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1.
Sci Rep ; 14(1): 7902, 2024 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-38570524

RESUMO

The spatial movement of the human population from one region to another and the existence of super-spreaders are the main factors that enhanced the disease incidence. Super-spreaders refer to the individuals having transmitting ability to multiple pathogens. In this article, an epidemic model with spatial and temporal effects is formulated to analyze the impact of some preventing measures of COVID-19. The model is developed using six nonlinear partial differential equations. The infectious individuals are sub-divided into symptomatic, asymptomatic and super-spreader classes. In this study, we focused on the rigorous qualitative analysis of the reaction-diffusion model. The fundamental mathematical properties of the proposed COVID-19 epidemic model such as boundedness, positivity, and invariant region of the problem solution are derived, which ensure the validity of the proposed model. The model equilibria and its stability analysis for both local and global cases have been presented. The normalized sensitivity analysis of the model is carried out in order to observe the crucial factors in the transmission of infection. Furthermore, an efficient numerical scheme is applied to solve the proposed model and detailed simulation are performed. Based on the graphical observation, diffusion in the context of confined public gatherings is observed to significantly inhibit the spread of infection when compared to the absence of diffusion. This is especially important in scenarios where super-spreaders may play a major role in transmission. The impact of some non-pharmaceutical interventions are illustrated graphically with and without diffusion. We believe that the present investigation will be beneficial in understanding the complex dynamics and control of COVID-19 under various non-pharmaceutical interventions.


Assuntos
COVID-19 , Epidemias , Humanos , COVID-19/epidemiologia , Dinâmica não Linear , Simulação por Computador , Difusão
2.
Artigo em Inglês | MEDLINE | ID: mdl-38623980

RESUMO

AIM AND OBJECTIVE: The aim of this study was to prepare polyvinyl alcohol/acrylic acid (PVA/AA) hydrogels for the controlled release of diclofenac sodium and to develop PVA/AA hydrogels as controlled release carriers to overcome not only the side effects of diclofenac sodium but also sustain its release for an extended period. BACKGROUND: Diclofenac sodium is employed for relieving pain and fever. The half-life of diclofenac sodium is very short (1-2 h). Hence, multiple intakes of diclofenac sodium are required to maintain a constant pharmacological action. Multiple GI adverse effects are produced as a result of diclofenac sodium intake. METHOD: A free radical polymerization technique was used for crosslinking PVA with AA in the presence of APS. EGDMA was used as a cross-linker. FTIR and XRD confirmed the preparation and loading of the drug by prepared hydrogels. An increase in the thermal stability of PVA was shown by TGA and DSC analysis. Surface morphology was investigated by SEM. Similarly, water penetration and drug loading were demonstrated by porosity and drug loading studies. The pH-sensitive nature of PVA/AA hydrogels was investigated at different pH values by swelling and drug release studies. RESULTS: The development and drug loading of PVA/AA hydrogels were confirmed by FTIR and XRD analysis. TGA and DSC indicated high thermal stability of prepared hydrogels as compared to unreacted PVA. SEM indicated a hard and compact network of developed hydrogels. The swelling and drug release studies indicated maximum swelling and drug release at high pH as compared to low pH values, indicating the pH-sensitive nature of prepared hydrogels. Moreover, we demonstrated that drug release was sustained for a prolonged time in a controlled pattern by prepared hydrogels by comparing the drug release of the developed hydrogels with the commercial product Cataflam. CONCLUSION: The results indicated that prepared PVA/AA hydrogels can be used as an alternative approach for the controlled delivery of diclofenac sodium.

3.
J Fluoresc ; 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38538961

RESUMO

Dye solubilization in microemulsion based on Cetyltrimethylammonium bromide (CTAB) and its modified forms (counter-anions based upon Zn2+, Cu2+ and Fe3+) is comparatively innovative and not explored in existing literature. Here, surfactant with modified counterions (SMCs) were used to study the effects of metal chlorides (ZnCl2, CuCl2 and FeCl3) modifications on the comparative solubilization of Rhodamine-B (RB) by Cetyltrimethylammonium bromide (CTAB) and its modified forms. The solubility of RB in different microemulsions were studied using UV-Visible spectroscopy and phase diagrams of CTAB with modified counter ions CTA+[ZnCl2.Br]- named as CZN-1, CTA+[CuCl2.Br]- named as CCU-1 and CTA+[FeCl3.Br]- named as CFE-1 based upon surfactant with modified counter ions (SMCs). Four different points in microemulsion region of phase diagram were selected with different percentage composition of Smix (surfactant and co-surfactant), oil and RB (taken as water component). The interaction of RB, CCU-1, CFE-1 and CZN-1 within microemulsion environment were studied using Fluorescence spectroscopy. Emission spectra of RB in CCU-1 and CFE-1 based microemulsion confirmed that RB formed complexes with Cu and Fe ions. It was also found that RB was less soluble in CTAB based microemulsion as compared to microemulsions based on SMCs. This novel research study will expose new path for future research work related to microemulsion.

4.
J Biomol Struct Dyn ; : 1-20, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38109166

RESUMO

Cellular infections are central to the etiology of various diseases, notably cancer and malaria. Counteracting cellular oxidative stress via the inhibition of glutathione reductase (GR) has emerged as a promising therapeutic strategy. Houttuynia cordata, a medicinal plant known for its potent antioxidant properties, has been the focus of our investigation. In this study, we conducted comprehensive in silico analyses involving the phytochemical constituents of H. cordata to identify potential natural GR inhibitors. Our methodological approach encompassed multiple in silico techniques, including molecular docking, molecular dynamics simulations, MMPBSA analysis, and dynamic cross-correlation analysis. Out of 13 docked phytochemicals, Quercetin, Quercitrin, and Sesamin emerged as particularly noteworthy due to their exceptional binding affinities for GR. Notably, our investigation demonstrated that Quercetin and Sesamin exhibited promising outcomes compared to the well-established pharmaceutical agent N-acetylcysteine (NAC). Molecular dynamics analyses provided insights into the ability of these phytochemicals to induce structural compaction and stabilization of the GR protein, as evidenced by changes in radius of gyration and solvent-accessible surface area. Moreover, MMPBSA analysis highlighted the crucial roles of specific residues, namely Gly27, Gly28, Ser51, His52, and Val61, in mediating essential interactions with these phytochemicals. Furthermore, an assessment of Absorption, Distribution, Metabolism, Excretion, and Toxicity (ADME-Tox) profiles underscored the favourable drug-like attributes of these phytochemicals. Thus, the current findings underscore the immense potential of Houttuynia cordata phytochemicals as potent antioxidants with the capacity to combat a spectrum of maladies, including malaria and cancer. This study not only unveils novel therapeutic avenues but also underscores the distinctive outcomes and paramount significance of harnessing H. cordata phytochemicals for their efficacious antioxidant properties.Communicated by Ramaswamy H. Sarma.

5.
Environ Sci Pollut Res Int ; 30(54): 115322-115336, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37884723

RESUMO

China's critical reliance on well-crafted public policies, coupled with the effective execution of central government directives at the local level, drives the achievement of the "dual carbon" goal including the peaking of CO2 emissions and attaining carbon neutrality. Therefore, examining policy records can unveil the holistic strategy for attaining carbon neutrality during the period of peak CO2 emissions; at the same time, it can also highlight the potential obstacles in policy implementation. In this study, we adopt a policy instruments perspective to investigate data related to policies addressing peak CO2 emissions across 29 provincial administrative regions in China. We apply Nvivo12 software to conduct a quantitative literature assessment and content analysis to establish a theoretical framework for the policy process. This framework encompasses dimensions such as political feasibility, regional coordination, attributes of low-carbon initiatives, and policy refinement. Subsequently, we employ the model to carry out a retrospective analysis of policy documents pertaining to peak CO2 emissions in China. Our research findings underscore the pivotal role of political feasibility in shaping policy effectiveness, while also highlighting the facilitative influence of regional coordination, shedding light on the essential synergy between provinces and cities in achieving emissions reduction goals. Similarly, the estimated results highlight the motivating impact of specific attributes within low-carbon initiatives. Moreover, policy enhancements are identified as a critical driver in advancing the path toward carbon neutrality. Consequently, to achieve the objective of carbon neutrality, it is imperative for every province and city to sequentially reach the peak of CO2 emissions. Our research offers a comprehensive "China strategy," providing valuable insights to guide future policy formulation and accelerate progress toward sustainable environmental objectives.


Assuntos
Dióxido de Carbono , Política Pública , Estudos Retrospectivos , Carbono , China , Desenvolvimento Econômico
6.
Adv Sci (Weinh) ; 10(35): e2302858, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37890452

RESUMO

Soft transparent electrodes (TEs) have received tremendous interest from academia and industry due to the rapid development of lightweight, transparent soft electronics. Metallic micro-nano networks (MMNNs) are a class of promising soft TEs that exhibit excellent optical and electrical properties, including low sheet resistance and high optical transmittance, as well as superior mechanical properties such as softness, robustness, and desirable stability. They are genuinely interesting alternatives to conventional conductive metal oxides, which are expensive to fabricate and have limited flexibility on soft surfaces. This review summarizes state-of-the-art research developments in MMNN-based soft TEs in terms of performance specifications, fabrication methods, and application areas. The review describes the implementation of MMNN-based soft TEs in optoelectronics, bioelectronics, tactile sensors, energy storage devices, and other applications. Finally, it presents a perspective on the technical difficulties and potential future possibilities for MMNN-based TE development.

7.
Environ Sci Pollut Res Int ; 30(47): 104697-104712, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37707736

RESUMO

This study employs panel data from 1990 to 2020 for the G-7 countries (Canada, France, Germany, Italy, Japan, the UK, and the USA) and employs the examination of heterogeneous slope coefficients and cross-sectional dependence tests as preliminary steps before conducting cointegration analysis and second-generation unit-root tests. This study employs the method of movement quantile regression (MMQR) to analyze long-run and short-run relationships. The findings from the MMQR model indicate that economic growth and imports have a negative impact on consumption-based CO2 (CCO2) emissions, which worsens at higher quantiles. On the other hand, exports, energy efficiency, and renewable energy output (REO) have a positive effect on mitigating CCO2 emissions, with this effect becoming more pronounced at higher quantiles. Furthermore, the robustness of the results was confirmed through rigorous checks using quantile regression with optimized Markov Chain Monte Carlo techniques, which is a reliable non-parametric approach. These checks consistently demonstrated a significant impact on CCO2 emissions, thus validating the findings obtained from MMQR. Based on the outcomes, this study recommends that each G-7 nations should make efforts to regulate their CCO2 emissions by adopting measures that foster ecological equilibrium. Moreover, fostering export-driven sectors, exploring innovative strategies for REO, and improving energy efficiency are crucial measures for effectively tackling CCO2 emissions within the G-7 countries. The study highlights that renewable energy output (REO) and energy efficiency effectively mitigate CCO2 emissions at higher quantiles, suggesting the importance of policy measures supporting their development. Additionally, policies targeting import reduction, export promotion, and carbon pricing mechanisms emerge as strategies to curb emissions and foster sustainable development.


Assuntos
Dióxido de Carbono , Carbono , Estudos Transversais , Desenvolvimento Econômico , Análise de Regressão , Energia Renovável
8.
Cureus ; 15(8): e44048, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37746401

RESUMO

INTRODUCTION: This study was conducted to clinically compare a commercially available combination of 70:30 nanocrystalline hydroxyapatite (HA) and beta tricalcium phosphate (ßTCP) along with platelet-rich fibrin (PRF) with demineralized freeze-dried bone (DFDB) grafts along with PRF in small maxillofacial osseous defects. MATERIALS AND METHODS: Thirty patients with one osseous defect were randomly distributed into two groups of 15 each: Group A and Group B. Group A patients received HA+ßTCP+PRF while Group B received DFDB + PRF. Postoperative pain, swelling, wound dehiscence, and the presence or absence of infection were evaluated at various intervals up to seven postop days and compared between the two groups and within either group. A technetium 99m methylene diphosphonate (MDP 99mTc) scan was also done for a representative patient of either group at the end of three months to evaluate the fate of the graft. RESULTS: We found no significant difference between the two groups for any of our parameters. Significant improvements were noted for pain and swelling within either group at various intervals. The MDP 99mTc scan showed increased tracer uptake for the representing patient of either group. CONCLUSIONS: HA+ßTCP is more inexpensive than DFDB and more readily available and has no host incompatibility or infection potential, resulting in similar clinical postoperative states as DFDB when either is used with PRF.

9.
Neuropharmacology ; 240: 109681, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37611823

RESUMO

Nicotine vapor consumption via electronic nicotine delivery systems has increased over the last decade. While prior work has shed light on the health effects of nicotine vapor inhalation, its unique effects on the brain and behavior have not been thoroughly explored. In this study we assessed markers of withdrawal following 14 days of nicotine vapor exposure. For Experiment 1, 21 adult male rats were exposed to ambient air or 6, 12, or 24 mg/mL nicotine vapor for 14 consecutive days. Following exposure on day 14, rats were injected with the nicotinic receptor antagonist mecamylamine (3.0 mg/mL) and assessed for somatic withdrawal signs and anxiety-like behavior in the elevated plus maze. For Experiment 2, 12 adult male rats were tested for intracranial self-stimulation (ICSS) immediately following exposure to vehicle vapor (50%/50%, vegetable glycerin/propylene glycol) or 24 mg/mL nicotine vapor, for 14 consecutive days. ICSS behavior was assessed for an additional 14 days, following cessation of repeated vapor exposure. Results reveal that rats with repeated nicotine vapor exposure display an increase in behavioral indicators of withdrawal following injection of mecamylamine (precipitated withdrawal). Additionally, increases in ICSS stimulation thresholds, indicative of reduced brain reward sensitivity, persist following cessation of repeated nicotine vapor exposure (spontaneous withdrawal). These data suggest that repeated e-cigarette use leads to nicotine dependence and withdrawal that affects behavior and brain reward function. Further characterization of the health effects of nicotine vapor is necessary to improve treatment strategies for nicotine use disorder and public health policies related to novel nicotine delivery systems.

10.
Glob Cardiol Sci Pract ; 2023(3): e202317, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37575289

RESUMO

BACKGROUND: The Fontan procedure is the final stage of a three-stage palliation process in patients born with a univentricular heart as part of hypoplastic left heart syndrome (HLHS) or other pathologies with a univentricular heart. As essential as this procedure has proven to be for such cases, the Fontan physiology diminishes cardiac output and expands systemic venous pressure, which then leads to venous congestion that can be complicated by protein-losing enteropathy (PLE). This retrospective study aimed to identify the predictors of such complications in all patients who underwent completion of the Fontan procedure at our center (Sheikh Khalifa Medical City/SKMC) in the past eight years. METHODS: This study examined the medical records of patients who underwent completion of Fontan repair at our center since the inauguration of the cardiac surgery program of SKMC in the United Arab Emirates (UAE) - 01 Jan 2012 to 31 Dec 2020. Exclusion criteria included the absence of any of the undermentioned data in patient files. Patients were divided into two groups: those who developed PLE and those who did not. For each group, the following data were collected: demographics data (current age and age at completion of Fontan), clinical and laboratory data (oxygen saturation, serum albumin), echocardiographic data (classification of original cardiac diagnosis, degree of atrio-ventricular valve regurgitation, ventricular functions), hemodynamic data (mean pressures of superior vena cava and pulmonary arteries before Fontan completion), operative data (type of initial palliation, type of Fontan, presence of fenestrations and its size) and the need for any cardiac intervention prior to Fontan completion, such as atrio-ventricular valve repair, peripheral pulmonary stenting and arch balloon dilatation. RESULTS: Of the 48 included patients,13 (25%) developed PLE. Multivariate regression analysis proved that the best predictors of PLE were superior vena cava mean pressure (P = 0.012) and the degree of atrio-ventricular valve regurgitation (P = 0.013). An oxygen saturation <83% prior to Fontan completion was 92% sensitive in predicting PLE after Fontan completion. CONCLUSION: This is a single-center study of the predictors of PLE after Fontan procedure and, as expected from similar studies, SVC pressure higher than 11 mmHg and moderate-to-severe atrio-ventricular valve regurgitation were predictors of Fontan failure. The higher prevalence of PLE in our cohort, as well as lower cut-offs of SVC pressure that can predict complications, may be related to the predominance of hypoplastic left heart in the operated patients, which has been the main referral center for cardiac surgeries in UAE in the last decade.

11.
Gels ; 9(8)2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37623095

RESUMO

Smart and intelligent xanthan gum/pluronic F-127 hydrogels were fabricated for the controlled delivery of atomoxetine HCl. Different parameters such as DSC, TGA, FTIR, XRD, SEM, drug loading, porosity, swelling index, drug release, and kinetics modeling were appraised for the prepared matrices of hydrogels. FTIR confirmed the successful synthesis of the hydrogel, while TGA and DSC analysis indicated that the thermal stability of the reagents was improved after the polymerization technique. SEM revealed the hard surface of the hydrogel, while XRD indicated a reduction in crystallinity of the reagents. High gel fraction was achieved with high incorporated contents of the polymers and the monomer. An increase in porosity, drug loading, swelling, and drug release was observed with the increase in the concentrations of xanthan gum and acrylic acid, whereas Pluronic F-127 showed the opposite effect. A negligible swelling index was shown at pH 1.2 and 4.6 while greater swelling was observed at pH 7.4, indicating a pH-responsive nature of the designed hydrogels. Furthermore, a higher drug release was found at pH 7.4 compared to pH 1.2 and 4.6, respectively. The first kinetics order was followed by the prepared hydrogel formulations. Thus, it is signified from the discussion that smart xanthan gum/pluronic F-127 hydrogels have the potential to control the release of the atomoxetine HCl in the colon for an extended period of time.

12.
Nanotechnology ; 34(48)2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37625394

RESUMO

The customization of hybrid nanofluids to achieve a particular and controlled growth rate of thermal transport is done to meet the needs of applications in heating and cooling systems, aerospace and automotive industries, etc. Due to the extensive applications, the aim of the current paper is to derive a numerical solution to a wall jet flow problem through a stretching surface. To study the flow problem, authors have considered a non-Newtonian Eyring-Powell hybrid nanofluid with water and CoFe2O4and TiO2nanoparticles. Furthermore, the impact of a magnetic field and irregular heat sink/source are studied. To comply with the applications of the wall jet flow, the authors have presented the numerical solution for two cases; with and without a magnetic field. The numerical solution is derived with a similarity transformation and MATLAB-based bvp4c solver. The value of skin friction for wall jet flow at the surface decreases by more than 50% when the magnetic fieldMA=0.2is present. The stream function value is higher for the wall jet flow without the magnetic field. The temperature of the flow rises with the dominant strength of the heat source parameters. The results of this investigation will be beneficial to various applications that utilize the applications of a wall jet, such as in car defrosters, spray paint drying for vehicles or houses, cooling structures for the CPU of high-processor laptops, sluice gate flows, and cooling jets over turbo-machinery components, etc.

13.
Environ Sci Pollut Res Int ; 30(42): 96147-96162, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37566332

RESUMO

The prime focus of the present investigation delves into the linkage between digital financial services and energy intensity within the geographic confines of China, utilizing provincial-level panel data spanning from 2011 to 2021. Digital finance has rapidly developed due to changes in information technology, and its role in achieving green transformation, reducing energy consumption, and lowering energy intensity in Chinese society is critical. By conducting empirical analysis utilizing diverse models, we have tested our hypotheses and found that digital finance's improvement can contribute to the reduction in energy intensity at the regional level while still considering endogeneity concerns. This effect is mediated by the promotion of technological innovation and the facilitation of green development in industries. Digital finance's impact on energy intensity is contingent upon resource endowments, such as the level of traditional financial development and the degree of information. Moreover, digital finance's adverse impact on energy intensity becomes more pronounced beyond certain threshold values. However, digital finance can increase energy intensity in neighboring regions through spatial spillover effects. Drawing upon our findings, we recommend bolstering the development of digital finance, augmenting the capability for autonomous innovation, and devising specialized strategies for digital finance advancement to fully harness the potential of digital finance in curbing energy intensity. This study interprets the value of digital finance from the new perspective of energy intensity. By exploring the internal links between digital finance and energy intensity, the study enriches the research results on the impact of digital finance on energy intensity.


Assuntos
Indústrias , Tecnologia da Informação , Causalidade , China , Desenvolvimento Econômico
14.
ACS Omega ; 8(26): 23991-24002, 2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37426260

RESUMO

The objective of this study is to design a polymeric network of nanogels for sustained release of caffeine. Therefore, alginate-based nanogels were fabricated by a free-radical polymerization technique for the sustained delivery of caffeine. Polymer alginate was crosslinked with monomer 2-acrylamido-2-methylpropanesulfonic acid by crosslinker N',N'-methylene bisacrylamide. The prepared nanogels were subjected to sol-gel fraction, polymer volume fraction, swelling, drug loading, and drug release studies. A high gel fraction was seen with the increasing feed ratio of polymer, monomer, and crosslinker. Greater swelling and drug release were observed at pH 4.6 and 7.4 as compared to pH 1.2 due to the deprotonation and protonation of functional groups of alginate and 2-acrylamido-2-methylpropanesulfonic acid. An increase was observed in swelling, loading, and release of the drug with the incorporation of a high feed ratio of polymer and monomer, while a reduction was seen with the increase in crosslinker feed ratio. Similarly, an HET-CAM test was used to evaluate the safety of the prepared nanogels, which showed that the prepared nanogels have no toxic effect on the chorioallantoic membrane of fertilized chicken eggs. Similarly, different characterizations techniques such as FTIR, DSC, SEM, and particle size analysis were carried out to determine the development, thermal stability, surface morphology, and particle size of the synthesized nanogels, respectively. Thus, we can conclude that the prepared nanogels can be used as a suitable agent for the sustained release of caffeine.

15.
RSC Adv ; 13(30): 21008-21020, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37441046

RESUMO

Araldite LY5052 epoxy resin and Aradur HY5052 hardener were used in a ratio of 100 : 38 to produce composite coatings containing 0.05 proportion of functionalized SiO2. Coating samples were cured at curing temperatures of 60, 80, 100, 120, and 140 °C. The results of Fourier Transform Infrared Spectroscopy (FTIR) verified that silica particles were successfully functionalized with methyltrimethoxysilane (MTMS)/3-aminopropyl-triethoxysilane (APTES). The epoxide and Si-O bond peaks in the EHS100 coating were present due to the effective incorporation of functionalized silica (FSiO2) particles in the polymeric matrix (epoxy resin). The surface morphology of the bare aluminium alloy AA7075 and EHS100 coating was investigated by Field Emission Scanning Electron Microscopy (FE-SEM). Additionally, corrosion analysis was conducted at room temperature using an electrolytic solution of artificial seawater, prepared according to ASTM standard D1141-98. Charge transfer resistance (Rct) was shown to increase by 86.43, 92.15, 94.76, 90.65, and 83.96% for EHS60, EHS80, EHS100, EHS120, and EHS140 in comparison to bare AA7075 substrate using electrochemical impedance spectroscopy (EIS) examination. Furthermore, potentiodynamic polarization (PDP) measurements were carried out to determine the corrosion rates, which demonstrated a drop of 55.98, 98.96, 99.37, 98.33, and 50.39% for EHS60, EHS80, EHS100, EHS120, and EHS140, as compared to the bare AA7075 sample. The highest charge transfer resistance (29.77 kΩ) and lowest corrosion rate (0.00078 mm per year) were recorded for EHS100, which reveals that the EHS100 coating has the best anti-corrosion performance and provides the maximum corrosion protection for the aluminium alloy AA7075 substrate.

16.
Sci Rep ; 13(1): 12108, 2023 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-37495630

RESUMO

In this paper, a new spatio-temporal model is formulated to study the spread of coronavirus infection (COVID-19) in a spatially heterogeneous environment with the impact of vaccination. Initially, a detailed qualitative analysis of the spatio-temporal model is presented. The existence, uniqueness, positivity, and boundedness of the model solution are investigated. Local asymptotical stability of the diffusive COVID-19 model at steady state is carried out using well-known criteria. Moreover, a suitable nonlinear Lyapunov functional is constructed for the global asymptotical stability of the spatio-temporal model. Further, the model is solved numerically based on uniform and non-uniform initial conditions. Two different numerical schemes named: finite difference operator-splitting and mesh-free operator-splitting based on multi-quadratic radial basis functions are implemented in the numerical study. The impact of diffusion as well as some pharmaceutical and non-pharmaceutical control measures, i.e., reducing an effective contact causing infection transmission, vaccination rate and vaccine waning rate on the disease dynamics is presented in a spatially heterogeneous environment. Furthermore, the impact of the  aforementioned interventions is investigated with and without diffusion on the incidence of disease. The simulation results conclude that the random motion of individuals has a significant impact on the disease dynamics and helps in setting a better control strategy for disease eradication.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Simulação por Computador , Difusão , Erradicação de Doenças
17.
Environ Sci Pollut Res Int ; 30(37): 87300-87313, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37422562

RESUMO

The significance of accurately assessing the influence of digital economy growth upon reducing emission of carbon in the context of worldwide climate governance cannot be overstated. This is crucial in encouraging low-carbon economic advancement at national level, achieving carbon peak and neutrality as soon as possible, and creating a shared future for humanity. A mediating effect model is established using cross-country panel data from 100 countries, ranging from 1990 to 2019, to assess the influence of digital economy development upon emission of carbon and to explore its underlying mechanism. The study found that: the growth of national emission of carbon can be considerably suppressed by digital economy development, and the reduction of emissions is positively associated to each country's level of economic advancement. Digital economy growth influences regional emission of carbon via intermediary channels like energy structure and efficiency, with energy intensity having a particularly noticeable intermediary impact. The inhibitory influence of digital economy development upon emission of carbon differs among countries with different levels of income, and improvements in energy structure and efficiency can precede to energy savings and emission reduction in both middle- and high-income countries. The above findings offer policy guidance for harmoniously advancing the growth of digital economy and climate management, hastening the low-carbon transformation of national economies, and implementing China's carbon peaking initiative.


Assuntos
Fenômenos Bioquímicos , Conservação de Recursos Energéticos , Desenvolvimento Econômico , Carbono , Clima , China , Dióxido de Carbono
18.
Cell Rep ; 42(8): 112856, 2023 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-37481717

RESUMO

To identify addiction genes, we evaluate intravenous self-administration of cocaine or saline in 84 inbred and recombinant inbred mouse strains over 10 days. We integrate the behavior data with brain RNA-seq data from 41 strains. The self-administration of cocaine and that of saline are genetically distinct. We maximize power to map loci for cocaine intake by using a linear mixed model to account for this longitudinal phenotype while correcting for population structure. A total of 15 unique significant loci are identified in the genome-wide association study. A transcriptome-wide association study highlights the Trpv2 ion channel as a key locus for cocaine self-administration as well as identifying 17 additional genes, including Arhgef26, Slc18b1, and Slco5a1. We find numerous instances where alternate splice site selection or RNA editing altered transcript abundance. Our work emphasizes the importance of Trpv2, an ionotropic cannabinoid receptor, for the response to cocaine.


Assuntos
Transtornos Relacionados ao Uso de Cocaína , Cocaína , Camundongos , Animais , Cocaína/farmacologia , Estudo de Associação Genômica Ampla , Encéfalo , Administração Intravenosa , Camundongos Endogâmicos C57BL
19.
SICOT J ; 9: 22, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37470755

RESUMO

OBJECTIVE: To determine the frequency, clinical presentation, and etiological factors of cauda equina syndrome (CES). MATERIALS AND METHOD: This retrospective study was done on 256 participants, and aimed to analyze the frequency and patterns of clinical presentation in suspected cases of CES. The inclusion criteria included participants aged 18 or older with medical records available for review and having red-flagged symptoms for CES. The study collected information on various factors such as age, gender, confirmation of CES on MRI, neurological deficits, etiological factors, duration of symptoms, and more. The data collected was analyzed using descriptive statistics and logistic regression to identify significant variables between MRI-proven CES and suspected CES. RESULTS: The mean age was 58.05 ± 19.26 years, with 151 females (58.98%) and 105 males (41.02%). The majority (50.78%) had a neurological deficit, while other symptoms included difficulty initiating micturition or impaired sensation of urinary flow (17.58%), loss of sensation of rectal fullness (3.12%), urinary or faecal incontinence (35.16%), bilateral sciatica (21.88%), neurological symptoms in the lower limbs (25.00%), anaesthesia or any leg weakness (24.22%), and bilateral sciatica as the predominant symptom (21.88%). Symptoms were chronic in 47.27% and acute in 21.88%. The odds of MRI-proven CES increase by 3% per year of age. Neurological deficit was strongly associated with MRI-proven CES (OR = 14.97), while loss of sensation of rectal fullness increased the odds by 10-fold (OR = 10.62). CONCLUSION: CES can present with various symptoms, including the bilateral neurological deficit, urinary and faecal incontinence, and bilateral sciatica, with age, severe bilateral neurological deficit, and loss of sensation of rectal fullness being associated with MRI-proven CES. Early diagnosis and treatment are crucial for better outcomes.

20.
Plants (Basel) ; 12(12)2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37376010

RESUMO

Plant-parasitic nematodes (PPNs) pose a threat to global food security in both the developed and developing worlds. PPNs cause crop losses worth a total of more than USD 150 billion worldwide. The sedentary root-knot nematodes (RKNs) also cause severe damage to various agricultural crops and establish compatible relationships with a broad range of host plants. This review aims to provide a broad overview of the strategies used to identify the morpho-physiological and molecular events that occur during RKN parasitism. It describes the most current developments in the transcriptomic, proteomic, and metabolomic strategies of nematodes, which are important for understanding compatible interactions of plants and nematodes, and several strategies for enhancing plant resistance against RKNs. We will highlight recent rapid advances in molecular strategies, such as gene-silencing technologies, RNA interference (RNAi), and small interfering RNA (siRNA) effector proteins, that are leading to considerable progress in understanding the mechanism of plant-nematode interactions. We also take into account genetic engineering strategies, such as targeted genome editing techniques, the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR associated protein 9 (Cas9) (CRISPR/Cas-9) system, and quantitative trait loci (QTL), to enhance the resistance of plants against nematodes.

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