bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental Research on Reactive Reinforcement Method for Cylindrical Vessel
Authors: Sui Yaguang , Zhang Dezhi , Chen Bo , Wang Zhao , Tang Shiying
Published: January 2017

With centrally loaded charges, the deformation of the cylindrical vessel is concentrated in the range of L/R = ±2 by the blast center. The reactive reinforcement method, which uses dispersive charges cooperating with vessels to control the concentrated charge, is presented in this study. The experimental research on this reactive reinforcement method is tested experimentally. Global and flakelike charges are selected as the inner and outer charges, respectively. This method primarily focuses on synchronizations, especially the detonation synchronization of such inner and outer charges. A detonation system is designed, and central and multipoint detonation techniques are used to control the synchronization. Three experiments are performed, of which two are advanced studies. The third is an experimental research on the method. Results show that the max time difference of the detonation system is 1 μs, suggesting good synchronization performance. The strain of the vessel is reduced by about 71.4% using the reinforcement method. This study provides a reference for the reinforcement method in practical applications.
Comprehensive Analysis for Influence of Controllable Damper Time Delay on Semi-Active Suspension Control Strategies
Authors: Qin Yechen , Zhao Feng , Wang Zhenfeng , Gu Liang , Dong Mingming
Published: January 2017

This paper presents a comprehensive comparison and analysis for the effect of time delay on the five most representative semi-active suspension control strategies, and refers to four unsolved problems related to semi-active suspension performance and delay mechanism that existed. Dynamic characteristics of a commercially available continuous damping control (CDC) damper were first studied, and a material test system (MTS) load frame was used to depict the velocity-force map for a CDC damper. Both inverse and boundary models were developed to determine dynamic characteristics of the damper. In addition, in order for an improper damper delay of the form t+τ to be corrected, a delay mechanism of controllable damper was discussed in detail. Numerical simulation for five control strategies, i.e., modified skyhook control SC, hybrid control (HC), COC, model reference sliding mode control (MRSMC), and integrated error neuro control (IENC), with three different time delays: 5 ms, 10 ms, and 15 ms was performed. Simulation results displayed that by changing control weights/variables, performance of all five control strategies varied from being ride comfort oriented to being road handling oriented. Furthermore, increase in delay time resulted in deterioration of both ride comfort and road handling. Specifically, ride comfort was affected more than road handling. The answers to all four questions were finally provided according to simulation results.
Loads and Acoustics Prediction on Deployed Weapons Bay Doors
Authors: Sheta Essam F. , Harris Robert E. , George Benjamin , Ukeiley Lawrence , Luke Edward
Published: January 2017

Unsteady separated flow from deployed weapons bay doors can interact with the highly unsteady flow in the open bay cavity, which is known to exhibit strong acoustic content and could lead to fluid-resonance and high-intensity acoustic noise. The culmination of these unique flow physics can potentially excite structural modes of the doors, aircraft surfaces, or externally carried munitions and fuel tanks and can ultimately lead to aeroelastic instabilities, such as buffet, flutter, limit-cycle oscillations, or fatigue-induced failures. A hybrid Reynolds-averaged Navier–Stokes large eddy simulation (RANS/LES) method with low-dissipation schemes is developed to improve flow and acoustics predictive capabilities for supersonic weapons bays. Computational simulations are conducted for a weapons cavity with different deployed bay doors configurations, including the effect of dynamically moving doors, to assess the tonal content and unsteady aerodynamic loads on the doors. Wind tunnel testing is also carried out to provide unsteady experimental data for use in validating the high-fidelity simulation capability. The simulation results in terms of unsteady pressure, velocity fluctuations, and pressure resonant frequencies are computed and presented. The results suggest that the deployed doors energize the shear layer and cause it to go deeper into the cavity and produce higher unsteady fluctuations on the weapons cavity floor and aft wall. The deployed doors also cause a shift in the dominant resonant modes.
Aggressive Spiral Toolpaths for Pocket Machining Based on Medial Axis Transformation
Authors: Huang Nuodi , Lynn Roby , Kurfess Thomas
Published: January 2017

High-speed machine tools typically provide high spindle speeds and feedrates to achieve an effective material removal rate (MRR). However, it is not possible to realize the full extent of their high-speed capabilities due to the sharp corners of toolpaths which are introduced by conventional machining strategies, such as contour- and direction-parallel toolpaths. To address this limitation, spiral toolpaths that can reduce the magnitude of sudden direction changes have been developed in previous researches. Nevertheless, for some pockets, the average radial cutting width is significantly decreased while the total length of the toolpath is significantly increased as compared to contour- and direction-parallel toolpath. In this situation, spiral toolpath may take more machining time. To overcome these drawbacks, an aggressive spiral toolpath generation method based on the medial axis (MA) transformation is proposed in machining pocket without islands inside, which refers to no additional material inside the counter. The salient feature of this work is that it integrates the advantages of both conventional contour-parallel machining strategy and the existing spiral toolpath machining strategy. The cutting width at each MA point is determined based on the diameter of the locally inscribed circle (LIC) of the MA point and the topological structure of MA. A distance-constrained contour determination algorithm is utilized to calculate the toolpath for each pass. Finally, a circular arc transition strategy is used to transform all the isolated passes into a spiral toolpath. Experiments are conducted to show the effectiveness of the proposed method.
Integrated Three-Dimensional Thermohydrodynamic Analysis of Turbocharger Rotor and Semifloating Ring Bearings
Authors: Liang Feng , Li Yajing , Zhou Ming , Xu Quanyong , Du Farong
Published: January 2017

The mechanical performances of turbocharger rotor bearings system are strongly coupled with the thermal effects of lubrication. This paper built an integrated three-dimensional thermohydrodynamic model for the rotor and semifloating ring bearings. The thermal viscosity and non-Newtonian effects of lubricant oil are involved. Three experimental cases with different oil supply temperatures and pressures are conducted to validate the numerical results. The prediction coincides well with the measured results. Subsynchronous responses jumping between the conical and cylindrical mode shapes happens. The thermal results show that the heat conduction and expansion of the solid parts can affect the temperature fields and clearances of the oil films. Furthermore, for the bearings with axial grooves, the underdeveloped thermal boundary layers exist in the inner film at high rotational speed. The complexity and heterogeneity of the oil film temperature and viscosity reveal the essentiality and significance of the three-dimensional thermohydrodynamic analysis.
Parameterization of Battery Electrothermal Models Coupled With Finite Element Flow Models for Cooling
Authors: Samad Nassim A. , Wang Boyun , Siegel Jason B. , Stefanopoulou Anna G.
Published: January 2017

Developing and parameterizing models that accurately predict the battery voltage and temperature in a vehicle battery pack are challenging due to the complex geometries of the airflow that influence the convective heat transfer. This paper addresses the difficulty in parameterizing low-order models which rely on coupling with finite element simulations. First, we propose a methodology to couple the parameterization of an equivalent circuit model (ECM) for both the electrical and thermal battery behavior with a finite element model (FEM) for the parameterization of the convective cooling of the airflow. In air-cooled battery packs with complex geometries and cooling channels, an FEM can provide the physics basis for the parameterization of the ECM that might have different convective coefficients between the cells depending on the airflow patterns. The second major contribution of this work includes validation of the ECM against the data collected from a three-cell fixture that emulates a segment of the pack with relevant cooling conditions for a hybrid vehicle. The validation is performed using an array of thin film temperature sensors covering the surface of the cell. Experiments with pulsing currents and drive cycles are used for validation over a wide range of operating conditions (ambient temperature, state of charge, current amplitude, and pulse width).
Self-Tuning Robust Fuzzy Controller Design Based on Multi-Objective Particle Swarm Optimization Adaptation Mechanism
Authors: Costa Edson B. M. , Serra Ginalber L. O.
Published: January 2017

In this paper, an adaptive fuzzy controller design methodology via multi-objective particle swarm optimization (MOPSO) based on robust stability criterion is proposed. The plant to be controlled is modeled from its input–output experimental data considering a Takagi–Sugeno (TS) fuzzy nonlinear autoregressive with exogenous input model, by using the fuzzy C-means clustering algorithm (antecedent parameters estimation) and the weighted recursive least squares (WRLS) algorithm (consequent parameters estimation). An adaptation mechanism as MOPSO problem for online tuning of a fuzzy model based digital proportional-integral-derivative (PID) controller parameters, based on the gain and phase margins specifications, is formulated. Experimental results for adaptive fuzzy digital PID control of a thermal plant with time-varying delay are presented to illustrate the efficiency and applicability of the proposed methodology.
Numerical Simulation on Concrete Median Barrier for Reducing Concrete Fragment Under Harsh Impact Loading of a 25-ton Truck
Authors: Lee Jaeha , Zi Goangseup , Lee Ilkeun , Jeong Yoseok , Kim Kyeongjin , Kim WooSeok
Published: January 2017

Recently, there was a collision accident involving vehicle–concrete median barrier in South Korea, and unfortunately, passengers on the opposite direction road were killed by the flying broken pieces of concrete generated by the collision. Primarily after this accident, we felt the need for developing an improved concrete median barrier up to level of SB6 impact severity in order to minimize the amount of broken pieces of concrete and any possibility of traffic accident casualty under the impact loading of truck. Accordingly, in this study, several designs of concrete median barriers have been examined, and a preliminary study has been conducted for developing and verifying appropriate collision model. First, type of vehicle was selected based on impact analysis on rigid wall. Then, the effects of element size and other key parameters on the capacity of the concrete median barrier under impact were studied. It was found that the key parameters for controlling behaviors of the median barrier under impact loading were contact option, threshold value, and mesh and boundary conditions. Furthermore, as a parametric study, effect of geometry and amount of wire-mesh or steel rebar in concrete median barrier on impact resistances of median barrier for reducing the collision debris were investigated. The amount of volume loss after the collision of truck was compared for various reinforcement ratios.
Phase Angles of the Vibrations and Hydrodynamic Forces of the Flexible Risers Undergoing Vortex-Induced Vibration
Authors: Song Leijian , Fu Shixiao , Ren Tie , Lu Ziqi
Published: January 2017

This paper investigates the phase angles of the vibrations and hydrodynamic forces by the model testing of a flexible riser's vortex-induced vibration (VIV) under uniform flow. The VIV displacement of the riser is derived from the measured strains in the cross-flow (CF) and inline (IL) directions. Then, the hydrodynamic forces are obtained by the dynamic equation of an Euler–Bernoulli beam based on the results of VIV displacement. The characteristics of the phase angle of displacement and the hydrodynamic forces are analyzed. The results show that the phase angles of displacement and the hydrodynamic forces are almost identical at different cross sections of the riser under uniform flow. Moreover, within two adjacent vibration nodes in IL direction, the phase angle almost kept constant, while had a 180 deg change at the two sides of each vibration node. When the reduced velocity varies from 5.25 to 7.5, the phase angles of displacement derived from the flexible riser's VIV are 45 deg larger than those from the rigid cylinder's self-excited vibration.
Dynamic Responses of Jacket-Type Offshore Wind Turbines Using Decoupled and Coupled Models
Authors: Chen Ong Muk , Bachynski Erin E. , David Økland Ole
Published: January 2017

This paper presents numerical studies of the dynamic responses of two jacket-type offshore wind turbines (OWTs) using both decoupled and coupled models. The investigated structures are the OC4 (Offshore Code Comparison Collaboration Continuation) jacket foundation and a full-lattice support structure presented by Long et al., 2012, “Lattice Towers for Bottom-Fixed Offshore Wind Turbines in the Ultimate Limit State: Variation of Some Geo metric Parameters,” ASME J. Offshore Mech. Arct. Eng., 134(2), p. 021202. Both structures support the NREL 5-MW wind turbine. Different operational wind and wave loadings at an offshore site with relatively high soil stiffness are investigated. In the decoupled (hydroelastic) model, the thrust and torque from an isolated rotor model were used as wind loads on the decoupled model together with a linear aerodynamic damper. The coupled model is a hydro-servo-aero-elastic representation of the system. The objective of this study is to evaluate the applicability of the computationally efficient linear decoupled model by comparing with the results obtained from the nonlinear coupled model. Good agreement was obtained in the eigen-frequency analysis, decay tests, and wave-only simulations. It was also found that, by applying the thrust force from an isolated rotor model in combination with linear damping, reasonable agreement could be obtained between the decoupled and coupled models in combined wind and wave simulations.
Static Characteristics of Journal Bearings With Square Dimples
Authors: Yamada Hiroyuki , Taura Hiroo , Kaneko Satoru
Published: January 2017

Surface texturing is a technique for improving frictional and hydrodynamic performances of journal bearings because microtextures can serve as reservoirs for oil or traps for debris and may also generate hydrodynamic pressure. Over the past two decades, many researchers have experimentally demonstrated that texturing of various tribological elements can reduce friction force and wear, contributing to improvement of lubrication performance. Some numerical studies have examined the hydrodynamic lubrication conditions and reported that surface texturing affects the static characteristics of journal bearings, such as their load carrying capacity and friction torque. However, the validity of these numerical models has not been confirmed because of a lack of experimental studies. This study proposes a numerical model that includes both inertial effects and energy loss at the edges of dimples on the surface of a journal bearing in order to investigate the bearing's static characteristics. Experimental verification of journal bearings is also conducted with a uniform square-dimple pattern on their full-bearing surface. The results obtained by the model agree well with those of experiment, confirming the model's validity. These results show that under the same operating conditions, textured bearings yield a higher eccentricity ratio and lower attitude angle than the conventional ones with a smooth surface. This tendency becomes more marked for high Reynolds number operating conditions and for textured bearings with a large number of dimples.
Wear Modeling Revisited Using Electrical Analogy
Authors: Hanief M. , Wani M. F.
Published: January 2017

Electrical analogy has been used extensively in modeling various mechanical systems such as thermal, hydraulic, and other dynamic systems. However, wear modeling of a tribosystem using electrical analogy has not been reported so far. In this paper, an equivalent electrical analogous system is proposed to represent the wear process. An analogous circuit is developed by mapping the wear process parameters to that of the electrical parameters. The circuit, thus, developed is solved by conventional electrical circuit theory. The material properties and operating conditions are taken into account by model parameters. Accordingly, a model equation in terms of model parameters is developed to represent the wear rate. It is also demonstrated how this methodology can be used to take various system parameters into account by incorporating the equivalent resistance of the parameters. The nonlinear model parameters are evaluated by Gauss–Newton (GN) algorithm. The proposed model is validated by using experimental data. A comparison of the proposed model with the experimental results, based on statistical methods: coefficient of determination (R2), mean-square-error (MSE) and mean absolute percentage error (MAPE), indicates that the model is competent to predict the wear with a high degree of accuracy.
An Outcrossing Rate Model and Its Efficient Calculation for Time-Dependent System Reliability Analysis
Authors: Jiang C. , Wei X. P. , Huang Z. L. , Liu J.
Published: January 2017

Time-dependent reliability problems widely appear in the engineering practice when the material properties of the structure deteriorate in time or random loading modeled as random processes is involved. Among existing methods to the time-dependent reliability problems, the most dominating one is the outcrossing rate method. This paper presents an outcrossing rate model and its efficient calculation approach for system problems, and based on the presented model, a time-dependent system reliability analysis method is proposed. The main idea of the method is to transform the evaluation of the system outcrossing rates into the calculation of a time-invariant system reliability. Three numerical examples are used to demonstrate the effectiveness of the proposed method.
Optimized Finite Element Method for Acoustic Scattering Analysis With Application to Head-Related Transfer Function Estimation
Authors: Farahikia Mahdi , Su Quang T.
Published: January 2017

Obtaining head-related transfer functions (HRTFs) is a challenging task, in spite of its importance in localizing sound in a three-dimensional (3D) environment or improving the performance of hearing aids, among their various applications. In this paper, an optimized finite element method through adaptive dimension size based on wavelength (frequency) for acoustic scattering analyses using ansys is presented. Initial investigation of the validity of our method is conducted by simulating scattered sound field for a solid sphere exposed to a far-field plane sound wave at 100 (equally spaced in logarithmic scale) frequencies between 20 and 20 kHz. Comparison of the equivalent HRTF results between the two methods shows a maximum deviation of less than 0.6 dB between our method and the analytical solution depending on the angle of rotation of the sphere with respect to sound source.
Design, Modeling, and Control of a Portable Leg Rehabilitation System
Authors: Goher Khaled M. , Fadlallah Sulaiman O.
Published: January 2017

In this work, a novel design of a portable leg rehabilitation system (PLRS) is presented. The main purpose of this paper is to provide a portable system, which allows patients with lower-limb disabilities to perform leg and foot rehabilitation exercises anywhere without any embarrassment compared to other devices that lack the portability feature. The model of the system is identified by inverse kinematics and dynamics analysis. In kinematics analysis, the pattern of motion of both leg and foot holders for different modes of operation has been investigated. The system is modeled by applying Lagrangian dynamics approach. The mathematical model derived considers calf and foot masses and moment of inertias as important parameters. Therefore, a gait analysis study is conducted to calculate the required parameters to simulate the model. Proportional derivative (PD) controller and proportional-integral-derivative (PID) controller are applied to the model and compared. The PID controller optimized by hybrid spiral-dynamics bacteria-chemotaxis (HSDBC) algorithm provides the best response with a reasonable settling time and minimum overshot. The robustness of the HSDBC–PID controller is tested by applying disturbance force with various amplitudes. A setup is built for the system experimental validation where the system mathematical model is compare with the estimated model using system identification (SI) toolbox. A significant difference is observed between both models when applying the obtained HSDBC–PID controller for the mathematical model. The results of this experiment are used to update the controller parameters of the HSDBC-optimized PID.
Tick surveillance in two southeastern provinces, including three metropolitan areas, of the Republic of Korea during 2014
Authors: Johnson Jaree L. , Kim Heung-chul , Coburn Jordan M. , Chong Sung-tae , Chang Nicholas W. , Robbins Richard George , Klein Terry A.
Published: January 2017

Tick-borne disease surveillance was conducted from March–October 2014 in two southeastern provinces, including three metropolitan areas, in the Republic of Korea (ROK). Three general habitats were surveyed: Grasses (grasses and herbaceous and crawling vegetation), Forests (pine, larch, deciduous, and mixed), and Forests+Grasses. A total of 40,048 ticks (1,480 adults; 24,201 nymphs; 14,367 larvae) belonging to three genera and six species were collected. Haemaphysalis longicornis (84.25%; 33,741) was the most commonly collected tick, followed by Haemaphysalis flava (14.52%; 5,816), Ixodes nipponensis (1.09%; 436), Amblyomma testudinarium (0.07%; 27), Haemaphysalis phasiana (0.06%; 23), and Ixodes turdus (0.01%; 5). Overall, adult ticks accounted for only 3.70% of all ticks collected, while nymphs and larvae accounted for 60.43% and 35.87%, respectively. The proportion of H. longicornis nymphs was highest beginning in March (99.51%), slowly declined through July (82.01%) and then rapidly declined to a low in October (6.45%). Large increases in the proportion of H. longicornis larvae were observed in August (42.05%), September (84.19%) and October (93.55%) following increased numbers of adults collected in June (4.20%), July (17.99%) and August (9.79%). Haemaphysalis flava adults and nymphs were commonly collected from April–May and October, while larvae were first collected from July, with peak numbers collected in August and low numbers collected during September–October. The proportion of I. nipponensis adults was highest in March (75.34%), declined to a low in July (0%), and then increased in September (60.00%) and October (90.32%). Larvae were collected only in August–September and accounted for 64.29% and 20.00% of all I. nipponensis collected during those months. Similar proportions of males and females of H. flava (51.47% and 48.53%, respectively) were collected from all habitats, while significantly more I. nipponensis males (62.20%) were collected than females (37.80%). Conversely, the proportion of H. longicornis females (80.00%) collected was significantly higher than for males (20.00%). Overall, the mean number of ticks collected/hr of collection for all habitats was 156.06/hr of collection. Similar numbers were collected/hr for Forests (172.61) and Grasses (168.64), while lower numbers were collected/hr for Forests+Grasses (128.12).
Chemical discrimination of pesticide-treated grapes by lizards (Gallotia galloti palmae, Fam. Lacertidae)
Authors: Yanes-Marichal Nieves Rosa , Francisco-Sánchez Angel Fermín , Molina-Borja Miguel
Published: January 2017

Lizards from the Canary Islands may act as pests of several cultivated plants. As a case in point, vineyard farmers often complain about the lizards’ impact on grapes. Though no specific pesticide is used for lizards, several pesticides are used in vineyards to control for insects, fungi, etc. We therefore tested whether lizards (Gallotia galloti palmae) could detect and discriminate pesticide-treated from untreated grapes. To answer this question, we performed experiments with adults of both sexes obtained from three localities in La Palma Island. Two of them were a vineyard and a banana plantation that had been treated with pesticides and the other one was in a natural (untreated) site. In the laboratory, lizards were offered simultaneously one untreated (water sprayed) and one treated (with Folithion 50 LE, diluted to 0.1%) grape placed on small plates. The behaviour of the lizards towards the fruits was filmed and subsequently quantified by means of their tongue-flick, licks or bite rates to each of the grapes. Results showed that only lizards from the natural (untreated) site clearly differentiated the two types of grapes, performing significantly more tongue-flicks, licks and bites to the untreated than to the pesticide-treated grapes. Lizards captured at the other two sites (cultivated fields with pesticide treatment), did not show a significantly different response to the two types of grapes. These results suggest that lizards living in or near cultivated fields may be habituated to pesticide-treated food and, therefore, do not clearly discriminate treated from untreated food items. However, another possibility is that natural selection (or maybe resistance) could be responsible by these individuals in the populations showing this kind of pesticide insensitiveness.
An inequality for longitudinal and transverse wave attenuation coefficients
Authors: Norris Andrew N.
Published: January 2017

Total absorption, defined as the net flux of energy out of a bounded region averaged over one cycle for time harmonic motion, must be non-negative when there are no sources of energy within the region. This passivity condition places constraints on the non-dimensional absorption coefficients of longitudinal and transverse waves, γL and γT, in isotropic linearly viscoelastic materials. Typically, γL, γT are small, in which case the constraints imply that coefficients of attenuation per unit length, αL, αT, must satisfy the inequality αL/αT≥4cT3/3cL3 where cL, cT are the wave speeds. This inequality, which as far as the author is aware, has not been presented before, provides a relative bound on wave speed in terms of attenuation, or vice versa. It also serves as a check on the consistency of ultrasonic measurements from the literature, with most but not all of the data considered passing the positive absorption test.
Single-shot real-time video recording of a photonic Mach cone induced by a scattered light pulse
Authors: Liang Jinyang , Ma Cheng , Zhu Liren , Chen Yujia , Gao Liang , Wang Lihong V.
Published: January 2017

Lossless-encoding compressed ultrafast photography captures a movie of a photonic Mach cone at 100 billion frames per second.
Activation of mosquito complement antiplasmodial response requires cellular immunity
Authors: Castillo Julio César , Ferreira Ana Beatriz Barletta , Trisnadi Nathanie , Barillas-Mury Carolina
Published: January 2017

In malaria-infected mosquitoes, microvesicles from hemocytes activate complement to fight infection.
Proteomic and Mutant Analysis of the CO
2
Concentrating Mechanism of Hydrothermal Vent Chemolithoautotroph Thiomicrospira crunogena
Authors: Mangiapia Mary ,   USF MCB4404L, Brown Terry-René W. , Chaput Dale , Haller Edward , Harmer Tara L. , Hashemy Zahra , Keeley Ryan , Leonard Juliana , Mancera Paola , Nicholson David , Stevens Stanley , Wanjugi Pauline , Zabinski Tania , Pan Chongle , Scott Kathleen M.
Published: January 2017

Many autotrophic microorganisms are likely to adapt to scarcity in dissolved inorganic carbon (DIC; CO
2
+ HCO
3
−
+ CO
3
2−
) with CO
2
concentrating mechanisms (CCM) that actively transport DIC across the cell membrane to facilitate carbon fixation. Surprisingly, DIC transport has been well studied among cyanobacteria and microalgae only. The deep-sea vent gammaproteobacterial chemolithoautotroph
Thiomicrospira crunogena
has a low-DIC inducible CCM, though the mechanism for uptake is unclear, as homologs to cyanobacterial transporters are absent. To identify the components of this CCM, proteomes of
T. crunogena
cultivated under low- and high-DIC conditions were compared. Fourteen proteins, including those comprising carboxysomes, were at least 4-fold more abundant under low-DIC conditions. One of these proteins was encoded by
Tcr_0854
; strains carrying mutated copies of this gene, as well as the adjacent
Tcr_0853
, required elevated DIC for growth. Strains carrying mutated copies of
Tcr_0853
and
Tcr_0854
overexpressed carboxysomes and had diminished ability to accumulate intracellular DIC. Based on reverse transcription (RT)-PCR,
Tcr_0853
and
Tcr_0854
were cotranscribed and upregulated under low-DIC conditions. The
Tcr_0853
-encoded protein was predicted to have 13 transmembrane helices. Given the mutant phenotypes described above,
Tcr_0853
and
Tcr_0854
may encode a two-subunit DIC transporter that belongs to a previously undescribed transporter family, though it is widespread among autotrophs from multiple phyla.

IMPORTANCE
DIC uptake and fixation by autotrophs are the primary input of inorganic carbon into the biosphere. The mechanism for dissolved inorganic carbon uptake has been characterized only for cyanobacteria despite the importance of DIC uptake by autotrophic microorganisms from many phyla among the
Bacteria
and
Archaea
. In this work, proteins necessary for dissolved inorganic carbon utilization in the deep-sea vent chemolithoautotroph
T. crunogena
were identified, and two of these may be able to form a novel transporter. Homologs of these proteins are present in 14 phyla in
Bacteria
and also in one phylum of
Archaea
, the
Euryarchaeota
. Many organisms carrying these homologs are autotrophs, suggesting a role in facilitating dissolved inorganic carbon uptake and fixation well beyond the genus
Thiomicrospira
.
Surgical resection of a rare cutaneous manifestation ofScedosporium apiospermumin a patient who underwent renal transplant
Authors: Stoneham A C S , Stoneham S E , Wyllie S A , Pandya A N
Published: January 2017

A man aged 47 years who was immunosuppressed following renal transplantation for focal segmental glomerulosclerosis was referred to the Plastic Surgery team for management of a painful, chronic, granulomatous lesion of the right forearm. Serial ultrasound scans and MRI scans were not diagnostic, but microbiological specimens tested positive for the fungusScedosporium apiospermum. The renal transplant graft—which was failing—was removed, allowing him to cease immunosuppression. He then underwent a resection of the lesion and reconstruction with a split thickness skin graft. Analysis of the specimen revealed fibrosis, granulomatosis and a collection ofS. apiospermum. He was started on voriconazole which, in conjunction with his surgical resection, appears to have kept the disease at bay. With increasing numbers of solid organ transplants and improved survival, this case highlights the growing burden of rare, opportunistic infections, the difficulty in diagnosis and the need for specialist intervention.
An evaluation study of the Becton-Dickinson ProbeTec Qx (BDQx) Trichomonas vaginalis trichomoniasis molecular diagnostic test in two large, urban STD services
Authors: Tipple Craig , Rayment Michael , Mandalia Sundhiya , Walton Lisa , O'Neill Sinead , Murray John , O'Riordan Alan , Rebec Monica , Harrington Laura , Jones Rachael , Wilkinson Dawn
Published: January 2017

Objectives

The BASHH guidelines recommend molecular tests to aid diagnosis of Trichomonas vaginalis (TV) infection; however many clinics continue to use relatively insensitive techniques (pH, wet-prep microscopy (WPM) and culture). Our objectives were to establish a laboratory pathway for TV testing with the Becton-Dickinson Qx (BDQx) molecular assay, to determine TV prevalence and to identify variables associated with TV detection.

Methods

A prospective study of 901 women attending two urban sexual health services for STI testing was conducted. Women were offered TV BDQx testing in addition to standard of care. Data collected were demographics, symptoms, results of near-patient tests and BDQx results for TV, Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (GC). Women with any positive TV result were treated and followed up for test of cure (TOC).

Results

901 women had a TV BDQx test. 472 (53%) were white, 143 (16%) black and 499 (55%) were symptomatic. Infections detected by BDQx were: 11 TV (1.2%), three GC (0.3%) and 44 CT (4.9%). Of the 11 BDQx-detected TV infections, 8 (73%) were in patients of black ethnicity. Of these, four of seven cases (57%) were WPM-positive. All patients received treatment and nine of nine (100%) were BDQx-negative at TOC. In univariate analysis, only black ethnicity was associated with likelihood of a positive TV BDQx result (relative risk (RR) 10.2 (95% CI 2.15 to 48.4)).

Conclusions

The use of the BDQ enhanced detection of TV in asymptomatic and symptomatic populations. Cost-effective implementation of the test will rely on further work to reliably detect demographic and clinical variables that predict positivity.
Effects of exogenous vitamins A, C, and E and NADH supplementation on proliferation, cytokines release, and cell redox status of lymphocytes from healthy aged subjects
Authors: Bouamama Samia , Merzouk Hafida , Medjdoub Amel , Merzouk-Saidi Amel , Merzouk Sid Ahmed
Published: January 2017

Aging is an inevitable biological event that is associated with immune alterations. These alterations are related to increased cellular oxidative stress and micronutrient deficiency. Antioxidant supplementation could improve these age-related abnormalities. The aim of this study was to determine in vitro effects of vitamin A, vitamin C, vitamin E, and nicotinamide adenine dinucleotide (NADH) on T cell proliferation, cytokine release, and cell redox status in the elderly compared with young adults. Peripheral blood lymphocytes were isolated using a density gradient of Histopaque. They were cultured in vitro and stimulated with concanavalin A in the presence or absence of vitamins. Cell proliferation was determined by conducting MTT assays, and based on interleukin-2 and interleukin-4 secretions. Cell oxidant/antioxidant balance was assessed by assaying reduced glutathione (GSH), malondialdehyde, carbonyl protein levels, and catalase activity. The present study demonstrated that T-lymphocyte proliferation was decreased with aging and was associated with cytokine secretion alterations, GSH depletion, and intracellular oxidative stress. In the elderly, vitamin C, vitamin E, and NADH significantly improved lymphocyte proliferation and mitigated cellular oxidative stress, whereas vitamin A did not affect cell proliferation or cell redox status. In conclusion, vitamin C, vitamin E, and NADH supplementation improved T-lymphocytes response in the elderly, and could contribute to the prevention of age-related immune alterations. Consumption of food items containing these vitamins is recommended, and further investigation is necessary to evaluate the effect of vitamin supplementation in vivo.
Influence of end effect on rock strength in true triaxial compression test
Authors: Xu Y.H. , Cai M. , Zhang X.W. , Feng X.T.
Published: January 2017

The influence of the end effect on rock strength in true triaxial compression testing was studied using a numerical approach. The influence of the intermediate principal stress (σ2) on rock strength was isolated by using the two-dimensional Mohr–Coulomb failure criterion that depends only on the major principal stress (σ1) and minor principal stress (σ3). Thus, any enhancement to the rock strength with the increase of σ2can be attributed to the end effect. It was shown that the end effect can result in an apparent σ2effect, as long as the coefficient of friction (μ) at the rock specimen – steel platen contacts is not zero and the specimen in the σ2loading direction is squat. When the strengthening due to the increase of σ2predicted by a theoretical failure criterion was added to the strengthening due to the end effect, the results were in good agreement with the observed σ2effect from some previous laboratory tests, indicating that the observed σ2effect in true triaxial compression testing could be partially influenced by the end effect, particularly when σ3was low. It is suggested to decrease the end effect to a level where the apparent σ2effect is very small so that the obtained test results are more meaningful to characterize the actual σ2effect.
Integrated system of equations for estimating stem volume, density, and biomass for Australian redcedar (Toona ciliata) plantations
Authors: Calegario Natalino , Gregoire Timothy G. , da Silva Tatiane Antunes , Tomazello Filho Mario , Alves Joyce A.
Published: January 2017

A system of equations is proposed to assess the stem wood density variation of Toona ciliata M. Roem. growing in Brazilian plantations. As a taper function, a third-degree polynomial was fitted and the stem radius squared (r2), the dependent variable, was estimated as a function of diameter at breast height (dbh), total height (ht), and radius (r) at height (h). A nonlinear function was fitted to estimate wood density variation, having as the independent variable the ratio of r to h. The stem mass was estimated by integrating the product of stem volume and wood density. Stem measurements from a group of 72 trees of T. ciliata were used to fit the taper equation. A group of six trees was selected and a wood density database was created using X-ray technology. Both the taper and the nonlinear functions performed well in estimating the radius and the wood density. The within-tree wood density systematically increased from pith to bark and from the base to the top of the tree. With the density varying from base to top, the estimated mass of the stem, compared with the mass estimated using wood density value at dbh, had a bias of 4.2%. When the density variations from base to top and from pith to bark of the tree were considered, the estimated mass had a bias of 1.5%.
Counting curves on surfaces
Authors: Do Norman , Koyama Musashi A. , Mathews Daniel V.
Published: January 2017

We consider an elementary, and largely unexplored, combinatorial problem in low-dimensional topology: for a compact surface [Formula: see text], with a finite set of points [Formula: see text] fixed on its boundary, how many configurations of disjoint arcs are there on [Formula: see text] whose boundary is [Formula: see text]? We find that this enumerative problem, counting curves on surfaces, has a rich structure. We show that such curve counts obey an effective recursion, in the general spirit of topological recursion, and exhibit quasi-polynomial behavior. This “elementary curve-counting” is in fact related to a more advanced notion of “curve-counting” from algebraic geometry or symplectic geometry. The asymptotics of this enumerative problem are closely related to the asymptotics of volumes of moduli spaces of curves, and the quasi-polynomials governing the enumerative problem encode intersection numbers on moduli spaces. Among several other results, we show that generating functions and differential forms for these curve counts exhibit structure that is reminiscent of the mathematical physics of free energies, partition functions and quantum curves.
The subset of R3 not realizing metrics on the curve complex
Authors: Zhang Faze , Zou Yanqing
Published: January 2017

In [F. Zhang, R. Qiu and Y. Zou, The subset of [Formula: see text] realizing metrics on the curve complex, Topology Appl. 193 (2015) 259–269], they defined a subset [Formula: see text] of [Formula: see text] and a metric [Formula: see text] through each point of [Formula: see text] for the curve complex [Formula: see text]. For further understanding the curve complex, we concern the whole set [Formula: see text]. With adaption to the flow theory on torus, we prove that for any point of [Formula: see text], the [Formula: see text] is not a metric on [Formula: see text] or [Formula: see text]. This means that the [Formula: see text] is the maximal subset of [Formula: see text] realizing metrics on the curve complex.
JOINT IMPACTS OF THERAPY DURATION, DRUG EFFICACY AND TIME LAG IN IMMUNE EXPANSION ON IMMUNITY BOOSTING BY ANTIVIRAL THERAPY
Authors: SHU HONGYING , WANG LIN
Published: January 2017

Antiviral drug therapy that targets on boosting virus-specific immune response has become very promising in controlling the virus, especially when completely eradicating the virus from the host turns out to be difficult. Using a concrete viral infection model that incorporates the time lag needed for the expansion of immune cells, we numerically explored the joint impacts of the duration of therapy, the efficacy of the drugs and the time lag in immune expansion on immunity boosting for a single phase of therapy. Our findings reveal that a single phase of therapy can establish sustained immunity if the therapy is stopped in a suitable range of timing and large time lag in the expansion of immune cells and too strong or too weak therapy would lead to a failure in immunity boosting. Our findings may provide some insights on designing efficient and rational therapy strategies in boosting sustained immunity.
Spacetime algebra for the reformulation of fluid field equations
Authors: Demir Süleyman , Tanışlı Murat
Published: January 2017

In the light of the analogy between electromagnetism and fluid dynamics, the Maxwell-type equations of compressible fluids are reformulated on the basis of spacetime algebra. In this paper, it is proved that this algebra provides an efficient mathematical tool for describing fluid fields in a compact and elegant way. Moreover, the fluid wave equation in terms of potentials are derived in a form similar to electromagnetic and gravitational counterparts previously derived using spacetime algebra.
On ruled surface in 3-dimensional almost contact metric manifold
Authors: Karacan Murat Kemal , Yuksel Nural , Ikiz Hasibe
Published: January 2017

In this paper, we study ruled surface in 3-dimensional almost contact metric manifolds by using surface theory defined by Gök [Surfaces theory in contact geometry, PhD thesis (2010)]. We also studied the theory of curves using cross product defined by Camcı. In this study, we obtain the distribution parameters of the ruled surface and then some results and theorems are presented with special cases. Moreover, some relationships among asymptotic curve and striction line of the base curve of the ruled surface have been found.
Xylene-sensing of Fe2(MoO4)3 nanoplates prepared via a hydrothermal method
Authors: Xu Mengying , Lin Zhidong , Guo Wenying , Hong Yuyuan , Fu Ping , Chen Zhe , Tang Dingguo
Published: January 2017

Fe2(MoO4)3 nanoplates were prepared via a simple hydrothermal process. The average crystalline size of these nanoplates is 85.8[Formula: see text]nm. The sensor based on Fe2(MoO4)3 shows a high gas sensing performance to xylene. The response of Fe2(MoO4)3 sensor is 25.9–100[Formula: see text]ppm xylene at optimum operating temperature of 340[Formula: see text]C. The response and recovery times to 100[Formula: see text]ppm xylene are 4 and 10[Formula: see text]s, respectively. Furthermore, the Fe2(MoO4)3 sensor exhibits remarkable selectivity detection of xylene gas with negligible responses to toluene and benzene. Therefore, the Fe2(MoO4)3 is a promising material for the detection of xylene gas sensors.
Modeling of endoplasmic reticulum and plasma membrane Ca2+ uptake and release fluxes with excess buffer approximation (EBA) in fibroblast cell
Authors: Kotwani Mansha , Adlakha Neeru
Published: January 2017

Many cells use oscillations in calcium concentration to transmit messages. These oscillations largely depend on the influx of calcium into cytosol from endoplasmic reticulum (ER) and plasma membrane (PM) through various channels and pumps. To analyze the influence of transfer of calcium between different cellular compartments, we develop a mathematical model of calcium dynamics in fibroblast cell. The model involves three important physiological parameters [Formula: see text], and excess buffer approximation (EBA). Finite difference method has been employed to obtain the solution. A computer program has been developed in MATLAB 7.10 for the entire problem and numerical results have been used to study the effects of buffers, ER and PM fluxes on spatial and temporal calcium patterns required by the cell to perform specific cell function.
User-centric distributed solutions for privacy-preserving analytics
Authors: Bestavros Azer , Lapets Andrei , Varia Mayank
Published: January 2017

How can cryptography empower users with sensitive data to access large-scale computing platforms in a privacy-preserving manner?
Patterns of Sociodemographic and Clinicopathologic Characteristics of Stages II and III Colorectal Cancer Patients by Age: Examining Potential Mechanisms of Young-Onset Disease
Authors: Murphy Caitlin C. , Sanoff Hanna K. , Stitzenberg Karyn B. , Baron John A. , Lund Jennifer L. , Sandler Robert S.
Published: January 2017

Background and Aims.As a first step toward understanding the increasing incidence of colorectal cancer (CRC) in younger (age < 50) populations, we examined demographic, clinicopathologic, and socioeconomic characteristics and treatment receipt in a population-based sample of patients newly diagnosed with stages II and III CRC.Methods.Patients were sampled from the National Cancer Institute’s Patterns of Care studies in 1990/91, 1995, 2000, 2005, and 2010 (n=6,862). Tumor characteristics and treatment data were obtained through medical record review and physician verification. We compared sociodemographic and clinicopathologic characteristics and treatment patterns of younger (age < 50) and older (age 50–69, age ≥ 70) CRC patients.Results.Younger patients were more likely to be black (13%) and Hispanic (15%) than patients aged 50–69 years (11% and 10%, resp.) and ≥70 years (7% each). A larger proportion of young white (41%) and Hispanic (33%) patients had rectal tumors, whereas tumors in the right colon were the most common in young black patients (39%). The majority of younger patients received chemotherapy and radiation therapy, although receipt of microsatellite instability testing was suboptimal (27%).Conclusion.Characteristics of patients diagnosed with young-onset CRC differ considerably by race/ethnicity, with a higher proportion of black and Hispanic patients diagnosed at the age of < 50 years.