bluuebunny/crossref_metadata_2025_split huggingface dataset:
Experimental phase equilibria constraints on pre‐eruptive storage conditions of the Soufriere Hills magma
Authors: Barclay J. , Rutherford M. J. , Carroll M. R. , Murphy M. D. , Devine J. D. , Gardner J. , Sparks R. S. J. 
Published: September 2002

New experimental results are used to constrain the P, T, X(H2O) conditions of the Soufriere Hills magma prior to ascent and eruption. The experiments were performed on a powdered andesite erupted in January, 1996, at an fO2 corresponding to ∼NNO+1 with PH2O and temperatures in the range 50 to 200 MPa and 800 to 940°C. Amphibole is stable at PH2O >115 MPa and temperatures <875°C. Quartz only becomes stable at low temperatures and after high degrees of crystallization (T <840°C, >72 wt% SiO2 in residual melt) at PH2O >115 MPa. Analyses of rhyolitic glass inclusions in quartz and plagioclase from recently erupted samples indicate melt water contents of 4.27±0.54 wt% H2O and CO2 contents <60 ppm. The evolved Soufriere Hills magma would therefore be H2O‐saturated at pressures <130 MPa.These results suggest that the Soufriere Hills magma containing the stable assemblage amphibole, quartz, plagioclase, orthopyroxene, magnetite and ilmenite was stored at PH2O of 115‐130 MPa, equivalent to a minimum depth for a water‐saturated magma chamber of 5–6 km depth. Magma temperatures were initially low (820–840°C). Quartz is believed to have been destabilised by a heating event involving injection of new basaltic magma. The stability field of hornblende provides a useful upper limit (∼880°C) for the extent of this reheating.
Dispersionless injection simulations explore auroral substorm origins
Authors: Li Xinlin , Baker D. N. , Temerin M. , Reeves G. D. , Belian R. D. 
Published: September 2002

The “driving engine” of auroral substorms is rather far out in the magnetotail and then propagates inward, a recent study suggests. The results are based on test particle simulations of dispersionless particle injections and indicate an origin distance of more than 15 Earth radii (RE) away (1 RE = 6380 kilometer). The work is also showing how such dispersionless injections can, in principal, be produced.Dispersionless particle injection is one of the characteristic features of substorm onset and refers to the sudden appearance of energetic ions and electrons over a broad range of energies (tens to hundreds of keV) in the Earth's magnetosphere. Such injection events are often seen near midnight on satellites in geosynchronous orbit in association with substorm onset.
Ocean management plan includes array of recommendations
Authors: Showstack Randy 
Published: September 2002

When U.S. President Bill Clinton and Vice President Al Gore appeared in Monterey, California in June 1998 for a National Oceans Conference, some of the salt water spray from the Pacific Ocean must have clung to them.As a follow‐up to the conference, the Clinton Administration on September 2 issued an interagency report to help guide federal efforts in establishing a comprehensive ocean policy.The report, which touches upon a number of global issues including the United Nations Convention on the Law of the Sea, contains nearly 150 recommendations.
Outstanding student paper awards
Authors: Anonymous  
Published: September 2002

The Space Physics & Aeronomy Section presented seven outstanding student paper awards at the 1999 Spring Meeting in Boston, Massachusetts, last June.Jerry Goldsteinpresented a paper titled “Simulation and Detection of Plasmaspheric Cavity Modes.” Jerry received a B.S. in physics from Brooklyn College in 1993. He is presently at Dartmouth College working toward completion of his Ph.D. under the direction of Professor Mary Hudson. Before coming to Dartmouth, Jerry participated in theoretical quantum mechanics research at Penn State, and instrumentation development at Brookhaven National Laboratory Jerry's current research is an observational/numerical study of ULF cavity mode resonances in the plasmasphere and outer magnetosphere. Using an MHD wave simulation code that incorporates in situ electron density measurements to specify a background plasma density, Jerry has been examining electric and magnetic field observations made by the Polar and CRRES satellites for evidence of cavity modes. He has also been working on a simple analytical MHD wave model of the magnetospheric cavity, in order to study wave leakage and ionospheric Joule heating effects due to realistic boundary conditions.
Outstanding student paper awards
Authors: Anonymous  
Published: September 2002

The Ocean Sciences Section presented three outstanding student paper awards at the 1999 AGU Spring Meeting in Boston, Mass., last JuneSusan C. Bates presented a paper titled “The Effect of Subsurface Temperature Variability on the Predictability of Tropical Atlantic SST.” Susan obtained her bachelor of science degree in geology at Duke University while focusing on coastal/barrier island processes. After receiving her degree in 1995, she worked for 2 years as a geologist for an environmental consulting company in Raleigh, North Carolina. She is currently pursuing a master's degree at Texas A&M University under the advisement of Ping Chang. Although her research focuses on statistical analysis of tropical Atlantic SST, she is also interested in the broader topic of the effect of ocean processes on global climate and local/regional weather phenomena.
A novel system for the objective classification of iris colour and its correlation with response to 1% tropicamide
Authors: German Emma J. , Hurst Mark A. , Wood Diana , Gilchrist Jim 
Published: September 2002

SummaryIris colour can provide an enormous amount of information about an individual. In addition to changes with pathological conditions, the colour of the iris can be a particularly useful indicator of how well a person will respond to a topically applied ocular drug. Until recently, classification of iris colour has been subjective, ranging from a basic description (‘light’ and ‘dark’) to more detailed grading systems, such as a comparison with preset photographic standards. However, variability within observers and differences in the interpretation between observers can influence the results. Objective techniques, in this respect, possess several advantages. They are able to detect differences in colour that subjective techniques are incapable of and they provide continuous data rather than discrete categories, thus improving the accuracy of drug response predictions. This study assessed iris colour by objective means. Slit‐lamp photographs of various coloured irides were taken under standardised conditions. The slides were then scanned into a computer and the colour analysed using a calibrated software package. To establish the optimum colour parameter to be used for predictions of drug response, several parameters were calculated and compared with the subject response to 1% tropicamide (maximum change in pupil size, time to maximum change and total duration of effect). Many parameters had strong correlations with drug response, but the parameters ‘z’, ‘b’ (the proportion of blue in the image) and ‘y’ (the proportion of yellow in the image) were found to exhibit the highest correlations. They also showed better correlations with drug response than did a current iris colour grading system.
A study of the accuracy of lens measures
Authors: Hilton Owen , Obstfeld Henri 
Published: September 2002

SummaryThe accuracy of 26 aged and three new lens measures was investigated. Instruments were applied to surfaces of known curvature employing the conventional, hand‐held method as well as while rigged on an optical bench. In addition, using the latter method, a controlled amount of surface tilt was introduced. A large inter‐instrument variation in accuracy was encountered. In general, hand‐held lens measures were found to provide equally accurate measurements on convex and concave surfaces, with the exception of the −20 D surface, and inclinations from 0° to 5° did not result in erroneous measurements. Results for inclinations of 15° became unreliable. The different usages of the instrument are discussed.
The infant patient
Authors: McCulloch Daphne L. 
Published: September 2002

SummaryThe infant patient presents a challenge to the optometrist who must structure an examination within the infant's limited capabilities and then manage a rapidly developing visual system. The present paper provides an overview of infant visual development and the visually guided behaviours expected during normal development. Techniques for assessing vision in infant are reviewed and a recommendation is given for the optometric examination of infants. Some important urgencies, emergencies and causes of visual impairment are highlighted.
The influence of cognition and age on accommodation, detection rate and response times when using a car head‐up display (HUD)
Authors: Wolffsohn J. S. , McBrien N. A. , Edgar G. K. , Stout T. 
Published: September 2002

SummaryCar head‐up displays (HUDs), which portray information in the form of a virtual image reflected off a combiner, allow the viewing of complex information, such as route guidance, without the need for the driver to look away from the road ahead. The cognitive demand required by the HUD task may distract drivers from the outside world scene and cause reaction times to slow. Cognitive capacity also decreases with age. The aim of the present study was to determine the effect of cognitive demand and age on the use of a car HUD. Subjects (young, middle or older age drivers, each groupn=8) performed a HUD‐assisted driving task, with three levels of cognitive demand, whilst accommodation was simultaneously measured using a dynamically recording infra‐red optometer. Response times to, and the detection rate of, changes in both the HUD image and the outside world scene were analysed. Increasing the cognitive demand associated with the HUD image increased over‐accommodation (greatest in the young, 0.34±0.05 D,p<0.001). Response times to and detection of changes in the HUD image and outside world scene were significantly worse with increased cognitive demand. Response times to and detection of changes in the HUD image and outside world scene also increased with age. The implication of the results with respect to car HUD design and safety are discussed.
Imaging in the 21st century
Authors: Charman W. N. 
Published: September 2002

SummaryMethods which are likely to become increasingly common in the next century for producing images of the eye and related structures are briefly reviewed. Although techniques based on reflected visible light will continue to be of importance, improved versions of methods based on other physical principles will come into increasingly widespread use. Digital image recording will probably play a dominant role and it is concluded that a key feature that will be common to almost all the methods will be their capacity to provide quantitative data on the state of the eye.
Positional acuity in amblyopia: does a perceptual consequence of neural recruitment exist?
Authors: McGraw Paul V. , Winn Barry , Whitaker David , McFadzean Robert 
Published: September 2002

SummaryAnimal models of amblyopia have shown that visual deprivation for even brief periods can result in dramatic changes in cortical architecture. Active neural recruitment mechanisms present the possibility that the non‐deprived eye of amblyopes may show enhanced visual capacity. This idea was tested by measuring a form of positional acuity which we have termed alignment threshold. Three subject groups were examined, adults, visually normal children, and children with amblyopia in which the non‐deprived eye was tested. Alignment thresholds in adults were significantly better (∼0.3 log unit) than the thresholds for visually normal children. No significant difference was found in thresholds between the visually normal children and the non‐deprived eye of the amblyopic children. The results of this study suggest that subjects with unilateral amblyopia do not show enhanced visual alignment performance in their non‐deprived eye.
Intraocular pressure and pulse rate measurements by the OBF tonograph — comparison to reference instruments
Authors: Yang Y. C. , Illango B. , Cook A. , Batterbury M. 
Published: September 2002

SummaryThe purpose of this study was to evaluate the accuracy of intraocular pressure (IOP) and ocular pulse rate (OPR) measurements obtained by the Ocular Blood Flow (OBF) tonograph (OBF Labs, Wiltshire, UK). Measurements of IOP and OPR by the OBF tonograph were compared to those of reference instruments. For IOP evaluation, measurements were obtained on patients with normal and abnormal pressures using the OBF tonograph and the Goldmann applannation tonometer in random alternate order. For the OPR evaluation, measurements were obtained using the OBF tonograph with simultaneous heart rate monitoring by ECG on patients with normal IOP. The validity of the OBF tonograph measurements was quantified in terms of 95% limits of agreement and their relationships to measurements by reference instruments was determined by linear regression analyses. 102 patients were recruited for IOP measurements. Mean IOP obtained by the Goldmann tonometer was 20.7 mmHg (7–42 mmHg, SD 6.98) whilst mean IOP obtained by the OBF tonograph was 20.1 mmHg (8.1–40.2, SD 6.1). Goldmann IOP and OBF tonograph IOP readings were well correlated (r=0.945). Analysis of the difference in IOP measurements between two instruments (tonograph minus Goldmann tonometer) showed the mean bias to be 0.26 mmHg (−7.8 to +6.1 mmHg) and the 95% limits of agreement to be −4.35 to +4.87 mmHg. Agreement between two instruments appeared to be dependent on the IOP; at IOP lower than 20.6 mmHg there was an overall tendency for the tonograph IOP to be higher than Goldmann IOP and vice versa when IOP was above 20.6 mmHg. 47 patients were recruited for OPR and ECG measurements. Mean pulse rates were 74.8 beats per min (mean 43–110) by ECG and 73.9 beats per min (43–110) by tonography. Analysis of the difference in pulse rate between instruments (tonograph OPR minus ECG pulse rate) against the average pulse rate showed the mean bias to be −0.8 beats and the 95% limits of agreement to be between −7 to +5 beats. Ocular pulse rate values obtained by the OBF tonograph were very accurate when compared to ECG pulse rate. This indicates that there is unlikely to be a systematic lag in continuous ocular pulse waveform recording. Intraocular pressure measurements by the OBF tonograph correlated very well with Goldmann readings over a wide range of pressures and should be valid in the clinical setting.
Response of the human visual system to variable illuminant conditions: An analysis of opponent‐colour mechanisms in colour constancy
Authors: Nieves J.L. , Garcı´a‐Beltrán A. , Romero J. 
Published: September 2002

SummaryIlluminant changes in a scene generally cause displacements in the chromaticity and luminance of the objects of which the scene is composed; however, the visual system is capable of maintaining a constant object colour appearance independently of the illuminant. This is the phenomenon traditionally known as colour constancy. A classical asymmetric colour‐matching experiment is reported to address two aspects of colour constancy: successive colour constancy and the role of opponent mechanisms in it. To this end, colour matches are made with chromatically complex backgrounds under different illuminants and with an equal‐energy light source as standard. The results are analysed in the cone‐excitation space, separately along the L‐2M and S dimensions.Data are presented showing that colour‐vision mechanisms respond differently to illuminant changes when colour constancy is considered at both receptoral and post‐receptoral levels. The L‐ and M‐cones tend to adapt so as to support colour constancy, whereas S‐cones are strongly influenced by the illuminant changes. In addition, the data suggest good approaches to colour constancy linked particularly to the yellow‐blue mechanism.
Accommodation microfluctuations and pupil size during sustained viewing of visual display terminals
Authors: Gray L.S. , Gilmartin B. , Winn B. 
Published: September 2002

SummaryAccommodation microfluctuations comprise two dominant frequencies; a low frequency component (LFC0.6 Hz) and a high frequency component (1.0 Hz<HFC<2.1 Hz). In the present experiment we examine accommodation microfluctuations and steady‐state pupil responses during sustained viewing of visual display terminals (VDTs). Steady‐state accommodation and pupil responses were measured continuously and simultaneously using a modified Canon Autoref R‐1 infra‐red objective optometer and an Hamamatsu C3160 Perceptscope Video Area Analyser. Measurements were obtained at three time intervals (0, 10 and 20 min) during a 20 min reading task presented on five different displays. With the displays placed at 50 cm, the task was to locate and identify typographical errors in one of five sets of standard text. Five young visually‐normal emmetropic subjects with a mean age of 22.5±3.0 years participated in the study. Two‐way ANOVA revealed no significant variation in the magnitude of the accommodation microfluctuations with either display or task duration, nor was there any significant interaction between these two factors. There was no significant variation in mean pupil diameter with either display or task duration. These measures may have the potential to provide objective information about visual display quality.
Astigmatism
Authors: Harris W.F. 
Published: September 2002

SummaryThe quantitative representation and analysis of astigmatism present difficulties for the researcher. The case is made that the difficulties arise because of the way astigmatism is conceived and defined. In most cases astigmatism is regarded as cylinder. Cylinder, however, is not invariant under spherocylindrical transposition and, hence, cannot strictly be regarded as meaningful. The purpose of the paper is to find a rational, context‐free, invariant and universally‐applicable definition of astigmatism for all quantitative analyses. One is led to definitions of astigmatism and its components some of which have already appeared in the literature but which are not in use in analyses of astigmatism. Astigmatism is defined with respect to pure sphere. In the case of thin systems (including keratometric measurements and refraction) astigmatism turns out to be Jacksonian power, that is, the power of a Jackson crossed cylinder. The power of every thin system can be regarded as consisting of two orthogonal components, sphere and astigmatism. The astigmatism of thin systems itself further decomposes naturally into two orthogonal components called ortho‐ and oblique astigmatism. In the case of thick systems, like the eye itself, astigmatism decomposes naturally into three orthogonal components, ortho‐, oblique and antisymmetric astigmatism. The approach is based on the general definition of power in paraxial optics, the dioptric power matrix, and leads to useful graphical representations. Because of its mathematical foundation the analysis can claim completeness and contextual independence. Furthermore it is also directly applicable to the four fundamental paraxial properties of optical systems.
EFFECT OF ODOUR CUES ON THE EXPLORATORY BEHAVIOUR OF FEMALE COMMON VOLES LIVING IN MATRIARCHAL GROUPS
Authors: Heise  , Rozenfeld  
Published: September 2002

AbstractSeven matriarchal breeding groups of common voles (Microtus arvalis) were studied to test bonding between females when given the option to leave their family group, and the hypothesis that they explore more in areas with odours from related individuals compared to areas scented with odours from unrelated individuals.Young females were observed more frequently in the proximity of their mother and were recorded more often with their sisters than alone. Except for reproductive females, all females were seen more frequently in the initial home area than in areas of exploration. Females frequented an area scented with the odour of related females more often than one with the odour of unrelated, unfamiliar females, but only shortly before dark. In most test groups only the adult females reproduced although their daughters had reached the age of sexual maturity. The results indicate that young female M. arvalis tend to stay with their mother and may delay their own reproduction. When exploring the vicinity of the burrow young females tend to prefer areas with the scent from related females and can recognize odour cues after being separated from the odour donor for 3.5 weeks. This behaviour may minimize aggressive encounters, leading to dispersal toward related individuals.
Fluorescence Spectral Patterns of α,ω-Diphenylpolyenes near the S1(21Ag) and S2(11Bu) Level Crossing Point in Solution
Authors: Itoh Takao 
Published: September 2002

Abstract
The changes of the fluorescence spectral patterns observed when the S2(11Bu) level is approached the S1(21Ag) level by varying the solvent polarizability have been investigated for all-trans-1,6-diphenyl-1,3,5-hexatriene (DPH) and all-trans-1,8-diphenyl-1,3,5,7-octatetraene (DPO) in room temperature solvents. It is shown that the emission of DPO in diiodomethane consists nearly of a 1 : 1 mixture of the S2 and S1 fluorescence and that the emission of DPH in CS2 consists almost entirely of the S2(11Bu) fluorescence. When the 11Bu level approaches the 21Ag level, not only the increase of the S2 fluorescence intensity but also the change in the spectral pattern of the S1 fluorescence are observed for DPH and DPO. The solvent polarizability that achieves the inversion of the 21Ag and 11Bu levels for DPO has been estimated to be 0.54.
Developing linguistic literacy: perspectives from corpus linguistics and multi-dimensional analysis
Authors: BIBER DOUGLAS , REPPEN RANDI , CONRAD SUSAN 
Published: September 2002

In their conceptual framework for linguistic literacy development, Ravid &
Tolchinsky synthesize research studies from several perspectives. One of
these is corpus-based research, which has been used for several large-scale
research studies of spoken and written registers over the past 20 years. In this
approach, a large, principled collection of natural texts (a ‘corpus’) is
analysed using computational and interactive techniques, to identify the
salient linguistic characteristics of each register or text variety. Three
characteristics of corpus-based analysis are particularly important (see Biber,
Conrad & Reppen 1998):[bull ] a special concern for the representativeness of the text sample being
analysed, and for the generalizability of findings;[bull ] overt recognition of the interactions among linguistic features: the ways
in which features co-occur and alternate;[bull ] a focus on register as the most important parameter of linguistic
variation: strong patterns of use in one register often represent only weak
patterns in other registers.