scholarly journals I.—Note on a Mounted Skeleton of Ophthalmosaurus icenicus, Seeley

1915 ◽  
Vol 2 (4) ◽  
pp. 145-146 ◽  
Author(s):  
C. W. Andrews

One of the most important additions recently made to the Gallery of Fossil Reptilia at the Natural History Museum, is a mounted skeleton of the highly specialized Ichthyosaur known as Ophthalmosaurus icenicus, Seeley. This reptile presents many. peculiarities, for the most part indicating a very high degree of adaptation for life in the open sea and for rapid movement through the water, probably sometimes at considerable depths. In fact, Ophthalmosaurus may be regarded as representing among the Reptilia the swiftly swimming toothed-whales among the Mammalia, and it is interesting to note that the similar mode of life in the two cases has produced in some respects similar modifications. Thus the front paddles are enlarged, the hind ones reduced; in whales the latter have disappeared altogether. Again, there was a large caudal fin, vertical in this case, and the head was elongated, the snout sharp, and the neck so short as to be practically non-existent. The enlargement of the fore-paddles is brought about by the presence of a very large pisiform bone, which together with the radius and ulna articulates with the humerus, thus forming a very broad base for the expanded terminal portion of the paddle. Another striking peculiarity is the great reduction of the dentition, the teeth in the adult being very small and confined to the front of the jaws. Baptanodon, an American form very closely allied to, if not identical with, Ophthalmosaurus, was for a long time regarded as toothless. This reduced dentition, so unlike what is usually found in members of the group, must indicate some considerable change in the nature of the food, but what this was is unknown.

Res Publica ◽  
1970 ◽  
Vol 38 (2) ◽  
pp. 353-369
Author(s):  
Donatella Della Porta ◽  
Alberto Vannucci

The paper dealt with the control on political corruption in Italy, in particular with the reasons why most of the control mechanisms did not work for a long time, allowingfor the development of"tangentopoli". First of all, we  briefly discussed the reasons why the controls ''from below"--that is, from citizens or electors--did not function in Italy: the pervasive occupation of the administration and the civil society by the political parties, as well as "secret" agreements between political parties in order to avoid political scandals were discussed.The paper continued by analyzing two types of institutional control: the administrative controls and the judiciary controls. In the second part, we presented some main characteristics of the Italian public administration that hampered internal controls, the informal control of parties over the bureaucrats through clientelism and complicity in corruption being one among them. In the third part, we focused on the peculiar characteristics of a magistracy that enjoyed of a very high degree of format autonomy from the political power, but was "pushed" towards politics for reasons as different as complicity in corruption and the need to "substitute" for the weak policy making capacity of political parties. In the fourth part, we reviewed some (implemented of planned) reform bills to deal with the control of political corruption.


Author(s):  
Cecil E. Hall

The visualization of organic macromolecules such as proteins, nucleic acids, viruses and virus components has reached its high degree of effectiveness owing to refinements and reliability of instruments and to the invention of methods for enhancing the structure of these materials within the electron image. The latter techniques have been most important because what can be seen depends upon the molecular and atomic character of the object as modified which is rarely evident in the pristine material. Structure may thus be displayed by the arts of positive and negative staining, shadow casting, replication and other techniques. Enhancement of contrast, which delineates bounds of isolated macromolecules has been effected progressively over the years as illustrated in Figs. 1, 2, 3 and 4 by these methods. We now look to the future wondering what other visions are waiting to be seen. The instrument designers will need to exact from the arts of fabrication the performance that theory has prescribed as well as methods for phase and interference contrast with explorations of the potentialities of very high and very low voltages. Chemistry must play an increasingly important part in future progress by providing specific stain molecules of high visibility, substrates of vanishing “noise” level and means for preservation of molecular structures that usually exist in a solvated condition.


2011 ◽  
Vol E94-C (10) ◽  
pp. 1548-1556 ◽  
Author(s):  
Takana KAHO ◽  
Yo YAMAGUCHI ◽  
Kazuhiro UEHARA ◽  
Kiyomichi ARAKI

Genetics ◽  
1996 ◽  
Vol 144 (2) ◽  
pp. 635-645 ◽  
Author(s):  
David A Kirby ◽  
Wolfgang Stephan

Abstract We surveyed sequence variation and divergence for the entire 5972-bp transcriptional unit of the white gene in 15 lines of Drosophila melanogaster and one line of D. simulans. We found a very high degree of haplotypic structuring for the polymorphisms in the 3′ half of the gene, as opposed to the polymorphisms in the 5′ half. To determine the evolutionary mechanisms responsible for this pattern, we sequenced a 1612-bp segment of the white gene from an additional 33 lines of D. melanogaster from a European and a North American population. This 1612-bp segment encompasses an 834bp region of the white gene in which the polymorphisms form high frequency haplotypes that cannot be explained by a neutral equilibrium model of molecular evolution. The small number of recombinants in the 834bp region suggests epistatic selection as the cause of the haplotypic structuring, while an investigation of nucleotide diversity supports a directional selection hypothesis. A multi-locus selection model that combines features from both-hypotheses and takes the recent history of D. melanogaster into account may be the best explanation for these data.


1977 ◽  
Vol 27 (1) ◽  
pp. 81-90
Author(s):  
S.A. Filfilan ◽  
D.C. Sigee

The uptake of tritiated thymine into cells of a heterogeneous population of Prorocentrum micans was investigated using light-microscope and electron-microscope autoradiography. Specificity of thymine uptake into DNA was demonstrated by the specific removal of label from wax-embedded material using DNase and by the high degree of localization of nuclear label to chromosomes in the electron-microscope autoradiographs. All nuclei, including both dividing and non-dividing cells, showed a substantial uptake of label, indicating that nuclear DNA synthesis in Prorocentrum micans is a continuous process. The level of DNA synthesis does show considerable variation, however, with very high levels in some interphase nuclei. The continuous replication of nuclear DNA provides further evidence of dinoflagellate affinity to the prokaryotes, and indicates that Prorocentrum micans is a very primitive eukaryote cell.


Author(s):  
Arthur Yosef ◽  
Eli Shnaider ◽  
Rimona Palas ◽  
Amos Baranes

This study presents a decision-support method to estimate the next year performance of corporate Operating Income Margin (OIM). It is based on a unique combination of cross-section model and the rules-based evaluation mechanism. The estimate is done in terms of broad categories, and not precise numerical values. The model is constructed as follows: its dependent variable (OIM) is one year ahead vs. the corresponding explanatory variables. This structure of the model allows us to view explanatory variables as reflecting financial potential of corporations. The evaluation component consists of a set of rules designed to identify the companies whose “potential” clearly points to an opportunity to invest. For the method presented here to succeed, it is necessary to utilize a highly reliable modeling method, even if it is “Fuzzy”. We apply Soft Regression (SR), which is a Soft Computing modeling tool based on Fuzzy Logic, and utilize all available proxy variables by creating intervals of values. Advantages of utilizing SR, and the intervals’-based modeling are extensively discussed. Modeling results for five consecutive years are consistent and stable, thus indicating high degree of reliability. Testing indicates very high success rate for the stock market related domain, the lowest being 87.9%.


1962 ◽  
Vol 15 (3) ◽  
pp. 525-534 ◽  
Author(s):  
M. Rabinovitch ◽  
W. Plaut

The incorporation of tritiated thymidine in Amoeba proteus was reinvestigated in order to see if it could be associated with microscopically detectable structures. Staining experiments with basic dyes, including the fluorochrome acridine orange, revealed the presence of large numbers of 0.3 to 0.5 µ particles in the cytoplasm of all cells studied. The effect of nuclease digestion on the dye affinity of the particles suggests that they contain DNA as well as RNA. Centrifugation of living cells at 10,000 g leads to the sedimentation of the particles in the centrifugal third of the ameba near the nucleus. Analysis of centrifuged cells which had been incubated with H3-thymidine showed a very high degree of correlation between the location of the nucleic acid-containing granules and that of acid-insoluble, deoxyribonuclease-sensitive labeled molecules and leads to the conclusion that cytoplasmic DNA synthesis in Amoeba proteus occurs in association with these particles.


2018 ◽  
Vol 38 (1) ◽  
pp. 8-15
Author(s):  
Salim Etsouri ◽  
Ferhat Kaci ◽  
Mohamed Bouaziz

The Continental intercalary groundwater is highly sought for its water as resources hugely mobilized in Northern Sahara. A very high flow rate and output pressure characterizes this underground water. It amounts from 50 to 400 l.s-1 for the flow, and from 5 to 40 bar for pressure. A survey of the Northern Sahara Aquifer System was essential to prove the existence of this potential. This energy appears into the artesian form, which remains very considerable for a very long time in most drilling. We have realised that this energy is immense, as well as the expanded volume of the groundwater, and the importance of its use in agriculture. Unfortunately, this potential remains untapped to this day and the energy of this water is completely neglected. Several turbo generator and/or inverted pump (PATs) integration tests were undergone. The new concept of reflection with respect to the environment and sustainable development has led us to structure our work towards the extension of this potential in order to extract the exploitable energy.


1967 ◽  
Vol 113 (505) ◽  
pp. 1405-1406 ◽  
Author(s):  
A. E. Philip ◽  
J. W. McCulloch

An ecological study by Philip and McCulloch (1966) demonstrated very high correlations between the incidence of attempted suicide and the rates of incidence for repeated attempted suicide, overcrowding, having been taken into care by the local authority, having had contact as a child with the Royal Scottish Society for the Prevention of Cruelty to Children, and juvenile delinquency. McCulloch and Philip (1968) showed that persons admitted to hospital following a suicidal attempt manifested these variables to a high degree. In this latter study “juvenile delinquency” was replaced by “all offences” as a variable. The present paper reports on the relationships between a scale based on these variables and a number of psychological measures gathered from 84 of the 95 patients in the latter study.


1965 ◽  
Vol 16 (3) ◽  
pp. 985-994 ◽  
Author(s):  
Leon A. Jakobovits

On the basis of analysis of a variety of erotic literature Kronhausen and Kronhausen (1959) have suggested that there seem to be two general types: erotic realism ( ER) and hard-core obscenity ( O). Using three of the distinguishing criteria which were identified (context, exaggeration, and anti-eroticism), 20 short stories were specifically written in such a way that 10 had the characteristics of ER and the others had the characteristics of O. Study I showed a very high degree of agreement between judges in their classification of these stories as either ER or O. Study II revealed that male and female readers react differentially to the two types of stories. Females consistently rate O as more interesting and sexually stimulating than males do, the latter finding ER as more arousing than O. Other evaluational reactions are also described. A “warm-up” cumulative effect with successive reading was found with both sexes. The possibility of sampling bias affecting the data was noted.


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