bluuebunny/crossref_metadata_2025_split huggingface dataset:
THE SOCIAL SECURITY CRISIS: AN INTERNATIONAL DILEMMA1
Authors: Fisher Paul 
Published: December 2007

Social security systems throughout the world are in a dilemma. The over‐expansion of the sixties has compounded the current recession's unemployment and other problems and created an “ideal” system difficult for the economically depressed countries to alter.Older workers are particularly hard hit during recessions. They are often pressured into retirement, with no financial or career alternatives, in an attempt to free up jobs for younger and hard‐to‐place workers. Many schemes have been devised to compensate older workers for their losses: high unemployment compensation, partial unemployment benefits and a liberal interpretation of disability insurance and other assistance programmes not specifically designed for the elderly.The author exposes many proposals for altering social security but concludes that most schemes have not yet been implemented. While international economic recovery would surely heal the ailing systems, the author contends there are remedial measures, largely ignored at present, that could be taken to soothe the systems' wounds.
CORNEAL TRANSPARENCY CHANGES RESULTING FROM OSMOTIC STRESS
Authors: Stevenson Ronald , Vaja Nat , Jackson Jonathan 
Published: December 2007

Abstract Corneal thickness and transparency changes were measured following exposure of the cornea to various levels of osmotic stress. Bathing the cornea in hypotonic solutions of NaCl caused an increase in corneal thickness and light scatter within the cornea.Transparency changes with hypotonicity were determined by comparing the relative brightness of haloes around a bright lamp source for the various concentrations of NaCl solutions. Corresponding corneal thickness changes were determined by pachometry.A nearly linear relationship was found between solution hypotonicity and the degree of corneal swelling, whilst an exponential relationship was found between hypotonicity and relative halo brightness. The rate of corneal recovery from osmotic stress was found to be constant with different degrees of tonicity, although the rate of thickness recovery was much slower than the recovery from haloes.
VARIATION OF SACCADIC SUPPRESSION WITH TARGET ECCENTRICITY
Authors: Osaka Naoyuki 
Published: December 2007

Abstract— Two LEDs separated by 24° from each other were employed as saccadic fixation sources located on a circle about the centre of the saccade path. Either horizontal, vertical or oblique saccade paths were used and a brief test flash was presented at one of five retinal eccentricities during each saccade. The percentage of detected flashes was measured as a function of the location of the test stimulus and of its time delay with respect to the onset of the saccade. The results suggest that saccadic suppression is maximal at the fovea and is significantly decreased as retinal eccentricity increases.Based on a paper presented at the 2nd European Conference on Eye Movements held at Nottingham, U.K. and supported in part by the Japanese Ministry of Education Grant #56510078 and the Yoshida Memorial Foundation Grant 17–9.
Criteria for decompensation in binocular vision
Authors: Jenkins T. C. A. , Pickwell L. D. , Yekta A. A. 
Published: December 2007

Two groups of patients, one under 40 years of age and the other 40 years and over, were divided into subgroups according to whether they had symptoms associated with near vision. A method developed in ‘signal detection theory’ was used to determine whether a value could be found for heterophoria, or associated heterophoria, which would predict which patients had symptoms due to decompensated heterophoria in normal routine investigation. Receiver operator characteristic curves (ROC curves) were constructed to look for these cut‐off values between patients with, and without, symptoms.No value for dissociated heterophoria was found that would discriminate between the symptomatic and asymptomatic patients. It is concluded that heterophoria measurement is not useful as a routine procedure. In the case of associated heterophoria, for the under 40 years age group, patients with a value of 1 prism dioptre or more are more likely to have symptoms than not, and one‐third of patients with close work problems have a value of 2 prism dioptres or more. It was rare to find any asymptomatic patient with a value as high as this. In the 40 years and over age group those with an associated heterophoria of 2 prism dioptres or more are more likely to have symptoms than not. One‐third of patients in the latter age group, with symptoms, have a value of 3 prism dioptres or more whilst it is rare to find an asymptomatic patient with a value as large as this.
Ageing parameters of the ocular lens by scanning fluorophotometry*
Authors: Hemenger Richard P. , Occhipinti Joseph R. , Mosier Marjorie A. 
Published: December 2007

A Beer‐Lambert analysis of fluorophotometric scans of ocular lenses has been carried out. It is shown that an assumption of a single flourophor allows us to calculate the distribution of this fluorophor along the central lens axis.For the great majority of lenses in our study, covering a wide range of ages, our results are in essential agreement with published results on excised lenses. For a small subset of lenses in the study the assumption of a single fluorophor is found to be unsatisfactory. In these cases a reasonable symmetry assumption allows us to estimate the distribution of an additional agent which removes light from the entering or exiting beams without contributing to the fluorescence. The fact that this agent is restricted to the lens nucleus and that it occurs in lenses in which nuclear changes are clinically evident suggests that it is an expression of nuclear cataract.
A general numerical method evaluating three‐dimensional eye rotations by scanning laser ophthalmoscopy
Authors: Ott Dietmar , Lades Martin , Holthoff Knut , Eckmiller Rolf 
Published: December 2007

A general computational method is described to specify completely the rotational state of the eye in three dimensions by scanning laser ophthalmoscopy (SLO). The method uses the simplex algorithm to fit the eye's rotational parameters to data given by n individually selected ocular fundus landmarks before and after the eye rotation.The rotational parameters are expressed as the rotation vector and three spherical Euler angles. The method, which was implemented in the C programming language, can be applied for various eye movement measurements in clinical and laboratory environments, including SLO.
Eye drop container delivery: a source of response variation?
Authors: German Emma J. , Hurst Mark A. , Wood Diana 
Published: December 2007

SummaryVariations in response to topically applied ocular drugs (e.g. mydriatics and cycloplegics) and their possible aetiology have been studied previously. It appears that individual patient differences, external influencing factors and the characteristics of the particular drug may all govern the response. One factor worthy of note in this regard is the possibility of variation in the drug volume instilled. Single‐use eye drop containers known as Minims® are commonly used during ophthalmic diagnostic procedures. However, in this study the drop volume was shown to vary considerably, depending upon the angle at which the Minims® container was held, the particular drug and the number of drops previously expelled from the unit.
Use of contact lenses by firefighters: Part 2. Clinical evaluation
Authors: Owen Christopher G. , Margrain Thomas H. , Woodward E. Geoffrey 
Published: December 2007

SummaryContact lenses can be worn in a variety of environmental conditions and do not increase the wearers risk of injury. In many situations they offer significant corneal protection. Currently firefighters are prohibited from using contact lenses. To evaluate whether contact lenses are a safe form of visual correction 50 firefighters were fitted, and examined after 1, 4 and 10 months of contact lens wear. Twenty‐nine were fitted with soft contact lenses, and 21 with rigid gas permeable contact lenses. Statistically significant increase in lid sulcus hyperaemia was found in both the SCL and RGPCL groups (P<0.01, P=0.02. respectively), as well as an increase in hyperaemia of the vertical quadrant of the bulbar conjunctivae (P= 0.01, P= 0.02. respectively) In addition the RGPCL group showed a statistically significant increase in hyperaemia of the lateral portion of the bulbar conjunctivae (P<0.01), consistent with exposure epitheliopathy. The SCL group showed statistically significant increase in corneal staining in the vertical quadrant for all visits (P=0.02, P=0.01, P=0.02 for all visits, respectively), indicative of lens dehydration. These findings although clinically significant are not unique to firefighting, and are found within a “normal” population of contact lens wearers. In conjunction with questionnaire data (Owen et al., 1996) we conclude that soft contact lenses can be worn safely by firefighters without additional risk.
Vision and driving ‐ a literature review and commentary
Authors: Charman W. N. 
Published: December 2007

SummaryThe visual requirements that currently have to be met by those applying for and holding current UK driving licenses for private motor vehicles are discussed, together with the incidence of road accidents and the general scientific and social problems of setting visual standards for driving. Literature relating to the effectiveness of various visual tests in predicting the accident‐prone‐ness of individual drivers is reviewed. A striking feature of the data on the age‐dependence of accidents and visual performance is that although visual performance by most tests steadily declines after early middle age, older drivers have less accidents than their younger counterparts, whose visual performance is superior. It is concluded that, although correlations between poor vision as assessed by some tests and accident rates can be shown in large samples of drivers, as yet, no single test or combination of tests has been shown to be able to effectively screen out those at risk of accidents without also leading to the disqualification of a substantial number of potentially safe drivers. Thus no change in the present visual requirements is recommended at the present time.
Graphical representation of visual acuity data
Authors: Moseley Merrick J. 
Published: December 2007

SummaryAccurate graphical depiction of data requires that distances between points map precisely to the quantitative differences they represent. In the case of Snellen visual acuity, consecutive line sizes do not generally correspond to equal increments in visual angle, hence scores plotted against axes marked off in equal intervals provide a false representation of the relation between plotted values. A worked example illustrates the nature of this problem and its solution.
Sheep refraction, correction and vision in Lewis Carroll's Through the looking glass and what Alice found there (1871)
Authors: Piggins David , Phillips Clive 
Published: December 2007

SummaryThe reports and depiction of the vision and refraction of sheep by Lewis Carroll in Through the looking glass and what Alice found there (1871) appear to be at the very least optically ambiguous to the light of our contemporary knowledge of the refraction of the sheep eye with its large pupil and lack of accommodation and pupil closure.
Interconverting the matrix and principal‐meridional representations of dioptric power and reduced vergence
Authors: Harris W. F. 
Published: December 2007

SummaryConverting the traditional representation of power as sphere, cylinder and axis to the dioptric power matrix F is usually performed by means of Long's equations and the reverse process by means of Keating's equations. It is sometimes useful to be able to convert directly between the matrix and power expressed in terms of principal powers F| and F2 along corresponding principal meridians at angles a and a2. The equations for interconverting F and the principal‐meridional representation expressed as F^{a}F2 are presented here. Equivalent equations allow direct interconversion of the reduced vergence matrix L and the principal‐meridional representation of vergence L{a)L2. Vergence becomes infinite at line and point focuses. Similarly effective power and back‐ and front‐vertex power are infinite for some systems. Nevertheless it is possible unambiguously to represent infinite vergence and vertex power in principal‐meridional form. However, information is usually lost in these infinite cases when the principal‐meridional representation is converted to the matrix representation, and the former is not recoverable from the latter. As a consequence the matrix representation is usually unsatisfactory for vergences and vertex powers that are infinite. On the other hand, the principal‐meridional representation of vergence and power is always satisfactory. If one adopts the position that effective powers and vertex powers are really vergences rather than powers then one concludes that the matrix provides a satisfactory representation for powers of thin systems in general but not for vergences. Implied by a vergence at a point is an interval of Sturm. The equations for characterizing the interval from the reduced vergence are presented.
SOURCE ROCKS AND THE ORIGIN OF NATURAL GAS IN THE FAR EAST
Authors: Grunau Hans R. , Gruner Ueli 
Published: December 2007

Most source rocks of the Far East (Figs. 2 and 6) have a strong humic component, and, therefore, a large gas‐generating capacity. This is an obvious reason why the Far East as an entity is largely a gas province. In particular, the following statements can be made: (i) Mixed or humic type source rocks in combination with temperature gradients exceeding 3.5°C and minimal burial depths of 3,000m generate predominantly gas (e. g. Gippsland basin, SE Australia; Kapuni gas field, New Zealand). (ii) Mixed or humic type source rocks in combination with average or slightly below average temperature gradients and burial depths exceeding 3,200‐4,000m generate predominantly gas and condensate (e. g. Dampier sub‐basin, Western Australia; Arun gas field, North Sumatra). (iii) Mixed and/or humic type source rocks generate gas in the vicinity of magmatic intrusive or extrusive bodies provided magmatic activity post‐dates source rock deposition. (iv) Most source rocks of the Far East are Paleocene to Miocene age, and source rock maturity and post‐maturity was in many cases reached in Neogene to Recent times. (v) Mesozoic source rocks of partly humic or mixed type are known from Afghanistan and Australia, Paleozoic source rocks from Australia. (vi) Retention of the gas phase may have been inadequate in areas of strong Neogene folding (e. g. Sumatra, East Kalimantan and Burma Tertiary basins). (vii) At the present state of knowledge the question as to which part of natural gas is thermally degraded oil and which part stems from a gas source rock, cannot be satisfactorily solved.
EARLY DIAGENESIS AND THE PRESERVATION OF POROSITY IN JURASSIC LIMESTONES
Authors: Purser Bruce H. 
Published: December 2007

The study of Quaternary sediments has shown that carbonates are susceptible to early lithification, or to dissolution, in many different environments. Most of these surface effects, although reducing primary porosity, rarely destroy it completely. Although similar diagenetic phenomena also occur in ancient rocks, the great majority of limestones do not exhibit early diagenetic fabrics; much sparitic cement is possibly related to carbonate liberated by pressure‐solution within the limestone mass. In spite of the fact that carbonate sediments frequently have high initial porosities, most of it is destroyed by sparitic cement. The exceptional circumstances favouring the preservation of effective porosity may be related to the presence of an early diagenetic phase. A number of reservoirs exhibit early diagenetic cements, dissolution and dedolomitisation fabrics. It is concluded that early lithification tends to retard or prevent subsequent pressure‐compaction and thus reduces the volume of carbonate available for porosity destruction. The recognition of early diagenetic phenomena in ancient limestones therefore has important economic implications.
DIAGENETICALLY FORMED INTERSTITIAL CLAY MINERALS AS A FACTOR IN ROTLIEGEND SANDSTONE RESERVOIR QUALITY IN THE DUTCH SECTOR OF THE NORTH SEA
Authors: Seemann U. 
Published: December 2007

In Permian Rotliegend aeolian sandstones in the Dutch sector of the North Sea, kaolinite dominates over poorly crystallised, pore‐lining illite in areas of shallow burial. Fibrous, bridging illite dominates over kaolinite in the areas of deeper burial.This distribution of diagenetically formed interstitial clay minerals coincides with a regional permeability trend. Higher permeabilities occur in the area where kaolinite dominates over poorly crystallised, pore‐lining illite; lower permeabilities occur in the area where fibrous, bridging illite dominates over kaolinite.
COMPARATIVE PETROLEUM GEOLOGY OF SOUTHEAST TURKEY AND NORTHEAST SYRIA
Authors: Ala M. A. , Moss B. J. 
Published: December 2007

In terms of their regional tectonic setting, SE Turkey and NE Syria belong to the Persian Gulf basin, and the essential structural features of SW Iran and N Iraq are readily discernible here. Large, elongated folds of Alpine (Mio‐Pliocene) age dominate the structure of the region, and the intensity of deformation increases towards the north, in the direction of the Taurus orogenic zone.Five major depositional cycles have been recognized in the sedimentary record of SE Turkey and NE Syria, and the stratigraphy of the area has been outlined. The depositional cycles are late Precambrian, Cambro‐Devonian, Permo‐Carboniferous to Upper Jurassic, Lower‐Cretaceous to Lower Eocene and Middle Eocene to Recent in age. Important regional unconformities are present at the base of the Permo‐Carboniferous to Upper Jurassic and Lower Cretaceous to Lower Eocene cycles. The effects of the latter unconformity are particularly marked north of the Diyarbakir‐Mardin swell in southeast Turkey, and it has adversely affected the petroleum potential of this region.Several giant oilfields have been discovered in NE Syria, while in SE Turkey the accumulations are small by Middle East standards and are often only marginally commercial. The difference in size of accumulations is due to more favourable source, reservoir and caprock relationships in the former area. Many of the structures in NE Syria can be regarded as multi‐objective with Tertiary, Upper Cretaceous, Lower Jurassic and Triassic prospects, whereas in SE Turkey the effects of the late Jurassic–early Cretaceous uplift and erosion seem to have restricted the potential pay zones largely to the Upper Cretaceous–Palaeocene section.Geochemical evidence suggests separate sources for the Tertiary, Cretaceous and Lower Mesozoic crudes of NE Syria, and in SE Turkey much of the currently produced oil is believed to have been generated by late Maestrichtian–Palaeocene basinal shales. However, in both areas there is some evidence that at least part of the oils now trapped in Upper Cretaceous‐Tertiary reservoirs in certain fields may be of deeper origin.
ORGANIC MATTER AS INDICATOR OF THE DEGREE OF METAMORPHISM OF THE CARBONIFEROUS ROCKS IN THE SOUTH WALES COALFIELDS
Authors: Gill W. D. , Khalaf F. I. , Massoud M. S. 
Published: December 2007

Isoreflectance maps of vitrinites in coals and phytoclasts (coaly inclusions) in the Coal Measures of S. Wales show a progressive increase in vitrinite reflectance with increase in coal rank and grade of metamorphism towards the anthracite area in the west, without significant variation in reflectances of coals with present depth. Differences between values of vitrinite reflectance in coals and phytoclasts in the same profile are recorded and attributed to variations in depositional environments, and to susceptibility to alteration of the host rocks. Spores in the Coal Measures are progressively carbonized (from golden brown to black) towards the west, and this is not a function of present depth of burial. Reflectance of vitrinites in coals, degree of spore carbonization and coal rank are used in definition of three different diagenetic zones in the coalfield. The Coal Measures could have acted as a source for accumulations of gas in the Permo‐Triassic sequence of the south Irish Sea, if necessary geologic conditions are present. Burial metamorphism (application of Hilt's law) could have caused the coalification of S. Wales coals up to the high and medium volatile bituminous stages (up to the late diagenetic stage). A relationship is established between the lateral variation in coal rank in the coalfield and the regional variation in coal rank in the southern British Isles, where two regions of markedly different geothermal history are recognised. The Diagenetic Zone in the E and S parts of the coalfields marks the final stage in the thermal history of the cold region (the W margin of London Stable Massif), whilst the Anchimetamorphic Zone in the NW part (the anthracite area) represents the final stage in the thermal history of the hot region (the S margin of St. George's Land).Phytoclasts and spores are recorded for the first time from the Dinantian massive limestones of S. Wales.
THE PROVENANCE AND DISTRIBUTION OF THE PALAEOCENE SANDS OF THE CENTRAL NORTH SEA
Authors: Morton Andrew C. 
Published: December 2007

A study of the detrital heavy minerals from Palaeocene sandstones of the central North Sea basins has revealed that variations exist which cannot be explained in terms of varying conditions either during or after deposition, and therefore reflect the influence of distinct source areas. Four sand bodies have been defined on a mineralogical basis, two of which occur in the Central Graben and southern Viking Graben, derived from the E. Shetland Platform, the other two being developed in the Moray Firth area, derived from the Scottish landmass. These sand bodies, when related to the existing lithostratigraphic framework, define four phases of basin subsidence, with the sand depocentre alternating between the Central Graben and the Moray Firth basin. This oscillation in basin subsidence, the association with volcanogenic sediments and the apparent basement control on distribution of sands in the Moray Firth indicate a degree of tectonic control hitherto undescribed for the Palaeocene of the area.Studies of sandstones in or around the inferred source areas have revealed that the metamorphic basement was the major contributor to the sands of the Moray Firth, rather than the pre‐existing sandstones of Devonian, Permo‐Trias or Jurassic ages which occur on the margins of the Firth. Likewise the Old Red Sandstone or Permo‐Trias sandstones of the East Shetland Platform are not suitable source rocks for the sands of the Central Graben and in this case it has been necessary to postulate the existence, at least until the end of Palaeocene times, of Carboniferous sands on the Platform. Such sands in the central North Sea have been shown to possess a mineralogy not dissimilar from that of the Palaeocene sands in question.