bluuebunny/crossref_metadata_2025 huggingface dataset:
Development of Integrated Experiment Program for Marine Concrete Durability
Authors: Yoon In Seok
Published: December 2013

Traditionally main driving force of chloride penetration in concrete have been regarded as a diffusion, however, large construction such as tunnel elements and foundations for bridges can be placed on large sea water depths where the water pressure is fairly different from the pressure in the splash zone. Moreover, hydrostatic pressure increases in proportional to measured depth from the surface of water because of the increasing weight of water exerting downward force from above. In this study, new experiment method to estimate chloride penetration of concrete under water pressure is introduced. The water pressure has a great influence on the chloride penetration and thereby on the service life of marine concrete.
Improvement of Acid Clay Using Calcium-Rich By-Product Recovered from Petroleum De-Sulfur Operation
Authors: Chien Chuan Chi , Chang-Chien Shui Wen , Wang Min Chao , Liao Yuan Chung , Lu Yueh Shih , Yang Tsung Yin
Published: December 2013

The objective of this research is to study the efficiency of acclimating the Tapumei Series red clay collected from Ming-Tou, Na-Tou in central Taiwan by using the calcium-rich by-product recovered from the CFB (Circulation Fluidized-Bed Boiler) de-sulfur operation. At the end of the testing period, the samples were dried, sieved and analyzed for pH, exchangeable calcium, magnesium, potassium, and sodium, and aluminum. The plant growth was observed for 7 weeks in order to investigate the influence of soil improvement on the growth and production of corn. The results reveal that all samples show an initial sharp increase from 3 to 7.5, 8.1, 8.4 and 8.6 for samples added with 18, 27, 36 and 45 tons/hectare of lime, respectively, and the final pH values after 6 months were 6.5, 7.2, 7.6 and 7.9, respectively. The lime treatment increases the soil exchangeable anion concentrations and reduces the aluminum ion concentration. This is because that the recovered CBF by-product is rich in CaO that neutralizes the soil H+ and raises the soil pH. Additionally, the anions contained in the by-product will also enhance the soil nutrients and lower the solubility of aluminum.
The Composition of Humic Acids Separated from Compost Prepared from Biologically Degradable Waste
Authors: Kucharova Jana , Raclavsky Konstantin , Kovarik Radim , Bieleszova Silvia
Published: December 2013

Humic substances (humic acids and fulvoacids) were studied in compost produced from biologically degradable waste. Pyrolytic gas chromatography with mass spectrometrical detection was used for determination of arenes (toluene, styrene, p-xylene, benzene and ethylbenzene) in the pyrolysate. An influence of composition of biologically degradable waste on humification process in composts can be evaluated from data on amount and ratios of humic acids and fulvoacids.
Numerical Simulation on Flow Field inside the Drainage Valve of the Natural Gas Pipeline
Authors: Deng Zhian , Deng Hao Yun , Xie Mei
Published: December 2013

In order to ensure safety and reliable operation of the natural gas pipeline drainage valve,the 3D numerical simulation on flow field characteristics inside the drainage valve of the natural gas pipeline under the different conditions of the seasons of winter and summer is carried out by using the standard model. In the tow different season condition, the streamline and velocity vector distribution inside the drainage valve has been studied. Under the two seasons conditions are studied. The results show that as the change of drainage valve opening the turbulence appear in the valve and the maximum value appears in the inlet,which the winter is larger than summer.The velocity vector distribution in the drainage valve is not the same and the larger velocity appears at the drain exit with the valve opening increasing. The differences in temperature, condensate discharge, condensate gas pipeline in different displacement,density and viscosity in the winter seasons and summer seasons results in the different characteristic.of the flow field characteristics inside discharging valve.
Effect of Tool Shape on Galling Behavior in Plate Shearing
Authors: Yamada Tomohiro , Wang Zhi Gang , Fukao Takuya
Published: December 2013

Finish blanking is one of the precision shearing processes and it has some features such as the formability of a high ratio of the burnished surface, lower surface expansion ratio of the burnished surface. The purpose of the present work is to clarify the effect of the tool shape in finish blanking on galling behavior. A high-tensile-strength-steel plate with a thickness of 6mm is used in the present paper. The edge shape of punch is changed while the clearance is kept to 12%t. Galling is observed except for the PW punch with the edge angle of 30 degrees at the first shearing operation. In the case of the PW punch with the edge angle of 30 degrees, galling cant be found clearly even when the shearing number increases until 20. The burnished surface has a glossy part with the clean metal for the punches except for the PW punch with the edge angle of 30 degree. It is found that the glossy part is generated after fracture occurs at the punch edge and then causes galling.
Structures Analysis and Optimum Design of the Large Stroke Two-Axis Fast Tool Servo
Authors: Wu Jia Qi , Zou Qing , Wang Tao , Zhang Qi Chao , Zhang Yong Li , Yao Jian Ning
Published: December 2013

A two degree of freedom large-stroke linear FTS device was designed in this paper, the device with flexible hinges as the guidance and support part, achieved the linear degrees of freedom in X and Z. In addition, structure design and optimizationanalysis of static characteristic and dynamic characteristicresponse surface analysis of FTS device were worked as well in this paper ,then the stiffness and strength characteristics of FTS device has been greatly improved, fully meet the design requirements, achieved the desired effect.
Study of Spindle Current Signals for Tool Breakage Detection in Milling
Authors: Lian Ling Neng , Li Bin , Liu Hong Qi
Published: December 2013

Failure of cutting tools significantly decreases machining productivity and product quality, thus, tool condition monitoring is significant in modern manufacturing processes. In this paper, a novel method based on singular value decomposition (SVD) and Linear Discriminant analysis (LDA) is proposed for detection of different broken tooth via spindle-motor current signals generated in end milling process. First, SVD algorithm is adopted to extract the useful singular values as salient features for indicating the tool state. Then classify the tool breakage event based on the selected features through the LDA technique. The experiments on a CNC Vertical Machining Centre show that this method is effective and can accurately classify the different broken tooth in end mill process.
A Study on the Applicability of Direct Evaporative Cooling Air Conditioner Used in Lanzhou
Authors: Zhang Jian , Zheng Zong Da
Published: December 2013

This paper tests a direct evaporative cooling air conditioner which used in Lanzhou, China, obtain wet and dry bulb temperature, relative humidity, and other technical parameters, analysis the performance of the units by cooling efficiency and resistance, to study if the units could be applied in Lanzhou. Lanzhou belongs to the dry areas, so direct evaporative cooling air conditioner will perform high applicability here, and contribute to energy conservation and environmental protection.
The Research of the Plane Receiving Array in Offset Parabolic Reflector Antenna with Multi-Beam at Millimeter-Wave Band
Authors: Hu Qing , Gao Rong , Chen Hui , Luo Zheng Hua
Published: December 2013

The receiving characteristics of the 90 degrees offset parabolic reflector antenna with multi-beam at millimeter-wave band are analyzed. A tentative analysis is made by using the plane receiving array instead of the traditional curved surface receiving array. The diffraction speckle on the receiving plane of the incident beam with various angles is calculated and analyzed by adopting the combination method of Ray-tracing and Stratton-Chu vector diffraction integral. The numerical results indicate that it is available by using the plane receiving array instead of the curved surface receiving array to the beam in some incident angles in the 90 degrees offset parabolic reflector antenna at millimeter-wave band.
Development of Temperature Control System of Multi-Function and All-Electric Rheometer
Authors: Li Xiang Gang , Liu Yue Jun , Liu Wen Yong , Tan Hui , Zhou Xiao Yuan , Zeng Yi
Published: December 2013

In order to study the nonlinear viscoelasticity of polymer melts at high shear rate, multi-function and all-electric rheometer (MAR) was designed by the authors. Development of temperature control system of MAR is important because rheological behavior of polymer melts is affected by temperature significantly. The design principle of the temperature control system of MAR was studied. According to the temperature upper limit the barrel need to reach, and the power the heating system can offer to maintain the temperature, the suitable type of heating system was determined. Considering the requirement of heater and the measurement error, the suitable type of temperature transducer was determined. The measured values of temperature were compared with the set values of them to evaluate the temperature control error of MAR. The results show that the temperature fluctuation is smaller than ±0.4°C in 3.5 minute. Therefore, the temperature control error of MAR is small enough for rheological test. And the temperature control stability of MAR is very well.
Research on Piano Music Signal Recognition Based on Short-Time Fourier Analysis
Authors: Chen Xu , Tang Jun
Published: December 2013

This paper starts with the basic process of music recognition to complete the study on extraction and realization of seven musical characteristics of the music features characterization, at the same time, the paper in-depth studies the pitch value duration, tonality characteristic extraction unit. Fourier analysis method based on short-time uses the computer programming for audio signal automatic analysis and processing, implements the characteristics recognition of the piano music playing, Experimental data show that the average recognition rate of algorithm is above 95% with the strong recognition ability, which provides the core technology support for developing the evaluation system of piano performance.
Investigation on Soldering High Volume Fraction SiC Particle Reinforced Aluminum Metal Matrix Composites
Authors: Wang Peng , Li Qiang , Niu Ji Tai
Published: December 2013

In order to improve the poor wettability of SiCp/Al composites, surface modification by copper brush plating and an active Al-base solder containing Cu, Mg and Sn were investigated in this paper. After vacuum brazing, a good soldered joint with high shearing strength of 145.6MPa was succesfully frabricated at 580°C, holding time of 30min. The microstructure of soldered joints was studied by SEM and EDS. The results show that the Cu-plating , as a bridge, could obviously enhance the reaction between the molten solder and composites, the fractography revealed the fracture occurs within the composite, indicating a good adhesion between the solder alloy and the SiCp/Al composites.
Research on Tensile Bearing Capacity of Self-Drilling Screw Joints for Thick Faced Roof Sandwich Panels
Authors: Zha Xiao Xiong , Tang Zhi Rong
Published: December 2013

To find out the connection of screw joints and base materials or the metal crest surface at the head of screw which is destroyed first, the tensile bearing capacity of joints between self-drilling screws (SDS) and the base materials were tested first. With two types of SDS joints furnished with C-saddle washers (C-SW) and M-saddle washers (M-SW) respectively, test and analysis on the tensile bearing capacity of SDS joints were undertaken. Corresponding finite element (FE) models were analyzed by ANSYS/LS-DYNA software. Based on mechanical analysis, a new theoretically computational formula for tensile bearing capacity of SDS joints is proposed.
Study on the Static and Dynamic Load Test of Skew Bridge
Authors: Han Hai Bo , Wang Lei , Li Zhuang , Long Xing Hang
Published: December 2013

The longitudinal axis of the bridge is not perpendicular to the flow of the river and the road, skew bridges are usually used, whats more, the Stress is very complicated. Through a skew bridge static and dynamic load test, the bridges stress was analyzed, in the same way, deflection and dynamic characteristics could be analyzed. The most important was the safety performance of the bridge could be evaluated.
Study on Hydraulic Characteristics of Opposite Folded Plate Reactor
Authors: Tao Pei , Song Tie Hong , Zhang Fang
Published: December 2013

By using Chlorides (Cl-) as the tracer, the residence time distribution (RTD) method was applied to study the hydraulic characteristic influences of hydraulic retention time (HRT) on the opposite folded plate reactor and the plate baffle reactor under the condition of steady operation of both clear and sludge water. Under the condition of the same HRT, dead zone of opposite folded plate reactor was less than the one of flat plate reactor.
Plastic Analysis on Buckling Restrained Braced Steel Frame
Authors: Zou Xue , Zhao Jun , Bao En He , Chen Yi Hu
Published: December 2013

Six pieces of building models were designed for studying the multilayer buckling restrained braced steel frame in this paper. The main parameter in the study included the frame strength and the level Participation ratio β. Second-order nonlinear time history analyses for models are conducted based on plastic hinge theory. The parametric analysis was performed on story displacement and shear. The results revealed that story bending deformation become more remarkable when the frame strength is increasing from 0.3 to 0.5 or the level Participation ratio β from 30% to 90%, and this situation is more obvious on the upper layer. The share of shear by the buckling restrained brace and the largest story shear ratio get larger in these models as the frame strength and the level Participation ratio β increasing.
Structural Modal Parameter Identification Based on Natural Excitation Technique
Authors: Pei Qiang , Li Long
Published: December 2013

Natural excitation technique has found an increasingly wide utilization in civil engineering field. Modal parameter identification in time domain method can identify the structural parameters in the use of impulse response data as input data. The theory of NExT method is presented. By constructing a numerical simulation example under white-noise excitation, and calculating the data by NExT method, the modal parameters can be identified according to complex exponential method and time series-method in time domain. The results and analysis indicate the validity of the method and provide a reference for engineering practice.
Modal Analysis on Steel Frame-Energy Dissipation Support Structure
Authors: Dong Shuo , Huang Cheng Wei , Shen Cheng
Published: December 2013

The energy dissipation device is put on the support bar of the steel frame structure so as to form the energy dissipation support. The structural performance can be adjusted and improved through the additional stiffness and damping so as to realize the structural damping result. As there are many elements that can affect the structural earthquake anti-seismic performance, modal analysis which is taken as the basic contents, is conducted on the application of the common support and steel frame structure of energy dissipation support and the analysis is also conducted on the influences of energy dissipation to the vibration and cycle of the steel frame so as to lay a good foundation for the analysis on the anti-seismic performance of steel frame-energy dissipation support structural system.
Numerical Study of Vertical Axis Wind Turbine Rotor Configuration
Authors: Mei Yi , Qu Jian Jun , Liu Xiao Ya
Published: December 2013

This paper presents a numerical study of a vertical axis wind rotor configuration. Below constant wind condition 8m/s, rotor power performance was investigated over variable turbine configurations. Illustrated by the simulation, increasing rotor cord to radius ratio or blade numbers will enhance the generation of vortexes and flow separation on blades, leading to the significant degradation of turbine performance. It can be conclude form the numerical analysis, a vertical axis wind turbine with high height to radius ratio applied in urban areas experienced better performance when operating in optimal tip speed ratio, with rotor cord to radius ratio between 0.2 and 0.4 and blade number of 3 or 4.
Experimental Study on the Solidification of MSWI Fly Ash
Authors: Yang Fu Yun
Published: December 2013

This paper studied the characteristics of MSWI fly ash. Using cement and lime as a binder for the fly ash treatment effect has carried out in the experimental research. This study analyzed the fly ash solidification process and the best process parameters by using cement and lime and discussed the binder curing fly ash and its mechanism in the fly ash behavior. This paper provides a valuable reference for the further study on the harmless treatment of MSWI fly ash.
The Influencing Research for Acid Pollution to Laterite Intensity
Authors: Jin Ke Sheng , Huang Ying , Chen Xiao Na
Published: December 2013

The research purpose is the change for acid pollution lateritic shearing strength indices and compressor characteristics indicial under different concentration of hydrochloric acid , differ curing time in text.The test result proven,acid pollution lateritic shearing strength indices and compressor characteristics indices population take on depress tide in company with hydrochloric acid concentration and curing horary Increase.
Research of Real Estate Appraisal Based on GIS Technology
Authors: Yang Jian Ping , Bai Qing
Published: December 2013

With the continuous development of the real estate industry, the real estate valuation business volume increasing coverage, valuation of more extensive, therefore it has become increasingly difficult. This article mainly from the characteristics of the real estate valuation and the existing problems, study of the geographic information system (GIS) is applied to real estate evaluation system of the necessity and feasibility, and puts forward the main function of the GIS system of real estate appraisal module.
Calculation Methods of CFRP Tendons Stress in Two-Span Prestressed Continuous Beams
Authors: Bai Chong Xi , Shao Xin Yan , Wang Qiu Ping
Published: December 2013

Crack width, deflection and load bearing capacity of two-span concrete continuous beams partially prestressed with unbonded carbon fiber reinforced polymer (CFRP) tendons can be calculated accurately, the first premise is to calculate reasonably the stress increment of CFRP tendons. However, the law of stress increment of unbonded tendons is unclear. Moment-curvature analysis method and deformation compatibility condition were used to compile nonlinear full-range analysis programs of this kind of continuous beam. The comparison between simulated results and tested results of stress in CFRP tendons indicates that the simulation analysis programs are reliable.
Seismic Performance of Reinforced Concrete Rectangular Hollow Bridge Piers
Authors: Zhao Yan , Jiang Hong Yu , Gu Jie , Wang Ru Qin
Published: December 2013

Hollow rectangular reinforced concrete piers have been widely used in tall-column and long-span bridges. Two large-scale experimental models of the hollow reinforced concrete bridge piers were built to study the seismic performance of the piers subjected to biaxial bending under constant axial load. The objective is to evaluate seismic performances of the model piers and the factors affecting the seismic performance of the model piers by comparing their failure mechanism, bearing capacity, ductility, energy dissipation capacity, etc. The results show that the hollow rectangular specimen experienced flexural failure with plastic hinges formed at the bottom of the piers when subjected to combined axial load and biaxial bending. The bearing capacity of the specimen increases greatly and the ductility decrease insignificantly as the axial compression ratio increases from 0.1 to 0.2, while the energy dissipation capacity is increased by 121.8%, however, the absolute value of total cumulative hysteretic energy is not magnificent.
Gap Junction Intercellular Communications Regulate NK Cell Activation and Modulate NK Cytotoxic Capacity
Authors: Tittarelli Andrés , Mendoza-Naranjo Ariadna , Farías Marcela , Guerrero Israel , Ihara Fumitaka , Wennerberg Erik , Riquelme Sebastian , Gleisner Alejandra , Kalergis Alexis , Lundqvist Andreas , López Mercedes N. , Chambers Benedict J. , Salazar-Onfray Flavio
Published: December 2013

Gap junctions (GJs) mediate intercellular communication between adjacent cells. Previously, we showed that connexin 43 (Cx43), the main GJ protein in the immune system, mediates Ag transfer between human dendritic cells (DCs) and is recruited to the immunological synapse during T cell priming. This crosstalk contributed to T cell activation, intracellular Ca2+ responses, and cytokine release. However, the role of GJs in NK cell activation by DCs and NK cell–mediated cytotoxicity against tumor cells remains unknown. In this study, we found polarization of Cx43 at the NK/DC and NK/tumor cell-contact sites, accompanied by the formation of functional GJs between NK/DCs and NK/tumor cells, respectively. Cx43–GJ-mediated intercellular communication (GJIC) between human NK and DCs was bidirectional. Blockage of Cx43-GJIC inhibited NK cell activation, though it affected neither the phenotype nor the function of DCs. Cx43 knockdown or inhibition using mimetic peptides greatly reduced CD69 and CD25 expression and IFN-γ release by DC-stimulated NK cells. Moreover, blocking Cx43 strongly inhibited the NK cell–mediated tumor cell lysis associated with inhibition of granzyme B activity and Ca2+ influx. Our data identify a novel and active role for Cx43-GJIC in human NK cell activation and antitumor effector functions that may be important for the design of new immune therapeutic strategies.
B Cell–Specific Loss of Lyn Kinase Leads to Autoimmunity
Authors: Lamagna Chrystelle , Hu Yongmei , DeFranco Anthony L. , Lowell Clifford A.
Published: December 2013

The Lyn tyrosine kinase regulates inhibitory signaling in B and myeloid cells: loss of Lyn results in a lupus-like autoimmune disease with hyperactive B cells and myeloproliferation. We have characterized the relative contribution of Lyn-regulated signaling pathways in B cells specifically to the development of autoimmunity by crossing the novel lynflox/flox animals with mice carrying the Cre recombinase under the control of the Cd79a promoter, resulting in deletion of Lyn in B cells. The specific deletion of Lyn in B cells is sufficient for the development of immune complex–mediated glomerulonephritis. The B cell–specific Lyn-deficient mice have no defects in early bone marrow B cell development but have reduced numbers of mature B cells with poor germinal centers, as well as increased numbers of plasma and B1a cells, similar to the lyn−/− animals. Within 8 mo of life, B cell–specific Lyn mutant mice develop high titers of IgG anti–Smith Ag ribonucleoprotein and anti-dsDNA autoantibodies, which deposit in their kidneys, resulting in glomerulonephritis. B cell–specific Lyn mutant mice also develop myeloproliferation, similar to the lyn−/− animals. The additional deletion of MyD88 in B cells, achieved by crossing lynflox/floxCd79a-cre mice with myd88flox/flox animals, reversed the autoimmune phenotype observed in B cell–specific Lyn-deficient mice by blocking production of class-switched pathogenic IgG autoantibodies. Our results demonstrate that B cell–intrinsic Lyn-dependent signaling pathways regulate B cell homeostasis and activation, which in concert with B cell–specific MyD88 signaling pathways can drive the development of autoimmune disease.
Nanoparticle Adjuvant Sensing by TLR7 Enhances CD8+ T Cell–Mediated Protection from Listeria Monocytogenes Infection
Authors: Lebel Marie-Ève , Daudelin Jean-François , Chartrand Karine , Tarrab Esther , Kalinke Ulrich , Savard Pierre , Labrecque Nathalie , Leclerc Denis , Lamarre Alain
Published: December 2013

Developing new adjuvants and vaccination strategies is of paramount importance to successfully fight against many life-threatening infectious diseases and cancer. Very few adjuvants are currently authorized for human use, and these mainly stimulate a humoral response. However, specific Abs are not sufficient to confer protection against persisting infections or cancer. Therefore, development of adjuvants and immunomodulators able to enhance cell-mediated immune responses represents a major medical need. We recently showed that papaya mosaic virus nanoparticles (PapMV), self-assembled from the coat protein of a plant virus and a noncoding ssRNA molecule, are highly immunogenic in mice. PapMV can be used either as a vaccine delivery platform, through fusion of various epitopes to the coat protein or as adjuvant to enhance humoral immune responses against coadministered Ags or vaccines. However, the mechanisms that confer these immunomodulatory properties to PapMV and its ability to enhance T cell vaccines remain unknown. Using immunization studies in mice, we demonstrate in this paper that PapMV represents a novel TLR7 agonist with strong immunostimulatory properties. More importantly, pretreatment with PapMV significantly improves effector and memory CD8+ T cell responses generated through dendritic cell vaccination increasing protection against a Listeria monocytogenes challenge.
On the role of kinetic and interfacial anisotropy in the crystal growth theory
Authors: Giga Mi-Ho , Giga Yoshikazu
Published: December 2013

A planar anisotropic curvature flow equation with constant driving force term is considered when the interfacial energy is crystalline. The driving force term is given so that a closed convex set grows if it is sufficiently large. If initial shape is convex, it is shown that a flat part called a facet (with admissible orientation) is instantaneously formed. Moreover, if the initial shape is convex and slightly bigger than the critical size, the shape becomes fully faceted in a finite time provided that the Frank diagram of interfacial energy density is a regular polygon centered at the origin. The proofs of these statements are based on approximation by crystalline algorithm whose foundation was established a decade ago. Our results indicate that the anisotropy of interfacial energy plays a key role when crystal is small in the theory of crystal growth. In particular, our theorems explain a reason why snow crystal forms a hexagonal prism when it is very small.
Systematic Review of the Effects of Exercise on Activities of Daily Living in People With Alzheimer’s Disease
Authors: Rao Ashwini K. , Chou Aileen , Bursley Brett , Smulofsky Jaclyn , Jezequel Joel
Published: December 2013

OBJECTIVE. Alzheimer’s disease (AD) results in a loss of independence in activities of daily living (ADLs), which in turn affects the quality of life of affected people and places a burden on caretakers. Limited research has examined the influence of physical training (aerobic, balance, and strength training) on ADL performance of people with AD.

METHOD. Six randomized controlled trials (total of 446 participants) fit the inclusion criteria. For each study, we calculated effect sizes for primary and secondary outcomes.

RESULTS. Average effect size (95% confidence interval) for exercise on the primary outcome (ADL performance) was 0.80 (p < .001). Exercise had a moderate impact on the secondary outcome of physical function (effect size = 0.53, p = .004).

CONCLUSION. Occupational therapy intervention that includes aerobic and strengthening exercises may help improve independence in ADLs and improve physical performance in people with AD. Additional research is needed to identify specific components of intervention and optimal dosage to develop clinical guidelines.
Valuation of Mudflats in Nature-Based Tourism: Inclusion of Perceived Value of Festival Experiences
Authors: Choi Youngjoon , Lee Won Seok , Lee Choong-Ki , Dattilo John
Published: December 2013

As a particular type of wetlands, mudflats are a potentially valuable natural resource that has become an alternative destination for nature-based tourism. One prominent example of using mudflats in a tourism context is the Boryeong Mud Festival. To understand the role of the touristic experience in shaping the need for preservation, this study: (a) examines the effect of experiences in a nature-based festival on visitors' willingness-to-pay (WTP) to preserve mudflats; and (b) estimates the preservation value of mudflats by using a contingent evaluation method. In particular, the perceived value of festival experiences is included in the proposed models when estimating visitors' WTP. The results indicate that the experience of festival visitors was positively associated with WTP by showing that festival visitors perceived a higher level of utility for preserving mudflats as the functional value of festival experience increased. Based on the error-reduced WTP results, the average respondents' WTP and the annual aggregate preservation value of mudflats were estimated at KRW 11,039 (US$8.64) and KRW 22,818 million (US$17.85 million), respectively.
Humanized Culture of Periosteal Progenitors in Allogeneic Serum Enhances Osteogenic Differentiation and In Vivo Bone Formation
Authors: Roberts Scott J. , Owen Helen C. , Tam Wai Long , Solie Lien , Van Cromphaut Sophie J. , Van den Berghe Greet , Luyten Frank P.
Published: December 2013

The translation of stem cell-based regenerative solutions from the laboratory to the clinic is often hindered by the culture conditions used to expand cell populations. Although fetal bovine serum (FBS) is widely used, regulatory bodies and safety concerns encourage alternative, xeno-free culturing practices. In an attempt to apply this approach to a bone-forming combination product of human periosteal progenitors (human periosteum derived cells) on a clinically used calcium phosphate carrier, FBS was substituted for human allogeneic serum (hAS) during cell expansion. It was found that cell proliferation was increased in hAS along with an apparent commitment to the osteogenic lineage, indicated by enhanced Runx2 expression, as well as alkaline phosphatase activity and matrix mineralization. Following analysis of signaling pathways, it was found that interferon-mediated signaling was downregulated, whereas JAK-STAT signaling was upregulated. STAT3 phosphorylation was enhanced in hAS-cultured human periosteum derived cells, inhibition of which ablated the proliferative effect of hAS. Furthermore, following in vivo implantation of hAS-cultured cells on NuOss scaffolds, enhanced bone formation was observed compared with FBS (71% increase, p < .001). Interestingly, the de novo-formed bone appeared to have a higher ratio of immature regions to mature regions, indicating that after 8 weeks implantation, tissue-formation processes were continuing. Integration of the implant with the environment appeared to be altered, with a decrease in calcium phosphate grain size and surface area, indicative of accelerated resorption. This study highlights the advantages of using humanized culture conditions for the expansion of human periosteal progenitors intended for bone regeneration.
Identification of Novel Human Leukocyte Antigen-A*0201-Restricted, Cytotoxic T Lymphocyte Epitopes on CD133 for Cancer Stem Cell Immunotherapy
Authors: Ji Jianfei , Judkowski Valeria A. , Liu Gentao , Wang Hongqiang , Bunying Alcinette , Li Zhenhua , Xu Minlin , Bender James , Pinilla Clemencia , Yu John S.
Published: December 2013

Targeting cancer stem cells (CSCs) with immunotherapy may be an effective means to prevent recurrences in glioblastoma multiforme (GBM). It is well established that CD133 is expressed in the population of GBM tumor cells representing CSCs. This raises a possibility that CD133 could serve as a potential target for cytotoxic T cells (CTLs) to target glioblastoma cancer stem cells. Two potential human leukocyte antigen (HLA)-A*0201-restricted CD133 epitopes, ILSAFSVYV (CD133-405) and YLQWIEFSI (CD133-753), showed strong binding to HLA-A*0201 molecules. In vitro immunogenicity studies generated peptide-specific CD8+ CTLs from normal donors. Autologous monocyte-derived dendritic cells pulsed with the CD133-405 or CD133-753 peptides generated CTLs that efficiently recognized the CD133 epitopes presented in T2 HLA-A*0201 cells and specifically lysed CD133+ HLA-A*0201+ GBM CSCs. These studies demonstrated natural processing and subsequent presentation of these epitopes in GBM CSCs and the ability of CTLs to kill CSCs bearing the antigen. Immunization studies in mice using the mouse homolog CD133 epitopes demonstrated immunogenicity in the absence of autoimmune damage. The results presented in this study support the use of CD133-specific epitope vaccines to target CSCs in glioblastoma and other cancers.
Accurate Prediction of Drug-Induced Liver Injury Using Stem Cell-Derived Populations
Authors: Szkolnicka Dagmara , Farnworth Sarah L. , Lucendo-Villarin Baltasar , Storck Christopher , Zhou Wenli , Iredale John P. , Flint Oliver , Hay David C.
Published: December 2013

Despite major progress in the knowledge and management of human liver injury, there are millions of people suffering from chronic liver disease. Currently, the only cure for end-stage liver disease is orthotopic liver transplantation; however, this approach is severely limited by organ donation. Alternative approaches to restoring liver function have therefore been pursued, including the use of somatic and stem cell populations. Although such approaches are essential in developing scalable treatments, there is also an imperative to develop predictive human systems that more effectively study and/or prevent the onset of liver disease and decompensated organ function. We used a renewable human stem cell resource, from defined genetic backgrounds, and drove them through developmental intermediates to yield highly active, drug-inducible, and predictive human hepatocyte populations. Most importantly, stem cell-derived hepatocytes displayed equivalence to primary adult hepatocytes, following incubation with known hepatotoxins. In summary, we have developed a serum-free, scalable, and shippable cell-based model that faithfully predicts the potential for human liver injury. Such a resource has direct application in human modeling and, in the future, could play an important role in developing renewable cell-based therapies.
Influence of In Vitro and In Vivo Oxygen Modulation on β Cell Differentiation From Human Embryonic Stem Cells
Authors: Cechin Sirlene , Álvarez-Cubela Silvia , Giraldo Jaime A. , Molano Ruth D. , Villate Susana , Ricordi Camillo , Pileggi Antonello , Inverardi Luca , Fraker Christopher A. , Domínguez-Bendala Juan
Published: December 2013

The possibility of using human embryonic stem (hES) cell-derived β cells as an alternative to cadaveric islets for the treatment of type 1 diabetes is now widely acknowledged. However, current differentiation methods consistently fail to generate meaningful numbers of mature, functional β cells. In order to address this issue, we set out to explore the role of oxygen modulation in the maturation of pancreatic progenitor (PP) cells differentiated from hES cells. We have previously determined that oxygenation is a powerful driver of murine PP differentiation along the endocrine lineage of the pancreas. We hypothesized that targeting physiological oxygen partial pressure (pO2) levels seen in mature islets would help the differentiation of PP cells along the β-cell lineage. This hypothesis was tested both in vivo (by exposing PP-transplanted immunodeficient mice to a daily hyperbaric oxygen regimen) and in vitro (by allowing PP cells to mature in a perfluorocarbon-based culture device designed to carefully adjust pO2 to a desired range). Our results show that oxygen modulation does indeed contribute to enhanced maturation of PP cells, as evidenced by improved engraftment, segregation of α and β cells, body weight maintenance, and rate of diabetes reversal in vivo, and by elevated expression of pancreatic endocrine makers, β-cell differentiation yield, and insulin production in vitro. Our studies confirm the importance of oxygen modulation as a key variable to consider in the design of β-cell differentiation protocols and open the door to future strategies for the transplantation of fully mature β cells.
A cost-minimization analysis of combination therapy in hypertension: fixed-dose vs extemporary combinations
Authors: Bellone Marco , Sbarra Pierluigi
Published: December 2013

BACKGROUND: Cardiovascular disease management and prevention represent the leading cost driver in Italian healthcare expenditure. In order to reach the target blood pressure, a large majority of patients require simultaneous administration of multiple antihypertensive agents.OBJECTIVE: To assess the economic impact of the use of fixed dose combinations of antihypertensive agents, compared to the extemporary combination of the same principles.METHODS: A cost minimization analysis was conducted to determine the pharmaceutical daily cost of five fixed dose combinations (olmesartan 20 mg + amlodipine 5 mg, perindopril 5 mg + amlodipine 5 mg, enalapril 20 mg + lercanidipine 10 mg, felodipine 5 mg + ramipril 5 mg, and delapril 30 mg + manidipine 10 mg) compared with extemporary combination of the same principles in the perspective of the Italian NHS. Daily acquisition costs are estimated based on current Italian prices and tariffs.RESULTS: In three cases the use of fixed‑dose combination instead of extemporary combination induces a lower daily cost. Fixed combination treatment with delapril 30 mg + manidipine 10 mg induces greater cost savings for the National Health System (95,47 €/pts/year), as compared to free drugs combination therapy.CONCLUSIONS: Compared with free drug combinations, fixed‑dose combinations of antihypertensive agents are associated with lower daily National Health Service acquisition costs.
Teaching Nonlinear Dynamics at the Freshman Level
Authors: Chen Li-Qun
Published: December 2013

A course on nonlinear dynamics is taught for freshmen in Shanghai University. Focusing on the scientific concepts of chaos, fractals and bifurcation, the course helps students to understand diversity, uncertainty and unpredictability in the real world. The paper surveys the technical contents of the course and highlights its pedagogical features. Student feedback is also reported.
Incorporating Research into a First-Year Fluid Mechanics Class
Authors: Su Tsung-Chow
Published: December 2013

Through simple flow visualization experiments, it is possible to introduce students to research in fluid mechanics during their first fluid mechanics course. Our visual sense is so powerful that in an instant we can often grasp both the big picture and the detail. To quote Richard Feynman, considered to be one of the top scientists of the 20th century, ‘fundamental questions can be easily answered just by looking at the thing‘. One should know, however, precisely how to look, analyze and investigate visually. Interesting small-scale fluid motion may be observed and photographed to reveal fundamental processes in an inexpensive and team-building manner that builds confidence, gives students skills for lifelong learning, and prepares them for graduate research. This paper presents our students' experience.
The Holding of Contests in Engineering Mechanics
Authors: Shimanovsky Alexandr O.
Published: December 2013

The Belarusian State University of Transport runs three contests in engineering mechanics for students: a theory contest (individual and team events), a ‘brain ring’ team contest and a computer team contest. Problem selection for these contests is described in this paper, along the organizational aspects are considered, along with the approach to the checking of solutions. Some examples of problems are presented, including some which have caused difficulties for the participations.
Weighting Function Selection Problem in the Galerkin Method
Authors: Salonen E.-M. , Kouhia R. , Holopainen R.
Published: December 2013

When a problem contains more than one unknown function and a corresponding number of differential equations, the contents of the Galerkin method are not necessarily completely clear. This theme is discussed in the paper by considering four example cases: one-dimensional heat conduction, the bending of an Euler–Bernoulli beam, a regenerator problem and an axially moving string problem. A strategy for selection of the proper weighting function is proposed. Some numerical results are presented. Suggestions regarding how a basic finite element course for engineering students might proceed in its initial stages are given.
A Conceptual Model for Understanding Convective Heat Transfer
Authors: Wolfe A. K. , Nieh S.
Published: December 2013

The purpose of this paper is to present a conceptual model (boxcar model) for teaching and explaining convective heat transfer, and to present three engineering examples of where and how the model can be used. One application for the model would be to explain the fundamentals of convective heat transfer. Another would be to explain and resolve heating, ventilation and air-conditioning problems. The boxcar model provides the engineer with a visualization of simple to complex engineering applications as well as a method for enhancing the teaching to mechanical engineering students of topics involving convective heat transfer and heat exchangers.
Confirmation of Intuitions about the Behavior of Beams and Trusses
Authors: Dym Clive L. , Williams Harry E.
Published: December 2013

This note briefly explores two well known mechanics models, elementary beams and trusses, with the aim of illustrating widely acknowledged intuitions about their behavior. It will be explicitly shown how a discrete distribution of forces can be developed into a uniform load. Similarly, a simple truss will be examined to explicitly demonstrate its behavior as an archetypal beam. Thus, two instances of mechanics intuition that are well known, but for which actual demonstrations do not appear in the literature, are confirmed.
A Boiling Heat Transfer Experiment for a Senior-Level Engineering Laboratory
Authors: Chase Nathan , Choi Brian , Carrica Pablo M.
Published: December 2013

This paper presents a simple experiment that can be executed in an undergraduate laboratory to observe the boiling curve, including the transition and film boiling regimes. The experiment involves submerging an instrumented copper sphere into liquid nitrogen and measuring the evolution of the temperature of the sphere. Besides providing excellent visualization of the film, transition and nucleate boiling regimes, from the measurements the boiling curve can be obtained. Quantitative results and uncertainty analysis are presented for the critical heat flux and minimum heat flux. A paradox is presented when insulation is added to the sphere, since it can prevent the creation of a vapor film, maintaining the more efficient transition and nucleate boiling heat transfer regime and thus cooling the copper sphere faster than with no insulation. As expected, when the copper sphere is insulated further, heat transfer diminishes, offsetting the gains made by maintaining nucleate heat transfer. The experiment also evaluates temperature gradients inside the sphere and the validity of the assumption of uniform sphere temperature. This experiment is suitable for a senior-level experimental class or as a part of a heat transfer course.
Engineering Education in the Internet Age: Contrasting Faculty Adoption
Authors: Lehman Alexander , Kohl James G.
Published: December 2013

This study examines internet usage in undergraduate mechanical engineering courses in a small private university in California, with the goal of establishing best practices for faculty implementation of online content. To do this, six mechanical engineering faculty were interviewed regarding their use of internet resources in their various courses, and their views on how successful or unsuccessful they were in using the internet to improve their pedagogy. A survey was then administered to junior and senior mechanical engineering students to identify their needs and to triangulate the interview findings. It was found that faculty can be grouped into three general archetypes based on their use of online resources in each of their courses: internet resisters, internet users, and internet adopters. It was also found that while professors would invariably teach each individual course as a single archetype, most would teach different courses as different archetypes, to best fit each course's requirements and content. Strengths and weaknesses of each archetype are identified, and a continuing dialog between engineering faculty and students is recommended to determine what practices will best fit the needs of the internet-savvy student population within each course.
Integrating Simulation into the Engineering Curriculum: A Case Study
Authors: Ray Baidurja , Bhaskaran Rajesh
Published: December 2013

In this paper, we describe improved strategies for teaching computational fluid dynamics (CFD) using the commercial software ANSYS Fluent to upper-level undergraduates and graduate students. We consider a case study from an upper-level elective fluid dynamics course and evaluate various out-of-class learning materials and in-class active learning techniques. We show that, in agreement with previous research, most student learning happens out of class. We show a direct correlation between the materials developed in a reference hand-out and the students' expertise in the area. We introduced i-clickers as a means of promoting active learning in the classroom to emphasize the ‘expert approach’ in simulation. Their use received a mixed response from the students and we discuss the reasons and a possible remedy. We demonstrate that carefully designed out-of-class learning materials are crucial to students' learning of CFD, and that i-clickers have to be used with care if they are to be effective in engaging students during the lectures. All of these findings inform not only future renditions of this course, but also instruction of CFD in general.