SEMANTIC APPROACH TO SMART CONTRACT VERIFICATION

Vulnerabilities of smart contract are certainly one of the limiting factors for wider adoption of blockchain technology. Smart contracts written in Solidity language are considered due to common adoption of the Ethereum blockchain platform. Despite its popularity, the semantics of the language is not completely documented and relies on implicit mechanisms not publicly available and as such vulnerable to possible attacks. In addition, creating formal semantics for the higher-level language provides support to verification mechanisms. In this paper, a novel approach to smart contact verification is presented that uses ontologies in order to leverage semantic annotations of the smart contract source code combined with semantic representation of domain-specific aspects. The following aspects of smart contracts, apart from source code are taken into consideration for verification: business logic, domain knowledge, run-time state changes and expert knowledge about vulnerabilities. Main advantages of the proposed verification approach are platform independence and extendability

An increase of hydro-aggregate's installed power and efficiency factor before the revitalization phase

The revitalization of hydro-aggregates should be performed before the life-time expiry of most their parts. But, as in our practice aggregates have been under exploitation much longer then theoretical life-time advices (40, even 50 years), there is a need to estimate the equipment's condition through more sophisticated monitoring, providing the maximum level of safety and availability with minimum investment expenses, before the revitalization finally takes place. That estimation is based on appropriating calculations and measurements needed to take the competent decision. Results of that analysis can be also useful for estimation of the aggregate's power and parameters after the revitalization. In this paper the results of appropriate calculations and measurements for the Hydropower station HE Zvornik are given

An increase of hydro-aggregate's installed power and efficiency factor before the revitalization phase

The revitalization of hydro-aggregates should be performed before the life-time expiry of most their parts. But, as in our practice aggregates have been under exploitation much longer then theoretical life-time advices (40, even 50 years), there is a need to estimate the equipment's condition through more sophisticated monitoring, providing the maximum level of safety and availability with minimum investment expenses, before the revitalization finally takes place. That estimation is based on appropriating calculations and measurements needed to take the competent decision. Results of that analysis can be also useful for estimation of the aggregate's power and parameters after the revitalization. In this paper the results of appropriate calculations and measurements for the Hydropower station HE Zvornik are given

Evolution of cataract surgery: Smaller incision - less complications

Background/Aim. Cataract surgery has become one of the safest procedures in medicine thanks to advances in technology and surgical techniques. Although minimal, we still witness different complications. The aim of this study was to compare visual outcome and complication rate in different techniques of cataract surgery, ie in cataract surgeries with various corneal incision width. Methods. The study included 3,457 consecutive patients, ie 4,670 eyes that had undergone cataract surgery. The used surgical techniques were: extracapsular cataract extraction, phacoemulsification/ forceps IOL implantation, phacoemulsification/ injector IOL implantation, microincision cataract surgery (MICS). Patient follow up was 6 months. Patients were evaluated for: visual aquity, corneal astigmatism, cellular reaction in the anterior chamber, IOL position. Results. Uncorrected visual aquity 30 days postoperatively was ≥ 0.5 in 30% of the eyes - ECCE; 54.7% of the eyes - phacoemulsification/forceps IOL implantation; 63.0% of the eyes - phacoemulsification/injector IOL implantation; 5/8 of the eyes - MICS. Endophthalmitis was detected in 0.15% of the eyes - ECCE and 0.1% of the eyes - phacoemulsification/forceps IOL implantation. In eyes with phacoemulsification/injector IOL implantation or microincision cataract surgery (MICS) there were no cases of endophthalmitis. After a 6-month period intraocular lens were dislocated in 7.2% of the eyes - ECCE, and 0.6% of the eyes - phacoemulsification/PMMA IOL. There was no IOL dislocation in other surgical techniques. Conclusion. Shorter corneal incision implies less complications, less operative trauma, faster visual rehabilitation and better visual outcome

14 C-urea breath test in the detection of Helicobacter pylori infection

Helicobacter pylori infection is supposed to be one of the major causes of digestive and other diseases. Among a lot of invasive and non-invasive methods for its detection, none is ideal. The aim is an assessment of the Helicobacter pylori infection in the stomach using breath test and comparison to other diagnostic methods, as well as following up the effects of therapy. In 17 patients with digestive discomfort, breath test, rapid ure- ase test and histology were performed, while in 47 patients with proven HP infection the effect of therapy was followed up using breath test and clinical findings. Breath test was performed af- ter per oral administration of the capsule of 14 C urea (37 kBq). Findings of the breath and urease tests were in accordance in 14/ /17 patients (83%) while breath test and histology in 16/17 patients (94%). During follow-up of the therapeutic effects, breath test and clinical findings were in accordance in 43/47 patients (98%). Breath test can be useful in diagnosis but is a method of choice in following up the patients after therapy for H. pylori infection, because it is non-invasive, fast and precise

Gastrointestinal symptomatology as first manifestation of systemic erythematous lupus

Background. Systemic lupus erithematodes (SLE) is chronic, often febrile, multisystemic disease unknown origin and relapsing course which affects connective tissue of the skin, joints, kidney and serous membranes. Gastrointestinal manifestations are rarely the first sign of systemic lupus erythematosus. Case report. We presented a female patient, 35 years old, whose first symptoms of SLE were paralitic ileus (chronic intestinal pseudo-obstruction) and polyserositis (pleural effusion and ascites). Except for high parameters of inflammation, leucopenia and thrombocytopenia, all immunological and laboratory tests for SLE were negative in the onset of the disease. During next six months the patient had clinical signs of paralitic ileus several times and was twice operated with progressive malabsorptive syndrome. The full picture of SLE was manifested seven months later associated with lupus nephritis. Treatment with cyclophosphamide, corticosteroids and total parenteral nutrition (30 days) induced stable remission of the disease. Conclusion. The SLE can be initially manifested with gastroenterological symptoms without any other clinical and immunologic parameters of the disease. If in patients with SLE and gastrointestinal tract involvement malabsorption syndrom is developed, a treatment success depends on both immunosupressive therapy and total parenteral nutrition

The association of early postoperative lactate levels with morbidity after elective major abdominal surgery

Lactate levels are widely used as an indicator of outcome in critically ill patients. We investigated the prognostic value of postoperative lactate levels for postoperative complications (POCs), mortality and length of hospital stay after elective major abdominal surgery. A total of 195 patients were prospectively evaluated. Lactate levels were assessed on admission to the intensive care unit (ICU) [L-0], at 4 hours (L-4), 12 hours (L-12), and 24 hours (L-24) after the operation. Demographic and perioperative clinical data were collected. Patients were monitored for complications until discharge or death. Receiver operating characteristic (ROC) curves were used to determine the predictive value of lactate levels for postoperative outcomes. The best cut-off lactate values were calculated to differentiate between patients with and without complications, and outcomes in patients with lactate levels above and below the cut-off thresholds were compared. Univariate and multivariate analyses were used to identify variables associated with POCs and mortality. Seventy-six patients developed 184 complications (18 deaths), while 119 had no complications. Serum lactate levels were higher in patients with complications at all time points compared to those without complications (p lt 0.001). L-12 had the highest predictive value for complications (AUROC(12) = 0.787; 95% CI: 0.719-0.854; p lt 0.001) and mortality (AUROC(12) = 0.872; 95% CI: 0.794-0.950;p lt 0.00l). The best L-12 cut-off value for complications and mortality was 1.35 mmol/l and 1.85 mmol/l, respectively. Multivariate analysis revealed that L-1(2) >= 1.35 mml/l was an independent predictor of postoperative morbidity (OR 2.58; 95% CI 1.27-5.24,p = 0.001) . L-24 was predictive of POCs after major abdominal surgery. L-12 had the best power to discriminate between patients with and without POCs and was associated with a longer hospital stay

MULTI CRITERIA OPTIMIZATION OF LOW-RISE DETACHED HOUSE HEATING SYSTEMS IN AN ATTEMPT TO MINIMIZE ENVIRONMENTAL DAMAGE AND MAXIMIZE COMFORT OF USE

This paper analyzes the process of multicriteria optimization in Design Builder software. The analysis is oriented on the process of achieving, analyzing choice of an optimal solution for the specific case of a low-rise detached house project. Presented are, the criteria for optimization and used parameters. This research verifies the assumption that it is possible to minimize price, damaging effects on the environment and discomfort in housing units, which is proven by the results of this research.Publishe