bluuebunny/crossref_metadata_2025 huggingface dataset:
Visible-Light-Driven Photocatalytic Fuel Cell with an Ag-TiO2 Carbon Foam Anode for Simultaneous 4-Chlorophenol Degradation and Energy Recovery
Authors: Fu Shaozhu , Deng Beiqi , Ma Dongmei , Cheng Hanqing , Dong Shuangshi
Published: May 2018

Photocatalytic fuel cells (PFCs) are a sustainable technology with application in waste water treatment, in which energy is obtained from the photocatalytic degradation of organic pollutants. However, the application of PFCs is limited by the photoanode, in particular its low efficiency for treating recalcitrant pollutants. In this study, a double chamber PFC reactor was constructed. Visible-light-driven Ag-TiO2 photocatalyst supported carbon foam was used as the anode and platinum was used as the cathode. 4-Chlorophenol (4-CP) was used as a model pollutant in the cation chamber to investigate the efficiency of pollutant degradation and power generation. The effects of the electrolyte type and solution pH on the 4-CP degradation and power production were investigated. The results showed that 32.6% of 4-CP was degraded by the PFC in 6 h. Na2SO4 was the optimum electrolyte and had the least side effects on the degradation of 4-CP when compared with NaCl, NaHCO3 and NaH2PO4. The optimum pH range was 6.4–8.4 when sodium sulfate was used as the electrolyte. The power density was approximately 36.0 mW/m2 under the above experimental conditions.
The Drivers and Barriers of Renewable Energy Applications and Development in Uganda: A Review
Authors: Fashina Adebayo , Mundu Mustafa , Akiyode Oluwole , Abdullah Lookman , Sanni Dahiru , Ounyesiga Living
Published: May 2018

Following the increasing global awareness of the dangers posed by the present state of climate change, many countries such as Uganda have adapted long-term plans for a transition to decarbonised economies. A major strategy for decarbonisation is to replace fossil fuels with renewable energy (RE) sources as the fundamental energy source. Uganda has substantial RE resources for the provision of energy services and production, yet these resources remain untapped. It is therefore crucial that the use of these abundant resources should be heightened. This paper examines and discusses the potential and current RE utilization and development in Uganda from the perspective of sustainable development. The status of the different RE resources and their application/utilization, including details of existing projects in the country, are carefully explored and discussed. The possible drivers for a huge advancement of RE applications and development in Uganda are also discussed before elucidating the major barriers and challenges faced by the energy sector as regards RE. Measures and policies required to facilitate the utilization of RE in Uganda are proposed. These evidence-based policies could guide the delivery of affordable and sustainable energy solutions for all by 2030 in Uganda.
Kinetic Research on the Curing Reaction of Hydroxyl-Terminated Polybutadiene Based Polyurethane Binder System via FT-IR Measurements
Authors: Guo Jiahu , Chai Tao , Liu Yucun , Cui Jianlan , Ma Hui , Jing Suming , Zhong Lunchao , Qin Shengdong , Wang Guodong , Ren Xiang
Published: May 2018

Polyurethane binder systems based on hydroxyl-terminated polybutadiene (HTPB) possess several superior properties such as superior adhesion, high solid-loading capacity, outstanding mechanical performance, etc. They have been widely used in coatings and adhesives as well as in medical and military industries. The cure reaction between hydroxyl-terminated polybutadiene (HTPB) and diisocyanates plays a key role in the properties of final products as well as the adjustment of process parameters. FT-IR spectroscopy is applied to investigate the kinetics of the curing reaction of HTPB and isophorone diisocyanate (IPDI) in the presence of a low toxic and low viscosity catalyst, stannous isooctoate (TECH). The concentrations of the isocyanate groups (NCO) characterized by FT-IR during the cure reaction with respect to time were recorded at different temperatures and at constant stoichiometric ratio Rn[NCO]/n[OH] = 1.0. The kinetic parameters, i.e., activation energy (Ea), pre-exponential factor (A), activation enthalpy (ΔH) and activation entropy (ΔS) were determined. In addition, the curing process and mechanism of the HTPB-IPDI reaction are discussed.
Laser Cladding of Embedded Sensors for Thermal Barrier Coating Applications
Authors: Zhang Yanli , Mack Daniel , Mauer Georg , Vaßen Robert
Published: May 2018

The accurate real-time monitoring of surface or internal temperatures of thermal barrier coatings (TBCs) in hostile environments presents significant benefits to the efficient and safe operation of gas turbines. A new method for fabricating high-temperature K-type thermocouple sensors on gas turbine engines using coaxial laser cladding technology has been developed. The deposition of the thermocouple sensors was optimized to provide minimal intrusive features to the TBC, which is beneficial for the operational reliability of the protective coatings. Notably, this avoids a melt pool on the TBC surface. Sensors were deposited onto standard yttria-stabilized zirconia (7–8 wt % YSZ) coated substrates; subsequently, they were embedded with second YSZ layers by the Atmospheric Plasma Spray (APS) process. Morphology of cladded thermocouples before and after embedding was optimized in terms of topography and internal homogeneity, respectively. The dimensions of the cladded thermocouple were in the order of 200 microns in thickness and width. The thermal and electrical response of the cladded thermocouple was tested before and after embedding in temperatures ranging from ambient to approximately 450 °C in a furnace. Seebeck coefficients of bared and embedded thermocouples were also calculated correspondingly, and the results were compared to that of a commercial standard K-type thermocouple, which demonstrates that laser cladding is a prospective technology for manufacturing microsensors on the surface of or even embedded into functional coatings.
Shelf Life Assessment of Fresh Poultry Meat Packaged in Novel Bionanocomposite of Chitosan/Montmorillonite Incorporated with Ginger Essential Oil
Authors: Souza Victor , Pires João , Vieira Érica , Coelhoso Isabel , Duarte Maria , Fernando Ana
Published: May 2018

Active packaging incorporated with natural extracts is a promising technology to extend shelf life of perishable food. Therefore, this study aimed to produce a bionanocomposite based on chitosan reinforced with sodium montmorillonite (MMT) and incorporated with ginger essential oil (GEO). In vitro activity was assessed through migration assay and antimicrobial study against foodborne bacteria. Phenolic compounds were diffused within 48 h of contact, and retained some of their antioxidant activity. Films demonstrated antimicrobial activity against both Gram-positive and -negative bacteria tested. The effect on the shelf life of fresh poultry meat was determined on samples wrapped in the biopolymers and stored under refrigeration for 15 days, through physicochemical and microbiological analyses. Compared to unwrapped poultry meat, samples wrapped in the bionanocomposites showed a reduction in microorganisms count of 1.2–2.6 log CFU/g, maintained color and pH values and thiobarbituric acid reactive substances (TBARS) index increased at a lower rate, extending fresh poultry meat shelf life. The incorporation of GEO enhanced the biopolymer activity, by reducing lipid oxidation and microbiological growth of the poultry meat. In contrast, reinforcement with MMT imprisoned the active compounds in the polymeric chain, hindering its activity. In conclusion, the bionanocomposites tested represent promising substitutes to commercial and unsustainable plastic films.
An Analysis of Effect of CO2 Laser Treatment on Carbon Fibre Fabric
Authors: Liou Yu-de , Chau Kam-hong , Hui Chi-yuen , He Ju-liang , Lam Yin-ling , Kan Chi-wai
Published: May 2018

The colour of carbon fibre fabric is black which limits its aesthetic properties. CO2 laser has been used for cutting carbon fibres. The impact of CO2 laser treatment to modify the surface of carbon fibre fabric is investigated in this work. Different combinations of laser process parameters, i.e., pixel time (110, 120, 130, 140, 150, 160, 170, 180, 190 and 200 µs, with 10 µs intervals) and resolution (70, 80, 90 and 100 dpi (dots per inch), with 10 dpi intervals), were used for treating carbon fibre fabric surface. Since the laser process is a surface treatment, contact angle measurement was used for evaluating the wetting property imparted after laser processing. The resistivity of the laser-treated carbon fibre fabric was measured to evaluate any effect on the original electrical property of the carbon fibre fabric. Moreover, surface morphology and functionality of laser-treated carbon fibre fabric were assessed by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy-attenuated total internal reflectance (FTIR-ATR), respectively. SEM assessment was to examine the physical change in the carbon fibre surface after laser processing. On the other hand, the FTIR-ATR measurement can help to evaluate the chemical change in the carbon fibre surface after laser processing.
The Agent-Based Model and Simulation of Sexual Selection and Pair Formation Mechanisms
Authors: Dreżewski Rafał
Published: May 2018

In this paper, the agent-based simulation model of sexual selection and pair formation mechanisms is proposed. Sexual selection is a mechanism that occurs when the numbers of individuals of both sexes are almost identical, while reproduction costs for one of the sexes are much higher. The mechanism of creating pairs allows individuals to form stable, reproducing pairs. Simulation experiments carried out using the proposed agent-based model, and several fitness landscapes were aimed at verifying whether sexual selection and the mechanism of pair formation can trigger sympatric speciation and whether they can promote and maintain population diversity. Experiments were mainly focused on the mechanism of pair formation and its impact on speciation and population diversity. Results of conducted experiments show that sexual selection can start speciation processes and maintain the population diversity. The mechanism of creating pairs, when it occurs along with sexual selection, has a significant impact on the course of speciation and maintenance of population diversity.
Research on Double-Fed Induction Generator Low Voltage Ride Through Based on Double Braking Resistors Using Fuzzy Control
Authors: Dong Hao , Wu Hongbin , Pan Jing , Chen Yu , Xu Bin
Published: May 2018

The stator side of a double-fed induction generator (DFIG) is directly connected to the grid, so the DFIG is sensitive to a voltage drop caused by power system faults. A double resistors braking method based on fuzzy control is proposed to improve the performance of low-voltage ride through (LVRT) in this paper. Based on the mathematical model of DFIG, it analyzes the function of a series dynamical braking resistor (SDBR) theoretically. The series impedance value of the SDBR is determined by the variation of the rotor’s open circuit voltage, the voltage and current of the stator and the rotor, and also the heat capacity of the SDBR. In order to improve the LVRT capability of a DFIG under different fault grads, a double series resistors braking mode is presented. Through adopting a fuzzy control strategy, double series resistor switching is implemented. With the example system, the correctness and validity of the proposed method is verified.
Direct-Lyapunov-Based Control Scheme for Voltage Regulation in a Three-Phase Islanded Microgrid with Renewable Energy Sources
Authors: Kordkheili Hadi Hosseini , Banejad Mahdi , Kalat Ali Akbarzadeh , Pouresmaeil Edris , Catalão João P. S.
Published: May 2018

In this paper, the local control structure of a microgrid is partially modified by a Lyapunov-based controller. This controller is derived based on direct Lyapunov stability theory (DLST) in order to calculate proper switching functions for the stable operation of the local controller as well as proper local performance of each inverter-based distributed generation (DG) unit. The main contribution is the use of DLST-based controller in a hierarchical primary control structure along with a DC-side voltage regulator. A current-based droop controller is also introduced along with a voltage harmonic compensation technique. The control limits of droop equations are calculated based on steady-state and dynamic capability curve as well as voltage-frequency ellipse curve. The effect of the variations of voltages and circuit parameters on the capability curves are also investigated and the microgrid (MG) steady-state operation area is obtained. In the proposed method, the DC-voltage variations are regulated by an additional voltage control loop based on a current reference correction signal. The above-mentioned approaches are derived thoroughly with mathematical equations. The effectiveness of the designed controllers is verified by a MATLAB/SIMULINK simulation platform (Matlab/Simulink R2014a, Mathworks, Inc.) with harmonically distorted intermittent loads. The results show the appropriate performance of the proposed controllers during both steady-state and transient dynamic conditions.
Experimental Study of the Pore Structure and Permeability of Coal by Acidizing
Authors: Zhao Bo , Wen Guangcai , Sun Haitao , Zhao Xusheng
Published: May 2018

The permeability of coal reservoirs prominently determines methane flow in reservoirs. A large amount of coal reservoirs containing methane, however, have low permeability because pores in reservoirs are sealed. To solve this issue, we investigated the pore structure and permeability law of coal through contrastive analysis of the microstructure and macrostructure before and after acidizing, using ASAP 2020 and triaxial servo-controlled seepage equipment. An analysis of the experimental data revealed the mechanism and the key parameters of acidizing, such as acid mass fraction and acidizing time. In addition, we hold that the optimal mass fraction for the test specimens is about 12~15%. Furthermore, the acid reaction is divided into three stages according to characteristics of the reaction progress. An analysis of the reaction kinetics of “HCl-HF” states that the significant factors will impact the process of reaction, like the composition of coal, surface area of the acid-coal reaction, mass fraction of acids, and environment of the reaction system. The results provide a new idea and research method for further enhancing permeability and gas extraction.
Composition, Protein Profile and Rheological Properties of Pseudocereal-Based Protein-Rich Ingredients
Authors: Alonso-Miravalles Loreto , O’Mahony James A.
Published: May 2018

The objectives of this study were to investigate the nutrient composition, protein profile, morphology, and pasting properties of protein-rich pseudocereal ingredients (quinoa, amaranth, and buckwheat) and compare them to the more common rice and maize flours. Literature concerning protein-rich pseudocereal ingredients is very limited, mainly to protein profiling. The concentrations of macronutrients (i.e., ash, fat, and protein, as well as soluble, insoluble and total dietary fibre) were significantly higher for the protein-rich variants of pseudocereal-based flours than their regular protein content variants and the rice and maize flours. On profiling the protein component using sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE), all samples showed common bands at ~50 kDa and low molecular weight bands corresponding to the globulin fraction (~50 kDa) and albumin fraction (~10 kDa), respectively; except rice, in which the main protein was glutelin. The morphology of the starch granules was studied using scanning electron microscopy with quinoa and amaranth showing the smallest sized granules, while buckwheat, rice, and maize had the largest starch granules. The pasting properties of the ingredients were generally similar, except for buckwheat and amaranth, which showed the highest and lowest final viscosity, respectively. The results obtained in this study can be used to better understand the functionality and food applications of protein-rich pseudocereal ingredients.
Sedentary Behaviour in Swiss Children and Adolescents: Disentangling Associations with the Perceived and Objectively Measured Environment
Authors: Bringolf-Isler Bettina , De Hoogh Kees , Schindler Christian , Kayser Bengt , Suggs L. Suzanne , Dössegger Alain , Probst-Hensch Nicole ,   The SOPHYA Study Group
Published: May 2018

Identifying correlates of sedentary behaviour across all levels of the ecological model and understanding their interrelations is a promising method to plan effective interventions. The present study examined whether the objectively assessed and the perceived neighbourhood are associated with children’s sedentary behaviour time (SBT). A comprehensive set of factors at different levels of influence across the ecological model were taken into account and analysed for mediating and modifying effects. Analyses were based on 1306 children and adolescents (6–16 years) participating in the population-based SOPHYA-study. Accelerometers were used to assess SBT, the perceived environment was examined by a validated parental questionnaire, and objective environmental data were allocated using GIS (ArcMap 10.2, Esri, Redlands, CA, USA) for each family’s residential address. A high perceived safety was associated with less SBT. Boys, those whose residential neighbourhood was characterized by dead ends in urban areas, a low main street density in the neighbourhood of children and greenness were less likely to exhibit SBT. The association of the objective environment with the respective parental perceptions was low and no significant mediating effect was found for the perceived environment. We conclude for land-use planning to reduce sedentary behaviour objective environments should be complemented with efforts to increase parental sense of security.
Risk Factors and Spatial Clusters of Cryptosporidium Infection among School-Age Children in a Rural Region of Eastern China
Authors: Zheng Hao , He Jianfeng , Wang Li , Zhang Rong , Ding Zhen , Hu Wenbiao
Published: May 2018

The epidemiological features of Cryptosporidium infection among school-age children in China still remain unclear. Hereby, a cross-sectional study of 1637 children aged 3–9 years was designed to investigate the risk factors and spatial clusters of Cryptosporidium infection in a rural region of Eastern China. Stool specimens collected from participants were examined using the auramine-phenol and modified acid-fast staining. Univariable and multivariable analyses were performed to identify the risk factors of Cryptospordium infection. The spatial clusters were analyzed by a discrete Poisson model using SaTScan software. Our results showed that the overall prevalence of Cryptosporidium infection was 11‰ in the research region. At the age of 3–6 years (odds ratios (OR) = 3.072, 95% confidence intervals (CI): 1.001–9.427), not washing hands before eating and after defecation (OR = 3.003, 95% CI: 1.060–8.511) were recognized as risk factors. Furthermore, a high-risk spatial cluster (relative risk = 4.220, p = 0.025) was identified. These findings call for effective sustainable interventions including family and school-based hygienic education to reduce the prevalence of Cryptosporidium infection. Therefore, an early warning system based spatiotemporal models with risk factors is required to further improve the effectiveness and efficiency of cryptosporidiosis control in the future.
Optimal Route Searching with Multiple Dynamical Constraints—A Geometric Algebra Approach
Authors: Li Dongshuang , Yu Zhaoyuan , Luo Wen , Hu Yong , Che Xiaoyu , Yuan Linwang
Published: May 2018

The process of searching for a dynamic constrained optimal path has received increasing attention in traffic planning, evacuation, and personalized or collaborative traffic service. As most existing multiple constrained optimal path (MCOP) methods cannot search for a path given various types of constraints that dynamically change during the search, few approaches for dynamic multiple constrained optimal path (DMCOP) with type II dynamics are available for practical use. In this study, we develop a method to solve the DMCOP problem with type II dynamics based on the unification of various types of constraints under a geometric algebra (GA) framework. In our method, the network topology and three different types of constraints are represented by using algebraic base coding. With a parameterized optimization of the MCOP algorithm based on a greedy search strategy under the generation-refinement paradigm, this algorithm is found to accurately support the discovery of optimal paths as the constraints of numerical values, nodes, and route structure types are dynamically added to the network. The algorithm was tested with simulated cases of optimal tourism route searches in China’s road networks with various combinations of constraints. The case study indicates that our algorithm can not only solve the DMCOP with different types of constraints but also use constraints to speed up the route filtering.
Thermosensitive Injectable Hydrogel for Simultaneous Intraperitoneal Delivery of Doxorubicin and Prevention of Peritoneal Adhesion
Authors: Chen Chih-Hao , Kuo Chang-Yi , Chen Shih-Hsien , Mao Shih-Hsuan , Chang Chih-Yen , Shalumon K. T. , Chen Jyh-Ping
Published: May 2018

To improve intraperitoneal chemotherapy and to prevent postsurgical peritoneal adhesion, we aimed to develop a drug delivery strategy for controlled release of a chemotherapeutic drug from the intraperitoneally injected thermosensitive poly(N-isopropylacrylamide)-based hydrogel (HACPN), which is also endowed with peritoneal anti-adhesion properties. Anticancer drug doxorubicin (DOX) was loaded into the hydrogel (HACPN-DOX) to investigate the chemotherapeutic and adhesion barrier effects in vivo. A burst release followed by sustained release of DOX from HACPN-DOX was found due to gradual degradation of the hydrogel. Cell culture studies demonstrated the cytotoxicity of released DOX toward CT-26 mouse colon carcinoma cells in vitro. Using peritoneal carcinomatosis animal model in BALB/c mice with intraperitoneally injected CT-26 cells, animals treated with HACPN-DOX revealed the best antitumor efficacy judging from tumor weight and volume, survival rate, and bioluminescence signal intensity when compared with treatment with free DOX at the same drug dosage. HACPN (or HACPN-DOX) also significantly reduced the risk of postoperative peritoneal adhesion, which was generated by sidewall defect-cecum abrasion in tumor-bearing BALB/c mice, from gross and histology analyses. This study could create a paradigm to combine controlled drug release with barrier function in a single drug-loaded injectable hydrogel to enhance the intraperitoneal chemotherapeutic efficacy while simultaneously preventing postsurgical adhesion.
Developing an Ontology-Based Rollover Monitoring and Decision Support System for Engineering Vehicles
Authors: Xu Feixiang , Liu Xinhui , Zhou Chen
Published: May 2018

The increasing number of rollover accidents of engineering vehicles has attracted close attention; however, most researchers focus on the analysis and monitoring of rollover stability indexes and seldom the assessment and decision support for the rollover risk of engineering vehicles. In this context, an ontology-based rollover monitoring and decision support system for engineering vehicles is proposed. The ontology model is built for representing monitored rollover stability data with semantic properties and for constructing semantic relevance among the various concepts involved in the rollover domain. On the basis of this, ontology querying and reasoning methods based on the Simple Protocol and RDF Query Language (SPARQL) and Semantic Web Rule Language (SWRL) rules are utilized to realize the rollover risk assessment and to obtain suggested measures. PC and mobile applications (APPs) have also been developed to implement the above methods. In addition, five sets of rollover stability data for an articulated off-road engineering vehicle under different working conditions were analyzed to verify the accuracy and effectiveness of the proposed system.
The Human Takeover: A Call for a Venture into an Existential Opportunity
Authors: Lenartowicz Marta , Weinbaum David , Heylighen Francis , Kingsbury Kate , Harmsen Tjorven
Published: May 2018

We propose a venture into an existential opportunity for establishing a world ‘good enough’ for humans to live in. Defining an existential opportunity as the converse of an existential risk—that is, a development that promises to dramatically improve the future of humanity—we argue that one such opportunity is available and should be explored now. The opportunity resides in the moment of transition of the Internet—from mediating information to mediating distributed direct governance in the sense of self-organization. The Internet of tomorrow will mediate the execution of contracts, transactions, public interventions and all other change-establishing events more reliably and more synergistically than any other technology or institution. It will become a distributed, synthetically intelligent agent in itself. This transition must not be just observed, or exploited instrumentally: it must be ventured into and seized on behalf of entire humanity. We envision a configuration of three kinds of cognitive system—the human mind, social systems and the emerging synthetic intelligence—serving to augment the autonomy of the first from the ‘programming’ imposed by the second. Our proposition is grounded in a detailed analysis of the manner in which the socio-econo-political system has evolved into a powerful control mechanism that subsumes human minds, steers their will and automates their thinking. We see the venture into the existential opportunity described here as aiming at the global dissolution of the core reason of that programming’s effectiveness—the critical dependence of the continuity of human lives on the coherence of the socially constructed personas they ‘wear.’ Thus, we oppose the popular prediction of the upcoming, ‘dreadful AI takeover’ with a call for action: instead of worrying that Artificial Intelligence will soon come to dominate and govern the human world, let us think of how it could help the human being to finally be able to do it.
Interview with the 2018 JDB Travel Award Winner
Authors:   Journal of Developmental Biology (JDB) Editorial Office
Published: May 2018

The winner of the 2018 JDB Travel Award was granted to Ms. Victoria Deneke, BS, who is a fifth-year graduate student in Dr. Stefano Di Talia’s laboratory in the Department of Cell Biology at Duke University Medical Center, USA.[…]
Development of an Expression Vector to Overexpress or Downregulate Genes in Curvularia protuberata
Authors: Liu Chengke , Cleckler Blake , Morsy Mustafa
Published: May 2018

Curvularia protuberata, an endophytic fungus in the Ascomycota, provides plants with thermotolerance only when it carries a mycovirus known as Curvularia thermotolerance virus (CThTV), and forms a three-way symbiotic relationship among these organisms. Under heat stress, several genes are expressed differently between virus-free C. protuberata (VF) and C. protuberata carrying CThTV (AN). We developed an expression vector, pM2Z-fun, carrying a zeocin resistance gene driven by the ToxA promoter, to study gene functions in C. protuberata to better understand this three-way symbiosis. Using this new 3.7-kb vector, five genes that are differentially expressed in C. protuberata—including genes involved in the trehalose, melanin, and catalase biosynthesis pathways—were successfully overexpressed or downregulated in VF or AN C. protuberata strains, respectively. The VF overexpression lines showed higher metabolite and enzyme activity than in the control VF strain. Furthermore, downregulation of expression of the same genes in the AN strain resulted in lower metabolite and enzyme activity than in the control AN strain. The newly generated expression vector, pM2Z-fun, has been successfully used to express target genes in C. protuberata and will be useful in further functional expression studies in other Ascomycota fungi.
Saturated Imaging for Inspecting Transparent Aesthetic Defects in a Polymeric Polarizer with Black and White Stripes
Authors: Yu Cilong , Chen Peibing , Zhong Xiaopin , Pan Xizhou , Deng Yuanlong
Published: May 2018

Machine vision systems have been widely used in industrial production lines because of their automation and contactless inspection mode. In polymeric polarizers, extremely slight transparent aesthetic defects are difficult to detect and characterize through conventional illumination. To inspect such defects rapidly and accurately, a saturated imaging technique was proposed, which innovatively uses the characteristics of saturated light in imaging by adjusting the light intensity, exposure time, and camera gain. An optical model of defect was established to explain the theory by simulation. Based on the optimum experimental conditions, active two-step scanning was conducted to demonstrate the feasibility of this detection scheme, and the proposed method was found to be efficient for real-time and in situ inspection of defects in polymer films and products.
Theoretical Design of Multilayer Dental Posts Using CAD-Based Approach and Sol-Gel Chemistry
Authors: Maietta Saverio , De Santis Roberto , Catauro Michelina , Martorelli Massimo , Gloria Antonio
Published: May 2018

A computer-aided design (CAD)-based approach and sol-gel chemistry were used to design a multilayer dental post with a compositional gradient and a Young’s modulus varying from 12.4 to 2.3 GPa in the coronal-apical direction. Specifically, we propose a theoretical multilayer post design, consisting of titanium dioxide (TiO2) and TiO2/poly(ε-caprolactone) (PCL) hybrid materials containing PCL up to 24% by weight obtained using the sol-gel method. The current study aimed to analyze the effect of the designed multilayer dental post in endodontically treated anterior teeth. Stress distribution was investigated along and between the post and the surrounding structures. In comparison to a metal post, the most uniform distributions with lower stress values and no significant stress concentration were found when using the multilayer post.
Structural, Mechanical, Anisotropic, and Thermal Properties of AlAs in oC12 and hP6 Phases under Pressure
Authors: Zhang Wei , Chai Changchun , Song Yanxing , Fan Qingyang , Yang Yintang
Published: May 2018

The structural, mechanical, anisotropic, and thermal properties of oC12-AlAs and hP6-AlAs under pressure have been investigated by employing first-principles calculations based on density functional theory. The elastic constants, bulk modulus, shear modulus, Young’s modulus, B/G ratio, and Poisson’s ratio for oC12-AlAs and hP6-AlAs have been systematically investigated. The results show that oC12-AlAs and hP6-AlAs are mechanically stable within the considered pressure. Through the study of lattice constants (a, b, and c) with pressure, we find that the incompressibility of oC12-AlAs and hP6-AlAs is the largest along the c-axis. At 0 GPa, the bulk modulus B of oC12-AlAs, hP6-AlAs, and diamond-AlAs are 76 GPa, 75 GPa, and 74 Gpa, respectively, indicating that oC12-AlAs and hP6-AlAs have a better capability of resistance to volume than diamond-AlAs. The pressure of transition from brittleness to ductility for oC12-AlAs and hP6-AlAs are 1.21 GPa and 2.11 GPa, respectively. The anisotropy of Young’s modulus shows that oC12-AlAs and hP6-AlAs have greater isotropy than diamond-AlAs. To obtain the thermodynamic properties of oC12-AlAs and hP6-AlAs, the sound velocities, Debye temperature, and minimum thermal conductivity at considered pressure were investigated systematically. At ambient pressure, oC12-AlAs (463 K) and hP6-AlAs (471 K) have a higher Debye temperature than diamond-AlAs (433 K). At T = 300 K, hP6-AlAs (0.822 W/cm·K−1) has the best thermal conductivity of the three phases, and oC12-AlAs (0.809 W/cm·K−1) is much close to diamond-AlAs (0.813 W/cm·K−1).
On the Computational Methods for Solving the Differential-Algebraic Equations of Motion of Multibody Systems
Authors: Pappalardo Carmine Maria , Guida Domenico
Published: May 2018

In this investigation, different computational methods for the analytical development and the computer implementation of the differential-algebraic dynamic equations of rigid multibody systems are examined. The analytical formulations considered in this paper are the Reference Point Coordinate Formulation based on Euler Parameters (RPCF-EP) and the Natural Absolute Coordinate Formulation (NACF). Moreover, the solution approaches of interest for this study are the Augmented Formulation (AF) and the Udwadia–Kalaba Equations (UKE). As shown in this paper, the combination of all the methodologies analyzed in this work leads to general, effective, and efficient multibody algorithms that can be readily implemented in a general-purpose computer code for analyzing the time evolution of mechanical systems constrained by kinematic joints. This study demonstrates that multibody algorithm based on the combination of the NACF with the UKE turned out to be the most effective and efficient computational method. The conclusions drawn in this paper are based on the numerical results obtained for a benchmark multibody system analyzed by means of dynamical simulations.
The Influence of Ultrasonic Vibration Frequency on the Properties of TiN Coated Biomedical Ti–13Zr–13Nb
Authors: Shah A. , Izman S. , Ismail Siti Nurul Fasehah , Mas Ayu H. , Che Kob Che Ghani , Daud R. , Abdul Kadir Mohammed Rafiq
Published: May 2018

Bare biomedical grade titanium alloys are prone to degradation when in a body fluid environment. Surface coatings such as Physical Vapor Deposition (PVD) can serve as one of the options to minimize this issue. Past reports showed that the PVD coated layer consists of pores, pinholes, and columnar growths which act as channels through which the aggressive medium attacks the substrate. Duplex and multilayer coatings seem able to address this issue to varying extents but at the expense of manufacturing time and cost. In this paper, the effect of an ultrasonic vibration frequency on PVD TiN coated Ti–13Zr–13Nb biomedical alloy was studied. Disk type samples were prepared and coated with TiN at fixed conditions: bias voltage (−125 V), substrate temperature (300 °C), and nitrogen gas flow rate (300 standard cubic centimeters per minute (SCCM)). An ultrasonic vibration was then subsequently applied to the TiN coated samples at frequencies of 8 kHz and 16 kHz for 5 min. All TiN coated samples treated with ultrasonic vibrations exhibited a higher corrosion resistance than the untreated ones. Microstructure analysis under Field Emission Scanning Electron Microscopy (FESEM) confirmed that the coated sample at frequencies of 16 kHz produced the most compact coating. It is believed that the hammering effect of the ultrasonic vibration reduced the micro channels’ size in the coating and thus decelerated the corrosion’s attack.
Liquid-Metal Enabled Droplet Circuits
Authors: Ren Yi , Liu Jing
Published: May 2018

Conventional electrical circuits are generally rigid in their components and working styles, which are not flexible and stretchable. As an alternative, liquid-metal-based soft electronics offer important opportunities for innovation in modern bioelectronics and electrical engineering. However, their operation in wet environments such as aqueous solution, biological tissue or allied subjects still encounters many technical challenges. Here, we propose a new conceptual electrical circuit, termed as droplet circuit, to fulfill the special needs described above. Such unconventional circuits are immersed in a solution and composed of liquid metal droplets, conductive ions or wires, such as carbon nanotubes. With specifically-designed topological or directional structures/patterns, the liquid-metal droplets composing the circuit can be discrete and disconnected from each other, while achieving the function of electron transport through conductive routes or the quantum tunneling effect. The conductive wires serve as electron transfer stations when the distance between two separate liquid-metal droplets is far beyond that which quantum tunneling effects can support. The unique advantage of the current droplet circuit lies in the fact that it allows parallel electron transport, high flexibility, self-healing, regulation and multi-point connectivity without needing to worry about the circuit break. This would extend the category of classical electrical circuits into newly emerging areas like realizing room temperature quantum computing, making brain-like intelligence or nerve–machine interface electronics, etc. The mechanisms and potential scientific issues of the droplet circuits are interpreted and future prospects in this direction are outlined.
Adsorption of N2, NO2 and CO2 on Epistilbite Natural Zeolite from Jalisco, Mexico after Acid Treatment
Authors: Hernández-Espinosa Miguel Angel , Quiroz-Estrada Karla , Petranovskii Vitalii , Rojas Fernando , Portillo Roberto , Salgado Martha Alicia , Marcelo Miguel , Rubio Efraín , Felipe Carlos
Published: May 2018

Emissions of carbon dioxide (CO2) and nitrogen dioxide (NO2) in recent years has been increased considerably. One way to reduce the concentration of these greenhouse gases in the atmosphere is adsorptive capture. This paper describes the main results of adsorption of N2, NO2, and CO2 on epistilbite, both natural and on samples that were chemically treated at various concentrations of HCl. Data on the adsorption of CO2 and NO2 were evaluated by the Freundlich and Langmuir equations. Additionally, the thermodynamic parameters of adsorption were calculated, including the degree of interaction of the zeolite samples with gases by gradually changing the isosteric heat capacities of adsorption. The acid treatment improves the adsorption capacity of epistilbite with respect to NO2 and CO2, due the replacement of large extra-framework cation by small H+ ions. The improvement in the distribution of pore sizes in epistilbite samples was calculated by the method of Barrett-Joyner-Halenda. The sample H1 that was prepared in a moderately concentrated acid showed the best behavior in the CO2 adsorption processes, while the natural EPIN material preferably adsorbs NO2.
Cold Priming Induced Tolerance to Subsequent Low Temperature Stress is Enhanced by Melatonin Application during Recovery in Wheat
Authors: Sun Luying , Li Xiangnan , Wang Zongshuai , Sun Zhongwei , Zhu Xiancan , Liu Shengqun , Song Fengbin , Liu Fulai , Wang Yongjun
Published: May 2018

Cold priming can alleviate the effects of subsequent cold stress on wheat plant growth. Melatonin plays a key role in cold stress response in plants. In this study, the effects of foliar melatonin application during recovery on the cold tolerance of cold primed wheat plants were investigated. It was found that both melatonin and cold priming increased the photosynthetic rate and stomatal conductance, enhanced the activities of antioxidant enzymes, and altered the related gene expressions in wheat under cold stress. Melatonin application is helpful for the photosynthetic carbon assimilation and membrane stability of the cold primed plants under cold stress. These results suggested that foliar melatonin application during recovery enhanced the cold priming induced tolerance to subsequent low temperature stress in wheat.
A Preliminary Study of Aroma Composition and Impact Odorants of Cabernet Franc Wines under Different Terrain Conditions of the Loess Plateau Region (China)
Authors: Jiang Bao , Zhang Zhen-Wen
Published: May 2018

Due to its appropriate climate characteristics, the Loess Plateau region is considered to be one of the biggest optimal regions for producing high-quality mountain wine in China. However, the complex landform conditions of vineyards are conducive to the formation of mountainous microclimates, which ultimately influence the wine quality. This study aimed to elucidate the influences of three terrain conditions of the Loess Plateau region on the aroma compounds of Cabernet Franc wines by using solid phase microextraction (SPME) with gas chromatography-mass spectrometry (GC-MS). A total of 40, 36 and 35 volatiles were identified and quantified from the flat, lower slope and higher slope vineyards, respectively. Esters were the largest group of volatiles, accounting for 54.6–56.6% of total volatiles, followed by alcohols. Wines from the slope lands had the higher levels of aroma compounds than that from flat land. According to their aroma-active values (OAVs), ethyl hexanoate, ethyl octanoate and isoamyl acetate were the most powerful compounds among the eight impact odorants, showing only quantitative but not qualitative differences between the three terrain wines. The shapes of the OAVs for three terrain wines were very similar.
Ursolic Acid Attenuates Atherosclerosis in ApoE−/− Mice: Role of LOX-1 Mediated by ROS/NF-κB Pathway
Authors: Li Qiu , Zhao Wenwen , Zeng Xi , Hao Zhihui
Published: May 2018

Atherosclerosis, a chronic inflammatory disease, is a major contributor to cardiovascular diseases. Ursolic acid (UA) is a phytonutrient with widely biological effects including anti-oxidative, anti-inflammatory, and so on. At present, the effect of UA on atherosclerosis and the mechanism of action are still obscure. This study focused on investigating the effects of UA on atherosclerosis both in vivo and in vitro. We first selected LOX-1 as our target, which was reckoned as a new promising receptor for treating atherosclerosis. The evaluation in vitro suggested that UA significantly decreased endothelial LOX-1 expression induced by LPS both in mRNA and protein levels. Pre-treatment of UA also inhibited TLR4/MyD88 signaling activated by LPS. Moreover, UA reduced ROS production and suppressed the activation of NF-κB stimulated by LPS. Particularly, the evaluation in vivo further verified the conclusion obtained in vitro. In ApoE−/− mice fed with an atherogenic diet, both UA (100 mg/kg/day) and simvastatin significantly attenuated atherosclerotic plaque formation and shrunk necrotic core areas. The enhanced expression of LOX-1 in atherosclerotic aorta was also dramatically decreased by administration of UA. Taken together, these results suggested that UA, with anti-atherosclerotic activity through inhibition of LOX-1 mediated by ROS/NF-κB signaling pathways, may become a valuable vascular protective candidate for the treatment of atherosclerosis.
Comparative Study of the ORR Activity and Stability of Pt and PtM (M = Ni, Co, Cr, Pd) Supported on Polyaniline/Carbon Nanotubes in a PEM Fuel Cell
Authors: Kaewsai Duanghathai , Hunsom Mali
Published: May 2018

The oxygen reduction reaction (ORR) activity and stability of platinum (Pt) and PtM (M = Ni, Co, Cr, Pd) supported on polyaniline/carbon nanotube (PtM/PANI-CNT) were explored and compared with the commercial Pt/C catalyst (ETEK). The Pt/PANI-CNT catalyst exhibited higher ORR activity and stability than the commercial Pt/C catalyst even though it had larger crystallite/particle sizes, lower catalyst dispersion and lower electrochemical surface area (ESA), probably because of its high electrical conductivity. The addition of second metal (M) enhanced the ORR activity and stability of the Pt/PANI-CNT catalyst, because the added M induced the formation of a PtM alloy and shifted the d-band center to downfield, leading to a weak chemical interaction between oxygenated species and the catalyst surface and, therefore, affected positively the catalytic activity. Among all the tested M, the addition of Cr was optimal. Although it improved the ORR activity of the Pt/PANI-CNT catalyst slightly less than that of Pd (around 4.98%) in low temperature (60 °C)/pressure (1 atm abs), it reduced the ESA loss by around 14.8% after 1000 cycles of repetitive cyclic voltammetry (CV). In addition, it is cheaper than Pd metal. Thus, Cr was recommended as the second metal to alloy with Pt on the PANI-CNT support.
Novel Sulfur/Ethylenediamine-Functionalized Reduced Graphene Oxide Composite as Cathode Material for High-performance Lithium-Sulfur Batteries
Authors: Chen Zhuo , Sun Zhenghao , Zhang Yongguang , Tan Taizhe , Tian Yuan , Chen Zhihong
Published: May 2018

Sulfur/ethylenediamine-functionalized reduced graphene oxide (S/EDA-RGO) nanocomposites were synthesized using a simple process. Ethylenediamine (EDA) was employed as both the reducing agent and the modification component. The morphologies, microstructures, and compositions of S/EDA-RGO composites were characterized by various detection techniques. The data indicated that EDA-RGO used as scaffolds for sulfur cathodes could enhance the electronic conductivity of the composites and strengthen the adsorbability of polysulfides. Meanwhile, the electrochemical properties of both S/EDA-RGO and S/RGO composites that were used as cathodes for lithium-sulfur (Li-S) batteries were investigated. The initial discharge capacity of S/EDA-RGO composites reached 1240 mAh g−1, with reversible capacity being maintained at 714 mAh g−1 after 100 cycles. The improvement in cycling stability of S/EDA-RGO composites was further verified at different current rates. These findings demonstrated that proper surface modification of RGO by EDA reducing agent might improve the electrochemical performances of Li–S batteries.
The Role of Lipids in Human Milk and Infant Formulae
Authors: Mazzocchi Alessandra , D’Oria Veronica , Cosmi Valentina De , Bettocchi Silvia , Milani Gregorio Paolo , Silano Marco , Agostoni Carlo
Published: May 2018

The quantity and quality of dietary lipids in infant formulae have a significant impact on health outcomes, especially when fat storing and/or absorption are limited (e.g., preterm birth and short bowel disease) or when fat byproducts may help to prevent some pathologies (e.g., atopy). The lipid composition of infant formulae varies according to the different fat sources used, and the potential biological effects are related to the variety of saturated and unsaturated fatty acids. For example, since lipids are the main source of energy when the normal absorptive capacity of the digestive tract is compromised, medium-chain saturated fatty acids might cover this requirement. Instead, ruminant-derived trans fatty acids and metabolites of n-3 long-chain polyunsaturated fatty acids with their anti-inflammatory properties can modulate immune function. Furthermore, dietary fats may influence the nutrient profile of formulae, improving the acceptance of these products and the compliance with dietary schedules.
Iron Release from Soybean Seed Ferritin Induced by Cinnamic Acid Derivatives
Authors: Sha Xuejiao , Chen Hai , Zhang Jingsheng , Zhao Guanghua
Published: May 2018

Plant ferritin represents a novel class of iron supplement, which widely co-exists with phenolic acids in a plant diet. However, there are few reports on the effect of these phenolic acids on function of ferritin. In this study, we demonstrated that cinnamic acid derivatives, as widely occurring phenolic acids, can induce iron release from holo soybean seed ferritin (SSF) in a structure-dependent manner. The ability of the iron release from SSF by five cinnamic acids follows the sequence of Cinnamic acid > Chlorogenic acid > Ferulic acid > p-Coumaric acid > Trans-Cinnamic acid. Fluorescence titration in conjunction with dialysis results showed that all of these five compounds have a similar, weak ability to bind with protein, suggesting that their protein-binding ability is not related to their iron release activity. In contrast, both Fe2+-chelating activity and reducibility of these cinnamic acid derivatives are in good agreement with their ability to induce iron release from ferritin. These studies indicate that cinnamic acid and its derivatives could have a negative effect on iron stability of holo soybean seed ferritin in diet, and the Fe2+-chelating activity and reducibility of cinnamic acid and its derivatives have strong relations to the iron release of soybean seed ferritin.