bluuebunny/crossref_metadata_2025 huggingface dataset:
A Spatially Explicit Method to Assess the Economic Suitability of a Forest Road Network for Timber Harvest in Steep Terrain
Authors: Bont Leo Gallus , Fraefel Marielle , Fischer Christoph
Published: March 2018

Despite relatively high road density in the forests of Switzerland, a large percentage of that road network does not fulfill best practice requirements. Before upgrading or rebuilding the road network, harvesting planners must first determine which areas have insufficient access. Traditional assessment methods tend to only report specific values such as road density. However, those values do not identify the exact parcels or areas that are inaccessible. Here, we present a model that assesses the economic suitability of each timbered parcel for wood-harvesting operations, including tree-felling and processing, and off- and on-road transport (hauling), based on the existing road network. The entire wood supply chain from forest (standing trees) to a virtual pile at the border of the planning unit was captured. This method was particularly designed for steep terrain and was tested in the Canton of Grisons in Switzerland. Compared with classical approaches, such as the road density concept, which only deliver average values, this new method enables planners to assess the development of a road network in a spatially explicit manner and to easily identify the reason and the location of shortcomings in the road network. Moreover, while other related spatially explicit approaches focus only on harvesting operations, the assessment method proposed here also includes limitations (road standards) of the road network.
Association of Overcrowding and Turnover with Self-Harm in a Swiss Pre-Trial Prison
Authors: Baggio Stéphanie , Gétaz Laurent , Tran Nguyen , Peigné Nicolas , Chacowry Pala Komal , Golay Diane , Heller Patrick , Bodenmann Patrick , Wolff Hans
Published: March 2018

Self-harm is a common issue in detention and includes both suicidal and non-suicidal behaviours. Beyond well-known individual risk factors, institutional factors such as overcrowding (i.e., when the prison population exceeds its capacity) and turnover (i.e., the rate at which the prison population is renewed), may also increase the risk of self-harm. However, these factors are understudied or previous studies reported inconsistent findings. This study investigated the association of self-harm with overcrowding and turnover in the largest pre-trial Swiss prison in Geneva. Data were collected yearly between 2011 and 2017. Measures included self-harm (all kinds of self-injuring acts requiring medical attention, including self-strangulations and self-hangings). We performed meta-regressions to analyse the relationships between self-harm and institutional factors. Self-harm events were frequent, with a prevalence estimate of 26.4%. Overcrowding and turnover were high (average occupation rate of 177% and average turnover of 73%, respectively). Overcrowding and turnover were significantly associated with self-harm (respectively b = 0.068, p < 0.001 and (b = 1.257, p < 0.001). In both cases, self-harm was higher when overcrowding and turnover increased. Overcrowding and turnover raise important human rights concerns and have damaging effects on the health of people living in detention. Identification of and care for this vulnerable population at risk of self-harm are needed and institutional factors should be addressed.
Gut Microbiota and Type 1 Diabetes
Authors: Han Hui , Li Yuying , Fang Jun , Liu Gang , Yin Jie , Li Tiejun , Yin Yulong
Published: March 2018

Recently, the onset of type 1 diabetes (T1D) has increased rapidly and became a major public health concern worldwide. Various factors are associated with the development of T1D, such as diet, genome, and intestinal microbiota. The gastrointestinal (GI) tract harbors a complex and dynamic population of microorganisms, the gut microbiota, which exert a marked influence on the host homeostasis and metabolic diseases. Recent evidence shows that altered gut bacterial composition (dysbiosis) is highly associated with the pathogenesis of insulin dysfunction and T1D and, thus, targeting gut microbiota may serve as a therapeutic potential for T1D patients. In this study, we updated the effect of gut microbiota on T1D and potential mechanisms were discussed.
The Different Facets of Extracellular Calcium Sensors: Old and New Concepts in Calcium-Sensing Receptor Signalling and Pharmacology
Authors: Gerbino Andrea , Colella Matilde
Published: March 2018

The current interest of the scientific community for research in the field of calcium sensing in general and on the calcium-sensing Receptor (CaR) in particular is demonstrated by the still increasing number of papers published on this topic. The extracellular calcium-sensing receptor is the best-known G-protein-coupled receptor (GPCR) able to sense external Ca2+ changes. Widely recognized as a fundamental player in systemic Ca2+ homeostasis, the CaR is ubiquitously expressed in the human body where it activates multiple signalling pathways. In this review, old and new notions regarding the mechanisms by which extracellular Ca2+ microdomains are created and the tools available to measure them are analyzed. After a survey of the main signalling pathways triggered by the CaR, a special attention is reserved for the emerging concepts regarding CaR function in the heart, CaR trafficking and pharmacology. Finally, an overview on other Ca2+ sensors is provided.
β4 and β6 Integrin Expression Is Associated with the Subclassification and Clinicopathological Features of Intrahepatic Cholangiocarcinoma
Authors: Soejima Yurie , Takeuchi Miho , Akashi Takumi , Sawabe Motoji , Fukusato Toshio
Published: March 2018

Intrahepatic cholangiocarcinoma (ICC) is a heterogeneous group of cancers of the intrahepatic biliary tract. However, few studies have evaluated integrin expression according to an ICC subgroup. We immunohistochemically investigated α6β4 (β4) and αvβ6 (β6) integrin expressions in 48 ICCs, and evaluated their relationship with clinical and pathological parameters and ligand expression, as well as transforming growth factor (TGF)-β1. β4 and β6 expressions were detected in 46 (96%) and 35 (73%) ICC cases, respectively. We classified ICC into negative, low (β4, 29 cases; β6, 36 cases), or high (β4, 19 cases; β6, 12 cases) integrin expression groups. β4 and β6 integrin levels were higher in the non-peripheral central localization type ICC than in the peripheral localization type; they were also higher in the periductal-infiltrating or intraductal-growth types than in the mass-forming type ICC; lastly, they were higher in the well-differentiated type than in the poorly-differentiated type ICC. High expression was related to bile duct invasion. In addition, β4 and β6 expressions were associated with mucin production and the expression of cytoplasmic epithelial membrane antigen, laminin-5, and tenascin-C. TGF-β1 was correlated with β6 expression and poor overall survival. These results suggest that integrin expression is associated with subclassification and clinicopathological features of ICC through the coincident expression of their ligands and TGF-β1.
Neutron Imaging at Compact Accelerator-Driven Neutron Sources in Japan
Authors: Kiyanagi Yoshiaki
Published: March 2018

Neutron imaging has been recognized to be very useful to investigate inside of materials and products that cannot be seen by X-ray. New imaging methods using the pulsed structure of neutron sources based on accelerators has been developed also at compact accelerator-driven neutron sources and opened new application fields in neutron imaging. The world’s first dedicated imaging instrument at pulsed neutron sources was constructed at J-PARC in Japan owing to the development of such new methods. Then, usefulness of the compact accelerator-driven neutron sources in neutron science was recognized and such facilities were newly constructed in Japan. Now, existing and new sources have been used for neutron imaging. Traditional imaging and newly developed pulsed neutron imaging such as Bragg edge transmission have been applied to various fields by using compact and large neutron facilities. Here, compact accelerator-driven neutron sources used for imaging in Japan are introduced and some of their activities are presented.
Geometrically Nonlinear Field Fracture Mechanics and Crack Nucleation, Application to Strain Localization Fields in Al-Cu-Li Aerospace Alloys
Authors: Gupta Satyapriya , Taupin Vincent , Fressengeas Claude , Jrad Mohamad
Published: March 2018

The displacement discontinuity arising between crack surfaces is assigned to smooth densities of crystal defects referred to as disconnections, through the incompatibility of the distortion tensor. In a dual way, the disconnections are defined as line defects terminating surfaces where the displacement encounters a discontinuity. A conservation statement for the crack opening displacement provides a framework for disconnection dynamics in the form of transport laws. A similar methodology applied to the discontinuity of the plastic displacement due to dislocations results in the concurrent involvement of dislocation densities in the analysis. Non-linearity of the geometrical setting is assumed for defining the elastic distortion incompatibility in the presence of both dislocations and disconnections, as well as for their transport. Crack nucleation in the presence of thermally-activated fluctuations of the atomic order is shown to derive from this nonlinearity in elastic brittle materials, without any algorithmic rule or ad hoc material parameter. Digital image correlation techniques applied to the analysis of tensile tests on ductile Al-Cu-Li samples further demonstrate the ability of the disconnection density concept to capture crack nucleation and relate strain localization bands to consistent disconnection fields and to the eventual occurrence of complex and combined crack modes in these alloys.
Indentation Behavior and Mechanical Properties of Tungsten/Chromium co-Doped Bismuth Titanate Ceramics Sintered at Different Temperatures
Authors: Xie Shaoxiong , Xu Jiageng , Chen Yu , Tan Zhi , Nie Rui , Wang Qingyuan , Zhu Jianguo
Published: March 2018

A sort of tungsten/chromium(W/Cr) co-doped bismuth titanate (BIT) ceramics (Bi4Ti2.95W0.05O12.05 + 0.2 wt % Cr2O3, abbreviate to BTWC) are ordinarily sintered between 1050 and 1150 °C, and the indentation behavior and mechanical properties of ceramics sintered at different temperatures have been investigated by both nanoindentation and microindentation technology. Firstly, more or less Bi2Ti2O7 grains as the second phase were found in BTWC ceramics, and the grain size of ceramics increased with increase of sintering temperatures. A nanoindentation test for BTWC ceramics reveals that the testing hardness of ceramics decreased with increase of sintering temperatures, which could be explained by the Hall–Petch equation, and the true hardness could be calculated according to the pressure-state-response (PSR) model considering the indentation size effect, where the value of hardness depends on the magnitude of load. While, under the application of microsized Vickers, the sample sintered at a lower temperature (1050 °C) gained four linearly propagating cracks, however, they were observed to shorten in the sample sintered at a higher temperature (1125 °C). Moreover, both the crack deflection and the crack branching existed in the latter. The hardness and the fracture toughness of BTWC ceramics presented a contrary variational tendency with increase of sintering temperatures. A high sintering tends to get a lower hardness and a higher fracture toughness, which could be attributed to the easier plastic deformation and the stronger crack inhibition of coarse grains, respectively, as well as the toughening effect coming from the second phase.
A Numerical Method for Solving a Class of Nonlinear Second Order Fractional Volterra Integro-Differntial Type of Singularly Perturbed Problems
Authors: Syam Muhammed , Abu Omar Mohammed
Published: March 2018

In this paper, we study a class of fractional nonlinear second order Volterra integro-differential type of singularly perturbed problems with fractional order. We divide the problem into two subproblems. The first subproblems is the reduced problem when ϵ = 0 . The second subproblems is fractional Volterra integro-differential problem. We use the finite difference method to solve the first problem and the reproducing kernel method to solve the second problem. In addition, we use the pade’ approximation. The results show that the proposed analytical method can achieve excellent results in predicting the solutions of such problems. Theoretical results are presented. Numerical results are presented to show the efficiency of the proposed method.
A Control and Detecting System of Micro-Near-Infrared Spectrometer Based on a MOEMS Scanning Grating Mirror
Authors: Liu Haitao , Wen Zhiyu , Li Dongling , Huang Jian , Zhou Ying , Guo Pengfei
Published: March 2018

Based on the scanning grating mirror we developed, this paper presents a method of the precise control of a scanning grating mirror and of high-speed spectrum data detection. In addition, the system circuit of the scanning grating mirror control and spectrum signal detecting is designed and manufactured in this paper. The mirror control system includes a drive generator module, an amplitude detection module, a feedback control module, and a variable gain amplification (VGA) module; the detecting system includes a field programmable gate array (FPGA) main control module, a synchronous trigger module, an analog-digital conversion (ADC) module, and a universal serial bus (USB) interface module. The final results of the experiment show that the control system has successfully realized the precision control of the swing of the scanning grating mirror and that the detecting system has successfully realized the high-speed acquisition and transmission of the spectral signal and the angle signals. The spectrum has been reconstructed according to the mathematical relationship between the wavelength λ and the angle β of the mirror. The resolution of the spectrometer reaches 10 nm in the wavelength range of 800–1800 nm, the signal-to-noise ratio (SNR) of the spectrometer is 4562 at full scale, the spectrum data drift is 0.9% in 24 h, and the precision of the closed loop control is 0.06%.
On Your Own: Older Adults’ Food Choice and Dietary Habits
Authors: Whitelock Emily , Ensaff Hannah
Published: March 2018

The United Kingdom, in common with many countries, has an ageing demographic. Changes accompanying ageing can influence food choice and dietary habits. This study explored older adults’ perceptions and practices related to dietary behaviour and the factors influencing their food choice in later life. Semi-structured focus-group discussions were conducted with 30 individuals (aged 63–90 years) in a UK city. An inductive thematic approach was adopted for data analysis, and 4 themes and 12 sub-themes emerged: age-related changes (lower appetite, food changes, declining physical function); food access (food cost, support with food, maintaining independence); on your own (cooking for one, eating alone, shopping for one); and relationship with food (food variety, eating what you want, dieting). These influenced participants’ food acquisition, food preparation and cooking, as well as eating habits. Living alone and its substantial influence, as well as associated social isolation and loneliness, were highlighted in many of the discussions. Given the possible implications for nutritional intake, further work is recommended in this area. Likewise, steps should be taken to improve food access, increase opportunities for commensal eating and, fundamentally, address social isolation and loneliness in the older population.
Geometric Accuracy of Sentinel-1A and 1B Derived from SAR Raw Data with GPS Surveyed Corner Reflector Positions
Authors: Schmidt Kersten , Reimann Jens , Tous Ramon Núria , Schwerdt Marco
Published: March 2018

The geometric accuracy of synthetic aperture radar (SAR) data is usually derived from level-1 products using accurately surveyed corner reflector positions. This paper introduces a novel approach that derives the range delay and azimuth shift from acquired SAR raw data (level-0 products). Therefore, the propagation path is completely retrieved from SAR pulse transmission up to the reception of the point target’s backscatter. The procedure includes simple pulse compression in range and azimuth instead of full SAR data processing. By applying this method, the geometric accuracy of ESA’s Sentinel-1 SAR satellites (Sentinel-1A and Sentinel-1B) is derived for each satellite overpass by using corner reflectors with precisely surveyed GPS positions. The results show that the azimuth bias of about 2 m found in level-1 products for Stripmap acquisitions is reduced to about 15 cm. This indicates an artificial bias arising from operational Sentinel-1 SAR data processing. The remaining range bias of about 1.0 m, observed in L0-products, is interpreted as the offset between the SAR antenna phase center and the spacecraft’s center of gravity. The relative pixel localization accuracy derived with the proposed method is about 12 cm for the evaluated acquisitions. Compared to the full processed level-1 SAR data products, this accuracy is similar in the range direction, but, for the azimuth direction, it is improved by about 50% with the proposed method.
Temperature and Vibration Dependence of the Faraday Effect of Gd2O3 NPs-Doped Alumino-Silicate Glass Optical Fiber
Authors: Ju Seongmin , Kim Jihun , Linganna Kadathala , Watekar Pramod , Kang Seong , Kim Bok , Boo Seongjae , Lee Youjin , An Yong , Kim Cheol , Han Won-Taek
Published: March 2018

All-optical fiber magnetic field sensor based on the Gd2O3 nano-particles (NPs)-doped alumino-silicate glass optical fiber was developed, and its temperature and vibration dependence on the Faraday Effect were investigated. Uniformly embedded Gd2O3 NPs were identified to form in the core of the fiber, and the measured absorption peaks of the fiber appearing at 377 nm, 443 nm, and 551 nm were attributed to the Gd2O3 NPs incorporated in the fiber core. The Faraday rotation angle (FRA) of the linearly polarized light was measured at 650 nm with the induced magnetic field by the solenoid. The Faraday rotation angle was found to increase linearly with the magnetic field, and it was about 18.16° ± 0.048° at 0.142 Tesla (T) at temperatures of 25 °C–120 °C, by which the estimated Verdet constant was 3.19 rad/(T∙m) ± 0.01 rad/(T∙m). The variation of the FRA with time at 0.142 T and 120 °C was negligibly small (−9.78 × 10−4 °/min). The variation of the FRA under the mechanical vibration with the acceleration below 10 g and the frequency above 50 Hz was within 0.5°.
A Robust Real Time Direction-of-Arrival Estimation Method for Sequential Movement Events of Vehicles
Authors: Liu Huawei , Li Baoqing , Yuan Xiaobing , Zhou Qianwei , Huang Jingchang
Published: March 2018

Parameters estimation of sequential movement events of vehicles is facing the challenges of noise interferences and the demands of portable implementation. In this paper, we propose a robust direction-of-arrival (DOA) estimation method for the sequential movement events of vehicles based on a small Micro-Electro-Mechanical System (MEMS) microphone array system. Inspired by the incoherent signal-subspace method (ISM), the method that is proposed in this work employs multiple sub-bands, which are selected from the wideband signals with high magnitude-squared coherence to track moving vehicles in the presence of wind noise. The field test results demonstrate that the proposed method has a better performance in emulating the DOA of a moving vehicle even in the case of severe wind interference than the narrowband multiple signal classification (MUSIC) method, the sub-band DOA estimation method, and the classical two-sided correlation transformation (TCT) method.
Infrared Hollow Optical Fiber Probe for Localized Carbon Dioxide Measurement in Respiratory Tracts
Authors: Katagiri Takashi , Shibayama Kyosuke , Iida Takeru , Matsuura Yuji
Published: March 2018

A real-time gas monitoring system based on optical absorption spectroscopy is proposed for localized carbon dioxide (CO2) measurement in respiratory tracts. In this system, a small gas cell is attached to the end of a hollow optical fiber that delivers mid-infrared light with small transmission loss. The diameters of the fiber and the gas cell are smaller than 1.2 mm so that the probe can be inserted into a working channel of common bronchoscopes. The dimensions of the gas cell are designed based on absorption spectra of CO2 standard gases in the 4.2 μm wavelength region, which are measured using a Fourier-transform infrared spectrometer. A miniature gas cell that is comprised of a stainless-steel tube with slots for gas inlet and a micro-mirror is fabricated. A compact probing system with a quantum cascade laser (QCL) light source is built using a gas cell with a hollow optical fiber for monitoring CO2 concentration. Experimental results using human breaths show the feasibility of the system for in-situ measurement of localized CO2 concentration in human airways.
Computationally Efficient Automatic Coast Mode Target Tracking Based on Occlusion Awareness in Infrared Images
Authors: Kim Sohyun , Jang Gwang-Il , Kim Sungho , Kim Junmo
Published: March 2018

This paper proposes the automatic coast mode tracking of centroid trackers for infrared images to overcome the target occlusion status. The centroid tracking method, using only the brightness information of an image, is still widely used in infrared imaging tracking systems because it is difficult to extract meaningful features from infrared images. However, centroid trackers are likely to lose the track because they are highly vulnerable to screened status by the clutter or background. Coast mode, one of the tracking modes, maintains the servo slew rate with the tracking rate right before the loss of track. The proposed automatic coast mode tracking method makes decisions regarding entering coast mode by the prediction of target occlusion and tries to re-lock the target and resume the tracking after blind time. This algorithm comprises three steps. The first step is the prediction process of the occlusion by checking both matters which have target-likelihood brightness and which may screen the target despite different brightness. The second step is the process making inertial tracking commands to the servo. The last step is the process of re-locking a target based on the target modeling of histogram ratio. The effectiveness of the proposed algorithm is addressed by presenting experimental results based on computer simulation with various test imagery sequences compared to published tracking algorithms. The proposed algorithm is tested under a real environment with a naval electro-optical tracking system (EOTS) and airborne EO/IR system.
Feasibility of Using Elastic Wave Velocity Monitoring for Early Warning of Rainfall-Induced Slope Failure
Authors: Chen Yulong , Irfan Muhammad , Uchimura Taro , Zhang Ke
Published: March 2018

Rainfall-induced landslides are one of the most widespread slope instability phenomena posing a serious risk to public safety worldwide so that their temporal prediction is of great interest to establish effective warning systems. The objective of this study is to determine the effectiveness of elastic wave velocities in the surface layer of the slope in monitoring, prediction and early warning of landslide. The small-scale fixed and varied, and large-scale slope model tests were conducted. Analysis of the results has established that the elastic wave velocity continuously decreases in response of moisture content and deformation and there was a distinct surge in the decrease rate of wave velocity when failure was initiated. Based on the preliminary results of this analysis, the method using the change in elastic wave velocity proves superior for landslide early warning and suggests that a warning be issued at switch of wave velocity decrease rate.
Optimizing Propagation of Staphylococcus aureus Infecting Bacteriophage vB_SauM-phiIPLA-RODI on Staphylococcus xylosus Using Response Surface Methodology
Authors: González-Menéndez Eva , Arroyo-López Francisco Noé , Martínez Beatriz , García Pilar , Garrido-Fernández Antonio , Rodríguez Ana
Published: March 2018

The use of bacteriophages for killing pathogenic bacteria is a feasible alternative to antibiotics and disinfectants. To obtain the large quantities of phages required for this application, large-scale production of bacteriophages must be optimized. This study aims to define conditions that maximize the phage yield of the virulent and polyvalent staphylococcal bacteriophage vB_SauM-phiIPLA-RODI in broth culture, using the food-grade species Staphylococcus xylosus as the host strain to reduce the risk of growing massive quantities of pathogenic bacteria and therefore, to ensure the safety of the final phage stock. The effect of four variables, namely initial bacterial concentration (5.66–8.40 log10 colony-forming unit (CFU)/mL), initial phage concentration (5–8 log10 plaque-forming unit (PFU)/mL), temperature (21–40 °C) and agitation (20–250 rpm), on phage yield (response) was studied by using response surface methodology (RSM). Successive experimental designs showed that agitation did not significantly impact phage yield, while temperature did have a significant effect, with 38 °C being the optimum for phage propagation. The results allowed the design of a model to describe phage yield as a function of the initial bacterial and phage concentrations at fixed agitation (135 rpm), and optimum temperature (38 °C). The maximum experimental phage yield obtained was 9.3 log10 PFU/mL, while that predicted by the model under the optimized conditions (7.07 log10 CFU/mL initial bacterial population and 6.00 log10 PFU/mL initial phage titer) was 9.25 ± 0.30 log10 PFU/mL, with the desirability of 0.96. This yield is comparable to that obtained when the phage was propagated on the original host, Staphylococcus aureus. Bacteriophage phiIPLA-RODI showed the same host range and very similar biofilm removal ability regardless of the staphylococcal species used for its propagation. The results presented in this study show the suitability of using a food-grade strain of S. xylosus for the propagation of S. aureus infecting phages and the application of RSM to define the optimal propagation conditions.
Identification of a Contaminant Source Location in a River System Using Random Forest Models
Authors: Lee Yoo , Park Chuljin , Lee Mi
Published: March 2018

We consider the problem of identifying the source location of a contaminant via analyzing changes in concentration levels observed by a sensor network in a river system. To address this problem, we propose a framework including two main steps: (i) pre-processing data; and (ii) training and testing a classification model. Specifically, we first obtain a data set presenting concentration levels of a contaminant from a simulation model, and extract numerical characteristics from the data set. Then, random forest models are generated and assessed to identify the source location of a contaminant. By using the numerical characteristics from the prior step as their inputs, the models provide outputs representing the possibility, i.e., a value between 0 and 1, of a spill event at each candidate location. The performance of the framework is tested on a part of the Altamaha river system in the state of Georgia, United States of America.
DYNAMIC IMPACT OF HEAVY LONG VEHICLES WITH EQUALLY SPACED AXLES ON SHORT-SPAN HIGHWAY BRIDGES
Authors: MOHAMMED Omar , GONZÁLEZ Arturo , CANTERO Daniel
Published: March 2018

Extremely large trucks with a weight exceeding the standard require a permit before they are allowed to cross the bridges of a specific route. For the purpose of safety, an escort is often employed to maintain a distance between vehicles and to ensure that the bridge load remain below the allowed maximum. Given that the speed of these large vehicles is quite slow and that the amplitude of vibrations normally declines when the vehicle mass is large, a minor dynamic amplification of the bridge response is expected. However, some of these large trucks have a unique feature characterized by “multiple equally-spaced axles”, something that is uncommon in normal vehicle. The application of axle forces at equal intervals can dynamically excite bridges to a considerable extent, even at low speeds. These “critical” low speeds are estimated a priori from the axle spacing of the truck and the main frequency of vibration of the bridge. This paper demonstrates that when the “critical” speed is unavoidable, a relatively high dynamic allowance must be added to static calculations before granting a permit to a long heavy vehicle.
HEAVY VEHICLE MULTI-BODY DYNAMIC SIMULATIONS TO ESTIMATE SKIDDING DISTANCE
Authors: ZAMZAMZADEH Mahdieh , SAIFIZUL Ahmad Abdullah , RAMLI Rahizar , SOONG Ming Foong
Published: March 2018

The skid mark is valuable for accident reconstruction as it provides information about the drivers’ braking behaviour and the speed of heavy vehicles. However, despite its importance, there is currently no mathematical model available to estimate skidding distance (SD) as a function of vehicle characteristics and road conditions. This paper attempts to develop a non-linear regression model that is capable of reliably predicting the skidding distance of heavy vehicles under various road conditions and vehicle characteristics. To develop the regression model, huge data sets were derived from complex heavy vehicle multi-body dynamic simulation. An emergency braking simulation was conducted to examine the skidding distance of a heavy vehicle model subject to various Gross Vehicle Weight (GVW) and vehicle speeds, as well as the coefficient of friction of the road under wet and dry conditions. The results suggested that the skidding distance is significantly affected by Gross Vehicle Weight, speeds, and coefficient of friction of the road. The improved non-linear regression model provides a better prediction of the skidding distance than that of the conventional approach thus suitable to be employed as an alternative model for skidding distance of heavy vehicles in accident reconstruction.
FIELD TESTING AND DYNAMIC ANALYSIS OF OLD CONTINUOUS TRUSS STEEL BRIDGE
Authors: KILIKEVIČIUS Artūras , BAČINSKAS Darius , JUREVIČIUS Mindaugas , KILIKEVIČIENĖ Kristina , FURSENKO Antanas , JAKAITIS Jonas , TOLOČKA Eligijus
Published: March 2018

Paper presents dynamic field test and analysis results of a three span railway steel continuous truss bridge over river Neris in Jonava. Bridge was originally constructed in 1914. In the period of the World War II and afterwards the bridge was many time destroyed by German and Soviet armies. In 1948 the new railway bridge was constructed. Object of the present paper is to evaluate dynamic behaviour of the railway bridge after 67 years in service. Experimental dynamic analysis was divided into resonance-vibration, forced-vibration and free vibration studies. Resonance-vibrations of the bridge were excited by separate actions of shock loading and standard locomotive 2M62. Forced-vibrations were measured under the action of locomotive 2M62. Additionally, free vibration tests under passage of freight and passenger trains have been carried out. Structural dynamic response of the bridge was analysed using Brüel & Kjær LAN XI dynamic test system and software. As a result, main dynamic parameters of the bridge were obtained. The main results include: mode shapes, frequencies of natural and forced vibrations, damping ratios, maximum amplitudes of accelerations, dynamic displacements. The obtained values were compared to the requirements of different design codes. Based on the achieved results concluding remarks and recommendations regarding the condition of the bridge after long-term period in service were presented.
MODAL TESTING OF AN ISOLATED OVERPASS BRIDGE IN ITS CONSTRUCTION STAGES
Authors: ARAS Fuat
Published: March 2018

This study presents the application of ambient vibration survey based dynamic testing on an isolated, precast and pre-stressed overpass bridge during and after its construction. In the studied three-bay bridge, the girders are located on the elastomeric bearings carried by two abutments and two internal piers. The first modal testing is performed after the placement of the girders on the elastomeric bearings and dynamic properties of the uncompleted bridge are determined. After the completion of all construction works and the opening of the overpass to human traffic, the modal testing is repeated to obtain the dynamic properties of the final structure. The dynamic properties obtained in both analyses are used to interpret the effects of the performed works between two modal testing. Moreover, the structural behaviour of isolated, precast and pre-stressed bridges is evaluated in detail.
The Cosmic Web around the Brightest Galaxies during the Epoch of Reionization
Authors: Ren Keven , Trenti Michele , Mutch Simon J.
Published: March 2018

The most luminous galaxies at high redshift are generally considered to be hosted in massive dark-matter halos of comparable number density, hence residing at the center of over-densities/protoclusters. We assess the validity of this assumption by investigating the clustering around the brightest galaxies populating the cosmic web at redshift z ∼ 8–9 through a combination of semi-analytic modeling and Monte Carlo simulations of mock Hubble Space Telescope WFC3 observations. The innovative aspect of our approach is the inclusion of a log-normal scatter parameter Σ in the galaxy luminosity versus halo mass relation, extending the conditional luminosity function framework extensively used at low redshift to high z. Our analysis shows that the larger the value of Σ, the less likely it is that the brightest source in a given volume is hosted in the most massive halo, and hence the weaker the overdensity of neighbors. We derive a minimum value of Σ as a function of redshift by considering stochasticity in the halo assembly times, which affects galaxy ages and star formation rates in our modeling. We show that Σmin(z) ∼ 0.15–0.3, with Σmin increasing with redshift as a consequence of shorter halo assembly periods at higher redshifts. Current observations (m

AB
∼ 27) of the environment of spectroscopically confirmed bright sources at z > 7.5 do not show strong evidence of clustering and are consistent with our modeling predictions for Σ ≥ Σmin. Deeper future observations reaching m

AB
 ∼ 28.2–29 would have the opportunity to clearly quantify the clustering strength and hence to constrain Σ, investigating the physical processes that drive star formation in the early universe.
Optical and Gamma-Ray Variability Behaviors of 3C 454.3 from 2006 to 2011
Authors: Fan Xu-Liang , Li Shao-Kun , Liao Neng-Hui , Chen Liang , Liu Hong-Tao , Lu Kai-Xing , Yan Da-Hai , Zhang Rui-Yu , Guo Qian , Wu Qingwen , Bai Jin-Ming
Published: March 2018

We present our photometric monitoring of a flat spectrum radio quasar 3C 454.3 at Yunnan observatories from 2006 to 2011. We find that the optical color of 3C 454.3 shows an obvious redder-when-brighter trend, which reaches a saturation stage when the source is brighter than 15.15 mag at V band. We perform a simulation with multiple values of disk luminosity and spectral index to reproduce the magnitude–color diagram. The results show that the contamination caused by the disk radiation alone is difficult to produce the observed color variability. The variability properties during the outburst in 2009 December are also compared with γ-ray data derived from the Fermi γ-ray space telescope. The flux variation of these two bands follows a linear relation with

, which provides observational evidence for the external Compton process in 3C 454.3. Meanwhile, this flux correlation indicates that electron injection is the main mechanism for the variability origin. We also explore the variation of the flux ratio F

γ
/F

R
and the detailed structures in the light curves, and discuss some possible origins for the detailed variability behaviors.
Successive X-class Flares and Coronal Mass Ejections Driven by Shearing Motion and Sunspot Rotation in Active Region NOAA 12673
Authors: Yan X. L. , Wang J. C. , Pan G. M. , Kong D. F. , Xue Z. K. , Yang L. H. , Li Q. L. , Feng X. S.
Published: March 2018

We present a clear case study on the occurrence of two successive X-class flares, including a decade-class flare (X9.3) and two coronal mass ejections (CMEs) triggered by shearing motion and sunspot rotation in active region NOAA 12673 on 2017 September 6. A shearing motion between the main sunspots with opposite polarities began on September 5 and lasted even after the second X-class flare on September 6. Moreover, the main sunspot with negative polarity rotated around its umbral center, and another main sunspot with positive polarity also exhibited a slow rotation. The sunspot with negative polarity at the northwest of the active region also began to rotate counterclockwise before the onset of the first X-class flare, which is related to the formation of the second S-shaped structure. The successive formation and eruption of two S-shaped structures were closely related to the counterclockwise rotation of the three sunspots. The existence of a flux rope is found prior to the onset of two flares by using nonlinear force-free field extrapolation based on the vector magnetograms observed by Solar Dynamics Observatory/Helioseismic and Magnetic Image. The first flux rope corresponds to the first S-shaped structures mentioned above. The second S-shaped structure was formed after the eruption of the first flux rope. These results suggest that a shearing motion and sunspot rotation play an important role in the buildup of the free energy and the formation of flux ropes in the corona that produces solar flares and CMEs.
On mechanism of antiarrhythmic action of some dimethylphenylacetamide derivatives
Authors: Hameed Salem Yahya Mohamed , Kurganov Nikolay A. , Blinova Ekaterina V. , Semeleva Elena V. , Lebedev Arkadiy B. , Blinov Dmirty S. , Novikov Andrei V.
Published: March 2018

Abbreviations: AC – acetylcholyne; AF – atrial fibrillation; AP – action potential; BLM – bi-lipid membrane; DPA -Dimethylphenylacetamide; VA – ventricular arrhythmia

Introduction: The study aim was to identify essential elements of the antiarrhythmic action mechanism of tertiary and quaternary derivatives of Dimethylphenylacetamide.

Materials and Methods: The study was conducted in albino rats and mice of both sexes; isolated neurons of mollusc Limneastagnalis; and strips of rats’ right ventricle myocardium. Two compounds of Dimethylphenylacetamide LKhT-3-00 and LKhT-12-02 were studied. The cholynolytic property of the compounds was investigated by using a Schallek method in the authors’ modification. The adrenotropic activity of the derivatives was explored by Moore and Spear (1984), as well a by the method of catecholamine level detection in heart tissue. The permeability of derivatives through BLM was evaluated experimentally and theoretically. The derivatives’ influence on Na+-current was studied directly and indirectly.

Results and Discussion: Neither tertiary nor quaternary derivatives possess the cholynolytic property. LKhT-3-00 prevented an increase in the adrenaline concentration in the left ventricle myocardium. The compounds prevent catecholamine arrhythmia and conductivity disorders. LKhT-3-00 like Lidocaine passes through the BLM of the cardiac cell in an ionised form, whereas the quaternary derivative permeates cardiac cell membrane in an electro-neutral form. Lidocaine derivatives restrain acute ischemia-induced oxidative process growth in the cardiac muscle. Simultaneously, the LKhT-3-00 compound can activate antioxidant mechanisms and prevent acidosis and optimise the balance between [O2] and [CO2] concentrations in coronary dark blood. At a concentration of 10 mg/ml, although the derivatives reduce the amplitude of the leading edge of AP and its rate of increase, they do not, however, affect the duration of AP.

Conclusions: The compounds possess the Na+-blocking and cell-protecting properties. They do not affect K+-current through Kv4.3-channels.
L’encastrement des activités économiques dans les associations religieuses. Une illustration de la région de Butembo (Nord-Kivu, R.D. Congo)
Authors: Musongora Syasaka Emmanuel
Published: March 2018

Depuis son indépendance politique, plus particulièrement la décennie 1990, la République Démocratique du Congo fait face à une émergence des associations de tout genre. Suite à une crise multiforme (politique, économique, sociale, …), leur rôle est devenu primordial. L’un des plus importants acteurs associatifs est la composante religieuse. Leur effervescence s’accompagne des activités socio-économiques qui font de ceux-ci des acteurs incontournables. Ceci revient à dire que les activités économiques et religieuses sont parfois imbriquées les unes les autres.
Acteur populaire, économie populaire et développement réel : contribution à la théorie critique du changement social aux Suds
Authors: Amougou Thierry
Published: March 2018

Forme de changement social, le développement a, dans sa version dominante, le marché autorégulateur, l’ homo œconomicus , la croissance économique et la rationalité formelle au centre de sa dynamique. Celle-ci vise le passage des Suds des sociétés traditionnelles aux sociétés modernes en suivant le chemin des pays du Nord. Très souvent, le développement réel n’est pas réalisé. L’acteur populaire dont les pratiques économiques et sociales sont légitimes, substantielles et allient traditionnel et moderne, semble capable de (ré) enchanter le développement en mobilisant ses dimensions réelles.
La « voie paysanne » et ses critiques : de la question agraire classique à une alternative politique contemporaine
Authors: Verhaegen Étienne
Published: March 2018

Avec la montée des mouvements dits « paysans », les débats sur la place de la petite agriculture familiale dans la capitalisation de l’agriculture retrouvent de la vigueur. Les paysans constituent-ils une force politique capable de contrer les dynamiques du corporate food regime , comme le soutiennent les défenseurs de la « voie paysanne » ? Ou sont-ils appelés à disparaître, emportés par une inévitable internalisation des relations capitalistes de production et par le renforcement des luttes de classes qui en résultent ? Cette contribution soutient que certaines critiques de la voie paysanne construisent une essentialisation de la figure du petit producteur marchand qui vise, par ses angles morts, à renforcer les dynamiques du capitalisme néolibéral.
Vulnérabilisation ou résilience des banlieues insalubres de Dakar
Authors: Cissé Birane , Quensière Jacques , Kane Alioune
Published: March 2018

Dans la banlieue de Dakar où l’urbanisation de certains quartiers s’est faite dans l’urgence lors de la vague d’exode rurale des années de sécheresse, la remise en eau des bas-fonds crée des conditions d’insalubrité qui conduisent à s’interroger sur l’usage actuellement fait de la notion de résilience. Est-il réellement du devoir (du pouvoir) des populations de s’adapter aux conditions d’insalubrité dans lesquelles l’État les a plongées et maintenues depuis cinquante ans ? Des réponses sont proposées ici.
La Chine, principale bénéficiaire du mécanisme pour un développement propre (MDP)
Authors: Lacour Pauline
Published: March 2018

La Chine a su profiter pleinement du mécanisme pour un développement propre (MDP) du Protocole de Kyoto, exploitant ses ressources financières et technologiques additionnelles. Le cadre institutionnel encadrant les MDP a favorisé leur adéquation avec la stratégie énergétique domestique. L’étude empirique précise que le mécanisme est un canal de diffusion de technologies vertes, près d’un tiers des projets financés par des firmes japonaises en Chine (2005-2011) conduisant à la diffusion d’équipements respectueux de l’environnement et/ou à la mise en œuvre de plans de formation.
Impact de la diffusion d’un guide sur la nutrition et l’activité physique aux élèves de 5 e de France métropolitaine
Authors: Mathiot Hélène , Nugier Angélique , Nguyen-Thanh Viêt
Published: March 2018

Introduction : « J’aime manger, j’aime bouger, le guide nutrition pour les adolescents », l’un des huit guides d’information du Programme National Nutrition Santé (PNNS), fait l’objet d’un plan de diffusion annuel par Santé publique France aux élèves des classes de 5 e par l’intermédiaire des professeurs de Sciences de la Vie et de la Terre (SVT). Notre étude avait pour objectif d’évaluer l’impact de ce plan de diffusion et la perception du guide auprès des élèves de 5 e et des professeurs de SVT. La connaissance des repères nutritionnels par les adolescents a également été évaluée. Méthode : L’étude, reposant sur une méthode mixte, a été réalisée en 2015 auprès de 432 adolescents scolarisés en 5 e , interrogés en face-à-face à leur domicile ; et de 20 professeurs de SVT de classes de 5 e , interrogés lors d’entretiens individuels ou de focus groups . Résultats : Le guide a obtenu un score de reconnaissance de 40 % auprès des jeunes, qui l’ont majoritairement vu au collège pendant un cours. 30 % des jeunes ont déclaré avoir lu ou survolé le guide et plus des trois quart, que le guide leur plaisait. Les adolescents et les professeurs trouvaient le guide clair et accessible, en appréciaient globalement le contenu, mais considéraient qu’il mériterait d’être modernisé. Conclusion : La diffusion systématique du guide, ciblée sur un niveau de classe en milieu scolaire est une stratégie efficace qui permet de toucher un maximum de jeunes ; elle doit donc être poursuivie dans le futur. Une modernisation du guide et un meilleur accompagnement des professeurs dans sa diffusion pourraient permettre d’augmenter encore la performance de cette diffusion.
Interventions pour l’arrêt du tabac chez les fumeurs de faible niveau socio-économique : synthèse de la littérature
Authors: Guignard Romain , Nguyen-Thanh Viêt , Delmer Olivier , Lenormand Marie-Camille , Blanchoz Jean-Marie , Arwidson Pierre
Published: March 2018

Introduction : Dans la plupart des pays occidentaux, la consommation de tabac apparaît très différenciée selon le niveau socio-économique. Deux revues systématiques publiées en 2014 montrent que la plupart des interventions recommandées pour l’arrêt du tabac, notamment individuelles, ont tendance à accroître les inégalités sociales de santé. Afin de mettre à disposition des décideurs et des acteurs de terrain un ensemble de données probantes concernant les modalités d’interventions pour inciter et aider les fumeurs socio-économiquement défavorisés à arrêter de fumer, une analyse de la littérature la plus récente a été réalisée. Méthodes : La recherche documentaire concerne les articles publiés entre le 1 er  janvier 2013 et avril 2016. Seules les études réalisées dans des pays européens ou au stade 4 de l’épidémie tabagique (États-Unis, Canada, Australie, Nouvelle-Zélande) ont été incluses. Les articles retenus ont fait l’objet d’une double-sélection. Résultats : Vingt-trois études ont été identifiées, concernant notamment les campagnes médiatiques, le soutien comportemental en face-à-face, l’aide à distance ou la sensibilisation au tabagisme passif des enfants. Certaines interventions adaptées aux publics précaires ont fait la preuve de leur efficacité. Conclusions : Certaines caractéristiques permettraient d’atteindre les publics défavorisés et de les accompagner davantage, dont une offre de proximité, une démarche proactive et la co-construction avec les publics cibles.