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1.
Sci Adv ; 10(18): eadl5067, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38701201

RESUMO

Airborne pathogens retain prolonged infectious activity once attached to the indoor environment, posing a pervasive threat to public health. Conventional air filters suffer from ineffective inactivation of the physics-separated microorganisms, and the chemical-based antimicrobial materials face challenges of poor stability/efficiency and inefficient viral inactivation. We, therefore, developed a rapid, reliable antimicrobial method against the attached indoor bacteria/viruses using a large-scale tunneling charge-motivated disinfection device fabricated by directly dispersing monolayer graphene on insulators. Free charges can be stably immobilized under the monolayer graphene through the tunneling effect. The stored charges can motivate continuous electron loss of attached microorganisms for accelerated disinfection, overcoming the diffusion limitation of chemical disinfectants. Complete (>99.99%) and broad-spectrum disinfection was achieved <1 min of attachment to the scaled-up device (25 square centimeters), reliably for 72 hours at high temperature (60°C) and humidity (90%). This method can be readily applied to high-touch surfaces in indoor environments for pathogen control.


Assuntos
Desinfecção , Eletrônica , Grafite , Desinfecção/métodos , Eletrônica/métodos , Grafite/química , Viabilidade Microbiana , Bactérias
2.
Bioresour Technol ; 399: 130644, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38552856

RESUMO

To address the low-carbon treatment requirements for municipal wastewater, a novel anaerobic acidification membrane bioreactor (AAMBR) was developed for recovering organic matter in terms of volatile fatty acids (VFAs). While the AAMBR successfully generated VFAs from municipal wastewater through forward osmosis (FO) membrane concentration, its operation was limited to a single pH value of 10.0. Here, performance of the AAMBR operating at acidic condition was evaluated and compared with that at alkaline condition. The findings revealed that the AAMBR with pH 5.0 efficiently transformed organic matter into acetic acid, propionic acid, and butyric acid, resulting in a VFAs yield of 0.48 g/g-CODfeed. In comparison with the AAMBR at pH 10.0, this study achieved a similar VFAs yield, a lower fouling tendency, a lower loss of nutrients and a lower controlling cost. In conclusion, this study demonstrated that a pH of 5.0 is optimal for the AAMBR treating municipal wastewater.


Assuntos
Reatores Biológicos , Águas Residuárias , Anaerobiose , Ácidos Graxos Voláteis , Concentração de Íons de Hidrogênio , Membranas Artificiais
3.
Water Res ; 254: 121378, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38430758

RESUMO

This study delved into the efficacy of sludge digestion and the mechanisms involved in sludge destruction during the implementation of forward osmosis process for sludge thickening and digestion (FO-MSTD). Utilizing a lab-scale FO membrane reactor for the thickening and digestion of waste activated sludge (WAS), the investigation explored the effects of sludge thickening and digestion in FO-MSTD processes using draw solutions of varying concentrations. The findings underscored the significance of hydraulic retention time (HRT) as a pivotal parameter influencing the swift thickening or profound digestion of sludge. Consequently, tailoring the HRT to specific processing objectives emerged as a key strategy for achieving desired treatment outcomes. In the investigation, the use of a 1 M NaCl draw solution in the FO-MSTD process showcased enhanced thickening and digestion capabilities. This specific setup raised the concentration of mixed liquor suspended solids (MLSS) to over 30 g/L and achieved a 42.7% digestion efficiency of mixed liquor volatile suspended solids (MLVSS) within an operational timeframe of 18 days. Furthermore, the research unveiled distinct stages in the sludge digestion process of the FO-MSTD system, characterized by fully aerobic digestion and aerobic-local anaerobic co-existing digestion. In the fully aerobic digestion stage, the sludge digestion rate exhibited a steady increase, leading to the breakdown of sludge floc structures and the release of a substantial amount of nutrients into the sludge supernatant. The predominant microorganisms during this stage were typical functional microorganisms found in wastewater treatment systems. Transitioning into the aerobic-local anaerobic co-existing digestion stage, both MLSS concentration and MLVSS digestion efficiency continued to rise, accompanied by a decreasing dissolved oxygen (DO) concentration. More organic matter was released into the supernatant, and sludge microbial flocs tended to reaggregate. The localized anaerobic environment within the FO-MSTD reactor fostered an increase in the relative abundance of bacteria with nitrogen and phosphorus removal functions, thereby positively impacting the mitigation of total nitrogen (TN) and total phosphorus (TP) concentrations in the sludge supernatant. The results of this research enhance comprehension of the advanced FO-MSTD technology in the treatment of WAS.


Assuntos
Fósforo , Esgotos , Esgotos/química , Osmose , Fósforo/metabolismo , Nitrogênio , Digestão , Reatores Biológicos , Eliminação de Resíduos Líquidos/métodos
4.
J Am Chem Soc ; 146(9): 6231-6239, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38386884

RESUMO

Acquiring a deep insight into the electron transfer mechanism and applications of one-dimensional (1D) van der Waals heterostructures (vdWHs) has always been a significant challenge. Herein, through direct observation using aberration-corrected transmission electron microscopy (AC-TEM), we verify the stable formation of a high-quality 1D heterostructure composed of PbI2@single-walled carbon nanotubes (SWCNTs). The phenomenon of electron transfer between PbI2 and SWCNT is elucidated through spectroscopic investigations, including Raman and X-ray photoelectron spectroscopy (XPS). Electrochemical testing indicates the electron transfer and enduring stability of 1D PbI2 within SWCNTs. Moreover, leveraging the aforementioned electron transfer mechanism, we engineer self-powered photodetectors that exhibit exceptional photocurrent and a 3-order-of-magnitude switching ratio. Subsequently, we reveal its unique electron transfer behavior using Kelvin probe force microscopic (KPFM) tests. According to KPFM, the average surface potential of SWCNTs decreases by 80.6 mV after filling. Theoretical calculations illustrate a charge transfer of 0.02 e per unit cell. This work provides an effective strategy for the in-depth investigation and application of electron transfer in 1D vdWHs.

5.
ACS Appl Mater Interfaces ; 16(1): 1317-1325, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38118048

RESUMO

Piezoelectric nanogenerators (PENGs) with molybdenum disulfide (MoS2) monolayers have been intensively studied owing to their superior mechanical durability and stability. However, the limited output performance resulting from a small active area and low strain levels continues to pose a significant challenge that should be overcome. Herein, we report a novel strategy for the epoch-making output performance of a PENG with a MoS2 monolayer by adopting the additive strain concentration concept. The simulation study indicates that strain in the MoS2 monolayer can be initially augmented by the wavy structure resulting from the prestretched poly(dimethylsiloxane) (PDMS) and is further increased through flexural deformation (i.e., bending). Based on these studies, we have developed concentrated strain-applied PENGs with MoS2 monolayers. The wavy structures effectively applied strain to the MoS2 monolayer and generated a piezoelectric output voltage and current of around 580 mV and 47.5 nA, respectively. Our innovative approach to enhancing the performance of PENGs with MoS2 monolayers through the artificial dual strain concept has led to groundbreaking results, achieving the highest recorded output voltage and current for PENGs based on two-dimensional (2D) materials, which provides unique opportunities for the 2D-based energy harvesting field and structural insight into how to improve the net strain on 2D materials.

6.
Heliyon ; 9(12): e22858, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38125524

RESUMO

Background: The benefits and risks of adjuvant-associated COVID-19 vaccines (ACVs) are unclear. The study aimed to assess the immunogenicity and safety of ACVs compared with controls (placebo or the same vaccine without adjuvants [NACVs]). Methods: Randomized controlled trials sourced from PubMed, EMBASE, Web of Science, and Cochrane Library were systematically reviewed. Evaluators extracted information independently. The evidence quality was assessed using random-effects models. The risk of bias was assessed using the Cochrane Risk of Bias tool. Results: Of the 33 studies, 27 analyzed immunogenicity (n = 9069, ACVs group; n = 3757, control), and 26 analyzed safety (n = 58669, ACVs groups; n = 30733 control). Compared with controls, full vaccination with ACVs produced significant immune responses (relative risk [RR] of seroneutralization reaction, 12.3; 95 % confidence interval [95 % CI], 6.92-21.89; standardized mean deviation of geometric mean titer 3.96, 95 % CI, 3.35-4.58). Additionally, ACVs produced significant immunoreactivity compared with NACVs only (P < 0.05). Furthermore, full vaccination with ACVs significantly increased the risk of local and systemic adverse reactions (AEs) compared with controls. However, vaccination with ACVs did not significantly increase the risk of systemic and localized AEs compared with vaccination with NACVs only (P > 0.05). It was observed that ACVs had a lower risk of all-cause mortality than controls (RR, 0.51; 95 % CI 0.30-0.87). It was further found that ACVs produced nAb response against all sublines of the Omicron variant, but the antibody titers were lower than those for the SARS-CoV-2 original strain. Conclusions: The findings of this meta-analysis demonstrate that ACVs may have a superior effect and an acceptable safety in preventing COVID-19. Although these results suggest the potential of ACVs, further studies are required.

7.
J Am Chem Soc ; 145(44): 24349-24357, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37883799

RESUMO

Understanding the interplay between the surface structure and the passivation materials and their effects associated with surface structure modification is of fundamental importance; however, it remains an unsolved problem in the perovskite passivation field. Here, we report a surface passivation principle for efficient perovskite solar cells via a facet-dependent passivation phenomenon. The passivation process selectively occurs on facets, which is observed with various post-treatment materials with different functionality, and the atomic arrangements of the facets determine the alignments of the passivation layers. The profound understanding of facet-dependent passivation leads to the finding of 2-amidinopyridine hydroiodide as the material for a uniform and effective passivation on both (100) and (111) facets. Consequently, we achieved perovskite solar cells with an efficiency of 25.10% and enhanced stability. The concept of facet-dependent passivation can provide an important clue on unidentified passivation principles for perovskite materials and a novel means to enhance the performance and stability of perovskite-based devices.

8.
Water Res ; 245: 120595, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37708772

RESUMO

In order to meet the demand of municipal wastewater for low-carbon treatment and resource recovery, a novel process of anaerobic acidification membrane bioreactor (AAMBR) assisted with a two-stage forward osmosis (FO) (FO-AAMBR-FO) was developed for simultaneously recovering organic matter and nutrients from municipal wastewater. The results indicated that the first FO process concentrated the municipal wastewater to one tenth of the initial volume. The corresponding chemical oxygen demand (COD), ammonia nitrogen (NH4+-N) and total phosphorus (TP) concentration reached up to 2800, 200 and 33 mg/L, respectively. Subsequently, the AAMBR was operated at pH value of 10 for treating the concentration of municipal wastewater, in which the organic matter was successfully converted to acetic acid and propionic acid with a total volatile fatty acids (VFAs) concentration of 1787 mg COD/L and a VFAs production efficiency of 62.36 % during 47 days of stable operation. After that, the NH4+-N and TP concentration in the effluent of the AAMBR were further concentrated to 175 and 36.7 mg/L, respectively, by the second FO process. The struvite was successfully recovered with NH4+-N and TP recovery rate of 94.53 % and 98.59 %, respectively. Correspondingly, the VFAs, NH4+-N and TP concentrations in the residual solution were 2905 mg COD/L, 11.8 and 7.92 mg/L, respectively, which could be used as the raw material for the synthesis of polyhydroxyalkanoate (PHA). Results reported here demonstrated that the FO-AAMBR-FO is a promising wastewater treatment technology for simultaneous recovery of organic matter (in form of VFAs) and nutrients (in form of struvite).


Assuntos
Águas Residuárias , Purificação da Água , Anaerobiose , Fósforo , Nitrogênio , Estruvita , Osmose , Reatores Biológicos , Ácidos Graxos Voláteis , Concentração de Íons de Hidrogênio , Membranas Artificiais , Purificação da Água/métodos
9.
Molecules ; 28(14)2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37513488

RESUMO

A catalyst-free aza-Michael addition/C(sp3)-O bond formation tandem reaction of substituted amino ferrocenes with quinone esters was developed, which provided a green and efficient strategy for the construction of a C(sp3)-O bond from C(sp3)-H, and a series of N-ferrocene-substituted benzodihydrooxazoles were smoothly produced in moderate to excellent yields (up to >99% yield). The mechanism experiments showed that quinone esters performed as both substrate and oxidant. The salient features of this transformation include good functional group tolerance, broad substrate scope and mild conditions.

10.
Immunobiology ; 228(5): 152708, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37523793

RESUMO

The role of programmed cell death 1 (PD1) in cancer immune evasion is of considerable importance, prompting the development of monoclonal antibodies that specifically target PD-1 to enhance the immune system for cancer therapy. Nevertheless, the efficacy of PD1/programmed cell death-Ligand 1 (PD-L1) blocking antibodies is limited to certain patients or tumor types. Although researchers have demonstrated the influence of PD-1 on the positive selection of T cells, its effect on the T-cell repertoire remains uncertain. Lymphoid enhancer binding factor 1 (LEF1) has been known to play a critical role as a transcription factor in the development and maturation of T cells. Despite the greater focus on the study of its homologous protein, T cell factor 1 (TCF1), we discovered that LEF1 had a positive regulatory effect on the transcription of PD1 in mature T cells, including CD4+ T cells, CD8+ T cells, and Treg cells. This finding was observed in LEF1 knockout and LEF1-stimulated mice models. Additionally, we confirmed the direct regulation of PD1 by LEF1 in tumor-infiltrating lymphocytes through tumor-implantation experiments. The direct regulation of PD1 by LEF1 was further validated in the LEF1 knockout cell line. The results of our study provide novel perspectives on the regulation of PD1 in immune responses and investigate potential approaches for clinical anti-PD1 therapy.


Assuntos
Neoplasias , Receptor de Morte Celular Programada 1 , Animais , Camundongos , Antígeno B7-H1/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos , Fator 1 de Ligação ao Facilitador Linfoide/genética , Fator 1 de Ligação ao Facilitador Linfoide/metabolismo , Neoplasias/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , Humanos
11.
Ther Adv Reprod Health ; 17: 26334941231188656, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37497119

RESUMO

Many factors associated with assisted reproductive technologies significantly influence the success of pregnancy after in vitro fertilization (IVF) either directly or indirectly. These factors include sperm processing techniques, egg retrieval, intrauterine artificial insemination, intracytoplasmic sperm injection, and embryo transfer. Among these technologies, sperm quality is one of the most critical factors for a successful IVF pregnancy. The method used for sperm processing plays a crucial role in determining the quality of sperm. Several widely used sorting techniques, such as conventional swim-up, density gradient centrifugation, magnetic activated cell sorting, and hyaluronic acid, have been extensively compared in various studies. Previous studies have shown that each sperm processing method causes varying degrees of sperm damage, particularly in sperm motility, concentration, morphological features, viability, and DNA integrity. However, sperm processing techniques have been developed slowly, and the impact of these methods on pregnancy rates is still unclear. Further exploration is needed. In this review, we aim to compare the results of different sperm processing techniques concerning sperm quality and IVF pregnancy rates. We will also discuss possible clinical approaches, such as microfluidics and integrated approaches, for testing and improving sperm quality.

12.
Mol Neurobiol ; 60(10): 5655-5671, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37335462

RESUMO

Paired immunoglobulin-like receptor B (PirB) was identified as a myelin-associated inhibitory protein (MAIP) receptor that plays a critical role in axonal regeneration, synaptic plasticity and neuronal survival after stroke. In our previous study, a transactivator of transcription-PirB extracellular peptide (TAT-PEP) was generated that can block the interactions between MAIs and PirB. We found that TAT-PEP treatment improved axonal regeneration, CST projection and long-term neurobehavioural recovery after stroke through its effects on PirB-mediated downstream signalling. However, the effect of TAT-PEP on the recovery of cognitive function and the survival of neurons also needs to be investigated. In this study, we investigated whether pirb RNAi could alleviate neuronal injury by inhibiting the expression of PirB following exposure to oxygen-glucose deprivation (OGD) in vitro. In addition, TAT-PEP treatment attenuated the volume of the brain infarct and promoted the recovery of neurobehavioural function and cognitive function. This study also found that TAT-PEP exerts neuroprotection by reducing neuronal degeneration and apoptosis after ischemia-reperfusion injury. In addition, TAT-PEP improved neuron survival and reduced lactate dehydrogenase (LDH) release in vitro. Results also showed that TAT-PEP reduced malondialdehyde (MDA) levels, increased superoxide dismutase (SOD) activity and reduced reactive oxygen species (ROS) accumulation in OGD-injured neurons. The possible mechanism was that TAT-PEP could contribute to the damage of neuronal mitochondria and affect the expression of cleaved caspase 3, Bax and Bcl-2. Our results suggest that PirB overexpression in neurons after ischaemic-reperfusion injury induces neuronal mitochondrial damage, oxidative stress and apoptosis. This study also suggests that TAT-PEP may be a potent neuroprotectant with therapeutic potential for stroke by reducing neuronal oxidative stress, mitochondrial damage, degeneration and apoptosis in ischemic stroke.


Assuntos
Isquemia Encefálica , Disfunção Cognitiva , Traumatismo por Reperfusão , Acidente Vascular Cerebral , Humanos , Transativadores/metabolismo , Neurônios/metabolismo , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/metabolismo , Peptídeos/farmacologia , Oxigênio/metabolismo , Proteínas da Mielina/metabolismo , Apoptose , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/metabolismo , Traumatismo por Reperfusão/complicações , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/metabolismo , Isquemia Encefálica/complicações , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo
13.
Eur J Pharmacol ; 947: 175667, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36997050

RESUMO

Post-stroke anxiety (PSA) is a kind of affective disorder occurring after a stroke, with anxiety as the primary clinical manifestation. PSA's mechanism is unclear, and there are few prevention and treatment measures. Our previous study found that HDAC3 could activate NF-κB signaling through mediated p65 deacetylation, which further influenced microglia activation. That implies HDAC3 may be the key mediator in ischemic stroke mice and modulates anxiety susceptibility to stress. This study established a PSA model in male C57BL/6 mice through photothrombotic stroke combined with chronic restrain stress. We focused on exploring whether esketamine administration can alleviate anxiety-like behavior and neuroinflammation, which may be associated with inhibiting HDAC3 expression and NF-κB pathway activation. The results showed that esketamine administration alleviated anxiety-like behavior in PSA mice. And the results showed that esketamine alleviated cortical microglial activation, altered microglial number, and kept morphology features. Furthermore, the results showed that the expression of HDAC3, phosphor-p65/p65, and COX1 significantly decreased in esketamine-treated PSA mice. Besides, we also found that esketamine reduced PGE2 expression, one of the primary regulators of negative emotions. Interestingly, our results indicate that esketamine reduced the perineuronal net (PNN) number in the pathological process of PSA. In conclusion, this study suggests esketamine could alleviate microglial activation, reduces inflammatory cytokine, and inhibits the expression of HDAC3 and NF-κB in the cortex of PSA mice to attenuate anxiety-like behavior. Our results provided a new potential therapeutic target for applying esketamine to PSA.


Assuntos
NF-kappa B , Acidente Vascular Cerebral , Masculino , Camundongos , Animais , NF-kappa B/metabolismo , Microglia/metabolismo , Camundongos Endogâmicos C57BL , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/metabolismo , Ansiedade/tratamento farmacológico , Ansiedade/etiologia
14.
Biochem Biophys Rep ; 34: 101457, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36942321

RESUMO

T-cell acute lymphoblastic leukemia (T-ALL) is a type of aggressive hematologic malignancy. It progresses quickly and it is likely to be fatal within a few months without treatment. Despite the limitations of current clinical therapies, there is an urgent need for novel and targeted therapies. To explore potential targeted therapies, molecular genetic mechanisms of T-ALL metastasis must be uncovered. However, the genes and mechanisms that mediate T-ALL metastasis are largely unknown. Recent insights into T-ALL biology have identified several genes that can be grouped into several targetable signaling pathways. The Wnt/ß-catenin signaling pathway is one of the most important pathways. Our work investigated the functions of TCF1 and LEF1 in cell growth and migration mediated by the Wnt signaling pathway. We found that TCF1 and LEF1 knockdown weakly repressed T-ALL cell proliferation but distinctly impaired cell migration. T-ALL metastasis is dependent on cell migration and invasion. Our results displayed that TCF1 and LEF1 regulated T-ALL cell migration by the Wnt-dependent chemokine and cytokine-induced inflammation and cadherin signaling pathways. By transcriptionally regulating these pathways-associated genes, TCF1 and LEF1 inhibited cell adhesion and promoted cell migration and invasion.

15.
J Org Chem ; 88(5): 2841-2850, 2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36812409

RESUMO

We demonstrated here an efficient synthetic method of carbazole derivatives from readily available N-arylnaphthalen-2-amines and quinone esters catalyzed by Brønsted acid. With this strategy, a series of carbazole derivatives were obtained in good to excellent yields (76 to >99) under mild conditions. Large scale reaction illustrated the synthetic utility of this protocol. Meanwhile, a series of C-N axially chiral carbazole derivatives were also constructed in moderate to good yields (36-89% yield) with moderate to excellent atroposelectivities (44-94% ee) by using chiral phosphoric acid as a catalyst, which provides a novel strategy for the atroposelective construction of C-N axially chiral compounds and a new member of the C-N atropisomers.

16.
Adv Sci (Weinh) ; 10(3): e2204801, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36437039

RESUMO

To prevent surgical site infection (SSI), which significantly increases the rate morbidity and mortality, eliminating microorganisms is prominent. Antimicrobial resistance is identified as a global health challenge. This work proposes a new strategy to eliminate microorganisms of deep tissue through electrical stimulation with an ultrasound (US)-driven implantable, biodegradable, and vibrant triboelectric nanogenerator (IBV-TENG). After a programmed lifetime, the IBV-TENG can be eliminated by provoking the on-demand device dissolution by controlling US intensity with no surgical removal of the device from the body. A voltage of ≈4 V and current of ≈22 µA generated from IBV-TENG under ultrasound in vitro, confirming inactivating ≈100% of Staphylococcus aureus and ≈99% of Escherichia coli. Furthermore, ex vivo results show that IBV-TENG implanted under porcine tissue successfully inactivates bacteria. This antibacterial technology is expected to be a countermeasure strategy against SSIs, increasing life expectancy and healthcare quality by preventing microorganisms of deep tissue.


Assuntos
Antibacterianos , Infecções Estafilocócicas , Animais , Suínos , Ultrassonografia , Antibacterianos/uso terapêutico , Estimulação Elétrica , Escherichia coli
17.
Environ Sci Pollut Res Int ; 30(7): 19224-19233, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36227491

RESUMO

In this study, poly(acrylic acid) sodium (PAA-Na) salt was selected as representative polymer additive and the effect on forward osmosis (FO) performance of traditional draw solute NaCl was investigated. Results showed that PAA-Na increased water flux in both FO and PRO mode at 25 °C (up to 50%). Water flux and specific RSF firstly increased and then kept stable with the increasing concentration of PAA-Na additive. However, PAA-Na cannot enhance water permeation effectively at 35 and 45 °C. PAA-Na influenced FO performance by (1) increasing membrane hydrophilicity, which can increase water permeation, and was dominant at low temperature, and (2) causing pore-clogging, leading water flux decline, which was significant at high temperature. Furthermore, the influence of PAA-Na was compared with another polymer PAM and divalent salts MgCl2. The addition of PAM increased water flux slightly (lower than 25%), but increased RSF at the same time, due to the negative charge. Although MgCl2 decreased RSF and kept water flux fixed, its role was not obvious. In all, PAA-Na had advantages to improve FO performance.


Assuntos
Sódio , Purificação da Água , Purificação da Água/métodos , Cloreto de Sódio , Resinas Acrílicas , Água , Osmose , Membranas Artificiais
18.
J Hazard Mater ; 443(Pt A): 130170, 2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36265376

RESUMO

Per-and polyfluoroalkyl substances (PFASs) are omnipresent globally and received increasing attention recently. However, there are limited data on PFASs in the Tibetan Plateau (TP), a remote high-altitude mountain region, which is regard as an important indicator region to study long-range transport behaviors of contaminants. This study investigates the occurrence, distribution, partitioning behavior, and sources of 26 PFASs in water and sediments from the four lakes of TP. The ΣPFAS concentrations ranged from 338 to 9766 pg L-1 in water, and 12.2-414 pg g-1 dry weight in sediments. Perfluorobutanonic acid (PFBA) and perfluorooctane sulfonate (PFOS) were detected in all samples. Qinghai Lake had the highest ΣPFAS concentrations in both water and sediments, while the Ranwu Lake had the lowest. The functional groups and CF2 moiety units were investigated as essential factors influencing the partition behavior. Principal component analysis (PCA) combined back-trajectory was used to infer possible sources of PFASs. The results suggested that the main source of PFASs in Yamdrok Lake, Namco Lake, and Ranwu Lake on southern TP were mainly originated from South Asia via long-range atmospheric transport (LRAT); while for the Qinghai Lake of northern TP, LRAT, local emissions, and tourism activities were the primary sources of PFASs.


Assuntos
Ácidos Alcanossulfônicos , Fluorocarbonos , Poluentes Químicos da Água , Lagos , Fluorocarbonos/análise , Água/análise , Sedimentos Geológicos , Monitoramento Ambiental/métodos , Tibet , Poluentes Químicos da Água/análise , Ácidos Alcanossulfônicos/análise , China
19.
Cell Biosci ; 12(1): 83, 2022 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-35659740

RESUMO

Transcription factors directly regulate gene expression by recognizing and binding to specific DNA sequences, involving the dynamic alterations of chromatin structure and the formation of a complex with different kinds of cofactors, like DNA/histone modifying-enzymes, chromatin remodeling factors, and cell cycle factors. Despite the significance of transcription factors, it remains unclear to determine how these cofactors are regulated to cooperate with transcription factors, especially DNA/histone modifying-enzymes. It has been known that DNA/histone modifying-enzymes are regulated by post-translational modifications. And the most common and important modification is phosphorylation. Even though various DNA/histone modifying-enzymes have been classified and partly explained how phosphorylated sites of these enzymes function characteristically in recent studies. It still needs to find out the relationship between phosphorylation of these enzymes and the diseases-associated transcriptional regulation. Here this review describes how phosphorylation affects the transcription activity of these enzymes and other functions, including protein stability, subcellular localization, binding to chromatin, and interaction with other proteins.

20.
Chem Sci ; 13(13): 3796-3802, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-35432891

RESUMO

Chiral α-amino ketones are common structural motifs in natural products and pharmaceuticals, as well as important synthons in organic synthesis. Thus, establishing efficient methods for preparing compounds with these privileged scaffolds is an important endeavor in synthetic chemistry. Herein we disclose a new catalytic asymmetric approach for the synthesis of chiral α-amino ketones through a chiral palladium-catalyzed arylation reaction of in situ generated challenging α-keto imines from previously unreported C-acyl N-sulfonyl-N,O-aminals, with arylboronic acids. The current reaction offers a straightforward approach to the asymmetric synthesis of acyclic α-amino ketones in a practical and highly stereocontrolled manner. Meanwhile, the multiple roles of the chiral Pd(ii) complex catalyst in the reaction were also reported.

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