bluuebunny/crossref_metadata_2025 huggingface dataset:
State-of-the-Art of Pressure Drop in Open-Cell Porous Foams: Review of Experiments and Correlations
Authors: Kumar Prashant , Topin Frédéric
Published: June 2017

Foam structures are a class of modern microporous media that possesses high thermal conductivity, large accessible specific surface area, and high porosities. Nowadays, industrial applications, such as filtration, heat exchange and chemical reaction, etc., utilize porous media such as open-cell foams. Knowledge of pressure drop induced by these foam matrices is essential for successful design and operation of high-performance industrial systems. The homogenized pressure drop data in the literature are widely dispersed (up two orders of magnitude) despite numerous researches has been conducted since two decades. Most of the empirical pressure drop correlations were derived using Ergun-like approach. In this view, a careful evaluation of empirical correlations as well as the relationship of intrinsic flow law characteristics (permeability and inertia coefficient) with morphological parameters is imperative. This paper presents the start-of-the-art of various pressure drop correlations as well as highlights the ambiguities and inconsistencies in various definitions of several key parameters. The applicability of the empirical correlations presented in the literature was examined by comparing them against numerically calculated pressure drop data of open-cell foams (metal and ceramic) for the porosities ranging from 0.60 up to 0.95. A comprehensive study has been conducted to identify the reasons of dispersed pressure drop data in the literature. Although substantial progress has been made in the field of fluid flow in open-cell foams, it is yet difficult to predict pressure drop data from a given set of morphological parameters.
Nondimensional Parameter for Characterization of Wall Shear Stress From Underexpanded Axisymmetric Impinging Jets
Authors: Fillingham Patrick , Murali Harikrishnan , Novosselov Igor V.
Published: June 2017

Wall shear stress is characterized for underexpanded axisymmetric impinging jets for the application of aerodynamic particle resuspension from a surface. Analysis of the flow field resulting from normally impinging axisymmetric jets is conducted using computational fluid dynamics (CFD). A normally impinging jet is modeled with a constant area nozzle while varying the height to diameter ratio (H/D) and the inlet pressures. Schlieren photography is used to visualize the density gradient of the flow field for validation of the CFD. A dimensionless jet parameter (DJP) is developed to describe flow regimes and characterize shear stress. The DJP is defined as being proportional to the jet pressure ratio divided by the H/D ratio squared. Maximum wall shear stress is examined as a function of DJP with three distinct regimes: (i) subsonic impingement (DJP < 1), (ii) transitional (1 < DJP < 2), and (iii) supersonic impingement (DJP > 2). It is observed that wall shear stress is limited to a finite value due to jet energy dissipation in shock structures, which become a dominant dissipation mechanism in the supersonic impingement regime. Additionally, the formation of shock structures in the wall flow was observed for DJP > 2, resulting in difficulties with dimensionless analysis. In subsonic impingement and transitional regimes, equations as a function of the DJP are obtained for the maximum wall shear stress magnitude, maximum shear stress location, and shear stress decay. Using these relationships, wall shear stress can be predicted at all locations along the impingement surface.
Cyclic Sheet Metal Test Comparison and Parameter Calibration for Springback Prediction of Dual-Phase Steel Sheets
Authors: Gu Bin , He Ji , Li Shuhui , Chen Yuan , Li Yongfeng
Published: June 2017

Springback is an important issue for the application of advanced high-strength steels (AHSS) in the automobile industry. Various studies have shown that it is an effective way to predict springback by using path-dependent material models. The accuracy of these material models greatly depends on the experimental test methods as well as material parameters calibrated from these tests. The present cyclic sheet metal test methods, like uniaxial tension–compression test (TCT) and cyclic shear test (CST), are nonstandard and various. The material parameters calibrated from these tests vary greatly from one to another, which makes the usage of material parameters for the accurate prediction of springback more sophisticated even when the advanced material model is available in commercial software. The focus of this work is to compare the springback prediction accuracy by using the material parameters calibrated from tension–compression test or cyclic shear test, and to further clarify the usage of those material parameters in application. These two types of nonstandard cyclic tests are successfully carried out on a same test platform with different specimen geometries. One-element models with corresponding tension–compression or cyclic shear boundary conditions are built, respectively, to calibrate the parameters of the modified Yoshida–Uemori (YU) model for these two different tests. U-bending process is performed for springback prediction comparison. The results show, for dual phase steel (DP780), the work hardening stagnation is not evident by tension–compression tests at all the prestrain levels or by cyclic shear test at small prestrain γ = 0.20 but is significantly apparent by cyclic shear tests at large prestrain γ = 0.38, 0.52, 0.68, which seems to be a prestrain-dependent phenomenon. The material parameters calibrated from different types of cyclic sheet metal tests can vary greatly, but it gives slight differences of springback prediction for U-bending by utilizing either tension–compression test or cyclic shear test.
Review of Kinematics for Minimally Invasive Surgery and Tele-Echography Robots
Authors: Nouaille L. , Laribi M. A. , Nelson C. A. , Zeghloul S. , Poisson G.
Published: June 2017

This paper deals with the survey of kinematic structures adapted to specific medical robots: minimally invasive surgery (MIS) and tele-echography. The large diversity of kinematic architectures that can be found in medical robotics leads us to perform a statistical analysis to inform and guide design of medical robots. Safety constraints and some considerations in design evolution of medical robots are presented in this paper. First, we describe the spectrum of medical robots in minimally invasive surgery and tele-echography applications and particularly the variety of kinematic architectures used. We present the robots and their kinematic architectures and highlight differences that occur in each medical application. We perform a statistical analysis which can serve as a resource in topological synthesis for each specific medical application. Safety is an important specification in medical robotics, and for that reason we show the means used to take into account this constraint. This study demonstrates that the nature of medical robots implies specific requirements leading to different kinematic structures. The statistical analysis gives information on choice of kinematic structures for medical applications (minimally invasive surgery and echography). The safety constraint as well as the interaction between doctor and robot leads to investigate new mechanical solutions to enhance medical robot safety and compliance. We expect that this paper will serve as a significant resource and help the design of future medical robots.
A Human Thermoregulation Simulator for Calibrating Water-Perfused Cooling Pad Systems for Therapeutic Hypothermia
Authors: Chacko Priya S. E. , Seifi Ali , Diller Kenneth R.
Published: June 2017

The induction of a mild reduction in body core temperature has been demonstrated to provide neuroprotection for patients who have suffered a medical event resulting in ischemia to the brain or vital organs. Temperatures in the range of 32–34 °C provide the required level of protection and can be produced and maintained by diverse means for periods of days. Rewarming from hypothermia must be conducted slowly to avoid serious adverse consequences and usually is performed under control of the thermal therapeutic device based on a closed-loop feedback strategy based on the patient's core temperature. Given the sensitivity and criticality of this process, it is important that the device control system be able to interact with the human thermoregulation system, which itself is highly nonlinear. The therapeutic hypothermia device must be calibrated periodically to ensure that its performance is accurate and safe for the patient. In general, calibration processes are conducted with the hypothermia device operating on a passive thermal mass that behaves much differently than a living human. This project has developed and demonstrated an active human thermoregulation simulator (HTRS) that embodies major governing thermal functions such as central metabolism, tissue conduction, and convective transport between the core and the skin surface via the flow of blood and that replicates primary dimensions of the torso. When operated at physiological values for metabolism and cardiac output, the temperature gradients created across the body layers and the heat exchange with both an air environment and a clinical water-circulating cooling pad system match that which would occur in a living body. Approximately two-thirds of the heat flow between the core and surface is via convection rather than conduction, highlighting the importance of including the contribution of blood circulation to human thermoregulation in a device designed to calibrate the functioning of a therapeutic hypothermia system. The thermoregulation simulator functions as anticipated for a typical living patient during both body cooling and warming processes. This human thermoregulatory surrogate can be used to calibrate the thermal function of water-perfused cooling pads for a hypothermic temperature management system during both static and transient operation.
Experimental Investigation on Unstable Vibration Characteristics of Plates and Drag Torque in Open Multiplate Wet Clutch at High Circumferential Speed
Authors: Hou Shiyang , Hu Jibin , Peng Zengxiong
Published: June 2017

The drag torque caused by the viscous shear in open multiplate wet clutches has been studied in most available literature whose focus is placed on low circumferential speed. However, the drag torque increases drastically in the high circumferential speed range. The underlying physical principles and the influencing factors of the drag torque at high speed are still indeterminate. The present study aims to experimentally investigate the characteristics of the wobbling vibrations of plates and to characterize the effects of average clearance, flow rate of lubricant, shifting condition, and the number of friction interfaces on the drag torque at high circumferential speed. The result of the experiment reveals that the friction plate (FP) starts to wobble periodically at low circumferential speed, though the effect is insignificant. The dominant frequency of plate wobbling movements increases with the input speed. When wobbling vibrations of plates become unstable, the wobble gradually becomes nonlinear. The experiments confirm that the mechanical contacts between plates during the unstable wobbling vibration result in the drag torque rise at high circumferential speed. At high speed, the supplying flow rate of the lubricant influences the drag torque values. The rotation of separator plates (SPs) brings forward the torque rise and makes the drag torque rise smoother. By reducing the number of interfaces, the drag torque rise is delayed and the magnitude becomes smaller. Finally, a four-stage drag torque characteristic curve is illustrated to show the dominant factors of drag torque at different stages.
Effect of Temperature Jump on Nonequilibrium Entropy Generation in a MOSFET Transistor Using Dual-Phase-Lagging Model
Authors: Echouchene Fraj , Belmabrouk Hafedh
Published: June 2017

This paper investigates the effect of temperature-jump boundary condition on nonequilibrium entropy production under the effect of the dual-phase-lagging (DPL) heat conduction model in a two-dimensional sub-100 nm metal-oxide-semiconductor field effect transistor (MOSFET). The transient DPL model is solved using finite element method. Also, the influences of the governing parameters on global entropy generation for the following cases—(I) constant applied temperature, (II) temperature-jump boundary condition, and (III) a realistic MOSFET with volumetric heat source and adiabatic boundaries—are discussed in detail and depicted graphically. The analysis of our results indicates that entropy generation minimization within a MOSFET can be achieved by using temperature-jump boundary condition and for low values of Knudsen number. A significant reduction of the order of 85% of total entropy production is observed when a temperature-jump boundary condition is adopted.
The
Aspergillus fumigatus
CrzA Transcription Factor Activates Chitin Synthase Gene Expression during the Caspofungin Paradoxical Effect
Authors: Ries Laure Nicolas Annick , Rocha Marina Campos , de Castro Patrícia Alves , Silva-Rocha Rafael , Silva Roberto Nascimento , Freitas Fernanda Zanolli , de Assis Leandro José , Bertolini Maria Célia , Malavazi Iran , Goldman Gustavo H.
Published: June 2017

Aspergillus fumigatus
is an opportunistic fungal pathogen that causes invasive aspergillosis (IA), a life-threatening disease in immunocompromised humans. The echinocandin caspofungin, adopted as a second-line therapy in combating IA, is a β-1,3-glucan synthase inhibitor, which, when used in high concentrations, reverts the anticipated
A. fumigatus
growth inhibition, a phenomenon called the “caspofungin paradoxical effect” (CPE). The CPE has been widely associated with increased chitin content in the cell wall due to a compensatory upregulation of chitin synthase-encoding genes. Here, we demonstrate that the CPE is dependent on the cell wall integrity (CWI) mitogen-activated protein kinase MpkA
MPK1
and its associated transcription factor (TF) RlmA
RLM1
, which regulate chitin synthase gene expression in response to different concentrations of caspofungin. Furthermore, the calcium- and calcineurin-dependent TF CrzA binds to and regulates the expression of specific chitin synthase genes during the CPE. These results suggest that the regulation of cell wall biosynthetic genes occurs by several cellular signaling pathways. In addition, CrzA is also involved in cell wall organization in the absence of caspofungin. Differences in the CPE were also observed between two
A. fumigatus
clinical isolates, which led to the identification of a novel basic leucine zipper TF, termed ZipD. This TF functions in the calcium-calcineurin pathway and is involved in the regulation of cell wall biosynthesis genes. This study therefore unraveled additional mechanisms and novel factors governing the CPE response, which ultimately could aid in developing more effective antifungal therapies.

IMPORTANCE
Systemic
Aspergillus fumigatus
infections are often accompanied by high mortality rates. The fungal cell wall is important for infection as it has immunomodulatory and immunoevasive properties. Paradoxical growth of
A. fumigatus
in the presence of high concentrations of the cell wall-disturbing agent caspofungin has been observed for more than a decade, although the mechanistic nature of this phenomenon remains largely uncharacterized. Here, we show that the CWI pathway components MpkA and RlmA as well as the calcium/calcineurin-responsive transcription factor CrzA regulate the expression of cell wall biosynthetic genes during the caspofungin paradoxical effect (CPE). Furthermore, an additional, novel calcium/calcineurin-responsive transcription factor was identified to play a role in cell wall biosynthesis gene expression during the CPE. This work paints a crucial role for calcium metabolism in the CPE and provides further insight into the complex regulation of cell wall biosynthesis, which could ultimately lead to the development of more efficient antifungal therapies.
Translational Control of the SigR-Directed Oxidative Stress Response in
Streptomyces
via IF3-Mediated Repression of a Noncanonical GTC Start Codon
Authors: Feeney Morgan A. , Chandra Govind , Findlay Kim C. , Paget Mark S. B. , Buttner Mark J.
Published: June 2017

The major oxidative stress response in
Streptomyces
is controlled by the sigma factor SigR and its cognate antisigma factor RsrA, and SigR activity is tightly controlled through multiple mechanisms at both the transcriptional and posttranslational levels. Here we show that
sigR
has a highly unusual GTC start codon and that this leads to another level of SigR regulation, in which SigR translation is repressed by translation initiation factor 3 (IF3). Changing the GTC to a canonical start codon causes SigR to be overproduced relative to RsrA, resulting in unregulated and constitutive expression of the SigR regulon. Similarly, introducing IF3* mutations that impair its ability to repress SigR translation has the same effect. Thus, the noncanonical GTC
sigR
start codon and its repression by IF3 are critical for the correct and proper functioning of the oxidative stress regulatory system.
sigR
and
rsrA
are cotranscribed and translationally coupled, and it had therefore been assumed that SigR and RsrA are produced in stoichiometric amounts. Here we show that RsrA can be transcribed and translated independently of SigR, present evidence that RsrA is normally produced in excess of SigR, and describe the factors that determine SigR-RsrA stoichiometry.

IMPORTANCE
In all sigma factor-antisigma factor regulatory switches, the relative abundance of the two proteins is critical to the proper functioning of the system. Many sigma-antisigma operons are cotranscribed and translationally coupled, leading to a generic assumption that the sigma and antisigma factors are produced in a fixed 1:1 ratio. In the case of
sigR
-
rsrA
, we show instead that the antisigma factor is produced in excess over the sigma factor, providing a buffer to prevent spurious release of sigma activity. This excess arises in part because
sigR
has an extremely rare noncanonical GTC start codon, and as a result, SigR translation initiation is repressed by IF3. This finding highlights the potential significance of noncanonical start codons, very few of which have been characterized experimentally. It also emphasizes the limitations of predicting start codons using bioinformatic approaches, which rely heavily on the assumption that ATG, GTG, and TTG are the only permissible start codons.
A qualitative analysis of the Three Good Things intervention in healthcare workers
Authors: Rippstein-Leuenberger Karin , Mauthner Oliver , Bryan Sexton J , Schwendimann Rene
Published: June 2017

Background

Intensive care unit (ICU) personnel have an elevated prevalence of job-related burn-out and post-traumatic stress disorder, which can ultimately impact patient care. To strengthen healthcare workers’ skills to deal with stressful events, it is important to focus not only on minimising suffering but also on increasing happiness, as this entails many more benefits than simply feeling good. Thus, the purpose of this study was to explore the content of the ‘good things’ reported by healthcare workers participating in the ‘Three Good Things’ intervention.

Methods

In a tertiary care medical centre, a sample of 89 neonatal ICU (NICU) healthcare professionals registered for the online intervention. Of these, 32 individuals eventually participated fully in the 14-day online Three Good Things intervention survey. Daily emails reminded participants to reflect on and respond to the questions: “What are the three things that went well today?” and “What was your role in bringing them about?” To analyse their responses, we applied a thematic analysis, which was guided by our theoretical understanding of resilience.

Results

Involving more than 1300 statements, the Three Good Things responses of the 32 study participants, including registered nurses, physicians and neonatal nurse practitioners, led to the identification of three main themes: (1) having a good day at work; (2) having supportive relationships and (3) making meaningful use of self-determined time.

Conclusions

The findings show the personal and professional relevance of supportive relationships strengthened by clear communication and common activities that foster positive emotions. The Three Good Things exercise acknowledges the importance of self-care in healthcare workers and appears to promote well-being, which might ultimately strengthen resilience.
New quantitative features for the morphological differentiation of abnormal lymphoid cell images from peripheral blood
Authors: Puigví Laura , Merino Anna , Alférez Santiago , Acevedo Andrea , Rodellar José
Published: June 2017

Aims

This work aims to propose a set of quantitative features through digital image analysis for significant morphological qualitative features of different cells for an objective discrimination among reactive, abnormal and blast lymphoid cells.

Methods

Abnormal lymphoid cells circulating in peripheral blood in chronic lymphocytic leukaemia, B-prolymphocytic leukaemia, hairy cell leukaemia, splenic marginal zone lymphoma, mantle cell lymphoma, follicular lymphoma, T-prolymphocytic leukaemia, T large granular lymphocytic leukaemia and Sézary syndrome, normal, reactive and blast lymphoid cells were included. From 325 patients, 12 574 cell images were obtained and 2676 features (27 geometric and 2649 related to colour and texture) were extracted and analysed.

Results

We analysed the 20 most relevant features for the morphological differentiation of the 12 lymphoid cell groups under study. Most of them showed significant differences: 19 comparing follicular and mantle cells, 18 for blast and reactive cells, 17 for Sézary cells and T prolymphocytes and 16 for B and T prolymphocytes and 16 for villous lymphocytes. Moreover, a total of five quantitative features were significant for the discrimination among reactive and the set of abnormal lymphoid cells included.

Conclusions

Image analysis may assist in quantifying cell morphology turning qualitative data into quantitative values. New cytological variables were established based on geometric and colour/texture features to contribute to a more accurate and objective morphological assessment of lymphoid cells and their association with flow cytometry methods may be interesting to explore in the next future.
Unsymmetrically functionalized 5,5″-diaryl- and 5,6,5″-triaryl-2,2′:6′,2″-terpyridines: an efficient synthetic route and photophysical properties
Authors: Krinochkin Alexey P. , Kopchuk Dmitry S. , Khasanov Albert F. , Chepchugov Nikolay V. , Kovalev Igor S. , Santra Sougata , Zyryanov Grigory V. , Majee Adinath , Rusinov Vladimir L. , Chupakhin Oleg N.
Published: June 2017

An efficient approach for the synthesis of 5,5″- or 5,6,5″-aryl substituted 2,2′:6′,2″-terpyridines, bearing an anneleted cyclopentene unit in one of the side-chain pyridine rings for the improved solubility in organic solvents, via their 1,2,4-triazine analogues has been developed. By using this approach, various aromatic substituents were introduced in the 2,2′:6′,2″-terpyridine core. Depending on the nature of the aromatic substituents, the obtained terpyridines exhibited an intense emission in a range of ca. 344–394 nm in acetonitrile solutions. For the most representative compounds, pronounced bathochromic shifts in both absorption and emission spectra were observed compared with previously reported substituted terpyridines.
Accelerated hydrolysis of boronic acid in a modified poly(amidoamine) dendrimer: identification of a factor leading to the production of an impurity in boronic acid containing poly(amidoamine) dendrimers
Authors: Tsai Ching-Hua , Fang Yu-Wen , Chen Hui-Ting , Kao Chai-Lin
Published: June 2017

The preparation of boronic acid containing dendrimers is still a difficult task in dendrimer chemistry. In this investigation, an unanticipated hydrolysis product (4) was identified during the preparation of (G:2)-PAMAM-dendri-(4-phenyl boronic acid)14 (3) by acquiring its 1H NMR, 13C NMR, and UV–vis absorption spectra and IR spectra and comparing them with those of 4-hydroxylbenzoic acid (5). Furthermore, an Alizarin Red S staining analysis, ICP-MS, and 11B NMR spectrum indicated the lack of boronic acid in 4. Finally, treatment of 3 with hydrogen peroxide gave a product that was determined to be identical to dendrimer 4. By analyzing the formation of 4 under various conditions, the presence of numerous primary amines in a PAMAM dendrimer did accelerate the hydrolysis of peripheral boronic acid. This investigation revealed an apparent intrinsic problem that needs to be overcome during the preparation of boronic acid containing dendrimers and related boronic acid containing macromolecules.
LONG RANGE DEPENDENCE AND STRUCTURAL BREAKS IN THE GOLD MARKETS
Authors: CHONG TERENCE TAI LEUNG , LU CHENXI , CHAN WING HONG
Published: June 2017

The price of gold and its determining factors have been studied extensively in the literature. However, there is a lack of research on structural break in the long memory of the gold markets. This paper examines the long memory properties of gold prices. In particular, it attempts to test the stability of the long range dependence of gold returns and volatility. The results suggest that long memory exists in gold returns and volatility, and that the volatility of daily gold futures returns can be characterized by a hyperbolic decaying long memory process. Three episodes of structural breaks are found.
Free polaron energy levels in AlyGa1−yN/AlxGa1−xN triangle quantum well structures
Authors: Pan Hong Yu , Zhao Feng Qi
Published: June 2017

In this work, a variational method is used to examine the problems relevant to the free polaron energy spectrum in a wurtzite Al[Formula: see text]Ga[Formula: see text]N/Al[Formula: see text]Ga[Formula: see text]N triangle quantum well structure. The numerical calculations for the ground state energy, transition energy and polaron energy shifts as the functions of well-width [Formula: see text] and composition [Formula: see text] are carried out by considering the anisotropies of the parameters, such as the optical phonon frequency, dielectric constant and electron effective mass, as well as their observed changes with coordinate [Formula: see text] in this system. The research results show that the polaron energy shift caused by the electron–optical phonon interaction is large, and leads to an obvious energy decrease in the Al[Formula: see text]Ga[Formula: see text]N/Al[Formula: see text]Ga[Formula: see text]N triangular quantum well structure. The contribution of the confined phonon is found to increase with the increasing of the well-width and composition [Formula: see text], while that of the half space phonon is observed to decrease with the increasing of the well-width and composition [Formula: see text]. The total contribution of the phonon increases with the increasing composition [Formula: see text], while a minimum is found to occur to the total contribution of the phonon during the decreasing process with the well-width. As the [Formula: see text] increases, the free polaron energies and transition energies decrease. Meanwhile, with the increasing of the composition [Formula: see text], the energy and transition energy are found to be increased. In the Al[Formula: see text]Ga[Formula: see text]N/Al[Formula: see text]Ga[Formula: see text]N triangular quantum well structure, the trends of the free polaron energy, transition energy and polaron energy shifts with the well-width and composition [Formula: see text] are found to be similar to those in the GaN/Al[Formula: see text]Ga[Formula: see text]N square quantum well structure. However, the corresponding values in the triangular quantum well structure are obviously greater than those in the square quantum well structure.
Thomas–Fermi approximation for the equation of state of nuclear matter: A semi-classical approach from the Landau Fermi-Liquid theory
Authors: Ghazanfari Mojarrad M. , Mousavi Khoroshtomi S. K.
Published: June 2017

The equation of state (EOS) of nuclear matter is investigated in a semi-classical mean-field (MF) approach. Starting from the phase-space NN-interaction of Myers and Swiatecki [Nucl. Phys. A 601 (1996) 141], the EOS of nuclear matter by the Thomas–Fermi approximation is derived. A self-consistent semi-classical approach is presented by employing the Landau Fermi-Liquid theory (LFT). In our statistical approach, the phase-space occupation number can be expressed in terms of an extended effective mass which is affected by both temperature and nucleonic density. Accordingly, an explicit expression of the nucleonic chemical potential inside the nucleonic occupation number can be obtained. Special attention is also devoted to the density dependence of the nuclear symmetry free energy at different temperatures. The results of this model are compared with other theoretical predictions.
Multi-Scale Failure Analysis of Transmission Towers Under Downburst Loading
Authors: Wang F. Y. , Xu Y. L. , Qu W. L.
Published: June 2017

Collapse of transmission towers due to downbursts is often initiated by local failure of key structural members, while the local failure of key structural members is related to local material and geometrical nonlinearities. This paper presents a multi-scale finite element (FE) model for the failure analysis of transmission towers under downburst-induced wind loading. The potential local failure areas of the tower are modeled by shell or solid elements, and the remaining parts by beam elements. In this way, the failure of the tower can be accurately simulated on the one hand and the computational effort can be reduced on the other hand. This paper first introduces how to determine the downburst-induced wind loading on transmission towers. Both the conventional beam and multi-scale FE models of the transmission tower are then developed and used in the failure analysis. A comparison of the failure results obtained by the two FE models show that the multi-scale FE model can effectively simulate the stress concentration of angle members around the bolt connections and the cross-section plastic collapse of key structural members, leading to a different failure pattern for the tower from the conventional FE method. It is suggested that the multi-scale FE model should be used for better accuracy in the failure analysis of transmission towers under downburst loading.
Non-central limit theorems for quadratic functionals of Hermite-driven long memory moving average processes
Authors: Diu Tran T. T.
Published: June 2017

Let [Formula: see text] denote a Hermite process of order [Formula: see text] and self-similarity parameter [Formula: see text]. Consider the Hermite–driven moving average process [Formula: see text] In the special case of [Formula: see text], [Formula: see text] is the non-stationary Hermite Ornstein–Uhlenbeck process of order [Formula: see text]. Under suitable integrability conditions on the kernel [Formula: see text], we prove that as [Formula: see text], the normalized quadratic functional [Formula: see text] where [Formula: see text], converges in the sense of finite-dimensional distribution to the Rosenblatt process of parameter [Formula: see text], up to a multiplicative constant, irrespective of self-similarity parameter whenever [Formula: see text]. In the Gaussian case [Formula: see text], our result complements the study started by Nourdin et al. in [10], where either central or non-central limit theorems may arise depending on the value of self-similarity parameter. A crucial key in our analysis is an extension of the connection between the classical multiple Wiener–Itô integral and the one with respect to a random spectral measure (initiated by Taqqu (1979)), which may be independent of interest.
Using High Performance Computing for Liquefaction Hazard Assessment with Statistical Soil Models
Authors: Chen Jian , Takeyama Tomohide , O-Tani Hideyuki , Fujita Kohei , Motoyama Hiroki , Hori Muneo
Published: June 2017

Conventional methods for liquefaction assessment using engineering indices such as Factor of safety against Liquefaction (FL) tend to overestimate liquefaction hazards. The soil dynamics analysis-based assessment with automatic modeling is more rational and robust. Soil properties are known for large uncertainties. Rather than deterministic soil models, statistical models for soil parameters should be considered. With automatic modeling, a large number of statistic models can be generated without difficulty. The problem becomes how to assess liquefaction hazard with statistic models in an efficient way. Using high performance computing, we develop an efficient liquefaction assessment method for statistical modeling of soils. A high parallel efficiency can be achieved and a large number of statical models of the order of 104 can be simulated within a reasonable time span. The method developed in this paper can be used as an efficient tool for unravelling critical parameters of soil liquefaction.
Application of partial least squares regression for identifying multivariate geochemical anomalies in stream sediment data from Northwestern Hunan, China
Authors: Kun Wang , Keyan Xiao , Nan Li , Yuan Cong , Shengmiao Li
Published: June 2017

The Northwestern Hunan in China is a prospective area for Mississippi Valley-type (MVT) Pb-Zn mineralization similar to the large Huayuan Pb-Zn deposits, which contains tens of millions of tons of resources. Based on the characteristics of the host strata, geochemical data in the Qingxudong Formation were analysed and summarized using Pearson correlation coefficients, including both ore-forming oxides and trace elements. Significant correlation pairs related to Pb-Zn mineralization are extracted. Partial Least Squares Regression (PLSR) was applied separately to the rock-forming oxides and trace elements to extract integrated geochemical anomalies. Anomalies showing an association of rock-forming oxides extracted using PLSR largely coincide with mapped strata, faults, ore deposits and elemental correlations in ore-bearing stratum, indicating the superiority of PLSR; The trace element associations extracted by PLSR are similar to those extracted using the cluster method; we can directly map the former but not the latter. Therefore, the analyses of multivariate geochemical anomalies using PLSR can provide significant information relevant to exploration for mineral deposits.
How to choose a conference
Authors: Hunsucker Andrew J.
Published: June 2017

Bigger is not always better when building an academic reputation.
Forests, trees, and false dichotomies
Authors: Miller Stephen
Published: June 2017

As the gap between research and productization continues to narrow, traditional labels may no longer apply.
Being an open entrepreneur
Authors: Gibb Alicia , Seidle Nathan
Published: June 2017

What does it mean to be an entrepreneur making open source hardware? An open entrepreneur has parallels to being an entrepreneur of any company, but there are also advantages that are often overlooked.
Building a business based on the life you want to lead
Authors: Wang Chris "Akiba" , Plucinski Jacinta
Published: June 2017

Running a business and living the lifestyle you want can be seen as mutually exclusive. Maintaining the right balance, while meeting the changing goals of both, can be seen as a talent. But shifting focus away from the bottom line can lead to a better outcome, professionally and personally. Two entrepreneurs share their ongoing journey toward mastering this art.
I, entrepreneur
Authors: Khan Numair , Penu Alexandru , Dickerson Thomas , Liukas Linda , Jung-Harada Cesar , Bhattacharya Sam
Published: June 2017

Five, diverse entrepreneurs from around the world share a common ambition of social good. Here they detail how they entered the world of startups.
Cancer: from biology to computer science
Authors: Hosny Abdelrahman
Published: June 2017

Cancer research has been at the heart of life sciences for the past few decades. Since genetics play an important role in most cancers, computational methods are crucial in understanding the development of the disease.
Stellar Model Chromospheres and Spectroscopic Diagnostics
Authors: Linsky Jeffrey L.
Published: June 2017

The discovery of exoplanets and the desire to understand their atmospheric chemical composition and habitability provides a new rationale for understanding the radiation from X-rays to radio wavelengths emitted by their host stars. Semiempirical models of stellar atmospheres that include accurate treatment of radiative transfer of all important atoms, ions, and molecules provide the essential basis for understanding a star's emitted radiation that is our main data source for characterizing a star and the radiation environment of its exoplanets. In Solar-type and cooler stars, the ultraviolet and extreme ultraviolet radiation formed in their chromospheres and transition regions drive the photochemistry in exoplanet atmospheres. In this review, I describe and critique the development of semiempirical static and time-dependent models of the chromospheres and transition regions of the Sun and cooler stars as well as the spectroscopic diagnostics upon which these models are based. The related topics of stellar coronae and winds and their theoretical bases are beyond the scope of this review.
The intestinal-renal axis for arginine synthesis is present and functional in the neonatal pig
Authors: Marini Juan C. , Agarwal Umang , Robinson Jason L. , Yuan Yang , Didelija Inka C. , Stoll Barbara , Burrin Douglas G.
Published: June 2017

The intestinal-renal axis for endogenous arginine synthesis is an interorgan process in which citrulline produced in the small intestine is utilized by the kidney for arginine synthesis. The function of this axis in neonates has been questioned because during this period the enzymes needed for arginine synthesis argininosuccinate synthase (ASS1) and lyase (ASL) are present in the gut. However, evidence of high plasma citrulline concentrations in neonates suggests otherwise. We quantified in vivo citrulline production in premature (10 days preterm), neonatal (7 days old), and young pigs (35 days old) using citrulline tracers. Neonatal pigs had higher fluxes (69 µmol·kg−1·h−1, P < 0.001) than premature and young pigs (43 and 45 µmol·kg−1·h−1, respectively). Plasma citrulline concentration was also greater in neonatal pigs than in the other age groups. We also determined the site of synthesis and utilization of citrulline in neonatal and young pigs by measuring organ balances across the gut and the kidney. Citrulline was released from the gut and utilized by the kidney in both neonatal and young pigs. The abundance and localization of the enzymes involved in the synthesis and utilization were determined in intestinal and kidney tissue. Despite the presence of ASS1 and ASL in the neonatal small intestine, the lack of colocalization with the enzymes that produce citrulline results in the release of citrulline by the PDV and its utilization by the kidney to produce arginine. In conclusion, the intestinal-renal axis for arginine synthesis is present in the neonatal pig.
High glucose increases action potential firing of catecholamine neurons in the nucleus of the solitary tract by increasing spontaneous glutamate inputs
Authors: Roberts Brandon L. , Zhu Mingyan , Zhao Huan , Dillon Crystal , Appleyard Suzanne M.
Published: June 2017

Glucose is a crucial substrate essential for cell survival and function. Changes in glucose levels impact neuronal activity and glucose deprivation increases feeding. Several brain regions have been shown to respond to glucoprivation, including the nucleus of the solitary tract (NTS) in the brain stem. The NTS is the primary site in the brain that receives visceral afferent information from the gastrointestinal tract. The catecholaminergic (CA) subpopulation within the NTS modulates many homeostatic functions including cardiovascular reflexes, respiration, food intake, arousal, and stress. However, it is not known if they respond to changes in glucose. Here we determined whether NTS-CA neurons respond to changes in glucose concentration and the mechanism involved. We found that decreasing glucose concentrations from 5 mM to 2 mM to 1 mM, significantly decreased action potential firing in a cell-attached preparation, whereas increasing it back to 5 mM increased the firing rate. This effect was dependent on glutamate release from afferent terminals and required presynaptic 5-HT3Rs. Decreasing the glucose concentration also decreased both basal and 5-HT3R agonist-induced increase in the frequency of spontaneous glutamate inputs onto NTS-CA neurons. Low glucose also blunted 5-HT-induced inward currents in nodose ganglia neurons, which are the cell bodies of vagal afferents. The effect of low glucose in both nodose ganglia cells and in NTS slices was mimicked by the glucokinase inhibitor glucosamine. This study suggests that NTS-CA neurons are glucosensing through a presynaptic mechanism that is dependent on vagal glutamate release, 5-HT3R activity, and glucokinase.
Different roles for inhibition in the rhythm-generating respiratory network
Authors: Harris Kameron Decker , Dashevskiy Tatiana , Mendoza Joshua , Garcia Alfredo J. , Ramirez Jan-Marino , Shea-Brown Eric
Published: June 2017

Unraveling the interplay of excitation and inhibition within rhythm-generating networks remains a fundamental issue in neuroscience. We use a biophysical model to investigate the different roles of local and long-range inhibition in the respiratory network, a key component of which is the pre-Bötzinger complex inspiratory microcircuit. Increasing inhibition within the microcircuit results in a limited number of out-of-phase neurons before rhythmicity and synchrony degenerate. Thus unstructured local inhibition is destabilizing and cannot support the generation of more than one rhythm. A two-phase rhythm requires restructuring the network into two microcircuits coupled by long-range inhibition in the manner of a half-center. In this context, inhibition leads to greater stability of the two out-of-phase rhythms. We support our computational results with in vitro recordings from mouse pre-Bötzinger complex. Partial excitation block leads to increased rhythmic variability, but this recovers after blockade of inhibition. Our results support the idea that local inhibition in the pre-Bötzinger complex is present to allow for descending control of synchrony or robustness to adverse conditions like hypoxia. We conclude that the balance of inhibition and excitation determines the stability of rhythmogenesis, but with opposite roles within and between areas. These different inhibitory roles may apply to a variety of rhythmic behaviors that emerge in widespread pattern-generating circuits of the nervous system.

NEW & NOTEWORTHY The roles of inhibition within the pre-Bötzinger complex (preBötC) are a matter of debate. Using a combination of modeling and experiment, we demonstrate that inhibition affects synchrony, period variability, and overall frequency of the preBötC and coupled rhythmogenic networks. This work expands our understanding of ubiquitous motor and cognitive oscillatory networks.
Diffusion-weighted tractography in the common marmoset monkey at 9.4T
Authors: Schaeffer David J. , Adam Ramina , Gilbert Kyle M. , Gati Joseph S. , Li Alex X. , Menon Ravi S. , Everling Stefan
Published: June 2017

Although significant progress has been made in mapping white matter connections in the marmoset brain using ex vivo tracing techniques, the application of in vivo virtual dissection of major white matter fiber tracts has been established by few studies in the marmoset literature. Here, we demonstrate the feasibility of whole-brain diffusion-weighted tractography in anesthetized marmosets at ultrahigh-field MRI (9.4T) and propose protocols for isolating nine major white matter fiber tracts in the marmoset brain.
The Role of Free Radicals in Hemolytic Toxicity Induced by Atmospheric‐Pressure Plasma Jet
Authors: Baik Ku Youn , Huh Yoon Ho , Kim Yong Hee , Kim Jeongho , Kim Min Su , Park Hun-Kuk , Choi Eun Ha , Park Byoungchoo
Published: June 2017

Atmospheric‐pressure plasma (APP) has received attention due to its generation of various kinds of reactive oxygen/nitrogen species (ROS/RNS). The controllability, as well as the complexity, is one of the strong points of APP in various applications. For biological applications of this novel method, the cytotoxicity should be estimated at various levels. Herein, we suggest red blood cell (RBC) as a good cell model that is simpler than nucleated cells but much more complex than other lipid model systems. Air and N2 gases were compared to verify the main ROS/RNS in cytotoxicity, and microscopic and spectroscopic analyses were performed to estimate the damages induced on RBCs. The results shown here will provide basic information on APP‐induced cytotoxicity at cellular and molecular levels.
The Contribution of Geomagnetic Activity to Polar Ozone Changes in the Upper Atmosphere
Authors: Huang Cong , Huang Fuxiang , Zhang Xiaoxin , Liu Dandan , Lv Jingtian
Published: June 2017

Energetic particle precipitation (EPP) has significant impacts on ozone depletion in the polar middle atmosphere during geomagnetic activity. It is well known that solar ultraviolet (UV) radiation plays an important role in ozone generation. Therefore, it is interesting to compare the contributions of EPP and solar UV to ozone changes in the polar upper atmosphere. In this article, we use the annual average Ap index to denote the annual-mean magnitude of the geomagnetic activity, which is closely correlated with the EPP flux, and the annual average F10.7 index to denote the annual-mean magnitude of the solar radiation, which is somewhat related to the solar UV. We adopt the 5° zonal annual-mean ozone profile dataset to study the statistical characters between the ozone dataset and the Ap, F10.7 indices. Multiple regression analysis shows that the contributions of geomagnetic activity are not negligible and are of a similar order of magnitude as the solar UV radiation in the polar upper atmosphere (above 10 hPa). The results also show that high-speed solar-wind-stream-induced and coronal-mass-ejection-driven geomagnetic activity is of the same order of magnitude. There are interhemispheric differences according to our multiple regression analysis. We discuss the possible causes of these differences.
Risk of Fungal Infection to Dental Patients
Authors: Damasceno Jaqueline Lopes , Santos Rafael Aparecido dos , Barbosa Amir Horiquini , Casemiro Luciana Assirati , Pires Regina Helena , Martins Carlos Henrique Gomes
Published: June 2017

Fungi can cause various diseases, and some pathogenic fungi have been detected in the water of dental equipment. This environment offers suitable conditions for fungal biofilms to emerge, which can facilitate mycological contamination. This study verified whether the water employed in the dental units of two dental clinics at the University of Franca was contaminated with fungi. This study also evaluated the ability of the detected fungi to form biofilms. The high-revving engine contained the largest average amount of fungi, 14.93 ± 18.18 CFU/mL. The main fungal species verified in this equipment belonged to the generaAspergillusspp.,Fusariumspp.,Candidaspp., andRhodotorulaspp. Among the isolated filamentous fungi, only one fungus of the genusFusariumspp. did not form biofilms. As for yeasts, all theCandidaspp. isolates grew as biofilm, but none of theRhodotorulaspp. isolates demonstrated this ability. Given that professionals and patients are often exposed to water and aerosols generated by the dental procedure, the several fungal species detected herein represent a potential risk especially to immunocompromised patients undergoing dental treatment. Therefore, frequent microbiological monitoring of the water employed in dental equipment is crucial to reduce the presence of contaminants.