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Metabolism controls cellular phenotype and fate. In this report, we demonstrate that nicotinamide N-methyltransferase (NNMT), a metabolic enzyme that regulates developmental stem cell transitions and tumor progression, is highly expressed in human idiopathic pulmonary fibrosis (IPF) lungs, and is induced by the pro-fibrotic cytokine, transforming growth factor-ß1 (TGF-ß1) in lung fibroblasts. NNMT silencing reduces the expression of extracellular matrix proteins, both constitutively and in response to TGF-ß1. Furthermore, NNMT controls the phenotypic transition from homeostatic, pro-regenerative lipofibroblasts to pro-fibrotic myofibroblasts. This effect of NNMT is mediated, in part, by the downregulation of lipogenic transcription factors, TCF21 and PPARγ, and the induction of a less proliferative but more differentiated myofibroblast phenotype. NNMT confers an apoptosis-resistant phenotype to myofibroblasts that is associated with the downregulation of pro-apoptotic members of the Bcl-2 family, including Bim and PUMA. Together, these studies indicate a critical role for NNMT in the metabolic reprogramming of fibroblasts to a pro-fibrotic and apoptosis-resistant phenotype and support the concept that targeting this enzyme may promote regenerative responses in chronic fibrotic disorders such as IPF.
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Miofibroblastos , Nicotinamida N-Metiltransferase , Humanos , Apoptose , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Fibroblastos/metabolismo , Fibrose , Fibrose Pulmonar Idiopática/metabolismo , Pulmão/metabolismo , Miofibroblastos/metabolismo , Nicotinamida N-Metiltransferase/metabolismo , Fator de Crescimento Transformador beta1/metabolismoRESUMO
Fibrosis involving the lung may occur in many settings, including in association with known environmental agents, connective tissue diseases, and exposure to drugs or radiation therapy. The most common form is referred to as 'idiopathic' since a causal agent or specific association has not been determined; the strongest risk factor for idiopathic pulmonary fibrosis is aging. Emerging studies indicate that targeting certain components of aging biology may be effective in mitigating age-associated fibrosis. While transforming growth factor-ß1 (TGF-ß1) is a central mediator of fibrosis in almost all contexts, and across multiple organs, it is not feasible to target this canonical pathway at the ligand-receptor level due to the pleiotropic nature of its actions; importantly, its homeostatic roles as a tumor-suppressor and immune-modulator make this an imprudent strategy. However, defining targets downstream of its receptor(s) that mediate fibrogenesis, while relatively dispenable for tumor- and immune-suppressive functions may aid in developing safer and more effective therapies. In this review, we explore molecular targets that, although TGF-ß1 induced/activated, may be relatively more selective in mediating tissue fibrosis. Additionally, we explore epigenetic mechanisms with global effects on the fibrogenic process, as well as metabolic pathways that regulate aging and fibrosis.
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Fibrose Pulmonar Idiopática , Fator de Crescimento Transformador beta1 , Fibroblastos/metabolismo , Fibrose , Humanos , Fibrose Pulmonar Idiopática/metabolismo , Pulmão/metabolismo , Fator de Crescimento Transformador beta1/metabolismoRESUMO
MicroRNAs (miRs) and Hox transcription factors have decisive roles in postnatal bone formation and homeostasis. In silico analysis identified extensive interaction between HOXA cluster mRNA and microRNAs from the miR-23a cluster. However, Hox regulation by the miR-23a cluster during osteoblast differentiation remains undefined. We examined this regulation in preosteoblasts and in a novel miR-23a cluster knockdown mouse model. Overexpression and knockdown of the miR-23a cluster in preosteoblasts decreased and increased, respectively, the expression of the proteins HOXA5, HOXA10, and HOXA11; these proteins' mRNAs exhibited significant binding with the miR-23a cluster miRNAs, and miRNA 3'-UTR reporter assays confirmed repression. Importantly, during periods correlating with development and differentiation of bone cells, we found an inverse pattern of expression between HoxA factors and members of the miR-23a cluster. HOXA5 and HOXA11 bound to bone-specific promoters, physically interacted with transcription factor RUNX2, and regulated bone-specific genes. Depletion of HOXA5 or HOXA11 in preosteoblasts also decreased cellular differentiation. Additionally, stable overexpression of the miR-23a cluster in osteoblasts decreased the recruitment of HOXA5 and HOXA11 to osteoblast gene promoters, significantly inhibiting histone H3 acetylation. Heterozygous miR-23a cluster knockdown female mice (miR-23a ClWT/ZIP) had significantly increased trabecular bone mass when compared with WT mice. Furthermore, miR-23a cluster knockdown in calvarial osteoblasts of these mice increased the recruitment of HOXA5 and HOXA11, with a substantial enrichment of promoter histone H3 acetylation. Taken together, these findings demonstrate that the miR-23a cluster is required for maintaining stage-specific HoxA factor expression during osteogenesis.
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Regiões 3' não Traduzidas , Diferenciação Celular , Proteínas de Homeodomínio/metabolismo , MicroRNAs/metabolismo , Família Multigênica , Osteoblastos/metabolismo , Fosfoproteínas/metabolismo , Acetilação , Animais , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Células HEK293 , Histonas/genética , Histonas/metabolismo , Proteínas de Homeodomínio/genética , Humanos , Camundongos , MicroRNAs/genética , Osteoblastos/citologia , Osteogênese , Fosfoproteínas/genética , Fatores de TranscriçãoRESUMO
India has emerged as a key player with a high potential to develop a biomass and biobased economy due to its large geographic size and the massive amounts of agricultural and non agricultural biomass produced. India has joined hands with Europe to synchronize its efforts to create and facilitate the development of a biobased economy in this country. This paper aims to examine common research and development actions between the European Union (EU) and India to facilitate the development of these biobased economies. As a base, a thorough study has been performed considering the biomass potential and current status of the bioeconomy in both the EU and India based on the distillation of a series of 80 potential recommendations. The recommendations were grouped into four major categories: (1) biomass production, (2) by-products/waste, (3) biorefineries and (4) policy, market, and value-added products. A questionnaire was designed and distributed to key stakeholders belonging to: academia, industry, and policymakers in both India and the EU. A total of 231 responses were received and analyzed, based on the key recommendations made for the essential research and development topics that are of prime importance to develop biobased economies in both the EU and India. The findings of this study suggest recognizing the value-added contributions made by biobased products such as: food, feed, valuable materials and chemicals in both regions. It is important to reduce the overall process costs and minimize the environmental impacts of such a biobased economy.
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Biotecnologia , Biomassa , Biotecnologia/economia , Biotecnologia/organização & administração , Biotecnologia/tendências , Europa (Continente) , Humanos , ÍndiaRESUMO
This paper aims to examine the influence of various catalysts on biodiesel production, especially from non-food feedstocks with an ambition to optimize the catalytic biodiesel production. Homogenous acid catalysts are mainly used in biodiesel production, but they cannot be recovered and demand costly fuel purification as being corrosive. Similarly, enzyme catalysts are expensive in industrial-scale production of biodiesel. However, heterogeneous catalysts simplify the easy separation of product and by-products from the catalyst along with catalyst reusability and reduction of waste. Solid acid and base catalysts offer more advantages due to their non-toxicity, high surface area, reusability, higher stability, and the simplicity of purification. Solid base catalysts yield better activity than solid acid catalysts, however, they cannot esterify large amounts of free fatty acids (FFAs) in non-food feedstocks. The solid acid catalysts have the added advantages of being more tolerant to high amounts of FFAs and being able to simultaneously esterify FFAs and transesterify triglycerides in cheap feedstocks like waste cooking oil. Recently, an array of inorganic, organic and polymeric solid acid and nanomaterial-based catalysts have been developed using cheap feedstocks. However, the issues of low reactivity, small pore sizes, low stabilities, long reaction times, and high reaction temperatures still need to be solved. The developments of producing efficient, cheap, durable, and stable solid acid and nanomaterial-based catalysts have been critically reviewed in this study. Furthermore, the challenges and future perspectives of production of biodiesel and its industry growth have also been discussed.
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Biocombustíveis , Óleos de Plantas , Catálise , Esterificação , Ácidos Graxos não EsterificadosRESUMO
Disclosed herein is an efficient synthetic route for the synthesis of functionalized 2-benzyl benzo[b]furans via a regioselective 5-exo-trig intramolecular oxidative cyclization of ortho-cinnamyl phenols using [PdCl2(CH3CN)2] as catalyst and benzoquinone as an oxidant. Further, a sequential ortho-cinnamylation of phenols using cinnamyl alcohols catalyzed by Re2O7, followed by an oxidative cyclization using the above Pd catalyst, is performed. The reaction showed broad substrate scope with good to excellent yields.
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An unprecedented approach for the synthesis of homo- and hetero-1,2,4-triaryl benzenes has been developed using a simple base-mediated reaction of either α-aryl cinnamyl alcohols or α,γ-di-aryl propanones. The salient feature of this strategy involves the sequential hydride transfer, regiospecific condensation, regiospecific dearylation, and aromatization under metal-free reaction conditions. The synthesis of unsymmetrically substituted triphenylenes by oxidative coupling of the synthesized 1,2,4-triaryl benzenes has also been demonstrated.
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An unprecedented dehydrative C-C bond formation between unprotected anilines with benzyl alcohols is disclosed. Re2O7 catalyst (5 mol %) at elevated reaction temperature (80 °C) provided C-benzylanilines with high to excellent yields and with good chemoselectivities (over N-alkylation). A probable mechanism has been proposed based on mechanistic studies.
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Compostos de Anilina/química , Álcoois Benzílicos/química , Rênio/química , Alquilação , Catálise , Estrutura Molecular , EstereoisomerismoRESUMO
PURPOSE: The aim of this work was to investigate the influence of hydroxypropyl methylcellulose (HPMC) on the phase transformation and release profile of carbamazepine-nicotinamide (CBZ-NIC) cocrystal in solution and in sustained release matrix tablets. METHODS: The polymorphic transitions of the CBZ-NIC cocrystal and its crystalline properties were examined by differential scanning calorimetry (DSC), X-ray powder diffraction (XRPD), Raman spectroscopy, and scanning electron microscopy (SEM). RESULTS: The apparent CBZ solubility and dissolution rate of CBZ-NIC cocrystal were constant in different concentrations of HPMC solutions. In a lower percentage of HPMC in the matrix tablets, the CBZ release profile of the CBZ-NIC cocrystal was nonlinear and declined over time. With an increased HPMC content in the tablets, the CBZ-NIC cocrystal formulation showed a significantly higher CBZ release rate in comparison with the other two formulations of CBZ III and the physical mixture. CONCLUSIONS: Because of a significantly improved dissolution rate of the CBZ-NIC cocrystal, the rate of CBZ entering into solution is significantly faster than the rate of formation of the CBZ-HPMC soluble complex in solution, leading to a higher supersaturation level of CBZ and subsequently precipitation of CBZ dihydrate.
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Analgésicos não Narcóticos/administração & dosagem , Carbamazepina/administração & dosagem , Preparações de Ação Retardada/química , Derivados da Hipromelose/química , Niacinamida/administração & dosagem , Complexo Vitamínico B/administração & dosagem , Analgésicos não Narcóticos/química , Carbamazepina/química , Cristalização , Niacinamida/química , Transição de Fase , Difração de Pó , Solubilidade , Comprimidos , Complexo Vitamínico B/química , Difração de Raios XRESUMO
Aim: This study investigates the altered expression and CpG methylation patterns of histone demethylase KDM8 in hepatocellular carcinoma (HCC), aiming to uncover insights and promising diagnostics biomarkers. Materials & methods: Leveraging TCGA-LIHC multi-omics data, we employed R/Bioconductor libraries and Cytoscape to analyze and construct a gene correlation network, and LASSO regression to develop an HCC-predictive model. Results: In HCC, KDM8 downregulation is correlated with CpGs hypermethylation. Differential gene correlation analysis unveiled a liver carcinoma-associated network marked by increased cell division and compromised liver-specific functions. The LASSO regression identified a highly accurate HCC prediction signature, prominently featuring CpG methylation at cg02871891. Conclusion: Our study uncovers CpG hypermethylation at cg02871891, possibly influencing KDM8 downregulation in HCC, suggesting these as promising biomarkers and targets.
Changes in gene function can play a role in causing cancer. In this study, we looked at how a specific gene called KDM8 behaves in liver cancer. By analyzing a large set of liver cancer samples, we investigated how gene interactions are different in this disease and if they can help predict liver cancer risk. Our results show that the KDM8 gene is less active, and its DNA gets chemically modified more often in liver cancer. We also found a group of genes and DNA changes, which are linked to the disease. Using this information, we identified 16 important markers and built a computer model that can accurately predict liver cancer. We found that DNA methylation at a specific spot called cg02871891 is especially important for predicting liver cancer. Overall, our study suggests that high levels of DNA methylation may lead to reduced KDM8 activity in liver cancer, which could be important for future research and better diagnostic tools.
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The observation of thioester-mediated acyl transfer processes in nature has inspired the development of novel protein synthesis and functionalization methodologies. The chemoselective transfer of an acyl group from S-to-N is the basis of several powerful ligation strategies. In this work, we sought to apply the reverse process, the transfer of an acyl group from N-to-S, as a method to convert stable chiral amides into more reactive thioesters. To this end, we developed a novel cysteine-derived oxazolidinone that serves as both a chiral imide auxiliary and an acyl transfer agent. This auxiliary combines the desirable features of rigid chiral imides as templates for asymmetric transformations with the synthetic applicability of thioesters. We demonstrate that the auxiliary can be applied in a range of highly selective asymmetric transformations. Subsequent intramolecular N-to-S acyl transfer of the chiral product and in situ trapping of the resulting thioester provides access to diverse carboxylic acid derivatives under mild conditions. The oxazolidinone thioester products can also be isolated and used in Pd-mediated transformations to furnish highly valuable chiral scaffolds, such as noncanonical amino acids, cyclic ketones, tetrahydropyrones, and dihydroquinolinones. Finally, we demonstrate that the oxazolidinone thioesters can also serve as a surrogate for SNAC-thioesters, enabling their seamless use as non-native substrates in biocatalytic transformations.
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The unique properties of NB, such as its nano-size effect and greater adsorption capacity, have the potential to mitigate ammonia (NH3) emission, but may also pose threats to soil life and their associated processes, which are not well understood. We studied the influence of different NB concentrations on NH3 emission, soil microbial biomass, nutrient mineralization, and corn nutrient uptake from farmyard manure (FM). Three different NB concentrations i.e., 12.5 (NB1), 25 (NB2), and 50% (NB3), alone and in a fertilizer mixture with FM, were applied to corn. NB1 alone increased microbial biomass in soil more than control, but other high NB concentrations did not influence these parameters. In fertilizer mixtures, NB2 and NB3 decreased NH3 emission by 25% and 38%, respectively, compared with FM alone. Additionally, NB3 significantly decreased microbial biomass carbon, N, and soil potassium by 34%, 36%, and 14%, respectively, compared with FM. This toxicity to soil parameters resulted in a 21% decrease in corn K uptake from FM. Hence, a high NB concentration causes toxicity to soil microbes, nutrient mineralization, and crop nutrient uptake from the FM. Therefore, this concentration-dependent toxicity of NB to soil microbes and their associated processes should be considered before endorsing NB use in agroecosystems.
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Multi-target directed ligands (MTDLs) have recently attracted significant interest due to their exceptional effectiveness against multi-factorial Alzheimer's disease. The present work described the development of pyrazine-based MTDLs using multicomponent Petasis reaction for the dual inhibition of tau-aggregation and human acetylcholinesterase (hAChE). The molecular structure of synthesized ligands was validated by 1H & 13C NMR and mass spectrometry. The screened compounds were shown to have a strong inhibitory effect at 10 µM concentration against tau-oligomerization and hAChE, but only moderate inhibitory activity against Aß42. Among all the compounds, the half-maximal inhibitory concentration (IC50) for 21 and 24 against hAChE were 0.71 µM and 1.09 µM, respectively, while they displayed half-maximal effective concentrations (EC50) values of 2.21 µM and 2.71 µM for cellular tau-oligomerization, respectively. Additionally, an MTT experiment using tau-expressing SH-SY5Y neuroblastoma cells revealed that 21 was more neuroprotective than the FDA-approved medication donepezil. Furthermore, an MD simulation study was performed to investigate the dynamics and stability of AChE-21 and AChE-24 complexes in an aqueous environment. The MM-PBSA calculations were performed to evaluate the binding of 21 and 24 with AChE, and the relative binding energy was calculated as -870.578 and -875.697 kJ mol-1, respectively. As a result, the study offered insight into the design of new MTDLs and highlighted 21 as a potential roadblock to the development of anti-AD medications.
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Doença de Alzheimer , Neuroblastoma , Fármacos Neuroprotetores , Humanos , Inibidores da Colinesterase/química , Relação Estrutura-Atividade , Acetilcolinesterase/metabolismo , Desenho de Fármacos , Neuroblastoma/tratamento farmacológico , Doença de Alzheimer/tratamento farmacológico , Simulação de Acoplamento Molecular , Fármacos Neuroprotetores/química , Peptídeos beta-Amiloides/metabolismoRESUMO
The massive production and extensive use of fossil-based non-biodegradable plastics are leading to their environmental accumulation and ultimately cause health threats to animals, humans, and the biosphere in general. The problem can be overcome by developing eco-friendly ways for producing plastics-like biopolymers from waste residues such as of agricultural origin. This will solve two currently prevailing social issues: waste management and the efficient production of a biopolymer that is environmentally benign, polyhydroxyalkanoates (PHA). The current study assesses the environmental impact of biopolymer (PHA) manufacturing, starting from slaughterhouse waste as raw material. The Material Input Per Service Unit methodology (MIPS) is used to examine the sustainability of the PHA production process. In addition, the impact of shifting from business-as-usual energy provision (i.e., electricity from distribution grid network and heat provision from natural gas) to alternative renewable energy sources is also evaluated. As a major outcome, it is shown that the abiotic material contribution for PHA production process is almost double for using hard coal as an energy source than the petro-plastic low-density-poly(ethene) (LPDE), which PHA shall ultimately replace. Likewise, abiotic material contribution is 43 % and 7 % higher when using the electricity from the European electricity mix (EU-27 mix) and biogas, respectively, than in the case of LDPE production. However, PHA production based on wind power for energy provision has 12 % lower abiotic material input than LDPE. Furthermore, the water input decreases when moving from the EU-27 mix to wind power. The reduction in water consumption for various electricity provision resources amounts to 20 % for the EU-27 mix, 25 % for hard coal, 71 % for wind, and 70 % for biogas. As the main conclusion, it is demonstrated that using wind farm electricity to generate PHA is the most environmentally friendly choice. Biogas is the second-best choice, although it requires additional abiotic material input.
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Poli-Hidroxialcanoatos , Humanos , Animais , Biocombustíveis , Polietileno , Biopolímeros , Carvão MineralRESUMO
Organophosphate flame retardants (OPEs) and phthalates have garnered significant attention due to their widespread presence in indoor environments. Many recent investigations have reported extensive contamination of indoor dust, air, children's toys, and other environmental compartments with these chemicals. This research aimed to analyze OPEs and phthalates in air (PM10) and dust samples collected from the bedrooms of children (N = 30) residing in various households in Jeddah, Saudi Arabia. High mean levels (ng/g) of phthalates namely DEHP (1438600) and DnBP (159200) were found in indoor dust while TPhP (5620) was the major OPEs in indoor dust. Similarly, DEHP and DnBP were the predominant phthalates in PM10 samples, exhibiting mean levels of 560 and 680 ng/m3, respectively. However, TCPP was the main OPEs with average levels of 72 ng/m3 in PM10 samples. The majority of individual phthalates and OPEs were detected in 90-100 % of the dust samples, whereas in PM10 samples, their presence ranged from 25 % to 100 %. The concentrations of OPEs were notably greater than those of PBDEs and other BFRs previously reported in these samples, suggesting their broader use than alternative BFRs. The estimated long-term non-carcinogenic risk, hazardous index (HI) and daily exposure via dust for children was above threshold levels for DEHP. On the other hand, the cumulative risk of cancer was below the concerning levels. Further research is required to explore diverse groups of chemicals in indoor microenvironments particularly significant for children, such as kindergartens, primary schools, and their rooms at home.
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Recently, solar photovoltaic (PV) technology has shown tremendous growth among all renewable energy sectors. The attractiveness of a PV system depends deeply of the module and it is primarily determined by its performance. The quantity of electricity and power generated by a PV cell is contingent upon a number of parameters that can be intrinsic to the PV system itself, external or environmental. Thus, to improve the PV panel performance and lifetime, it is crucial to recognize the main parameters that directly influence the module during its operational lifetime. Among these parameters there are numerous factors that positively impact a PV system including the temperature of the solar panel, humidity, wind speed, amount of light, altitude and barometric pressure. On the other hand, the module can be exposed to simultaneous environmental stresses such as dust accumulation, shading and pollution factors. All these factors can gradually decrease the performance of the PV panel. This review not only provides the factors impacting PV panel's performance but also discusses the degradation and failure parameters that can usually affect the PV technology. The major points include: 1) Total quantity of energy extracted from a photovoltaic module is impacted on a daily, quarterly, seasonal, and yearly scale by the amount of dust formed on the surface of the module. 2) Climatic conditions as high temperatures and relative humidity affect the operation of solar cells by more than 70% and lead to a considerable decrease in solar cells efficiency. 3) The PV module current can be affected by soft shading while the voltage does not vary. In the case of hard shadowing, the performance of the photovoltaic module is determined by whether some or all of the cells of the module are shaded. 4) Compared to more traditional forms of energy production, PV systems offer a significant number of advantages to the environment. Nevertheless, these systems can procure greenhouse gas emissions, especially during the production stages. In conclusion, this study underlines the importance of considering multiple parameters while evaluating the performance of photovoltaic modules. Environmental factors can have a major impact on the performance of a PV system. It is critical to consider these factors, as well as intrinsic and other intermediate factors, to optimize the performance of solar energy systems. In addition, continuous monitoring and maintenance of PV systems is essential to ensure maximum efficiency and performance.
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Gases de Efeito Estufa , Energia Solar , Poeira/análise , UmidadeRESUMO
Air pollution has serious environmental and human health-related consequences; however, little work seems to be undertaken to address the harms in Middle Eastern countries, including Saudi Arabia. We installed a continuous air quality monitoring station in Jeddah, Saudi Arabia and monitored several air pollutants and meteorological parameters over a 2-year period (2018-2019). Here, we developed two supervised machine learning models, known as quantile regression models, to analyze the whole distribution of the modeled pollutants, not only the mean values. Two pollutants, namely NO2 and O3, were modeled by dividing their concentrations into several quantiles (0.05, 0.25, 0.50, 0.75, and 0.95) and the effect of several pollutants and meteorological variables was analyzed on each quantile. The effect of the explanatory variables changed at different segments of the distribution of NO2 and O3 concentrations. For instance, for the modeling of O3, the coefficients of wind speed at quantiles 0.05, 0.25, 0.5, 0.75, and 0.95 were 1.40, 2.15, 2.34, 2.31, and 1.56, respectively. Correlation coefficients of 0.91 and 0.92 and RMSE values of 14.41 and 8.96, which are calculated for the cross-validated models of NO2 and O3, showed an acceptable model performance. Quantile analysis aids in better understanding the behavior of air pollution and how it interacts with the influencing factors.
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Neurodegenerative disorders, i.e., Alzheimer's or Parkinson's disease, involve progressive degeneration of the central nervous system, resulting in memory loss and cognitive impairment. The intensification of neurodegenerative research in recent years put some molecules into clinical trials, but still there is an urgent need to develop effective therapeutic molecules to combat these diseases. Chromone is a well-identified privileged structure for the design of well-diversified therapeutic molecules of potential pharmacological interest, particularly in the field of neurodegeneration. In this short review, we focused on the recent advancements and developments of chromones for neurodegenerative therapeutics. Different small molecules were reviewed as multi-target-directed ligands (MTDLs) with potential inhibition of AChE, BuChE, MAO-A, MAO-B, Aß plaque formation and aggregation. Recently developed MTDLs emphasized that the chromone scaffold has the potential to develop new molecules for the treatment of neurodegenerative diseases.
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The global trend is shifting toward circular economy systems. It is a sustainable environmental approach that sustains economic growth from the use of resources while minimizing environmental impacts. The multiple industrial use of microalgal biomass has received great attention due to its high content of essential nutrients and elements. Nevertheless, low biomass productivity, unbalanced carbon to nitrogen (C/N) ratio, resistant cellular constituents, and the high cost of microalgal harvesting represent the major obstacles for valorization of algal biomass. In recent years, microalgae biomass has been a candidate as a potential feedstock for different bioenergy generation processes with simultaneous treating wastewater and CO2 capture. An overview of the appealing features and needed advancements is urgently essential for microalgae-derived bioenergy generation. The present review provides a timely outlook and evaluation of biomethane production from microalgal biomass and related challenges. Moreover, the biogas recovery potential from microalgal biomass through different pretreatments and synergistic anaerobic co-digestion (AcoD) with other biowastes are evaluated. In addition, the removal of micropollutants and heavy metals by microalgal cells via adsorption and bioaccumulation in their biomass is discussed. Herein, a comprehensive review is presented about a successive high-throughput for anaerobic digestion (AD) of the microalgal biomass in order to achieve for sustainable energy source. Lastly, the valorization of the digestate from AD of microalgae for agricultural reuse is highlighted.
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Microalgas , Biocombustíveis , Biomassa , Nitrogênio , Águas ResiduáriasRESUMO
Investment in biofuels, as sustainable alternatives for fossil fuels, has gained momentum over the last decade due to the global environmental and health concerns regarding fossil fuel consumption. Hence, effective management of biofuel supply chain (BSC) components, including biomass feedstock production, biomass logistics, biofuel production in biorefineries, and biofuel distribution to consumers, is crucial in transitioning towards a low-carbon and circular economy (CE). The present study aims to render an inclusive knowledge map of the BSC-related scientific production. In this vein, a systematic review, supported by a keywords co-occurrence analysis and qualitative content analysis, was carried out on a total of 1,975 peer-reviewed journal articles in the target literature. The analysis revealed four major research hotspots in the BSC literature, namely (1) biomass-to-biofuel supply chain design and planning, (2) environmental impacts of biofuel production, (3) biomass to bioenergy, and (4) techno-economic analysis of biofuel production. Besides, the findings showed that the following subject areas of research in the BSC research community have recently attracted more attention: (i) global warming and climate change mitigation, (ii) development of the third-generation biofuels produced from algal biomass, which has recently gained momentum in the CE debate, and (iii) government incentives, pricing, and subsidizing policies. The provided insights shed light on the understanding of researchers, stakeholders, and policy-makers involved in the sustainable energy sector by outlining the main research backgrounds, developments, and tendencies within the BSC arena. Looking at the provided knowledge map, potential research directions in BSCs towards implementing the CE model, including (i) integrative policy convergence at macro, meso, and micro levels, and (ii) industrializing algae-based biofuel production towards the CE transition, were proposed.