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This study aims to evaluate the validity of Fractional Advection-Dispersion equation (FADE) in breakthrough curves in saturated homogenous soil media, i.e. clay, and to examine the three primary restraints, pore water velocity, dispersion coefficient, and order of fractional differentiation which are impacting solute transport behavior (Fickian or Non-Fickian). In this study, the FADE framework used to characterize the transport process at depth 50 cm soil (clay). FADE Main based on FORTRAN, to estimate the parameters of FADE including fractional differentiation (λ), the dispersive coefficient (D), and the average pore-water velocity (v). If the value of is equal to or greater than 2, the transport is said to be Fickian otherwise is non-Fickian. In this study, the fractional differentiation of non-Fickian behavior was found 1.85 which is less than 2. On the other hand, early long-time tailing to the soil media showed an increase in the dispersion coefficient (D) for FADE and higher values in differentiation coefficient (λ = 1.85–1.99). The results of breakthrough curves (BTCs) of relative concentration (C/C0) show that it is best fitted by using FADE. For the assessment of fitting, Root Mean Square Error (RMSE) and determination Coefficient was used to find the quality of fit.[Formula: see text] .

The article presents studies devoted to the practical application of computer X-ray microtomography (micro-CT) in oilfield geology. In particular, the authors give results of using the method for sample defectoscopy before petrophysical studies in order to improve the quality of analyzes. The paper includes an example of assessing the depth of core plugging with drilling fluid; assessing the mineral composition by micro-CT; experimental core studies when modeling the thermal effect on the oil source rocks of the Bazhenov formation. The authors also examine the current state of research in the field of digital petrophysics or digital core. The study is aimed at introducing the micro-CT method into the oilfield process.

In this review we have briefly reviewed the state of the art of “digital core” technology. In particular, we reviewed the main artefacts that can occur in the analysis of rocks by computed X-ray microtomography. Next, we highlighted the existing approaches of direct mathematical modelling of core filtration characteristics using digital model and poroset models. Literature analysis has shown that the most justified in the ratio of required technical resources (computer power) and reliability of results is the integrated approach. Unfortunately, when calculating phase permeabilities using digital core models, it is necessary to calibrate simulation results using standard laboratory methods. We also analysed some approaches to modelling enhanced oil recovery methods such as hydrochloric acid and hydraulic fracturing, as well as thermal stimulation of oil matrix rocks. In conclusion, we noted that the main challenge of today’s “digital core” technology is reliable calculation of phase permeabilities, and further development of the technology should be towards 4D modelling of EOR methods using digital core models.

The aim. To assess the hemodynamic parameters of the hepatic and visceral blood flow in patients with compensated and decompensated liver cirrhosis. Materials and methods. 290 patients with liver cirrhosis were examined: 206 had gastrointestinal bleeding, 84 had diuretic-resistant ascites. Ultrasonic scanning, Doppler sonography, esophagogastroduodenoscopy, angiography, radioisotope scintigraphy were performed to assess blood flow in the portal, splenic and superior mesenteric veins and in the hepatic, splenic and superior mesenteric arteries. Results. Change in the hepatic microcirculatory blood flow in the natural course of liver cirrhosis was characterized by decreased portal and increased arterial blood flow, “arterialization” of hepatic blood flow based on scintigraphy. Decompensation of the disease was associated with progressive reduction in both portal and arterial hepatic blood flow, which were correlated with the severity of functional liver disorders regardless of the complication nature. The portal blood flow in the natural course of liver cirrhosis was characterized by 3.5–4.5 times increased volume of visceral blood. Decompensation of the disease was accompanied by a decrease in blood flow in the portal vein as compared to the splenic and superior mesenteric veins by 1.8–2.2 and 1.5–2.7 times, respectively. Arterial blood flow in the natural course of liver cirrhosis was characterized by a relatively increased hepatic arterial flow. The ultrasound criterion of hepatic blood flow “arterialization” was an increase in hepatic-splenic arterial index, which can be used as a sign to differentiate between different forms of portal hypertension. Decompensation of the disease was characterized by an average of 8.2 % decreased arterial blood flow in the hepatic artery compared to the splenic artery in dynamics. Prognostically unfavorable signs were the progression of splenomegaly degree, the increase in the portal vein diameter with the decreased velocity characterizing the increase in congestive index by 2.4–2.6 times, the decrease in the hepatic artery diameter and velocity in it over time.Conclusions. The hepatic and visceral blood flow characteristics should be considered when choosing method of conservative, surgical or minimally invasive treatment of liver cirrhosis complications. Based on the hepatic hemodynamic characteristics, the mismatch between portal perfusion (reduced) and visceral blood flow (increased) is the essence of portal hypertension in liver cirrhosis. Accordingly, the criterion of treatment effectiveness in decompensated liver cirrhosis should be improved portal liver perfusion and (or) reduced volume of visceral blood flow.

Introduction. Due to refinements of assisted reproductive technology, the number of multiple pregnancies has increased substantially. Therefore, transfer of a single embryo, as opposed to multiple embryos, is a top-priority task in ART-based infertility treatment. Time-lapse microscopy (TLM) is a tool for selecting quality embryos for transfer.The aim of the study was to assess the outcomes of single-embryo transfer following embryo incubation in a TLM-equipped incubator in patients undergoing IVF and ICSI.Methods. The study was carried out in 743 infertile women. Single-embryo transfer following incubation in a TLM-equipped incubator was performed in 282 patients, who formed the main group; the control group consisted of 461 patients undergoing singleembryo transfer following a traditional culture and embryo selection procedure. We assessed the quality of transferred embryos, the rates of clinical pregnancy and live birth rates.Results. The groups did not differ in the proportion of IVF and ICSI cycles, terms of age and infertility factors. In the study group, there was a higher proportion of excellent quality embryos for transfer (p = 0.001), a higher proportion of cycles with elective embryo transfer (p = 0.001) and a higher proportion of cycles with cryopreservation of embryos (p

Each type of portal hypertension has clinical and diagnostic peculiarities, which determines the choice of therapeutic approach and subsequently an outcome. Aim. In order to evaluate the arterial blood flow of the liver, which can be ambiguous in the syndrome of portal hypertension, in 85 patients with liver cirrhosis, pre-hepatic and post-hepatic forms of portal hypertension the ratio of arterial blood flow in the hepatic and splenic arteries was studied. Methods and results. To assess the hepatic arterial blood flow, we have introduced a new index – hepato-splenic arterial index, which is determined as the ratio of the flow rates in proper hepatic and splenic arteries. In cirrhosis of the liver, blood flow in the hepatic artery was increased in relation to spleen. With pre-hepatic and post-hepatic forms of portal hypertension which decrease and increase amount of arterial blood in total liver blood flow, respectively, the ratio of arterial blood flow in the hepatic and splenic arteries is unchanged. Conclusion. This suggests that the hepato-splenic arterial index can serve as a differential criterion for determination of causes of portal hypertension syndrome. Portal Hypertension, Doppler Ultrasonography, Liver Cirrhosis

Emergence of renal dysfunction in cirrhosis is an integral part of a natural course of the disease characterizing its weight. In turn, development of renal dysfunction is considered one of the pathogenetic moments of development of the main complications of cirrhosis. Thus principles of diagnostics of renal dysfunction fully are not defined today. Aim. For the purpose of an assessment of diagnostic importance of laboratory criteria violation of secretory function of kidneys in patients with the complicated course of cirrhosis we investigated kidneys function in 120 patients with decompensated cirrhosis depending on positive or negative result of treatment. Methods and results. Laboratory researches included definition of a creatinine, sodium and potassium in blood and urine, glomerular filtration rate (GFR), clearance of an endogenous creatinine and serum cystatin C level. It is established that serum cystatin C level is the most informative criterion of assessment of the renal dysfunction and it can be used as a criterion of efficiency of treatment and prognosis of the clinical course. Conclusion. This indicates the importance of renal dysfunction in development of cirrhosis complications .

Syndrome of portal hypertension in liver cirrhosis is determined pathogenetically by the disparity of reduced hepatic portal perfusion to the increase of flowing blood volume. The role of visceral blood flow, which determines the amount of portal blood, is not valued enough. Aim. The results of survey of 190 patients with liver cirrhosis have been studied in order to assess visceral blood flow. Methods and results. We have analyzed the clinical condition of patients, the ultrasound scan and Doppler ultrasound results, which characterize the blood flow in the portal, splenic and superior mesenteric vein, hepatic, splenic and superior mesenteric arteries. It was found that the splanchnic blood flow in liver cirrhosis is characterized by an increase in volume portal blood. The natural history of cirrhosis of the liver is accompanied by a decrease in portal blood flow relative to splenic and superior mesenteric flow in the transition from compensated to decompensated state. Conclusions. This indicates the decrease in hepatic portal perfusion relative to increase in visceral blood volume, an increase of portal pressure portacaval gradient, being one of the causes of hemodynamic complications.

Early portal hypertension type diagnostics is an ultimate factor concerning kind and tactics of treatment. Aim. To objectify ultrasound examination capabilities, portal hemodynamics were studied in 97 patients using impulse and color doppler. Methods and results. It was ascertained that impulse and color doppler examination allows to visualize portal vein and its branches’ structural abnormalities, define subhepatic and intrahepatic types of portal hypertension, find thrombosis and characterize its stages. In cirrhosis patients with portal hypertension, homogenous doppler signal was received from the portal vessels lumen, while signs of intraluminar pathology were seen in the case of thrombosis of portal vein. Conclusion. This means that ultrasound examination of portal vein and its branches with impulse and color doppler is informative, non invasive method, which helps to define stages of portal hypertension. Doppler ultrasonography doesn’t have negative effect of ionizing radiation and can be used for the repeated research in the dynamics of disease.

Elaboration of the uniform tactical installations concerning questions of diagnostics, rational therapy of patients with sinusoidal dysfunction at cirrhosis and its complications is actual. Aim. For the purpose of assessment of a role of sinusoidal dysfunction at complications of cirrhosis results of 35 patients’ treatment with sinusoidal dysfunction correction were studied. Methods and results. As basis venotonics were used in therapy. The clinical condition of patients, data of ultrasonic dopplerography characterizing the blood flow in vv. porte and lienalis were estimated. It was established that application of venotonics improves portal perfusion and portal vein diameter decrease and linear speed of a blood flow increase. Conclusion. It testifies to the importance of correction of sinusoidal dysfunction and prevention of complications development in patients with cirrhosis.

Aim. Elaboration of the uniform tactical installations concerning questions of rational therapy of patients with renal dysfunction in cirrhosis and its complications is actual. Methods and results. Effectiveness of the treatment of 48 patients with renal dysfunction was studied. As basis therapy terlipressin (Remestip) and albumin were used. It was established that treatment of renal dysfunction improves survival rate of patients and allows to extend terms of complications development. Conclusion. It testifies the influence of correction of renal dysfunction in patients with decompensative course of cirrhosis on duration and quality of their life.