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The insufficient charge separation and sluggish exciton transport severely limit the utilization of polymeric photocatalysts. To resolve the above issues, we incorporate bountiful carboxyl substituents within a novel benzodiimidazole oligomer and assemble it into a crystalline semiconductor. The photocatalyst is polar, hydrophilic, short-range crystalline, and capable of both hydrogen and oxygen evolution. The introduction of carboxyl side-groups adds asymmetry to the local structure and increases the built-in electric field. Further, accelerated carrier transfer is enabled via the short-range crystallinity. The superior hydrogen and oxygen production rates of 18.63 and 2.87 mmol g

Cerebrospinal fluid (CSF) is a clear fluid surrounding and nourishing the brain and spinal cord. Molecular profiling of the CSF is a common diagnostic approach for central nervous system (CNS) diseases, including infectious diseases, autoimmune disorders, brain hemorrhage and traumatic brain injury, CNS tumors, and Alzheimer’s disease1–10. Rodent models are critical for investigating CNS disease mechanisms and therapeutics, however, both collecting CSF and injecting materials into CSF in small animals are technically challenging and often result in high rates of postoperative mortality. Here, we present an easy-to-practice and cost-effective protocol with minimum instrument requirements to access the CSF in live rodents for collection and infusion purposes. By introducing a metal needle tool bent at a unique angle and length, we could steadily reach the CSF via the foramen magnum. Compared with prior methods, this protocol requires neither the operator to discern the changes in resistance from solid tissues while puncturing the needle, nor surgical opening of the skin and muscle covering the rodent neck. Using this method, we frequently obtain 5-15 μL of CSF from mice and 70-120 μL from rats to enable diverse downstream analyses including mass spectrometry. Due to the minimal invasiveness, this procedure allows iterative CSF collection from the same animal every few days – a major improvement over prior protocols that require extensive surgical operations. Moreover, we demonstrate that this method could be used for injecting desired solutions including dyes into mouse CSF with high success rates. Our method shortens the time required for CSF collection or injection to 3-5 minutes. Notably, we could reach near 100% postoperative recovery rates in both mice and rats even with repetitive collections. Together, we establish an efficient and minimally-invasive protocol for collecting CSF and inoculating reagents into the CSF in live rodents to enable various longitudinal studies at the forefronts of CNS investigation.

A promising strontium and cobalt-free ferrite Pr1-xCaxFeO3-δ (PCF, x = 0, 0.1, 0.2, 0.3, 0.4, 0.5) has been synthesized successfully by glycine-nitrate combustion method and used as the air electrode of solid oxide electrolysis cell (SOEC) for steam electrolysis. The crystal structure and electricity conductivity of PCF are investigated in detail. According to the conductivity test, Pr0.6Ca0.4FeO3-δ (PCF64) with higher conductivity is selected as the air electrode to preparing the single cell with structure of PCF64|GDC|SSZ|YSZ-NiO. Under SOFC mode, the maximum power density of the single cell is 462.93 mW cm−2 at 800 °C with hydrogen as fuel. Under SOEC mode, the current density reaches 277.14 mA cm−2 and the corresponding hydrogen production rates is 115.84 mL cm−2 h−1 at 800 °C at 1.3 V. In the 10 h short-term stability test, the cell shows good electrolysis stability.

The cathode of solid oxide electrolysis cell (SOEC) is used as a place for fuel gas electrolysis/co-electrolysis, and its performance significantly affects the efficiency of electrolysis. La0.75Sr0.25Cr0.5Mn0.5O3-δ (LSCM) is a potential SOEC cathode material due to its excellent redox stability and catalytic ability for fuel gas. An electrolyte-supported LSCM/YSZ/LSCM symmetrical cell and LSCM/YSZ/LSCF full cell were prepared and evaluated for high temperature steam electrolysis, carbon dioxide electrolysis and co-electrolysis. Under the applied voltage, both the symmetrical electrolysis cell and the full electrolysis cell can effectively electrolysis CO2 and H2O. During the experiment, by changing the operating conditions, the influence of different temperatures, concentration of CO2 and H2O, and applied voltage was studied to evaluate the electrochemical performance of SOEC. In order to further verify the long-term performance of SOEC, constant voltage was applied for co-electrolysis of CO2 and H2O. During the entire electrolysis process, the SOEC showed a stable current density of 0.1A·cm-2 under the applied voltage 1.5 V for more than 24 h.

Circadian biology modulates almost all aspects of mammalian physiology, disease, and response to therapies. Emerging data suggest that circadian biology may significantly affect the mechanisms of susceptibility, injury, recovery, and the response to therapy in stroke. In this review/perspective, we survey the accumulating literature and attempt to connect molecular, cellular, and physiological pathways in circadian biology to clinical consequences in stroke. Accounting for the complex and multifactorial effects of circadian rhythm may improve translational opportunities for stroke diagnostics and therapeutics.

Carbon-based perovskite solar cells are competitive candidate for photovoltaic applications in future due to their high-performance, low-cost and good stability. However, the hole transport materials are limited and their properties are not satisfying in carbon-based perovskite solar cells. Here, we report a typical p-type P3HT as hole transport layer for all low-temperature processed carbon-based perovskite solar cells with ZnO electron transport layer. Because P3HT has energy level matching with perovskite film and can facilitate the hole collection process, the power conversion efficiency of device can reach 16.05% that far higher than devices without P3HT hole transport layer. More importantly, due to good hydrophobicity and encapsulation function of P3HT, the stability of devices can also be significantly improved. The power conversion efficiency of device is able to retain over 90% of their initial value over 1200 h upon ambient air exposure without encapsulation. This present study provides a simple strategy for fabricating low-cost, highly efficient and stable perovskite solar cells.

Current diffusion in a finite width conductor plate is researched based on the traditional 1-D current diffusion in semi-infinite width conductor plate. The quasi-static magnetic field transient process of finite width conductor plate is studied, and we obtain the transient solution of the magnetic field and current diffusion, as well as the transient time constant. It is found that the current diffusion in a finite width conductor plate is a multiorder transient process, and the width of the conductor plate plays an important role in the current diffusion which affects the transient time constant. Only in the initial stage, the distributions of the magnetic field and current density in a finite width conductor plate can be approximated as the traditional 1-D current diffusion characteristics of a semi-infinite width conductor plate. In addition, the skin depth of current diffusion is the equivalent width of the equivalent resistance corresponding to loop voltage of the two semi-infinite conductor plates, which is not applicable to the analysis of conductor loss power and space magnetic field energy.

Abiotic stresses like drought affect plant growth and crop yield with climate change worsening. Stress associated proteins (SAPs), as the zinc finger proteins with A20/AN1 domain, play an important role in regulating abiotic stress response. As a typical summer dryland grain crop in the north of China, foxtail millet has the characteristics of drought resistance, making it a valuable resource for anti-stress gene exploitation and utilization. In this study, SiSAP4 gene was cloned from foxtail millet variety Yugu 1. Analysis showed that SiSAP4 gene was expressed in roots, stems and leaves at seedling stage, and the highest expression level was detected in leaves. Expression patterns under different stress conditions showed that expression level of SiSAP4 gene was significantly up-regulated under drought stress, suggesting it may be involved in drought stress response. Subcellular localization indicated that SiSAP4 was present in the nucleus and cytoplasm. It was revealed that SiSAP4 had no function in transcriptional activation in the yeast system. Overexpression of SiSAP4 in transgenic Arabidopsis resulted in enhanced tolerance to drought stress, which was simultaneously demonstrated by increased expression of a broad range of stress response genes. Based on those results, SiSAP4 has the potential to be used in transgenic breeding to improve drought stress tolerance in other crops. © 2021 Friends Science Publishers

In order to rescue neuronal function, neuroprotection should be required not only for the neuron soma but also the dendrites. Here, we propose the hypothesis that ephrin-B2-EphB2 signaling may be involved in dendritic degeneration after ischemic injury. A mouse model of focal cerebral ischemia with middle cerebral artery occlusion (MCAO) method was used for EphB2 signaling test in vivo. Primary cortical neuron culture and oxygen-glucose deprivation were used to assess EphB2 signaling in vitro. siRNA and soluble ephrin-B2 ectodomain were used to block ephrin-B2-Ephb2 signaling. In the mouse model of focal cerebral ischemia and in neurons subjected to oxygen-glucose deprivation, clustering of ephrin-B2 with its receptor EphB2 was detected. Phosphorylation of EphB2 suggested activation of this signaling pathway. RNA silencing of EphB2 prevented neuronal death and preserved dendritic length. To assess therapeutic potential, we compared the soluble EphB2 ectodomain with the NMDA antagonist MK801 in neurons after oxygen-glucose deprivation. Both agents equally reduced lactate dehydrogenase release as a general marker of neurotoxicity. However, only soluble EphB2 ectodomain protected the dendrites. These findings provide a proof of concept that ephrin-B2-EphB2 signaling may represent a novel therapeutic target to protect both the neuron soma as well as dendrites against ischemic injury.

Oral squamous cell carcinoma (OSCC) is a common malignant cancer with unfavorable prognosis, and the epithelial-to-mesenchymal transition (EMT) is a critical contributor to OSCC metastasis. Recently, we have shown that sirtuin 7 (Sirt7) is associated with EMT and OSCC metastasis by acetylating small mother against decapentaplegic 4 (Smad4). Nonetheless, the mechanism of Sirt7 downregulation in OSCC cells remains unknown. This study analyzed the potential microRNAs that were predicted to regulate Sirt7 expression by online databases. We identified miR-770 as an upstream regulator of Sirt7 that targets its 3'-untranslated region. The expression of miR-770 was observed to be negatively correlated with the mRNA expression of Sirt7 in metastatic OSCC tumors, and higher miR-770 expression was correlated with poorer OSCC patient survival. Our in vitro data indicated that miR-770 promoted OSCC cell migration and invasion, and this process was dependent on Sirt7/Smad4 signaling. Furthermore, in vivo metastasis experiments indicated that miR-770 overexpression led to more prominent OSCC metastasis and downregulated Sirt7 expression. Collectively, our results revealed a new role of Sirt7 downregulation in metastatic OSCC and suggested that miR-770 is a potential target in counteracting OSCC metastasis.

Mitochondria may be transferred from cell to cell in the central nervous system and this process may help defend neurons against injury and disease. But how mitochondria maintain their functionality during the process of release into extracellular space remains unknown. Here, we report that mitochondrial protein O-GlcNAcylation is a critical process to support extracellular mitochondrial functionality. Activation of CD38-cADPR signaling in astrocytes robustly induced protein O-GlcNAcylation in mitochondria, while oxygen-glucose deprivation and reoxygenation showed transient and mild protein modification. Blocking the endoplasmic reticulum – Golgi trafficking with Brefeldin A or slc35B4 siRNA reduced O-GlcNAcylation, and resulted in the secretion of mitochondria with decreased membrane potential and mtDNA. Finally, loss-of-function studies verified that O-GlcNAc-modified mitochondria demonstrated higher levels of neuroprotection after astrocyte-to-neuron mitochondrial transfer. Collectively, these findings suggest that post-translational modification by O-GlcNAc may be required for supporting the functionality and neuroprotective properties of mitochondria released from astrocytes.

Neuroprotectant strategies that have worked in rodent models of stroke have failed to provide protection in clinical trials. Here we show that the opposite circadian cycles in nocturnal rodents versus diurnal humans1,2 may contribute to this failure in translation. We tested three independent neuroprotective approaches—normobaric hyperoxia, the free radical scavenger α-phenyl-butyl-tert-nitrone (αPBN), and the N-methyl-d-aspartic acid (NMDA) antagonist MK801—in mouse and rat models of focal cerebral ischaemia. All three treatments reduced infarction in day-time (inactive phase) rodent models of stroke, but not in night-time (active phase) rodent models of stroke, which match the phase (active, day-time) during which most strokes occur in clinical trials. Laser-speckle imaging showed that the penumbra of cerebral ischaemia was narrower in the active-phase mouse model than in the inactive-phase model. The smaller penumbra was associated with a lower density of terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL)-positive dying cells and reduced infarct growth from 12 to 72 h. When we induced circadian-like cycles in primary mouse neurons, deprivation of oxygen and glucose triggered a smaller release of glutamate and reactive oxygen species, as well as lower activation of apoptotic and necroptotic mediators, in ‘active-phase’ than in ‘inactive-phase’ rodent neurons. αPBN and MK801 reduced neuronal death only in ‘inactive-phase’ neurons. These findings suggest that the influence of circadian rhythm on neuroprotection must be considered for translational studies in stroke and central nervous system diseases. Studies in rats and mice at different times of day suggest that the failure of neuroprotective strategies for stroke in translational studies might be related to the difference in circadian cycles between humans and rodents.

Advances in stem cell technology have provided three approaches to address the demanding issue of the treatment of intractable neurological disease. One of the approaches is the screening of compounds attenuating pathological phenotypes in stem-cell based models. A second approach consists of exogenous-targeted cell supplementation to the lesion with stem cell-derived differentiated cells. A third approach involves in vivo direct programming to transdifferentiate endogenous somatic cells and to boost CNS tissue remodeling. In this review, we outline research advances in stem cell technology of direct reprogramming in vitro and in vivo and discuss the future challenge of tissue remodeling by neural transdifferentiation.

Natural organic matter-iron (NOM-Fe) colloids are ubiquitous at anoxic-oxic interfaces of subsurface environments. Fe(II) or NOM can chemically reduce Cr(VI) to Cr(III), and the formation of Cr(III)-NOM-Fe colloids can control the fate and transport of Cr. We explored the formation and transport of Cr(III)-humic acid (HA)-Fe colloids upon reaction of Cr(VI) with HA-Fe(II) colloids over a range of environmentally relevant conditions. Cr(VI) was completely reduced by HA-Fe(II) complexes under anoxic conditions, and the formation of Cr(III)-HA-Fe colloids depended on HA concentration (or molar C/Fe ratio) and redox conditions. No colloids formed at HA concentrations below 3.5 mg C/L (C/Fe ratio below 1.6), but Cr(III)-HA-Fe colloids formed at higher HA concentrations. In column experiments, Cr(III)-HA-Fe(III) colloids formed under oxic conditions were readily transported through sand-packed porous media. Colloidal stability measurements further suggest that Cr(III)-HA-Fe colloids are highly stable and persist for at least 20 days without substantial change in particle size. This stability is attributed to the enrichment of free HA adsorbed on the Cr(III)-HA-Fe colloid surfaces, intensifying the electrostatic and/or steric repulsion interactions between particles. The new insights provided here are important for evaluating the long-term fate and transport of Cr in organic-rich redox transition zones.

Surface-functionalized Mn–Fe oxide nanocrystals (NCs) were evaluated for single- and multi-sorbate scenarios considering As(V), Cr(VI), and U(VI) in varied water chemistries (deionized (DI), ground, and sea water) at pH 7.0. Multi-sorbate scenarios were further examined for competitive and/or cooperative effects. Precisely synthesized manganese ferrite (MnFe2O4) NCs were compared with iron oxide (Fe3O4) and manganese oxide (MnxOy) nanocrystal cores in terms of sorption capacities and colloidal stabilities. Positively charged cetyltrimethylammonium bromide (CTAB) and negatively charged oleyl phosphate (OP) were evaluated and compared as organic coatings. MnFe2O4 NCs exhibited both enhanced sorption performance and colloidal stability compared with Fe3O4 and MnxOy NC cores when functionalized with the same surfactant coating. For MnFe2O4 NCs, maximum sorption of As(V), Cr(VI), and U(VI) were observed to be 2.62, 3.43, and 4.27 mmol g−1, respectively (in DI water). Relative sorption capacity enhancement (compared with Fe3O4 and MnxOy) is due to increased surface grafting densities of MnFe2O4 NCs, providing a larger number of sorption sites (functional group) for target sorbates and higher repulsive energy (osmotic and elastic–steric interaction) for increased stability, and thus maintaining available surface area. For As(V) and Cr(VI) multi-sorbate systems, all materials evaluated preferentially adsorbed As(V) over Cr(VI). This preference was further investigated and observed using a novel quartz crystal microbalance (QCM) technique.

Background LncRNA LINC00662 is closely related to the occurrence and development of cancer. This study aims to explore the effect of LINC00662 on colon cancer tumor growth and metastasis and its molecular mechanism. Methods CCK8, colony formation, transwell, scratch wound, TUNEL, flow cytometry, RT-PCR, western blotting and immunohistochemistry assays were used to detect the proliferation, apoptosis, invasion and migration of colon cancer cell and mRNA and protein expressions. Luciferase reporter and RNA pull down assays were used to detect the combination of LINC00662 and miR-340-5p or IL22 and the combination of miR-340-5p and CLDN8/IL22. Co-immunoprecipitation were used to detect the co-expression of CLDN8 and IL22 in colon cell lines. The targets of LINC00662 were predicated by Starbase v2.0. The target genes of miR-340-5p were predicated by miRDB and TargetScan. GO and KEGG enrichment analysis were performed by DAVID website. Results LINC00662 was up-regulation in colon cancer tissues and cell lines. Univariate Cox regression analysis showed that the LINC00662 expression level was related to the poor prognosis. LINC00662-WT and miR-340-5p mimics co-transfection depressed luciferase activity and IL22/CLDN8-WT and miR-340-5p inhibitors co-transfection memorably motivated luciferase activity. LINC00662 overexpression promoted cell proliferation, invasion and migration, and inhibited cell apoptosis in colon cancer. In vivo xenograft studies in nude mice manifested that LINC00662 overexpression prominently accelerate tumor growth. There was an opposite reaction in the biological functions of colon cells and tumor growth between LINC00662 overexpression and LINC00662 inhibition in vitro and in vivo. The functions of miR-340-5p mimics regulating the biological functions of colon cells and tumor growth were consistent with those of LINC00662 inhibition. CLDN8 and IL22, as target genes of miR-340-5p, reversed the functions of LINC00662 affecting the biological functions of colon cells and the protein levels of Bax, Bcl-2, XIAP, VEGF, MMP-2, E-cadherin and N-cadherin. Co-immunoprecipitation experiments indicated that CLDN8 directly interact with IL22 in colon cell lines. LINC00662 regulated CLDN8 and IL22 expressions and the activation of ERK signaling pathway via targeting miR-340-5p. Conclusion LINC00662 overexpression promoted the occurrence and development of colon cancer by competitively binding with miR-340-5p to regulate CLDN8/IL22 co-expression and activating ERK signaling pathway.

A highly crystalline perylene imide supramolecular photocatalyst (PDI-NH) is synthesized via imidazole solvent method. The catalyst shows a breakthrough oxygen evolution rate (40.6 mmol g

Promoting angiogenesis to restore circulation to the ischemic tissue is still an important therapeutic target in stroke. Here, we ask whether the Ca2+-regulated, phospholipid-and membrane-binding protein-Annexin A2 (ANXA2) may regulate angiogenesis after stroke.Compared with wild type (WT) mice, the density of microvessels in brain and the number of new vessels sprouting from aortic ring were significantly increased in Anxa2 knock-in (ANXA2+/+) mice. After focal cerebral ischemia, proliferation of brain endothelial cells in ANXA2+/+ mice was significantly elevated at 7 days post-stroke, which further improved behavioral recovery. To assess the pro-angiogenic mechanisms of ANXA2, we used brain endothelial cells cultures to investigate its effects on cell tube-formation and migration. Recombinant ANXA2 increased tube-formation and migration of brain endothelial cells either under normal condition or after OGD injury. These protective effects of recombinant ANXA2 were regulated by interaction with ANXA2 receptor (A2R), and the ability of ANXA2-A2R to activate AKT/ERK pathways. Taken together, our study indicates that ANXA2 might be involved in angiogenesis after ischemic stroke. Further investigation of ANXA2-A2R will provide a new therapeutic target for stroke.

Atherosclerosis is the main pathological basis for the occurrence of most cardiovascular diseases, the leading global health threat, and a great burden for society. It has been well established that atherosclerosis is not only a metabolic disorder but also a chronic, sterile, and maladaptive inflammatory process encompassing both innate and adaptive immunity. Macrophages, the major immune cell population in atherosclerotic lesions, have been shown to play critical roles in all stages of atherosclerosis, including the initiation and progression of advanced atherosclerosis. Macrophages have emerged as a novel potential target for antiatherosclerosis therapy. In addition, the macrophage phenotype is greatly influenced by microenvironmental stimuli in the plaques and presents complex heterogeneity. This article reviews the functions of macrophages in different stages of atherosclerosis, as well as the phenotypes and functions of macrophage subsets. New treatment strategies based on macrophage-related inflammation are also discussed.

Iron oxide-based nanomaterials have received considerable research interests due to their unique physical and chemical properties. This review offers a brief account of the current knowledge regarding engineered iron oxide-based nanomaterials for environmental applications, focusing on the synthesis, surface modification, and metal removal. We begin by discussing recent advances in synthesis methods for hierarchically structured, iron oxide nanocomposites. Size, shape, as well as structure of iron oxide-based nanomaterials can be tailored through tuning specific reaction conditions. Further, both organic and inorganic coating strategies are introduced, which can be employed to render such nanomaterials water stable while also allowing for specific (surface) functionality. Lastly, adsorption of single- and multi-contaminants, considering metals/metalloids as well as rare earth elements, onto representative iron oxide-based nanomaterials is summarized and compared.

A dual-porphyrin heterostructure is successfully constructed by coupling tetrakis (4-carboxyphenyl) zinc porphyrin (ZnTCPP) with tetrakis (4-hydroxyphenyl) porphyrin (THPP). The high photocatalytic H2 evolution rate of 41.4 mmol h-1 g-1 is obtained for ZnTCPP/THPP under full spectrum, which is ≈5.1 and ≈17.0 times higher than that of pure ZnTCPP and THPP, respectively. The significantly enhanced activity is mainly attributed to the giant interfacial electric field formed between dual porphyrins, which greatly facilitates efficient charge separation and transfer. Meanwhile, similar conjugated structures of dual porphyrins also provide proper interface match and decrease interface defects, thus inhibiting the recombination of photoproduced carriers. By rationally combining the appropriate band structures and high-quality interfacial contact of dual porphyrins, this work provides a fresh insight into the interfacial electric field construction to improve the photocatalytic performance.

The concept of the neurovascular unit emphasizes the importance of cell-cell signaling between neural, glial, and vascular compartments. In neurogenesis, for example, brain endothelial cells play a key role by supplying trophic support to neural progenitors. Here, we describe a surprising phenomenon where brain endothelial cells may release trans-differentiation signals that convert astrocytes into neural progenitor cells in male mice after stroke. After oxygen-glucose deprivation, brain endothelial cells release microvesicles containing pro-neural factor Ascl1 that enter into astrocytes to induce their trans-differentiation into neural progenitors. In mouse models of focal cerebral ischemia, Ascl1 is upregulated in endothelium prior to astrocytic conversion into neural progenitor cells. Injecting brain endothelial-derived microvesicles amplifies the process of astrocyte trans-differentiation. Endothelial-specific overexpression of Ascl1 increases the local conversion of astrocytes into neural progenitors and improves behavioral recovery. Our findings describe an unexpected vascular-regulated mechanism of neuroplasticity that may open up therapeutic opportunities for improving outcomes after stroke.

Background and Purpose: Inflammatory mediators in blood have been proposed as potential biomarkers in stroke. However, a direct relationship between these circulating factors and brain-specific ischemic injury remains to be fully defined. Methods: An unbiased screen in a nonhuman primate model of stroke was used to find out the most responsive circulating biomarker flowing ischemic stroke. Then this phenomenon was checked in human beings and mice. Finally, we observed the temporospatial responsive characteristics of this biomarker after ischemic brain injury in mice to evaluate the direct relationship between this circulating factor and central nervous system–specific ischemic injury. Results: In a nonhuman primate model, an unbiased screen revealed CCL2 (C-C motif chemokine ligand 2) as a major response factor in plasma after stroke. In mouse models of focal cerebral ischemia, plasma levels of CCL2 showed a transient response, that is, rapidly elevated by 2 to 3 hours postischemia but then renormalized back to baseline levels by 24 hours. However, a different CCL2 temporal profile was observed in whole brain homogenate, cerebrospinal fluid, and isolated brain microvessels, with a progressive increase over 24 hours, demonstrating a mismatch between brain versus plasma responses. In contrast to the lack of correlation with central nervous system responses, 2 peripheral compartments showed transient profiles that matched circulating plasma signatures. CCL2 protein in lymph nodes and adipose tissue was significantly increased at 2 hours and renormalized by 24 hours. Conclusions: These findings may provide a cautionary tale for biomarker pursuits in plasma. Besides a direct central nervous system response, peripheral organs may also contribute to blood signatures in complex and indirect ways.

Environmental microplastic accumulation can lead to a range of problems and the potential loss of ecosystem services. However, the impacts of microplastics on sediment environmental properties and microbial ecosystems remain unclear. Therefore, this article aimed to better elucidate the effects of microplastics on sediment physicochemical properties, enzymatic activities and the diversity and composition of sediment microbial communities. We conducted a 60-day sediment-incubation experiment using sediments with three concentrations (2%, 5%, and 10%, w/w) and two types (polyethylene (PE) and polyvinyl chloride (PVC)) of microplastics (550 μm) in a climate-controlled chamber. The addition of both PE and PVC microplastics reduced sediment catalase, polyphenol oxidase (PO), and urease activities, and decreased physicochemical indicators, including total organic carbon (TOC), total nitrogen (TN), and pH value. In addition, microplastics reduced bacterial community diversity and inhibited the recovery of community richness, implying that microplastics may compete with sediment microorganisms for niches. Stronger effects were generally detected under a high microplastic concentration (10%), reflecting the influence of the concentration of microplastic exposure on the bacterial community. The dominant bacterial phyla were Chloroflexi, Proteobacteria, Bacteroidota, Firmicutes, and Actinobacteriota, and the relative abundances of Proteobacteria, and Bacteroidota significantly increased in the microplastic treatments during the late incubation period, indicating that microplastic addition may have improved nutritional conditions later in the incubation process. Structural equation modeling indicated that shifts in PO activity had a significant correlation with changes in Proteobacteria abundance (P 0.01), and important drivers affecting the dissimilarity of Bacteroidota abundance were the changes of TN content and catalase activity (P 0.05). These results indicated that microplastics with diverse characteristics affected the environmental properties of the sediment, while the physicochemical properties and enzymatic activity of the sediment could directly or indirectly exert different impacts on the dominant bacteria. This study can provide a theoretical basis for the ecological effects of microplastic contamination.

Background MR (Magnetic resonance) peritoneography is sensible for continuous ambulatory peritoneal dialysis (CAPD)-related complications, which could offer excellent soft-tissue contrast and allows a multiplanar imaging evaluation of complications. However, there is no study about the optimal concentration of the gadolinium-based agents nor the side effects of gadolinium-based agents on peritoneum and residual renal function. Method Five different groups of uremic rats and two groups of normal rats were injected with a 40-ml mixture of peritoneal dialysate and gadolinium-based agents at varying concentrations prior to MR peritoneography. Thereafter, MR image obtained was evaluated by two experienced radiologists blinded to the concentrations. Peritoneal morphology and thickness of the uremic rats were also assessed using hematoxylin and eosin and Masson staining. Residual renal function was evaluated using serum creatinine levels and hematoxylin and eosin (HE) staining of pathological kidney sections. Results and conclusion The gadolinium-based agents used in this experiment have no significant effect on residual renal function. There is no obvious difference in the image quality at the different gadolinium-based agents concentration. Due to the adverse effects of gadolinium-based agents in the previous studies, we suggest reducing the dose of gadolinium-based agents during MR peritoneography to the lowest limits.

The operating conditions of wastewater treatment process is time-varying and nonlinear. In the study of biochemical reaction process, there are coupling relations and size differences among variables of non-single controlled objects. In order to solve the multi-variable control problem, this paper use the Model Predictive Control (MPC) based on neural network. A number of control factors are considered in the design process and by constructing the cost function, the controller is developed in the expected direction. In addition, at the actual working condition change, the single working condition change is very difficult to maintain for a long time. In this paper, a multi-condition identification model predictive control is established by using T-S model. The scheme can make the controller more fit with the change of state. In order to verify the effectiveness of the designed controller and guarantee the data authenticity, the multi-state condition of this paper is constructed by using the real data provided by BSM1.The experimental results show that the designed controller is more stable at single condition and multi-condition, and the control accuracy has been improved obviously. The advantages of the controller are also illustrated by the evaluation indexes of IAE (Integral Absolute Error) and ISE (Integral Square Error).

Hole-conductor-free carbon-based perovskite solar cells (C-PSCs) are known for their low-cost and superstability. In this work, different mesoporous structures, namely, mesoporous TiO2 + Al2O3 (mp-TiO2 + Al2O3), mp-TiO2 + ZrO2, mp-Al2O3, mp-TiO2, and blocking compact layer of TiO2 (bl-TiO2), were investigated and systematically compared. Results revealed that the performance of PSCs with double-layer mesoporous structure was better than that of the other mesoporous structures, especially PSC with the structure of mp-TiO2 + Al2O3 obtained the open-circuit voltage (Voc) of 0.97 V and the current density (Jsc) of 23.77 mA cm−2, respectively, the photoelectric conversion efficiency (PCE) reached 11.3% because of the function of the mesoporous layer in separating TiO2 and carbon, thereby avoiding direct contact and reducing the leakage of the current. Al2O3 and ZrO2 are insulating materials that could effectively prevent electrons from transmitting back to C. The mesoporous structure of the device based on mp-TiO2 + Al2O3 was evenly distributed, the perovskite crystal particles based on mp-TiO2 + Al2O3 were enlarged, uniform, and relatively tight, and the grain boundaries between the perovskite crystal particles were remarkably reduced. Among the films, the perovskite film of mp-TiO2 + Al2O3 structure had the highest absorption intensity. This study provided a new basis for commercializing low-cost PSCs.

Objectives To assess the correlation between endorectal ultrasound (ERUS) and magnetic resonance imaging (MRI) in predicting the circumferential resection margin (CRM) status of patients with mid-low rectal cancer without preoperative chemoradiotherapy. Methods Twenty patients with rectal cancer who did not receive preoperative chemoradiotherapy and underwent ERUS and MRI examinations before total mesorectal excision from May 2018 to April 2019 were included in this study. The patient and tumor characteristics, lymph nodes, tumor stages, ERUS and MRI predictors of the CRM status, and postoperative pathologic results were recorded. The closest distance between the deepest portion of lesion invasion and the mesorectal fascia was independently measured on MRI and ERUS images by 2 observers. The observers were blinded to the pathologic results. Measurements from ERUS and MRI were compared. Results The mean distance between the distal edge of the lesion and the anal verge was 5.7 cm (range, 3.1-8.1 cm). The ERUS and pathologic evaluations of CRM involvement were consistent in 90% of the cases. The MRI and pathologic evaluations of CRM involvement were concordant in 95% of the cases. The Cohen κ coefficient of ERUS and MRI was 0.608 (P = .007). The correlation coefficient of ERUS and MRI for assessing the closest distance from the edge of cancer invasion to the mesorectal fascia was 0.99 (P = .0005). Conclusions Endorectal ultrasound and MRI assessments of the preoperative CRM status appear to be highly consistent. Endorectal ultrasound can be used as a complementary tool with MRI to predict the CRM status of patients with mid-low rectal cancer without preoperative chemoradiotherapy.

A composite film was prepared by mixing NaLuF4:Yb3+/Er3+ up-conversion luminescent material with commercial P25, and a scattering layer composed of flower-like TiO2 was added on to the composite film (UC/P25) to form a double-layer composite film (UC/P25 + FT). An AgNO3 solution was irradiated by ultraviolet light to deposit nano-Ag particles on the prepared double-layer film, and a nano-Ag modified double-layer film (UC/P25 + FT + Ag) was finally obtained. The synergistic effect of the three improved methods conferred the UC/P25 + FT + Ag film with a wide spectral absorption range, strong light-scattering ability, and strong light absorption capability, which greatly improved the photoelectric performance of the film. The maximum photoelectron conversion efficiency of dye-sensitized solar cells with the UC/P25 + FT + Ag photoanode reached up to 8.14%, which increased by 32.36% compared with that of the pure P25 film photoelectrode.

Surface-functionalized magnetic nanoparticles are promising adsorbents due to their large surface areas and ease of separation after contaminant removal. In this work, the affinity of Cr(VI) adsorption to 8 nm surface-functionalized superparamagnetic magnetite nanoparticles was determined for surface coatings with amine (trimethyloctadecylammonium bromide, CTAB) and carboxyl (stearic acid, SA) functional groups. Cr(VI) adsorbed more strongly to the CTAB-coated nanoparticles than to the SA-coated materials due to electrostatic interactions between positively charged CTAB and anionic Cr(VI) species. The adsorption of Cr(VI) by CTAB- and SA-coated nanoparticles increased with decreasing pH (4.5-10), which could be simulated by a surface complexation model. Cr(VI) removal performance by the nanocomposite was evaluated for two realistic drinking water compositions. The co-occurrence of divalent cations (Ca2+ and Mg2+) and Cr(VI) resulted in decreased Cr(VI) adsorption as particles were destabilized, leading to the aggregation and lower effective surface area, confirming the importance of the overall water composition on the performance of novel engineered nanomaterials for water treatment applications.

Here we present a study on the quenchability of hydrous mafic melts. We show via hydrothermal experiments that the ability to quench a mafic hydrous melt to a homogeneous glass at cooling rates relevant to natural samples has a limit of no more than 9 ± 1 wt% of dissolved H2O in the melt. We performed supra-liquidus experiments on a mafic starting composition at 1–1.5 GPa spanning H2O-undersaturated to H2O-saturated conditions (from ~1 to ~21 wt%). After dissolving H2O and equilibrating, the hydrous mafic melt experiments were quenched. Quenching rates of 20 to 90 K/s at the glass transition temperature were achieved, and some experiments were allowed to decompress from thermal contraction while others were held at an isobaric condition during quench. We found that quenching of a hydrous melt to a homogeneous glass at quench rates comparable to natural conditions is possible at water contents up to 6 wt%. Melts containing 6–9 wt% of H2O are partially quenched to a glass, and always contain significant fractions of quench crystals and glass alteration/devitrification products. Experiments with water contents greater than 9 wt% have no optically clear glass after quench and result in fine-grained mixtures of alteration/devitrification products (minerals and amorphous materials). Our limit of 9 ± 1 wt% agrees well with the maximum of dissolved H2O contents found in natural glassy melt inclusions (8.5 wt% H2O). Other techniques for estimating pre-eruptive dissolved H2O content using petrologic and geochemical modeling have been used to argue that some arc magmas are as hydrous as 16 wt% H2O. Thus, our results raise the question of whether the observed record of glassy melt inclusions has an upper limit that is partially controlled by the quenching process. This potentially leads to underestimating the maximum amount of H2O recycled at arcs when results from glassy melt inclusions are predominantly used to estimate water fluxes from the mantle.

Direct arylation polymerization (DARP) is a novel approach to obtain conjugated polymers (CPs) through the straightforward C-H activation of monomer building blocks. In this work, a convenient DARP method with high efficiency and excellent regioselectivity is developed to synthesize a series of donor-acceptor (D-A)-type CPs composed of electron-acceptor moiety fluorenones (FOs) and various electron-donor moieties. CPs with different band gaps are obtained in good yields and display large Stokes shifts up to 295 nm. Two ionic CPs, PFOP-NEt3(+) and PFOP-COO(-), were prepared in a polar solvent system to improve the water solubility and biocompatibility using the proposed DARP method. Detailed photophysical studies of these two CPs suggest that both solvation and hydrogen bonds play important roles in determining the polymers' spectroscopic properties. Further studies of the cationic polymer PFOP-NEt3(+) in cell imaging demonstrate its potential application in labeling cell membranes and lysosomes given its low cytotoxicity, excellent photostability, and specific subcellular localization.

Background Claudin 8 (CLDN8), an integral membrane protein that constitutes tight junctions in cell membranes, was recently implicated in tumor progression. However, its roles in colorectal cancer (CRC) progression and metastasis remain unknown. Methods In this study, we examined the effect of CLDN8 on the progression of CRC, including cell proliferation, migration, and invasion, and determines its underlying molecular mechanism using in vitro CRC cell lines and in vivo mouse xenograft models. Results We found that CLDN8 expression in human CRC tissues was significantly higher than that in adjacent normal tissues. The knockdown of CLDN8 markedly suppressed the proliferation, migration, and invasion of SW480 and HT-29 CRC cells, whereas the overexpression of CLDN8 notably promoted tumor progression in SW480 and HT-29 CRC cells. Mechanistic studies revealed that CLDN8 upregulated p-ERK (p-PKB/AKT) and MMP9 in CRC cells. Notably, the MAPK/ERK inhibitor PD98095 dramatically attenuated the effects of CLDN8 on p-ERK and MMP9. Moreover, PD98095 remarkably blocked the tumor-promoting activity of CLDN8. The knockdown of CLDN8 also inhibited the in vivo tumor growth in a nude mouse xenograft model. Collectively, CLDN8 promoted CRC cell proliferation, migration, and invasion, at least in part, by activating the MAPK/ERK signaling pathway. Conclusion These findings suggest that CLDN8 exhibits an oncogenic effect in human CRC progression.

While the reaction mechanisms between ferrihydrite and sulfide are well-documented, the role of redox reactions on the particle-particle stability of ferrihydrite colloids is largely overlooked. Such reactions are critical for a number of (bio)geochemical processes governing ferrihydrite-based colloid processing and their associated role in nutrient and contaminant subsurface dynamics. Taking a fundamental colloid chemistry approach, along with a complementary suite of characterization techniques, here, we explore the stability mechanisms of ferrihydrite colloids over a wide range of environmentally relevant sulfide concentrations at pH 6.0. Results show that sulfide lowered the stability of both ferrihydrite colloids in a concentration-dependent fashion. At lower sulfide concentrations (15.6-62.5 μM), ferrihydrite colloids are apparently stable, but their critical coagulation concentration (CCC) in NaCl linearly decreases with increasing sulfide concentration. This is attributed to the formation of negatively charged elemental sulfur (S(0)) nanoparticles on the surfaces of positively charged ferrihydrite, intensifying the electrostatic attractions between oppositely charged regions on adjacent ferrihydrite surfaces. Further increasing sulfide concentration generates more S(0) attaching to the ferrihydrite surface. This results in effective surface charge neutralization and then subsequent charge reversal, leading to extensive aggregation of ferrihydrite (core) colloids. Interestingly, for the ferrihydrite colloids with higher hydrodynamic diameter, aggregation rates linearly decreases with increasing sulfide concentration from 156.3 to 312.5 μM, which is likely due to the formation of substantial amounts of negatively charged S(0) and FeS. Findings highlight the significance of sulfidation products in controlling the stability of ferrihydrite colloids in sulfidic environments.

The transformations of water-stable C60 clusters (nC60) to oxidized C60 derivatives via photoreactions and ground-state reactions have been described as critical processes in understanding the ultimate environmental fate of fullerene-based materials. However, (photo)oxidation of aqueous-based C60 (as water stable, nanoscale aggregates termed nC60) with hydrogen peroxide (H2O2) and/or hydroxyl radical ( OH), common environmental oxidants, has not been fully explored. To address this, the aqueous physicochemical transformations of C60 (as nC60 aggregates) in the presence of H2O2 and/or OH in both photoexcited-state and ground-state under environmentally relevant conditions are quantitatively described. Results show that nC60 undergoes facile oxidation in the presence of H2O2 under UVA irradiation but not under dark conditions, and the oxidation reaction rates increase with effective OH concentration (via photodecomposition of H2O2), while being inversely related to solution pH. Product characterization via dynamic light scattering, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, total organic carbon, high-performance liquid chromatography, and octanol-water partition experiments collectively describe resulting C60 derivatives with new covalent oxygen functionality which are also relatively more hydrophilic. For all cases, photoirradiation was observed to significantly enhanced the rates and extent of C60 oxidation.

A three-dimensional (3D) graphene/self-assembled perylene imide (rGO/PDI) aerogel composite has been successfully constructed via a simple low-temperature hydrothermal method in this work. The 3D rGO/PDI composite exhibited superior visible-light photocatalytic performance. The removal rate was respectively 2.46 times and 3.33 times higher than that of PDI in static and dynamic catalytic systems. The satisfactory activity is mainly attributed to the more effective separation of electron–hole pairs. To be specific, the self-assembled PDI nanofibers and graphene are effectively combined via non-covalent π-π interaction. The π-π interaction enhances the long-range π-electrons delocalization and electron coupling effects, which is beneficial for the carrier mobility and the separation of electron–hole pairs. Meanwhile, the three-dimensional structure of graphene provides a fast multidimensional channel for electron transfer and effectively improves the adsorption capacity of PDI due to the large specific surface area. What’s more, the rGO/PDI composite exhibits great stability than the pure PDI. Overall, this work provides a new insight into improving the photocatalytic activity of self-assembled organic materials.

Herein, an efficient full-spectrum responsive p-Ag2S/n-PDI (perylenediimide) heterojunction was successfully constructed. The self-assembled PDI nanostructure was formed via hydrogen bonding and π–π stacking. Ag2S quantum dots were tightly loaded onto the surface of PDI nanofibers via a two-step electrostatic process. When the mass ratio of Ag2S to PDI was 1 : 0.6, the p-Ag2S/n-PDI heterojunction showed optimum photocatalytic properties. The full-spectrum photocatalytic activity of p-Ag2S/n-PDI was found to be 5.13 and 1.79 times higher than pure PDI for phenol degradation and O2 evolution, respectively. The results showed that Ag2S quantum dots promoted the well-organized π–π stacking degree of the self-assembled PDI, which was helpful for the migration of photo-generated electrons along the quasi-one-dimensional π–π stacking of PDI. Simultaneously, Ag2S quantum dots were found to enhance the light absorption of Ag2S/PDI. More interestingly, the p-Ag2S/n-PDI heterojunction exhibited excellent photoelectric properties, indicating more effective separation of carriers, which arose as a result of the built-in electric field between the Ag2S and PDI. Besides this, the p-Ag2S/n-PDI heterojunction produces more active species than pure PDI, resulting in a much stronger oxidation ability. This work details some interesting ideas for designing efficient heterojunction photocatalysts that have a supramolecular organic nanostructure.