Morphological changes in lung tissue in case of blunt abdominal trauma, massive blood loss, and ischemia-reperfusion of the limb

Introduction. Combined trauma remains an urgent problem in medicine because it is the leading cause of death in victims of working age. Among the main causes of death in the prehospital stage among the injured is massive blood loss and further development of organ dysfunction, including lung. In recent years, significant progress has been made in providing assistance to victims of massive blood loss, but the impact of ischemia-reperfusion of the extremities in the development of systemic changes remains unresolved.Objective of the research: to study morphological changes in lung tissue in the model of combined abdominal trauma, massive blood loss and ischemia - reperfusion of the lower extremities.Materials and methods. To conduct the experimental study used 80 adult white male rats of the Wistar line weighing 190-220 g. The experimental animals were in the standard diet of vivarium.The experimental animals were divided into the following groups: control and 3 experimental (8 animals in each group). In animals of the first experimental group under thiopental-sodium disorder (40 mg kg-1) proximal to the lower limbs was imposed hemostatic plait for a period of 120 min. In the second experimental group, a combined injury of the abdominal organs was simulated by applying two metered blows to the abdominal area; hypovolemic shock was modeled by blood flow from 20 to 22% of circulating blood volume from the femoral vessels. In the third experimental group, the combined injury of the abdominal organs, massive blood loss and reperfusion of the extremities was modeled. Animals in the control group were administered only in anesthesia.The animals of the experimental groups were removed from the experiment under conditions of thiopental sodium anesthesia by total blood flow from the heart after 1, 3 and 7 days after modeling trauma. Pulmonary tissue was collected for the study.For histological examination, the lower lobe of the right lung was removed, which was fixed in 10% formalin solution, after which the macrodrug was compacted in paraffin. Sections were obtained on a microtome followed by staining with hematoxylin eosin. After fixation of sections on individual slides studied the structure of the lungs in the study groups. Used equipment: LOMO Biolam I microscope; system of digital display of images of histological preparations. Particular attention in the study was paid to changes in the parenchyma and the main structural components of the lungs.Results and Discussion. In the simulation of ischemia-reperfusion in the early periods in animals, changes were visualized from the first day in the form of endothelial lesions, increased perivascular edema, and cellular infiltration with signs of acute inflammation up to 3 days of experiment and formation of dyslectases up to 7 days of the experiment. When modeling closed abdominal trauma and massive blood loss in the lungs, structural changes increase from the first day of the experiment in the form of a sharp decrease in blood supply, lymphoplasmic infiltration of the stroma of the interalveolar septa, and the appearance of segmental leukocytes from 1 day of the experiment. After 3 days in the lumen of the vessels appear manifestations of erythrocyte aggregation and the formation of small parietal thrombi and pronounced dystrophic-necrotic changes in pneumocytes. After 7 days of the experiment, the acute manifestations are somewhat reduced, but there are pronounced dystrophic changes of the epithelium and pronounced lympho-plasmacytic infiltration of the stroma of the interalveolar septa, dystelectasis.Closed abdominal trauma, massive blood loss, and ischemic-reperfusion syndrome in the early periods in the lungs were manifested by pronounced structural changes: thickening of the interalveolar septa due to intensive infiltration of lymphoplasmocytes, especially on day 3 of the experiment with a moderate inflammatory reaction. After 7 days of the experiment, the cellular and inflammatory infiltration of the stroma and dystrophic manifestations decreased slightly. The obtained data indicate the development of systemic changes in experimental animals and a significant increase in the possibility of developing multiple organ failure syndromes. This indicates the need for further study of the effects of reperfusion in the context of combined trauma and, accordingly, the development of effective means of correction.Conclusions. Ischemia-reperfusion of the extremities alone and in combination with other injuries causes changes in lung tissue from the first day, progression to the third day of observation and a slight decrease in manifestations up to 7 days of the experiment. The results of the study suggest that ischemia-reperfusion is an important traumatic component in combined trauma

How Retailers’ Assortment Strategies and Food Prices Are Linked: Some Empirical Evidence for Germany

The economics of grocery retailing is dominated by studies on pricing behaviour and the role of prices for thecompetitive position of retailers. Linkages to product policy have rarely been analyzed although themanagement literature indicates that an attractive assortment is one of the most important determinants ofconsumers’ store choices or even the most important one. Therefore, we raise the question how the retailers’assortments and their price level are linked. After a literature review on the role of assortments and theirinfluence on consumers and food prices, we analyze a large dataset for eight major German online retailers andtheir whole assortments of foods and beverages. It is investigated whether and how the assortments of onlineretailers affect their overall price level for foods and beverages. The econometric analysis reveals that variousindicators of retailers’ product assortments drive the price level: (i) A deeper assortment of an online retailerraises his price level of foods and beverages significantly. (ii) The organization of the website and, thus,consumers’ transaction costs, matter too. (iii) There are strong retailer-specific fixed effects on the price levelwhich may picture further assortment variables such as the breadth of the assortment or the private-labelshare

How German Online Retailers Price Foods: An Empirical Analysis for Chocolate Products

Despite the increasing importance of online grocery retailing, little is known about price dispersion across online providers, the relation between online and offline prices as well as the frequency of price adjustments. We employ means of descriptive and inductive statistics as well as panel econometrics to address these issues for German online food retailers. Daily online prices for twelve chocolate products charged by eight pure online and multichannel retailers and collected over three months are investigated. Information economics suggests that a maturing online market will call forth more price homogeneity online due to lower search costs by consumers as well as more flexible prices due to lower costs of price adjustments by retailers. Our results suggest, however, that neither homogenous prices nor frequent price adjustments do occur on the German online chocolate market

Creep resistance and structure of 10% Cr-3% Сo-2% W-0.29% Cu-0.17% Re steel with low nitrogen and high boron contents for unit components of coal power plants

The creep resistance and structure of 10% Cr-3% Сo-2% W-0.29% Cu-0.17% Re steel with 0.1% carbon, low nitrogen content and high boron content were investigated by creep rupture testing at a temperature of 650°C and stresses from 200 to 100 MPa applied in 20-MPa increment

Structural evolution of P92-type martensitic steel during creep at 650 C

Microstructure and a dispersion of secondary phase particles were examined in P92-type steel after creep test at temperature of 650 ◦C and an applied stress of 80 MPa in grip, gauge and necked portions of specimens. The structural changes in the gauge and necked sections were characterized by transformation of the tempered martensite lath structure into relatively coarse subgrain one accompanied by the coarsening of M23C6 carbides and precipitation of the Laves phase. No significant effect of creep strain on particle coarsening was foun

Yakov Polonsky as a Predecessor of the Russian Symbolism: the Poetics of the Lyrical Cycle (Polonsky’s "Dreams" and „The Life of my Friend” by Blok)

The creative heritage of Yakov Polonsky foreruns the Russian modernism on the whole and symbolism in particular in terms of both the worldview and the features of poetics. Vladimir Solovyov explained this connection by pointing to the romantic vein in the personality of the poet and to his striving for the ideal. Polonsky was the forerunner of the Russian symbolism in that he affirmed the ideal in the forms of real life. The convergence between his work and the programme of the young symbolists consisted in the absolute reliance on the image as a “symbol of the religious reality” (Aram Asoyan). The lyrical cycles by Polonsky and Blok that are discussed show a dramatic disunity of a community of people who have lost spiritual values of life. The result of this loss is suffering and death (the motive of Retribution). The moment of the highest tension in the development of the lyric plot in Polonsky’s work is the loneliness of the protagonist in the absolute darkness and emptiness of a lifeless space of a mystery. Blok shows the loneliness of his protagonist in the antithesis between the motionless “perfect order” of an ordinary life and the spontaneous movement of reminiscences, of anticipation and of thoughts, all born from dreams. Polonsky’s Dreams close with the Transfiguration achieved through obtaining a mysterious book. Blok’s cycle, in turn, ends with a sentence of suffering in the afterlife for the apostate. The analysis of the plot and motives in the two cycles makes it possible to ascertain their affinity on the level of the symbolic functioning of the motif complex of the apocalyptic plot.Творческое наследие Я. П. Полонского мировоззренчески и чертами поэтики предшествовало русскому модернизму в целом и символизму в частности. В. С. Соловьев обосновывал эту общность романтической направленностью личности поэта и ее устремленностью к идеалу. Полонский предварил русский символизм тем, что, утверждал идеальное начало в формах действительной жизни. Органичность его творчества программе младших символистов состояла в абсолютном доверии художественному образу как «символу религиозной реальности» (А. А. Асоян). В лирических циклах Полонского и Блока показана драматическая разобщенность сообщества людей, утративших духовные смыслы бытия. Следствием этой утраты становится страдание и смерть (мотив Возмездия). Наиболее напряженным моментом в развитии лирического сюжета у Полонского является одиночество героя в абсолютной темноте и пустоте безжизненного мистериального пространства. У Блока одиночество героя показано в антитезе неподвижного «отменного порядка» обыденности стихийному движению порожденных сном воспоминаний, предчувствий, мыслей. Сны Полонского завершаются мотивом Преображения через обретение тайной книги. Цикл Блока – утверждением посмертного страдания богоотступника. Сюжетно-мотивный анализ двух циклов позволяет установить их родственность на уровне символического функционирования мотивного комплекса апокалиптического сюжета.Публикация подготовлена при финансовой поддержке РФФИ, проект No 17-04-00501- ОГН-А „Литературное наследие Я. П. Полонского: исследование и комментарий” на 2019 год

Strain-induced Z-phase formation in a 9% Cr-3% Co martensitic steel during creep at elevated temperature

The size and distribution of Cr(V,Nb)N (Z-phase) particles in a 9Cr-3Co-2W-0.6Mo-0.1Ni-0.2V-0.06Nb-0.1C-0.05N-0.005B steel subjected to creep rupture test during 11,151 h at 650 °C under an applied stress of 100 MPa were studied. The replacement of V-rich (V,Nb)(C,N) carbonitrides by Z-phase was accelerated by plastic flow as suggested by a comparative analysis of these particles in different portions of crept specimen, namely, the grip section, the portion of uniform elongation, and the necked portion

On effect of rhenium on mechanical properties of a high-Cr creepresistant steel

Addition of 0.2% rhenium in the experimental steel improved the short-term creep strength at 650 C. Comparison of kinetics of tungsten depletion from the matrix in different high-Cr martensitic steels showed that rhenium in the experimental 10Cr-3Co-3W-0.2Re steel did not lead to retaining an increased amount of solute W in the ferritic matrix during both aging and creep at 650 C. At the same time, the precipitation of the high fraction of the fine Laves phase particles provided the effective particle strengthenin