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Mesoporous manganese dioxide (mMnO2) was first synthesized for the loading of methotrexate (MTX), and then dopamine was in situ polymerized on the surface of the MTX‐loaded mMnO2 (mMnO2‐MTX) in an alkaline solution to encapsulate the drug in the mesopores of mMnO2. Both low pH and glutathione (GSH) can result in the degradation of mMnO2 and poly(dopamine) (PDA), and thus the delivery of MTX from the mMnO2‐MTX‐PDA can be triggered by low pH and GSH. Near‐infrared (NIR) light‐responsive delivery of MTX can be achieved owing to the outstanding photothermal conversion capability of PDA; on the other hand, the mMnO2‐MTX‐PDA can be utilized for photothermal therapy under the irradiation of NIR light due to the elevated temperature. The results of cytotoxicity test demonstrate that the pH, GSH, and NIR light tri‐responsive drug‐controlled delivery system has excellent biocompatibility, while exhibits pronounced growth inhibition against murine breast tumor cell line 4T1. [ABSTRACT FROM AUTHOR]

Flood retention lakes (RLs) are widely employed in rural‐urban catchments with low impacts on the natural environment. However, insights are lacking regarding the control of climate conditions on RLs' performances and how they are affected by different geographic configurations. This study applies a 2D hydrodynamic model to perform a catchment‐scale performance assessment of RLs beyond the scope of analytical and hydrological models. We conduct extensive numerical experiments of rainstorm‐induced flooding in a rural‐urban catchment with a constructed RL and blueprinted ones upstream. Results demonstrate an L‐shaped band of satisfactory performance of the current RL in the frequency‐duration diagram, which coincides with short return periods (<5 years) and long durations (>4 hr), or short durations (<3 hr) and moderate to long return periods (5–50 years); such L‐shaped pattern is also valid for additional RLs and their combinations. With the increase in event size, the first two modes of RL performance (out of four) correspond to effective flood mitigation. When working jointly, RLs with series configurations are more effective in reducing the mainstream flood peaks, while parallel connections provide a greater spatial extent of flood hazard mitigation. For both series and parallel configurations, the upstream‐weighted settings tend to outperform downstream‐weighted ones under more extreme events; the decentralized arrangement in the urban area yields more benefits in spatial flood hazard mitigation compared to the centralized case. The study highlights the critical role of rainstorm severity (with possible spatiotemporal variabilities) in controlling RL performances despite various configurations and hydraulic settings. Key Points: An L‐shaped band on the frequency‐duration diagram indicates the dominance of climate conditions on retention lake (RL) performancesRLs configured in parallel mitigate flood hazard to a larger extent while those in series are superior for reducing mainstream flood peaksRLs with upstream‐weighted capacities are more effective than downstream‐weighted ones in extreme events [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to develop deep learning (DL) models for differentiating between eosinophilic chronic rhinosinusitis (ECRS) and non‐ECRS (NECRS) on preoperative CT. Design: Axial spiral CT images were pre‐processed and used to build the dataset. Two semantic segmentation models based on U‐net and Deeplabv3 were trained to segment the sinus area on CT images. All patient images were segmented using the better‐performing segmentation model and used for training and testing of the transferred efficientnet_b0, resnet50, inception_resnet_v2, and Xception neural networks. Additionally, we evaluated the performances of the models trained using each image and each patient as a unit. Participants: A total of 878 chronic rhinosinusitis (CRS) patients undergoing nasal endoscopic surgery at Renmin Hospital of Wuhan University (Hubei, China) between October 2016 to June 2021 were included. Main outcome measures: The precision of each model was assessed based on the receiver operating characteristic curve. Further, we analyzed the confusion matrix and accuracy of each model. Results: The Dice coefficients of U‐net and Deeplabv3 were 0.953 and 0.961, respectively. The average area under the curve and mean accuracy values of the four networks were 0.848 and 0.762 for models trained using a single image as a unit, while the corresponding values for models trained using each patient as a unit were 0.893 and 0.853, respectively. Conclusions: Combining semantic segmentation with classification networks could effectively distinguish between patients with ECRS and those with NECRS based on preoperative sinus CT images. Furthermore, labeling each patient to build a dataset for classification may be more reliable than labeling each medical image. [ABSTRACT FROM AUTHOR]

A novel Zn‐coordination covalent porphyrin assembly (TCPP‐BZA‐Zn) is designed. The assembly structure is synthesized through the amidation reaction between the porphyrin terminal carboxyl group and the amino group of benzylamine (BZA), and further assembled through π–π stacking. In particular, the inherently ordered structure of TCPP‐BZA‐Zn with Zn as the catalytic active center endows the porphyrin assembly structure with several obvious advantages, such as high ion transport properties and high electrocatalytic performance. In the presence of hydrogen peroxide as a co‐reaction reagent, TCPP‐BZA‐Zn/GCE showed excellent ECL behavior. The amplification phenomenon of ECL was further studied by cyclic voltammetry and the corresponding mechanism was proposed. Based on TCPP‐BZA‐Zn, an electrochemiluminescence sensor was constructed for copper ion detection. The ECL intensity of the sensor shows a good linear relationship with the concentration of copper ion in the range of 10 nM–1 mM, and the detection limit is 1.3 nM. [ABSTRACT FROM AUTHOR]

The integration of an ingestible dosage form with sensing, actuation, and drug delivery capabilities can enable a broad range of surgical‐free diagnostic and treatment strategies. However, the gastrointestinal (GI) tract is a highly constrained and complex luminal construct that fundamentally limits the size of an ingestible system. Recent advancements in mesoscale magnetic crawlers have demonstrated the ability to effectively traverse complex and confined systems by leveraging magnetic fields to induce contraction and bending‐based locomotion. However, the integration of functional components (e.g., electronics) in the proposed ingestible system remains fundamentally challenging. Herein, the creation of a centralized compartment in a magnetic robot by imparting localized flexibility (MR‐LF) is demonstrated. The centralized compartment enables MR‐LF to be readily integrated with modular functional components and payloads, such as commercial off‐the‐shelf electronics and medication, while preserving its bidirectionality in an ingestible form factor. The ability of MR‐LF to incorporate electronics, perform drug delivery, guide continuum devices such as catheters, and navigate air–water environments in confined lumens is demonstrated. The MR‐LF enables functional integration to create a highly integrated ingestible system that can ultimately address a broad range of unmet clinical needs. An interactive preprint version of the article can be found at https://doi.org/10.22541/au.166274072.23086985/v1. [ABSTRACT FROM AUTHOR]

Geophysical mass flows impacting flexible barriers can create complex flow patterns and multiway solid‐fluid‐structure interactions, wherein estimates of impact loads rely predominantly on analytical or simplified solutions. However, an examination of the fundamental relations, applicability, and underlying mechanisms of these solutions has been so far elusive. Here, using a coupled continuum‐discrete method, we systematically examine the physical laws of multiphase, multiway interactions between geophysical flows of variable natures, and a permeable flexible ring net barrier system. This model well captures the essential physics observed in experiments and field investigations. Our results reveal for the first time that unified bi‐linear laws underpin widely used analytical and simplified solutions, with inflection points caused by the transitions from trapezoid‐shaped to triangle‐shaped dead zones. Specifically, the peak impact load increases bi‐linearly with increasing Froude number, peak cable force, or maximum barrier deformation. Flow materials (wet vs. dry) and impact dynamics (slow vs. fast) jointly drive the patterns of identified bi‐linear correlations. These findings offer a physics‐based, significant improvement over existing solutions to impact problems for geophysical flows. Plain Language Summary: Flexible barriers are increasingly used worldwide to mitigate debris flows, debris/rock/snow avalanches, and rockfalls. Although many methods exist to estimate critical design factors of flexible barriers, a systematic examination of their applicability and underlying relations remains elusive. The status quo has been largely caused by the challenges of capturing and quantifying the multiphase, multiway flow‐barrier interactions. Here, we perform a series of hybrid solid‐fluid simulations to explore the impact of debris flows/avalanches and rock avalanches on a flexible barrier system. Our numerical predictions of critical physical processes show reasonable consistency with experimental and field observations. For the first time, the physics‐based numerical measures of the flow‐barrier forces, in‐barrier forces, and barrier load‐deformation relations reveal the unified bi‐linear laws behind widely used methods. We find that the flow‐specific turning points of the bi‐linear laws are due to the changes from trapezoid‐shaped to triangle‐shaped jammed regions formed upstream of the barrier. Our findings quantitatively explain how flow properties (e.g., wet vs. dry and slow vs. fast) control the obtained bi‐linear laws. This study provides a crucial improvement over widely used methods for geohazard scientists and engineers to impact problems for geophysical flows. Key Points: We present numerical measures of the impact loads of debris flows/avalanches and rock avalanches on a flexible ring net barrier systemBi‐linear laws relate peak impact to Fr, peak cable force, or maximum barrier deformation with turning points due to shifts of dead zonesFlow materials and dynamics jointly control the obtained bi‐linear laws, which underpin widely used analytical and simplified solutions [ABSTRACT FROM AUTHOR]

Background: Training deep learning (DL) models to automatically recognize diseases in nasopharyngeal MRI is a challenging task, and optimizing the performance of DL models is difficult. Purpose: To develop a method of training anatomical partition‐based DL model which integrates knowledge of clinical anatomical regions in otorhinolaryngology to automatically recognize diseases in nasopharyngeal MRI. Study Type: Single‐center retrospective study. Population: A total of 2485 patients with nasopharyngeal diseases (age range 14–82 years, female, 779[31.3%]) and 600 people with normal nasopharynx (age range 18–78 years, female, 281[46.8%]) were included. Sequence: 3.0 T; T2WI fast spin‐echo sequence. Assessment: Full images (512 × 512) of 3085 patients constituted 100% of the dataset, 50% and 25% of which were randomly retained as two new datasets. Two new series of images (seg112 image [112 × 112] and seg224 image [224 × 224]) were automatically generated by a segmentation model. Four pretrained neural networks for nasopharyngeal diseases classification were trained under the nine datasets (full image, seg112 image, and seg224 image, each with 100% dataset, 50% dataset, and 25% dataset). Statistical Tests: The receiver operating characteristic curve was used to evaluate the performance of the models. Analysis of variance was used to compare the performance of the models built with different datasets. Statistical significance was set at P < 0.05. Results: When the 100% dataset was used for training, the performances of the models trained with the seg112 images (average area under the curve [aAUC] 0.949 ± 0.052), seg224 images (aAUC 0.948 ± 0.053), and full images (aAUC 0.935 ± 0.053) were similar (P = 0.611). When the 25% dataset was used for training, the mean aAUC of the models that were trained with seg112 images (0.823 ± 0.116) and seg224 images (0.765 ± 0.155) was significantly higher than the models that were trained with full images (0.640 ± 0.154). Data Conclusion: The proposed method can potentially improve the performance of the DL model for automatic recognition of diseases in nasopharyngeal MRI. Level of Evidence: 4 Technical Efficacy Stage: 1 [ABSTRACT FROM AUTHOR]

Objective: Preterm infants are at a high risk of developing BPD. Although progression in neonatal care has improved, BPD still causes significant morbidity and mortality, which can be attributed to the limited therapeutic choices for BPD. This review discusses the potential of MSC in treating BPD as well as their hurdles and possible solutions. Data Sources: The search for data was not limited to any sites but was mostly performed on all clinical trials available in ClinicalTrials.gov as well as on PubMed by applying the following keywords: lung injury, preterm, inflammation, neonatal, bronchopulmonary dysplasia and mesenchymal stem cells. Study Selections: The articles chosen for this review were collectively determined to be relevant and appropriate in discussing MSC not only as a potential treatment strategy for curbing the incidence of BPD but also including insights on problems regarding MSC treatment for BPD. Results: Clinical trials regarding the use of MSC for BPD had good results but also illustrated insights on problems to be addressed in the future regarding the treatment strategy. Despite that, the clinical trials had mostly favourable reviews. Conclusion: With BPD existing as a constant threat and there being no permanent solutions, the idea of regenerative medicine such as MSC may prove to be a breakthrough strategy when it comes to treating BPD. The success in clinical trials led to the formulation of prospective MSC‐derived products such as PNEUMOSTEM®, and there is the possibility of a stem cell medication and permanent treatment for BPD in the near future. [ABSTRACT FROM AUTHOR]

Flexible, slit, and rigid barriers are common countermeasures to mitigate natural geophysical mass flows, but presently, quantitative comparisons of their performance are lacking, due to the challenges involved in accurately representing the multi‐body and multi‐phase interactions. This study presents a numerical appraisal on this issue using a physics‐based coupled computational fluid dynamics and discrete element method (CFD‐DEM). A geophysical flow is considered as a mixture of discrete gap‐graded particles (DEM) and a continuous viscous slurry (CFD), whereas a permeable and deformable barrier structure can be modeled by DEM. The in‐flow multiphase interactions and flow‐barrier interactions can be rigorously modeled by a coupling scheme between DEM and CFD. Our numerical simulations reasonably capture both field and experimental observations on key features of flow‐barrier interactions and barrier responses. The different intercepting mechanisms of three barriers via pile‐up and runup modes are revealed by qualitative and quantitative characterizations. Flexible barriers perform the best under runup mode regarding much larger peak load reduction ratios (up to 89%) due to their high permeability and Fr‐dependent load‐deflection behavior. We further compile a barrier‐specific design diagram that suggests existing analytical models calibrated by limited experiments may underestimate the peak impact for slit and rigid barriers due to their neglect of large solid particles in the impinging flows while leading to overestimations for flexible barriers owing to inappropriate representations of barrier permeability and structural deformability. Our findings may offer a basis for model improvements and developments in practical barrier selection and design. Plain Language Summary: Engineers commonly use flexible, open‐type, and closed‐type barriers to reduce the adverse impacts of natural geophysical mass flows. However, the selection and design of barriers mainly rely on engineering experience and simplified models. We present a numerical study based on the coupled fluid‐solid modeling to offer quantitative reference on this issue. The numerical framework employed enables a unified description of a geophysical flow as a mixture of solid particles and a continuous viscous slurry and any of the three barrier types, offering a consistent comparison basis. We compare the different intercepting mechanisms of three types of barriers in resisting an impinging flow and identify their intertwined dependence of incoming flow characteristics, barrier deformability and passing ability, and peak impact loads. A flexible barrier is found to outperform the other two in achieving better peak load reduction ratios (up to 89%) with a runup mode, due to its high passing ability and load‐deflection behavior. The compilation of a unified barrier‐specific design diagram highlights the influences of barrier passing ability, structure deformability, and large solid particles on the peak impacts. This work could help for developing better analytical models on specific barrier design to mitigate natural geohazards caused by geophysical mass flows. Key Points: Coupled fluid‐solid simulations of geophysical flows against flexible, slit and rigid barriers reveal their distinct intercepting mechanismsThe flexible barrier performs the best under runup mode owing to its high permeability and Fr‐dependent load‐deflection behaviorCompilation of a barrier‐specific design diagram highlights the effects of large particles, barrier permeability, and structure deformability [ABSTRACT FROM AUTHOR]

A simple drug controlled delivery system is facilely designed for pH‐responsive delivery of methotrexate (MTX), an anticancer drug. Aminated mesoporous silica nanoparticles (AMSNs) were first synthesized for the loading of MTX, and then the MTX‐loaded AMSN (AMSN‐MTX) was encapsulated with hyaluronic acid (HA) through electrostatic attractions. Successful preparation of the HA‐encapsulated AMSN‐MTX (AMSN‐MTX‐HA) is confirmed by different characterizations such as scanning electron microscopy, Fourier transform infrared, x‐ray diffraction, and so on. Because the protonation/deprotonation of HA is closely related to pH, the electrostatic interactions between HA and AMSN depend closely on the pH of the medium and thus pH‐responsive delivery of MTX is achieved. The release kinetic data of MTX from the carrier fit well to Higuchi and Korsmeyer‐Peppas models. Cell experiments indicate that the developed AMSN‐MTX‐HA displays high inhibitory effect on hepatoma (SMMC‐7721) cells while the drug‐free carrier of AMSN‐HA has good biocompatibility. [ABSTRACT FROM AUTHOR]

Ageing and age‐related diseases share some basic origin that largely converges on inflammation. Precisely, it boils down to a common pathway characterised by the appearance of a fair amount of proinflammatory cytokines known as inflammageing. Among the proposed treatment for antiageing, MSCs gained attention in recent years. Since mesenchymal stem cells (MSCs) can differentiate itself into a myriad of terminal cells, previously it was believed that these cells migrate to the site of injury and perform their therapeutic effect. However, with the more recent discovery of huge amounts of paracrine factors secreted by MSCs, it is now widely accepted that these cells do not engraft upon transplantation but rather unveil their benefits through excretion of bioactive molecules namely those involved in inflammatory and immunomodulatory activities. Conversely, the true function of these paracrine changes has not been thoroughly investigated all these years. Hence, this review will describe in detail on ways MSCs may capitalize its paracrine properties in modulating antiageing process. Through a comprehensive literature search various elements in the antiageing process, we aim to provide a novel treatment perspective of MSCs in antiageing related clinical conditions. [ABSTRACT FROM AUTHOR]

Reinforcement learning control methods can impart robots with the ability to discover effective behavior, reducing their modeling and sensing requirements, and enabling their ability to adapt to environmental changes. However, it remains challenging for a robot to achieve navigation in confined and dynamic environments, which are characteristic of a broad range of biomedical applications, such as endoscopy with ingestible electronics. Herein, a compact, 3D‐printed three‐linked‐sphere robot synergistically integrated with a reinforcement learning algorithm that can perform adaptable, autonomous crawling in a confined channel is demonstrated. The scalable robot consists of three equally sized spheres that are linearly coupled, in which the extension and contraction in specific sequences dictate its navigation. The ability to achieve bidirectional locomotion across frictional surfaces in open and confined spaces without prior knowledge of the environment is also demonstrated. The synergistic integration of a highly scalable robotic apparatus and the model‐free reinforcement learning control strategy can enable autonomous navigation in a broad range of dynamic and confined environments. This capability can enable sensing, imaging, and surgical processes in previously inaccessible confined environments in the human body. [ABSTRACT FROM AUTHOR]

Poly(p‐aminobenzene sulfonic acid) (pABSA) was electrodeposited onto the surface of a glassy carbon electrode (GCE), which was then used for the preconcentration of l‐tryptophan (l‐Trp) due to the electrostatic and π–π interactions between pABSA and l‐Trp. Polypyrrole (PPy) was electrodeposited onto the surface of the l‐Trp enriched pABSA, and then the l‐Trp templates were removed, resulting in molecularly imprinted PPy/pABSA. To avoid the interference from the oxidation peak of PPy on the following electrochemical chiral recognition of Trp isomers, PPy was overoxidized by cyclic voltammetry (CV). The resultant molecularly imprinted overoxidized PPy (OPPy)/pABSA modified GCE exhibits higher affinity toward l‐Trp than d‐tryptophan (d‐Trp); that is, the oxidation peak current of l‐Trp is greatly higher than that of d‐Trp at the molecularly imprinted OPPy/pABSA modified GCE. [ABSTRACT FROM AUTHOR]

To explore the relationship between autophagy and cell function, we investigated how PLAC8‐mediated autophagy influences proliferation, apoptosis and epithelial‐mesenchymal transition (EMT) in NPC. Colony formation analyses and CCK8 assays were used to assess the proliferative capacity of NPC cells. Transmission electron microscopy (TEM) was used to identify autophagosomes. Autophagic flux was monitored using the tandem monomeric RFP‐GFP‐tagged LC3 (tfLC3) assay. The rate of apoptosis in NPC cells was analysed by flow cytometry. Western blot analysis was used to evaluate the activation of autophagy and the signalling status of the AKT/mTOR pathway. Our study reveals that knocking out PLAC8 (koPLAC8) induces autophagy and apoptosis, while suppressing NPC cell proliferation and EMT. However, inhibition of autophagy with 3‐methyladenine or by knocking down Beclin‐1 reverses the cell proliferation, apoptosis and EMT influenced by koPLAC8. We find that koPLAC8 inhibits the phosphorylation of AKT and its downstream target, mTOR. Moreover, immunofluorescence and co‐immunoprecipitation reveal complete PLAC8/AKT colocalization and PLAC8/AKT interaction, respectively. Furthermore, knockout of PLAC8 induced autophagy and inactivated AKT/mTOR signalling pathway of NPC xenografts. Overall, our findings demonstrate that koPLAC8 induces autophagy via the AKT/mTOR pathway, thereby inhibiting cell proliferation and EMT, and promoting apoptosis in NPC cells. [ABSTRACT FROM AUTHOR]

A novel composite of graphene quantum dots functionalized Sb2WO6 (GQDs/Sb2WO6) was prepared by an electrostatic self‐assembly method and used as a photocatalyst for the degradation of an organic pollutant. The resulting GQDs/Sb2WO6 was characterized by electron microscopy and optical measurements. The photocatalytic activity of GQDs/Sb2WO6 was investigated by degrading methyl orange (MO) under UV‐light and visible‐light irradiation. Compared with pure Sb2WO6, enhancement of the photocatalytic performance of GQDs/Sb2WO6 was achieved, and the degradation efficiency for MO was almost 100% within 3 h under UV‐light irradiation and 71.4% within 3 h under visible‐light irradiation. The photocatalytic degradation mechanism of GQDs/Sb2WO6 was illustrated by free radical and hole scavenging experiments, and the main active species were confirmed to be holes (h+) and superoxide anion radicals (O2·−). Moreover, the GQDs/Sb2WO6 composites exhibited high recyclability and stability and had potential application for decomposing other organic contaminants in water. [ABSTRACT FROM AUTHOR]

Guanidinocalix[5]arene and fluorescein reporter pair has been chosen to set up a supramolecular tandem assay principle based on the differential recognition of pyridoxal‐5′‐phosphate (the substrate of alkaline phosphatase, ALP), pyridoxal (the product of ALP) and phosphate (the product of ALP). This supramolecular tandem assay system offers an opportunity to monitor the activity of ALP in a label‐free, continuous, and real‐time manner. More importantly, a calibration curve can be given for selective and quantitative detection of pyridoxal‐5′‐phosphate (biomarker for several diseases). [ABSTRACT FROM AUTHOR]

A three‐dimensional molecularly imprinted overoxidized polypyrrole/MnO2/carbon felt (MIOPPy/MnO2/CF) composites were fabricated, which results in increased active area of the surface of the molecularly imprinted polymers film and greatly improved electrochemical chiral recognition effect for tryptophan isomers. The composites were characterized by field emission scanning electron microscope, transmission electron microscope, X‐ray diffractometer, UV‐visible spectra, N2 adsorption‐desorption isotherms, and electrochemical methods. The manuscript provides a proof of concept and shows promising potential of the prepared composites for chiral recognition. [ABSTRACT FROM AUTHOR]

Due to the outstanding light-thermal conversion behavior of the SiO SB 2 sb @PPy@mSiO SB 2 sb , a NIR light-controlled drug delivery system is constructed based on the SiO SB 2 sb @PPy@mSiO SB 2 sb and thermosensitive PEG-PCL-PEG copolymer. On the contrary, the PEG-PCL-PEG copolymers will retain their hydrogel phase without NIR irradiation and the drug molecules can still be well encapsulated within the SiO SB 2 sb @PPy@mSiO SB 2 sb , leading to negligible release of 5-FU. In other words, both the excellent light-thermal conversion efficiency of nano PPy in the SiO SB 2 sb @PPy@mSiO SB 2 sb and the thermosensitive gel-sol transition behavior of the PEG-PCL-PEG hydrogel contribute to the sustained release of the drug. The results reveal that both the excellent light-thermal conversion efficiency of the nano PPy in the SiO SB 2 sb @PPy@mSiO SB 2 sb and the thermosensitive gel-sol transition behavior of the PEG-PCL-PEG hydrogel contribute to the sustained release of 5-FU. [Extracted from the article]

A palladium‐catalyzed inert C−H bond activation and cyclocarbonylation of isoquinolones leading to isoindolo[2,1‐b]isoquinoline‐5,7‐diones under 1 atm of carbon dioxide has been developed. This transformation features high regio‐ and chemo‐selectivity, step‐economy, and good functional group tolerance. Most of the corresponding products were obtained in moderate to good yields. It offers an alternative approach for the synthesis of useful diverse isoindolo[2,1‐b]isoquinoline‐5,7‐dione derivatives. [ABSTRACT FROM AUTHOR]

Iridium‐catalyzed C−H activation and cyclization of naphthalen‐1‐amines with diazo compounds leading to naphtho[1,8‐bc]pyridines have been developed. Different from the previous free‐amine‐directed C−H functionalization with diazo compounds that relied on the coordination of lone pair electrons or in situ formation of imine, this transformation passes through a five‐membered iridacycle intermediate containing an N−Ir σ‐bond. It offers an alternative approach for the synthesis of useful diverse naphtho[1,8‐bc]pyridine derivatives in mild conditions. [ABSTRACT FROM AUTHOR]

A 3D printing methodology for the design, optimization, and fabrication of a custom nerve repair technology for the regeneration of complex peripheral nerve injuries containing bifurcating sensory and motor nerve pathways is introduced. The custom scaffolds are deterministically fabricated via a microextrusion printing principle using 3D models, which are reverse engineered from patient anatomies by 3D scanning. The bifurcating pathways are augmented with 3D printed biomimetic physical cues (microgrooves) and path-specific biochemical cues (spatially controlled multicomponent gradients). In vitro studies reveal that 3D printed physical and biochemical cues provide axonal guidance and chemotractant/chemokinetic functionality. In vivo studies examining the regeneration of bifurcated injuries across a 10 mm complex nerve gap in rats showed that the 3D printed scaffolds achieved successful regeneration of complex nerve injuries, resulting in enhanced functional return of the regenerated nerve. This approach suggests the potential of 3D printing toward advancing tissue regeneration in terms of: (1) the customization of scaffold geometries to match inherent tissue anatomies; (2) the integration of biomanufacturing approaches with computational modeling for design, analysis, and optimization; and (3) the enhancement of device properties with spatially controlled physical and biochemical functionalities, all enabled by the same 3D printing process. [ABSTRACT FROM AUTHOR]

A novel electrochemical sensor based on Ag nanoparticles (AgNPs) decorated polyaniline/graphene composites (PANI/G) is developed, which can be used for sensitive determination of H2O2. For the construction of the H2O2 sensor, polyaniline (PANI) is first electrodeposited on the surface of graphene (G) to form PANI/G, and then horseradish peroxidase (HRP) loaded on AgNPs (HRP/AgNPs) is immobilized on to the PANI/G. H2O2 can be catalyzed by HRP to generate current response which can be significantly enhanced by AgNPs, and thus the PANI/G based sensor can be utilized for the detection of H2O2. Under the optimized conditions, the proposed H2O2 sensor exhibits wide linear response to H2O2 concentration ranging from 0.25 to 2.25 mM with a detection limit of 0.03 mM (signal-to-noise ratio of 3), and it also shows high selectivity and reproducibility. The method is simple and costeffective, and can be a promising candidate as the sensitive sensing platform for H2O2. [ABSTRACT FROM AUTHOR]

ABSTRACT Poly(aniline- co-o-aminophenol) (PANOA) was synthesized via electrochemical copolymerization of o-aminophenol and aniline using p-toluene sulfonate (TSA−) as the counterion. The redox transformation of PANOA is accompanied by the exchange of anions into and out of the copolymer, and the feasibility of perchlorate (ClO4−) removal via an electrically switched ion exchange process was evaluated in this study. The results of electrochemical quartz crystal microbalance (EQCM), electrochemical impedance spectroscopy (EIS), and Fourier transform infrared spectroscopy (FTIR) demonstrated the successful release of TSA− upon reduction and uptake of ClO4− upon reoxidation of the copolymer. Also, in this work, the possible ion-exchange mechanism of PANOA was proposed. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41895. [ABSTRACT FROM AUTHOR]

Background Processed umbilical cord blood ( UCB) must be stored at cryogenic temperature at all times to maintain the quality and viability of the cells. However, a challenge is presented in the form of moving a large number of cryopreserved UCB samples to a new location. In this report, we share our experience on relocating more than 100,000 units of cryopreserved UCB samples stored in 12 liquid nitrogen freezers ( LNFs) to our new laboratory. Study Design and Methods For quality control purposes, 2 weeks before relocation, donor UCB samples were processed, cryopreserved, and stored in each LNF. On relocation day, half of the samples were retrieved to determine total nucleated cell count, percentage of CD34+ cells, and cell viability as controls for later comparison. UCB samples were transferred into dry shippers before being relocated to the new laboratory. Upon arrival, LNFs were serviced before transferring UCB samples back into its original location within the LNF. The remaining donor UCB samples were retrieved and analyzed for the same tests mentioned. Results We found no significant differences in pre- and postrelocation values of the tests performed. Conclusion All UCB samples were successfully relocated into the new laboratory without affecting the quality. [ABSTRACT FROM AUTHOR]

The attapulgite/carbon (ATP/C) nanocomposite was successfully prepared by two ecofriendly raw materials (ATP, which is a hydrated magnesium aluminum silicate widespread in nature, and d-xylose, which can be obtained from rice hull, wheat straw, etc.) through a facile one-pot hydrothermal procedure. The synthesis conditions, including reaction time, hydrothermal temperature, and the concentration of d-xylose, were regulated to investigate the morphology, functional groups, and pore properties of ATP/C. Adsorption experiments demonstrated that the obtained ATP/C materials had great potential in treatment of methylene blue from aqueous solution. A possible formation mechanism of ATP/C nanocomposite was proposed by powder X-ray diffraction, TG analysis, and N2 adsorption-desorption study, which revealed that carbon successfully anchored onto ATP by the chemical bond of SiOC. © 2014 American Institute of Chemical Engineers Environ Prog, 34: 437-444, 2015 [ABSTRACT FROM AUTHOR]

ABSTRACT A compact fourth-order six-stages split-step finite-difference time-domain method is developed, which is based on the compact fourth-order scheme. The proposed method improves the efficiency of computation by reducing the bandwidth of the matrix to be inversed from seven to five for the fourth-order scheme. Furthermore, the proposed method is proven to be unconditionally stable. The numerical dispersion error of this new approach is studied by comparison to the original second-order method and fourth-order method. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1031-1036, 2014 [ABSTRACT FROM AUTHOR]

Titanium dioxide/palygorskite (TiO2/PA) was prepared by acid-catalyzed sol-gel method and the resulting composite was applied in the adsorption of anion dye, Congo red. The effects of various experimental parameters such as adsorbent dosage, contact time and initial dye concentration on adsorption were investigated in detail. The adsorption behaviors of TiO2/PA composite showed that the adsorption kinetics and isotherms were in good agreement with the pseudo-second-order equation and the Langmuir model, respectively. And the maximum adsorption capacity of TiO2/PA composite for Congo red calculated by the Langmuir model was 518.13 mg g−1. Unlike conventional research on TiO2-based material, in which TiO2 was utilized as the photocatalyst for wastewater treatment. Here, the removal of Congo red was mainly due to the excellent adsorption capacity of PA and amorphous TiO2. So the TiO2/PA composite could be a promising adsorbent for anion dyes adsorption. © 2012 American Institute of Chemical Engineers Environ Prog, 32: 1090-1095, 2013 [ABSTRACT FROM AUTHOR]

Modified palygorskite-polythiophene (MPA-PTh) composites were prepared by chemical oxidative polymerization of palygorskite (PA) nucleartor with thiophene (Th) after the surface modification with γ-(2,3-epoxypropoxy) propytrimethoxysilane (KH-560). The MPA-PTh composites were doped in iodine vapor to create the porous palygorskite-polythiophene (PMPA-PTh) conductive composites. Fourier transform infrared spectra (FTIR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), N2 adsorption-desorption isotherms using the Brunauer-Emmett-Teller method (BET) and electrochemical impedance spectrum (EIS) techniques were applied to characterize the modified PA and the prepared composites. According to FTIR and XPS, the KH-560 was bound to the PA surface and the iodine ion (I3− and I5−) entered the PTh molecular chains. XRD, SEM, TEM, BET, and EIS analysis confirmed that the doping of iodine not only transform the core-shell MPA-PTh into the PMPA-PTh but also improve the electrical conductivity of composites. The PMPA-PTh composites were fabricated that yield a volume resistivity of ∼2.44 × 102 Ω cm and a internal resistances of ∼100 Ω, and their BET surface area, BJH (Barrett-Joiner-Halenda) average pore size and BJH cumulative pore volume were improved in comparison with those of the MPA-PTh composites. SEM images showed that the PMPA-PTh composites could form consecutive space network and the PMPA-PTh composites acrylic coating films had advisable conductivity. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]

A novel strategy is developed for the fabrication of graphene-CdS (G-CdS) nanocomposites by in situ growth of CdS nanoparticles onto simultaneously reduced graphite oxide, which is noncovalently functionalized by sodium 1-pyrene sulfonate through strong π-π stacking interactions. Subsequently, cobalt 2,9,16,23-tetraaminophthalocyanine (CoTAPc) is self-assembled on the G-CdS nanocomposites through electrostatic interactions to produce phthalocyanine-sensitized G-CdS nanocomposites. The photoactive superstructure enhances the photocurrent generation capability, and presents an efficient photoelectrochemical immunosensing platform for the ultrasensitive detection of the prostate-specific antigen (PSA). The quantitative measurement of PSA is based on the decrease in the photocurrent intensity of the phthalocyanine-sensitized G-CdS nanocomposites, which results from an increase in the steric hindrance due to the formation of the immunocomplex. A linear relationship between the photocurrent decrease and the PSA concentration is obtained in the wide range from 1 pg mL−1 to 5 μg mL−1 with a detection limit of 0.63 pg mL−1. The proposed sensor shows high sensitivity, stability, reproducibility, and can become a promising platform for other biomolecular detection. [ABSTRACT FROM AUTHOR]

A series of o-aryloxide-N-heterocyclic carbene ruthenium complexes 2-4 is synthesized via sequential reactions of the o-hydroxyaryl imidazolium proligands (2-OH-3,5- tBu2C6H2)(R)(C3H3N2)+Br− (R = Me ( 1a), iPr ( 1b), Mes ( 1c)) with Ag2O and [(C6H6)RuCl2]2. All of the complexes are characterized by 1H and 13C NMR spectroscopy, high-resolution mass spectrometry (HRMS), and elemental analysis. The molecular structure of 2 is determined by single-crystal X-ray diffraction analysis. The ring-opening metathesis polymerization (ROMP) of norbornene (NBE) with 2- 4 is studied. Among them, complex 4 exhibits the highest activity and efficiency toward ROMP of NBE at 85 °C without any cocatalyst, and the resultant polymers have very high molecular weight (>106 Da) and narrow molecular weight distributions. This complex can also efficiently catalyze the alternating copolymerization of NBE and cyclooctene. [ABSTRACT FROM AUTHOR]

A polypyrrole (PPy)-flake graphite composite was synthesized by in situ polymerization of pyrrole on flake graphite surface, and the resulting organic-inorganic composite material was developed as the conductive stationary phase in an electrode column for enantioselective recognition of tryptophan (Trp) enantiomers. Compared with the stationary phase made up with conducting PPy, the conductivity of the composite stationary phase was enhanced significantly. As a result, satisfactory enantioselectivity of Trp enantiomers can be achieved easily by modulating the potential applied on the electrode column. Various important parameters influencing the performance of the composite electrode column were investigated to obtain the optimum recognition efficiency. A recognition efficiency of 3.7 could be achieved under the optimum conditions. Enantioselectivity of the composite material for Trp enantiomers is attributed to the reversible doping/de-doping properties of PPy. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 [ABSTRACT FROM AUTHOR]

The article discusses a study that investigated the adsorption conditions of copper (Cu)(II), nickel (Ni)(II), cadmium (Cd)(II), and chromium (Cr)(II) from single-metal solutions using a polyaniline/polygorskite (PP) composite. The structural characteristic of the composite are evaluated. Findings prove the potential use of the novel organic/inorganic composite in the recovery and elimination of noble or heavy metal ions form industrial wastewater.

The article discusses a study on synthesizing and characterizing isomeric poly(ether ether ketone)s. Microwave-assisted method by nucleophilic substitution reaction of hydroquinone and 4,4'-biphenol with 4,4'-difluorobensophenone (DFBP) or 2,4'-DFBP in the presence of anhydrous K2CO3 was employed in the study. It was found that the reaction time was shortened and the reaction temperature could be controlled easily.

To study allele‐specific expression (ASE) and binding (ASB), that is, differences between the maternally and paternally derived alleles, we have developed a computational pipeline (AlleleSeq). Our pipeline initially constructs a diploid personal genome sequence (and corresponding personalized gene annotation) using genomic sequence variants (SNPs, indels, and structural variants), and then identifies allele‐specific events with significant differences in the number of mapped reads between maternal and paternal alleles. There are many technical challenges in the construction and alignment of reads to a personal diploid genome sequence that we address, for example, bias of reads mapping to the reference allele. We have applied AlleleSeq to variation data for NA12878 from the 1000 Genomes Project as well as matched, deeply sequenced RNA‐Seq and ChIP‐Seq data sets generated for this purpose. In addition to observing fairly widespread allele‐specific behavior within individual functional genomic data sets (including results consistent with X‐chromosome inactivation), we can study the interaction between ASE and ASB. Furthermore, we investigate the coordination between ASE and ASB from multiple transcription factors events using a regulatory network framework. Correlation analyses and network motifs show mostly coordinated ASB and ASE. [ABSTRACT FROM AUTHOR]

The article focuses on a study which examined the electrosynthesis of polypyrrole with L-trytophan (L-Trp) as a template to prepare molecularly imprinted polymers (MIPs). It notes that electropolymerization potential, overoxidization potential and time, and polypyrrole film thickness as some of the key parameters studied. Results of the study showed that cavities in the imprinted films influence the enantioselectivity of the MIPs.

Ruthenium catalysts supported on multiwalled carbon nanotubes (MCNTs) with different loadings (1% wt, 3% wt, 5% wt) were prepared by reduction with H2 or NaBH4 for selective hydrogenation of soybean oil at 338 K and initial pressure of 1.066 MPa. These catalysts were characterized using transmission electron microscopy (TEM), X-ray powder diffraction (XRD), N2 adsorption–desorption, and H2-temperature programmed desorption (TPD) techniques. Ru particles were dispersed more homogeneously on the surface of the nanotubes after being reduced with H2 than with NaBH4. The catalysts with 3% and 5% Ru loadings had higher hydrogenation activity. The NaBH4-reduced catalyst had higher cis-isomer selectivity. [ABSTRACT FROM AUTHOR]

The article reports on the metallization of copper (Cu) on to surface-modified polyimide resin. The method involves potassium hydroxide-induced modification of the polyimide surface to introduce carboxylic acid groups and incorporation of gold colloids as a seed layer. Gold colloids serves as a conductive layer to catalyze the electroless plating of Cu on polyimide surface. The potential of such procedure in the manufacturing of Cu circuit patterns in the microelectronic industry is suggested.

A new split-step finite difference time domain (SS-FDTD) method with high-order accuracy is presented, which is proven to be unconditionally stable and has four substeps. The numerical dispersion error and the numerical anisotropic error of the proposed method are reduced than the alternating direction implicit finite difference time domain method, the conventional SS-FDTD method and the SS-FDTD method based on the Strang-splitting scheme. The proposed method has new splitting forms, which is different from the SS-FDTD method based on the exponential evolution operator. At each time step, an important aspect is that the proposed method produces 33% reduction of the total number of arithmetic operators than the SS-FDTD method based on the exponential evolution operator. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 562–565, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24100 [ABSTRACT FROM AUTHOR]

Four Ru nanoparticles of different mean sizes from 1.13 to 17.22 nm were prepared and used as catalysts for the selective hydrogenation of polyunsaturated soybean oil at 353 K and initial pressure of 1.5 MPa. The catalyst with the smallest mean size (1.13 nm) had the lowest activity, the activity increased as the mean size increased to 3.10 nm, then decreased with further increase in the mean particle size. The cis-trans isomerization rate decreased with the increase in particle size. [ABSTRACT FROM AUTHOR]