Abstract
The paper presents the results of studying seeds germination capacity of two types clover and perennial ryegrass seeds under different concentrations extracts influence from the aerial part ...of perennial herbaceous plants. The data obtained indicate sustainable development possibility of the megalopolis territories when instead of lawns represented by traditional lawn grasses, stable ground covers formed from highly adaptive and characterized by increased competitive activity (allelopathic activity) of perennial herbaceous plants such as Ashweet (Aegopodium podagraria) and White dead nettle (Lamium album).
Since 2015, mechanical thrombectomy (MT) is indicated as a treatment for patients with large vessel occlusion (LVO) at the acute phase of ischemic stroke. However, the number of stroke patients ...eligible for MT is poorly known.
The objective of our study was to estimate the number of patients eligible for thrombectomy within the first 24hours of an ischemic stroke, based on the clinical National Institute of Health Stroke Scale (NIHSS).
Our study concerned all ischemic strokes which occurred between January 2013 and December 2016 recorded in the population-based Brest Stroke Registry (BSR). Based on positive predictive value and negative predictive value from articles evaluating the performance of a defined NIHSS threshold to identify LVO, we first estimated the frequency of patients with LVO and then the frequency of patients eligible for MT depending on pre-stroke modified Rankin score (mRS). Our results were extrapolated to regions of metropolitan France. Two scenarios were considered: one called “stringent criteria” with mRS ≤1 and one called “real-life” criteria with mRS ≤2.
We analyzed data from 2,025 ischemic strokes with symptom onset ≤24hours. No statistical difference between patient characteristics according to the time of hospital admission (≤6H vs. 6–24H) was observed. Based on NIHSS scores, between 23.90% and 44.20% of ischemic strokes admitted within the first six hours had LVO clinical characteristics. Among them, 14.53% to 26.87% met the ``stringent eligibility'' criteria for MT and 16.9 to 31.25% for ``real-life'' criteria. Eligible patients represented 6.32% to 11.70% of all ischemic strokes, irrespective of admission time. In France, 75 to 162 persons per million inhabitants per year were eligible for endovascular therapy, depending on including criteria. Based on activity levels recorded by the French Neuroradiology Society (SFNR) in 2018, the estimated needed increase in MT showed a heterogeneous pattern region-by-region, with the greatest need in Brittany, Pays de la Loire, and Corsica.
Based on NIHSS, our study provides coherent information concerning the estimated number of MT procedures to be performed in France: 4,877 to 10,494 ischemic strokes would be eligible each year in metropolitan France compared to the 6,596 thrombectomy procedures actually performed in 2018. Depending on the region, an estimated 10–20% to 90–100% increase in MT activity would be necessary to meet patient needs. These data suggest that there is still room for improvement in thrombectomy activity, particularly in certain regions of France, to allow equal access to MT to the entire French population.
An investigation on mechanisms of hydrogen and deuterium trapping in tungsten during irradiation by hydrogen ion plasma with oxygen impurity using the methods of thermal desorption spectrometry (TDS) ...and secondary ion mass spectrometry (SIMS) is presented in this paper. It was shown that almost 40% of trapped particles were retained in the surface oxide layer after first implantation of deuterium. Subsequent irradiation by hydrogen plasma with oxygen impurity lead to the increase of oxygen concentration and hydrogen trapping in the oxide layer and tungsten bulk. In the next cycle, which started with deuterium implantation, oxygen concentration in the oxide layer decreased and some hydrogen was removed from tungsten. Then an increase of hydrogen and oxygen concentration in the sample repeated during irradiation with ions of (H
2
+ 1 at. % O
2
) plasma. The same sequence of processes was observed during subsequent irradiation cycles.
Outstanding pediatric surgeon, scientist, teacher and health care organizer, founder of a large school of pediatric surgeons, Honored Scientist of the RSFSR (1973), academician of the USSR Academy of ...Medical Sciences (1975) and the Russian Academy of Sciences (2013), vice-president of the Russian Academy of Medical Sciences (1989–2001), laureate of two State USSR Prizes (1979, 1985) and the State Prize of the Russian Federation (1999), Chief Pediatric Surgeon of the USSR Ministry of Health (1966–1981) and the Russian Ministry of Health (1992–2005), Deputy Minister of Health of the USSR (1981–1987), Professor Yuri Fedorovich Isakov was born on June28, 1923 in Kovrov, Vladimir region. In 1966, he was elected head of the department of surgical diseases of childhood at the 2
nd
Moscow Medical Institute named after N. I. Pirogov and led it for 40 years. The surgical and scientific activities of Yuri Fedorovich were distinguished by a very wide range of areas. On the problems of thoracic surgery, extensive experience has been accumulated in the treatment of children with diseases and malformations of the neck, chest, lungs, mediastinum, and esophagus. Many diverse research works have been carried out on topical issues of abdominal surgery. Yu. F. Isakov made a very large contribution to the development of endovideosurgery in children. The clinic became one of the first in the country to create a specialized endovideosurgical service. Under the leadership of Yuri Fedorovich and with his direct participation, pediatric nephrurology and vascular surgery quickly developed, scientific research was conducted on topical issues of combined trauma of the musculoskeletal system, an anesthesiology, resuscitation and intensive care service was organized in the clinic, fundamental research was carried out on the problem of pain management in children surgery. Yu. F. Isakov was the author and co-author of more than 500 scientific works, including 23 monographs and manuals, 7 textbooks and teaching aids. At the department headed by Yuri Fedorovich, 390 dissertations were defended, including 67 doctoral dissertations. Academician Yuri Fedorovich Isakov died on August 4, 2016 and was buried at the Troekurovskoye cemetery in Moscow.
In this work, thermal-desorption spectrometry is used to study Be–W and Al–W intermetallic compounds formed on the surface of tungsten during the deposition of Be and Al atoms evaporated in the ...temperature range of 400–500 K, as well as Al atoms sputtered in argon plasma. Due to safety limitations imposed on work with beryllium in the university laboratory, most of the experiments are carried out with aluminum which is one of the proxy materials to beryllium. Regularities for the formation of intermetallics in the surface layer of tungsten during the deposition of Al and Be atoms, and in the layer formed during the joint deposition of Al and W atoms on tungsten are described. The features of the trapping of argon and hydrogen into the intermetallics are analyzed for different fluences of Al atoms deposited in plasma on the surface of tungsten, as well as for different concentrations of components in the deposition flux during the simultaneous deposition of Al and W atoms on tungsten. The features of the Al–W intermetallic formation and the nature of the retention and desorption of gases during the deposition of evaporated and plasma-sputtered aluminum atoms on tungsten are revealed. The release of a significant part of hydrogen from the Al–W intermetallic under irradiation with 50 eV ions of deuterium plasma at a temperature of 500 K is found. Most of the gases trapped by Be–W and Al–W intermetallics is desorbed in the interval of 1200–1600 K during intermetallics decomposition.
The results of study on hydrogen and deuterium trapping and retention in MPG-8 grade graphite and boron carbide coating under consecutive irradiation by deuterium and hydrogen plasma in varying ...hydrogen irradiation conditions are presented in this paper. It is shown that deuterium content decreases both in graphite and boron carbide under irradiation by hydrogen plasma. It is also shown that the main mechanism of deuterium removal is sputtering for graphite, and isotope exchange for boron carbide.
The characteristics of fine-grained graphite, which will be used as the material for plasma-contacting elements of the T-15MD tokamak, are studied in this work. The density and porosity, thermal ...diffusivity and thermal conductivity, sizes of the crystalline grains and the amount of impurities in graphite are measured. The measurement results are compared with the corresponding characteristics of MPG-6, MPG-7, and MPG-8 graphite samples. The nature of the retention of hydrogen isotopes and methane in graphite and the conditions of desorption are determined depending on the temperature of preliminary annealing, its duration, and the exposure time of annealed samples in atmospheric gas under normal conditions. The effect of irradiation with deuterium ions of various energies on the regularities of hydrogen trapping and desorption is also considered. In all cases, attention is paid to the effect of experimental conditions on the retention and desorption of hydrogen, which remained in graphite from the time of its production and was trapped during exposure to air. Based on the obtained data and taking into account the expected conditions in the chamber of the T-15MD tokamak, the optimal conditions for annealing of graphite supplied from the manufacturer are identified, and the temperatures of the tokamak elements in contact with the plasma, which contribute to the removal of hydrogen from the graphite lining, are determined.
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