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1.
Bioresour Technol ; 402: 130838, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38740312

RESUMO

Stochastic and deterministic processes are the major themes governing microbial community assembly; however, their roles in bioreactors are poorly understood. Herein, the mechanisms underlying microbial assembly and the effect of rare taxa were studied in biofilters. Phylogenetic tree analysis revealed differences in microbial communities at various stages. Null model analysis showed that stochastic processes shaped the community assembly, and deterministic processes emerged only in the inoculated activated sludge after domestication. This finding indicates the dominant role of stochastic factors (biofilm formation, accumulation, and aging). The Sloan neutral model corroborated the advantages of stochastic processes and mainly attributed these advantages to rare taxa. Cooccurrence networks revealed the importance of rare taxa, which accounted for more than 85% of the keystones. Overall, these results provide good foundations for understanding community assembly, especially the role of rare taxa, and offer theoretical support for future community design and reactor regulation.

2.
Org Lett ; 26(20): 4205-4211, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38743606

RESUMO

An unprecedented base-controlled selective skeletal rearrangement reaction of hexahydro-4H-indol-4-ones has been developed. In this protocol, highly functionalized dihydroxy-4H-cyclopenta[b]pyridin-4-ones and 8-alkenyl oxepane-2,6-diones were prepared with a broad substrate scope and high chemoselectivity in moderate to excellent yields selectively by modulating LiOH and Et3N. In addition, the newly formed 8-alkenyl oxepane-2,6-dione scaffolds could be easily further derivatized to 5-(pyrrol-2-yl)dihydrofuran-2(3H)-ones through a rare intramolecular rearrangement reaction.

3.
Sci Total Environ ; 927: 172376, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38604376

RESUMO

Biofilms are widely used and play important roles in biological processes. Low temperature of wastewater inhibits the development of biofilms derived from wastewater activated sludge. However, the specific mechanism of temperature on biofilm development is still unclear. This study explored the mechanism of temperature on biofilm development and found a feasible method to enhance biofilm development at low temperature. The amount of biofilm development decreased by approximately 66 % and 55 % at 4 °C and 15 °C, respectively, as compared to 28 °C. The cyclic dimeric guanosine monophosphate (c-di-GMP) concentration also decreased at low temperature and was positively correlated with extracellular polymeric substance (EPS) content, formation, and adhesion strength. Microbial community results showed that low temperature inhibited the normal survival of most microorganisms, but promoted the growth of some psychrophile bacteria like Sporosarcina, Caldilineaceae, Gemmataceae, Anaerolineaceae and Acidobacteriota. Further analysis of functional genes demonstrated that the abundance of functional genes related to the synthesis of c-di-GMP (K18968, K18967 and K13590) decreased at low temperature. Subsequently, the addition of exogenous spermidine increased the level of intracellular c-di-GMP and alleviated the inhibition effect of low temperature on biofilm development. Therefore, the possible mechanism of low temperature on biofilm development could be the inhibition of the microorganism activity and reduction of the communication level between cells, which is the closely related to the EPS content, formation, and adhesion strength. The enhancement of c-di-GMP level through the exogenous addition of spermidine provides an alternative strategy to enhance biofilm development at low temperatures. The results of this study enhance the understanding of the influence of temperature on biofilm development and provide possible strategies for enhancing biofilm development at low temperatures.


Assuntos
Bactérias , Biofilmes , GMP Cíclico , Fenômenos Fisiológicos Bacterianos , Temperatura Baixa , GMP Cíclico/análogos & derivados , GMP Cíclico/metabolismo , Matriz Extracelular de Substâncias Poliméricas , Águas Residuárias/microbiologia
4.
Nat Commun ; 15(1): 3399, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649376

RESUMO

The van der Waals antiferromagnetic topological insulator MnBi2Te4 represents a promising platform for exploring the layer-dependent magnetism and topological states of matter. Recently observed discrepancies between magnetic and transport properties have aroused controversies concerning the topological nature of MnBi2Te4 in the ground state. In this article, we demonstrate that fabrication can induce mismatched even-odd layer dependent magnetotransport in few-layer MnBi2Te4. We perform a comprehensive study of the magnetotransport properties in 6- and 7-septuple-layer MnBi2Te4, and reveal that both even- and odd-number-layer device can show zero Hall plateau phenomena in zero magnetic field. Importantly, a statistical survey of the optical contrast in more than 200 MnBi2Te4 flakes reveals that the zero Hall plateau in odd-number-layer devices arises from the reduction of the effective thickness during the fabrication, a factor that was rarely noticed in previous studies of 2D materials. Our finding not only provides an explanation to the controversies regarding the discrepancy of the even-odd layer dependent magnetotransport in MnBi2Te4, but also highlights the critical issues concerning the fabrication and characterization of 2D material devices.

5.
JACS Au ; 4(4): 1591-1604, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38665654

RESUMO

P450 NascB catalyzes the coupling of cyclo-(l-tryptophan-l-proline) (1) to generate (-)-naseseazine C (2) through intramolecular C-N bond formation and intermolecular C-C coupling. A thorough understanding of its catalytic mechanism is crucial for the engineering or design of P450-catalyzed C-N dimerization reactions. By employing MD simulations, QM/MM calculations, and enhanced sampling, we assessed various mechanisms from recent works. Our study demonstrates that the most favorable pathway entails the transfer of a hydrogen atom from N7-H to Cpd I. Subsequently, there is a conformational change in the substrate radical, shifting it from the Re-face to the Si-face of N7 in Substrate 1. The Si-face conformation of Substrate 1 is stabilized by the protein environment and the π-π stacking interaction between the indole ring and heme porphyrin. The subsequent intermolecular C3-C6' bond formation between Substrate 1 radical and Substrate 2 occurs via a radical attack mechanism. The conformational switch of the Substrate 1 radical not only lowers the barrier of the intermolecular C3-C6' bond formation but also yields the correct stereoselectivity observed in experiments. In addition, we evaluated the reactivity of the ferric-superoxide species, showing it is not reactive enough to initiate the hydrogen atom abstraction from the indole NH group of the substrate. Our simulation provides a comprehensive mechanistic insight into how the P450 enzyme precisely controls both the intramolecular C-N cyclization and intermolecular C-C coupling. The current findings align with the available experimental data, emphasizing the pivotal role of substrate dynamics in governing P450 catalysis.

6.
Biomimetics (Basel) ; 9(4)2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38667223

RESUMO

With the rise and development of autonomy and intelligence technologies, UAVs will have increasingly significant applications in the future. It is very important to solve the problem of low-altitude penetration of UAVs to protect national territorial security. Based on an S-57 electronic chart file, the land, island, and threat information for an actual combat environment is parsed, extracted, and rasterized to construct a marine combat environment for UAV flight simulation. To address the problem of path planning for low-altitude penetration in complex environments, a photosensitivity-enhanced plant growth algorithm (PEPG) is proposed. Based on the plant growth path planning algorithm (PGPP), the proposed algorithm improves upon the light intensity preprocessing and light intensity calculation methods. Moreover, the kinematic constraints of the UAV, such as the turning angle, are also considered. The planned path that meets the safety flight requirements of the UAV is smoother than that of the original algorithm, and the length is reduced by at least 8.2%. Finally, simulation tests are carried out with three common path planning algorithms, namely, A*, RRT, and GA. The results show that the PEPG algorithm is superior to the other three algorithms in terms of the path length and path quality, and the feasibility and safety of the path are verified via the autonomous tracking flight of a UAV.

7.
Molecules ; 29(8)2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38675610

RESUMO

A chemselective catalyst-free three-component 1,3-dipolar cycloaddition has been described. The unique polycyclic THPI and THIQs were creatively employed as dipolarophiles, which led to the formation of functionalized ß-tetrahydrocarboline- and tetrahydroisoquinoline-fused spirooxindoles in 60-94% of yields with excellent diastereoselectivities (10: 1->99: 1 dr). This reaction not only realizes a concise THPI- or THIQs-based 1,3-dipolar cycloaddition, but also provides a practical strategy for the construction of two distinctive spirooxindole skeletons.

8.
Molecules ; 29(6)2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38543018

RESUMO

Que Zui tea (QT) is an important herbal tea in the diet of the 'Yi' people, an ethnic group in China, and it has shown significant antioxidant, anti-inflammatory, and hepatoprotective effects in vitro. This study aims to explore the protective effects of the aqueous-ethanol extract (QE) taken from QT against ᴅ-galactose (ᴅ-gal)-induced oxidative stress damage in mice and its potential mechanisms. QE was identified as UHPLC-HRMS/MS for its chemical composition and possible bioactive substances. Thus, QE is rich in phenolic and flavonoid compounds. Twelve compounds were identified, the main components of which were chlorogenic acid, quinic acid, and 6'-O-caffeoylarbutin. Histopathological and biochemical analysis revealed that QE significantly alleviated brain, liver, and kidney damage in ᴅ-gal-treated mice. Moreover, QE remarkably attenuated oxidative stress by activating the Nrf2/HO-1 pathway to increase the expression of antioxidant indexes, including GSH, GSH-Px, CAT, SOD, and T-AOC. In addition, QE administration could inhibit the IL-1ß and IL-6 levels, which suppress the inflammatory response. QE could noticeably alleviate apoptosis by inhibiting the expressions of Caspase-3 and Bax proteins in the brains, livers, and kidneys of mice. The anti-apoptosis mechanism may be related to the upregulation of the SIRT1 protein and the downregulation of the p53 protein induced by QE in the brain, liver, and kidney tissues of mice. Molecular docking analysis demonstrated that the main components of QE, 6'-O-caffeoylarbutin, chlorogenic acid, quinic acid, and robustaside A, had good binding ability with Nrf2 and SIRT1 proteins. The present study indicated that QE could alleviate ᴅ-gal-induced brain, liver and kidney damage in mice by inhibiting the oxidative stress and cell apoptosis; additionally, the potential mechanism may be associated with the SIRT1/Nrf2 signaling pathway.


Assuntos
Antioxidantes , Arbutina/análogos & derivados , Ácidos Cafeicos , Galactose , Humanos , Camundongos , Animais , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Galactose/efeitos adversos , Fator 2 Relacionado a NF-E2/metabolismo , Sirtuína 1/metabolismo , Ácido Clorogênico/farmacologia , Simulação de Acoplamento Molecular , Ácido Quínico/farmacologia , Estresse Oxidativo , Transdução de Sinais , Chá
9.
Front Immunol ; 15: 1322125, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38440735

RESUMO

Introduction: One rare type of autoimmune disease is called neuromyelitis optica spectrum disorder (NMOSD) and the peripheral immune characteristics of NMOSD remain unclear. Methods: Here, single-cell RNA sequencing (scRNA-seq) is used to characterize peripheral blood mononuclear cells from individuals with NMOSD. Results: The differentiation and activation of lymphocytes, expansion of myeloid cells, and an excessive inflammatory response in innate immunity are observed. Flow cytometry analyses confirm a significant increase in the percentage of plasma cells among B cells in NMOSD. NMOSD patients exhibit an elevated percentage of CD8+ T cells within the T cell population. Oligoclonal expansions of B cell receptors are observed after therapy. Additionally, individuals with NMOSD exhibit elevated expression of CXCL8, IL7, IL18, TNFSF13, IFNG, and NLRP3. Discussion: Peripheral immune response high-dimensional single-cell profiling identifies immune cell subsets specific to a certain disease and identifies possible new targets for NMOSD.


Assuntos
Doenças Autoimunes , Neuromielite Óptica , Humanos , Leucócitos Mononucleares , Neuromielite Óptica/genética , Processos de Crescimento Celular , Análise de Sequência de RNA
10.
Front Cardiovasc Med ; 11: 1324456, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38404724

RESUMO

Objective: Assessing the impact of lumbar disc herniation (LDH) on the plaque burden of coronary atherosclerosis is our objective. Methods: In this study, a total of 212 patients (age 46-80 years) with unstable angina (UA) who underwent coronary angiography (CAG) in our hospital from January 2018 to July 2022 due to UA were included. Patients were divided into LDH group (n = 106) and no LDH group (n = 106). Gensini scores were calculated to assess the plaque burden of coronary. Logistic analysis was used to examine potential risk variables linked to the Gensini score. The association between lumbar disc lesions grading and coronary plaque burden was analysed by Spearman's correlation test. LDH patients with higher plaque burden (n = 56) were further divided into evolocumab treatment group (n = 28) and conventional treatment group (n = 28). Cox regression analysis were performed. Results: Patients with LDH had higher Gensini scores (P < 0.01) and triglyceride (TG) levels (P = 0.04), but HDL-C (P = 0.01) levels were lower. LDH was found to be an independent risk factor for higher Gensini scores (OR = 2.38, P < 0.01) by logistic analysis. The Spearman's correlation test suggested that the degree of lumbar disc lesions was related to the Gensini score and the level of blood lipid. Cox regression analysis showed that evolocumab treatment could significantly reduce the composite MACE events (cardiac death, nonfatal myocardial infarction, nonfatal stroke, and readmission due to angina) (HR = 0.26, P = 0.04) in higher coronary plaque burden patients. Conclusion: LDH is an independent risk factor for the higher coronary plaque burden. Evolocumab treatment significantly reduced the occurrence of cardiovascular events in LDH patients with higher plaque burden. Additionally, our data indicate that LDH is associated with increased blood lipid, which may contribute to the development of plaque burden.

11.
ACS Nano ; 18(9): 6946-6962, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38377037

RESUMO

Pyroptosis mediated by gasdermin protein has shown great potential in cancer immunotherapies. However, the low expression of gasdermin proteins and the systemic toxicity of nonspecific pyroptosis limit its clinical application. Here, we designed a synthetic biology strategy to construct a tumor-specific pyroptosis-inducing nanoplatform M-CNP/Mn@pPHS, in which a pyroptosis-inducing plasmid (pPHS) was loaded onto a manganese (Mn)-doped calcium carbonate nanoparticle and wrapped in a tumor-derived cell membrane. M-CNP/Mn@pPHS showed an efficient tumor targeting ability. After its internalization by tumor cells, the degradation of M-CNP/Mn@pPHS in the acidic endosomal environment allowed the efficient endosomal escape of plasmid pPHS. To trigger tumor-specific pyroptosis, pPHS was designed according to the logic "AND gate circuit" strategy, with Hif-1α and Sox4 as two input signals and gasdermin D induced pyroptosis as output signal. Only in cells with high expression of Hif-1α and Sox4 simultaneously will the output signal gasdermin D be expressed. Since Hif-1α and Sox4 are both specifically expressed in tumor cells, M-CNP/Mn@pPHS induces the tumor-specific expression of gasdermin D and thus pyroptosis, triggering an efficient immune response with little systemic toxicity. The Mn2+ released from the nanoplatform further enhanced the antitumor immune response by stimulating the cGAS-STING pathway. Thus, M-CNP/Mn@pPHS efficiently inhibited tumor growth with 79.8% tumor regression in vivo. We demonstrate that this logic "AND gate circuit"-based gasdermin nanoplatform is a promising strategy for inducing tumor-specific pyroptosis with little systemic toxicity.


Assuntos
Neoplasias , Piroptose , Humanos , Gasderminas , Peptídeos e Proteínas de Sinalização Intracelular , Neoplasias/terapia , Imunoterapia , Lógica
12.
Sci Total Environ ; 918: 170628, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38325476

RESUMO

The one-time application of common urea blended with controlled-release urea (CRU) is considered effective for improving nitrogen use efficiency and grain yield and reducing the greenhouse gas emissions of summer maize in intensive agricultural systems. However, the trade-off between the economic and environmental performances of different blended fertilizer treatments for different maize varieties remains unclear. Therefore, a consecutive two-year field experiment was conducted in the North China Plain to study the effects of different ratios of CRU and common urea on the yield, nitrous oxide (N2O) emissions, yield-scaled total N2O emissions, greenhouse gas intensity (GHGI), and net ecosystem economic benefit (NEEB) in 2021 and 2022. Four N fertilizer treatments with equal rate at 180 kg N ha-1 were applied as N180U (all Urea), N180C1(1/3CRU), N180C2(2/3CRU), and N180C (all CRU), and two maize varieties (JNK728-yellow ripe variety and ZD958-green ripe variety) were used. The N180C1 and N180C2 treatments produced the highest grain yield in varieties JNK728 and ZD958 (9.4-11.5 t ha-1 and 9.0-11.0 t ha-1), respectively. Compared to the N180U treatment (conventional method), the N180C1 treatment reduced the GHGI (24.8 %-25.9 %) and increased the NEEB (33.1 %-33.4 %) in the JNK728 variety, whereas the N180C2 treatment reduced the GHGI (16.9 %-28.8 %) and increased the NEEB (27.2 %-48.1 %) in the ZD958 variety. The study concludes that a one-time application of blended nitrogen fertilizer in suitable varieties can minimize the GHGI and maximize the NEEB, which is an effective strategy for balancing yield and nitrogen efficiency in the summer maize system in the North China Plain.


Assuntos
Gases de Efeito Estufa , Gases de Efeito Estufa/análise , Solo , Zea mays , Preparações de Ação Retardada , Ureia , Fertilizantes/análise , Ecossistema , Metano/análise , Agricultura/métodos , Nitrogênio , Grão Comestível/química , Óxido Nitroso/análise , China
13.
J Control Release ; 367: 61-75, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38242210

RESUMO

Pyroptosis, mediated by gasdermin proteins, has shown excellent efficacy in facilitating cancer immunotherapy. The strategies commonly used to induce pyroptosis suffer from a lack of tissue specificity, resulting in the nonselective activation of pyroptosis and consequent systemic toxicity. Moreover, pyroptosis activation usually depends on caspase, which can induce inflammation and metabolic disorders. In this study, inspired by the tumor-specific expression of SRY-box transcription factor 4 (Sox4) and matrix metalloproteinase 2 (MMP2), we constructed a doubly regulated plasmid, pGMD, that expresses a biomimetic gasdermin D (GSDMD) protein to induce the caspase-independent pyroptosis of tumor cells. To deliver pGMD to tumor cells, we used a hyaluronic acid (HA)-shelled calcium carbonate nanoplatform, H-CNP@pGMD, which effectively degrades in the acidic endosomal environment, releasing pGMD into the cytoplasm of tumor cells. Upon the initiation of Sox4, biomimetic GSDMD was expressed and cleaved by MMP2 to induce tumor-cell-specific pyroptosis. H-CNP@pGMD effectively inhibited tumor growth and induced strong immune memory effects, preventing tumor recurrence. We demonstrate that H-CNP@pGMD-induced biomimetic GSDMD expression and tumor-specific pyroptosis provide a novel approach to boost cancer immunotherapy.


Assuntos
Neoplasias , Piroptose , Humanos , Metaloproteinase 2 da Matriz/metabolismo , Gasderminas , Biomimética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas de Neoplasias/farmacologia , Caspases/metabolismo , Caspases/farmacologia , Neoplasias/terapia
14.
Reprod Toxicol ; 124: 108544, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38246475

RESUMO

The combined effects of air pollution and extreme temperature on PTB remain unclear. To evaluate the independent effect and interaction effect of prenatal extreme exposure to air quality index (AQI) and Humidex, on PTB. Based on the National Health Care Data Platform of Shandong University, women who gave birth in 2019-2020 were selected for the study. First, the independent effects of AQI and Humidex on PTB were assessed by logistic regression model. Subsequently, the interaction effects of AQI and Humidex on PTB were estimated separately by calculation of the relative excess risk of interaction (RERI). A total of 34365 pregnant women were included and 1975 subjects were diagnosed with PTB. We observed a significant increase in the odds of PTB associated with maternal high AQI exposure, with an OR of 1.70 (95% CI: 1.59, 1.81). Similarly, extreme exposure to Humidex also demonstrated an elevated PTB odds, with a low Humidex OR of 2.48 (95% CI: 2.23, 2.76) and a high Humidex OR of 1.48 (95% CI: 1.31, 1.67). Finally, we observed an interaction between high AQI and extreme Humidex during the 1st trimester. Interaction effects were noted between high AQI and low Humidex throughout the entire trimester and the 2nd trimester. This study suggests that prenatal exposure to high AQI and extreme Humidex could increase the odds of PTB, with effects exhibiting the sensitivity window and a cumulative trend. Additionally, there is an interaction between AQI and Humidex.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Nascimento Prematuro , Efeitos Tardios da Exposição Pré-Natal , Humanos , Feminino , Recém-Nascido , Gravidez , Nascimento Prematuro/epidemiologia , Poluentes Atmosféricos/análise , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Exposição Materna/efeitos adversos , China/epidemiologia , Material Particulado/análise
15.
Nano Lett ; 24(5): 1620-1628, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38277130

RESUMO

Neuromorphic devices have attracted significant attention as potential building blocks for the next generation of computing technologies owing to their ability to emulate the functionalities of biological nervous systems. The essential components in artificial neural networks such as synapses and neurons are predominantly implemented by dedicated devices with specific functionalities. In this work, we present a gate-controlled transition of neuromorphic functions between artificial neurons and synapses in monolayer graphene transistors that can be employed as memtransistors or synaptic transistors as required. By harnessing the reliability of reversible electrochemical reactions between carbon atoms and hydrogen ions, we can effectively manipulate the electric conductivity of graphene transistors, resulting in a high on/off resistance ratio, a well-defined set/reset voltage, and a prolonged retention time. Overall, the on-demand switching of neuromorphic functions in a single graphene transistor provides a promising opportunity for developing adaptive neural networks for the upcoming era of artificial intelligence and machine learning.

16.
Bioresour Technol ; 394: 130285, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38184087

RESUMO

The aim of this study was to reveal the mechanism by which co-inoculation with both Trichoderma viridis and Bacillus subtilis improved the efficiency of composting and degradation of lignocellulose in agricultural waste. The results showed that co-inoculation with Trichoderma and Bacillus increased abundance of Bacteroidota to promote the maturation 7 days in advance. Galbibacter may be a potential marker of co-inoculation composting efficiency compost. The compost became dark brown, odorless, and had a carbon to nitrogen ratio of 16.40 and a pH of 8.2. Moreover, Actinobacteriota and Firmicutes still dominated the degradation of lignocellulose following inoculation with Trichoderma or Bacillus 35 days after composting. Bacterial function prediction analysis showed that carbohydrate metabolism was the primary metabolic pathway. In conclusion, co-inoculation with Trichoderma and Bacillus shortened the composting cycle and accelerated the degradation of lignocellulose. These findings provide new strategies for the efficient use of agricultural waste to produce organic fertilizers.


Assuntos
Bacillus , Compostagem , Lignina , Trichoderma , Bacillus subtilis , Solo , Esterco
17.
IEEE Trans Med Imaging ; 43(2): 638-648, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37703138

RESUMO

We introduce an ultrasound speckle decorrelation-based time-lagged functional ultrasound technique (tl-fUS) for the quantification of the relative changes in cerebral blood flow speed (rCBF [Formula: see text]), cerebral blood volume (rCBV) and cerebral blood flow (rCBF) during functional stimulations. Numerical simulations, phantom validations, and in vivo mouse brain experiments were performed to test the capability of tl-fUS to parse out and quantify the ratio change of these hemodynamic parameters. The blood volume change was found to be more prominent in arterioles compared to venules and the peak blood flow changes were around 2.5 times the peak blood volume change during brain activation, agreeing with previous observations in the literature. The tl-fUS shows the ability of distinguishing the relative changes of rCBFspeed, rCBV, and rCBF, which can inform specific physiological interpretations of the fUS measurements.


Assuntos
Neoplasias Encefálicas , Hemodinâmica , Animais , Camundongos , Volume Sanguíneo , Ultrassonografia , Encéfalo/diagnóstico por imagem , Circulação Cerebrovascular , Imageamento por Ressonância Magnética/métodos
18.
Bioresour Technol ; 393: 130137, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38040311

RESUMO

Starvation disturbance due to nutrient limitation is a common problem in bioreactors. However, an understanding of how microbial systems respond to starvation remains in its infancy. Here the metabolic response mechanism of a biofilm community to starvation was investigated using a well-controlled gaseous toluene treatment biofilter through interruption of its operation. It was found that metabolic characteristics showed significant differences before and after starvation. The dominant carbon source utilization type shifted from amino acids and carboxylic acids to esters and carbohydrates after starvation, which is more conducive to improving energy production. Metagenomic sequencing analysis supported that the changes in the dominant metabolic substrate, enhanced metabolic stability, and flexibility in the mode of energy metabolism could be the main ways to guarantee functional resilience in ecosystems after starvation. The results highlight the microbial metabolic response to starvation, which would be beneficial to the understanding of functional resilience and bioreactor stability.


Assuntos
Ecossistema , Resiliência Psicológica , Gases , Metagenoma , Carbono , Reatores Biológicos
19.
Opt Express ; 31(23): 37365-37380, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-38017867

RESUMO

Accurate estimation of the diffuse attenuation coefficient of photosynthetically active radiation, Kd(PAR), is critical for understanding and modeling key physical, chemical, and biological processes in waters. In this study, a deep learning model (DLKPAR) was developed for remotely estimating Kd(PAR). Compared to the traditional empirical algorithms and semi-analytical algorithm, DLKPAR demonstrated an improvement in the model's stability and accuracy. By using in situ NOMAD data to evaluate the model's performance, DLKPAR had lower root mean square difference (RMSD; 0.028 vs. 0.030-0.048 m-1) and mean absolute relative difference (MARD; 0.14 vs. 0.17-0.25) and higher R2 (0.94 vs. 0.82-0.94). The statistical results of the matchup NOMAD and Argo data to the MODIS also indicated DLKPAR improves the inversion accuracy of Kd(PAR) and could be applied to remotely estimate Kd(PAR) in the global oceans. Therefore, we anticipate that DLKPAR could yield reliable Kd(PAR) values from ocean color remote sensing, providing an accurate estimation of visible light attenuation in the upper ocean and facilitating biogeochemical cycle research.

20.
Open Med (Wars) ; 18(1): 20230837, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38025529

RESUMO

Our objective was to evaluate the long-term prognostic value of high-sensitivity cardiac troponin-I (hs-cTn-I) in idiopathic dilated cardiomyopathy (DCM). First, patients were divided into an end-event group (n = 55) and a non-end-event group (n = 67). Then, patients were included in the subgroup analysis to compare the diagnostic value of brain natriuretic peptide (BNP) and hs-cTn-I in different populations. hs-cTn-I and BNP concentrations were higher in the end-event group. The Cox regression analysis indicated that high hs-cTn-I was a risk factor for poor long-term prognosis. Receiver operating characteristic analysis showed that the area under the curve (AUC) for hs-cTn-I to predict end events was 0.751, and the AUC for BNP was 0.742. The correlation analysis suggested that hs-cTn-I was related to the percentage change in left ventricular internal diameter at end-diastolic and left ventricular ejection fraction. Subgroup analysis showed that compared with BNP, hs-cTn-I was more suitable for predicting end events in patients with preserved renal function (AUC: 0.853 vs 0.712, P = 0.04). In conclusion, hs-cTn-I is a potential biomarker for evaluating long-term prognosis in idiopathic DCM, and its predictive value is higher than that of BNP in patients with preserved renal function.

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