bluuebunny/crossref_metadata_2025 huggingface dataset:
Evolution of Si Crystallographic Planes-Etching of Square and Circle Patterns in 25 wt % TMAH
Authors: Smiljanić Milče M. , Lazić Žarko , Radjenović Branislav , Radmilović-Radjenović Marija , Jović Vesna
Published: February 2019

Squares and circles are basic patterns for most mask designs of silicon microdevices. Evolution of etched Si crystallographic planes defined by square and circle patterns in the masking layer is presented and analyzed in this paper. The sides of square patterns in the masking layer are designed along predetermined  crystallographic directions. Etching of a (100) silicon substrate is performed in 25 wt % tetramethylammonium hydroxide (TMAH) water solution at the temperature of 80 °C. Additionally, this paper presents three-dimensional (3D) simulations of the profile evolution during silicon etching of designed patterns based on the level-set method. We analyzed etching of designed patterns in the shape of square and circle islands. The crystallographic planes that appear during etching of 3D structures in the experiment and simulated etching profiles are determined. A good agreement between dominant crystallographic planes through experiments and simulations is obtained. The etch rates of dominant exposed crystallographic planes are also analytically calculated.
Multi-Stage Particle Separation based on Microstructure Filtration and Dielectrophoresis
Authors: Yin Danfen , Zhang Xiaoling , Han Xianwei , Yang Jun , Hu Ning
Published: February 2019

Particle separation is important in chemical and biomedical analysis. Among all particle separation approaches, microstructure filtration which based particles size difference has turned into one of the most commonly methods. By controlling the movement of particles, dielectrophoresis has also been widely adopted in particle separation. This work presents a microfluidic device which combines the advantages of microfilters and dielectrophoresis to separate micro-particles and cells. A three-dimensional (3D) model was developed to calculate the distributions of the electric field gradient at the two filter stages. Polystyrene particles with three different sizes were separated by micropillar array structure by applying a 35-Vpp AC voltage at 10 KHz. The blocked particles were pushed off the filters under the negative dielectrophoretic force and drag force. A mixture of Haematococcus pluvialis cells and Bracteacoccus engadinensis cells with different sizes were also successfully separated by this device, which proved that the device can separate both biological samples and polystyrene particles.
Microfluidic Single-Cell Manipulation and Analysis: Methods and Applications
Authors: Luo Tao , Fan Lei , Zhu Rong , Sun Dong
Published: February 2019

In a forest of a hundred thousand trees, no two leaves are alike. Similarly, no two cells in a genetically identical group are the same. This heterogeneity at the single-cell level has been recognized to be vital for the correct interpretation of diagnostic and therapeutic results of diseases, but has been masked for a long time by studying average responses from a population. To comprehensively understand cell heterogeneity, diverse manipulation and comprehensive analysis of cells at the single-cell level are demanded. However, using traditional biological tools, such as petri-dishes and well-plates, is technically challengeable for manipulating and analyzing single-cells with small size and low concentration of target biomolecules. With the development of microfluidics, which is a technology of manipulating and controlling fluids in the range of micro- to pico-liters in networks of channels with dimensions from tens to hundreds of microns, single-cell study has been blooming for almost two decades. Comparing to conventional petri-dish or well-plate experiments, microfluidic single-cell analysis offers advantages of higher throughput, smaller sample volume, automatic sample processing, and lower contamination risk, etc., which made microfluidics an ideal technology for conducting statically meaningful single-cell research. In this review, we will summarize the advances of microfluidics for single-cell manipulation and analysis from the aspects of methods and applications. First, various methods, such as hydrodynamic and electrical approaches, for microfluidic single-cell manipulation will be summarized. Second, single-cell analysis ranging from cellular to genetic level by using microfluidic technology is summarized. Last, we will also discuss the advantages and disadvantages of various microfluidic methods for single-cell manipulation, and then outlook the trend of microfluidic single-cell analysis.
A Role of Exopolysaccharide Produced by Streptococcus thermophilus in the Intestinal Inflammation and Mucosal Barrier in Caco-2 Monolayer and Dextran Sulphate Sodium-Induced Experimental Murine Colitis
Authors: Chen Yun , Zhang Ming , Ren Fazheng
Published: February 2019

Exopolysaccharide (EPS) produced by probiotics may play an important role in gastrointestinal disease prevention, including ulcerative colitis. However, there is no literature reporting on the intervention effects of purified EPS. The aim of this study was to investigate the alleviating effect of the purified EPS produced by Streptococcus thermophilus MN-BM-A01 on murine model of colitis induced by dextran sulphate sodium (DSS). A water-soluble heteropolysaccharide (EPS-1) isolated from MN-BM-A01 was composed of rhamnose, glucose, galactose, and mannose in a molar ratio of 12.9:26.0:60.9:0.25, with molecular weight of 4.23 × 105 Da. After EPS-1 administration, the disease severity of mouse colitis was significantly alleviated, mainly manifesting as the decrease of disease activity index and mitigated colonic epithelial cell injury. Meanwhile, pro-inflammatory cytokines levels (tumor necrosis factor-α, interleukin-6, and interferon-γ) were significantly suppressed, the reduced expressions of tight junction protein (claudin-1, occludin, and E-canherin) were counteracted. In addition, the results in vitro showed that EPS-1 protected intestinal barrier integrity from the disruption by lipopolysaccharide in Caco-2 monolayer, increased expression of tight junction and alleviated pro-inflammatory response. Collectively, our study confirmed the protective effects of purified EPS produced by Streptococcus thermophilus on acute colitis via alleviating intestinal inflammation and improving mucosal barrier function.
Therapeutic Effect of Chitooligosaccharide Tablets on Lipids in High-Fat Diets Induced Hyperlipidemic Rats
Authors: Yang Di , Hu Canji , Deng Xiaoyi , Bai Yan , Cao Hua , Guo Jiao , Su Zhengquan
Published: February 2019

Chitooligosaccharide is beneficial for inhibiting dyslipidemia and reducing atherosclerotic and hyperlipidemic risk. The purpose of this study was to investigate the cholesterol-regulating effects and potential mechanisms of Chitooligosaccharide tablets (CFTs) in high-fat diet-induced hyperlipidemic rats. The results revealed that CFTs can regulate serum lipid levels in hyperlipidemic rats in a dosage-dependent manner. Synchronously, gene expressions related to cholesterol excretion were upregulated in a dosage-dependent manner, including cholesterol 7α-hydroxylase (CYP7A1), liver X receptor α (LXRA), peroxisome proliferation-activated receptor-α (PPARα) and low-density lipoprotein receptor (LDLR), whereas cholesterol synthetic gene expressions including 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) and sterol-responsive element binding protein-2 (SREBP2) were reduced. This work highlights that CFTs have potential as natural products to prevent and treat metabolic hyperlipidemia syndrome, probably due to the reduction of cholesterol biosynthesis and through cholesterol elimination; they also improve the pathological changes of liver tissue in rats, alleviate liver damage, maintain normal lipid metabolism in the liver, ameliorate hepatic glycolipid disorders and accelerate TC operation, and reduce blood lipid levels.
Optical Biosensors Based on Silicon-On-Insulator Ring Resonators: A Review
Authors: Steglich Patrick , Hülsemann Marcel , Dietzel Birgit , Mai Andreas
Published: February 2019

Recent developments in optical biosensors based on integrated photonic devices are reviewed with a special emphasis on silicon-on-insulator ring resonators. The review is mainly devoted to the following aspects: (1) Principles of sensing mechanism, (2) sensor design, (3) biofunctionalization procedures for specific molecule detection and (4) system integration and measurement set-ups. The inherent challenges of implementing photonics-based biosensors to meet specific requirements of applications in medicine, food analysis, and environmental monitoring are discussed.
Skin Electrical Resistance Measurement of Oxygen-Containing Terpenes as Penetration Enhancers: Role of Stratum Corneum Lipids
Authors: Zhu Xue-min , Li Yu , Xu Fei , Gu Wei , Yan Guo-jun , Dong Jie , Chen Jun
Published: February 2019

The measurement of skin electrical resistance (SER) has drawn a great deal of attention for the rapid screening of transdermal penetration enhancers (PEs). However, the mechanisms underlying the SER measurement are still unclear. This study was to investigate the effects and mechanisms of seven oxygen-containing terpenes on the SER kinetics. Stratum corneum (SC) lipids were proved to play a key role in SER measurement. Then, the factors affecting the SER measurement were optimized. By the determination of SER kinetics, cyclic terpenes (1,8-cineole, terpinen-4-ol, menthol and α-terpineol) were demonstrated to possess higher enhancement ratio (ER) values compared with linear terpenes (linalool, geraniol and citral). For the first time, the linear correlation was found between ER of terpenes and the interaction energy of terpene–ceramide complexes revealed by molecular simulation. The attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR) analysis revealed that the effect of cyclic terpenes on SC lipid arrangement was obviously stronger than that of linear terpenes. In addition, by evaluating HaCaT skin cell viability, little difference was found between the toxicities of cyclic and linear terpenes. In conclusion, measurement of SER could be a feasible approach for the efficient evaluation of the PEs that mainly act on SC lipids.
Mycotoxin Incidence in Some Fish Products: QuEChERS Methodology and Liquid Chromatography Linear Ion Trap Tandem Mass Spectrometry Approach
Authors: Tolosa Josefa , Barba Francisco J. , Font Guillermina , Ferrer Emilia
Published: February 2019

The inclusion of vegetal raw materials in feed for fish farming has increased the risk of mycotoxin occurrence in feed, as well as in edible tissues from fish fed with contaminated feed, due to the carry-over to muscle portions. Therefore, the objective of this study was to evaluate the occurrence of 15 mycotoxins in processed fish products, which are commonly consumed, such as smoked salmon and trout, different types of sushi, and gula substitutes. A QuEChERS method was employed to perform the mycotoxin extraction from fish samples. For mycotoxin identification and quantitation, the selected technique was the liquid chromatography-tandem mass spectrometry linear ion trap (LC-MS/MS-LIT). Smoked fish and sushi samples results were negative regarding the presence of all 15 mycotoxins studied. In contrast, small amounts of fusarenon-X and enniatin B were found in gula substitute samples.
Catechin in Human Health and Disease
Authors: Isemura Mamoru
Published: February 2019

Catechin, the name of which is derived from catechu of the extract of Acacia catechu L [...]
Comparing the Effects of Different Unsaturated Fatty Acids on Fermentation Performance of Saccharomyces cerevisiae and Aroma Compounds during Red Wine Fermentation
Authors: Liu Pei-Tong , Duan Chang-Qing , Yan Guo-Liang
Published: February 2019

To understand the individual enological function of different unsaturated fatty acids (UFAs), the separated effects of three different UFAs, linoleic acid (LA), oleic acid (OA), and α-linolenic acid (ALA), on yeast fermentation and aroma compounds were investigated in the alcoholic fermentation of Cabernet Sauvignon wine. The results showed that, besides concentration, UFAs types could also influence fermentation process and volatiles in final wine. Low concentrations of UFAs (12 and 60 mg/L), especially LA and OA, significantly promoted fermentation activity and most volatiles when compared to the control, however, the effect became the inhibition with increasing concentrations of UFAs (120 and 240 mg/L). It was interesting to find that OA addition (12 and 60 mg/L) could generate more acetate esters (especially isoamyl acetate) in wine, while 12 mg/L LA facilitated more fatty acids formation (octanoic acid and decanoic acid). In comparison, 120 and 240 mg/L ALA produced more amount of C6 alcohols (1-hexanol) and higher alcohols (isobutyl alcohol and 2,3-butanediol). UFAs additions were unfavorable for ethyl esters formation, except for an increment of ethyl hexanoate in 12 mg/L OA wine. As a result, different aromatic profiles of wines were generated by variations of UFAs types and levels, as shown by PCA. The transcriptional data revealed that the expressions of aroma-related genes, such as BAT1, BAT2, PDC1, PDC5, PDC6, ACC1, FAS1, ATF1, EEB1, and EHT1 were correlated with aroma compounds productions in different treatments. Our data suggested that the three UFAs have different enological functions and they could generate different aromatic profiles. Thus, besides concentrations, it is essential to consider the types of UFAs when applying the strategy to adjust UFAs contents to modulate the aromatic quality of wines.
‘Seeing’ Strain in Soft Materials
Authors: Xia Zhiyong , Alphonse Vanessa D. , Trigg Doug B. , Harrigan Tim P. , Paulson Jeff M. , Luong Quang T. , Lloyd Evan P. , Barbee Meredith H. , Craig Stephen L.
Published: February 2019

Several technologies can be used for measuring strains of soft materials under high rate impact conditions. These technologies include high speed tensile test, split Hopkinson pressure bar test, digital image correlation and high speed X-ray imaging. However, none of these existing technologies can produce a continuous 3D spatial strain distribution in the test specimen. Here we report a novel passive strain sensor based on poly(dimethyl siloxane) (PDMS) elastomer with covalently incorporated spiropyran (SP) mechanophore to measure impact induced strains. We have shown that the incorporation of SP into PDMS at 0.25 wt% level can adequately measure impact strains via color change under a high strain rate of 1500 s−1 within a fraction of a millisecond. Further, the color change is fully reversible and thus can be used repeatedly. This technology has a high potential to be used for quantifying brain strain for traumatic brain injury applications.
Passive Commuting and Higher Sedentary Time Is Associated with Vitamin D Deficiency in Adult and Older Women: Results from Chilean National Health Survey 2016–2017
Authors: Solis-Urra Patricio , Cristi-Montero Carlos , Romero-Parra Javier , Zavala-Crichton Juan Pablo , Saez-Lara Maria Jose , Plaza-Diaz Julio
Published: February 2019

The aim was to investigate the associations between different physical activity (PA) patterns and sedentary time (ST) with vitamin D deficiency (<12 ng/mL) in a large sample of Chilean women. In this cross-sectional study, the final sample included 1245 adult and 686 older women. The PA levels, mode of commuting, ST, and leisure-time PA were self-reported. Vitamin D deficiency was defined as <12 ng/mL and insufficiency as <20 ng/mL. A higher ST was associated with vitamin D deficiency (odds ratio (OR): 2.4, 95%: 1.6–4.3) in adults, and passive commuting was associated with vitamin D deficiency in older (OR: 1.7, 95%: 1.1–2.7). Additionally, we found a joint association in the high ST/passive commuting group in adults (OR: 2.8, 95%: 1.6–4.9) and older (OR: 2.8, 95%: 1.5–5.2) with vitamin D deficiency, in respect to low ST/active commuting. The PA levels and leisure-time PA were not associated with vitamin D deficiency. In conclusion, mode of commuting and ST seems important variables related to vitamin D deficiency. Promoting a healthy lifestyle appears important also for vitamin D levels in adult and older women. Further studies are needed to establish causality of this association and the effect of vitamin D deficiency in different diseases in this population.
Do a Few Weeks Matter? Late Preterm Infants and Breastfeeding Issues
Authors: Crippa Beatrice Letizia , Colombo Lorenzo , Morniroli Daniela , Consonni Dario , Bettinelli Maria Enrica , Spreafico Irene , Vercesi Giulia , Sannino Patrizio , Mauri Paola Agnese , Zanotta Lidia , Canziani Annalisa , Roggero Paola , Plevani Laura , Bertoli Donatella , Zorzan Stefania , Giannì Maria Lorella , Mosca Fabio
Published: February 2019

The late preterm infant population is increasing globally. Many studies show that late preterm infants are at risk of experiencing challenges common to premature babies, with breastfeeding issues being one of the most common. In this study, we investigated factors and variables that could interfere with breastfeeding initiation and duration in this population. We conducted a prospective observational study, in which we administered questionnaires on breastfeeding variables and habits to mothers of late preterm infants who were delivered in the well-baby nursery of our hospital and followed up for three months after delivery. We enrolled 149 mothers and 189 neonates, including 40 pairs of twins. Our findings showed that late preterm infants had a low rate of breastfeeding initiation and early breastfeeding discontinuation at 15, 40 and 90 days of life. The mothers with higher educational levels and previous positive breastfeeding experience had a longer breastfeeding duration. The negative factors for breastfeeding were the following: Advanced maternal age, Italian ethnicity, the feeling of reduced milk supply and having twins. This study underlines the importance of considering these variables in the promotion and protection of breastfeeding in this vulnerable population, thus offering mothers tailored support.
The Food Energy/Protein Ratio Regulates the Rat Urea Cycle but Not Total Nitrogen Losses
Authors: Oliva Laia , Alemany Marià , Remesar Xavier , Fernández-López José-Antonio
Published: February 2019

Nitrogen balance studies have shown that a portion of the N ingested but not excreted is not accounted for. We compared several diets (standard, high-fat, high-protein, and self-selected cafeteria) to determine how diet-dependent energy sources affect nitrogen handling, i.e., the liver urea cycle. Diet components and rat homogenates were used for nitrogen, lipid, and energy analyses. Plasma urea and individual amino acids, as well as liver urea cycle enzyme activities, were determined. Despite ample differences in N intake, circulating amino acids remained practically unchanged in contrast to marked changes in plasma urea. The finding of significant correlations between circulating urea and arginine-succinate synthase and lyase activities supported their regulatory role of urea synthesis, the main N excretion pathway. The cycle operation also correlated with the food protein/energy ratio, in contraposition to total nitrogen losses and estimated balance essentially independent of dietary energy load. The different regulation mechanisms observed have potentially important nutritional consequences, hinting at nitrogen disposal mechanisms able to eliminate excess nitrogen under conditions of high availability of both energy and proteins. Their operation reduces urea synthesis to allow for a safe (albeit unknown) mechanism of N/energy excess accommodation.
Chlorambucil Conjugated Ugi Dendrimers with PAMAM-NH2 Core and Evaluation of Their Anticancer Activity
Authors: Seixas Nalin , Ravanello Bruno B. , Morgan Ibrahim , Kaluđerović Goran N. , Wessjohann Ludger A.
Published: February 2019

Herein, a new Ugi multicomponent reaction strategy is described to enhance activity and solubility of the chemotherapeutic drug chlorambucil through its conjugation to poly(amidoamine) (PAMAM-NH2) dendrimers with the simultaneous introduction of lipidic (i-Pr) and cationic (–NH2) or anionic (–COOH) groups. Standard viability assays were used to evaluate the anticancer potential of the water-soluble dendrimers against PC-3 prostate and HT-29 colon cancer cell lines, as well as non-cancerous mouse NIH3T3 fibroblasts. It could be demonstrated that the anticancer activity against PC-3 cells was considerably improved when both chlorambucil and –NH2 (cationic) groups were present on the dendrimer surface (1b). Additionally, this dendrimer showed activity only against the prostate cancer cells (PC-3), while it did not affect colon cancer cells and fibroblasts significantly. The cationic chlorambucil-dendrimer 1b blocks PC-3 cells in the G2/M phase and induces caspase independent apoptosis.
Gold Nanocage-Incorporated Poly(ε-Caprolactone) (PCL) Fibers for Chemophotothermal Synergistic Cancer Therapy
Authors: Park Ju Hyang , Seo Hojun , Kim Da In , Choi Ji Hyun , Son Jin Ho , Kim Jongbok , Moon Geon Dae , Hyun Dong Choon
Published: February 2019

This paper introduces a new fibrous system for synergistic cancer therapy, which consists of gold nanocage (AuNC)-loaded poly(ε-caprolactone) (PCL) fibers with encapsulation of a chemotherapeutic anticancer drug in their core and loading of a phase-changeable fatty acid in their sheath. Under on–off switching of near-infrared (NIR) light irradiation, the excellent photothermal ability and photostability of AuNCs allows repeated, significant heating of the fibers to a temperature available to hyperthermia. Simultaneously, the NIR light-induced heat generation enables the melting out of the loaded fatty acid, leading to a rapid release of the drug molecules from the fibers. The combination of this NIR light-triggered drug release with the repeated hyperthermia treatment exhibits excellent anticancer efficacy.
In Vitro Anticancer Activity of Extracellular Vesicles (EVs) Secreted by Gingival Mesenchymal Stromal Cells Primed with Paclitaxel
Authors: Coccè Valentina , Franzè Silvia , Brini Anna Teresa , Giannì Aldo Bruno , Pascucci Luisa , Ciusani Emilio , Alessandri Giulio , Farronato Giampietro , Cavicchini Loredana , Sordi Valeria , Paroni Rita , Dei Cas Michele , Cilurzo Francesco , Pessina Augusto
Published: February 2019

Interdental papilla are an interesting source of mesenchymal stromal cells (GinPaMSCs), which are easy to isolate and expand in vitro. In our laboratory, GinPaMSCs were isolated, expanded, and characterized by studying their secretome before and after priming with paclitaxel (PTX). The secretome of GinPaMSCs did not affect the growth of cancer cell lines tested in vitro, whereas the secretome of GinPaMSCs primed with paclitaxel (GinPaMSCs/PTX) exerted a significant anticancer effect. GinPaMSCs were able to uptake and then release paclitaxel in amounts pharmacologically effective against cancer cells, as demonstrated in vitro by the direct activity of GinPaMSCs/PTX and their secretome against both human pancreatic carcinoma and squamous carcinoma cells. PTX was associated with extracellular vesicles (EVs) secreted by cells (EVs/PTX), suggesting that PTX is incorporated into exosomes during their biogenesis. The isolation of mesenchymal stromal cells (MSCs) from gingiva is less invasive than that from other tissues (such as bone marrow and fat), and GinPaMSCs provide an optimal substrate for drug-priming to obtain EVs/PTX having anticancer activity. This research may contribute to develop new strategies of cell-mediated drug delivery by EVs that are easy to store without losing function, and could have a superior safety profile in therapy.
Effect of Solvents on the Electrical and Morphological Characteristics of Polymer Solar Cells
Authors: Kim Jun Young
Published: February 2019

The nanoscale morphology of poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl-C71. butyric acid methylester (PCBM) blend film is affected by various parameters such as the solvent, coating, and thermal annealing conditions. We investigated the effect of solvents on the performance of inverted solar cells based on the active layer of a P3HT:PCBM bulk heterojunction. P3HT and PCBM (weight ratio 1:0.8) were dissolved in chlorobenzene (CB) and dichlorobenzene (DCB). The difference in the volatility characteristics of the solvents resulted in different P3HT crystallite morphologies. The difference in the P3HT:PCBM film morphology was systemically investigated via atomic force microscopy, ultraviolet (UV)-visible absorption spectroscopy, X-ray diffraction, and electrical impedance spectroscopy. The DCB solvent lead to better P3HT crystallinity and device performance. For example, the short-circuit current density (JSC) and the power conversion efficiency (PCE) of the device using DCB (9.89 mA/cm2 and 3.62%, respectively) were larger than those (9.12 mA/cm2 and 3.01%) of the device using CB.
Novel Oligo-Ester-Ether-Diol Prepared by Waste Poly(ethylene terephthalate) Glycolysis and Its Use in Preparing Thermally Stable and Flame Retardant Polyurethane Foam
Authors: Hoang Cuong N. , Pham Chi T. , Dang Thu M. , Hoang DongQuy , Lee Pyoung-Chan , Kang Soo-Jung , Kim Jinhwan
Published: February 2019

Rigid polyurethane foam (PUF) was successfully prepared from a novel oligo-ester-ether-diol obtained from the glycolysis of waste poly(ethylene terephthalate) (PET) bottles via reaction with diethylene glycol (DEG) in the presence of ZnSO4·7H2O. The LC-MS analysis of the oligodiol enabled us to identify 67 chemical homologous structures that were composed of zero to four terephthalate (T) ester units and two to twelve monoethylene glycol (M) ether units. The flame retardant, morphological, compression, and thermal properties of rigid PUFs with and without triphenyl phosphate (TPP) were determined. The Tg values showed that TPP played a role of not only being a flame retardant, but also a plasticizer. PUF with a rather low TPP loading had an excellent flame retardancy and high thermal stability. A loading of 10 wt % TPP not only achieved a UL-94 V-0 rating, but also obtained an LOI value of 21%. Meanwhile, the PUF without a flame retardant did not achieve a UL-94 HB rating; the sample completely burned to the holder clamp and yielded a low LOI value (17%). The fire properties measured with the cone calorimeter were also discussed, and the results further proved that the flame retardancy of the PUF with the addition of TPP was improved significantly. The polymeric material meets the demands of density and compression strength for commercial PUF, as well as the needs of environmental development. The current study may help overcome the drawback of intrinsic high flammability and enlarge the fire safety applications of materials with a high percentage of recycled PET.
Improved Mechanical Properties of Copoly(Phthalazinone Ether Sulphone)s Composites Reinforced by Multiscale Carbon Fibre/Graphene Oxide Reinforcements: A Step Closer to Industrial Production
Authors: Li Nan , Yang Xiuxiu , Bao Feng , Pan Yunxing , Wang Chenghao , Chen Bo , Zong Lishuai , Liu Chengde , Wang Jinyan , Jian Xigao
Published: February 2019

The properties of carbon fibre (CF) reinforced composites rely heavily on the fibre-matrix interface. To enhance the interfacial properties of CF/copoly(phthalazinone ether sulfone)s (PPBES) composites, a series of multiscale hybrid carbon fibre/graphene oxide (CF/GO) reinforcements were fabricated by a multistep deposition strategy. The optimal GO loading in hybrid fibres was investigated. Benefiting from the dilute GO aqueous solution and repeated deposition procedures, CF/GO (0.5%) shows a homogeneous distribution of GO on the hybrid fibre surface, which is confirmed by scanning electron microscopy, atomic force microscope, and X-ray photoelectron spectroscopy, thereby ensuring that its PPBES composite possesses the highest interlaminar shear strength (91.5 MPa) and flexural strength (1886 MPa) with 16.0% and 24.1% enhancements, respectively, compared to its non-reinforced counterpart. Moreover, the incorporation of GO into the interface is beneficial for the hydrothermal ageing resistance and thermo-mechanical properties of the hierarchical composite. This means that a mass production strategy for enhancing mechanical properties of CF/PPBES by regulating the fiber-matrix interface was developed.
Glycosylated Artificial Virus-Like Hybrid Vectors for Advanced Gene Delivery
Authors: Pinnapireddy Shashank Reddy , Raafat El Assy Mohamed , Schlote Patrick , Bakowsky Udo
Published: February 2019

The major obstacle facing efficient gene therapy is the development of reliable delivery vehicles, which are both nontoxic and biocompatible and possess efficient cell-specific gene delivery. Previously, hybrid delivery vehicles comprising anionic liposomes and cationic polymers have been used successfully for gene therapy. In this study, hybrid vectors based on glycosylated artificial viral envelopes (including two novel compositions mimicking HIV and HSV envelopes) and polyethylenimine were morphologically and physiologically characterised. Transfection studies showed that the hybrid vectors based on the control liposomes, and their glycosylated modifications, had significantly higher transfection rates compared to the polyplexes. Improvement in the transfection efficiency was observed with the glycosylated HIV- and HSV-mimicking hybrid vectors, which also showed a safe biocompatibility profile based on the cytotoxicity and haemocompatibility assays. These glycosylated artificial viral envelope-based hybrid vectors could be used as safe gene delivery systems with potential to become new compositions for efficient nonviral gene therapy.
Improvement to the Carrier Transport Properties of CdZnTe Detector Using Sub-Band-Gap Light Radiation
Authors: Luo Xiangxiang , Zha Gangqiang , Xu Lingyan , Jie Wanqi
Published: February 2019

The effects of sub-band-gap light radiation on the performance of CdZnTe photon-counting X-ray detectors were studied using infrared light with different wavelengths in the region of 980–1550 nm. The performance of the detectors for X-ray detection was improved by the radiation of infrared light with the wavelengths of 1200 nm and 1300 nm. This was because the increase of the electron indirect transition, and the weakening of the built-in electric field induced by the trapped holes, reduced the drift time of the carrier, and increased the charge collection efficiency. To further analyze the intrinsic behavior of the trapped charge, the deep-level defects of CdZnTe crystal were measured by thermally stimulated current spectroscopy (TSC). The deep-level defect indicated by the trap named T4 in TSC spectra with the ionization energy of 0.43 eV should be responsible for the performance deterioration of CdZnTe detectors.
A Review on Methods for Random Motion Detection and Compensation in Bio-Radar Systems
Authors: Gouveia Carolina , Vieira José , Pinho Pedro
Published: February 2019

The bio-radar system can measure vital signals accurately, by using the Doppler effect principle, which relates the received signal properties to the distance change between the radar antennas and the subject chest-wall. These systems have countless applications, from short range detection to assist in rescue missions, to long-term applications as for the continuous sleeping monitoring. Once the main applications of these systems intend to monitor subjects during long periods of time and under noisy environments, it is impossible to guarantee the patient immobilization, hence its random motion, as well as other clutter sources, will interfere in the acquired signals. Therefore, the signal processing algorithms developed for these applications have been facing several challenges regarding the random motion detection and mitigation. In this paper, an extended review on the already implemented methods is done, considering continuous wave radars. Several sources of random motion are considered, along with different approaches to compensate the distortions caused by them.
A Low-Complexity FMCW Surveillance Radar Algorithm Using Two Random Beat Signals
Authors: Kim Bong-seok , Jin Youngseok , Kim Sangdong , Lee Jonghun
Published: February 2019

This paper proposes a low-complexity frequency-modulated continuous wave (FMCW) surveillance radar algorithm using random dual chirps in order to overcome the blind-speed problem and reduce the computational complexity. In surveillance radar algorithm, the most widely used moving target indicator (MTI) algorithm is proposed to effectively remove clutter. However, the MTI algorithm has a so-called ‘blind-speed problem’ that cannot detect a target of a specific velocity. In this paper, we try to solve the blind-speed problem of MTI algorithm by randomly selecting two beat signals selected for MTI for each frame. To further reduce the redundant complexity, the proposed algorithm first performs one-dimensional fast Fourier transform (FFT) for range detection and performs multidimensional FFT only when it is determined that a target exists at each frame. The simulation results show that despite low complexity, the proposed algorithm detects moving targets well by avoiding the problem of blind speed. Furthermore, the effectiveness of the proposed algorithm was verified by performing an experiment using the FMCW radar system in a real environment.
Real-Time Monitoring of the Position and Orientation of a Radio Telescope Sub-Reflector with Fiber Bragg Grating Sensors
Authors: Zhao Yong , Du Jingli , Xu Qian , Bao Hong
Published: February 2019

Environmental loads linked with pointing errors, such as gravity, thermal gradients, and wind disturbances, are a serious concern for large-aperture high-frequency radio telescopes. For the purpose of maintaining the pointing performance of a telescope, a contact measurement scheme is proposed on basis of fiber Bragg grating (FBG) strain sensors that can monitor the sub-reflector shift in real time as the input data of the adjustment system. In this scheme, the relationship between the in situ strain measurement and the deformation of the supporting structure, which is the main cause of sub-reflector shift, is deduced using the inverse Finite Element Method (iFEM). Finally, experimental studies are carried out on a simple physical structure model to validate the effectiveness and accuracy of the contact measurement scheme.
IoT-Based Resource Control for In-Vehicle Infotainment Services: Design and Experimentation
Authors: Choi Dong-Kyu , Jung Joong-Hwa , Kim Ji-In , Gohar Moneeb , Koh Seok-Joo
Published: February 2019

A variety of in-vehicle infotainment (IVI) devices and services have been developed by many vehicle vendors and software companies, which include navigation systems, cameras, speakers, headrest displays, and heating seat. However, there has not been enough research on how to effectively control and manage numerous IVI resources (devices and contents), so as to provide users with more enhanced services. This paper proposes a framework of resource control for IVI services so as to efficiently manage the IVI resources within an automobile. Differently from conventional IVI systems, in the proposed scheme, the IVI-Master is newly introduced for overall control of IVI resources, and IVI users are divided into owner and users. In addition, the IVI resources are classified as personal resources and shared resources, which are managed by the IVI-Master using the Lightweight Machine-to-Machine (LWM2M) standard. The proposed IoT-based IVI resource control scheme was implemented and tested. The experimental results showed that the proposed scheme can be used to effectively manage IVI resources for users. Additionally, the proposed resource control scheme shows lower bandwidth usage than the existing scheme.
Cathode Design Optimization toward the Wide-Pressure-Range Miniature Discharge Ion Source for a Vacuum Micropump
Authors: Yao Tongtong , Tang Fei , Zhang Jian , Wang Xiaohao
Published: February 2019

It is difficult to generate and maintain the vacuum level in vacuum MEMS (Micro-Electro-Mechanical Systems) devices. Currently, there is still no single method or device capable of generating and maintaining the desired vacuum level in a vacuum device for a long time. This paper proposed a new wide-pressure-range miniature ion source, which can be applied to a vacuum micropump. The miniature ion source consists only of silicon electrodes and a glass substrate. Its operating pressure range covers seven orders of magnitude, starting from atmospheric pressure, a promising solution to the difficulty. Based on the principle of gas discharge, the ion source features a simple two-electrode structure with a two-stage electrode spacing, operating under DC voltage excitation. The first-stage electrode spacing of the ion source is small enough to ensure that it starts working at atmospheric pressure down to a certain reduced pressure when it automatically switches to discharge at the larger second-stage electrode spacing and operates from that pressure down to a high vacuum. Two configurations of the ion source have been tested: without-magnet, operating from atmospheric pressure down to 1 mbar; and with-magnet, operating from atmospheric pressure to 10−4 mbar, which covers seven orders of magnitude of pressure. The ion source can be applied not only to a MEMS ion pump to meet demands of a variety of vacuum MEMS devices, but can also be applied to other devices, such as vacuum microgauges and mass spectrometers.
A Gas Sensing Channel Composited with Pristine and Oxygen Plasma-Treated Graphene
Authors: Wu Haiyang , Bu Xiangrui , Deng Minming , Chen Guangbing , Zhang Guohe , Li Xin , Wang Xiaoli , Liu Weihua
Published: February 2019

Oxygen plasma treatment has been reported as an effective way of improving the response of graphene gas sensors. In this work, a gas sensor based on a composite graphene channel with a layer of pristine graphene (G) at the bottom and an oxygen plasma-treated graphene (OP-G) as a covering layer was reported. The OP-G on top provided oxygen functional groups and serves as the gas molecule grippers, while the as-grown graphene beneath serves as a fast carrier transport path. Thus, the composite channel (OP-G/G) demonstrated significantly improved response in NH3 gas sensing tests compared with the pristine G channel. Moreover, the OP-G/G channel showed faster response and recovering process than the OP-G channel. Since this kind of composite channel is fabricated from chemical vapor deposited graphene and patterned with standard photolithography, the device dimension was much smaller than a gas sensor fabricated from reduced graphene oxide and it is favorable for the integration of a large number of sensing units.
Approaching Sustainable Energy Management Operations in a Multinational Industrial Corporation
Authors: Sannö Anna , Johansson Maria T. , Thollander Patrik , Wollin Johan , Sjögren Birgitta
Published: February 2019

A large share of the energy efficiency improvement measures available for industrial companies remains unadopted due to the existence of various barriers to energy efficiency. One of the main means of overcoming barriers to energy efficiency is via energy management operations. The major parts of the published scientific papers have covered energy management on a company level or on a sector level. However, so far, the literature is scarce regarding empirical studies on energy management on a corporate level. With the aim of filling the research gap, the aim of this paper is to empirically assess the performance of an in-house energy management program adoption from the year of initiation and four years ahead in the multinational company Volvo CE. The paper was conducted as a case study including a participative approach, which has not previously been done in energy management research. This paper adds value, through complementing the existing literature on energy management on a factory or sector level, by highlighting the importance of leadership, speed of execution, and cultural transformation on a corporate level.
Structure Elucidation and Biological Evaluation of Maitotoxin-3, a Homologue of Gambierone, from Gambierdiscus belizeanus
Authors: Boente-Juncal Andrea , Álvarez Mercedes , Antelo Álvaro , Rodríguez Inés , Calabro Kevin , Vale Carmen , Thomas Olivier , Botana Luis
Published: February 2019

Gambierdiscus species are the producers of the marine toxins ciguatoxins and maitotoxins which cause worldwide human intoxications recognized as Ciguatera Fish Poisoning. A deep chemical investigation of a cultured strain of G. belizeanus, collected in the Caribbean Sea, led to the identification of a structural homologue of the recently described gambierone isolated from the same strain. The structure was elucidated mainly by comparison of NMR and MS data with those of gambierone and ascertained by 2D NMR data analyses. Gratifyingly, a close inspection of the MS data of the new 44-methylgambierone suggests that this toxin would actually correspond to the structure of maitotoxin-3 (MTX3, m/z 1039.4957 for the protonated adduct) detected in 1994 in a Pacific strain of Gambierdiscus and recently shown in routine monitoring programs. Therefore, this work provides for the first time the chemical identification of the MTX3 molecule by NMR. Furthermore, biological data confirmed the similar activities of both gambierone and 44-methylgambierone. Both gambierone and MTX3 induced a small increase in the cytosolic calcium concentration but only MTX3 caused cell cytotoxicity at micromolar concentrations. Moreover, chronic exposure of human cortical neurons to either gambierone or MTX3 altered the expression of ionotropic glutamate receptors, an effect already described before for the synthetic ciguatoxin CTX3C. However, even when gambierone and MTX3 affected glutamate receptor expression in a similar manner their effect on receptor expression differed from that of CTX3C, since both toxins decreased AMPA receptor levels while increasing N-methyl-d-aspartate (NMDA) receptor protein. Thus, further studies should be pursued to clarify the similarities and differences in the biological activity between the known ciguatoxins and the new identified molecule as well as its contribution to the neurological symptoms of ciguatera.
Senescent Cells in Early Vascular Ageing and Bone Disease of Chronic Kidney Disease—A Novel Target for Treatment
Authors: Hobson Sam , Arefin Samsul , Kublickiene Karolina , Shiels Paul G. , Stenvinkel Peter
Published: February 2019

Together with bone-mineral disorders, premature vascular ageing is a common feature of the uremic phenotype. A detailed understanding of mechanisms involved remains unclear and warrants further research. Available treatment options for end stage renal disease are principally dialysis and organ transplantation, as other treatment alternatives have proven insufficient. Chronic kidney disease (CKD) has been proposed as a model of early vascular and bone ageing, with accumulating evidence supporting the contribution of cellular senescence and the senescence-associated secretory phenotype (SASP) to cardiovascular pathology in CKD. Correspondingly, novel therapies based around the use of senolytic compounds and nuclear factor-erythroid-2-related factor 2 (Nrf2) agonists, have been suggested as attractive novel treatment options. In this review, we detail the contribution of the uremic environment to these processes underpinning ageing and how these relate to vascular health.
Mandibular Bone Loss after Masticatory Muscles Intervention with Botulinum Toxin: An Approach from Basic Research to Clinical Findings
Authors: Balanta-Melo Julián , Toro-Ibacache Viviana , Kupczik Kornelius , Buvinic Sonja
Published: February 2019

The injection of botulinum toxin type A (BoNT/A) in the masticatory muscles, to cause its temporary paralysis, is a widely used intervention for clinical disorders such as oromandibular dystonia, sleep bruxism, and aesthetics (i.e., masseteric hypertrophy). Considering that muscle contraction is required for mechano-transduction to maintain bone homeostasis, it is relevant to address the bone adverse effects associated with muscle condition after this intervention. Our aim is to condense the current and relevant literature about mandibular bone loss in fully mature mammals after BoNT/A intervention in the masticatory muscles. Here, we compile evidence from animal models (mice, rats, and rabbits) to clinical studies, demonstrating that BoNT/A-induced masticatory muscle atrophy promotes mandibular bone loss. Mandibular bone-related adverse effects involve cellular and metabolic changes, microstructure degradation, and morphological alterations. While bone loss has been detected at the mandibular condyle or alveolar bone, cellular and molecular mechanisms involved in this process must still be elucidated. Further basic research could provide evidence for designing strategies to control the undesired effects on bone during the therapeutic use of BoNT/A. However, in the meantime, we consider it essential that patients treated with BoNT/A in the masticatory muscles be warned about a putative collateral mandibular bone damage.
Vipera berus berus Venom from Russia: Venomics, Bioactivities and Preclinical Assessment of Microgen Antivenom
Authors: Al-Shekhadat Ruslan I. , Lopushanskaya Ksenia S. , Segura Álvaro , Gutiérrez José María , Calvete Juan J. , Pla Davinia
Published: February 2019

The common European adder, Vipera berus berus, is a medically relevant species, which is widely distributed in Russia and thus, is responsible for most snakebite accidents in Russia. We have investigated the toxic and enzymatic activities and have determined the proteomic composition of its venom. Phospholipases A2 (PLA2, 25.3% of the venom proteome), serine proteinases (SVSP, 16.2%), metalloproteinases (SVMP, 17.2%), vasoactive peptides (bradykinin-potentiating peptides (BPPs), 9.5% and C-type natriuretic peptides (C-NAP, 7.8%), cysteine-rich secretory protein (CRISP, 8%) and L-amino acid oxidase (LAO, 7.3%) represent the major toxin classes found in V. b. berus (Russia) venom. This study was also designed to assess the in vivo and in vitro preclinical efficacy of the Russian Microgen antivenom in neutralizing the main effects of V. b. berus venom. The results show that this antivenom is capable of neutralizing the lethal, hemorrhagic and PLA2 activities. Third-generation antivenomics was applied to quantify the toxin-recognition landscape and the maximal binding capacity of the antivenom for each component of the venom. The antivenomics analysis revealed that 6.24% of the anti-V. b. berus F(ab’)2 molecules fraction are toxin-binding antibodies, 60% of which represent clinically relevant antivenom molecules.
Control of Acute Arboviral Infection by Natural Killer Cells
Authors: Maucourant Christopher , Petitdemange Caroline , Yssel Hans , Vieillard Vincent
Published: February 2019

The recent explosive pandemic of chikungunya virus (CHIKV) followed by Zika (ZIKV) virus infections occurring throughout many countries represents the most unexpected arrival of arthropod-borne viral diseases in the past 20 years. Transmitted through the bite of Aedes mosquitoes, the clinical picture associated with these acute arbovirus infections, including Dengue (DENV), CHIKV and ZIKV, ranges from classical febrile illness to life-threatening disease. Whereas ZIKV and CHIKV-mediated infections have previously been recognized as relatively benign diseases, in contrast to Dengue fever, recent epidemic events have brought waves of increased morbidity and mortality leading to a serious public health problem. Although the host immune response plays a crucial role in controlling infections, it may also promote viral spread and immunopathology. Here, we review recent developments in our understanding of the immune response, with an emphasis on the early antiviral immune response mediated by natural killer cells and emphasize their Janus-faced effects in the control of arbovirus infection and pathogenesis. Improving our understanding knowledge on of the mechanisms that control viral infection is crucial in the current race against the globalization of arbovirus epidemics.