bluuebunny/crossref_metadata_2025 huggingface dataset:
On Soft Rough Topology with Multi-Attribute Group Decision Making
Authors: Riaz Muhammad , Smarandache Florentin , Firdous Atiqa , Fakhar Atiqa
Published: January 2019

Rough set approaches encounter uncertainty by means of boundary regions instead of membership values. In this paper, we develop the topological structure on soft rough set ( SR -set) by using pairwise SR -approximations. We define SR -open set, SR -closed sets, SR -closure, SR -interior, SR -neighborhood, SR -bases, product topology on SR -sets, continuous mapping, and compactness in soft rough topological space ( SRTS ). The developments of the theory on SR -set and SR -topology exhibit not only an important theoretical value but also represent significant applications of SR -sets. We applied an algorithm based on SR -set to multi-attribute group decision making (MAGDM) to deal with uncertainty.
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H-ψH-Multivalued Contractive Mappings and Related Results in Complete Metric Spaces with an Application
Authors: Dhawan Pooja , Jain Kapil , Kaur Jatinderdeep
Published: January 2019

In the present article, the notion of α H- ψ H-multivalued contractive type mappings is introduced and some fixed point results in complete metric spaces are studied. These theorems generalize Nadler’s (Multivalued contraction mappings, Pac. J. Math., 30, 475–488, 1969) and Suzuki-Kikkawa’s (Three fixed point theorems for generalized contractions with constants in complete metric spaces, Nonlinear Anal., 69, 2942–2949, 2008) results that exist in the literature. The effectiveness of the obtained results has been verified with the help of some comparative examples. Moreover, a homotopy result has been presented as an application.
The Incidence of Tetrodotoxin and Its Analogs in the Indian Ocean and the Red Sea
Authors: Tamele Isidro José , Silva Marisa , Vasconcelos Vitor
Published: January 2019

Tetrodotoxin (TTX) is a potent marine neurotoxin with bacterial origin. To date, around 28 analogs of TTX are known, but only 12 were detected in marine organisms, namely TTX, 11-oxoTTX, 11-deoxyTTX, 11-norTTX-6(R)-ol, 11-norTTX-6(S)-ol, 4-epiTTX, 4,9-anhydroTTX, 5,6,11-trideoxyTTX, 4-CysTTX, 5-deoxyTTX, 5,11-dideoxyTTX, and 6,11-dideoxyTTX. TTX and its derivatives are involved in many cases of seafood poisoning in many parts of the world due to their occurrence in different marine species of human consumption such as fish, gastropods, and bivalves. Currently, this neurotoxin group is not monitored in many parts of the world including in the Indian Ocean area, even with reported outbreaks of seafood poisoning involving puffer fish, which is one of the principal TTX vectors know since Egyptian times. Thus, the main objective of this review was to assess the incidence of TTXs in seafood and associated seafood poisonings in the Indian Ocean and the Red Sea. Most reported data in this geographical area are associated with seafood poisoning caused by different species of puffer fish through the recognition of TTX poisoning symptoms and not by TTX detection techniques. This scenario shows the need of data regarding TTX prevalence, geographical distribution, and its vectors in this area to better assess human health risk and build effective monitoring programs to protect the health of consumers in Indian Ocean area.
Purification and Characterization of a Novel Pentadecapeptide from Protein Hydrolysates of Cyclina sinensis and Its Immunomodulatory Effects on RAW264.7 Cells
Authors: Li Wei , Ye Shengwang , Zhang Zhuangwei , Tang Jiachao , Jin Huoxi , Huang Fangfang , Yang Zuisu , Tang Yunping , Chen Yan , Ding Guofang , Yu Fangmiao
Published: January 2019

In the present study, peptide fractions of Cyclina sinensis hydrolysates, with molecular weight (MW) < 3 kDa and highest relative proliferation rate of murine macrophage cell line RAW 264.7, were purified by a series of chromatographic purification methods, to obtain peptide fractions with immunomodulatory activity. The amino acid sequence of the peptide was identified to be Arg-Val-Ala-Pro-Glu-Glu-His-Pro-Val-Glu-Gly-Arg-Tyr-Leu-Val (RVAPEEHPVEGRYLV) with MW of 1750.81 Da, and the novel pentadecapeptide (named SCSP) was synthesized for subsequent immunomodulatory activity experiments. Results showed the SCSP enhanced macrophage phagocytosis, increased productions of nitric oxide (NO), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β), and up-regulated the protein level of inducible nitric oxide synthase (iNOS), nuclear factor κB (NF-κB), and NOD-like receptor protein 3 (NLRP3) in RAW 264.7 cells. Furthermore, the expression of inhibitor of nuclear factor κB-α (IκB-α) was down-regulated. These findings suggest that SCSP might stimulate macrophage activities by activating the NF-κB signaling pathway and can be used as a potential immunomodulatory agent in functional food or medicine.
New Drugs from the Sea: Pro-Apoptotic Activity of Sponges and Algae Derived Compounds
Authors: Ercolano Giuseppe , De Cicco Paola , Ianaro Angela
Published: January 2019

Natural compounds derived from marine organisms exhibit a wide variety of biological activities. Over the last decades, a great interest has been focused on the anti-tumour role of sponges and algae that constitute the major source of these bioactive metabolites. A substantial number of chemically different structures from different species have demonstrated inhibition of tumour growth and progression by inducing apoptosis in several types of human cancer. The molecular mechanisms by which marine natural products activate apoptosis mainly include (1) a dysregulation of the mitochondrial pathway; (2) the activation of caspases; and/or (3) increase of death signals through transmembrane death receptors. This great variety of mechanisms of action may help to overcome the multitude of resistances exhibited by different tumour specimens. Therefore, products from marine organisms and their synthetic derivates might represent promising sources for new anticancer drugs, both as single agents or as co-adjuvants with other chemotherapeutics. This review will focus on some selected bioactive molecules from sponges and algae with pro-apoptotic potential in tumour cells.
Structural Elucidation of a Novel Lipooligosaccharide from the Cold-Adapted Bacterium OMVs Producer Shewanella sp. HM13
Authors: Casillo Angela , Di Guida Rossella , Carillo Sara , Chen Chen , Kamasaka Kouhei , Kawamoto Jun , Kurihara Tatsuo , Corsaro Maria Michela
Published: January 2019

Shewanella sp. HM13 is a cold-adapted Gram-negative bacterium isolated from the intestine of a horse mackerel. It produces a large amount of outer membrane vesicles (OMVs), which are particles released in the medium where the bacterium is cultured. This strain biosynthesizes a single major cargo protein in the OMVs, a fact that makes Shewanella sp. HM13 a good candidate for the production of extracellular recombinant proteins. Therefore, the structural characterization of the components of the vesicles, such as lipopolysaccharides, takes on a fundamental role for understanding the mechanism of biogenesis of the OMVs and their applications. The aim of this study was to investigate the structure of the oligosaccharide (OS) isolated from Shewanella sp. HM13 cells as the first step for a comparison with that from the vesicles. The lipooligosaccharide (LOS) was isolated from dry cells, purified, and hydrolyzed by alkaline treatment. The obtained OS was analyzed completely, and the composition of fatty acids was obtained by chemical methods. In particular, the OS was investigated in detail by 1H and 13C NMR spectroscopy and MALDI-TOF mass spectrometry. The oligosaccharide was characterized by the presence of a residue of 8-amino-3,8-dideoxy-manno-oct-2-ulosonic acid (Kdo8N) and of a d,d-heptose, with both residues being identified in other oligosaccharides from Shewanella species.
New 1,2,4-Oxadiazole Nortopsentin Derivatives with Cytotoxic Activity
Authors: Cascioferro Stella , Attanzio Alessandro , Di Sarno Veronica , Musella Simona , Tesoriere Luisa , Cirrincione Girolamo , Diana Patrizia , Parrino Barbara
Published: January 2019

New analogs of nortopsentin, a natural 2,4-bis(3′-indolyl)imidazole alkaloid, in which the central imidazole ring of the natural lead was replaced by a 1,2,4-oxadiazole moiety, and in which a 7-azaindole portion substituted the original indole moiety, were efficiently synthesized. Among all derivatives, prescreened against the HCT-116 colon rectal carcinoma cell line, the two most active compounds were selected and further investigated in different human tumor cells showing IC50 values in the micromolar and submicromolar range. Flow cytometric analysis of propidium iodide-stained MCF-7 cells demonstrated that both the active derivatives caused cell cycle arrest in the G0–G1 phase. The cell death mechanism induced by the compounds was considered to be apoptotic by measuring the exposure of phosphatidylserine to the outer membrane and observed morphological evaluation using acridine orange/ethidium bromide double staining. Moreover, further tested on intestinal normal-like differentiated Caco-2 cell line, they exhibited preferential toxicity towards cancer cells.
Collagen Extraction Optimization from the Skin of the Small-Spotted Catshark (S. canicula) by Response Surface Methodology
Authors: Blanco María , Vázquez José Antonio , Pérez-Martín Ricardo I. , G. Sotelo Carmen
Published: January 2019

The small-spotted catshark is one of the most abundant elasmobranchs in the Northeastern Atlantic Ocean. Although its landings are devoted for human consumption, in general this species has low commercial value with high discard rates, reaching 100% in some European fisheries. The reduction of post-harvest losses (discards and by-products) by promotion of a full use of fishing captures is one of the main goals of EU fishing policies. As marine collagens are increasingly used as alternatives to mammalian collagens for cosmetics, tissue engineering, etc., fish skins represent an excellent and abundant source for obtaining this biomolecule. The aim of this study was to analyze the influence of chemical treatment concentration, temperature and time on the extractability of skin collagen from this species. Two experimental designs, one for each of the main stages of the process, were performed by means of Response Surface Methodology (RSM). The combined effect of NaOH concentration, time and temperature on the amount of collagen recovered in the first stage of the collagen extraction procedure was studied. Then, skins treated under optimal NaOH conditions were subjected to a second experimental design, to study the combined effect of AcOH concentration, time and temperature on the collagen recovery by means of yield, amino acid content and SDS-PAGE characterization. Values of independent variables maximizing collagen recovery were 4 °C, 2 h and 0.1 M NaOH (pre-treatment) and 25 °C, 34 h and 1 M AcOH (collagen extraction).
Experimental Mixed-Gas Permeability, Sorption and Diffusion of CO2-CH4 Mixtures in 6FDA-mPDA Polyimide Membrane: Unveiling the Effect of Competitive Sorption on Permeability Selectivity
Authors: Genduso Giuseppe , Ghanem Bader , Pinnau Ingo
Published: January 2019

The nonideal behavior of polymeric membranes during separation of gas mixtures can be quantified via the solution-diffusion theory from experimental mixed-gas solubility and permeability coefficients. In this study, CO2-CH4 mixtures were sorbed at 35 °C in 4,4′-(hexafluoroisopropylidene)diphthalic dianhydride (6FDA)-m-phenylenediamine (mPDA)—a polyimide of remarkable performance. The existence of a linear trend for all data of mixed-gas CO2 versus CH4 solubility coefficients—regardless of mixture concentration—was observed for 6FDA-mPDA and other polymeric films; the slope of this trend was identified as the ratio of gas solubilities at infinite dilution. The CO2/CH4 mixed-gas solubility selectivity of 6FDA-mPDA and previously reported polymers was higher than the equimolar pure-gas value and increased with pressure from the infinite dilution value. The analysis of CO2-CH4 mixed-gas concentration-averaged effective diffusion coefficients of equimolar feeds showed that CO2 diffusivity was not affected by CH4. Our data indicate that the decrease of CO2/CH4 mixed-gas diffusion, and permeability selectivity from the pure-gas values, resulted from an increase in the methane diffusion coefficient in mixtures. This effect was the result of an alteration of the size sieving properties of 6FDA-mPDA as a consequence of CO2 presence in the 6FDA-mPDA film matrix.
Two-Phase Numerical Modeling of Grade Intermixing in a Steelmaking Tundish
Authors: Siddiqui Md Irfanul Haque , Kim Man-Hoe
Published: January 2019

The sequential casting of slabs is a major trend in the steel industry where steel quality is the most important factor. The operating parameters have the most influence on mixing phenomenon apart from the design and shapes of the tundish and its furniture. Moreover, in industrial practice, the bath height in tundish varied with time when the ladle is changed. In the present work, the numerical simulation has been carried out to study the effect of residual volume and outflow (throughput) rate on the mixing phenomenon inside the tundish. A transient, three-dimensional two-phase model using the Volume of Fluid (VOF) method and Level Set interface tracking method has been used to investigate the intermixed grade steel formation. A comparison of the two interface tracking schemes, i.e., Geo-reconstruct and Modified HRIC (High-Resolution Interface Capturing Scheme) has also been presented. The results obtained through numerical simulation has been compared with experimental results. In a later section, the results showed that residual volume has a significant effect on the grade mixing. The mixing phenomenon in tundish is considerably influenced by the advance-pouring box (APB). Further, the outflow rate of tundish has little impact on the grade intermixing phenomenon.
Numerical Investigation of Secondary Deformation Mechanisms on Plastic Deformation of AZ31 Magnesium Alloy Using Viscoplastic Self-Consistent Model
Authors: Lian Yong , Hu Li , Zhou Tao , Yang Mingbo , Zhang Jin
Published: January 2019

Uniaxial tension and compression of AZ31 magnesium alloy were numerically investigated via the viscoplastic self-consistent (VPSC) model to shed a light on the effect of secondary deformation mechanisms (prismatic  slip, pyramidal  slip, and { 10 1 ¯ 1 } contraction twinning) during plastic deformation. The method adopted in the present study used different combinations of deformation mechanisms in the VPSC modeling. In terms of the pyramidal  slip, it served as the first candidate for sustaining the extra plastic strain during the plastic deformation. The improvement of activity in the pyramidal  slip contributed to the increase in the mechanical response and the splitting of pole densities in { 0002 } pole figure during uniaxial tension. As for the prismatic  slip, its increasing activity was not only conducive to the improvement of flow stress in mechanical response, but also responsible for the splitting of pole densities in { 0002 } pole figure during uniaxial compression. With respect to the { 10 1 ¯ 1 } contraction twinning, it had a negligible influence on the plastic deformation of AZ31 magnesium alloy in terms of the mechanical response as well as the slip and the twinning activities. However, it is better to include the { 10 1 ¯ 1 } contraction twinning in the VPSC modeling to more accurately predict the texture evolution.
Joining Aluminium Alloy 5A06 to Stainless Steel 321 by Vaporizing Foil Actuators Welding with an Interlayer
Authors: Su Shan , Chen Shujun , Mao Yu , Xiao Jun , Vivek Anupam , Daehn Glenn
Published: January 2019

Direct aluminium–stainless steel joints are difficult to create by the vaporized foil actuator welding (VFAW) method because brittle intermetallic compounds (IMCs) tend to form along the interface. The use of an interlayer as a transition layer between the two materials with vast difference in hardness and ductility was proposed as a solution to reduce the formation of the IMCs. In this work, VFAW was used to successfully weld sheet aluminium alloy 5A06 to stainless steel 321 with a 3003 aluminium alloy interlayer. Input energy levels of 6 kJ, 8 kJ, 10 kJ, and 12 kJ were used and as a trend, higher energy inputs resulted in higher impact velocities, larger weld area, and better mechanical properties. In lap-shear and peel testing, all samples failed at the interface of the interlayer and target. At 10 kJ energy input, flyer velocities up to 935 m/s, lap-shear peak load of 44 kN, and peel load of 2.15 kN were achieved. Microstructure characterization and element distribution were performed, and the results show a wavy pattern created between the flyer and interlayer which have similar properties, and the interface between the interlayer and target was dominated by element diffusion and IMCs identified mainly as FeAl3 and FeAl. The results demonstrate VFAW is a suitable joining method for dissimilar metals such as aluminium alloy and stainless steel, which has a broad and significant application prospect in aerospace and chemical industry.
Effect of T6 Heat Treatment on Microstructure and Hardness of Nanosized Al2O3 Reinforced 7075 Aluminum Matrix Composites
Authors: Zhang Peng-Xiang , Yan Hong , Liu Wei , Zou Xiu-Liang , Tang Bin-Bing
Published: January 2019

In this study, 7075 aluminum matrix composites reinforced with 1.5 wt.% nanosized Al2O3 were fabricated by ultrasonic vibration. The effect of T6 heat treatment on both microstructure and hardness of nanosized Al2O3 reinforced 7075 (Al2O3np/7075) composites were studied via scanning electron microscopy, energy dispersive X-ray spectrometry, X-ray diffraction, transmission electron microscopy, and hardness tests. The Mg(Zn,Cu,Al)2 phases gradually dissolved into the matrix under solution treatment at 480 °C for 5 h. However, the morphology and size of Al7Cu2Fe phases remained unchanged due to their high melting points. Furthermore, the slenderness strips MgZn2 phases precipitated under aging treatment at 120 °C for 24 h. Compared to as-cast composites, the hardness of the sample under T6 heat treatment was increased ~52%. The strengthening mechanisms underlying the achieved hardness of composites are revealed.
Investigation of Chip Deformation and Breaking with a Staggered Teeth BTA Tool in Deep Hole Drilling
Authors: Li Xu-Bo , Zheng Jian-Ming , Li Yan , Kong Ling-Fei , Shi Wei-Chao , Guo Bian
Published: January 2019

The problem of chip breaking and evacuation is the key point of staggered teeth boring and trepanning association (BTA) drilling. The factors that influence chip breaking with staggered teeth BTA deep hole drilling are analyzed by using the chip bending deformation mechanism for chip formation and flow through the rake face and chip breaker. This study investigated the distribution and variation of chip deformation and breaking along drilling conditions, with respect to drilling radius, drilling process parameters, tool wear, and chip breaker geometric parameters. The results show that the tool-chip contact length is about 1.65 times the chip thickness in staggered teeth BTA drilling. The cutting radius of the teeth has a considerable influence on the chip thickness. Compared with the drilling speed, the feed has a greater impact on chip deformation and breaking, and the chip thickness and strain increase with increased feed. Increased drilling depth and tooth wear aggravates the friction state between the chip and the rake face, augments chip thickness and tool-chip contact length, and increases the chip’s strain increment. As the width of chip breaker decreases and the height increases, the chip strain increases and the breaking conditions are improved.
Effects of Fe2O3 on Reduction Process of Cr-Containing Solid Waste Self-Reduction Briquette and Relevant Mechanism
Authors: Wu Tuo , Zhang Yanling , Zhao Zheng , Yuan Fang
Published: January 2019

High-temperature quench method, scanning electron microscope-energy dispersive spectroscopy (SEM-EDS), and thermodynamic analysis were adopted to study the effects of Fe2O3 on reduction process of Cr-containing solid waste self-reduction briquette (Cr-RB). Moreover, the relevant mechanism was also studied. The results clearly showed that the addition of Fe2O3 decreased the chromium-iron ratio (Cr/(Fe + Cr)) of Cr-RB itself and promoted the reduction of chrome oxide in the Cr-containing solid wastes such as stainless steel slag and dust. A large number of Fe-C alloy droplets generated in the lower temperature could decrease the activity of reduced chromium by in situ dissolution and the reduction of Cr-oxide was accelerated. Rapid separation of metal and slag could be achieved at a relatively lower temperature, which was very beneficial to the efficient recovery of Cr. Finally, the corresponding mechanism diagram was presented.
Experimental Investigation of Solidification in the Cast Mold with a Consumable Cooler Introduced Inside
Authors: Niu Ran , Li Baokuan , Liu Zhongqiu , Bu Lifu , Li Xianglong , Yang Xiao , Tsukihashi Fumitaka
Published: January 2019

The microstructure is of great significance for the stability and mechanical performance of the cast slab. Recently, an innovative technology of feeding a consumable cooler into the mold has been proposed to improve the internal quality of castings. But the mechanism is not clear. In the present work, a water-cooled transparent laboratory equipment was set up and solidification of NH4Cl-70%H2O solution was studied to observe the in-situ growth and sedimentation of crystals. The experiments were conducted with and without adding a consumable cooler. Morphology variation of the solidification structure was visualized and temperature distribution during the process was recorded. Results show that introduction of the consumable cooler significantly reduces the temperature of the central zone. Melting of the consumable cooler can supply a large quantity of equiaxed crystals, which prevent the growth of columnar dendrites and thereby promote columnar to equiaxed transition (CET). Moreover, the enhanced convection shows an effect of grain refinement.
Assessment of l-Asparaginase Pharmacodynamics in Mouse Models of Cancer
Authors: Horvath Thomas D. , Chan Wai Kin , Pontikos Michael A. , Martin Leona A. , Du Di , Tan Lin , Konopleva Marina , Weinstein John N. , Lorenzi Philip L.
Published: January 2019

l-asparaginase (ASNase) is a metabolism-targeted anti-neoplastic agent used to treat acute lymphoblastic leukemia (ALL). ASNase’s anticancer activity results from the enzymatic depletion of asparagine (Asn) and glutamine (Gln), which are converted to aspartic acid (Asp) and glutamic acid (Glu), respectively, in the blood. Unfortunately, accurate assessment of the in vivo pharmacodynamics (PD) of ASNase is challenging because of the following reasons: (i) ASNase is resilient to deactivation; (ii) ASNase catalytic efficiency is very high; and (iii) the PD markers Asn and Gln are depleted ex vivo in blood samples containing ASNase. To address those issues and facilitate longitudinal studies in individual mice for ASNase PD studies, we present here a new LC-MS/MS bioanalytical method that incorporates rapid quenching of ASNase for measurement of Asn, Asp, Gln, and Glu in just 10 µL of whole blood, with limits of detection (s:n ≥ 10:1) estimated to be 2.3, 3.5, 0.8, and 0.5 µM, respectively. We tested the suitability of the method in a 5-day, longitudinal PD study in mice and found the method to be simple to perform with sufficient accuracy and precision for whole blood measurements. Overall, the method increases the density of data that can be acquired from a single animal and will facilitate optimization of novel ASNase treatment regimens and/or the development of new ASNase variants with desired kinetic properties.
Demonstration of Fin-Tunnel Field-Effect Transistor with Elevated Drain
Authors: Kim Jang Hyun , Kim Hyun Woo , Kim Garam , Kim Sangwan , Park Byung-Gook
Published: January 2019

In this paper, a novel tunnel field-effect transistor (TFET) has been demonstrated. The proposed TFET features a SiGe channel, a fin structure and an elevated drain to improve its electrical performance. As a result, it shows high-level ON-state current (ION) and low-level OFF-state current (IOFF); ambipolar current (IAMB). In detail, its ION is enhanced by 24 times more than that of Si control group and by 6 times more than of SiGe control group. The IAMB can be reduced by up to 900 times compared with the SiGe control group. In addition, technology computer-aided design (TCAD) simulation is performed to optimize electrical performance. Then, the benchmarking of ON/OFF current is also discussed with other research group’s results.
Stability of a Dumbbell Micro-Swimmer
Authors: Ishikawa Takuji
Published: January 2019

A squirmer model achieves propulsion by generating surface squirming velocities. This model has been used to analyze the movement of micro-swimmers, such as microorganisms and Janus particles. Although squirmer motion has been widely investigated, motions of two connected squirmers, i.e., a dumbbell squirmer, remain to be clarified. The stable assembly of multiple micro-swimmers could be a key technology for future micromachine applications. Therefore, in this study, we investigated the swimming behavior and stability of a dumbbell squirmer. We first examined far-field stability through linear stability analysis, and found that stable forward swimming could not be achieved by a dumbbell squirmer in the far field without the addition of external torque. We then investigated the swimming speed of a dumbbell squirmer connected by a short rigid rod using a boundary element method. Finally, we investigated the swimming stability of a dumbbell squirmer connected by a spring. Our results demonstrated that stable side-by-side swimming can be achieved by pullers. When the aft squirmer was a strong pusher, fore and aft swimming were stable and swimming speed increased significantly. The findings of this study will be useful for the future design of assembled micro-swimmers.
Heat Transport of Electrokinetic Flow in Slit Soft Nanochannels
Authors: Wang Zehua , Jian Yongjun
Published: January 2019

Soft nanochannels are defined as nanochannels with a polyelectrolyte layer (PEL) on the rigid walls. In the present study, the thermal transport properties of the fluids through slit soft nanochannels are investigated under the combined influences of pressure-driven and streaming potential. Based on the analytical solutions of electric potential and velocity distributions, a dimensionless temperature of electrolyte solution in soft nanochannels is obtained by resolving the energy equation. Then, a finite difference method is used to compute the energy equation and test the validity of the analytical solution. Results show that the temperature increases with the decrease of dimensionless velocity and the heat transfer rate for rigid nanochannel are higher than that for the soft one. Moreover, we find the total entropy generation decreases with the increases of the ratio Kλ of the electrical double layer (EDL) thickness in PEL to the EDL thickness on the solid wall.
Non-Invasive Quantification of the Growth of Cancer Cell Colonies by a Portable Optical Coherence Tomography
Authors: Tsai Meng-Tsan , Huang Bo-Huei , Yeh Chun-Chih , Lei Kin Fong , Tsang Ngan-Ming
Published: January 2019

Investigation of tumor development is essential in cancer research. In the laboratory, living cell culture is a standard bio-technology for studying cellular response under tested conditions to predict in vivo cellular response. In particular, the colony formation assay has become a standard experiment for characterizing the tumor development in vitro. However, quantification of the growth of cell colonies under a microscope is difficult because they are suspended in a three-dimensional environment. Thus, optical coherence tomography (OCT) imaging was develop in this study to monitor the growth of cell colonies. Cancer cell line of Huh 7 was used and the cells were applied on a layer of agarose hydrogel, i.e., a non-adherent surface. Then, cell colonies were gradually formed on the surface. The OCT technique was used to scan the cell colonies every day to obtain quantitative data for describing their growth. The results revealed the average volume increased with time due to the formation of cell colonies day-by-day. Additionally, the distribution of cell colony volume was analyzed to show the detailed information of the growth of the cell colonies. In summary, the OCT provides a non-invasive quantification technique for monitoring the growth of the cell colonies. From the OCT images, objective and precise information is obtained for higher prediction of the in vivo tumor development.
Tunable Fiber Laser with High Tuning Resolution in C-band Based on Echelle Grating and DMD Chip
Authors: Li Jinliang , Chen Xiao , Dai Dezheng , Gao Yunshu , Lv Min , Chen Genxiang
Published: January 2019

The tunable fiber laser with high tuning resolution in the C-band is proposed and demonstrated based on a digital micromirror device (DMD) chip and an echelle grating. The laser employs a DMD as a programmable wavelength filter and an echelle grating with high-resolution features to design a cross-dispersion optical path to achieve high-precision tuning. Experimental results show that wavelength channels with 3 dB-linewidth less than 0.02 nm can be tuned flexibly in the C-band and the wavelength tuning resolution is as small as 0.036 nm. The output power fluctuation is better than 0.07 dB, and the wavelength shift is below 0.013 nm in 1 h at room temperature.
Editorial for the Special Issue on Glassy Materials Based Microdevices
Authors: Righini Giancarlo C. , Righini Nicoletta
Published: January 2019

Glassy materials, i [...]
Silver Nanowire Ink for Flexible Circuit on Textiles
Authors: Du Dexi , Yang Xing , Yang Yonglan , Zhao Yuzhen , Wang Yuehui
Published: January 2019

Low cost electronics implemented in textiles could pave the way to a fully new generation of smart products in the fields of healthcare, sport, fashion, and safety. Although many methods have found their way into the market, many problems still need to be solved and much progress has to be made to enable the commercial exploitation of such products. In this paper, silver nanowires of 60–100 nm in diameter and 8–15 μm in length were achieved by the polyol solvothermal method, and aqueous silver nanowire conductive inks were prepared with the synthesized silver nanowires as the conductive phase, in the presence of polyaniline, guar, and hydrochloric acid. The conductive inks were printed on cotton fabric substrate by screen printing process. The effects of the amount of silver nanowires, layers of coating, and treatment temperature on the microstructure and electrical properties of samples were investigated by scanning electron microscopy and the four-point probe method. The results show that the conductivity and densification of the samples increased with increased amount of silver nanowires, layers of coating, and treatment temperature. The heat treatment helped to improve densification of the silver nanowires and conductivity of the sample. The resistance of the samples increased after bending due to loosening of the overlap between the silver nanowires.
A Theory for Energy-Optimized Operation of Self-Adaptive Vibration Energy Harvesting Systems with Passive Frequency Adjustment
Authors: Mösch Mario , Fischerauer Gerhard
Published: January 2019

Self-adaptive vibration energy harvesting systems vary their resonance frequency automatically to better exploit changing environmental conditions. The energy required for the adjustment is taken from the energy storage of the harvester module. The energy gained by an adjustment step has to exceed the energy expended on it to justify the adjustment. A smart self-adaptive system takes this into account and operates in a manner that maximizes the energy output. This paper presents a theory for the optimal operation of a vibration energy harvester with a passive resonance-frequency adjustment mechanism (one that only requires energy for the adjustment steps proper, but not during the hold phases between the steps). Several vibration scenarios are considered to derive a general guideline. It is shown that there exist conditions under which a narrowing of the adjustment bandwidth improves the system characteristics. The theory is applied to a self-adaptive energy harvesting system based on electromagnetic transduction with narrowband resonators. It is demonstrated that the novel optimum mode of operation increases the energy output by a factor of 3.6.
Exposure to Aspergillus in Home and Healthcare Facilities’ Water Environments: Focus on Biofilms
Authors: Richardson Malcolm , Rautemaa-Richardson Riina
Published: January 2019

Aspergillus conida are ubiquitous in the environment, including freshwater, water for bathing, and in drinking water. Vulnerable patients and those suffering from allergic diseases are susceptible to aspergillosis. Avoidance of Aspergillus is of paramount importance. Potential outbreaks of aspergillosis in hospital facilities have been described where the water supply has been implicated. Little is known regarding the risk of exposure to Aspergillus in water. How does Aspergillus survive in water? This review explores the biofilm state of Aspergillus growth based on recent literature and suggests that biofilms are responsible for the persistence of Aspergillus in domestic and healthcare facilities’ water supplies.
Expression and Purification of Chemokine MIP-3α (CCL20) through a Calmodulin-Fusion Protein System
Authors: Ramamourthy Gopal , Arias Mauricio , Nguyen Leonard T. , Ishida Hiroaki , Vogel Hans J.
Published: January 2019

Human macrophage inflammatory protein 3α (MIP-3α), also known as CCL20, is a 70 amino acid chemokine that selectively binds and activates chemokine receptor 6 (CCR6). This chemokine is responsible for inducing the migration of immature dendritic cells, effector, or memory T-cells, and B-cells. Moreover, the MIP-3α protein has been shown to display direct antimicrobial, antiviral and antiprotozoal activities. Because of the potential therapeutic uses of this protein, the efficient production of MIP-3α is of great interest. However, bacterial recombinant production of the MIP-3α protein has been limited by the toxicity of this extremely basic protein (pI 9.7) toward prokaryotic cells, and by solubility problems during expression and purification. In an attempt to overcome these issues, we have investigated the bacterial recombinant expression of MIP-3α by using several common expression and fusion tags, including 6× histidine (His), small ubiquitin modifier protein (SUMO), thioredoxin (TRX), ketosteroid isomerase (KSI), and maltose binding protein (MBP). We have also evaluated a recently introduced calmodulin (CaM)-tag that has been used for the effective expression of many basic antimicrobial peptides (AMPs). Here, we show that the CaM fusion tag system effectively expressed soluble MIP-3α in the cytoplasm of Escherichia coli with good yields. Rapid purification was facilitated by the His-tag that was integrated in the CaM-fusion protein system. Multidimensional nuclear magnetic resonance (NMR) studies demonstrated that the recombinant protein was properly folded, with the correct formation of disulfide bonds. In addition, the recombinant MIP-3α had antibacterial activity, and was shown to inhibit the formation of Pseudomonas aeruginosa biofilms.
Salinity and Temperature Influence Growth and Pigment Production in the Marine-Derived Fungal Strain Talaromyces albobiverticillius 30548
Authors: Venkatachalam Mekala , Gérard Léa , Milhau Cathie , Vinale Francesco , Dufossé Laurent , Fouillaud Mireille
Published: January 2019

Marine-derived fungi that inhabit severe changing environments have gained increasing interest for their ability to produce structurally unique natural products. Fungi belonging to the Talaromyces and the close Penicillium genera are among the most promising microbes for bioactive compound production, including colored metabolites. Coupling pigment producing capability with bioactive effectiveness would be a valuable challenge in some specific fields such as dyeing, cosmeceutical, or food industries. In this sense, Talaromyces albobiverticillius 30548, a red pigment producing strain, has been isolated from the marine environment of Reunion Island, Indian Ocean. In this research, we analyzed the effect of temperatures (21–27 °C) and salinity levels (0–9%) on fungal growth and pigment production. Maximum pigment yield was obtained in non-salted media, when cultured at 27 °C after 10 days of submerged fermentation in PDB. However, maximum dry biomass production was achieved at stressed condition with 9% sea salts concentrated media at the same temperature. The results indicate that salinity of the culture media positively influences the growth of the biomass. Inversely, pigment production decreases with increase in salinity over 6%. Color coordinates of secreted pigments were expressed in CIELAB color system. The hue angles (h°) ranged from red to yellow colors. This indicated that the color distribution of fungal pigments depends on the salinity in the culture media. This study emphasizes the impact of abiotic stress (salt and temperature) on the growth and metabolome of marine-derived fungal strains.
SNP and SCAR Markers for Specific Discrimination of Antler-Shaped Ganoderma lucidum
Authors: Kwon O-Chul , Lee Chang-Soo , Park Young-Jin
Published: January 2019

In this study we identified single nucleotide polymorphism (SNP) and sequence characteristic amplification region (SCAR) markers for specific identification of antler-shaped Ganoderma lucidum strains. When the partial mitochondrial SSU rDNA gene sequence of various antler- and kidney-shaped G. lucidum strains were analyzed and aligned, an SNP was found only in the antler-shaped G. lucidum strain at position 456 bp. In addition, this SNP of antler-shaped strains was digested by HinfI restriction enzyme. We further analyzed the polymorphism of various G. lucidum strains by random amplified polymorphic DNA (RAPD) analysis. In RAPD analysis, we isolated and sequenced a fragment, specific for antler-shaped G. lucidum strains. Based on this specific fragment sequence, two sets of specific primer pairs for antler-shaped G. lucidum strains were designed. PCR analysis revealed that two specific bands were observed only from antler-shaped strains. These two molecular markers will be helpful for identification of morphological characteristics of G. lucidum.
Fabrication and Characterization of AlGaN-Based UV LEDs with a ITO/Ga2O3/Ag/Ga2O3 Transparent Conductive Electrode
Authors: Wang Hong , Zhou Quanbin , Liang Siwei , Wen Rulian
Published: January 2019

We fabricated a complex transparent conductive electrode (TCE) based on Ga2O3 for AlGaN-based ultraviolet light-emitting diodes. The complex TCE consists of a 10 nm ITO, a 15 nm Ga2O3, a 7 nm Ag, and a 15 nm Ga2O3, forming a ITO/Ga2O3/Ag/Ga2O3 multilayer. The metal layer embedded into Ga2O3 and the thin ITO contact layer improves current spreading and electrode contact properties. It is found that the ITO/Ga2O3/Ag/Ga2O3 multilayer can reach a 92.8% transmittance at 365 nm and a specific contact resistance of 10−3 Ω·cm2 with suitable annealing conditions.
Dynamically Tunable Light Absorbers as Color Filters Based on Electrowetting Technology
Authors: Wu Jun , Du Yaqiong , Xia Jun , Zhang Tong , Lei Wei , Wang Baoping
Published: January 2019

A device that uses the electrowetting fluid manipulation technology to realize the reversible and dynamical modulation of the local surface plasmon resonance is invented. By varying the electrowetting voltage, the distribution of fluids media surrounding the grating structure get changed accordingly, causing the modulation of the plasmonic resonance peak. The simulation results indicated that three primary colors, that are cyan, magenta and yellow (CMY) can be respectively reflected through selecting suitable structural parameters. More importantly, for the first time, the invented fluid-based devices have exhibited fine-tuning characteristics for each primary color. Finally, the device has been proved to have a large color gamut range in the Commission International De L’E’clairage (CIE) 1931 color space.
Switchable Photonic Nanojet by Electro-Switching Nematic Liquid Crystals
Authors: Du Bintao , Xia Jun , Wu Jun , Zhao Jian , Zhang Hao
Published: January 2019

This paper first presents a switchable photonic nanojet (PNJ) generated by a polystyrene (PS) microsphere immersed in nematic liquid crystals (NLCs). The PNJ is switched by applying external voltage, which originates from the refractive index change in the surrounding medium caused by the field-induced realignment of liquid crystal molecules. By tuning the refractive index of NLCs larger or smaller than that of the PS microsphere, the PNJ can be switched off or on. Moreover, we present an optimization study to seek a better electric energy focusing property of the PNJ. Our results reveal that the switchability of PNJ can be optimized by applying a shorter incident wavelength, a double-layer microsphere, and a PS ellipsoid. The full width at half-maximum (FWHM) generated by the PS ellipsoid is narrower than that generated by the microsphere with a shorter incident wavelength. The intensity contrast of the PS ellipsoid is higher than that of the double-layer microsphere. As a whole, the switchability of PNJ can be best optimized by a PS ellipsoid. This should open the way for the development of integrated photonic devices.
A Novel Gold Calreticulin Nanocomposite Based on Chitosan for Wound Healing in a Diabetic Mice Model
Authors: Hernández Martínez Sara Paola , Rivera González Teodoro Iván , Franco Molina Moisés Armides , Bollain y Goytia Juan José , Martínez Sanmiguel Juan José , Zárate Triviño Diana Ginette , Rodríguez Padilla Cristina
Published: January 2019

The development of new nanomaterials to promote wound healing is rising, because of their topical administration and easy functionalization with molecules that can improve and accelerate the process of healing. A nanocomposite of gold nanoparticles (AuNPs) functionalized with calreticulin was synthetized and evaluated. The ability of the nanocomposite to promote proliferation and migration was determined in vitro, and in vivo wound healing was evaluated using a mice model of diabetes established with streptozotocin (STZ). In vitro, the nanocomposite not affect the cell viability and the expression of proliferating cell nuclear antigen (PCNA). Moreover, the nanocomposite promotes the clonogenicity of keratinocytes, endothelial cells, and fibroblasts, and accelerates fibroblast migration. In vivo, mice treated with the nanocomposite presented significantly faster wound healing. The histological evaluation showed re-epithelization and the formation of granular tissue, as well as an increase of collagen deposition. Therefore, these results confirm the utility of AuNPs–calreticulin nanocomposites as potential treatment for wound healing of diabetic ulcers.
Pesticide Encapsulation at the Nanoscale Drives Changes to the Hydrophobic Partitioning and Toxicity of an Active Ingredient
Authors: Slattery Matthew , Harper Bryan , Harper Stacey
Published: January 2019

Given the costs associated with designing novel active ingredients, new formulations focus on the use of other ingredients to modify existing formulations. Nanosized encapsulated pesticides offer a variety of enhanced features including controlled release and improved efficacy. Despite the presence of nanosized capsules in current-use pesticide formulations, the analytical and toxicological implications of encapsulation are uncertain. To explore this issue quantitatively, we fractionated the capsules of a commercially available encapsulated insecticide formulation (γ-cyhalothrin active ingredient) into two size ranges: a large fraction (LF), with an average hydrodynamic diameter (HDD) of 758 nm, and a small fraction (SF), with an average HDD of 449 nm. We developed a novel extraction method demonstrating a time-dependent inhibition of γ-cyhalothrin from capsules for up to 48 h. An acute immobilization test with a freshwater macroinvertebrate (Ceriodaphnia dubia) revealed that the SF was significantly more toxic than both the LF and the free γ-cyhalothrin treatment (EC50 = 0.18 µg/L, 0.57 µg/L, and 0.65 µg/L, respectively). These findings highlight that encapsulation of γ-cyhalothrin mitigates hydrophobic partitioning in a time-dependent manner and influences toxicity in a size-dependent manner. Recognizing the analytical and toxicological nuances of various nanosized capsules can contribute to innovation in pesticide formulations and may lead to more comprehensive pesticide regulation.
Conservation of Intronic Sequences in Vertebrate Mitochondrial Solute Carrier Genes (Zebrafish, Chicken, Mouse and Human)
Authors: Calvello Rosa , Cianciulli Antonia , Mitolo Vincenzo , Porro Annalisa , Panaro Maria Antonietta
Published: January 2019

The conservation of intronic sequences was studied in the mitochondrial solute carrier (SLC25A*) genes of Zebrafish, Chicken, Mouse and Human. These genes are homologous and the coding sequences have been well conserved throughout Vertebrates, but the corresponding intronic sequences have been extensively re-edited. However, significant segments of Zebrafish introns are conserved in Chicken, Mouse and Human in carriers SLC25A3, SLC25A21, SLC25A25, SLC25A26, and SLC25A36; Chicken intron segments are conserved in Mouse or Human in three additional carriers, namely SLC25A12, SLC25A13, and SLC25A29. Thus, a quota of the intronic sequences of Euteleostomi has been transferred (through Sarcopterygii) to Birds and (through Sarcopterygii and ancestral Mammals) to Mouse and Human. The degree of conservation of Euteleostomi-derived sequences is low and quite similar in Chicken, Mouse and Human (0.23–0.27%). The overall degree of conservation of Sarcopterygii-derived sequences in Mammals is higher, and it is significantly higher in Human than in Mouse (4.4% and 3.2%, respectively). Some of the conserved intronic sequences of SLC25A3, SLC25A21, SLC25A25, and SLC25A29 are exonized in some transcript variants of Zebrafish, Chicken, Mouse, and Human and, with minor nucleotide changes, in other Birds or Mammals.