bluuebunny/crossref_metadata_2025_split huggingface dataset:
Misperception of Time-to-Collision by Drivers in Pedestrian Accidents
Authors: Stewart Douglas , Cudworth Christopher J , Lishman J R 
Published: January 2007

The approach of an object can be monitored from its optic flow. More specifically, it has been postulated that time-to-collision at constant velocity is perceived by relating visual angle θ to its rate of change θ̇, time-to-collision being θ/θ̇. This hypothesis is reappraised, and an alternative based on the parameters θ̇ and angular acceleration θ̈ is proposed. The expression 2 θ̇/θ̈ also specifies time-to-collision, with the benefits that it removes reliance on θ and permits time-to-collision to be determined from even momentary perception of an approaching point. This is supported by tests in which subjects responded to computer simulations of approaching objects. A further benefit is that if the object is accelerating rather than at constant velocity, time-to-collision is adjusted by 2 θ̇/θ̈, but not by θ/θ̇. As time-to-collision increases, however, its cognitive derivation should transfer from optic flow to separate perceptions of distance and speed. It is proposed that when drivers of road vehicles are in potential collision with pedestrians their perception of distance is based primarily on familiar size, resulting in overestimation of size and therefore of time-to-collision with child pedestrians. This is supported by further computer simulations and is corroborated by predicting the effect of that overestimation on certain types of accidents, then testing from national accident statistics. These analyses indicate that drivers' misperception of time-to-collision has a dramatic effect on the accident rate of child pedestrians. It is proposed that this could be greatly reduced by the provision of remedial measures.
Reference Repulsion When Judging the Direction of Visual Motion
Authors: Rauber Hans-Jürgen , Treue Stefan 
Published: January 2007

While humans are very reliable (ie give highly reproducible answers) when repeatedly judging the direction of a moving random-dot pattern (RDP) we find that their accuracy (ie the direction they so reliably report) shows systematic errors. To quantify these errors, we presented a complete set of closely spaced directions and mapped the directional misjudgments by asking subjects to compare the perceived direction of a moving RDP with the direction of a test line. The results show misjudgments of up to 9°, which are best accounted for by a tendency of the subjects to overestimate the angle between the observed motion and an internal reference direction. A control experiment in which subjects had to judge the spatial distance between a point and a line demonstrates that these misjudgments are not confined to motion stimuli but rather seem to reflect a general tendency to overestimate the distance between a stimulus and a reference when they are close to each other.
Diamond and biology
Authors: Nebel Christoph E , Shin Dongchan , Rezek Bohuslav , Tokuda Norio , Uetsuka Hiroshi , Watanabe Hideyuki 
Published: January 2007

A summary of photo- and electrochemical surface modifications applied on single-crystalline chemical vapour deposition diamond films is given. The covalently bonded formation of amine and phenyl linker molecular layers is characterized using X-ray photoelectron spectroscopy, atomic force microscopy (AFM), cyclic voltammetry and field-effect transistor characterization experiments. Amine and phenyl layers are very different with respect to formation, growth, thickness and molecular arrangement. We deduce a sub-monolayer of amine linker molecules on diamond with approximately 10% coverage of 1.5×10
15
cm
−2
carbon bonds. Amine is bonded only on initially H-terminated surface areas. In the case of electrochemical deposition of phenyl layers, multilayer properties are detected with three-dimensional nitrophenyl growth properties. This leads to the formation of typically 25 Å thick layers. The electrochemical bonding to boron-doped diamond works on H-terminated and oxidized surfaces.

After reacting such films with heterobifunctional cross-linker molecules, thiol-modified ss-DNA markers are bonded to the organic system. Application of fluorescence and AFM on hybridized DNA films shows dense arrangements with densities up to 10
13
cm
−2
. The DNA is tilted by an angle of approximately 35° with respect to the diamond surface. Shortening the bonding time of thiol-modified ss-DNA to 10 min causes a decrease in DNA density to approximately 10
12
cm
−2
. Application of AFM scratching experiments shows threshold removal forces of approximately 75 and 45 nN for the DNA bonded to the phenyl and the amine linker molecules, respectively. First, DNA sensor applications using Fe(CN
6
)
3−/4−
mediator redox molecules and DNA field-effect transistor devices are introduced and discussed.
Interactions of apomyoglobin with membranes: Mechanisms and effects on heme uptake
Authors: Vernier Grégory , Chenal Alexandre , Vitrac Heidi , Barumandzadhe Roya , Montagner Caroline , Forge Vincent 
Published: January 2007

AbstractThe last step of the folding reaction of myoglobin is the incorporation of a prosthetic group. In cells, myoglobin is soluble, while heme resides in the mitochondrial membrane. We report here an exhaustive study of the interactions of apomyoglobin with lipid vesicles. We show that apomyoglobin interacts with large unilamellar vesicles under acidic conditions, and that this requires the presence of negatively charged phospholipids. The pH dependence of apomyoglobin interactions with membranes is a two‐step process, and involves a partially folded state stabilized at acidic pH. An evident role for the interaction of apomyoglobin with lipid bilayers would be to facilitate the uptake of heme from the outer mitochondrial membrane. However, heme binding to apomyoglobin is observed at neutral pH when the protein remains in solution, and slows down as the pH becomes more favorable to membrane interactions. The effective incorporation of soluble heme into apomyoglobin at neutral pH suggests that the interaction of apomyoglobin with membranes is not necessary for the heme uptake from the lipid bilayer. In vivo, however, the ability of apomyoglobin to interact with membrane may facilitate its localization in the vicinity of the mitochondrial membranes, and so may increase the yield of heme uptake. Moreover, the behavior of apomyoglobin in the presence of membranes shows striking similarities with that of other proteins with a globin fold. This suggests that the globin fold is well adapted for soluble proteins whose functions require interactions with membranes.
Outcomes in occupational asthma caused by reactive dye after long‐term avoidance
Authors: Park H. ‐W. , Kim D. ‐I. , Sohn S. ‐W. , Park C. ‐H. , Kim S. ‐S. , Chang Y. ‐S. , Min K. ‐U. , Kim Y. ‐Y. , Cho S. ‐H. 
Published: January 2007

SummaryBackground
Reactive dye (RD) is known to be a causative agent of occupational asthma (OA). However, to date, no report has been issued concerning the long‐term outcomes of RD‐induced OA.Objectives
We sought to evaluate the long‐term outcomes in cases of OA caused by RD.Methods
A total of 11 OA patients confirmed by RD bronchial challenge were enrolled in this study. First and second follow‐up examinations were conducted at 4.3±2.3 and 13.7±2.3 years (means±SD) after the initial examinations, respectively. Skin prick test with RD and 11 common inhalant allergens, pulmonary function test, methacholine bronchial provocation testing, symptom and medication scores were determined at each visit. In addition, inflammatory cells in induced sputum were measured at the second follow‐up examinations.Results
Reduced lung function at initial examinations did not recover at the first and second examinations despite cessation of exposure and proper pharmacological treatment. In addition, asthma severity (as determined by symptom and medication scores) and non‐specific airway hyper‐responsiveness to methacholine also did not improve. However, skin reactivity to RD almost disappeared at the second examinations. Interestingly, four of the six patients who showed negative skin responses to all 11 common inhalant allergens at initial examinations were found to be atopic at the second examinations. Moreover, in terms of airway inflammation, seven of the 11 patients showed eosinophilia in induced sputum (3%) at the second examinations despite having been on high‐dose inhaled corticosteroid medication.Conclusion
The present study demonstrates that reduced lung function and asthmatic symptoms persist in RD‐induced OA even after long‐term exposure avoidance.
The functional heterogeneity of eosinophil cationic protein is determined by a gene polymorphism and post‐translational modifications
Authors: Trulson A. , Byström J. , Engström Å. , Larsson R. , Venge P. 
Published: January 2007

SummaryBackground
The eosinophil is a cytotoxic cell and takes part in parasite killing and tissue‐destructive processes by secretion of proteins such as eosinophil cationic protein (ECP). A polymorphism was demonstrated in the ECP gene, giving rise to a substitution of arginine at position 97 with threonine. This polymorphism is related to disease development.Objective
To investigate the functional and molecular heterogeneity of native ECP and the functional consequences of the replacement of arginine with a threonine.Methods
ECP was purified from healthy blood donors by gel filtration, ion‐exchange chromatography and reversed‐phase chromatography. Recombinant ECPs i.e. rECP 97arg and rECP 97thr were produced by the pFASTBAC baculovirus expression system. The cytotoxic activity was determined against an erythroleukaemia or a small cell lung cancer cell line.Results
Native ECP was purified to apparent homogeneity and showed a considerable molecular heterogeneity and a corresponding functional heterogeneity with respect to cytotoxic activity. After reduction, the native cytotoxic ECP showed three bands on sodium dodecylsulphate polyacrylamide gel electrophoresis : one major band at 18–20 kDa and two minor bands at about 10 and 5 kDa, respectively. The 5 kDa contained two masses differing with 56.2 Da, which corresponds to the difference in molecular masses of arginine and threonine. rECP 97arg was cytotoxic in contrast to rECP97thr. Deglycosylation with N‐glycosidase F did not affect the cytotoxic activity of native ECP to any measurable extent nor the activity of rECP 97arg, whereas rECP 97thr achieved cytotoxic activity. The RNase activities of the recombinant and native ECPs were similar.Conclusion
We conclude that ECP is present in several molecular forms with varying biological activities. Some of this functional heterogeneity is based on the genetic polymorphism of the ECP gene and some on post‐translational modifications. In subjects carrying the ECP 97thr variant, the cytotoxic activity may be disguised by N‐linked glycosylation of the active site.
Continued need of appropriate betalactam‐derived skin test reagents for the management of allergy to betalactams
Authors: Blanca M. , Romano A. , Torres M. J. , Demoly P. , DeWeck A. 
Published: January 2007

SummaryImmediate allergic reactions to betalactams (BLs) are due to IgE antibodies that recognize the ring‐derived penicilloyl determinant or side‐chain structures of common BLs. The presence of specific IgE antibodies can be demonstrated by skin testing, the determination of specific IgE antibodies in sera or their binding to basophils with subsequent activation upon contact with penicillinsin vitro. Skin tests are still the most sensitive technique followed byin vitrotests, which may sometimes yield useful complementary information. The diversity of the response to BLs has meant that in some instances, in addition to benzylpenicillin‐derived determinants, testing for amoxycillin, cephalosporins or other BLs may also be required to establish the diagnosis. The recent withdrawal from the market of BL‐derived materials for skin testing will have a serious effect on public health, resulting in a return to the pre‐1960 era before these reagents became available. Because of their greater sensitivity, these skin tests cannot yet be replaced byin vitrotests. Furthermore, skin tests are the most readily available form of allergy testing for physicians. This paper reviews the results of skin tests in BL allergy and provides evidence for their continued need.
Collection fluid helps preservation in voided urine cytology
Authors: Raistrick J. , Shambayati B. , Dunsmuir W. 
Published: January 2007

Objectives:  Degenerative change caused by delay in processing contributes to false‐negative and false‐positive diagnosis of urothelial carcinoma in cytology. The aim of the study was to see if the use of a collection fluid for urine samples made a significant difference to urine cytology diagnosis, and if one was better suited for routine use in the hospital laboratory. Three cell collection fluids were evaluated by analysing the preservation and degeneration of cells in urine samples, as was the routine preparation which did not use a collection fluid.Methods:  In the design study 50 voided urine specimens were taken at random from the hospital haematuria clinic. Three commercially available collection fluids cytolytTM, cytospin® and cytoRich®Blue and the hospital's routine conventional preparation of urine were compared. The degree of degeneration, and so preservation, was assessed by a table of chosen criteria; then ranked and analysed by Friedman's nonparametric test, at P = 0.05. A second table showing the cell content of each slide was also made.Results:  These showed no significant diagnostic difference between the collection fluids, but there was a significant difference between the collection fluids and the routine preparation. Minor differences that do not affect diagnosis, such as crystals and ghost red blood cells, were noted in cytospin® and cytoRich®Blue.Conclusion:  It is recommended that a collection fluid is used. This choice should be made after health and safety issues and cost are considered.
Laminin‐5 immunocytochemistry: a new tool for identifying dysplastic cells in oral brush biopsies
Authors: Driemel O. , Dahse R. , Hakim S. G. , Tsioutsias T. , Pistner H. , Reichert T. E. , Kosmehl H. 
Published: January 2007

Background:  The brush biopsy technique is not only a seminal technique but also a critically discussed method for detection of oral pre‐cancerous stages and manifest carcinomas. The γ2 chain of laminin‐5 and its proteolytic fragments comprise an invasion factor for many carcinomas.Objectives:  The aim of this study was to determine whether the immunocytochemical presentation of the laminin γ2 chain identifies pre‐invasive or invasive squamous cells in brush biopsies.Methods:  The value‐based identification of atypical epithelia was analysed in 93 consecutive brush biopsies with histopathological diagnoses: standardized haematoxylin and eosin staining; standardized immunocytochemistry: monoclonal antibodies against laminin γ2 chain: D4B5, 4G1, detection using ChemMate and Autostainer.Results:  Conventional cytology did not result in any false‐positive cases, i.e. atypical cells in normal, inflamed or benignly hyperproliferative mucosa (specificity, 100%), whereas immunocytochemistry revealed one false‐positive case (specificity, 98%). In brush biopsies of oral squamous cell carcinomas, the following immunocytochemical patterns were possible: (1) staining of the cytoplasm, (2) banded markings between clumped carcinoma cells and (3) positive hazes surrounding atypical cells. Bacterial colonies appeared as false‐positive results. Four of 27 carcinomas and one of three recurrences were not cytologically identified (sensitivity of conventional cytology, 79%). Three of the five carcinomas not identified by cytology were immunocytochemically stained with laminin γ2 chain antibody (sensitivity of laminin γ2 chain immunocytochemistry, 93%). The positive predictive value was 100% for conventional cytology and 97% for laminin γ2 chain immunocytochemistry. The negative predictive value attained was 92% for conventional cytology and 97% for laminin γ2 chain immunocytochemistry.Conclusions:  The high sensitivity level observed for method‐enhanced brush cytology suggests that this technique be used as an initial diagnostic step.
Social structure and facultative mating systems of hoary marmots (Marmota caligata)
Authors: KYLE C. J. , KARELS T. J. , DAVIS C. S. , MEBS S. , CLARK B. , STROBECK C. , HIK D. S. 
Published: January 2007

AbstractMate‐choice theory predicts different optimal mating systems depending on resource availability and habitat stability. Regions with limited resources are thought to promote monogamy. We tested predictions of monogamy in a social rodent, the hoary marmot (Marmota caligata), at the northern climatic extreme of its distribution. Mating systems, social structure and genetic relationships were investigated within and among neighbouring colonies of marmots within a 4 km2 valley near Kluane National Park, Yukon, Canada, using 21 microsatellite loci. While both monogamous and polygynous populations of hoary marmots have been observed in the southern reaches of this species’ range; northern populations of this species are thought to be predominantly monogamous. Contrary to previous studies, we did not find northern hoary marmot social groups to be predominantly monogamous; rather, the mating system seemed to be facultative, varying between monogamy and polygyny within, as well as among, social groups. These findings reveal that the mating systems within colonies of this species are more flexible than previously thought, potentially reflecting local variation in resource availability.
Clonal structure of Elytrigia atherica along different successional stages of a salt marsh
Authors: SCHEEPENS J. F. , VEENEKLAAS R. M. , VAN DE ZANDE L. , BAKKER J. P. 
Published: January 2007

Abstract Elytrigia atherica is a tall clonal grass species typical of higher salt marshes, but is gradually invading to the lower marshes. At young successional stages of a salt marsh, E. atherica is found sparsely dispersed in small groups of ramets. These patches increase in size and ramet density over time, eventually forming extensive swards as succession proceeds. This study investigates the change in the clonal diversity of E. atherica stands during colonization as a result of its reproductive strategy. Clonal diversities of differently sized patches of E. atherica were investigated on two lower salt‐marsh sites of different age, 25 years and 35 years, respectively. Microsatellite fingerprint patterns were used to determine genet identities and to estimate relatedness and genetic differentiation between the sites, between patches within sites and within patches. The majority of the patches on both sites contained more than one genet. On the older site, the clonal diversity was higher than on the younger site. However, the clonal diversity tended to decrease with increasing patch size. Low genetic differentiation was found between the two sites, indicating habitat differentiation, whereas differentiation between patches within sites was high. It is reasoned that different environmental conditions could have resulted in different clonal structures: On an older marsh, the increase of successful seedling recruitment, due to more suitable environmental conditions, leads to an increase in clonal diversity. Over time, with increasing ramet density, intraspecific competition is likely to increase, resulting in a decrease of clonal diversity.
Population decline despite high genetic diversity in the new allopolyploid speciesSenecio cambrensis(Asteraceae)
Authors: ABBOTT RICHARD J. , IRELAND HELEN E. , ROGERS HILARY J. 
Published: January 2007

AbstractSenecio cambrensis(Welsh groundsel) is a new allohexaploid species, which originated in Wales, UK, in the early part of the 20th century following hybridization between the native tetraploid groundsel (Senecio vulgaris) and the introduced diploid Oxford ragwort (Senecio squalidus). A survey of the number of populations and flowering individuals per population ofS. cambrensisin Wales was conducted at peak flowering time in June 2002, 2003 and 2004. The results show a dramatic decrease in both population number and population size of the species since the 1980s when the last population census was conducted. A survey of amplified fragment length polymorphism (AFLP) variation showed that this decline has occurred despite the fact thatS. cambrensiscontains a high level of genetic diversity with each individual screened possessing a unique multilocus phenotype. The level of variance within the species was similar to that found in one parent (S. vulgaris) and slightly greater than that among samples of the other parent (S. squalidus). Only a small proportion (5%) of AFLP diversity was partitioned among populations indicating a lack of population structure and possibly high levels of gene flow via seed dispersal in what is predominantly a selfing species.Senecio cambrensisshowed closer similarity in AFLP phenotype toS. vulgaristhan toS. squalidus. Possible causes of this and also the high level of AFLP diversity found inS. cambrensisare discussed. It is suggested that intergenomic recombination following occasional multivalent formation during meiosis inS. cambrensisis likely to be an important cause of both phenomena, although other causes are not ruled out.
Faulting on the western flank of Mt Etna and magma intrusions in the shallow crust
Authors: Mattia Mario , Patanè Domenico , Aloisi Marco , Amore Mauro 
Published: January 2007

AbstractSurface deformations on the western flank of Mt Etna volcano, spanning 1980–2004, have been analysed as they pertain to stress interactions between magma intrusions within the shallow crust along the S–SE Rift and faulting sensitivity. During this period, an accurate analysis of strain parameters, computed by inversion of SW electro‐optical distance data, suggested that the observed strong displacements on this flank of the edifice can also be related to dextral shear movements along a roughly NE–SW buried fault crossing the area covered by this network, as supported by seismic observations of the 20–24 April 2001 swarm. Moreover, Coulomb stress change model analysis confirms that the displacement along this fault, heralding the July–August 2001 eruption 2 months earlier can be related to major stresses applied by a dike intrusion at depth along the S–SE Rift, as testified by the microseismicity occurring between November 2000 and 19 April 2001.
Subsidence due to crack closure and depressurization of hydrothermal systems: a case study from Mt Epomeo (Ischia Island, Italy)
Authors: Sepe Vincenzo , Atzori Simone , Ventura Guido 
Published: January 2007

AbstractLevelling surveys carried out between 1990 and 2003 on the Mt Epomeo resurgent block (Ischia Island) record negative dislocations on its northern and southern flanks with a maximum subsidence rate of 1.27 cm yr−1. This deformation is not associated with the cooling, crystallization or lateral drainage of magma and cannot be explained by a pressure point or prolate ellipsoid source. Results from dislocation models and the available structural and geochemical information indicate that the subsidence is due to crack closure processes along two main ENE–WSW and E–W preexisting faults, which represent the preferred pathway of CO2 degassing from the hydrothermal system located beneath Mt Epomeo. The monitoring of the dislocations and CO2 flux along these faults could give useful information on the dynamics of the hydrothermal system.