Molecular nitrogen in comet 67P/Churyumov-Gerasimenko indicates a low formation temperature.

Molecular nitrogen (N2) is thought to have been the most abundant form of nitrogen in the protosolar nebula. It is the main N-bearing molecule in the atmospheres of Pluto and Triton and probably the main nitrogen reservoir from which the giant planets formed. Yet in comets, often considered the most primitive bodies in the solar system, N2 has not been detected. Here we report the direct in situ measurement of N2 in the Jupiter family comet 67P/Churyumov-Gerasimenko, made by the Rosetta Orbiter Spectrometer for Ion and Neutral Analysis mass spectrometer aboard the Rosetta spacecraft. A N2/CO ratio of (5.70 ± 0.66) × 10(-3) (2σ standard deviation of the sampled mean) corresponds to depletion by a factor of ~25.4 ± 8.9 as compared to the protosolar value. This depletion suggests that cometary grains formed at low-temperature conditions below ~30 kelvin.

Cometary science. Time variability and heterogeneity in the coma of 67P/Churyumov-Gerasimenko.

Comets contain the best-preserved material from the beginning of our planetary system. Their nuclei and comae composition reveal clues about physical and chemical conditions during the early solar system when comets formed. ROSINA (Rosetta Orbiter Spectrometer for Ion and Neutral Analysis) onboard the Rosetta spacecraft has measured the coma composition of comet 67P/Churyumov-Gerasimenko with well-sampled time resolution per rotation. Measurements were made over many comet rotation periods and a wide range of latitudes. These measurements show large fluctuations in composition in a heterogeneous coma that has diurnal and possibly seasonal variations in the major outgassing species: water, carbon monoxide, and carbon dioxide. These results indicate a complex coma-nucleus relationship where seasonal variations may be driven by temperature differences just below the comet surface.

Cometary science. 67P/Churyumov-Gerasimenko, a Jupiter family comet with a high D/H ratio.

The provenance of water and organic compounds on Earth and other terrestrial planets has been discussed for a long time without reaching a consensus. One of the best means to distinguish between different scenarios is by determining the deuterium-to-hydrogen (D/H) ratios in the reservoirs for comets and Earth's oceans. Here, we report the direct in situ measurement of the D/H ratio in the Jupiter family comet 67P/Churyumov-Gerasimenko by the ROSINA mass spectrometer aboard the European Space Agency's Rosetta spacecraft, which is found to be (5.3 ± 0.7) × 10(-4)­that is, approximately three times the terrestrial value. Previous cometary measurements and our new finding suggest a wide range of D/H ratios in the water within Jupiter family objects and preclude the idea that this reservoir is solely composed of Earth ocean-like water.

Type II Supernova Matter in a Silicon Carbide Grain from the Murchison Meteorite

The circumstellar silicon carbide (SiC) grain X57 from the Murchison meteorite contains large amounts of radiogenic calcium-44 (20 times its solar system abundance) and has an anomalous silicon isotopic composition, different from other circumstellar SiC grains. Its inferred initial 44Ti/Si and 44Ti/48Ti ratios are 1.6 x 10(-4) and 0.37. In addition, it contains radiogenic magnesium-26; the inferred initial 26Al/27Al ratio is 0.11. The isotopic and elemental data of X57 can be explained by selective mixing of matter from different zones of a typical type II supernova of 25 solar masses during its explosion. The high 44Ti/Si ratio requires contributions from the innermost nickel zone of the supernova to the SiC condensation site, as similarly suggested by astronomical observations.

Small SiC grains and a nitride grain of circumstellar origin from the Murchison meteorite: implications for stellar evolution and nucleosynthesis.

We report the results of SIMS isotopic analyses of carbon, nitrogen, oxygen, and silicon made on 849 small (approximately 1 micrometer) individual silicon carbide grains from the Murchison meteorite. The isotopic compositions of the major elements carbon and silicon of most grains (mainstream) are similar to those observed in larger grain studies suggesting an AGB star origin of these grains. In contrast, the trace element nitrogen shows a clear dependency on grain size. 14N/15N ratios increase with decreasing grain size, suggesting different stellar sources for grains of different size. Typically observed 14N/15N ratios in the small grains of this study are approximately 2700, clearly larger than the values expected from model calculations of AGB stars. In addition to the three dredge-up episodes characteristic for the evolution of AGB stars, extra-mixing of CNO-processed matter in low mass AGB stars appears to be a promising possibility in order to explain the high 14N/15N ratios of the small circumstellar SiC grains. A small fraction of grains shows a silicon isotopic signature not observed in larger circumstellar SiC grains from Murchison. Their stellar origin is still uncertain. The minor type A, B, Y, and X grains were found to be present at a level of a percent, which is similar to their abundance in the larger-grain SiC separates from Murchison. Oxygen isotopic compositions are normal within the experimental uncertainties of several 10%, indicating that oxygen of stellar origin is rare or even absent in the SiC grains. We conclude that most of the oxygen is a contaminant which was introduced into the SiC grains after their formation, e.g., during sample processing in the laboratory. We identified a nitride grain, most likely Si3N4 with little carbon, with highly anomalous isotopic compositions (12C/13C = 157 +/- 33, 14N/15N = 18 +/- 1, delta 29 Si = -43 +/- 56%, delta 30 Si = -271 +/- 50%). The isotopic patterns of carbon, nitrogen, and silicon resemble those of the rare SiC X grains suggesting that these two rare constituents of circumstellar matter formed in the same type of stellar source, namely, Type II supernovae.

[A case of metastasis of the esophageal adenocarcinoma to the middle ear]. / Przypadek przerzutu gruczolakoraka wpustu do ucha srodkowego.

The authors have presented the rare case of metastasis the cardiac adenocarcinoma to the middle ear. They have described occurrence of metastatic tumors of the temporal bone, mechanisms of their formation, clinical picture, diagnostic difficulties, prognosis and ways of therapy. A radical surgical treatment and chemotherapy have been used in this case. The patient died 17 months after diagnosis of the cardiac adenocarcinoma and 10 months after diagnosis of metastasis to the temporal bone.

[Results of treatment for lip carcinoma]. / Wyniki leczenia raka wargi.

233 patients with lip carcinoma were treated in ENT Department of County Hospital No 1 in Rzeszów from 1974 to 1990. Analysing the kind of surgery according to clinical stage of the disease it was stated that the most patients with advanced tumors required reconstruction operations-125 (53.6%). Authors analyzed 3, 5 and 10 years survivals, separately for patients treated either surgically or with combined method and for patients who were treated with radiotherapy followed by surgery because of local recurrence of the disease.

Distribution and dynamics of rural population in Central Eastern Europe in the 20th century.

This is an analysis of rural population trends in Central Eastern Europe during the twentieth century. The region is defined as including "Estonia, Latvia, Lithuania, the Kaliningrad District, Belarus, Ukraine, Poland, Czechoslovakia, Hungary, Rumania, Moldavia, Bulgaria and Yugoslavia....For each of them the size of rural population and its density have been evaluated, and then, the dynamics of demographic evolution described. An important part of the analysis has been the comparison of rural population to total population. On the basis of this comparison, structural changes and demographic trends have been defined. Particular attention has been paid to the processes of depopulation as well as their range and intensity in rural areas of Central Eastern Europe."

[The number and distribution of the Polish population in Ukraine in the twentieth century]. / Liczba i rozmieszczenie ludnosci polskiej na Ukrainie w XX wieku.

PIP: "The paper presents the number and distribution of Polish population in present Ukrainian territory in the twentieth century. The introduction includes historical information about background and history of Polish population in earlier periods.... The changes caused by World War [II] including changes of the borders [are then] evaluated.... The assessment of war losses is followed by post-war demographic analysis. The next part of the paper is the interpretation of the data of 1959 and 1989 Russian Censuses. The number of Polish population in static and dynamic aspects is presented. Besides the national statistics, the data on mother-tongue were considered. The scale and intensification of sovietization and russification processes are demonstrated, as well as their influence on national consciousness of Poles." (EXCERPT)^ieng

[The demographic consequences of famine in Ukraine in the twentieth century]. / Konsekwencje demograficzne wielkiego glodu na Ukrainie w latach trzydziestych XX wieku.

PIP: "The demographic situation of [the] Ukrainian SSR in the thirties is [analyzed]...based on 1926 National Census and 1937 National Census.... It was attempted to determine as precisely as possible the demographic losses caused by collectivization of Ukrainian agriculture. Dispossession of wealthy peasants, deportation and famine resulted in [the] death of several million persons.... The author discusses the political, national and social consequences of this great demographic catastrophe." (EXCERPT)^ieng

Ultrathin-layer polyacrylamide gel isoelectric focusing for the identification of hemoglobin variants.

An ultrathin-layer polyacrylamide gel isoelectric focusing method for typing hemoglobin is described. This method, which uses Pharmalyte pH 6.7-7.7 and an electrode wick distance of 5.0 cm, clearly resolves the A, F, S, C and a number of rare variant allelic products. The technique is ideal for rapid screening of a large number of fresh blood and/or bloodstained samples.

Lymphocyte subpopulations in the blood and cerebrospinal fluid of multiple sclerosis patients in active disease.

Lymphocyte subpopulations (total T cells, active T cells and B cells) were simultaneously analyzed in peripheral blood and CSF of MS patients. All patients were in active disease, 3 to 4 weeks after first signs of disease activation appeared. Per cent levels and absolute numbers of examined lymphocyte subpopulations in the blood of MS patients were significantly lower than in healthy controls. In MS, the level of active T lymphocytes was lower in CSF than in peripheral blood. The results support our earlier observations relating to the role of active T lymphocytes in the clinical course of disease.

Neutron-induced fission of uranium: a dating method for lunar surface material.

Volcanic glasses collected on the rim of Shorty Crater in the Apollo 17 area were formed 3.63 x 10(9) years ago. The amounts of xenon-136 produced by neutron-induced fission of uranium-235 indicate that the glasses resided on the lunar surface for about 38 million years before they were deeply buried. The glass spherules were reexcavated by the impact that formed Shorty Crater 17 million years ago, and remained undisturbed until they were collected.

Trapped solar wind noble gases, kr81/kr exposure ages and k/ar ages in apollo 11 lunar material.

Grain size and etching experiments show that the fine lunar material contains large amounts of trapped solar wind particles. Elemental and isotopic compositions of the noble gases in solar material and in the terrestrial atmosphere are significantly different, except for the Ar(36)/ Ar(38) and the Kr isotope ratios. Exposure ages of two rocks and of the fine material are between 380 and 510 x 10(6) years. Feldspar concentrates give K/Ar ages of 3220 and 3300 x 10(6) years, significantly higher than the unseparated rock.

Apollo 11 solar wind composition experiment: first results.

The helium-4 solar wind flux during the Apollo 11 lunar surface excursion was (6.3 +/- 1.2) x 10(6) atoms per square centimeter per second. The solar wind direction and energy are essentially not perturbed by the moon. Evidence for a lunar solar wind albedo was found.