scholarly journals Shell form in Venerupis rhomboides

1961 ◽  
Vol 41 (3) ◽  
pp. 705-722 ◽  
Author(s):  
N. A. Holme
Keyword(s):  
Shell Height ◽  
Single Species ◽  
Significant Negative Correlation ◽  
Small Samples ◽  
Logarithmic Scale ◽  
Sea Floor ◽  
Probability Paper ◽  
Straight Line ◽  
Two Samples ◽  
Rates Of Growth

SUMMARYTwo forms of Venerupis rhomboides occur in Plymouth waters. A more slender form, corresponding to that described by Pennant, occurs in the Eddystone shell gravel, and a more robust form, corresponding to the Venus sarniensis of Turton, occurs at the mouth of the River Yealm. The two forms differ in ratios of shell height, width and lunule width relative to shell length. A population with intermediate ratios is found at 6-5 m in Plymouth Sound.Plots of height/length ratios of these and another intermediate sample on probability paper did not indicate that the intermediate populations were composed of mixtures of the two extreme forms, and it was provisionally concluded that these were all variants of a single species.If the height/length ratios of series of samples from different localities are plotted against depth of water on a logarithmic scale, an inverse relationship, approaching a straight line, is obtained. Regression lines for median ratios in the 3-4 and 4-5 cm length groups have been plotted separately, as there is some change in proportion with increasing length. These show a highly significant negative correlation between shell ratios and depth.From the regression lines it has been possible to obtain an estimate of the depth inhabited by even quite small samples of shells. Depth estimations have been made for eight samples, consisting mainly of dead shells. Six samples lay within the expected limits, and discrepancies in the other two samples are attributed to transport along the sea floor.The possible causes of the differences in shell ratios are discussed. Previous work suggests that shell ratios may be affected by different rates of growth. Soil grade, temperature, food supply, and light penetration are considered unlikely causes of the observed differences in shell ratios, and it is suggested that the pattern of growth may be affected by pressure.The Appendix contains a key to British species of Venerupis.

Is the Gaussian Distribution Normal?

1965 ◽  
Vol 18 (1) ◽  
pp. 65-71 ◽  
Author(s):  
E. W. Anderson
Keyword(s):  
Normal Distribution ◽  
Gaussian Distribution ◽  
Mathematical Foundation ◽  
Probability Paper ◽  
Straight Line

It has been said that the mathematician accepts the gaussian distribution because he believes it to be supported in practice, and the practical man accepts it because he believes it has a sound mathematical foundation. Presumably it is for such reasons that the gaussian distribution is known as the ‘normal’ distribution and ‘probability paper’ has scales specially distorted so that a gaussian distribution will appear as a straight line.

Chemical prediction of water activity in processed cheese

1989 ◽  
Vol 56 (4) ◽  
pp. 665-668 ◽  
Author(s):  
María A. Esteban ◽  
Andrés Marcos
Keyword(s):  
Regression Analysis ◽  
Linear Regression ◽  
Water Activity ◽  
Negative Correlation ◽  
Linear Regression Analysis ◽  
Significant Negative Correlation ◽  
Regression Equation ◽  
Low Fat ◽  
Two Samples ◽  
The Mean

SummaryBy linear regression analysis, a highly significant negative correlation (r = −0·96) was found between the mean ash concentration values (g/100 g moisture) and water activity (aw) of six types of processed cheeses (low-fat, semi-fat, fat, extra-fat, double fat and special). The regression equation aw = 0·9951 − 0·0032* (ash), applied to 40 cheese samples, yielded aw values which differed by < 0·005 aw units from those measured experimentally in 75% of the samples. The maximum differences between the calculated and experimental aw values (found in only two samples) were ±0·01 aw units.

Velocity estimates derived from three‐dimensional seismic data

Geophysics ◽  
1983 ◽  
Vol 48 (11) ◽  
pp. 1486-1497 ◽  
Author(s):  
Kwame Owusu ◽  
G. H. F. Gardner ◽  
Wulf F. Massell
Keyword(s):  
Seismic Data ◽  
Constant Velocity ◽  
Three Dimensional ◽  
Logarithmic Scale ◽  
Model Data ◽  
Reconstruction Process ◽  
Input Field ◽  
Scattering Center ◽  
Straight Line ◽  
The Matrix

A new computer algorithm is described by which velocity estimates can be derived from three‐dimensional (3-D) multifold seismic data. The velocity estimate, referred to as “imaging velocity,” is that which best describes the diffraction hyperboloid due to a scatterer. The scattering center is best imaged when this velocity is used in the reconstruction process. The method is based on the 3-D Kirchhoff summation migration before stack. The implementation consists of two basic phases: (1) differentiating the input field traces and resampling them to a logarithmic time scale, and (2) shifting, weighting, and summing each resampled trace to a range of depth levels also chosen on a logarithmic scale. Peak amplitudes in the resulting image matrix give a time T and depth Z from which velocity is obtained using the relation [Formula: see text] The locus of constant velocity is a slanted straight line in the coordinate system of the matrix. In the usual application of migration for velocity analysis, each input trace of N samples is migrated for each of M constant velocity functions requiring [Formula: see text] moveout shift calculations. In the new method presented here, a constant shift is calculated for a given resampled trace, for each depth into which it is summed. This reduces the number of calculations per trace to about N, resulting in a significant improvement in computing efficiency. The operation of the algorithm is illustrated using synthetic and physical model data.

scholarly journals Identifikasi Kekeliruan Penggunaan Metode Statistika pada Artikel yang Dimuat di Jurnal OJS Unud

2019 ◽  
Vol 9 (1) ◽  
pp. 26
Author(s):  
Ni Luh Putu Suciptawati
Keyword(s):  
Statistical Methods ◽  
Linear Regression Analysis ◽  
Multiple Linear Regression Analysis ◽  
Ordinal Scale ◽  
Small Samples ◽  
Research Use ◽  
Chi Square ◽  
Inappropriate Use ◽  
Two Samples ◽  
Chi Square Test

Abstract:  The statistical method plays a role in scientific research. Use of appropriate statistical methods in analyzing  data influences research conclusions. Misuse  statistical methods will lead to incorrect conclusions. This study aims to identify the misuse of statistical methods in articles published in the OJS UNUD Journals. We reviewed 97 articles from OJS UNUD Journals published in 2017. This study  found several  misuse statistical methods these included: misuse multiple linear regression analysis, generalize conclusions based on descriptive statistics, inappropriate use of  ANOVA, misinterpretation of negative correlation values, use of Chi square test for small samples, use of t-test two samples for observations with ordinal scale Keywords: statistical methods, misuse statistical, OJS UNUD Journal

scholarly journals THE USE OF PRECIPITIN ANALYSIS IN AGAR FOR THE STUDY OF HUMAN STREPTOCOCCAL INFECTIONS

1955 ◽  
Vol 101 (5) ◽  
pp. 539-556 ◽  
Author(s):  
Seymour P. Halbert ◽  
Lois Swick ◽  
Constance Sonn
Keyword(s):  
Guinea Pig ◽  
Gamma Globulin ◽  
Logarithmic Scale ◽  
Migration Rates ◽  
Strong Trend ◽  
Streptolysin O ◽  
Straight Line ◽  
Human Sera ◽  
Human Gamma Globulin ◽  
Line Relationship

Using a highly concentrated and partially purified streptolysin O preparation, migrating agar precipitins have been found in 94 of 143 human sera from patients with a variety of diseases. Most of those showing no bands, had very low antistreptolysin titers. A correlation was found between the migration rates of these bands and the antistreptolysin titer. A strong trend toward a straight line relationship was apparent when the ASO titers were plotted on a logarithmic scale. In addition, a roughly positive correlation was found between the intensity of these bands and the antistreptolysin O titers. The finding of high levels of antistreptolysin O activity and slowly migrating heavy bands in normal pooled human gamma globulin supported the above observations. Very similar results were obtained with rabbit and guinea pig sera after immunization with the streptolysin O concentrates. The data strongly indicate that antistreptolysin O activity in human sera is generally due to precipitating antibody, and that non-specific inhibitors are not usually involved, even with low titered sera. Rabbit and guinea pig antisera to the oxidized inactive and to the reduced active forms of streptolysin O showed no obvious differences. Attempts to demonstrate immunological differences between the two states of streptolysin were apparently complicated by proteolysis, due to contamination of the concentrates with proteinase precursor.

scholarly journals The Biomass of the Bottom Fauna in the English Channel off Plymouth

1953 ◽  
Vol 32 (1) ◽  
pp. 1-49 ◽  
Author(s):  
N. A. Holme
Keyword(s):  
Statistical Analysis ◽  
Total Weight ◽  
Bottom Fauna ◽  
English Channel ◽  
Physical Conditions ◽  
Straight Line ◽  
Two Samples ◽  
Quantitative Sample ◽  
Line Relationship

A survey has been made of the biomass of the macrobenthos at twenty stations in the English Channel off Plymouth. The object was to provide a basis for following long-term fluctuations in the fauna.A brief survey of physical conditions in the area is given, and a gradeanalysis of the soil at each station has been made.Core-samples show that the sediment is shallow in many places and rock has been taken at 36 cm. or less below the surface at a number of stations.Samples totalling ½m.2 were taken at each station with a modified 'scoopsampler', covering 1/10m.2, which is briefly described.Sources of error in sampling are considered in detail. Some species may evade the sampler and others live too deep in the sediment to be taken. A comparison against a Petersen grab and a new ' suction-corer' show that the scoop-sampler does take a reasonably quantitative sample. The number of species taken in successive hauls, when plotted against the log of the area sampled, approaches a straight-line relationship similar to that obtained by Williams (1950).A statistical analysis is made of a series of samples taken at one station, and the variance between the two samples in each haul and between successive hauls calculated. At this pàrticular station the fauna in successive samples is shown to be fairly random.A sieve of 2-2 mm. mesh was employed. Compared with a finer sieve losses in terms of numbers may be quite large, but the total weight taken is little affected.

Changes in insect populations in the field in relation to preceding weather conditions

1951 ◽  
Vol 138 (890) ◽  
pp. 130-156 ◽  
Keyword(s):  
Minimum Temperature ◽  
Population Change ◽  
Geometric Mean ◽  
Light Trap ◽  
Population Level ◽  
Weather Conditions ◽  
Single Species ◽  
Great Accuracy ◽  
Insect Population ◽  
Logarithmic Scale

An attempt has been made to measure changes in a mixed insect population under natural conditions in the field, and to see to what extent they are quantitatively related to previous weather conditions. To obtain a measure of the population, insects were caught in a light-trap at Harpenden, about 25 miles north of London, every night for four years from 1933 to 1937, and again for four years from 1946 to 1950. In all about 1,440,000 insects, mostly Diptera, were captured on about 2850 nights. The measure of population level in any one month was the geometric mean catch per night, obtained by calculating the arithmetic mean of log ( n + 1), where n is the number of insects caught in one night. This figure has to be corrected for the effect of prevailing weather conditions on activity. The departure of each month, on the logarithmic scale, from the average value for all repetitions of the same month gives a measure of how the population in this particular month is differing from the level to be expected for that time of the year. These departures were then made the basis of six-factor multiple regressions, in which the population change was the dependent variable, and the rainfall and minimum temperature departures from normal in each of the three preceding months were the independent variables. It is shown that a very high proportion of the mean changes of the population in the field can be accounted for by the effect of rainfall and minimum temperature in the three previous months. An examination of the regressions in the different seasons shows that rainfall has a high positive effect in the summer and autumn but little or no effect in the winter. Minimum temperature, on the contrary, has its lowest effect in the summer, so that the relation between population and minimum temperature one month previous is negative in the summer, and with temperature two months previous is negative in the autumn. The analysis of the available data has so far only been carried out on the total insect population, against rainfall and minimum temperature. Work is continuing on other weather conditions, other time intervals, and also on special groups of insects, but it is unlikely that the method can be applied with any great accuracy in the near future to single species of insects.

scholarly journals Paracoccidioides cerebriformis Moore, 1935. MYCOLOGIC AND IMMUNOCHEMICAL STUDY

1997 ◽  
Vol 39 (3) ◽  
pp. 141-144 ◽  
Author(s):  
Carlos da Silva LACAZ ◽  
Mônica Scarpelli Martinelli VIDAL ◽  
Cristiane Neves PEREIRA ◽  
Elizabeth Maria HEINS-VACCARI ◽  
Natalina Takahashi de MELO ◽  
...  
Keyword(s):  
Molecular Biology ◽  
Western Blotting ◽  
Guinea Pigs ◽  
Paracoccidioides Brasiliensis ◽  
Single Species ◽  
Sao Paulo ◽  
Immunochemical Study ◽  
Sds Page ◽  
Two Samples ◽  
De Medicina

The present study concern on mycologic and immunochemical data obtained from two samples of a fungus considered as belonging to the species Paracoccidioides cerebriformis described by Moore in 1935, and maintained since then on Sabouraud’s agar in the mycology collection of the Instituto de Medicina Tropical de São Paulo. After 60 years, the samples exhibited the same characteristics described by Moore (1935). However, experimental lesions did not resulted in guinea-pigs inoculated intratesticularly. The dominant antigen in Paracoccidioides brasiliensis, 43 kDa glicoprotein (gp43), could not be demonstrated by SDS PAGE and Western blotting. Immunoelectrophoresis did not demonstrated the E arch of cathodic migration using a policlonal anti gp43 serum. According to these findings, it is concluded that the fungus described by Moore (1935) as P. cerebriformis does not belong to the genus Paracoccidioides. Paracoccidioidomycosis should therefore be considered as resulting from infection by a single species, Paracoccidioides brasiliensis (Splendore, 1912) as asserted by Almeida (1930). Further studies, through molecular biology methods, could identify the mentioned fungus

Organic and siliceous protistan scales in north-east Atlantic abyssal sediments

2006 ◽  
Vol 86 (4) ◽  
pp. 679-688 ◽  
Author(s):  
Andrew J. Gooday ◽  
Genoveva F. Esteban ◽  
Ken J. Clarke
Keyword(s):  
Deep Sea ◽  
Small Samples ◽  
Heterotrophic Flagellate ◽  
Heterotrophic Flagellates ◽  
East Atlantic ◽  
Sea Floor ◽  
North East ◽  
The North ◽  
Marine Habitats ◽  
Deep Sea Sediments

We report the occurrence of a high diversity of minute (∼1 μm diameter) organic and siliceous protistan scales in small samples (total volume ∼35 μl) of superficial sediment from the Porcupine Abyssal Plain (PAP), north-east Atlantic (4850 m water depth). Many exhibit characters by which they can be identified to species. The organic scales belong to the haptophyte genera Chrysochromulina (8–9 species), Chrysocampanula and Dolichomastix (1 species each). The siliceous scales belong to the chrysophytes Paraphysomonas vestita and Meringosphaera sp. and to the heterotrophic flagellate genus Thaumatomastix (T. dybsoeana, T. formosa, Thaumatomastix sp.). As far as we are aware, this is the first time that non-calcareous protistan scales have been observed in deep-sea sediments (although siliceous skeletal plates and cysts are reported). All scales probably originated from the upper water column and were delivered to the deep-sea floor on rapidly sinking detrital aggregates. However, naked heterotrophic flagellates are known to thrive in abyssal sediment habitats and so the possibility that some scale-bearing protists also live in benthic deep-sea environments cannot be eliminated. Many species identified at the PAP site are common in coastal marine waters around Europe; some occur as far afield as Tasmania and New Zealand. Five Chrysochromulina species are known from central oceanic areas, including parts of the North Atlantic, while another species, C. pringsheimii, is reported from a British freshwater lake. We retrieved ∼15% of the 55 named Chrysochromulina species (∼8% of the estimated total number of species in this diverse group) in the ∼35 μl of abyssal sediment. Because the scales can persist and be identified after cell death, they may provide useful time- and space-averaged information about the distribution of protist species in marine habitats. The long-term fate of the scales on the sea-floor is unknown. It is possible that at least some of the organic scales are preserved as microfossils in deep-sea sediments.

An apparent inconsistency arising from tests of significance based on fiducial distributions of unknown parameters

1939 ◽  
Vol 35 (4) ◽  
pp. 579-591 ◽  
Author(s):  
F. Yates
Keyword(s):  
Prior Knowledge ◽  
Relevant Information ◽  
Small Samples ◽  
Weighted Mean ◽  
Unknown Parameters ◽  
Fisher Test ◽  
Tests Of Significance ◽  
Two Samples ◽  
Apparent Inconsistency ◽  
The Difference

It has been observed that the Behrens and Fisher test of the difference of the means of two samples gives a smaller percentage of significant results than might be expected on the analogy of the ordinary t test with a pooled estimate of variance. The cause of this apparent anomaly is explained, and it is shown that the criticisms of the test to which the anomaly has given rise have their origin in (a) neglect of the relevant information provided by the estimated values of the variances, and (b) an insufficient appreciation of the fiducial basis of all tests of significance (including the ordinary t test) on small samples.It is pointed out that Sukhatme's table (constructed for the Behrens and Fisher test) also provides a test for the weighted mean of the means of two sets of observations, concerning whose relative accuracy no prior knowledge is available.

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