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This work established a quantitative method to access the shear stability of aerobic granular sludge (AGS) and validated its feasibility by using the mature AGS from a pilot-scale (50 tons/day) membrane bioreactor (MBR) for treating real municipal wastewater. The results showed that the changing rate (ΔS) of the peak area (S) of granule size distribution (GSD) exhibited an exponential relationship (R2≥0.76) with the shear time (y=a-b·cx), which was a suitable indicative index to reflect the shear stability of different AGS samples. The limiting granule size (LGS) was defined and proposed to characterize the equilibrium size for AGS after being sheared for a period of time, whose value in terms of Dv50 showed high correlation (R2=0.92) with the parameter a. The free Ca2+ (28.44-34.21 mg/L) in the influent specifically interacted with polysaccharides (PS) in the granule's extracellular polymeric substance (EPS) as a nucleation site, thereby inducing the formation of Ca precipitation to enhance its Young's modulus, while Ca2+ primarily interacted with PS in soluble metabolic product (SMP) during the initial granulation process. Furthermore, the Young's modulus significantly affected the parameter a related to shear stability (R2=0.99). Since the parameter a was more closely related (R2=1.00) to ΔS than that of the parameter b or c, the excellent correlation (R2=0.99) between the parameter a and the wet density further verified the feasibility of this method.
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Reactores Biológicos , Aguas del Alcantarillado , Eliminación de Residuos Líquidos , Eliminación de Residuos Líquidos/métodos , Proyectos Piloto , Aguas Residuales/química , Membranas Artificiales , AerobiosisRESUMEN
Purpose: To describe the use of an amniotic membrane graft (AMG) with fibrin sealant to address an overfiltering trabeculectomy flap encountered intraoperatively. Observations: A 35-year-old female with severe primary open angle glaucoma underwent trabeculectomy with mitomycin C due to uncontrolled intraocular pressure (IOP). Intraoperatively, the elastic nature of the scleral flap led to overfiltration, causing persistent anterior chamber shallowing despite numerous sutures. To decrease but not completely shut down aqueous outflow through the trabeculectomy flap, we utilized AMG and fibrin sealant to stabilize the flap. Postoperatively, the patient had a formed anterior chamber, elevated bleb and significantly reduced IOP, without the need for additional glaucoma medications. Conclusions and importance: Amniotic membrane grafts (AMG) with fibrin sealant may help regulate aqueous flow efflux, maintain anterior chamber stability, and mitigate the risk of postoperative hypotony in trabeculectomy surgery. AMG was chosen in this setting given its anti-inflammatory, anti-fibrotic properties, as well as its optically clear nature to allow for post-operative visualization of the flap. AMG allows for early postoperative stabilization of the scleral flap without complete obstruction, and may be useful in patients at risk of early postoperative hypotony.
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OBJECTIVE: Carotenoids are lipophilic plant molecules with antioxidant properties. Some carotenoids such as ß-carotene also serve as vitamin A precursors, playing a key role in human health. Carotenoids are transported in lipoproteins with other lipids such as cholesterol, however, the mechanisms responsible for carotenoid storage in tissues and their non-enzymatic elimination remain relatively unexplored. The goal of this study was to examine the contribution of the low-density lipoprotein receptor (LDLR) in the bodily distribution and disposal of carotenoids. METHODS: We employed mice lacking one or both carotenoid-cleaving enzymes as suitable models for carotenoid accumulation. We examined the contribution of LDLR in carotenoid distribution by crossbreeding these mice with Ldlr-/- mice or overexpressing LDLR in the liver. RESULTS: Our results show that LDLR plays a dual role in carotenoid homeostasis by simultaneously favoring carotenoid storage in the liver and adipose tissue while facilitating their fecal elimination. CONCLUSIONS: Our results highlight a novel role of the LDLR in carotenoid homeostasis, and unveil a previously unrecognized disposal pathway for these important bioactive molecules.
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As the potential adverse health and environmental effects of nanoscale pollutants have garnered significant attention, the demand for monitoring and capturing ultrafine particulate matter has been growing. With the rise in ultrafine dust emissions, this issue has become increasingly important. However, submicron particles require advanced strategies to be captured because of their limited inertial effect. For example, electrostatic air filters have been investigated for their improved performance in the fine particle regime. On the other hand, Raman spectroscopy was proposed as a promising analytical strategy for aerosol particles because it can be used to conveniently detect analytes in a label-free manner. Thus, the synergistic integration of these strategies can open new applications for addressing environment-related challenges. This study presents a multifunctional approach for achieving both air filtration and surface-enhanced Raman scattering (SERS) for analyte identification. We propose a nanoporous membrane composed of a thin gold layer, copper, and copper oxide to provide the desired functions. The structures are produced by performing scalable electrodeposition and subsequent electron-beam evaporation, attaining an excellent filtration efficiency of 95.9% with an applied voltage of 5 kV for 300 nm KCl particles and a pressure drop of 121 Pa. Raman intensity measurements confirm that the nanodendritic surface of the membrane intensifies the Raman signals and allows for the detection of 10 µL of nanoplastic particle dispersion with a concentration of 50 µg/mL. Rhodamine 6G aerosol stream with an approximate particle deposition rate of 0.040 × 106 mm-2·min-1 is also identified in a minimum detectable time of 50 s. The membrane is shown to be recyclable owing to its structural robustness in organic solvents. In addition, the fatigue resistance of the structure is evaluated through 22,000 iterative loading cycles at a pressure of 177 kPa. No performance degradation is observed after the fatigue loading.
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Membrane filtration is a mainstream method for landfill leachate treatment, leaving the landfill leachate membrane concentrates (LLMCs) a high-toxicity residue. Conventional LLMCs disposal technology shows specific challenges due to the low biodegradability, high inorganic salts, and high heavy metal ions content of LLMCs. Therefore, it is necessary to degrade LLMCs with a more suitable technology. In this study, a special method was proposed to convert some organic chemicals into valuable compounds by aqueous phase reforming (APR). Ni-based catalysts (Ni//La2O3, Ni/CeO2, Ni/MgO, and Ni/Al2O3) were prepared to investigate the effect of different supports on the APR of LLMCs. APR performed outstanding characteristics in the decrease of chemical oxygen demand (COD) and total organic carbon (TOC), the degradation of macromolecules, and the removal of heavy metal ions in the aqueous phase. In addition, H2 was generated which is beneficial for energy compensating during the APR process. The best-performing catalyst (Ni/Al2O3) was selected to investigate the effects of reaction temperature, reaction time, and catalyst addition on product distribution. The optimal H2 selectivity (44.71%) and H2 production (11.63 mmol/g COD) were obtained at 250 °C with 2 g Ni/Al2O3 usage for 1 h. This paper provided a new perspective on the disposal of LLMCs, which will degrade pollutants efficiently.
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Biogenic synthesis of nanoparticles has been established as an environmentally benign and sustainable approach. This study emphasizes biosynthesis of selenium nanoparticles (SeNPs) utilizing leaf extract of Nyctanthes arbor-tritis L., well known for its abundant bioactive compounds. Various analytical techniques were employed for characterization of synthesized SeNPs. X-ray diffraction (XRD) spectroscopy confirmed the crystalline structure and revealed the average crystalline size of SeNPs to be 44.57 nm. Additionally, UV-Vis spectroscopy confirmed successful synthesis of SeNPs by validating the surface plasmon resonance (SPR) properties of SeNPs. FTIR analysis data revealed different bonds and their corresponding functional groups responsible for the synthesis and stability of synthesized SeNPs. DLS and zeta analysis revealed that 116.5 nm sized SeNPs were stable in nature. Furthermore, field emission scanning electron microscopy (FE-SEM) validated the spherical morphology of SeNPs with a size range of 60-80 nm. Inductively coupled plasma-optical emission spectroscopy (ICP-OES) determined the concentration of SeNPs in the obtained colloidal solution. Antioxidant activity of synthesized SeNPs was evaluated employing DPPH and H2O2 assay, revealed that the synthesized SeNPs were effective antioxidant agent. Additionally, antimicrobial potential was evaluated against a panel of Gram-positive and Gram-negative bacteria and found to be effective at higher concentration of SeNPs. SeNPs also exhibited strong anti-biofilm activity while evaluated against various biofilm producing bacteria like Escherichia coli , Staphylococcus epidermidis and Klebsiella pneumonia. The cytotoxicity of the bio-synthesized SeNPs was evaluated against HEK 293 cell line, exhibited minimal toxicity even at concentration 100 µg/mL with 65% viable cells. SeNPs has also been evaluated for dye degradation which has indicated excellent photocatalytic activity of synthesized SeNPs. The experimental data obtained altogether demonstrated that synthesized SeNPs exhibited significant antimicrobial and anti-biofilm activity against various pathogens, and also showed significant antioxidant and photocatalytic efficiency.
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Background: Drought is the most significant factor limiting maize production, given that maize is a crop with a high water demand. Therefore, studies investigating the mechanisms underlying the drought tolerance of maize are of great importance. There are no studies comparing drought tolerance among economically important subspecies of maize. This study aimed to reveal the differences between the physio-biochemical, enzymatic, and molecular mechanisms of drought tolerance in dent (Zea mays indentata), popcorn (Zea mays everta), and sugar (Zea mays saccharata) maize under control (no-stress), moderate, and severe drought stress. Methods: Three distinct irrigation regimes were employed to assess the impact of varying levels of drought stress on maize plants at the V14 growth stage. These included normal irrigation (80% field capacity), moderate drought (50% field capacity), and severe drought (30% field capacity). All plants were grown under controlled conditions. The following parameters were analyzed: leaf relative water content (RWC), loss of turgidity (LOT), proline (PRO) and soluble protein (SPR) contents, membrane durability index (MDI), malondialdehyde (MDA), and hydrogen peroxide (H2O2) content, the antioxidant enzyme activities of superoxide dismutase (SOD), ascorbate peroxidase (APX), and catalase (CAT). Additionally, the expression of heat shock proteins (HSPs) was examined at the transcriptional and translational levels. Results: The effects of severe drought were more pronounced in sugar maize, which had a relatively high loss of RWC and turgor, membrane damage, enzyme activities, and HSP90 gene expression. Dent maize, which is capable of maintaining its RWC and turgor in both moderate and severe droughts, and employs its defense mechanism effectively by maintaining antioxidant enzyme activities at a certain level despite less MDA and H2O2 accumulation, exhibited relatively high drought tolerance. Despite the high levels of MDA and H2O2 in popcorn maize, the up-regulation of antioxidant enzyme activities and HSP70 gene and protein expression indicated that the drought coping mechanism is activated. In particular, the positive correlation of HSP70 with PRO and HSP90 with enzyme activities is a significant result for studies examining the relationships between HSPs and other stress response systems. The discrepancies between the transcriptional and translational findings provide an opportunity for more comprehensive investigations into the role of HSPs in stress conditions.
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Sequías , Zea mays , Zea mays/genética , Estrés Fisiológico/genética , Estrés Fisiológico/fisiología , Regulación de la Expresión Génica de las Plantas , Peróxido de Hidrógeno/metabolismo , Hojas de la Planta/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Agua/metabolismo , Especificidad de la Especie , Antioxidantes/metabolismoRESUMEN
Rationale: Alagille syndrome is a rare genetic disorder with dental and facial abnormalities in the head-and-neck area. It is autosomal dominant and occurs in approximately 1 in 100,000 people. No cases of Alagille Syndrome (ALGS) with mandibular hypoplasia and temporomandibular joint ankyloses (TMJa) have been reported to date. Patient Concerns and Diagnosis: A 3-year-old female patient suffering from ALGS came to our hospital affected by unilateral mandibular hypoplasia and TMJa with severe limitation of mouth opening (maximal interincisal distance [MID] of 2 mm). Treatment: A two-phase surgical management approach was undertaken based on computed tomography scans and the patient's age. The first phase involved mandibular distraction, followed by arthroplasty with amniotic human membrane placement. Outcomes: After immediate post-surgery rehabilitation, the patient showed good mandibular function with no complications after 15 months. MID was 20 mm. Take-away Lessons: This is a rare and interesting case with no previous literature reports. The use of amniotic membranes in surgical management adds further significance.
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Lysosomes are more than just cellular recycling bins; they play a crucial role in regulating key cellular functions. Proper lysosomal function is essential for growth pathway regulation, cell proliferation, and metabolic homeostasis. Impaired lysosomal function is associated with lipid storage disorders and neurodegenerative diseases. Lysosomes form extensive and dynamic close contacts with the membranes of other organelles, including the endoplasmic reticulum, mitochondria, peroxisomes, and lipid droplets. These membrane contacts sites (MCSs) are vital for many lysosomal functions. In this chapter, we will explore lysosomal MCSs focusing on the machinery that mediates these contacts, how they are regulated, and their functional implications on physiology and pathology.
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Comunicación Celular , Homeostasis , Lisosomas , Lisosomas/metabolismo , Humanos , Animales , Membranas Intracelulares/metabolismoRESUMEN
Most patients with schizophrenia (SCZ) do not exhibit violent behaviors and are more likely to be victims rather than perpetrators of violent acts. However, a subgroup of forensic detainees with SCZ exhibit tendencies to engage in criminal violations. Although numerous models have been proposed, ranging from substance use, serotonin transporter gene, and cognitive dysfunction, the molecular underpinnings of violence in SCZ patients remains elusive. Lithium and clozapine have established anti-aggression properties and recent studies have linked low cholesterol levels and ultraviolet (UV) radiation with human aggression, while vitamin D3 reduces violent behaviors. A recent study found that vitamin D3, omega-3 fatty acids, magnesium, and zinc lower aggression in forensic population. In this review article, we take a closer look at aryl hydrocarbon receptor (AhR) and the dysfunctional lipidome in neuronal membranes, with emphasis on cholesterol and vitamin D3 depletion, as sources of aggressive behavior. We also discuss modalities to increase the fluidity of neuronal double layer via membrane lipid replacement (MLR) and natural or synthetic compounds.
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Antibiotic resistance (AMR) poses a significant global health challenge, with swine farms recognized as major reservoirs of antibiotic resistance genes (ARGs). Recently, bacterial membrane vesicles (BMVs) have emerged as novel carriers mediating horizontal gene transfer. However, little is known about the ARGs carried by BMVs in swine farm environments and their transfer potential. This study investigated the distribution, sources, and microbiological origins of BMVs in three key microbial habitats of swine farms (feces, soil, and fecal wastewater), along with the ARGs and mobile genetic elements (MGEs) they harbor. Characterization of BMVs revealed particle sizes ranging from 20 to 500 nm and concentrations from 108 to 1012 particles/g, containing DNA and proteins. Metagenomic sequencing identified BMVs predominantly composed of members of the Proteobacteria phyla, including Pseudomonadaceae, Moraxellaceae, and Enterobacteriaceae, carrying diverse functional genes encompassing resistance to 14 common antibiotics and 74,340 virulence genes. Notably, multidrug resistance, tetracycline, and chloramphenicol resistance genes were particularly abundant. Furthermore, BMVs harbored various MGEs, primarily plasmids, and demonstrated the ability to protect their DNA cargo from degradation and facilitate horizontal gene transfer, including the transmission of resistance genes. In conclusion, this study reveals widespread presence of BMVs carrying ARGs and potential virulence genes in swine farm feces, soil, and fecal wastewater. These findings not only provide new insights into the role of extracellular DNA in the environment but also highlight concerns regarding the gene transfer potential mediated by BMVs and associated health risks.
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Morphogenetic regulation during embryogenesis and regeneration rely on information transfer and coordination between different regions. Here, we explore theoretically the coupling between bioelectrical and transcriptional oscillations at the individual cell and multicellular levels. The simulations, based on a set of ion channels and intercellular gap junctions, show that bioelectrical and transcriptional waves can electrophysiologically couple distant regions of a model network in phase and antiphase oscillatory states that include synchronization phenomena. In this way, different multicellular regionalizations can be encoded by cell potentials that oscillate between depolarized and polarized states, thus allowing a spatio-temporal coding. Because the electric potential patterns characteristic of development and regeneration are correlated with the spatial distributions of signaling ions and molecules, bioelectricity can act as a template for slow biochemical signals following a hierarchy of experimental times. In particular, bioelectrical gradients that couple cell potentials to transcription rates give to each single cell a rough idea of its location in the multicellular ensemble, thus controlling local differentiation processes that switch on and off crucial parts of the genome.
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Modelos Biológicos , Transcripción Genética , Fenómenos Electrofisiológicos/fisiología , Canales Iónicos/fisiología , Canales Iónicos/metabolismo , Canales Iónicos/genética , Uniones Comunicantes/fisiología , Animales , Humanos , Simulación por ComputadorRESUMEN
Nimodipine is the primary clinical drug used to treat cerebral vasospasm following subarachnoid hemorrhage. Currently, tablets have low bioavailability when taken orally, and injections contain ethanol. Therefore, we investigated a new method of nimodipine administration, namely, nasoencephalic administration. Nasal administration of nimodipine was carried out by attaching the cell-penetrating peptide octa-arginine (R8) to liposomes of nimodipine and incorporating it into a temperature-sensitive in situ gel. The prepared liposomes and gels underwent separate evaluations for in vitro characterization. In vitro release exhibited a significant slow-release effect. In vitro toad maxillary cilia model, RPMI 2650 cytotoxicity, and in vivo SD rat pathological histotoxicity experiments showed that all the dosage from the groups had no significant toxicity to toad maxillary cilia, RPMI 2650 cells, and SD rat tissues and organs, and the cilia continued to oscillate up to 694 ± 10.15 min, with the survival rate of the cells being above 85%. A transwell nasal mucosa cell model and an isolated porcine nasal mucosa model were established, and the results showed that the osmolality of the R8-modified nimodipine liposomal gel to nasal mucosal cells and isolated porcine nasal mucosa was 30.41 ± 2.14 and 65.9 ± 7.34 µg/mL, respectively, which was significantly higher than that of the NM-Solution and PEGylated nimodipine liposome gel groups. Animal fluorescence imaging studies revealed that the R8-modified nimodipine liposomal gel displayed increased brain fluorescence intensity compared to the normal liposomal gel. Pharmacokinetic results showed that after transnasal administration, the AUC(0-∞) of the R8-modified nimodipine liposomal gel was 11.662 ± 1.97 µg·mL-1, which was significantly higher than that of the plain nimodipine liposomal gel (5.499 ± 2.89 µg·mL-1). Brain-targeting experiments showed that the brain-targeting efficiencies of the PEGylated nimodipine liposome gel and R8-modified PEGylated nimodipine liposome gels were 20.44 and 33.45, respectively, suggesting that R8/PEG/Lip-NM-TSG significantly increased the brain-targeting of the drug.
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Platinum group metal (PGM)-free electrocatalysts have emerged as promising alternatives to replace Pt for the oxygen reduction reaction (ORR) in anion exchange membrane fuel cells (AEMFCs). However, traditional synthesis methods limit the single-atom site density due to metal agglomeration at higher temperatures. This work explores the preparation of hierarchically porous atomically dispersed electrocatalysts for the ORR. The materials were prepared via ionothermal synthesis, where magnesium nitrate was used to prepare hierarchically porous carbon materials. The in-situ formed Mg-Nx sites were trans-metalated to yield ORR-active Fe-Nx sites. The resulting carbon-based catalysts displayed excellent electrocatalytic activity, attributed to the atomically dispersed Fe-Nx active sites and high meso- and macroporosity that enhances the mass transport and exposes more accessible active sites.
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The red microalga Galdieria sulphuraria has emerged as a promising biotechnological platform for large-scale cultivation and production of high-value compounds, such as the blue pigment phycocyanin. However, a large amount of freshwater and a substantial supply of nutrients challenge both the environmental and the economic sustainability of algal cultivation. Additionally, the extremophilic nature of Galdieria sulphuraria requires cultivation in an acidic culture medium that directly leads to strongly acidic wastewater, which in turn generally exceeds legal limits for industrial wastewater discharge. This research aims to address these challenges, by investigating cultivation water reuse as a strategy to reduce the impacts of Galdieria sulphuraria management. The results indicated that a 25 % water reuse may be easily implemented and showed to be effective at the pilot scale, providing no significant changes in microalgae growth (biomass productivity ~0.21 g L-1 d-1) or in phycocyanin accumulation (~ 10.8 % w/w) after three consecutive cultivation cycles in reused water. Moreover, a single cultivation cycle with water reuse percentages of 71 and 98 %, achieved with membrane filtration and with centrifugation, respectively, was also successful (biomass productivity ~0.24 g L-1 d-1). These findings encourage freshwater reuse implementations in the microalgae sector and support further investigations focusing on coupling cultivation and harvesting in continuous, real-scale configurations. Centrifugation and membrane filtration required substantially different specific electrical energy consumption for water reuse and biomass concentration: in real applications, the former technique would roughly span from 1 to 10 kWh m-3 while the latter is expected to fall within the ample range 0.1-100 kWh m-3, strongly dependent on system size. For this reason, the most suitable separation train should be chosen on a case-by-case basis, considering the prevailing flow rate and the target biomass concentration factor targeted by the separation process.
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Microalgas , Microalgas/crecimiento & desarrollo , Rhodophyta/crecimiento & desarrollo , Aguas Residuales , Eliminación de Residuos Líquidos/métodos , BiomasaRESUMEN
Cyclopropane fatty acid synthases (CFAS) catalyze the conversion of unsaturated fatty acids to cyclopropane fatty acids (CFAs) within bacterial membranes. This modification alters the biophysical properties of membranes and has been correlated with virulence in several human pathogens. Despite the central role played by CFAS enzymes in regulating bacterial stress responses, the mechanistic properties of the CFAS enzyme family and the consequences of CFA biosynthesis remain largely uncharacterized in most bacteria. We report the first characterization of the CFAS enzyme from Pseudomonas aeruginosa (PA), an opportunistic human pathogen with complex membrane biology that is frequently associated with antimicrobial resistance and high tolerance to various external stressors. We demonstrate that CFAs are produced by a single enzyme in PA and that cfas gene expression is upregulated during the transition to stationary phase and in response to oxidative stress. Analysis of PA lipid extracts reveal a massive increase in CFA production as PA cells enter stationary phase and help define the optimal membrane composition for in vitro assays. The purified PA-CFAS enzyme forms a stable homodimer and preferentially modifies phosphatidylglycerol lipid substrates and membranes with a higher content of unsaturated acyl chains. Bioinformatic analysis across bacterial phyla shows highly divergent amino acid sequences within the lipid-binding domain of CFAS enzymes, perhaps suggesting distinct membrane-binding properties among different orthologs. This work lays an important foundation for further characterization of CFAS in P. aeruginosa and for examining the functional differences between CFAS enzymes from different bacteria.
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Membrane-contamination during electrodialysis (ED) process is still a non-negligible challenge, while irreversible consumption and unsustainability have become the main bottlenecks limiting the improvement of anion exchange membranes (AEMs) anti-contamination activity. Here, we introduce a novel approach to design AEMs by chemically assembling 4-pyndinepropanol with bromomethylated poly(2,6-dimethyl-1,4-phenylene oxide) (BPPO) in an electrochromic-inspired process. Subsequently, the co-mingled TiO2@Ag nanosheet with the casting-solution were sprayed onto the surface of the substrate membrane to create a micrometer-thick interfacial layer. The addition of Ag nanoparticles (NPs) enhances the active sites of TiO2, resulting in stronger local surface plasmon resonance (LSPR) effects and reducing its energy band gap limitation (From 3.11 to 2.63 eV). Post-electrodialysis electrochromic AEMs incorporating TiO2@Ag exhibit synergistic enhancement of sunlight absorption, effectively suppressing photogenerated carrier binding and promoting migration. These resultant-membranes demonstrate significantly improved bacterial inhibition properties (42.0-fold increase for E. coli) and degradation activity (7.59-fold increase for rhodamine B) compared to pure TiO2 membranes. Importantly, they maintain photocatalytic activity without compromising salt-separation performance or stability, as the spraying process utilizes the same substrate materials. This approach to rational design and regulation of anti-contamination AEMs offers new insights into the collaborative synergy of color-changing and photocatalytic materials.
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Membranas Artificiales , Plata , Titanio , Titanio/química , Plata/química , Catálisis , Luz , Escherichia coli/efectos de los fármacos , Diálisis , Aniones , Nanopartículas del Metal/químicaRESUMEN
Chloroplast-encoded multi-span thylakoid membrane proteins are crucial for photosynthetic complexes, yet the coordination of their biogenesis remains poorly understood. To identify factors that specifically support the cotranslational biogenesis of the reaction center protein D1 of photosystem (PS) II, we generated and affinity-purified stalled ribosome-nascent chain complexes (RNCs) bearing D1 nascent chains. Stalled RNCs translating the soluble ribosomal subunit uS2c were used for comparison. Quantitative tandem-mass spectrometry of the purified RNCs identified around 140 proteins specifically associated with D1 RNCs, mainly involved in protein and cofactor biogenesis, including chlorophyll biosynthesis, and other metabolic pathways. Functional analysis of STIC2, a newly identified D1 RNC interactor, revealed its cooperation with chloroplast protein SRP54 in the de novo biogenesis and repair of D1, and potentially other cotranslationally-targeted reaction center subunits of PSII and PSI. The primary binding interface between STIC2 and the thylakoid insertase Alb3 and its homolog Alb4 was mapped to STIC2's ß-sheet region, and the conserved Motif III in the C-terminal regions of Alb3/4.
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Organic pollutants, such as toluene and xylene, in industrial wastewater negatively impact the environment. Membrane treatment is one of the best methods to reduce impurities in wastewater. Existing membranes that coat the water surface with hydrophilic material only effectively resist the initial fouling, resulting in poor oil and water selectivity. Here we report a simple and efficient method to enhance the water flux and antifouling properties of polyvinylidene fluoride (PVDF) membranes. This method involves developing and applying Catechol-Fe(III) complexes with a rough surface to the PVDF surface. Forming Catechol-Fe(III) complexes on the surface better anchors them to the membrane than the dip-coating method. The PVDF membranes with rough Catechol-Fe(III) complexes are superoleophobic, with an oil contact angle of 152 ° and high permeability, with pure water flux of 10487 Lm-2h-1bar-1 and 1 wt% toluene in water emulsion flux of 4697 Lm-2h-1bar-1. Overall, the straightforward manufacturing process, increased permeability, and outstanding antifouling capabilities of the PVDF membrane incorporating rough nanoparticles offer promising prospects for designing and implementing suitable membranes for oil in water emulsion separation applications.
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BACKGROUND: Perioperative heparin-free anticoagulation extracorporeal membrane oxygenation (ECMO) for lung transplantation is rarely reported. OBJECTIVE: To evaluate the impact of a heparin-free strategy on bleeding and thrombotic events, blood transfusion, and coagulation function during the early perioperative period and on prognosis, and to observe its effect on different ECMO types. DESIGN: A retrospective cohort study. METHODS: Data were collected from 324 lung transplantation patients undergoing early perioperative heparin-free ECMO between August 2017 and July 2022. Clinical data including perioperative bleeding and thrombotic events, blood product transfusion, coagulation indicators and 1-year survival were analysed. RESULTS: Patients were divided in venovenous (VV; n = 251), venoarterial (VA; n = 40) and venovenous-arterial (VV-A; n = 33) groups. The VV group had the lowest intraoperative bleeding and thoracic drainage within 24 h postoperatively. Vein thrombosis occurred in 30.2% of patients within 10 days postoperatively or 1 week after ECMO withdrawal, and no significant difference was found among the three groups. Double lung transplantation, increased intraoperative bleeding, and increased postoperative drainage were associated with vein thrombosis. Except for acute myocardial infarction in one patient, no other serious thrombotic events occurred. The VV-ECMO group had the lowest demand for blood transfusion. The highest prothrombin time and the lowest fibrinogen levels were observed in the VA group during ECMO run, while the highest platelet counts were found in the VV group. Both intraoperative bleeding and thoracic drainage within 24 h postoperatively were independent predictors for 1-year survival, and no thrombosis-related deaths occurred. CONCLUSION: Short-term heparin-free anticoagulation, particularly VV-ECMO, did not result in serious thrombotic events or thrombosis-related deaths, indicating that it is a safe and feasible strategy for perioperative ECMO in lung transplantation.