Analysis of mechanical stability for external fixation device Orthofix in the case of anterior-posterior bending is carried out in this paper. Device is applied to the lower leg for the case of unstable fracture. Real device is mea sured and 3D CAD model is developed. CAD model is used for numerical structural stress analysis which is car ried out using CATIA V5 software. Results for displacements are obtained for selected critical places on the device and for the place of fracture. In addition, values of principal and von Misses stresses are obtained and analyzed. Using obtained results, conclusions about mechanical stability of device are formulated.
The paper analyzes the stiffness of the Orthofix external fixation system at axial pressure load, applied to the lower leg in case of an unstable fracture. Based on the actual construction of the Orthofix fixator, its 3D model was formed, and then a structural analysis was performed in the CATIA V5 software system. The aim of this paper is to investigate the mechanical properties of Orthofix fixator. FEM analysis of the fixator revealed displacements at characteristic points of the structure and fractures. During the FEM analysis, it is possible to change the load values, all with the aim of obtaining the best possible information about the behavior of the fixator during installation and use by the patient. Based on the results obtained from the FEM analysis, it can be concluded that the Orthofix fixative shows very good stiffness, but also that it can be improved by using newer materials, such as composite or some alloys of titanium and aluminum.
The paper aimed to examine if the mechanical characteristics (tensile strength, elongation, and friction) of the selected flexible packaging materials (BOPP and PET/PE) change after the packaging process. Some researchers have shown that mechanical characteristics can change because of the various effects to which foils are exposed (temperature, transport devices, solvents, etc.). The measurement of tensile strength and elongation was carried out according to SRPS G.S2.734, and the measurement of friction according to ASTM D 1894. The results show that there were no significant changes in the examined mechanical characteristics that could affect the functionality of the packaging.
Various toxic heavy metals have become hazardous to human health as well as the environment. This research has been focused on a biosorption/bio-removal process of chromium (III), copper (II) and lead (II) ions from an aqueous solution by utilizing lignocellulosic biomass of Citrus limon peel (CLP) powder. CLP powder biomass was selected based on dietary fibre components having greater potential to remove target heavy metal ions in order to purify wastewater by following the eco-friendly biosorption method. At optimum conditions, the observed maximum removal efficiency of 97.47, 87.13 and 95.71% for Cr, Cu and Pb ions, respectively, was observed. An investigation has been made as a work of pH, CLP amount and temperature. The presented bio-removal processes by prepared CLP biosorbent manifested as a temperature-independent. Langmuir isotherm model was found an excellent fit of the isotherm data for tested systems with the calculated biosorption capacities of 111.11 (Cr), 76.92 (Cu) and 100.00 (Pb) mg/g. The positive ΔH values for selected target heavy metal ions, except lead ions, confirmed that the reaction was spontaneous and endothermic. A cooperative mechanism of second-order and intraparticle diffusion models during the adsorption processes of all three target ions was established with a higher coefficient of determination and more closely anticipated take-up (adsorption capacity). Furthermore, the interaction of -OH and -COOH functional groups of CLP that have a major role in the removal of Cr, Cu and Pb ions from single-ion aqueous solution and/or a surface biosorption was confirmed based on the results presented by SEM-EDS and FTIR analysis. Analysis from XRD revealed peak corresponding to amorphous cellulose type I as observed by FT-IR analysis.
Mobility is a key aspect of modern networking systems. To determine how to better manage the available resources, many architectures aim to a priori know the future positions of mobile nodes. This can be determined, for example, from mobile sensors in a smart city environment or wearable devices carried by pedestrians. If we consider infrastructure networks, frequently changing the coverage cell may lead to service disruptions if a predictive approach is not deployed in the system. All predictive systems are based on the storage of old mobility samples to adequately train the model. Our focus is based on the possibility to determine an approach for adaptively sampling mobility patterns based on the intrinsic features of the human/node behavior. Several works in the literature examine mobility prediction mobile networks, but all of them are dedicated to the study of time features in mobility traces: none took into account the spectral content of historical mobility patterns for predictive purposes. In contrast, we take into account this spectral content in mobility samples. Through a set of wavelet transforms, we adapted the sampling frequency dynamically and obtained a considerable set of advantages (space, energy, accuracy, etc.). In fact, this issue covers an important role in the IoT paradigm, where energy consumption is one of the main variables requiring optimization (frequent and unnecessary mobility samplings can disrupt battery life). We performed several simulations using real-world traces to confirm the merit of our proposal.
Introduction Thyroid disease is an independent predictor of heart failure in patients. This study aimed to investigate the prevalence of thyroid dysfunction among patients with heart failure in Mogadishu, Somalia. Methods From January 2019 to January 2021, a total of 250 patients diagnosed with heart failure admitted to the cardiology outpatient and emergency departments were evaluated retrospectively. The demographic characteristics, the cause of heart failure, and the kind of heart failure were recorded. Patients were categorized into subclinical hypothyroidism, hypothyroidism, low T3 syndrome, subclinical hyperthyroidism, and hyperthyroidism. Results A total of 250 heart failure patients. The prevalence of thyroid dysfunction among heart failure patients was 35.6%. The mean age of the patients was 59.8±14 years. Males outnumbered females by 159 (63.2%). The prevalence of thyroid dysfunction was 35.6%. Out of the 250 patients that were examined, most of the patients 30(33.3%) had subclinical hypothyroidism. 23 (25.6%) had overt hypothyroidism, 15 (16.7%) had overt hyperthyroidism, 20 (22.2%) had low T3 syndrome, and two cases had subclinical hyperthyroidism. Regarding the gender status of the thyroid dysfunction, 43(48.3%) were male, and 46(51.7%) were female. Regarding heart failure types among thyroid dysfunction patients, most patients were HFrEF (n=64, 71.9%), and 25(28.1%) were HFpEF. Patients with heart failure and reduced ejection fraction (HFrEF) were more likely to have thyroid dysfunction than those with preserved ejection fraction (p = 0.012). Regarding comorbidities among heart failure patients with thyroid dysfunction, approximately half of the patients had hypertension (40.4%). Conclusion Thyroid problems are one of the most prevalent endocrine abnormalities in our practice. Subclinical hypothyroidism was the most common type of thyroid dysfunction among this population. We suggest that thyroid function be evaluated with cardiac function in patients with heart failure and followed up and treated together with heart failure.
Background: The aim of this study was to compare the level of inammatory parameters in 3 different groups of COVID-19 patients depending on severity of clinical manifestations and to dene which inammatory parameter can be used as predictor of clinical severity and outcome. A total of 51 subjects was included in this study by retrospective review of theMethods: documentation at the Clinic for Infectious Diseases of University Clinical Hospital Mostar. The following data were collected: demographic, clinical symptoms, complications, therapy, and the level of inammatory parameters (C-reactive protein at the admission, procalcitonin, leukocytes, relative neutrophils count, relative lymphocyte count). Depending on the value of paO2/O2 patients were separated into 3 groups: mild, moderate and severe group. Data entry into the tables was followed by statistical data processing using IBM SPSS Statistics v.26 and Microsoft Excel 2013. Most frequent symptoms were fever (82% of all subjects), cough (61%), trouble breathing (55%), shortness ofResults: breath (43%), chest pain (27%), muscle pain (25%), diarrhea (20%), vomiting (6%) and headache (6%). The overall mortality of this study was 35%, with a statistically much higher mortality in severe patients. Also C-reactive protein levels were higher in severe patients. Conclusions: Levels of C-reactive protein on admission were signicantly higher in patients who developed a severe clinical manifestations. Also, mortality in severe patients was statistically higher than the remaining 2 groups of patients. CRP is reported as a prognostic factor in the severity of clinical manifestations and mortality of hospitalized COVID-19 patients.
Background and Purpose: Improper distribution of health workers is a worldwide problem, especially in developing countries. The shortage of health personnel has been intensified over the past two decades as a result of the emigration of health workers from developing countries to developed ones and disparities between urban and rural regions. Materials and Methods: This cross-sectional, quantitative, and descriptive study was conducted at the University of Sarajevo, Faculty of Health Studies, for two months. The study included 203 3rd-year and 4th-year undergraduate students of all study programs. The chi-square test was used to examine the difference between students’ attitudes about leaving according to gender, grade point, foreign language learning, and high school graduation, as well as different statements of intention to leave or stay. Results: Of 203 respondents, 49(24.1%) were male and 154(75.9%) were female. Thirty-four students (16.75%) stated their attitude towards the definitive departure. Also, 129 students (63.55%) were thinking about leaving after graduation, while 40 students (19.7%) wanted to continue their life in Bosnia and Herzegovina after their studies. Almost half of the female students (49.26%) and slightly more than half of the male students (14.28%) think about leaving after their studies, with a statistically significant difference between men and women who think about leaving and those who stay. The positive attitudes, which the students who are leaving, for the most part, agreed upon were the acquisition of life experience that their occupation profile was sought in other countries, and career development and professional development. The reasons why most students consider leaving the country after their studies are due to the attitude that their education and degree are more valued in other countries, higher living standards in other fields, and career development and professional development. Conclusion: To prevent the migration of health students, retention policies are needed that target immigrant staff. These policies can be extremely important in preventing the problem of a lack of quality health staff in the near future.
1 Department of Chemistry, Faculty of Science and Education, University of Mostar, Matice hrvatske bb, 88 000 Mostar, Bosnia and Herzegovina; 2 Faculty of Agronomy and Food Technology, University of Mostar, Biskupa Čule bb, 88 000 Mostar, Bosnia and Herzegovina; 3 Department of Analytical Chemistry, Faculty of Chemistry and Technology, University of Split, Ruđera Boškovića 35, 21 000 Split, Croatia; E-mail: ante.prkic@ktf-split.hr
BACKGROUND Liver X receptor alpha (LXRA) plays important role in cholesterol and lipid homeostasis and lipid metabolism; moreover, it has been investigated as a candidate gene in a number of conditions, including onset and progression of atherosclerosis. We hypothesized that the LXRA gene rs2279238 polymorphism may be associated with the onset and progression of carotid atherosclerosis in the Slovenian cohort. METHODS 783 unrelated Slovenian patients were included in this cross-sectional case-control study: 308 patients in the group of cases with severe internal carotid artery (ICA) stenosis (> 75%) and 475 patients with hemodynamically insignificant ICA stenosis (<50%) in the control group. Medical records were used to acquire patient laboratory and clinical data. The TaqMan SNP Genotyping assay was used to genotype the rs2279238 polymorphism. RESULTS Between the case and control groups, we identified a statistically significant variation in genotype distribution (p=0.04), but not in allele frequency (p=0.13) of the LXRA gene polymorphism rs2279238. The results, also show that there is a statistically significant association (p=0.04) between the two genetic models (codominant and recessive) of the LXRA gene rs2279238 polymorphism and carotid atherosclerosis. CONCLUSION In the Slovenian cohort, we found a significant association between the TT genotype of rs2279238 and advanced carotid artery disease, suggesting that this polymorphism might be a genetic risk factor for ICA atherosclerosis.
Background: Antimicrobial photodynamic therapy (PDT) has been introduced as a potential option for peri-implantitis treatment. The aim of this study is to evaluate the antimicrobial effect of a novel technique involving a combination of 445 nm diode laser light with 0.1% riboflavin solution (used as a photosensitizing dye) as applied on a bacterial–fungal biofilm formed on implants and to compare the performance of this technique with that of the commonly used combination of 660 nm diode laser with 0.1% methylene blue dye. Methods: An in vitro study was conducted on 80 titanium dental implants contaminated with Staphylococcus aureus (SA) and Candida albicans (CA) species. The implants were randomly divided into four groups: negative control (NC), without surface treatment; positive control (PC), treated with a 0.2% chlorhexidine (CHX)-based solution; PDT1, 660 nm (EasyTip 320 µm, 200 mW, Q power = 100 mW, 124.34 W/cm2, 1240 J/cm2) with a 0.1% methylene blue dye; and PDT2, 445 nm (EasyTip 320 µm, 200 mW, Q power = 100 mW, 100 Hz, 124.34 W/cm2, 1.24 J/cm2) with a 0.1% riboflavin dye. Results: The PDT1 and PDT2 groups showed greater reduction of SA and CA in comparison to the NC group and no significant differences in comparison to the PC group. No statistically significant differences between the PDT1 and PDT2 groups were observed. Conclusions: A novel antimicrobial treatment involving a combination of 445 nm diode laser light with riboflavin solution showed efficiency in reducing SA and CA biofilm formation on dental implant surfaces comparable to those of the more commonly used PDT treatment consisting of 660 nm diode laser light with methylene blue dye or 0.2% CHX treatment.
Purpose Phosphonates, like 3-AminoPropylphosphonic Acid (ApA), possess a great potential for the therapy of bone tumours, and their delivery via cellulose nanocrystals (CNCs) seems a promising approach for their increased efficacy in target tissues. However, the immunological effects of CNC-phosphonates have not been investigated thoroughly. The main aim was to examine how the modification of CNCs with phosphonate affects their immunomodulatory properties in human cells. Methods Wood-based native (n) CNCs were modified via oxidation (ox-CNCs) and subsequent conjugation with ApA (ApA-CNCs). CNCs were characterised by atomic force microscopy (AFM) and nanoindentation. Cytotoxicity and immunomodulatory potential of CNCs were investigated in cultures of human peripheral blood mononuclear cells (PBMCs) and monocyte-derived dendritic cells (MoDCs)/T cells co-cultures by monitoring phenotype, cytokines production, allostimulatory and Th/Treg polarisation capacity. Results AFM showed an increase in CNCs' thickens, elasticity modulus and hardness during the modification with ApA. When applied at non-toxic doses, nCNCs showed a tolerogenic potential upon internalisation by MoDCs, as judged by their increased capacity to up-regulate tolerogenic markers and induce regulatory T cells (Treg), especially when present during the differentiation of MoDCs. In contrast, ox- and ApA-CNCs induced oxidative stress and autophagy in MoDCs, which correlated with their stimulatory effect on the maturation of MoDCs, but also inhibition of MoDCs differentiation. ApA-CNC-treated MoDCs displayed the highest allostimulatory and Th1/CTL polarising activity in co-cultures with T cells. These effects of ApA-CNCs were mediated via GABA-B receptor-induced lowering of cAMP levels in MoDCs, and they could be blocked by GABA-B receptor inhibitor. Moreover, the Th1 polarising and allostimulatory capacity of MoDCs differentiated with ApA-CNC were largely preserved upon the maturation of MoDCs, whereas nCNC- and ox-CNC-differentiated MoDCs displayed an increased tolerogenic potential. Conclusion The delivery of ApA via CNCs induces potent DC-mediated Th1 polarisation, which could be beneficial in their potential application in tumour therapy.
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