bluuebunny/crossref_metadata_2025 huggingface dataset:
An effective method of wastewater treatment using titanium salt and a coagulant aid of chitosan
Authors: Okour Yousef H. , Ahmed Sameh S.
Published: October 2018

Titanium (Ti) salt has been used in wastewater flocculation and significantly decreases the pH of wastewater which is not industrially preferable. Thus, this study aims to use a natural polymer, chitosan, with Ti salt to observe a significant impact on pH of Ti salt flocculation and significantly reduce the produced sludge volume. The impact of chitosan addition on Ti salt flocculation pH, Ti salt optimum dose, Ti sludge, turbidity and organic removal was investigated. The results showed that using an optimum dose of 25 mg/L of Ti salt, Ti salt flocculation pH sharply decreased to 3.20 with turbidity and organic removal reaching 80 and 70%, respectively. The addition of chitosan to the Ti salt is found to be very effective due to the ability of chitosan foils to bridge the neutralised wastewater particles. The use of low doses of Ti salt with chitosan had an impact on flocculation pH and resulted in 40% of Ti sludge reduction.
Validating a rapid assessment framework for screening surface water flood risk
Authors: Webber J.L. , Booth G. , Gunasekara R. , Fu G. , Butler D.
Published: October 2018

This research evaluates performance of a rapid assessment framework for screening surface water flood risk in urban catchments. Recent advances in modelling have developed fast and computationally efficient cellular automata frameworks which demonstrate promising utility for increasing available evidence to support surface water management, however, questions remain regarding trade‐offs between accuracy and speed for practical application. This study evaluates performance of a rapid assessment framework by comparing results with outputs from an industry standard hydrodynamic model using a case study of St Neots in Cambridgeshire, UK. Results from the case study show that the rapid assessment framework is able to identify and prioritise areas of flood risk and outputs flood depths which correlate above 97% with the industry standard approach. In theory, this finding supports a simplified representation of catchments using cellular automata, and in practice presents an opportunity to apply the framework to develop evidence to support detailed modelling.
Assessment of School Fatigue, Leisure Time and Social Relationships in a Group of Teenagers From Two High Schools in Suceava
Authors: Albu Adriana , Bădăluță Arina , Dima Florin
Published: October 2018

School programs are frequently too demanding, so there is a good chance of school failure and chronic fatigue. The study was carried out on a group of 211 students from two high schools in the city of Suceava. A questionnaire was used that attempted to quantify school fatigue, passive and active leisure time, and social relationships. Fatigue occurs as a result of exceeding the body's exercise capacity. The situation is difficult for teenagers who have to adapt to school demands but who are also vulnerable to excessive levels of effort. Passive rest is done through night and daytime sleep. Numerous daily activities are commonly associated with reduced hours of sleep. There are situations where relaxing activities such as watching television programs and using the computer can become tiring. A long time spent on the computer can be associated with restricting social relationships, a phenomenon that must be evaluated more closely. Such studies are essential for maintaining student wellbeing and for ensuring proper school performance.
The Starfish Terminator
Authors: Zeldovich Lina
Published: October 2018

Researchers looking to stop a voracious predator have built a lean, mean, starfish-killing machine, an autonomous underwater robot equipped with artificial intelligence software. The robot is built by researchers at the Institute for Future Environments at Queensland University of Technology in Brisbane, Australia. From early detection algorithm to the COTSBot today, which has a 99 percent accuracy rate, having done several hundred runs injecting many starfish, this article charts its development journey.
Vacuum Wars
Authors: Sukel Kayt
Published: October 2018

American consumers have used some variation of the basic design of the first electric vaccum launched in 1907, to sweep their carpets and hardwood floors ever since. Waves of innovation periodically swept the industry. Mass production and plastics turned this once-luxury item into a household necessity. Companies introduced accessories to clean upholstery and hard-to-reach crevices. But, by and large, it was a staid industry whose players fought for business through marketing rather than engineering. But over the past few years, an eruption of technological innovations have turned the industry on its head. This article takes a deeper dive into those technology advances.
Chain Reaction
Authors: Brown Alan S.
Published: October 2018

For 30 years, additive manufacturing has made all sorts of promises. Yet machines remained slow, materials expensive, and printers too inconsistent for critical parts. And additive was costly. Today, however, the technology is turning that past on its head. While additive manufacturing is usually the most expensive way to make any part, it makes economic sense for supply chains. Which is why manufacturers of everything from aircraft and rolling stock to appliances, industrial equipment, and medical devices are looking at 3-D supply chain solutions—as are the U.S. Marines and UPS. This special report looks at how additive manufacturing is disrupting business models and transforming supply chains.
Characterizing the Biomechanical Properties of the Pubovisceralis Muscle Using a Genetic Algorithm and the Finite Element Method
Authors: Silva Elisabete , Parente Marco , Brandão Sofia , Mascarenhas Teresa , Natal Jorge Renato
Published: October 2018

To better understand the disorders in the pelvic cavity associated with the pelvic floor muscles (PFM) using computational models, it is fundamental to identify the biomechanical properties of these muscles. For this purpose, we implemented an optimization scheme, involving a genetic algorithm (GA) and an inverse finite element analysis (FEA), in order to estimate the material properties of the pubovisceralis muscle (PVM). The datasets of five women were included in this noninvasive analysis. The numerical models of the PVM were built from static axial magnetic resonance (MR) images, and the hyperplastic Mooney–Rivlin constitutive model was used. The material parameters obtained were compared with the ones established through a similar optimization scheme, using Powell's algorithm. To validate the values of the material parameters that characterize the passive behavior of the PVM, the displacements obtained via the numerical models with both methods were compared with dynamic MR images acquired during Valsalva maneuver. The material parameters (c1 and c2) were higher for the GA than for Powell's algorithm, but when comparing the magnitude of the displacements in millimeter of the PVM, there was only a 5% difference, and 4% for the principal logarithmic strain. The GA allowed estimating the in vivo biomechanical properties of the PVM of different subjects, requiring a lower number of simulations when compared to Powell's algorithm.
How to Improve Remanufacturing?—A Systematic Analysis of Practices and Theories
Authors: Sakao Tomohiko , Sundin Erik
Published: October 2018

Remanufacturing has gained attention from industry, but the literature lacks the scientific comprehension to realize efficient remanufacturing. This hinders a company from commencing or improving remanufacturing efficiently. To fill this gap, the paper proposes a set of practical success factors for remanufacturing. To do so, it analyzes remanufacturing practices in industry through interviews with staff from remanufacturing companies with long experience. The practical success factors are found to be (1) addressing product and component value, (2) having a customer-oriented operation, (3) having an efficient core acquisition, (4) obtaining the correct information, and (5) having the right staff competence. Next, the paper further analyzes remanufacturing processes theoretically with both cause and effect analysis and means-ends analysis. Since the factors show that, among other things, the product/service system (PSS) is highly relevant to remanufacturing in multiple ways, theories on the PSS are partly utilized. As a result, the distinctive nature of remanufacturing underlying in the processes is found to have high variability, high uncertainty and, thus, also complexity. The obtained insights from practice and theory are found to support each other. In addition, a fishbone diagram for remanufacturing is proposed based on the analysis, including seven m's, adding two new m's (marketing and maintenance) on top of the traditional five m's (measurement, material, human, method, and machine) in order to improve customer value. The major contribution of the paper lies in its insights, which are grounded in both theory and practice.
Test Rig for Applied Experimental Investigations of the Thermal Contact Resistance at the Blade-Rotor-Connection in a Steam Turbine
Authors: Toebben Dennis , de Graaf Xavier E. R. , Luczynski Piotr , Wirsum Manfred , Mohr Wolfgang F. D. , Helbig Klaus
Published: October 2018

Recent studies have shown that in a prewarming, respectively, warm-keeping operation of a steam turbine, the blades and vanes transport most of the heat to the thick-walled casing and rotor. Thereby, a thermal bottle-neck arises at the connection between the blade root and the rotor. The thermal contact resistance (TCR) at these interfaces affects the temperature distribution and thus the thermal stresses in the rotor. The present paper introduces an experimental setup, which is designed to quantify the TCR at the blade-rotor-connection of a steam turbine. An uncertainty analysis is presented, which proves that the average measurement uncertainties are less than one percent. The experiments especially focus on the investigation of the contact pressure, which is a function of the rotational speed. Therefore, the results of several steady-state measurements under atmospheric and evacuated atmosphere using a high temperature-resistant chromium-molybdenum steel are presented. For the evaluation of the TCR, a numerical model of the specimen is developed in addition to a simplified 1D approach. The results show a significantly increasing TCR with decreasing contact pressure, respectively, rotational speed.
Wave-Based Modeling and Control of Flexible Structures
Authors: Curran Paul F.
Published: October 2018

The relatively new concept of wave-based control is extended to general, finite-dimensional, linear, time-invariant systems, with or without damping. The new models offer an explanation for how systems of springs and masses although lumped, and therefore, technically having no delay appear to have delay nonetheless. The principal contribution is a fairly systematic, multi-input multi-output, multi-objective control design methodology. The method yields controllers which in general deliver good closed-loop tracking, good disturbance rejection, and good stability robustness in the face of parameter uncertainty. In particular, but not exclusively, the method is applicable to the control of flexible structures as demonstrated by several examples including mitigation of sloshing of liquid-fuel in a simplified model of an upper-stage Vega rocket.
Operation of a Spark Ignition Engine With High Compression Ratio Using Biogas Blended With Natural Gas, Propane, and Hydrogen
Authors: Montoya Juan Pablo Gómez , Amell Andrés A. , Olsen Daniel B.
Published: October 2018

This research evaluated the operational conditions for a diesel engine with high compression ratio (CR) converted to spark ignition (SI), under stable combustion conditions close to the knocking threshold. The main fuel used in the engine was biogas, which was blended with natural gas, propane, and hydrogen. The engine limit to test the maximum output power was using the knocking threshold; just below the knocking threshold, the output power and generating efficiency are the highest for each blend. Leaner mixtures increased the engine knocking tendency because the required increase in the % throttle reduced the pressure drop at the inlet stroke and increased the mixture pressure at the end of the compression stroke, which finally reduced the ignition delay time of the end gas and increased the knocking tendency of the engine for all the blends. Therefore, the output power should be decreased to operate the engine below to the knocking threshold. Purified biogas achieved the highest output power and generating efficiency compared with the other blends and the original diesel operation; this blend was operated with five equivalence ratios. Purified biogas exhibits an optimal balance between knocking resistance, low heating value, flame speed, and energy density.
Effective Geometric Algorithms for Immersed Boundary Method Using Signed Distance Field
Authors: Zhang Chenguang , Wu Chunliang , Nandakumar Krishnaswamy
Published: October 2018

We present three algorithms for robust and efficient geometric calculations in the context of immersed boundary method (IBM), including classification of mesh cells as inside/outside of a closed surface, projection of points onto a surface, and accurate calculation of the solid volume fraction field created by a closed surface overlapping with a background Cartesian mesh. The algorithms use the signed distance field (SDF) to represent the surface and remove the intersection tests, which are usually required by other algorithms developed before, no matter the surface is described in analytic or discrete form. The errors of the algorithms are analyzed. We also develop an approximate method on efficient SDF field calculation for complex geometries. We demonstrate how the algorithms can be implemented within the framework of IBM with a volume-average discrete-forcing scheme and applied to simulate fluid–structure interaction problems.
Tribological Properties of Spark Plasma Sintered NiCr–Cr2AlC Composites at Elevated Temperature
Authors: Li Xinliang , Yin Hong , Li Yu-Feng
Published: October 2018

In this work, layered ternary Cr2AlC powders with high purity and a size of 0.5–1 μm were synthesized by solid-state reaction method. NiCr–Cr2AlC composites have been prepared by spark plasma sintering (SPS) process. The composites' tribological properties were evaluated against alumina ball under dry sliding condition from room temperature to 600 °C. Compared with unmodified NiCr alloy, Cr2AlC addition has an effect on reduction of friction coefficient of NiCr–Cr2AlC composites at the temperatures up to 400 °C. Especially, in comparison with NiCr alloy, the wear rates of NiCr–Cr2AlC composites significantly decrease from 10−4 mm3/(N·m) to 10−5–10−6 mm3/(N·m) from room temperature to 600 °C (except for 200 °C). The NiCr–20 wt % Cr2AlC composite exhibited excellent tribological properties with a friction coefficient of 0.3–0.4 and a wear rate of about 10−6 mm3/(N·m) from 400 °C to 600 °C. Through the analysis of scanning electron microscope (SEM) and X-ray photoelectron spectroscope (XPS), it is clarified that effective improvement of tribological properties of NiCr–Cr2AlC composites is attributed to a glaze layer consisting of NiO, Cr2O3, Al2O3, and NiCr2O4, which is formed by tribo-oxidation during wear process.
High-Temperature Wear Mechanisms of a Severely Plastic Deformed Al/Mg2Si Composite
Authors: Ebrahimi Mahsa , Zarei-Hanzaki Abbas , Shafieizad A. H. , Šlapáková Michaela , Teymoory Parya
Published: October 2018

The present work was primarily conducted to study the wear behavior of as-received and severely deformed Al-15%Mg2Si in situ composites. The severe plastic deformation was applied using accumulative back extrusion (ABE) technique (one and three passes). The continuous dynamic recrystallization (CDRX) was recognized as the main strain accommodation and grain refinement mechanism within aluminum matrix during ABE cycles. To investigate the wear properties of the processed material, the dry sliding wear tests were carried out on both the as-received and processed samples under normal load of 10 and 20 N at room temperature, 100 °C, and 200 °C. The results indicated a better wear resistance of processed specimens in comparison to the as-received ones at room temperature. In addition, the wear performance was improved as the ABE pass numbers increased. These were related to the presence of oxide tribolayer. At 100 °C, the as-received material exhibited a better wear performance compared to the processed material; this was attributed to the formation of a work-hardened layer on the worn surface. At 200 °C, both the as-received and processed composites experienced a severe wear condition. In general, elevating the temperature changed the dominant wear mechanism from oxidation and delamination at room temperature to severe adhesion and plastic deformation at 200 °C.
Theoretical and Experimental Investigation of Two-to-One Internal Resonance in MEMS Arch Resonators
Authors: Alfosail Feras K. , Hajjaj Amal Z. , Younis Mohammad I.
Published: October 2018

We investigate theoretically and experimentally the two-to-one internal resonance in micromachined arch beams, which are electrothermally tuned and electrostatically driven. By applying an electrothermal voltage across the arch, the ratio between its first two symmetric modes is tuned to two. We model the nonlinear response of the arch beam during the two-to-one internal resonance using the multiple scales perturbation method. The perturbation solution is expanded up to three orders considering the influence of the quadratic nonlinearities, cubic nonlinearities, and the two simultaneous excitations at higher AC voltages. The perturbation solutions are compared to those obtained from a multimode Galerkin procedure and to experimental data based on deliberately fabricated Silicon arch beam. Good agreement is found among the results. Results indicate that the system exhibits different types of bifurcations, such as saddle node and Hopf bifurcations, which can lead to quasi-periodic and potentially chaotic motions.
Triangular Mesh and Boundary Representation Combined Approach for 3D CAD Lightweight Representation for Collaborative Product Development
Authors: Nguyen Cong Hong Phong , Choi Young
Published: October 2018

The lightweight representation of three-dimensional computer-aided design (3D CAD) models has drawn much attention from researchers as its usefulness in collaborative product development is vast. Existing approaches are mostly based on feature depression or mesh-based simplification. In this article, a new approach for 3D CAD lightweight representation based on combining triangular mesh representation and boundary representation (B-rep) is proposed. The corresponding data structure as well as the conversion method from original data given in B-rep was developed. Considered as an essential application in collaborative product development, a case study on the visualization process of large-scale assembly models represented in the proposed lightweight representation was also conducted. The validation of the approach was performed via experiments with 3D CAD models in SAT format and by benchmarking with the conventional all-faceted approach with the same level of mesh resolution.
An Underactuated PASA Finger Capable of Perfectly Linear Motion With Compensatory Displacement
Authors: Zheng Eric , Zhang Wenzeng
Published: October 2018

This paper presents a novel design for a robotic end effector. In particular, the design features a multifingered underactuated gripper capable of performing parallel and self-adaptive (PASA) grasping. The unique use of an eccentric cam fixed to a modified four-bar linkage mechanism allows the finger to compensate for the typical gap distance found during parallel pinching, improving the ability to grasp objects against surfaces and in tight spaces. A static analysis is performed on the design to determine the equilibrium conditions necessary for a successful grasp using this design in both the PASA modes. The mechanics of a four-bar mechanism are used to determine the grasp velocity and positioning of the hand in both grasp modes. Experimental results with a finger prototype confirm the desired closing trajectory.
A Computational Geometric Approach for Motion Generation of Spatial Linkages With Sphere and Plane Constraints
Authors: Li Xiangyun , Ge Q. J. , Gao Feng
Published: October 2018

This paper studies the problem of spatial linkage synthesis for motion generation from the perspective of extracting geometric constraints from a set of specified spatial displacements. In previous work, we have developed a computational geometric framework for integrated type and dimensional synthesis of planar and spherical linkages, the main feature of which is to extract the mechanically realizable geometric constraints from task positions, and thus reduce the motion synthesis problem to that of identifying kinematic dyads and triads associated with the resulting geometric constraints. The proposed approach herein extends this data-driven paradigm to spatial cases, with the focus on acquiring the point-on-a-sphere and point-on-a-plane geometric constraints which are associated with those spatial kinematic chains commonly encountered in spatial mechanism design. Using the theory of kinematic mapping and dual quaternions, we develop a unified version of design equations that represents both types of geometric constraints, and present a simple and efficient algorithm for uncovering them from the given motion.
A Numerical Simulation to the Influence of Unsteady Strain Flow on Twin Premixed Flames
Authors: Al-Malki Faisal
Published: October 2018

The aim of this paper was to examine the response of twin premixed flames formed in a counterflow configuration to the presence of an unsteady straining flow. We began by describing the problem mathematically using the thermodiffusive model with constant density and then adopted a finite elements approach to solve the problem numerically. The study has shown that the role of flow on flame propagation is determined by three main parameters, namely, flow amplitude A, strain rate ε, and fuel Lewis number LeF. For LeF ≥ 1, the flow is seen to promote flame extinction, while LeF < 1 the flow clearly enhances the flame reactivity. Qualitatively, it has been shown that for LeF = 1, there exists a critical value of A (that varies with ε) below which the reactivity decreases monotonically with A. For small LeF < 1, on the other hand, the reactivity was seen to increase with A. For LeF > 1, however, a nonmonotonic dependence, especially for small ε, is predicted.
Heat Transfer Investigation of a Tube Partially Wrapped by Metal Porous Layer as a Potential Novel Tube for Air Cooled Heat Exchangers
Authors: Mohammadpour-Ghadikolaie M. , Saffar-Avval M. , Mansoori Z. , Alvandifar N. , Rahmati N.
Published: October 2018

Laminar forced convection heat transfer from a constant temperature tube wrapped fully or partially by a metal porous layer and subjected to a uniform air cross-flow is studied numerically. The main aim of this study is to consider the thermal performance of some innovative arrangements in which only certain parts of the tube are covered by metal foam. The combination of Navier–Stokes and Darcy–Brinkman–Forchheimer equations is applied to evaluate the flow field. Governing equations are solved using the finite volume SIMPLEC algorithm and the effects of key parameters such as Reynolds number, metal foam thermophysical properties, and porous layer thickness on the Nusselt number are investigated. The results show that using a tube which is fully wrapped by an external porous layer with high thermal conductivity, high Darcy number, and low drag coefficient, can provide a high heat transfer rate in the high Reynolds number laminar flow, increasing the Nusselt number almost as high as 16 times compared to a bare tube. The most important result of thisstudy is that by using some novel arrangements in which the tube is partially covered by the foam layer, the heat transfer rate can be increased at least 20% in comparison to the fully wrapped tube, while the weight and material usage can be considerably reduced.
Heat and Momentum Transfer Analogies in Laminar Flow
Authors: Gancarczyk Anna , Iwaniszyn Marzena , Jodłowski Przemysław J. , Piątek Marcin , Korpyś Mateusz , Sindera Katarzyna , Kołodziej Andrzej
Published: October 2018

In this paper, we briefly present the heat/momentum transfer analogies of Reynolds and the followers for turbulent flow. Next, we discuss differences between turbulent and laminar flow and turn to the Lévêque analogy for laminar flow. This enables heat transfer coefficients (Nusselt numbers) to be derived, based on the flow friction results that include only viscous friction. Some examples of Lévêque analogy applications, such as flow through packed beds, wire gauzes, short-channel structures (short monoliths), and structured catalyst carriers (tube inserts), are given. The Lévêque analogy gave satisfactory accuracy when compared to experiments with flow friction derived on the theoretical basis.
Improved Method for the ASTM Platelet and Leukocyte Assay: Use of Minimal Heparinization in a Screening Test for Hemocompatibility of Blood-Contacting Medical Devices
Authors: Schatz Tim , Howard Sarah , Porter Deanna , Grove Kent , Smith Mark E. , Chen Yan
Published: October 2018

Most blood-contacting medical devices must be assessed for potential thrombogenicity prior to regulatory approval. A common assay for screening and qualifying devices involves monitoring the reduction of platelet and leukocyte (P&L) counts in whole blood exposed to the device. We have validated an improved method for assessing a device's effect on platelet activation and surface adhesion, offering significant improvement over the current ASTM F2888-13 method, which uses blood fully anticoagulated by acidified citrate (known to significantly inhibit platelet responsiveness). Our method uses minimal heparinization (final concentration 1 IU/mL) to optimize the response to commonly used control materials: latex, black rubber, and high-density polyethylene (HDPE). We also have shown the assay's capacity to appropriately assess a legally marketed comparator device (LMCD) with a documented clinical history. The test materials were prepared for incubation and allowed to remain in contact with the citrated or heparinized blood for ∼1 h at 37 °C. A complete blood count was performed prior to exposure, and at the end of the incubation period, reductions in P&L counts were recorded. Results from citrate-anticoagulated assay showed only a marginal response to the positive control, black rubber. Using heparinized blood, the assay generated a robust response to the positive controls, the “intermediate scoring” controls, and also assessed a legally marketed and approved device as clearly nonthrombogenic. This modification adds robustness and sensitivity to this quick and inexpensive thrombogenicity assay and should be incorporated into the next ASTM standards.
Nonlinear Wave Crest Distribution on a Vertical Breakwater
Authors: Laface Valentina , Malara Giovanni , Arena Felice , Kougioumtzoglou Ioannis A. , Romolo Alessandra
Published: October 2018

The paper addresses the problem of deriving the nonlinear, up to the second order, crest wave height probability distribution in front of a vertical wall under the assumption of finite spectral bandwidth, finite water depth and long-crested waves. The distribution is derived by relying on the Quasi-Deterministic representation of the free surface elevation in front of the vertical wall. The theoretical results are compared against experimental data obtained by utilizing a compressive sensing algorithm for reconstructing the free surface elevation in front of the wall. The reconstruction is pursued by starting from recorded wave pressure time histories obtained by utilizing a row of pressure transducers located at various levels. The comparison shows that there is an excellent agreement between the proposed distribution and the experimental data and confirm the deviation of the crest height distribution from the Rayleigh one.
A perceptual dissimilarities based nonlinear sound quality model for range hood noise
Authors: Li Han , Chen Kean , Wang Xue , Gao Yan , Yu Weiwei
Published: October 2018

The application of sound quality in household appliances has gradually increased in recent years. In addition to modeling algorithms, appropriate acoustic metrics that characterize product sounds also play an important role in developing models. In this study, an artificial neural network based sound quality model for range hood noise was established with the combination of prior metric selection by multidimensional scaling (MDS) analysis of perceptual dissimilarities. First, sounds in different environments, speeds, and positions were recorded, and their annoyance was evaluated by grouped anchor semantic differential subjective jury testing. Then, the timbre space underlying dissimilarity judgments were analyzed by CLASCAL, an accurate MDS algorithm. Each dimension of the space was well explained by some metrics through stepwise regression. Finally, a sound quality model was established based on a back propagation neural network (BPNN). Results show that the combination of BPNN and CLASCAL can address the interpretation of the sound quality model and the ability to model nonlinearity for high accuracy. In addition, the application of noise control on range hoods showed that passive and active noise control (ANC) measures improve sound quality, especially ANC systems.
FK506 Resistance of
Saccharomyces cerevisiae
Pdr5 and
Candida albicans
Cdr1 Involves Mutations in the Transmembrane Domains and Extracellular Loops
Authors: Tanabe Koichi , Bonus Michele , Tomiyama Susumu , Miyoshi Kunji , Nagi Minoru , Niimi Kyoko , Chindamporn Ariya , Gohlke Holger , Schmitt Lutz , Cannon Richard D. , Niimi Masakazu , Lamping Erwin
Published: October 2018

The 23-membered-ring macrolide tacrolimus, a commonly used immunosuppressant, also known as FK506, is a broad-spectrum inhibitor and an efflux pump substrate of pleiotropic drug resistance (PDR) ATP-binding cassette (ABC) transporters. Little, however, is known about the molecular mechanism by which FK506 inhibits PDR transporter drug efflux.
Impact of Replication Stress in Human Papillomavirus Pathogenesis
Authors: Moody Cary A.
Published: October 2018

The inactivation of critical cell cycle checkpoints by the human papillomavirus (HPV) oncoprotein E7 results in replication stress (RS) that leads to genomic instability in premalignant lesions. Intriguingly, RS tolerance is achieved through several mechanisms, enabling HPV to exploit the cellular RS response for viral replication and to facilitate viral persistence in the presence of DNA damage.
Segregation but Not Replication of the
Pseudomonas aeruginosa
Chromosome Terminates at
Dif
Authors: Bhowmik Bijit K. , Clevenger April L. , Zhao Hang , Rybenkov Valentin V.
Published: October 2018

Segregation of genetic information is a central event in cellular life. In bacteria, chromosome segregation occurs concurrently with replication, sequentially along the two arms from
oriC
to
dif
. How the two processes are coordinated is unknown. We explored here chromosome segregation in an opportunistic human pathogen,
Pseudomonas aeruginosa
, using its strain with markedly unequal chromosomal arms. We found that replication and segregation diverge in this strain and terminate at very different locations, whereas the longer chromosomal arm folds into large domains to align itself with the shorter arm. The significance of this research is in establishing that segregation and replication of bacterial chromosomes are largely uncoupled from each other and that the large-scale structure of the chromosome adapts to its subcellular layout.
Lymphatic vessels identified in failed corneal transplants with neovascularisation
Authors: Diamond Michael Adam , Chan Sze Wah Samuel , Zhou Xun , Glinka Yelena , Girard Eileen , Yucel Yeni , Gupta Neeru
Published: October 2018

Background

Corneal transplant failure with neovascularisation is a leading indication for full-thickness grafts in patients. Lymphangiogenesis is implicated in the pathology of graft failure, and here we systematically evaluate failed human corneal transplants with neovascularisation for the presence of lymphatic vessels.

Methods

Nine failed grafts with neovascularisation, based on H<E staining with subsequent immunoperoxidase staining for CD31, a blood vessel marker, were selected. Lymphatics were investigated by immunohistochemical and immunofluorescence approaches using podoplanin as a lymphatic marker. In two of nine cases, fluorescence in situ hybridisation (FISH) was used for detection of lymphatic mRNAs including podoplanin,
VEGFR-3
and
LYVE-1
. All immunofluorescence and FISH samples were compared with positive and negative controls and visualised by confocal microscopy.

Results

Corneal neovascularisation was established in all cases by H<E and further confirmed by CD31 immunoreactive profiles. Immunohistochemistry for the podoplanin antibody was positive in all cases and showed morphologies ranging from distinct luminal structures to elongated profiles. Simultaneous immunofluorescence using CD31 and podoplanin showed lymphatic vessels distinct from blood vessels. Podoplanin immunofluorescence was noted in seven of nine cases and revealed clear lumina of varying sizes, in addition to lumen-like and elongated profiles. The presence of lymphatic mRNA was confirmed by FISH studies using a combination of at least two of podoplanin,
VEGFR-3
and
LYVE-1
mRNAs.

Conclusions

The consistent finding of lymphatic vessels in failed grafts with neovascularisation implicates them in the pathogenesis of corneal transplant failure, and points to the lymphatics as a potential new therapeutic target.
Surgical management of acquired implantation iris cysts: indications, surgical challenges and outcomes
Authors: Shanbhag Swapna S , Ramappa Muralidhar , Chaurasia Sunita , Murthy Somasheila I
Published: October 2018

Purpose

To describe the clinical spectrum, clinicopathological correlation and outcomes of different surgical strategies in the management of acquired implantation iris cysts.

Methods

From 1 January 1989 to 31 December 2015, 27 patients (27 eyes) with acquired implantation iris cysts underwent surgery. The charts were reviewed for demographics, preoperative characteristics, surgical approach, histopathological records of excised cyst and postoperative outcomes.

Results

The median age at presentation was 5 years (IQR: 1.3–14 years). Out of 27 patients, 21 (78%) were aged≤18 years. Almost two-third (17/27, 63%) patients had history of penetrating ocular trauma prior to surgery. All patients underwent cyst aspiration combined with complete cyst excision with additional surgical procedures when necessary. Along with complete cyst excision, sector iridectomy was performed in 20/27 (74%) eyes. At a median postoperative follow-up period of 8 months (range: 1–72 months), recurrence was noted in 3/27 (11%) cases at a mean follow-up period of 2.3±1.5 months postsurgery. Eyes in which sector iridectomy was performed had lower incidence of recurrence, and this was statistically significant (p=0.03). However, the improvement in best-corrected visual acuity postoperatively was not statistically significant (p=0.15).

Conclusion

Acquired implantation iris cysts are associated with significant ocular morbidity. Complete excision of the cyst with sector iridectomy is an effective treatment option if other less invasive surgical approaches fail. Visual acuity can be significantly improved but is typically limited due to associated comorbidities.
Another possible planar tetracoordinate carbon saturated hydrocarbon, a computational study
Authors: Lewars Errol
Published: October 2018

Building on earlier computational work by Radom and Rasmussen, the author found a smaller candidate (C17H16) for a hydrocarbon with a planar tetracoordinate carbon atom than the candidate (C23H24) that had been reported by those workers. This molecule is apparently very unstable but nevertheless significant because it may be the smallest neutral hydrocarbon with such a carbon atom and its smaller size makes it easier to study at high computational levels.
New Higher-Order Models for Sandwich Plates with a Flexible Core and their Accuracy Assessment
Authors: Tian Ali , Ye Renchuan , Ren Peng , Jiang Pengming , Chen Zengtao , Yin Xiaochun , Zhao Yuanshuai
Published: October 2018

Two higher-order analytical models based on a new higher-order theory for sandwich plates with flexible cores are developed considering the effect of the core material density and skin-to-core-stiffness-ratio (SCSR). The main difference between the two models is the role of the flexible core in the dynamic response of sandwich plates with cores of different stiffnesses. Firstly, the governing equations of a simply supported sandwich plate with a flexible core are derived based on the two models, and the analytical solutions are determined by using Navier’s approach. Then, the free vibration, static, dynamic bending and stress field characteristics of the sandwich plates with different SCSRs are investigated. The results obtained by the proposed method are compared with other published results. In particular, an accuracy assessment of the present dynamic models is conducted for different SCSRs. Finally, conclusions on the applicability of the proposed method and other theories on sandwich plates with different SCSRs are drawn.
Test-Equivalence Analysis for Automatic Patch Generation
Authors: Mechtaev Sergey , Gao Xiang , Tan Shin Hwei , Roychoudhury Abhik
Published: October 2018

Automated program repair is a problem of finding a transformation (called a patch) of a given incorrect program that eliminates the observable failures. It has important applications such as providing debugging aids, automatically grading student assignments, and patching security vulnerabilities. A common challenge faced by existing repair techniques is scalability to large patch spaces, since there are many candidate patches that these techniques explicitly or implicitly consider.

The correctness criteria for program repair is often given as a suite of tests. Current repair techniques do not scale due to the large number of test executions performed by the underlying search algorithms. In this work, we address this problem by introducing a methodology of patch generation based on a test-equivalence relation (if two programs are “test-equivalent” for a given test, they produce indistinguishable results on this test). We propose two test-equivalence relations based on runtime values and dependencies, respectively, and present an algorithm that performs on-the-fly partitioning of patches into test-equivalence classes.

Our experiments on real-world programs reveal that the proposed methodology drastically reduces the number of test executions and therefore provides an order of magnitude efficiency improvement over existing repair techniques, without sacrificing patch quality.
The partnership on AI
Authors: Heer Jeffrey
Published: October 2018

The Partnership on AI to Benefit People and Society (or PAI) is a consortium of industrial, non-profit, and academic partners for promoting public understanding and beneficial use of Artificial Intelligence (AI) technologies. Primary goals of the PAI are "to study and formulate best practices on AI technologies, to advance the public's understanding of AI, and to serve as an open platform for discussion and engagement about AI and its influences on people and society."
Development and Disciplinary Complicity: Contract Archaeology in South America Under the Critical Gaze
Authors: Gnecco Cristóbal
Published: October 2018

In South America, as elsewhere, development projects have to go through environmental permitting, a component of which is the archaeological assessment of the areas to be impacted. Because such an assessment is paid for by the development companies seeking such a permit, it has come to be known as contract archaeology. Given the accelerated pace of development projects in the region, it is not surprising that contract archaeology has grown exponentially. The academic literature dealing with it and related fields has also witnessed a rapid growth, which this article seeks to review. In doing so, it discusses the literature that accepts and promotes contract archaeology ( a) as a part of environmental permitting; ( b) as the primary stimulus responsible for widening the job market, whose structure has transformed disciplinary practice to a large extent; and ( c) in terms of its relationship with the archaeological record and with heritage education. This article also reviews a growing literature, both supportive and critical, that assesses contract archaeology.
Industrial Meat Production
Authors: Blanchette Alex
Published: October 2018

This review surveys the past 30 years of the anthropology of corporate animal agribusiness, analyzing how various themes embedded in the words of the article's title—industrial, meat, and production—have been taken up by ethnographers of confinement farms and mechanized slaughterhouses. In so doing, it describes how the literature finds the animal life-and-death cycle underlying modern meat to be a hybrid and uneven mixture of industrialisms both old and emerging, at once violent and caring, far-reaching yet incomplete. The review further examines the numerous and distinct ways that scholars have suggested that industrial meat production is an exceptional kind of industrialism: one that requires analytics, ethics, forms of critique, and modes of attention that differ from those developed by studies of other sites of manufacturing.
Fog Computing-Based IoT for Health Monitoring System
Authors: Paul Anand , Pinjari Hameed , Hong Won-Hwa , Seo Hyun Cheol , Rho Seungmin
Published: October 2018

Wireless sensor networks (WSNs) are widely used in the area of health informatics. Wireless and wearable sensors have become prevalent devices to monitor patients at risk for chronic diseases. This helps ascertain that patients comply by the treatment plans and also safeguard them during sudden attacks. The amount of data that are gathered from various sensors is numerous. In this paper, we propose to use fog computing to help monitor patients suffering from chronic diseases such that the data are collected and processed in an efficient manner. The main challenge would be to only sort out context-sensitive data that are relevant to the health of the patient. Just having a simple sensor-to-cloud architecture is not viable, and this is where having a fog computing layer makes a difference. This increases the efficiency of the entire system, as it not only reduces the amount of data that is transported back and forth between the cloud and the sensors but also eliminates the risk that a data center failure bears with it. We also analyze the security and deployment issues of this fog computing layer.
Associations between Sleep-Disordered Breathing and Metabolic Risk Factors beyond Obesity
Authors: Wakabayashi Yusuke , Oka Rie , Nakaya Masako , Karashima Shigehiro , Kometani Mitsuhiro , Sakurai Masaru , Yoshimura Kenichi , Yoneda Takashi
Published: October 2018

Objective. Individuals with multiple metabolic risk factors often experience concomitant sleep-disordered breathing (SDB). We aimed to determine the associations of SDB with individual components of metabolic syndrome independent of obesity.Methods. A cross-sectional study was conducted in 1137 employees aged 30–64 years. Apnea-hypopnea index (AHI) was assessed using a portable monitor for obstructive sleep apnea by admission. Of these, 451 participants took an oral glucose tolerance test to assess homeostatic model assessment of insulin resistance (HOMA-IR) and Matsuda insulin sensitivity index (ISI).Results. The odds ratio (OR) of the highest category of the AHI (≥15 episodes per hour) compared to the lowest one (<5 episodes per hour) was significantly elevated for hypertension, for hypertriglyceridemia, and for low HDL-cholesterolemia when adjusted for age, sex, and alcohol and smoking status (p<0.05). After further adjustment for body mass index (BMI) or waist circumference, the associations for hypertension still remained statistically significant (p<0.05) while those for hypertriglyceridemia and low HDL-cholesterolemia were no longer significant. The association between higher insulin resistance as assessed by HOMA-IR and Matsuda ISI and higher categories of the AHI was also lost after adjustment for BMI.Conclusion. Obesity was a strong confounding factor in the association between SDB and most metabolic risk factors including insulin resistance, except for hypertension. Further longitudinal study is needed to examine the temporal or causal relationships between SDB and metabolic risk factors. This trial is registered with UMIN-CTRUMIN000028067.
Quorum Sensing and Spoilage Potential of Psychrotrophic Enterobacteriaceae Isolated from Milk
Authors: Martins Maurilio Lopes , Pinto Uelinton Manoel , Riedel Katharina , Vanetti Maria Cristina Dantas
Published: October 2018

The 16S rDNA of six psychrotrophic Enterobacteriaceae isolated from cold raw milk were sequenced and the isolate 039 was identified asPantoeasp., isolates 059, 068, and 071 were identified asHafnia alvei, 067 was identified asEnterobactersp., and 099 was identified asAeromonas hydrophila. They presented different spoilage potentials in milk withA. hydrophila099 being the most deteriorative. OnlyPantoeasp. 039 was not able to induce the quorum sensing monitor strains of acyl homoserine lactones (AHLs). ThehalIgene, which encodes the AHL synthase inH. alvei, was identified in the isolates 059, 067, 068, and 071. After initial sequencing characterization and cloning, this gene showed its function by the heterologous synthesis of N-hexanoyl-DL-homoserine lactone and N-3-oxohexanoyl-L-homoserine lactone inEscherichia coli. In addition to producing AHLs,A. hydrophila099 produced AI-2 in higher level than the assay’s positive controlVibrio harveyiBB120. Therefore, Enterobacteriaceae strains isolated from cooled raw milk produce a rich array of signaling molecules that may influence bacterial traits in the milk environment.
Preparation and Properties of a Flexible Al2O3/Al/Al2O3 Composite
Authors: Tong Yigang , Zhou Zhibin , Cai Hui , Wang Xueliang , Wang Yaping
Published: October 2018

A flexible Al2O3/Al/Al2O3 sandwich composite was prepared by microarc oxidation (MAO) on an aluminum foil with 50 μm thickness. The obtained ceramic layers with a thickness of 20–22 μm on the surface of the aluminum foil are mainly Al2O3. The composite, with exterior layers of Al2O3, can be bent more than 90° without observable fracture or delamination. The morphology of the MAO coatings, which has been characterized by scanning electronic microscopy (SEM), is porous and contains microcracks. The energy‐dispersive spectrum (EDS) and the X‐ray diffraction (XRD) results indicate that the MAO coatings mainly contain γ‐Al2O3. Based on experimental observations, the flexibility mechanism was explained by the presence of the microcracks which improve the toughness and decrease the stiffness of the MAO coatings. The well‐adhered layers of the sandwich structure can also prevent the fracture of the MAO coating. The thermal diffusivity of the composite is between that of aluminum and Al2O3 and the specific electrical resistance is 45.4% of that of Al2O3 under 50 V. This composite has the potential to be applied as tailorable low‐voltage insulation material.