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1.
Proc Natl Acad Sci U S A ; 120(42): e2312091120, 2023 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-37812706

RESUMEN

Metal-sulfur batteries have received great attention for electrochemical energy storage due to high theoretical capacity and low cost, but their further development is impeded by low sulfur utilization, poor electrochemical kinetics, and serious shuttle effect of the sulfur cathode. To avoid these problems, herein, a triple-synergistic small-molecule sulfur cathode is designed by employing N, S co-doped hierarchical porous bamboo charcoal as a sulfur host in an aqueous Cu-S battery. Expect the enhanced conductivity and chemisorption induced by N, S synergistic co-doping, the intrinsic synergy of macro-/meso-/microporous triple structure also ensures space-confined small-molecule sulfur as high utilization reactant and effectively alleviates the volume expansion during conversion reaction. Under a further joint synergy between hierarchical structure and heteroatom doping, the resulting sulfur cathode endows the Cu-S battery with outstanding electrochemical performance. Cycled at 5 A g-1, it can deliver a high reversible capacity of 2,509.8 mAh g-1 with a good capacity retention of 97.9% after 800 cycles. In addition, a flexible hybrid pouch cell built by a small-molecule sulfur cathode, Zn anode, and gel electrolytes can firmly deliver high average operating voltage of about 1.3 V with a reversible capacity of over 2,500 mAh g-1 under various destructive conditions, suggesting that the triple-synergistic small-molecule sulfur cathode promises energetic metal-sulfur batteries.

2.
Circ Res ; 130(6): 907-924, 2022 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-35189704

RESUMEN

BACKGROUND: Acute ischemic stroke (AIS) is a leading cause of disability and mortality worldwide. Prediction of penumbra existence after AIS is crucial for making decision on reperfusion therapy. Yet a fast, inexpensive, simple, and noninvasive predictive biomarker for the poststroke penumbra with clinical translational potential is still lacking. We aim to investigate whether the CircOGDH (circular RNA derived from oxoglutarate dehydrogenase) is a potential biomarker for penumbra in patients with AIS and its role in ischemic neuronal damage. METHODS: CircOGDH was screened from penumbra of middle cerebral artery occlusion mice and was assessed in plasma of patients with AIS by quantitative polymerase chain reaction. Magnetic resonance imaging was used to examine the penumbra volumes. CircOGDH interacted with miR-5112 (microRNA-5112) in primary cortical neurons was detected by fluorescence in situ hybridization, RNA immunoprecipitation, and luciferase reporter assay. Adenovirus-mediated CircOGDH knockdown ameliorated neuronal apoptosis induced by COL4A4 (Gallus collagen, type IV, alpha IV) overexpression. Transmission electron microscope, nanoparticle tracking analysis, and Western blot were performed to confirm exosomes. RESULTS: CircOGDH expression was dramatically and selectively upregulated in the penumbra tissue of middle cerebral artery occlusion mice and in the plasma of 45 patients with AIS showing a 54-fold enhancement versus noncerebrovascular disease controls. Partial regression analysis revealed that CircOGDH expression was positively correlated with the size of penumbra in patients with AIS. Sequestering of miR-5112 by CircOGDH enhanced COL4A4 expression to elevate neuron damage. Additionally, knockdown of CircOGDH significantly enhanced neuronal cell viability under ischemic conditions. Furthermore, the expression of CircOGDH in brain tissue was closely related to that in the serum of middle cerebral artery occlusion mice. Finally, we found that CircOGDH was highly expressed in plasma exosomes of patients with AIS compared with those in noncerebrovascular disease individuals. CONCLUSIONS: These results demonstrate that CircOGDH is a potential therapeutic target for regulating ischemia neuronal viability, and is enriched in neuron-derived exosomes in the peripheral blood, exhibiting a predictive biomarker of penumbra in patients with AIS.


Asunto(s)
Isquemia Encefálica , Accidente Cerebrovascular Isquémico , MicroARNs , ARN Circular/genética , Accidente Cerebrovascular , Animales , Biomarcadores , Isquemia Encefálica/genética , Isquemia Encefálica/terapia , Humanos , Hibridación Fluorescente in Situ , Infarto de la Arteria Cerebral Media/complicaciones , Infarto de la Arteria Cerebral Media/genética , Infarto de la Arteria Cerebral Media/terapia , Ratones , MicroARNs/metabolismo , Accidente Cerebrovascular/genética , Accidente Cerebrovascular/terapia
3.
J Org Chem ; 89(10): 7286-7294, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38696309

RESUMEN

Here we report a carbene-catalyzed enantio- and diastereoselective [4+2] cycloaddition reaction of cyclobutenones with isatins for the quick and efficient synthesis of spirocyclic δ-lactones bearing a chiral chlorine. A broad range of substrates with various substitution patterns proceed smoothly in this reaction, with the spirooxindole δ-lactone products afforded in generally good to excellent yields and optical purities under mild reaction conditions.

4.
J Phys Chem A ; 128(17): 3408-3418, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38651293

RESUMEN

We present a relativistic equation-of-motion coupled-cluster with single and double excitation formalism within the exact two-component framework (X2C-EOM-CCSD), where both scalar relativistic effects and spin-orbit coupling are variationally included at the reference level. Three different molecular mean-field treatments of relativistic corrections, including the one-electron, Dirac-Coulomb, and Dirac-Coulomb-Breit Hamiltonian, are considered in this work. Benchmark calculations include atomic excitations and fine-structure splittings arising from spin-orbit coupling. Comparison with experimental values and relativistic time-dependent density functional theory is also carried out. The computation of the oscillator strength using the relativistic X2C-EOM-CCSD approach allows for studies of spin-orbit-driven processes, such as the spontaneous phosphorescence lifetime.

5.
J Integr Neurosci ; 23(3): 52, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38538217

RESUMEN

BACKGROUND: A hospital-based case-control study was carried out to elucidate the association of Matrix metalloproteinase-2 (MMP-2) gene candidate polymorphisms with the susceptibility to Alzheimer's disease (AD) in the Chinese Han population. METHODS: A total of 200 AD cases and an equal number of healthy controls were recruited to undergo genotyping of specific loci within the MMP-2 gene loci (rs243866, rs2285053, rs243865). Logistic regression analysis was applied to examine the association of the genotypes and alleles of MMP-2 gene polymorphisms with AD after adjusting clinical confounding factors. RESULTS: Within AD group, a high proportion of rs243866 genotype carriers were found, and the difference remained significant despite adjusting for other clinical indicators. Among individuals with the rs243866 AA genotype and rs243865 TT genotype, the onset age of AD occurred at a younger age. Early-onset AD risk in rs243866 AA genotype carriers was 6.528 times higher than those in GG genotype carriers, and individuals with rs243865 TT genotype faced a 4.048-fold increased risk compared to those with CC genotype. CONCLUSIONS: MMP-2 gene rs243866 and rs243865 polymorphisms were closely associated with the onset age of AD. The presence of rs243866 AA genotype emerged as a crucial predictor of AD risk.


Asunto(s)
Enfermedad de Alzheimer , Metaloproteinasa 2 de la Matriz , Humanos , Metaloproteinasa 2 de la Matriz/genética , Predisposición Genética a la Enfermedad , Estudios de Casos y Controles , Enfermedad de Alzheimer/genética , Polimorfismo de Nucleótido Simple
6.
Stroke ; 54(6): 1636-1644, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37051909

RESUMEN

BACKGROUND: The soft regions of a thrombus tend to be more susceptible to r-tPA (recombinant tissue-type plasminogen activator)-mediated thrombolysis and are more easily removed by mechanical thrombectomy than the stiff counterpart. This study aimed to understand the molecular pathological differences between the soft and stiff regions of human arterial thrombus. METHODS: We developed a spatial proteomic workflow combining proteomics with laser-captured microdissection to analyze human arterial thrombi with Masson trichrome staining to identify stiff and soft regions from 2 independent cohorts of patients with acute myocardial or cerebral infarction. Dysregulated proteins in a C57BL6/J male mouse model of arterial thrombosis were identified by pathway enrichment and pairwise analyses from the common gene ontology enrichment and dysregulated proteins between carotid and coronary arterial thrombi, and validated by immunohistochemistry. RESULTS: Spatial proteomics of the coronary arterial thrombi collected from 7 patients with myocardial infarct revealed 7 common dysregulated proteins in 2 cohorts of patients, and upregulation of TGF-ß1 (transforming growth factor ß1) was the most prominent fibrosis-related protein. Inhibition of TGF-ß1 resulted in delayed arterial thrombosis and accelerated blood flow restoration in mouse model. We further expanded the spatial proteomic workflow to the carotid artery thrombi collected from 11 patients with cerebral infarction. Pairwise proteomic analysis of stiff and soft regions between carotid and coronary arterial thrombi further revealed 5 common gene ontology clusters including features of platelet activation, and a common dysregulated protein COL1A1 (collagen type 1 alpha 1) that was reported to be influenced by TGF-ß1. We also verified the expression in human and mice carotid arterial thrombi. CONCLUSIONS: This study demonstrates the spatially distinct composition of proteins in the stiff and soft regions of human arterial thrombi, and suggests that TGF-ß1 is a key therapeutic target for promoting arterial thrombolysis.


Asunto(s)
Infarto del Miocardio , Trombosis , Humanos , Masculino , Animales , Ratones , Factor de Crecimiento Transformador beta1 , Proteómica , Trombosis/patología , Infarto del Miocardio/metabolismo , Infarto Cerebral
7.
Small ; 19(47): e2301671, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37491784

RESUMEN

Mesenchymal stem cell (MSC)-based therapies are increasingly recognized as promising cellular therapeutics and show the ability to treat various diseases. However, the underlying mechanism is not fully elucidated. Some recent studies have shown an unexpected result whereby MSCs undergo rapid apoptosis following administration but still exert therapeutic effects in some disease treatments. Such a therapeutic mechanism is believed to associate with the released apoptotic vesicles from apoptotic MSCs (MSC-ApoVs). This finding inspires a novel therapeutic strategy for using MSC-ApoVs for disease treatment. The present review aims to summarize the biogenesis, physiological functions, therapeutic potentials, and related mechanisms of apoptotic vesicles in MSC-based therapy. In addition, the potential applications of MSC-ApoVs as natural therapeutic agents and natural drug delivery vehicles are proposed and highlighted. The present review is hoped to provide a general understanding of MSC-ApoVs in disease treatment and inspire potential applications in targeted drug delivery.


Asunto(s)
Sistemas de Liberación de Medicamentos , Vesículas Extracelulares , Células Madre Mesenquimatosas
8.
Appl Environ Microbiol ; 89(10): e0060523, 2023 10 31.
Artículo en Inglés | MEDLINE | ID: mdl-37800969

RESUMEN

The long-read amplicon provides a species-level solution for the community. With the improvement of nanopore flowcells, the accuracy of Oxford Nanopore Technologies (ONT) R10.4.1 has been substantially enhanced, with an average of approximately 99%. To evaluate its effectiveness on amplicons, three types of microbiomes were analyzed by 16S ribosomal RNA (hereinafter referred to as "16S") amplicon sequencing using Novaseq, Pacbio sequel II, and Nanopore PromethION platforms (R9.4.1 and R10.4.1) in the current study. We showed the error rate, recall, precision, and bias index in the mock sample. The error rate of ONT R10.4.1 was greatly reduced, with a better recall in the case of the synthetic community. Meanwhile, in different types of environmental samples, ONT R10.4.1 analysis resulted in a composition similar to Pacbio data. We found that classification tools and databases influence ONT data. Based on these results, we conclude that the ONT R10.4.1 16S amplicon can also be used for application in environmental samples. IMPORTANCE The long-read amplicon supplies the community with a species-level solution. Due to the high error rate of nanopore sequencing early on, it has not been frequently used in 16S studies. Oxford Nanopore Technologies (ONT) introduced the R10.4.1 flowcell with Q20+ reagent to achieve more than 99% accuracy as sequencing technology advanced. However, there has been no published study on the performance of commercial PromethION sequencers with R10.4.1 flowcells on 16S sequencing or on the impact of accuracy improvement on taxonomy (R9.4.1 to R10.4.1) using 16S ONT data. In this study, three types of microbiomes were investigated by 16S ribosomal RNA (rRNA) amplicon sequencing using Novaseq, Pacbio sequel II, and Nanopore PromethION platforms (R9.4.1 and R10.4.1). In the mock sample, we displayed the error rate, recall, precision, and bias index. We observed that the error rate in ONT R10.4.1 is significantly lower, especially when deletions are involved. First and foremost, R10.4.1 and Pacific Bioscience platforms reveal a similar microbiome in environmental samples. This study shows that the R10.4.1 full-length 16S rRNA sequences allow for species identification of environmental microbiota.


Asunto(s)
Microbiota , Nanoporos , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN/métodos , Microbiota/genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos
9.
Cell Mol Neurobiol ; 43(2): 859-878, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35449428

RESUMEN

The prognosis of ischemic stroke patients is highly associated with the collateral circulation. And the competing endogenous RNAs (ceRNAs) generated from different compensatory supply regions may also involve in the regulation of ischemic tissues prognosis. In this study, we found the apoptosis progress of ischemic neurons in posterior circulation-supplied regions (close to PCA, cortex2) was much slower than that in anterior circulation-supplied territory (close to ACA, cortex1) in MCAO-3-h mice. Using the RNA sequencing and functional enrichment analysis, we analyzed the difference between RNA expression profile in cortex1 and cortex2 and the related biological processes. The results indicated that the differential expressed ceRNAs in cortex1 were involved in cell process under acute injury, while the differential expressed ceRNAs in cortex2 was more likely to participate in long-term injury and repair process. Besides, by establishing the miRNA-ceRNA interaction network we further sorted out two specifically distributed miRNAs, namely mmu-miR446i-3p (in cortex1) and mmu-miR3473d (in cortex2). And the specifically increased mmu-miR3473d in cortex2 mainly involved the angiogenesis and cell proliferation after ischemic stroke, which may be the critical reason for the longer therapeutic time window in cortex2. In conclusion, the present study reported the specific changes of ceRNAs in distinct compensatory regions potentially involved in the evolution of cerebral ischemic tissues and the unbalance prognosis after stroke. It provided more evidence for the collateral compensatory effects on patients' prognosis and carried out the new targets for the ischemic stroke therapy.


Asunto(s)
Accidente Cerebrovascular Isquémico , MicroARNs , ARN Largo no Codificante , Accidente Cerebrovascular , Animales , Ratones , Regulación Neoplásica de la Expresión Génica , MicroARNs/genética , Accidente Cerebrovascular/genética , Accidente Cerebrovascular Isquémico/genética , ARN Largo no Codificante/genética , Redes Reguladoras de Genes
10.
Mol Pharm ; 20(9): 4354-4372, 2023 09 04.
Artículo en Inglés | MEDLINE | ID: mdl-37566627

RESUMEN

Cardiovascular diseases (CVDs) are the leading cause of human death worldwide. Exosomes act as endogenous biological vectors; they possess advantages of low immunogenicity and low safety risks, also providing tissue selectivity, including the inherent targeting the to heart. Therefore, exosomes not only have been applied as biomarkers for diagnosis and therapeutic outcome confirmation but also showed potential as drug carriers for cardiovascular targeting delivery. This review aims to summarize the progress and challenges of exosomes as novel biomarkers, especially many novel exosomal noncoding RNAs (ncRNAs), and also provides an overview of the improved targeting functions of exosomes by unique engineered approaches, the latest developed administration methods, and the therapeutic effects of exosomes used as the biocarriers of medications for cardiovascular disease treatment. Also, the possible therapeutic mechanisms and the potentials for transferring exosomes to the clinic for CVD treatment are discussed. The advances, in vivo and in vitro applications, modifications, mechanisms, and challenges summarized in this review will provide a general understanding of this promising strategy for CVD treatment.


Asunto(s)
Enfermedades Cardiovasculares , Exosomas , Humanos , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/tratamiento farmacológico , Portadores de Fármacos , Corazón , Biomarcadores
11.
J Org Chem ; 88(22): 15894-15901, 2023 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-37933141

RESUMEN

A novel tactic to synthesize unsymmetrical 3-aryladipic acid esters has been developed via magnesium-promoted reductive coupling of ethyl cinnamates with methyl acrylate. In the present methodology, 3-aryladipic acid derivatives were prepared with good functional group tolerance and a wide substrate scope under very mild reaction conditions in good yields. The application of this reaction to dienic acid esters led to the successful control of the reaction to give 5-aryl-oct-3-enedioic acid esters with high regioselectivity.

12.
Environ Sci Technol ; 57(2): 1144-1156, 2023 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-36599031

RESUMEN

Conventional phototrophic cultivation for microalgae production suffers from low and unstable biomass productivity due to limited and unreliable light transmission outdoors. Alternatively, the use of a renewable lignocellulose-derived carbon source, cellulosic hydrolysate, offers a cost-effective and sustainable pathway to cultivate microalgae heterotrophically with high algal growth rate and terminal density. In this study, we evaluate the feasibility of cellulosic hydrolysate-mediated heterotrophic cultivation (Cel-HC) for microalgae production by performing economic and environmental comparisons with phototrophic cultivation through techno-economic analysis and life cycle assessment. We estimate a minimum selling price (MSP) of 4722 USD/t for producing high-purity microalgae through Cel-HC considering annual biomass productivity of 300 t (dry weight), which is competitive with the conventional phototrophic raceway pond system. Revenues from the lignocellulose-derived co-products, xylose and fulvic acid fertilizer, could further reduce the MSP to 2976 USD/t, highlighting the advantages of simultaneously producing high-value products and biofuels in an integrated biorefinery scheme. Further, Cel-HC exhibits lower environmental impacts, such as cumulative energy demand and greenhouse gas emissions, than phototrophic systems, revealing its potential to reduce the carbon intensity of algae-derived commodities. Our results demonstrate the economic and environmental competitiveness of heterotrophic microalgae production based on renewable bio-feedstock of lignocellulose.


Asunto(s)
Microalgas , Microalgas/metabolismo , Lignina/metabolismo , Biocombustibles , Biomasa , Carbono/metabolismo
13.
J Chem Phys ; 159(4)2023 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-37497820

RESUMEN

Simulations of laser-induced electron dynamics in a molecular system are performed using time-dependent (TD) equation-of-motion (EOM) coupled-cluster (CC) theory. The target system has been chosen to highlight potential shortcomings of truncated TD-EOM-CC methods [represented in this work by TD-EOM-CC with single and double excitations (TD-EOM-CCSD)], where unphysical spectroscopic features can emerge. Specifically, we explore driven resonant electronic excitations in magnesium fluoride in the proximity of an avoided crossing. Near the avoided crossing, the CCSD similarity-transformed Hamiltonian is defective, meaning that it has complex eigenvalues, and oscillator strengths may take on negative values. When an external field is applied to drive transitions to states exhibiting these traits, unphysical dynamics are observed. For example, the stationary states that make up the time-dependent state acquire populations that can be negative, exceed one, or even complex-valued.

14.
J Chem Phys ; 159(11)2023 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-37728204

RESUMEN

In this study, we present an efficient integral decomposition approach called the restricted-kinetic-balance resolution-of-the-identity (RKB-RI) algorithm, which utilizes a tunable RI method based on the Cholesky integral decomposition for in-core relativistic quantum chemistry calculations. The RKB-RI algorithm incorporates the restricted-kinetic-balance condition and offers a versatile framework for accurate computations. Notably, the Cholesky integral decomposition is employed not only to approximate symmetric large-component electron repulsion integrals but also those involving small-component basis functions. In addition to comprehensive error analysis, we investigate crucial conditions, such as the kinetic balance condition and variational stability, which underlie the applicability of Dirac relativistic electronic structure theory. We compare the computational cost of the RKB-RI approach with the full in-core method to assess its efficiency. To evaluate the accuracy and reliability of the RKB-RI method proposed in this work, we employ actinyl oxides as benchmark systems, leveraging their properties for validation purposes. This investigation provides valuable insights into the capabilities and performance of the RKB-RI algorithm and establishes its potential as a powerful tool in the field of relativistic quantum chemistry.

15.
J Chem Phys ; 158(17)2023 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-37139994

RESUMEN

Variational treatment of the Dirac-Coulomb-Gaunt or Dirac-Coulomb-Breit two-electron interaction at the Dirac-Hartree-Fock level is the starting point of high-accuracy four-component calculations of atomic and molecular systems. In this work, we introduce, for the first time, the scalar Hamiltonians derived from the Dirac-Coulomb-Gaunt and Dirac-Coulomb-Breit operators based on spin separation in the Pauli quaternion basis. While the widely used spin-free Dirac-Coulomb Hamiltonian includes only the direct Coulomb and exchange terms that resemble nonrelativistic two-electron interactions, the scalar Gaunt operator adds a scalar spin-spin term. The spin separation of the gauge operator gives rise to an additional scalar orbit-orbit interaction in the scalar Breit Hamiltonian. Benchmark calculations of Aun (n = 2-8) show that the scalar Dirac-Coulomb-Breit Hamiltonian can capture 99.99% of the total energy with only 10% of the computational cost when real-valued arithmetic is used, compared to the full Dirac-Coulomb-Breit Hamiltonian. The scalar relativistic formulation developed in this work lays the theoretical foundation for the development of high-accuracy, low-cost correlated variational relativistic many-body theory.

16.
Eur Spine J ; 32(4): 1153-1160, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36809342

RESUMEN

PURPOSE: To investigate lowest instrumented vertebra (LIV) selection strategy for neurofibromatosis type 1 (NF-1) non-dystrophic scoliosis. METHODS: Consecutive eligible subjects with NF-1 non-dystrophic scoliosis were included. All patients were followed up at least for 24 months. Enrolled patients with LIV in stable vertebra were divided into stable vertebra group (SV group), and the other patients with LIV above the stable vertebra were divided into above stable vertebra group (ASV group). Demographic data, operative data, preoperative and postoperative radiographic data, and clinical outcome were collected and analyzed. RESULTS: There were 14 patients in SV group (ten males and four females, mean age 13.9 ± 4.1 years) and 14 patients in ASV group (nine males and five females, mean age 12.9 ± 3.5 years). The mean follow-up period was 31.7 ± 17.4 months for patients in SV group and 33.6 ± 17.4 months for patients in ASV group, respectively. No significant differences were found in demographic data between two groups. The coronal Cobb angle, C7-CSVL, AVT, LIVDA, LIV tilt and SRS-22 questionnaire outcome significantly improved at the final follow-up in both groups. However, significantly higher loss of correction rate and increasement of LIVDA were found in ASV group. Two patients (14.3%) in ASV group but none in SV group suffered adding-on phenomenon. CONCLUSIONS: Although patients in both SV and ASV groups obtained improved therapeutic efficacy at final follow-up, the radiographic and clinical outcome seemed more likely to deteriorate in ASV group after surgery. The stable vertebra should be recommended as LIV for NF-1 non-dystrophic scoliosis.


Asunto(s)
Neurofibromatosis 1 , Escoliosis , Fusión Vertebral , Masculino , Femenino , Humanos , Niño , Adolescente , Escoliosis/diagnóstico por imagen , Escoliosis/cirugía , Vértebras Torácicas/cirugía , Vértebras Lumbares/cirugía , Radiografía , Estudios Retrospectivos , Resultado del Tratamiento , Estudios de Seguimiento
17.
J Environ Manage ; 338: 117744, 2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-37003221

RESUMEN

Energy and water resources are closely linked in electric power systems, and the application of low-carbon technologies further affects electricity generation and water consumption in those systems. The holistic optimization of electric power systems, including generation and decarbonization processes, is necessary. Few studies have considered the uncertainty associated with the application of low-carbon technologies in electric power systems optimization from an energy-water nexus perspective. To fill such a gap, this study developed a simulation-based low-carbon energy structure optimization model to address the uncertainty in power systems with low-carbon technologies and generate electricity generation plans. Specifically, LMDI, STIRPAT and grey model were integrated to simulate the carbon emissions from the electric power systems under different socio-economic development levels. Furthermore, a copula-based chance-constrained interval mixed-integer programming model was proposed to quantify the energy-water nexus as the joint violation risk and generate risk-based low-carbon generation schemes. The model was applied to support the management of electric power systems in the Pearl River Delta of China. Results indicate that, the optimized plans could mitigate CO2 emission by up to 37.93% over 15 years. Under all scenarios, more low-carbon power conversion facilities would be established. The application of carbon capture and storage would increase energy and water consumption by up to [0.24, 7.35] × 106 tce and [0.16, 1.12] × 108 m3, respectively. The optimization of the energy structure based on energy-water joint violation risk could reduce the water utilization rate and the carbon emission rate by up to 0.38 m3/104 kWh and 0.04 ton-CO2/104 kWh, respectively.


Asunto(s)
Carbono , Agua , Carbono/análisis , Dióxido de Carbono/análisis , Recursos Hídricos , Electricidad , China
18.
J Environ Manage ; 329: 116996, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36535143

RESUMEN

A critical step in water management policy development is the analysis of its socio-economic and environmental implications. However, few methods could proactively and reliably predict and assess the impacts of policies while handling the inherent uncertainty. To fill such a gap, an inexact simulation-evaluation method was developed for analyzing the impacts of multiple water management policies under uncertainty. The interval positive mathematical programming (IPMP) method was proposed as the simulation tool by coupling interval programming with positive mathematical programming (PMP). The evaluation tool was developed by combining the interval TOPSIS method and the interval maximum deviation method. This simulation-evaluation method can directly communicate a policy's simulation outcomes into the evaluation process while addressing the uncertainties in both simulation and evaluation. The proposed method can also reproduce the actual situation with a calibration process, which enables accurate and smooth responses to policy changes. This approach was used for agricultural water management in arid north-west China. Seventy-five policy alternatives generated from three groundwater allocation limits and twenty-five differential water pricing levels were investigated. The impacts of these alternatives on farmer income, farmer employment, water consumption, planting areas, and fertilizer use were simulated using IPMP. Twenty-four non-inferior alternatives were selected and further evaluated with multi-dimensional criteria. The final results showed that, the water price for grain crops with traditional irrigation methods should rise by 60%, those for cash crops with drip irrigation should decrease by 60%, and the groundwater quota should be reduced by 20%. Compared with traditional models, IPMP can increase simulation accuracy by reproducing observed situations, enhance robustness by reflecting input uncertainty, and improve flexibility in decision-making by providing interval solutions. The inexact simulation-evaluation model can also be widely used to analyze other policies.


Asunto(s)
Agua Subterránea , Agua , Modelos Teóricos , Incertidumbre , Costos y Análisis de Costo
19.
J Org Chem ; 87(11): 7342-7349, 2022 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-35608163

RESUMEN

Direct reductive carboxylation of easily prepared aryl vinyl ketones under the atmosphere of carbon dioxide led to the selective formation of γ-keto carboxylic acids in 38-86% yields. The reaction is characterized by the carbon-carbon bond formation of carbon dioxide at the ß-position of enone, with the use of magnesium turnings that can be easily handled as the reducing agent and the eco-friendly reaction conditions such as no pressuring, no lower or higher reaction temperature, and short reaction time. This protocol showed a wide substrate scope and provided a useful and convenient alternative to access biologically important γ-keto carboxylic acids.

20.
Bioorg Med Chem Lett ; 69: 128798, 2022 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-35580725

RESUMEN

The success of stem cells therapy to treat neurodegenerative diseases is currently restricted by the lack of suitable stem cells. Mesenchymal stem cells (MSCs) have demonstrated several advantages as seed-cells for the stem cells therapy. In particular, the low immunogenicity and multiple lineages differentiation capability enables the possibility of using MSCs to treat neurodegenerative diseases. However, a more potent neuronal differentiation capacity of MSCs is required during a success treatment against neurodegenerative diseases. Bioengineering using small molecules to boost the neuronal differentiation of MSCs has been proposed as a promising strategy. Herein, we developed a new series of (2-phenylthiazol-4-yl)urea derivatives and one of them, 18g were observed to successfully promote neuronal differentiation of MSCs after culturing MSCs with 18g for 4 days. In addition, neither significant cytotoxicity nor cell cycle altering were found after the incubation. Interestingly, the osteogenic differentiation potential of MSCs was not affected after 18g treatment. The present study provides a promising small molecule to boost the innate neuronal differentiation capacity of MSCs with no serious detrimental effects.


Asunto(s)
Células Madre Mesenquimatosas , Enfermedades Neurodegenerativas , Diferenciación Celular , Células Cultivadas , Humanos , Enfermedades Neurodegenerativas/metabolismo , Osteogénesis , Urea/metabolismo , Urea/farmacología
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