescence properties of the hexagonal form of BaTiO3:Eu3+ nanoparticles have been compared with cubic BaTiO3:Eu3+ nanoparticles prepared by the combustion method. Based on the detailed luminescence studies of Eu3+ in both cubic and hexagonal form of BaTiO3 samples, it is inferred that Eu3+ ions mainly occupy the Ti4+ sites in hexagonal BaTiO3 and both Ba2+ and Ti4+ sites in cubic BaTiO3. A comparison of the luminescence properties of Eu3+ in hexagonal and cubic form of BaTiO3 suggested that there is increased distortion around Eu3+ in hexagonal BaTiO3 phase compared with cubic BaTiO3 phase, and this has been explained in terms of the distorted environment created around larger ionic radii Eu3+ ions occupying the smaller ionic radii Ti4+ site. There is a significant difference in the decay constant for 5D0 level of Eu3+ for these two forms of BaTiO3:Eu3+ nanoparticles.
Kinetics of Thermal Oxidation of Titanium Nitride Powder at Different Oxidizing Atmospheres
Authors: Hou Xin‐Mei , Hu Xiao‐Jun , Chou Kuo‐Chih
Published: September 2010

The oxidation behavior of titanium nitride powder at different oxidizing atmospheres was investigated using thermogravimetric analysis, X‐ray diffraction, and scanning electron microscopy. Oxidation experiments have been carried out both in isothermal as well as nonisothermal modes. The nonisothermal oxidation result showed that the oxidation rate was affected by temperature, heating rate, and oxygen partial pressure. The isothermal oxidation result showed that the diffusion of oxygen through the oxide product layer to the oxide/titanium nitride interface was the rate‐controlling step and the oxidation product became obviously porous at elevated temperature. In view of the oxidation kinetics, Chou model, which quantitatively expresses the oxidation weight increment as a function of time, heating rate, temperature, and oxygen partial pressure, has been employed and gotten a good agreement.
Slow Crack Growth Behavior of Zirconia‐Toughened Alumina and Alumina Using the Dynamic Fatigue Indentation Technique
Authors: Ramalingam Subramanian , Reimanis Ivar E. , Fuller Edwin R. , Haftel Jonathan D.
Published: September 2010

A dynamic fatigue indentation technique was used to determine the slow crack growth (SCG) parameters of a medical‐grade platelet‐reinforced zirconia‐toughened alumina and two different fine‐grain aluminas: one a common grade of nominal 99.5% purity, and the other a high‐purity (99.94%) medical‐grade alumina. Fatigue tests in bending were performed at various loading rates with precracked Vickers indentations in 100% relative humidity conditions. Inert strength tests were performed in dry nitrogen. The dynamic fatigue analysis accounts for the presence of the indentation. The SCG power law exponent was found to be 36, 65, and 93 for the 99.5% alumina, the 99.94% alumina, and the zirconia‐toughened alumina, respectively. The presence of glassy phase likely increases SCG in the 99.5% alumina compared with the higher purity alumina. The zirconia‐toughened alumina exhibits a relatively steep R curve that forms due to two toughening mechanisms: platelet reinforcement and transformation toughening. It is apparent that neither of mechanisms degrades significantly due to moisture‐assisted SCG.
Flash Sintering of Nanograin Zirconia in <5 s at 850°C
Authors: Cologna Marco , Rashkova Boriana , Raj Rishi
Published: September 2010

We show that yttrium‐stabilized zirconia can be sintered in a few seconds at ∼850°C to full density, starting from a green density of 0.5, by the application of a dc electrical field (nominally, several hours at 1450°C are needed to complete the sintering process). This finding is explained by the local Joule heating at grain boundaries, which, on the one hand, promotes grain‐boundary diffusion (a kinetic effect), while at the same time restricts grain growth (a thermodynamic effect). The smaller grain size and the higher temperature at grain boundaries can then act synergistically to enhance the rate of sintering. These results have a bearing in explaining the widespread spark plasma and microwave‐assisted techniques for enhanced sintering.
From Three‐Dimensional Flower‐Like α‐Ni(OH)2 Nanostructures to Hierarchical Porous NiO Nanoflowers: Microwave‐Assisted Fabrication and Supercapacitor Properties
Authors: Ren Yang , Gao Lian
Published: September 2010

A facile method is presented to prepare flower‐like α‐Ni(OH)2 involving only microwave heating of nickel nitrate hydrate in ethanol solvent without any hard/soft templates or precipitate‐controlling agents. After calcination procedure, hierarchical and porous NiO nanoflowers with large BET‐specific surface areas and controlled pore‐size distributions are readily fabricated. A possible formation mechanism is proposed based on self‐assembly under microwave heating. The structure, morphology, and crystalline phase of the products are characterized by transmission electron microscopy (TEM), X‐ray diffraction, thermogravimetric analysis, Fourier transform infrared spectroscopy, and N2 adsorption/desorption isotherm analysis. TEM reveals that the obtained NiO nanoflowers have uniform size and are composed of sheet‐like petals that are built up from nanocrystals. The resultant NiO nanostructures present a specific capacitance as high as 277 F/g and good cycling stability.
Ultra‐Fine Tungsten Carbide Powder Prepared by a Nitridation–Carburization Method
Authors: Sun Shi‐Kuan , Kan Yan‐Mei , Zhang Guo‐Jun , Wang Pei‐Ling
Published: September 2010

WC powder was synthesized by a nitridation–carburization method with WO3 prepared by the citrate sol–gel route as the starting material, and the reaction mechanism was investigated. It was found that WO3 was converted to nanosized W2N after the nitridation process in NH3. Then, the W2N was transformed to W metal, W2C, and WC in sequence when it was carburized in CH4–H2 gas mixture. The WC powder obtained possessed a high specific surface area of 24.6 m2/g, and showed a particle size of 20–30 nm, which was much finer than the WC powder prepared by direct carburization of WO3 in CH4–H2 gas mixture. The reason was also discussed.
Temperature Dependence of Effective Grain Core/Single Crystal Dielectric Constants for Acceptor‐Doped Oxygen Ion Conductors
Authors: Perry Nicola H. , Yeh Ted C. , Mason Thomas O.
Published: September 2010

Effective grain core or single crystal dielectric constants of four solid oxide electrolytes—yttria‐stabilized zirconia (YSZ with 8 and 7 mol% yttria), tetragonal zirconia polycrystals (TZP with 3 mol% yttria), strontium‐ and magnesium‐doped lanthanum gallate (LSGM), and gadolinia‐doped ceria (GDC, with 20 mol% gadolinia)—were studied as a function of temperature by AC‐impedance spectroscopy and equivalent circuit fitting. Unlike their undoped counterparts, the acceptor‐doped oxides consistently exhibited an upturn in effective grain core/single crystal dielectric constant in the vicinity of 350–500 K. This temperature‐dependent behavior was attributed to the onset of thermally activated dipolar relaxation—an explanation supported by the appearance of loss tangent peaks at higher temperatures. Differences between “effective” dielectric constants and frequency‐dependent complex dielectric constants for the grain core/single crystal frequency range, and applications of the effective dielectric constant data are discussed.
Spin Spray‐Deposited Nickel Manganite Thermistor Films For Microbolometer Applications
Authors: Ko Song Won , Li Jing , Podraza Nikolas J. , Dickey Elizabeth C. , Trolier‐McKinstry Susan
Published: September 2010

Nickel manganite thin films are good candidates for thermal imaging applications because of their large temperature coefficient of resistance (TCR), (>−3%/K) and good environmental stability. To enable low‐temperature deposition (90°C) on preexisting circuitry, a spin spray technique was developed for these materials. As‐deposited manganese oxide films show well‐developed X‐ray diffraction patterns, while as‐deposited nickel manganite films exhibit a nanocrystalline spinel structure. Low‐temperature (400°C) postdeposition annealing leads to densification of the nanocrystalline nickel manganite spinel films. Spectroscopic ellipsometry measurements on annealed films provide complex dielectric function spectra over a range from 0.75 to 5.15 eV with comparable features with those found in films prepared by a chemical solution method. Energy‐dispersive X‐ray spectroscopy indicates that the final composition of the films is Ni deficient relative to the starting solution composition. The TCR of the nickel manganite films annealed at 400°C in an argon atmosphere is −3.6%/K. Doping the nickel manganite films with zinc results in an improvement of crystallinity, but leads to substantial increases in the electrical resistivity. Copper doping reduces the resistivity of the films to <1.0 kΩ·cm without degrading the crystalline quality, thus resulting in films suitable for microbolometer applications.