bluuebunny/crossref_metadata_2025 huggingface dataset:
THE EFFECTS OF DIFFERENT SONICATION TIMES OF NICKEL OXIDE AND ZIRCONIUM OXIDE CATALYSTS IN SYNGAS PRODUCTION
Authors: Wong Y. C. , Wan Nurdiyana W. A. , Taufiq Yap Y. H.
Published: October 2018

Heterogeneous catalytic cracking is currently one of the most effective ways for both reducing tar content and enhancing hydrogen (H2) content in syngas at relatively low temperature, besides being environmental friendly. Sonochemical treatment has also been shown to lower reaction times with enhanced reaction rate and enables production of particles with high surface area. In this study, two different types of metal oxides, which are Nickel oxide (NiO) and Zirconium oxide (ZrO2) at a combination of 1:1 ratio with Zeolite as the supporter are synthesized via sonochemical treatment in durations of 30, 60 and 90 minutes. The catalysts are then characterized using X-Ray Diffraction (XRD), Temperature Programmed Reduction (TPR-H2), Brunauer-Emmett-Teller surface measurement (BET), Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). From SEM and TEM analysis, Nickel tends to agglomerate and form sizable globular shapes, Zirconium forms coral-like branching structure and Zeolite forms stacks of cubic clumps. The most promising sonication treatment duration for the catalysts is 30 minutes because it removes decent amount of reactive oxygen at a rate of 0.83 x 1021 atoms/g during hydrogen reduction, possesses the highest surface area of 506.52 m2/g as well as smallest average crystallite size of 56.9 nm compared to other durations. Generally sonochemical treatment also increases the catalysts surface area and oxygen removal as well as lowers the reduction temperature which is favourable in term of production cost. Catalysts with sonochemical treatment duration of 30 and 60 minutes generally show higher reactive oxygen removal and surface area compared to catalysts with 90 minute treatments.
THE EFFECT OF ETHANOL ON FUEL TANK CORROSION RATE
Authors: Setiyo Muji , Saifudin Saifudin , Jamin Abdul Wahid , Nugroho Rifqi , Karmiadji Djoko Wahyu
Published: October 2018

In recent decades, the use of ethanol as an alternative fuel for S.I. engines has become a popular issue. This is not only due to availability and oil prices, but also to address concerns about the increase in greenhouse gas effects. However, ethanol is corrosive in a fuel tank made of metal, because it contains soluble chloride ions. Therefore, this paper presents the results of an investigation of the fuel tank corrosion rate made of metal Fe_U_100 due to the use of pure ethanol. The test was performed by PGS-120T potentiostat with the addition of NaCl in ethanol in concentrations of 5, 10, 15, 20, and 25% while the estimated corrosion rate on pure ethanol was done by regression. The estimation of the fuel tank corrosion rate through the exponential regression for the use of pure ethanol is 4,116 mpy. Then, from the assessment metrics, the fuel tank made of Fe_U_100 has corrosion resistance in the excellent category. This means no fuel tank modification or replacement is required for pure ethanol applications in S.I. engine.
Degradation Modeling and Remaining Useful Life Prediction of Aircraft Engines Using Ensemble Learning
Authors: Li Zhixiong , Goebel Kai , Wu Dazhong
Published: October 2018

Degradation modeling and prediction of remaining useful life (RUL) are crucial to prognostics and health management of aircraft engines. While model-based methods have been introduced to predict the RUL of aircraft engines, little research has been reported on estimating the RUL of aircraft engines using novel data-driven predictive modeling methods. The objective of this study is to introduce an ensemble learning-based prognostic approach to modeling an exponential degradation process due to wear as well as predicting the RUL of aircraft engines. The ensemble learning algorithm combines multiple base learners, including random forests (RFs), classification and regression tree (CART), recurrent neural networks (RNN), autoregressive (AR) model, adaptive network-based fuzzy inference system (ANFIS), relevance vector machine (RVM), and elastic net (EN), to achieve better predictive performance. The particle swarm optimization (PSO) and sequential quadratic optimization (SQP) methods are used to determine optimum weights that are assigned to the base learners. The predictive model trained by the ensemble learning algorithm is demonstrated on the data generated by the commercial modular aero-propulsion system simulation (C-MAPSS) tool. Experimental results have shown that the ensemble learning algorithm predicts the RUL of the aircraft engines with considerable robustness as well as outperforms other prognostic methods reported in the literature.
Experimental and Numerical Analysis of Mixing Process of Two Component Gases in a Vertical Fluid Layer in a VHTR
Authors: Takeda Tetsuaki
Published: October 2018

When a depressurization accident of a very-high-temperature reactor (VHTR) occurs, air is expected to enter into the reactor pressure vessel from the breach and oxidize in-core graphite structures. Therefore, in order to predict or analyze the air ingress phenomena during a depressurization accident, it is important to develop a method for the prevention of air ingress during an accident. In particular, it is also important to examine the influence of localized natural convection and molecular diffusion on the mixing process from a safety viewpoint. Experiment and numerical analysis using a three-dimensional (3D) computational fluid dynamics code have been carried out to obtain the mixing process of two-component gases and the flow characteristics of localized natural convection. The numerical model consists of a storage tank and a reverse U-shaped vertical rectangular passage. One sidewall of the high-temperature side vertical passage is heated, and the other sidewall is cooled. The low-temperature vertical passage is cooled by ambient air. The storage tank is filled with heavy gas and the reverse U-shaped vertical passage is filled with a light gas. The result obtained from the 3D numerical analysis was in agreement with the experimental result quantitatively. The two component gases were mixed via molecular diffusion and natural convection. After some time elapsed, natural circulation occurred through the reverse U-shaped vertical passage. These flow characteristics are the same as those of phenomena generated in the passage between a permanent reflector and a pressure vessel wall of the VHTR.
Review of Causes and Mitigation of Cavity Noise in Machinery and Other Mechanisms
Authors: Kushner Frank
Published: October 2018

Two significant causes of noise related to cavities are direct and indirect flow induced turbulence/vortex shedding mechanisms. Examples of induced noise can be found in many applications of both closed-flow and open-flow cavities — some with resonance of acoustic modes. An example is a flow valve with a cavity where flow along the cavity gives pulsations either trapped within the valve or exciting downstream piping acoustic modes. There are passive methods of mitigation besides detuning such as modification of the entrance to the cavity, blockage, and use of Helmholtz resonators. Natural frequencies of cavity acoustic modes can be irregular, but for many such as with circular, square, rectangular or axisymmetric shapes can give symmetry of modes. An example is a cavity at the sides of rotating disks, where transverse symmetrical modes having circular and diametric patterns are similar to structural vibratory modes for bladed disks. In the last decade it has been documented that for centrifugal compressors blade passing acoustic pressure pulsation due to Tyler-Sofrin spinning modes can add to alternating stress from non-uniform flow excitation, such as from stator wakes. Cavity acoustic mode excitation then has been termed “triple coincidence” or “triple crossing”, explaining rare documented impeller fatigue failures and likely a reason, at least partially, for some unexplained failures. A novel method described herein is to treat these and similar cavities as fluid-filled disks, then utilize or add blade-like elements within the cavities. The method described (patent application, PCT US1820880) to reduce response of these cavities is to intentionally mistune the elements as has been documented for bladed disk modes. Other applications of this method are possible for many other mechanisms. These modification(s) can alleviate concern for any mechanism having structural vibration excitation acoustically and/or for environmental noise issues.
Research on Vibration Control of Thin Plate Based on Pre-Stressing
Authors: Zhang Cheng , Zhang Jian-run , Lu Xi
Published: October 2018

The weak dynamic stiffness of thin plate is one of the important factors that limit the use of thin plate. Improving the dynamic stiffness of thin plate is one of the effective methods for the vibration control of thin plate. In this paper, the influence of pre-stress on the vibration characteristics of thin plate is studied. A vibration control method of thin plate based on pre-stress is proposed. The vibration differential equation of quadrate thin plate under pre-stressing is established. Using the Galerkin principle, the natural frequencies corresponding to the shape functions of the quadrate thin plates under pre-stressing in different distribution forms are obtained. By comparison, it is found that pre-stressing on the thin plate can change the dynamic stiffness of thin plate. In particular, tensile stress can increase the dynamic stiffness of thin plate while compressive stress can reduce the dynamic stiffness of the thin plate. The greater the pre-stress, the more obvious the effect. In the end, the requirements of the pre-stress distribution which can improve the dynamic stiffness of thin plate effectively are derived.
Free Vibration Analysis of Rectangular Thin Plate With Multiple Openings Under General Boundary Conditions
Authors: Nie Rui , Li Tianyun , Zhu Xiang , Guo Wenjie
Published: October 2018

The free vibration characteristics of a rectangular thin plate with series of openings are studied based on the Rayleigh-Ritz method in this paper. Firstly, the strain energy and kinetic energy of the plate are calculated utilizing the modified Fourier series. Then, uniformly distributed transitional and rotational springs are applied to deal with general boundary supports, and the elastic potential energy of the springs can be obtained. Furthermore, the plate is divided into several parts according to its amounts of openings and the energy of each parts are calculated separately and the spring stiffness of cut line between two separated parts are the same. Finally, the governing equation of the plate is obtained with the energy functional variation method. The present method is proved to be accurate by comparing the natural frequencies with those calculated by the finite element method. Besides, the influence of the amounts of openings and the area of total openings are discussed.
Acoustical Comfort in Classrooms: Case Study at the University of Brasília
Authors: Daga Clarice C. , Lobo Hetty N. C. C. , Lobo José A. P. C. , Melo Carlos E. L.
Published: October 2018

The acoustic conditions in school spaces are fundamental for the success of the learning process. This article aims to present the results of acoustic comfort by the analytical method of 9 classrooms with different geometric characteristics of the University of Brasília. In classrooms the background noise limits are 40 to 50dBA and considering that the teacher’s voice reaches a certain 65 decibels we can highlight that it can be heard clearly by the students. However in an environment with a lot of reverberation of sounds the teacher will have to exert more effort to be understood. The sound perception in a room depends on the intensity and temporal relationship between the direct sound and the indirect sound reflected by the walls of the room, therefore, in the present study were verified two parameters namely the reverberation time and speech intelligibility. The results obtained were compared with the normative parameters of ANSI S12.60: 2010 and it was verified that all rooms are not suitable for teaching-learning activity. To guarantee an environment with better conditions of concentration and learning for the students, acoustic coverings were suggested in order to fit the normative limits.
Sound Quality of Aircraft Cabin for VIP and Business Jets
Authors: Gurun Nurkan Turkdogru , Sheth Hemang N.
Published: October 2018

This paper aims to identify the attributes that describe aircraft interior noise, determine most important psychoacoustic models that characterize cabin sounds, and construct a prediction model that can be utilized for VIP and business jets to evaluate subjective perception. In the first part, paired comparison listening tests and free verbalization are conducted with expert subjects who experienced VIP and business aircraft flight. The study generated a list of adjective pairs that describe perception of cabin sounds to be used for semantic differential listening tests. Multi-dimensional scaling is performed on paired comparison data. Results showed that subjects’ decisions can be categorized in loudness and annoyance dimensions which are not necessarily linearly associated. The second part of the study is the development of a sound quality prediction model for aircraft cabin. Semantic differential tests are conducted with potential customers. Objective sound quality metrics are correlated to subjective test responses using principal components regression. This model is found to be most effective explaining pleasantness, comfort, and loudness perception. It is intended to be utilized to modify/redesign noise control treatments and sound signature of an aircraft. All listening tests were conducted inside an aircraft cabin simulator considering the influence of visual content.
An Analytical and Numerical Investigation of Modulation Sidebands of a Planetary Gear Under Fluctuated External Torque
Authors: Yuan Yunbo , Liu Wei , Chen Yahui , Wang Donghua
Published: October 2018

Certain operating conditions such as fluctuation of the external torque to planetary gear sets can cause additional sidebands. In this paper, a mathematical model is proposed to investigate the modulation mechanisms due to a fluctuated external torque (FET), and the combined influence of such an external torque and manufacturing errors (ME) on modulation sidebands. Gear mesh interface excitations, namely gear static transmission error excitations and time-varying gear mesh stiffness, are defined in Fourier series forms. Amplitude and frequency modulations are demonstrated separately. The predicted dynamic gear mesh force spectra and radial acceleration spectra at a fixed position on ring gear are both shown to exhibit well-defined modulation sidebands. Comparing with sidebands caused by ME, more complex sidebands appear when taking both FET and ME into account. An obvious intermodulation is found around the fundamental gear mesh frequency between the FET and ME in the form of frequency modulations, however, no intermodulation in the form of amplitude modulations. Additionally, the results indicate that some of the sidebands are cancelled out in radial acceleration spectra mainly due to the effect of planet mesh phasing, especially when only amplitude modulations are present.
Associations of Sedentary Behavior and Abdominal Muscle Density: The Multi-Ethnic Study of Atherosclerosis
Authors: Vella Chantal A. , Michos Erin D. , Sears Dorothy D. , Cushman Mary , Van Hollebeke Rachel B. , Wiest Michelle M. , Allison Matthew A.
Published: October 2018

Background: Sedentary behaviors (SB) may exacerbate loss of muscle mass and function, independent of physical activity levels. This study examined the associations of SB with abdominal muscle area and density, a marker of muscle quality, in adults. Methods: A total of 1895 participants from the Multi-Ethnic Study of Atherosclerosis completed detailed health history, physical activity and SB questionnaires, computed tomography to quantify body composition, and measurements of inflammatory markers. Analyses included linear and nonlinear regression. Results: The mean age and body mass index were 64.6 years and 28 kg·m−2, respectively, and 50% were women. On average, participants engaged in 28 metabolic equivalent hours·week−1 of SB. With adjustment for age, sex, race/ethnicity, physical activity, cardiovascular disease risk factors, and inflammation, multivariable regression modeling revealed a nonlinear (quadratic) relationship between SB and locomotor, stability, and total abdominal muscle density (P < .01) but not muscle area. The SB inflection point at which locomotor, stability, and total abdominal muscle density began to decrease was 38.2, 39.6, and 39.2 metabolic equivalent hours·week−1 of SB, respectively. Conclusions: SB is associated with reduced muscle density when practiced as little as 5.5 metabolic equivalent hours·day−1. These findings may have important implications for SB guidelines for targeting skeletal muscle health in older adults.
Ironing out the mechanisms of chronic bacterial infection
Authors: Langelier Chaz
Published: October 2018

Molecular evaluation reveals an important role for nutrient-dependent intracellular trafficking in chronic bacterial otitis media.
Draft Genome Sequences of 10 Clinical K2-Type Klebsiella pneumoniae Strains Isolated in Russia
Authors: Volozhantsev Nikolay V. , Kislichkina Angelina A. , Lev Anastasia I. , Solovieva Ekaterina V. , Myakinina Vera P. , Mukhina Tatiana N. , Bogun Alexandr G. , Fursova Nadezhda K.
Published: October 2018

We report here the genome sequences of 10
Klebsiella pneumoniae
strains of capsular type K2 isolated in Russia from patients in an infectious clinical hospital and neurosurgical intensive care unit. The draft genome sizes range from 5.34 to 5.87 Mb and include 5,448 to 6,137 protein-coding sequences.
Draft Genome Sequence of Escherichia coli Phage CMSTMSU, Isolated from Shrimp Farm Effluent Water
Authors: Chinnadurai Lelin , Eswaramoorthy Thirumalaikumar , Paramachandran Abinaya , Paul Sayan , Rathy Rashmi , Arumugaperumal Arun , Sivasubramaniam Sudhakar , Thavasimuthu Citarasu
Published: October 2018

The
Escherichia coli
phage CMSTMSU was isolated from shrimp farm effluent water in Ramanathapuram, India. The phage exhibited lytic activity against both
E.
coli
and the fish pathogen
Pseudomonas aeruginosa
.
Draft Genome Sequence of Rhodopirellula baltica Strain BR-MGV, a Planctomycete Isolated from Brazilian Mangrove Soil
Authors: Araújo Juliana Eschholz de , Taketani Rodrigo Gouvêa , Pereira e Silva Michele de Cássia , Lourenço Marcus Venicius de Mello , Andreote Fernando Dini
Published: October 2018

Members of the phylum
Planctomycetes
, which are capable of surviving in a wide range of environments, are some of the least-explored bacteria. Here, we report the near-complete draft genome sequence and annotation of the planctomycete
Rhodopirellula baltica
BR-MGV, which was isolated from the soil of a contaminated Brazilian mangrove.
Complete Sequence and Annotation of the Mycoplasma phocidae Strain 105
T
Genome
Authors: Frasca Salvatore , Kutish Gerald F. , Michaels Dina L. , Brown Daniel R.
Published: October 2018

The genome of
Mycoplasma phocidae
strain 105
T
was analyzed in order to improve our understanding of its role in epidemic marine mammal mortalities. It was found to encode a suite of immunosuppressors that may enable evasion of host defenses and modulate susceptibility to viral coinfections or their severity in seals.
Twenty years of research on attention-deficit/hyperactivity disorder (ADHD): looking back, looking forward
Authors: Cortese Samuele , Coghill David
Published: October 2018

In this clinical review we summarise what in our view have been some the most important advances in the past two decades, in terms of diagnostic definition, epidemiology, genetics and environmental causes, neuroimaging/cognition and treatment of attention-deficit/hyperactivity disorder (ADHD), including: (1) the most recent changes to the diagnostic criteria in the Diagnostic and Statistical Manual of Mental Disorders and International Classification of Diseases; (2) meta-analytic evidence showing that, after accounting for diagnostic methods, the rates of ADHD are fairly consistent across Western countries; (3) the recent finding of the first genome-wide significant risk loci for ADHD; (4) the paradigm shift in the pathophysiological conceptualisation of ADHD from alterations in individual brain regions to a complex dysfunction in brain networks; (5) evidence supporting the short-term efficacy of ADHD pharmacological treatments, with a different profile of efficacy and tolerability in children/adolescents versus adults; (6) a series of meta-analyses showing that, while non-pharmacological treatment may not be effective to target ADHD core symptoms, some of them effectively address ADHD-related impairments (such as oppositional behaviours for parent training and working memory deficits for cognitive training). We also discuss key priorities for future research in each of these areas of investigation. Overall, while many research questions have been answered, many others need to be addressed. Strengthening multidisciplinary collaborations, relying on large data sets in the spirit of Open Science and supporting research in less advantaged countries will be key to face the challenges ahead.
Improving survival after an emergency resuscitative thoracotomy: a 5-year review of the Trauma Quality Improvement Program
Authors: Joseph Bellal , Khan Muhammad , Jehan Faisal , Latifi Rifat , Rhee Peter
Published: October 2018

Background

Advancement in trauma care has led to the evolution of emergency resuscitative thoracotomy (ERT) for the revival of trauma patients. We now have more precise understanding of selecting suitable patients for achieving optimal outcomes. The aim of our study was to analyze the utilization and survival trends during the past 5 years, as well as factors that influence survival after ERT.

Methods

A 5-year (2010-2014) analysis of all trauma patients ≥18 years who underwent ERT in the American College of Surgeons Trauma Quality Improvement Program. Outcome measures were utilization rates and survival trends after ERT during the 5-year period. Regression analysis was performed.

Results

2229 patients underwent ERT, mean age was 37±17 years, 81% were male. Overall 56% patients had penetrating mechanism, location of major injury was thorax in 48, and 71% had signs of life (SOL) on arrival. The overall survival rate was 9.6%. From 2010–2014 ERT utilization has decreased from 331/100 000 to 243/100 000 trauma admissions (p=0.002) and the survival rate has improved from 7.9% to 11.3% (p<0.001). On regression, the independent predictors of survival were penetrating mechanism, age<60 years, SOL on arrival, no prehospital CPR and ISS. No patient aged >60 years with a blunt mechanism of injury (MOI) survived, and there were no survivors above the age of 70 years, regardless of injury mechanism.

Discussion

Utilization of ERT has been decreased during the study period along with improved survival rates. The results of our study demonstrate that performing ERT on patients aged >60 years with a blunt MOI or on any patient aged ≥70 years, regardless of MOI, is futile and should be avoided.

Level of evidence

Level III, prognostic studies.
Suitability maps for managed aquifer recharge: a review of multi-criteria decision analysis studies
Authors: Sallwey Jana , Bonilla Valverde José Pablo , Vásquez López Felipe , Junghanns Ralf , Stefan Catalin
Published: October 2018

Suitability maps for managed aquifer recharge (MAR) sites hold a strong potential for integration into sustainable groundwater management plans. An uprising method to identify sites suitable for MAR implementation is geographic information system (GIS)-based multi-criteria decision analysis (MCDA). There are no guidelines or a common understanding on how suitability mapping should be conducted, and there is considerable variability as to what factors are assessed and how they are weighted. To increase knowledge on GIS-MCDA, a database has been built based on 63 studies applying GIS-MCDA in the context of MAR site selection. Information on the criteria, assigned weights, and methodologies has been retrieved from the documents. Statistical analysis of the database depicts the current state of art for suitability mapping methodologies as well as specific information for the different recharge methods. We further incorporated the compiled information into a web-based query tool that makes the information easily accessible and the utilization of the database more user friendly. This review as well as the created web-tool will help planners of MAR sites to engage in the MCDA in a more structured way by referring to previously conducted studies and by finding information suitable for their specific project. The application potential of suitability maps is discussed along with the shortcomings of this methodology.
Absence of binding in the Nelson and piezoelectric polaron models
Authors: Bley Gonzalo A.
Published: October 2018

In the context of the massless Nelson model, we prove that two non-relativistic nucleons interacting with a massless meson field do not bind when a sufficiently strong Coulomb repulsion between the nucleons is added to the Hamiltonian. The result holds for both the renormalized and unrenormalized theories, and can also be applied to the so-called piezoelectric polaron model, which describes an electron interacting with the acoustical vibrational modes of a crystal through the piezoelectric interaction. The result can then be interpreted as well as a no-binding statement about piezoelectric bipolarons. The methods used allow also for a significant reduction of about 30% over previously known no-binding conditions for the optical bipolaron model of H. Fröhlich.
Automatic Data Layout Transformations in the ExaStencils Code Generator
Authors: Kronawitter Stefan , Kuckuk Sebastian , Köstler Harald , Lengauer Christian
Published: October 2018

Performance optimizations should focus not only on the computations of an application, but also on the internal data layout. A well-known problem is whether a struct of arrays or an array of structs results in a higher performance for a particular application. Even though the switch from the one to the other is fairly simple to implement, testing both transformations can become laborious and error-prone. Additionally, there are more complex data layout transformations, such as a color splitting for multi-color kernels in the domain of stencil codes, that are manually difficult. As a remedy, we propose new flexible layout transformation statements for our domain-specific language ExaSlang that support arbitrary affine transformations. Since our code generator applies them automatically to the generated code, these statements enable the simple adaptation of the data layout without the need for any other modifications of the application code. This constitutes a big advance in the ease of testing and evaluating different memory layout schemes in order to identify the best.
The production of charged-kaon pairs in proton–antiproton collisions: The role of higher-twist mechanism
Authors: Demirci M. , Ahmadov A. I.
Published: October 2018

The higher-twist (HT) contribution to the charged-kaon pair production in the high energy proton–antiproton collisions at large transverse momentum [Formula: see text] is investigated by using the frozen coupling constant approach for various kaon distribution amplitudes (DAs), which are predicted by light-cone formalism, the light-front quark model, the nonlocal chiral quark model and the light-front holographic AdS/CFT approach. In the numerics, the dependencies of the HT contribution on the transverse momentum [Formula: see text], the rapidity [Formula: see text], and the variable [Formula: see text] are discussed with special emphasis put on DAs. The HT contribution is also compared with the leading-twist ones. It is shown that the HT contributions are dependent on the kaon DAs and also some other phenomenological parameters such as momentum cutoff parameter [Formula: see text]. Inclusive kaon pair production presents a remarkable test case in which HT terms dominate those of LT in certain kinematic regions. The HT direct production process via gluon–gluon fusion contributes significantly to the inclusive cross-section at large [Formula: see text].
On the zero–multiplicity of a fifth-order linear recurrence
Authors: Ruiz Carlos Alexis Gómez , Luca Florian
Published: October 2018

We consider a family of linear recurrence sequences [Formula: see text] of order [Formula: see text] whose first [Formula: see text] terms are [Formula: see text] and each term afterwards is the sum of the preceding [Formula: see text] terms. In this paper, we study the zero–multiplicity on [Formula: see text] when the indices are extended to all integers. In particular, we give a upper bound (dependent on [Formula: see text]) for the largest positive integer [Formula: see text] such that [Formula: see text] and show that [Formula: see text] has zero–multiplicity unitary when the indices are extended to all the integers.
Fujii’s development on Chebyshev’s conjecture
Authors: Platt Dave , Trudgian Tim
Published: October 2018

Chebyshev presented a conjecture after observing the apparent bias towards primes congruent to [Formula: see text]. His conjecture is equivalent to a version of the Generalized Riemann Hypothesis. Fujii strengthened this conjecture; we strengthen it still further using detailed computations of zeroes of Dirichlet [Formula: see text]-functions.
Collaborations on YouTube
Authors: Koch Christian , Lode Moritz , Stohr Denny , Rizk Amr , Steinmetz Ralf
Published: October 2018

YouTube is the most popular platform for streaming of user-generated videos. Nowadays, professional YouTubers are organized in so-called multichannel networks (MCNs). These networks offer services such as brand deals, equipment, and strategic advice in exchange for a share of the YouTubers’ revenues. A dominant strategy to gain more subscribers and, hence, revenue is collaborating with other YouTubers. Yet, collaborations on YouTube have not been studied in a detailed quantitative manner. To close this gap, first, we collect a YouTube dataset covering video statistics over 3 months for 7,942 channels. Second, we design a framework for collaboration detection given a previously unknown number of persons featured in YouTube videos. We denote this framework, for the detection and analysis of collaborations in YouTube videos using a Deep Neural Network (DNN)-based approach, as CATANA. Third, we analyze about 2.4 years of video content and use CATANA to answer research questions guiding YouTubers and MCNs for efficient collaboration strategies. Thereby, we focus on (1) collaboration frequency and partner selectivity, (2) the influence of MCNs on channel collaborations, (3) collaborating channel types, and (4) the impact of collaborations on video and channel popularity. Our results show that collaborations are in many cases significantly beneficial regarding viewers and newly attracted subscribers for both collaborating channels, often showing more than 100% popularity growth compared with noncollaboration videos.
Joint Head Attribute Classifier and Domain-Specific Refinement Networks for Face Alignment
Authors: Zhang Junfeng , Hu Haifeng
Published: October 2018

In this article, a two-stage refinement network is proposed for facial landmarks detection on unconstrained conditions. Our model can be divided into two modules, namely the Head Attribude Classifier (HAC) module and the Domain-Specific Refinement (DSR) module. Given an input facial image, HAC adopts multi-task learning mechanism to detect the head pose and obtain an initial shape. Based on the obtained head pose, DSR designs three different CNN-based refinement networks trained by specific domain, respectively, and automatically selects the most approximate network for the landmarks refinement. Different from existing two-stage models, HAC combines head pose prediction with facial landmarks estimation to improve the accuracy of head pose prediction, as well as obtaining a robust initial shape. Moreover, an adaptive sub-network training strategy applied in the DSR module can effectively solve the issue of traditional multi-view methods that an improperly selected sub-network may result in alignment failure. The extensive experimental results on two public datasets, AFLW and 300W, confirm the validity of our model.
Performance Tuning and Analysis for Stencil-Based Applications on POWER8 Processor
Authors: Xu Jingheng , Fu Haohuan , Shi Wen , Gan Lin , Li Yuxuan , Luk Wayne , Yang Guangwen
Published: October 2018

This article demonstrates an approach for combining general tuning techniques with the POWER8 hardware architecture through optimizing three representative stencil benchmarks. Two typical real-world applications, with kernels similar to those of the winning programs of the Gordon Bell Prize 2016 and 2017, are employed to illustrate algorithm modifications and a combination of hardware-oriented tuning strategies with the application algorithms. This work fills the gap between hardware capability and software performance of the POWER8 processor, and provides useful guidance for optimizing stencil-based scientific applications on POWER systems.
Image Captioning via Semantic Guidance Attention and Consensus Selection Strategy
Authors: Wu Jie , Hu Haifeng , Wu Yi
Published: October 2018

Recently, a series of attempts have incorporated spatial attention mechanisms into the task of image captioning, which achieves a remarkable improvement in the quality of generative captions. However, the traditional spatial attention mechanism adopts latent and delayed semantic representations to decide which area should be paid more attention to, resulting in inaccurate semantic guidance and the introduction of redundant information. In order to optimize the spatial attention mechanism, we propose the Semantic Guidance Attention (SGA) mechanism in this article. Specifically, SGA utilizes semantic word representations to provide an intuitive semantic guidance that focuses accurately on semantic-related regions. Moreover, we reduce the difficulty of generating fluent sentences by updating the attention information in time. At the same time, the beam search algorithm is widely used to predict words during sequence generation. This algorithm generates a sentence according to the probabilities of words, so it is easy to push out a generic sentence and discard some distinctive captions. In order to overcome this limitation, we design the Consensus Selection (CS) strategy to choose the most descriptive and informative caption, which is selected by the semantic similarity of captions instead of the probabilities of words. The consensus caption is determined by selecting the one with the highest cumulative semantic similarity with respect to the reference captions. Our proposed model (SGA-CS) is validated on Flickr30k and MSCOCO, which shows that SGA-CS outperforms state-of-the-art approaches. To our best knowledge, SGA-CS is the first attempt to jointly produce semantic attention guidance and select descriptive captions for image captioning tasks, achieving one of the best performance ratings among any cross-entropy training methods.
The serotonin transporter and nonselective transporters are involved in peripheral serotonin uptake in the Gulf toadfish,Opsanus beta
Authors: Amador Molly H. B. , McDonald M. Danielle
Published: October 2018

In mammals, circulating serotonin [5-hydroxytryptamine (5-HT)] is sequestered by platelets via the 5-HT transporter (SERT) to prevent unintended signaling by this potent signaling molecule. Teleost fish appear to lack a similar circulating storage pool, although the diverse effects of 5-HT in teleosts likely necessitate an alternative method of tight regulation, such as uptake by peripheral tissues. Here, a 5-HT radiotracer was used to explore the 5-HT uptake capacity of peripheral tissues in the Gulf toadfish, Opsanus beta, and to elucidate the primary excretion routes of 5-HT and its metabolites. Pharmacological inhibition of SERT and other transporters enabled assessment of the SERT dependence of peripheral 5-HT uptake and excretion. The results indicated a rapid and substantial uptake of 5-HT by the heart atrium, heart ventricle, and gill that was at least partly SERT dependent. The results also supported the presence of a partial blood-brain barrier that prevented rapid changes in brain 5-HT content despite fluctuating plasma 5-HT concentrations. The renal pathway appeared to be the dominant excretory route for 5-HT and its metabolites over shorter time frames (up to ~30 min), but hepatic excretion was substantial over several hours. SERT inhibition ultimately reduced the excretion of 5-HT and its metabolites by urinary, biliary, and/or intestinal pathways. In addition, branchial excretion of 5-HT and its metabolites could not be ruled out. In summary, this study reveals that the toadfish heart and gill play active roles in regulating circulating 5-HT and yields important insights into the control of peripheral 5-HT in this teleost fish.
Serum and urinary SOD3 in patients with type 2 diabetes: comparison with early chronic kidney disease patients and association with development of diabetic nephropathy
Authors: Kuo Chia-Wen , Chen Hsiao-Ling , Tu Min-Yu , Chen Chuan-Mu
Published: October 2018

Extracellular superoxide dismutase 3 (SOD3), one member of the antioxidant defense system and a superoxide scavenger, has been noted to be downregulated in the kidneys of diabetic mice and is characterized by a heparin-binding domain that can anchor the protein to the endothelium and extracellular matrix. The association of the serum and urinary SOD3 levels with diabetic nephropathy in different stages has never been evaluated. It remains unclear how urinary SOD3 changes in different renal diseases. We recruited 98 Taiwanese patients with type 2 diabetes and 10 patients with early chronic kidney disease (CKD) into this study. Biochemical analyses were performed, including evaluation of the serum SOD3, urinary SOD3, urinary albumin, urinary vascular endothelial growth factor (VEGF), and urinary angiotensinogen (ANG). The Kruskal-Wallis rank sum test was used to compare various parameters among the three groups of patients: early CKD, diabetes alone, and diabetes with CKD. Results showed that lower serum and urinary SOD3 levels were observed in the group of patients with diabetes alone. Higher serum and urinary SOD3 levels were observed in the group of patients with diabetes and CKD, which had higher albuminuria and serum creatinine levels. The serum SOD3 levels were significantly positively correlated with renal function, according to the serum creatinine level. The urinary levels of SOD3 were significantly correlated with other urinary biomarkers such as urinary ANG and VEGF. Furthermore, albuminuria can positively predict the serum SOD3 level for the ratio of urinary albumin to urinary creatinine (ACR) >1,190.769 mg/g and the urinary SOD3 level for ACR ≥300 mg/g.
A conditionally immortalized Gli1-positive kidney mesenchymal cell line models myofibroblast transition
Authors: Ó hAinmhire Eoghainín , Wu Haojia , Muto Yoshiharu , Donnelly Erinn L. , Machado Flavia G. , Fan Lucy X. , Chang-Panesso Monica , Humphreys Benjamin D.
Published: October 2018

Glioma-associated oncogene homolog-1 (Gli1)-positive resident mesenchymal stem cell-like cells are the predominant source of kidney myofibroblasts in fibrosis, but investigating Gli1-positive myofibroblast progenitor activation is hampered by the difficulty of isolating and propagating primary cultures of these cells. Using a genetic strategy with positive and negative selection, we isolated Kidney-Gli1 (KGli1) cells that maintain expression of appropriate mesenchymal stem cell-like cell markers, respond to hedgehog pathway activation, and display robust myofibroblast differentiation upon treatment with transforming growth factor-β (TGF-β). Coculture of KGli1 cells with endothelium stabilizes capillary formation. Single-cell RNA sequencing (scRNA-seq) analysis during differentiation identified autocrine ligand-receptor pair upregulation and a strong focal adhesion pathway signal. This led us to test the serum response factor inhibitor CCG-203971 that potently inhibited TGF-β-induced pericyte-to-myofibroblast transition. scRNA-seq also identified the unexpected upregulation of nerve growth factor (NGF), which we confirmed in two mouse kidney fibrosis models. The Ngf receptor Ntrk1 is expressed in tubular epithelium in vivo, suggesting a novel interstitial-to-tubule paracrine signaling axis. Thus, KGli1 cells accurately model myofibroblast activation in vitro, and the development of this cell line provides a new tool to study resident mesenchymal stem cell-like progenitors in health and disease.
Commercial Video Evaluation via Low-Level Feature Extraction and Selection
Authors: Lun Xiangmin , Wang Mingxuan , Yu Zhenglin , Hou Yimin
Published: October 2018

To discover the influence of the commercial videos’ low-level features on the popularity of the videos, the feature selection method should be used to get the video features influencing the videos’ evaluation mostly after analyzing the source data and the audiences’ evaluations of the videos. After extracting the low-level features of the videos, this paper improved the Correlation-Based Feature Selection (CFS) method which is widely used and proposed an algorithm named CFS-Spearmen which combined the Spearmen correlation coefficient and the classical CFS to select features. The 4 datasets in UCI machine learning database were employed as the experiment data. The experiment results were compared with the results using traditional CFS, Minimum Redundancy and Maximum Relevance (mRMR). The SVM was used to test the method in this paper. Finally, the proposed method was used in commercial videos’ feature selection and the most influential feature set was obtained.
Microstructural Analysis and Magnetic Characterization of Native and Magnetically Modified Montmorillonite and Vermiculite
Authors: Jiraskova Yvonna , Bursik Jiri , Seidlerova Jana , Kutlakova Katerina Mamulova , Safarik Ivo , Safarikova Mirka , Pospiskova Kristyna , Zivotsky Ondrej
Published: October 2018

Two clay minerals of the similar 2 : 1 layer structure and chemical composition, vermiculite and montmorillonite, were studied using a wide spectrum of experimental methods in their original states and the magnetically modified states after mixing with microwave-synthesized iron oxide particles. This magnetic modification led to different microstructural morphology influencing magnetic behaviour at room and more pronounced at low temperatures.
Annual Optical Performance of a Solar CPC Photoreactor with Multiple Catalyst Support Configurations by a Multiscale Model
Authors: Peña-Cruz Manuel I. , Valades-Pelayo Patricio J. , Arancibia-Bulnes Camilo A. , Pineda-Arellano Carlos A. , Salgado-Tránsito Iván , Martell-Chavez Fernando
Published: October 2018

In this work, the seasonal and yearly optical performance of supported catalyst CPC solar photocatalytic reactors has been theoretically analyzed. A detailed model for the optical response of the anatase catalyst films is utilized, based on the characteristic matrix method, together with Monte Carlo ray tracing simulations. The catalyst is supported over glass tubes contained inside a larger glass tube that functions as receiver of the CPC reflector. Arrangements with four, five, and six tubes are considered. Overall, the four-tube scenario presents the worst performance of all, followed by the five-tube case. In general, the six-tube configuration is better. Nevertheless, important differences can be observed depending on the specific arrangement of tubes. The six-tube case surpasses the absorption rate of all the other configurations when the distance between tubes is extended. This configuration exhibits 27% increased yearly energy absorption with respect to the reference case and 47% with respect to the worst case scenario.
Genetic and Modifiable Risk Factors Contributing to Cisplatin-induced Toxicities
Authors: Trendowski Matthew R. , El Charif Omar , Dinh Paul C. , Travis Lois B. , Dolan M. Eileen
Published: October 2018

Effective administration of traditional cytotoxic chemotherapy is often limited by off-target toxicities. This clinical dilemma is epitomized by cisplatin, a platinating agent, which has potent antineoplastic activity due to its affinity for DNA and other intracellular nucleophiles. Despite its efficacy against many adult-onset and pediatric malignancies, cisplatin elicits multiple off-target toxicities that can not only severely impact a patient's quality of life but also lead to dose reductions or the selection of alternative therapies that can ultimately affect outcomes. Without an effective therapeutic measure by which to successfully mitigate many of these symptoms, there have been attempts to identify a priori those individuals who are more susceptible to developing these sequelae through studies of genetic and nongenetic risk factors. Older age is associated with cisplatin-induced ototoxicity, neurotoxicity, and nephrotoxicity. Traditional genome-wide association studies have identified single-nucleotide polymorphisms in ACYP2 and WFS1 associated with cisplatin-induced hearing loss. However, validating associations between specific genotypes and cisplatin-induced toxicities with enough stringency to warrant clinical application remains challenging. This review summarizes the current state of knowledge with regard to specific adverse sequelae following cisplatin-based therapy, with a focus on ototoxicity, neurotoxicity, nephrotoxicity, myelosuppression, and nausea/emesis. We discuss variables (genetic and nongenetic) contributing to these detrimental toxicities and currently available means to prevent or treat their occurrence.
X-Aptamer Technology Identifies C4A and ApoB in Blood as Potential Markers for Schizophrenia
Authors: Walss-Bass Consuelo , Lokesh Ganesh L.R. , Dyukova Elena , Gorenstein David G. , Roberts David L. , Velligan Dawn , Volk David E.
Published: October 2018

The field of proteomics is rapidly gaining territory as a promising alternative to genomic approaches in the efforts to unravel the complex molecular mechanisms underlying schizophrenia and other psychiatric disorders. X-aptamer tech­nology has emerged as a novel proteomic approach for high-sensitivity analyses, and we hypothesized that this technology would identify unique molecular signatures in plasma samples from schizophrenia patients (n = 60) compared to controls (n = 20). Using a combinatorial library of X-aptamer beads, we developed a two-color flow cytometer-based approach to identify specific X-aptamers that bound with high specificity to each target group. Based on this, we synthesized two unique X-aptamer sequences, and specific proteins pulled down from the patient and control groups by these X-aptamers were identified by mass spectrometry. We identified two protein biomarkers, complement component C4A and ApoB, upregulated in plasma samples from schizophrenia patients. ELISA validation suggested that the observed differences in C4 levels in patients are likely due to the presence of the illness itself, while ApoB may be a marker of antipsychotic-induced alterations. These studies highlight the utility of the X-aptamer technology in the identification of biomarkers for schizophrenia that will advance our understanding of the pathophysiological mechanisms of this disorder.