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1.
Nano Lett ; 2022 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-35507685

RESUMO

Circularly polarized light (CPL) is essential for optoelectronic and chiro-spintronic applications. Hybrid perovskites, as star optoelectronic materials, have demonstrated CPL activity, which is, however, mostly limited to chiral perovskites. Here, we develop a simple, general, and efficient strategy to stimulate CPL activity in achiral perovskites, which possess rich species, efficient luminescence, and tunable bandgaps. With the formation of van der Waals heterojunctions between chiral and achiral perovskites, a nonequilibrium spin population and thus CPL activity are realized in achiral perovskites by receiving spin-polarized electrons from chiral perovskites. The polarization degree of room-temperature CPL in achiral perovskites is at least one order of magnitude higher than in chiral ones. The CPL polarization degree and emission wavelengths of achiral perovskites can be flexibly designed by tuning chemical compositions, operating temperature, or excitation wavelengths. We anticipate that unlimited types of achiral perovskites can be endowed with CPL activity, benefiting their applications in integrated CPL sources and detectors.

2.
Signal Transduct Target Ther ; 7(1): 156, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35538061

RESUMO

Artificial intelligence is an advanced method to identify novel anticancer targets and discover novel drugs from biology networks because the networks can effectively preserve and quantify the interaction between components of cell systems underlying human diseases such as cancer. Here, we review and discuss how to employ artificial intelligence approaches to identify novel anticancer targets and discover drugs. First, we describe the scope of artificial intelligence biology analysis for novel anticancer target investigations. Second, we review and discuss the basic principles and theory of commonly used network-based and machine learning-based artificial intelligence algorithms. Finally, we showcase the applications of artificial intelligence approaches in cancer target identification and drug discovery. Taken together, the artificial intelligence models have provided us with a quantitative framework to study the relationship between network characteristics and cancer, thereby leading to the identification of potential anticancer targets and the discovery of novel drug candidates.


Assuntos
Inteligência Artificial , Neoplasias , Algoritmos , Descoberta de Drogas , Humanos , Aprendizado de Máquina , Neoplasias/tratamento farmacológico , Neoplasias/genética
3.
Brief Bioinform ; 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35514182

RESUMO

The development of single-cell RNA-sequencing (scRNA-seq) technologies has offered insights into complex biological systems at the single-cell resolution. In particular, these techniques facilitate the identifications of genes showing cell-type-specific differential expressions (DE). In this paper, we introduce MARBLES, a novel statistical model for cross-condition DE gene detection from scRNA-seq data. MARBLES employs a Markov Random Field model to borrow information across similar cell types and utilizes cell-type-specific pseudobulk count to account for sample-level variability. Our simulation results showed that MARBLES is more powerful than existing methods to detect DE genes with an appropriate control of false positive rate. Applications of MARBLES to real data identified novel disease-related DE genes and biological pathways from both a single-cell lipopolysaccharide mouse dataset with 24 381 cells and 11 076 genes and a Parkinson's disease human data set with 76 212 cells and 15 891 genes. Overall, MARBLES is a powerful tool to identify cell-type-specific DE genes across conditions from scRNA-seq data.

4.
J Clin Invest ; 132(9)2022 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-35499080

RESUMO

Activated SUMOylation is a hallmark of cancer. Starting from a targeted screening for SUMO-regulated immune evasion mechanisms, we identified an evolutionarily conserved function of activated SUMOylation, which attenuated the immunogenicity of tumor cells. Activated SUMOylation allowed cancer cells to evade CD8+ T cell-mediated immunosurveillance by suppressing the MHC class I (MHC-I) antigen-processing and presentation machinery (APM). Loss of the MHC-I APM is a frequent cause of resistance to cancer immunotherapies, and the pharmacological inhibition of SUMOylation (SUMOi) resulted in reduced activity of the transcriptional repressor scaffold attachment factor B (SAFB) and induction of the MHC-I APM. Consequently, SUMOi enhanced the presentation of antigens and the susceptibility of tumor cells to CD8+ T cell-mediated killing. Importantly, SUMOi also triggered the activation of CD8+ T cells and thereby drove a feed-forward loop amplifying the specific antitumor immune response. In summary, we showed that activated SUMOylation allowed tumor cells to evade antitumor immunosurveillance, and we have expanded the understanding of SUMOi as a rational therapeutic strategy for enhancing the efficacy of cancer immunotherapies.


Assuntos
Apresentação do Antígeno , Neoplasias , Antígenos de Histocompatibilidade Classe I , Humanos , Evasão da Resposta Imune , Neoplasias/patologia , Sumoilação
5.
Artigo em Inglês | MEDLINE | ID: mdl-35507915

RESUMO

ABSTRACT: Levosimendan and milrinone are two effective inotropic drugs to maintain cardiac output in acute heart failure (AHF). Using data from AHF patients with and without abnormal renal function, we performed this single-center, retrospective cohort study to compare the effectiveness and safety of milrinone and levosimendan for the initial management of AHF. Patients admitted for heart failure between December 2016 and September 2019 who received levosimendan or milrinone as initial inotrope therapy in the cardiology department were identified. A total of 436 levosimendan and 417 milrinone patients with creatinine clearance (CrCl) ≥30 ml/min and 50 levosimendan and 71 milrinone patients with CrCl <30 ml/min or on dialysis were included. The primary outcome was a composite of changes in clinical status at 15 and 30 days following initial inotrope therapy discontinuation. Between subgroups of patients with CrCl ≥30 ml/min, there were no significant differences in primary outcomes; milrinone was associated with more frequent hypotension and cardiac arrhythmias during the infusion period (p<0.01), while levosimendan was associated with more frequent cardiac arrhythmias within 48 h after discontinuation (p<0.05). Of the patients with CrCl <30 ml/min or on dialysis, more initial levosimendan than milrinone patients and that switched alternative inotropes experienced clinical worsening at 15 days and 30 days (p<0.05). According to our results, AHF patients with severe renal dysfunction should avoid initial inotrope therapy with levosimendan.

6.
Stem Cells ; 40(1): 59-73, 2022 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-35511865

RESUMO

Increased neurogenesis elicits antidepressive-like effects. The antidiabetic drug metformin (Met) reportedly promotes hippocampal neurogenesis, which ameliorates spatial memory deficits and depression-like behaviors. However, the precise molecular mechanisms underpinning Met-induced neuronal differentiation of neural stem cells (NSCs) remain unclear. We showed that Met enhanced neuronal differentiation of NSCs via Gadd45g but not Gadd45a and Gadd45b. We further found that Gadd45g increased demethylation of neurogenic differentiation 1 promoter by regulating the activity of passive and active DNA demethylation enzymes through an adenylate-activated protein kinase -independent mechanism in Met-treated NSCs. Importantly, genetic deficiency of Gadd45g decreased hippocampal neurogenesis, which could contribute to spatial memory decline, and depression-like behaviors in the adult mice, whereas forced expression of Gadd45g alleviated the depressive-like behaviors. Our findings provide a model that Gadd45g-mediated DNA demethylation contributes to Met-induced neuronal genesis and its antidepressant-like effects and propose the concept that targeting Gadd45g regulation of neurogenesis might serve as a novel antidepressant strategy.


Assuntos
Metformina , Células-Tronco Neurais , Animais , Antidepressivos/metabolismo , Antidepressivos/farmacologia , Antígenos de Diferenciação/genética , Antígenos de Diferenciação/metabolismo , Desmetilação do DNA , Hipocampo/metabolismo , Metformina/metabolismo , Metformina/farmacologia , Camundongos , Células-Tronco Neurais/metabolismo , Neurogênese
7.
Cell Death Dis ; 13(5): 449, 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35562171

RESUMO

Energy restriction (ER) protects against cerebral ischemic injury, but the underlying mechanism remains largely unclear. Here, rats were fed ad libitum (AL) or on an alternate-day food deprivation intermittent fasting (IF) diet for 3 months, followed by middle cerebral artery occlusion (MCAO) surgery. The body weight, infarct volume, and neurological deficit score were accessed at the designated time points. ELISA, qRT-PCR, and Western blotting were used to determine cytokine secretion and the expression of SIRT6, TXNIP, and signaling molecules, respectively. Immunofluorescence evaluated microglial activation and angiogenesis in vivo. For in vitro study, oxygen-glucose deprivation/reoxygenation (OGD/R)-treated cell model was generated. MTT and tube formation assays were employed to determine cell viability and tube formation capability. ChIP assay detected chromatin occupancy of SIRT6 and SIRT6-mediated H3 deacetylation. We found that IF or ER mimetics ameliorated cerebral ischemic brain damage and microglial activation, and potentiated angiogenesis in vivo. ER mimetics or SIRT6 overexpression alleviated cerebral ischemia and reperfusion (I/R)-induced injury in vitro. SIRT6 suppressed TXNIP via deacetylation of H3K9ac and H3K56ac in HAPI cells and BMVECs. Downregulation of SIRT6 reversed ER mimetics-mediated protection during cerebral I/R in vitro. Our study demonstrated that ER-mediated upregulation of SIRT6 inhibited microglia activation and potentiated angiogenesis in cerebral ischemia via suppressing TXNIP.

8.
Acta Pharm Sin B ; 12(3): 1240-1253, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35530150

RESUMO

The mammalian target of rapamycin (mTOR) pathway is abnormally activated in lung cancer. However, the anti-lung cancer effect of mTOR inhibitors as monotherapy is modest. Here, we identified that ginsenoside Rh2, an active component of Panax ginseng C. A. Mey., enhanced the anti-cancer effect of the mTOR inhibitor everolimus both in vitro and in vivo. Moreover, ginsenoside Rh2 alleviated the hepatic fat accumulation caused by everolimus in xenograft nude mice models. The combination of everolimus and ginsenoside Rh2 (labeled Eve-Rh2) induced caspase-independent cell death and cytoplasmic vacuolation in lung cancer cells, indicating that Eve-Rh2 prevented tumor progression by triggering paraptosis. Eve-Rh2 up-regulated the expression of c-MYC in cancer cells as well as tumor tissues. The increased c-MYC mediated the accumulation of tribbles homolog 3 (TRIB3)/P62+ aggresomes and consequently triggered paraptosis, bypassing the classical c-MYC/MAX pathway. Our study offers a potential effective and safe strategy for the treatment of lung cancer. Moreover, we have identified a new mechanism of TRIB3/P62+ aggresomes-triggered paraptosis and revealed a unique function of c-MYC.

9.
Artigo em Inglês | MEDLINE | ID: mdl-35533163

RESUMO

Background clutters pose challenges to defocus blur detection. Existing approaches often produce artifact predictions in background areas with clutter and relatively low confident predictions in boundary areas. In this work, we tackle the above issues from two perspectives. Firstly, inspired by the recent success of self-attention mechanism, we introduce channel-wise and spatial-wise attention modules to attentively aggregate features at different channels and spatial locations to obtain more discriminative features. Secondly, we propose a generative adversarial training strategy to suppress spurious and low reliable predictions. This is achieved by utilizing a discriminator to identify predicted defocus map from ground-truth ones. As such, the defocus network (generator) needs to produce 'realistic' defocus map to minimize discriminator loss. We further demonstrate that the generative adversarial training allows exploiting additional unlabeled data to improve performance, a.k.a. semi-supervised learning, and we provide the first benchmark on semi-supervised defocus detection. Finally, we demonstrate that the existing evaluation metrics for defocus detection generally fail to quantify the robustness with respect to thresholding. For a fair and practical evaluation, we introduce an effective yet efficient AUFß metric. Extensive experiments on three public datasets verify the superiority of the proposed methods compared against state-of-the-art approaches.

10.
Zhongguo Zhong Yao Za Zhi ; 47(8): 2056-2063, 2022 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-35531721

RESUMO

A chronic cholestasis model was induced in mice by feeding a diet containing 3,5-diethoxycarbonyl-1,4-dihydro-2,4,6-trimethylpyridine(DDC). The effects of Ershiwuwei Songshi Pills(ESP) on endogenous metabolites in mice with chronic cholestasis were investigated by metabolomics analysis based on liquid chromatography-mass spectrometry(LC-MS). The results showed that ESP was effective in improving pathological injury and reducing serum levels of alanine aminotransferase(ALT), aspartate aminotransferase(AST), alkaline phosphatase(ALP), and total bile acid in the model mice. Meanwhile, 13 common differential metabolites were revealed in metabolomic screening between the model/control group and the model/ESP group, including uric acid, glycolaldehyde, kynurenine, flavin adenine dinucleotide, L-3-phenyllactic acid, I-urobilin, leukotriene D4(LTD4), taurocholic acid, trioxilin A3, D-inositol-1,4-diphosphate, PC [16:0/20:2(11Z,14Z)], PC[14:0/22:2(13Z,16Z)], and PC[20:4(5Z,8Z,11Z,14Z)/20:4(5Z,8Z,11Z,14Z)]. After ESP intervention, the levels of all 13 differential metabolites were significantly retraced, and pathway analysis showed that ESP achieved its therapeutic effect mainly by affecting arachidonic acid metabolism, glycerophospholipid metabolism, tryptophan metabolism, and primary bile acid biosynthesis. This study elucidated the mechanism of action of ESP against chronic cholestasis based on metabolites.


Assuntos
Colestase , Medicina Tradicional Tibetana , Animais , Ácidos e Sais Biliares , Colestase/tratamento farmacológico , Cromatografia Líquida , Metabolômica , Camundongos
11.
Opt Lett ; 47(10): 2446-2449, 2022 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-35561372

RESUMO

Terahertz (THz) absorption spectroscopy is a powerful tool for molecular label-free fingerprinting, but it faces a formidable hurdle in enhancing the broadband spectral signals in trace-amount analysis. In this paper, we propose a sensing method based on the geometry scanning of metal metasurfaces with spoof surface polarization sharp resonances by numerical simulation. This scheme shows a significant absorption enhancement factor of about 200 times in an ultra-wide terahertz band to enable the explicit identification of various analytes, such as a trace-amount thin lactose film samples. The proposed method provides a new, to the best of our knowledge, choice for the enhancement of wide terahertz absorption spectra, and paves the way for the detection of trace-amount chemical, organic, or biomedical materials in the terahertz regime.

12.
Cell Oncol (Dordr) ; 2022 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-35579750

RESUMO

PURPOSE: N6-methyladenosine (m6A), the most prevalent mRNA modification, plays an essential role in tumorigenesis. Notably, increasing interest has been directed to bioactive peptides (BPs) with antitumor activities. Here, we set out to investigate the potential of the BP-regulated ALKBH5/MLST8/EIF4EBP1 axis on prevention and treatment of acute myeloid leukemia (AML). METHODS: The biological effects of BP on AML cells were detected by MTT and ApoLive-Glo™ multiplex assays. The role of BP in tumor growth was determined by a subcutaneous xenograft model. The ALKBH5/MLST8/EIF4EBP1 axis was identified as a potential BP target in AML via methylated RNA immunoprecipitation sequencing (MeRIP-seq) combined with RNA sequencing (RNA-seq). Western blot, RT-qPCR, MeRIP-qPCR, dual-luciferase reporter and RNA stability assays were performed to validate the function and mode of action of the BP-regulated ALKBH5/MLST8/EIF4EBP1 axis. The clinical relevance of the BP-regulated ALKBH5/MLST8/EIF4EBP1 axis in AML was confirmed by TCGA data analysis. RESULTS: We found that BP can inhibit AML cell proliferation and promote apoptosis in vitro, and repress AML tumor growth in vivo. Mechanistically, we found that BP downregulated ALKBH5 expression, which in turn repressed m6A demethylation of MLST8 and EIF4EBP1 mRNAs. Reduction of the m6A levels of MLST8 and EIF4EBP1 facilitated MLST8 and EIF4EBP1 mRNA decay, resulting in inhibition of AML cell proliferation. Furthermore, we found that the BP-regulated ALKBH5/MLST8/EIF4EBP1 axis closely correlates with AML patient prognosis. CONCLUSIONS: Our data indicate that BP can inhibit acute myeloid leukemia cell proliferation by downregulating ALKBH5-mediated m6A demethylation of EIF4EBP1 and MLST8 mRNAs, which may have potential to prevent and treat this disease.

13.
NanoImpact ; 26: 100403, 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35560288

RESUMO

In this study, we determined the roles of oxidative stress and related signals in mediating transgenerational toxicity of 30 nm polystyrene nanoparticles (PS-NPs) in Caenorhabditis elegans. Using brood size and locomotion behavior as endpoints, exposure to 1-100 µg/L PS-NPs caused transgenerational toxicity. Meanwhile, the activation of reactive oxygen species (ROS) was also observed transgenerationally after exposure to 1-100 µg/L PS-NPs. After exposure to 1 µg/L PS-NPs, the transgenerational toxicity was monitored until F2 generation (F2-G) and recovered at F3-G. At the F1-G of 1 µg/L PS-NPs-exposed nematodes, RNAi knockdown of daf-2 with function to inhibit oxidative stress suppressed the transgenerational toxicity and increased the mitochondrial SOD-3 expression. In contrast, at F3-G of 1 µg/L PS-NPs-exposed nematodes, RNAi knockdown of mev-1 with function to induce oxidative stress promoted locomotion and brood size, and suppressed the SOD-3 expression. Moreover, we observed the dynamic expressions of mev-1, daf-2, and sod-2 transgenerationally after exposure to 1 µg/L PS-NPs at P0-G, which further suggested the involvement of MEV-1, DAF-2, and SOD-3 in affecting induction of transgenerational PS-NP toxicity. Therefore, we provided the evidence to suggest the roles of oxidative stress activation and related molecular signals in mediating induction of transgenerational PS-NP toxicity. Our data highlights the crucial function of oxidative stress-related signals during induction of transgenerational PS-NP toxicity.

14.
J Hazard Mater ; 434: 128922, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35452991

RESUMO

The acesulfame (ACE) degradation in waste activated sludge (WAS) via direct anaerobic fermentation is difficult and the efficient elimination techniques are imperative for the ultimate safe WAS disposal. Persulfate (PS)-based approach was developed to promote the ACE removal during WAS anaerobic fermentation. Results demonstrated the effectiveness of PS-based treatments on ACE degradation, and the ACE removal efficiency was respectively 48.2% and 96.2% in the PS and PS/Fe-treated reactors while it was only 6.0% in the control reactor. Mechanism explorations revealed that the active free radicals (i.e. OH• and SO4•-) generated in the PS-based reactors were the key oxidative species for the ACE degradation. However, such effects were interfered by the released soluble substrates (i.e. protein, carbohydrate and inorganic ions) during anaerobic fermentation by competing and/or quenching free radicals, which caused the deceleration of the ACE removal efficiency. Moreover, the PS-based treatment facilitated the enrichment of functional microorganisms (i.e. Phyllobacteriaceae and Bradyrhizobiaceae) and upregulated the critical genes (i.e. pncB and nadE) involved in the ACE degradation. Based on the density functional theory (DFT) and metabolic intermediates analysis, the hydroxylation and oxidative ring-opening were the two main proposed metabolic pathways for ACE degradation. Overall, the combined chemical and biological metabolism effects collectively contributed to the efficient ACE degradation, and it provided a novel and effective strategy for refractory pollutants removal during WAS anaerobic fermentation.

15.
Drug Deliv ; 29(1): 1184-1200, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35403517

RESUMO

Self-assembling peptides (SAPs) have enormous potential in medical and biological applications, particularly noninvasive tumor therapy. SAPs self-assembly is governed by multiple non-covalent interactions and results in the formation of a variety of morphological features. SAPs can be assembled in a variety of ways, including chemical conjugation and physical encapsulation, to incorporate multiple bioactive motifs. Peptide-based nanomaterials are used for chemotherapy, delivery vehicles, immunotherapy, and noninvasive tumor therapies (e.g. photodynamic therapy) by employing the self-assembling properties of peptides. The recent increase of SAPs is almost entirely due to their excellent biocompatibility, responsiveness toward tumor microenvironment, multivalency, and structural versatility. Synergistic therapy is a more effective and powerful approach to treat the tumor. Notably, SAPs can be used to subtly combine various treatments. Importantly, SAPs are capable of subtly making the combination of various treatments. This review describes mechanisms of peptides self-assemble into various structures and their biomedical applications with a focus on possible treatments.


Assuntos
Nanoestruturas , Neoplasias , Humanos , Hidrogéis/química , Fatores Imunológicos , Imunoterapia , Nanoestruturas/química , Neoplasias/tratamento farmacológico , Peptídeos/química , Microambiente Tumoral
16.
Artigo em Inglês | MEDLINE | ID: mdl-35457320

RESUMO

This paper explores the spatial relationship between urbanization and urban household carbon emissions at the prefectural level and above cities in China and uses Exploratory Spatial Data Analysis (ESDA) and Geographically Weighted Regression (GWR) to reveal the extent of the impact of urbanization on urban household carbon emissions and the spatial and temporal variation characteristics. The results show that: Overall carbon emissions of urban households in cities of China showed a decreasing trend during the study period, but there were significant differences in the carbon emissions of urban households in the four major regions. In terms of the spatial and temporal characteristics of urban household carbon emissions, the urban "head effect" of urban household carbon emissions is obvious. The high-high clustering of urban household carbon emissions is characterized by a huge triangular spatial distribution of "Beijing-Tianjin-Hebei, Chengdu-Chongqing, and Shanghai". The level of urbanization in Chinese cities at the prefecture level and above shows a spatial pattern of decreasing levels of urbanization in the east, middle, and west. The four subsystems of urbanization are positively correlated with urban household carbon emissions in the same direction. The urbanization factors have a contributory effect on some cities' carbon emissions of urban households, but there are significant regional differences in the impact of urbanization factors on urban household carbon emissions in the eastern, central, and western regions of China, as they are at different stages of rapid urbanization development.


Assuntos
Carbono , Urbanização , Pequim , Carbono/análise , China , Cidades
17.
Nutrients ; 14(8)2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35458183

RESUMO

Gestational hypertension may interfere with the placental iron metabolism, thus probably increasing the risk of childhood anemia. We aim to examine the association between gestational hypertension and childhood anemia at different ages in two large Chinese birth cohorts. Cohort 1 was conducted in 5 counties in northern China and was comprised of 17,264 mother-children pairs (97.3%) during 2006-2009, whereas cohort 2 was conducted in 21 counties in southern China and was comprised of 185,093 mother-children pairs (93.8%) during 1993-1996. All pregnant women were registered in a monitoring system and followed up until the termination of pregnancies. The childhood anemia was diagnosed at 6 month and 12 month in cohort 1 and at 55 month in cohort 2. The overall incidence of childhood anemia was 6.78% and 5.28% at 6 month and 12 month, respectively, in cohort 1 and 13.18% at 55 month in cohort 2. Gestational hypertension was associated with increased risk of anemia at 6 month (adjusted Odds Ratio (OR): 1.31; 95% confidence interval (CI): 1.05, 1.63) and at 12 month (adjusted OR: 1.50; 95% CI: 1.18, 1.90) in cohort 1 and at 55 month (adjusted OR: 1.06; 95% CI: 1.01, 1.12) in cohort 2. The hemoglobin values of children at different ages were lower among gestational hypertension group in the linear models, which was consistent with the results of binary regression analysis. Our study found gestational hypertension may associate with an increased risk of childhood anemia. It suggests a possible need for exploring changes in prenatal care that might prevent childhood anemia.


Assuntos
Anemia , Hipertensão Induzida pela Gravidez , Anemia/epidemiologia , Pré-Escolar , China/epidemiologia , Feminino , Humanos , Hipertensão Induzida pela Gravidez/epidemiologia , Placenta , Gravidez , Fatores de Risco
18.
Bioresour Technol ; 352: 127102, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35367604

RESUMO

Nano-biochar application was investigated for anaerobic digestion of orange peel waste. The application for methane production focused on the optimization of biochar feedstock, rescue of failed digesters, and microbial succession analysis. It showed that sewage sludge (SS) derived biochar had the highest performance enhancement among the different feedstocks, which could be ascribed to the improvement of electron transfer, interspecies hydrogen transfer, and supply of trace elements. Subsequently, nano SS biochar-amended digestate was evaluated for rescuing failed digesters, and the experimental results indicated its positive roles through gradual bioaugmentation operation. The dynamic analysis of microbial succession indicated the successful application was through the mechanism of restoring partially the functional microbial communities. The major reconstruction of functional microorganisms included bacteria phyla Hydrogenispora (24.5%) and Defluviitoga (18.8%) as well as methanogenic genera of Methanosarcina (41.5%) and Methanobacterium (27.3%). These findings would contribute to rescuing failed anaerobic digesters by bioaugmentation with biochar-amended digestate.


Assuntos
Reatores Biológicos , Metano , Anaerobiose , Carvão Vegetal , Esgotos
19.
Sci Total Environ ; 832: 155017, 2022 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-35395305

RESUMO

Venlafaxine and citalopram have been commonly found in surface water and may disrupt fish reproduction, yet the long-term impact and the underlying mechanism are largely unknown. Here, zebrafish were exposed to 0.1-100 µg/L venlafaxine and citalopram for their entire life cycle from embryo to adult, respectively. After exposure for 180 days, the lowest observable effective concentration (LOEC) of venlafaxine and citalopram to significantly reduce the mean number of egg production in adults were 10 and 1 µg/L, respectively, whereas the fertilization rate displayed no significant changes. Further, we investigated the impacts of venlafaxine and citalopram in a reproductive context, including sperm quality and reproductive behaviour. In contrast, venlafaxine and citalopram exposure did not affect sperm quality but caused a reduction of reproductive behaviour (e.g., mating duration and mating interval) of adults exposed to 1-10 µg/L of the antidepressant. Transcriptomic profiling of the whole ovary revealed that lifecycle venlafaxine and citalopram exposure significantly affected the Na+/Cl- dependent neurotransmitter transporters signaling. Moreover, immune system-mediated ovarian regeneration and creatine metabolism regulated energy metabolism were proposed as the novel mechanism in the observed effects. Taken together, our results highlight the risk of lifecycle venlafaxine and citalopram exposure to fish reproduction and provide novel perspectives for unveiling the mechanism of female reproductive dysfunction.

20.
IEEE Trans Image Process ; 31: 3125-3136, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35412981

RESUMO

Recent progress on salient object detection (SOD) mainly benefits from multi-scale learning, where the high-level and low-level features collaborate in locating salient objects and discovering fine details, respectively. However, most efforts are devoted to low-level feature learning by fusing multi-scale features or enhancing boundary representations. High-level features, which although have long proven effective for many other tasks, yet have been barely studied for SOD. In this paper, we tap into this gap and show that enhancing high-level features is essential for SOD as well. To this end, we introduce an Extremely-Downsampled Network (EDN), which employs an extreme downsampling technique to effectively learn a global view of the whole image, leading to accurate salient object localization. To accomplish better multi-level feature fusion, we construct the Scale-Correlated Pyramid Convolution (SCPC) to build an elegant decoder for recovering object details from the above extreme downsampling. Extensive experiments demonstrate that EDN achieves state-of-the-art performance with real-time speed. Our efficient EDN-Lite also achieves competitive performance with a speed of 316fps. Hence, this work is expected to spark some new thinking in SOD. Code is available at https://github.com/yuhuan-wu/EDN.

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