Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 84
Filtrar
1.
BMC Public Health ; 23(1): 2154, 2023 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-37924059

RESUMO

BACKGROUND: Population health is vital to a nation's overall well-being and development. To achieve sustainable human development, a reduction in health inequalities and an increase in interstate convergence in health indicators is necessary. Evaluation of the convergence patterns can aid the government in monitoring the health progress across the Indian states. This study investigates the progressive changes in the convergence and divergence patterns in health status across major states of India from 1990 to 2018. METHODS: Sigma plots (σ), kernel density plots, and log t-test methods are used to test the convergence, divergence, and club convergence patterns in the health indicators at the state level. RESULTS: The result of the sigma convergence suggests that life expectancy at birth has converged across all states. After 2006, however, the infant mortality rate, neonatal mortality rate, and total fertility rate experienced a divergence pattern. The study's findings indicate that life expectancy at birth converges in the same direction across all states, falling into the same club (Club One). However, considerable cross-state variations and evidence of clubs' convergence and divergence are observed in the domains of infant mortality rate, neonatal death rate, and total fertility rate. As suggested by the kernel density estimates, life expectancy at birth stratifies, polarizes, and becomes unimodal over time, although with a single stable state. A bimodal distribution was found for infant, neonatal, and total fertility rates. CONCLUSIONS: Therefore, healthcare strategies must consider each club's transition path while focusing on divergence states to reduce health variations and improve health outcomes for each group of individuals.


Assuntos
Mortalidade Infantil , Expectativa de Vida , Lactente , Recém-Nascido , Humanos , Nível de Saúde , Coeficiente de Natalidade , Avaliação de Resultados em Cuidados de Saúde
2.
Heliyon ; 9(9): e20273, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37809485

RESUMO

Given the recent preoccupations of scientific environment for "resource curse" in the context of financial development, the aim of this paper is to explore more the connection between financial development and natural resources abundance/dependence in the major five gas exporters in the period 1996-2021. The panel data models based on DOLS/FMOLS approach and mean group (MG) estimator suggest that the impact of resource abundance on financial development depends on the type of indicators used to assess the financial progress, as previous studies suggested. More coal per capita and the interaction between contract intensity and total natural resources, respectively oil per capita contribute to the development of financial markets, while economic growth supports the development of financial institutions. Even if natural gas per capita is causally related to financial development, it does not exert a significant impact on it in these countries. The new international context might be an opportunity for US, Canada, China and Saudi Arabia to achieve this target.

3.
Heliyon ; 9(9): e19673, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37809608

RESUMO

Innovative Work Behavior (IWB) of employees is one of the essential requirements for organizations to excel in competition in today's dynamic world. Nowadays, organizations can keep the current pace through competitive advantage. But to acquire competitive advantage, employees must be creative and innovative in their work-related behaviors. Small and Medium Enterprises (SMEs) in Pakistan are suffering several challenges in this regard. Therefore, current study is designed to examine the role of negative events and negative leadership on the IWB of the employees with mediating role of Psychological Well-being (PsyWB). Further, the moderating role of Perceived Organizational Support (POS) has also been tested. The negative event used in current research is Workplace Incivility (WPI) and Despotic Leadership (DL) from the negative leadership styles examined. Results of the current study showed that the presence of WPI and DL in organizations damage the IWB of employees as they harm the PsyWB of employees. We find that PsyWB mediated the relationship among DL, WPI, and IWB. POS is helpful for employees to overcome the negative issues prevailing in the organizations. The SMEs need to construct policies to eradicate WPI and must discourage despotic personalities to make the environment favorable for employees to protect their IWB. There must be some events that can increase the positive PsyWB of employees to make them more creative and motivated. Likewise, POS must be at sufficient level so that employees feel safe and healthy in all respects.

4.
Environ Res ; 239(Pt 2): 117370, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37827374

RESUMO

The current research investigates the utilization of spirulina microalgae biodiesel blends in a naturally aspirated constant speed compression ignition engine with Ce2O3 nanoparticles at the concentration of 50 ppm under diverse engine loading conditions. Blends of microalgae dispersed with neat diesel at the volume of 20% and 40%. A series of tests were conducted to evaluate the combined effects of microalgae and nanoparticles on engine performance, combustion efficiency, and emission characteristics. The study revealed that increasing the microalgae concentration in the diesel fuel resulted in reduced brake thermal efficiency due to less effective atomization and lower calorific value. Surprisingly, the 20% biodiesel blend with nanoparticles exhibited the highest brake thermal efficiency across various engine loads, while the 40% blend showed higher brake specific fuel consumption compared to both the 20% blend and neat diesel, primarily because of its lower heating value necessitating increased fuel consumption. Furthermore, the biodiesel blends led to lower in-cylinder pressure than pure diesel, mainly attributable to suboptimal atomization. In terms of emissions, the utilization of microalgae-based fuel led to a significant reduction in NOx, CO, and smoke emissions, attributed to the lower cylinder temperatures associated with these blends. In conclusion, this study underscores the potential of spirulina microalgae, particularly when combined with nanoparticles at an optimal concentration, as a promising and environmentally friendly alternative for compression ignition engines.


Assuntos
Microalgas , Nanopartículas , Spirulina , Biocombustíveis , Emissões de Veículos , Gasolina , Monóxido de Carbono/análise
5.
Chemosphere ; 343: 140076, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37678600

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are omnipresent, persistent, and carcinogenic pollutants continuously released in the atmosphere due to the rapid increase in population and industrialization worldwide. Hence, there is an ultimate rise in concern about eliminating the toxic PAHs and their related aromatic hydrocarbons from the air, water, and soil environment by employing efficient removal technologies using nanoparticles as a catalyst. Here, the degradation of selective PAHs viz., anthracene and benzene using laboratory synthesized rGO-Ag-Cu-Ni nanocomposite (catalyst) was studied. Characterization studies revealed the nanocomposites exhibited surface plasma resonance at 350 - 450 nm, confirming the presence of Ag, Cu, and Ni metal ions embedded on the reduced graphene substrate. It was found that the nanocomposites synthesized were spherical, amorphous in nature, and aggregated together with measurements ranging from 423 to 477 nm. An SEM-EDX analysis of the nanocomposite demonstrated that it contained 25.13% O, 14.24% Ni, 27.79% Cu, and 32.84% Ag, which confirms the synthesis of the nanocomposite. Crystalline, sharp nanocomposites of average size 17-41 nm with an average diameter of 118.5 nm (X-ray diffraction and DLS) were observed. FTIR spectra showed that the nanocomposites had the functional groups alkanes, alkenes, alkynes, carboxylic acids, and halogen derivatives. Batch adsorption studies revealed that the maximum degradation achieved at optimum nano-composite concentration of 10 µg/mL, pH value of 5, PAHs concentration of 2 µg/mL and effective irradiation source being UV radiations in the case of both benzene and anthracene pollutants. The degradation of benzene and anthracene followed Freundlich & Langmuir isotherm with the highest R2 value of 0.9894 & 0.9885, respectively. Adsorption kinetic studies under optimum conditions revealed that the adsorption of both benzene and anthracene followed Pseudo-second order kinetics. Antimicrobial studies revealed that the synthesized nano-composite exhibited potential antimicrobial activity against Gram positive bacterium (Bacillus subtilis, Staphylococcus aureus), Gram negative bacterium (Klebsiella pneumonia, Escherichia coli) and fungal strain (Aspergillus niger) respectively. Thus, the synthesized rGO-Ag-Cu-Ni nano-composite acts as an effective antimicrobial agent as well as a PAHs degrading agent, helping to overcome antibiotics resistance and to mitigate the overgrowing PAHs pollution in the environment.


Assuntos
Anti-Infecciosos , Poluentes Ambientais , Nanocompostos , Hidrocarbonetos Policíclicos Aromáticos , Benzeno , Cinética , Antracenos , Nanocompostos/química , Adsorção
6.
Front Public Health ; 11: 1222125, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37614458

RESUMO

Our research aims to support decision-making regarding the financing of healthcare projects by structural funds with policies targeting reduction of the development gap among different regions and countries of the European Union as well as the achievement of economic and social cohesion. A fuzzy decision support model for the evaluation and selection of healthcare projects should rank the project applications for the selected region, accounting for the investor's wishes in the form of a regional coefficient in order to reduce the development gap between regions. On the one hand, our proposed model evaluates project applications based on selected criteria, which may be structured, weakly structured, or unstructured. On the other hand, it also incorporates information on the level of healthcare development in the region. The obtained ranking increases the degree of validity of the decision regarding the selection of projects for financing by investors, considering the level of development of the region where the project will be implemented. At the expense of European Union (EU) structural funds, a village, city, region, or state can receive funds for modernization and development of the healthcare sector and all related processes. To minimize risks, it is necessary to implement adequate support systems for decision-making in the assessment of project applications, as well as regional policy in the region where the project will be implemented. The primary goal of this study was to develop a complex fuzzy decision support model for the evaluation and selection of projects in the field of healthcare with the aim of reducing the development gap between regions. Based on the above description, we formed the following scientific hypothesis for this research: if the project selected for financing can successfully achieve its stated goals and increase the level of development of its region, it should be evaluated positively. This evaluation can be obtained using a complex fuzzy model constructed to account for the region's level of development in terms of the availability and quality of healthcare services in the region where the project will be implemented.


Assuntos
Atenção à Saúde , Políticas , União Europeia , Técnicas de Apoio para a Decisão
7.
Artigo em Inglês | MEDLINE | ID: mdl-37644265

RESUMO

The study's main goal was to quantify the relationships between the selected sectoral dimensions and responsible consumption and production within the Sustainable Development Goal 12 (SDG 12). The SDG 12 goal was examined through the six indicators: (i) raw material consumption tonnes per capita (RMC), (ii) average CO2 emissions per km from new passenger cars (CO2), (iii) circular material use rate, (iv) generation of waste excluding major mineral wastes by hazardousness in kilogram per capita, (v) gross value added in environmental goods and services sector percentage per GDP (VAE), and (vi) energy productivity PPS per kilogram of oil (EPO). The results of the analyses confirmed the existence of the important synergies, but also the significant compromises between the goals of sustainable development. The highest level of association with the raw material consumption was confirmed for the enterprises located in the low-tech manufacturing sector. The results are beneficial for the policymakers and development strategies, for experts dealing with the sector analyses in a relation to sustainable development, creators of the evaluation, and regulatory mechanisms supporting the sustainability of the economies and their environmental goals and strategies.

8.
Front Public Health ; 11: 1184861, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37497024

RESUMO

This study proposes an approach to the external evaluation of medical education programs' quality based on a combination of indicators, including international rankings, external stakeholders' input, and independent agencies' assessments. We modify the success equation with a detailed consideration of the skill component and its decomposition into internal and external quality assurance elements along with authority. We carried out a bibliometric analysis regarding the problem of medical education quality assessment in the context of achieving sustainable development goals. We described the calculation model of external quality assessment indicators through the algorithms of independent education quality assurance agencies' activity and rating indicators shown in the modified Mauboussin's equation. The model considers the economic component (the consequence of achievement) of skill, which is expressed in raising funds from external sources to implement educational and scientific activities. The proposed algorithm for assessing the educational program quality can be applied to benchmark educational program components, complete educational programs within the subject area, and the educational institution for different areas. We propose a "financial" model for educational program quality based on the analysis results. The model makes it possible to determine the need for additional focused funding of the educational program based on the individual analysis of the external evaluation criteria of the achievement level. This study analyzes the accreditation results of more than 110 educational programs in 2020 and 8 months of 2021 within the direction 22 "Medicine" (according to the national classification of fields of knowledge) (state and private Ukrainian medical universities).


Assuntos
Educação Médica , Avaliação Educacional
9.
Environ Res ; 232: 116263, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37247655

RESUMO

This study explores the challenges facing microalgae biofuel production, specifically low lipid content and difficulties with algal cell harvesting. The purpose of the research is to investigate the effect of seawater content and nanoparticle concentration on freshwater microalgae growth and biofuel production. The principal results of the study show that increasing the proportion of seawater and nanoparticles enhances the lipid content and cell diameter of microalgae, while excessive concentrations of nanoparticles and low seawater content lead to reduced microalgae growth. Furthermore, an optimal cell diameter was identified at a nanoparticle concentration of 150 mg/L. The study also reveals that increasing seawater content can decrease zeta potential and increase chlorophyll a content due to the concentration of dissolved organic matter. Increasing the seawater content from 0% to 25% decreased zeta potential by 1% owing to the instability and aggregation of the cells. Chlorophyll a for the 0% seawater was 0.55 which is increased to 1.32 only due to the increase in the seawater content. This significant increase is due to the concentration of dissolved organic matter in seawater. Additionally, the presence of seawater positively affects microalgae metabolic activity and biochar yield. The findings of this study offer valuable insights into the potential for optimizing microalgae biofuel production. The use of seawater and nanoparticles has shown promise in enhancing microalgae growth and biofuel yield, and the results of this study underscore the scientific value of exploring the role of seawater and nanoparticles in microalgae biofuel production. Further research in this area has the potential to significantly contribute to the development of sustainable energy solutions.


Assuntos
Chlorella , Microalgas , Nanopartículas , Chlorella/metabolismo , Clorofila A/metabolismo , Biocombustíveis , Matéria Orgânica Dissolvida , Água do Mar , Lipídeos , Biomassa
10.
Environ Res ; 231(Pt 3): 116216, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37224944

RESUMO

The present investigation explores the feasibility of generating biogas from water hyacinth (WH) through a pretreatment process. The WH samples were subjected to a high concentration of H2SO4 pretreatment to enhance biogas production. The H2SO4 pretreatment aids in breaking down the lignocellulosic materials found in the WH. Additionally, it helps modify the cellulose, hemicellulose, and lignin, which assists in the anaerobic digestion process. The samples underwent pretreatment with 5% v/v H2SO4 for 60 min. Biogas production was conducted for both untreated and pretreated samples. Furthermore, sewage sludge and cow dung were used as inoculants to promote fermentation in the absence of oxygen. The results of this study demonstrate that the pretreatment of water hyacinth with 5% v/v H2SO4 for 60 min considerably enhances biogas production through the anaerobic co-digestion process. The maximum biogas production was recorded by T. Control-1, with a production rate of 155 mL on the 15th day compared to all other controls. All the pretreated samples showed the highest biogas production on the 15th day, which is comparatively five days earlier than the untreated samples. In terms of CH4 production, the maximum yield was observed between the 25th and 27th days. These findings suggest that water hyacinth is a viable source of biogas production, and the pretreatment method significantly improves biogas yield. This study presents a practical and innovative approach to biogas production from water hyacinth and highlights the potential for further research in this area.


Assuntos
Biocombustíveis , Eichhornia , Anaerobiose , Metano , Esgotos , Nutrientes , Digestão
11.
Environ Res ; 231(Pt 1): 115958, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37086880

RESUMO

The shift in focus towards biofuels has led to the attention towards fourth-generation fuels, particularly microalgae, due to its high oil productivity and simple cultivation processes. The current study aimed to examine the effects of spirulina microalgae blends in a naturally aspirated diesel engine by testing two blend percentages (15% and 30%) and incorporating Fe2O3 nanoparticles (75 ppm). A series of test conducted in a single-cylinder engine with an optimum compression ratio of 17.5. The fuels tested include 100% diesel (D0), diesel with Fe2O3 nanoparticles (DF), diesel with 15% microalgae blends (B15), diesel with 15% microalgae blends and Fe2O3 nanoparticles (B15F), diesel with 30% microalgae blends (B30), and diesel with 30% microalgae blends and Fe2O3 nanoparticles (B30F). The results showed that the addition of microalgae blends led to a marginal increase in engine performance, while the addition of Fe2O3 nanoparticles led to a significant increase in brake thermal efficiency and decreased fuel consumption. The emissions rate was also lower compared to diesel, but the addition of Fe2O3 nanoparticles increased the oxygen content in the fuel, thereby improving the combustion rates. By ensuring the complete combustion the formation of CO2, HC and smoke intensity was also found to be significantly lower compared to diesel fuel. On the contrary, NOx increased due to the cylinder temperatures. This research highlights the potential of using microalgae as a sustainable source of biofuel, and the positive effects of adding Fe2O3 nanoparticles to enhance the fuel's efficiency.


Assuntos
Gases de Efeito Estufa , Microalgas , Spirulina , Emissões de Veículos/análise , Gasolina/análise , Biocombustíveis/análise , Monóxido de Carbono/análise
12.
Environ Res ; 231(Pt 1): 116010, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37119840

RESUMO

This study examines the effect of rice husk ash (RHA) and nanosilica, and ground granular blast furnace slag (GGBS) on concrete mechanical and durability properties. The cement had been partially replaced with nanosilica and RHA having substitution percentages up to 6% and 10% respectively whereas the sand had been partially replaced by GGBS at 20% for all mixes. A water-to-cementitious materials ratio of 0.38 and a sand-to-cementitious materials ratio of 2.04 were used to cast eight different concrete mixes. The nanosilica used in the present research possessed some favorable effects such as rich fineness, higher surface area and greater reactivity which signified one of the best cement replacement materials. Both the durability and strength of concrete specimens possessing nanosilica, RHA and GGBS was evaluated using in-elastic neutron scattering, SEM image, piezoresistive test, split tensile strength, flexural strength and compressive strength test. Concrete specimens were also subjected to chloride penetration and water absorption to examine the impact of replacement materials on the concrete's durability attributes. Concrete performance was increased by the ternary blending of concrete because of the active participation of nanosilica in durability and strength at early ages, both RHA and GGBS played an important role in improving packing density. It was found that as the percentage of cement replaced with nanosilica increases, the durability of concrete also significantly increases. But the optimum strength parameter was found when 4% of cement was replaced by the nanosilica effectively. The proposed ternary mix may be eco-friendly by saving cement and enhancing strength and durability effectively.


Assuntos
Resíduos Industriais , Oryza , Areia , Agricultura , Poeira , Água
13.
Bioresour Technol ; 374: 128802, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36858122

RESUMO

The aim of this review was to study why, despite large investments in research and development, algae biodiesel is still not price competitive with fossil fuels. Microalgal production was confirmed to be a critical cost item (84 up to 93 %) for biodiesel regardless of the production technology. Techno-economic assessment revealed the main cost drivers during mass cultivation. It is argued that a breakthrough in the cultivation efficiency of microalgae is identified as a necessary condition for achieving price-competitive microalgal biodiesel. The key bottlenecks were identified as follows: (1) light and O2 concentration management; (2) overnight respiratory loss of oil. It is concluded that most of the research on microalgae biodiesel yields economically over-optimistic presumptions because it has been based on laboratory scale experiments with a low level of interdisciplinary overlap.


Assuntos
Biocombustíveis , Microalgas , Tecnologia , Combustíveis Fósseis , Biomassa
14.
Artigo em Inglês | MEDLINE | ID: mdl-36901427

RESUMO

BACKGROUND: The state and prospects of the healthcare industry of a country are among its top priorities because the quality of life and health of its citizens are indicators of its success and competitiveness. The aim of this study is to conduct a theoretical analysis and qualitative and quantitative assessments of indicators by developing an integral indicator in the context of behavioral, social, demographic, and economic factors that characterize the level of healthcare system development in European countries using multivariate statistical modeling methods. METHODS: The study was implemented using Statistica 10 and Statistica Portable statistical packages. The statistical base of the study was formed using descriptive analysis; a group of 10 European countries was identified using a cluster analysis based on the application of an iterative divisive k-means method. The degree and significance of the interrelations between the components characterizing the studied groups of indicators were determined using canonical correlations by conducting a canonical analysis. Factor modeling is conducted by applying the analysis of the main components to determine the relevant indicators for assessing the level of healthcare system development to build integral indicators of the level of healthcare system development in European countries. RESULTS: The need to improve the level of healthcare system development in European countries was confirmed. Shortcomings and possible reserves for potential improvement of the healthcare system were identified. CONCLUSIONS: The results can help public authorities, officials and employees of the healthcare sector organize and conduct effective, timely, high-quality regulation and adjustment of the regulatory and legislative framework to improve healthcare system development.


Assuntos
Saúde Pública , Qualidade de Vida , Humanos , Europa (Continente) , Atenção à Saúde , Análise Fatorial
15.
Technol Forecast Soc Change ; 191: 122488, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36919102

RESUMO

This study aimed to assess the relationship between safety perceptions and destination image in the Central European region during the technological and social environment change brought about by the COVID-19 pandemic. The study sample consisted of respondents from three Central European countries, namely, the Czech Republic, Hungary, and Slovakia. The quantile regression analysis was used to analyze the relationship between the image of the destination and its perceived safety. The results showed that concerns about the safety of the tourism environment could be negatively associated with the image of the infrastructure in Hungary and Slovakia, with value for money in the three countries, and with images of enjoyment in Slovakia. Higher levels of destination safety may be associated with a more positive destination image, with health, facilities and services being the most important dimensions of perceived safety, because of the pandemic. This study contributes to the knowledge of the concept of destination images and the development of tourism.

16.
PLoS One ; 18(1): e0276533, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36662752

RESUMO

INTRODUCTION: Although there is a growing number of scientific publications on financial monitoring, combating money laundering, the shadow economy, and the impact of corruption on economic development, further research needs to determine the stability of the national financial system in dynamics. The dynamic stability of the national financial monitoring system subjects will allow to adequately assess the effectiveness of the existing national financial monitoring system in each country and determine the influential factors. MATERIALS AND METHODS: The article investigates an approach to identifying the dynamic stability of the national financial monitoring system subjects based on the calculation of the integrated indicator of the country's financial system propensity to ALM, vector autoregression (VAR) model taking into account time lag. The proposed integrated indicator allowed to adequately assess the existing financial monitoring systems of the countries (15 countries of the European Union for 2000-2020: Austria, Belgium, Cyprus, Estonia, Finland, France, Greece, Ireland, Italy, Latvia, Malta, Netherlands, Portugal, Slovak Republic, Spain). In addition, vector autoregression models (VAR) of the dependence of the country's financial system propensity to ALM on the regressors Government Integrity, Index of economic freedom, Monetary Sector credit to the private sector (% GDP), were built, taking into account time lags in general and for each studied country. RESULTS: According to the modeling results, the national financial monitoring systems in Austria, Belgium, Estonia, Finland, France, Ireland, Netherlands, Slovak Republic, Spain were resistant to money laundering. It is vice versa in Malta, Greece, Cyprus, Portugal, Italy, Latvia. These conclusions are also confirmed based on a binary approach. Such exogenous variables as Government Integrity (with a lag of 2 years) and the Index of economic freedom (taking into account the time delays of the regression reflection under the influence of this regressor for 1 and 2 years) have a statistically significant effect on the country's financial system. CONCLUSION: The general vector autoregression (VAR) model shows that the current value of the country's financial system propensity to ALM by 92.78% is determined by its previous value. With an increase of Government Integrity by 1%, the country's financial system's propensity to ALM will decrease by 0.000616 units with a lag of two years. The nature of the impact made by the Index of economic freedom on the performance feature was specific-when this indicator increases by 1% for a lag delay in one year, the PFSALM value will decrease by 0.001997 units, and for a lag delay of two years it will change the trend and increase by 0.003076 units per unit, respectively.


Assuntos
Administração Financeira , Humanos , Europa (Continente) , Grécia , Irlanda , Itália , Portugal , Espanha
17.
Environ Res ; 216(Pt 4): 114742, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36347393

RESUMO

The main focus of the study was to witness the effects of chicken waste-based biodiesel blends along with constant hydrogen injection in a modified diesel engine. Furthermore, the nanoparticle multiwall carbon nanotubes (MWCNT) effects on the engine efficiency were also examined. A series of tests was conducted in the single cylinder, water cooled engine fuelled with diesel, CB100N, CB10N, CB30N, and CB50N. Throughout the entire run, constant hydrogen injection of 5 LPM has been maintained. The parameters such as brake thermal efficiency, brake specific fuel consumption, heat release rate and the emissions of different pollutants were determined for a variety of engine speeds. ASTM standards were applied to measure the viscosity, density and calorific value. From the reported findings, it was clear that the addition of the chicken waste biodiesel could be a sustainable substitute for the existing fossil fuels. Although the emission of the pollutants was dropped significantly, there was a massive drop in the BTE values. To compensate such shortage of power, the biodiesel was dispersed with MWCNT at the concentration of 80 ppm. Compared to the regular biodiesel, MWCNT inclusion increased the BTE by 14%. Further, the consumption of the fuel was also reduced marginally. Considering the pollutants, the catalytic activity of the MWCNT reduced the emissions of CO, NOx, and HC at various engine speeds. Besides, 10% reduction in NOx had been reported at lower engine speeds and was reduced to 8% at higher speed regimes. Compiling all together, increasing the concentration of the biodiesel blends obviously reduced the performance values and however, there was a great advantage in terms of the emission magnitudes irrespective of the engine operating conditions.


Assuntos
Poluentes Ambientais , Nanotubos de Carbono , Animais , Biocombustíveis , Monóxido de Carbono/análise , Galinhas , Gasolina , Hidrogênio , Emissões de Veículos , Gorduras
18.
Heliyon ; 8(12): e12393, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36582710

RESUMO

Understanding the determinants of fiscal deficits is justified by the fact that persistent deficits rapidly lead to the accumulation of public debt. Therefore, the aim of this paper is to analyze the factors that explained the fiscal deficits of Spanish municipalities in the period 2011-2020. The deficit at the municipal level for Spain is explained by considering several determinants covering socioeconomic and political dimensions, such as GDP per capita, unemployment rate, population, political participation, political sign of the ruling party or political force, among others. The method of moments quantile regression (MMQ) and mean group (MG) estimator are applied for the overall sample and for each group of municipalities. In addition, the causality between the deficit and the explanatory variables is analyzed using the Juodis et al. (2021) test. It is found that economic growth only has a long-term beneficial effect on the deficit as it reduces the deficit at all quantile levels except at the 10% quantile. Unemployment increases the deficit in both the short and long run. Political participation and right-wing political parties contribute to the growth of the deficit in the higher quantiles. To reduce the budget deficit, the analysis shows that unemployment should be reduced and economic growth should be boosted. The results are robust to those based on mean group estimators. With this paper, we contribute to the scarce literature on deficit determinants by analyzing the determinants for Spanish municipalities. Furthermore, our findings have important implications for politicians, citizens and stakeholders.

19.
Front Psychiatry ; 13: 869337, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35782431

RESUMO

Current research examines the impact of academic and familial stress on students' depression levels and the subsequent impact on their academic performance based on Lazarus' cognitive appraisal theory of stress. The non-probability convenience sampling technique has been used to collect data from undergraduate and postgraduate students using a modified questionnaire with a five-point Likert scale. This study used the SEM method to examine the link between stress, depression, and academic performance. It was confirmed that academic and family stress leads to depression among students, negatively affecting their academic performance and learning outcomes. This research provides valuable information to parents, educators, and other stakeholders concerned about their childrens' education and performance.

20.
Front Public Health ; 10: 893845, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35774570

RESUMO

Poor mental health is a growing concern among young people during the coronavirus disease 2019 (COVID-19) pandemic. The aim of this study was to assess the associations of Internet addiction with depressive symptoms, anxiety symptoms, and stress in higher education students during the COVID-19 pandemic, as well as to examine these mental health problems in the context of study-related characteristics. The research sample consisted of 3,099 participants from the Czech Republic (CZ: 1,422) and Slovak Republic (SK: 1,677). The Internet Addiction Test (IAT), the Generalized Anxiety Disorder (GAD-7) scale, the Patient Health Questionnaire for depressive symptoms (PHQ-9), and the Perceived Stress Scale (PSS) were used to measure mental health problems. The analyses also included demographic data (gender and age) and study-related characteristics (form of study, degree of study, field of study, distance between college and home, and housing during the semester). Based on the results of frequency and descriptive analyses, the prevalence of mental health problems was high. The most serious levels of Internet addiction (IAT cut-off point ≥ 50), to which attention should be paid, were found in 3.5% of Czech and 6.2% of Slovak students. Using the standard cut-off point of GAD-7 ≥ 10, 14.1% of Czech and 11.6% of Slovak students were identified with anxiety symptoms. Regarding the PHQ-9 with the cut-off point ≥ 10, 23.4% of Czech and 19.1% of Slovak students had depressive symptoms, which should be addressed. Using the PSS cut-off point ≥ 27, 12.9% of Czech students and 9.1% of Slovak students perceived high stress. The quantile regression analysis showed that Internet addiction was positively associated with anxiety symptoms, depressive symptoms, and stress in all of the analyzed cases (p-value < 0.001). In terms of study-related characteristics, the binomial logistic regression analysis revealed that risk factors for mental health problems in Czech and Slovak students were mainly full-time form of study and living away from home during the semester. Internet addiction, anxiety symptoms, depressive symptoms, and stress are issues that require increased attention, and professionals and policy-makers should implement interventions to effectively prevent and help students with psychological problems.


Assuntos
COVID-19 , Pandemias , Adolescente , Ansiedade/epidemiologia , Transtornos de Ansiedade/epidemiologia , COVID-19/epidemiologia , Depressão/epidemiologia , Humanos , Transtorno de Adição à Internet/epidemiologia , Estresse Psicológico/epidemiologia , Estudantes/psicologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...