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Small interfering RNA (siRNA)-based therapy has emerged as a powerful therapeutic tool due to its target-specific gene silencing. However, the therapeutic efficacy has been limited by poor cellular uptake, and therefore delivery vehicles are required to improve the cellular uptake. Herein, guanidinium-incorporated polyether-based block copolyelectrolytes were developed for improved cellular uptake and consequently increased gene silencing efficiency. Guanidinium-functionalized poly(ethylene oxide-b-allyl glycidyl ether) (G-PEO-PAGE) were prepared by living anionic ring opening polymerization of allyl glycidyl ether and post-modification to introduce guanidinium groups. G-PEO-PAGE provides efficient complexation with siRNA due to highly cationic charges of the guanidinium groups at physiological pH, resulting in significantly improved cellular uptake of siRNA and consequently increased gene silencing efficiency. In addition, G-PEO-PAGE showed significantly lower cytotoxicity compared to branched polyethylenimine as a commercial counterpart. This study demonstrates that guanidinium-incorporated block copolyelectrolytes have a great potential for efficient and low toxic siRNA delivery.

The relaxation dynamics of poly(ethyl glycidyl ether-co-isopropyl glycidyl ether-b-ethylene oxide-b-ethyl glycidyl ether-co-isopropyl glycidyl ether) triblock copolymer hydrogels were investigated ...

Complex coacervate core hydrogels were formed by simply mixing two oppositely charged polyether-based ABA triblock copolyelectrolyte solutions, where A blocks functionalized with either ammonium or...

The effects of voltage on the methane production rate (k) of various types of anaerobic sludge biomasses are quantitatively demonstrated. Voltage is supplied to the anaerobic digestion (AD) sludges independently and quickly improves the methane production rates and specific methanogenic activities (SMAs), regardless of bio-electrochemical activation of the sludge. This supports previous findings that bio-electrochemical AD (BEAD) shows higher stabilization and methane production rates than those of AD. However, in reactors fed with H2/CO2, SMA and k are not significantly increased by the voltage supply, indicating that direct electron transfer for hydrogenotrophic methanogenesis is not a major methane formation pathway. The voltage supply contributed to indirect electron transfer for H2 production. Therefore, indirect electron transfer via H2 is a significant factor in hydrogenotrophic methanogenesis. These findings indicate changes in the general pathways of AD achieved using a voltage supply and provide a better understanding of previous BEAD studies.

Salinization of agricultural lands, particularly rice paddies, results in the drastic decline of crop yields. Soil salinization impacts the plant physiology by inducing salt stress which may leads to osmotic stress, ionic stress and water-related nutrient imbalance. These imbalances necessitate the need for plants to produce osmolytes including proline and glycine betaine. This study aimed to elucidate the dynamic changes in proline and glycine betaine accumulation modulated by the inoculation of Brevibacterium linens RS16 in salt-sensitive and moderately salt-tolerant rice plants under salt stress conditions. This study showed the interaction of four major factors including rice genotypes with differing tolerance to salt stress, length of exposure to salt stress, level of salt stress and effects of inoculation. Salt stress resulted in significant reduction in plant growth parameters with the salt-sensitive rice genotype (IR29) having a more significant growth reduction. Both the salt-sensitive and salt-tolerant rice genotypes increased in total proline and glycine betaine accumulation at 3 days and 10 days after subjecting under 50 mM and 150 mM salt stress conditions. A significant increase in proline and glycine betaine was observed in the salt-sensitive genotype after 10 days under 50 mM and 150 mM salt stress conditions. Inoculation of the rice genotypes with B. linens RS16 resulted in the improvement of plant growth parameters in both rice genotypes, and total proline and glycine betaine accumulation, especially in IR29. This study showed that proline and glycine betaine are compatible osmolytes of rice under salt stress, and that inoculation of rice genotypes with B. linens RS16 mediated salt tolerance through improvement of plant growth parameters and proline and glycine betaine accumulation in rice plants.

We examined the packing structure of polystyrene-coated gold nanoparticles (Au@PS) as a function of grafting density. A series of Au@PS nanoparticles with grafting densities in the range of 0.51–1.94 chains nm–2 were prepared by a ligand exchange process using thiol-terminated PS and then self-assembled at a liquid–air interface. We observed a transition from disordered to body-centered cubic (bcc) to face-centered cubic (fcc) arrangements with increasing grafting density, even though the ligand length-to-core radius ratio (λ) was as high as 3.0, a condition that typically favors nonclose-packed bcc symmetry in the self-assembly of hard nanoparticles. To explain this phenomenon, we define λeff to include the concentrated polymer brush regime as part of the “hard core”, which predicts that the softness of Au@PS nanoparticles is reduced from 1.53 to 0.14 in a theta solvent as the grafting density increases from 0.51 to 1.94 chains nm–2. This new definition of λ can also predict the effective radii of nanopa...

Artificial intelligence (AI)-based diagnostic tools have been accepted in ophthalmology. The use of retinal images, such as fundus photographs, is a promising approach for the development of AI-based diagnostic platforms. Retinal pathologies usually occur in a broad spectrum of eye diseases, including neovascular or dry age-related macular degeneration, epiretinal membrane, rhegmatogenous retinal detachment, retinitis pigmentosa, macular hole, retinal vein occlusions, and diabetic retinopathy. Here, we report a fundus image-based AI model for differential diagnosis of retinal diseases. We classified retinal images with three convolutional neural network models: ResNet50, VGG19, and Inception v3. Furthermore, the performance of several dense (fully connected) layers was compared. The prediction accuracy for diagnosis of nine classes of eight retinal diseases and normal control was 87.42% in the ResNet50 model, which added a dense layer with 128 nodes. Furthermore, our AI tool augments ophthalmologist’s performance in the diagnosis of retinal disease. These results suggested that the fundus image-based AI tool is applicable for the medical diagnosis process of retinal diseases.

The tight regulation of local auxin homeostasis and signalling maxima in xylem precursor cells specifies the organising activity of the vascular cambium and consequently promotes xylem differentiation and wood formation. However, the molecular mechanisms underlying the local auxin signalling maxima in the vascular cambium are largely unknown. Here, we reveal that brassinosteroid (BR)-activated WALLS ARE THIN1 (WAT1) facilitates wood formation by enhancing local auxin signalling in the vascular cambium in Solanum lycopersicum. Growth defects and low auxin signalling readouts in the BR-deficient tomato cultivar, Micro-Tom, were associated with a novel recessive allele, Slwat1-copi, created by the insertion of a retrotransposon in the last exon of the SlWAT1 locus. Molecular and genetic studies by generating the gain-of-function and loss-of-function tomato mutants revealed that SlWAT1 is a critical regulator for fine tuning local auxin homeostasis and signalling outputs in vascular cambium to facilitate secondary growth. Finally, we discovered that BR-regulated SlBZR1/2 directly activated downstream auxin responses by SlWAT1 upregulation in xylem precursor cells to facilitate xylem differentiation and subsequent wood formation. Our data suggest that the BR-SlBZR1/2-WAT1 signalling network contributes to the high level of auxin signalling in the vascular cambium for secondary growth.

Various microorganisms are involved in nitrogen removal, and their group compositions depend closely on operating parameters. The structures and functions of nitrification microorganisms in full-scale anaerobic-anoxic–oxic (A2/O) and oxidation ditch processes were analyzed using metagenomics and canonical correspondence analysis. The community structure of ammonia-oxidizing archaea in the oxidation ditch was 3.8 (winter) – 6.3 (summer) times higher than in A2/O, and the complete ammonia oxidizer was only found in the oxidation ditch process. The canonical correspondence analysis of various environmental variables showed that Nitrosomonadales, Crenarchaeota, and Nitrospira inopinata correlate highly with nitrification, and Nitrospira was involved in NO2−-N oxidation rather than Nitrobacter. The longer solid and hydraulic retention times in the oxidation ditch were more effective in achieving a wider range of novel nitrification than A2/O. This result indicates that microbial communities of novel nitrifiers and ammonia-oxidizing archaea improved in the oxidation ditch process, significantly contributing to stable nitrogen removal.

BR signaling pathways facilitate xylem differentiation and wood formation by fine tuning SlBZR1/SlBZR2-mediated gene expression networks involved in plant secondary growth. Brassinosteroid (BR) signaling and BR crosstalk with diverse signaling cues are involved in the pleiotropic regulation of plant growth and development. Recent studies reported the critical roles of BR biosynthesis and signaling in vascular bundle development and plant secondary growth; however, the molecular bases of these roles are unclear. Here, we performed comparative physiological and anatomical analyses of shoot morphological growth in a cultivated wild-type tomato (Solanum lycopersicum cv. BGA) and a BR biosynthetic mutant [Micro Tom (MT)]. We observed that the canonical BR signaling pathway was essential for xylem differentiation and sequential wood formation by facilitating plant secondary growth. The gradual retardation of xylem development phenotypes during shoot vegetative growth in the BR-deficient MT tomato mutant recovered completely in response to exogenous BR treatment or genetic complementation of the BR biosynthetic DWARF (D) gene. By contrast, overexpression of the tomato Glycogen synthase kinase 3 (SlGSK3) or CRISPR-Cas9 (CR)-mediated knockout of the tomato Brassinosteroid-insensitive 1 (SlBRI1) impaired BR signaling and resulted in severely defective xylem differentiation and secondary growth. Genetic modulation of the transcriptional activity of the tomato Brassinazole-resistant 1/2 (SlBZR1/SlBZR2) confirmed the positive roles of BR signaling pathways for xylem differentiation and secondary growth. Our data indicate that BR signaling pathways directly promote xylem differentiation and wood formation by canonical BR-activated SlBZR1/SlBZR2.

Elastin-like polypeptides (ELPs) are stimulusresponsive protein-based biopolymers that exhibit phase transition behavior. Some ELP block copolymers can assemble spherical nanoparticles with thermo-sensitivity. For this reason, thermo-responsive nanoparticles derived from ELP block copolymers have been utilized in the biomedical field. In this study, four different ELP block copolymers constituted three diblocks and one triblock were synthesized. Physical properties of these self-assembled micelles were then investigated according to their block lengths and distributions. In addition, drug capturing capacities of these micelles and aggregates were explored by changing solution temperature.

Microalgal&ndash, bacterial consortia are considered an alternative method to conventional wastewater treatment processes with several benefits, such as low oxygen production cost and reduced emission of carbon dioxide resulting from photosynthetic activity. Besides, microalgae effectively remove various emerging contaminants and heavy metals that are hardly removed by conventional wastewater treatment processes. The purpose of this study is finding optimal operation conditions (e.g., light wavelengths, light intensity, microalgal&ndash, bacterial consortia biomass) when applying microalgae in wastewater treatment system. Firstly, reduced transmittance was monitored at four different wavelengths (i.e., blue, green, red, and white light) and at various concentrations of microalgal&ndash, bacterial consortia. Light transmittance rates were rapidly reduced as the biomass increased, where the highest transmittance was observed in green light. Secondly, the reduction of oxygen production over time, by the inhibition of the photosynthetic activity, was tested as the light intensity increased at four different wavelengths and at low (100 mg L&minus, 1) and high (500 mg L&minus, 1) concentrations of microalgal&ndash, bacterial consortia. The observations and subsequent statistical analyses verify that microalgal&ndash, bacterial consortia show the strongest resistance to the inhibition of the photosynthetic activity in green light, with white coming next, when the intensity of light is increased.

Pairs of ionic group dependence of the structure of a complex coacervate core micelle (C3M) in an aqueous solution was investigated using DLS, cryo-TEM, and SANS with a contrast matching technique and a detailed model analysis. Block copolyelectrolytes were prepared by introducing an ionic group (i.e., ammonium, guanidinium, carboxylate, and sulfonate) to poly(ethylene oxide-b-allyl glycidyl ether) (NPEO = 227 and NPAGE = 52), and C3Ms were formed by simple mixing of two oppositely-charged block copolyelectrolyte solutions with the exactly same degree of polymerization. All four C3Ms are spherical with narrow distribution of micelle dimension, and the cores are significantly swollen by water, resulting in relatively low brush density of PEO chains on the core surface. With the pair of strong polyelectrolytes, core radius and aggregation number increases, which reflects that the formation of complex coacervates are significantly sensitive to the pairs of ionic groups rather than simple charge pairing.

Despite the growing interest in amphiphilic block copolymers for their application in micelles as ideal drug delivery carriers, there remain some challenges related to biocompatibility, stability, degradability, and loading efficiency of the micelles. Herein, we report a novel hydrophobic, pH-responsive epoxide monomer, tetrahydropyranyl glycidyl ether (TGE). Anionic ring-opening polymerization affords the controlled synthesis of a series of its homopolymers (PTGE) and amphiphilic polymers, poly(ethylene glycol)-block-poly(tetrahydropyranyl glycidyl ether) (PEG-b-PTGE). Interestingly, these block copolymers with cyclic TGE moieties showed superior stability in biological media, high loading capacity, tunable release, and controllable degradation compared to the block copolymers with its acyclic analogue, 1-ethoxyethyl glycidyl ether (EEGE), widely employed in polyether, which satisfy all the required design principles and address the challenges in drug delivery systems. The superior biocompatibility coupled with the high stability of the novel functional epoxide monomer is anticipated to lead to the development of a versatile platform for smart drug delivery systems.

The effects of hydrodynamics and alum dose on particle growth were investigated by monitoring particle counts in a rapid mixing process. Experiments were performed to measure the particle growth and breakup under various conditions. The rapid mixing scheme consisted of the following operating parameters: Velocity gradient (G) (200-300 s -1 ), alum dose (10-50 mg/L) and mixing time (30-180 s). The Poisson regression model was applied to assess the effects of the doses and velocity gradient with mixing time. The mechanism for the growth and breakup of particles was elucidated. An increase in alum dose was found to accelerate the particle count reduction. The particle count at a G value of 200 s -1 decreased more rapidly than those at 300 s -1 . The growth and breakup of larger particles were more clearly observed at higher alum doses. Variations of particles due to aggregation and breakup of micro-flocs in rapid mixing step were interactively affected by G, mixing time and alum dose. Micro-flocculation played an important role in a rapid mixing process.

The sdu1+ gene encodes Sdu1, a PPPDE superfamily member of deubiquitinating enzymes (DUBs) in Schizosaccharomyces pombe. Sdu1 was previously shown to contain an actual ubiquitin C-terminal hydrolase (UCH) activity using the recombinant plasmid pYSTP which harbors the sdu1+ gene. This work was designed to assess a thermotolerant role of Sdu1 against high incubation temperatures. In the temperature-shift experiments, the S. pombe cells harboring pYSTP grew much better after the shifts to 37˚C and 42˚C, when compared with the vector control cells. After being shifted to 37˚C and 42˚C for 6 h, the S. pombe cells harboring pYSTP contained lower reactive oxygen species (ROS) levels, compared with the vector control cells. The nitric oxide (NO) levels of the S. pombe cells harboring pYSTP were slightly lower than those of the vector control cells in the absence or presence of the temperature shifting. The total glutathione (GSH) levels of the S. pombe cells harboring pYSTP were significantly higher than those of the vector control cells. Total superoxide dismutase (SOD) and GSH peroxidase activities were also higher in the S. pombe cells harboring pYSTP after the temperature shifts than in the vector control cells. In brief, the S. pombe Sdu1 plays a thermotolerant role against high incubation temperature through the down-regulation of ROS and NO and the up-regulation of total GSH content, total SOD and GSH peroxidase activities.

In this study, we develop a methodology to estimate the effectiveness of ramp metering in reducing CO2 emissions. Ramp metering is one of several Intelligent Transportation Systems (ITS) applications to control traffic flow. In this paper in order to estimate the reduced emissions, we followed the procedure supported by the United Nations Framework Convention on Climate Change (UN-FCCC). And ramp metering causes some drivers to change their routes and affects CO2 emissions on the ramp and on the main lane. With these issues in mind, we performed Stated Preference analysis to determine the degree of driver preference for individual traffic situations.The Traffic Software Integrated System (TSIS) simulation program was used to verify the CO2 measurement model. The TSIS simulation showed that the reduction in CO2 emissions was 818.4 kg/h and that the decrease in the effectiveness was 7.3%. It also revealed that ramp metering reduced the CO2. emissions to 3,273.6kg emissions per day and 1,194.9 ton per year. In conclusion we found that ramp metering is effective in reducing CO2 emissions.

Removal of odor-causing compounds (OCCs) including geosmin and 2-methylisoborneol (2-MIB), well known to cause the musty and earthy odor in drinking water, was investigated using powdered activated carbon (PAC) adsorption and air stripping processes. Removal by air stripping was mainly affected by aeration flow rates with volumetric mass-transfer rates of 0.002–0.005 min−1. Aeration also proved efficient for marginal removal of geosmin and 2-MIB in conjunction with PAC adsorption. Removal efficiencies increased depending on both PAC dose and aeration time in the aerated PAC contactor. PAC adsorption with aeration reduced the required PAC dose and contact time for removal of these compounds, compared with PAC adsorption alone. Removal efficiency of geosmin above 93% was improved by simultaneous PAC adsorption and air stripping under the same conditions. 2-MIB was relatively less amenable to removal and removal efficiency was about 58% by PAC adsorption at a dose of 15 mg l−1, 14% by air stripping at aeration flow rate of 15 l min−1 with 60 min aeration and 74% by simultaneous PAC adsorption and air stripping, respectively. Aeration flow rate, contact time and PAC dose were the critical factors in PAC adsorption with aeration for OCC removal and optimum conditions are suggested.