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1.
RSC Adv ; 14(40): 29648-29657, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39297034

RESUMO

The increasing need to tackle major societal challenges such as environmental sustainability and resource scarcity has heightened global interest in green and efficient separation technologies. The separation of organic acids, particularly tartaric acid, holds significant industrial importance in the food and pharmaceutical sectors. Purifying tartaric acid is crucial due to its roles as a chiral catalyst, antioxidant, and stabilizer, which are vital for ensuring product quality and efficiency. In this study, we synthesized heterogeneous anion exchange membranes by casting a solution of polyacrylonitrile (PAN) homogeneously dispersed with micronized anion exchange resin [polystyrene-divinylbenzene-trimethyl ammonium chloride (PS-DVB-TAC)]. These membranes were further coated with polyaniline (PANI) through in situ polymerization at different time intervals such as 2, 12, and 24 h. Cation exchange membranes were also prepared by solution casting of PAN dispersed with micronized cation exchange resin, sulfonated poly-styrene-co-divinylbenzene, and SPS-DVB. These synthesized anion exchange membranes with and without a PANI coating were examined for their separation performance of tartaric acid, along with the cation exchange membranes in a four-compartment electrodialyser at a constant voltage. The newly fabricated membranes were characterized by different techniques, including attenuated total reflectance-Fourier transform infrared spectroscopy for functional group analysis, scanning electron microscopy for their surface morphology, and the four-probe method for electrical conductivity. In addition, ion exchange capacity and water uptake have been measured. The electrodialysis experiments showed that 14.82 wt% of tartrate ions moved into the product compartment through the uncoated anion exchange membrane within 30 min at a voltage of 30 V. Under the same conditions, membranes coated with PANI at 2, 12, and 24 h raised the separation efficiency to 21.19%, 34.13%, and 37.21%, respectively. Findings indicate that membranes coated with PANI for extended periods demonstrate superior separation efficiency for tartaric acid. Consequently, this energy-efficient method shows significant potential for application in the food and pharmaceutical industries for separating tartaric acid and other organic and amino acids. This research can advance practical and sustainable separation technologies, addressing critical societal issues like resource efficiency and environmental sustainability.

2.
Sci Total Environ ; 954: 175876, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39244053

RESUMO

Bisphenol A (BPA) is an endocrine-disrupting toxicant commonly used in the plastics industry, as a result, it is present in large quantities in the environment. Therefore, current study was designed to assess BPA induced neurotoxicity and molecular fate within common carp (Cyprinus carpio), largely used edible fish. Following 6 weeks exposure to BPA 1/5th of 96 h LC50 (1.31 mg/L), brain exhibited oxidative damage, which was evidenced by compromised antioxidant system (CAT, SOD, GSH) and increased level of biomacromolecule peroxidation (MDA and 8-OHDG). Functional damage to the brain observed in the form of blood-brain barrier disruption (decreased tight junction gene expression) and nerve conduction impairment (reduced acetylcholinesterase activity). Mechanistically, apoptotic cell death indicated by characteristic alteration in key biomarkers (bcl-2, caspase, and p53-related gene family). Whereas, coadministration of powdered PP (pomegranate peel) (8 %) with BPA effectively mitigated the BPA toxicity, as evidenced by the restoration of the above-mentioned bioindicators. Thereby, BPA-induced neurotoxicity could be potentially detoxified by applying PP dietary enrichment.

3.
Pak J Med Sci ; 40(8): 1601-1607, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39281222

RESUMO

Objectives: To compare the outcomes of modified extended right lobe graft (MERLG) and modified right lobe graft (MRLG) in living-donor liver transplantation (LDLT). Methods: This retrospective study was performed at the Liver transplant department of the Pir Abdul Qadir Shah Jeelani Institute of Medical Sciences Hospital, Gambat, Pakistan, from March 2019 to September 2020. The outcomes of 20 MERLG donors and recipients were compared to those of 74 MRLG donors and recipients. Demographics, operative parameters, complications, hospital stay, and one-year survival were compared between the two groups. Results: The mean graft volume of the MERLG group was more (637.10 ± 71.35 g) than in the MRLG group (562.27 ± 57.77 g), (p= 0.001). Donor blood loss was higher in the MERLG group (680.10±170.60 ml) compared to the MRLG group (650.23±190.65 ml), p=0.527. In addition, the operative time was longer in the MERLG group (345.80±76.90 min) than in the MRLG group (318.12±100.80 min) (p= 0.257). The MERLG recipients were sicker (mean MELD score of 22.54±3.67) than the MRLG (18.86±4.37) (p=0.001). The drain output was higher in the MRLG group (1340 ± 470.32 ml) than in the MERLG group (1110 ± 450.60 ml) (P =0.045). No significant difference was found when comparing postoperative laboratory results and complications between the donor and recipient groups (p >0.05). Kaplan-Meier analysis showed a 95% one-year survival in MERLG group compared to 90.7% in the MRLG group (p=0.549). Conclusion: With appropriate technical expertise, MERLGs are technically safe and feasible in LDLT donors without any added risks. MERLGs also yielded better outcomes in sick recipients.

4.
Sci Rep ; 14(1): 18604, 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-39127761

RESUMO

Silica fiber under high pressure increases the risk of fiber breakage or permanent deformation, which may cause sensor failure due to mechanical strength limitations. High pressure can also induce birefringence in optical fiber. In this study, we present a simple design and low-cost high pressure sensor using polymer optical fiber (POF) based on the intensity-variation technique. A side-coupling mechanism in the sensor structure is adopted, which varies the intensity with applied pressure. Two POFs are twisted together to create a sensing region where the light is launched in the first fiber and measurement is taken from the second fiber. In sensing phenomena, cladding mode frustrated total internal reflection occurs when pressure increases. Silicone gel is used in the pressure chamber for sealing and preventing leakage. The sensor structure is able to detect high pressure in the MPa range, where we tested up to 4 MPa. For higher sensitivity, twisted and bend structure is analyzed, and sensitivity is achieved at about 432.21 nW/MPa. However, twisted helical structure is adopted to enhance sensing range which is about 50 cm. The proposed high-pressure sensor structure is easier to fabricate and has high stability because it doesn't require any destructive method as compared to other conventional methods.

6.
Adv Colloid Interface Sci ; 331: 103241, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38909547

RESUMO

Solid Oxide Fuel Cells (SOFCs) have proven to be highly efficient and one of the cleanest electrochemical energy conversion devices. However, the commercialization of this technology is hampered by issues related to electrode performance degradation. This article provides a comprehensive review of the various degradation mechanisms that affect the performance and long-term stability of the SOFC anode caused by the interplay of physical, chemical, and electrochemical processes. In SOFCs, the most used anode material is nickel-yttria stabilized zirconia (Ni-YSZ) due to its advantages of high electronic conductivity and high catalytic activity for H2 fuel. However, various factors affecting the long-term stability of the Ni-YSZ anode, such as redox cycling, carbon coking, sulfur poisoning, and the reduction of the triple phase boundary length due to Ni particle coarsening, are thoroughly investigated. In response, the article summarizes the state-of-the-art diagnostic tools and mitigation strategies aimed at improving the long-term stability of the Ni-YSZ anode.

7.
Cancers (Basel) ; 16(11)2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38893154

RESUMO

Hepatocellular carcinoma (HCC) is the deadliest emergent health issue around the globe. The stronger oncogenic effect, proteins, and weakened immune response are precisely linked with a significant prospect of developing HCC. Several conventional systemic therapies, antiangiogenic therapy, and immunotherapy techniques have significantly improved the outcomes for early-, intermediate-, and advanced-stage HCC patients, giving new hope for effective HCC management and prolonged survival rates. Innovative therapeutic approaches beyond conventional treatments have altered the landscape of managing HCC, particularly focusing on targeted therapies and immunotherapies. The advancement in HCC treatment suggested by the Food and Drug Administration is multidimensional treatment options, including multikinase inhibitors (sorafenib, lenvatinib, regorafenib, ramucirumab, and cabozantinib) and immune checkpoint inhibitors (atezolizumab, pembrolizumab, durvalumab, tremelimumab, ipilimumab, and nivolumab), in monotherapy and in combination therapy to increase life expectancy of HCC patients. This review highlights the efficacy of multikinase inhibitors and immune checkpoint inhibitors in monotherapy and combination therapy through the analysis of phase II, and III clinical trials, targeting the key molecular pathways involved in cellular signaling and immune response for the prospective treatment of advanced and unresectable HCC and discusses the upcoming combinations of immune checkpoint inhibitors-tyrosine kinase inhibitors and immune checkpoint inhibitors-vascular endothelial growth factor inhibitors. Finally, the hidden challenges with pharmacological therapy for HCC, feasible solutions for the future, and implications of possible presumptions to develop drugs for HCC treatment are reported.

8.
Ambio ; 53(11): 1686-1713, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38822966

RESUMO

Climate change and CO2 emissions are critical challenges for the environment and humanity. There is extensive literature on greenhouse gas (GHG) emissions, in particular CO2 emissions. However, comprehensive analyses focusing on electric vehicles (EVs) and their impact are lacking. This study fills this gap by conducting a bibliometric analysis of 1143 peer-reviewed studies from 1989 to 2023. We aimed to identify influential contributions, understand the field's structure, and reveal research gaps. Analysis included citation networks, research impact, authorship patterns, content, and publication trends. We utilized bibliometric techniques to identify the most dominant countries, institutions, authors, journals, articles, and thematic areas related to EVs and emissions. Additionally, we overviewed publications associated with key search terms. Guided by five research dimensions (EVs, emissions, adoption, policies, and infrastructures), we framed specific research questions. This research provides valuable insights for environmentalists, policymakers, regulators, and academic researchers, facilitating access to crucial data on EVs and emissions.


Assuntos
Mudança Climática , Emissões de Veículos , Emissões de Veículos/análise , Bibliometria , Gases de Efeito Estufa/análise , Dióxido de Carbono/análise , Veículos Automotores
9.
Sci Rep ; 14(1): 10927, 2024 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-38740856

RESUMO

To study the dynamical system, it is necessary to formulate the mathematical model to understand the dynamics of various diseases which are spread in the world wide. The objective of the research study is to assess the early diagnosis and treatment of cholera virus by implementing remedial methods with and without the use of drugs. A mathematical model is built with the hypothesis of strengthening the immune system, and a ABC operator is employed to turn the model into a fractional-order model. A newly developed system SEIBR, which is examined both qualitatively and quantitatively to determine its stable position as well as the verification of flip bifurcation has been made for developed system. The local stability of this model has been explored concerning limited observations, a fundamental aspect of epidemic models. We have derived the reproductive number using next generation method, denoted as " R 0 ", to analyze its impact rate across various sub-compartments, which serves as a critical determinant of its community-wide transmission rate. The sensitivity analysis has been verified according to its each parameters to identify that how much rate of change of parameters are sensitive. Atangana-Toufik scheme is employed to find the solution for the developed system using different fractional values which is advanced tool for reliable bounded solution. Also the error analysis has been made for developed scheme. Simulations have been made to see the real behavior and effects of cholera disease with early detection and treatment by implementing remedial methods without the use of drugs in the community. Also identify the real situation the spread of cholera disease after implementing remedial methods with and without the use of drugs. Such type of investigation will be useful to investigate the spread of virus as well as helpful in developing control strategies from our justified outcomes.


Assuntos
Cólera , Modelos Teóricos , Cólera/epidemiologia , Humanos , Epidemias/prevenção & controle , Simulação por Computador
10.
Biochem Genet ; 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38816671

RESUMO

MicroRNAs (miRNAs) are short, endogenously encoded small RNAs, 18-26 nucleotides in length, which can posttranscriptionally regulate gene expression through translation inhibition or endonucleolytic cleavage. The muskmelon is one of the most widely cultivated fruits in the Cucurbitaceae family. Despite its significance, only 120 miRNAs from different families have been reported in muskmelon. In this study, we aimed to expand this knowledge base by predicting 40 new miRNAs in muskmelon using a spectrum of genomic-based tools. Precursor and mature sequences were obtained from microRNA registry database as reference and analyzed via the basic local alignment search tool (Blastn) for ESTs identification. After removing the non-coding sequences, the remaining candidate sequences were analyzed using MFOLD to generate secondary structures for the newly predicted miRNAs. Additionally, the predicted muskmelon miRNAs were validated using a set of five randomly chosen primers and RT-PCR. Through gene ontology (GO) analysis, we identified 89 targets associated with newly predicted muskmelon miRNAs. Transcription factor-coding genes play a crucial role in plant growth and development. Additionally, the miR4249 has been found to have the same targets in muskmelon that have been linked to cell signaling and transcription factors. The identified targets are integral for diverse biological processes including plant growth, development, metabolism, aging, disease resistance, and resistance to environmental stresses, such as salt, cold, and oxidative stress. As a result, the outcomes of this study demonstrate that this mechanism not only contributes to the production of a higher quality crop but also enhances overall production.

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