bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimization of Reflux Conditions for Total Flavonoid and Total Phenolic Extraction and Enhanced Antioxidant Capacity in Pandan (Pandanus amaryllifoliusRoxb.) Using Response Surface Methodology
Authors: Ghasemzadeh Ali , Jaafar Hawa Z. E.
Published: July 2014

Response surface methodology was applied to optimization of the conditions for reflux extraction of Pandan (Pandanus amaryllifoliusRoxb.) in order to achieve a high content of total flavonoids (TF), total phenolics (TP), and high antioxidant capacity (AC) in the extracts. Central composite experimental design with three factors and three levels was employed to consider the effects of the operation parameters, including the methanol concentration (MC, 40%–80%), extraction temperature (ET, 40–70°C), and liquid-to-solid ratio (LS ratio, 20–40 mL/g) on the properties of the extracts. Response surface plots showed that increasing these operation parameters induced the responses significantly. The TF content and AC could be maximized when the extraction conditions (MC, ET, and LS ratio) were 78.8%, 69.5°C, and 32.4 mL/g, respectively, whereas the TP content was optimal when these variables were 75.1%, 70°C, and 31.8 mL/g, respectively. Under these optimum conditions, the experimental TF and TP content and AC were 1.78, 6.601 mg/g DW, and 87.38%, respectively. The optimized model was validated by a comparison of the predicted and experimental values. The experimental values were found to be in agreement with the predicted values, indicating the suitability of the model for optimizing the conditions for the reflux extraction of Pandan.
The Numerical Investigation of Temperature and Velocity Distribution in the High-Bay Depot
Authors: Wu Xuehong , Dai Jianbiao , Meng Hao , Lu Yanli , Chang Zhijuan
Published: July 2014

High-bay depot plays an important role in the storage industry. Due to large and high space of high-bay depot, it is difficult to make temperature distribution uniform, which will influence the storage time of raw materials. In this paper, the aim is to find the reasonable air supply and energy-saving method; a supply-air method of high-bay depot is investigated as an example. The results show the radius and spacing of the supply-air inlet have great influence on temperature distribution. The temperature nonuniformity coefficient of summer is smaller than that of winter. The investigated results can provide a theoretical reference for the high-bay depot design and economic operation.
Artificial Fish Swarm Algorithm‐Based Particle Filter for Li‐Ion Battery Life Prediction
Authors: Tian Ye , Lu Chen , Wang Zili , Tao Laifa
Published: July 2014

An intelligent online prognostic approach is proposed for predicting the remaining useful life (RUL) of lithium‐ion (Li‐ion) batteries based on artificial fish swarm algorithm (AFSA) and particle filter (PF), which is an integrated approach combining model‐based method with data‐driven method. The parameters, used in the empirical model which is based on the capacity fade trends of Li‐ion batteries, are identified dependent on the tracking ability of PF. AFSA‐PF aims to improve the performance of the basic PF. By driving the prior particles to the domain with high likelihood, AFSA‐PF allows global optimization, prevents particle degeneracy, thereby improving particle distribution and increasing prediction accuracy and algorithm convergence. Data provided by NASA are used to verify this approach and compare it with basic PF and regularized PF. AFSA‐PF is shown to be more accurate and precise.
A Graph Embedding Method Based on Sparse Representation for Wireless Sensor Network Localization
Authors: Yan Xiaoyong , Song Aiguo , Yan Hao
Published: July 2014

In accordance with the problem that the traditional trilateral or multilateral estimation localization method is highly dependent on the proportion of beacon nodes and the measurement accuracy, an algorithm based on kernel sparse preserve projection (KSPP) is proposed in this dissertation. The Gaussian kernel function is used to evaluate the similarity between nodes, and the location of the unknown nodes will be commonly decided by all the nodes within communication radius through selection of sparse preserve projection self-adaptation and maintaining of the topological structure between adjacent nodes. Therefore, the algorithm can effectively solve the nonlinear problem while ranging, and it becomes less affected by the measuring error and beacon nodes quantity.
A New Approach to Entropy and Similarity Measure of Vague Soft Sets
Authors: Hu Dan , Hong Zhiyong , Wang Yong
Published: July 2014

We focus our discussion on the uncertainty measures of vague soft sets. We propose axiomatic definitions of similarity measure and entropy for vague soft sets. Furthermore, we present a new category of similarity measures and entropies for vague soft sets. The basic properties of these measures are discussed and the relationships among these measures are analyzed.
Research on MAS-Based Supply Chain Resilience and Its Self-Organized Criticality
Authors: Geng Liang , Xiao Renbin , Xu Xing
Published: July 2014

Building resilient supply chain is an effective way to deal with uncertain risks. First, by analyzing the self-organization of supply chain, the supply chain resilience is described as a macroscopic property that generates from self-organizing behavior of each enterprise on the microlevel. Second, a MAS-based supply chain resilience model is established and its local fitness function, neighborhood structure, and interaction rules that are applicable to supply chain system are designed through viewing the enterprise as an agent. Finally, with the help of a case, we find that there is an agglomeration effect and a SOC characteristic in supply chain and the evolution of supply chain is controlled by parameters of MAS. Managers can control the supply chain within the resilient range and choose a good balance between interest and risk by controlling enterprises’ behavior.
Nonlinear Finite Element Analysis of the Fluted Corrugated Sheet in the Corrugated Cardboard
Authors: Zhang Zhiguo , Qiu Tao , Song Riheng , Sun Yaoyu
Published: July 2014

The choice of corrugated medium, flute size, combining adhesive, and linerboards can be varied to design a corrugated board with specific properties. In this paper, the nonlinear finite element analysis of the fluted corrugated sheet in the corrugated cardboard based on software SolidWorks2008 was investigated. The model of corrugated board with three or more flutes is reliable for stress and displacement measurement to eliminate the influence of the number of flutes in models. According to the static pressure test, with the increase of flute heightHor arc radius of flute, the maximum stress in the models decreased and the maximum displacement increased. However the maximum stress and maximum displacement in the models increase nonlinearly in the static pressure test with the increase of the flute angleθ. According to the drop test, with the increase of flute heightH, the maximum stress of goods on the upper board in the drop test decreased. The maximum stress of the model in the drop test decreases firstly and then increases with the increase of flute angle, and the optimal flute angleθcould be 60° for corrugated board. All the conclusions are consistent with experimental data or product standards.
A Passive Harmonic Tag for Humidity Sensing
Authors: Lazaro Antonio , Villarino Ramon , Girbau David
Published: July 2014

This paper describes a passive harmonic tag for radio frequency identification (RFID) and wireless sensor applications. The tag uses a dual polarized UHF patch antenna as an input antenna. One of the outputs is connected to a frequency doubler, which consists of a Schottky diode with its output connected to a patch tuned at twice the input frequency. The other output of the input antenna feeds a DC power harvested converter that drives an oscillator which modulates its output signal by controlling the bias point of the Schottky diode. The antenna’s output is also used as a humidity sensor. To achieve this, the antenna is loaded with an interdigital capacitor with humidity-dependent capacitance. The antenna is consequently detuned when humidity varies, and therefore the second harmonic power is received. The tag is manufactured using standard fiberglass substrate. The basic theory of harmonic tag operation is described and compared with the standard backscattering approach. Experimental results with a proof of concept using commercial components are presented.
Due Date Single Machine Scheduling Problems with Nonlinear Deterioration and Learning Effects and Past Sequence Dependent Setup Times
Authors: Ceylan Hüseyin
Published: July 2014

We present some problems against due dates with nonlinear learning and deterioration effects and past sequence dependent setup times. In this study, two effects (learning and deterioration) are used for the same processing time. The processing time of a job is shorter if it is scheduled later, rather than in the sequence. This phenomenon is known in the literature as a “learning effect.” On the other hand, in many realistic scheduling settings, a job processed later consumes more time than the same job processed earlier—this is known as scheduling with deteriorating jobs. In the past sequence dependent setup times approach, the setup time of a job is proportionate to the sum of processing times of the jobs already scheduled. In this study, we demonstrated that some problems with due dates remain polynomially solvable. However, for some other problems, we concentrated on finding polynomially solves under their special cases.
A Proactive Approach of Robotic Framework for Making Eye Contact with Humans
Authors: Hoque Mohammed Moshiul , Kobayashi Yoshinori , Kuno Yoshinori
Published: July 2014

Making eye contact is a most important prerequisite function of humans to initiate a conversation with others. However, it is not an easy task for a robot to make eye contact with a human if they are not facing each other initially or the human is intensely engaged his/her task. If the robot would like to start communication with a particular person, it should turn its gaze to that person and make eye contact with him/her. However, such a turning action alone is not enough to set up an eye contact phenomenon in all cases. Therefore, the robot should perform some stronger actions in some situations so that it can attract the target person before meeting his/her gaze. In this paper, we proposed a conceptual model of eye contact for social robots consisting of two phases: capturing attention and ensuring the attention capture. Evaluation experiments with human participants reveal the effectiveness of the proposed model in four viewing situations, namely, central field of view, near peripheral field of view, far peripheral field of view, and out of field of view.
Pawlak Algebra and Approximate Structure on Fuzzy Lattice
Authors: Zhuang Ying , Liu Wenqi , Wu Chin-Chia , Li Jinhai
Published: July 2014

The aim of this paper is to investigate the general approximation structure, weak approximation operators, and Pawlak algebra in the framework of fuzzy lattice, lattice topology, and auxiliary ordering. First, we prove that the weak approximation operator space forms a complete distributive lattice. Then we study the properties of transitive closure of approximation operators and apply them to rough set theory. We also investigate molecule Pawlak algebra and obtain some related properties.
Preparation and Rheological Characterization of Imogolite Hydrogels
Authors: Fujikura Kie , Maeda Hirotaka , Obata Akiko , Inukai Keiichi , Kato Katsuya , Kasuga Toshihiro
Published: July 2014

Imogolite, one of the aluminium silicates, has a nanotube structure and has been known to form gel under alkaline condition. Imogolite nanotubes were synthesized in an acidic solution with various tube lengths by controlling the aging time from 1 d to 14 d. The length of the nanotubes grew from 100 nm to several μm as the aging time. Pure imogolite hydrogels were prepared by applying a salting‐out method and centrifugation from its dispersed solutions with various tube lengths and solution pH. Imogolite hydrogel can be classified as the physically cross‐linked one; the structure of the gel network is considered to be the entanglements and hydrogen bonding among nanotubes. The theoretical water contents of the prepared hydrogels were calculated as ∼99.7% in average. Gelation percentage significantly increased as the length of imogolite nanotubes. Whereas hydrogel prepared from 4 d aging sample showed the highest storage modulus of ∼970 Pa, it was found that the hydrogel could be prepared in the pH range from 6 to 10. The gel strength reached the highest value of 1000 Pa when the gel was prepared from the imogolite dispersed solution of pH 8. It could be explained by the surface charge variation of the imogolite.
Drag Reduction by Microvortexes in Transverse Microgrooves
Authors: Wang Bao , Wang Jiadao , Zhou Gang , Chen Darong
Published: July 2014

A transverse microgrooved surface was employed here to reduce the surface drag force by creating a slippage in bottom layer in turbulent boundary layer. A detailed simulation and experimental investigation on drag reduction by transverse microgrooves were given. The computational fluid dynamics simulation, using RNG k- ε turbulent model, showed that the vortexes were formed in the grooves and they were a main reason for the drag reduction. On the upside of the vortex, the revolving direction was consistent with the main flow, which decreased the flow shear stress by declining the velocity gradient. The experiments were carried out in a high-speed water tunnel with flow velocity varying from 17 to 19 m/s. The experimental results showed that the drag reduction was about 13%. Therefore, the computational and experimental results were cross-checked and consistent with each other to prove that the presented approach achieved effective drag reduction underwater.
Accurate Evaluation of Polynomials in Legendre Basis
Authors: Du Peibing , Jiang Hao , Cheng Lizhi
Published: July 2014

This paper presents a compensated algorithm for accurate evaluation of a polynomial in Legendre basis. Since the coefficients of the evaluated polynomial are fractions, we propose to store these coefficients in two floating point numbers, such as double-double format, to reduce the effect of the coefficients’ perturbation. The proposed algorithm is obtained by applying error-free transformation to improve the Clenshaw algorithm. It can yield a full working precision accuracy for the ill-conditioned polynomial evaluation. Forward error analysis and numerical experiments illustrate the accuracy and efficiency of the algorithm.
On Thompson’s Conjecture for Alternating GroupsAp+3
Authors: Liu Shitian , Yang Yong
Published: July 2014

LetGbe a group. Denote byπ(G)the set of prime divisors of|G|. LetGK(G)be the graph with vertex setπ(G)such that two primespandqinπ(G)are joined by an edge ifGhas an element of orderp·q. We sets(G)to denote the number of connected components of the prime graphGK(G). Denote byN(G)the set of nonidentity orders of conjugacy classes of elements inG. Alavi and Daneshkhah proved that the groups,Anwheren=p,p+1,p+2withs(G)≥2, are characterized byN(G). As a development of these topics, we will prove that ifGis a finite group with trivial center andN(G)=N(Ap+3)withp+2composite, thenGis isomorphic toAp+3.
Association between Serum Uric Acid Level and Metabolic Syndrome and Its Sex Difference in a Chinese Community Elderly Population
Authors: Liu Miao , He Yao , Jiang Bin , Wu Lei , Yang Shanshan , Wang Yiyan , Li Xiaoying
Published: July 2014

Objective. This study aimed to evaluate the association between serum uric acid (SUA) levels within a normal to high range and the risk of metabolic syndrome (MetS) among community elderly and explore the sex difference.Design and Methods. A cross-sectional study was conducted in a representative urban area of Beijing between 2009 and 2010. A two-stage stratified clustering sampling method was used and 2102 elderly participants were included.Results. The prevalence of hyperuricemia and MetS was 16.7% and 59.1%, respectively. There was a strong association between hyperuricemia and four components of MetS in women and three components in men. Multiple logistic regression analysis showed ORs of hyperuricemia for MetS were 1.67 (95% CI: 1.11–2.50) in men and 2.73 (95% CI: 1.81–4.11) in women. Even in the normal range, the ORs for MetS increased gradually according to SUA levels. MetS component number also showed an increasing trend across SUA quartile in both sexes (Pfor trend < 0.01).Conclusion. This study suggests that higher SUA levels, even in the normal range, are positively associated with MetS among Chinese community elderly, and the association is stronger in women than men. Physicians should recognize MetS as a frequent comorbidity of hyperuricemia and take early action to prevent subsequent disease burden.
Distribution, Microfabric, and Geochemical Characteristics of Siliceous Rocks in Central Orogenic Belt, China: Implications for a Hydrothermal Sedimentation Model
Authors: Li Hongzhong , Zhai Mingguo , Zhang Lianchang , Gao Le , Yang Zhijun , Zhou Yongzhang , He Junguo , Liang Jin , Zhou Liuyu , Voudouris Panagiotis Ch.
Published: July 2014

Marine siliceous rocks are widely distributed in the central orogenic belt (COB) of China and have a close connection to the geological evolution and metallogenesis. They display periodic distributions from Mesoproterozoic to Jurassic with positive peaks in the Mesoproterozoic, Cambrian—Ordovician, and Carboniferous—Permian and their deposition is enhanced by the tensional geological settings. The compressional regimes during the Jinning, Caledonian, Hercynian, Indosinian, and Yanshanian orogenies resulted in sudden descent in their distribution. The siliceous rocks of the Bafangshan-Erlihe ore deposit include authigenic quartz, syn-depositional metal sulphides, and scattered carbonate minerals. Their SiO2content (71.08–95.30%), Ba (42.45–503.0 ppm), and ΣREE (3.28–19.75 ppm) suggest a hydrothermal sedimentation origin. As evidenced by the Al/(Al + Fe + Mn), Sc/Th,(La/Yb)N, and(La/Ce)Nratios andδCe values, the studied siliceous rocks were deposited in a marginal sea basin of a limited ocean. We suggest that the Bafangshan-Erlihe area experienced high- and low-temperature stages of hydrothermal activities. The hydrothermal sediments of the former stage include metal sulphides and silica, while the latter was mainly composed of silica. Despite the hydrothermal sedimentation of the siliceous rocks, minor terrigenous input, magmatism, and biological activity partly contributed to geochemical features deviating from the typical hydrothermal characteristics.
Micro- and Macroelemental Composition and Safety Evaluation of the NutraceuticalMoringa oleiferaLeaves
Authors: Asiedu-Gyekye I. J. , Frimpong-Manso S. , Awortwe C. , Antwi D. A. , Nyarko A. K.
Published: July 2014

Moringa oleiferais a multipurpose plant used in Ghana and most parts of Africa. Its high mineral, protein, and vitamins content has enabled its use as a nutraceutical and panacea for various diseases. This study aimed at measuring the micro- and macroelements content of driedMoringa oleiferaleaves using energy dispersive X-ray fluorescence spectroscopic (EDXRF) and assessing its toxicological effect in rats. Acute toxicity (5000 mg/kg) and a subacute toxicity studies of the leaf (40 mg/kg to 1000 mg/kg) extract were conducted in rats. Blood samples were assessed for biochemical and haematological parameters. Results showed significant levels of thirty-five (35) elements (14 macroelements and 21 microelements) inM. oleiferaextract. There were no observed overt adverse reactions in the acute and subacute studies. Although there were observed elevations in liver enzymes ALT and ALP(P<0.001)and lower creatinine levels in the extract treated groups, no adverse histopathological findings were found.Moringa oleiferadried leaf extract may, therefore, be reasonably safe for consumption. However, the consumption ofMoringa oleiferaleaves should not exceed a maximum of 70 grams per day to prevent cumulative toxicity of these essential elements over long periods.
Mandibular Atrophy and Genial Spines Enlargement on Cone Beam Computed Tomography
Authors: Poleti Marcelo Lupion , Oliveira-Santos Christiano , Paes da Silva Ramos Fernandes Luciana Maria , Rubira-Bullen Izabel Regina Fischer
Published: July 2014

Purpose. The aim of this paper is to report a case in which the cone beam computed tomography (CBCT) was important for the confirmation of the presence of mandibular atrophy and genial spines enlargement.Case Description. A 76-year-old female patient was referred for the assessment due to the complaint of chronic trauma in the anterior region of the floor of the mouth, which had been present for 2 months. CBCT images showed severe resorption of alveolar ridge and genial spines enlargement (5.5 mm × 12 mm).Conclusion. Accurate imaging assessment with the aid of 3D reconstructions allows the elimination of image superimposition and, therefore, plays an important role in the depiction of anatomical and pathological conditions, such as genial spines enlargement.
Effect of Cosolutes on the Sorption of Phenanthrene onto Mineral Surface of River Sediments and Kaolinite
Authors: Wu Yinghong , Liu Fang , Zhang Wen , Wang Lei
Published: July 2014

Sorption of phenanthrene onto the natural sediment with low organic carbon content (OC%), organic-free sediment, and kaolinite was investigated through isotherm experiments. Effects of cosolutes (pyrene, 4-n-nonyphenol (NP), and humic acid (HA)) on phenanthrene sorption were also studied by comparing apparent solid-water distribution coefficients (Kdapp) of phenanthrene. Two addition sequences, including “cosolute added prior to phenanthrene” and “cosolute and phenanthrene added simultaneously,” were adopted. The Freundlich model fits phenanthrene sorption on all 3 sorbents well. The sorption coefficients on these sorbents were similar, suggesting that mineral surface plays an important role in the sorption of hydrophobic organic contaminants on low OC% sediments. Cosolutes could affect phenanthrene sorption on the sorbents, which depended on their properties, concentrations, and addition sequences. Pyrene inhibited phenanthrene sorption. Sorbed NP inhibited phenanthrene sorption at low levels and promoted sorption at high levels. Similar to NP, effect of HA on phenanthrene sorption onto the natural sediment depended on its concentrations, whereas, for the organic-free sediment and kaolinite, preloading of HA at high levels led to an enhancement in phenanthreneKdappwhile no obvious effect was observed at low HA levels; dissolved HA could inhibit phenanthrene sorption on the two sorbents.
Comparison of a Fuzzy Genetic and Simulated Annealing Algorithm Approach for Project Time-Cost Tradeoff
Authors: Glišović Nataša
Published: July 2014

Project planning, defining the limitations and resources by leveling the resources available, have a great importance for the management projects. All these activities directly affect the duration and the cost of the project. To get a competitive value on the market, the project must be completed at the optimum time. In other to be competitive enough the optimum or near optimum solutions of time cost tradeoff and the resource leveling and resource constrained scheduling problems should be obtained in the planning phase of the project. One important aspect of the project management is activity crashing, that is, reducing activity time by adding more resources such as workers and overtime. It is important to decide the optimal crash plan to complete the project within the desired time period. The comparison of fuzzy simulated annealing and the genetic algorithm based on the crashing method is introduced in this paper to evaluate project networks and determine the optimum crashing configuration that minimizes the average project cost, caused by being late and crashing costs in the presence of vagueness and uncertainty. The evaluation results based on a real case study indicate that the method can be reliably applied to engineering projects.
Numerical Experiments for Nuclear Flashes toward Superbursts in an Accreting Neutron Star
Authors: Hashimoto Masa-aki , Kuromizu Reiko , Ono Masaomi , Noda Tsuneo , Fujimoto Masayuki Y.
Published: July 2014

We show that the superburst would be originated from thermonuclear burning ignited by accumulated fuels in the deep layers compared to normal X-ray bursts. Two cases are investigated for models related to superbursts by following thermal evolution of a realistic neutron star: helium flash and carbon flash accompanied with many normal bursts. For a helium flash, the burst shows the long duration when the accretion rate is low compared with the observation. The flash could become a superburst if the burning develops to the deflagration and/or detonation. For a carbon flash accompanied with many normal bursts, after successive 2786 normal bursts during 1.81 × 109 s, the temperature reaches the deflagration temperature. This is due to the produced carbon which amount reaches to ≈0.1 in the mass fraction. The flash will develop to dynamical phenomena of the deflagration and/or detonation, which may lead to a superburst.
Working Characteristics of a Mechanical Insufflation‐Exsufflation Device
Authors: Shi Yan , Ren Shuai , Cai Maolin , Xu Weiqing
Published: July 2014

Secretions of ventilated patients must be cleared efficiently and timely; to improve the secretion clearance efficiency of an insufflation‐exsufflation device (IL‐IE device) and lay a foundation for the optimization of the IL‐IE device, a mathematical model of the ventilation system with the IL‐IE device is set up. Through the experimental and simulation research on the ventilation system, it can be concluded that, firstly, the mathematical model is proved to be authentic and reliable. Secondly, with the deposition of secretion or an increase in the respiratory compliance, the peak exsufflation airflow may be reduced. Thirdly, with a decrease in the suction pressure, the peak exsufflation airflow of the ventilated lung may rise proportionally, but the minimum pressure in the ventilated lung may descend proportionally. To improve the efficiency of the secretion clearance but not to injure the ventilated patient, the suction pressure can be elevated properly. Last, increasing the inspiratory positive airway pressure (IPAP) is a method to improve the secretion clearance efficiency. This research lays a foundation for improving the secretion clearance efficiency of the IL‐IE device.
Chaotic Behaviors of Symbolic Dynamics about Rule 58 in Cellular Automata
Authors: Pei Yangjun , Han Qi , Liu Chao , Tang Dedong , Huang Junjian
Published: July 2014

The complex dynamical behaviors of rule 58 in cellular automata are investigated from the viewpoint of symbolic dynamics. The rule is Bernoulli στ‐shift rule, which is members of Wolfram’s class II, and it was said to be simple as periodic before. It is worthwhile to study dynamical behaviors of rule 58 and whether it possesses chaotic attractors or not. It is shown that there exist two Bernoulli‐measure attractors of rule 58. The dynamical properties of topological entropy and topological mixing of rule 58 are exploited on these two subsystems. According to corresponding strongly connected graph of transition matrices of determinative block systems, we divide determinative block systems into two subsets. In addition, it is shown that rule 58 possesses rich and complicated dynamical behaviors in the space of bi‐infinite sequences. Furthermore, we prove that four rules of global equivalence class of CA are topologically conjugate. We use diagrams to explain the attractors of rule 58, where characteristic function is used to describe that some points fall into Bernoulli‐shift map after several times iterations, and we find that these attractors are not global attractors. The Lameray diagram is used to show clearly the iterative process of an attractor.
Human Umbilical Cord Perivascular Cells Exhibited Enhanced Migration Capacity towards Hepatocellular Carcinoma in Comparison with Bone Marrow Mesenchymal Stromal Cells: A Role for Autocrine Motility Factor Receptor
Authors: Bayo Juan , Fiore Esteban , Aquino Jorge B. , Malvicini Mariana , Rizzo Manglio , Peixoto Estanislao , Alaniz Laura , Piccioni Flavia , Bolontrade Marcela , Podhajcer Osvaldo , Garcia Mariana G. , Mazzolini Guillermo
Published: July 2014

Hepatocellular carcinoma (HCC) is the third cause of cancer-related death worldwide. Unfortunately, the incidence and mortality associated with HCC are increasing. Therefore, new therapeutic strategies are urgently needed and the use of mesenchymal stromal cells (MSCs) as carrier of therapeutic genes is emerging as a promising option. Different sources of MSCs are being studied for cell therapy and bone marrow-derived cells are the most extensively explored; however, birth associated-tissues represent a very promising source. The aim of this work was to compare thein vitroandin vivomigration capacity between bone marrow MSCs (BM-MSCs) and human umbilical cord perivascular cells (HUCPVCs) towards HCC. We observed that HUCPVCs presented higherin vitroandin vivomigration towards factors released by HCC. The expression of autocrine motility factor (AMF) receptor, genes related with the availability of the receptor on the cell surface (caveolin-1 and -2) and metalloproteinase 3, induced by the receptor activation and important for cell migration, was increased in HUCPVCs. The chemotactic response towards recombinant AMF was increased in HUCPVCs compared to BM-MSCs, and its inhibition in the conditioned medium from HCC induced higher decrease in HUCPVC migration than in BM-MSC. Our results indicate that HUCPVCs could be a useful cellular source to deliver therapeutic genes to HCC.
Increasing the Capacity of Existing Bridges by Using Unbonded Prestressing Technology: A Case Study
Authors: Recupero Antonino , Spinella Nino , Colajanni Piero , Scilipoti Cosimo D.
Published: July 2014

External posttensioning or unbonded prestressing was found to be a powerful tool for retrofitting and for increasing the life extension of existing structures. Since the 1950s, this technique of reinforcement was applied with success to bridge structures in many countries, and was found to provide an efficient and economic solution for a wide range of bridge types and conditions. Unbonded prestressing is defined as a system in which the post-tensioning tendons or bars are located outside the concrete cross-section and the prestressing forces are transmitted to the girder through the end anchorages, deviators, or saddles. In response to the demand for a faster and more efficient transportation system, there was a steady increase in the weight and volume of traffic throughout the world. Besides increases in legal vehicle loads, the overloading of vehicles is a common problem and it must also be considered when designing or assessing bridges. As a result, many bridges are now required to carry loads significantly greater than their original design loads; and their deck results still deteriorated by cracking of concrete, corrosion of rebars, snapping of tendons, and so forth. In the following, a case study about a railway bridge retrofitted by external posttensioning technique will be illustrated.
Baicalein Protects against Type 2 Diabetes via Promoting Isletβ-Cell Function in Obese Diabetic Mice
Authors: Fu Yu , Luo Jing , Jia Zhenquan , Zhen Wei , Zhou Kequan , Gilbert Elizabeth , Liu Dongmin
Published: July 2014

In both type 1 (T1D) and type 2 diabetes (T2D), the deterioration of glycemic control over time is primarily caused by an inadequate mass and progressive dysfunction ofβ-cell, leading to the impaired insulin secretion. Here, we show that dietary supplementation of baicalein, a flavone isolated from the roots of Chinese herbScutellaria baicalensis, improved glucose tolerance and enhanced glucose-stimulated insulin secretion (GSIS) in high-fat diet (HFD-) induced middle-aged obese mice. Baicalein had no effect on food intake, body weight gain, circulating lipid profile, and insulin sensitivity in obese mice. Using another mouse model of type 2 diabetes generated by high-fat diet (HFD) feeding and low doses of streptozotocin injection, we found that baicalein treatment significantly improved hyperglycemia, glucose tolerance, and blood insulin levels in these middle-aged obese diabetic mice, which are associated with the improved isletβ-cell survival and mass. In thein vitrostudies, baicalein significantly augmented GSIS and promoted viability of insulin-secreting cells and human islets cultured either in the basal medium or under chronic hyperlipidemic condition. These results demonstrate that baicalein may be a naturally occurring antidiabetic agent by directly modulating pancreaticβ-cell function.
Arsenic Removal from Natural Groundwater by Electrocoagulation Using Response Surface Methodology
Authors: García-Lara A. M. , Montero-Ocampo C. , Equihua-Guillen F. , Camporredondo-Saucedo J. E. , Servin-Castaneda R. , Muñiz-Valdes C. R.
Published: July 2014

Contamination of natural groundwater by arsenic (As) is a serious problem that appears in some areas of Northern Central Mexico (NCM). In this research, As was removed from NCM wells groundwater by the electrocoagulation (EC) technique. Laboratory-scale arsenic electroremoval experiments were carried out at continuous flow rates between 0.25 and 1.00 L min−1using current densities of 5, 10, and 20 A m−2. Experiments were performed under galvanostatic conditions during 5 min, at constant temperature and pH. The response surface methodology (RSM) was used for the optimization of the processing variables (flow rate and current density), response modeling, and predictions. The highest arsenic removal efficiency from underground water (99%) was achieved at low flow rates (0.25 L min−1) and high current densities (20 A m−2). The response models developed explained 93.7% variability for As removal efficiency.
Synthesis and Characterization of CZTS Thin Films by Sol-Gel Method without Sulfurization
Authors: Yu Xiaoqi , Ren Aobo , Wang Fogen , Wang Ci , Zhang Jingquan , Wang Wenwu , Wu Lili , Li Wei , Zeng Guanggen , Feng Lianghuan
Published: July 2014

One process of layer-by-layer sol-gel deposition without sulfurization was developed. The CZTS films with 1.2 μm and the sulfur ratio of ~48% were prepared and their characteristics were measured. The as-deposited and annealed films are of Kesterite structure. The as-deposited films do not present obvious electric conduction type. However, the annealed 9-LAY-ANN film is p-type conduction and has sheet resistance of 4.08 kΩ/□ and resistivity of 4.896 × 10−1 Ω·cm. The optic energy gap is 1.50 eV for as-deposited films and is 1.46 eV after being annealed. The region deposited by using Lo-Con solution is more compact than that by the Hi-Con solution from SEM morphology images.
Research on Multirobot Pursuit Task Allocation Algorithm Based on Emotional Cooperation Factor
Authors: Fang Baofu , Chen Lu , Wang Hao , Dai Shuanglu , Zhong Qiubo
Published: July 2014

Multirobot task allocation is a hot issue in the field of robot research. A new emotional model is used with the self-interested robot, which gives a new way to measure self-interested robots’ individual cooperative willingness in the problem of multirobot task allocation. Emotional cooperation factor is introduced into self-interested robot; it is updated based on emotional attenuation and external stimuli. Then a multirobot pursuit task allocation algorithm is proposed, which is based on emotional cooperation factor. Combined with the two-step auction algorithm recruiting team leaders and team collaborators, set up pursuit teams, and finally use certain strategies to complete the pursuit task. In order to verify the effectiveness of this algorithm, some comparing experiments have been done with the instantaneous greedy optimal auction algorithm; the results of experiments show that the total pursuit time and total team revenue can be optimized by using this algorithm.
A Novel Double-Piston Magnetorheological Damper for Space Truss Structures Vibration Suppression
Authors: Wang Qiang , Ahmadian Mehdi , Chen Zhaobo
Published: July 2014

The design, fabrication, and testing of a new double-piston MR damper for space applications are discussed. The design concept for the damper is described in detail. The electromagnetic analysis of the design and the fabrication of the MR damper are also presented. The design analysis shows that the damper meets the weight and size requirements for being included in a space truss structure. The prototype design is tested in a damper dynamometer. The test results show that the damper can provide nearly 80 N of damping force at its maximum velocity and current. The test results also show that the seal drag could contribute significantly to the damping forces. Additionally, the test results indicate that both the work by the damper and damping force increase rapidly with increasing current at lower currents and taper off at higher currents as the damper starts to saturate. The damper force versus velocity plots show hysteresis in both pre- and postyield regions and asymmetric forces in jounce and rebound. A model is proposed for representing the force-displacement, force-velocity, and asymmetric forces observed in test results. A comparison of the modeling results and test data indicates that the model accurately represents the force characteristics of the damper.
A Single RF MIMO Loading Network for High-Order Modulation Schemes
Authors: Han Bo , Barousis Vlasis I. , Kalis Antonis , Papadias Constantinos B. , Kanatas Athanasios G. , Prasad Ramjee
Published: July 2014

Recently, a novel MIMO transmitter architecture has been introduced that requires only a single radio-frequency (RF) chain and is built on parasitic antenna arrays. MIMO transmission in this case is achieved by shaping directly the radiation pattern with the aid of analog tunable loads attached to the parasitics. As it has been shown, such a single RF MIMO system can support all PSK modulation formats with purely imaginary loading values. This paper extends its capabilities and proposes a novel architecture for parasitic antennas that is able to providecomplexloading values, even with a negative real part. Definitely, this will extend the flexibility of parasitic antennas to multiplex successfully over the air more complex signaling formats, for example, QAM signals. The bit error rate evaluation shows that the proposed architecture could be very promising in emerging devices and also illustrates its robustness under possible loading perturbations that might have been raised due to nonidealities in the design.
Middle-Ear Microsurgery Simulation to Improve New Robotic Procedures
Authors: Kazmitcheff Guillaume , Nguyen Yann , Miroir Mathieu , Péan Fabien , Ferrary Evelyne , Cotin Stéphane , Sterkers Olivier , Duriez Christian
Published: July 2014

Otological microsurgery is delicate and requires high dexterity in bad ergonomic conditions. To assist surgeons in these indications, a teleoperated system, called RobOtol, is developed. This robot enhances gesture accuracy and handiness and allows exploration of new procedures for middle ear surgery. To plan new procedures that exploit the capacities given by the robot, a surgical simulator is developed. The simulation reproduces with high fidelity the behavior of the anatomical structures and can also be used as a training tool for an easier control of the robot for surgeons. In the paper, we introduce the middle ear surgical simulation and then we perform virtually two challenging procedures with the robot. We show how interactive simulation can assist in analyzing the benefits of robotics in the case of complex manipulations or ergonomics studies and allow the development of innovative surgical procedures. New robot-based microsurgical procedures are investigated. The improvement offered by RobOtol is also evaluated and discussed.
Decreased Gastric Motility in Type II Diabetic Patients
Authors: Chiu Yi-Chun , Kuo Ming-Chun , Rayner Christopher K. , Chen Jung-Fu , Wu Keng-Liang , Chou Yeh-Pin , Tai Wei-Chen , Hu Ming-Luen
Published: July 2014

Background. To differentiate gastric motility and sensation between type II diabetic patients and controls and explore different expressions of gastric motility peptides.Methods. Eleven type II diabetic patients and health volunteers of similar age and body mass index were invited. All underwent transabdominal ultrasound for gastric motility and visual analogue scales. Blood samples were taken for glucose and plasma peptides (ghrelin, motilin, and glucacon-like peptides-1) by ELISA method.Results. Gastric emptying was significantly slower in diabetic patients than controls (T50: 46.3 (28.0–52.3) min versus 20.8 (9.6–22.8) min,P≤0.05) and less antral contractions in type II diabetic patients were observed(P=0.02). Fundus dimensions did not differ. There were a trend for less changes in gastrointestinal sensations in type II diabetic patients especially abdomen fullness, hunger, and abdominal discomfort. Although the serum peptides between the two groups were similar a trend for less serum GLP-1in type II diabetic patients was observed(P=0.098).Conclusion. Type II diabetic patients have delayed gastric emptying and less antral contractions than controls. The observation that there were lower serum GLP-1 in type II diabetic patients could offer a clue to suggest that delayed gastric emptying in diabetic patients is not mainly influenced by GLP-1.
Linguistic Modeling of Pressure Signal in Compressor and Application in Aerodynamic Instability Prediction
Authors: Sheng Hanlin , Huang Wei , Zhang Tianhong , Huang Xianghua
Published: July 2014

Using conditional fuzzy clustering, a linguistic model for static pressure signal of compressor outlet in aeroengine was established. The modeling process and the validation result demonstrated unique advances of linguistic modeling in the analysis of complex systems. The linguistic model was used to predict the pressure signal before the engine entered instability. The prediction result showed that the linguistic model could effectively recognize the sudden changes of pressure signal features. The detected change of signal might not necessarily be the commonly considered initial disturbance of compressor instability; however, the pattern recognition ability of linguistic model was still very attractive. At last, it pointed out that setting up a database containing experiment data and historical experience about engine aerodynamic instability and utilizing advanced intelligent computing technology in the database to develop knowledge discovery provide a new idea for the solution to the problem of aerodynamic instability in aeroengine.
Optimal Polynomial Decay to Coupled Wave Equations and Its Numerical Properties
Authors: Lobato R. F. C. , Cordeiro S. M. S. , Santos M. L. , Júnior D. S. Almeida
Published: July 2014

In this work we consider a coupled system of two weakly dissipative wave equations. We show that the solution of this system decays polynomially and the decay rate is optimal. Computational experiments are conducted in the one-dimensional case in order to show that the energies properties are preserved. In particular, we use finite differences and also spectral methods.
A Computationally Efficient Iterative Algorithm for Estimating the Parameter of Chirp Signal Model
Authors: Bian Jiawen , Xing Jing , Liu Zhihui , Fu Lihua , Li Hongwei
Published: July 2014

The parameter estimation of Chirp signal model in additive noises when all the noises are independently and identically distributed (i.i.d.) has been considered. A novel iterative algorithm is proposed to estimate the frequency rate of the considered model by constructing the iterative statistics with one-lag and multilag differential signals. It is observed that the estimator for the iterative algorithm is consistent and works quite well in terms of biases and mean squared errors. Moreover, the convergence rate of the estimator is improved fromOp(N-1)of the initial estimator toOp(N-3/2)for one-lag differential signal condition and fromOp(N-2)of the initial estimator toOp(N-5/2)for multilag differential signal condition, respectively, by only three iterations. The range of the lag is discussed and the optimal lag is obtained for the multilag differential signal condition when the lag is of orderN. The estimator of frequency rate with optimal lag is very close to Cramer-Rao lower bound (CRLB) as well as the asymptotic variance of least-squares estimator (LSE) at moderate signal-to-noise ratio (SNR). Finally, simulation experiments are performed to verify the effectiveness of the algorithm.
Analytic Formulation for the Sound Absorption of a Panel Absorber under the Effects of Microperforation, Air Pumping, Linear Vibration and Nonlinear Vibration
Authors: Lee Y. Y.
Published: July 2014

This study includes the first work about the absorption of a panel absorber under the effects of microperforation, air pumping, and linear and nonlinear vibrations. In practice, thin perforated panel absorber is backed by a flexible wall to enhance the acoustic performance within the room. The panel is easily excited to vibrate nonlinearly and the wall can vibrate linearly. However, the assumptions of linear panel vibration and no wall vibration are adopted in many research works. The development of the absorption formula is based on the classical approach and the electroacoustic analogy, in which the impedances of microperforation, air pumping, and linear and nonlinear vibrations are in parallel and connected to that of the air cavity in series. Unlike those finite element, numerical integration, and multiscale solution methods and so forth, the analytic formula to calculate the absorption of a panel absorber does not require heavy computation effort and is suitable for engineering calculation purpose. The theoretical result obtained from the proposed method shows reasonable agreement with that from a previous numerical integration method. It can be concluded that the overall absorption bandwidth of a panel absorber with an appropriate configuration can be optimized and widened by making use of the positive effects of microperforation, air pumping, and panel vibration.
Biotechnological Applications Derived from Microorganisms of the Atacama Desert
Authors: Azua-Bustos Armando , González-Silva Carlos
Published: July 2014

The Atacama Desert in Chile is well known for being the driest and oldest desert on Earth. For these same reasons, it is also considered a good analog model of the planet Mars. Only a few decades ago, it was thought that this was a sterile place, but in the past years fascinating adaptations have been reported in the members of the three domains of life: low water availability, high UV radiation, high salinity, and other environmental stresses. However, the biotechnological applications derived from the basic understanding and characterization of these species, with the notable exception of copper bioleaching, are still in its infancy, thus offering an immense potential for future development.