Futures of Civil Aviation Operations explored from the perspective of Finnair

Civil aviation is one of the busiest transport sectors which to this day has no competitors when it comes to speed and efficiency of transporting passengers and goods all around the world. Because of this the industry is constantly developing and trying to meet the huge demand for its services. The world economy directly depends on its main carrier, without which world trade would not be carried out in such large volumes and at such a fast pace. However, the function of civil aviation is totally dependable on various factors that directly or indirectly affect it. If we were only to look at the biggest pieces of the puzzle, such as the economy, politics and environmental changes, it could be easier to predict the future direction of civil aviation. However, we are left flustered when critical events, the so-called wild cards such as the COVID- 19 pandemic, occur. Such events have already proved to us that they can in the worst case scenario completely suspend civil aviation operations and lead to the stagnation of global economy. The purpose of this study is to go beyond the obvious and to identify some of the most important underlying factors which are likely to affect the future of aviation in the next twenty years. The aviation industry goes tightly together with the forefront of technology and is in the middle of search for innovations that can help achieve a more sustainable world where civil aviation still exists. Climate change is forcing the aviation industry, among many other fields, to look for solutions to drastically cut their carbon emissions while subsequently more and more consumers are choosing to minimize their carbon footprint and avoid air travel. Moreover, climate change is not the only struggle aviation has to face in the future. The war in Ukraine has showed us how much of an inconvenience wars and military operations can be for civil aviation with plane routes being re-directed to avoid war-zones adding thousands of miles into their journey. Likewise the safety of civil aviation is always at risk when military actions including missiles are carried out, and even outside of war the industry still has not reached a 100% flight safety despite the extensive efforts of building safer and more reliable aircrafts. In addition, the industry which once was the crown jewel of human innovation is having to face the harsh reality that modern artificial intelligence might one day take over some of the key elements of aviation including piloting the planes. These among other factors will most likely affect civil aviation in the next 20 years. The images of the future presented in this study and identified as critical are based directly on these scenarios and are backed up by information obtained from suitable sources on this topic

Management of hepatocellular carcinoma: a study on 240 patients in a single referral center

Epidemiology of hepatocellular carcinoma (HCC) is changing globally and trends show an increasing morbidity rates in Northern, Cen­tral and Eastern Europe and North America but a slow decline in Japan, Korea and China. The bur­den of this important complication of chronic advanced liver disease will further increase in the next 10 years. Several reviews focus on a broad spectrum of HCC clinical manage­ment worldwide, including surveillance of patients with cirrhosis thus establishing proper HCC diagnostic and therapeutic options.The study of I. Ivanova et al. involves patient data from a single referral center in St. Marina University Hospital of Varna. It is the first report of the results of a project enti­tled ‘Hepatocellular Carcinoma - a Current Diagnos­tic and Therapeutic Approach`. The study achieves its goal to present the results from this multidisciplinary HCC treatment.This is one of the three largest cohort studies in Bulgaria so far. The paper reports 240 HCC patients during an 11-year period (from 2006 to 2016) in the Clinic of Gastroenterology, St. Marina University Hospital of Varna. These results aim at evaluating the risk factors for HCC and etiology of chron­ic liver disease, the characteristics and severity of underlying liver disease, the methods for HCC diagnosis and tumor burden as well as staging and treatment methods.The analysis of the risk factors for HCC and etiology of chron­ic liver disease shows that chronic hepatitis-B virus (HBV) infection has been registered in 40.4% and chronic hepatitis-C virus (HCV) infection - in 25.8% of HCC patients. There are two cases with HBV/HCV co-infection and four had HBV/hepatitis-D virus (HDV) co-infection. The other rare etiologic factors for chronic liver disease in our cohort are the following: Wilson`s disease in three, autoimmune hepatitis - in two and non-alco­holic fatty liver disease (NAFLD) - in one patient. Unknown etiology has been registered in 28 patients, as 10 of them (36%) have presented with a marker for exposure to HBV (anti-HBc positive antibodies). Despite the common understanding of the link between liver cirrhosis and HCC, only 82% of HCC patients have developed this pathology. HCC is the first complication of chronic liver dis­ease in 2/3 of cases (n=156). One limitation of the study when comparing laboratory results is the lack of similar cohort of patients without malignant transformation.The diagnostic algorithm includes various imaging and biopsy modalities. The primary diagnosis of HCC is based on at least two imaging methods in 133 cases. In any other patients, the imaging method is combined with at least one ultasonography- or computed-tomography-guided biopsy of the he­patic lesions. The pa­tients with very early and early HCC stage account­ for 13% of all HCCs.The treatment modalities encompass every current modality available such as surgical resection (in 23%), radiofrequency ablation (in 5%) and transarterial chemoembolization (TACE) (in 2% of the cases). System­ic therapy, predominantly with Sorafenib, has been intro­duced to 17% of the patients.The significance of ultrasound surveillance in liver cirrhosis patients is confirmed with the large percentage of diagnosed tumors - 51%. In contrast, most HCCs are detected at stage D, mainly due to advance baseline liver cirrhosis.In summary, findings from this study confirm that surveillance with ultrasound and tumor markers like alpha-fetoprotein (AFP) among pa­tients with advanced liver disease may increase HCC detection rate and achieve longer patient survival rate

Surgery at daybreak of the new millennium: traditions and innovations

In recent years, colorectal surgery faces a series of challenges associated with the interdisciplinary ap­proach in the biomedicine and clinical medicine of the new millennium. The Department of General and Op­erative Surgery at the Medical University `Professor Paraskev Stoyanov` of Varna has already organized 14 national conferences of coloproctology with rising international participation. The present jubilee Fifteenth International Congress of Colorectal Surgery represents the continuation of these conferences of coloproctol­ogy. It preserves the best practices and traditions and, in the same time, it traces the pathway to new innova­tions and scientific advances in this field of increasing socio-medical importance worldwide. It should be em­phasized that these traditional conferences have substantially contributed to mutual exchange of experience and methodology as well as of theoretical and practical achievements between scientists and practitioners. It has considerably extended the interpersonal contacts and fruitful interrelations within the medical class and with the public as well

Applications of Monte Carlo Simulation in Modelling of Biochemical Processes

The biochemical models describing complex and dynamic metabolic systems are typically multi-parametric and non-linear, thus the identification of their parameters requires nonlinear regression analysis of the experimental data. The stochastic nature of the experimental samples poses the necessity to estimate not only the values fitting best to the model, but also the distribution of the parameters, and to test statistical hypotheses about the values of these parameters. In such situations the application of analytical models for parameter distributions is totally inappropriate because their assumptions are not applicable for intrinsically non-linear regressions. That is why, Monte Carlo simulations are a powerful tool to model biochemical processes

Peritoneal metastases in colorectal cancer

Peritoneal carcinomatosis (PC) is a common evolution of cancer of the gastrointestinal tract, and has been traditionally regarded as a terminal disease with short median survival. During the last 20 years, due to its favourable oncologic results, a new loco-regional therapeutic approach, combining cytoreductive surgery with intra-operative intraperitoneal chemotherapy has achieved an important development. After liver metastatic disease, peritoneal carcinomatosis is the second most frequent cause of death in colorectal cancer patient is defined as a stage IV tumour which prognosis is the worst. The extent of peritoneal carcinomatosis is, however, difficult for assessment preoperatively, and precise evaluation is most often performed during surgical exploration. Cytoreductive surgery associated with chemotherapy for the treatment of peritoneal carcinomatosis should be performed in young patients with limited and resectable carcinomatosis, in specialized institutions involved in the management of peritoneal surface malignancies

Surgical treatment of patients with chronic constipation - experience of Clinic of Coloproctology - Varna

BACKGROUND: Patients with chronic constipation can be difficult to manage either medically or surgically. We used Roma classification as criteria for including patients in our study. There are many diseases which could lead to chronic constipation. If they are treated by a surgeon, there can be obtained a permanent therapeutic effect. The group of patients with idiopathic chronic constipation couldn't obtain satisfying effect by surgical treatment, which was presided by inaccurate and embarrassed selection. Our aim is to present the results of experience of Clinic of General and Operative Surgery, Varna, Bulgaria.MATERIAL: For a period of 10 years, we have been operated 52 patients with diagnosis as morbus Pair (15 patients), megacolon (31 patients), and idiopathic chronic constipation (6 patients). The main indication for undergoing surgical treatment was the retention of more then 20% of the applied barium enema after the 5th day from irrigography. There were applied the followed operative methods: colectomy, subtotal colectomy, hemicolectomy, resection of the colon sygmoideum, anterior resection of the rectum and mobilization of the lineal flexure. We did analysis of the results. The evaluation of curativeness to applied methods was done. We followed the quality of life of our patients from 11 months to 6.2 years (median 3.2 years).CONCLUSION: The presence of organic disease is associated with very good therapeutic effect from the surgical treatment of chronic constipation. The problem with idiopathic chronic constipation remains unsolved when colectomy with ileo-recto anastomosis was undergone. The right selection of patients is a crucial factor for the success of the surgical treatment

CALCULATION OF LOSSES OF ACTIVE POWER AND ENERGY IN TRANSMISSION LINES AND TRANSFORMERS, AS A PART OF THE ELECTRICAL DISTRIBUTION POWER NETWORK

The paper inhere discusses the impact of renewable distributed generation sources upon the power and energy losses in electrical distribution power networks where these sources are attached. In addition a set of mathematical expressions to calculate these active power and energy losses are presented with the respective examples and implementation

Comparative analysis of application of conventional colonoscopy and NBI colonoscopy for detection of early colorectal cancer

PURPOSE: Extending life expectancy is one of the major causes for increasing cancer incidence rate. The objective of the present investigation is to compare the diagnostic value of conventional and narrow band imaging (NBI) colonoscopy for the early diagnosis of colorectal cancer.MATERIAL AND METHODS: We examined 163 patients hospitalized in the First Clinic of Surgery, St. Marina University Hospital of Varna, for a period from 2010 to 2012 and compared the diagnostic modalities of conventional colonoscopy and NBI-colonoscopy.RESULTS: NBI colonoscopy with magnifying endoscopy had the potential to detect more lesions remaining not identified by conventional endoscopy. The relative share of newly-increased mucosal changes increased by 1.9 times (52%). The newly-diagnosed lesions were mostly small sized. We diagnosed by 2.7 times more lesions sized less than one mm as well as by two times, 1.7 and 1.3 times more lesions sized 1-3 mm, 3-5 mm and 5-9 mm, respectively. The method did not establish any new formations larger than one cm or more. The main part of the newly-detected lesions presented with non-specific inflammatory changes, i.e. by 9.2 times more often when compared to conventional endoscopy and represented hyperplastic/ inflammatory polyps by 2-3 times more often. In four new lesions there were either an early cancer, or areas of high-grade dysplasia while in 12 ones there was a low-grade dysplasia.CONCLUSION: NBI colonoscopy with magnifying endoscopy represents a reliable method for the diagnosis of small neoplasms of the colon.Scripta Scientifica Medica 2013; 45(2): 43-47