On weighted estimates for the stream function of axially symmetric solutions to the Navier-Stokes equations in a bounded cylinder

Higher-order estimates in weighted Sobolev spaces for solutions to a singular elliptic equation for the stream function in an axially symmetric cylinder are provided. These estimates are essential for investigating the existence of axially symmetric solutions to incompressible Navier-Stokes equations in axially symmetric cylinders. To derive the estimates the technique of Kondratiev is incorporated. The weight has a form of a power function of the distance to the axis of symmetry

24-satna aktivnost gorskog puha (Dryomys nitedula)

Five forest dormice (Dryomys nitedula Pallas, 1778) were studied in cage conditions. The level of activity was measured in terms of the percentage of time spent by an animal out of the nest, with 24-hour period taken as 100%. Air temperatures were measured in the course of the research. The dormice were shown to be mainly active at night, though with limited daytime activity. The close relationship between level of activity and mean 24-hour temperature was established.Five forest dormice (Dryomys nitedula Pallas, 1778) were studied in cage conditions. The level of activity was measured in terms of the percentage of time spent by an animal out of the nest, with 24-hour period taken as 100%. Air temperatures were measured in the course of the research. The dormice were shown to be mainly active at night, though with limited daytime activity. The close relationship between level of activity and mean 24-hour temperature was established

Minimum query set for decision tree construction

A new two-stage method for the construction of a decision tree is developed. The first stage is based on the definition of a minimum query set, which is the smallest set of attribute-value pairs for which any two objects can be distinguished. To obtain this set, an appropriate linear programming model is proposed. The queries from this set are building blocks of the second stage in which we try to find an optimal decision tree using a genetic algorithm. In a series of experiments, we show that for some databases, our approach should be considered as an alternative method to classical ones (CART, C4.5) and other heuristic approaches in terms of classification quality

Feasibility and accuracy of new insertion technique of S1 transpedicular screw. Computed tomography-based morphometric analysis

Objective To assess feasibility and accuracy of a new insertion technique of S1 transpedicular screw. Summary of background data Transpedicular stabilization in the first sacral vertebra (S1) is a technically demanding surgical procedure with inherent risk of loosening of the implant. A modification of the technique was recently proposed, along with the analytical verification which was performed based on the available literature. In the study, we performed radiological assessment of screws inserted into the S1 using the classical and modified techniques. Methods The analysis was performed in two parts. The first part was performed on eight cadaver specimens after implantation of the screws. In the second part, we used computed tomography images of patients with degenerative disk disease with a superimposed representation of screws. The thickness of the posterior cortex adherent to the screws, screw trajectory and their position with regard to the spinal canal was measured. The area of posterior cortex in contact with the screws was also calculated. Results The contact length and area was found to be two times greater for screws introduced with the modified technique. The convergence angle was comparable between the techniques, despite the shift of entry point. There was no canal breach, although with the modified technique the screws passed closer to the spinal canal. Conclusions The modified technique is considered safe. In this technique, the screws pass through a thicker portion of the posterior cortex compared to the classical technique that aims at improving the stability of the fixation

Prospective multicentre study of carotid artery stenting using the MER™ Stent : the OCEANUS study : 30-day and one-year follow-up results

Introduction: Constant technological progress in the field of carotid stenting translates into improved short- and long-term results of endovascular treatment. The introduction of a new generation, self-expanding, open-cell stent has provided a new treatment option in endovascular management of carotid stenosis. Aim: To evaluate 30-day and 1-year clinical outcomes of non-consecutive patients with high risk of carotid endarterectomy, who underwent 5F cylinder-tapered MER™ open-cell carotid stent implantation. Material and methods: It was a single-arm, prospective study conducted in four experienced catheterisation centres. The use of embolic protection devices was mandatory. The primary endpoint was stroke in 30-day follow-up. The secondary endpoints were 30- day and 1-year cumulative incidence of death, stroke and myocardial infarction, 1-year target vessel revascularisation, procedural success (residual stenosis ≤ 30%), restenosis rate (%DS ≥ 50%), and Serious Adverse Device Effect (SADE) rate in 1-year follow-up. Results: In total 100 patients were recruited for the study, with the majority being males (n = 61). The mean age was 68.3 ±8.2 years, and most of the patients were asymptomatic (n = 56). In 55 (55%) patients direct stenting was performed, with the use of proximal protection devices in 19 (19%) patients. Mean internal carotid artery/common carotid artery stenosis before and after stent implantation was 81.98 ±9.15% and 12.52 ±8.70%, respectively (p < 0.001). Procedural success was achieved in all cases. One ischaemic stroke was observed at 30 days (1%, primary endpoint). At 1-year follow-up two myocardial infarctions and three deaths occurred with no additional stroke. Conclusions: The OCEANUS study indicated the safety and efficacy of the MER™ stent during 30-day and 1-year follow-up in both symptomatic and asymptomatic patients. The majority of patients were event-free. However, larger cohort studies are needed to evaluate MER™ stents in detail

Plasma total antioxidant status in breast cancer women in relation to lymph node involvement and HER-2/neu expression

BackgroundOxidants can act at several stages of malignant transformation. To protect against toxic effects of oxidants and to modulate physiological effects of their action organisms have developed antioxidant defence systems. Plasma total antioxidant activity (TAS) measures peroxyl-scavenging capacity of the extracellular antioxidant system.AimThe goal of this pilot study was to evaluate the plasma total antioxidant status in breast cancer women in relation to lymph node metastases and HER-2/neu expression.Materials/MethodsNewly diagnosed consecutive breast cancer patients (n=26) were recruited before any treatment and matched with controls (n=24) randomly selected from benign breast disease patients. Cancer progress was established according to lymph node involvement: No or N+. HER-2/neu was considered as either negative (0 or 1+) or positive (2+ or 3+). The plasma total antioxidant status (TAS) was measured by colorimetric test (RANDOX). HER-2/neu oncogene expression was determined in breast cancer tissue using the immunohistochemical method (Hercep Test).ResultsThe study demonstrated a significant decrease in the mean TAS level (mmol/L) in the breast cancer group (1.42±0.22) in comparison to the control group (1.56±0.18;

In pursuit of COVID-19 surgical risk stratification to manage a limited workforce and supplies in minimally invasive surgery

The protective barriers used so far in surgery do not provide adequate protection against SARS-CoV-2 virus, and reinforced protective equipment is needed. The rapid increase in the number of patients and the worldwide panic associated with the increasingly low availability of protective equipment has resulted in a shortage of protective equipment In many hospitals. Appropriatepersonal protective equipment must be provided so that the surgical team proceeding to surgery is not excluded from the further struggle for patients’ health, especially in MIS. Reckless and excessive use of maximum protective equipment may result in a severe shortage of these products when the number of infected person