sheriftawfikabbas/3oloum_corpus

The 3oloum corpus of scientific titles and abstracts

This is a corpus of titles and abstracts of 147,673 scientific articles that were scraped from the following scientific journals:

• Nature: from year 1870 to 2021
• Science: from year 1960 to 2020
• Science Advances: from year 2015 to 2020

The corpus has been created for the purpose of contributing to natural language processing (NLP) projects.

There are currently 21,309,015 words in the corpus, including the text of titles and abstracts, and excluding non-ASCII strings.

Every non-ASCII character has been replaced by the string <non_ascii> to facilitate text processing.

It is being continuously updated.

Sample data

Title	Abstract
Velocity of Light and Measurement of Interplanetary Distances	The combined availability of atomic clocks and of instrumented planetoids traveling in their own solar orbits will offer the possibility of determining their distance from us, and hence interplanetary distances, in terms of the wavelength of the radiation of atomic frequency standards. It can be anticipated that the accuracy of these measurements will be very high and will not depend upon our less accurate knowledge of the velocity of light in terms of the standard meter, the sidereal second, and so on.
High-Resolution Density Gradient Sedimentation Analysis	The principle of stability for a sample layered in a density-gradient liquid column is discussed, and a method for separating ribonucleoprotein particles by means of sedimentation in the ultracentrifuge is described.
Daily Light Sensitivity Rhythm in a Rodent	Single 10-minute light periods can cause a phase shift in the rhythm of the daily locomotor activity of flying squirrels otherwise maintained in constant darkness. A daily rhythm of sensitivity to these standard light periods was found.
Heat-Labile Serum Systems in Fresh-Water Fish	Serum specimens from 18 specimens of 12 different species of freshwater fish were examined for their ability to kill Toxoplasma nonspecifically. This ability was present in all sera except those of two of three great northern pike. The effect was destroyed by exposure to 53C, 56C, or zymosan. Complement was demonstrated in all sera except that from one great northern pike, when rabbit erythrocytes were used in the indicator system.
Chemically Induced Phenocopy of a Tomato Mutant	Lanceolate, a spontaneous leaf-shape mutant which fails to produce cotyledons and plumule in the homozygous condition, shows development if supplied with either adenine or a diffusate obtained from normal seeds. Similar development occurs in a different genetic background.
Mitotic Arrest by Deuterium Oxide	In marine invertebrate eggs, where cell divisions occur without growth, deuterium oxide produces arrest of, or serious delay in, mitosis and cytokinesis. All stages requiring assembly or operation of mechanical structures in the cytoplasm are sensitive to D.O. The block is reversible in some cells.
Nonlogarithmic Linear Titration Curves	Titration curves can be based on linear nonlogarithmic forms of the equilibrium equation of a dissociation reaction. From such curves, in contrast to those based on logarithmic transformations, both the end point of the titration and the dissociation constant can be derived.
On the Function of Corticothalamic Neurons	The effect of the synchronous discharge of a large population of corticothalamic neurons on activity within the somatosensory relay nuclei has been studied. Thalamic responses to peripheral nerve stimulation are depressed by activity in corticothalamic neurons. A subconvulsive dose of strychnine, given intravenously, changes this depression to enhancement.
Occurrence of Scandium-46 and Cesium-134 in Radioactive Fallout	Two hitherto unreported induced radionuclides, scandium-46 and cesium-134, have been detected in fallout material. Identification was made by chemical separation and gamma scintillation spectrometry. While the origin of these materials is not known, possible routes of formation from stable elements are suggested.
Degree of Obesity and Serum Cholesterol Level	No significant correlation was found between the serum cholesterol level and weight, weight corrected for frame size, or thickness of the fat shadow in medical students (mean age, 22 years).
Neural and Hypophyseal Colloid Deposition in the Collared Lemming	Feral and captive lemmings from Churchill, Manitoba, are subject to a unique pathological process in which colloidal material is deposited in bloodvessel walls at scattered points through the central nervous system. Destruction of nervous tissue at these foci is progressive, and colloidal masses in the vascular lumina of the hypothalamus appear to become fixed in the capillaries of the hypophyseal anterior lobe. Inflammatory reactions are never associated with the lesions, and the latter are larger and more numerous in older animals in warmer environments.
On Pleistocene Surface Temperatures of the North Atlantic and Arctic Oceans	Two additional interpretations are given for the important data of D. B. Ericson on the correlation of coiling directions of Globigerina pachyderma in late Pleistocene North Atlantic sediments with ocean surface temperatures. One interpretation relates the distribution of this species to the distribution and circulation of ocean water masses. On the basis of our ice-age theory, our second interpretation uses the data and correlations of Ericson to establish temperature limits of a thermal node, a line on which glacial and interglacial temperatures were equal, for the North Atlantic Ocean. This line crosses the strait between Greenland and Scandinavia. Further, Ericson9s interpretation of the 7.2C isotherm implies that the glacial-stage surface waters of the Arctic Ocean were between 0 and 3.5C.
Genetic and Environmental Control of Flowering in Trifolium repens in the Tropics	Trifolium repens at low elevations expressed wide genetic variation in tendency to flower. Clones classified as flowering or nonflowering were subjected to temperatures associated with high elevations. Flowering in "nonflowering" clones was induced under warm-day-cool-night treatments. It is proposed that in the tropics, low temperatures associated with high elevations are an important factor in determining flowering, and therefore ability to persist, in plants which are long-day and temperature sensitive.
Mammalian Liver -Glucuronidase for Hydrolysis of Steroidal Conjugates	Although the rate of hydrolysis by mammalian -glucuronidase appears to be inhibited by methylene chloride or carbon tetrachloride with the standard technique (phenolphthalein glucuronide as a substrate), the release of steroidal conjugates under conditions generally employed does not appear to be affected.
Glucuronidase Activation: Enzyme Action at an Interface	The potentiating action of chloroform on bacterial -glucuronidase has been shown to increase as the interface area between the two liquid phases increases. Prior extraction of the enzyme with chloroform causes a loss rather than an increase in activity. It is tentatively suggested that the correlation between activity and interface area may reflect a phenomenon of enzyme action at a liquid/liquid interface.
Characterization of Endogenous Ethanol in the Mammal	Ethanol has been isolated from the tissues of several animal species in amounts ranging from 23 to 145 mole/100 gm of tissue. Intestinal bacterial flora appear to be excluded as a source of this ethanol. Radioactivity from pyruvate-2-C14 appeared in ethanol after incubation with liver slices; this finding indicates an endogenous synthesis.
Reciprocal Inhibition as Indicated by a Differential Staining Reaction	Neurohistological and neurophysiological studies have shown that the bilaterally represented Mauthner9s cells in teleosts are related both structurally and functionally. The VIIIth nerve afferents, as well as the axoaxonal collaterals, display a distribution pattern which supports the concept of polar function of the neuron. Inasmuch as it is possible to alter the staining reaction of both the Mauthner9s cells by unilateral stimulation of the entering VIIIth nerve roots, it is proposed that the synaptic endings serve principally as activators and that neuronal excitation or inhibition is determined by the chemical state of the dendrites, the cell body, and the axon hillock region.
Orientation of Migratory Restlessness in the White-Crowned Sparrow	Individuals of two migratory races of white-crowned sparrows (Zonotrichia leucophrys) caged under an open sky showed a pronounced orientation in their night restlessness during normal periods of migration for the species. In August and September 1958 most birds showed a southerly orientation at night; daytime activity was random to somewhat northerly. In April and May 1959 most birds showed a strong northerly orientation at night; daytime activity was random to somewhat southerly (1).
State of Dynamic Equilibrium in Protein of Mammalian Cells	Labeled strain L cells in suspension tissue culture showed no degradation of protein when maintained in logarithmic growth. Although the protein of these cells was not in dynamic equilibrium, the conclusions cannot be transferred to the intact mammalian organism.
Mosses as Possible Sources of Antibiotics	An examination of 12 species of mosses has indicated that three produce substances capable of inhibiting the growth of various bacteria and other fungi. The method of extraction included several solvents. The extracts were not consistent in their antagonistic activity against the various species of microorganisms, nor were those that displayed antibiotic action always effective against the same organisms. Results indicate unstable products as well as physiological variation in the mosses.