bluuebunny/crossref_metadata_2025 huggingface dataset:
Compensation of Limited Bandwidth and Nonlinearity for Coherent Transponder
Authors: Wang Qiang , Yue Yang , Anderson Jon
Published: April 2019

Coherent optical transponders are widely deployed in today’s long haul and metro optical networks using dense wavelength division multiplexing. To increase the data carrying capacity, the coherent transponder utilizes the high order modulation format and operates at a high baud rate. The limited bandwidth and the nonlinearity are two critical impairments for the coherent in-phase quadrature transmitter. These impairments can be mitigated by digital filters. However, to accurately determine the coefficients of these filters is difficult because the impairment from the limited bandwidth and the impairment from nonlinearity are coupled together. In this paper, we present a novel method to solve this problem. During the initial power-up, we apply a sinusoidal stimulus to the coherent IQ transmitter. We then scan the frequency and amplitude of the stimulus and monitor the output power. By curve-fitting with an accurate mathematical model, we determine the limited bandwidth, the nonlinearity, the power imbalance, and the bias point of the transponder simultaneously. Optimized coefficients of the digital filters are determined accordingly. Furthermore, we utilize a coherent IQ transponder and demonstrate that the limited bandwidth is improved by the finite impulse response filter, while nonlinearity is mitigated by the memoryless Volterra filter.
Comprehensive Serum Glycopeptide Spectra Analysis (CSGSA): A Potential New Tool for Early Detection of Ovarian Cancer
Authors: Hayashi Masaru , Matsuo Koji , Tanabe Kazuhiro , Ikeda Masae , Miyazawa Mariko , Yasaka Miwa , Machida Hiroko , Shida Masako , Imanishi Tadashi , Grubbs Brendan H. , Hirasawa Takeshi , Mikami Mikio
Published: April 2019

Objectives: To conduct a comprehensive glycopeptide spectra analysis of serum between cancer and non-cancer patients to identify early biomarkers of epithelial ovarian cancer (EOC). Methods: Approximately 30,000 glycopeptide peaks were detected from the digested serum glycoproteins of 39 EOC patients (23 early-stage, 16 advanced-stage) and 45 non-cancer patients (27 leiomyoma and ovarian cyst cases, 18 endometrioma cases) by liquid chromatography mass spectrometry (LC–MS). The differential glycopeptide peak spectra were analyzed to distinguish between cancer and non-cancer groups by employing multivariate analysis including principal component analysis (PCA), orthogonal partial least squares discriminant analysis (OPLS-DA) and heat maps. Results: Examined spectral peaks were filtered down to 2281 serum quantitative glycopeptide signatures for differentiation between ovarian cancer and controls using multivariate analysis. The OPLS-DA model using cross-validation parameters R2 and Q2 and score plots of the serum samples significantly differentiated the EOC group from the non-cancer control group. In addition, women with early-stage clear cell carcinoma and endometriomas were clearly distinguished from each other by OPLS-DA as well as by PCA and heat maps. Conclusions: Our study demonstrates the potential of comprehensive serum glycoprotein analysis as a useful tool for ovarian cancer detection.
Impact of Extrinsic and Intrinsic Hypoxia on Catecholamine Biosynthesis in Absence or Presence of Hif2α in Pheochromocytoma Cells
Authors: Bechmann Nicole , Poser Isabel , Seifert Verena , Greunke Christian , Ullrich Martin , Qin Nan , Walch Axel , Peitzsch Mirko , Robledo Mercedes , Pacak Karel , Pietzsch Jens , Richter Susan , Eisenhofer Graeme
Published: April 2019

Pheochromocytomas and paragangliomas (PPGLs) with activated pseudohypoxic pathways are associated with an immature catecholamine phenotype and carry a higher risk for metastasis. For improved understanding of the underlying mechanisms we investigated the impact of hypoxia and pseudohypoxia on catecholamine biosynthesis in pheochromocytoma cells naturally lacking Hif2α (MPC and MTT) or expressing both Hif1α and Hif2α (PC12). Cultivation under extrinsic hypoxia or in spheroid culture (intrinsic hypoxia) increased cellular dopamine and norepinephrine contents in all cell lines. To distinguish further between Hif1α- and Hif2α-driven effects we expressed Hif2α in MTT and MPC-mCherry cells (naturally lacking Hif2α). Presence of Hif2α resulted in similarly increased cellular dopamine and norepinephrine under hypoxia as in the control cells. Furthermore, hypoxia resulted in enhanced phosphorylation of tyrosine hydroxylase (TH). A specific knockdown of Hif1α in PC12 diminished these effects. Pseudohypoxic conditions, simulated by expression of Hif2α under normoxia resulted in increased TH phosphorylation, further stimulated by extrinsic hypoxia. Correlations with PPGL tissue data led us to conclude that catecholamine biosynthesis under hypoxia is mainly mediated through increased phosphorylation of TH, regulated as a short-term response (24–48 h) by HIF1α. Continuous activation of hypoxia-related genes under pseudohypoxia leads to a HIF2α-mediated phosphorylation of TH (permanent status).
Optimized AKS Primality Testing: A Fluctuation Theory Perspective
Authors: Tiwari Bhupendra , Kuipo Jude , Adeegbe Joshua , Marina Ninoslav
Published: April 2019

The AKS algorithm is an important breakthrough in showing that primality testing of an integer can be done in polynomial time. In this paper, we study the optimization of its runtime. Namely, given a finite cardinality set of alphabets of a deterministic polynomial runtime Turing machine and the number of strings of an arbitrary input integer whose primality is to be tested as the system parameters, we consider the randomized AKS primality testing function as the objective function. Under randomization of the system parameters, we have shown that there are definite signatures of the local and global instabilities in the AKS algorithm. We observe that instabilities occur at the extreme limits of the parameters. It is worth mentioning that Fermat’s little theorem and Chinese remaindering help with the determination of the underlying stability domains. On the other hand, in the realm of the randomization theory, our study offers fluctuation theory structures of the AKS primality testing of an integer through its maximum number of irreducible factors. Finally, our optimization theory analysis anticipates a class of real-world applications for future research and developments, including optimal online security, system optimization and its performance improvements, (de)randomization techniques, and beyond, e.g., polynomial time primality testing, identity testing, machine learning, scientific computing, coding theory, and other stimulating optimization problems in a random environment.
The Decoloration of Anionic and Cationic Dyes Using ZnO and ZnO-Cu2O
Authors: Dai Jiang Dong , Gan Luo , Zhang Hai Yan , Liu Chun Ming
Published: April 2019

ZnO and ZnO-Cu2O were grown on aluminum foam using hydrothermal method. Due to the positively charged sites on the surface, both ZnO and ZnO-Cu2O show higher adsorption capability towards anionic dyes, but poorer adsorption capability towards cationic dyes. The adsorption ability of ZnO-Cu2O is smaller than that of ZnO since there is a depletion layer at the interface. In order to decolorize cationic dyes, ZnO and ZnO-Cu2O are used as sono-catalyst with ultrasonic irradiation. The ZnO-Cu2O is better than ZnO in sono-catalysis decoloration of cationic dyes. This may be due to the enhanced piezoelectricity and electrochemical activity, as the free electrons in ZnO are reduced in the depletion layer.
The Polyextreme Ecosystem, Salar de Huasco at the Chilean Altiplano of the Atacama Desert Houses Diverse Streptomyces spp. with Promising Pharmaceutical Potentials
Authors: Cortés-Albayay Carlos , Silber Johanna , Imhoff Johannes F. , Asenjo Juan A. , Andrews Barbara , Nouioui Imen , Dorador Cristina
Published: April 2019

Salar de Huasco at the Chilean Altiplano of the Atacama Desert is considered a polyextreme environment, where solar radiation, salinity and aridity are extremely high and occur simultaneously. In this study, a total of 76 bacterial isolates were discovered from soil samples collected at two different sites in the east shoreline of Salar de Huasco, including H0 (base camp next to freshwater stream in the north part) and H6 (saline soils in the south part). All isolated bacteria were preliminarily identified using some of their phenotypic and genotypic data into the genera Streptomyces (86%), Nocardiopsis (9%), Micromonospora (3%), Bacillus (1%), and Pseudomonas (1%). Streptomyces was found dominantly in both sites (H0 = 19 isolates and H6 = 46 isolates), while the other genera were found only in site H0 (11 isolates). Based on the genotypic and phylogenetic analyses using the 16S rRNA gene sequences of all Streptomyces isolates, 18% (12 isolates) revealed <98.7% identity of the gene sequences compared to those in the publicly available databases and were determined as highly possibly novel species. Further studies suggested that many Streptomyces isolates possess the nonribosomal peptide synthetases-coding gene, and some of which could inhibit growth of at least two test microbes (i.e., Gram-positive and Gram-negative bacteria and fungi) and showed also the cytotoxicity against hepatocellular carcinoma and or mouse fibroblast cell lines. The antimicrobial activity and cytotoxicity of these Streptomyces isolates were highly dependent upon the nutrients used for their cultivation. Moreover, the HPLC-UV-MS profiles of metabolites produced by the selected Streptomyces isolates unveiled apparent differences when compared to the public database of existing natural products. With our findings, the polyextreme environments like Salar de Huasco are promising sources for exploring novel and valuable bacteria with pharmaceutical potentials.
Effects of Land Use Intensification on Avian Predator Assemblages: A Comparison of Landscapes with Different Histories in Northern Europe
Authors: Manton Michael , Angelstam Per , Naumov Vladimir
Published: April 2019

Land use and landcover change alter the ability of habitat networks to maintain viable species populations. While their effects on the quality, amount and patterns of landcover patches are commonly studied, how they affect ecological processes, such as predation on focal species remains neglected. This macroecological study tests the hypothesis that predator assemblages are affected by land use intensity linked to different socio-economic contexts. We measured the distribution and abundance of two avian predator groups (generalist corvid birds and specialist raptors), and proxy variables that mirror their food resources, at three spatial scales in northern Europe’s West and East. In total, we made 900 survey counts for avian predators and their resources in six landcover strata throughout five landscapes and analyzed their relationships. The abundance of omnivorous corvid birds was associated with the number of anthropogenic food resources. Thus, corvid birds were most common in the urban and agricultural landcovers, and where forest cover was low. Corvid bird abundance, and availability of their resources, increased with increasing land use intensity. Raptors were less abundant than corvid birds and most common in semi-natural grasslands. The number of raptor species increased with decreasing land use intensity. This study shows that the abundance and composition of avian predator species must be understood to maintain functional habitat networks.
Mechanism of Capacity Fading in the LiNi0.8Co0.1Mn0.1O2 Cathode Material for Lithium-Ion Batteries
Authors: Ahn Yong-keon , Jo Yong Nam , Cho Woosuk , Yu Ji-Sang , Kim Ki Jae
Published: April 2019

Understanding the capacity fading mechanism of the LiNi0.8Co0.1Mn0.1O2 (NCM811) cathode materials is crucial for achieving long-lasting lithium-ion batteries with high energy densities. In this study, we investigated the factors affecting the capacity fading of NCM811 during repeated cycling at high temperatures. We found that the change in the c-axis length during charging and discharging is the main cause of the formation and propagation of microcracks in the primary particles of NCM811. In addition, the electrolyte is decomposed on the microcrack surfaces and, consequently, by-products are formed on the particle surface, increasing the impedance and resulting in poor electronic and ionic connectivity between the primary particles of NCM811. In addition, the transition metals in the NCM811 cathode material are dissolved in the electrolyte from the newly formed microcrack surface between primary particles. Therefore, the electrolyte decomposition and transition metal dissolution on the newly formed surface are the major deteriorative effects behind the capacity fading in NCM811.
Some New Generalizations for Exponentially s-Convex Functions and Inequalities via Fractional Operators
Authors: Rashid Saima , Noor Muhammad Aslam , Noor Khalida Inayat , Akdemir Ahmet Ocak
Published: April 2019

The main objective of this paper is to obtain the Hermite–Hadamard-type inequalities for exponentially s-convex functions via the Katugampola fractional integral. The Katugampola fractional integral is a generalization of Riemann–Liouville fractional integral and Hadamard fractional integral. Some special cases and applications to special means are also discussed.
Cloning of pcB and pcA Gene from Gracilariopsis lemaneiformis and Expression of a Fluorescent Phycocyanin in Heterologous Host
Authors: Sun Deguang , Zang Xiaonan , Guo Yalin , Xiao Dongfang , Cao Xuexue , Liu Zhu , Zhang Feng , Jin Yuming , Shi Jiawei , Wang Zhendong , Li Rui , Yangzong Zhaxi
Published: April 2019

In order to study the assembly mechanism of phycocyanin in red algae, the apo-phycocyanin genes (pcB and pcA) were cloned from Gracilariopsis lemaneiformis. The full length of phycocyanin β-subunit (pcB) contained 519 nucleotides encoding a protein of 172 amino acids, and the full length of phycocyanin α-subunit(pcA) contained 489 nucleotides encoding a protein of 162 amino acids. Expression vector pACYCDuet-pcB-pcA was constructed and transformed into E. coli BL21 with pET-ho-pcyA (containing ho and pcyA gene to synthesize phycocyanobilin). The recombinant strain showed fluorescence activity, indicating the expression of optically active phycocyanin in E. coli. To further investigate the possible binding sites between phycocyanobilin and apo-phycocyanin, Cys-82 and Cys-153 of the β subunit and the Cys-84 of the α subunit were respectively mutated, and four mutants were obtained. All mutant strains had lower fluorescence intensity than the non-mutant strains, which indicated that these mutation sites could be the active binding sites between apo-phycocyanin and phycocyanobilin (PCB). This research provides a supplement for the comprehensive understanding of the assembly mechanism of optically active phycocyanin in red algae.
Computational Characterization of the mtORF of Pocilloporid Corals: Insights into Protein Structure and Function in Stylophora Lineages from Contrasting Environments
Authors: Banguera-Hinestroza Eulalia , Ferrada Evandro , Sawall Yvonne , Flot Jean-François
Published: April 2019

More than a decade ago, a new mitochondrial Open Reading Frame (mtORF) was discovered in corals of the family Pocilloporidae and has been used since then as an effective barcode for these corals. Recently, mtORF sequencing revealed the existence of two differentiated Stylophora lineages occurring in sympatry along the environmental gradient of the Red Sea (18.5 °C to 33.9 °C). In the endemic Red Sea lineage RS_LinB, the mtORF and the heat shock protein gene hsp70 uncovered similar phylogeographic patterns strongly correlated with environmental variations. This suggests that the mtORF too might be involved in thermal adaptation. Here, we used computational analyses to explore the features and putative function of this mtORF. In particular, we tested the likelihood that this gene encodes a functional protein and whether it may play a role in adaptation. Analyses of full mitogenomes showed that the mtORF originated in the common ancestor of Madracis and other pocilloporids, and that it encodes a transmembrane protein differing in length and domain architecture among genera. Homology-based annotation and the relative conservation of metal-binding sites revealed traces of an ancient hydrolase catalytic activity. Furthermore, signals of pervasive purifying selection, lack of stop codons in 1830 sequences analyzed, and a codon-usage bias similar to that of other mitochondrial genes indicate that the protein is functional, i.e., not a pseudogene. Other features, such as intrinsically disordered regions, tandem repeats, and signals of positive selection particularly in Stylophora RS_LinB populations, are consistent with a role of the mtORF in adaptive responses to environmental changes.
Senses of Place, Senses of Past: The Case of Antikythera and its Castle, Greece
Authors: Fouseki Kalliopi , Alexopoulos Georgios
Published: April 2019

This article explores local perceptions towards an archaeological site on the Greek island of Antikythera, known as ‘Castle’, within the context of recent calls for the development of the island through heritage tourism. As the identification of such perceptions is a fundamental step in tourism planning we will reflect on data gathered during an ethnographic study funded by the post-doctoral scheme of the Greek State Scholarship Foundation. Our purpose was to examine how local perceptions of the island and its landscape, as a whole, define the ways in which the archaeological ‘Castle’ of Antikythera is perceived. We observed that positive or negative attitudes towards the archaeology of the island are strongly interlinked with positive or negative feelings for the island in general. Since most studies focus on the role of heritage in shaping a sense of place, we hope that this article will offer a new insight into the role of place in shaping heritage perceptions. We also hope that the findings of the research will inform future decisions on tourism development and its impact (potential risks or opportunities) on the sense of place.
The Mortality Response to Absolute and Relative Temperature Extremes
Authors: Sheridan Scott C. , Lee Cameron C. , Allen Michael J.
Published: April 2019

While the impact of absolute extreme temperatures on human health has been amply studied, far less attention has been given to relative temperature extremes, that is, events that are highly unusual for the time of year but not necessarily extreme relative to a location’s overall climate. In this research, we use a recently defined extreme temperature event metric to define absolute extreme heat events (EHE) and extreme cold events (ECE) using absolute thresholds, and relative extreme heat events (REHE) and relative extreme cold events (RECE) using relative thresholds. All-cause mortality outcomes using a distributed lag nonlinear model are evaluated for the largest 51 metropolitan areas in the US for the period 1975–2010. Both the immediate impacts and the cumulative 20-day impacts are assessed for each of the extreme temperature event types. The 51 metropolitan areas were then grouped into 8 regions for meta-analysis. For heat events, the greatest mortality increases occur with a 0-day lag, with the subsequent days showing below-expected mortality (harvesting) that decreases the overall cumulative impact. For EHE, increases in mortality are still statistically significant when examined over 20 days. For REHE, it appears as though the day-0 increase in mortality is short-term displacement. For cold events, both relative and absolute, there is little mortality increase on day 0, but the impacts increase on subsequent days. Cumulative impacts are statistically significant at more than half of the stations for both ECE and RECE. The response to absolute ECE is strongest, but is also significant when using RECE across several southern locations, suggesting that there may be a lack of acclimatization, increasing mortality in relative cold events both early and late in winter.
Prospective Evaluation of Fidelity, Impact and Sustainability of Participatory Workplace Health Teams in Skilled Nursing Facilities
Authors: Kotejoshyer Rajashree , Zhang Yuan , Flum Marian , Fleishman Jane , Punnett Laura
Published: April 2019

Organizational features of work often pose obstacles to workforce health, and a participatory change process may address those obstacles. In this research, an intervention program sought to integrate occupational safety and health (OSH) with health promotion (HP) in three skilled nursing facilities. Three facilities with pre-existing HP programs served as control sites. The intervention was evaluated after 3–4 years through focus groups, interviews, surveys, and researcher observations. We assessed process fidelity in the intervention sites and compared the two groups on the scope of topics covered (integration), program impact, and medium-term sustainability. The intervention met with initial success as workers readily accepted and operationalized the concept of OSH/HP integration in all three intervention facilities. Process fidelity was high at first but diminished over time. At follow-up, team members in two intervention sites reported higher employee engagement and more attention to organizational issues. Two of the three control facilities remained status quo, with little OSH/HP integration. The intervention had limited but positive impact on the work environment and health climate: staff awareness and participation in activities, and organizational factors such as decision-making, respect, communication, and sharing of opinions improved slightly in all intervention sites. Resources available to the teams, management support, and changing corporate priorities affected potential program sustainability.
Risk Factors and Prediction of Leptospiral Seropositivity Among Dogs and Dog Handlers in Malaysia
Authors: Goh Soon Heng , Ismail Rosnah , Lau Seng Fong , Megat Abdul Rani Puteri Azaziah , Mohd Mohidin Taznim Begam , Daud Faiz , Bahaman Abdul Rani , Khairani-Bejo Siti , Radzi Rozanaliza , Khor Kuan Hua
Published: April 2019

This study determined the potential risk factors that may contribute to seropositivity among dogs and dog handlers from working dog and dog shelter institutions. Data was collected from dogs (n = 266) and dog handlers (n = 161) using a standardised guided questionnaire. Serum obtained from the dogs and dog handlers was tested using the microscopic agglutination test (MAT). A logistic regression analysis was used to predict leptospiral seropositivity of dogs and dog handlers based on potential risk factors. A total of 22.2% of dogs and 21.7% of dog handlers were seropositive. The significant predictors for the dogs’ seropositivity were presence of rats (OR = 4.61 (95% CI: 1.05, 20.33), p = 0.043) and shared common area (OR = 5.12 (95% CI: 1.94, 13.46), p = 0.001) within the organisation. Significant predictor for dog handler seropositivity was contact time with the dogs of more than six hours/day (OR = 3.28 (95% CI: 1.28, 8.40), p = 0.013) after controlling for the effect of other risk factors such as small mammal contact, rat infestation at home, flooding at housing area (within three months) and urban locality. The exposure to various disease sources identified poses risk to dogs and dog handlers. Risk could be reduced with adequate application of protection at work while handling dogs and thus limiting contact with these sources and reducing exposure to infection.
A Pilot Study to Test the Feasibility of a Home Mobility Monitoring System in Community-Dwelling Older Adults
Authors: Son Heesook , Kim Hyerang
Published: April 2019

Technology enables home-based personalized care through continuous, automated, real-time monitoring of a participant’s health condition and remote communication between health care providers and participants. Technology has been implemented in a variety of nursing practices. However, little is known about the use of home mobility monitoring systems in visiting nursing practice. Therefore, the current study tested the feasibility of a home mobility monitoring system as a supportive tool for monitoring daily activities in community-dwelling older adults. Daily mobility data were collected for 15 months via home-based mobility monitoring sensors among eight older adults living alone. Indoor sensor outputs were categorized into sleeping, indoor activities, and going out. Atypical patterns were identified with reference to baseline activity. Daily indoor activities were clearly differentiated by sensor outputs and discriminated atypical activity patterns. During the year of monitoring, a health-related issue was identified in a participant. Our findings indicate the feasibility of a home mobility monitoring system for remote, continuous, and automated assessment of a participant’s health-related mobility patterns. Such a system could be used as a supportive tool to detect and intervene in the case of problematic health issues.
The Effects of Motion Artifacts on Self-Avatar Agency
Authors: Koilias Alexandros , Mousas Christos , Anagnostopoulos Christos-Nikolaos
Published: April 2019

One way of achieving self-agency in virtual environments is by using a motion capture system and retargeting user’s motion to the virtual avatar. In this study, we investigated whether the self-agency is affected when motion artifacts appear on top of the baseline motion capture data assigned to the self-avatar. For this experiment, we implemented four artifacts: noise, latency, motion jump, and offset rotation of joints. The data provided directly from the motion capture system formed the baseline of the study. We developed three observation tasks to assess self-agency: self-observation, observation through a virtual mirror, and observation during locomotion. A questionnaire was adopted and used to capture the self-agency of participants. We analyzed the collected responses of participants to determine whether the motion artifacts significantly altered the participants’ sense of self-agency. The obtained results indicated that participants are not always sensitive to the motion artifacts assigned to the self-avatar, but the sense of self-agency is dependent on the observation task they were asked to perform. Implications for further research are discussed.
Reactive Heterobimetallic Complex Combining Divalent Ytterbium and Dimethyl Nickel Fragments
Authors: Wang Ding , Moutet Jules , Tricoire Maxime , Cordier Marie , Nocton Grégory
Published: April 2019

This article presented the synthesis and characterization of original heterobimetallic species combining a divalent lanthanide fragment and a divalent nickel center bridged by the bipyrimidine ligand, a redox-active ligand. X-ray crystal structures were obtained for the Ni monomer (bipym)NiMe2, 1, as well as the heterobimetallic dimer compounds, Cp*2Yb(bipym)NiMe2, 2, along with 1H solution NMR, solid-state magnetic data, and DFT calculations only for 1. The reactivity with CO was investigated on both compounds and the stoichiometric acetone formation is discussed based on kinetic and mechanistic studies. The key role of the lanthanide fragment was demonstrated by the relatively slow CO migratory insertion step, which indicated the stability of the intermediate.
Effects of Principal Stress Rotation on the Fluid-Induced Soil Response in a Porous Seabed
Authors: Li Zhengxu , Jeng Dong-Sheng , Zhu Jian-Feng , Zhao Hongyi
Published: April 2019

Principal stress rotation (PSR) is an important feature for describing the stress status of marine sediments subject to cyclic loading. In this study, a one-way coupled numerical model that combines the fluid model (for wave–current interactions) and the soil model (including the effect of PSR) was established. Then, the proposed model was incorporated into the finite element analysis procedure DIANA-SWANDYNE II with PSR effects incorporated and further validated by the experimental data available in the literature. Finally, the impact of PSR on the pore-water pressures and the resultant seabed liquefaction were investigated using the numerical model, and it was found that PSR had a significant influence on the seabed response to combined wave and current loading.
A Novel Route to Fabricate High-Performance 3D Printed Continuous Fiber-Reinforced Thermosetting Polymer Composites
Authors: Ming Yueke , Duan Yugang , Wang Ben , Xiao Hong , Zhang Xiaohui
Published: April 2019

Recently, 3D printing of fiber-reinforced composites has gained significant research attention. However, commercial utilization is limited by the low fiber content and poor fiber–resin interface. Herein, a novel 3D printing process to fabricate continuous fiber-reinforced thermosetting polymer composites (CFRTPCs) is proposed. In brief, the proposed process is based on the viscosity–temperature characteristics of the thermosetting epoxy resin (E-20). First, the desired 3D printing filament was prepared by impregnating a 3K carbon fiber with a thermosetting matrix at 130 °C. The adhesion and support required during printing were then provided by melting the resin into a viscous state in the heating head and rapidly cooling after pulling out from the printing nozzle. Finally, a powder compression post-curing method was used to accomplish the cross-linking reaction and shape preservation. Furthermore, the 3D-printed CFRTPCs exhibited a tensile strength and tensile modulus of 1476.11 MPa and 100.28 GPa, respectively, a flexural strength and flexural modulus of 858.05 MPa and 71.95 GPa, respectively, and an interlaminar shear strength of 48.75 MPa. Owing to its high performance and low concentration of defects, the proposed printing technique shows promise in further utilization and industrialization of 3D printing for different applications.
Effect of the Electric Field on the Distribution Law of Chloride Ions and Microstructure in Concrete with the Addition of Mineral Admixtures
Authors: Xie Xiaoli , Feng Qingge , Chen Zheng , Lu Wei
Published: April 2019

Migration testing of chloride under an electric field is a fast and effective method to determine the corrosion resistance of reinforced concrete against chloride. In this study, a series of admixture-involved (fly ash and slag) concrete specimens were produced for an accelerating chloride diffusion test in 3% NaCl solution under an electric field and natural chloride diffusion in 165 g/L NaCl solution under immersion conditions. Then, the chloride profile and pore structure of concretes aged 56 and 91 days were compared to investigate the effect of the electric field on chloride diffusion as well as the microstructure of the concrete. The results showed that, under accelerating electric field conditions, the degree to which chloride refined the internal pore structure of the concrete was weaker than that under natural immersion conditions. The applied electric field changed the pore structure inside the concrete, but it had little effect on the distribution of total, free, and bound chlorides and their mutual relationship. In addition, it is necessary to consider that the electric field effect on chloride migration varies with the concrete mix proportions.
Effect of Hot-Alkali Treatment on the Structure Composition of Jute Fabrics and Mechanical Properties of Laminated Composites
Authors: Wang Xue , Chang Lulu , Shi Xiaolong , Wang Lihai
Published: April 2019

In this study, jute fabrics/epoxy-laminated composites were fabricated via a simple and effective manual layering. Hot-alkali treatment was used to pretreat jute fabrics to improve their interfacial compatibility. The effects of hot-alkali treatment with five concentrations (2%, 4%, 6%, 8% and 10%) on the composition, crystallinity and surface morphology of jute fibers, were analyzed with the aids of Fourier transform infrared spectroscopy (FTIR), X-ray diffractometry (XRD), and the scanning electron microscope (SEM). The mechanical properties (tensile and flexural) of laminated composites, and the morphology of the tensile fracture surface, were analyzed. The results indicated that the crystallinity index (CI) and crystallite size (CS) of the cellulose in jute fibers were improved, and there were three stages for CI and CS with the increase of alkali concentrations. Hot-alkali treatment improved the mechanical properties of laminated composites, especially for the 6% NaOH-treated jute fabric reinforced. The tensile strength, flexural strength, tensile modulus and flexural modulus of 6% NaOH-treated fabrics reinforced composites were enhanced by 37.5%, 72.3%, 23.2% and 72.2%, respectively, as compared with those of untreated fabrics reinforced composites. The fiber pull-out and the gaps of the tensile fracture surface were reduced after hot-alkali treatment.
Three-Dimensional Nano-Morphology of Carbon Nanotube/Epoxy Filled Poly(methyl methacrylate) Microcapsules
Authors: Icduygu M. Galip , Asilturk Meltem , Yalcinkaya M. Akif , Hamidi Youssef K. , Altan M. Cengiz
Published: April 2019

The three-dimensional nano-morphology of poly(methyl methacrylate; PMMA) microcapsules filled with carbon nanotubes (CNTs) and epoxy resin were investigated by various microscopy methods, including a novel, laser scanning confocal microscopy (LSCM) method. Initially, PMMA microcapsules containing various amounts of CNTs were synthesized by a solvent evaporation method. Scanning electron microscopy analysis showed that pore-free, smooth-surface microcapsules formed with various types of core-shell morphologies. The average size of CNT/epoxy/PMMA microcapsules was shown to decrease from ~52 μm to ~15 μm when mixing speed during synthesis increased from 300 rpm to 1000 rpm. In general, the presence of CNTs resulted in slightly larger microcapsules and higher variations in size. Moreover, three-dimensional scans obtained from confocal microscopy revealed that higher CNT content increased the occurrence and size of CNT aggregates inside the microcapsules. Entrapped submicron air bubbles were also observed inside most microcapsules, particularly within those with higher CNT content.
Designing the Composition of Cement Stabilized Rammed Earth Using Artificial Neural Networks
Authors: Anysz Hubert , Narloch Piotr
Published: April 2019

Cement stabilized rammed earth (CRSE) is a sustainable, low energy consuming construction technique which utilizes inorganic soil, usually taken directly from the construction site, with a small addition of Portland cement as a building material. This technology is gaining popularity in various regions of the world, however, there are no uniform standards for designing the composition of the CSRE mixture. The main goal of this article is to propose a complete algorithm for designing CSRE with the use of subsoil obtained from the construction site. The article’s authors propose the use of artificial neural networks (ANN) to determine the proper proportions of soil, cement, and water in a CSRE mixture that provides sufficient compressive strength. The secondary purpose of the paper (supporting the main goal) is to prove that artificial neural networks are suitable for designing CSRE mixtures. For this purpose, compressive strength was tested on several hundred CSRE samples, with different particle sizes, cement content and water additions. The input database was large enough to enable the artificial neural network to produce predictions of high accuracy. The developed algorithm allows us to determine, using relatively simple soil tests, the composition of the mixture ensuring compressive strength at a level that allows the use of this material in construction.
Heat Source Characteristics of Ternary-Gas-Shielded Tandem Narrow-Gap GMAW
Authors: Cai Xiaoyu , Dong Bolun , Lin Sanbao , Murphy Anthony B. , Fan Chenglei , Yang Chunli
Published: April 2019

The characteristics of the welding heat source for tandem narrow-gap gas metal arc welding are examined for different ternary shielding gas (Ar-CO2-He) compositions. Results of previous calculations of arc properties for bead-on-plate geometry are adapted to the narrow-gap geometry to predict these characteristics. The heat source concentration factor decreases and the maximum heat flux density increases as the helium content increases, which leads to an increased welding heat efficiency. Addition of CO2 up to around 10% also increases the heat efficiency. When the CO2 content exceeds 10%, the heat source concentration factor increases significantly and the heat efficiency decreases. The shielding gas composition also affects the heat source distribution. The heat source characteristics are applied to a computational fluid dynamic model of the weld pool to predict the weld shape, and the predictions are verified by experiment. The results indicate that the appropriate addition of helium to the shielding gas can increase the heat transferred to the peripheral regions of the arc and increase the sidewall penetration.
The Usual Suspects 2019: of Chips, Droplets, Synthesis, and Artificial Cells
Authors: Eilenberger Christoph , Spitz Sarah , Bachmann Barbara , Ehmoser Eva , Ertl Peter , Rothbauer Mario
Published: April 2019

Synthetic biology aims to understand fundamental biological processes in more detail than possible for actual living cells. Synthetic biology can combat decomposition and build-up of artificial experimental models under precisely controlled and defined environmental and biochemical conditions. Microfluidic systems can provide the tools to improve and refine existing synthetic systems because they allow control and manipulation of liquids on a micro- and nanoscale. In addition, chip-based approaches are predisposed for synthetic biology applications since they present an opportune technological toolkit capable of fully automated high throughput and content screening under low reagent consumption. This review critically highlights the latest updates in microfluidic cell-free and cell-based protein synthesis as well as the progress on chip-based artificial cells. Even though progress is slow for microfluidic synthetic biology, microfluidic systems are valuable tools for synthetic biology and may one day help to give answers to long asked questions of fundamental cell biology and life itself.
Editorial for the Special Issue on MEMS Accelerometers
Authors: Rasras Mahmoud , Elfadel Ibrahim (Abe) M. , Ngo Ha Duong
Published: April 2019

Micro-Electro-Mechanical Systems (MEMS) devices are widely used for motion, pressure, light, and ultrasound sensing applications [...]
A Facile Strategy for Visualizing and Modulating Droplet-Based Microfluidics
Authors: Gao Zehang , Peng Huo , Zhu Minjie , Wu Lei , Jia Chunping , Zhou Hongbo , Zhao Jianlong
Published: April 2019

In droplet-based microfluidics, visualizing and modulating of droplets is often prerequisite. In this paper, we report a facile strategy for visualizing and modulating high-throughput droplets in microfluidics. In the strategy, by modulating the sampling frequency of a flash light with the droplet frequency, we are able to map a real high frequency signal to a low frequency signal, which facilitates visualizing and feedback controlling. Meanwhile, because of not needing synchronization signals, the strategy can be directly implemented on any droplet-based microfluidic chips. The only cost of the strategy is an additional signal generator. Moreover, the strategy can catch droplets with frequency up to several kilohertz, which covers the range of most high-throughput droplet-based microfluidics. In this paper, the principle, setup and procedure were introduced. Finally, as a demonstration, the strategy was also implemented in a miniaturized picoinjector in order to monitor and control the injection dosage to droplets. We expect that this facile strategy supplies a low-cost yet effective imaging system that can be easily implemented in miniaturized microfluidic systems or general laboratories.
Occurrence and Function of the Na+-Translocating NADH:Quinone Oxidoreductase in Prevotella spp.
Authors: Deusch Simon , Bok Eva , Schleicher Lena , Seifert Jana , Steuber Julia
Published: April 2019

Strictly anaerobic Prevotella spp. are characterized by their vast metabolic potential. As members of the Prevotellaceae family, they represent the most abundant organisms in the rumen and are typically found in monogastrics such as pigs and humans. Within their largely anoxic habitats, these bacteria are considered to rely primarily on fermentation for energy conservation. A recent study of the rumen microbiome identified multiple subunits of the Na+-translocating NADH:quinone oxidoreductase (NQR) belonging to different Prevotella spp. Commonly, the NQR is associated with biochemical energy generation by respiration. The existence of this Na+ pump in Prevotella spp. may indicate an important role for electrochemical Na+ gradients in their anaerobic metabolism. However, detailed information about the potential activity of the NQR in Prevotella spp. is not available. Here, the presence of a functioning NQR in the strictly anaerobic model organism P. bryantii B14 was verified by conducting mass spectrometric, biochemical, and kinetic experiments. Our findings propose that P. bryantii B14 and other Prevotella spp. retrieved from the rumen operate a respiratory NQR together with a fumarate reductase which suggests that these ruminal bacteria utilize a sodium motive force generated during respiratory NADH:fumarate oxidoreduction.
Analysis of Cellulose and Lignocellulose Materials by Raman Spectroscopy: A Review of the Current Status
Authors: Agarwal Umesh P.
Published: April 2019

This review is a summary of the Raman spectroscopy applications made over the last 10 years in the field of cellulose and lignocellulose materials. This paper functions as a status report on the kinds of information that can be generated by applying Raman spectroscopy. The information in the review is taken from the published papers and author’s own research—most of which is in print. Although, at the molecular level, focus of the investigations has been on cellulose and lignin, hemicelluloses have also received some attention. The progress over the last decade in applying Raman spectroscopy is a direct consequence of the technical advances in the field of Raman spectroscopy, in particular, the application of new Raman techniques (e.g., Raman imaging and coherent anti-Stokes Raman or CARS), novel ways of spectral analysis, and quantum chemical calculations. On the basis of this analysis, it is clear that Raman spectroscopy continues to play an important role in the field of cellulose and lignocellulose research across a wide range of areas and applications, and thereby provides useful information at the molecular level.
Combination of Lactobacillus acidophilus and Bifidobacterium animalis subsp. lactis Shows a Stronger Anti-Inflammatory Effect than Individual Strains in HT-29 Cells
Authors: Li Sing-Chung , Hsu Wei-Fang , Chang Jung-Su , Shih Chun-Kuang
Published: April 2019

Inflammatory bowel disease (IBD) is an emerging health problem associated with the dysregulation of the intestinal immune system and microbiome. Probiotics are able to reduce inflammatory responses in intestinal epithelial cells (IECs). However, entire signaling pathways and the interaction between different probiotics have not been well-documented. This study was designed to investigate the anti-inflammatory effects and mechanisms of single and combined probiotics. HT-29 cells were induced by lipopolysaccharide (LPS) and tumor necrosis factor (TNF)-α, treated with Lactobacillus acidophilus, Bifidobacterium animalis subsp. lactis or their combination and analyzed for inflammation-related molecules. Both L. acidophilus and B. animalis subsp. lactis reduced interleukin (IL)-8 secretion and the expressions of phosphorylated p65 nuclear factor-kappa B (p-p65 NF-κB), phosphorylated p38 mitogen-activated protein kinase (p-p38 MAPK), vascular cell adhesion molecule-1 (VCAM-1) and cyclooxygenase-2 (COX-2), while they increased toll-like receptor 2 (TLR2) expression. L. acidophilus did not decrease intercellular adhesion molecule-1 (ICAM-1) but enhanced the inhibitory efficacy of B. animalis subsp. lactis. Combined probiotics showed the best anti-inflammatory activity. These results suggest that L. acidophilus and B. animalis subsp. lactis may exert a potent anti-inflammatory effect through modulating TLR2-mediated NF-κB and MAPK signaling pathways in inflammatory IECs. Both strains, especially their combination, may be novel adjuvants for IBD therapy.
Olive Leaf Extract (OleaVita) Suppresses Inflammatory Cytokine Production and NLRP3 Inflammasomes in Human Placenta
Authors: Kaneko Yasuaki , Sano Michiya , Seno Kotomi , Oogaki Yuka , Takahashi Hironori , Ohkuchi Akihide , Yokozawa Miki , Yamauchi Ken , Iwata Hisataka , Kuwayama Takehito , Shirasuna Koumei
Published: April 2019

The placenta is essential for pregnancy and produces both pro-inflammatory and anti-inflammatory cytokines. Excessive production of inflammatory cytokines, involving interleukin-1β (IL-1β), IL-6, and IL-8, from placental tissues is associated with pregnancy complications. Olive leaf extract has several health benefits, including anti-inflammatory functions. OleaVita is a new commercial olive leaf extract; it is hypothesized to suppress placental inflammation. In human placental tissue culture, OleaVita treatment inhibited the secretion of inflammatory cytokines and NF-κB p65 protein expression. OleaVita also suppressed toll-like receptor ligands-induced IL-1β secretion in human placental tissues. IL-1β is regulated by the NLRP3 inflammasomes, a pivotal regulator of various diseases. OleaVita significantly decreased NLRP3 and pro-IL-1β protein expression, suggesting that it has an inhibitory effect on NLRP3 inflammasome activation. Thus, OleaVita is beneficial as an inhibitor of inflammation and NLRP3 inflammasome activation, and may be used as a supplement for the treatment and prevention of inflammatory diseases.
Blackcurrant (Ribes nigrum) Extract Exerts an Anti-Inflammatory Action by Modulating Macrophage Phenotypes
Authors: Lee Yoojin , Lee Ji-Young
Published: April 2019

Macrophages are polarized into different phenotypes depending on tissue microenvironment where they reside. In obesity-associated inflammation, M1-type macrophages are predominant in the inflamed tissue, exerting pro-inflammatory responses. Our previous studies demonstrate that blackcurrant consumption attenuates hepatic inflammation and lipopolysaccharide-stimulated inflammatory responses of splenocytes in obese mice. In this study, we determined whether blackcurrant modulates macrophage phenotypes to exert its anti-inflammatory action. Mouse bone marrow-derived macrophages (BMDM) and human THP-1 macrophages were polarized into M1 macrophages in the presence or absence of blackcurrant extract (BCE). BCE repressed M1 polarization of both murine and human macrophages. Also, to gain insight into the role of blackcurrant metabolites produced in vivo in the regulation of macrophage phenotypes, BMDM were treated with serum obtained from lean or obese mice fed blackcurrant. While serum from lean mice fed blackcurrant did not exert either anti-inflammatory actions or suppressive effects on M1 polarization, serum from obese mice fed blackcurrant reduced the expression of pro-inflammatory genes in BMDM. Our data demonstrate that BCE suppresses M1 polarization, with reduced pro-inflammatory responses. Moreover, this study suggests that blackcurrant metabolites may not exert their anti-inflammatory effect directly by altering macrophage phenotypes, but possibly by inhibiting the production of obesity-associated inflammatory factors.