Improving Biocatalytic Synthesis of Furfuryl Alcohol by Effective Conversion of D-Xylose into Furfural with Tin-Loaded Sulfonated Carbon Nanotube in Cyclopentylmethyl Ether-Water Media

Catalysis Letters - Carbon nanotube (CNT) was utilized as as the precursor to synthesize solid acid (tin-loaded sulfonated carbon nanotube, SO42?/SnO2-CNT) for catalyzing D-xylose into...     

Effect of boron oxide on mechanical and thermal properties of bioactive glass coatings for biomedical applications

Bioactive glass coatings can improve the osteo integration of metallic implants with the host tissue, thereby increasing their lifespan and overall success rate. However, complex composition-structure-property relations in phosphosilicate-based bioactive glasses make experimental determination of these relations and related composition design of bioactive coatings challenging. By applying molecular dynamics (MD)-based atomistic simulations with recently developed effective potentials, this work addresses the challenge by using a material genome approach to obtain the composition and structure effects on various key properties for bioactive coating applications. A series of potential bioactive glass compositions were studied and the composition effects on the mechanical and thermal properties that are critical to these bioactive glasses as a coating to metallic implants were calculated. Particularly, by varying the level of B₂O₃ to SiO₂ substitutions, the effect of composition on various key properties was elucidated. It was found that by using cation in a 1 to 1 ratio (BO_3/2 to SiO₂) instead of the commonly used substitutions (B₂O₃ to SiO₂), the composition effect can be more clearly expressed and, hence, recommended in future composition designs. Together with careful structural analysis, the origin of property changes can be elucidated. The atomistic computer simulation-based approach is, thus, an effective way to guide future bioactive glass designs for bioactive coatings and other applications.     

Cross-Talk among Polymorphonuclear Neutrophils,Immune, and Non-Immune Cells via Released Cytokines,Granule Proteins,Microvesicles, and Neutrophil Extracellular Trap Formation: A Novel Concept of Biology and Pathobiology for Neutrophils

Polymorphonuclear neutrophils (PMNs) are traditionally regarded as professional phagocytic and acute inflammatory cells that engulf the microbial pathogens. However, accumulating data have suggested that PMNs are multi-potential cells exhibiting many important biological functions in addition to phagocytosis. These newly found novel activities of PMN include production of different kinds of cytokines/chemokines/growth factors, release of neutrophil extracellular traps (NET)/ectosomes/exosomes and trogocytosis (membrane exchange) with neighboring cells for modulating innate, and adaptive immune responses. Besides, PMNs exhibit potential heterogeneity and plasticity in involving antibody-dependent cellular cytotoxicity (ADCC), cancer immunity, autoimmunity, inflammatory rheumatic diseases, and cardiovascular diseases. Interestingly, PMNs may also play a role in ameliorating inflammatory reaction and wound healing by a subset of PMN myeloid-derived suppressor cells (PMN-MDSC). Furthermore, PMNs can interact with other non-immune cells including platelets, epithelial and endothelial cells to link hemostasis, mucosal inflammation, and atherogenesis. The release of low-density granulocytes (LDG) from bone marrow initiates systemic autoimmune reaction in systemic lupus erythematosus (SLE). In clinical application, identification of certain PMN phenotypes may become prognostic factors for severe traumatic patients. In the present review, we will discuss these newly discovered biological and pathobiological functions of the PMNs.     

Robust fault estimation based on learning observer for Takagi-Sugeno fuzzy systems with interval time-varying delay

This paper studies the problem of robust fault estimation for a class of Takagi-Sugeno(T-S) fuzzy systems which subject to interval time-varying delay, external disturbance, and actuator fault. The designed learning observer can achieve simultaneous estimation of system state and time-varying or constant actuator fault. Then, we construct a new Lyapunov-Krasovskii functional including the information of the lower and upper delay bounds; compared with the time-varying delay, the interval time-varying delay is the less conservative form. Furthermore, one less conservative delay-dependent condition for the existence of learning observer is given in terms of linear matrix inequalities. In addition, the results for the systems with interval time-varying delay are simplified when the delay is not concluded. Finally, simulation results of two examples are presented to show the effectiveness of the proposed method.     

Effective disinfection of airborne microbial contamination in hospital wards using a zero‐valent nano‐silver/TiO2‐chitosan composite

A novel antimicrobial composite of zero‐valent silver nanoparticles (AgNPs), titania (TiO₂), and chitosan (CS) was prepared via photochemical deposition of AgNPs on a CS‐TiO₂ matrix (AgNPs@CS‐TiO₂). Electron microscopy showed that the AgNPs were well dispersed on the CS‐TiO₂, with diameters of 6.69‐8.84 nm. X‐ray photoelectron spectra indicated that most of the AgNPs were reduced to metallic Ag. Fourier‐transform infrared spectroscopy indicated that some AgNPs formed a chelate with CS through coordination of Ag⁺ with the CS amide II groups. The zones of inhibition of AgNPs@CS‐TiO₂ for bacteria (Escherichia coli and Staphylococcus epidermidis) and fungi (Aspergillus niger and Penicillium spinulosum) were 6.72‐11.08 and 5.45‐5.77 mm, respectively, and the minimum (critical) concentrations of AgNPs required to inhibit the growth of bacteria and fungi were 7.57 and 16.51 µg‐Ag/mm², respectively. The removal efficiency of a AgNPs@TiO₂‐CS bed filter for bioaerosols (η) increased with the packing depth, and the optimal filter quality (qF) occurred for packing depths of 2‐4 cm (qF = 0.0285‐0.103 Pa^?1; η = 57.6%‐98.2%). When AgNPs@TiO₂‐CS bed filters were installed in the ventilation systems of hospital wards, up to 88% of bacteria and 97% of fungi were removed within 30 minutes. Consequently, AgNPs@TiO₂‐CS has promising potentials in bioaerosol purification.     

Two-dimensional analysis of a BiNMOS transistor operating at 77 Kusing a modified PISCES program

The authors present a detailed two-dimensional numerical simulation study on the steady-state and turn-on transient behavior of a BiNMOS device operating at 77 K using PISCES-2B with modified low-temperature models. It is shown that the switching speed of the BiNMOS device, which is designed for operation at room temperature, is degraded for low-temperature operation. The BiNMOS device structure and the low-temperature device models for the two-dimensional (2D) device simulator are described, following by the steady-state and the transient analysis of the BiNMOS device. The turn-on transient performance of the BiNMOS device shows that, at 77 K, the switching time, which is determined by the load-related delay and the intrinsic delay of the bipolar device, increases about 45% from its 300 K value for an output load of 0.1 pF/μm     

Batch fabrication and structure of integrated GaAs-AlxGa1-xAs field-effect transistor-self-electro-optic effectdevices (FET-SEED's)

The authors have demonstrated a smart pixel prototype field-effect-transistor-self-electrooptic-effect-device (FET-SEED) integrated optoelectronic amplifier utilizing process technology suitable for flexible design and fabrication of high-yield optoelectronic circuits. A single MBE growth sequence provides for quantum-well modulators, photodiodes, doped channel MIS-like field-effect transistors (DMTs), and resistors. The device dimensions are controlled in a planar technology using ion implantation and selective plasma etching for isolation and contacting. Results demonstrate optical amplification in a fully integrated circuit. This technology will enable increased functionality by providing digital electronic processing between optical input and output     

Chaos and its computing paradigm

Recently, there has been interest in so-called alternative computing paradigms that differ from traditional silicon-based computing architectures. One such alternative is chaos computing which exploits the inherent dynamics of chaotic systems. Chaos has three defining characteristics: (i) sensitivity to initial conditions, (ii) aperiodic long-term behavior, (iii) wholly deterministic. Since research in chaos computing is only in its infancy it is as yet not appropriate to debate the optimality of computing using chaos. However, unlike other alternative computing paradigms such as DNA computing and quantum computing, chaos computing presents a framework which one day might be appropriate for a general purpose machine.     

The effects of accumulated experience on radiofrequency ablation of accessory pathways

Increasing experience in radiofrequency ablation for accessory pathways appears to reduce the procedure time, radiation time and radiofrequency pulse number, and results in a higher success rate. However, the effect of a learning curve on this procedure from the perspective of location and conduction direction of accessory pathways has not been reported before. The purpose of this study was to determine the effect of accumulated experience on the outcomes of radiofrequency ablation for accessory pathways and on the duration of the procedure parameters by analyzing the results of a dedicated ablation team. The first 512 patients with a single accessory pathway treated in this laboratory were included for analysis of the procedure parameters with respect to locations and conduction directions of accessory pathways. The results showed that the average procedure time, radiation time, and radiofrequency pulse number differed significantly among the different subgroups (left free wall, right free wall, posteroseptal and anteromidseptal location; manifest or concealed conduction). All subgroups except the anteromidseptal pathways showed a significant improvement of the procedure parameters with increased ablation experience. Although the initial rate of improvement was similar among the different subgroups, the rate of improvement in left free wall pathways nearly reached a plateau after 120 ablation procedures. Thus it was concluded that a certain number of ablation procedures was necessary before achievement of a high success rate with shorter procedure and radiation times and a lower radiofrequency pulse number.