bluuebunny/crossref_metadata_2025 huggingface dataset:
One-Dimensional Nonlinear Seismic Response Analysis Using Strength-Controlled Constitutive Models: The Case of the Leaning Tower of Pisa’s Subsoil
Authors: Fiorentino Gabriele , Nuti Camillo , Squeglia Nunziante , Lavorato Davide , Stacul Stefano
Published: June 2018

The Leaning Tower of Pisa was built between 1173 and 1360 and began to lean at the beginning of its construction. Extensive investigations to reveal the causes of the tilting only began in the early 20th century. Although few earthquakes have been recorded, there is a renewed interest in the seismic behavior of the tower triggered by the availability of new data and technologies. This paper highlights the influence of using new strength-controlled constitutive models in case of 1D nonlinear response analysis. This is an aspect that has been poorly investigated. Most of the computer codes currently available for nonlinear seismic response analysis (SRA) of soil use constitutive models able to capture small-strain behavior, but the large-strain shear strength is left uncontrolled. This can significantly affect the assessment of a 1-D response analysis and the Leaning Tower’s subsoil can be useful for this study as it represents a well-documented and well-characterized site. After a geological and geotechnical description of the subsoil profile and a synthesis of available data, the seismic input is defined. One-dimensional SRAs were carried out by means of a computer code which considers an equivalent-linear soil modelling and two codes which assume nonlinear soil response and permit to use strength-controlled constitutive models. All the parameters were calibrated on the basis of the same soil data, therefore allowing for a direct comparison of the results.
Rehabilitation of Aging Urban Water Systems: Strategic Thinking Required
Authors: Katko Tapio S. , Hukka Jarmo J. , Juuti Petri S. , Rajala Riikka P.
Published: June 2018

This paper highlights the fundamental and invaluable role of water services in human settlements and community development. The paper aims at revealing the reasons behind aging infrastructure, the major challenge of the sector worldwide, and finding alternative strategies and means for resolving them. The authors argue that the problems of water services are largely related to management, institutions, organizations, and policies. In many ways, the requirement to see water services in a wider institutional framework is analogical to the proposed framework of Integrated Urban Water Management. The paper first explores the exceptionally long timeframe of water services management, followed by frameworks on core and non-core operations of water utilities in relation to the roles of major parties in municipal decision-making. For solving the major problems of water services both political and professional will is needed, educational programs are to be revised, and better rules of the game (institutions) are needed together with additional inputs on Research and Development activities.
Prediction of Emergency Department Re-Visits in Older Patients by the Identification of Senior at Risk (ISAR) Screening
Authors: Slankamenac Ksenija , Haberkorn Gertraud , Meyer Otto , Bischoff-Ferrari Heike A. , Keller Dagmar I.
Published: June 2018

The “Identification of Seniors at Risk” (ISAR) screening is a tool to identify seniors at risk of adverse outcomes. We investigated whether seniors with a positive ISAR screening have an increased risk of Emergency Department (ED) re-visits and health-service costs. In a pilot project, we enrolled 96 ED patients (≥70 years) who received an ISAR screening in the ED. We compared the rate of ED re-visits and in-hospital costs between ISAR positive (≥2 pts) and ISAR negative (<2 pts) patients. In some patients, a geriatrician performed a single Geriatric Consultation (GC) during the ED stay to assess older patients’ needs.32% of the study population had an unplanned ED re-visit (31 of 96). Fifty patients were ISAR positive (52%) and showed an increased risk of ED re-visits compared with ISAR negative patients (dds ratio (OR) 6.8, 95% confidence interval (CI) 2.2–21.0, p = 0.001). The positive ISAR screening tool fairly predicted ED re-visits in seniors (area under the curve (AUC) 0.711). A single GC during the ED stay did not reduce the risk of unplanned ED re-visits in ISAR positive patients (p = 0.80) ISAR positive patients with GC did not have higher in-hospital costs than ISAR negative patients without GC. Based on these findings, we aim to establish a comprehensive outpatient geriatric assessment program to identify relevant risk factors for ED re-visits and to recommend preventive strategies in ISAR positive ED seniors.
Strategies to Engage Adolescents in Digital Health Interventions for Obesity Prevention and Management
Authors: Partridge Stephanie R. , Redfern Julie
Published: June 2018

Obesity is one of the greatest health challenges facing today’s adolescents. Dietary interventions are the foundation of obesity prevention and management. As adolescents are digital frontrunners and early adopters of technology, digital health interventions appear the most practical modality for dietary behavior change interventions. Despite the rapid growth in digital health interventions, effective engagement with adolescents remains a pertinent issue. Key strategies for effective engagement include co-designing interventions with adolescents, personalization of interventions, and just-in-time adaptation using data from wearable devices. The aim of this paper is to appraise these strategies, which may be used to improve effective engagement and thereby improve the dietary behaviors of adolescents now and in the future.
Overflow Discharges and Flooding Areas from Flood Hydrographs Routing in Arda River, Greece
Authors: Angelidis Panagiotis , Maris Fotios , Kopasakis Kyriakos , Vasileiou Apostolos , Kotsovinos Nikos
Published: June 2018

Flooding is a natural disaster that damages infrastructure, properties, and may even cause loss of life. Major floods occur in the Arda river basin, which is shared between Greece and Bulgaria in Southeastern Europe. A flood warning system can sufficiently minimize adverse effects by helping to create a more successful and well-organized response plan. This paper presents an extensive numerical simulation of flood hydrograph routing between levees of the downstream section of the Arda river for floods with return periods from 2 to 10,000 years, using the one-dimensional software HEC-RAS. The main objective is to calculate the inundation areas, travel times of flood waves, water depths, water levels, flow velocities, and overflow volumes by simulating the hydraulic behavior of the Arda river outside its mountain watershed, where it flows through agricultural plane land with very mild slope. The great importance of the water level at the confluence of the Arda and Evros rivers (downstream boundary condition) has been pointed out for the regions near the confluence because the flow is the subcritical type. A significant finding of this work is the determination of the upper limit of the peak discharge hydrograph entering from the Arda to the Evros river to prevent the flooding of the Evros river. This finding is very important for the management of the flood flows of the Evros river, which is a major river with a complicated river system.
Application of Positive Matrix Factorization in the Identification of the Sources of PM2.5 in Taipei City
Authors: Ho Wen-Yuan , Tseng Kuo-Hsin , Liou Ming-Lone , Chan Chang-Chuan , Wang Chia-hung
Published: June 2018

Fine particulate matter (PM2.5) has a small particle size, which allows it to directly enter the respiratory mucosa and reach the alveoli and even the blood. Many countries are already aware of the adverse effects of PM2.5, and determination of the sources of PM2.5 is a critical step in reducing its concentration to protect public health. This study monitored PM2.5 in the summer (during the southwest monsoon season) of 2017. Three online monitoring systems were used to continuously collect hourly concentrations of key chemical components of PM2.5, including anions, cations, carbon, heavy metals, and precursor gases, for 24 h per day. The sum of the concentrations of each compound obtained from the online monitoring systems is similar to the actual PM2.5 concentration (98.75%). This result suggests that the on-line monitoring system of this study covers relatively complete chemical compounds. Positive matrix factorization (PMF) was adopted to explore and examine the proportion of each source that contributed to the total PM2.5 concentration. According to the source contribution analysis, 55% of PM2.5 can be attributed to local pollutant sources, and the remaining 45% can be attributed to pollutants emitted outside Taipei City. During the high-PM2.5-concentration (episode) period, the pollutant conversion rates were higher than usual due to the occurrence of vigorous photochemical reactions. Moreover, once pollutants are emitted by external stationary pollutant sources, they move with pollution air masses and undergo photochemical reactions, resulting in increases in the secondary pollutant concentrations of PM2.5. The vertical monitoring data indicate that there is a significant increase in PM2.5 concentration at high altitudes. High-altitude PM2.5 will descend to the ground and thereby affect the ground-level PM2.5 concentration.
Review of Research into Enterprise Bankruptcy Prediction in Selected Central and Eastern European Countries
Authors: Prusak Błażej
Published: June 2018

In developed countries, the first studies on forecasting bankruptcy date to the early 20th century. In Central and Eastern Europe, due to, among other factors, the geopolitical situation and the introduced economic system, this issue became the subject of researcher interest only in the 1990s. Therefore, it is worthwhile to analyze whether these countries conduct bankruptcy risk assessments and what their level of advancement is. The main objective of the article is the review and assessment of the level of advancement of bankruptcy prediction research in countries of the former Eastern Bloc, in comparison to the latest global research trends in this area. For this purpose, the method of analyzing scientific literature was applied. The publications chosen as the basis for the research were mainly based on information from the Google Scholar and ResearchGate databases during the period Q4 2016–Q3 2017. According to the author’s knowledge, this is the first such large-scale study involving the countries of the former Eastern Bloc—which includes the following states: Poland, Lithuania, Latvia, Estonia, Ukraine, Hungary, Russia, Slovakia, Czech Republic, Romania, Bulgaria, and Belarus. The results show that the most advanced research in this area is conducted in the Czech Republic, Poland, Slovakia, Estonia, Russia, and Hungary. Belarus Bulgaria and Latvia are on the other end. In the remaining countries, traditional approaches to predicting business insolvency are generally used.
3-D Morphological Change Analysis of a Beach with Seagrass Berm Using a Terrestrial Laser Scanner
Authors: Corbí Hugo , Riquelme Adrian , Megías-Baños Clara , Abellan Antonio
Published: June 2018

Along many Mediterranean coasts, the detached seagrass material of Posidonia oceanica creates seagrass berms that control the structure and morphodynamics of sandy beaches. Here, we show how Terrestrial Laser Scanner remote sensing data allows analyzing the 3-D morphologic change of beaches where this characteristic geomorphic structure is present. We propose a methodology for estimating accretion/erosion (almost −200 m3 in our study) by considering the sand dominated and seagrass berms as two independent elements. For this purpose, two different sampling dates (named scenarios A and B, before and after an erosive heavy storms period, respectively) recorded in a microtidal pocket-beach (300 m2) with these characteristic geomorphic structures have been modeled in 3-D. The present approach constitutes a cost-efficient, accurate, and quick tool to survey the sand volume in natural and artificial replenished beaches. The innovative approach, which can be considered as a conceptual and methodological starting point, can be useful to examine long-term and high-precision data sets in future studies of the morphodynamic evolution of these characteristic Mediterranean beaches.
Template Matching for Wide-Baseline Panoramic Images from a Vehicle-Borne Multi-Camera Rig
Authors: Ji Shunping , Yu Dawen , Hong Yong , Lu Meng
Published: June 2018

Automatic detection and locating of objects such as poles, traffic signs, and building corners in street scenes captured from a mobile mapping system has many applications. Template matching is a technique that could automatically recognise the counterparts or correspondents of an object from multi-view images. In this study, we aim at finding correspondents of an object from wide baseline panoramic images with large geometric deformations from sphere projection and significant systematic errors from multi-camera rig geometry. Firstly, we deduce the camera model and epipolar model of a multi-camera rig system. Then, epipolar errors are analysed to determine the search area for pixelwise matching. A low-cost laser scanner is optionally used to constrain the depth of an object. Lastly, several classic feature descriptors are introduced to template matching and evaluated on the multi-view panoramic image dataset. We propose a template matching method combining a fast variation of a scale-invariant feature transform (SIFT) descriptor. Our method experimentally achieved the best performance in terms of accuracy and efficiency comparing to other feature descriptors and the most recent robust template matching methods.
Analysis of Scattering Properties of Continuous Slow-Release Slicks on the Sea Surface Based on Polarimetric Synthetic Aperture Radar
Authors: Li Guannan , Li Ying , Liu Bingxin , Hou Yongchao , Fan Jianchao
Published: June 2018

This study employs polarimetric synthetic aperture radar (Pol-SAR) to examine the scattering properties of continuous slow-release oil slicks on the sea surface. The objective is to extract and analyze the general polarization scattering properties of continuous slow-release slicks, i.e., those slicks that consist of substances released at a fairly slow and relatively constant rate, and to determine the influence of the slick formation process on these properties. Using multi-polarization feature parameters derived from the averaged coherency matrix, we find that the scattering mechanisms related to the continuous slow-release slicks differ from those of anthropogenic slicks, possibly as a result of the multiple scattering mechanisms that occur between the interfaces formed by the thick slick layer. Combinations of entropy (H) and modified anisotropy (A12) are relatively robust parameters for identifying continuous slow-release slicks under different sea conditions, and may serve as a reference parameter for slick detection.
Efficient Parallel K Best Connected Trajectory (K-BCT) Query with GPGPU: A Combinatorial Min-Distance and Progressive Bounding Box Approach
Authors: Li Jing , Wang Xuantong , Zhang Tong , Xu You
Published: June 2018

Performing similarity analysis on trajectories consisting of massive numbers of tracking points is computationally challenging. We introduce a progressive minimum bounding rectangle (MBR) and minimum distance (MINDIST) approach to process the K Best Connected Trajectory (K-BCT) query, which aims to find the top K similarity trajectories to a given query trajectory. Our approach has three unique features to speed up the query. First, the approach builds a series of progressive MBRs from the query trajectory to determine the order of reference trajectories to identify the target top K reference trajectories at an earlier stage. Second, this method introduces a grid-based search method to speed up the matched point detection between two trajectories for similarity measures. Third, this approach further leverages the many-core computing power of Graphical Processing Unit (GPU) devices to perform the query in a parallel manner. We have conducted tests with ship tracking data and human movement data using GPU instances from Amazon Web Services. Preliminary results indicate that (a) parallel computing has greatly improved the efficiency of the query, and (b) our optimized approach can further speedup the computation compared to parallel implementations.
Extraction and Spatial–Temporal Evolution of Urban Fringes: A Case Study of Changchun in Jilin Province, China
Authors: Chang Shouzhi , Jiang Qigang , Wang Zongming , Xu Sujuan , Jia Mingming
Published: June 2018

An urban fringe area, depicted as a typical ecotone, is a region where both social and environmental problems are concentrated. Identifying and evaluating the spatial–temporal characteristics of urban fringe areas is significant for future development. On the basis of the land use data extracted from remote sensing data, the Shannon diversity index (SHDI) of each unit can be calculated, and identifying the urban fringe area by the breakpoint method is reliable. By using the rapidly growing Changchun as example, this study identifies the urban fringe of Changchun in 1995, 2005, and 2015 by applying the breakpoint method. The expansion amount, change mode, direction of expansion, landscape, and influence factors are evaluated. Policy and planning are the main factors influencing the development direction of the Changchun fringe area. The urban fringe area of Changchun City is extended to the east, southeast, and north. From 1995 to 2005, the outlying expansion was the dominant type. The main change mode was the infilling type due to the reduction of available land, from 2005 to 2015. In accordance with the landscape metrics, the landscape within the urban fringe transformed from fragmentation to regularization. The development of the urban fringe also transformed from a disorderly to an orderly manner.
Seamless Upscaling of the Field-Measured Grassland Aboveground Biomass Based on Gaussian Process Regression and Gap-Filled Landsat 8 OLI Reflectance
Authors: Yin Gaofei , Li Ainong , Wu Chaoyang , Wang Jiyan , Xie Qiaoyun , Zhang Zhengjian , Nan Xi , Jin Huaan , Bian Jinhu , Lei Guangbin
Published: June 2018

The spatially explicit aboveground biomass (AGB) generated through upscaling field measurements is critical for carbon cycle simulation and optimized management of grasslands. However, the spatial gaps that exist in the optical remote sensing data, underutilization of the multispectral data cube and unavailability of uncertainty information hinder the generation of seamless and accurate AGB maps. This study proposes a novel framework to address the above challenges. The proposed framework filled the spatial gaps in the remote sensing data via the consistent adjustment of the climatology to actual observations (CACAO) method. Gaussian process regression (GPR) was used to fully exploit the multispectral data cube and generated the pixelwise uncertainty concurrent with the AGB estimation. A case study in a 100 km × 100 km area located in the Zoige Plateau, China was used to evaluate this framework. The results show that the CACAO method can fill almost all of the gaps, accounting for 93.1% of the study area, with satisfactory accuracy. The generated AGB map from the GPR was characterized by a relatively high accuracy (R2 = 0.64, RMSE = 48.13 g/m2) compared to vegetation index-derived ones, and was accompanied by a corresponding uncertainty map that provides a new source of information on the credibility of each pixel. This study demonstrates the potential of the joint use of gap-filling and machine-learning methods to generate spatially explicit AGB.
Characterizing Light Pollution Trends across Protected Areas in China Using Nighttime Light Remote Sensing Data
Authors: Jiang Wei , He Guojin , Leng Wanchun , Long Tengfei , Wang Guizhou , Liu Huichan , Peng Yan , Yin Ranyu , Guo Hongxiang
Published: June 2018

Protected areas (PAs) with natural, ecological, and cultural value play important roles related to biological processes, biodiversity, and ecosystem services. Over the past four decades, the spatial range and intensity of light pollution in China has experienced an unprecedented increase. Few studies have been documented on the light pollution across PAs in China, especially in regions that provide a greater amount of important biodiversity conservation. Here, nighttime light satellite images from the Defense Meteorological Satellite Program Operational Linescan System (DMSP-OLS) were selected to characterize light pollution trends across PAs using nighttime light indexes and hot spot analysis, and then the light pollution changes in PAs were classified. Furthermore, the causes of light pollution changes in PAs were determined using high-resolution satellite images and statistical data. The results showed the following: (1) Approximately 57.30% of PAs had an increasing trend from 1992 to 2012, and these PAs were mainly located in the eastern region, the central region, and a small part of the western region of China. Hot spot analysis showed that the patterns of change for the total night light and night light mean had spatial agglomeration characteristics; (2) The PAs affected by light pollution changes were divided into eight classes, of which PAs with stable trends accounted for 41%, and PAs with high increasing trends accounted for 10%. PAs that had high increasing trends with low density accounted for the smallest amount, i.e., only 1%; (3) The factors influencing light pollution changes in PAs included the distance to urban areas, mineral exploitation, and tourism development and the migration of residents. Finally, based on the status of light pollution encroachment into PAs, strategies to control light pollution and enhance the sustainable development of PAs are recommended.
Shaking Maps Based on Cumulative Absolute Velocity and Arias Intensity: The Cases of the Two Strongest Earthquakes of the 2016–2017 Central Italy Seismic Sequence
Authors: Costanzo Antonio
Published: June 2018

By referring to the two strongest earthquakes of the 2016–2017 Central Italy seismic sequence, this paper presents a procedure to make shaking maps through empirical relationships between macroseismic intensity and ground-motion parameters. Hundreds of waveforms were processed to obtain instrumental ground-motion features which could be correlated with the potential damage intensities. To take into account peak value, frequency, duration, and energy content, which all contribute to damage, cumulative absolute velocity and Arias intensity were used to quantify the features of the ground motion. Once these parameters had been calculated at the recording sites, they were interpolated through geostatistical techniques on the whole struck area. Finally, empirical relationships were used for mapping intensities, i.e., potential effects on the built environment. The results referred to both earthquake scenarios that were analyzed and were also used for assessing the influence of the spatial coverage of the instrumental network. In fact, after the first events, the Italian seismic network was subjected to the addition and thickening of sensors in the epicentral area, especially. The results obtained by models only dependent on ground-motion parameters or even on the epicentral distance were compared with the official ShakeMaps and the observed intensities for assessing their reliability. Finally, some suggestions are proposed to improve the procedure that could be used for rapidly assessing ground shaking and mapping damage potential producing useful information for non-expert audience.
Mapping Urban Land Use at Street Block Level Using OpenStreetMap, Remote Sensing Data, and Spatial Metrics
Authors: Grippa Taïs , Georganos Stefanos , Zarougui Soukaina , Bognounou Pauline , Diboulo Eric , Forget Yann , Lennert Moritz , Vanhuysse Sabine , Mboga Nicholus , Wolff Eléonore
Published: June 2018

Up-to-date and reliable land-use information is essential for a variety of applications such as planning or monitoring of the urban environment. This research presents a workflow for mapping urban land use at the street block level, with a focus on residential use, using very-high resolution satellite imagery and derived land-cover maps as input. We develop a processing chain for the automated creation of street block polygons from OpenStreetMap and ancillary data. Spatial metrics and other street block features are computed, followed by feature selection that reduces the initial datasets by more than 80%, providing a parsimonious, discriminative, and redundancy-free set of features. A random forest (RF) classifier is used for the classification of street blocks, which results in accuracies of 84% and 79% for five and six land-use classes, respectively. We exploit the probabilistic output of RF to identify and relabel blocks that have a high degree of uncertainty. Finally, the thematic precision of the residential blocks is refined according to the proportion of the built-up area. The output data and processing chains are made freely available. The proposed framework is able to process large datasets, given that the cities in the case studies, Dakar and Ouagadougou, cover more than 1000 km2 in total, with a spatial resolution of 0.5 m.
Protective Effect of Octylmethoxycinnamate against UV-Induced Photoaging in Hairless Mouse via the Regulation of Matrix Metalloproteinases
Authors: Kim So Young , Lamichhane Santosh , Ju Jung-Hun , Yun Jaesuk
Published: June 2018

Ultraviolet (UV) irradiation damages skin and produces symptoms of photoaging, such as thickening, rough texture, wrinkles, and pigmentation. However, the cellular and molecular mechanisms underlying photoaging induced by chronic UV irradiation are not yet fully understood. Matrix metalloproteinases (MMPs) have been reported to be involved in the response to UV irradiation. In this study, we examined the effects of the sunscreen agent Octylmethoxycinnamate (OMC) on photoaging of the skin induced by chronic UV exposure in hairless albino Crl:SKH1-Hrhr (SKH-1) mice. We demonstrated that the expression of MMPs was elevated by UV irradiation, whereas the topical application of OMC inhibited the upregulation of MMPs. Furthermore, UV-induced wrinkle formation was decreased by OMC treatment. These results suggest that OMC is a potential agent for the prevention and treatment of skin photoaging.
The Separation of Microalgae Using Dean Flow in a Spiral Microfluidic Device
Authors: Lee Ming-Lung , Yao Da-Jeng
Published: June 2018

A cell-in-droplet encapsulation using Dean flow in a spiral microfluidic device was applied to separate microalgae. In recent years, researchers have been interested in separating micro particles using microfluidic chips because of its great advantages in relation to various applications such as in biotechnology, medical examination, and cell studies. The main disadvantage of these microfluidic chips is particle clogging that decreases the separation yield, which then creates difficulties during the investigation of the particles. The microfluidic chip that is introduced in this work is a combination of two distinct designs—a spiral microchannel design to separate microalgae of various sizes, and a microdroplet generation design for cell encapsulation. The yield of the separation is enhanced through the concept of dominant forces (Dean drag force and lift force) in a spiral microchannel design, together with a design of the microdroplet generation that narrows the volume to facilitate cell observation. We report the development of cells, particle separation, and microdroplet generation. Using the spiral microchannel design can solve the clogging problem by distributing the microalgae evenly for the microdroplet generation section. A spiral microfluidics design was used as a separator for the different sized particles and a microdroplets generation design was used to encapsulate the separated particles. As for the design for the microdroplets generation section, a 3-way microchannel was designed. In this research, two kinds of microalgae have been used: the smaller one is chlorella vulgaris and the bigger one is cosmarium. Because of all of these benefits, this device might be an alternative for cell applications using droplet-based platforms. With a different channel height design, the separation efficiency for Chlorella vulgaris is about 75–80% and for Cosmarium is about 60–72%.
Experimental Investigation of the Time Course Effects of Acute Exercise on False Episodic Memory
Authors: Siddiqui Ali , Loprinzi Paul D.
Published: June 2018

Previous experimental work suggests that acute exercise may positively influence the accurate recall of past episodic events. However, few studies have examined whether acute exercise also reduces the number of false episodic memories. We evaluated this paradigm in conjunction with an examination of the temporal effects of acute exercise, which have previously been shown to play an important role in subserving episodic memory function. Twenty young adults participated in three experimental visits, including a non-exercise control visit, a visit involving an acute bout (20 min) of moderate-intensity exercise occurring prior to the memory task, and a visit involving an acute bout of exercise occurring during the encoding of the memory task. All visits were counterbalanced and occurred at least 24 h apart. The Deese–Roediger–McDermott (DRM) Paradigm, involving a separate word list trial for each visit, was employed to assess accurate and false episodic memory recall. For each visit, a short-term (immediate recall) and a long-term (25-min delay) memory recall was assessed. For both time points, the visit that involved exercise prior to encoding resulted in better short-term and long-term memory function (F(2) = 11.56, p < 0.001, η2p = 0.38). For both time points, the control visit resulted in a greater number of false memories. These findings suggest that acute moderate-intensity exercise may help to increase the accurate recall of past episodic memories and may help to reduce the rate of false memories.
Tobramycin-Linked Efflux Pump Inhibitor Conjugates Synergize Fluoroquinolones, Rifampicin and Fosfomycin against Multidrug-Resistant Pseudomonas aeruginosa
Authors: Yang Xuan , Domalaon Ronald , Lyu Yinfeng , Zhanel George G. , Schweizer Frank
Published: June 2018

In this study, we examined the in vitro effect of tobramycin-efflux pump inhibitor (TOB-EPI) conjugates in combinations with fluoroquinolones, rifampicin and fosfomycin on the growth of multi-drug resistant (MDR) and extremely-drug resistant (XDR) Pseudomonas aeruginosa. The TOB-EPI conjugates include tobramycin covalently linked to 1-(1-naphthylmethyl)-piperazine (NMP) (1), paroxetine (PAR) (2) and a dibasic peptide analogue of MC-04,124 (DBP) (3). Potent synergism was found for combinations of TOB-NMP (1), TOB-PAR (2) or TOB-DBP (3) with either fluoroquinolones (moxifloxacin, ciprofloxacin), rifampicin or fosfomycin against a panel of multidrug-resistant/extensively drug-resistant (MDR/XDR) P. aeruginosa clinical isolates. In the presence of ≤8 mg/L (6.1–7.2 µM) (≤¼ × MICadjuvant) concentration of the three conjugates, the MIC80 of moxifloxacin, ciprofloxacin, rifampicin and fosfomycin were dramatically reduced. Furthermore, the MIC80 of rifampicin (0.25–0.5 mg/L) and fosfomycin (8–16 mg/L) were reduced below their interpretative susceptibility breakpoints. Our data confirm the ability of TOB-NMP (1), TOB-PAR (2) and TOB-DBP (3) conjugates to strongly synergize with moxifloxacin, ciprofloxacin, rifampicin and fosfomycin against MDR/XDR P. aeruginosa. These synergistic combinations warrant further studies as there is an urgent need to develop new strategies to treat drug-resistant P. aeruginosa infections.
Fisher Vector Coding for Covariance Matrix Descriptors Based on the Log-Euclidean and Affine Invariant Riemannian Metrics
Authors: Ilea Ioana , Bombrun Lionel , Said Salem , Berthoumieu Yannick
Published: June 2018

This paper presents an overview of coding methods used to encode a set of covariance matrices. Starting from a Gaussian mixture model (GMM) adapted to the Log-Euclidean (LE) or affine invariant Riemannian metric, we propose a Fisher Vector (FV) descriptor adapted to each of these metrics: the Log-Euclidean Fisher Vectors (LE FV) and the Riemannian Fisher Vectors (RFV). Some experiments on texture and head pose image classification are conducted to compare these two metrics and to illustrate the potential of these FV-based descriptors compared to state-of-the-art BoW and VLAD-based descriptors. A focus is also applied to illustrate the advantage of using the Fisher information matrix during the derivation of the FV. In addition, finally, some experiments are conducted in order to provide fairer comparison between the different coding strategies. This includes some comparisons between anisotropic and isotropic models, and a estimation performance analysis of the GMM dispersion parameter for covariance matrices of large dimension.
Failure of Grass Covered Flood Defences with Roads on Top Due to Wave Overtopping: A Probabilistic Assessment Method
Authors: Aguilar-López Juan P. , Warmink Jord J. , Bomers Anouk , Schielen Ralph M. J. , Hulscher Suzanne J. M. H.
Published: June 2018

Hard structures, i.e., roads, are commonly found over flood defences, such as dikes, in order to ensure access and connectivity between flood protected areas. Several climate change future scenario studies have concluded that flood defences will be required to withstand more severe storms than the ones used for their original design. Therefore, this paper presents a probabilistic methodology to assess the effect of a road on top of a dike: it gives the failure probability of the grass cover due to wave overtopping over a wide range of design storms. The methodology was developed by building two different dike configurations in computational fluid dynamics Navier–Stokes solution software; one with a road on top and one without a road. Both models were validated with experimental data collected from field-scale experiments. Later, both models were used to produce data sets for training simpler and faster emulators. These emulators were coupled to a simplified erosion model which allowed testing storm scenarios which resulted in local scouring conditioned statistical failure probabilities. From these results it was estimated that the dike with a road has higher probabilities (5 × 10−5 > Pf >1 × 10−4) of failure than a dike without a road (Pf < 1 × 10−6) if realistic grass quality spatial distributions were assumed. The coupled emulator-erosion model was able to yield realistic probabilities, given all the uncertainties in the modelling process and it seems to be a promising tool for quantifying grass cover erosion failure.
Fuzzy Semi-Metric Spaces
Authors: Wu Hsien-Chung
Published: June 2018

The T1-spaces induced by the fuzzy semi-metric spaces endowed with the special kind of triangle inequality are investigated in this paper. The limits in fuzzy semi-metric spaces are also studied to demonstrate the consistency of limit concepts in the induced topologies.
Total Controllability of the Second Order Semi-Linear Differential Equation with Infinite Delay and Non-Instantaneous Impulses
Authors: Chalishajar Dimplekumar N. , Kumar Avadhesh
Published: June 2018

In this manuscript, a stronger concept of exact controllability called Total Controllability has been introduced. Sufficient conditions have been established for the total controllability of the proposed problem. The proposed control problem is a second-order semi-linear differential equation with infinite delay and non-instantaneous impulses. The tools for study include the strongly continuous cosine family and Sadovskii’s fixed point theorem. The cosine family and the nonlinear function associated with the system are assumed to be non-compact. In addition, the total controllability of an integrodifferential problem has been investigated. Finally, an example is provided to illustrate the analytical findings.
Qualitative Analysis of a Dengue Fever Model
Authors: Gbadamosi Babatunde , Ojo Mayowa , Oke Segun , Matadi Maba
Published: June 2018

In this paper, a deterministic mathematical model of the Dengue virus with a nonlinear incidence function in a population is presented and rigorously analysed. The model incorporates control measures at the aquatic and adult stages of the vector (mosquito). The stability of the system is analysed for the disease-free equilibrium and the existence of endemic equilibria under certain conditions. The local stability of the Dengue-free equilibrium is investigated via the threshold parameter (reproduction number) that was obtained using the next-generation matrix techniques. The Routh–Hurwitz criterion, along with Descartes’ rule of signs change, established the local asymptotically stability of the model whenever R0<1 and was unstable otherwise. The comparison theorem was used to establish the global asymptomatically stability of the model.
Pain Modulation after Oromucosal Cannabinoid Spray (SATIVEX®) in Patients with Multiple Sclerosis: A Study with Quantitative Sensory Testing and Laser-Evoked Potentials
Authors: Turri Mara , Teatini Francesco , Donato Francesco , Zanette Giampietro , Tugnoli Valeria , Deotto Luciano , Bonetti Bruno , Squintani Giovanna
Published: June 2018

Background. Delta-9-tetrahydrocannabinol (THC)/cannabidiol (CBD) (nabiximols or Sativex®) is an oromucosal spray formulation containing THC and CBD at an approximately 1:1 fixed ratio. Its administration for the treatment of pain in patients with multiple sclerosis (MS) has been established. MS patients generally complain of different kinds of pain, including spasticity-related and neuropathic pain. In this study, we compared and evaluated pain modulation and thermal/pain threshold of MS patients before and after THC/CBD administration. Methods. 19 MS patients underwent clinical examination, numerical rating scale (NRS), quantitative sensory testing (QST), and laser-evoked potentials (LEPs) before and after 1 month of therapy. Psychophysiological and neurophysiological data were compared to sex- and age-matched controls. Results. Patients reported a significant reduction in pain. We found statistically significant differences in LEP parameters between patients and controls but no significant change in LEP measures after THC/CBD therapy. Cold and heat detection thresholds were altered in patients but did not change after THC/CBD therapy. There was a significant increase in cold pain threshold by hand stimulation and a significant reduction in abnormal cold perception thresholds. Conclusions. Our results indicate that Sativex® therapy provides pain relief in MS patients and suggest that it might modulate peripheral cold-sensitive TRP channels.
Characterization of 17-4PH Single Tracks Produced at Different Parametric Conditions towards Increased Productivity of LPBF Systems—The Effect of Laser Power and Spot Size Upscaling
Authors: Makoana Nkutwane Washington , Yadroitsava Ina , Möller Heinrich , Yadroitsev Igor
Published: June 2018

Global industrial adoption of laser-based powder bed fusion (LPBF) technology is still limited by the production speed, the size of the build envelope, and therefore the maximum part size that can be produced. The cost of LPBF can be driven down further by improving the build rates without compromising structural integrity. A common approach is that the build rate can be improved by increasing the laser power and beam diameter to instantly melt a large area of powder, thus reducing the scanning time for each layer. The aim of this study was to investigate the aspects of upscaling LPBF processing parameters on the characteristic formation of stable single tracks, which are the primary building blocks for this technology. Two LPBF systems operating independently, using different parameter regimes, were used to produce the single tracks on a solid substrate deposited with a thin powder layer. The results obtained indicate that higher laser power and spot size can be used to produce stable tracks while the linear energy input is increased. It was also shown statistically that the geometrical characteristics of single tracks are mainly affected by the laser power and scanning speed during the scanning of a thin powder layer.
PBP4: A New Perspective on Staphylococcus aureus β-Lactam Resistance
Authors: Da Costa Thaina M. , De Oliveira Carolina R. , Chambers Henry F. , Chatterjee Som S.
Published: June 2018

β-lactam antibiotics are excellent drugs for treatment of staphylococcal infections, due to their superior efficacy and safety compared to other drugs. Effectiveness of β-lactams is severely compromised due to resistance, which is widespread among clinical strains of Staphylococcus aureus. β-lactams inhibit bacterial cells by binding to penicillin binding proteins (PBPs), which perform the penultimate steps of bacterial cell wall synthesis. Among PBPs of S. aureus, PBP2a has received the most attention for the past several decades due to its preeminent role in conferring both high-level and broad-spectrum resistance to the entire class of β-lactam drugs. Studies on PBP2a have thus unraveled incredible details of its mechanism of action. We have recently identified that an uncanonical, low molecular weight PBP of S. aureus, PBP4, can also provide high-level and broad-spectrum resistance to the entire class of β-lactam drugs at a level similar to that of PBP2a. The role of PBP4 has typically been considered not so important for β-lactam resistance of S. aureus, and as a result its mode of action remains largely unknown. In this article, we review our current knowledge of PBP4 mediating β-lactam resistance in S. aureus.
One-Dimension Diffusion Preparation of Concentration-Gradient Fe2O3/SiO2 Aerogel
Authors: Zhang Ting , Wang Haoran , Zhou Bin , Ji Xiujie , Wang Hongqiang , Du Ai
Published: June 2018

Concentration-gradient Fe2O3/SiO2 aerogels were prepared by placing an MTMS (methyltrimethoxysilane)-derived SiO2 aerogel on an iron gauze with an HCl atmosphere via one-dimensional diffusion, ammonia-atmosphere fixing, supercritical fluid drying and thermal treatment. The energy dispersive spectra show that the Fe/Si molar ratios change gradually from 2.14% to 18.48% with a height of 40 mm. Pore-size distribution results show that the average pore size of the sample decreases from 15.8 nm to 3.1 nm after diffusion. This corresponds well with TEM results, indicating a pore-filling effect of the Fe compound. In order to precisely control the gradient, diffusion kinetics are further studied by analyzing the influence of time and position on the concentration of the wet gel. At last, it is found that the diffusion process could be fitted well with the one-dimensional model of Fick’s second law, demonstrating the feasibility of the precise design and control of the concentration gradient.
Solid-State Highly Efficient DR Mono and Poly-dicyano-phenylenevinylene Fluorophores
Authors: Panunzi Barbara , Diana Rosita , Concilio Simona , Sessa Lucia , Shikler Rafi , Nabha Shiran , Tuzi Angela , Caruso Ugo , Piotto Stefano
Published: June 2018

An efficient deep red (DR)-emitting organic solid based on a dicyano-phenylenevinylene derivative was reported. The structural and spectroscopic properties of the solid have been described in terms of crystallographic data and time-dependent DFT analysis. A noteworthy fluorescence quantum yield of 53% was observed for the brightest emitter cast into solid films. This result can be explained in terms of the aggregation-induced emission (AIE) effect.
Wunderkammers: Powerful Metaphors for ‘Tangible’ Experiential Knowledge Building
Authors: Charlton Patricia , Koumpis Adamantios , Kouroupetroglou Christos , Grenon Muriel
Published: June 2018

Research problem: The paper identifies the need to support powerful metaphors that capture innovations of new emerging human computer interaction (HCI) technologies and innovative question and answering (Q&A) systems in the context of spatial learning and inquiry-based learning in education. Aim/goals of the research: Explore the potential of ‘Wunderkammer’ (curiosity cabinet) as a powerful metaphor to design new types of learning experiences catering for an ecology of artefacts (real of virtual objects) to provide a holistic context for educators to share and extend learning in action. Conclusions: We provide insight into the emergence of smart interactive objects with different types of sensors that can potentially support everyday life and the increasing access to new visual experiences through augment reality and virtual reality, for new types of tangible knowledge building that can be personalised and shared. This reshaping of human centred design and creating new experiences through tangible creations that externalize in real time and through new materials, the creative power of the ‘imaginations of movement’ provides new user experience design thinking through the concept of powerful metaphors, to provide core design requirements where the blending of worlds is common place.
Manipulation and Investigation of Uniformly-Spaced Nanowire Array on a Substrate via Dielectrophoresis and Electrostatic Interaction
Authors: Choi U Hyeok , Park Ji Hun , Kim Jaekyun
Published: June 2018

Directed-assembly of nanowires on the dielectrics-covered parallel electrode structure is capable of producing uniformly-spaced nanowire array at the electrode gap due to dielectrophoretic nanowire attraction and electrostatic nanowire repulsion. Beyond uniformly-spaced nanowire array formation, the control of spacing in the array is beneficial in that it should be the experimental basis of the precise positioning of functional nanowires on a circuit. Here, we investigate the material parameters and bias conditions to modulate the nanowire spacing in the ordered array, where the nanowire array formation is readily attained due to the electrostatic nanowire interaction. A theoretical model for the force calculation and the simulation of the induced charge in the assembled nanowire verifies that the longer nanowires on thicker dielectric layer tend to be assembled with a larger pitch due to the stronger nanowire-nanowire electrostatic repulsion, which is consistent with the experimental results. It was claimed that the stronger dielectrophoretic force is likely to attract more nanowires that are suspended in solution at the electrode gap, causing them to be less-spaced. Thus, we propose a generic mechanism, competition of dielectrophoretic and electrostatic force, to determine the nanowire pitch in an ordered array. Furthermore, this spacing-controlled nanowire array offers a way to fabricate the high-density nanodevice array without nanowire registration.
Improved Magneto-Optic Surface Plasmon Resonance Biosensors
Authors: Rizal Conrad , Pisana Simone , Hrvoic Ivan
Published: June 2018

The magneto-optic (MO) characteristics and sensing performance of noble metal (Ag, Au, Cu) or transition metal (Fe, Ni, Co) single layers and Ag/Co or Au/Co bilayers have been studied and compared in both the standard plasmonic and MO plasmonic configurations at two different wavelengths (632.8 nm and 785 nm) and in two different sensing media (air and water). The sensing performance is found to be medium-specific and lower in biosensor-relevant water-based media. The sensitivities of MO-SPR sensors is found to be superior to SPR sensors in all cases. This enhancement in sensitivity means the detection limit of this class of transducers can be substantially improved by tuning Au/Co layer thickness, wavelength, and incident angle of optical radiation. The optimized bilayer showed an enhancement in sensitivity by over 30× in air and 9× in water as compared to the conventional Au SPR configuration. Notably, the best performance is 3× above that of MO-SPR sensors coupled to a photonic crystal previously reported in the literature and is found when the ferromagnetic layer is furthest from the sensing medium, as opposed to typical MO-SPR configurations. This proposed structure is attractive for next-generation biosensors.