Fast, strong, and reversible adhesives with dynamic covalent bonds for potential use in wound dressing.

Adhesives typically fall into two categories: those that have high but irreversible adhesion strength due to the formation of covalent bonds at the interface and are slow to deploy, and others that are fast to deploy and the adhesion is reversible but weak in strength due to formation of noncovalent bonds. Synergizing the advantages from both categories remains challenging but pivotal for the development of the next generation of wound dressing adhesives. Here, we report a fast and reversible adhesive consisting of dynamic boronic ester covalent bonds, formed between poly(vinyl alcohol) (PVA) and boric acid (BA) for potential use as a wound dressing adhesive. Mechanical testing shows that the adhesive film has strength in shear of 61 N/cm2 and transcutaneous adhesive strength of 511 N/cm2, generated within 2 min of application. Yet the film can be effortlessly debonded when exposed to excess water. The mechanical properties of PVA/BA adhesives are tunable by varying the cross-linking density. Within seconds of activation by water, the surface boronic ester bonds in the PVA/BA film undergo fast debonding and instant softening, leading to conformal contact with the adherends and reformation of the boronic ester bonds at the interface. Meanwhile, the bulk film remains dehydrated to offer efficient load transmission, which is important to achieve strong adhesion without delamination at the interface. Whether the substrate surface is smooth (e.g., glass) or rough (e.g., hairy mouse skin), PVA/BA adhesives demonstrate superior adhesion compared to the most widely used topical skin adhesive in clinical medicine, Dermabond.

Construction of effective reproduction number of infectious disease individuals based on spatiotemporal discriminant search model: take hand-foot-mouth disease as an example.

OBJECTIVE: In order to facilitate the tracing of infectious diseases in a small area and to effectively carry out disease control and epidemiological investigations, this research proposes a novel spatiotemporal model to estimate effective reproduction number(Re)for infectious diseases, based on the fundamental concept of contact tracing. METHODS: This study utilizes the incidence of hand, foot, and mouth disease (HFMD) among children in Bishan District, Chongqing, China from 2015 to 2019. The study incorporates the epidemiological characteristics of HFMD and aims to construct a Spatiotemporal Correlation Discrimination of HFMD. Utilizing ARC ENGINE and C# programming for the creation of a spatio-temporal database dedicated to HFMD to facilitate data collection and analysis. The scientific validity of the proposed method was verified by comparing the effective reproduction number obtained by the traditional SEIR model. RESULTS: We have ascertained the optimal search radius for the spatiotemporal search model to be 1.5 km. Upon analyzing the resulting Re values, which range from 1.14 to 4.75, we observe a skewed distribution pattern from 2015 to 2019. The median and quartile Re value recorded is 2.42 (1.98, 2.72). Except for 2018, the similarity coefficient r of the years 2015, 2016, 2017, and 2019 were all close to 1, and p <0.05 in the comparison of the two models, indicating that the Re values obtained by using the search model and the traditional SEIR model are correlated and closely related. The results exhibited similarity between the Re curves of both models and the epidemiological characteristics of HFMD. Finally, we illustrated the regional distribution of Re values obtained by the search model at various time intervals on Geographic Information System (GIS) maps which highlighted variations in the incidence of diseases across different communities, neighborhoods, and even smaller areas. CONCLUSION: The model comprehensively considers both temporal variation and spatial heterogeneity in disease transmission and accounts for each individual's distinct time of onset and spatial location. This proposed method differs significantly from existing mathematical models used for estimating Re in that it is founded on reasonable scientific assumptions and computer algorithms programming that take into account real-world spatiotemporal factors. It is particularly well-suited for estimating the Re of infectious diseases in relatively stable mobile populations within small geographical areas.

Biodegradation of low-density polyethylene film by two bacteria isolated from plastic debris in coastal beach.

Low-density polyethylene (LDPE) conduces massive environmental accumulation due to its high production and recalcitrance to environment. In this study, We successfully enriched and isolated two strains, Nitratireductor sp. Z-1 and Gordonia sp. Z-2, from coastal plastic debris capable of degrading LDPE film. After a 30-day incubation at 30 ℃, strains Z-1 and Z-2 decreased the weight of branched-LDPE (BLDPE) film by 2.59 % and 10.27 % respectively. Furthermore, high temperature gel permeation chromatography (HT-GPC) analysis revealed molecular weight reductions of 7.69 % (Z-1) and 23.22 % (Z-2) in the BLDPE film. Scanning electron microscope (SEM) image showed the presence of microbial colonization and perforations on the film's surface. Fourier transform infrared spectroscopy (FTIR) analysis indicated novel functional groups, such as carbonyl and carbon-carbon double bonds in LDPE films. During LDPE degradation, both strains produced extracellular reactive oxygen species (ROS). GC-MS analysis revealed the degradation products included short-chain alkanes, alkanols, fatty acids, and esters. Genomic analysis identified numerous extracellular enzymes potentially involved in LDPE chain scission. A model was proposed suggesting a coordinated role between ROS and extracellular enzymes in the biodegradation of LDPE. This indicates strains Z-1 and Z-2 can degrade LDPE, providing a basis for deeper exploration of biodegradation mechanisms.

Research Progress on Ti3C2Tx-Based Composite Materials in Antibacterial Field.

The integration of two-dimensional Ti3C2Tx nanosheets and other materials offers broader application options in the antibacterial field. Ti3C2Tx-based composites demonstrate synergistic physical, chemical, and photodynamic antibacterial activity. In this review, we aim to explore the potential of Ti3C2Tx-based composites in the fabrication of an antibiotic-free antibacterial agent with a focus on their systematic classification, manufacturing technology, and application potential. We investigate various components of Ti3C2Tx-based composites, such as metals, metal oxides, metal sulfides, organic frameworks, photosensitizers, etc. We also summarize the fabrication techniques used for preparing Ti3C2Tx-based composites, including solution mixing, chemical synthesis, layer-by-layer self-assembly, electrostatic assembly, and three-dimensional (3D) printing. The most recent developments in antibacterial application are also thoroughly discussed, with special attention to the medical, water treatment, food preservation, flexible textile, and industrial sectors. Ultimately, the future directions and opportunities are delineated, underscoring the focus of further research, such as elucidating microscopic mechanisms, achieving a balance between biocompatibility and antibacterial efficiency, and investigating effective, eco-friendly synthesis techniques combined with intelligent technology. A survey of the literature provides a comprehensive overview of the state-of-the-art developments in Ti3C2Tx-based composites and their potential applications in various fields. This comprehensive review covers the variety, preparation methods, and applications of Ti3C2Tx-based composites, drawing upon a total of 171 English-language references. Notably, 155 of these references are from the past five years, indicating significant recent progress and interest in this research area.

A smart and responsive crystalline porous organic cage membrane with switchable pore apertures for graded molecular sieving.

Membranes with high selectivity offer an attractive route to molecular separations, where technologies such as distillation and chromatography are energy intensive. However, it remains challenging to fine tune the structure and porosity in membranes, particularly to separate molecules of similar size. Here, we report a process for producing composite membranes that comprise crystalline porous organic cage films fabricated by interfacial synthesis on a polyacrylonitrile support. These membranes exhibit ultrafast solvent permeance and high rejection of organic dyes with molecular weights over 600 g mol-1. The crystalline cage film is dynamic, and its pore aperture can be switched in methanol to generate larger pores that provide increased methanol permeance and higher molecular weight cut-offs (1,400 g mol-1). By varying the water/methanol ratio, the film can be switched between two phases that have different selectivities, such that a single, 'smart' crystalline membrane can perform graded molecular sieving. We exemplify this by separating three organic dyes in a single-stage, single-membrane process.

Ultrasonic and homogenization: An overview of the preparation of an edible protein-polysaccharide complex emulsion.

Emulsion systems are extensively utilized in the food industry, including dairy products, such as ice cream and salad dressing, as well as meat products, beverages, sauces, and mayonnaise. Meanwhile, diverse advanced technologies have been developed for emulsion preparation. Compared with other techniques, high-intensity ultrasound (HIUS) and high-pressure homogenization (HPH) are two emerging emulsification methods that are cost-effective, green, and environmentally friendly and have gained significant attention. HIUS-induced acoustic cavitation helps in efficiently disrupting the oil droplets, which effectively produces a stable emulsion. HPH-induced shear stress, turbulence, and cavitation lead to droplet disruption, altering protein structure and functional aspects of food. The key distinctions among emulsification devices are covered in this review, as are the mechanisms of the HIUS and HPH emulsification processes. Furthermore, the preparation of emulsions including natural polymers (e.g., proteins-polysaccharides, and their complexes), has also been discussed in this review. Moreover, the review put forward to the future HIUS and HPH emulsification trends and challenges. HIUS and HPH can prepare much emulsifier-stable food emulsions, (e.g., proteins, polysaccharides, and protein-polysaccharide complexes). Appropriate HIUS and HPH treatment can improve emulsions' rheological and emulsifying properties and reduce the emulsions droplets' size. HIUS and HPH are suitable methods for developing protein-polysaccharide forming stable emulsions. Despite the numerous studies conducted on ultrasonic and homogenization-induced emulsifying properties available in recent literature, this review specifically focuses on summarizing the significant progress made in utilizing biopolymer-based protein-polysaccharide complex particles, which can provide valuable insights for designing new, sustainable, clean-label, and improved eco-friendly colloidal systems for food emulsion. PRACTICAL APPLICATION: Utilizing complex particle-stabilized emulsions is a promising approach towards developing safer, healthier, and more sustainable food products that meet legal requirements and industrial standards. Moreover, the is an increasing need of concentrated emulsions stabilized by biopolymer complex particles, which have been increasingly recognized for their potential health benefits in protecting against lifestyle-related diseases by the scientific community, industries, and consumers.

Electrical Propulsion and Cargo Transport of Microbowl Shaped Janus Particles.

Herein the effective electrical propulsion, cargo trapping, and transport capabilities of microbowl-shaped Janus particles (JPs) are demonstrated and evaluated. These active JPs are made by deposition of Au and Ti layers onto sacrificial spherical polystyrene particles, followed by oxidation of the Ti to TiO2 . In contrast to the commonly studied spherical JP, the dual broken symmetry of both geometrical and electrical properties of the microbowl renders a strong dependence of its mobility and cargo loading on the order of the layering of Au and TiO2 . Specifically, an opposite direction of motion is obtained for interchanged layers of Au and TiO2 , using only electrical propulsion as the sole mechanism of motion. The concave side of the microbowl exhibits a negative dielectrophoretic trap of large size wherein trapped cargo is protected from hydrodynamic shearing, leading to an enhanced cargo loading capacity compared to that obtained using common spherical JP. Such enhanced cargo capability of the microbowl along with the ease of engineering it by interchanging the order of the layers are very attractive for future in vitro biological and biomedical applications.

Identification of a neutralizing linear epitope within the VP1 protein of coxsackievirus A10.

BACKGROUND: Coxsackievirus A10 (CV-A10) is a leading cause of hand, foot, and mouth disease (HFMD). It is necessary to identify neutralizing epitopes to investigate and develop an epitope-based vaccine against CV-A10. The viral protein VP1 is the immunodominant capsid protein and contains the critical neutralizing epitope. However, neutralizing epitopes within VP1 protein of CV-A10 have not been well characterized. METHODS: Bioinformatics techniques were applied to predict linear epitopes on the CV-A10 VP1 protein. The advanced structural features of epitopes were analyzed by three-dimensional (3D) modeling. The anticipated epitope peptides were synthesized and used to immunize mice as antigens. ELISA and micro-neutralization assay were used to determine the specific IgG antibody and neutralizing antibody titers. The protective efficacy of the epitope peptides in vivo was evaluated using a passive immunization/challenge assay. RESULTS: Three linear epitopes (EP3, EP4, and EP5) were predicted on CV-A10 VP1, all spatially exposed on the capsid surface, and exhibited adequate immunogenicity. However, only EP4, corresponding to residues 162-176 of VP1, demonstrated potent neutralization against CV-A10. To determine the neutralizing capacity of EP4 further, EP4 double-peptide was synthesized and injected into mice. The mean neutralizing antibody titer of the anti-EP4 double-peptide sera was 1:50.79, which provided 40% protection against lethal infection with CV-A10 in neonatal mice. In addition, sequence and advanced structural analysis revealed that EP4 was highly conserved among representative strains of CV-A10 and localized in the EF loop region of VP1, like EV-A71 SP55 or CV-A16 PEP55. CONCLUSIONS: These data demonstrate that EP4 is a specific linear neutralizing epitope on CV-A10 VP1. Its protective efficacy can be enhanced by increasing its copy number, which will be the foundation for developing a CV-A10 epitope-based vaccine.

Synthetic multiepitope neoantigen DNA vaccine for personalized cancer immunotherapy.

Neoantigen-based personalized vaccination has emerged as a viable method for tumor immunotherapy. Here we set up a DNA-based neoantigen vaccine platform with comprehensive identification of individual somatic mutations using whole-exome sequencing (WES) and RNA-seq, bioinformatic prediction of neo-epitopes, dendritic cell (DC)-based efficacy prevalidation of vaccine candidates, optimization of the DNA vaccine and its nanocarrier and adjuvant, and preparation of a liposome-encapsulated multiepitope DNA vaccine. The DNA vaccine was efficiently uptaken by DCs and induced effective immune response against mouse melanoma cells, leading to significant inhibition of melanoma tumor growth and reduction of lung metastasis in a mouse model. Numerous intratumoral infiltrated CD8+ T-cells with specific in vitro killing ability towards melanoma cells were identified. Our study offers evidence that a multiepitope neoantigen DNA vaccine in a nanocarrier can be exploited for personalized tumor immunotherapy and as a reliable prevalidation approach for rapid enrichment of effective neoantigens.

Three-dimensional electrodes enhance electricity generation and nitrogen removal of microbial fuel cells.

One of the critical problems for practical application of microbial fuel cells (MFCs) is the poor electron transfer between microbial cells and anode. Hence, good biocompatibility and high specific surface area of electrodes are indispensable for MFC scale-up. In this study, three-dimensional electrode MFC (3DEMFC) was developed by filling biochar between anode and cathode. Three types of biochar electrodes (biochar, biochar and zeolite mixture, and MgO-modified biochar) were employed, and the performance of 3DEMFCs treating nitrogen in wastewater was investigated. The results showed that the highest power density of MFCs was 4.45 ± 0.21 W m-3 achieved by 3DEMFC filled with MgO-modified biochar, and the overall power generation of 3DEMFCs (2.40 ± 0.28 ~ 4.45 ± 0.21 W m-3) was higher than that of MFC without biochar (1.31 ± 0.24 W m-3). The linear sweep voltammetry (LSV) results also demonstrated biochar addition to MFC was conducive to electron transfer between microbes and anode and MgO-modified biochar presented the highest coulombs transfer ability. Moreover, the highest removal efficiencies of ammonium, total nitrogen, and COD (93.6 ± 3.2%, 84.8 ± 2%, and 91.6 ± 1.3%, respectively) were achieved by 3DEMFC containing MgO-modified biochar, and simultaneous short-cut nitrification and denitrification were observed in MFCs. Furthermore, the SEM images displayed the bacteria adhesion on biochar and the biofilm dry weights of MgO-modified biochar after experiment was the highest of 103 ± 4 mg g-1 among three kinds of biochar electrodes. Therefore, the power generation and nitrogen removal conspicuously enhanced in 3DEMFCs and biochar exhibited excellent biocompatibility and distinct electrochemical performance for MFC practical applications in wastewater treatment.

Cellular Vehicles Based on Neutrophils Enable Targeting of Atherosclerosis.

Given the multiple interactions between neutrophils (NEs) and atherosclerosis (AS), in this study, we exploited NEs as cellular vehicles loaded with cationic liposomes for actively targeting atherosclerotic sites. The cellular vehicles based on NEs possess efficient internalization of cationic liposomes and sensitive response to the chemotaxis of atherosclerotic inflammatory cells, which ultimately realize the targeted delivery of the cargos into the target cells in vitro. Moreover, these effects also translated to significant enhancement of the accumulation of NEs' cargos into the atherosclerotic plaque in vivo after administering NE vehicles to the AS animal model. Consequently, cellular vehicles based on NEs could be a novel strategy for targeted delivery of payloads into atherosclerotic plaque, which would facilitate theranostics for AS and the development of anti-AS drugs to manage the disease.

POSTERIOR SCLERAL CONTRACTION TO TREAT RECURRENT OR PERSISTENT MACULAR DETACHMENT AFTER PREVIOUS VITRECTOMY IN HIGHLY MYOPIC EYES.

PURPOSE: To determine the efficacy of posterior scleral contraction (PSC) to treat recurrent or persistent macular detachment after previous vitrectomy in highly myopic eyes. METHODS: We reviewed the medical records of patients with high myopia and recurrent or persistent macular detachment after previous vitrectomy treated with PSC at our hospital between April 2013 and March 2017. Fourteen eyes (14 patients; mean age, 58.93 ± 11.08 years) were included. Sclera cross-linked with genipin was used for PSC. The desired axial length decrease was 0.1-fold. The reattachment rate, best-corrected visual acuity, and axial length changes were evaluated. RESULTS: The macular reattachment rate was 100%. In seven eyes with a silicone oil tamponade, the oil was successfully removed 2 weeks to 4 months after surgery. The best-corrected visual acuity improved significantly postoperatively (Snellen acuity improved from 20/1,000-20/400) (1.75 ± 0.90 vs. 1.34 ± 0.58 logarithm of the minimal angle of resolution; P < 0.05). Eight eyes (57.14%) improved; six eyes (43.86%) remained stable. The axial length decreased significantly postoperatively (31.32 ± 3.04 vs. 29.08 ± 3.05 mm; P < 0.05). CONCLUSION: Posterior scleral contraction is safe and effective for recurrent and persistent macular detachment after previous vitrectomy in highly myopic eyes. The silicone oil is removed after PSC, and vision can be preserved in these refractory cases.

Acute Kidney Injury Secondary to Severe Hand, Foot and Mouth Disease Caused by Enterovirus-A71: Hypertension Is a Common.

Hand, foot and mouth disease (HFMD) is a common infectious disease among children, caused primarily by human enterovirus-A71 (EV-A71) and coxsackievirus-A16 (CV-A16). To date, only two case reports mention that renal involvement can be secondary to or coexisting with CV-A16-associated HFMD. In the present report, we describe a 10-year-old girl who was infected with EV-A71 and subsequently developed a definite acute kidney injury (AKI), mainly based on the characteristic rash, virus isolation, eyelid edema, hypertension, decreased urine output, mild proteinuria and impaired renal function. She was treated with intravenous ribavirin, immunoglobulin, oral administration of nifedipine and ramipril. After 7 days of intensive observations, she recovered fully. Hypertension is a common feature in both HFMD and AKI. On one hand, hypertension serves as a risk factor for severe HFMD; on the other hand, hypertension induces AKI onset and is also deteriorated by AKI.

Alteromonas lipolytica sp. nov., a poly-beta-hydroxybutyrate-producing bacterium isolated from surface seawater.

Strain JW12T, isolated from surface seawater of the Arabian Sea, was subjected to characterization by a polyphasic taxonomic approach. Cells of the isolate were Gram-stain-negative, aerobic and rod-shaped. It accumulated poly-ß-hydroxybutyrate. On the basis of 16S rRNA gene sequence analysis, strain JW12T was closely related to Alteromonas confluentis, with 16S rRNA gene sequence similarity of 98.0 %. Phylogenetic analysis revealed that it fell within the cluster of the genus Alteromonas and represented one independent lineage with A. confluentis. The average nucleotide identity (ANI) value and the genome-to-genome distance between strain JW12T and A. confluentis KCTC 42603T were 70.0 and 21.3 %, respectively. The sole respiratory quinone was ubiquinone-8 (Q8). The principal fatty acids were summed feature 3 (C16 : 1ω7c and/or iso-C15 : 0 2-OH), C16 : 0 and C18 : 1ω7c. The major polar lipids included phosphatidylethanolamine, phosphatidylglycerol, two unidentified glycolipids and one aminophospholipid. The DNA G+C content was 48.4 mol%. Differential phylogenetic distinctiveness and chemotaxonomic differences, together with phenotypic properties obtained in this study, revealed that strain JW12T could be differentiated from the closely related species. Therefore, it is proposed that strain JW12T represents a novel species in the genus Alteromonas, for which the name Alteromonas lipolytica sp. nov. (type strain, JW12T=CGMCC 1.15735T=KCTC 52408T=MCCC 1K03175T), is proposed.

Development and evaluation of a rapid recombinase polymerase amplification assay for detection of coxsackievirus A6.

Coxsackievirus A6 (CV-A6) is an important pathogen causing hand, foot and mouth disease (HFMD). The aim of this study was to develop and evaluate a rapid real-time reverse transcription recombinase polymerase amplification (RT-RPA) assay for detection of CV-A6. The sensitivity of this assay was 202 copies/reaction, with 100 % specificity. Furthermore, this assay yielded consistent results comparable with a commercial qRT-PCR diagnostic kit. This assay is therefore potentially useful for surveillance of CV-A6 infections and outbreak control.

Aerosol Formation from OH Oxidation of the Volatile Cyclic Methyl Siloxane (cVMS) Decamethylcyclopentasiloxane.

Aerosol formation from OH oxidation of decamethylcyclopentasiloxane (D5, C10H30O5Si5), a cyclic volatile methyl siloxane (cVMS) found in consumer products, was studied in a flow-through photo-oxidation chamber with and without the presence of ammonium sulfate seed aerosol. For the unseeded experiments, chemical characterization with high-performance mass spectrometry showed that the molecular composition changed substantially with aerosol mass loading in the 1-12 µg/m3 range. Monomers (5 Si atoms/molecule) and dimers (10 Si atoms/molecule) dominated the mass spectra of aerosols at higher mass loadings, while ring-opened species (neither 5 nor 10 Si atoms/molecule) dominated the mass spectra of aerosols at lower mass loadings. Molecular signal intensity dependencies upon the aerosol volume/surface area ratio suggest that non-volatile ring-opened species are formed in the gas phase and assist particle formation through condensation, while dimers are formed by accretion reactions within the particle phase as the particles grow. These conclusions are supported by experiments in the presence of seed aerosol with a similar siloxane aerosol mass loading but higher volume/surface area ratio, where ring-opened species are much less prevalent than monomers or dimers and the aerosol yield is higher. Because of the importance of accretion chemistry, the aerosol yield from D5 oxidation is likely to be strongly dependent upon the particle size and morphology.

Design and Hemocompatibility Analysis of a Double-Suction Injection Suspension Blood Pump Using Computational Fluid Dynamics Methods.

The blood pump has become a possible solution to heart diseases. For the prevention of device failure and hemocompatibility problems, a rotary pump with suspended bearing is a preferred solution. In our previous work, a novel injection suspension method has been introduced to levitate the rotor. The suspension method is totally passive. This study aims to apply this suspension method to a double-suction pump, and the property of the pump was investigated using computational fluid dynamics (CFD) methods. The flow field of the pump is simulated based on the SST k-ω turbulent model. The characteristic curves of the pump were calculated. At the nominal working point of 5 L/min, 100 mm Hg, the suspension force acting on the rotor was detected, which could reach 0.46 N with a gap of 150 µm. We compared the pump with a previously developed single-suction injection pump to evaluate the blood compatibility of the double-suction design. The average scalar shear stress values were 3.13 Pa for the double-suction pump and 7.10 Pa for the single-suction pump. Larger volumes in the single-suction pump were exposed to shear stresses higher than 10 Pa. Thresholds for the von Willebrand factor cleavage, platelet activation, and hemolysis were defined to be 9 Pa, 50 Pa, and 150 Pa, respectively. The volume fractions for the double-suction pump are lower for all thresholds. The normalized index of hemolysis (NIH) values for the two pumps were calculated to be 0.008 g/100 L and 0.016 g/100 L. Results proved that the double-suction pump has a better hemocompatibility compared with the single-suction pump.

Drinking water treatment using a submerged internal-circulation membrane coagulation reactor coupled with permanganate oxidation.

A submerged internal circulating membrane coagulation reactor (MCR) was used to treat surface water to produce drinking water. Polyaluminum chloride (PACl) was used as coagulant, and a hydrophilic polyvinylidene fluoride (PVDF) submerged hollow fiber microfiltration membrane was employed. The influences of trans-membrane pressure (TMP), zeta potential (ZP) of the suspended particles in raw water, and KMnO4 dosing on water flux and the removal of turbidity and organic matter were systematically investigated. Continuous bench-scale experiments showed that the permeate quality of the MCR satisfied the requirement for a centralized water supply, according to the Standards for Drinking Water Quality of China (GB 5749-2006), as evaluated by turbidity (<1 NTU) and total organic carbon (TOC) (<5mg/L) measurements. Besides water flux, the removal of turbidity, TOC and dissolved organic carbon (DOC) in the raw water also increased with increasing TMP in the range of 0.01-0.05MPa. High ZP induced by PACl, such as 5-9mV, led to an increase in the number of fine and total particles in the MCR, and consequently caused serious membrane fouling and high permeate turbidity. However, the removal of TOC and DOC increased with increasing ZP. A slightly positive ZP, such as 1-2mV, corresponding to charge neutralization coagulation, was favorable for membrane fouling control. Moreover, dosing with KMnO4 could further improve the removal of turbidity and DOC, thereby mitigating membrane fouling. The results are helpful for the application of the MCR in producing drinking water and also beneficial to the research and application of other coagulation and membrane separation hybrid processes.

High-Performance Upconversion Nanoprobes for Multimodal MR Imaging of Acute Ischemic Stroke.

Multimodal magnetic resonance (MR) imaging, including MR angiography (MRA) and MR perfusion (MRP), plays a critical role in the diagnosis and surveillance of acute ischemic stroke. However, these techniques are hindered by the low T1 relaxivity, short circulation time, and high leakage rate from vessels of clinical Magnevist. To address these problems, nontoxic polyethylene glycol (PEG)ylated upconversion nanoprobes (PEG-UCNPs) are synthesized and first adopted for excellent MRA and MRP imaging, featuring high diagnostic sensitivity toward acute ischemic stroke in high-resolution imaging. The investigations show that the agent possesses superior advantages over clinical Magnevist, such as much higher relaxivity, longer circulation time, and lower leakage rate, which guarantee much better imaging efficiency. Remarkably, an extremely small dosage (5 mg Gd kg(-1) ) of PEG-UCNPs provides high-resolution MRA imaging with the vascular system delineated much clearer than the Magnevist with clinical dosage as high as 108 mg Gd kg(-1) . On the other hand, the long circulation time of PEG-UCNPs enables the surveillance of the progression of ischemic stroke using MRA or MRP. Once translated, these PEG-UCNPs are expected to be a promising candidate for substituting the clinical Magnevist in MRA and MRP, which will significantly lengthen the imaging time window and improve the overall diagnostic efficiency.

Electroosmotic pump-supported molecularly imprinted monolithic column for capillary chromatographic separation of nitrophenol isomers.

In this work, a novel molecularly imprinted polymer (MIP) monolithic column with integrated in-column electroosmotic pump (EOP) was designed and successfully prepared to facilitate the capillary chromatography with MIP column. A silica-based EOP was synthesized at the detection end of the MIP monolithic capillary column by so-gel to provide the hydrodynamic driven force for the capillary chromatography. Because of large surface area and low fluidic resistance of the silica monolith,a strong and steady EOF was generated by silica-based EOP, indicating that the EOP was quite compatible with MIP capillary column. With the sufficient EOF provided by EOP, the electro-driven based capillary chromatographic separation of nitrophenol isomers was achieved in 4-vinylpyridine-based MIP monolithic capillary, which was originally proved infeasible because of the EOF shortage. No significant influence upon the specific recognition of the MIP was found due to the setting of EOP after the detection window of the column. The influence of experimental parameters on the EOF such as voltage and pH value of running buffer was investigated. The column was also evaluated by capillary liquid chromatographic mode to compare with EOP-driven capillary chromatography. Higher column efficiency was obtained by EOP-driven separation with improved peak shape. The results suggested that EOP-supported technique would be a good way to solve the problem of weak EOF generation in electro-driven capillary chromatography.