bluuebunny/crossref_metadata_2025_split huggingface dataset:
Non‐parametric estimation and model checking procedures for marginal gap time distributions for recurrent events
Authors: Kvist Kajsa , Gerster Mette , Andersen Per Kragh , Kessing Lars Vedel 
Published: November 2007

AbstractFor recurrent events there is evidence that misspecification of the frailty distribution can cause severe bias in estimated regression coefficients (Am. J. Epidemiol 1998; 149:404–411; Statist. Med. 2006; 25:1672–1684). In this paper we adapt a procedure originally suggested in (Biometrika 1999; 86:381–393) for parallel data for checking the gamma frailty to recurrent events. To apply the model checking procedure, a consistent non‐parametric estimator for the marginal gap time distributions is needed. This is in general not possible due to induced dependent censoring in the recurrent events setting, however, in (Biometrika 1999; 86:59–70) a non‐parametric estimator for the joint gap time distributions based on the principle of inverse probability of censoring weights is suggested. Here, we attempt to apply this estimator in the model checking procedure and the performance of the method is investigated with simulations and applied to Danish registry data. The method is further investigated using the usual Kaplan–Meier estimator and a marginalized estimator for the marginal gap time distributions. We conclude that the procedure only works when the recurrent event is common and when the intra‐individual association between gap times is weak. Copyright © 2007 John Wiley & Sons, Ltd.
First‐trimester biochemical markers of aneuploidy and the prediction of small‐for‐gestational age fetuses
Authors: Spencer K. , Cowans N. J. , Avgidou K. , Molina F. , Nicolaides K. H. 
Published: November 2007

AbstractObjectivesTo examine the clinical utility of the first‐trimester biochemical markers of aneuploidy in their ability to predict subsequent delivery of a small‐for‐gestational age (SGA) infant.MethodsWe examined singleton pregnancies with no chromosomal abnormality and with complete outcome data that had undergone screening for trisomy 21 by a combination of fetal nuchal translucency (NT) thickness and maternal serum free β‐human chorionic gonadotropin (β‐hCG) and pregnancy‐associated plasma protein‐A (PAPP‐A) at 11 + 0 and 13 + 6 weeks' gestation. The biochemical markers were converted to multiples of the expected normal median (MoM) for a pregnancy of the same gestation. The association between free β‐hCG and PAPP‐A and the incidence of SGA were assessed by comparing the relative incidence at MoM cut‐offs and birth‐weight centile cut‐offs. At various marker levels the likelihood ratios (LR) for SGA were also calculated after excluding other adverse pregnancy complications.ResultsThere were 46 262 pregnancies resulting in live births with birth weight at or above the 10th centile, and 3539 below the 10th centile for gestation (SGA). There was a significant inverse association between the risk for SGA and maternal serum PAPP‐A MoM but not free β‐hCG MoM. At the 5th centile of the normal outcome group for PAPP‐A (0.415 MoM) the odds ratios for SGA below the 10th, 5th and 3rd centiles of normal were 2.70, 3.21 and 3.66 and the respective detection rates for SGA were 12.0%, 14.0% and 16.0%.ConclusionsLow levels of maternal serum PAPP‐A are associated, in the absence of an abnormal karyotype, with an increased risk for subsequent delivery of an SGA infant. Copyright © 2007 ISUOG. Published by John Wiley & Sons, Ltd.
A unification of probabilistic choice within a design-based model of reversible computation
Authors: Stoddart Bill , Zeyda Frank 
Published: November 2007

Abstract
We see reversible computing as a generalisation of sequential computation obtained by revoking the law of the excluded miracle. Our execution language includes naked guarded commands and non-deterministic choice. Choices which lead to miraculous continuations invoke reverse computation, and non-deterministic choice plays the rôle of provisional choice within a backtracking context. We require probabilistic choice for symmetry breaking and sampling large search spaces, but must formulate it differently from previous approaches to obtain the required interactions between probabilistic choice and non-deterministic choice and between probabilistic choice and feasibility. Our formulation allows us to derive the post-distributions which characterise a program, and we use these to construct a relational model. We consider refinement as containment of convex closures within distribution space, qualified with additional conditions to avoid over-refinement. We link the non-probabilistic and probabilistic versions of the model with a Galois connection and show that classical designs are a retract of our probabilistic designs. We consider the interaction between probabilistic and non-deterministic choice and find the same initially counter-intuitive results that have been noted by other investigators. We provide an alternative formulation, within the same model, of oblivious non-determinism, which allows all non-deterministic choices to be moved to the start of a computation. We consider the interaction between probabilistic choice and feasibility that is required to match an operational interpretation in which infeasible commands provoke reverse execution, and we present a small case study to show how the interaction between probabilistic choice and feasibility can be exploited in a practical program. All programming structures described here are supported by our implementation platform, the Reversible Virtual Machine, whose development has accompanied our theoretical investigations.
The role of exercise on the innate immunity of the elderly
Authors: Malaguarnera Lucia , Cristaldi Erika , Vinci Maria , Malaguarnera Mariano 
Published: November 2007

AbstractThe increased life span in human population has shown that some diseases, as infections, cancer and autoimmune phenomena, occur more frequently in the elderly than in the younger. We describe the ageing process involving the innate immune system and the improvement given by moderate physical activity. In addition, we discuss the altered neutrophil granulocytes function, the role of macrophages and natural killer cells, besides the influence of cytokines and secretory IgA. The acquired information help us to explain how these changes could favor the onset of diseases in the elderly and how they may boost their immune function.
Electron States and Light Absorption in Strongly Oblate and Strongly Prolate Ellipsoidal Quantum Dots in Presence of Electrical and Magnetic Fields
Authors: Dvoyan Karen G , Hayrapetyan David B , Kazaryan Eduard M , Tshantshapanyan Ani A 
Published: November 2007

Abstract
In framework of the adiabatic approximation the energy states of electron as well as direct light absorption are investigated in strongly oblate and strongly prolate ellipsoidal quantum dots (QDs) at presence of electric and magnetic fields. Analytical expressions for particle energy spectrum are obtained. The dependence of energy levels’ configuration on QD geometrical parameters and field intensities is analytically obtained. The energy levels of electrons are shown to be equidistant both for strongly oblate and prolate QDs. The effect of the external fields on direct light absorption of a QD was investigated. The dependence of the absorption edge on geometrical parameters of QDs and intensities of the electric and magnetic fields is obtained. Selection rules are obtained at presence as well as absence of external electric and magnetic fields. In particular, it is shown that the presence of the electric field cancels the quantum numbers selection rules at the field direction, whereas in radial direction the selection rules are preserved. Perspectives of practical applications for device manufacturing based on ellipsoidal quantum dots are outlined.
Wettability Switching Techniques on Superhydrophobic Surfaces
Authors: Verplanck Nicolas , Coffinier Yannick , Thomy Vincent , Boukherroub Rabah 
Published: November 2007

Abstract
The wetting properties of superhydrophobic surfaces have generated worldwide research interest. A water drop on these surfaces forms a nearly perfect spherical pearl. Superhydrophobic materials hold considerable promise for potential applications ranging from self cleaning surfaces, completely water impermeable textiles to low cost energy displacement of liquids in lab-on-chip devices. However, the dynamic modification of the liquid droplets behavior and in particular of their wetting properties on these surfaces is still a challenging issue. In this review, after a brief overview on superhydrophobic states definition, the techniques leading to the modification of wettability behavior on superhydrophobic surfaces under specific conditions: optical, magnetic, mechanical, chemical, thermal are discussed. Finally, a focus on electrowetting is made from historical phenomenon pointed out some decades ago on classical planar hydrophobic surfaces to recent breakthrough obtained on superhydrophobic surfaces.
Does smoking affect the quality of bone regenerate in paediatric limb reconstructive surgery?
Authors: Rajan Rohan Ananda , Ong Ming , Jones Stanley , Fernandes James 
Published: November 2007

Purpose To bring to the attention of the orthopaedic fraternity that adolescent children smoke and this has an adverse effect on the bone regenerate during limb deformity corrective surgery. Methods Retrospective review of patients undergoing limb deformity corrective surgery with a prolonged frame time and bone-healing index. Patients operated on between 1993 and 2005 in a single regional specialist paediatric orthopaedic hospital. Results Seventeen smoking patients (16 adolescent, one aged 9 years), with prolonged bone regenerate consolidation time of more than double the standard time. Bone-healing index (BHI) was increased in both active smokers and passive smokers. Conclusions In the older child/adolescent we should consider smoking (active or passive) as a detrimental factor in prolonging their frame times. We should council these patients and their carers to stop smoking at least during the period of their treatment.
Evaluation and improvement of sticky traps as monitoring tools for Glossina austeni and G. brevipalpis (Diptera: Glossinidae) in north-eastern KwaZulu-Natal, South Africa
Authors: Green K. Kappmeier , Venter G.J. 
Published: November 2007

AbstractThe attractiveness of various colours, colour combinations and sizes of sticky traps of the 3-dimensional trap (3DT), cross-shaped target (XT), rectangular screen (RT) and monopanels were evaluated for their efficacy to capture Glossina austeni Newstead and G. brevipalpis Newstead in north-eastern KwaZulu-Natal, South Africa. The 3-dimensional shapes of the XT and 3DT in light blue (l.blue) and white were significantly (ca. 3.1–6.9 times) better than the RT for G. austeni. On bicoloured XTs, G. austeni landed preferentially on electric blue (e.blue) (58%) and black (63%) surfaces when used with white; while for G. brevipalpis, significantly more landed on e.blue (60–66%) surfaces when used with l.blue, black or white surfaces. Increased trap size increased the catches of G. brevipalpis females and both sexes of G. austeni significantly. Temoocid and polybutene sticky materials were equally effective and remained durable for 2–3 weeks. The glossy shine of trap surfaces did not have any significant effect on the attraction and landing responses of the two species. The overall trap efficiency of the e.blue/l.blue XT was 23% for G. brevipalpis and 28% for G. austeni, and that of the e.blue/black XT was 16% for G. brevipalpis and 51% for G. austeni. Larger monopanels, painted e.blue/black on both sides, increased the catches of G. austeni females significantly by up to four times compared to the standard e.blue/black XT. This monopanel would be recommended for use as a simple and cost effective survey tool for both species in South Africa.
Temporal detection of Cry1Ab-endotoxins in coccinellid predators from fields ofBacillus thuringiensiscorn
Authors: Harwood J.D. , Samson R.A. , Obrycki J.J. 
Published: November 2007

AbstractThe area planted to genetically engineered crops has increased dramatically in the last ten years. This has generated many studies examining non-target effects of bioengineered plants expressingBacillus thuringiensisendotoxins. To date, most have focused on population-level effects in the field or laboratory evaluation of specific plant-herbivore or plant-herbivore-predator trophic pathways. Using a post-mortem enzyme-linked immunosorbent assay, we examined the uptake of Cry1Ab-endotoxins by predatory coccinellids and the importance of anthesis to this trophic pathway. AdultColeomegilla maculata,Harmonia axyridis,Cycloneda mundaandCoccinella septempunctatacontained low, but detectable, quantities of Bt-endotoxin when screened by ELISA. This was most evident inC. maculata, with 12.8% of 775 individuals testing positive for Cry1Ab-endotoxins. Interestingly, the presence of endotoxins in gut samples was not confined to periods around anthesis, but coccinellid adults tested positive two weeks before and up to ten weeks after pollen was shed, suggesting tri-trophic linkages in their food chain facilitates the transfer of endotoxins into higher-order predators. This contrasts with adultColeomegilla maculataentering overwintering sites where Bt-endotoxins were not detected in gut samples, indicating low levels of persistence of Cry1Ab-endotoxins within coccinellid predators. This study enhances our understanding of complex interactions between transgenic crops and non-target food webs, but further research is required to quantify the significance of specific trophic linkages in the field.
Suitability of two carbon dioxide-baited traps for mosquito surveillance in the United Kingdom
Authors: Hutchinson R.A. , West P.A. , Lindsay S.W. 
Published: November 2007

AbstractRapidly changing environments and an increase in human movement around the globe have contributed to a rise in new and emerging diseases, many of which are arthropod borne. The threat posed to the United Kingdom by such diseases is uncertain, and there is a real need to understand the distribution, seasonality and behaviour of potential vectors in the country. At present, there is no standard method for routine mosquito surveillance in the UK. Here we compared the catching efficiency of two carbon dioxide-baited traps, the CDC light trap and the MosquitoMagnet®Pro trap, for collecting British mosquitoes. Two of each type of trap were operated at four sites in central and southern England from June to September, 2003. To determine whether trap height affected collections, three light traps were operated at 1, 2.5 and 5 m above the ground in one site in 2004. Both types of trap were efficient at catching mosquitoes, collecting 5414 mosquitoes of 16 species. MosquitoMagnet®traps caught 2.7 times more mosquitoes than CDC light traps (P<0.001) and a wider range of species (16 species vs 11) than CDC light traps. Four to six times more femaleCulex pipienss.l. were collected in light traps at 5 m (P<0.001) compared with traps at lower heights. MosquitoMagnet®traps ran continuously for up to 8 weeks, whilst the battery of a CDC light trap had to be replaced every 24 hrs. Although MosquitoMagnets®collected more specimens and a greater range of mosquito species, they were considerably more expensive, prone to breakdown and incurred higher running costs than the CDC light traps. MosquitoMagnets®are useful tools for collecting mosquitoes during longitudinal surveys during the summer months, whilst CDC light traps are to be preferred for rapid assessments of the presence or absence of mosquitoes, particularly the important speciesCulex pipiens.
Population structure of the banana weevil, an introduced pest in the Canary Islands, studied by RAPD analysis
Authors: Magaña C. , Beroiz B. , Hernández-Crespo P. , Montes de Oca M. , Carnero A. , Ortego F. , Castañera P. 
Published: November 2007

AbstractThe banana weevil (BW),Cosmopolites sordidus(Coleoptera: Curculionidae), is one of the most important insect pests of bananas and plantains. The mobility and the origin of BW infestations at the Canary Islands (Tenerife, La Gomera and La Palma) have been analysed using Random Amplified Polymorphic DNA (RAPD) as molecular markers. Populations from Costa Rica, Colombia, Uganda and Madeira were also included for comparison. One hundred and fifteen reproducible bands from eight primers were obtained. The level of polymorphism in the populations from the Canary Islands (40–62%) was in the range of those found in other populations. Nei's genetic distances, pair-wise fixation index (FST) values indicate that the closest populations are Tenerife populations among themselves (Nei's genetic distance=0.054–0.100;FST=0.091–0.157) and Costa Rica and Colombia populations (Nei's genetic distance=0.049;FST=0.113). Our results indicate the existence of BW local biotypes with limited gene flow and affected by genetic drift. These results are compatible with a unique event of colonization at Tenerife; whereas, the outbreaks in La Gomera and La Palma may come from independent introductions. The Madeira population is phylogenetically and geographically closer to the Canary Islands populations, suggesting that it is the most likely source of the insects introduced in the Canary Islands.
Predicting the spatial distribution of Ochlerotatus albifasciatus (Diptera: Culicidae) abundance with NOAA imagery
Authors: Gleiser R.M. , Gorla D.E. 
Published: November 2007

AbstractOchlerotatus albifasciatus is a vector of western equine encephalomyelitis in Argentina and a nuisance mosquito affecting beef and dairy production. The objective of this study was to analyze whether environmental proxy data derived from 1 km resolution NOAA-AVHRR images could be useful as a rapid tool for locating areas with higher potential for Oc. albifasciatus activity at a regional scale. Training sites for mosquito abundance categories were 3.3×3.3 km polygons over sampling sites. Abundance was classified into two categories according to a proposed threshold for economic losses. Data of channels 1, 2, 4 and 5 were used to calculate five biophysical variables: normalized differences vegetation index (NDVI), land surface temperature, total precipitable water, dew point and vapour saturation deficit. A discriminant analysis correctly classified 100% of the areas predicted to be above or below the economic threshold of 2500 mosquitoes per night of capture, respectively. Components of the NDVI, the total precipitable water and the dew point temperature contributed most to the function value. The results suggest that environmental data derived from AVHRR-NOAA could be useful for rapidly identifying adequate areas for mosquito development or activity.
Ground beetle (Coleoptera: Carabidae) inventories: a comparison of light and pitfall trapping
Authors: Liu Y. , Axmacher J.C. , Li L. , Wang C. , Yu Z. 
Published: November 2007

AbstractCarabid inventories gained via pitfall trapping were compared to manual samples from light towers. A comparison of the two methods indicated that pitfall traps recorded a significantly higher diversity of carabids and were efficient in indicating changes of habitat conditions. Nevertheless, this method failed to give near-complete inventories of all carabid species present. Manual sampling at light towers resulted in far greater sample sizes, and this method was particularly efficient in monitoring potential pest species, but again failed to record all species present. Both methods hence showed different strengths, and only a combination, potentially also including further sampling techniques, will enable the generation of complete species inventories.
Long-term patterns and feeding sites of southern green stink bug (Hemiptera: Pentatomidae) in Hawaii macadamia orchards, and sampling for management decisions
Authors: Wright M.G. , Follett P.A. , Golden M. 
Published: November 2007

AbstractSouthern green stink bug (Nezara viridula, Hemiptera: Pentatomidae) is a pest of macadamia nuts, causing pitting to kernels by feeding. In spite of its pest status, many aspects of the ecology of this insect in macadamia orchards are poorly understood. This study analyzes long-term N. viridula damage to macadamia nuts and investigates the extent to which damage to nuts occurs in the tree canopy, prior to nut-drop. We show that there are distinct seasonal peaks in damage detected after harvest and that, over six years of data collection, mean damage levels were fairly low, albeit with spikes in damage levels recorded. Sampling nuts at peak harvest periods from different strata in the trees and from the ground showed that incidence of damaged nuts within the canopy was typically half as high as on the fallen nuts. Damage to fallen nuts may have occurred prior to nut-drop, and continued to accumulate after nut-drop. These results show that management of N. viridula within macadamia canopies, as opposed to only on fallen nuts, is important. A sampling procedure and predictive model for estimating late-season damage based on early-season damage samples is provided. The model uses January and March damage measurements (based on samples with set level of accuracy), mean temperature and month of the year for which damage is predicted. Early-season damage of 6–10% predicts late-season damage levels that should justify N. viridula suppression based on the nominal threshold (13% damage) used by kernel processors to reject nuts based on damage.
Relative developmental and reproductive fitness associated with pyrethroid resistance in the major southern African malaria vector,Anopheles funestus
Authors: Okoye P.N. , Brooke B.D. , Hunt R.H. , Coetzee M. 
Published: November 2007

AbstractThe effect of pyrethroid resistance on the fitness of a laboratory strain ofAnopheles funestusoriginating from southern Mozambique was evaluated by comparing the developmental and reproductive characteristics of a pyrethroid resistant strain with an insecticide susceptible strain. Fitness was evaluated in terms of fecundity, fertility, egg production, developmental time and life stage progression and survival. Of the eggs laid by females of the resistant strain, 81.5% hatched while only 66.9% were recorded in the susceptible strain. The time from egg hatch to adult emergence was longer for the resistant strain (15.9 days) than the susceptible strain (15.2 days). A significantly higher proportion of eggs from the resistant strain (61.6%) survived to adulthood compared with those of the susceptible strain (49%). Fecundity and larval and pupal survival did not differ significantly between strains. Of spermathecae dissected from females of the resistant strain, 56.8% were fertilized compared to 52.6% from the susceptible strain. The proportion of females that successfully produced eggs was 43.3% and 23.3% for the resistant and susceptible strains respectively. Complete failure of larval hatch was recorded in 28.6% of susceptible strain families compared to 7.7% of resistant families. Our results show that pyrethroid resistance in southern AfricanAn. funestusdoes not incur any loss of fitness under laboratory conditions. These results suggest that the removal of pyrethroid insecticide selection pressure may not lead to a regression of resistance alleles in pyrethroid resistantAn. funestuspopulations in southern Africa.