Petri Net modelling approach for analysing the behaviour of Wnt/ β ‐catenin and Wnt/ Ca2+ signalling pathways in arrhythmogenic right ventricular cardiomyopathy

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited heart muscle disease that may result in arrhythmia, heart failure and sudden death. The hallmark pathological findings are progressive myocyte loss and fibro fatty replacement, with a predilection for the right ventricle. This study focuses on the adipose tissue formation in cardiomyocyte by considering the signal transduction pathways including Wnt/ β ‐catenin and Wnt/Ca²⁺ regulation system. These pathways are modelled and analysed using stochastic petri nets (SPN) in order to increase our comprehension of ARVC and in turn its treatment regimen. The Wnt/ β ‐catenin model predicts that the dysregulation or absence of Wnt signalling, inhibition of dishevelled and elevation of glycogen synthase kinase 3 along with casein kinase I are key cytotoxic events resulting in apoptosis. Moreover, the Wnt/Ca²⁺ SPN model demonstrates that the Bcl2 gene inhibited by c‐Jun N‐terminal kinase protein in the event of endoplasmic reticulum stress due to action potential and increased amount of intracellular Ca²⁺ which recovers the Ca²⁺ homeostasis by phospholipase C, this event positively regulates the Bcl2 to suppress the mitochondrial apoptosis which causes ARVC.Inspec keywords: molecular biophysics, enzymes, cancer, muscle, Petri nets, cellular biophysics, bioelectric potentials, biomembranes, tumours, cardiology, genetics, biochemistry, calciumOther keywords: heart failure, sudden death, hallmark pathological findings, progressive myocyte loss, fibro fatty replacement, adipose tissue formation, signal transduction pathways, Ca²⁺ regulation system, stochastic petri nets, ARVC, $β‐catenin model, Wnt signalling, glycogen synthase kinase 3, Bcl2 gene, c‐Jun N‐terminal kinase protein, petri Net modelling approach, Ca²⁺ signalling pathways, arrhythmogenic right ventricular cardiomyopathy, inherited heart muscle disease, Ca²⁺ SPN model, Ca     

Calibration of ultrahigh vacuum gauge from 10 Pa to 10 Pa by the two-stage flow-dividing system

A new two-stage flow-dividing system has been developed for the calibration of ultrahigh vacuum gauges from 10⁻⁹ Pa to 10⁻⁵ Pa for N₂, Ar, and H₂. This system is designed based on the techniques for our previously developed calibration system in the range from 10⁻⁷ Pa to 10⁻² Pa. Three modifications were performed to extend the calibration pressure to a lower range. The relative standard uncertainty of the generated pressure (k = 1) is in the range from 2.3% to 2.6%, from 10⁻⁹ Pa to 10⁻⁵ Pa. The characteristics of ultrahigh vacuum gauges were also examined by using this system. The stabilities of the pressure reading, the linearity, the temperature dependence, and the long-term stability were examined. These results show that the calibration of ultrahigh vacuum gauges is possible in the range from 10⁻⁹ Pa to 10⁻⁵ Pa for N₂, Ar, and H₂ with the uncertainty of about 6.0% (k = 2) by this new system.     

Development of a lightweight low-current 10 K 4 T magnet for space-flight ADRs

Future space missions will include detectors and other components cooled to cryogenic temperatures by adiabatic demagnetization refrigerators (ADRs) coupled with mechanical cryocoolers. In such systems the ADRs require lightweight, low-current superconducting magnets. At least one of an ADR’s magnets must operate at the cryocooler’s coldest stage temperature. This temperature should be as high as possible in order to improve operating efficiency and design flexibility. We previously reported the development of a lightweight (1 kg) low-current (8 A) Nb₃Sn magnet which produces a 3 T central field at 10 K. We now report our progress in developing a new 10 K magnet of similar size made with smaller diameter Nb₃Sn wire which will produce a 4 T central field with approximately 5 A.     

Biofabrication of nanogold from the flower extracts of Lantana camara

The present investigation was done to explore the potential of Lantana camara (L. camara) flower in the fabrication of gold nanoparticles (AuNPs). The shape and size of AuNPs have been successfully controlled by introducing small amounts of L. camara flower extract. It produced spherical nanogold of average size 10.6 ± 2.9 nm without any aggregation and showed significant photocatalytic degradation activity of the methylene blue (>62%, 10 mg/L) in the presence of solar light. In addition, the experimental approach is inexpensive, rapid and eco‐friendly for industrial scale production of nanoparticles.Inspec keywords: nanoparticles, gold, nanofabrication, botany, catalysis, photochemistry, organic compoundsOther keywords: biofabrication, Lantana camara flower extract, gold nanoparticles fabrication, spherical nanogold, photocatalytic degradation activity, methylene blue, solar light, size 10.6 nm to 2.9 nm, Au     

Rapid synthesis of Bi 2 O 3 nano‐needles via ‘green route’ and evaluation of its anti‐fungal activity

Here, the authors report a rapid, simple, and eco‐friendly process for synthesis of Bi₂ O₃ nano‐needles. Dioscorea alata tuber extract was used as both reducing and capping agent for the first time. These nanoparticles were characterised by X‐ray diffraction, field emission scanning electron microscope, and Fourier transform infrared (FTIR) spectrometry, the nano‐structured Bi₂ O₃ needles have an average diameter of 158 nm with the lengths in the range of 1–3 μm. CLSI M27‐A2 standard was followed for evaluation of anti‐fungal activity. Bi₂ O₃ nano‐needles show remarkable activity against Candida albicans. It exhibits four time greater activity than bulk Bi₂ O₃ powder and two time greater activity than itraconazole, which makes it a potent anti‐fungal drug.Inspec keywords: bismuth compounds, nanoparticles, X‐ray diffraction, field emission scanning electron microscopy, Fourier transform infrared spectra, drugs, nanomedicine, biomedical materials, nanofabricationOther keywords: nanoneedles, antifungal activity, nanoparticles, X‐ray diffraction, field emission scanning electron microscope, Fourier transform infrared spectrometry, CLSI M27‐A2 standard, Candida albicans, itraconazole, antifungal drug, Bi₂ O₃      

Comparative antileishmanial efficacy of the biosynthesised ZnO NPs from genus Verbena

This study describes ZnO NPs biosynthesis using leaf extracts of Verbena officinalis and Verbena tenuisecta. The extracts serve as natural reducing, capping and stabilization facilitators. Plant extracts phytochemical analysis, revealed that V. officinalis showed higher total phenolic and flavonoid content (22.12 and 6.38 mg g ⁻¹ DW) as compared to V. tennuisecta (12.18 and 2.7 mg g ⁻¹ DW). ZnO NPs were characterised by ultraviolet–visible spectroscopy, Fourier transform infrared, X‐ray diffraction, scanning electron microscope, transmission electron microscopy (TEM) and energy dispersive X‐ray. TEM analysis of ZnO NPs reveals rod and flower shapes and were in the range of 65–75 and 14–31 nm, for V. tenuisecta and V. officinalis, respectively. Bio‐potential of ZnO NPs was examined through their leishmanicidal potential against Leishmania tropica. ZnO NPs showed potent leishmanicidal activity with 250 µg ml⁻¹ being the most potent concentration. V. officinalis mediated ZnO NPs showed more potent leishmanicidal activity compared to V. tenuisecta mediated ZnO NPs due to their smaller size and increased phenolics doped onto its surface. These results can be a step forward towards the development of novel compounds that can efficiently replace the current medication schemes for leishmaniasis treatment.Inspec keywords: ultraviolet spectra, nanomedicine, nanostructured materials, visible spectra, X‐ray diffraction, antibacterial activity, nanoparticles, zinc compounds, scanning electron microscopy, microorganisms, nanofabrication, drugs, transmission electron microscopy, X‐ray chemical analysis, health and safety, particle size, renewable materials, diseases, Fourier transform infrared spectraOther keywords: flavonoid content, natural reducing stabilisation facilitators, ZnO nanoparticles synthesis, antileishmanial efficacy, Verbena tennuisecta, Verbena officinales, phytochemical analysis, phenolic content, ultraviolet–visible spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscopy, X‐ray diffraction, transmission electron microscopy, energy dispersive X‐ray analysis, particle size, leishmaniasis treatment, leaf extracts, medication scheme, stabilisation facilitator, capping facilitator, size 14.0 nm to 31.0 nm, size 65.0 nm to 75.0 nm, ZnO     

Development and operation of a high performance 10kw absorption chillerDéveloppement et fonctionnement d''un refroidisseur haute performance à absorption d''une capacité de 10 kW

This paper describes the development and operation of a rotating double effect absorption chiller, which uses an aqueous solution of mixed metal hydroxides as the absorbent. The design principles are outlined including the operation of the major components and the ways in which the integration of the processes has been achieved. The operation of the fluid management system is described. Experimental performance data are presented from laboratory testing for the machine operating as a chiller.     

基于再生基础油的CF-4 10W/30柴油机油的研制

废机油在预处理后,采用分子蒸馏设备对其进行了蒸馏分离,得到的轻组分再进行加氢精制,生成再生润滑油。元素分析显示精制前后硫含量下降约66.3%。以再生润滑油与68#机械油调和成再生基础油,作为柴油机油的基础油。实验结果表明,再生基础油的抗磨性较好,这与再生基础油中残存的少量抗磨剂有关。再生基础油的抗氧化安定性不佳,是由于精制过程中脱除了油品中的抗氧化成分—含硫多环化合物,可通过添加苯三唑衍生物T551等金属减活型抗氧剂来改善。再生基础油的起泡性较大,需加大抗泡剂用量。研制的CF-4 10W/30柴油机油,其抗磨性、倾点等优于参比油,其它性能相当,完全可以作为商用柴油机油使用。     

Controllable Fabrication of Highly Uniform Sub-10 nm Nanoparticles from Spontaneous Confined Nanoemulsification

Sub-10 nm nanoparticles are known to exhibit extraordinary size-dependent properties for wide applications. Many approaches have been developed for synthesizing sub-10 nm inorganic nanoparticles, but the fabrication of sub-10 nm polymeric nanoparticles is still challenging. Here, a scalable, spontaneous confined nanoemulsification strategy that produces uniform sub-10 nm nanodroplets for template synthesis of sub-10 nm polymeric nanoparticles is proposed. This strategy introduces a high-concentration interfacial reaction to create overpopulated surfactants that are insoluble at the droplet surface. These overpopulated surfactants act as barriers, resulting in highly accumulated surfactants inside the droplet via a confined reaction. These surfactants exhibit significantly changed packing geometry, solubility, and interfacial activity to enhance the molecular-level impact on interfacial instability for creating sub-10 nm nanoemulsions via self-burst nanoemulsification. Using the nanodroplets as templates, the fabrication of uniform sub-10 nm polymeric nanoparticles, as small as 3.5 nm, made from biocompatible polymers and capable of efficient drug encapsulation is demonstrated. This work opens up brand-new opportunities to easily create sub-10 nm nanoemulsions and advanced ultrasmall functional nanoparticles.     

GZ-10型高精度数字式表面电阻测试仪的研制

静电火花是煤矿、加气站等有危险气体场所发生爆炸的主要点火源之一。为防止静电火花产生,关键是设备和材料必须具有抗静电性能,而评价聚合物制品抗静电性能的主要方法是用表面电阻测试仪测量其表面电阻。本文介绍了研制的新型GZ-10型高精度数字式表面电阻测试仪的系统组成及硬件设计。该表面电阻测试仪采用低阻档和高阻档两组测试电路,高阻档测试电路测量双取样电阻的电压,低阻档电路采用比例法,克服了普通表面电阻测试仪因被测电压或电流的变化而变化的缺点,保证了测量的准确性。     

Anti‐biofilm and anti‐virulence effects of silica oxide nanoparticle–conjugation of lectin purified from Pseudomonas aeruginosa

Pseudomonas aeruginosa lectin is purified and nanoparticle‐conjugated in an attempt to inhibit biofilm formation. Thirteen (23.6%) P. aeruginosa isolates are obtained from chicken meat samples, of which 30.8% are biofilm producers and 69.2% are lectin producers. Lectin is purified 36.8‐fold to final specific activity of 506.9 U/mg. Four nanoparticle types are prepared via laser ablation: platinum (Pt), gold (Au), silica oxide (SiO₂), and tin oxide (SnO₂). The four types are characterised, and pulse feeding is used to conjugate the lectin and nanoparticles. Pt, Au, SiO_2, and SnO₂ nanoparticles inhibit biofilm formation, especially SiO₂ nanoparticles, which have higher effectiveness when conjugated with purified lectin. SiO₂‐conjugated lectin significantly (p < 0.05) inhibits biofilm formation more effectively than control and other nanoparticle‐conjugated lectins. Au‐, Pt nanoparticle‐, and SnO₂‐conjugated lectins inhibit biofilm significantly compared with control (p < 0.05), and rhlR gene expression is decreased in the presence of SiO₂‐conjugated lectin. Furthermore, lectin and Pt, Au, SiO₂ and SnO₂ nanoparticles separately, and their conjugated lectins, are effective biofilm inhibitors. Of these, SiO₂‐conjugated lectin was most significant as an anti‐biofilm. Moreover, virulence factors regulon and RhlR were reduced by SiO₂‐conjugated lectin, indicating that this conjugation may also decrease the virulence of P. aeruginosa.     

Biodegradation of fenoxaprop-p-ethyl by bacteria isolated from sludge

A mixed bacterial population was isolated using enrichment in a basal medium containing increasing amounts of fenoxaprop-p-ethyl as a sole carbon source from sludge that had been exposed to fenoxaprop-p-ethyl production wastewater for about 2 years. Eight kinds of isolates could utilize fenoxaprop-p-ethyl, but only one was identified belonging to genus Alcaligenes, named Alcaligenes sp. H. In pure culture, there was 45.8, 66.0 and 69.5% loss of fenoxaprop-p-ethyl (initial concentration: 100, 50, 25 ppm, respectively) as the sole carbon source with biodegradation by Alcaligenes sp. H and fenoxaprop-p-ethyl degradation kinetics obeyed the first-order kinetics, the same as the fenoxaprop-p-ethyl biodegradation kinetics in soil. At least five degradation products of fenoxaprop-p-ethyl biodegradation by Alcaligenes sp. H and two degradation products of fenoxaprop-p-ethyl biodegradation by Huv separated by HPTLC. It is possible that the fenoxaprop-p-ethyl biodegradation by Alcaligenes sp. H includes the same pathway as that by Huv comparing with the Rf.     

Biosynthesis of γ ‐Fe2 O3 @CuO core–shell nanoclusters using aqueous extract of Sesbania grandiflora Linn fresh leaves,its characterisation,and antimicrobial activity studies against Staphylococcus aureus strains

The present study reports an eco‐friendly and rapid method for the synthesis of core–shell nanoclusters using the modified reverse micelle method. It is a green synthetic method which uses Sesbania grandiflora Linn extract which acts as a reducing and capping agent. It is observed that this method is very fast and convenient and the nanoclusters are formed with 5–10 min of the reaction time without using harsh conditions. The core–shell nanoclusters so prepared were characterised using UV–Vis spectroscopy, scanning electron microscopy, transmission electron microscopy, X‐ray diffraction, and X‐ray photoelectron spectroscopy. Further, their effective antibacterial activity towards the gram‐positive bacteria Staphylococcus aureus was found to be due to their smaller particle size.Inspec keywords: iron compounds, copper compounds, nanoparticles, particle size, nanofabrication, nanomedicine, biomedical materials, core‐shell nanostructures, antibacterial activity, ultraviolet spectra, visible spectra, microorganisms, reduction (chemical), scanning electron microscopy, transmission electron microscopy, X‐ray diffraction, X‐ray photoelectron spectraOther keywords: biosynthesis, γ‐Fe₂ O₃ ‐CuO core‐shell nanoclusters, aqueous extract, Sesbania grandiflora Linn fresh leaves, antimicrobial activity, Staphylococcus aureus strains, eco‐friendly method, modified reverse micelle method, green synthetic method, reducing agent, capping agent, UV‐visible spectroscopy, scanning electron microscopy, transmission electron microscopy, X‐ray diffraction, X‐ray photoelectron spectroscopy, antibacterial activity, gram‐positive bacteria Staphylococcus aureus, particle size, time 5 min to 10 min, Fe₂ O₃ ‐CuO     

Micromachined acoustic wave resonator isolated from substrate

This paper describes high Q, free-standing, narrow beam supported film bulk acoustic-wave resonators (FBARs) fabricated with silicon micromachining. The resonators are composed of metal/ZnO/metal/Si(x)Ny (or metal/ZnO/metal) composite layers, which are suspended by narrow Si(x)Ny/metal (or metal) beams to minimize energy leakage to the substrate. A layer of 0.5-microm thick parylene deposited and patterned over the Si(x)Ny/metal (or metal) beams is proven to enhance the sturdiness of the free-standing structure greatly. The highest Q (quality) factors we have obtained with this new structure are 1,587 and 769 at 2.7 and 5.1 GHz, respectively. This paper also describes the effect of removing the silicon-nitride support layer (to form air-backed FBARs that do not use any supporting layer below or above piezoelectric the ZnO layer sandwiched by two metal layers). The electromechanical coupling constant (Kt2) is improved from 3.2% to 6.8% when a 0.9-microm thick silicon-nitride support layer is removed.     

HTR-10燃料元件装卸软件系统的研制

为保证高温气冷实验堆燃料元件装卸系统的安全可靠运千古人有监视、、控制、管理和保护等功能的软件系统。燃料元件装卸系统以ＰＬＣ－ＩＰＣ为控制核心,软件采用多级结构。底层ＰＬＣ采用梯科编程进行现场控制,上层在ＩＰＣ基础上实现了燃料元件装卸系统运行过程监视、等功能,可对运行工艺实施诊断,向操作者合理的运行路线提示,进行故障预报警等。