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The choice of steel depends on environmental factors like temperature, pressure, and chemical exposure. Steel components in machinery often face varying conditions that can lead to damage, such as cavitation erosion. In this study, steel 42CrMo4 samples were chosen to represent a common and widely used steel. Application of this type of steel is often related to the statically and dynamically stressed components for vehicles, engines, and machines, where corrosion or cavitation can occur. The behavior of steel samples under conditions of cavitation erosion in distilled water was the focus of this paper. Testing was performed using a standard cavitation vibratory setup using a stationary specimen, according to the ASTM G-32 procedure. Image and morphological analyses were implemented to quantify the level of sample degradation caused by cavitation. The observed changes in the monitored parameters during testing are linked to the degradation mechanism of cavitation erosion. The results showed that pits began forming within 60 minutes, and afterward, the growth and merging of these pits significantly impacted the degradation process.

Engineering materials are often exposed to various extremely harsh surroundings such as high temperatures and/or pressure, thermal shocks, aggressive solutions, or cavitation erosion. The phenomenon of cavitation erosion might be expected in conditions of fluid-flowing where the parts of equipment include turbine blades, high-speed propellers, or pump parts. Such conditions usually cause surface degradation with defects in the form of pits and fractures, resulting in strength deterioration with a potential risk of failure, as well as a reduction in the materials' lifespan that requires additional expenses for failure analysis, repair, and/or replacement of parts. This paper will present the main results regarding the study on cavitation erosion resistance of two different engineering materials, austenitic stainless steel 316L and CuAlNi shape memory alloy (SMA). Cavitation erosion testing was carried out using an ultrasonic vibratory method with a stationary sample. The comparison of the behavior between these two materials in cavitation erosion conditions will be shown based on the results of mass loss and analysis of the pits formed over time. Using image analysis tools, the surface damage levels were quantified. Detailed analyses revealed that CuAlNi shape memory alloy (SMA) exhibited superior in terms of resistance and behavior compared to stainless steel.

Numerous industrial equipment are designed to withstand harsh operating conditions that among others include cavitation erosion. This study examined the cavitation erosion behavior of mullite, a common material used in furnace linings and casting processes such as Lost Foam which is a novel way to produce castings offering both high quality and reasonably priced. The ultrasonic vibratory method with a stationary sample was employed to achieve cavitation erosion, while image analysis was used to measure the degree of surface deterioration. This study aimed to assess the lifetime of mullite under cavitation exposure by quantifying the morphological parameters of the defects through image analysis and by monitoring material behavior. The obtained results were discussed and analyzed in order to understand degradation mechanisms and sample resistance to cavitation erosion. The results demonstrate that mullite is highly resistant to cavitation, as the volume loss is minimal and the surface degradation is below 6% after 180 minutes of exposure.

Many steels are used in specific environments, while one of these is maritime applications. High-strength 42CrMo4 steel finds numerous applications in the marine industry, including shaft parts, crankshafts, connecting rods, drilling joints, pump parts, steam turbines, and salvage equipment. In order to provide performance reliability in the marine environment, it is essential to study the corrosion resistance of surfaces of 42CrMo4 steel components and parts. The steel's behavior is typically evaluated in a synthetic NaCl solution, which is prepared as a standard substitute for seawater. This paper is focused on the behavior of the steel samples under corrosion conditions in NaCl solution. The level of sample surface degradation which is caused by the corrosion over a 4-month exposure period was evaluated using SEM/EDS analysis. The mass loss increased during the testing period, following an almost linear model in all time periods.

Background: The First Dorsal Metacarpal Artery (FDMA) Flap or Foucher’s flap is an island pedicle flap proximally based on the first dorsal metacarpal artery and veins. A branch of radial sensory nerve is incorporated in the flap to make it a sensate flap. Objective: The aim of our study was to evaluate the functional and aesthetic outcomes of the seven FDMA flaps done over a period of four years for reconstruction of the distal thumb soft tissue defects and one defect over proximal phalanx of the index finger. Methods: This prospective study was performed between 2018 and 2022 at the Clinic of Reconstructive and Plastic Surgery. We present a series of six cases of distal thumb soft tissue defects and one patient with defect over the dorsal aspect of the index finger that were reconstructed with the FDMA flap. Results: In six patient donor site was grafted by full-thickness skin graft harvested from the groin and in one case was closed primary. All flaps survived and one case that was closed primary had donor site complication that was related to primary closure of the skin. All the patients had good fine touch and average two-point discrimination of 8.7 mm. Conclusion: FDMA flap is a useful and reliable flap to cover the defects of the dorsal aspect and to a certain extent the volar aspect of the thumb. We showed that can be used to cover the defects over proximal phalanx of the index finger. The flap provides adequate soft tissue coverage and good aesthetic results.

Corrugated cardboard finds extensive use in the packaging industry due to its performance characteristics. It is a lightweight material with excellent mechanical properties, easy recyclability, and environmental friendliness, making it the preferred choice. While numerous studies have investigated the effects of external factors on corrugated cardboard and its mechanical properties using simulation modeling, there is a lack of research focusing on simulating and predicting the construction of corrugated cardboard itself. The shape and size of the corrugated medium significantly impact the performance of corrugated cardboard. However, strict standards for the parameters of the medium's size and shape to achieve optimal elasticity and strength are lacking. Therefore, this study aims to explore the modification of the design of one component of corrugated cardboard to enhance its performance

Introduction: Treatment-resistant hypertension (TRH) is a frequent phenomenon, for which no complete solution has yet been found. More than 5% of patients treated for hypertension do not achieve blood pressure control with three first-generation antihypertensive drugs. Objective: The aim of this new cohort investigation, which is an extension of the TRYCORT study, is to re-examine the efficacy and safety of additional antihypertensive therapy in a group of adult patients with TRH. Methods: The study was designed as multi-national, multi-centre, prospective cohort study, which compared effectiveness and safety of add-on treatmentsof resistant hypertension. The patients were followed-up for 6 months, and primary outcome was treatment response. Results: In total139 patients completed the study(66women and 73 men), with average age of 63.6 years. Initial add-on therapy was changed at study visits if response to treatment was inadequate. The blood pressure below 140/90 mmHg was achieved in 75% of patients with add-on spironolactone, while effectively all patients achieved drop in systolic blood pressure ≥ 10 mmHg, and drop in diastolic blood pressure ≥ 5 mmHg. Only one treatment-related adverse effect was observed (pretibial oedema in patient taking amlodipine), while serum levels of potassium remaind within the reference limits. Quality of life increased and paralleled the treatment response. Conclusion: In conclusion, spironolactone proved to be the most effective and safe add-on therapy of resistant hypertension, but it needs several months of regular intake to achieve full effect and improve quality of life. Conclusion Spironolactone proved to be the most effective and safe add-on therapy of resistant hypertension, but it needs several months of regular intake to achieve the full effect and improve quality of life.

Rural tourism is gaining popularity due to a healthier stay in a less developed rural environment. Sarajevo Canton, Bosnia and Herzegovina’s most popular destination strives to enhance its tourism offer by developing rural tourism in its immediate surroundings. The “green ring,” a basin rim with preserved forest ecosystems and rural villages, serves as the foundation for the rural tourism product. The paper analyses the characteristics of rural tourism in the vicinity of Sarajevo and the role of stakeholders in planning rural tourism. Fieldwork, surveys, and interviews with tourism industry representatives were conducted to determine the cohesion of joint activity and the key features of rural tourism development. Domestic tourists make up the majority of rural visitors, although tourists from the Middle East and Europe are particularly interested in rural tourism. The top motives for visiting rural areas are walking and hiking, traditional gastronomy, and escaping from everyday life. The paper clarifies the challenges and barriers to rural tourism development.

This paper investigates the impact of explanatory variables that determine the financial stability of the banking sector in Bosnia and Herzegovina, and the possibility of controlling credit risk, which is a threat to the stability of the financial system for the period from 2009 to 2019 on a quarterly basis. Correlation and panel regression analysis are also applied in this paper. The selected independent (explanatory) variables are the growth rate of savings of the household sector, the growth rate of foreign direct investments, the growth rate of exports, the growth rate of total loans, the growth rate of non-per- forming loans, the growth rate of capital adequacy ratio, and unemployment growth rate. The GDP growth rate will be used as the dependent variable. The research results showed that the most significant impact on the GDP growth rate was recorded by the following variables: the growth rate of foreign direct investment, the growth rate of exports and the growth rate of total loans. On the other hand, the following variable recorded the most significant negative impact: the growth rate of the household sector. The study also shows that there is a positive causal relationship between the growth rate of non-performing loans and the growth rate of unemployment.