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Gelin-Cesáro identities for Fibonacci and Lucas quaternions

Abstract

To date, many identities of different quaternions, including the Fibonacci and Lucas quaternions, have been investigated. In this study, we present Gelin-Cesáro identities for Fibonacci and Lucas quaternions. The identities are a worthy addition to the literature. Moreover, we give Catalan’s identity for the Lucas quaternions.

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Ricci solitons in a generalized weakly (Ricci) symmetric D-homothetically deformed Kenmotsu manifold

Abstract

The object of the present paper is to investigate the nature of Ricci solitons on D-homothetically deformed Kenmotsu manifold with generalized weakly symmetric and generalized weakly Ricci symmetric curvature restrictions.

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Binomial sequences

Abstract

We present a description of all binomial sequences of polynomials in one variable over a field of characteristic zero.

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Adhesion and Colonisation of Microorganisms on Porous TiO2 and TiO2-Silver Biomaterials

Abstract

Bone graft transplantation is one of the most common transplants in the world and there has been a significant increase in the use of biomaterials in this sector. Bone substitutes are widely used in traumatology, orthopaedics, maxillofacial surgery and dentistry. The culturing method was used to determine microorganism ability to attach and form biofilms on originally synthesised porous TiO2 and TiO2Ag ceramics. The aim of this study was to determine and compare the intensity of adhesion and colonisation of Staphylococcus epidermidis, Pseudomonas aeruginosa and Candida albicans on TiO2 and TiO2Ag ceramics. The lowest adhesion and colonisation were on TiO2Ag samples for S. epidermidis and P. aeruginosa.No C. albicans adhesion and colonisation differences were found on TiO2 and TiO2Ag ceramic samples.

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All intra-regular generalized hypersubstitutions of type (2)

Abstract

A generalized hypersubstitution of type τ maps each operation symbol of the type to a term of the type, and can be extended to a mapping defined on the set of all terms of this type. The set of all such generalized hypersubstitutions forms a monoid. An element a of a semigroup S is intra-regular if there is b ∈ S such that a = baab. In this paper, we determine the set of all intra-regular elements of this monoid for type τ = (2).

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Anthropometric Parameters and Biochemical Markers of Military Personnel Under the Influence of High Physical and Psychological Loads

Abstract

Physical fitness, health, and physical endurance are important attributes of persons in military. The purpose of the present study was to assess the changes of anthropometric parameters and of biochemical markers in blood serum for participants of a one-week combat training course (CTC) during which participants had high physical and psychological loads in combination with dietary limitation and sleep deprivation. High physical and psychological loads cause changes in the level of biochemical markers that are indicative of musculoskeletal system dysfunction. The study group included participants (n = 59) of both genders aged 23 to 30 years. Anthropometric parameters (body mass, height, body mass index) were determined. Blood plasma analyses were done before and directly after CTC. Biomarkers like lactate dehydrogenase (LDH), creatine phosphokinase (CPK), alanine amino transferase (ALT) and aspartate amino transferase (AST) were measured. Data were analysed by using SPSS 20. We determined levels of anthropometric parameters before, during and after a combat training course. The body mass decreased during the one-week training course, until the sixth day of combat training course, when the peak of physical and emotional stress was reached. The level of biomarkers lactate dehydrogenase and creatine phosphokinase sharply increased after the combat training course. A high physical load caused changes in biochemical markers, indicating musculoskeletal dysfunction in healthy young persons. The study underlines the importance of checking the health status of military personnel before and after exercises with high physical and psychological loads in order to prevent major health disorders in the combat environment.

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Antiplatelet Resistance in Patients with Atherosclerosis

Abstract

Variable platelet response to aspirin and clopidogrel is a well-known phenomenon in patients with coronary artery disease and ischemic cerebral stroke. The objective of the present study was to evaluate the frequency and possible risk factors of antiplatelet resistance in patients with cerebrovascular and cardiovascular diseases. The VerifyNow system was used to evaluate adenosine-5-diphosphate and platelet P2YI2 receptor function in patients with cerebrovascular and cardiovascular disease, who received dual antiplatelet therapy. Aspirin resistance was defined as aspirin reaction units (ARU) ≥ 550. Clopidogrel resistance was defined as Platelet Reaction Units (PRU) > 230. In the group of cerebrovascular diseases there were 13.2% (n = 27) patients with aspirin and 24.5% (n = 50) with clopidogrel resistance. However, in the cardiovascular group there were 20% (n = 9) aspirin and 11.1% (n = 5) clopidogrel resistant patients. In the cerebrovascular group, aspirin resistant patients had a lower triglyceride level (p = 0.001, r = 0.26) than aspirin sensitive patients. Clopidogrel resistant patients had a significantly higher level of glycated haemoglobin (HbA1C) (p = 0.016, r = 023), triglycerides (p = 0.033, r = 0.16) and lower level of high-density lipoproteins (p = 0.027, r = 0.16) than clopidogrel sensitive patients. In the cardiovascular group, patients who were resistant to aspirin had a significantly higher high-density lipoprotein level (p = 0.038, r = 0.31). No other factors differed significantly between the aspirin or clopidogrel resistant and sensitive patients in the cardiovascular group. Aspirin resistance was more common in patients with cardiovascular disease, and clopidogrel resistance in patients with cerebrovascular disease, although the difference was not significant. Our findings indicate that diabetes mellitus and an elevated level of lipoproteins could be risk factors for aspirin or clopidogrel resistance in patients with cerebrovascular diseases. Further studies should be conducted using larger patient cohorts with balanced groups of patients to investigate clinical aspects of antiplatelet resistance.

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Association of Non-Invasive Markers of Liver Fibrosis with HCV Coinfection and Antiretroviral Therapy in Patients with HIV

Abstract

The aim of this study was to assess the main effects and interaction between viral hepatitis C (HCV) coinfection and antiretroviral therapy (ART) by using a nonparametric ANOVA on direct and indirect markers of liver fibrosis in HIV-infected patients. The sample included 178 HIV patients aged from 23 to 65 (36% females). The following parameters were determined in blood of patients: hyaluronic acid, pro-matrix metalloproteinase-1, alanine aminotransferase, aspartate aminotransferase, and platelet count. The FIB-4 index was also calculated. The nonparametric ANOVA revealed no significant interaction between HCV coinfection and ART. This provides evidence for an independent contribution of each factor on promotion of the pathology. The results also demonstrated that the direct and indirect indicators of liver fibrosis are associated differently with the studied factors. Therefore, a combination of markers should be used for monitoring of liver fibrosis in HIV-infected patients.

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Choice of the Acetabular Component Placement in Dysplastic Hip Patients

Abstract

Total hip arthroplasty (THA) in patients with hip dysplasia is a challenging surgical operation. Many orthopedic surgeons concur that the anatomical placement of the acetabular components of endoprostheses (AC-EPs) during THA yields the best result. However, there are advocates of the high rotation center of the hip joint after replacement surgery. In our study, we compared the outcomes of THA based on the placement of acetabular cups to identify the most favorable site for AC-EPs in patients with varying grades of dysplastic osteoarthritis. Our study included 88 patients with dysplastic hip osteoarthritis who underwent 106 THAs during a three-year period using cementless fixation endoprostheses. Functional results were assessed by Merle d’Aubigne and Postel’s method and by instrumental gait analysis (IGA). Gait deviation index was calculated based on IGA to compare results in different acetabular component placement groups. Functional assessment of patients by Merle d’Aubigne and Postel’s grading method and IGA showed no significant difference in results due to the placement of the acetabular component. Most complications were found in the severe dysplasia patients group with the anatomical placement of the AC-EP. The appropriate location of cementless acetabular cups during THA in dysplastic hips depends on the grade of dysplasia, expected elongation of the leg, and the potential for adequate bone coverage for the AC-EP. In cases of severe dysplasia, the placement of the AC-EP in the secondary socket can provide a good functional outcome and reduce the risk of complications.

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Clinical and Sociodemographic Characteristics in First-Episode Psychosis Patients in a Rural Region of Latvia

Abstract

The first psychosis is a crucial point for further development of mental disorders. Previous evidence has demonstrated that psychotic disorders, including schizophrenia, are associated with a large number of years living with the disability. It is a global aim to improve prognosis of psychotic disorders, especially in rural regions, where mental health care possibly is not so easily accessible for patients. The aim of this study was to investigate clinical and sociodemographic determinants in association with patient and illness related factors to improve knowledge and understanding of first time psychosis patients in a rural region. This is a descriptive, cohort-based study of all consecutive first episode psychosis (F20, F23, ICD 10) patients admitted in the Daugavpils Psychoneurological Hospital (DPNH) between January 2016 and December 2017. Of the 94 first-time patients hospitalised in DPNH with symptoms of psychosis, 69 met the inclusion criteria. Our results showed that median age of patients was 33 years (IQR 27.5–42.0), median duration of untreated illness (DUI) was 30 months (IQR 11.0–60.0), and median duration of untreated psychosis (DUP) was 8 weeks (IQR 4.0–48.0). The results showed that 55.1% of first psychosis patients had not seen any health care specialist before being admitted to the psychiatric hospital. We found statistically significant differences between some sociodemographic aspects in DUI/DUP. Patients who lived with relatives had the longest DUI — 36 months, compared with 12 months for those who had established their own family. Unemployed patients had longer DUI — 36 months, compared with 12 months for employed patients. Similar findings were shown for associations with DUP. To our knowledge this study adds several important findings that help to better understand first psychosis patients.

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