bluuebunny/crossref_metadata_2025 huggingface dataset:
Corrosion Behavior of 13Cr Casing in Cement Synthetic Pore Solution
Authors: Sengupta Arupananda , Beck Justin , Zhao Haining , Schatz Rich S. , Ziomek-Moroz Margaret , Lvov Serguei N.
Published: August 2015

A test procedure was designed and employed for exposure and degradation testing of well cements in a simulated downhole environment of offshore deep drilling. A Class H cement sample was crushed to coarse grains and was exposed to 5 % mass NaCl(aq) solution in contact with CO2 at 100 °C and 10 MPa for 200 hours. Key ionic species were identified from the aqueous phase from the testing to develop the cement synthetic pore solution (CSPS) recipe. The CSPS was then used for corrosion characterization of high chromium well casing steel at the same conditions of the cement exposure for 60 hours. The corrosion potential in the measurements ranged between -0.4 and -0.5 V vs. SHE. The average corrosion rate of the steel samples was on the order of 0.1 mm/year, representing a worst-case scenario for degradation of the cement material, but significant for critical steel components like a well casing.
Electrochemical Measurement and Modeling of Corrosion Inhibition Efficiency of Surfactants in Salt Solutions
Authors: Zhu Yakun , Free Michael L
Published: August 2015

A new model for the prediction of corrosion inhibition efficiency of various pure surfactant and mixed surfactants in salt-containing solution is developed and validated. This prediction model is based on the combination of a modified Langmuir adsorption (MLA) sub-model or a modified Quantitative Structure Activity Relation (MQSAR) sub-model with a critical micelle concentration prediction sub-model. The overall model is very robust in predicting corrosion inhibition of various surfactants in a variety of testing systems. The model derivation is mainly based on the mixed homologous benzalkonium chlorides in NaCl-containing aqueous solution and further validated using various testing systems of surfactants. The developed corrosion inhibition prediction model provides a potential method to evaluate the effectiveness of various surfactants in corrosion inhibition under various testing solution conditions. In addition, the adsorption and inhibition mechanism of surfactants in the corresponding testing system were investigated.
Uniform Corrosion Dependence on Temperature and pH of Aluminum Alloys 2024-T3
Authors: Huang I-Wen , Buchheit Rudolph
Published: August 2015

Temperature and pH influence on uniform corrosion of 2024-T3 aluminum alloys is reported through a series of free immersion tests. Extensive results performed in various pH (3 to 10), Cl-, and temperatures (20⁰C to 80⁰C) from 1 day up to 1 month are reported to mimic real applications. A comparison with weight loss experiment is demonstrated to provide a quantitative significance of pitting versus uniform corrosion. Severity of uniform corrosion is measured at various pH, temperature, and time. Electrochemical approaches including electrochemical impedance spectroscopy (EIS) and cathodic polarization are utilized characterizing oxygen reduction reaction (ORR) and passivation at different temperatures. Passive film and corrosion product analysis is conducted by electron microscopies to assess microstructure, morphology, and corrosion product formation driven by temperature.
Mask-Patterned Wet Etching of Thin Titanium Liquid/Gas Diffusion Layers for a PEMEC
Authors: Mo Jingke , Steen Stuart M. , Retterer Scott , Cullen David A. , Terekhov Alexander , Zhang Feng-Yuan
Published: August 2015

A liquid/gas diffusion layer in a proton exchange membrane electrolyzer cell is located between the catalyst layer and flow field/current distributors, which is expected to transport electrons, heat, and reactants/products to and from the catalyst layers. In addition, conventional materials, which are typically used in PEM fuel cells, are unsuitable due to the high ohmic potential and highly oxidative environment of the oxygen electrode. In this study, a set of well-tunable and titanium thin-film liquid/gas diffusion layer with different thicknesses and porosities are designed and fabricated by using photolithography and mask-patterned wet etching techniques. The effect of mask pore size as well as different etchants on the etch rate and pore morphology of titanium is investigated. Ex-situ analysis is also performed to characterize the morphological features of the liquid/gas diffusion layer post etching. From the results of the fabrication and analysis, new methods for the fabrication of well-tunable thin film liquid/gas diffusion layers is detailed.
Performance of a High Temperature Polymer Electrolyte Membrane Fuel Cell with Low Catalyst Loading Produced by Reactive Spray Deposition Technology
Authors: Kim Siwon , Myles Timothy D. , Maric Radenka
Published: August 2015

In this study, catalyst layers with varying ratios of binder to carbon support material (I/C) for use in a high temperature phosphoric acid fuel cell were examined. The catalyst layers were deposited onto gas diffusion electrodes (GDEs) using Reactive Spray deposition technology (RSDT). RSDT is a flame based process which produces nanoscale particles of platinum through the combustion of a precursor solution containing metal organic compounds. The resulting GDEs were used to construct a 5x5 cm single cell utilizing an 85wt% phosphoric acid doped Advent membrane. Polarization scans were measured in the presence of oxygen for varying ratios of binder to carbon support material. Numerical tools have been developed based on the thin film modeling approach for catalyst layer performance and links between important physical parameters of the model and the observed performance behavior are discussed.
Impact of Cationic Impurities on Low-Pt Loading PEFC Cathodes
Authors: Ganesan Selvarani , Uddin Md. Aman , Park Jaehyung , Pasaogullari Ugur , Bonville Leonard J. , Molter Trent
Published: August 2015

The effect of Ca2+ ion contamination on a low-Pt loaded PEFC cathode (0.1 mg/cm2) was investigated systematically. Calcium sulfate dissolved in water was injected at the cathode of a single cell in aerosol form under a constant current (1 A/cm2). For comparison, a baseline test was also performed at the same conditions with deionized water. The performance decay rate for the baseline cell was 175 µV/h, whereas the CaSO4 injected cell declined much faster with a decay rate of 804 µV/h. Electrochemical, physical and spectroscopical studies confirm that injecting CaSO4 at the cathode affects the catalyst layer resulting in thinning, alters the GDL as salt deposits in the pores and no effect was seen in the polymer electrolyte membrane.
High Catalytic Activity of Ru@CoSe2/C toward Oxygen Reduction Reaction
Authors: Li Hengyi , Zhang Ying , Cheng Xuan
Published: August 2015

Carbon supported Ru@CoSe2 nanoparticles (Ru@CoSe2/C) were prepared through a simple and facile two-step route. The CoSe2 nanoparticles were first obtained by microwave assisted method, and then followed by galvanic substitution of Ru on CoSe2. It was found that the introduction of a small amount of Ru into CoSe2 led to a core-satellite like structure in which the disordered Ru nanoparticles were adsorbed on CoSe2 nanocrystallites. Compared with CoSe2/C and Ru85Se15/C, the Ru@CoSe2/C exhibited higher catalytic activity toward oxygen reduction reaction due to the enhanced Ru utilization through Ru and CoSe2 interaction. The half-wave potential of 0.548 V (vs. RHE) and the cathodic current density of 3.37 mA cm-2 at 0.6 V were obtained for Ru@CoSe2/C in an acidic solution.
Different Carbide Derived Nanoporous Carbon Supports and Electroreduction of Oxygen
Authors: Härk Eneli , Jäger Rutha , Tallo Indrek , Thomberg Thomas , Kurig Heisi , Russina Margarita , Kardjilov Nikolay , Manke Ingo , Hilger André , Lust Enn
Published: August 2015

Using rotating disc electrode technique, the oxygen reduction reaction in 0.1M KOH was studied at various micromesoporous carbide derived carbon powders, synthesized from various binary metal carbides. The catalytic activity and mechanism noticeable depends on the hierarchical structure of the nanoporous carbon electrode. The activation with CO2 increases the differential volume of pores and proportion of mesopores in carbon matrix. It was shown that the partially graphitized carbon C(Mo2C) with a large number of edge plane sites has higher electrocatalytic activity toward oxygen reduction in alkaline media compared with other amorphous or partly graphitized carbons studied. The corresponding relative catalytic activity of catalysts increases in the following order: C(WTiC2) < Vulcan < C(TiC) < C(TiC)-A1 ≤ C(TiC)-A2 < C(Mo2C)-A < C(Mo2C).
Electrochemical Reduction of Carbon Dioxide on Single-Crystal Copper Membrane
Authors: Yoshihara Naoki , Arita Mai , Noda Masaru
Published: August 2015

The selective electrochemical reduction of carbon dioxide (CO2) was demonstrated over single-crystal copper membranes. The crystalline copper membranes were deposited on specific support substrates that were c-plane sapphire for Cu(111), MgO(100) for Cu(100), and MgO(110) for Cu(110). Methane (CH4) and ethylene (C2H4) formation in CO2 electrochemical reduction was more favorable on Cu(111) membranes than that on polycrystalline copper plates. The electrolyte type that CO2 gas was effectively dissolved in, was important to significantly maintain electrochemical activity. The product selectivity for CO2 conversion was strongly dependent on the crystal structure of the copper surface.
Effects on Wetting Agents in Cationic Contamination and Mitigation in PEFCs
Authors: Park Jaehyung , Uddin Md. Aman , Ganesan Selvarani , Pasaogullari Ugur , Bonville Leonard J. , Molter Trent
Published: August 2015

A role of the gas diffusion layer (GDL) in cationic contamination and mitigation has been studied with isopropanol (IPA) as a wetting agent of the GDL. For this test, the catalyst coated membrane is not in direct contact with the contaminating solution, being separated by both the GDL and the gasket. The hydrophobic layer of the GDL acts as a barrier to the transport of foreign cations into a membrane. The effect on performance of the added 15% IPA as a wetting agent in the cationic solution was verified by an ex-situ soak method and by an in-situ injection method for both mitigation and recovery processes. Wetting forces and contact angles were measured to quantify the GDL wettability changes attributed to the added IPA solution. The cationic mitigation solution and the acid cleaning solution can transport across the GDL into the CCM, but the overall cell performance was not fully recovered.
Aberrant REDD1-mTORC1 responses to insulin in skeletal muscle from Type 2 diabetics
Authors: Williamson David L. , Dungan Cory M. , Mahmoud Abeer M. , Mey Jacob T. , Blackburn Brian K. , Haus Jacob M.
Published: August 2015

The objective of this study was to establish whether alterations in the REDD1-mTOR axis underlie skeletal muscle insensitivity to insulin in Type 2 diabetic (T2D), obese individuals. Vastus lateralis muscle biopsies were obtained from lean, control and obese, T2D subjects under basal and after a 2-h hyperinsulinemic (40 mU·m−2·min−1)-euglycemic (5 mM) clamp. Muscle lysates were examined for total REDD1, and phosphorylated Akt, S6 kinase 1 (S6K1), 4E-BP1, ERK1/2, and MEK1/2 via Western blot analysis. Under basal conditions [(-) insulin], T2D muscle exhibited higher S6K1 and ERK1/2 and lower 4E-BP1 phosphorylation ( P < 0.05), as well as elevations in blood cortisol, glucose, insulin, glycosylated hemoglobin ( P < 0.05) vs. lean controls. Following insulin infusion, whole body glucose disposal rates (GDR; mg/kg/min) were lower ( P < 0.05) in the T2D vs. the control group. The basal-to-insulin percent change in REDD1 expression was higher ( P < 0.05) in muscle from the T2D vs. the control group. Whereas, the basal-to-insulin percent change in muscle Akt, S6K1, ERK1/2, and MEK1/2 phosphorylation was significantly lower ( P < 0.05) in the T2D vs. the control group. Findings from this study propose a REDD1-regulated mechanism in T2D skeletal muscle that may contribute to whole body insulin resistance and may be a target to improve insulin action in insulin-resistant individuals.
Functional coupling between sodium-activated potassium channels and voltage-dependent persistent sodium currents in cricket Kenyon cells
Authors: Takahashi Izumi , Yoshino Masami
Published: August 2015

In this study, we examined the functional coupling between Na+-activated potassium (KNa) channels and Na+ influx through voltage-dependent Na+ channels in Kenyon cells isolated from the mushroom body of the cricket Gryllus bimaculatus. Single-channel activity of KNa channels was recorded with the cell-attached patch configuration. The open probability ( Po) of KNa channels increased with increasing Na+ concentration in a bath solution, whereas it decreased by the substitution of Na+ with an equimolar concentration of Li+. The Po of KNa channels was also found to be reduced by bath application of a high concentration of TTX (1 μM) and riluzole (100 μM), which inhibits both fast ( INaf) and persistent ( INaP) Na+ currents, whereas it was unaffected by a low concentration of TTX (10 nM), which selectively blocks INaf. Bath application of Cd2+ at a low concentration (50 μM), as an inhibitor of INaP, also decreased the Po of KNa channels. Conversely, bath application of the inorganic Ca2+-channel blockers Co2+ and Ni2+ at high concentrations (500 μM) had little effect on the Po of KNa channels, although Cd2+ (500 μM) reduced the Po of KNa channels. Perforated whole cell clamp analysis further indicated the presence of sustained outward currents for which amplitude was dependent on the amount of Na+ influx. Taken together, these results indicate that KNa channels could be activated by Na+ influx passing through voltage-dependent persistent Na+ channels. The functional significance of this coupling mechanism was discussed in relation to the membrane excitability of Kenyon cells and its possible role in the formation of long-term memory.
Effects of changing skin mechanics on the differential sensitivity to surface compliance by tactile afferents in the human finger pad
Authors: Hudson Kathryn M. , Condon Melia , Ackerley Rochelle , McGlone Francis , Olausson Håkan , Macefield Vaughan G. , Birznieks Ingvars
Published: August 2015

It is not known how changes in skin mechanics affect the responses of cutaneous mechanoreceptors in the finger pads to compression forces. We used venous occlusion to change the stiffness of the fingers and investigated whether this influenced the firing of low-threshold mechanoreceptors to surfaces of differing stiffness. Unitary recordings were made from 10 slowly adapting type I (SAI), 10 fast adapting type I (FAI) and 9 slowly adapting type II (SAII) units via tungsten microelectrodes inserted into the median nerve at the wrist. A servo-controlled stimulator applied ramp-and-hold forces (1, 2, and 4 N) at a constant loading and unloading rate (2 N/s) via a flat 2.5-cm-diameter silicone disk over the center of the finger pad. Nine silicone disks (objects), varying in compliance, were used. Venous occlusion, produced by inflating a sphygmomanometer cuff around the upper arm to 40 ± 5 mmHg, was used to induce swelling of the fingers and increase the compliance of the finger pulp. Venous occlusion had no effect on the firing rates of the SAI afferents, nor on the slopes of the relationship between mean firing rate and object compliance at each amplitude, but did significantly reduce the slopes for the FAI afferents. Although the SAII afferents possess a poor capacity to encode changes in object compliance, mean firing rates were significantly lower during venous occlusion. The finding that venous occlusion had no effect on the firing properties of SAI afferents indicates that these afferents preserve their capacity to encode changes in object compliance, despite changes in skin mechanics.
Membrane potential dynamics of populations of cortical neurons during auditory streaming
Authors: Farley Brandon J. , Noreña Arnaud J.
Published: August 2015

How a mixture of acoustic sources is perceptually organized into discrete auditory objects remains unclear. One current hypothesis postulates that perceptual segregation of different sources is related to the spatiotemporal separation of cortical responses induced by each acoustic source or stream. In the present study, the dynamics of subthreshold membrane potential activity were measured across the entire tonotopic axis of the rodent primary auditory cortex during the auditory streaming paradigm using voltage-sensitive dye imaging. Consistent with the proposed hypothesis, we observed enhanced spatiotemporal segregation of cortical responses to alternating tone sequences as their frequency separation or presentation rate was increased, both manipulations known to promote stream segregation. However, across most streaming paradigm conditions tested, a substantial cortical region maintaining a response to both tones coexisted with more peripheral cortical regions responding more selectively to one of them. We propose that these coexisting subthreshold representation types could provide neural substrates to support the flexible switching between the integrated and segregated streaming percepts.
Auditory midbrain representation of a break in interaural correlation
Authors: Wang Qian , Li Liang
Published: August 2015

The auditory peripheral system filters broadband sounds into narrowband waves and decomposes narrowband waves into quickly varying temporal fine structures (TFSs) and slowly varying envelopes. When a noise is presented binaurally (with the interaural correlation being 1), human listeners can detect a transient break in interaural correlation (BIC), which does not alter monaural inputs substantially. The central correlates of BIC are unknown. This study examined whether phase locking-based frequency-following responses (FFRs) of neuron populations in the rat auditory midbrain [inferior colliculus (IC)] to interaurally correlated steady-state narrowband noises are modulated by introduction of a BIC. The results showed that the noise-induced FFR exhibited both a TFS component (FFRTFS) and an envelope component (FFREnv), signaling the center frequency and bandwidth, respectively. Introduction of either a BIC or an interaurally correlated amplitude gap (which had the summated amplitude matched to the BIC) significantly reduced both FFRTFS and FFREnv. However, the BIC-induced FFRTFS reduction and FFREnv reduction were not correlated with the amplitude gap-induced FFRTFS reduction and FFREnv reduction, respectively. Thus, although introduction of a BIC does not affect monaural inputs, it causes a temporary reduction in sustained responses of IC neuron populations to the noise. This BIC-induced FFR reduction is not based on a simple linear summation of noise signals.
Motor signatures in autism spectrum disorder: the importance of variability
Authors: Parma Valentina , de Marchena Ashley B.
Published: August 2015

In a recent study, Wang et al. ( J Neurophysiol 113: 1989–2001, 2015) used a precision grip force control task to unveil the contribution of feedforward and feedback mechanisms to sensorimotor dysfunction in autism spectrum disorder (ASD). Impairment of both motor control mechanisms was observed, along with significant variability in the motor response. In this Neuro Forum article we discuss these findings within the conceptual framework of the grasping circuit and within the broader context of clinical and research applications based on motor behavior.
A Relative Reliability Approach for Direct Displacement-Based Seismic Design of Partially Prestressed Reinforced Concrete Frame Structures
Authors: Jian Bin , Lei Chaoyi , Liao Pingping
Published: August 2015

A relative reliability approach for Direct Displacement-Based Design (DDBD) is first proposed in this paper, which is based on the average reliability level implicit in current Chinese design codes. By introducing a relative reliability coefficientα, the determination of reliability from DDBD is transformed to the calculation of its ratio to the average reliability of current Chinese codes. This approach not only follows the reliability principle of current Chinese codes, but also avoids the complex calculation of reliability in general. The calculation of reliability at any performance level can be transformed to the nominal reliability of frequent earthquake for the expected earthquake risk level. Meanwhile, based on the assumption of elasticity, it is shown that, under frequent earthquake risk, the calculated base shear derived from DDBD theoretically equals that from force-based design (FBD). Therefore, a revised calculation of section bearing capacity for DDBD, which follows the expression in current Chinese codes, is advised, according to the numerical study of 24 examples of Partially Prestressed Reinforced Concrete (PPRC) frame structures. Finally, this proposed approach is verified to be effective and superior by a comparative analysis of 10 examples of PPRC frames.
Torsion Wave Solutions in Yang-Mielke Theory of Gravity
Authors: Pasic Vedad , Barakovic Elvis
Published: August 2015

The approach of metric-affine gravity initially distinguishes it from Einstein’s general relativity. Using an independent affine connection produces a theory with 10 + 64 unknowns. We write down the Yang-Mills action for the affine connection and produce the Yang-Mills equation and the so-called complementary Yang-Mills equation by independently varying with respect to the connection and the metric, respectively. We call this theory the Yang-Mielke theory of gravity. We construct explicit spacetimes with pp-metric and purely axial torsion and show that they represent a solution of Yang-Mills theory. Finally we compare these spacetimes to existing solutions of metric-affine gravity and present future research possibilities.
Inflammatory Pseudotumor of the Liver withEscherichia coliin the Sputum
Authors: Narayan Sreenath , Nayak Ashwini , King Chris L.
Published: August 2015

Inflammatory pseudotumor is a nonmalignant lesion that mimics malignant lesions and has been reported to occur at various sites throughout the body. Though it has been reported as a reaction to infection, the true etiology of the lesion is unknown. In this report, we present the case of a patient with a liver lesion of unknown origin. Through a series of imaging studies, we were able to observe the locally aggressive nature of this lesion as it rapidly eroded into the lung. Sputum cultures showed growth ofE. coli, indicatingE. coliinfection as a possible etiology of this lesion. Pathology was consistent with inflammatory pseudotumor.
Adaptive Streaming of Scalable Videos over P2PTV
Authors: Lahbabi Youssef , Ibn Elhaj El Hassan , Hammouch Ahmed
Published: August 2015

In this paper, we propose a new Scalable Video Coding (SVC) quality-adaptive peer-to-peer television (P2PTV) system executed at the peers and at the network. The quality adaptation mechanisms are developed as follows: on one hand, the Layer Level Initialization (LLI) is used for adapting the video quality with the static resources at the peers in order to avoid long startup times. On the other hand, the Layer Level Adjustment (LLA) is invoked periodically to adjust the SVC layer to the fluctuation of the network conditions with the aim of predicting the possible stalls before their occurrence. Our results demonstrate that our mechanisms allow quickly adapting the video quality to various system changes while providing best Quality of Experience (QoE) that matches current resources of the peer devices and instantaneous throughput available at the network state.
Harmful Chemicals in Soil and Risk Assessment of an Abandoned Open Dumpsite in Eastern China
Authors: Huang Ying , Li YongXia , Yang Jian , Xu MinMin , Sun Bo , Gao FuWei , Wang Ning
Published: August 2015

The concentrations of pollutants in soil samples collected in and around a dumpsite in Heze, Shandong, China, were investigated, and the potential ecological and health risks of these pollutants were assessed. Seventeen soil samples from five different locations were analysed for pollution characteristics, and the target pollutants included inorganic pollutants and heavy metals as well as volatile organic compounds/semivolatile organic compounds (VOCs/SVOCs). Results showed that the mean concentration level of each pollutant from the interior area was relatively higher than that from the boundary area of the dumpsite. Inorganic pollutants and heavy metals were detected in all of the soil samples. According to potential ecological risk assessment with environmental background values of Shandong as screening values, heavy metals in majority of the samples pose low ecological risk to the ecosystem except Hg. Hg poses a considerable or very high risk because of its high levels of accumulation. In consideration of future land use pattern, human health risks derived from environmental exposure to heavy metals were assessed. Carcinogenic risk and noncarcinogenic hazards for adults are acceptable, while noncarcinogenic hazards for children exceed the safety threshold. The health risks are primarily attributed to oral exposure to As and Cr.
Motor Neuron Diseases in Sub-Saharan Africa: The Need for More Population-Based Studies
Authors: Quansah Emmanuel , Karikari Thomas K.
Published: August 2015

Motor neuron diseases (MNDs) are devastating neurological diseases that are characterised by gradual degeneration and death of motor neurons. Major types of MNDs include amyotrophic lateral sclerosis (ALS) and spinal muscular atrophy (SMA). These diseases are incurable, with limited disease-modifying treatment options. In order to improve MND-based biomedical research, drug development, and clinical care, population-based studies will be important. These studies, especially among less-studied populations, might identify novel factors controlling disease susceptibility and resistance. To evaluate progress in MND research in Africa, we examined the published literature on MNDs in Sub-Saharan Africa to identify disease prevalence, genetic factors, and other risk factors. Our findings indicate that the amount of research evidence on MNDs in Sub-Saharan Africa is scanty; molecular and genetics-based studies are particularly lacking. While only a few genetic studies were identified, these studies strongly suggest that there appear to be population-specific causes of MNDs among Africans. MND genetic underpinnings vary among different African populations and also between African and non-African populations. Further studies, especially molecular, genetic and genomic studies, will be required to advance our understanding of MND biology among African populations. Insights from these studies would help to improve the timeliness and accuracy of clinical diagnosis and treatment.
Vitamin K Deficiency Embryopathy from Hyperemesis Gravidarum
Authors: Lane Andrew S. , Stallworth Jennifer L. , Eichelberger Kacey Y. , Trofatter Kenneth F.
Published: August 2015

A 21-year-old primigravida had a pregnancy complicated by hyperemesis gravidarum (HG) beginning at 7-week gestation. Despite medical therapy, she lost 18% of her prepregnancy weight. Early ultrasound at 14 weeks demonstrated a flattened facial profile with nasal hypoplasia (Binder phenotype) consistent with vitamin K deficiency from HG. She had a percutaneous endoscopic gastrojejunostomy tube placed for enteral feeding at 15-week gestation. At repeated anatomy ultrasound at 21-week gestation, delivery, and postnatal pediatric genetics exam, nasal hypoplasia was consistent with vitamin K deficiency embryopathy from HG. Nausea and vomiting of pregnancy is a common condition. HG, the most severe form, has many maternal and fetal effects. Evaluation of vitamin K status could potentially prevent this rare and disfiguring embryopathy.
A Rare Case of a Lost Suture Needle during Third Molar Surgery
Authors: Aktop Sertac , Gocmen Gokhan , Özturk M. Elif , Gonul Onur , Varol Altan
Published: August 2015

The authors report a case that is started with a simple upper third molar’s surgical extraction and a broken 3.0 suture needle tip incident occurred. Broken fragment’s localization has been detected with 3D cone beam computed tomography (CBCT). Needle tip has been reached with the help of CBCT vision. CBCT’s benefits have been discussed on these types of cases and further migration of the needle tip during surgical procedure is reported.
Tunnel Probabilistic Structural Analysis Using the FORM
Authors: Mirzaeian Yousef , Shahriar Kourosh , Sharifzadeh Mostafa
Published: August 2015

In this paper tunnel probabilistic structural analysis (TuPSA) was performed using the first order reliability method (FORM). In TuPSA, a tunnel performance function is defined according to the boundary between the structural stability and instability. Then the performance function is transformed from original space into the standard normal variable space to obtain the design point, reliability index, and also the probability of tunnel failure. In this method, it is possible to consider the design factors as the dependent or independent random parameters with arbitrary probability distributions. A software code is developed to perform the tunnel probabilistic structural analysis (TuPSA) using the FORM. For validation and verification of
TuPSA, a typical tunnel example with random joints orientations as well as mechanical properties has been studied. The results of TuPSA were compared with those obtained from Monte-Carlo simulation.
The results show, in spite of deterministic analysis which indicates that the rock blocks are stable, that TuPSA resulted in key-blocks failure with certain probabilities. Comparison between probabilistic and deterministic analyses results indicates that probabilistic results, including the design point and probability of failure, are more rational than deterministic factor of safety.
Experimental Study of the Gas Engine Driven Heat Pump with Engine Heat Recovery
Authors: Zhang Wei , Wang Tao , Zheng Sulu , Peng Xueyuan , Wang Xiaolin
Published: August 2015

Gas engine driven heat pumps (GEHPs) represent one of practical solutions to effectively utilize fossil fuel energy and reduce environmental pollution. In this paper, the performance characteristics of the GEHP were investigated experimentally with engine heat recovery. A GEHP test facility was set up for this purpose. The effects of several important factors including engine speed, ambient temperature, condenser water flow rate, and condenser water inlet temperature on the system performance were studied over a wide range of operating conditions. The results showed that the engine waste heat accounted for about 40–50% of the total heat capacity over the studied operating conditions. It also showed that engine speed and ambient temperature had significant effects on the GEHP performance. The coefficient of performance (COP) and the primary energy ratio (PER) decreased by 14% and 12%, respectively, as engine speed increased from 1400 rpm to 2000 rpm. On the other hand, the COP and PER of the system increased by 22% and 16%, respectively, with the ambient temperature increasing from 3 to 12°C. Furthermore, it was demonstrated that the condenser water flow rate and condenser water inlet temperature had little influence on the COP of the heat pump and the PER of the GEHP system.
Feature Extraction in Densely Sensed Environments: Extensions to Multiple Broadcast Domains
Authors: Vahabi Maryam , Gupta Vikram , Albano Michele , Rangarajan Raghuraman , Tovar Eduardo
Published: August 2015

The vision of the Internet of Things (IoT) includes large and dense deployment of interconnected smart sensing and monitoring devices. This vast deployment necessitates collection and processing of large volume of measurement data. However, collecting all the measured data from individual devices on such a scale may be impractical and time-consuming. Moreover, processing these measurements requires complex algorithms to extract useful information. Thus, it becomes imperative to devise distributed information processing mechanisms that identify application-specific features in a timely manner and with low overhead. In this paper, we present a feature extraction mechanism for dense networks that takes advantage of dominance-based medium access control (MAC) protocols to (i) efficiently obtain global extrema of the sensed quantities, (ii) extract local extrema, and (iii) detect the boundaries of events, by using simple transforms that nodes employ on their local data. We extend our results for a large dense network with multiple broadcast domains (MBD). We discuss and compare two approaches for addressing the challenges with MBD and we show through extensive evaluations that our proposed distributed MBD approach is fast and efficient at retrieving the most valuable measurements, independent of the number sensor nodes in the network.
Analysis of Prostate Cancer Susceptibility Variants in South African Men: Replicating Associations on Chromosomes 8q24 and 10q11
Authors: Fernandez Pedro , Salie Muneeb , du Toit Danielle , van der Merwe Andre
Published: August 2015

Genome-wide association studies (GWAS) have implicated single nucleotide polymorphisms (SNPs) on chromosomes 2p15, 6q25, 7p15.2, 7q21, 8q24, 10q11, 10q26, 11q13, 17q12, 17q24, 19q13, and Xp11, with prostate cancer (PCa) susceptibility and/or tumour aggressiveness, in populations of African, European, and Asian ancestry. The objective of this study was to confirm these associations in South African Mixed Ancestry and White men. We evaluated 17 prioritised GWAS SNPs in South African cases (331 Mixed Ancestry and 155 White) and controls (178 Mixed Ancestry and 145 White). The replicated SNP associations for the different South African ethnic groups were rs7008482 (8q24) (p=2.45×10-5), rs6983267 (8q24) (p=4.48×10-7), and rs10993994 (10q11) (p=1.40×10-3) in Mixed Ancestry men and rs10993994 (p=1.56×10-9) in White men. No significant associations were observed for the analyses stratified by disease aggressiveness in the individual and the combined population group analysis. The present study demonstrates that a number of known PCa susceptibility variants may contribute to disease susceptibility in South African men. Larger genetic investigations extended to other South African population groups are warranted to confirm the role of these and other SNPs in disease susceptibility.
Elevated Phospholipid Transfer Protein in Subjects with Multiple Sclerosis
Authors: Garvin Roy A.
Published: August 2015

An anomaly in the plasma proteins of patients with multiple sclerosis detectable on SDS-PAGE has been reported. The molecular weight of the anomaly was the same as the phospholipid transfer protein. A metabolic protein was involved in lipid homeostasis and remodeling of the high density lipoproteins. We have identified the anomaly as the phospholipid transfer protein by western blot using antiphospholipid transfer antibodies. Activity assays showed that the phospholipid transfer activity was elevated in fasted plasma samples from subjects with MS compared to controls. Sequence analysis of the gene encoding the phospholipid transfer protein did not identify any mutations in the genetic structure, suggesting that the increase in activity was not due to structural changes in the protein, but may be due to one of the other proteins with which it forms active complexes. Altered phospholipid transfer activity is important because it could be implicated in the decreased lipid uptake and abnormal myelin lipids observed in multiple sclerosis. It has been shown that alteration in myelin lipid content is an epitope for autoimmunity. Therefore, lipid changes due to a defect in phospholipid transfer and/or uptake could potentially influence the course of the disease. Further research is needed to elucidate the role of the phospholipid transfer protein in subjects with multiple sclerosis.
Mathematical Modeling of Heat and Mass Transfer Processes with Chemical Reaction at Polymeric Material Ignition by Several Small-Size Hot Particles
Authors: Glushkov Dmitrii O. , Strizhak Pavel A.
Published: August 2015

Numerical research of interconnected heat and mass transfer processes in the “two hot particles—polymeric material—air” system was executed. The joint effect of several local heat sources on the main integrated characteristic of ignition process (ignition delay time) was established. Two ignition models characterized by the relative positioning of hot particles on a polymeric material surface were revealed. Besides, there were established characteristics of local heat sources and the distance between them (700  K<Tp<1150 K andL>1.5orTp>1150 K and0.25<L<1.5)when regularities of heat and mass transfer processes in the “two hot particles—polymeric material—air” system are similar to regularities of heat and mass transfer processes in the “single hot particle—polymeric material—air” system.
Mineralization of Quinoline by BDD Anodes: Variable Effects and Its Effluent Characteristics
Authors: Wang C. R. , Wang J. , Ma X. G. , Li H. , Zhang S. Z.
Published: August 2015

BDD anodes were selected for quinoline mineralization and influence of operating parameters, such as current density, initial quinoline concentration, supporting electrolyte, and initial pH was investigated. Based on the consideration of quinoline removal efficiency and average current efficiency, at initial quinoline concentration of 50 mg L−1and pH of 7, the optimal condition was confirmed as current density of 75 mA cm−2, electrolysis time of 1.5 h, and Na2SO4concentration of 0.05 mol L−1by orthogonal test. At different electrolysis time, its effluent characteristics were focused on. The biodegradability (the ratio between BOD5and COD) was enhanced from initial 0.02 to 0.57 at 90 min. The specific oxygen uptake rate was used to assess effluent toxicity, and the value gradually reduced with decreasing effluent organic concentration with mean value of 5.51, 4.19, and 2.20 mgO2 g−1MLSS at electrolysis time of 15, 30, and 45 min, respectively. Compared with control sample (prepared with glucose), the effluent of quinoline mineralization showed obvious inhibition effect on microorganisms at electrolysis time of 15 min, and then it was significantly faded at 30 min and 45 min.
Performance Study of a Four-Bed Silica Gel-Water Adsorption Chiller with the Passive Heat Recovery Scheme
Authors: He Zhilong , Wang Xiaolin , Chua Hui Tong
Published: August 2015

Adsorption chiller technology is one of the effective means to convert waste thermal energy into effective cooling, which substantially improves energy efficiency and lowers environmental pollution. This paper uses an improved lump-parameter design model to theoretically and experimentally evaluate the efficacy of the passive heat recovery scheme as applied to a four-bed adsorption chiller. Results show that the model can accurately track the experimental temporal system outlet temperatures. The performance predictions from this model compare favourably with experimental results. At rated temperature conditions and over a wide range of cycle times, both the cooling capacity and COP can be predicted to within 12.5%. The analyses indicate that the model can be used confidently as a design tool for a four-bed adsorption chiller and the passive heat recovery scheme can effectively improve the system performance.
Sorption of Pyrene by Clay Minerals Coated with Dissolved Organic Matter (DOM) from Landfill Leachate
Authors: Wu Pingxiao , Wen Yong , Xiang Yun , Zhou Jianbing , Du Jianwei , Zhu Nengwu , Li Ping
Published: August 2015

Interactions of dissolved organic matter (DOM) from landfill leachate with clays could affect significantly the fate of hydrophobic organic compounds (HOCs) in soils. The complexes of montmorillonite (MT) and kaolinite (KL) with DOM extracted from landfill leachate were prepared under controlled conditions, termed CMT and CKL, respectively. The bare clays and their complexes were characterized by powder X-ray diffraction (XRD), Fourier transform infrared (FTIR), thermogravimetry (TG), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM). Batch experiments were designed to investigate the sorption behavior of pyrene onto the clays in the presence of DOM. The maximum sorption capacities of pyrene on MT, CMT, KL, and CKL were 22.18, 38.96, 42.00, and 44.99 μg·g−1, respectively, at the initial concentration of 1000 ± 150 μg·L−1. The sorption isotherms of pyrene by the bare clays followed the Henry model well, whereas the Freundlich sorption isotherm provided a better fit to the equilibrium data of the sorption by the complexes. The role of montmorillonite and kaolinite complexes with DOM in the retention of pyrene in soils was different. This may be due to the different crystal structures between montmorillonite and kaolinite.
Heat and Mass Transfer for MHD Viscoelastic Fluid Flow over a Vertical Stretching Sheet with Considering Soret and Dufour Effects
Authors: Rashidi Mohammad Mehdi , Ali Mohamed , Rostami Behnam , Rostami Peyman , Xie Gong-Nan
Published: August 2015

The homotopy analysis method (HAM) with two auxiliary parameters is employed to examine heat and mass transfer in a steady two-dimensional magneto hydrodynamic viscoelastic fluid flow over a stretching vertical surface by considering Soret and Dufour effects. The two-dimensional boundary-layer governing partial differential equations are derived by considering the Boussinesq approximation. The highly nonlinear ordinary differential forms of momentum, energy, and concentration equations are obtained by similarity transformation. These equations are solved analytically in the presence of buoyancy force. The effects of different involved parameters such as magnetic field parameter, Prandtl number, buoyancy parameter, Soret number, Dufour number, and Lewis number on velocity, temperature, and concentration profiles are plotted and discussed. The effect of the second auxiliary parameter is also illustrated. Results show that the effect of increasing Soret number or decreasing Dufour number tends to decrease the velocity and temperature profiles (increase in Sr cools the fluid and reduces the temperature) while enhancing the concentration distribution.
Whole Exome- and mRNA-Sequencing of an AT/RT Case Reveals Few Somatic Mutations and Several Deregulated Signalling Pathways in the Context ofSMARCB1Deficiency
Authors: Sandgren Johanna , Holm Stefan , Marino Ana Maria , Asmundsson Jurate , Grillner Pernilla , Nistér Monica , Díaz de Ståhl Teresita
Published: August 2015

Background. AT/RTs are rare aggressive brain tumours, mainly affecting young children. Most cases present with genetic inactivation ofSMARCB1, a core member of the SWI/SNF chromatin-remodeling complex. We have performed whole exome- and mRNA-sequencing on an early onset AT/RT case for detection of genetic events potentially contributing to the disease.Results. Ade novogermline variant inSMARCB1, c.601C>T p.Arg201∗, in combination with somatic deletion of the healthy allele is likely the major tumour causing event. Only seven somatic small scale mutations were discovered (hittingSEPT03, H2BFM, ZIC4, HIST2H2AB, ZIK1, KRTAP6-3, andIFNA8). All were found with subclonal allele frequencies (range 5.7–17%) and none were expressed. However, besidesSMARCB1, candidate genes affected by predicted damaging germline variants that were expressed were detected (KDM5C, NUMA1, andPCM1). Analysis of differently expressed genes revealed many dysregulated pathways in the tumour, such as cell cycle, CXCR4 pathway, GPCR-signalling, and neuronal system.FGFR1, CXCR4, andMDKwere upregulated and may represent possible drug targets.Conclusion. The loss ofSMARCB1function leads to AT/RT development and deregulated genes and pathways. Additional predisposing events may however contribute. Studies utilizing NGS technologies in larger cohorts will probably identify recurrent genetic and epigenetic alterations and molecular subgroups with implications for clinical practice and development of targeted therapies.
Design, Optimization, and Mechanical Property Analysis of a Submicrometric Aluminium Alloy Connecting Rod
Authors: Fuertes J. P. , León J. , Luis C. J. , Salcedo D. , Puertas I. , Luri R.
Published: August 2015

Ultrafine grained materials have a great deal of both scientific and technological interest because they allow outstanding properties to be obtained. An improvement in the mechanical strength and in the ductility and a better fatigue behaviour are properties to be expected with these materials. However, in spite of the great number of scientific publications that deals with the mechanical property improvement, the number of practical applications of these materials is scant. In this present research work, equal channel angular pressing (ECAP) is used as a severe plastic deformation process (SPD) to obtain billets which are subsequently isothermally forged to obtain a connecting rod with submicrometric grain size. The optimization of the design process is shown as well as the die design. The objective variables to be fulfilled are the correct filling of the die and the required force to obtain the part. Moreover, a comparison is also included between the mechanical properties thus obtained and those obtained with traditional methods. Moreover, optical and SEM micrographs are also included in this research work.
Predictors of Self-Management Behaviors in Older Adults with Hypertension
Authors: Douglas Brenda M. , Howard Elizabeth P.
Published: August 2015

The purpose of this study was to develop a prediction model of demographic and sociobehavioral characteristics common among older adults with hypertension (HTN) who engage in self-management behavior. A descriptive, correlational predictive design was used to collect data at 14 faith-based and senior citizen organizations in a major urban northeastern city. Participants ranged in age from 63 to 96 with a mean age of 77 (SD 6.9). A 33-item questionnaire was used to gather data on 15 explanatory and 5 outcome variables. Instruments were the Perceived Stress Scale, the Duke Social Support Index, the stage of change for physical activity scale, and the DASH Food Frequency Questionnaire. Correlation and regression analyses were used to test the hypothesis. Results indicate there is a common set of characteristics such as higher stage of change, reading food labels, and higher self-rated health that can predict the older adult’s likelihood to engage in hypertension self-management behavior. The significant correlations found in this preliminary study warrant further study and validation. Findings are clinically relevant as knowledge of demographic and sociobehavioral characteristics associated with engagement in self-management behavior enables health care clinicians to support and encourage older adults to improve management of this common, chronic condition.