bluuebunny/crossref_metadata_2025 huggingface dataset:
Aspirin‐induced asthma and HLA‐DRB1 and HLA‐DPB1 genotypes
Authors: DEKKER J. W. , NIZANKOWSKA E. , SCHMITZ‐SCHUMANN M. , PILE K. , BOCHENEK G. , DYCZEK A. , COOKSON W. O. C. M. , SZEZEKLIK A.
Published: April 2006

Background Aspirin‐induced asthma (AIA) affects one in 10 individuals with adult‐onset asthma. It is not known if aspirin sensitivity is due to immune mechanisms or to interference with biochemical pathways.

Objective The study aimed to test for possible involvement of the genes of the Major Histocompatibility Complex (MHC) in AIA.

Methods HLA‐DPB1 and HLA‐DRB1 genotyping was carried out by DNA methods in 59 patients with positive challenge tests for AIA and in 48 normal and 57 asthmatic controls

Results The DPB 1*0301 frequency was increased in AIA patients when compared with normal controls (19.5% vs 5.2%, Odds Ratio = 4.4, 95% Confidence Interval (CI) 1.6–12.1, P= 0.002), and compared with asthmatic controls (4.4%, OR = 5.3, 95%CI= 1.9–14.4, P= 0.0001). The frequency of DPB 1*0401 in AIA subjects was decreased when compared with normal controls (28.8% vs 49.0%, OR = 0.42, 95%CI = 0.24–0.74, P= 0.003) and asthmatic controls (45.6%, OR = 0.48, 95%CI = 0.28–0.83, P= 0.008). The results remained significant when corrected for multiple comparisons. There were no significant HLA‐DRB 1 associations with AIA.

Conclusion The presence of an HLA association suggests that immune recognition of an unknown antigen may be part of the aetiology of AIA.
Correlation between IgA antibody and eosinophil cationic protein levels in induced sputum from asthmatic patients
Authors: NAHM D.‐H. , PARK H.‐S.
Published: April 2006

Background Eosinophils are known to be main effector cells in allergic inflammation and IgA antibody has been shown to be a potent stimulus for eosinophil degranulation in in vitro conditions.

Objective To evaluate the possible role of IgA antibodies on eosinophil degranulation in lower respiratory mucosa of asthmatics, we tried to find a correlation between total IgA and eosinophil cationic protein (ECP) levels in induced sputum from asthmatics.

Methods We measured total IgA and albumin levels by nephelometry, and eosinophil cationic protein levels by Pharmacia CAP system in induced sputum from 23 atopic asthmatics and 12 healthy controls.

Results IgA and albumin levels in induced sputum from asthmatics with sputum eosinophilia (sputum eosinophil count 5% of 200 counted non‐squamous cells) were significantly higher (P < 0.05) than those from controls. However, IgA and albumin levels in induced sputum from asthmatics without sputum eosinophilia were not significantly different with those from controls (P > 0.05). In induced sputum from asthmatics, ECP levels were significantly correlated with albumin (r= 0.44, P= 0.04) and IgA levels (r= 0.67, P= 0.002). ECP/albumin ratio was also significantly correlated with IgA/albumin ratio (r= 0.61, P= 0.004).

Conclusion Our results support the hypothesis that IgA antibodies in tracheobronchial secretion may be involved in eosinophil degranulation in asthma, and further study is needed to prove this hypothesis.
Prevalence and distribution of indoor allergens in Singapore
Authors: ZHANG L. , CHEW F. T. , SOH S. Y. , YI F. C. , LAW S. Y. , GOH D. Y. T. , LEE B. W.
Published: April 2006

Background and aims
Immediate hypersensitivity to indoor allergens is known to be associated with allergic asthma. This study evaluated the prevalence and distribution of six indoor allergens in 956 dust samples obtained from homes, childcare centres, schools, and a hospital in tropical Singapore. Seasonality of mite allergens was also assessed.

Methods
The major allergens of the Dermatophagoides spp. dust mites, Der p l and Der f 1; major cat and dog allergens, Can f 1 (dog) and Fel d 1 (cat); and cockroach, Bla g 1. were measured by specific enzyme immunoassays. Allergen levels of the storage mite. Blomia tropicalis (Blot), were measured by a fluorescent allergosorbent test (FAST) inhibition assay.

Results
Our results showed that homes had significantly higher concentrations and prevalence of allergens compared with the other locations, except for Bla g 1, where higher mean levels were found in schools. Within the homes, the highest concentrations of mite allergens were found in mattresses (geometric mean: 1.2 μg/g dust Der p 1; 2717 Allergen Units per gram dust [AU/g] Blot), and carpets (1.5 μg/g Der p 1; 1620 AU/g Blo t), whilst Bla g 1 was mainly concentrated in the storerooms (geometric mean = 3.5 units/g) and kitchens (geometric mean = 5.1 units/g). The major cat and dog allergens were well distributed and not confined to homes with pets. Their highest levels were found in dust of soft furnishings, carpets and mattresses. There was an absence of significant seasonal variation in Der p 1, Der f 1 and Blo t levels in the homes over a 1 year period.

Conclusion
The results indicate that compared with public places, the home consitutes a major reservior of indoor allergens. Allergens of the storage mite, B. tropicalis, should be considered as a major allergenic component of dust in Singapore.
Monoclonal and polyclonal antibodies against casein components of cow milk for evaluation of residual antigenic activity in ‘hypoallergenic’ infant formulas
Authors: PLEBANI A. , RESTANI P. , NASELLI A. , GALLI C. L. , MEINI A. , CAVAGNI G. , UGAZIO A. G. , POIESI C.
Published: April 2006

Background
Hydrolysed casein and whey protein formulas have been developed with the aim of preventing sensitization in infants at high risk of cow milk allergy. Subsequently these products have also been used tor treatment of children with cow milk allergy. However, severe reactions have occurred in some allergic infants led with these formulas raising doubts about their absolute safety and suggest the need for developing in vitro techniques for detection of eventual residual allergenic activity in such preparations.

Objectives
Our purpose was to evaluate the usefulness of monoclonal and polyclonal antibodies against casein components (αβ and κ casein) as reagents for the detection of the residual antigenic activity of casein components in several hydrolysed formulas.

Methods
The monoclonal and polyclonal antibodies were produced according to standard procedures by immunizing female Balb/c mice with casein fraction (a mixture of α, β and κ casein). ELISA assays were developed to test the specificity of the antibodies and to detect and evaluate the amount of residual antigenic activity of the casein components in hydrolysed formulas.

Results
Use of polyclonal antiserum specific for casein allowed detection of residual antigenic activity of casein components in all partial hydrolysates and in the two extensive whey protein hydrolysates in the amounts ranging from 0.05 to 0.67% of total protein. No such activity was detectable in either the two extensive casein hydrolysates tested or the aminoacid based formula. The polyclonal antiserum proved to be more suitable than monoclonals for detecting residual antigenic activity in the hydrolysates. The monoclonal antibodies were directed against epitopes expressed on different casein components.

Conclusions
In this study the ELISA inhibition assay with polyclonal antibodies specific for casein components of cow milk proved to be a sensitive method for estimating residual antigenicity in the hydrolysed formulas commercially available for infants with cow milk allergy suggesting their potential application for the quality control of hypoallergenic infant formulas.
Determination of independent risk factors and comparative analysis of diagnostic methods for immediate type latex allergy in spina bifida patients
Authors: DE SWERT L. F. A. , VAN LAER K. M. I. A. , VERPOORTEN C. M. A. , VAN HOEYVELD E. M. , CADOT P. , STEVENS E. A. M.
Published: April 2006

Background
Development of allergy to natural rubber latex in spina bifida patients is determined by several risk factors, such as age, number of interventions and atopic disease that are, however, interdependent. Furthermore, several diagnostic procedures have been analysed, but a comprehensive analysis of their diagnostic significance is lacking.

Objective
To determine the independent major risk factor(s) for development of natural rubber latex allergy and the most valuable diagnostic procedure.

Methods
In aselectively collected spina bifida patients, we correlated existing natural rubber latex allergy with age, sex, atopy and the number of hospitalizations and of surgical interventions in appropriately matched subgroups. Allergy to natural rubber latex was established by application of a latex glove fragment on the skin. Skin‐prick tests with glove eluate, a natural latex extract and a commercial latex extract were carried out as were specific IgE measurements by radioimmuno assay (RAST‐CAP). The results of the latex application test are compared with the other diagnostic methods.

Results
Out of 74 fully evaluated patients, 17 had a positive application test. The number of surgical interventions correlates strongly with the presence of natural rubber latex allergy (P < 0.0002), independent of age, sex and presence of atopy. Skin‐prick tests with unstandardized allergens made from known high allergenic latex gloves represent the most sensitive diagnostic method, with the highest negative predictive value and a specificity of 0.95. RAST‐CAP was the next best method with a specificity of 0.93, a sensitivity of 0.89 and a negative predictive value of 0.97.

Conclusion
The number of surgical interventions is the major independent determining factor for allergy to natural rubber latex in spina bifida patients. Unstandardized skin‐prick tests are the most sensitive and specific diagnostic tool, but RAST‐CAP is almost equally performant and therefore a valid alternative.
Effects of levocetirizine as add‐on therapy to fluticasone in seasonal allergic rhinitis
Authors: Barnes M. L. , Ward J. H. , Fardon T. C. , Lipworth B. J.
Published: April 2006

Background
Addition of H1 antagonists to intranasal corticosteroid treatment of allergic rhinitis (AR) is common in clinical practice and recommended by guidelines, despite some evidence that the additive benefits are negligible.

Objective
To assess additional benefits of 5 mg levocetirizine dihydrochloride in seasonal AR patients using 200 mcg fluticasone propionate nasal spray once daily.

Methods
In a double‐blind placebo‐controlled crossover study of 27 patients, following 2 weeks without treatment, subjects used fluticasone with levocetirizine or identical placebo for 2 weeks each. Assessments were the Juniper mini Rhinoconjunctivitis Quality‐of‐Life Questionnaire (mini‐RQLQ), domiciliary peak nasal inspiratory flow (PNIF), total nasal symptoms (TNS) scores and nasal nitric oxide concentrations. Effects were interpreted and tested against minimal clinically important differences.

Results
Add‐on effects for levocetirizine vs. placebo excluded any clinically significant benefits: mean effects (one sided 95% confidence intervals) were mini‐RQLQ −0.11 (−0.34), PNIF +0.57 (+5.23), and TNS −0.11 (−0.60). Numbers needed to treat (95% confidence intervals) by outcome were mini‐RQLQ 14 (5 to 49), PNIF 4 (3–7), and TNS 3 (2–6). No significant within or between treatment effects were seen for nasal nitric oxide.

Conclusion
Contrary to current practice, the present results demonstrate that for the majority of patients, antihistamine add‐on to effective nasal steroid treatment is inappropriate. Further work is required to confirm that this is also true in the most severe cases, and the available evidence needs to be put into guidelines and implemented.
Is the effect of probiotics on atopic dermatitis confined to food sensitized children?
Authors: Sistek D. , Kelly R. , Wickens K. , Stanley T. , Fitzharris P. , Crane J.
Published: April 2006

Background
Probiotics have previously been shown to reduce the severity of atopic dermatitis (AD) in infants and children.

Objective
To examine the effect of two probiotics (Lactobacillus rhamnosus and Bifidobacteria lactis) on established AD in children.

Subjects and methods
Atopic children with current dermatitis received 2 × 1010 colony forming units/g of probiotic (n=29) or placebo (n=30). Both were given daily as a powder mixed with food or water. SCORing Atopic Dermatitis (SCORAD; developed by the European Task Force on Atopic Dermatitis) a measure of the extent and severity of AD, was assessed at baseline, 2 and 12 weeks after starting treatment and 4 weeks after treatment was discontinued.

Results
SCORAD geometric mean score at baseline was 26.0 (21.9–30.8) in the probiotic group and 35.1 (28.9–42.8) in the placebo group (P=0.02). After adjustment for these between‐group baseline differences there was no significant improvement in AD at 12 weeks, SCORAD geometric mean ratio: 0.80 (95% confidence level (CI) 0.62–1.04, P=0.10). Among the food sensitized children, there was an improvement in those treated with probiotics, SCORAD geometric mean ratio: 0.73 (95% CI 0.54–1.00, P=0.047).

Conclusion
In this study a combination of Lactobacillus rhamnosus and Bifidobacteria lactis improved AD only in food sensitized children.
Smoking and occupational asthma
Authors: Siracusa A. , Marabini A. , Folletti I. , Moscato G.
Published: April 2006

Cigarette smoking is a known risk factor for many chronic illnesses such as coronary heart and chronic obstructive pulmonary diseases. Smoking is often described as a risk factor for occupational asthma even though its effect on the development of asthma is still under debate and the links between smoking and occupational asthma, occupational rhinitis or occupational sensitization are elusive, controversial and contradictory. This review describes these relationships in a wide range of occupations, from laboratory, farm, brewery and hospital workers, to bakers, printers, cleaners, fish processors and others as observed in cross‐sectional, cohort, and case‐control studies published over the past thirty‐five years i.e. from 1970 to 2005. Surprisingly, the data show there is little to support the view that the risk of occupational asthma is increased in workers who are smokers. However, evidence emerges of an increased risk of occupational sensitization in smoking workers exposed to several high and low molecular weight agents. This in‐depth review confirms the relationship between smoking and occupational asthma is complex and contradictory. It deserves more attention and further studies, which need to be conducted without being influenced by selection bias or by the justifiable prejudice against smoking.
Treatment of erythrasma with miconazole
Authors: PITCHER D.G. , NOBLE W.C. , SEVILLE R.H.
Published: April 2006

Miconazole cream was compared with Whitfield's Ointment in a single blind trial for the treatment of erythrasma amongst patients in a hospital for the mentally subnormal. There was no significant difference in the effectiveness of the preparations when applied twice daily; more than 90% of all sites were cleared, although miconazole cream was much less irritating than Whitfield's Ointment.
Photochemotherapy for psoriasis remission times. Psoralens and UV-A and combined photochemotherapy with anthralin
Authors: CRIPPS D.J. , LOWE N.J.
Published: April 2006

Oral methoxsalen and long-wave ultraviolet light (PUVA) was evaluated in 187 psoriatics, with emphasis on remission and recurrence after therapy. The mean number of years psoriasis had been present was 18.3, the mean psoriatic involvement 34.8% the dose at the time of maximum clearance was 11.8 J/cm2, and the mean number of treatments to achieve maximum clearance was 175. Complete clearance was achieved in sixty-one patients and in this group the average number of treatments to achieve maximum clearance was 16.8, the initial remission times ranged from 4 to 64 weeks, with an average of 21.6 weeks. In patients subsequently retreated, the remission time was only 12.4 weeks (57%), but the mean number of treatments to achieve maximum clearance was reduced (11.4) and patients responded more easily to treatment. Sixteen patients were treated in addition to PUVA, with anthralin in Lassars' paste with clearing achieved between six and fifteen treatments, a mean of 9.5.

Combinations of PUVA with other forms of psoriatic treatment may also help to reduce the cumulative PUVA exposures.
UNE REGLE POUR LES CALCULS DE SISMIQUE‐REFRACTION*
Authors: GOGUEL JEAN
Published: April 2006

Abstract

A ruler has been constructed to solve seismic refraction problems with horizontal or slightly inclined layers.
GRAVITY EFFECT OF EARTH TIDES*
Authors: BAARS B.
Published: April 2006

Abstract

The gravity effect of earth tides was measured simultaneously at 26 stations, with 2 instruments at 3 of the stations. After a description of the stations, the corrections on the measurements are described. The results for the separate measurements are given and it can be stated that, within the accuracy of the measurements is very probably constant and has a value of 1.22. If this value is combined with Nishimura's value 0.66 for (1 − h + k), it can be shown that Takeuchi's earth models fit these values provided a value of 2.7 is taken for the surface density of the earth. The importance of a constant value for in gravity surveys is pointed out.
APPLICATION OF VERTICAL GRADIENTS AND COMPARISON OF DIFFERENT GEOPHYSICAL METHODS IN A DIFFICULT AREA*
Authors: SELEM A. M. , MONNET C.
Published: April 2006

Abstract

Seismic reflection, telluric and gravity results are given for the lifted area of Ferrara, in Northern Italy. The agreement is shown between the available shallow seismic data and the gravity evidences. For a portion of the above area where seismic results are particularly poor the vertical gradients method gives a resolution of a gravity anomaly and confirms the telluric information. The residual gravity values, the vertical gradients and the telluric data along a seismic line crossing the zone are compared with seismic results and with evidences from adjacent wells.
SOME PRACTICAL EXAMPLES OF INTERPRETATION OF TELLURIC METHODS IN LANGUEDOC (SOUTH‐EASTERN FRANCE)*
Authors: MAINGUY M. , GREPIN A.
Published: April 2006

Abstract

In the region covered by the paper, electrical methods have been applied in four different zones:

Ales‐Maruejols Basin (resistive lower Oligocene blanketed by conductive Upper Oligocene);

Ledignan and Vaunage‐Lunel anticlines (faulted structures in the marly and limy Cretaceous, with different resistivities;

Camargue (thick series of conductive sediments);

Beziers Basin (highly complicated structures in the Mesozoic, widely blanketed by conductive Miocene).

It may be assumed that electrical methods can yield valuable information enabling one to define the rugged subsurface topography of resistive strata burried under a reasonably thick cover of conductive sediments especially when a part of the lower formation outcrops even if the part exposed be small. Faults may be delineated and much, more information is obtainable than can be expected from gravity meter survey at a price not very much higher.
A COMPARISON OF THE SECOND DERIVATIVE METHOD OF GRAVITY INTERPRETATION WITH REFLECTION SEISMICS AND GEOLOGICAL FINDINGS IN THE OFFENBURG AREA*
Authors: ROSENBACH OTTO , KOEHLER R. , WIRTH E.
Published: April 2006

Abstract

The aim of the present investigation is to examine the significance of the second derivative for the purpose of the prospective determination of the geological properties of the district of Offenburg, which are relatively wellknown as a result of both reflection seismic and bore profile findings.

The calculation of the second derivative is carried out by means of three approximation formulae, which are compared with each other. In contrast to the isogam map the second derivative shows some additional characteristics, whose structural significance illuminates the comparison with the results of reflection seismics.

A geological profile constructed on the basis of 6 wells completely confirms the geophysical findings.
EXTENSION TO THREEDIMENSIONAL PROBLEMS CONCERNING AN APPROXIMATE CORRECTION METHOD FOR REFRACTION IN REFLECTION SEISMIC PROSPECTING*
Authors: KREY TH.
Published: April 2006

Abstract

The formulas derived by the author in a preliminary paper for taking into consideration refraction when dealing with the problem of a vertical plane are extended to the three‐dimensional case. Vector analysis is extensively applied. Among others it is shown that in the general case the 3 horizontal twodimensional vectors, i.e.

the gradient of the time of reflection

the direction of true dip

the vector from the shot point to the projection of the reflecting point, point into 3 different directions.
DIE ABHÄNGIGKEIT DES SCHEINBAREN WIDERSTANDES VOM SONDENABSTAND BEI DER VIERPUNKT‐METHODE*
Authors: DEPPERMANN K.
Published: April 2006

Abstract

The dependence of the apparent resistivity on the distance between the potential electrodes is examined and a numerical method is described permitting quantitative calculations. Such a numerical relation is also established for the transformation of Wenner graphs into Schlumberger graphs.

In addition it is shown, in which manner the jumps in observed Schlumberger curves, that result from changing the probe spacing, must be smoothed out.
SOME OBSERVATIONS ON SEISMIC WEATHERING CORRECTIONS
Authors: KOEFOED O.
Published: April 2006

Abstract

When a rather extensive network of short distance refraction profiles was shot the following two observations were made. Firstly, the wave velocity in the weathered layer showed a quite considerable fluctuation in horizontal direction, the extreme values being of the order of 300 and 700 m/sec. A practical result of this scattering of the velocities is that an uncertainty of about 10% is introduced in the computation of the weathering corrections. The second observation is that, in the majority of cases, the travel time curve does not pass through the origin. It could be ascertained that this observation was not caused by errors in the method of observation. A probable explanation of the phenomenon is found in a theory that has been developed by Gassmann, who derived the velocity distribution for a hexagonal packing of spherical solid bodies. According to this theory extremely low velocities would occur in the first few centimeters of the crust of the earth. Qualitatively, our observations are in agreement with the theory of Gassmann.
A REMARK CONCERNING THE PROBLEM OF HOW TO PLACE THE REFERENCE PLANE (DATUM LEVEL) IN REFLECTION SEISMIC PROSPECTING*
Authors: KREY T.
Published: April 2006

Abstract

It has been shown in a paper by L. Y. Faust that the wave velocity in rock depends on the depth below the ground surface according to a specified equation. It follows that the attitude of the planes of equal velocity is influenced by the topographic relief. Under these conditions the problem arises of how to place the reference plane in such a manner, that the fluctuations of the planes of equal velocity, that result from the fluctuations in the topography, shall not affect the results of the depth computations. In the present paper an analytical solution of this problem is given.
MESURE DU BRUIT ET SISMOS MULTIPLES (etude experimentale dans les Landes)*
Authors: RICHARD HENRI , RIMBAUT MARCEL
Published: April 2006

To improve the ratio of signal to noise resulting from the shot, seismologists have increased the number of geophones in each recording channel and have also increased the length of each spread. As a rule, however, the effectiveness of this multiple recording is based on theoretical considerations, and it appeared desirable to carry out an experimental investigation to obtain a direct measurement of the reduction in noise as a function of the geophone pattern etc. The work was done in the Landes where experience had shown that recording was difficult.

The experimental arrangement, which allowed the accurate measurement of the noise without interference from reflected energy, is described.

Shots, repeated under apparently identical conditions, revealed the random nature of the noise and pointed to the necessity of a large number of experiments to yield an accurate result. Two geophone patterns were employed, one of 12 geophones in a straight line and the other of two parallel lines of geophones, the directions of the geophone lines being either along the shot line, perpendicular to the shot line or at some intermediate angle.

The results obtained, in two widely spaced locations were in good agreement and allowed definite conclusions to be drawn. When the 12 geophone line is long enough the noise is reduced by a factor of 0.36 and with two lines, each 55 metres long and containing 12 geophones, the reduction was 0.29, if the lines were sufficiently widely separated. The results agree with the factor K N‐½ for the reduction in noise where N is the number of geophones per trace and K is a factor close to unity. The results also show the influence of the length of the geophone line its orientation and its mean distance from the shot.
RELATIVE DETERMINATION OF THE DENSITY OF SURFACE ROCKS AND THE MEAN DENSITY OF THE EARTH FROM VERTICAL GRAVITY MEASUREMENTS*
Authors: DOMZALSKI W.
Published: April 2006

Abstract

The gravity difference between two stations, one at the surface and the other underground vertically below the former and at a given distance from it, depends on the mean density of the earth, σm as well as on the density of the layer of rock contained between the two stations. When one of these densities is known, the other can be computed from this gravity difference. The reliability of this determination depends on the relative accuracies with which σm and σ can be obtained.

These accuracies are discussed in the paper. The mean density of. the earth has been determined with an accuracy of approximately 0.01 gr/cm3. The determination of the density of a layer of rock depends on density determinations of rock samples which are not representative of the layer as a whole. Thus the accuracy of the value of σ based on a number of sample determinations will depend on many factors, including the method of averaging the density values obtained from the samples and the degree of uniformity in the geology.

To investigate the problem discussed above, three sets of gravity measurements were made under differing conditions. In each instance a number of pairs of stations vertically above each other were occupied on the surface and underground. The results computed from the data on each pair of stations in a set of measurements were considered as repeated measurements of the same quantity, and the most probable value was calculated.

The results demonstrated that the accuracy varied with the conditions prevailing in the area where the observations were made. In Godstone Quarries the dip of the strata was negligible, the rocks fairly uniform and structural conditions undisturbed. Consequently, although the rock layer between the surface and underground stations was only of the order of a hundred feet, the mean density of the earth computed from the average density of the rock samples, was very close to the accepted standard value of 5.52 gr./cm3. This agreement, however, was easily upset when only one random sample density was assumed as representative of a given formation.

In a different locality in Cumberland the observations were made in a mine and on the surface. The rock layer between the surface and the underground stations was approximately a thousand feet thick. One set of measurements followed a line parallel to a fault, the other a line crossing this fault. The results differed appreciably from the standard value of σm, particularly in the latter case.

It is concluded that the gravity difference between a surface and an underground station can be used satisfactorily to determine the average density of a rock layer in situ and en bloc, using the standard value for the mean Earth density.
UN INTÉGRATEUR POUR LE CALCUL DES CORRECTIONS TOPOGRAPHIQUES*
Authors: BOLLO R. , GOGUEL J.
Published: April 2006

Abstract

When gravimetric prospecting is concerned with a region featuring broken relief the calculation of topographical corrections becomes vitally important, for these rectify apparent anomalies completely. It is essential that they should be calculated as exactly as possible. By the classic method this takes an extremely long time and may in the long run involve an outlay actually higher than that expended on operations on the terrain.

It has thus been felt necessary to seek methods which would speed up calculation, and, bearing that in mind, the use of a polar integrator has been envisaged. With this the contour lines of a map can be followed between two fixed radii, the pole corresponding to the location of the position. Two integrator roulettes will give the values of the first two terms of the expansion in terms of the quotient of the height divided by the distance, the second of the terms resulting from the curvature of the earth. Unless there are escarpments very close to the position, the use of these two terms will be sufficient.

Polar integration will deal successively with different contour lines and a subsidiary graph will be plotted, giving the value of each of the integrals in terms of the height. By means of this subsidiary graph the values of the corrections will be obtained with a planimeter and a moment integrator. It is envisaged that the same operation could be repeated in the case of two maps with different scales, for instance, 1–20,000 and 1–200,000 the effect of the areas in the immediate neighbourhood of the position being taken into account by the observer. It is hoped that in this way the calculation of topographical corrections will be made quicker, more exact and less laborious.
ETUDE THEORIQUE DE LA VITESSE DES ONDES DE COMPRESSION DANS LES VASES*
Authors: D'ERCEVILLE I.
Published: April 2006

Abstract

It has been noted that in water‐saturated silt, the velocity of propagation of longitudinal waves is very low. The purpose of this paper is to suggest a theoretical explanation for this phenomenon.

The medium under study is assumed to consist of identical solid spheres piled one upon the other in a regular array, with the fluid filling the interstices. First the velocity of propagation is calculated for the system of the solid particles alone; then, utilizing the results obtained for this case, the velocities for the solid‐fluid system are calculated. Two velocities are obtained, one of them being higher and the other lower than in the case where no fluid is present.
TEMPLATES FOR FITTING SMOOTH VELOCITY FUNCTIONS TO SEISMIC REFRACTION AND REFLECTION DATA*
Authors: HAGEDOORN J. G.
Published: April 2006

Velocity functions can be grouped into families, any One of which results, in seismic pictures differing among themselves only in their scales of time and distance but similar in all other respects. For any one of these families it follows that curves drawn on logarithmic scales of time and distance to represent a particular relationship between seismic quantities will be similar in shape. This leads to the use of templates with logarithmic scales for fitting a smooth velocity function to a set of seismic data. Suitable templates for fitting refraction and reflection data to velocity distributions linear with either depth or vertical time are presented. An insight into the uncertainties involved is obtained with the aid of numerical examples.
THREE DIMENSIONAL GRAVITY SURVEY*
Authors: DOMZALSKI W.
Published: April 2006

The paper describes and discusses the results of an experimental gravity survey which was carried out underground on different levels of a mine, in the mine shafts, and on the surface above the mine workings.

The paper is composed of three complementing sections. The part dealing with gravity measurements in the shafts gives also attention to the particular problem of the terrain corrections underground, due to the surface topography. The interval densities from gravity measurements in the shafts are computed and adjusted in accordance with known geology and compared with the stratigraphical columns of the shafts. The effect of the ore body on the stations in the shaft is derived theoretically and compared with the observed one.

The gravity contours are constructed on different levels in the mine workings and discussed in relation to the known extent of the ore body. The gravity profile across a fault underground is presented and discussed. Another gravity profile was run underground in the same plan position as a surface traverse 1000 feet above it. The line of boreholes along this traverse gives good account of geology which includes step‐faulting. This known geology is compared with the deductions based on the gravity results. This is also done in the case of another gravity profile run over a known geological section. A number of gravity measurements were also taken in the same plan position, separated by the vertical distance of 800–1,100 feet. These points were placed by the boreholes previously drilled in the area. Attempt in correlation of these and gravity results is made.

The densities computed from the gravity measurements are compared with the laboratory determinations of the densities, carried out on samples from different parts of the mine.

The contours on the top of the base formation are constructed from the information obtained from the boreholes, and are compared with the gravity contours on the surface above.

A simple method of computation of the effects of slabs and blocks is presented as applied to the calculation of the corrections for underground drifts and faults. A table is appended for use with this method.
THE RELATION BETWEEN SIZE OF CHARGE AND AMPLITUDE OF REFRACTED WAVE*
Authors: GASKELL T. F.
Published: April 2006

Abstract

Experiments carried out using charges of up to 200 lbs. at a distance of about 20,000 ft. from the geophones suggest that the amplitude of the refracted wave ground motion is roughly proportional to the weight of charge. Simple energy considerations lead one to expect a relation of a form in which velocity amplitude is proportional to W.

An explanation of the observed relation may be based on a theory according to which the efficiency of the explosion increases with the source size, that is the distance from the source at which the pressure wave of the explosion ceases to cause permanent deformation of the surrounding medium.

The above theory was further confirmed by measurements of the radius of the cavity produced by explosions of charges of different size in clay. Also, explosion of charges in artificial water‐filled cavities were found to give seismic wave amplitudes three or four times greater than those produced by the same charge in a narrow hole. It is possible that these observations explain in part why the charges required in marine refraction experiments are very much smaller than those needed in refraction work on land, but additional reasons for this difference are also discussed.
PURPOSE OF ACCIDENT REPORTS AND STATISTICS*
Authors: RICHARD H.
Published: April 2006

The President of the E.A.E.G. Safety Committee has stated that European geophysicists fail to attach sufficient importance to accident statistics. Nevertheless these statistics are the best means at our disposal for the study of the factors influencing the number and severity of accidents.

It appears essential that two points should be stressed, firstly that the accident reports must be completed correctly, and secondly that the interpretation of each report and of the statistical data must be done systematically.

If these conditions are fulfilled it should be possible to create, at all levels, a technical and psychological atmosphere which would do much to protect geophysicists against accidents.
EINIGE NEUERUNGEN AN DEN GEOMAGNETISCHEN FELDWAAGEN*
Authors: FANSELAU G.
Published: April 2006

At the Niemegk Observatory geomagnetic balances with torsion ribbons have been constructed since a few years. They have well known advantages over balances resting on knife edges: greater stability of the zero position, ease of enlarging the measuring range by torsion, no serious damage when the instrument is not clamped. Both H‐ and Z‐ balances have proved highly satisfactory. Also a combined H‐and Z‐balance has been developed. To a certain extent, the torsion ribbon balances can be made insensitive to levelling errors. Torsion wire balances used as zero instruments have not been considered for field measurements for reasons of time saving, They are however being made for laboratory measurements.
PRINZIPIELLE BEMERKUNGEN ZU THEORIE UND PRAXIS DER METHODE DER ZWEITEN ABLEITUNG BEI DER INTERPRETATION GRAVIMETRISCHER MESSERGEBNISSE
Authors: ROSENBACH OTTO
Published: April 2006

The first part of the paper deals with theoretical considerations concerning the arithmetic mean of gravity values and its use with regard to the derivation of approximation formulae for the second derivative. In order to calculate the second derivative in practice the arithmetic mean. ḡ(r) of a continuum of gravity values on a circle of radius r is approximated by a Taylor polynomial and then replaced by the arithmetic mean gn(r) of n discrete gravity values. Because of the invariance of ġ(r) with regard to rotations of the coordinate system in the horizontal datum plane there exists a lower limit for the number n; this lower limit depends on the degree of the Taylor polynomial used in the formula for gzz.

The general results of the first part yield routine formulae for the special case of a regular hexagonal grid; these formulae are given and discussed in the second part of the paper. Three formulae are applied to the gravity data of the Los Angeles Basin. Some remarks concerning the comparability of different approximation formulae and some hints with regard to routine calculations conclude the paper.
ON THE BEHAVIOUR OF A WORDEN GRAVIMETER FOR PERIODICAL VARIATIONS IN EXTERNAL TEMPERATURE AND RAPID VARIATIONS OF PRESSURE *)
Authors: CAPUTO MICHELE
Published: April 2006

1. A Worden gravity meter has been tested for sinusoidal variations in the external temperature, by determining simultaneously the corresponding variations of temperature inside the Dewar vacuum bottle, and the variations in the readings.

A second Worden gravimeter has been tested for rapid variations in external pressure.
THE VARIATION WITH DISTANCE OF THE AMPLITUDE OF CRITICALLY REFRACTED WAVES *)
Authors: O'BRIEN P. N. S.
Published: April 2006

Abstract

Amplitude measurements have been made of the height of the first peak of an arrival refracted from a shallow refractor. If the amplitude is assumed to decay as the inverse mth power of the distance, the least squares value for m is found to be 2.16 ± .04. Because of this value and because of the character of the recorded event it is concluded that the arrival is a simple critical refraction. After applying the theoretical ‘spread’ factor for critical refraction there remains a residual attenuation of 1.96 ± 0.28 decibels per 1000 feet. The predominant frequency in the pulse is about 20 c.p.s. and this attenuation agrees with the losses found for such a frequency by extrapolation of the published results of other workers. Although no evidence could be seen on the records for a change of pulse frequency with distance, the quoted result would be consistent with a dependence of residual attenuation on the first power of the frequency, and would be inconsistent with a dependence on the second power of the frequency.

It is concluded that studies of the amplitudes of refracted events will give useful estimates of the attenuation factors of rocks.
QUELQUES EXEMPLES DE DIFFRACTIONS EN SISMIQUE‐REFRACTION ET LEUR APPLICATION A LA DETERMINATION DES VITESSES VERTICALES*
Authors: LEDOUX Y.
Published: April 2006

The progress in the registration of refraction shots obtained in the last years permits a more systematic study of the secondary arrivals. In zones with disturbed tectonics, a noticeable portion of the received energy derives from diffraction phenomena caused by velocity anomalies in the marker bed or in the overburden (faults, local heterogeneities). Some characteristic examples are presented and schematically explained.

A more advanced analysis of the branches of the travel time curve caused by diffraction leads, in favourable cases, to a new method of calculating the offsets and the vertical velocities, independent of the usual methods for the determination of these parameters.
DENSITY DETERMINATION ON NEAR‐SURFACE LAYERS BY GAMMA ABSORPTION*)
Authors: HOMILIUS J. , LORCH S.
Published: April 2006

From gamma ray absorption the density of soil to a depth of i m. can be determined in situ, without taking samples, by a method which has been described in a previous paper (Wendt 1954) and which has been checked with satisfactory results (mean error about 1%). A nearly vertical steel rod with a gamma ray source at its lower end is pushed into the ground, and the gamma radiation is measured at the surface with two counters placed symmetrically with respect to the rod.

As a first step in interpreting the observed effects, the assumption had been made that counters are infinitesimally small. This paper shows how a theory can be developed without this assumption, the finite dimensions of the counters being taken into account by an integral expression. For this purpose a determination of the dependence of the counting rate on the angle of incidence of the gamma rays is required. A comparison of the experimental results with the theoretical ones demonstrates that the integral expression is correct.

The influence of deviations from the normal geometry of the arrangement (e.g. caused by bending of the probe) on the results is investigated, as well as the influence of variations of the density with depth.

The treatment of the basic problems has been carried through in such a manner that the results obtained can be applied to other absorption methods as well.
THEORETISCHE UNTERSUCHUNG ÜBER DIE MEHRFACHAUFSTELLUNG VON GEOPHONEN*
Authors: KÜPPER FRANZ JOSEF
Published: April 2006

The receiving of seismic waves by multiple geophones (geophone‐group) is described by a system of coupled differential equations considering only effective resistances. For so‐called symmetrical connections of the geophone‐group which are used in practice nearly in all cases, a method can be given for solving this system of differential equations. The solutions so derived are valid for seismic waves of any shape. The calculation takes into account the coupling of the geophones as well as the building‐up transient oscillations.

A suitable measure of superposition is defined, based on the energy transferred during the receiving of the seismic waves. By this means effects similar to interference are investigated which occur at the geophone‐group. As a numerical example calculation is carried out for a geophone‐group consisting of three geophones which is excited by impulse‐shaped waves of the form of a damped sinusoidal oscillation. The occurring effect of superposition and its dependence on direction are discussed. In the appendix formulae are presented for investigation of further numerical examples.
AN ACCURATE GRAPHICAL METHOD FOR INTERPRETING SEISMIC REFRACTION LINES*
Authors: HALES F. W.
Published: April 2006

A method of refraction computing is described which establishes the two points of incidence at the surface of the ray‐paths from any point on the refractor when observed from opposing directions. The distance between these points is used to determine the radius and the centre of a circle to which the refractor must be tangential. The matching of forward and reverse data is intrinsic in the method so that the resulting profile is automatically positioned in depth. It is shown that if the effects of dip are neglected, errors are introduced in the derived radius and also in the position of the centre but these errors are shown to cancel each other almost exactly.
THE CAUSES OF GEOPHYSICAL ACCIDENTS*
Authors: RICHARD H.
Published: April 2006

Abstract

The attention of everyone has already been drawn to the part which accident reports must play (Geophysical Prospecting, March, 1957, PP‐ 1 to 8). We intend to show here, with supporting examples, that the systematic analysis of the causes, does allow one to obtain practical conclusions.

To begin with, it is advisable to widen the notion of geophysical accident as much as possible. This being done, about 200 reports distributed over a long period and a sufficient number of parties, are dealt with. The collected reports are sufficiently numerous to draw conclusions in a general way bearing on the headings: drilling, transport, outbreaks of fire, explosives, falls, stings, shocks, miscellaneous causes.

All the quoted figures are referred to the number of accidents reported. Action must be taken to encourage european geophysicists to study accident reports and to analyse the causes. This may be done in such a way that secret information, such as whereabouts of their personnel, is not disclosed.

Efforts to promote “Security” must in the first place bear on the quest for the causes, the definitions of ‘accident’ and of ‘geophysicist’ being taken at their widest possible meaning.
THE INFLUENCE OF A LAYER COMPLYING WITH A LINEAR VELOCITY LAW ON THE SHAPE OF SEISMIC PULSES
Authors: MENZEL H. , ROSENBACH O.
Published: April 2006

A layer with parallel plane boundaries is assumed to have a constant density and exhibit a velocity of propagation of seismic waves which increases linearly with the distance from one boundary plane. The influence of this layer on the shape of seismic pulses is investigated in two different cases, in which:

1. The layer is embedded between two media each of which has a constant density and velocity of propagation.

2. The layer is adjacent to one medium of constant density and velocity; i.e. one boundary plane of the layer is the free surface of a two‐layered elastic half space.

Through one medium with constant velocity a plane compressional wave impinges at normal incidence on the layer complying with the linear velocity law. The incident seismic pulse is therefore split up into reflected and transmitted parts, the elastic motions of which are studied in the neighbourhood of the layer. The mathematical solution can be deduced for a general pulse by using the Laplace‐Transformation. The general solution reveals that the layer following the linear velocity law influences the shape of the reflected and transmitted pulses. This influence is discussed in detail by demonstrating some numerical examples.