bluuebunny/crossref_metadata_2025 huggingface dataset:
Thermomechanical Behavior of Textile Reinforced Cementitious Composites Subjected to Fire
Authors: Kapsalis Panagiotis , El Kadi Michael , Vervloet Jolien , De Munck Matthias , Wastiels Jan , Triantafillou Thanasis , Tysmans Tine
Published: February 2019

The mechanical behavior of textile reinforced cementitious composites (TRC) has been a topic of wide investigation during the past 30 years. However, most of the investigation is focused on the behavior under ambient temperatures, while only a few studies about the behavior under high temperatures have been conducted thus far. This paper focused on the thermomechanical behavior of TRC after exposure to fire and the residual capacity was examined. The parameters that were considered were the fiber material, the thickness of the concrete cover, the moisture content and the temperature of exposure. The specimens were exposed to fire only from one side and the residual strength was measured by means of flexural capacity. The results showed that the critical factor that affects the residual strength was the coating of the textiles and the law of the coating mass loss with respect to temperature. The effect of the other parameters was not quantified. The degradation of the compressive strength of TRC was quantified with respect to temperature. It was also concluded that a highly asymmetrical design scheme might lead to premature failure.
Deep Reinforcement Learning for Query-Conditioned Video Summarization
Authors: Zhang Yujia , Kampffmeyer Michael , Zhao Xiaoguang , Tan Min
Published: February 2019

Query-conditioned video summarization requires to (1) find a diverse set of video shots/frames that are representative for the whole video, and that (2) the selected shots/frames are related to a given query. Thus it can be tailored to different user interests leading to a better personalized summary and differs from the generic video summarization which only focuses on video content. Our work targets this query-conditioned video summarization task, by first proposing a Mapping Network (MapNet) in order to express how related a shot is to a given query. MapNet helps establish the relation between the two different modalities (videos and query), which allows mapping of visual information to query space. After that, a deep reinforcement learning-based summarization network (SummNet) is developed to provide personalized summaries by integrating relatedness, representativeness and diversity rewards. These rewards jointly guide the agent to select the most representative and diversity video shots that are most related to the user query. Experimental results on a query-conditioned video summarization benchmark demonstrate the effectiveness of our proposed method, indicating the usefulness of the proposed mapping mechanism as well as the reinforcement learning approach.
The Use of Chalcedonite as a Biosorption Bed in the Treatment of Groundwater
Authors: Papciak Dorota , Domoń Andżelika , Puszkarewicz Alicja , Kaleta Jadwiga
Published: February 2019

The conducted laboratory tests allowed determination of the efficiency of removing ammonium nitrogen, iron, and manganese in the biofiltration process on chalcedonite beds. The process of water purification was carried out by a single- and two-stage biofiltration method with gravitational and anti-gravitational flow. The study examined the extent to which chemical activation of the bed with potassium manganese (VII) affects the course of the nitrification process and the rate of biofilm formation. The obtained test results indicate that two-stage biofiltration, with initial chemical activation at the first stage of biofiltration, is an effective method for purifying waters with an abnormal content of ammonium nitrogen with simultaneous removal of iron and manganese. Activation of the bed had an effect on, among other things: biofilm formation time, efficiency of removing manganese (II) ions, and oxygen consumption in the biofiltration process. Due to the longer maturation time of the activated bed, the normative value of ammonium nitrogen (< 0.39 N-NH4+) was obtained on the 23rd day of the operation of the filters, and in the non-activated bed on the 14th day. The method of bed preparation did not affect the efficiency of removal of iron compounds.
Joint Pedestrian and Body Part Detection via Semantic Relationship Learning
Authors: Gu Junhua , Lan Chuanxin , Chen Wenbai , Han Hu
Published: February 2019

While remarkable progress has been made to pedestrian detection in recent years, robust pedestrian detection in the wild e.g., under surveillance scenarios with occlusions, remains a challenging problem. In this paper, we present a novel approach for joint pedestrian and body part detection via semantic relationship learning under unconstrained scenarios. Specifically, we propose a Body Part Indexed Feature (BPIF) representation to encode the semantic relationship between individual body parts (i.e., head, head-shoulder, upper body, and whole body) and highlight per body part features, providing robustness against partial occlusions to the whole body. We also propose an Adaptive Joint Non-Maximum Suppression (AJ-NMS) to replace the original NMS algorithm widely used in object detection, leading to higher precision and recall for detecting overlapped pedestrians. Experimental results on the public-domain CUHK-SYSU Person Search Dataset show that the proposed approach outperforms the state-of-the-art methods for joint pedestrian and body part detection in the wild.
Influence of Frost Growth and Migration in Cryogenic Heat Exchanger on Air Refrigerator
Authors: Yang Shanju , Liu Zhan , Fu Bao , Chen Yu
Published: February 2019

Frost formation degrades the performance of heat exchangers greatly, thus influencing the cryogenic refrigerator. Different from frost formation on the evaporator surface, the growth and migration of frost layer inside the heat exchanger is of low temperature and humidity. In addition to the constantly changing boundary conditions, the effective prediction is difficult. In the present study, a numerical model was proposed to analyze the frost formation in the cryogenic heat exchanger of a reverse Brayton air refrigerator. Under small amounts of moisture, the growing of frost layer was simulated through the numerical heat and mass transfer by adopting semiempirical correlations. The frost formation model was inserted into the transient model of refrigerator, and numerical calculations were performed on heat and mass transfer rates, and growth and migration of frost layers in forced convection conditions. Experiments were conducted under different air humidity to investigate the frost formation and verify the numerical model. Through the model, the influences of frosting on the refrigerator were evaluated under different moisture contents and running time. It can be used to predict the performance of air refrigerators with low humidity and provide a basis for improving the system operation and efficiency.
Efficient Transcoding and Encryption for Live 360 CCTV System
Authors: Thanh Le Tuan , Jeong JongBeom , Ryu Eun-Seok
Published: February 2019

In recent years, the rapid development of surveillance information in closed-circuit television (CCTV) has become an indispensable element in security systems. Several CCTV systems designed for video compression and encryption need to improve for the best performance and different security levels. Specially, the advent of 360 video makes the CCTV promising for surveillance without any blind areas. Compared to current systems, 360 CCTV requires the large bandwidth with low latency to run smoothly. Therefore, to improve the system performance, it needs to be more robust to run smoothly. Video transmission and transcoding is an essential process in converting codecs, changing bitrates or resizing the resolution for 360 videos. High-performance transcoding is one of the key factors of real time CCTV stream. Additionally, the security of video streams from cameras to endpoints is also an important priority in CCTV research. In this paper, a real-time transcoding system designed with the ARIA block cipher encryption algorithm is presented. Experimental results show that the proposed method achieved approximately 200% speedup compared to libx265 FFmpeg in transcoding task, and it could handle multiple transcoding sessions simultaneously at high performance for both live 360 CCTV system and existing 2D/3D CCTV system.
Experimental Research into the Evolution of Permeability in a Broken Coal Mass under Cyclic Loading and Unloading Conditions
Authors: Li Bo , Zou Quanle , Liang Yunpei
Published: February 2019

The permeability characteristics of a broken coal mass under repeated loading and unloading conditions exert significance on spontaneous combustion of coal in goaf during the mining of coal seam groups. Considering this, by using the seepage test system for broken coal-rock mass, seepage tests under cyclic loading and unloading conditions, were carried out on broken coal masses. The test results show that the fitting curves between permeability and effective stress, strain and porosity are a logarithmic function, cubic function and power function, respectively. Besides, the permeability of a broken coal sample under cyclic loading and unloading conditions is determined by its porosity, which conforms to the cubic law. With increased cyclic loading and unloading times, the permeability loss, stress sensitivity and the crushing amount of the broken coal sample were gradually reduced, but the particle size gradation of the broken coal sample gradually became better. During one loading and unloading cycle, the stress sensitivity of the permeability of coal samples in the loading stage was far higher than that in the unloading stage. In the loading stage, the re-arrangement, breakage and compressive deformation of coal particles can lead to a reduction in porosity, consequently resulting in a decreased permeability. In the unloading stage, only the permeability reduction of coal samples due to particle deformation can be recovered.
Effect of Borosilicate Glass on Thermal Neutron Shielding Performance and Compressive Strength of Cement Mortar
Authors: Lee Jun-Cheol , Choi Hyeong-Gil
Published: February 2019

The effect of borosilicate glass on the thermal neutron shielding performance and the compressive strength of cement mortar was investigated. The borosilicate glass was used as a replacement material for fine aggregate in this study. The cement mortars were mixed by four different replacement ratios of borosilicate glass. The following tests were conducted with the cement mortar: (1) Compressive strength, (2) TG/DSC and (3) neutron shielding rate using 241Am–Be neutron source. Results indicated that the cement mortar with borosilicate glass showed higher compressive strength and higher thermal neutron shielding rate as the replacement ratio of borosilicate glass increased. The increase of the compressive strength and the thermal neutron shielding rate was associated with the pozzolanic reaction of borosilicate glass and the increase of boron content in cement mortar, respectively.
Effect of Nylon Fiber Addition on the Performance of Recycled Aggregate Concrete
Authors: Lee Seungtae
Published: February 2019

The adhered mortars in recycled aggregates (RA) may lower the performance of the concrete, by for instance reducing its strength and durability, and by cracking. In the present study, the effect of nylon fiber (NF) on the permeability as well as on the mechanical properties of concrete incorporating 100% RA was experimentally investigated. Concrete was produced by adding 0, 0.6 and 1.2 kg/m3 of NF and then cured in water for a predetermined period. Measurements of compressive and split tensile strengths, ultrasonic pulse velocity and total charge passed through concrete were carried out, and the corresponding test results were compared to those of concrete incorporating crushed stone aggregate (CA). In addition, the microstructures of 28-day concretes were examined by using the FE-SEM technique. The test results indicated that recycled coarse aggregate concrete (RAC) showed a lower performance than crushed stone aggregate concrete (CAC) because of the adhered mortars in RA. However, it was obvious that the addition of NF in RAC mixes was much more effective in enhancing the performance of the concretes due to the crack bridging effect from NF. In particular, a high content of NF (1.2 kg/m3) led to a beneficial effect on concrete properties compared to a low content of NF (0.6 kg/m3) with respect to mechanical properties and permeability, especially for RAC mixes.
A Comprehensive Survey of Accurate and Efficient Aggregation Modeling for High Penetration of Large-Scale Wind Farms in Smart Grid
Authors: Liu Fang , Ma Junjie , Zhang Wendan , Wu Min
Published: February 2019

As one of the important renewable energies, wind power has been exploited worldwide. Modeling plays an important role in the high penetration of wind farms in smart grids. Aggregation modeling, whose benefits include low computational complexity and high computing speed, is widely used in wind farm modeling and simulation. To contribute to the development of wind power generation, a comprehensive survey of the aggregation modeling of wind farms is given in this article. A wind farm aggregation model consists of three parts, respectively, the wind speed model, the wind turbine generator (WTG) model, and the WTG transmission system model. Different modeling and aggregation methods, principles, and formulas for the above three parts are introduced. First, the features and emphasis of different wind speed models are discussed. Then, the aggregated wind turbine generator (WTG) models are divided into single WTG and multi-WTG aggregation models, considering the aggregation of wind turbines and generators, respectively. The calculation methods for the wind conditions and parameters of different aggregation models are discussed. Finally, the WTG transmission model of the wind farm from the aggregation bus is introduced. Some research directions are highlighted in the end according to the issues related to the aggregation modeling of wind farms in smart grids.
Seismic Performance of Curved Bridges with Longitudinal Slope
Authors: Su Peng , Chen Yanjiang , Zhao Zhongwei , Yan Weiming
Published: February 2019

A curved bridge test model with a scale ratio of 1:10 was constructed to investigate the influence of site conditions on curved bridges with longitudinal slopes based on a similar theory. The natural ground motions of five different groups, namely, Sites A–E, were selected from the Pacific Earthquake Engineering Center (PEER) seismic database, and the shaking table model test was conducted under horizontal unidirectional and bidirectional excitations. Results showed that the structural response of the curved bridge is sensitive to the ground motion of different site conditions. Spatial characteristics are observed in the main girder structural response of the curved bridge. When the curved bridge is parallel to the direction of the principal ground motion, the rotation effect of the main girder is greater than that perpendicular to the direction of the principal ground motion. The rotation effect of the main girder leads to evident beam end and bearing displacements at the low pier. The seismic excitation direction and pier height notably affect the displacement response of the pier, and the tangential displacement response of the fixed pier is sensitive to seismic excitation.
Research Progress on Flexible Oxide-Based Thin Film Transistors
Authors: Zhang Lirong , Xiao Wenping , Wu Weijing , Liu Baiquan
Published: February 2019

Oxide semiconductors have drawn much attention in recent years due to their outstanding electrical performance, such as relatively high carrier mobility, good uniformity, low process temperature, optical transparency, low cost and especially flexibility. Flexible oxide-based thin film transistors (TFTs) are one of the hottest research topics for next-generation displays, radiofrequency identification (RFID) tags, sensors, and integrated circuits in the wearable field. The carrier transport mechanism of oxide semiconductor materials and typical device configurations of TFTs are firstly described in this invited review. Then, we describe the research progress on flexible oxide-based TFTs, including representative TFTs fabricated on different kinds of flexible substrates, the mechanical stress effect on TFTs and optimized methods to reduce this effect. Finally, an outlook for the future development of oxide-based TFTs is given.
A Grid-Based Swarm Intelligence Algorithm for Privacy-Preserving Data Mining
Authors: Wu Tsu-Yang , Lin Jerry Chun-Wei , Zhang Yuyu , Chen Chun-Hao
Published: February 2019

Privacy-preserving data mining (PPDM) has become an interesting and emerging topic in recent years because it helps hide confidential information, while allowing useful knowledge to be discovered at the same time. Data sanitization is a common way to perturb a database, and thus sensitive or confidential information can be hidden. PPDM is not a trivial task and can be concerned an Non-deterministic Polynomial-time (NP)-hard problem. Many algorithms have been studied to derive optimal solutions using the evolutionary process, although most are based on straightforward or single-objective methods used to discover the candidate transactions/items for sanitization. In this paper, we present a multi-objective algorithm using a grid-based method (called GMPSO) to find optimal solutions as candidates for sanitization. The designed GMPSO uses two strategies for updating gbest and pbest during the evolutionary process. Moreover, the pre-large concept is adapted herein to speed up the evolutionary process, and thus multiple database scans during each evolutionary process can be reduced. From the designed GMPSO, multiple Pareto solutions rather than single-objective algorithms can be derived based on Pareto dominance. In addition, the side effects of the sanitization process can be significantly reduced. Experiments have shown that the designed GMPSO achieves better side effects than the previous single-objective algorithm and the NSGA-II-based approach, and the pre-large concept can also help with speeding up the computational cost compared to the NSGA-II-based algorithm.
Assessment of the Potential of High-Performance Buildings to Achieve Zero Energy: A Case Study
Authors: Wang Dan , Pang Xiufeng , Wang Wei , Qi Zewei , Li Jin , Luo Duo
Published: February 2019

Buildings that are designed with aggressive energy performance targets are defined broadly in this study as high-performance buildings. As the technology advances, some of these buildings have the potential to become zero-energy ready through the adoption of cost-effective measures, such as retro-commissioning and occupant behavior techniques. This study demonstrated the viability of an office building to achieve the zero-energy goal and intended to engage the owners of similar facilities. The case building was designed as a very low-energy building with an energy use intensity (EUI) goal of 42 kWh/(m2 a), and the actual EUI was 23.9 kWh/(m2 a). The calibrated simulation approach was employed in the study, and the results indicated that the case building can achieve the zero-energy goal by optimizing the controls of the HVAC (Heating, Ventilation and Air Conditioning) system, changing the occupant behavior and improving the performance of the photovoltaic system.
Control of Flow around an Oscillating Plate for Lift Enhancement by Plasma Actuators
Authors: Sato Saya , Yokoyama Hiroshi , Iida Akiyoshi
Published: February 2019

During insect flight, a feathering motion of the wing’s controls vortex shedding for lift enhancement. In this study, in order to control the flow around a wing flapping with simplified sinusoidal motion, plasma actuators were introduced to simplify the complex feathering motion. In a wind tunnel, a smoke-wire method was enacted to visualize the flow fields around an oscillating plate with an attack angle of 4° in a uniform flow for the baseline and controlled cases. The actuator placed around the leading edge was found to suppress the flow separation on the top surface. Numerical simulations were performed to investigate the control effects on the fluctuating lift, where the control effects by the intermittently driven actuator were also predicted. The actuator installed on the top surface throughout the up-stroke motion was found to suppress vortex shedding from the trailing edge, which resulted in an 11% lift enhancement compared to the baseline case. In regard to the effects of the installation position, it was found that the actuator placed on the top surface was effective, compared to the cases for installation on the bottom surface or both surfaces.
Design and Characterization of Electrically Conductive Structures Additively Manufactured by Material Extrusion
Authors: Watschke Hagen , Hilbig Karl , Vietor Thomas
Published: February 2019

Multi-material additive manufacturing offers new design freedom for functional integration and opens new possibilities in innovative part design, for instance, a local integration of electrically conductive structures or heat radiant surfaces. Detailed experimental investigations on materials with three different fillers (carbon black (CB), carbon nanotubes (CNT) and nano copper wires) were conducted to identify process-specific influencing factors on electrical conductivity and resistive heating. In this regard, raster angle orientation, extrusion temperature, speed and flow rate were investigated. A variation of the raster angle (0°, ±45°, and 90°) shows the highest influence on resistivity. An angle of 0° had the lowest electrical resistance and the highest temperature increase due to resistive heating. The material filled with nano copper wires showed the highest electrical conductivity followed by the CNT filled material and materials filled with CB. Both current–voltage characteristics and voltage-dependent heat distribution of the surface temperature were determined by using a thermographic camera. The highest temperature increase was achieved by the CNT filled material. The materials filled with CB and nano copper wires showed increased electrical resistance depending on temperature. Based on the experiments, solution principles and design rules for additively manufactured electrically conductive structures are derived.
S-Box Based Image Encryption Application Using a Chaotic System without Equilibrium
Authors: Wang Xiong , Çavuşoğlu Ünal , Kacar Sezgin , Akgul Akif , Pham Viet-Thanh , Jafari Sajad , Alsaadi Fawaz E. , Nguyen Xuan Quynh
Published: February 2019

Chaotic systems without equilibrium are of interest because they are the systems with hidden attractors. A nonequilibrium system with chaos is introduced in this work. Chaotic behavior of the system is verified by phase portraits, Lyapunov exponents, and entropy. We have implemented a real electronic circuit of the system and reported experimental results. By using this new chaotic system, we have constructed S-boxes which are applied to propose a novel image encryption algorithm. In the designed encryption algorithm, three S-boxes with strong cryptographic properties are used for the sub-byte operation. Particularly, the S-box for the sub-byte process is selected randomly. In addition, performance analyses of S-boxes and security analyses of the encryption processes have been presented.
An Efficient Encoding Algorithm Using Local Path on Huffman Encoding Algorithm for Compression
Authors: Erdal Erdal , Ergüzen Atilla
Published: February 2019

Huffman encoding and arithmetic coding algorithms have shown great potential in the field of image compression. These algorithms are the origin of current image compression techniques. Nevertheless, there are some deficiencies in both algorithms that use the frequencies of the characters in the data. They aim to represent the symbols used in the data in the shortest bit sequence. However, they represent data that has a low frequency of use with very long bit sequences. The arithmetic coding algorithm was developed to address the shortcomings of the Huffman encoding algorithm. This paper proposes an efficient, alternative encoding algorithm that uses the Huffman encoding algorithm. The main objective of the proposed algorithm is to reduce the number of bits that are symbolized with long bit codewords by the Huffman encoding algorithm. Initially, the Huffman encoding algorithm is applied to the data. The characters that are represented by the short bit sequence from the Huffman encoding algorithm are ignored. Flag bits are then added according to whether the successive symbols are on the same leaf. If the next character is not on the same leaf, flag bit “0” is added, otherwise flag bit “1” is added between the characters. In other words, the key significance of this algorithm is that it uses the effective aspects of the Huffman encoding algorithm, and it also proposes a solution to long bit sequences that cannot be efficiently represented. Most importantly, the validity of the algorithm is meticulously evaluated with three different groups of images. Randomly selected images from the USC-SIPI and STARE databases, and randomly selected standard images on internet, are used. The algorithm encodes compressing operations for images successfully. Some images that have a balanced tree structure have yielded close results compared to other algorithms. However, when the total results are inspected, the proposed encoding algorithm achieved excellent results.
Hidden Charge Orders in Low-Dimensional Mott Insulators
Authors: Fazzini Serena , Montorsi Arianna
Published: February 2019

The opening of a charge gap driven by interaction is a fingerprint of the transition to a Mott insulating phase. In strongly correlated low-dimensional quantum systems, it can be associated to the ordering of hidden non-local operators. For Fermionic 1D models, in the presence of spin–charge separation and short-ranged interaction, a bosonization analysis proves that such operators are the parity and/or string charge operators. In fact, a finite fractional non-local parity charge order is also capable of characterizing some two-dimensional Mott insulators, in both the Fermionic and the bosonic cases. When string charge order takes place in 1D, degenerate edge modes with fractional charge appear, peculiar of a topological insulator. In this article, we review the above framework, and we test it to investigate through density-matrix-renormalization-group (DMRG) numerical analysis the robustness of both hidden orders at half-filling in the 1D Fermionic Hubbard model extended with long range density-density interaction. The preliminary results obtained at finite size including several neighbors in the case of dipolar, screened and unscreened repulsive Coulomb interactions, confirm the phase diagram of the standard extended Hubbard model. Besides the trivial Mott phase, the bond ordered and charge density wave insulating phases are also not destroyed by longer ranged interaction, and still manifest hidden non-local orders.
Doppler Shift Time Expansion Resolution and Spectral Performance in Wideband Real-Time RF Channel Emulators
Authors: Rossi Massimiliano
Published: February 2019

The possibility to test a radio frequency transceiver through the use of appropriate channel emulators allows evaluating their performance under various operating conditions. Many systems are able to operate with a relatively limited instantaneous bandwidth by applying known statistical models. Sometimes, it is necessary to evaluate the performance of a RF transceiver installed on high or very high speed platforms over predictable trajectories using optionally DEM (Digital Elevation Model) data of the terrain to estimate the number of stimulated paths and their contributions during the flight. When the instantaneous bandwidth of the signal becomes high (over several hundreds of MHz), one of the most important phenomena to consider is the Doppler spread induced by the channel and traditional narrowband models become useless. This paper presents some results when a time expansion is adopted to emulate the transceiver dynamic and the consequent Doppler spread with the aim of controlling the spectral purity of the emulated propagation channel.
Characterization of Human Health Risks from Particulate Air Pollution in Selected European Cities
Authors: Chalvatzaki Eleftheria , Chatoutsidou Sofia Eirini , Lehtomäki Heli , Almeida Susana Marta , Eleftheriadis Konstantinos , Hänninen Otto , Lazaridis Mihalis
Published: February 2019

The objective of the current study was to estimate health risk indexes caused by the inhalation of particulate matter (PM) by adult males and children using data sampled in three European cities (Athens, Kuopio, Lisbon). Accordingly, the cancer risk (CR) and the hazard quotient (HQ) were estimated from particle-bound metal concentrations whilst the epidemiology-based excess risk (ER), the attributable fraction (AF), and the mortality cases were obtained due to exposure to PM10 and PM2.5. CR and HQ were estimated using two methodologies: the first methodology incorporated the particle-bound metal concentrations (As, Cd, Co, Cr, Mn, Ni, Pb) whereas the second methodology used the deposited dose rate of particle-bound metals in the respiratory tract. The indoor concentration accounts for 70% infiltration from outdoor air for the time activity periods allocated to indoor environments. HQ was lower than 1 and the cumulative CR was lower than the acceptable level (10−4), although individual CR for some metals exceeded the acceptable limit (10−6). In a lifetime the estimated number of attributable cancer cases was 74, 0.107, and 217 in Athens, Kuopio, and Lisbon, respectively. Excess risk-based mortality estimates (due to outdoor pollution) for fine particles were 3930, 44.1, and 2820 attributable deaths in Athens, Kuopio, and Lisbon, respectively.
Plum Rain-Season-Oriented Modelling and Intervention of Indoor Humidity with and without Human Occupancy
Authors: Ye Jin , Qian Hua , Zheng Xiaohong , Cao Guoqing
Published: February 2019

The plum rain season, caused by precipitation along a persistent stationary Mei-Yu front in East Asia, creates favorable temperatures and relative humidity (RH) for mold growth indoors. This paper investigates the effects of human occupancy on indoor humidity and investigates the efficient RH reduction methods to prevent mold growth in moist climates. The research is carried out based on a case study which compares a family-occupied home and another unoccupied one during typical plum rain season in Nanjing. Firstly, by analyzing the factors that can influence the indoor air RH, this paper develops a comprehensive model to evaluate the efficiency of various RH intervention methods. Secondly, this paper collects the meteorological data in Nanjing at different time scales, from days to hours. Thirdly, a specific case study is carried out based on the model and data. The results show that dehumidification and heating can always reduce RH below the critical value under which the mold growth could be inhibited. However, the effects of ventilation are more sophisticated and depend upon the human occupancy, outdoor air temperature, and air change per hour (ACH). In certain unoccupied cases, the ventilation may be inappropriate and may continuously bring moisture outside into the indoor environment, which has adverse effects on mold suppression. In the occupied cases, the condition changes significantly because the human is deemed as an internal source of heat and moist. Special care should be exercised for occupied ventilation in order to determine the optimal ACH and appropriate outdoor temperatures. Finally, some guidance is given to prevent mold growth in the general area that suffers from the plum rain season.
General Relativity with a Positive Cosmological Constant Λ as a Gauge Theory
Authors: Dudek Marta , Garecki Janusz
Published: February 2019

In this paper, we show that the general relativity action (and Lagrangian) in recent Einstein–Palatini formulation is equivalent in four dimensions to the action (and Langrangian) of a gauge field. First, we briefly showcase the Einstein–Palatini (EP) action, and then we present how Einstein fields equations can be derived from it. In the next section, we study Einstein–Palatini action integral for general relativity with a positive cosmological constant Λ in terms of the corrected curvature Ω c o r. We see that in terms of Ω c o r this action takes the form typical for a gauge field. Finally, we give a geometrical interpretation of the corrected curvature Ω c o r.
A One-Dimensional Stack Model for Redox Flow Battery Analysis and Operation
Authors: Barton John L. , Brushett Fikile R.
Published: February 2019

Current redox flow battery (RFB) stack models are not particularly conducive to accurate yet high-throughput studies of stack operation and design. To facilitate system-level analysis, we have developed a one-dimensional RFB stack model through the combination of a one-dimensional Newman-type cell model and a resistor-network to evaluate contributions from shunt currents within the stack. Inclusion of hydraulic losses and membrane crossover enables constrained optimization of system performance and allows users to make recommendations for operating flow rate, current densities, and cell design given a subset of electrolyte and electrode properties. Over the range of experimental conditions explored, shunt current losses remain small, but mass-transfer losses quickly become prohibitive at high current densities. Attempting to offset mass-transfer losses with high flow rates reduces system efficiency due to the increase in pressure drop through the porous electrode. The development of this stack model application, along with the availability of the source MATLAB code, allows for facile approximation of the upper limits of performance with limited empiricism. This work primarily presents a readily adaptable tool to enable researchers to perform either front-end performance estimates based on fundamental material properties or to benchmark their experimental results.
Testosterone in Males as Enhanced by Onion (Allium Cepa L.)
Authors: Banihani Saleem Ali
Published: February 2019

Testosterone (17β-Hydroxyandrost-4-en-3-one) is the main sex hormone in males. Maintaining and enhancing testosterone level in men is an incessant target for many researchers. Examples of such research approaches is to utilize specific types of food or dietary supplements as a safe and easily reached means. Here, specifically, since 1967 until now, many research studies have revealed the effect of onion on testosterone; however, this link has yet to be collectively reviewed or summarized. To accomplish this contribution, we searched the Scopus, Web of Science, and PubMed databases for full articles or abstracts (published in English language) from April 1967 through December 2018 using the keywords “onion” versus “testosterone”. In addition, a number of related published articles from the same databases were included to improve the integrity of the discussion, and hence the edge of the future directions. In summary, there is an evidence that onions enhance testosterone level in males. The mechanisms by which this occurs is mainly by increasing the production of luteinizing hormone, enhancing the antioxidant defense mechanism in the tests, neutralizing the damaging effects of the generated free radicals, ameliorating insulin resistance, promoting nitric oxide production, and altering the activity of adenosine 5′-monophosphate -activated protein kinase. However, this effect requires further approval in humans, mainly by conducting clinical trials.
Silver Nanoparticle-Induced Phosphorylation of Histone H3 at Serine 10 Involves MAPK Pathways
Authors: Zhao Xiaoxu , Rao Yanying , Liang Jie , Lin Shoukai , Wang Xiumei , Li Zhangliang , Huang Jianhui
Published: February 2019

The phosphorylation of histone H3 at serine 10 (p-H3S10) has been shown to be closely correlated with mitotic chromosome condensation. We previously reported that intracellular silver nanoparticles (AgNPs) release Ag ions that alter actin filament dynamics, leading to the activation of Aurora kinases and the formation of p-H3S10 through a mechanism clearly different from that occurring during mitosis. In the present study, we examined other mechanisms underlying the induction of p-H3S10 formation by AgNPs. We observed that the early formation of p-H3S10 induced by AgNPs occurred via the activation of mitogen-activated protein kinase (MAPK) pathways, specifically the Jun N-terminal protein kinase (JNK) and extracellular signal-regulated kinase (ERK) pathways. The late AgNP-induced p-H3S10 formation occurred via the activation of the entire MAPK cascade. On the other hand, p-H3S10 formation was not due to DNA damage induced by AgNPs, or the activation of the kinases ataxia telangiectasia-mutated (ATM) and ATM-Rad3-related (ATR). Several studies have compared the mechanism of AgNP toxicity to a Trojan horse-type molecular pathway. We observed different effects of AgNO3 (Ag+) and AgNPs on cells, and only the JNK inhibitor suppressed the temporary AgNO3-induced formation of p-H3S10. These results strongly indicate that AgNP-induced p-H3S10 formation does not rely solely on one signaling pathway, but rather may involve two or more pathways.
Rice Husk-Derived High Surface Area Nanoporous Carbon Materials with Excellent Iodine and Methylene Blue Adsorption Properties
Authors: Shrestha Lok Kumar , Thapa Mamata , Shrestha Rekha Goswami , Maji Subrata , Pradhananga Raja Ram , Ariga Katsuhiko
Published: February 2019

Iodine and methylene blue adsorption properties of the high surface area nanoporous carbon materials derived from agro-waste and rice husk is reported. Rice husk was pre-carbonized at 300 °C in air followed by leaching out the silica nanoparticles by extraction with sodium hydroxide solution. The silica-free rice husk char was mixed with chemical activating agents sodium hydroxide (NaOH), zinc chloride (ZnCl2), and potassium hydroxide (KOH) separately at a mixing ratio of 1:1 (wt%) and carbonized at 900 °C under a constant flow of nitrogen. The prepared carbon materials were characterized by scanning electron microscopy (SEM), Fourier transformed-infrared spectroscopy (FT-IR), powder X-ray diffraction (pXRD), and Raman scattering. Due to the presence of bimodal micro- and mesopore structures, KOH activated samples showed high specific surface area ca. 2342 m2/g and large pore volume ca. 2.94 cm3/g. Oxygenated surface functional groups (hydroxyl, carbonyl, and carboxyl) were commonly observed in all of the samples and were essentially non-crystalline porous particle size of different sizes (<200 μm). Adsorption study revealed that KOH activated samples could be excellent material for the iodine and methylene blue adsorption from aqueous phase. Iodine and methylene blue number were ca. 1726 mg/g and 608 mg/g, respectively. The observed excellent iodine and methylene blue adsorption properties can be attributed to the well-developed micro- and mesopore structure in the carbon material. This study demonstrates that the agricultural waste, rice husk, and derived nanoporous carbon materials would be excellent adsorbent materials in water purifications.
Trending Towards Safer Breast Cancer Surgeries? Examining Acute Complication Rates from A 13-Year NSQIP Analysis
Authors: Jonczyk Michael M. , Jean Jolie , Graham Roger , Chatterjee Abhishek
Published: February 2019

As breast cancer surgery continues to evolve, this study highlights the acute complication rates and predisposing risks following partial mastectomy (PM), mastectomy(M), mastectomy with muscular flap reconstruction (M + MF), mastectomy with implant reconstruction (M + I), and oncoplastic surgery (OPS). Data was collected from the American College of Surgeons NSQIP database (2005–2017). Complication rate and trend analyses were performed along with an assessment of odds ratios for predisposing risk factors using adjusted linear regression. 226,899 patients met the inclusion criteria. Complication rates have steadily increased in all mastectomy groups (p < 0.05). Cumulative complication rates between surgical categories were significantly different in each complication cluster (all p < 0.0001). Overall complication rates were: PM: 2.25%, OPS: 3.2%, M: 6.56%, M + MF: 13.04% and M + I: 5.68%. The most common predictive risk factors were mastectomy, increasing operative time, ASA class, BMI, smoking, recent weight loss, history of CHF, COPD and bleeding disorders (all p < 0.001). Patients who were non-diabetic, younger (age < 60) and treated as an outpatient all had protective OR for an acute complication (p < 0.0001). This study provides data comparing nationwide acute complication rates following different breast cancer surgeries. These can be used to inform patients during surgical decision making.
Casticin-Induced Inhibition of Cell Growth and Survival Are Mediated through the Dual Modulation of Akt/mTOR Signaling Cascade
Authors: Lee Jong Hyun , Kim Chulwon , Um Jae-Young , Sethi Gautam , Ahn Kwang Seok
Published: February 2019

The Akt/mTOR signaling cascade is a critical pathway involved in various physiological and pathological conditions, including regulation of cell proliferation, survival, invasion, and angiogenesis. In the present study, we investigated the anti-neoplastic effects of casticin (CTC), identified from the plant Vitex rotundifolia L., alone and/or in combination with BEZ-235, a dual Akt/mTOR inhibitor in human tumor cells. We found that CTC exerted a significant dose-dependent cytotoxicity and reduced cell proliferation in a variety of human tumor cells. Also, CTC effectively blocked the phosphorylation levels of Akt (Ser473) and mTOR (Ser2448) proteins as well as induced substantial apoptosis. Additionally treatment with CTC and BEZ-235 in conjunction resulted in a greater apoptotic effect than caused by either agent alone thus implicating the anti-neoplastic effects of this novel combination. Overall, the findings suggest that CTC can interfere with Akt/mTOR signaling cascade involved in tumorigenesis and can be used together with pharmacological agents targeting Akt/mTOR pathway.
Regulation of KIF2A by Antitumor miR-451a Inhibits Cancer Cell Aggressiveness Features in Lung Squamous Cell Carcinoma
Authors: Uchida Akifumi , Seki Naohiko , Mizuno Keiko , Yamada Yasutaka , Misono Shunsuke , Sanada Hiroki , Kikkawa Naoko , Kumamoto Tomohiro , Suetsugu Takayuki , Inoue Hiromasa
Published: February 2019

In the human genome, miR-451a is encoded close to the miR-144 on chromosome region 17q11.2. Our previous study showed that both strands of pre-miR-144 acted as antitumor miRNAs and were involved in lung squamous cell carcinoma (LUSQ) pathogenesis. Here, we aimed to investigate the functional significance of miR-451a and to identify its targeting of oncogenic genes in LUSQ cells. Downregulation of miR-451a was confirmed in LUSQ clinical specimens, and low expression of miR-451a was significantly associated with poor prognosis of LUSQ patients (overall survival: p = 0.035, disease-free survival: p = 0.029). Additionally, we showed that ectopic expression of miR-451a significantly blocked cancer cell aggressiveness. In total, 15 putative oncogenic genes were shown to be regulated by miR-451a in LUSQ cells. Among these targets, high kinesin family member 2A (KIF2A) expression was significantly associated with poor prognosis (overall survival: p = 0.043, disease-free survival: p = 0.028). Multivariate analysis showed that KIF2A expression was an independent prognostic factor in patients with LUSQ (hazard ratio = 1.493, p = 0.034). Aberrant KIF2A expression promoted the malignant transformation of this disease. Analytic strategies based on antitumor miRNAs and their target oncogenes are effective tools for identification of novel molecular pathogenesis of LUSQ.
Editorial Catalysts: Special Issue on Plasma Catalysis
Authors: Bogaerts Annemie
Published: February 2019

Plasma catalysis is gaining increasing interest for various gas conversion applications, such as CO2 conversion into value-added chemicals and fuels, N2 fixation for the synthesis of NH3 or NOx, and CH4 conversion into higher hydrocarbons or oxygenates [...]
Theoretical Study on Influence of Cobalt Oxides Valence State Change for C6H5COOH Pyrolysis
Authors: Fu Si-Mei , Zhao Yue , Liu Jiang-Tao , Liang Wen-Sheng , Li Gang-Sen , Huang Wei , Zuo Zhi-Jun
Published: February 2019

Benzoic acid (C6H5COOH) is selected as coal-based model compound with Co compounds (Co3O4, CoO and Co) as the catalysts, and the influence of the valence state change of the catalyst for pyrolysis process is investigated using density functional theory (DFT). DFT results shows that the highest energy barrier of C6H5COOH pyrolysis is in the following order: Ea(CoO) <Ea(Co3O4) <Ea(no catalyst) <Ea(Co). In general, Co3O4 catalyst accelerates C6H5COOH pyrolysis. Then, the catalytic activity further increases when Co3O4 is reduced to CoO. Finally, Co shows no activity for C6H5COOH pyrolysis due to the reduction of CoO to metallic Co.
The Support Effects on the Direct Conversion of Syngas to Higher Alcohol Synthesis over Copper-Based Catalysts
Authors: Li Xiaoli , Zhang Junfeng , Zhang Min , Zhang Wei , Zhang Meng , Xie Hongjuan , Wu Yingquan , Tan Yisheng
Published: February 2019

The types of supports employed profoundly influence the physicochemical properties and performances of as-prepared catalysts in almost all catalytic systems. Herein, Cu catalysts, with different supports (SiO2, Al2O3), were prepared by a facile impregnation method and used for the direct synthesis of higher alcohols from CO hydrogenation. The prepared catalysts were characterized using multiple techniques, such as X-ray diffraction (XRD), N2 sorption, H2-temperature-programmed reduction (H2-TPR), temperature-programmed desorption of ammonia (NH3-TPD), X-ray photoelectron spectroscopy (XPS) and in situ Fourier-transform infrared spectroscopy (FTIR), etc. Compared to the Cu/Al2O3 catalyst, the Cu/SiO2 catalyst easily promoted the formation of a higher amount of C1 oxygenate species on the surface, which is closely related to the formation of higher alcohols. Simultaneously, the Cu/Al2O3 and Cu/SiO2 catalysts showed obvious differences in the CO conversion, alcohol distribution, and CO2 selectivity, which were probably originated from differences in the structural and physicochemical properties, such as the types of copper species, the reduction behaviors, acidity, and electronic properties. Besides, it was also found that the gap in performances in two kinds of catalysts with the different supports could be narrowed by the addition of potassium because of its neutralization to surface acidy of Al2O3 and the creation of new basic sites, as well as the alteration of electronic properties.
Effect of Pt Promotion on the Ni-Catalyzed Deoxygenation of Tristearin to Fuel-Like Hydrocarbons
Authors: Loe Ryan , Huff Kelsey , Walli Morgan , Morgan Tonya , Qian Dali , Pace Robert , Song Yang , Isaacs Mark , Santillan-Jimenez Eduardo , Crocker Mark
Published: February 2019

Pt represents an effective promoter of supported Ni catalysts in the transformation of tristearin to green diesel via decarbonylation/decarboxylation (deCOx), conversion increasing from 2% over 20% Ni/Al2O3 to 100% over 20% Ni-0.5% Pt/Al2O3 at 260 °C. Catalyst characterization reveals that the superior activity of Ni-Pt relative to Ni-only catalysts is not a result of Ni particle size effects or surface area differences, but rather stems from several other phenomena, including the improved reducibility of NiO when Pt is present. Indeed, the addition of a small amount of Pt to the supported Ni catalyst dramatically increases the amount of reduced surface metal sites, which are believed to be the active sites for deCOx reactions. Further, Pt addition curbs the adsorption of CO on the catalyst surface, which decreases catalyst poisoning by any CO evolved via decarbonylation, making additional active sites available for deoxygenation reactions and/or preventing catalyst coking. Specifically, Pt addition weakens the Ni-CO bond, lowering the binding strength of CO on surface Ni sites. Finally, analysis of the spent catalysts recovered from deCOx experiments confirms that the beneficial effect of Pt on catalyst performance can be partially explained by decreased coking and fouling.