bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on Hazards Identification for the Life Cycle of Household Electric Blankets
Authors: Liu Xia , Luo Hong Qi , Fu Rui , Song He Liang
Published: June 2014

Household electric blankets are widely used in China, but the problem of quality and safety is also more prominent, which is a serious threat to the health and safety of consumers. The structure characteristics and working principle of household electric blanket are analyzed. The hazards in the each stage of full life cycle are identified, including the stages of designing, manufacturing, packaging, transporting, utilizing and recycling. Hazard identification of each stage is made with methods of scenario analysis, safety check list, fault hypothesis analysis, hazard and operability analysis, failure mode and effect analysis and fault tree analysis, respectively.
Analytical Modeling and Numerical Simulations on the Scaling of Biomicrofluidic Droplets
Authors: He Pei Yuan , Zhang Li Guo
Published: June 2014

Biomicrofluidic silhouettes brought about scientific challenges merited to be investigated through explicit florescence observation, implicit physical-chemical analysis and intermediate conductive level manipulation. Droplet generation, as the typical biomicrofluidic phenomenon, is a complicated dynamic process. In this work, we established both linear and non-linear models to describe the biomicrofluidic droplet variation through applied mathematical techniques, in order to find the corresponding summarizations. Model analysis showed that non-linear models presented ameliorated descriptive capacity.
Design of a Manageable P2P VoD System
Authors: Duan Ming Yi , Yang Ya Jun , Huang Ji Hai
Published: June 2014

For the lack of management mechanism in P2P VoD system, this paper presents design of a manageable P2P VoD system, describes the system architecture and design of each module, and been tested on CERNET2. By using intelligence node management, it has resolved the inefficient management problem of traditional P2P distribution system.
Dynamic Characteristics of Hybrid Girder Cable-Stayed Bridge
Authors: Lv Hua Gang , Lv Xue Ying , Shen Yong Gang , Qian Kai Jun
Published: June 2014

This paper is made after the dynamic test on Jing hang Channel Bridge in Wujiang, Jiangsu Province. Based on the test on this bridge, we get dynamic characteristics of the bridge span structure. We will analysis the vibration generated from the steel and concrete box girders of the bridge while the car is running on it. Based on the different characteristics of vibration from the two kinds of girders, we can analysis the influence of this hybrid girder on driving comfort.
Risk Analysis of Quality and Safety for Laser Pointer with Remote Control
Authors: Liu Xia , Lei Ming , Liu Hu Wei , Cao Yin , Gao Xiao Hong
Published: June 2014

Multimedia teaching and lecturing have been widely used nowadays, and then the technology of laser pointer with remote control appears in order to satisfy the requirements. The radiation power of some laser pointers is large, which may be lead to impaired eyes due to improper use. The hazard of laser radiation was analyzed. The standards, laws and regulations of the domestic and foreign were compared. Some suggestions and measures of perfecting the relative standards, strengthening consumers' education and industry rectification were provided.
Effect of Carbon Source on the Particles Morphology and Carbon Structure of LiFePO4/C Composites
Authors: He Ji Chuan
Published: June 2014

The LiFePO4/C cathode materials were successfully synthesized by solid state method with glucose, sucrose, citric acid, PEG-4000, starch and adlipic acid as carbon sources. The microstructure and morphology of LiFePO4/C composites were characterized by X-ray diffraction, Raman spectroscopy and scanning electron microscopy. The results showed that the carbon source is an important affecting factor for controlling the morphology and size of LiFePO4/C composites and carbon coating layers structure. The carbon coating layers synthesized with glucose and sucrose as carbon sources possess smaller ID/IG ratio demonstrating that carbon coating layers contain higher grapheme carbon. The particles of LiFePO4/C composites synthesized with glucose, PEG-4000 and starch as carbon sources have high dispersibility, good particles size distribution and near-spherical morphology.
Synthesis and Pseudocapacitve Properties of Tungsten Oxide Nanorods
Authors: Zou Ben Xue , Wang Yan , Huang Fang
Published: June 2014

Tungsten oxide (WO3) nanorods were fabricated and evaluated as negative electrode materials for supercapacitors. The influence of the concentration of sodium chloride and pH value of the synthesis solution were investigated. The pH value of solution and sodium chloride play important roles in the formation of uniform dispersed nanorods of WO3. Cyclic voltammetry and chronopotentiometry results show that nanorods WO3 film exhibit advanced pseudocapacitive performance over a negative potential range of − 0.6 V to 0.2 V vs. SCE in 1M H2SO4 with the high specific capacitance of 114 F g-1, compared to that of the bulk WO3 electrode materials.
Preparation and Performance of CGFS Reinforced PVA/RSP Composite
Authors: Wu Chuan Bao , Li Xian Zhi
Published: June 2014

Application of chopped glass fiber strand (CGFS) in rice straw based composite was studied and the reinforcing effect of CGFS was evaluated. Rice straw powder (RSP) was used as main material and poly (vinyl alcohol) (PVA) was selected as adhesive agent. Composites were prepared by hot-pressing method at 10 MPa pressure, 140 °C for 10 min, with the mass ratio of RSP to PVA of 4:3. Results showed that the tensile strength of the composites first increased and then decreased with increasing CGFS amount. When the mass ratio of CGFS to RSP was 7:15, the composite reached its maximum strength of 20.47 MPa. CGFS showed obvious reinforcing effect. Strength at tensile break showed similar change law and tensile strength equaled to or was slightly higher than the strength at tensile break. The tensile elongations of all composites with CGFS were higher than 20%, proving the toughening role of CGFS. The hardness of composites showed certain non-uniformity and lay between 87 and 96. Negligible difference existed in every composite.
Molecular Structure and the Removal Effect of COS over Iron Carbonyls: Fe2(CO)9
Authors: Guo Hui Bin , Tang Li Hong , Li Kai , Ning Ping , Guan Qing Qing , Gu Jun Jie , Sun Xin , Liu Gui , Li Shan , Duan Zheng Yang
Published: June 2014

Transition metal carbonyls are novel catalysts.This study examined the removal effect of COS over Fe2(CO)9 at atmosphere pressure compared with the removal of CS2 over Fe2(CO)9 at atmosphere pressure.By experiment contrast analysis,the removal effect of COS better than the removal effect of CS2. It shows that the existence of CO without producing competition.The removal effect of COS basically maintain the level of 60%~80% is good at atmosphere pressure.Then analyzing of Reaction mechanism, there are three kinds the interaction between Fe2(CO)9 and COS at atmosphere pressure are listed.There is every reason to believe that Fe2(CO)9 can make COS activation.
Electroless Deposition of Nickel Nanoparticles at Room Temperature
Authors: Balela Mary Donnabelle , Yagi Shunsuke , Matsubara Eiichiro
Published: June 2014

Metallic nickel (Ni) nanoparticles with a mean diameter of about 70 nm are successfully formed by electroless deposition in an aqueous solution at 273 K. The formation of Ni nanoparticles is investigated by in situ mixed potential measurement in combination with thermodynamic calculation. The deposition rate of Ni is measured using an electrochemical quartz crystal microbalance (EQCM). The mixed potential of reaction solution drastically decreases below the oxidation-reduction potential of Ni (II)/Ni redox pair at about-0.60 v vs SHE after 30 min reaction. This coincides with a sharp increase in the deposited mass, suggesting Ni deposition.
Cysteine Conjugated Gold Nanoparticles and their Scavenging Free Radicals Properties
Authors: Chou Chih Wei , Yang Jen Ming , Yang Tsung Shi , Shih Yang Chia , Hsieh Hui Hsuan , Chang Ko Hsin , Chen Ko Shao , Tzu Wu Lii , Hseu You Cheng , Wei Yi Syuan
Published: June 2014

This study deals with cysteine on gold (Au) nanoparticles which prepared by sodium citrate reduction. The effects of cysteine conjugated Au nanoparticles (Cys-c-Au NPs) on the microstructure and properties of the were investigated by Ultraviolet-visible spectroscopy (UV-Vis), Fourier-transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), and free radical scavenging ability. The results of UV-Vis and FTIR show that the cysteine was conjugated on Au NPs surface and the conjugates were found to be stable in water. The Energy-dispersive spectrometer (EDS) result shows the typical pick of the element sulfur (S) on surface of Cys-c-Au NPs. Finally, conjugates exhibited free radical scavenging ability in presence of cysteine.
Experimental Study of Micro-Milling Microchannels on Polycarbonate Substrates
Authors: Chen Pin Chuan , Pan Chang Wei
Published: June 2014

How to fabricate a disposable microfluidic device is a growing interest in many application fields and micromilling is one of the efficient approaches. The benefits of using micromilling for polymer microfluidic devices include shorter fabrication process, lower cost, easier user interface, and being capable of fabricating complicated structures. The aim of this study is to use factor analysis to determine the optimal cutting conditions in micromilling microchannels on polycarbonate substrates. The parameters included spindle speed, feed rate, and the depth of cut, and the micromilled roughness was measured by a stylus profilemeter. The smallest roughness achieved was 0.127μm with the spindle speed of 20,000rpm, feed rate of 300mm/min, and the depth of cut of 10μm. From factor analysis results, the spindle speed has the largest influence while the depth of cut has the minimized impact to the surface quality of a micromilled polycarbonate substrate.
Compressive Properties of Solid and Porous Parts Made from High Strength Steel Alloys by Direct Metal Deposition
Authors: Riza Syed H. , Masood S.H. , Wen Cui E
Published: June 2014

The potential of laser assisted Direct Metal Deposition (DMD) process, for creating structures from high strength steel alloys that can be used in engineering applications requiring high strength and greater ductility in combination with high hardness is investigated. Due to increasing interest in metallic honeycomb and sandwiched structures, solid and porous specimens are prepared and examined in similar conditions. Specimen using two different powders of 316L stainless steel and H13 tool steel alloy are generated by DMD cladding on mild steel plates as substrates. The parts are tested under quasi static compressive loading and curves plotted and analysed for stress vs. strain behaviour. The results indicate that at low laser power, solid and porous steel structures with yield strength and ductility comparable to commercial grades can be produced. Porous structures show excellent characteristics suitable for applications in newly developing field of metallic honeycombs and sandwiched structures. Low modulus of elasticity is a matter of concern, but it can be improved by heat treatment.
Computational Analysis of Single and Multiple Impacts of Low Pressure and High Pressure Cold Sprayed Aluminum Particles Using SPH
Authors: Yusof Siti Nurul Akmal , Manap Abreeza , Misran Halina , Othman Siti Zubaidah
Published: June 2014

Cold spray (CS) is a unique spraying process where the spray materials are not melted in a spray gun. Instead, the particles are kinetically deposited on the substrate at low temperature using compressed gas. This study investigates the bonding mechanism of low pressure CS (LPCS) and high pressure CS (HPCS) techniques through smoothed particle hydrodynamics (SPH) simulations, which are achieved by modeling the single and multiple particle impacts of aluminum (Al) particles on Al substrate. The impact of Al particles on the Al substrate is analyzed by evaluating the velocity, shape, temperature of the powder particles and substrate, porosity between particles, and effect of stress on the substrate. In the case of single particle impact, HPCS results in increased particle deformation. In multiple particle impact, LPCS results in low porosity. The shape of deformation, formation of pores, and residual stress of Al can be affected by the deposition process. Results indicate that LPCS is suitable for the deposition of light materials such as Al.
Surface Alloying of Copper Substrate Coated by Fe-Si by Using CO2 Laser
Authors: Taher Abulmaali M.Y.
Published: June 2014

Advanced industrial applications require materials with special surface properties such as high hardness and high wear resistance. In this study, copper substrate samples where coated by Fe-Si by using thermal evaporation technique under high vacuum, then subjected to surface laser treatment by using 720 watt CO2 laser beam. The purpose was to perform local alloying in the form of surface network of four tracks (each two are parallel and perpendicular to the other two) to produce a good thermal and electrical properties bulk material with reasonable surface hardness properties. The morphological features of the subsurface laser treated layers and their mechanical properties (microhardness) have been studied on oblique sections through the laser fused tracks. The results show that there were an intensive re-evaporation of the coating material, probably because of the high laser power density applied and the use of deep vacuum during the laser surface alloying process. Generally hardness recorded to be increased in the laser-fused tracks locations, but the bottom of the laser fused tracks showed a number of spherical voids causing a drastic decrease in the hardness values. The middle parts of the tracks showed columnar structure and elevated hardness values.
Characterization and Comparison of Thermally Sprayed Hard Coatings as Alternative to Hard Chrome Plating
Authors: Meekhanthong K. , Wirojanupatump S.
Published: June 2014

Thermal spray coatings have become one of the most potential for hard chrome replacement, particularly for wear and corrosion applications. In this study four types of hard coating materials were selected and thermally sprayed by suitable processes as the following designated codes (material/spray technique): Cr-Fe/HVOF, Cr-Ni/HVOF, WC-Ni/SF and Cr-Fe/AS. All of starting materials were characterized in order to create a correlation between spray materials and coating characteristics. SEM was employed for morphology and microstructure investigation. Particle size analysis was investigated by SEM and laser particle size analyzer. Coating characterization included surface roughness measurment by profilometer, porosity evaluation by image analysis and hardness test by Vicker microhardness tester. Microstructure of coatings was also revealed by SEM. Wear performance was evaluated by pin on disc test and dry sand rubber wheel abrasion test. Corrosion resistance was tested by potentiodynamic method. The results showed that particle size and morphology of starting powders were various depending on manufacturing method. Chemical compositions of starting materials showed great effect on coating properties and performance. Coatings deposited by HVOF and spray & fuse (SF) method showed typically dense and homogeneous structure than arc sprayed coating. WC-Ni/SF coating showed lowest abrasive wear rate compared to other thermally sprayed coatings. All Ni base coatings had significantly lower corrosion rates while Cr-Ni/HVOF coating had lowest corrosion rate. Although Cr-Ni/HVOF and WC-Ni/SF could be applicable for both wear and corrosion applications, for heat sensitive parts, Cr-Ni/HVOF coating could be a better alternative to spray and fuse.
Microstructure and Hardness of Diffusion Bonded Sialon-AISI 420 Martensitic Stainless Steel
Authors: Ibrahim Nor Nurulhuda Md. , Hussain Patthi , Awang Mokhtar
Published: June 2014

The objective of this work was to examine the microstructure, interdiffusion of elements, and hardness of joining sialon to AISI 420 martensitic stainless steel using diffusion bonding process. These materials were diffusion bonded at 1200oC for one hour under 20 MPa in a vacuum of 2.1x10-6 Torr. The microstructural analyses showed that joining sialon to nitrided steel produced thinner reaction layers and no gap or crack were formed on the sample. Gaps were produced in joining sialon to as-received steel. From the elemental analyses, alumina and iron silicides were formed at the interface layer of sialon/as-received steel joint. Alumina and smaller amount of silicides were detected at the interface layer of sialon/nitrided steel joint. Diffusion layer and parent steel of the sialon/nitrided steel joining contained nitrides. The hardness test across the joints indicated that reaction layers possessed intermediate hardness between sialon and steel. The layers contributed to ductility of the joint that help to attain the joint.
Electrophoretic Deposition of Titanium Dioxide (TiO2) Nanoparticles on Ceramic Membrane
Authors: Noorsuhana Mohd Yusof , Abdul Aziz Nurul Hidayah
Published: June 2014

The purpose of this study is to understand the electrophoresis of Titanium dioxide (TiO2) nanoparticles on ceramic membrane. The ceramic substrate was prepared using commercial ceramic filter. The effect of different types of solvent used for suspension was studied. Then, the solvent that give optimum formulation for deposited microstructure on ceramic electrode from the first stage experiment is used to study the effect of concentration on the deposition behavior of TiO2 nanoparticles during EPD technique. All the TiO2 suspension were had been characterized using Zetasizer nanoseries. The EPD was performed at 20 V DC field for 10 minutes. The deposited of TiO2 from both stage of experiment were then analyzed using ESEM. The suspension in organic solvent was found to obtain more deposited particles on ceramic membrane compared to water-based suspension. While, the concentration with 0.5 wt % TiO2 nanoparticles with zeta potential 53.6 mV was found to get smaller size and uniform microstructure. The adhesion of the TiO2 deposited layer from entire of the result on the ceramic electrode was fairly good.
Performance Analysis of a LTE Band Microstrip Antenna on FR-4 Material
Authors: Ahmed Afaz Uddin , Azim Rezaul , Mohammad Tariqul Islam , Ismail Mahamod , Islam Md. Shabiul
Published: June 2014

This paper presents the performance analysis of a LTE (Long Term Evaluation) band microstrip antenna printed on FR-4 substrate material. FR-4 substrate is a composite material of fiberglass cloth with flame resistive epoxy resin binder. It is a popular candidate for material selection in antenna design at higher bands. The proposed antenna contains a rectangular slot on the patch and covers the LTE band 7 (2.5 - 2.7 GHz). It is a cost effective approach to fabricate microstrip antenna for the LTE band 7 which is used in LTE technology throughout the world. The result shows a coverage bandwidth (<-6 dB) from 2.47 GHz – to 2.75 GHz and at 2.6 GHz the maximum achieved gain is 5.2 dB. The S-parameter is used as a comparison matrix for the simulated and fabricated antennas.
Characteristics of UV Irradiated Waste Biopolymer from Renewable Resources (Part 1)
Authors: Rus Shaiqah Mohd , Latif Najibah Abd. , Ghazali Mohd Imran , Rus Anika Zafiah M.
Published: June 2014

Waste cooking oil has proven to be a problematic material in the developed countries since people usually pour waste cooking oil into the kitchen drainage because they unaware that this waste can be recycled. Thus, in this study, the converted waste cooking oil into polymer was fabricated by using hot compression machine and named as waste biopolymer (WB). Vibration transmissibility test was conducted to determine the WB characteristics before and after UV-irradiated. It is revealed the similar vibration transmissibility responses curves were obtained at 1mm, 0.1g and 0.15g base excitation levels for the entire testing frequency except for the displacement transmissibility from base to moveable top plate at 1.5 mm. There was only one resonance peak occurred over the testing frequency which was 15 - 23 Hz for the displacement transmissibility and 15 – 25 Hz for the acceleration transmissibility test on shaking table. No other variation used on the displacement and acceleration amplitude to control the transmissibility test of UV-irradiated WB system based on shaking table. Evidently, small changes on the frequency of the vibration transmissibility were shifted to higher value of UV-irradiated WB with overall percentages of changes are below 5% except for displacement transmissibility at 1.5 mm. This shows the photo-stability of WB after UV-irradiation is high and could be used for further study.
Characteristics of UV Irradiated Waste Biopolymer from Renewable Resources (Part 2)
Authors: Rus Shaiqah Mohd , bin Ghazali Mohd Imran , Rus Anika Zafiah M.
Published: June 2014

In the developed countries, waste cooking oil has proven to be a problematic material since people usually pour waste cooking oil into the kitchen drainage because they unaware that this waste can be recycled. In this study, the waste cooking oil was converted into polymer, fabricated by using hot compression machine and named as waste biopolymer (WB). WB characteristics before and after UV-irradiated such as vibration damping, density and surface morphology were analysed in this study. Total damping ratio of WB changes more than 5% after 1000 hour UV-irradiation. UV-irradiation does not give major influence to the WB morphology since there is no big change for overall structure of UV-irradiated WB after 1000 hours of UV. Even though the density of UV-irradiated WB is decreasing with increasing exposure time to UV, but it gives good influence to the damping ratio. WB is expected to have a good service life even in a harsh UV environment thus it can be applied in many applications especially in automotive field and manufacturing packaging.
Vehicle Scheduling Model for Fresh Agriculture Products Pickup with Uncertain Demands
Authors: Rong Li Xia , Sha Huan Bin
Published: June 2014

A chance-constrained vehicle scheduling model for fresh agriculture products pickup with uncertain demands is proposed in this paper. The uncertain measure that vehicle loading will not exceed capacity constraint is presented in the model because of the uncertainty of demands. Based on uncertainty theory, when the demands are some special uncertain variables with uncertainty distribution such as linear, zigzag and normal uncertain distribution etc., the model can be transformed to a deterministic form and solved by genetic algorithm. When the demands are general uncertain variables, a hybrid genetic algorithm with uncertain simulation is presented to obtain the optimal solution. At last, to illustrate the effective of the model and algorithm, and to analyze the impact of parameters on model solution, an experiment is provided.
Nanotechnology: The Emerging Field of Civil Engineering Particularly in Developing Countries
Authors: Manzur Tanvir , Bashar Emon Ma , Islam Kabirul
Published: June 2014

Nanotechnology has taken the world of science by a storm and construction industry is no exception. The most important aspect of construction industry that can be influenced by nanotechnology is cement and concrete. Recent research on application of carbon nanotubes (CNT), both single-walled and multi-walled, shows significant increase in mechanical properties of concrete. Other properties of concrete e.g. durability, permeability, cement hydration etc. can be conveniently influenced with the help of Alkali-Silicate Reaction (ASR) studies, nanoScale Silica Fume, integration of nanoParticles in cement-synthesis and a lot other methods. And as a matter of fact, the future of cement based construction industry seems to be shaped by nanotechnology as even developing countries like Bangladesh are coming forward now-a-days to harness the potential of this rapid growing field.
Effect of LRB Position for Vibration Reduction System of Self-Anchored Cable-Stayed Suspension Bridge
Authors: Miao Feng
Published: June 2014

Larger displacement and inter-force response of the structure will be produced when self-anchored cable-stayed suspension bridge in longitudinal earthquake. Engineering practice proved that the viscous damper has obviously damping effect for structure. For the vibration reduction system of self-anchored cable-stayed suspension bridge, whose main tower is set viscous damper. This essay does the nonlinear time history analysis under the longitudinal earthquake about the vibration reduction system that considering the LRB putted in different location. Compared with the damping system that only set viscous damper, analysis results show that inter-force and displacement of control section and control node are reduced greatly in hybrid vibration control.
A New Method for Reconstruction of Corneal Topography with Placido Disk System
Authors: Gong De Wei , Chen Jian Hai , Yuan Chao , Ge Ren Kai , Zhou Ming Hua
Published: June 2014

Many methods to reconstruct the corneal topography are based on the Placido disk system. The skew rays can contribute errors to the system when using the reflection image with these methods. To overcome this limitation, a backward ray tracing technique is developed. By performing this technique, a continuous surface representation of the cornea is obtained. The error analysis shows an enhanced accuracy in reconstructing the corneal topography. The colormaps of corneal surface powers are also drawn for graphic representations of corneal topography.
Formation of Cobalt Nanoparticles from Co(OH)2 Suspension
Authors: Balela Mary Donnabelle , Yagi Shunsuke , Matsubara Eiichiro
Published: June 2014

Metallic cobalt (Co) nanoparticles with mean diameters in the range of 50-500 nm are formed by electroless deposition at room temperature in the presence of increasing concentration of NaOH. Co deposition was investigated by in situ mixed potential measurement. Increasing concentration of NaOH shifts the mixed potential negatively, leading to faster Co deposition and smaller apparent particle diameter. The decrease in mixed potential with increasing NaOH concentration is attributed to the decrease in the activity of Co2+ aquo ions in equilibrium with Co (OH)2. Consenquently, the oxidation-reduction potential of Co (II)/Co redox pair is reduced. This leads to more negative mixed potential.
Geological Survey of Canada radiocarbon dates XXVI
Authors: Blake W
Published: June 2014

This list presents 307 radiocarbon age determinations made by the Radiocarbon Dating Laboratory. They are on 294 geological samples from various areas as follows: Newfoundland (8); Labrador (6); Nova Scotia (4); Quebec (10); Ontario (7); British Columbia (10);
Yukon Territory (16); Northwest Territories, mainland (37); Northwest Territories, Arctic Archipelago (158); Alaska (4); Greenland (30); Svalbard (10); U.S.S.R. (7). Tables 1 and 2 summarize details of background and standard for the 2 L and 5 L counters during the period from September 30, 19B5 ta
July 31, 1986; Table 3 gives the number of counts used ta determine the average background and standard counting rates ; and Table 4 lists the number of different background and standard gas preparations used for counting.
The quality of working impressions for the fabrication of fixed prosthodontics prostheses (crown and bridgework)
Authors: Zu Saifudin Ahmad Syahir Ahmad , Kamaruddin Fazlieha , Ab Ghani Siti Mariam
Published: June 2014

Objective: The study was carried out to assess the quality of working impressions sent to commercial laboratories for fabrication of fixed prostheses. Materials and Methods: Impressions (n: 200) received by four dental laboratories were evaluated by two calibrated examiners. The type of work, tray designs, impression materials and techniques were recorded for each impression. Quality data on crucial details of the tooth preparations, voids at tooth preparations, tears along the finished margin line and flow of materials were documented and each criterion scored either with 2 (Good), 1 (Acceptable) or 0 (Unacceptable). The Chi-square test for independence was done for relationship analysis of the impression defects and different type of impression materials. Results: From 200 examined impressions, 53.9% were for crown works, 35.9% bridge works, 1.4% posts and cores and 8.8% for other types of work. The impression materials used were polyether (39.5%) and polyvinyl-siloxane (60.5%). The two main types of trays were metal stock (48.5%) and disposable plastic (37.5%). Impression techniques were monophase one-step technique (50.0%), putty wash two-steps technique (23.5%), putty wash one-step technique (15.5%) and dual phase one-step technique (11.0%). Overall, 64.5% of the impressions sent had unacceptable quality (0 score recorded for at least one criteria). The proportions of impression defects were significant to the type of impression materials (P < 0.05). Conclusion: The percentage of unacceptable impressions (64.5%) sent to the laboratories is a serious concern, as it contributes to the inaccuracy of the crown and bridgeworks provided to patients.
Effect of disinfection of irreversible hydrocolloid impression materials with 1% sodium hypochlorite on surface roughness and dimensional accuracy of dental stone casts
Authors: Dorner Andressa Rodrigues , Ferraz da Silva João Maurício , Uemura Eduardo Shigueyuki , Borges Alexandre LuizSouto , Fernandes Virgilio Vilas Boas , Yamamoto Eron Toshio Colauto
Published: June 2014

Aim: The aim of this study was to evaluate the effect of disinfection of commercially available irreversible hydrocolloid impression materials with 1% sodium hypochlorite on the surface roughness and dimensional accuracy of dies produced using type IV dental stone. Materials and Methods: Four different brands of irreversible hydrocolloid impression materials were used as follows: Jeltrate Plus without disinfection (GJ), Jeltrate Plus with disinfection (GJD), Hydrogum without disinfection (GH), Hidrogun with disinfection (GHD), Hidrogum 5 Days without disinfection (GH5), Hidrogum 5 Days with disinfection (GH5D), Cavex without disinfection (GC), and Cavex with disinfection (GCD). A total of 80 dies were poured using type IV dental stone and their mean surface roughness was evaluated using rugosimeter (Mitutoyo SJ-400). To conduct the dimensional alteration analysis, type IV dental stone casts were obtained from a matrix made of chemically-activated resin. They were analyzed in a coordinate-measuring machine (Brown and Sharpe). Statistics Analysis: Numerical data were analyzed using analysis of variance (ANOVA) with Tukey′s post hoc test at 5% confi dence interval. Results: Hidrogun 5 Days and Cavex showed the least surface roughness value even after 5 days. There were no significant differences in the dimensional alteration of Jeltrate (GJ and GJD) and Hidrogum (GH and GHD) in relation to the “new brands” Hidrogum 5 (GH5 and GH5D) and Cavex (GC and GCD), even after 5 days of storage. Conclusion: Considering the results obtained, it can be concluded that there was a roughness increase in the die stones poured from irreversible hydrocolloids disinfected with sodium hypochlorite.
Burden of oral diseases and dental treatment needs of an urban population in Port Harcourt, Rivers State, Nigeria
Authors: Bashiru Braimoh Omoigberai , Omotunde Soroye Modupeoluwa
Published: June 2014

Objectives: The objective of the following study is to determine the burden of oral disease and oral hygiene practices among urban population in Port Harcourt, Rivers State Nigeria. Materials and Methods: Individuals who attended the free screening exercise as part of activities to mark 2013 World Oral Health Day were recruited for this study. Data were collected through self and interviewer-administered questionnaire and clinical oral examination. Results: One hundred and sixty subjects between the ages of 5 and 78 years participated in the study. Females (59.4%) were significantly (P = 0.005) more than males (40.6%). Most of the participants (57.5%) were between 16 and 30 years. Only 33% of the screened population had visited a dentist and most of the previous visits (91%) were to the Dental Center of University of Port Harcourt Teaching Hospital. All the participants cleaned their teeth using toothpaste and toothbrush with 83.4% doing it once a daily. The prevalence of gingival bleeding and dental caries was 91.9% and 23.1%, respectively. Conclusion: The burden of oral disease and unmet dental treatment needs among the study population were high. Majority of the participants cleaned their teeth once daily; this falls short below the internationally recommended twice daily. There is a need to advocate for the creation of an enabling environment for oral health through government policies that will be focused on preventive and restorative care.
Combined treatment of a lateral incisor with palato-radicular groove: 1 year follow-up
Authors: Kamak Gülen , Akman Sümeyra
Published: June 2014

Periodontic - endodontic lesion with a palato-radicular groove as a contributing factor for periodontitis is the most important diagnostic and therapeutic challenges faced by periodontists and the maxillary lateral incisors are the most frequently affected teeth. These developmental grooves promotes the accumulation of plaque and calculus, which destroys the sulcular epithelium and later deeper parts of the periodontium, finally resulting in the formation of a severe localized periodontal lesion since proper cleaning of that site is difficult, if not impossible, for the patient. There are different types of treatment such as scaling and root planning, odontoplasty, amalgam restoration, and extraction of the tooth to treat palatogingival groove and associated periodontal bone defects. In this case, a successful management of an endodontic-periodontal combined lesion by combined treatment and guided tissue regeneration was presented.
Systemic Platelet-activating Factor Receptor Activation Augments Experimental Lung Tumor Growth and Metastasis
Authors: Hackler Patrick C. , Reuss Sarah , Konger Raymond L. , Travers Jeffrey B. , Sahu Ravi P.
Published: June 2014

Pro-oxidative stressors including cigarette smoke (CS) generate novel lipids with platelet-activated factor-receptor (PAF-R) agonistic activity mediate systemic immunosuppression, one of the most recognized events in promoting carcinogenesis. Our previous studies have established that these oxidized-PAF-R-agonists augment murine B16F10 melanoma tumor growth in a PAF-R-dependent manner because of its effects on host immunity. As CS generates PAF-R agonists, the current studies sought to determine the impact of PAF-R agonists on lung cancer growth and metastasis. Using the murine Lewis Lung Carcinoma (LLC1) model, we demonstrate that treatment of C57BL/6 mice with a PAF-R agonist augments tumor growth and lung metastasis in a PAF-R-dependent manner as these findings were not seen in PAF-R-deficient mice. Importantly, this effect was because of host rather than tumor cells PAF-R dependent as LLC1 cells do not express functional PAF-R. These findings indicate that experimental lung cancer progression can be modulated by the PAF system.
Riemann surfaces and totally real tori
Authors: Duval Julien , Gayet Damien
Published: June 2014

Given a totally real torus unknotted in the unit sphere

S^3

of

\mathbb{C}^2

, we prove the following alternative: either the torus is rationally convex and there exists a filling of the torus by holomorphic discs, or its rational hull contains a holomorphic annulus or a pair of holomorphic discs.
Determinants of Tacit Collusion in aCournot Duopoly Experiment
Authors: Anderson Lisa R. , Freeborn Beth A. , Hulbert Jason P.
Published: June 2014

We contribute to a growing literature that examines the relationship between the nature of strategic interaction and collusive behavior. We present results from a repeated Cournot duopoly experiment with treatments in which quantity choices are either strategic complements or substitutes. The initial underlying demand function allows for direct comparison with previous work utilizing a Bertrand duopoly setting. We find some evidence of collusion in the substitutes treatment, but no collusion in the complements treatment. We study an additional substitutes treatment to control for the absolute slope of the reaction functions across treatments, where we again find evidence of collusive behavior. However, using an alternate demand function parameterization where the goods are less closely related, we find no evidence of collusive behavior in either the substitutes or the complements treatment.
INTERRUPTED IN-SITU COMPRESSIVE DEFORMATION EXPERIMENTS ON MMC FOAMS IN AN XCT: EXPERIMENTS AND ESTIMATION OF DISPLACEMENT FIELDS
Authors: Losch Katharina , Schladitz Katja , Ballaschk Uta , Berek Harra , Aneziris Christos G.
Published: June 2014

The mechanical properties of a metal-matrix composite foam are investigated by interrupted in-situ compressive deformation experiments within an X-ray computed tomography device (XCT). Each in-situ experiment generates a sequence of reconstructed 3D images of the foam microstructure. From these data, the deformation field is estimated by registring the images corresponding to three consecutive steps. To this end, the generic registration framework of the itk software suite is exploited and combined with several image preprocessing steps. Both segmented (binary) images having just two grey values for foreground (strut structure) and background (pore space) and the result of the Euclidean distance transform (EDT) on pore space and solid phase are used. The estimation quality is evaluated based on a sequence of synthetic data sets, where the foam’s microstructure is modelled by a random Laguerre tessellation. For large deformations, a combination of non-rigid registration for the EDT images and partwise-rigid registration on strongly deformed regions of the binary images, yields surprisingly small estimation errors.
INCLUSION RATIO BASED ESTIMATOR FOR THE MEAN LENGTH OF THE BOOLEAN LINE SEGMENT MODEL WITH AN APPLICATION TO NANOCRYSTALLINE CELLULOSE
Authors: Niilo-Rämä Mikko , Kärkkäinen Salme , Gasbarra Dario , Lappalainen Timo
Published: June 2014

A novel estimator for estimating the mean length of fibres is proposed for censored data observed in square shaped windows. Instead of observing the fibre lengths, we observe the ratio between the intensity estimates of minus-sampling and plus-sampling. It is well-known that both intensity estimators are biased. In the current work, we derive the ratio of these biases as a function of the mean length assuming a Boolean line segment model with exponentially distributed lengths and uniformly distributed directions. Having the observed ratio of the intensity estimators, the inverse of the derived function is suggested as a new estimator for the mean length. For this estimator, an approximation of its variance is derived. The accuracies of the approximations are evaluated by means of simulation experiments. The novel method is compared to other methods and applied to real-world industrial data from nanocellulose crystalline.
QUANTIFICATION OF THE 3D MORPHOLOGY OF THE BONE CELL NETWORK FROM SYNCHROTRON MICRO-CT IMAGES
Authors: Dong Pei , Pacureanu Alexandra , Zuluaga Maria Alejandra , Olivier Cécile , Grimal Quentin , Peyrin Françoise
Published: June 2014

In the context of bone diseases research, recent works have highlighted the crucial role of the osteocyte system. This system, hosted in the lacuno-canalicular network (LCN), plays a key role in the bone remodeling process. However, few data are available on the LCN due to the limitations of current microscopy techniques, and have mainly only been obtained from 2D histology sections. Here we present, for the first time, an automatic method to quantify the LCN in 3D from synchrotron radiation micro-tomography images. After segmentation of the LCN, two binary images are generated, one of lacunae (hosting the cell body) and one of canaliculi (small channels linking the lacunae). The binary image of lacunae is labeled, and for each object, lacunar descriptors are extracted after calculating the second order moments and the intrinsic volumes. Furthermore, we propose a specific method to quantify the ramification of canaliculi around each lacuna. To this aim, a signature of the numbers of canaliculi at different distances from the lacunar surface is estimated through the calculation of topological parameters. The proposed method was applied to the 3D SR micro-CT image of a human femoral mid-diaphysis bone sample. Statistical results are reported on 399 lacunae and their surrounding canaliculi.
Le principe des responsabilités communes mais différenciées et le contrôle du non-respect : une rencontre fantasmée
Authors: Hellio Hugues
Published: June 2014

Terrain d’élection de la théorie de la compliance, les procédures de contrôle du respect des obligations étatiques des accords environnementaux multilatéraux (AEM) auraient pu constituer un cadre de réception et d’application du principe des responsabilités communes mais différenciées (PRCMD). Toutefois, les références à ce principe d’élaboration d’obligations différenciées s’avèrent impropres à un mécanisme de contrôle de l’application des obligations. Les références au PRCMD sont alors exceptionnellement explicites ou seulement implicites. Reconnaître actuellement l’application du PRCMD dans le contrôle du non-respect fait courir le risque d’une dénaturation de ce principe émergent.
Le principe des responsabilités communes mais différenciées et les déplacés climatiques en Afrique : un partage du fardeau avec les États riches ?
Authors: Hessou Tohouindji Christian , Bartenstein Kristin
Published: June 2014

En raison de leur faible niveau de développement, les États africains figurent parmi les pays les plus vulnérables aux changements climatiques. La Convention-cadre des Nations Unies sur les changements climatiques, en articulant le principe des responsabilités communes mais différenciées, oblige les États nantis à soutenir financièrement, entre autres, les mesures d’adaptation prises par les pays en voie de développement. Les auteurs montrent dans le présent article qu’il est possible d’interpréter les mesures d’adaptation envisagées par ce régime comme s’étendant aux mesures destinées à la protection des réfugiés et des déplacés internes. Par conséquent, le financement de mesures d’adaptation offert dans le cadre du régime climatique pourrait être mobilisé pour la mise en oeuvre des instruments africains relatifs aux déplacés climatiques, en particulier la Convention de l’Union africaine sur la protection et l’assistance aux personnes déplacées en Afrique, signée en 2009, à Kampala. Ce financement est en effet l’expression d’un partage différencié des responsabilités communes induites par les changements climatiques.
Analytical solutions for flow in porous media with multicomponent cation exchange reactions
Authors: Venkatraman Ashwin , Hesse Marc A. , Lake Larry W. , Johns Russell T.
Published: June 2014

Multicomponent cation exchange reactions have important applications in groundwater remediation, disposal of nuclear wastes as well as enhanced oil recovery. The hyperbolic theory of conservation laws can be used to explain the nature of displacements observed during flow with cation exchange reactions between flowing aqueous phase and stationary solid phase. Analytical solutions have been developed to predict the effluent profiles for a particular case of heterovalent cations (Na+, Ca2+ and Mg2+) and an anion (Cl−) for any combination of constant injection and constant initial composition using this theory. We assume local equilibrium, neglect dispersion and model the displacement as a Riemann problem using mass action laws, the charge conservation equation and the cation exchange capacity equation. The theoretical predictions have been compared with experimental data available at two scales—the laboratory scale and the field scale. The theory agrees well with the experimental data at both scales. Analytical theory predictions show good agreement with numerical model, developed using finite differences.
Triple water‐isotopologue record from WAIS Divide, Antarctica: Controls on glacial‐interglacial changes in 17Oexcess of precipitation
Authors: Schoenemann Spruce W. , Steig Eric J. , Ding Qinghua , Markle Bradley R. , Schauer Andrew J.
Published: June 2014

Measurements of the 17Oexcess of H2O were obtained from ice cores in West and East Antarctica. Combined with previously published results from East Antarctica, the new data provide the most complete spatial and temporal view of Antarctic 17Oexcess to date. There is a steep spatial gradient of 17Oexcess in present‐day precipitation across Antarctica, with higher values in marine‐influenced regions and lower values in the East Antarctic interior. There is also a spatial pattern to the change in 17Oexcess between the Last Glacial Maximum (LGM) and Holocene periods. At coastal locations, there is no significant change in 17Oexcess. At both the West Antarctic Ice Sheet Divide site and at Vostok, East Antarctica, the LGM to Early Holocene change in 17Oexcess is about 20 per meg. Atmospheric general circulation model (GCM) experiments show that both the observed spatial gradient of 17Oexcess in modern precipitation, and the spatial pattern of LGM to Early Holocene change, can be explained by kinetic isotope effects during snow formation under supersaturated conditions, requiring a high sensitivity of supersaturation to temperature. The results suggest that fractionation during snow formation is the primary control on 17Oexcess in Antarctic precipitation. Variations in moisture source relative humidity play a negligible role in determining the glacial‐interglacial 17Oexcess changes observed in Antarctic ice cores. Additional GCM experiments show that sea ice expansion increases the area over which supersaturating conditions occur, amplifying the effect of colder temperatures. Temperature and sea ice changes alone are sufficient to explain the observed 17Oexcess glacial‐interglacial changes across Antarctica.
Tobacco Use Among Sexual Minorities
Authors: Bryant Lawrence O. , Bowman Lorenzo
Published: June 2014

This chapter addresses tobacco use among sexual minorities. It examines research on the prevalence of tobacco use in the lesbian, gay, bisexual, and transgender (LGBT) community and discusses why tobacco use within this group continues to significantly exceed that of the general population.
Partnerships and Collaborations in Promoting Health and Wellness in Minority Communities: Lessons Learned and Future Directions
Authors: Bryant Lawrence O.
Published: June 2014

Oppression in its many forms is so ingrained in the fabric of the legal, social, economic, educational, political, and medical systems in America that it often goes unrecognized and unaddressed. The chapters in this volume explored the evasive problem of health and wellness for racial, ethnic, and sexual minorities within a framework of adult education principles.