Development of the interatrial wall during the ontogenesis of foetuses and children up to one year of age

Background: The foramen ovale, present in foetal interatrial septum, plays an important role during foetal life. During delivery, foramen ovale closes and becomes fossa ovalis, starting the pulmonary circulation. The aim of our study was to describe the growth of the interatrial wall and changes in location of the foramen ovale, and fossa ovalis during the ontogenesis in the human hearts.Materials and methods: The study was performed on post-mortem material obtained from 92 human hearts from 22nd week of foetal life up to 1 year of age, fixed in a 4% formalin solution.Results: The interatrial wall size in the studied development period was greater in the horizontal than in the vertical dimension. During ontogenesis up to 1 year old, the anterior and inferior parts of the interatrial wall increased their shares considerably by 8% and 6%, respectively. The percentage participation of foramen ovale in the interatrial wall construction in the foetal period formed more than 50% of its size and fairly decreased reaching in infants about 39%.Conclusions: Our study demonstrated that during ontogenesis, from the foetal period to infancy, the parts of the interatrial wall increase their dimensions unevenly. The foramen ovale growth is smaller, compared to the rest of the interatrial wall development. On the basis of our data we can assume that the foramen ovale centre tends to be found in the postero-inferior quadrant of the interatrial wall (foetuses) and in postero-superior quadrant of the interatrial wall — in infants

Arterial hypertension and remodeling of the right ventricle

Background: In case of long-term and physiological loads (e.g. during pregnancy or regular athletics training), reversible morphological changes occur in the heart - cardiomyocytes undergo hypertrophy, however, this is not accompanied by impairment of left ventricular function or myocyte metabolism. However, in the course of various pathological processes, as time goes by, gradually permanent morphological changes occur. These changes are referred to as remodeling of the heart muscle, which, regardless of the primary cause, can lead to the development of chronic heart failure. Materials and methods: The study was performed on post-mortem material of 35 human hearts obtained from forensic sections and anatomopathological sections of people who died of non-cardiac causes (mainly traffic accidents, suicide attempts, strokes, acute infections); material was fixed in a 4% formalin solution. The hearts were subjected to macro- and microscopic assessment. During microscopic assessment the features of remodeling were evaluated. Results and conclusions: In vivo and echocardiographic tests, as well as macroscopic evaluation of post-mortem material, suggest the presence of some kind of right ventricular muscle remodeling, however classic microscopic observations, presented in this study do not provide such unambiguous evidence. Thus, the question arises: why and how the right ventricular function is disturbed, sometimes at early stages of arterial hypertension

Experimental analysis of gravitational heat pipe using R507 as a working fluid

The paper presents possibility of using R507 as a working fluid in gravitational heat pipe. The outcome of experimental analysis are compared to the results obtained with mathematical model. The simulations allow to calculate fluid and wall temperatures in the thermosyphon. The model equations contain the formulas for boiling and condensing heat transfer coefficients. Proposed new model is in good agreement with real operation of the device, especially at the steady state. There are discrepancies during the start-up process, but the differences between the results obtained by the model and experiments do not exceed 5% at the steady state. The thermal efficiency of the thermosyphon is also determined as 0.63

The possibilities if implementing clean coal technologies in the brown coal industry in Poland

Polityka klimatyczna UE ulega ciągle stopniowym modyfikacjom związanym z różnym pojmowaniem ochrony klimatu przez kraje członkowskie i kosztom związanym z jej realizacją w poszczególnych krajach. Jednak jej cele są stałe: ograniczenie emisji gazów cieplarnianych do atmosfery, zmniejszenie energochłonności gospodarek oraz zwiększenie udziału energii odnawialnej. Niezależnie od ostatecznego kształtu pakietu energetyczno-klimatycznego UE branża węgla brunatnego w Polsce będzie musiała przygotować się do jego skutków. W tym celu konieczne będzie wdrożenie tzw. "czystych technologii węglowych" oraz rozszerzenie kierunków wykorzystania węgla brunatnego. W artykule dokonano przeglądu dostępnych i perspektywicznych technologii węglowych, których wdrożenie w Polsce umożliwiłoby redukcję emisji CO2. Szczególny nacisk położono na zwiększenie sprawności bloków energetycznych spalających węgiel brunatny, wychwytywanie i składowanie dwutlenku węgla oraz zgazowanie naziemne i podziemne złóż tego surowca. Wskazano także przyszłe kierunki badań nad rozwijaniem technologii najkorzystniejszych w polskich warunkach, uwzględniając przy tym względy środowiskowe, ekonomiczne i techniczne.The climatic policy of EU is being gradually modified because of different understanding of the climate protection in member countries and because of the costs related to its implementation in particular states. However its goals are constant: reduction of greenhouse gases to the atmosphere, reducing the power consumption and increasing the participation of renewable energy sources. Independently of the final form of EU's energy-climate package the brown coal industry in Poland has to prepare for its consequences. Therefore it is necessary to implement so called "clean coal technologies" and expand the directions of brown coal usage. The article describes available and perspective coal technologies that - if implemented - would allow to decrease CO2 emissions in Poland. The particular emphasis is put on: increasing the efficiency of power units running on brown coal, capture and storage of carbon dioxide as well as both underground and surface gasification of brown coal deposits. Future research directions over developing the most favorable in Polish conditions are shown, taking environmental, economical and technical considerations into account

Impact of potential climate changes on competitive ability of main forest tree species in Poland

An influence of environmental changes upon forest tree species competition was studied for suggested scenario of environmental changes (3−4°C increase of monthly temperatures), 8 main tree species and 6 natural regions. For a synthetic assessment of the reaction of various species for thermal and higric parameters of the climate, the growth multipliers DDGF and SMGF were used. The main environmental factor influencing future growth of tree species in Poland will be water shortage due to increased evapotranspiration. Regional decrease of water sensitive species importance, eg. alder, spruce and birch, accompanied by country−scale expansion of highly competitive, late−successional species, eg. beech and hornbeam is expected

Working support systems for surface mining on the example of Sierra Gorda mine in Chile

W artykule przedstawiono przykłady systemów wspomagania pracy kopalni odkrywkowej, jakie wdrożono w jednej z najmłodszych i zarazem najnowocześniejszych kopalń rud miedzi w Chile, tj. w kopalni Sierra Gorda, której współwłaścicielem jest KGHM International Ltd. W artykule wybrano najważniejsze z nich z punktu widzenia możliwości zaimplementowania ich w górnictwie odkrywkowym w Polsce.This paper presents the examples of working support systems for surface mines, which have been implemented in one of the youngest and the most modern copper ore mine in Chile – Sierra Gorda co-owned by KGHM International Ltd. The most important systems have been presented from the point of view of the possibility of their implementation in Polish surface mines