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In this paper, four heteroleptic Ce(III) complexes, including Ce(thd)3-phen (thd = 2,2,6,6-tetramethyl-3,5-heptanedione, phen = 1, 10-phenanthroline (1), Ce(thd)3-MEDA (MEDA = N-Methylethylenediamine (2), Ce(thd)3-MOMA (MOMA = N-(2-Methoxyethyl)methylamine (3), and Ce(thd)3-DMDE (DMDE = N,Nâ³-dimethyl ethanol amine (4), were synthesized and characterized with 1H-NMR, elemental analysis, and X-ray single-crystal diffraction. The thermogravimetric analysis and vapor pressure results indicated that the complexing ability of a nitrogen-containing bidentate ligand with a cerium ion was stronger than that of a mixed oxygen-nitrogen-containing bidentate ligand. Complex 2 was selected as an ALD precursor to deposit a CeO2 film on a SiO2/Si (100) wafer. The self-limited deposition results demonstrated that complex 2 was a potential ALD precursor.
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CD4+ T cells are central mediators of protective immunity to blood-stage malaria, particularly for their capacity in orchestrating germinal center reaction and generating parasite-specific high-affinity antibodies. T follicular helper (Tfh) cells are predominant CD4+ effector T cell subset implicated in these processes, yet the factors and detailed mechanisms that assist Tfh cell development and function during Plasmodium infection are largely undefined. Here we provide evidence that receptor for activated C kinase 1 (RACK1), an adaptor protein of various intracellular signals, is not only important for CD4+ T cell expansion as previously implied but also plays a prominent role in Tfh cell differentiation and function during blood-stage Plasmodium yoelii 17XNL infection. Consequently, RACK1 in CD4+ T cells contributes significantly to germinal center formation, parasite-specific IgG production, and host resistance to the infection. Mechanistic exploration detects specific interaction of RACK1 with STAT3 in P. yoelii 17XNL-responsive CD4+ T cells, ablation of RACK1 leads to defective STAT3 phosphorylation, accompanied by substantially lower amount of STAT3 protein in CD4+ T cells, whereas retroviral overexpression of RACK1 or STAT3 in RACK1-deficient CD4+ T cells greatly restores STAT3 activity and Bcl-6 expression under the Tfh polarization condition. Further analyses suggest RACK1 positively regulates STAT3 stability by inhibiting the ubiquitin-proteasomal degradation process, thus promoting optimal STAT3 activity and Bcl-6 induction during Tfh cell differentiation. These findings uncover a novel mechanism by which RACK1 participates in posttranslational regulation of STAT3, Tfh cell differentiation, and subsequent development of anti-Plasmodium humoral immunity.
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Diferenciação Celular , Malária , Plasmodium yoelii , Receptores de Quinase C Ativada , Fator de Transcrição STAT3 , Células T Auxiliares Foliculares , Animais , Receptores de Quinase C Ativada/metabolismo , Fator de Transcrição STAT3/metabolismo , Malária/imunologia , Malária/parasitologia , Camundongos , Plasmodium yoelii/imunologia , Células T Auxiliares Foliculares/imunologia , Células T Auxiliares Foliculares/metabolismo , Camundongos Endogâmicos C57BL , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Auxiliares-Indutores/metabolismo , Camundongos Knockout , Centro Germinativo/imunologiaRESUMO
Drawing on a harmonized longitudinal dataset covering more than 55,000 smallholder farms in six African countries, we analyze changes in crop productivity from 2008 to 2019. Because smallholder farmers represent a significant fraction of the world's poorest people, agricultural productivity in this context matters for poverty reduction and for the broader achievement of the UN Sustainable Development Goals. Our analysis measures productivity trends for nationally representative samples of smallholder crop farmers, using detailed data on agricultural inputs and outputs which we integrate with detailed data on local weather and environmental conditions. In spite of government commitments and international efforts to strengthen African agriculture, we find no evidence that smallholder crop productivity improved over this 12-y period. Our preferred statistical specification of total factor productivity (TFP) suggests an overall decline in productivity of -3.5% per year. Various other models we test also find declining productivity in the overall sample, and none of them finds productivity growth. However, the different countries in our sample experienced varying trends, with some instances of growth in some regions. The results suggest that major challenges remain for agricultural development in sub-Saharan Africa. They complement previous analyses that relied primarily on aggregate national statistics to measure agricultural productivity, rather than detailed microdata.
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Agricultura , Produtos Agrícolas , África Subsaariana , Produtos Agrícolas/crescimento & desenvolvimento , Agricultura/métodos , Agricultura/tendências , Humanos , Produção Agrícola/estatística & dados numéricos , Produção Agrícola/tendências , Fazendeiros/estatística & dados numéricos , Fazendas , Desenvolvimento Sustentável/tendênciasRESUMO
Porcine circovirus type 2 (PCV2) is intensely prevalent in global pig farms. The PCV2 vaccine is an important means of preventing and controlling PCV2. The quality control of PCV2 vaccines is predominantly based on detection techniques such as animal testing and neutralizing antibody titration. Measuring the content of effective proteins in vaccines to measure vaccine efficacy is an excellent alternative to traditional methods, which can greatly accelerate the development speed and testing time of vaccines. In this study, we screened a monoclonal antibody (mAb) that can effectively recognize not only the exogenous expression of PCV2 Cap protein but also PCV2 virus. The double antibody sandwich ELISA (DAS-ELISA) was developed using this mAb that specifically recognize PCV2 Cap. The minimum protein content detected by this method is 3.5â¯ng/mL. This method can be used for the quality control of PCV2 inactivated vaccine and subunit vaccine, and the detection results are consistent with the results of mice animal experiments. This method has the advantages of simple operation, good sensitivity, high specificity and wide application. It can detect the effective antigen Cap protein content of various types of PCV2 vaccines, which not only shorten the vaccine inspection time but also save costs.
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Anticorpos Monoclonais , Anticorpos Antivirais , Antígenos Virais , Infecções por Circoviridae , Circovirus , Ensaio de Imunoadsorção Enzimática , Sensibilidade e Especificidade , Doenças dos Suínos , Vacinas Virais , Circovirus/imunologia , Animais , Ensaio de Imunoadsorção Enzimática/métodos , Suínos , Vacinas Virais/imunologia , Anticorpos Monoclonais/imunologia , Antígenos Virais/imunologia , Antígenos Virais/análise , Camundongos , Anticorpos Antivirais/sangue , Infecções por Circoviridae/veterinária , Infecções por Circoviridae/diagnóstico , Infecções por Circoviridae/prevenção & controle , Doenças dos Suínos/diagnóstico , Doenças dos Suínos/prevenção & controle , Doenças dos Suínos/virologia , Proteínas do Capsídeo/imunologiaRESUMO
Transplantation of photoreceptor cells and retinal pigment epithelial (RPE) cells provide a potential therapy for retinal degeneration diseases. Subretinal transplantation of therapeutic donor cells into mouse recipients is challenging due to the limited surgical space allowed by the small volume of the mouse eye. We developed a trans-scleral surgical transplantation platform with direct transpupillary vision guidance to facilitate the subretinal delivery of exogenous cells in mouse recipients. The platform was tested using retinal cell suspensions and three-dimensional retinal sheets collected from rod-rich Rho::EGFP mice and cone-rich OPN1LW-EGFP;NRL-/- mice, respectively. Live/dead assay showed low cell mortality for both forms of donor cells. Retinal grafts were successfully delivered into the subretinal space of a mouse model of retinal degeneration, Rd1/NS, with minimum surgical complications as detected by multimodal confocal scanning laser ophthalmoscope (cSLO) imaging. Two months post-transplantation, histological staining demonstrated evidence of advanced maturation of the retinal grafts into 'adult' rods and cones (by robust Rho::EGFP, S-opsin, and OPN1LW:EGFP expression, respectively) in the subretinal space. Here, we provide a surgical platform that can enable highly accurate subretinal delivery with a low rate of complications in mouse recipients. This technique offers precision and relative ease of skill acquisition. Furthermore, the technique could be used not only for studies of subretinal cell transplantation but also for other intraocular therapeutic studies including gene therapies.
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Degeneração Retiniana , Camundongos , Animais , Degeneração Retiniana/cirurgia , Degeneração Retiniana/metabolismo , Retina/metabolismo , Células Fotorreceptoras Retinianas Cones/metabolismo , Transplante de Células/métodos , Visão OcularRESUMO
Spectral CT can provide material characterization ability to offer more precise material information for diagnosis purposes. However, the material decomposition process generally leads to amplification of noise which significantly limits the utility of the material basis images. To mitigate such problem, an image domain noise suppression method was proposed in this work. The method performs basis transformation of the material basis images based on a singular value decomposition. The noise variances of the original spectral CT images were incorporated in the matrix to be decomposed to ensure that the transformed basis images are statistically uncorrelated. Due to the difference in noise amplitudes in the transformed basis images, a selective filtering method was proposed with the low-noise transformed basis image as guidance. The method was evaluated using both numerical simulation and real clinical dual-energy CT data. Results demonstrated that compared with existing methods, the proposed method performs better in preserving the spatial resolution and the soft tissue contrast while suppressing the image noise. The proposed method is also computationally efficient and can realize real-time noise suppression for clinical spectral CT images.
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Algoritmos , Tomografia Computadorizada por Raios X , Humanos , Tomografia Computadorizada por Raios X/métodos , Processamento de Imagem Assistida por Computador/métodos , Imagens de Fantasmas , Razão Sinal-RuídoRESUMO
Correctly identifying and handling the relationship between land use carbon emission efficiency (LUCEE) and land ecological security (LES) are important to promote carbon neutrality in the overall layout of ecological civilization construction. This study takes 30 provinces in China as the research unit and measures the level of LUCEE and LES in each province in the period from 2011 to 2020 via a super-efficient slack-based measure model considering undesirable output. The coupling coordination degree (CCD) of LUCEE and LES is calculated, and its spatiotemporal evolution pattern is explored by kernel density estimation and standard deviational ellipse (SDE). The Dagum Gini coefficient is used to study spatial regional differences and the sources of differences. Results show that (1) China's LUCEE exhibited a downward and then an upward trend, as well as a spatial pattern of "high in the west and low in the east" with obvious regional differences. The LES experienced a positive transformation of "less secure â basically secure â more secure" nationwide, with no apparent regional differences. (2) The kernel density curves showed a continuous increase in CCD in general, while interprovincial differences increased, then decreased, and shifted from multipolar to bipolar differentiation. (3) The migration of SDE centers in CCD demonstrated a path of "southeast â southwest â northeast," and the ellipticity increased from 0.167 to 0.173, showing a trend of concentrated distribution. (4) The overall Gini coefficient of the national CCD indicated a decreasing trend, but imbalances remained, with the largest annual average value in the western region (0.120) and the smallest in the northeast (0.044). The main source of regional disparity was the intensity of transvariation. Accordingly, this study proposes targeted regional development strategies to promote low-carbon sustainable land use and improve the ability of land ecosystems to prevent security risks.
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Carbono , Ecossistema , China , Condições Sociais , Análise Espacial , Desenvolvimento Econômico , EficiênciaRESUMO
Purpose: Proliferative vitreoretinopathy (PVR) is the most common cause of failure of surgically repaired rhegmatogenous retinal detachment (RRD). Chemically induced and cell injection PVR models do not fully simulate the clinical characteristics of PVR in the post-RRD context. There is an unmet need for translational models in which to study mechanisms and treatments specific to RRD-PVR. Methods: RRD was induced in adult Dutch Belted rabbits. Posterior segments were fixed or processed for RNA sequencing at 6 hours and 2, 7, 14, and 35 days after induction. Histochemical staining and immunolabeling for glial fibrillary acidic protein, alpha smooth muscle actin, vascular endothelial growth factor receptor 2, CD68, and RPE 65 kDa protein were performed, and labeling intensity was scored. Single cell RNA sequencing was performed. Results: Acute histopathological changes included intravitreal and intraretinal hemorrhage, leukocytic vitritis, chorioretinitis, and retinal rarefaction. Chronic lesions showed retinal atrophy, gliosis, fibrotic subretinal membranes, and epiretinal fibrovascular proliferation. Fibrillar collagen was present in the fibrocellular and fibrovascular membranes in chronic lesions. Moderate to strong labeling of glia and vasculature was detected in chronic lesions. At day 14, most cells profiled by single cell sequencing were identified as MÏller glia and microglia, consistent with immunolabeling. Expression of several fibrillar collagen genes was upregulated in chronic lesions. Conclusions: Histological and transcriptional features of this rabbit model simulate important features of human RRD-PVR, including the transition to chronic intraretinal and periretinal fibrosis. This animal model of RRD with features of PVR will enable further research on targeted treatment interventions.
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Descolamento Retiniano , Vitreorretinopatia Proliferativa , Adulto , Animais , Humanos , Coelhos , Vitreorretinopatia Proliferativa/etiologia , Descolamento Retiniano/etiologia , Fator A de Crescimento do Endotélio Vascular , Modelos Animais , Fibrose , Colágenos FibrilaresRESUMO
Stress-related illnesses are linked to the onset and progression of renal diseases and depressive disorders. To investigate stress-induced changes in the renal transcriptome associated with the development of depressive behaviors, we generated here a chronic social defeat stress (CSDS) model of C57 BL/6 male mice and then performed RNA sequencing of the kidneys to obtain an inflammation-related transcriptome. Administration of the antidepressant drug fluoxetine (10 mg·kg-1 ·day-1 ) during CSDS induction could partially alleviate renal inflammation and reverse CSDS-induced depression-like behaviors. Moreover, fluoxetine also modulated gene expression of stress-related hormone receptors, including prolactin and melanin-concentrating hormone. These results suggest that CSDS can induce gene expression changes associated with inflammation in the kidney of C57 BL/6 male mice, and this inflammation can be treated effectively by fluoxetine.
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Antidepressivos , Fluoxetina , Animais , Camundongos , Masculino , Fluoxetina/farmacologia , Antidepressivos/farmacologia , Depressão/tratamento farmacológico , Depressão/metabolismo , Inflamação/tratamento farmacológico , RimRESUMO
Purpose: Proliferative vitreoretinopathy (PVR) is the most common cause of failure of retinal reattachment surgery, and the molecular changes leading to this aberrant wound healing process are currently unknown. Our ultimate goal is to study PVR pathogenesis by employing single-cell transcriptomics to dissect cellular heterogeneity. Design: Here we aimed to compare single-cell RNA sequencing (scRNA-seq) and single-nucleus RNA-sequencing (snRNA-seq) of retinal PVR samples in the rabbit model. Participants: Unilateral induction of PVR lesions in rabbit eyes with contralateral eyes serving as controls. Methods: Proliferative vitreoretinopathy was induced unilaterally in Dutch Belted rabbits. At different timepoints after PVR induction, retinas were dissociated into either cells or nuclei suspension and processed for scRNA-seq or snRNA-seq. Main Outcome Measures: Single cell and nuclei transcriptomic profiles of retinas after PVR induction. Results: Single-cell RNA sequencing and snRNA-seq were conducted on retinas at 4 hours and 14 days after disease induction. Although the capture rate of unique molecular identifiers and genes were greater in scRNA-seq samples, overall gene expression profiles of individual cell types were highly correlated between scRNA-seq and snRNA-seq. A major disparity between the 2 sequencing modalities was the cell type capture rate, however, with glial cell types overrepresented in scRNA-seq, and inner retinal neurons were enriched by snRNA-seq. Furthermore, fibrotic Müller glia were overrepresented in snRNA-seq samples, whereas reactive Müller glia were overrepresented in scRNA-seq samples. Trajectory analyses were similar between the 2 methods, allowing for the combined analysis of the scRNA-seq and snRNA-seq data sets. Conclusions: These findings highlight limitations of both scRNA-seq and snRNA-seq analysis and imply that use of both techniques together can more accurately identify transcriptional networks critical for aberrant fibrogenesis in PVR than using either in isolation. Financial Disclosures: Proprietary or commercial disclosure may be found after the references.
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With the advancement of additive manufacturing (AM), customized vascular stents can now be fabricated to fit the curvatures and sizes of a narrowed or blocked blood vessel, thereby reducing the possibility of thrombosis and restenosis. More importantly, AM enables the design and fabrication of complex and functional stent unit cells that would otherwise be impossible to realize with conventional manufacturing techniques. Additionally, AM makes fast design iterations possible while also shortening the development time of vascular stents. This has led to the emergence of a new treatment paradigm in which custom and on-demand-fabricated stents will be used for just-in-time treatments. This review is focused on the recent advances in AM vascular stents aimed at meeting the mechanical and biological requirements. First, the biomaterials suitable for AM vascular stents are listed and briefly described. Second, we review the AM technologies that have been so far used to fabricate vascular stents as well as the performances they have achieved. Subsequently, the design criteria for the clinical application of AM vascular stents are discussed considering the currently encountered limitations in materials and AM techniques. Finally, the remaining challenges are highlighted and some future research directions are proposed to realize clinically-viable AM vascular stents. STATEMENT OF SIGNIFICANCE: Vascular stents have been widely used for the treatment of vascular disease. The recent progress in additive manufacturing (AM) has provided unprecedented opportunities for revolutionizing traditional vascular stents. In this manuscript, we review the applications of AM to the design and fabrication of vascular stents. This is an interdisciplinary subject area that has not been previously covered in the published review articles. Our objective is to not only present the state-of-the-art of AM biomaterials and technologies but to also critically assess the limitations and challenges that need to be overcome to speed up the clinical adoption of AM vascular stents with both anatomical superiority and mechanical and biological functionalities that exceed those of the currently available mass-produced devices.
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Materiais Biocompatíveis , Doenças Vasculares , Humanos , Stents , TecnologiaRESUMO
A study on the polysorbate 80 stability in various formulation buffers commonly used in biopharmaceuticals was performed, to investigate the excipients influence on polysorbate 80 degradation. Polysorbate 80 is a common excipient in biopharmaceutical products. However, its degradation will potentially impact the drug product quality, and may trigger protein aggregation and particles formation. Due to the heterogeneity of the polysorbates and the mutual effects with other formulation compositions, the study of polysorbate degradation is challenging. Herein, a real-time stability study was designed and performed. The polysorbate 80 degradation trend was monitored by fluorescence micelle-based assay (FMA), reversed-phase-ultra-performance liquid chromatography-evaporative light scattering detector (RP-UPLC-ELSD) assay, and LC-MS assay. These assays provide orthogonal results to reveal both the micelle-forming capability and the compositional changes of polysorbate 80 in different buffer systems. The degradation occurred after a period of storage under 25 °C in different trend, which indicates the excipients could impact the degradation kinetics. Upon comparison, the degradation is prone to happen in histidine buffer than in acetate, phosphate or citrate buffers. LC-MS confirms oxidation as an independent degradation pathway with detection of the oxidative aldehyde. Thus, it is necessary to pay more attention to the excipients selection and their potential impact on polysorbate 80 stability to achieve longer shelf life for the biopharmaceuticals. Besides, the protective roles of several additives were figured out, which could be applied as potential industrial solutions to the polysorbate 80 degradation issues.
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Produtos Biológicos , Polissorbatos , Excipientes , Micelas , Cromatografia Líquida de Alta Pressão/métodos , Soluções TampãoRESUMO
Human retinal organoid transplantation could potentially be a treatment for degenerative retinal diseases. How the recipient retina regulates the survival, maturation, and proliferation of transplanted organoid cells is unknown. We transplanted human retinal organoid-derived cells into photoreceptor-deficient mice and conducted histology and single-cell RNA sequencing alongside time-matched cultured retinal organoids. Unexpectedly, we observed human cells that migrated into all recipient retinal layers and traveled long distances. Using an unbiased approach, we identified these cells as astrocytes and brain/spinal cord-like neural precursors that were absent or rare in stage-matched cultured organoids. In contrast, retinal progenitor-derived rods and cones remained in the subretinal space, maturing more rapidly than those in the cultured controls. These data suggest that recipient microenvironment promotes the maturation of transplanted photoreceptors while inducing or facilitating the survival of migratory cell populations that are not normally derived from retinal progenitors. These findings have important implications for potential cell-based treatments of retinal diseases.
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Degeneração Retiniana , Análise da Expressão Gênica de Célula Única , Humanos , Camundongos , Animais , Diferenciação Celular/fisiologia , Retina , Células Fotorreceptoras Retinianas Cones , Degeneração Retiniana/terapia , Organoides/transplanteRESUMO
The meninges, consisting of the pia, arachnoid, and dura layers, provide immunosurveillance of the central nervous system with both innate and adaptive immune cells. Here we present an optimized protocol for isolating dura leukocytes from neonatal and adult mice. We describe steps for harvesting the skull cap, extracting the dura mater, mechanical isolation of dura leukocytes, and flow cytometry analysis. Unlike the time-consuming enzymatic digestion isolation which makes dura hematopoietic stem cells (HSCs) undetectable, this rapid and simplified technique permits dura HSC identification. For complete details on the use and execution of this protocol, please refer to Niu et al. (2022).1.
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Background/purpose: A challenge that arises with periodontal regeneration surgery has been associated with the future development of periodontal regeneration membrane to prevent gingiva and fibroblasts invade the wound and allow alveolar bone successfully regenerated. Materials and methods: Chitosan (CS) has the advantages of non-toxicity, biodegradation, biocompatibility, and has been widely used in wound dressings. A flexible film was made using polyvinyl alcohol (PVA) blending CS based thermosensitive hydrogel. Results: The proposed 2% PVA/CS hydrogel has the highest swelling ratio about 720% after 60 min incubation and keeps its area after 10 min incubation for surgery suture. The elastic modulus of 0%, 1%, 2%, and 4% PVA/CS hydrogel were 7.75 ± 1.96, 0.91 ± 0.16, 0.75 ± 0.21, and 0.37 ± 0.06 MPa, respectively. The maximum strain of 2% PVA/CS hydrogel was 101.00 ± 28.03 (%). After 8 weeks biodegradation, the remain weight of 2% PVA/CS hydrogel was 71.36 ± 0.79 (%). Conclusion: In vitro cytotoxicity tests were performed and demonstrated PVA/CS hydrogel significantly improving cell proliferation. This study realized a promising flexible film for periodontal regeneration membrane that can prevent the rapid growth of fibroblasts to invade the wound and be used for periodontal regeneration surgery.
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Objective.X-ray scatter leads to signal bias and degrades the image quality in Computed Tomography imaging. Conventional real-time scatter estimation and correction methods include the scatter kernel superposition (SKS) methods, which approximate x-ray scatter field as a convolution of the scatter sources and scatter propagation kernels to reflect the spatial spreading of scatter x-ray photons. SKS methods are fast to implement but generally suffer from low accuracy due to the difficulties in determining the scatter kernels.Approach.To address such a problem, this work describes a new scatter estimation and correction method by combining the concept of SKS methods and convolutional neural network. Unlike conventional SKS methods which estimate the scatter amplitude and the scatter kernel based on the value of an individual pixel, the proposed method generates the scatter amplitude maps and the scatter width maps from projection images through a neural network, from which the final estimated scatter field is calculated based on a convolution process.Main Results.By incorporating physics in the network design, the proposed method requires fewer trainable parameters compared with another deep learning-based method (Deep Scatter Estimation). Both numerical simulations and physical experiments demonstrate that the proposed SKS-inspired convolutional neural network outperforms the conventional SKS method and other deep learning-based methods in both qualitative and quantitative aspects.Significance.The proposed method can effectively correct the scatter-related artifacts with a SKS-inspired convolutional neural network design.
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Artefatos , Processamento de Imagem Assistida por Computador , Processamento de Imagem Assistida por Computador/métodos , Imagens de Fantasmas , Espalhamento de Radiação , Método de Monte Carlo , Redes Neurais de Computação , Tomografia Computadorizada de Feixe Cônico/métodos , AlgoritmosRESUMO
Nitrogenous disinfection byproducts (N-DBPs), such as halocetamides (HAcAms), haloacetonitriles (HANs) and halonitromethanes (HNMs), are emerging DBPs in drinking water. They are more toxic than currently regulated DBPs, attracting more attention to their toxic effects and mechanism. In this study, human embryonic kidney (HEK) 293T cells were employed to explore the cytotoxicity of 29 N-DBPs. The influence of molecular structures and different halogenations on cytotoxicity has been comparatively analyzed. As toxicity is the downstream of chemico-biological interactions, the thiol reactivity of 29 N-DBPs has thus been evaluated by using glutathione (GSH) as a model nucleophile, which is the most prevalent cellular thiol and acts as an antioxidant to protect cells by detoxifying electrophilic compounds. Results show that the cytotoxicity of N-DBPs follows by the order of HAcAms > HANs > HNMs, which is different from their reactivity with GSH (the median of kGSH ranks as HNMs > HAcAms > HANs). However, a significant correlation (p < 0.001) between log kGSH and log IC50 (concentration causing 50% inhibition) has been respectively observed for HAcAms and HANs subset and HNMs subset, indicating such chemical reaction is a probable trigger for these DBPs to result in cytotoxicity. Finally, two separate quantitative structure - activity relationship (QSAR) models based on HANs & HAcAms subset and HNMs subset have been developed for estimating IC50 values. The good statistical performance makes the models possible to quickly and accurately predict IC50 values of other N-DBPs, providing basic data for their health risk assessment and greatly reducing in vivo and in vitro experiments.
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Desinfetantes , Água Potável , Poluentes Químicos da Água , Purificação da Água , Humanos , Desinfecção/métodos , Purificação da Água/métodos , Desinfetantes/toxicidade , Desinfetantes/química , Nitrogênio/química , Poluentes Químicos da Água/análise , Água Potável/análise , Halogenação , Compostos de SulfidrilaRESUMO
To achieve the goal of "carbon peak and carbon neutrality", it is crucial for China to effectively control environmental pollution in low-carbon action (LCA). Based on the evidence from 283 cities in China from 2007 to 2019, the difference-in-differences (DID) method is applied to explore the impact of LCA on pollutant emissions represented by the pilot of low-carbon city construction (LCCC) in China. The main findings are as follows. First of all, the LCCC suppresses pollution emissions, and the basic conclusions are still stable after endogenous treatment and robustness testing. Secondly, the mechanism analysis reveals that the main path of LCCC affecting pollution reduction comes from the progress of green technology and the upgrading of industrial structure. Finally, the heterogeneity analysis shows that the pollution reduction effect of the LCCC is better in the eastern region and cities with higher level of green economy development. Based on the policy standpoint of environmental protection, the LCCC has opened up a reasonable exploration path for China and other countries in the world to carry out effective pollution reduction.
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Poluentes Ambientais , Poluição Ambiental , Cidades , Carbono , China , Desenvolvimento Econômico , Dióxido de CarbonoRESUMO
The electrochemical performance of hybrid capacitors is seriously affected by the slow charging and discharging of the bulk phase. Here, Co-doped amorphous NiMoS4 modified with reduced graphene oxide (rGO) was prepared by a simple one-step hydrothermal method, and the obtained Co-doped NiMoS4/rGO nanocomposite (Ni1-xCoxMoS4/rGO) exhibits a high specific surface area, realizing the redox reaction from the bulk to the surface. Owing to the doping of Co with abundant redox active sites and the support of rGO sheets with high conductivity and a stable structure, the Ni1-xCoxMoS4/rGO anode assembled with an oxidized needle coke (NCO) cathode shows an excellent energy density of 28.9 W h kg-1 at a power density of 968.3 W kg-1. In addition, the hybrid supercapacitor displays a superior cycling performance with a capacity retention of 92.4% after 10 000 cycles. The construction of the Co-doped NiMoS4/rGO nanocomposite provides an effective strategy to boost the activity and stability of amorphous NiMoS4 for high-performance hybrid supercapacitors.
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Steady-state extramedullary hematopoiesis during adulthood is an emerging field of great interest. The meninges contain both innate and adaptive immune cells, which provide immunosurveillance of the central nervous system (CNS). Hematopoietic progenitors that give rise to meningeal immune cells remain elusive. Here, we report that steady-state meninges of adult mice host hematopoietic stem cells (HSCs), as defined by long-term, efficient, multi-lineage reconstitution and self-renewal capacity in the meninges, blood, spleen, and bone marrow of sublethally irradiated adult recipients. HSCs lodge in the meninges after birth with local expression of pro-hematopoietic niche factors. Meningeal HSCs are locally maintained in homeostasis and get replenished from the blood only when the resident pool is reduced. With a tissue-specific expression profile, meningeal HSCs can provide the CNS with a constant supply of leukocytes more adapted to local microenvironment.