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Will cultural diversity block the process of urbanization?—Empirical Study from the perspective of dialect
Get PDFBased on the data samples of 276 cities at prefecture level and above in China from 2000 to 2012, using dialect diversity as a proxy to measure cultural diversity, using random effect model, system generalized moment estimation, two-stage least square method and other methods, this paper conducted an empirical investigation on the impact of cultural diversity on China's urbanization for the first time. It is found that dialect diversity has a significant negative impact on urbanization rate; considering the possibility of missing variables, the influence of dialect diversity on urbanization rate is still significantly negative; after using the historical immigration as the instrumental variable of dialect diversity, this negative influence still exists, but the degree of influence has decreased. Therefore, the cultural variables represented by dialects are an important factor affecting the process of urbanization
The use of R code for modeling and simulation of 2-D contaminant migration through a soil for the pulse source
Get PDFIn this study, based on an existing analytical solution for the two-dimensional transport of contaminants in a saturated soil layer, for the pulse source, the R program code was developed. The simulation is used to obtain the profiles of contaminant concentration, for a steady groundwater velocity, as a function of distance from the source and time. The problem is analytically solved by leveraging the similarity between the Gaussian (normal) distribution and contaminant concentration distribution, the development of the analytical model (i.e., solution of partial differential equation) by using this similarity is explained step by step since it may be of interest to researchers. Contaminant propagation is modeled using R software, which helps to understand how contaminants migrate through a saturated soil layer. This approach aids in comprehending the mechanisms and spatial dynamics of contaminant dispersion, facilitating the prediction and management of soil and groundwater contamination. The provided R code can be altered for different parameters and time intervals
Urban political ecology of wetland resources in Bamenda town, north west region, Cameroon
Get PDFWetlands are unique ecosystems that play a critical role in the preservation of biodiversity and the provision of ecological services. This work on the Urban Political Ecology (UPE) of wetland resources in Bamenda has as objective to examine stakeholder participation and power relations resulting from the exploitation and management of wetlands. It looks at the challenges of wetland conservation in context of rapid urbanization. Using a mixed methods approach and the specific case of Bamenda III municipality, data was collected from secondary and primary sources. A household questionnaire survey was conducted with 150 households while 12 in-depth interviews were carried out with key informants. Data was analyzed quantitatively and qualitative and results were critiqued using the lens of UPE. Results show that between 1988 and 2022, wetlands reduction was more than 6.78%. This reduction is caused by agriculture, land reclamation and expansion of urban infrastructure. As such, Conservation has become a huge challenge due to overlapping responsibilities and an ambiguous regulatory system that focuses on biodiversity conservation only. This has created conflictual power relations and a complexified management system. The UPE approach has revealed that the consideration of socio-economic and cultural ecosystem services in wetland management is key to sustainability
How does digital transformation influence green governance? A synthesis of the literature
Get PDFPropose: This paper focuses on helping companies solve the pressure brought by the current digital trend and environmental ecological challenges and achieve the strategic goal of sustainable development. Methods: In this paper, the literature review method is used to collect the relevant literature of the Web of Science (WOS) database 2014–2015 and explore the natural advantages of digital transformation (DT) in the field of green governance. In addition, VOSviewer is used for literature metrology to generate a visual map in order to visually present the current research hotspots. Results: This study shows that DT has three advantages in the field of green governance. Firstly, DT can significantly affect green governance. Secondly, DT can significantly affect green innovation. Thirdly, DT can significantly affect Environment, Social, and Governance (ESG) performance. Practical implications: This study reviews the relevant literature on DT and green governance and excavates the influence of DT in the field of green governance. On the one hand, this study enriches the dual research perspectives of DT and green governance, fills the gap in the study of DT green governance and the level of new green governance, and has important theoretical significance. On the other hand, it is of great practical significance to explore the impact of DT on green governance and provide an important reference for companies to build a new governance paradigm in the digital era
An iterative method for robust solutions to nonlinear Volterra integral equations: Stability, convergence, and practical applications
Get PDFThe paper introduces an iterative method for solving nonlinear Volterra integral equations and analyzes its convergence, stability, and application through examples. It expresses the general nonlinear Volterra integral equation as a series and decomposes the nonlinear operator to derive a recursive formula for the proposed iterative method. The method ensures absolute and uniform convergence, with stability analysis conducted to ensure bounded errors in the presence of perturbations. Convergence analysis utilizes the Lipschitz condition, demonstrating the uniform convergence of the solution series. Illustrative examples, including power nonlinearity and trigonometric functions, validate the stability and convergence of the method. Through graphical representations, convergence analyses for specific integral equations demonstrate the method’s effectiveness and applicability in solving diverse nonlinear integral equations. Overall, the paper contributes a robust iterative method with insights into its stability and convergence properties, supported by practical examples
On matrix strong Diophantine 27-Tuples and matrix elliptic curves
Get PDFWe introduce an algorithm which allows us to prove that there exists an infinite number of matrix strong Diophantine -tuples. We show that Diophantine quadruples generate matrix elliptic (or hyperelliptic) curves which have each matrix points
Baicalein Exerts Anti-Tumor Effects on Nasopharyngeal Carcinoma by Mediating the FOXO-1/NF-κB Signaling Pathway
No full textBackground: Nasopharyngeal carcinoma (NPC) is a highly malignant head and neck tumor, with most patients having lymph node metastasis at the time of diagnosis. Studies have shown that forkhead box protein O-1 (FOXO-1) and nuclear factor kappa-B (NF-κB) are associated with resistance to radiotherapy and chemotherapy in NPC. Baicalein can play an anti-inflammatory role by negatively regulating the activation of NF-κB and FOXO. The aim of this study was to investigate the effect of baicalein on the FOXO-1/NF-κB pathway in NPC. Methods: The human NPC cell line CNE-2 was treated with baicalein at low (20 μmol/L), medium (40 μmol/L) and high (80 μmol/L) concentrations. The effects of baicalein on cell proliferation, apoptosis and invasion were detected by methyl thiazolyl tetrazolium (MTT) assay, flow cytometry and transwell assay. The expressions of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-6, B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax), Cleaved-caspase 3, FOXO-1, p-FOXO-1 and NF-κB in each group were evaluated by Western blot (WB) analysis. The animal model of NPC was established and treated with baicalein (50 mg/kg), the weight and volume of tumor were measured. Histopathological changes were detected by hematoxylin-eosin (HE) staining. The expressions of FOXO-1, p-FOXO-1 and NF-κB were detected by WB. Results: Compared with the control group, the proliferation and invasive ability of CNE-2 decreased while the rate of cell apoptosis increased with the increase in the concentration of baicalein (p < 0.05). Compared with the control group, as the concentration of baicalein increased, the expression of TNF-α, IL-1β, IL-6, Bcl-2, p-FOXO-1 and NF-κB decreased while the expression of Bax and Cleaved-caspase 3 increased (p < 0.05). There was no significant change in the expression of FOXO-1 in each group. In the animal model of NPC, tumor in the control group grew rapidly and the tumor cells were closely arranged, whereas in the baicalein treated group, the tumor grew slowly and the cells were loosely arranged. There was no significant difference in the expression of FOXO-1 between the control and baicalein group (p > 0.05). However, the expressions of p-FOXO-1 and NF-κB were lower in the baicalein group compared to the control group (p < 0.05). Conclusion: Baicalein exerts anti-tumor effects in NPC by blocking the activation of the FOXO-1/NF-κB pathway, inhibiting the proliferation and invasion of tumor cells, up-regulating the level of cell apoptosis, and down-regulating the expression of inflammatory factors
Emodin Reduces Neuroinflammation in Rats with Acute Severe Craniocerebral Injury
No full textBackground: Acute severe craniocerebral injury (ASBI) is a leading cause of morbidity and mortality following trauma. Emodin has demonstrated a range of pharmacological effects, including anti-inflammatory and antioxidant properties. This study sought to investigate the effect of emodin on ASBI in rats and to elucidate its potential mechanisms. Methods: Thirty sprague-dawley (SD) rats were randomly assigned into five subgroups: the sham subgroup, the model subgroup, the low-dose emodin subgroup, the middle-dose subgroup, and the high-dose subgroup. Initially, we recorded the grip traction time and neurobehavioral scoring in each subgroup. Moreover, pathological injury in brain tissue was observed using hematoxylin-eosin (H&E) staining. Immunohistochemical staining was utilized to evaluate the levels of positive glial fibrillary acidic protein (GFAP) and ionized calcium-binding adapter molecule 1 (Iba1). Furthermore, the levels of cytokines were assessed using biochemical assays. The levels of reactive oxygen species (ROS) in the brain tissue were determined using a 2′,7′-dichlorodihydrofluorescein diacetate (DCFH-DA) probe. Additionally, the mRNA levels of inducible nitric oxide synthase (iNOS) and p38 mitogen-activated protein kinase (p38 MAPK) were evaluated employing quantitative real-time polymerase chain reaction (qRT-PCR). Heat shock proteins 70 (HSP70), B cell lymphoma-2 (Bcl-2), Bcl-2 associated X-protein (Bax), NOD-like receptor (NLR) family pyrin domain-containing protein 3 (NLRP3), caspase-1, iNOS, phosphorylated-p38 MAPK (p-p38 MAPK), p38 MAPK levels in the brain tissue were examined utilizing Western blot analysis. Results: Emodin treatment significantly improved the neurobehavioral and pathological damage of brain tissue in ASBI rats. HSP70, Bcl-2, glutathione (GSH), and superoxide dismutase (SOD) levels were substantially elevated in the brain tissue of the emodin subgroup. Conversely, emodin treatment reduced the levels of Bax, NLRP3, caspase-1, malondialdehyde (MDA), nitric oxide (NO), and ROS. Furthermore, serum levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, interferon-γ (IFN-γ), and IL-6 were significantly reduced in the emodin subgroup compared to the model subgroup (p < 0.05). Additionally, iNOS mRNA and protein levels were reduced in the brain tissue of the emodin subgroup compared to the model subgroup (p < 0.05). Similarly, the p-p38 MAPK protein concentrations were also alleviated in the brain tissue of the emodin subgroup compared to the model subgroup (p < 0.05). Conclusion: Emodin enhances motor function recovery, mitigates apoptosis and neuroinflammation, and reduces oxidative stress in ASBI rats, potentially through the p38 MAPK signaling pathway
Unveiling the Medicinal Power of Citrus limon Essential Oil: A Comprehensive Exploration of Antioxidant and Antimitotic Properties, Phytochemical Composition, and Molecular Inter-Actions
No full textBackground: The essential oil (EO) extracted from Citrus limon has gained attention for its potential bioactive properties due to its promising chemical composition. This study aimed to comprehensively evaluate the antioxidant and antimitotic activities of Citrus limon EO. Methods: Volatile compounds were thoroughly analyzed using headspace and gas chromatography techniques. Molecular docking studies identified D-limonene and α-bergamotene as having the highest antioxidant potential. Assessment of antioxidant capacity employed 2,2-diphenyl-1-picrylhydrazyl (DPPH) and β-Carotene bleaching assays, alongside the Total Antioxidant Capacity (TAC) assay. Absorption, distribution, metabolism, excretion and toxicity (ADMET) tests were conducted to confirm the EOs suitability for pharmaceutical applications. The antimitotic activity was evaluated using the Lepidium sativum test. Results: Results indicated a 1.99% essential oil yield, with D-limonene identified as the predominant constituent. In the DPPH assay, the half-maximal inhibitory concentration (IC50) value was 1.27 ± 0.03 mg/mL, and the β-carotene bleaching assay exhibited an IC50 value of 6.74 ± 0.12 mg/mL. The TAC assay determined the EOs total antioxidant capacity as 212.2 ± 1.35 μg Ascorbic acid (AA) eq/mg EO. The essential oil demonstrated significant antimitotic activity, reaching a maximum of 83.33% at a concentration of 250 μg/mL. Conclusions: These findings underscore the noteworthy antioxidant and antimitotic capabilities of Citrus limon essential oil, primarily attributed to D-limonene and other bioactive components
CDP-Diacylglycerol Synthase 1 Promotes Proliferation, Invasion, and Metastasis in Hepatocellular Carcinoma
No full textBackground: CDP-diacylglycerol synthase 1 (CDS1), a functional protein regulating cell growth and lipid synthesis, is implicated in cancer development. Despite its potential role, the impact of CDS1 in hepatocellular carcinoma (HCC) remains elusive. This study aimed to explore the role of CDS1 on HCC progression. Finally, we elucidated whether CDS1 affects HCC pathogenesis and its associated signal transduction. Methods: CDS1 expression was assessed in tissue samples, correlating with clinical characteristics and prognostic outcomes in HCC. Vector, CDS1 overexpression, si-CDS1-2, and si-CDS1-3 groups were established using primary liver cancer tissues, adjacent normal tissues, human HCC cells, liver epithelial cells, and RNA/proteins extracts. In vitro and in vivo experiments were performed to determine the biological function and molecular basis of CDS1, including Cell Counting Kit-8, cell cycle, and 5-ethynyl-2′-deoxyuridine assays for proliferation, Transwell and Boyden assays for invasion and metastasis. Moreover, apoptosis assay, quantitative real-time polymerase chain reaction, and western blotting were shown. Results: Analysis of The Cancer Genome Atlas datasets revealed a significant increase in CDS1 expression in HCC, suggesting a potential influence on liver cancer cell growth, invasion, and apoptosis. Immunohistochemical analysis revealed elevated CDS1 protein levels in HCC samples compared to adjacent tissues. Furthermore, western blotting revealed a plausible carcinogenic role of CDS1 in HCC linked to the RAC-Alpha Serine/Threonine-Protein Kinase (AKT)-Mechanistic Target of Rapamycin (mTOR) signaling pathway. Finally, experimental findings confirmed that CDS1 promotes HCC proliferation, invasion, and metastasis while inhibiting apoptosis, potentially through the AKT-TSC2-mTOR pathway. Conclusions: CDS1 modulates the proliferation, migration, and invasion of liver cancer cells, impeding normal apoptotic processes. The underlying mechanism includes the activation of the AKT-TSC2-mTOR signaling pathway