bluuebunny/crossref_metadata_2025 huggingface dataset:
Malus hupehensis NPR1 induces pathogenesis‐related protein gene expression in transgenic tobacco
Authors: Zhang J.‐Y. , Qiao Y.‐S. , Lv D. , Gao Z.‐H. , Qu S.‐C. , Zhang Z.
Published: June 2011

Most commercially grown apple cultivars are susceptible to fungal diseases. Malus hupehensis has high resistance to many diseases affecting apple cultivars. Understanding innate defence mechanisms would help to develop disease‐resistant apple crops. Non‐expressor of pathogenesis‐related genes 1 (NPR1) plays a key role in regulating salicylic acid (SA)‐mediated systemic acquired resistance (SAR). MhNPR1 cDNA, corresponding to genomic DNA and its 5′ flanking sequences, was isolated from M. hupehensis. Sequence analysis showed that the regulatory mechanism for oligomer–monomer transition of the MhNPR1 protein in apple might be similar to that of GmNPR1 in soybean, but different from that of AtNPR1 in Arabidopsis. No significant differences in MhNPR1 expression were found in M. hupehensis after infection with Botryosphaeria berengeriana, showing that MhNPR1 might be regulated by pathogens at the protein level, as described for Arabidopsis and grapevine. SA treatment significantly induced MhNPR1 expression in leaves, stems and roots, while methyl jasmonate (MeJA) treatment induced MhNPR1 expression in roots, but not in leaves or stems. The expression of MhNPR1 was highly increased in roots, moderately in leaves, and did not change in stems after treatment with 1‐aminocyclopropane‐1‐carboxylic acid (ACC). SAR marker genes (MhPR1 and MhPR5) were induced by SA, MeJA and ACC in leaves, stems and roots. Overexpression of MhNPR1 significantly induced the expression of pathogenesis‐related genes (NtPR1, NtPR3 and NtPR5) in transgenic tobacco plants and resistance to the fungus Botrytis cinerea, suggesting that MhNPR1 orthologues are a component of the SA defence signalling pathway and SAR is induced in M. hupehensis.
Phylogeography of Acesta clams from submarine seamounts and escarpments along the western margin of North America
Authors: Clague Gillian E. , Jones William Joe , Paduan Jennifer B. , Clague David A. , Vrijenhoek Robert C.
Published: June 2011

Genetic connectivity and habitat characteristics were examined in two species of Acesta clams (Bivalvia: Limidae) from submarine seamounts and continental slopes along the western North America margin. Two species were identified from dive videos obtained with submarine remotely operated vehicles that surveyed a 2200‐km range between 27° and 46° N latitude. Acesta sphoni was only found at shallower habitats (545–860 m depth) in the southern part of this range, whereas Acesta mori was more abundant and widely distributed in deeper habitats (1029–1996 m). Both species occurred on seamounts and on the walls of submarine canyons and continental slopes. Segregation of these species by depth exposes them to correlated differences in water temperatures and dissolved oxygen concentrations. Ninety‐eight individuals sampled from seven seamounts and one escarpment locality were characterized with DNA‐barcodes based on 643 base pairs of mitochondrial cytochrome‐c‐oxidase subunit I (COI). Further analysis of these sequences revealed no significant geographical subdivision across the sampled range. This lack of differentiation suggests ongoing genetic exchange between the seamount populations and those possibly distributed along the continental margins. Examination of regional bathymetric profiles suggested that an abundance of suitable habitat might exist along these margins.
Stress Preconditioning of Boar Spermatozoa: A New Approach to Enhance Semen Quality*
Authors: Pribenszky C , Horváth A , Végh L , Huang S‐Y , Kuo Y‐H , Szenci O
Published: June 2011

Contents

Semen preparation and cryopreservation require finely adjusted procedures. Gametes are sensitive to environmental stresses, so in vitro procedures aim to minimize the inevitable harmful conditions. Applying stress to precondition cells has only been investigated recently. Studies demonstrated that by utilizing a well defined and properly applied hydrostatic pressure (HP) stress treatment to spermatozoa before in vitro storage, cryopreservation or insemination, cell survival and fertility improved compared with untreated controls. The birth of healthy piglets from treated fresh or frozen‐thawed semen demonstrates the in vivo safety of the procedure. Although the biological mechanism is still unclear, several processes incorporating cellular stress response might explain the observations. This paper summarizes results, background, aspects and considerations of HP treatment for porcine semen. The new principle, i.e. to improve the stress tolerance by a defined sublethal stress may outline a new strategy in assisted reproductive technologies with unique theoretical and practical consequences.
Semen Traits and Seminal Plasma Biochemical Parameters in White Leghorn Layer Breeders
Authors: Khan RU , Laudadio V , Tufarelli V.
Published: June 2011

Contents

This study was designed to determine the semen quality and seminal plasma biochemical parameters in White Leghorn layer breeders in the early phase of maturity. Individual ejaculates from 25 males were analysed for the determination of volume, sperm concentration, dead sperm percentage (DS) and sperm motility. Seminal plasma was separated and analysed for total oxidant status (TOS), total antioxidant capacity (TAC), paraoxonase (PON1), arylesterase, ceruloplasmin, triiodothyronine, thyroxine, aspartate aminotransferase (AST) and alanine aminotransferase (ALT). Our findings showed a significant (p < 0.05) positive correlation between TOS and DS in layer breeders. The values of TAC were significantly negatively correlated with TOS and DS, while positively correlated with PON1. Conversely, AST showed significant negative correlation with motility and DS. Significantly, negative correlation was also observed between ALT and sperm concentration. In conclusion, these parameters provide some valuable basal data that may help better understanding the semen quality characteristics of White Leghorn layer breeders.
Neuroprotective effects of oestrogen against oxidative toxicity through activation of G‐protein‐coupled receptor 30 receptor
Authors: Liu Shui‐Bing , Han Jie , Zhang Nan , Tian Zhen , Li Xu‐Bo , Zhao Ming‐Gao
Published: June 2011

1. 17‐β‐oestradiol (E2) plays a critical role in neuroprotection through both genomic and non‐genomic mechanisms. The aim of the present study was to investigate the role of G‐protein‐coupled receptor 30 (GPR30), a new kind of oestrogen receptor, in the neuroprotection against oxidative insult.

2. The neuroprotection evoked by GPR30 stimulation was examined in cultured cortical neurons. Hoechst 33258/propidium iodide double staining, flow cytometric analysis and western blotting were applied to assess neuronal apoptosis induced by H2O2.

3. We found that the GPR30 agonist, G1, and E2 attenuated apoptosis induced by H2O2 exposure. Furthermore, G1 (1 nmol/L) or E2 (1 nmol/L) significantly increased the levels of phosphorylated extracellular signal‐regulated kinase 1/2 (p‐ERK1/2), Bcl‐2 and pro‐caspase‐3. Pretreatment with ICI182780, a highly selective nuclear oestrogen receptor antagonist that is used to block the classical ERα and ERβ receptors, did not totally block the neuroprotective effects of E2 (1 nmol/L) and had no effect on the neuroprotective effects of G1 (1 nmol/L).

4. Our data suggest that GPR30 is involved in the neuroprotection against oxidative insult. The neuroprotection evoked by GPR30 stimulation was associated with the signalling through the ERK1/2 kinase pathway. In addition, the anti‐apoptotic activity of GPR30 was dependent on the expression of Bcl‐2 and pro‐caspase‐3. GPR30 might be a potential therapeutic target for neuroprotection and oxidative stress.
Diaphragm and peripheral muscle thickness on ultrasound: Intra‐rater reliability and variability of a methodology using non‐standard recumbent positions
Authors: BALDWIN CLAIRE E. , PARATZ JENNIFER D. , BERSTEN ANDREW D.
Published: June 2011

Background and objective:  Reliable measurement of diaphragm and peripheral muscle thickness, using diagnostic ultrasound, has only been validated in the erect posture. However, in many clinical populations, including critically ill patients, the erect posture presents logistic difficulties. This study aimed to validate ultrasound measurement of diaphragm and peripheral muscle thickness in the recumbent position.

Methods:  An observational methodology of repeated but blind ultrasound and anthropometric measurements was applied, to assess inta‐rater reliability. Thirteen healthy volunteers (aged 20–73 years) participated. A pneumotachograph was used to target lung volume, as diaphragm thickness was measured from ultrasound at end‐expiration, and both 25% and 50% of inspiratory capacity, while semi‐recumbent. The thicknesses of the mid‐upper arm, mid‐forearm and mid‐thigh musculature were also measured bilaterally while supine.

Results:  Diaphragm thickness could be reliably measured at end‐expiration (intra‐class correlation coefficient (ICC) = 0.990, 95% confidence interval: 0.918–0.998), 25% of inspiratory capacity (ICC = 0.959 (0.870–0.988)) and 50% of inspiratory capacity (ICC = 0.994 (0.980–0.998)). Peripheral muscle thickness measurements were also reliable (ICC = 0.998–1.0). Supine anthropometric measurements of limb segment lengths and girths were highly reproducible.

Conclusions:  This ultrasound technique has good reliability in recumbent positions, making it useful for application to clinical populations when the erect posture is not practical.
Masting in a temperate tree: Evidence for environmental prediction?
Authors: BURNS K. C.
Published: June 2011

Many plant species produce large fruit crops in some years and then produce few or no fruits in others. Synchronous, inter‐annual variation in plant reproduction is known as ‘masting’ and its adaptive significance has yet to be fully resolved. For 8 consecutive years, I quantified every fruit produced by 22 females of a New Zealand tree species (Dysoxylum spectabile), which has an unusual habit of taking a full calendar year to mature fruits after flowering. Fruit production varied strongly among years and was tightly synchronized among trees. Annual variability in fruit production declined with total reproductive output, indicating trees with lower fecundity exhibited a stronger tendency to mast. Although unrelated to temperature, annual fruit production was positively related to precipitation during annual periods of fruit development, and negatively related to fruit production in the previous year. Seedlings had higher rates of survivorship in a wet, high‐seed year than in a dry, low‐seed year, suggesting that seedlings might be drought sensitive. Therefore, D. spectabile produced large fruit crops during periods of high rainfall prior to fruit maturation, which may enhance survivorship of drought‐intolerant seeds. Results were inconsistent with several hypotheses that are widely believed to be the most likely explanations for masting. Instead, results were consistent with the environmental prediction hypothesis, suggesting that this hypothesis may be more important than previously appreciated.
Relationship between vegetation, hydrology and fluvial landforms on an unregulated sand‐bed stream in the Hunter Valley, Australia
Authors: CHALMERS ANITA C. , ERSKINE WAYNE D. , KEENE ANNABELLE F. , BUSH RICHARD T.
Published: June 2011

A survey of fluvial landforms was conducted at Widden Brook, an unregulated sand‐bed stream in the Hunter Valley, New South Wales (NSW), Australia, to investigate the physical factors associated with vegetation pattern in Riverine Oak Forest. Groundwater depth and chemistry (pH, dissolved oxygen and electrical conductivity) were measured using piezometers and submersible data loggers on three fluvial landforms (i.e. toe of bank, top of bank and floodplain) along five transects. Floristic composition, canopy cover, bare ground and leaf litter were assessed within 45 quadrats on the three landforms along the five transects. Elevation above the bed and flood return period were determined by cross‐sectional survey and flood frequency analysis, while flow duration was determined from the gauge record. Canonical correspondence analysis demonstrated that vegetation composition was associated with average watertable depth and flood variables to a similar extent. The relative importance of these factors would be expected to vary with flood‐ and drought‐dominated climatic periods on a scale of several decades. Floristic composition was moderately associated with the canopy cover of the dominant woody species, Casuarina cunninghamiana (Miq.), but weakly correlated with bare ground and groundwater chemistry. Suites of species were associated with particular fluvial landforms and their corresponding flood and watertable conditions. The reach examined has characteristics similar to both the semi‐arid and mesic riparian ecosystems of the USA. The coarse sediments, high flood variability, short flood duration and dominance by a pioneer tree that relies on groundwater are similar to riparian ecosystems in the western USA, while the relatively broad floodplain and the development of a forest canopy that is associated with the distribution of understorey plants are similar to the mesic riparian systems in the eastern USA.
Impact of expected value on neural activity in rat substantia nigra pars reticulata
Authors: Bryden Daniel W. , Johnson Emily E. , Diao Xiayang , Roesch Matthew R.
Published: June 2011

The substantia nigra pars reticulata (SNr) is thought to serve as the output of the basal ganglia, whereby associative information from striatum influences behavior via disinhibition of downstream motor areas to motivate behavior. Unfortunately, few studies have examined activity in SNr in rats making decisions based on the value of predicted reward similar to those conducted in primates. To fill this void, we recorded from single neurons in SNr while rats performed a choice task in which different odor cues indicated what reward was available on the left or on the right. The value of reward associated with a leftward or rightward movement was manipulated by varying the size of and delay to reward in separate blocks of trials. Rats were faster or slower depending on whether the expected reward value was high or low, respectively. The number of neurons that increased firing during performance of the task outnumbered those that decreased firing. Both increases and decreases were modulated by expected value and response direction. Neurons that fired more or less strongly for larger reward tended to fire, respectively, more or less strongly for immediate reward, reflecting their common motivational output. Finally, value selectivity was present prior to presentation of cues indicating the nature of the upcoming behavioral response for both increasing‐ and decreasing‐type neurons, reflecting the internal bias or preparatory set of the rat. These results emphasize the importance of increasing‐type neurons on behavioral output when animals are making decisions based on predicted reward value.
Flexible Work Arrangements Availability and their Relationship with Work‐to‐Family Conflict, Job Satisfaction, and Turnover Intentions: A Comparison of Three Country Clusters
Authors: Masuda Aline D. , Poelmans Steven A.Y. , Allen Tammy D. , Spector Paul E. , Lapierre Laurent M. , Cooper Cary L. , Abarca Nureya , Brough Paula , Ferreiro Pablo , Fraile Guillermo , Lu Luo , Lu Chang‐Qin , Siu Oi Ling , O'Driscoll Michael P. , Simoni Alejandra Suarez , Shima Satoru , Moreno‐Velazquez Ivonne
Published: June 2011

The present study explored the availability of flexible work arrangements (FWA) and their relationship with manager outcomes of job satisfaction, turnover intentions, and work‐to‐family conflict (WFC) across country clusters. We used individualism and collectivism to explain differences in FWA availability across Latin American, Anglo, and Asian clusters. Managers from the Anglo cluster were more likely to report working in organisations that offer FWA compared to managers from other clusters. For Anglo managers, flextime was the only FWA that had significant favorable relationships with the outcome variables. For Latin Americans, part‐time work negatively related with turnover intentions and strain‐based WFC. For Asians, flextime was unrelated to time‐based WFC, and telecommuting was positively associated with strain‐based WFC. The clusters did not moderate the compressed work week and outcome relationships. Implications for practitioners adopting FWA practices across cultures are discussed.
For Fun, Love, or Money: What Drives Workaholic, Engaged, and Burned‐Out Employees at Work?
Authors: van Beek Ilona , Hu Qiao , Schaufeli Wilmar B. , Taris Toon W. , Schreurs Bert H.J.
Published: June 2011

Previous research has distinguished between two types of working hard: workaholism, a “bad” type of working hard, and work engagement, a “good” type of working hard. However, the motivations underlying workaholism and work engagement have not been examined extensively. Building on Deci and Ryan's Self‐Determination Theory, the present study examined the motivational correlates of workaholism, work engagement, and burnout (a possible consequence of working hard), using data from Chinese health care professionals (544 nurses and 216 physicians), and controlling for job demands and resources. As expected, structural equation modeling revealed that high levels of workaholism were associated with high levels of introjected regulation and identified regulation; that high levels of work engagement were mainly associated with high levels of intrinsic regulation; and that high levels of burnout were mainly associated with low levels of intrinsic regulation. Thus, different types of motivational regulation are associated with different types of job‐related well‐being.
Promoting Creativity at Work: The Role of Problem‐Solving Demand
Authors: Zhou Qin , Hirst Giles , Shipton Helen
Published: June 2011

We propose that problem‐solving demand (PSD) is an important job attribute for employees' creative performance. Applying job design theory, we examined the relationship between PSD and employee creativity. The theorised model was tested with data obtained from a sample of 270 employees and their supervisors from three Chinese organisations. Regression results revealed that PSD was positively related to creativity, and this relationship was mediated by creative self‐efficacy. Additionally, intrinsic motivation moderated the relationship between PSD and creative self‐efficacy such that the relationship was stronger for individuals with high rather than low intrinsic motivation. We discuss our findings, implications for practice, and future research.
Intangible assets, IFRS and analysts’ earnings forecasts
Authors: Chalmers Keryn , Clinch Greg , Godfrey Jayne M. , Wei Zi
Published: June 2011

We investigate whether the adoption of International Financial Reporting Standards (IFRS) in 2005 by Australian firms has been associated with a loss of potentially useful information about intangible assets. We find that the negative association between the accuracy and dispersion of analysts’ earnings forecasts and aggregate reported intangibles previously documented by Matolcsy and Wyatt (2006) becomes stronger subsequent to IFRS adoption, primarily for firms with high levels of underlying intangible assets. Our result is largely attributable to reported goodwill, rather than other intangible assets, suggesting that the impairment approach to goodwill valuation required by IFRS conveys more useful information than does the former straight‐line amortization approach. When we investigate a sub‐sample of firms that report lower intangibles under IFRS than under the prior Australian GAAP, we do find some evidence consistent with a loss of useful information relating to intangibles.
Overexpression of Brassica juncea wild‐type and mutant HMG‐CoA synthase 1 in Arabidopsis up‐regulates genes in sterol biosynthesis and enhances sterol production and stress tolerance
Authors: Wang Hui , Nagegowda Dinesh A. , Rawat Reetika , Bouvier‐Navé Pierrette , Guo Dianjing , Bach Thomas J. , Chye Mee‐Len
Published: June 2011

Brassica juncea 3‐hydroxy‐3‐methylglutaryl‐CoA synthase (HMGS) is encoded by four isogenes (BjHMGS1‐BjHMGS4). In vitro enzyme assays had indicated that the recombinant BjHMGS1 H188N mutant lacked substrate inhibition by acetoacetyl‐CoA (AcAc‐CoA) and showed 8‐fold decreased enzyme activity. The S359A mutant demonstrated 10‐fold higher activity, while the H188N/S359A double mutant displayed a 10‐fold increased enzyme activity and lacked inhibition by AcAc‐CoA. Here, wild‐type and mutant BjHMGS1 were overexpressed in Arabidopsis to examine their effects in planta. The expression of selected genes in isoprenoid biosynthesis, isoprenoid content, seed germination and stress tolerance was analysed in HMGS overexpressors (OEs). Those mRNAs encoding enzymes 3‐hydroxy‐3‐methylglutaryl‐CoA reductase (HMGR), sterol methyltransferase 2 (SMT2), delta‐24 sterol reductase (DWF1), C‐22 sterol desaturase (CYP710A1) and brassinosteroid‐6‐oxidase 2 (BR6OX2) were up‐regulated in HMGS‐OEs. The total sterol content in leaves and seedlings of OE‐wtBjHMGS1, OE‐S359A and OE‐H188N/S359A was significantly higher than OE‐H188N. HMGS‐OE seeds germinated earlier than wild‐type and vector‐transformed controls. HMGS‐OEs further displayed reduced hydrogen peroxide (H2O2)–induced cell death and constitutive expression of salicylic acid (SA)‐dependent pathogenesis‐related genes (PR1, PR2 and PR5), resulting in an increased resistance to Botrytis cinerea, with OE‐S359A showing the highest and OE‐H188N the lowest tolerance. These results suggest that overexpression of HMGS up‐regulates HMGR, SMT2, DWF1, CYP710A1 and BR6OX2, leading to enhanced sterol content and stress tolerance in Arabidopsis.
Syntax‐Pragmatics Interface: Mandarin ChineseWh‐the‐helland Point‐of‐View Operator
Authors: Chou Chao‐Ting Tim
Published: June 2011

Abstract. Based on previously unnoted data concerningwh‐the‐hellattitude‐bearing questions in Mandarin Chinese, I argue that integrating the pragmatic notion “point of view” into the syntactic computation enables us to capture certain properties ofwh‐the‐hellquestions in Mandarin Chinese in a systematic and illuminating way. The two central phenomena analyzed are (1) causalzenme‘how come’ is not compatible withdaodi‘the‐hell’ in Chinese, and (2) in Chinesewh‐the‐hellquestions, whendaodi‘the‐hell’ takes matrix scope while staying overtly in the embedded clause, the person feature of the matrix subject cannot be third person. I argue that explaining these phenomena depends on recognizing the logophoricity of the negative attitudes carried bydaodiand causalzenme. The valuation relation that I postulate between the Point‐of‐View operator and an unvalued Point‐of‐View feature ofdaodiand causalzenmenot only explains these data but also formally captures certain properties of the Chinese logophorziji(cf.Huang & Liu 2001).
Backward Raising
Authors: Potsdam Eric , Polinsky Maria
Published: June 2011

Abstract. This paper documents and analyzes an instance of covert A‐movement, specifically covert subject‐to‐subject raising, in the Northwest Caucasian language Adyghe. We argue that Adyghe has a subject‐to‐subject raising construction in which the subject of an unaccusative verb’s complement clause undergoes A‐movement into the matrix clause, but it does so covertly. We refer to this phenomenon asbackward raising. True backward raising is distinguished from apparent cases that have similar agreement patterns but do not show any of the other evidence for movement found in the Adyghe construction. We illustrate the contrast between true and apparent backward raising by comparing Adyghe to Greek. The existence of backward raising helps to adjudicate between various theories of covert movement. It supports a theory in which covert movement involves actual phrasal movement. Covert movement cannot be reduced to a long‐distance feature‐matching relation such as Agree (Chomsky 2000). Linguistic theory thus needs to incorporate both mechanisms.
EXCESS TRAVEL IN NON‐PROFESSIONAL TRIPS: WHY LOOK FOR IT MILES AWAY?
Authors: BOUSSAUW KOBE , VAN ACKER VERONIQUE , WITLOX FRANK
Published: June 2011

Based on the spatial distribution of some quasi‐daily destination classes and survey‐reported trip distances, regional variation in excess travel in non‐professional trips in Flanders (Belgium) is assessed. To this end, proximity to various quasi‐daily destinations is compared with the reported distance that is actually travelled to reach similar, but alternative, facilities. We note that in rural areas (compared with urban areas) larger distances are travelled, although the closest facility is chosen more often. In the most urbanised areas, however, we note that spatial proximity is also an important aspect in destination choice. Quantification of these phenomena can support the practice of sustainable spatial planning by distinguishing areas that are too mono‐functional or too remote, and therefore need more functional diversity, and by identifying areas where densification is useful because the location is close to most quasi‐daily destinations, reducing the need to travel over large distances.
BEYOND POSTSUBURBIA? MULTIFUNCTIONAL SERVICE AGGLOMERATION IN VIENNA'S URBAN FRINGE
Authors: HELBICH MARCO
Published: June 2011

The surroundings of European cities are becoming ever more complex and sophisticated landscapes. In recent years there has been an ongoing debate about urban fringes that are developing over and beyond the influence of postsuburban processes into decentralised and non‐centred urban landscapes. This paper addresses the urgent need to consider polycentric functional service clustering in the urban fringes based on empirical evidence gathered in Vienna, Austria, which served as a case study. A spatial scan statistic is applied to detect local spatial clusters of services and the bivariate K(d)‐function is used to investigate the spatial interaction between each nucleus. Due to some significant functional clusters, it has been concluded that agglomeration economies are still of prime interest. Furthermore, some significant attraction between the studied clusters is investigated. Overall, the results do not contradict the concept of postsuburbia yet, which is why a paradigm shift must be ruled out.
THE EXPECTED SHORTFALL OF QUADRATIC PORTFOLIOS WITH HEAVY‐TAILED RISK FACTORS
Authors: Broda Simon A.
Published: June 2011

Computable expressions are derived for the Expected Shortfall of portfolios whose value is a quadratic function of a number of risk factors, as arise from a Delta–Gamma–Theta approximation. The risk factors are assumed to follow an elliptical multivariate t distribution, reflecting the heavy‐tailed nature of asset returns. Both an exact expression and a uniform asymptotic expansion are presented. The former involves only a single rapidly convergent integral. The latter is essentially explicit, and numerical experiments suggest that its error is negligible compared to that incurred by the Delta–Gamma–Theta approximation.
THE NORMALIZING TRANSFORMATION OF THE IMPLIED VOLATILITY SMILE
Authors: Fukasawa Masaaki
Published: June 2011

We study specific nonlinear transformations of the Black–Scholes implied volatility to show remarkable properties of the volatility surface. No arbitrage bounds on the implied volatility skew are given. Pricing formulas for European payoffs are given in terms of the implied volatility smile.
CONTINUOUSLY MONITORED BARRIER OPTIONS UNDER MARKOV PROCESSES
Authors: Mijatović Aleksandar , Pistorius Martijn
Published: June 2011

In this paper, we present an algorithm for pricing barrier options in one‐dimensional Markov models. The approach rests on the construction of an approximating continuous‐time Markov chain that closely follows the dynamics of the given Markov model. We illustrate the method by implementing it for a range of models, including a local Lévy process and a local volatility jump‐diffusion. We also provide a convergence proof and error estimates for this algorithm.
The long‐term rise in overseas travel by Americans, 1820–20001
Authors: DUPONT BRANDON , GANDHI ALKA , WEISS THOMAS
Published: June 2011

How and when did the ‘great tourist invasion of Europe’ come about? Although a few writers have tried to characterize the rise in travel, their descriptions are almost exclusively narrative with colourful opinions and very little quantitative evidence. This is our attempt to fill in the gap. We have linked together several series on overseas travel in order to produce a consistent long‐term series covering the period 1820 to 2000, and have also constructed a new time series on passenger fares for much of the period in which ocean travel was the means of going abroad. We use these new data, along with other evidence on GDP per capita, air fares, exchange rates, and indexes of technological change in the travel industry, in an attempt to explain the long‐term rise in overseas travel.
Land abundance and economic institutions: Egba land and slavery, 1830–19141
Authors: FENSKE JAMES
Published: June 2011

The ‘land abundance’ view of African history uses sparse population to explain economic institutions. This article uses colonial court records to show that the Egba of Nigeria fit this theory's predictions. Before 1914, the Egba had imprecisely defined land rights, relied on dependent and forced labour, and used labour to secure loans. These institutions responded to the changing availability of land, labour, and capital. An initial period of land scarcity altered land ownership. A market existed for the most valuable land. Slaves were used by those with better opportunities to acquire them, and credit expanded after the introduction of tree crops.
An International Perspective on Risk Management Quality
Authors: Mira Svetlana , Taylor Nicholas
Published: June 2011

This paper introduces an alternative method for assessing the quality of risk management models. Specifically, using the forecast efficiency notion that forecast errors should be independent of a pertinent information set, we consider the extent to which unanticipated downside risk (extreme risk) is independent of overseas extreme risk. This is achieved using a bootstrap version of the non‐causality test recently introduced by Hong et al. (), data covering 45 international equity markets, and by measuring extreme risk via a class of risk management models recently introduced by Xiao and Koenker (). In doing this, we find significant evidence of transmission (causality) across national borders. Moreover, we discuss how risk managers in developed and emerging markets can parsimoniously incorporate such information (international dependency) into their risk management models to produce measures of downside risk that have more desirable ex post properties (viz. forecast efficiency properties).
Motor features and response to oral levodopa in patients with Parkinson’s disease under continuous dopaminergic infusion or deep brain stimulation
Authors: Elia A. E. , Dollenz C. , Soliveri P. , Albanese A.
Published: June 2011

Background:  Subthalamic nucleus deep brain stimulation (STN DBS) and continuous dopaminergic infusions (jejunal levodopa or subcutaneous apomorphine) are indicated in complicated Parkinson’s disease (PD), although it remains unsettled how they compare to each other.

Methods:  We investigated the daytime motor condition in patients with advanced PD under monotherapy with jejunal levodopa, subcutaneous apomorphine, or STN DBS and also measured the motor changes produced by an additional standard morning dose of levodopa. Motor performance was assessed with the UPDRS‐III, hand taps, the AIMS dyskinesia score and patients’ diaries. Outcome measures were time to best motor ‘on’ after start of morning treatment, daytime variability of motor condition, motor scores.

Results:  The time to ‘on’ was longest in the jejunal levodopa group. DBS and jejunal levodopa treatments produced stable motor conditions without appreciable ‘off’ episodes. Continuous apomorphine infusion was associated with the worst motor scores (UPDRS‐III and taps) and the most frequent off‐states. Jejunal levodopa infusion was associated with the highest AIMS scores. Addition of a levodopa dose produced shortening of time to ‘on’ and a transient motor improvement in the jejunal levodopa group without increase in dyskinesias; in the DBS and apomorphine groups, there was an increase in dyskinesias without changes in UPDRS‐III or taps.

Conclusions:  STN DBS provided adequate trade‐off between motor improvement and dyskinesia control, although dyskinesias could be elicited by adding oral levodopa. Jejunal levodopa infusion produced adequate motor improvement with slow time to ‘on’ and moderate dyskinesias. Apomorphine infusion produced insufficient motor control and negligible dyskinesias.
Cerebrotendinous xanthomatosis in Spain: clinical, prognostic, and genetic survey
Authors: Pilo‐de‐la‐Fuente B. , Jimenez‐Escrig A. , Lorenzo J. R. , Pardo J. , Arias M. , Ares‐Luque A. , Duarte J. , Muñiz‐Pérez S. , Sobrido M. J.
Published: June 2011

Background and purpose:  Cerebrotendinous xanthomatosis (CTX) is a rare autosomal recessive disorder caused by mutations in the CYP27A1 gene resulting in sterol‐27‐hydroxylase deficiency. Current information about CTX is based mainly on case reports, with only few large series reported. Although perceived as a potentially treatable condition, efficacy of chenodeoxycholic acid plus statin therapy remains unclear. To perform a nationwide survey of confirmed cases, with a thorough analysis of genotype‐phenotype data and prognostic factors.

Methods:  Retrospective review of the clinical and epidemiological aspects and mutations of all the patients diagnosed since 1992 in the main reference centers for genetic testing of CTX in Spain.

Results:  Twenty‐five patients from 19 families were identified. An average delay of 19 years was observed between symptom onset and clinical diagnosis. Two main clinical subgroups were recognizable: a classic form (cerebellar and other supratentorial symptoms) and a spinal form (chronic myelopathy). Cholestanol levels did not correlate with clinical presentation, severity or response to therapy. Despite treatment, five patients died during follow‐up, one to 4 years after diagnosis. Thirteen different mutations were identified, with a higher frequency of p.R395C in Northwestern Spain and p.R405W in Southern Spain. None of the mutations could be associated with a particular clinical feature combination or prognosis.

Conclusions:  This is the first nationwide extensive series of CTX reported in Spain. The higher number of cases in some areas suggests a possible founder effect. Spinal forms had a less severe prognosis. A delayed diagnosis could contribute to the lack of significant response to treatment.
Periventricular and deep white matter leukoaraiosis have a closer association with cerebral microbleeds than age
Authors: Yamada S. , Saiki M. , Satow T. , Fukuda A. , Ito M. , Minami S. , Miyamoto S.
Published: June 2011

Background:  Taking an advantage of the high sensitivity of 3D T2*‐weighted gradient‐recalled‐echo (GRE) imaging to cerebral microbleeds, we investigated the relationship between cerebral microbleeds and leukoaraiosis.

Methods:  Participants aged 40 years or more have been evaluated for the presence of cerebral microbleeds using 3D T2*‐GRE sequence since 2006. The severity of periventricular hyperintensity (PVH) and deep white matter hyperintensity (DWMH) on fluid attenuated inversion recovery images was assessed using Fazekas rating scales. Multivariate logistic regression analyses were conducted after adjustment for stroke subtype, age, PVH, DWMH, hypertension, dementia, and use of platelet aggregation inhibitors. Additionally, we examined the association between cerebral microbleeds and other covariates using a Pearson’s correlation analysis.

Results:  Amongst 389 patients, 67 patients had a single microbleed and 93 had multiple microbleeds. The prevalence of microbleeds was 83% amongst 53 patients with intracerebral hemorrhage (ICH), 49% amongst 173 with infarction, and 20% amongst 163 without any type of stroke. In the multivariate analyses, the odds ratio (95% CIs) of microbleed detection was 10.1, (4.12–24.8) for ICH, 2.33 (1.12–4.85) for atherosclerotic infarction, 1.66 (1.10–2.48) for PVH, and 1.49 (1.02–2.19) for DWMH. In the Pearson’s correlation analysis, cerebral microbleeds were closely related to PVH (Pearson’s correlation coefficient; 0.48) and DWMH (0.37), compared with age (0.16).

Conclusions:  High‐grade PVH, high‐grade DWMH, ICH, and atherosclerotic infarction were significantly independent predictors for cerebral microbleeds. In addition, we found that the grades of PVH and DWMH have a closer association with the number of cerebral microbleeds than age.
Low risk of vascular events following urgent treatment of transient ischaemic attack: the Aarhus TIA study
Authors: Weitzel‐Mudersbach P. v. , Johnsen S. P. , Andersen G.
Published: June 2011

Background and purpose:  Patients with TIA have a high short‐time risk of stroke and an increased long‐term risk of ischaemic vascular events compared with the general population. Urgent intervention may reduce short‐time stroke risk, but little is known about the effect beyond 3 months. We examined 1‐year outcome and risk factor management in patients with TIA after urgent intervention.

Methods:  All patients with TIA referred to Aarhus University Hospital 1 March 2007–28 February 2008 were seen by an acute TIA team (ATT), integrating outpatient care and stroke unit facilities. Preventive treatment was initiated immediately, including fast‐track surgery for carotid stenosis. Follow‐up including nurse‐conducted health counseling was carried out after 7, 90, and 365 days.

Results:  A total of 306 patients were included. Stroke, myocardial infarction, or vascular death occurred in 5.2% during 1 year of follow‐up. The cumulated stroke rate was 1.6%, 2.0%, and 4.4% after 7, 90, and 365 days, respectively, compared to expected 4.5% [relative risk (RR) 0.36, 95% CI 0.13–0.98] and 7.5% (RR 0.26, 95% CI 0.11–0.63) after 7 and 90 days using ABCD2 criteria. Recurrent TIA occurred in 10.2% (n = 32). Secondary prevention targets were attained in 47.6% after 1 year. Carotid surgery was performed in 8.1%; median time to operation was 11 days after contact with the ATT.

Conclusion:  Urgent intervention after TIA by an ATT covering outpatient and stroke unit facilities combined with nurse‐conducted health counseling is associated with a low 1‐year risk of new vascular events and may improve risk factor control.
The Dynamics of Multifaceted Gentrification: A Comparative Analysis of the Trajectories of Six Neighbourhoods in the Île‐de‐France Region
Authors: PATTARONI LUCA , KAUFMANN VINCENT , THOMAS MARIE‐PAULE
Published: June 2011

In this article, we propose to examine the diversity of ‘gentrification’ trajectories taken by six neighbourhoods in the Île‐de‐France Region. To apprehend the dynamics of the different gentrification processes, we investigate the manner in which changes in the urban environment render it accessible to certain residential aspirations and lifestyles and inaccessible to others. Our findings, based on a combination of a quantitative survey and socio‐historical analyses of six inner‐city and suburban neighbourhoods, suggest that ongoing gentrification largely depends on ways in which newcomers are able to maintain their lifestyle, and consequently on the elements likely to disrupt this. Thwarted gentrification, observed for example in the Goutte d'Or, can only be understood if we consider the not inconsiderable difficulties of daily life in such neighbourhoods and the relatively low level of social tolerance of newcomers. Static analyses attentive only to the structure of the property market do not account for the nuisances that, over time, make an environment intolerable and drive residents away. The dynamics of multifaceted gentrification relate, therefore, not only to the diverse structural characteristics of the various neighbourhoods but also to the differentiated — functional, social and sensitive — everyday experiences, perceptions and evaluations of the built environment.

Nous nous proposons d'examiner la diversité des trajectoires de gentrification de six quartiers d'Île‐de‐France. Pour appréhender la dynamique des différents processus de gentrification, nous analysons comment les changements opérés dans l'environnement urbain le rendent accessible à certaines aspirations résidentielles et certains modes de vie, et inaccessibles à d'autres. Combinant une enquête quantitative et une analyse socio‐historique des six quartiers (centraux et périphériques), nos conclusions suggèrent que la gentrification en cours dépend largement de la mesure dans laquelle les nouveaux habitants peuvent préserver leur mode de vie, et par conséquent, des facteurs susceptibles de perturber celui‐ci. La gentrification contrariée, observée par exemple à la Goutte d'Or, ne peut être appréhendée que si l'on tient compte des difficultés non négligeables de la vie quotidienne dans ces quartiers et de la tolérance sociale relativement faible des nouveaux arrivants. Les analyses statiques intéressées uniquement par la structure du marché immobilier n'expliquent pas les nuisances qui, avec le temps, rendent un environnement intolérable et poussent les habitants à déménager. Les dynamiques d'une gentrification à plusieurs visages sont donc liées non seulement aux diverses caractéristiques structurelles des quartiers, mais aussi aux évaluations, perceptions et expériences quotidiennes (fonctionnelles, sociales, sensorielles) différenciées de l'environnement construit.
Contracts and Learning in Complex Urban Projects
Authors: VAN DER VEEN MENNO , KORTHALS ALTES WILLEM K.
Published: June 2011

Complex urban projects developed within a neoliberal context may entail inclusionary goals. In order to recognize diversity and as a response to many uncertainties, learning during their realization becomes an important issue. Consequently, legal agreements for complex urban projects that cater to learning are more suitable than agreements in which detailed agreements are stipulated far in advance. This article presents a study of learning and contracting in four focal projects that were part of three complex urban projects: Battery Park City (New York), King's Cross (London) and the Zuidas project (Amsterdam). The agreements concluded in these projects cater to learning in very different ways, though the actual culture in the projects differs to a lesser degree.

Les projets urbains complexes élaborés dans un cadre néolibéral peuvent comporter des objectifs d’intégration. Pour prendre conscience de la diversité et en réaction à de nombreuses incertitudes, il devient essentiel d’apprendre au cours de la réalisation de ces projets. Par conséquent, les contrats juridiques concernant des projets urbains complexes qui pourvoient à cet apprentissage sont plus pertinents que ceux dans lesquels les accords sont spécifiés en détail très à l’avance. Cet article présente une étude de l’apprentissage et de la relation contractuelle concernant quatre projets pivots intégrés dans trois projets urbains complexes: Battery Park City (New York), King's Cross (Londres) et le projet Zuidas (Amsterdam). Les contrats conclus dans ces cadres pourvoient très différemment à l’apprentissage, bien que la culture propre à chaque projet ne soit pas si éloignée.
Recreative City: Amsterdam, Vehicular Ideas and the Adaptive Spaces of Creativity Policy
Authors: PECK JAMIE
Published: June 2011

The article presents a critical analysis of the reception and ramifications of creativity policies in the city of Amsterdam. The point is not to revisit critiques of creative cities policies per se, but rather to trace their consequences for the politics of urban governance — in one of their more receptive, if not ‘natural’, settings. The article explores how creativity policies actually work (and for whom) from the vantage point of one of Europe's most celebrated ‘creative cities’. It seeks to explain the persistence of the creativity syndrome — and the longevity, ubiquity and adaptability of the associated policy package — in the face of both social‐scientific skepticism and mediocre ‘performance’. Finally, it raises the question of how, and with what effects, creativity policies travel between cities; how they mutate in interurban space.

Cette analyse critique s'intéresse à la réception et aux ramifications des politiques publiques axées sur la créativitéà Amsterdam. Il ne s'agit pas de réexaminer les critiques sur les politiques des villes créatives en elles‐mêmes, mais de repérer leurs conséquences sur les politiques de gouvernance urbaine, dans l'un de leurs cadres le plus réceptif, pour ne pas dire ‘naturel’. Le but est d'étudier comment (et pour qui) les politiques liées à la créativité fonctionnent réellement, vu de l'une des ‘villes créatives’ les plus renommées d'Europe. Il convient d'expliquer la persistance du syndrome de créativité— ainsi que la longévité, l'ubiquité et l'adaptabilité du train de mesures politiques associées — malgré le scepticisme des sciences sociales et un niveau de ‘performances’ médiocre. Est ensuite amené un questionnement sur la manière dont les politiques propres à la créativité sont transposées d'une ville à l'autre, sur les effets de cette transposition, et donc sur les mutations qu'elles subissent dans l'espace interurbain.
Hypopyon‐like features: new dermoscopic criteria in the differential diagnosis of cutaneous lymphangioma circumscriptum and haemangiomas?
Authors: Gencoglan G. , Inanir I. , Ermertcan A.T.
Published: June 2011

Background  Lymphangiomas are congenital malformations of the lymphatic system characterized by clusters of translucent vesicles. Dermoscopically, yellow and bluish lacunea according to the lymphatic or haematic content were described previously, but it is difficult to distinguish them from haemangioma.

Observations  In nine patients with cutaneous lymphangioma circumscriptum (CLC), hypopyon‐like features were observed. None of the 10 patients with haemangioma had this finding.

Conclusion  Hypopyon‐like features can be a useful dermoscopic pattern in differentiating CLC from haemangioma.
The diagnosis of early psoriatic arthritis in an outpatient dermatological centre for psoriasis
Authors: Bonifati C. , Elia F. , Francesconi F. , Ceralli F. , Izzi S. , Solivetti F.M. , De Mutiis C.
Published: June 2011

Background  Most of the data currently available on early psoriatic arthritis (EPsA) derive from studies performed in rheumatological settings. However, in recent years, there has been an increase in the amount of data from dermatologic centres.

Objectives  To describe the prevalence, clinical, laboratory and imaging characteristics of psoriatic patients with EPsA seen at a dermatological outpatient psoriasis centre.

Methods  From January 2007 to May 2010, all patients with psoriasis who visited the psoriasis centre were asked about inflammatory joint involvement. A diagnosis of psoriatic arthritis was made on the basis of clinical, laboratory and imaging studies. The patients were diagnosed with early PsA (EPsA) if their inflammatory articular symptoms had been present for ≤1 year.

Results  We diagnosed EPsA in 33 patients. Joint involvement was polyarticular (>5 joints involved) in 20 patients (60.6%) and oligoarticular (≤5 joints involved) in the remaining 13 patients. Quality of life due to skin involvement and the degree of functional impairment due to joint inflammation were only mildly affected, as measured by DLQI and HAQ, respectively. A direct correlation between the number of tender joints (ACR 68) and HAQ was found (r = 0.36; P = 0.04). Imaging studies showed that in spite of the absence of radiologic findings of peripheral joint damage, ultrasonography and contrast enhanced ultrasonography showed signs of articular inflammation in all patients.

Conclusions  A diagnosis of EPsA can be correctly performed in a dermatologic outpatient facility. To do so, a close collaboration among dermatologists, rheumatologists and radiologists is necessary.