Volume 5 (2022): Issue 1 (April 2022)

Recently, there has been an increase in the growth and advancement of electric propulsion in marine electrical drives. A maximum amount of energy is utilized by ships for propulsion drives. To be aware of it and develop an optimized structure to improve the effectiveness of the propulsion system with power consumption is necessary. The proposed paper aims to develop a model and perform functional analysis as per the above understanding and requirements. The factors considered include greenhouse gas emissions, CO2 emissions, environmental aspects, and the availability of non-renewable resources, which leads to the introduction of renewable energy as a replacement method of power generation. For this work, two different renewable sources, such as solar and wind energy, were chosen. The combination of these two resources can manipulate the voltage and satisfy the load in a desirable way. For voltage improvement, a high gain converter with a minimal number of active and passive components is selected. This system adopts a storage system to meet the needs in the future. The inverter switches are controlled by the recommended control algorithm, which can balance and provide adequate power towards the drive by a feedback control loop. The speed of propulsion in the drive is adjusted by the induction motor coupled with the propeller. The analytical study of the proposed system is carried out in MATLAB software. The simulation study revealed the effectiveness of this modern optimization technique.

This paper presents the analysis of the natural convection process that takes place near a vertical plane wall embedded in a constant temperature and linearly mass stratified fluid (the Prandtl number and the Smith number are smaller than 1.0, while the Lewis number is greater than 1.0). The wall has a constant temperature, while the flux of a certain constituent is constant at this boundary. The scale analysis and the finite differences method are used as techniques of work. The scale analysis proves the existence, at equilibrium, of heat and/or mass driven convection regimes along the wall. The finite differences method is used solve the governing equations and to verify the scale analysis results using two particular parameters sets.

Green algae biomass represents an important natural resource found in marine environments which could offer new applications in the pharmaceutical and cosmeceutical industries. The paper aim was to characterize some fluid extracts of Ulva lactuca L. green macroalgae species, in the Ulvaceae family, from Romanian Black Sea Coast, through physical, chemical and biological methods. For biomedical applications it is important to study how the difference between the marine environment specific conditions, from which they are harvested, can influence the chemical composition of macroalgae. Another important aspect which could affect the bioactive green macroalgae extracts composition, is the influence of applied extraction method. In this way, the less distructive cold maceration method in different solvent concentrations was chosen, according with literature data. The extracts have been studied in order to determine total polyphenols content, total antioxidant capacity by photochemiluminescence method and antibacterial activity. The results emphasized an antioxidant and antibacterial activity of the studied macroalgae extracts, which can be improved in mixture with other bioactive natural substances, in order to obtain new pharmaceutical preparations for topical applications. The valuable obtained results offer the possibility to propose this natural resource for next studies as biomaterial in tissue engineering, wound dressing and drug delivery systems. We consider that Ulva lactuca L. green macroalgae species of Romanian Black Sea Coast, could be an important source of marine bioactive compounds with various uses in the biomedical field.

Ganoderma lucidum is a well-known medicinal mushroom with a long history, used as an ancient remedy for promoting health and increasing longevity. This species of Ganoderma genus is important for our study because it has an interesting chemical composition and pharmacological benefits such as immune suppressor, hypocholesterolaemia, hypotensive, antitumoral, antioxidant, anti-inflammatory agents, and more others. G. lucidum chemical composition has many compounds such as vitamins (mainly Vitamin E), polysaccharides, triterpenes and each one of them is offering a distinctive pharmacological effect. This species of Ganoderma medicinal mushroom is used extensively for its internal effect on improving immune system, hepatoprotective benefit and additionally, a large variety of people consume Ganoderma lucidum as tea infusion and coffee because its antioxidant and reducing stress effects.

Rhizostoma pulmo is a jellyfish from the Black Sea basin that can be a source of natural bioactive compounds with substantial beneficial implications. It is important to use under-exploited marine resources in areas such as pharmaceuticals industry, medicine, cosmetics and dermatology. Marine collagen can be obtained from various sources. Several studies have focused on marine collagen, namely its extraction from alternative sources: fish, invertebrate marine animals such as sea sponges or jellyfish. The novelty is the extraction of marine collagen obtained from jellyfish of the species Rhizostoma pulmo found in the Black Sea and along the coast, the physico-chemical characterization, comparison with other types of collagenic extracts from fish and finally the formulation of a pharmaceutical preparation with medical applications.

The outbreak of covid-19 is having a significant impact on both the physical and social environment. Over 108.2 million people still uncounted (1). Among the sectors of a hospital, the emergency service is one of the most challenging in relation to the promotion of care quality. Achieve good levels of satisfaction of patients of these services is a difficult task (2) due to weaknesses caused by overcrowding, lack of hospital beds, lack of human resources and inadequate physical infrastructure to meet all demand (3). The difficult situation created, during the pandemic outbreak, focused the entire influx of patients, in the emergency service, which encountered the initial difficulties, of facing a completely unknown and unimaginable crisis, deepening the above problems. Patient satisfaction, as a perception and an attitude that a consumer can have or view towards a total experience of health care, is a multidimensional aspect, which represents a vital key marker for the quality of health care delivery (4). The purpose of this study is to assess patient’s satisfaction with the emergency service in the regional hospital of Durres, during Covid-19 pandemic period, as well as to identify the main problems that led to patient’s dissatisfaction with the quality of service. In a for month period, 200 patients who received services at this hospital while affected by covid-19, were interviewed. A structured questionnaire was used to collect data from participants. The collected data were processed by SPSS statistical software. The main result of the analysis, showed that 62% of the respondents were satisfied with the service received, and that the degree of dissatisfactions on the rest of the patients was mainly related to the large number of patients hospitalized ate the same time, which created uncertainty among patients, about the service received and the fear to neglect. Preparing staff to deal with such critical situations is a must, as a good proportion of patients often perceived the insecurity of physicians and nurses in providing first aid. The overall opinions about the satisfaction level of patients for the availability and empathy of doctors in the hospital were good. As a conclusion we can say that there is a strong positive relationship between patients satisfaction and the promptness in the service as well as the necessary spaces for the treatment of patients.

Recently in science, seaweeds are widely used because of their relevant compounds and potential origin of antimicrobial, antiviral and antioxidant activity. Seaweeds are rich in the trace elements and essential minerals that are hard to find in terrestrial plants. Ceramium rubrum is one of the red seaweeds that can be found in the Black Sea on the Romanian coast that has not been enough studied for their bioactive compounds. Identification and quantification of the biomolecules is carried out by specific methods. The compounds that have been found are cumarines, sterols, flavonoic aglicoles, triterpenes and polysaccharides. Is well known that this kind of biomolecules are very important in the pharmaceutical industry. Ozes and poliozes, reducing compounds and catehic tanin we’re also identified from the red algae.

Human health decline is most commonly manifested by pain and sometimes fever in the initial phase of the disease. Analgesics, antipyretics and anti-inflammatories serve as drugs with various chemical structures which showcase in different proportions their main actions. They represent medicines that suppress pain and fight fever. The aim of the paper is studying the usual types of therapeutic indications using modern spectral analysis, based on the analgesic, antipyretic and anti-inflammatory actions. The following spectral analysis methods are used to control the chemical compositions of the studied drugs: UV-VIS analyses and IR analyses.

This article reports the biomarkers of the Mild Cognitive Impairment (MCI) among the elderly group aged around 60-75 years old by analyzing the EEG signals recorded by using the quantitative electroencephalograph (qEEG). There is growing evidence that EEG analysis in resting state condition are useful in early detection of neural signatures of Alzheimer’s and dementia. EEG findings and analysis shows potential of discriminating MCI, Alzheimer’s and dementia. In this research, the purpose is to 1) develop the indexes for each of the EEG bands and sub-bands such as delta (1.5 – 3.5 Hz), theta (3.3 – 7.5 Hz), alpha ( 8 – 12 Hz), beta 1 (15 – 18 Hz) and beta 2 (22 – 30 Hz); 2) provide reference for early diagnosis; 3) extract and analyze the brainwave pattern of MCI and cognitively healthy group. This study involved 19 channel resting state EEG from a total of 30 subjects, 18 diagnosed as having MCI and 12 cognitively healthy elderly with criteria for inclusion if the mini mental state examination (MMSE) score is more than or equal to 28, based on the age and educational level. Development of qEEG index started by decomposition of EEG by performing Fourier analysis, averaging and normalizing the value from the 19 channels to obtain the z-score. Findings showed promise of utility in early detection of Alzheimer’s. Notably, 1) Increases in delta/ theta posterior temporal and prefrontal area i.e., H(6.64) vs. MCI(26.29); beta temporal region, 2) Decreases in alpha at sensory motor region i.e., H(0.27) vs. MCI(0.23).

Aim: Disclosing coronary artery disease by analyzing the rates of systolic blood pressure response to workload during exercise stress test.

Methods: 53 males with hypertension underwent exercise stress test on bicycle ergometer and coronary angiography within one month. rates of systolic blood pressure to workloads in the first stage peak exercise, second, fourth and sixth minute of recovery were analyzed and compared. Also basic characteristics of patients involved in the study were also analyzed.

Results: All systolic blood pressure to workload rates during exercise and recovery resulted higher in males with coronary artery disease and hypertension compared with hypertension but no coronary artery disease.

Conclusion: High levels of systolic blood pressure to workloads rates in males with hypertension reveal the diagnosis of coronary artery disease despite the ECG variations during exercise stress test and this are not influenced by other basic characteristics of the patients.