bluuebunny/crossref_metadata_2025 huggingface dataset:
Closure of oronasal fistula by palatal rotational flap: case report with two years follow-up
Authors: Toptaş Orçun , Bulut Sinan , Canbolat Murat
Published: July 2019

Background/Aim: Hard palate fistulas are due to pathologies such as noma, syphilitic gom, leprosy, leishmaniasis, radiotherapy, removal of cysts or tumors of the sinus or palate, trauma or tooth attraction. Symptoms of palatal fistulas include hypernasality in the phonation due to nasal air escape during a speech, nasal cavity fluid flow, and infection due to food accumulation. Surgical repair of palatal perforations is technically difficult and complicated. Different surgical methods can be used depending on the size and location of the defect. Among these techniques, the locoregional flap types used are palatal flap, nasolabial flap, a buccal fat pad and tongue flap. Case Report: In this case report, we presented a patient with oronasal fistula due to a previous surgical operation, which was surgically closed by a palatal rotational flap. Conclusions: As a result, the oronasal communucation was relieved by successful closure of the defect and the donor area healed uneventfully.
Guided tissue regeneration in surgical endodontic treatment: Case report and literature review
Authors: Sidiropoulos Konstantinos , Roussou Konstantina , Intzes Lambros , Economides Nikolaos
Published: July 2019

Background/Aim: Guided tissue regeneration is widely used in endodontic surgery. The aim is to aid in the healing process and bone regeneration and provide more successful and predictable outcomes. Case report: This case report describes the successful treatment of an endodontic-periodontal lesion (with primary endodontic involvement), including root canal retreatment and endodontic surgery with the use of GTR (collagen absorbable membrane-xenogeneic bone graft). CBCT examination was used to aid in diagnosis and in the follow-up examination after two years to provide additional confirmation of the healing process. An extensive literature review was undertaken focusing on clinical studies that assessing the added benefit of GTR in surgical endodontics. The clinical and radiographic examinations showed uneventful healing and the reconstruction of the buccal plate and periapical area. The patient remained asymptomatic throughout the entire two years period after surgical intervention. A literature review concluded that lesion type, lesion size and the selection of the biomaterial are important factors that influence the outcome of GTR in comparison control groups. A favorable outcome was found in cases of large periapical lesions (>10mm), through-through lesions and with the use of an absorbable membrane, with or without a bone graft. Conclusions: GTR is thought to provide an added benefit in bone regeneration and the healing process in specific cases. The outcomes in the case report are consistent with the conclusions of literature review.
Discriminating between nesting and non-nesting habitat in a vulnerable bird species: implications for behavioural ecology
Authors: Hanane Saâd
Published: July 2019

Nowadays, partitioning amongst nesting and non-nesting habitats is not much studied. Here, I investigate whether or not the turtle dove (Streptopelia turtur) nesting habitats overlap with those used for other purposes in a North African agroforestry system. A total of 33 nest points and 33 turtle dove presence points were considered. The study, conducted in May to June 2017, attempted to determine the factors that may play a role in discriminating between the nesting habitats and non-nesting habitats. I used a linear discriminant analysis (LDA) to test the relevance of proximity of food resources, forest edge and human presence variables in the distribution of the species. The results show substantial segregation in the habitats selected for nesting and those selected for other uses [average distance was 1129.69 ± 169.40 m (n = 66) with a maximum of 1518.6 m and a minimum of 617.72 m], with selection depending primarily on the proximity to forest edge and feeding areas. I discuss these findings and their implications on behavioural ecology and future researches of this vulnerable species. I suggest guidelines for future studies that will seek to better understand the behavioural dynamics of turtle doves in the Mediterranean agroforestry systems. This can only be done when disturbance covariates, such as: (i) forest logging, (ii) cereal harvesting and (iii) hunting and predation pressures, were imperatively taken into account.
A Rare Case of a Tuberculosis Patient with Sarcoidosis
Authors: Muntean Petru-Emil
Published: July 2019

Background: Sarcoidosis and tuberculosis are chronic diseases that rarely occur concomitantly. We present the case of a 39-year-old woman with microbiological confirmation of pulmonary tuberculosis and concomitant sarcoidosis. Four weeks after corticosteroid therapy for sarcoidosis was introduced we had positive findings of mycobacterium culture from bronchial aspirate. Based on these results, corticosteroid therapy was discontinued and the patient received anti-tuberculosis therapy for six months as required by the national guidelines. During this period, new nodes on face, nose, and ear appeared and the patient was diagnosed with skin sarcoidosis. The patient received colchicine and corticosteroids as per the national guidelines.

Conclusion: In cases of diagnostic uncertainty between sarcoidosis and tuberculosis we should administer corticosteroid therapy until we have microbiological confirmation of mycobacterium culture.
Effects of Pramipexole on Learning and Memory Processes in Naïve and Haloperidol-challenged Rats in Active Avoidance Test
Authors: Mihaylova Anita S. , Kostadinov Ilia D. , Doncheva Nina D. , Zlatanova Hristina I. , Delev Delian P.
Published: July 2019

Background: Parkinson’s disease (PD) is the second most common neurode-generative disease, usually detected by its motor symptoms. The non-motor symptoms, including cognitive deficits, have been of great interest to researchers in the last few decades.

Aim: To assess the effect of pramipexole on learning and memory in naïve and haloperidol-challenged rats.

Materials and methods: Male Wistar rats divided into 9 groups (n=8): naïve - saline, pramipexole 0.5; 1 and 3 mg/kg bw; Haloperidol groups - saline, haloperidol, haloperidol + pramipexole 0.5; 1 and 3 mg/kg bw. Two-way active avoidance test (TWAA) and activity cage were performed. The studied parameters were: number of conditioned and unconditioned responses, vertical and horizontal movements. Statistical analysis was done using SPSS 19.

Results: The naïve experimental groups significantly increased the number of conditioned responses during the tests for short- and long-term memory, compared with the saline groups (p<0.05). During the short-memory test only the animals with the lowest dose of PMX significantly increased the number of unconditioned responses whereas during the long-term memory test all experimental groups increased the number of escapes in comparison with the saline groups (p<0.05). Challenge dose of haloperidol attenuates learning and memory in pramipexol treated rats. Only the highest dose of pramipexol showed significant increase in conditioned and unconditioned responses compared with the haloperidol group (p<0.05).

Conclusion: Pramipexole improves learning and memory in naïve rats by enhancing dopaminergic neurotransmission. This is probably not the only mechanism involved. This is confirmed by the decrease in learning and memory ability in rats with haloperidol-challenge.
Laparoscopy-Assisted Transanal Total Mesorectal Excision
Authors: Penchev Dimitar K. , Ivanov Plamen G. , Mutafchiyski Ventzislav M.
Published: July 2019

Background: Rectal cancer located in distal third still remains a technical challenge for surgeons. Transanal total mesorectal excision with laparoscopic assistance is quite new surgical approach for rectal cancer treatment that seems to solve some of the associated technical issues. The aim of the study was to present our experience in laparoscopy-assisted transanal total mesorectal excision.

Materials and methods: After obtaining approval from the local Ethics Committee, a single centre prospective double-arm comparative non-randomized trial was initiated. With recruiting still in progress at present, between 27.02.2017 and 01.10.2017 four laparoscopy-assisted transanal total mesorectal excision procedures and two laparoscopic total mesorectal excisions were performed in the department of Endoscopic Endocrine Surgery and Coloproctolgy at the Military Medical Academy in Sofia.

Results: There is no conversion in both groups. No postoperative mortality 30 days after surgery. The quality of total mesorectal excision was satisfactory in all patients estimated by the Quirque classification. There was no distal or proximal tumor involvement of surgical margins. In one of the cases, we reported positive circumferential resection margin. We had two cases with postoperative morbidity.

Conclusion: Transanal total mesorectal excision with laparoscopic assistance is quite new minimally invasive surgical approach for rectal cancer treatment. Avoiding the procedure-related complications during the learning curve is essential before applying the method to every patient. Multicenter randomized control trial is needed so that we could answer the questions raised in this study.
Pharmacoeconomics of Bronchial Asthma
Authors: Ivanova Zlatina I. , Ivanov Yavor Y.
Published: July 2019

Introduction: Pharmacoeconomics (PE) treats the problems of pharmacotherapy policy, drug marketing and reimbursement and clinical trials. It guides policy makers for effective health resources utilization and determines the profitability of the new drugs on the basis of their price, efficacy and benefits for society.

Types of health costs and pharmacoeconomic analyses: In the current review the main types of health costs are discussed. The main PE analyses with their advantages and disadvantages are presented.

Pharmacoeconomic of bronchial asthma: The main aspects of PE of bronchial asthma are available in the current review. The costs of health services (direct and indirect), the educational programs and asthma medications in different countries are discussed. Recently published data showed correlation between asthma cost and disease severity, control, social status and therapy adherence.

Conclusion: PE analyses provide the benefit of making cost consistent decisions in the field of asthma care. This review adds more data on the cost of current asthma treatment worldwide and in Bulgaria.
Relationship between Lipid Indices, Type IV Collagen Turnover and the Development of Microvascular Complications in Diabetic Patients with Arterial Hypertension
Authors: Nikolov Asparuh , Tzekova Maria , Blazhev Alexander
Published: July 2019

Background and aims: An important factor in the development of vascular wall lesions is the degradation of the major protein of connective tissue - type IV collagen. Type IV collagen peptides (CIVDP) derived from this degradation are present in the circulation and are a stimulus for production of anti-collagen type IV antibodies (ACIVAbs) IgM, IgG and IgA. The aim of this study was to find a possible association between ACIVAbs, lipid indices and the development of microvascular complications.

Materials and methods: Sera of 93 patients (mean age 61.4±11.3 yrs, diabetes duration 9.88±3.12 yrs; hypertension duration 9.28±4.98) with type 2 diabetes mellitus (T2DM) and arterial hypertension (AH) were investigated. ACIVAbs was determined using ELISA and then compared to serum ACIVAbs in 42 age- and sex-matched controls. Diabetics were divided into two groups according to presence (group 1, n=67) or absence (group 2, n=26) of microangiopathy. Lipid profile and lipid indices (log TG/HDL, LDL/HDL, TC/HDL and TG/HDL) were examined too.

Results: Patients with T2DM and AH showed statistically significant higher levels of serum ACIVAbs IgG than healthy controls [0.298 (0.237÷0.381) vs 0.210 (0.149÷0.262), KW=14.01, p<0.0001]. Group 1 had statistically significant higher levels of ACIVAbs IgG than patients without microangiopathy [0.323 (0.243÷0.391) vs 0.241 (0.207÷0.291), KW=7.66, p=0.006] and healthy controls [0.210 (0.149÷0.262), KW=17.52, p<0.0001). ACIVAbs IgG showed correlation with duration of diabetes (r=0.49, p=0.01), retinopathy (r=−0.20, p=0.04) and BMI (r=−0.24, p=0.05), HbA1c (r=0.21, p=0.04), SBP (r=0.16, p=0.05). ACIVAbs IgG correlated with log TG/HDL (r=0.21, p=0.01), LDL/HDL (r=0.19, p=0.02) TC/HDL (r=0.16, p=0.05) and with TG/HDL (r=0.15, p=0.05).

Conclusion: Our study shows relationship between elevation of ACIVAbs IgG, high lipid indices and development of microvascular complications in patients with type 2 diabetes mellitus and arterial hypertension.
Screening of Cervical Cancer: Visual Inspection with Acetic Acid (VIA) and Site of Lesion Verified by Multiple Punch Biopsies
Authors: Gad Monira M. , Galal Salma B. , Helmy Wafaa , Abd El-Fattah Naela H
Published: July 2019

Background: Cervical cancer is the tenth most frequent cancer in Egyptian women. The Papanicolaou screening test is not suitable for rural area as most follow-up consultations never take place.

Aim: To evaluate visual inspection of the cervix with acetic acid as a screening test.

Materials and methods: According to the inclusion criteria, women aged 25-60 years commuting to a gynecological out-patient clinic at the University Hospital went through a visual inspection of the cervix with acetic acid (VIA). Exclusion criteria were women below 25 years, unmarried, pregnant, menstruating, known to have cancer, having a precancerous lesion or a cervical operation. Multiple punch biopsies were done for all VIA positive cases and a subsample of the VIA negative cases underwent the same. Cervical intraepithelial neoplasia (CIN) was evaluated. In addition, the site of the lesion was assessed. SPSS was used for the statistical analysis.

Results: Of the 379 screened women, 17.1% were found to be VIA positive. The sensitivity was found to be 91.3% (79.6%–96.5%) and the specificity 68.5% (57.1%–77.9%). Significantly more women with positive punch biopsies complained of contact bleeding than those with negative punch biopsies. CIN2 and CIN3 were mostly found (77.8%) in the right quadrant, while 74% of CIN1 was found in the lower right and left quadrant.

Conclusion: VIA is weak as a test to stand alone but may need a combination with other indicators such as the location of the lesion on the right side of the cervix or contact bleeding. A combined indicator may detect precancerous cervix.
Bisphosphonate-associated Osteonecrosis of the Jaws: a Survey of the Level of Knowledge of Dentists about the Risks of Bisphosphonate Therapy
Authors: Hristamyan-Cilev Meri A. , Pechalova Petya P. , Raycheva Ralitsa D. , Hristamyan Veselka P. , Kevorkyan Ani K. , Stoilova Yordanka D.
Published: July 2019

Introduction: Bisphosphonate-associated osteonecrosis of the jaws (BAONJ) is a side effect of treatment with bisphosphonate (BP). Reports of this complication have increased recently.

Aim: To evaluate the level of knowledge of dentists from Plovdiv, Bulgaria, about possible complications of bisphosphonate therapy of patients in dental practice.

Materials and methods: Three hundred and twenty-three dental practitioners from Plovdiv, Bulgaria, took part in an anonymous survey containing 25 questions, designed to evaluate the knowledge of dentists about the complications of BP therapy.

Results: Oral and maxillofacial surgeons have the best knowledge about the indications and side effects of BP therapy, while dentists with a specialty in Pediatric Dentistry and General Dentistry have insufficient knowledge. Of the respondents, 17.03% are absolutely uninformed about BP and their side effects, and 1/2 declare that they have never had a patient with complications from BP therapy in their practice, probably due to a lack of awareness of the problem. Approximately half of the dentists we surveyed agree to carry out prophylactic examinations of patients receiving BP and know what the prophylactic examination includes. Only 15.48% of the respondents have correctly responded that in order to be treated as clinically healthy, patients should have stopped taking BP for more than 10 years.

Conclusion: With the exception of specialists in Oral and Maxillofacial Surgery, dental practitioners in Plovdiv and the region are poorly informed about the complications associated with BP therapy. Therefore, efforts must be made to make these dentists better informed about BAONJ, especially about the methods and means of preventing this condition.
Trends in the Acute Hepatitis B and Acute Hepatitis C in Bulgaria
Authors: Baymakova Magdalena P. , Karcheva Milena
Published: July 2019

Introduction: Bulgaria joined European Union (EU) on 1 January 2007. Since the accession all regulations, directives, decisions, recommendations, and opinions of the European Parliament, the Council of the European Union, and the European Commission are being implemented.

Aim: The purpose of this study was to present the morbidity of acute hepatitis B virus (HBV) and acute hepatitis C virus (HCV) in Bulgaria before and after accession to the EU.

Materials and methods: A retrospective study was performed. The morbidity of acute HBV and acute HCV infections in Bulgaria was analyzed over a period of sixteen years (2000−2016). The collected data were based on the National Center of Infectious and Parasitic Diseases (NCIPD) and the National Center of Public Health and Analyses (NCPHA).

Results: Between 2000 and 2016, 11038 cases of acute HBV infection and 1681 cases of acute HCV infection were reported in Bulgaria. Before the accession to EU, the morbidity rates of acute HBV and acute HCV infections were 12.77 cases per 100 000 population (95% CI: 11.45–13.97) and 1.52 cases per 100 000 population (95% CI: 1.17–1.96), respectively. After the accession to the EU, the morbidity rates of acute HBV and acute HCV infections were 5.29 cases per 100 000 population (95% CI: 3.86–6.73) and 1.14 cases per 100 000 population, respectively.

Conclusion: Analysis of the data suggests that there is a tendency for lower morbidity rates of acute HBV. The situation with acute HCV is relatively stable over the years regardless of EU membership.
Thyroid Gland as a Target of Secondary Malignancies - an Autopsy Study and Review Data
Authors: Mistelou Antigony , Papadatos Stamatis S. , Kousi Chrysavgi , Lampri Evangeli , Mitsis Michael , Vougiouklakis Theodoros , Galani Vasiliki
Published: July 2019

Aim: Secondary malignancies of the thyroid gland are rarely diagnosed but their incidence at autopsy is not uncommon.

Materials and methods: To investigate the clinicopathological features of patients with metastatic tumours of the thyroid gland, we reviewed autopsy records and pathological features of 36 cases with thyroidal secondary tumours from 266 cases of malignant neoplasias (excluding cases of primary thyroid cancer), over a 16-year period.

Results: There were 19 men and 17 women in the study, ranging in age from 37 to 95 years (mean 70.4 years). The incidence of metastasis in thyroid gland was 0.9% in all autopsy cases, and 13.53% of the malignant tumours. The majority were carcinomas of epithelial origin. The lung was the most common primary tumour site (33.3%), followed by the breast (8.33%) and the kidney (8.33%). The most common non-epithelial malignancy was lymphoma, followed by leukaemia (total of both 25%). As for the microscopic morphological observations, diffuse infiltration pattern of tumour cells was noted in 63.89% of the cases, the formation of nodules in 33.33% of the cases and contiguous invasion in 2.79% of the cases. There were 35.71% cases of metastases associated with multinodular goitre and 28.57% cases associated with papillary microcarcinoma.

Conclusion: Our study indicates that thyroid secondary malignancies are not infrequent and may constitute a diagnostic problem. Lung cancer is the most common neoplasm that metastasizes to the thyroid gland in north-western Greek population.
Genetics of Thyroid Disorders
Authors: Cortés Jessica María Rodríguez , Zerón Hugo Mendieta
Published: July 2019

Background: Thyroid diseases are the most common endocrine pathologies second to diabetes. They have been shown to have high genetic impact, and variants in any of the genes involved in the metabolism of thyroid hormones have marked influence on the development of these diseases.

Aim: To identify the genes that have been most involved in the development of thyroid pathologies by reviewing the literature with recent relevant articles.

Materials and methods: We performed a literature search on the NCBI (National Center for Biotechnology Information) databases, and that of the European Bioinformatics Institute (EMBL-EBI) using keywords related to the topic of interest).

Results: Activation of oncogenes such as RAS, BRAF, RET/PTC and the overstimulation of the PI3K/AKT pathway plays an important role in thyroid tumorigenesis. SLC5A5, SLC26A4, TG, TPO, DUOX2, DUOXA2 are related to hypothyroidism. Risk factors for Graves’ disease are associated with the presence of HLA-DR3, CTLA4, PTPN22, CD40, IL2RA (CD25), FCRL3, and IL23R. FOXE1 can be associated to hypothyroidism and papillary thyroid cancer.

Conclusions: Thyroid diseases are polygenetic, and while there are sufficient pathways affected by genetic changes, and there is, to our knowledge, no gene that has been found to be specifically causal, and the pathology has been the result of the interaction of many genetic variables such as polymorphisms or mutations.
Desaturation during Physical Exercise in COPD Patients – a Stable-over-time Phenomenon
Authors: Kalinov Roman I. , Marinov Blagoi I. , Stoyanova Dimitrina I. , Hodgev Vladimir A. , Vladimirova-Kitova Lyudmila G. , Nikolov Fedya P. , Kostianev Stefan S.
Published: July 2019

Introduction: Exercise-induced desaturation is a common finding in patients with moderate and severe COPD. It is an important marker in the course of disease that has a prognostic value for mortality risk.

Aim: To monitor over time COPD patients with and without desaturation during 6-minute walking test (6MWT) and to assess the stability of that phenomenon.

Materials and methods: A 6MWT was administered to 70 patients with COPD which ranged in severity from stage 2A to stage 4D (GOLD 2011); the patients had a mean age of 64.5±10.1, mean pack-years - 38.8±21, FEV1% = 46.4%±15.7%, FVC% = 73.7%±1.3%, MRC = 2.31±0.84, CAT = 20.8±6.6. Oxygen saturation was monitored during the test; indications for desaturation were a decrease of SpO2 by ≥4% and a fall in SpO2 to ≤88% for at least 3 min. The patients were followed-up for mean 40.9±22.3 months and tests were repeated.

Results: Patients were divided into two groups based on the decrease in SpO2: Group A included patients with desaturation (n=35) and Group B – patients with no desaturation (n=35). In 66 of the patients the desaturation profile was stable over time. Only two patients, who did not desaturated at baseline, experienced desaturation in the follow-up 6MWT and another two patients, who desaturated at baseline, did not have it later in the follow-up.

Conclusion: Desaturation is a phenomenon that is persistent over time. Based on the results, it could be concluded that exercise-induced desaturation is a major marker of a particular COPD phenotype.
Anatomical Variations of the Musculocutaneous and Median Nerves: A Case Report
Authors: Darvishi Marzieh , Moayeri Ardeshir
Published: July 2019

The musculocutaneous nerve is a large terminal branch of the lateral cord of the brachial plexus. It passes under the pectoralis minor and penetrates the coracobrachialis muscle, descending between the biceps brachii and brachialis muscles in the arm. After dissection in upper extremities in a 28-year-old male cadaver, the median and musculocutaneous nerve were found to have variations on the right side where the musculocutaneous nerve formed communications with the median nerve. The median nerve innervated muscles of the front of the arm in this cadaver. In addition, the musculocutaneous nerve did not pierce the coracobrachialis muscle on the right side. Knowledge of these variations is extremely important when planning a surgery in the region of axilla.
Comparison of the Safety and Efficacy of Intravitreal Ranibizumab with or without Laser Photocoagulation Versus Dexamethasone Intravitreal Implant with or without Laser Photocoagulation for Macular Edema Secondary to Branch Retinal Vein Occlusion
Authors: Kumar Prashant , Sharma Yog Raj , Chandra Parijat , Azad Rajvardhan , Meshram Girish Gulab
Published: July 2019

Background: There is an ambiguity regarding the therapy of choice for patients with macular edema following branch retinal vein occlusion (BRVO).

Aim: The purpose of the study was to compare the efficacy and safety of ranibizumab (3 injections 0.5 mg) versus ranibizumab (1 injection 0.5 mg) with laser photocoagulation (LP) versus dexamethamethasone intravitreal (IVT) implant (0.7 mg) with or without LP in patients with macular edema following BRVO.

Materials and methods: 60 eyes of 60 patients were divided into 4 groups. Group 1 received IVT ranibizumab (3 injections 0.5 mg), Group 2 received IVT ranibizumab (1 injection 0.5 mg) + LP, Group 3 received dexamethasone IVT implant (0.7 mg), and Group 4 received dexamethasone IVT implant (0.7 mg) + LP. The endpoints were the difference in mean changes in best corrected visual acuity (BCVA), central macular thickness (CMT), and inter-group differences in contrast sensitivity (CS), retinal sensitivity (RS), and intraocular pressure (IOP).

Results: BCVA gains in Group 1 (18.00±8.51) patients were significantly (p < 0.05) higher than patients in Groups 2 (10.00±10.26), 3 (9.50±9.60), and 4 (10.50±10.97), after 6 months of therapy. No significant inter-group variation was found in the CMT, CS, and RS.

Conclusions: Ranibizumab (3 injections 0.5 mg) showed significantly higher BCVA gains at 6 months post-therapy. Improvements in the BCVA, CMT, CS, and RS were comparable initially in all the therapies.
Evaluation of Kidney Function Parameters in Diabetic Rats Following Virgin Coconut Oil Diet
Authors: Akinnuga Akinjide M. , Bamidele Olubayode , Adewumi Anthony J.
Published: July 2019

Background: Diabetes mellitus (DM) leads to disruption of kidney function parameters (KFPs) which are markers of kidney diseases, especially nephropathy. Virgin coconut oil (VCO) has been implicated in playing a significant role in DM management. However, its role on KFPs in DM is scarce.

Aim: To evaluate the kidney function parameters following VCO diet in diabetic rats.

Materials and methods: : Twenty-five (25) male rats of 150 – 200 g were divided into 5 groups (n=5): Non-diabetic control (Group 1), diabetes control (Group 2), diabetes + metformin (Group 3), diabetes + 10% VCO (Group 4) and diabetes + 20% VCO (Group 5). Apart from Group 1, other groups were given intraperitone-ally 50 mg/kg of streptozotocin to induce diabetes mellitus. After 72 hours, fasting hyperglycaemia was confirmed by glucose oxidase method. All the rats were fed normal rat chow for 8 weeks. At 8th week, serum and urine samples were analysed for biochemical analysis. After 8 weeks, Group 1 and Group 2 continued to be fed on normal rat chow while other groups were treated with diets (VCO) or drug (metformin) for 4 weeks. At 12th week, urine samples were collected for biochemical analysis, the rats were sacrificed, and blood samples were collected by cardiac puncture.

Results: There were significant differences in some KFPs in diabetes control (Group 2) compared to other experimental groups. However, there was no significant difference in glomerular filtration rate (GFR) and serum sodium in all the groups.

Conclusion: VCO supplementary diet improved the altered KFPs and could be a therapy for kidney problems.
Progress and current status of influenza researches in China
Authors: Shi Tianyun , Feng Xintong , Jie Zhijun
Published: July 2019

Influenza pandemics with different extent occur every year in the world. It can cause high morbidity and mortality, arouse fear panic in public, and attract extensive attention worldwide. This paper reviews the research progress in epidemiological characteristics, detection methods, pathogenesis, treatment and prophylactic measures of influenza in China. It will be helpful for us to understand the current situation of influenza.
Intracoronary cavitation as a cause of plaque rupture and thrombosis propagation in patients with acute myocardial infarction: A computational study
Authors: Rigatelli Gianluca , Zuin Marco , Ngo Tra T. , Nguyen Hung T. , Nanjundappa Aravinda , Talarico Ernest , Duy Le Cao Phuong , Nguyen Thach
Published: July 2019

Background and Objectives

Significant rather than moderate coronary artery stenosis has been postulated to be the main substrate of plaque rupture in acute myocardial infarction (AMI). We evaluate if cavitation could influence the coronary artery plaque rupture contributing to the progression of thrombotic process.

Methods

We reconstructed a 3D model of the left anterior descending coronary artery (LAD) after reviewing the intravascular ultrasound (IVUS) data of 30 consecutive patients with mild to severe coronary artery disease.

Results

Turbulent flow or cavitation occurs in both concentric and eccentric coronary artery stenosis (≥ 75% for the former and ≥ 50% for the latter). The analysis of vapor phase demonstrated that cavitation propagated downstream, creating microbubbles, which exploded when the fluid pressure was lower than the vapor pressure at a local thermodynamic state. The relative higher vorticity magnitude (as turbulent flow in vivo angiogram) observed on the distal cap of the atherosclerotic plaque created a higher turbulence, probably able to destabilize the plaque through a micro-erosion process.

Conclusions

Cavitation seems to be able to promote the thrombotic occlusion within the coronary vessels due the ‘constant injuries’ created by the micro-explosion of bubbles.
Design of a Three-Phase Bidirectional PWM Rectifier with Simple Control Algorithm
Authors: Frisfelds K. , Krievs O.
Published: July 2019

The paper covers the main aspects of designing a low voltage three-phase PWM rectifier for bidirectional AC/DC power flow with unity power factor. A model in Matlab/Simulink environment has been built for a 10kW active rectifier with an LCL filter connected to grid side of the rectifier. The primary goal of the model is to achieve low grid current harmonic content for frequency ranges described in worldwide applicable standards and above. LCL filter parameter design procedure is described in the paper and implemented in the rectifier model to achieve a better power quality with limitations in passive element size. A simple “p-q” theory-based voltage oriented control algorithm is used in the model and described in the present paper. Model performance is characterised by dynamic response, stability and grid parameters during simulation. The simulation results demonstrate that the modelled rectifier system is stable and the grid current harmonic content is low both in the low-and high-frequency ranges.
Utilisation of the Safety Index (Elmeri Index) as the OSH Indicator at Coal Mines
Authors: Rudakov Marat L. , Gridina Elena B. , Ershov Vyacheslav S.
Published: July 2019

The article describes the main performances of the global coal industry, as well as key occupational safety and health indicators (OSH indicators) of the coal mining industry of the Russian Federation. The main goal of the article is to present the results of research of potential utilisation of the Elmeri observation method in order to evaluate safety levels at underground coal mines. The investigation performed taking into consideration two root causes of the occupational traumatism (methane and/or dust explosions, as well as rock falls) has demonstrated good correlation between the calculated values of the safety index and results of the risk assessments at the same underground coal mine under consideration. In addition, the article includes a brief discussion of advantages and restrictions in respect of utilisation of the safety index as the OSH monitoring tool at coal mines.
Impact Modelling of Explosion of Mixture Explosive Charges on the Environment
Authors: Remez N. , Dychko A. , Besarabets Y. , Kraychuk S. , Ostapchuk N. , Yevtieieva L.
Published: July 2019

The present paper provides the modelling of the explosion of the charges of the traditional (trotyl) and new blended explosive substances: polymix GR1/8 (74 %) + KRUK2 (26 %), compolite GS6, polymix GR4-T10. As a result of the research, it has been established that when using TNT a specific impulse is formed, which is by 40 % more than an explosion of new mixed explosives, and the safe distance from the source of the explosion of such explosives is increased by 25 %–50 %. On the basis of the established dependences of excess pressure, the specific impulse on the type and mass of charge, as well as the distance from the epicenter of the explosion, an engineering method has been developed for calculating dangerous parameters of the explosion impact on the environment.
Low-Cost L-Band Receiving System Front-End for Irbene RT-32 Cassegrain Radio Telescope
Authors: Bleiders M. , Berzins A. , Jekabsons N. , Skirmante K. , Bezrukovs Vl.
Published: July 2019

Irbene RT-32 radio telescope is one of the main instruments operated by Ventspils International Radio Astronomy Center (VIRAC), which is used for participation in VLBI and single-dish mode observations, including European VLBI Network (EVN) and other astronomy projects such as recently started research on small bodies of solar system, which involves weak spectral line detection at L-band. Since start of the operation as a radio telescope, single C-X band receiver has been available at RT-32, but regular demand for L-band frequencies has been received due to its importance in spectral line science. In case of RT-32 geometry, optimum dimensions of L-band feed antenna system are inconveniently large and its installation without significant feed cone rebuilding is complicated. While work is currently ongoing to redesign the feed cone for multiple receiver support and to develop high performance L-band feed system, temporal, compact and low-cost receiver has been built and installed laterally to secondary focus, which in sense of performance and functionality has been proven to be appropriate for most of the current needs. Receiver is based on small parabolic reflector allowing one to use a compact dual circular polarized horn antenna, which together with a Cassegrain antenna forms a three-mirror system. Front-end is uncooled that allows reducing operational and maintenance costs, while still providing acceptable noise performance. Practical tests show average overall sensitivity of 750 Jy at 1650 MHz in terms of system effective flux density (SEFD). The paper describes the development of the receiver and presents the main results of performance characterization obtained at Irbene RT-32.
Evaluation Principles of the Dust Influence of Mining Enterprises on the Environment
Authors: Gendler Semen G. , Rudakov Marat L. , Kuznetsov Vladimir S.
Published: July 2019

It has been noted that the areas disturbed by open-pit mining together with the production processes in the extraction of mineral resources (drilling, blasting, transportation, etc.) have a negative influence on the environment in general and the atmosphere in particular. It has been indicated that, in percentage terms, dusting of refuse dumps and tailing dumps plays a prevailing role in the total amount of dust generated. It has been stated that the processes of formation and subsequent transfer of dust in the atmosphere depend on the combination of meteorological and mining factors that have a probabilistic nature in time and space. It has been shown that the maximum value of environmental risk characterises the level of dust influence, at which reduction environmental protection measures should be directed. The present paper proposes a procedure for evaluation of the dusty influence of mining enterprises on the environment. Under the conditions of Olenegorsk GOK, a GIS has been compiled – a project of the study area and, based on geo-information modelling, the results of calculating dust concentrations in the air have been imposed on a digital map of the area.
Sustainable Development of Information Systems for Logistics as a Tool to Strengthen the Competitive Ability on Global Markets
Authors: Štor Matjaž
Published: July 2019

The main purpose of the article is to motivate experts and researchers in the field of business informatics and logistics to interdisciplinary integration in order to develop a new concept of an information system that will help to strengthen a company's competitive ability. The article analyzes the research carried out between top managers, strategic managers and managers of logistics in the largest Slovenian companies. Two hundred companies were included in the primary survey; 60 managers were selected in a representative sample and at the end 30 leaders in statistical analysis. We sent questionnaires to our managers via e-mail. The data were processed with the statistical program IBM SPSS Statistics 19, as a method we used linear regression and multiple correlation. With the primary survey, we measured satisfaction of the managers with existing information support for logistics and found that logistical, strategic information professionals need to be even more connected, so that management decisions can then be developed and sustained. On the basis of the obtained data, it can be concluded that sufficient investment of funds in the creation of an appropriate information system fosters the development of business logistics. The originality and value of the article are reflected in the interdisciplinary view of the concept of information support of logistics in the development of new products, in the original connections of various business functions, in the possibility of designing new information solutions and in the sustainable development of new services for the market.
International Environment: Recovery and Resolution Regimes as the Pillar of the Banking Union
Authors: Festić Mejra
Published: July 2019

The purpose of the article is to present the possible regimes of bank resolution in the euro system and to highlight open questions concerning additional capital buffers and the valuation of assets according to the Bank Recovery and Resolution Directive (BRRD). The bail-in tool is used to write down or to convert certain liabilities with the purpose of restoring the capital adequacy. The valuation exercise would determine the amount of loss absorbtion to restore viability of the institution and capital adequacy. The bridge bank tool offers deeper restructuring powers to the competent resolution authority. Sale of the business tool is actually a variation of the bridge bank tool, enabling the resolution authority to transfer assets and liabilities to investors. The asset separation tool always is combined with another tool. The write-down is not a resolution tool, as it affects equity, while a bail-in tool goes further to other subordinated debt and senior debt. It is possible to establish additional resolution tools in the national legislation, as long as these tools are compatible with the principles of directive and national legislation in order to support cross-border group resolution. The issue of bank overregulation and the ability to meet the requirements without negative effects on the economy is emphasized.
Centrifugal Compressor Performance Improvement through Multi Splitter Impeller
Authors: Malik Adil , Zheng Qun , Qureshi Shafiq R. , Ahmed Salman A. , Gambo D. KB
Published: July 2019

In the paper, a back swept impeller of centrifugal compressor is experimentally studied and numerically validated and modified to increase its pressure ratio and improve efficiency, as well as to analyse the effect of splitter blade location between two main blades. The back swept multi splitter blade impeller was designed with a big splitter positioned close to the main blade suction surface and a smaller splitter close to the pressure surface. Adding this multi splitter improves the overall performance of the modified impeller due to less intensive flow separation and smaller pressure loss. In particular, the total pressure ratio was observed to increase from 4.1 to 4.4, with one percent increase in efficiency.
Polish DGPS System: 1995–2017 – Study of Positioning Accuracy
Authors: Specht Cezary , Smolarek Leszek , Pawelski Jan , Specht Mariusz , Dąbrowski Paweł
Published: July 2019

This paper is the fourth in a series of publications presenting the process of installation, testing and long-term assessment of the navigational parameters of the Polish DGPS system. This series of publications intends to present – to the general public – the accomplishments of teams of Polish scientists who have been working for years to make the DGPS the main positioning system used in the Polish sea areas. A considerable part of the materials presented in this paper has never been published.

The article presents changes in the position accuracy of the Polish DGPS system over 20 years. Both dynamic tests performed on vessels as well as static measurements campaigns were analysed. The publication contains selected results achieved in its installation and testing in 1995–1997 supplemented with the results of studies conducted in the years: 2006, 2010, 2014, 2017. During this period the position accuracy increased from 2–8 m (1996) to approx. 1–2 m (2010) due to three reasons: turning – off the Selective Availability (2000), technical modernization of reference stations (2010) and continuous – over many years – reducing GPS signal-in-space pseudorange errors, which results in increased position accuracy in all GPS augmentation systems.
Damage and Fracture Analysis of Bolted Joints of Composite Materials Based on Peridynamic Theory
Authors: Yang Na-Na , Zhao Tian-You , Gu Ji-Guang , Chen Zhi-Peng
Published: July 2019

It is clear that the advantages of fibre glass-reinforced plastics surpass those of steel, but the failure analysis of composite structures is much more complex than that of isotropic materials as composite materials may fail in a variety of ways. In order to simulate the damage and fracture of bolted joints of fibre reinforced composite, the bond-based peridynamic method suitable for elastic, brittle and anisotropic characteristics of composite material is used. The peridynamic model for composite laminate is validated by the finite element method. Then a peridynamic program of composite damage is applied to calculating the damage of bolted joint structure and the damage propagation process and failure mode of the structure is obtained.
New Designs of Centrifugal Magnetic Fluid Seals for Rotating Shafts in Marine Technology
Authors: Matuszewski Leszek
Published: July 2019

The centrifugal magnetic fluid seals have important advantage over the conventional centrifugal seals. They maintain very good sealing capacity at static, medium and high speeds of shaft rotation, with the increased seal lifetime, and minimum torque and static friction. These seals are particularly useful in cases when the angular shaft velocity varies and sometimes decreases to nearly or exactly zero, such as in flywheel applications, ship propeller main shafts, etc. Unique properties of the magnetic fluid give rare opportunities for application in marine design, where perfect sealing together with reliable lubrication are required.

The paper presents a typical design and operation principle of a centrifugal magnetic fluid shaft seal, along with new design solutions. Not only in ocean technology and underwater robotics. Some cases of application of centrifugal magnetic fluid seals in modern sealing technology are included.
Structural Reliability Assessment of Corroded Tanker Ship Based on Experimentally Estimated Ultimate Strength
Authors: Woloszyk Krzysztof , Garbatov Yordan
Published: July 2019

This work deals with the reliability assessment of a tanker ship hull structure subjected to a vertical bending moment and corrosion degradation. The progressive collapse and ultimate load carrying capacity are estimated based on experimentally tested scaled box-shaped-specimens. The translation of the strength estimate of the scaled specimen to the real tanker ship hull structure is performed based on the dimensional theory developing a step-wise linear stress-strain relationship. The load-carrying capacity is considered as a stochastic variable, and the uncertainties resulted from the scaled-specimen to the real-structure strength translation, and the subjected load of the real ship are also accounted for. A sensitivity analysis concerning the stochastic variables, included in the ultimate limit state function is performed. The partial safety factors, in the case of a scaled specimen and real structure, are also identified, and conclusions are derived.
Method of Emergency Collision Avoidance for Unmanned Surface Vehicle (USV) Based on Motion Ability Database
Authors: Song Lifei , Chen Houjing , Xiong Wenhao , Dong Zaopeng , Mao Puxiu , Xiang Zuquan , Hu Kai
Published: July 2019

The unmanned surface vehicles (USV) are required to perform a dynamic obstacle avoidance during fulfilling a task. This is essential for USV safety in case of an emergency and such action has been proved to be difficult. However, little research has been done in this area. This study proposes an emergency collision avoidance algorithm for unmanned surface vehicles (USVs) based on a motion ability database. The algorithm is aimed to address the inconsistency of the existing algorithm. It is proposed to avoid collision in emergency situations by sharp turning and treating the collision avoidance process as a part of the turning movement of USV. In addition, the rolling safety and effect of speed reduction during the collision avoidance process are considered. First, a USV motion ability database is established by numerical simulation. The database includes maximum rolling angle, velocity vector, position scalar, and steering time data during the turning process. In emergency collision avoidance planning, the expected steering angle is obtained based on the International Regulations for Preventing Collisions at Sea (COLREGs), and the solution space, with initial velocity and rudder angle taken as independent variables, is determined by combining the steering time and rolling angle data. On the basis of this solution space, the objective function is solved by the particle swarm optimization (PSO) algorithm, and the optimal initial velocity and rudder angle are obtained. The position data corresponding to this solution is the emergency collision avoidance trajectory. Then, the collision avoidance parameters were calculated based on the afore mentioned model of motion. With the use of MATLAB and Unity software, a semi-physical simulation platform was established to perform the avoidance simulation experiment under emergency situation. Results show the validity of the algorithm. Hence results of this research can be useful for performing intelligent collision avoidance operations of USV and other autonomous ships
Pre-Filtered Backstepping Control for Underactuated Ship Path Following
Authors: Liu Zhiquan
Published: July 2019

Robust path following control for underactuated surface ships is an important issue in marine control practice. This paper aims to improve the robustness of the close-loop system with model uncertainties and time-varying disturbances. A practical adaptive backstepping control scheme with a pre-filter is proposed to force a surface vessel to track the predefined path generated by the virtual ship. Based on the Lyapunov stability theorem, this algorithm can guarantee all error signals in the overall system to be uniformly ultimately bounded, and it can be implemented without exact knowledge of the nonlinear damping structure and environmental disturbances. The proposed pre-filter can smooth the commanded heading order and obtain a better performance of the waypoint-based navigation control system. Two simulation cases are drawn to illustrate the validity of the proposed control strategy.