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Background: Coronavirus disease 2019 (COVID-19) is a contagious infection characterized by severe acute respiratory syndrome (SARS-CoV-2). Safe and effective vaccines are game-changers in the global vision of marking an end to the challenges posed by the COVID-19 pandemic. However, vaccine hesitancy due to perceived stigma and misinformation is a grave cause of concern. Objectives: To assess pre-university students' self-expressed stigma regarding COVID-19 vaccination and its association with their knowledge. Materials and Methods: A cross-sectional study was adopted for this research. A structured questionnaire approach was used to gather data from 384 students purposively at the selected pre-university college. The structured questionnaire consisted of three sections that explored the socio-demographic characteristics of the study participants, knowledge of vaccination, and self-expressed stigma, respectively. A total of 384 respondents took part in the study. Results: The study observes a low positive relationship (r = 0.25, P < 0.01) between knowledge and self-expressed stigma toward vaccination. Further, it was observed that participants from rural backgrounds had lower knowledge and self-expressed stigma scores than participants from urban settings. It is pertinent to note that participants with other sources of information had higher knowledge than those who used the internet, friends/peers, or newspapers. Both of the aforementioned findings are statistically significant. Conclusion: The interventions should revive trust in national health authorities, structured awareness campaigns by government agencies, and media coverage about the safety and efficacy of vaccines. In addition, it is also important to support citizens in ensuring that they have access to the right information from authentic sources in times of crisis.
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The present work examines the physical, thermal tensile, and chemical properties of wood skin fibers obtained from second generation Bitter Albizia (BA) tree skin. Chemical characterization of BA fibers showed the presence of various chemical contents such as cellulose of 74.89 wt. %, hemicellulose of 14.50 wt. %, wax of 0.31 wt. %, lignin of 12.8 wt. %, moisture of 11.71 wt. %, and ash of 19.29 wt. %. The density of BA fibers (BAFs) was showed 1285 kg/m3. XRD analysis of BAFs showed a crystallinity index (CI) of 57.20% and size of crystallite of 1.68 nm. Tensile strength and strain to failure of BAFs examined through tensile test were 513-1226 MPa and 0.8-1.37% respectively. TGA portrayed the thermal steadiness of BAFs as 339 °C with 55.295 kJ/mol kinetic activation energy, its residual mass was 23.35% at 548 °C. BAFs with high CI, less wax content, and better tensile strength make more suitable for making polymer matrix composites. SEM images of the BAFs surface depicted that the fiber outer surface has more rough which shows that they can contribute to hige fiber-matrix adhesion during composites preparation.
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Albizzia , Celulosa , Celulosa/química , Árboles , Lignina/química , Polímeros/químicaRESUMEN
The multidimensional purposes of grid-tied hybrid renewable system such as tracking of maximum power, increasing the power conversion efficiency, reducing the harmonic distortions in the injected current and control over power injected into the grid are presented in this paper by developing a laboratory-scale setup. To ensure continuous current operation at the shoot through mode of grid connected inverter, a switched Z-source converter is utilized at the PV side. The PWM rectifier connected with the wind turbine transforms AC power into dc. Individual power converters with conventional PI controllers have been dedicated for each power source, and control strategy uses only one reference voltage so as to increase the maximum power tracking speed from both PV and wind sources. The battery energy management is performed by artificial neural network (ANN) to enhance the stable power flow and increase the lifespan of the storage system. Finally, the voltage at the point of common coupling is fed to ANN-based space vector-modulated three-phase inverter and the converted AC power is injected to the grid. The overall system performance is measured by estimating the quality of injected power. A stable operation of the proposed microgrid system is verified by varying input and load at the grid. A continuous-time simulation model is realized in MATLAB and is validated using experimental prototype. This benchmark system provides various research scopes for the future smart grids.
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Peripheral ossifying fibroma (POF) is a relatively uncommon gingival growth that is considered to be reactive in nature and appear secondary to irritation or trauma. It presents as an exophytic growth with smooth surface. POF in older age group, observance of calcification in radiograph of excised specimen, pathologic migration, mobility and size greater than 2 cm is an occasional entity. The article presents such a rare case of POF in a 60-year-old female patient which was treated by surgical excision. This case contradicts the logic that this lesion occurs in teenagers and in second and third decades of life
El fibroma osificante periférico (FOP) es un crecimiento gingival poco común, considerado reactivo por su naturaleza y en general se manifiesta secundario a una irritación o trauma y se presenta como un crecimiento exofítico de superficie lisa. En grupos de mayor edad, el FOP muestra calcificación radiográfica, migración patológica, movilidad y un tamaño mayor de 2 cm, es de carácter ocasional. Se presenta un caso raro de FOP en una paciente de 60 años que fue tratado mediante excisión quirúrgica. Este caso, contradice su lógica de aparición en adolescentes o adultos entre la segunda y tercera década de la vida
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Humanos , Femenino , Persona de Mediana Edad , Neoplasias Óseas/cirugía , Neoplasias Óseas/diagnóstico , Neoplasias Gingivales/cirugía , Neoplasias Gingivales/diagnóstico , Fibroma Osificante/cirugía , Fibroma Osificante/diagnóstico , CalcinosisRESUMEN
Background. Multiple myeloma (MM) is a B-cell malignancy characterized by the accumulation of clonal population of plasma cells in the bone marrow (BM). A variety of angiogenic factors, proteases, reactive oxygen species and inflammatory cytokines induce the formation of an extensive and suitable BM microenvironment. Previous studies have established the importance of angiogenic factors, inflammatory molecules and oxidative stress in MM but their interplay and effect on each other are not being taken together. Methods. Circulatory levels of VEGF, angiopoietin-2 (Ang-2), IL-6 and TNF-α along with the activity of superoxide dismutase (SOD) and glutathione peroxidase (GPx) were investigated in 112 subjects including 62 MM patients and 50 healthy controls. Inter-stage analysis was done to evaluate the association of these molecules with the severity of disease. Pearson correlation was determined to find interrelationship, if any, between these molecules. Results. We have observed elevated levels of VEGF, Ang-2, IL-6, TNF-α and decreased activity of SOD, GPx in MM patients in comparison to controls. All these molecules also showed a trend with the severity of disease. We have found strong association between these factors upon their correlation and regression analysis. Conclusion. This study is a step toward understanding the indepth contribution of angiogenesis, inflammation and oxidative stress together in making BM microenvironment suitable for growth, survival and proliferation of malignant plasma cells in MM (AU)
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