bluuebunny/crossref_metadata_2025 huggingface dataset:
Paper-Based ZnS:Cu Alternating Current Electroluminescent Devices for Current Humidity Sensors with High–Linearity and Flexibility
Authors: He Yaqin , Zhang Mengyao , Zhang Nan , Zhu Danrong , Huang Chun , Kang Ling , Zhou Xiaofeng , Hu Menghan , Zhang Jian
Published: October 2019

Humidity sensors are indispensable for various electronic systems and instrumentations. To develop a new humidity sensing mechanism is the key for the next generation of sensor technology. In this work, a novel flexible paper-based current humidity sensor is proposed. The developed alternating current electroluminescent devices (ACEL) consist of the electroless plating Ni on filter paper and silver nanowires (AgNWs) as the bottom and upper electrodes, and ZnS:Cu as the phosphor layer, respectively. The proposed humidity sensor is based on ACEL with the paper substrate and the ZnS:Cu phosphor layer as the humidity sensing element. The moisture effect on the optical properties of ACELs has been studied firstly. Then, the processing parameters of the paper-based ACELs such as electroless plated bottom electrode and spin-coated phosphor layer as a function of the humidity-sensitive characteristics are investigated. The sensing mechanism of the proposed sensor has been elucidated based on the Q ~ V analysis. The sensor exhibits an excellent linearity ( R 2 = 0.99965 ) within the humidity range from 20% to 90% relative humidity (RH) and shows excellent flexibility. We also demonstrate its potential application in postharvest preservation where the EL light is used for preservation and the humidity can be monitored simultaneously through the current.
A Cooperative Machine Learning Approach for Pedestrian Navigation in Indoor IoT
Authors: Jalal Abadi Marzieh , Luceri Luca , Hassan Mahbub , Chou Chun Tung , Nicoli Monica
Published: October 2019

This paper presents a system based on pedestrian dead reckoning (PDR) for localization of networked mobile users, which relies only on sensors embedded in the devices and device- to-device connectivity. The user trajectory is reconstructed by measuring step by step the user displacements. Though step length can be estimated rather accurately, heading evaluation is extremely problematic in indoor environments. Magnetometer is typically used, however measurements are strongly perturbed. To improve the location accuracy, this paper proposes a novel cooperative system to estimate the direction of motion based on a machine learning approach for perturbation detection and filtering, combined with a consensus algorithm for performance augmentation by cooperative data fusion at multiple devices. A first algorithm filters out perturbed magnetometer measurements based on a-priori information on the Earth’s magnetic field. A second algorithm aggregates groups of users walking in the same direction, while a third one combines the measurements of the aggregated users in a distributed way to extract a more accurate heading estimate. To the best of our knowledge, this is the first approach that combines machine learning with consensus algorithms for cooperative PDR. Compared to other methods in the literature, the method has the advantage of being infrastructure-free, fully distributed and robust to sensor failures thanks to the pre-filtering of perturbed measurements. Extensive indoor experiments show that the heading error is highly reduced by the proposed approach thus leading to noticeable enhancements in localization performance.
A Gaussian Process Model for Color Camera Characterization: Assessment in Outdoor Levantine Rock Art Scenes
Authors: Molada-Tebar Adolfo , Riutort-Mayol Gabriel , Marqués-Mateu Ángel , Lerma José Luis
Published: October 2019

In this paper, we propose a novel approach to undertake the colorimetric camera characterization procedure based on a Gaussian process (GP). GPs are powerful and flexible nonparametric models for multivariate nonlinear functions. To validate the GP model, we compare the results achieved with a second-order polynomial model, which is the most widely used regression model for characterization purposes. We applied the methodology on a set of raw images of rock art scenes collected with two different Single Lens Reflex (SLR) cameras. A leave-one-out cross-validation (LOOCV) procedure was used to assess the predictive performance of the models in terms of CIE XYZ residuals and Δ E a b * color differences. Values of less than 3 CIELAB units were achieved for Δ E a b * . The output sRGB characterized images show that both regression models are suitable for practical applications in cultural heritage documentation. However, the results show that colorimetric characterization based on the Gaussian process provides significantly better results, with lower values for residuals and Δ E a b * . We also analyzed the induced noise into the output image after applying the camera characterization. As the noise depends on the specific camera, proper camera selection is essential for the photogrammetric work.
EMV-Compatible Offline Mobile Payment Protocol with Mutual Authentication
Authors: Luo Jia-Ning , Yang Ming-Hour
Published: October 2019

In 2014, Yang proposed a method to enhance the current EMV credit card protocol (EPMAR). However, the protocol ignores the exceeding of a credit quota caused by multiple offline transactions, with the result that the amount spent can exceed the risk control scope. In this paper, we proposed an EMV-compatible offline mobile payment protocol with mutual authentication (EOPMA) to enhance EPMAR. In EOPMA, we use the reverse hash chain technique to guarantee the payment, which solves the problem of credit quotas getting exceeded because of multiple offline payments. During a transaction, in addition to payment for merchandise, an offline authorization certificate for the transaction is sent to the merchant. The merchant can verify the correctness of the transaction in real time. Our protocol is compatible with the EMV standard, which is applicable to the retail environment of numerous merchants and effectively, making EMV transactions more secure and reliable. We use numerical analysis to examine the security and performance of the protocols. We formally check the correctness of EOPMA by using the Gong–Needham–Yahalom logic.
Identification of Bicycling Periods Using the MicroPEM Personal Exposure Monitor
Authors: Chew Robert , Thornburg Jonathan , Jack Darby , Smith Cara , Yang Qiang , Chillrud Steven
Published: October 2019

Exposure assessment studies are the primary means for understanding links between exposure to chemical and physical agents and adverse health effects. Recently, researchers have proposed using wearable monitors during exposure assessment studies to obtain higher fidelity readings of exposures actually experienced by subjects. However, limited research has been conducted to link a wearer’s actions to periods of exposure, a necessary step for estimating inhaled dosage. To aid researchers in these settings, we developed a machine learning model for identifying periods of bicycling activity using passively collected data from the RTI MicroPEM wearable exposure monitor, a lightweight device capable of continuously sampling both air pollution levels and accelerometry parameters. Our best performing model identifies biking activity with a mean leave-one-session-out (LOSO) cross-validation F1 score of 0.832 (unweighted) and 0.979 (weighted). Accelerometer derived features contributed greatly to the model performance, as well as temporal smoothing of the predicted activities. Additionally, we found competitive activity recognition can occur with even relatively low sampling rates, suggesting suitability for exposure assessment studies where continuous data collection for long periods (without recharge) are needed to capture realistic daily routines and exposures.
A Magnetically Tunable Check Valve Applied to a Lab-on-Chip Nitrite Sensor
Authors: Morgan Sean C. , Hendricks Andre D. , Seto Mae L. , Sieben Vincent J.
Published: October 2019

Presented here is the fabrication and characterization of a tunable microfluidic check valve for use in marine nutrient sensing. The ball-style valve makes use of a rare-earth permanent magnet, which exerts a pulling force to ensure it remains passively sealed until the prescribed cracking pressure is met. By adjusting the position of the magnet, the cracking pressure is shown to be customizable to meet design requirements. Further applicability is shown by integrating the valve into a poly(methyl methacrylate) (PMMA) lab-on-chip device with an integrated optical absorbance cell for nitrite detection in seawater. Micro-milling is used to manufacture both the valve and the micro-channel structures. The valve is characterized up to a flow rate of 14 mL min−1 and exhibits low leakage rates at high back pressures (<2 µL min−1 at ~350 kPa). It is low cost, requires no power, and is easily implemented on microfluidic platforms.
Measurement of the Three-Dimensional Shape of Discontinuous Specular Objects Using Infrared Phase-Measuring Deflectometry
Authors: Chang Caixia , Zhang Zonghua , Gao Nan , Meng Zhaozong
Published: October 2019

Phase-measuring deflectometry (PMD)-based methods have been widely used in the measurement of the three-dimensional (3D) shape of specular objects, and the existing PMD methods utilize visible light. However, specular surfaces are sensitive to ambient light. As a result, the reconstructed 3D shape is affected by the external environment in actual measurements. To overcome this problem, an infrared PMD (IR-PMD) method is proposed to measure specular objects by directly establishing the relationship between absolute phase and depth data for the first time. Moreover, the proposed method can measure discontinuous surfaces. In addition, a new geometric calibration method is proposed by combining fringe projection and fringe reflection. The proposed IR-PMD method uses a projector to project IR sinusoidal fringe patterns onto a ground glass, which can be regarded as an IR digital screen. The IR fringe patterns are reflected by the measured specular surfaces, and the deformed fringe patterns are captured by an IR camera. A multiple-step phase-shifting algorithm and the optimum three-fringe number selection method are applied to the deformed fringe patterns to obtain wrapped and unwrapped phase data, respectively. Then, 3D shape data can be directly calculated by the unwrapped phase data on the screen located in two positions. The results here presented validate the effectiveness and accuracy of the proposed method. It can be used to measure specular components in the application fields of advanced manufacturing, automobile industry, and aerospace industry.
MEMS Hydrophone Signal Denoising and Baseline Drift Removal Algorithm Based on Parameter-Optimized Variational Mode Decomposition and Correlation Coefficient
Authors: Yan Huichao , Xu Ting , Wang Peng , Zhang Linmei , Hu Hongping , Bai Yanping
Published: October 2019

Underwater acoustic technology is an important means of detecting the ocean. Due to the complex influence of the marine environment, there is a lot of noise and baseline drift in the signals collected by hydrophones. In order to solve this problem, this paper proposes a denoising and baseline drift removal algorithm for MEMS vector hydrophone based on whale-optimized variational mode decomposition (VMD) and correlation coefficient (CC). Firstly, the power spectrum entropy (PSE), which reflects the variation characteristics of the signal frequency is selected as the fitness function of the whale-optimization algorithm to find the parameters (K,α) of the VMD. It is easier to find the global optimal solution of the parameters by combining the whale-optimization algorithm. Then, using the VMD algorithm after obtaining the parameters, the original signal is decomposed to obtain the intrinsic mode functions (IMFs), and calculating the correlation coefficients (CCs) between the IMFs and the original signal. Finally, the CC threshold is used to remove the noise IMFs, and the rest of the useful IMFs are reconstructed to complete the denoising and baseline drift removal process of the original signals. In the simulation experiments, the algorithm proposed in this paper shows better performance by comparing conventional digital signal-processing methods and the related algorithms proposed recently. Applied in the experiments of a MEMS hydrophone, the effectiveness of the proposed algorithm is also verified. This algorithm can provide new ideas for signal denoising and baseline drift removal.
Dynamic Response of Elastomer-Based Liquid-Filled Variable Focus Lens
Authors: Wang Lihui , Ishikawa Masatoshi
Published: October 2019

Variable focus lenses are capable of dynamically varying their focal lengths. The focal length is varied by adjusting the curvature of the refractive surface and the media on both sides of the lens. The dynamic response is one of the most important criteria to determine the performance of variable focus lens. In this work, we investigated critical factors that affect the dynamic response of liquid-filled variable focus lens with a large aperture size. Based on a theoretical analysis of a circular disk representative of a deformable surface, we found that the dynamic response is significantly influenced by the diameter, thickness, and stiffness of the disk because these factors determine its first natural frequency. We also studied the dynamic response of elastomer-based liquid-filled variable focus lens prototype with different aperture sizes (20 and 30 mm) by using experiments and we found that the lens with the smaller aperture size had an excellent dynamic response.
Erratum: Cuvette-Type LSPR Sensor for Highly Sensitive Detection of Melamine in Infant Formulas. Sensors 2018, 19(18), 3839
Authors: Oh Seo Yeong , Lee Min Ji , Heo Nam Su , Kim Suji , Oh Jeong Su , Lee Yuseon , Jeon Eun Jeong , Park Tae Jung , Chun Hyang Sook , Huh Yun Suk
Published: October 2019

The authors wish to make the following erratum to this paper [...]
Dual-Polarized Fiber Laser Sensor for Photoacoustic Microscopy
Authors: Lin Xiangwei , Liang Yizhi , Jin Long , Wang Lidai
Published: October 2019

Optical resolution photoacoustic microscopy (OR-PAM) provides high-resolution, label-free and non-invasive functional imaging for broad biomedical applications. Dual-polarized fiber laser sensors have high sensitivity, low noise, a miniature size, and excellent stability; thus, they have been used in acoustic detection in OR-PAM. Here, we review recent progress in fiber-laser-based ultrasound sensors for photoacoustic microscopy, especially the dual-polarized fiber laser sensor with high sensitivity. The principle, characterization and sensitivity optimization of this type of sensor are presented. In vivo experiments demonstrate its excellent performance in the detection of photoacoustic (PA) signals in OR-PAM. This review summarizes representative applications of fiber laser sensors in OR-PAM and discusses their further improvements.
Experimental Demonstration of Surface Plasmon Polaritons Reflection and Transmission Effects
Authors: Zheng Lei , Zywietz Urs , Evlyukhin Andrey , Roth Bernhard , Overmeyer Ludger , Reinhardt Carsten
Published: October 2019

Special integrated photonic surface structures composed of a dielectric semicircle ridge and a dielectric block placed on a metal substrate are proposed for the investigation of surface plasmon polariton (SPP) reflection and transmission effects. A fabrication method called microscope projection photolithography was employed for the preparation of the structures. Leakage radiation microscopy was applied for the excitation and observation of surface plasmon polaritons (SPPs). It was observed that SPPs exhibit a remarkable decrease in intensity when impinging onto the rectangular dielectric block. Nevertheless, the transmitted wave out of the dielectric block was always observable. The propagation behavior of both the reflected waves at two boundaries (air/dielectric and dielectric/air) and the transmitted wave inside the dielectric block were demonstrated for different SPP incident conditions. The variation of the angles of reflection and transmission with respect to the incident angle was analytically and experimentally investigated. An agreement between the calculated results and the experimental results was obtained. Our findings might allow for novel applications in sensing and analytics once the structures will be functionalized.
Positive and Negative Evidence Accumulation Clustering for Sensor Fusion: An Application to Heartbeat Clustering
Authors: Márquez David G. , Félix Paulo , García Constantino A. , Tejedor Javier , Fred Ana L.N. , Otero Abraham
Published: October 2019

In this work, a new clustering algorithm especially geared towards merging data arising from multiple sensors is presented. The algorithm, called PN-EAC, is based on the ensemble clustering paradigm and it introduces the novel concept of negative evidence. PN-EAC combines both positive evidence, to gather information about the elements that should be grouped together in the final partition, and negative evidence, which has information about the elements that should not be grouped together. The algorithm has been validated in the electrocardiographic domain for heartbeat clustering, extracting positive evidence from the heartbeat morphology and negative evidence from the distances between heartbeats. The best result obtained on the MIT-BIH Arrhythmia database yielded an error of 1.44%. In the St. Petersburg Institute of Cardiological Technics 12-Lead Arrhythmia Database database (INCARTDB), an error of 0.601% was obtained when using two electrocardiogram (ECG) leads. When increasing the number of leads to 4, 6, 8, 10 and 12, the algorithm obtains better results (statistically significant) than with the previous number of leads, reaching an error of 0.338%. To the best of our knowledge, this is the first clustering algorithm that is able to process simultaneously any number of ECG leads. Our results support the use of PN-EAC to combine different sources of information and the value of the negative evidence.
Influence of Moisture Content on Electromagnetic Response of Concrete Studied Using a Homemade Apparatus
Authors: Li Zhe , Jin Zuquan , Shao Shuangshuang , Zhao Tiejun , Wang Penggang
Published: October 2019

In this study, we examined the influence of moisture content on the electromagnetic response of concrete. A novel homemade electromagnetic monitoring apparatus was developed and used to evaluate the Hall effect voltage at both ends of concrete based on our previous study of the Hall effect. We used four different concrete mix water/binder ratios: 0.30, 0.28, 0.26, and 0.24, and three conditions (relative humidity, carbonation, and water absorption) were examined in this experiment. The results show that the moisture content inside concrete influences the relative permeability of concrete. The variation in the Hall effect voltage is more influenced by carbonation than changes in relative humidity; water absorption increases the Hall effect voltage the least amongst the other examined factors. According to the experiment, a calibration system was established, and the relevant correction factors are provided.
The Effect of All-Terrain Vehicle Crash Location on Emergency Medical Services Time Intervals
Authors: Wubben Brandon M. , Denning Gerene M. , Jennissen Charles A.
Published: October 2019

Over 100,000 all-terrain vehicle (ATV)-related injuries are evaluated in U.S. emergency departments each year. In this study, we analyzed the time intervals for emergency medical services (EMS) providers responding to ATV crashes in different location types. Data from the Iowa State Trauma Registry and a statewide ATV crash/injury database was matched with Iowa EMS Registry records from 2004–2014. Ground ambulance responses to 270 ATV crashes were identified, and response characteristics and time intervals were analyzed. Off-road crashes had a longer median patient access interval (p < 0.001) and total on scene interval (p = 0.002) than roadway crashes. Crashes in remote locations had a longer median patient access interval (p < 0.001) and total on scene interval (p < 0.001), but also a longer median on scene with patient interval (p = 0.004) than crashes in accessible locations. Fifteen percent of remote patient access times were >6 min as compared to 3% of accessible crashes (p = 0.0004). There were no differences in en route to scene or en route to hospital time. Comparisons by location type showed no differences in injury severity score or number of total procedures performed. We concluded that responding EMS providers had an increased length of time to get to the patient after arriving on scene for off-road and remote ATV crashes relative to roadway and accessible location crashes, respectively.
Runoff Predicting and Variation Analysis in Upper Ganjiang Basin under Projected Climate Changes
Authors: Deng Chao , Wang Weiguang
Published: October 2019

Catchment runoff is significantly affected by climate condition changes. Predicting the runoff and analyzing its variations under future climates play a vital role in water security, water resource management, and the sustainable development of the catchment. In traditional hydrological modeling, fixed model parameters are usually used to transfer the global climate models (GCMs) to runoff, while the hydrologic model parameters may be time-varying. It is more appropriate to use the time-variant parameter for runoff modeling. This is achieved by incorporating the time-variant parameter approach into a two-parameter water balance model (TWBM) through the construction of time-variant parameter functions based on the identified catchment climate indicators. Using the Ganjiang Basin with an outlet of the Dongbei Hydrological Station as the study area, we developed time-variant parameter scenarios of the TWBM model and selected the best-performed parameter functions to predict future runoff and analyze its variations under the climate model projection of the BCC-CSM1.1(m). To synthetically assess the model performance improvements using the time-variant parameter approach, an index Δ was developed by combining the Nash–Sutcliffe efficiency, the volume error, the Box–Cox transformed root-mean-square error, and the Kling–Gupta efficiency with equivalent weight. The results show that the TWBM model with time-variant C (evapotranspiration parameter) and SC (water storage capacity of catchment), where growing and non-growing seasons are considered for C, outperformed the model with constant parameters with a Δ value of approximately 5% and 10% for the calibration and validation periods, respectively. The mean annual values of runoff predictions under the four representative concentration pathways (RCPs) exhibited a decreasing trend over the future three decades (2021–2050) when compared to the runoff simulations in the baseline period (1982–2011), where the values were about −9.9%, −19.5%, −16.6%, and −11.4% for the RCP2.6, RCP4.5, RCP6.0, and RCP8.5, respectively. The decreasing trend of future precipitation exerts impacts on runoff decline. Generally, the mean monthly changes of runoff predictions showed a decreasing trend from January to August for almost all of the RCPs, while an increasing trend existed from September to November, along with fluctuations among different RCPs. This study can provide beneficial references to comprehensively understand the impacts of climate change on runoff prediction and thus improve the regional strategy for future water resource management.
Evaluating Spatial Disparity of Access to Public Parks in Gated and Open Communities with an Improved G2SFCA Model
Authors: Zhang Jinguang , Cheng Yingyi , Wei Wei , Zhao Bing
Published: October 2019

A major concern of social equity and environmental justice is whether urban green resources are equitably distributed across the compact megacities of China. Many previous studies have evaluated the disparities in park access among various social groups, but few researchers have considered the heterogeneity of the built environment in residential communities. This study revisits an increasingly popular Gaussian-two-step floating catchment area (G2SFCA) model and mainly improves its two core parameters, the comprehensive supply indicator and variable catchment, in order to realistically evaluate park accessibility under different travel modes. We choose Nanjing city, China, as the study case in which to evaluate differences in public park access with respect to gated and open communities using our improved model. Moreover, gated communities have been further divided into three categories, which represent differences in a community’s ability to provide daily physical activities, to more deeply explore disparities in public park services. The results show that (1) the spatial accessibility of parks in Nanjing city is not evenly distributed, with communities located north of the Yangtze River having inferior park accessibility; (2) residents who live in open communities are more restricted with regard to access to parks than those in gated communities, although they experience relatively small differences under the walking mode; (3) gated communities with no internal park (“club park”) enjoy better public park services; and (4) residents living in 105 open communities and 167 gated communities without a club park can be regarded as the most vulnerable groups based on the lack of park services. The results of this study can provide a scientific basis for policy makers to target specific communities of vulnerable groups for further urban park development.
Residential Land Use Change in the Wissahickon Creek Watershed: Profitability and Sustainability?
Authors: Sorrentino John , Meenar Mahbubur , Wargo Donald
Published: October 2019

The Wissahickon Creek Watershed is one of five major watersheds in the Philadelphia metro region. The main objective of the work in this paper was to determine and compare the energy and environmental impacts of placing housing in the Watershed according to profitability and environmental sustainability criteria, respectively, in the context of increasing urbanization. Future population and employment for the Watershed have been projected by the Delaware Valley Regional Planning Commission. Housing requirements for the projected populations in each municipality were computed, and their location was influenced by the local zoning ordinances. Suitability analysis using ArcGIS 10.6 generated areas for development based alternatively on profitability and local sustainability. CommunityViz 5.2 Scenario 360 software was used to place buildings within the appropriately-zoned areas. Using Argonne National Laboratory’s Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET1 2018) software and water quality monitoring information from the Philadelphia Water Department, impacts were directly estimated. The impacts were related to effects on ecosystem functioning, ecosystem goods and services, and broad value estimated for the latter. The effects were used to indicate what might be appropriate policies to reduce the negative environmental consequences of residential development in the watershed. Unexpectedly, the environmental impacts of the profitable and sustainable scenarios were not very different. This suggests that profitability and sustainability need not be mutually exclusive.
The Potential of Open Space for Enhancing Urban Seismic Resilience: A literature Review
Authors: Koren David , Rus Katarina
Published: October 2019

For a city to perform successfully, and its citizens to feel safe and comfortable, the health of basic urban components and the overall resilience of the urban system is crucial. As the importance of the resilient urban system has been recognized in the scientific literature, many studies have been done on this topic. Therefore, to find out the gaps in the existing literature and the opportunities for further research, a new systematic literature review has been performed in three stages. Different bibliographic techniques (co-occurrence and co-citation analysis) have been applied and, in the final stage of the analysis, an in-depth study of the content of the selected papers addressing open space in relation to urban seismic resilience has been carried out. The obtained results and trends have shown a lack of research on the potential of open space for enhancing urban seismic resilience, as well as a challenge for its quantitative assessment. The ability of the affected resilient system is to achieve at least a pre-disaster performance level in an acceptable time, which can be gained, among others, by using the restorative potential of open space. Based on the synthesis of these findings the authors’ draft model of an urban system integrating the potential of open space is presented in terms of a complex network theory.
Sustainable Supply Chain Management Practices and Sustainable Performance in Hospitals: A Systematic Review and Integrative Framework
Authors: Duque-Uribe Verónica , Sarache William , Gutiérrez Elena Valentina
Published: October 2019

Hospital supply chains are responsible for several economic inefficiencies, negative environmental impacts, and social concerns. However, a lack of research on sustainable supply chain management specific to this sector is identified. Existing studies do not analyze supply chain management practices in an integrated and detailed manner, and do not consider all sustainable performance dimensions. To address these gaps, this paper presents a systematic literature review and develops a framework for identifying the supply chain management practices that may contribute to sustainable performance in hospitals. The proposed framework is composed of 12 categories of management practices, which include strategic management and leadership, supplier management, purchasing, warehousing and inventory, transportation and distribution, information and technology, energy, water, food, hospital design, waste, and customer relationship management. On the other side, performance categories include economic, environmental, and social factors. Moreover, illustrative effects of practices on performance are discussed. The novelty of this document lies in its focus on hospital settings, as well as on its comprehensiveness regarding the operationalization of practices and performance dimensions. In addition, a future research agenda is provided, which emphasizes the need for improved research generalizability, empirical validation, integrative addressing, and deeper analysis of relationships between practices and performance.
Ochratoxin A Sequentially Activates Autophagy and the Ubiquitin-Proteasome System
Authors: Akpinar Hafize Aysin , Kahraman Hilal , Yaman Ibrahim
Published: October 2019

Ochratoxin A (OTA) is a carcinogenic mycotoxin, which is produced by Aspergillus and Penicillium genera of fungi and commonly contaminates food and feed. We and others have previously shown that OTA causes sustained activation of PI3K/AKT and MAPK/ERK1-2 signaling pathways in different cell types and animal models. Given the close relationship between cellular signaling activity and protein stability, we were curious whether increased PI3K/AKT and MAPK/ERK1-2 signaling may be the result of OTA-stimulated alterations in proteolytic activity. We show that both of the major proteolytic systems, autophagy, and the ubiquitin-proteasome system (UPS), are activated upon OTA exposure in human kidney proximal tubule HK-2 and mouse embryonic fibroblast (MEF) cells. OTA stimulates transient autophagic activity at early time points of treatment but autophagic activity subsides after 6 h even in the sustained presence of OTA. Interestingly, OTA exposure also results in increased cell death in wild-type MEF cells but not in autophagy-halted Atg5-deficient cells, suggesting that autophagy exerts a pro-death effect on OTA-induced cytotoxicity. In addition, prolonged OTA exposure decreased ubiquitinated protein levels by increasing proteasomal activity. Using purified and cellular proteasomes, we observed enhanced chymotrypsin-, caspase-, and trypsin-like activities of the 26S but not the 20S proteasome in the presence of OTA. However, in the cellular context, increased proteasomal activity depended on prior induction of autophagy. Our results suggest that autophagy and subsequent UPS activation are responsible for sustained activation of PI3K/AKT and MAPK/ERK1-2 pathways through regulating the levels of critical phosphatases VHR/DUSP3, DUSP4, and PHLPP, which are known to be involved in OTA toxicity and carcinogenicity.
Decontamination of T-2 Toxin in Maize by Modified Montmorillonite Clay
Authors: Olopade Bunmi K. , Oranusi Solomon U. , Nwinyi Obinna C. , Lawal Isiaka A. , Gbashi Sefater , Njobeh Patrick B.
Published: October 2019

Montmorillonite clay has a wide range of applications, one of which includes the binding of mycotoxins in foods and feeds through adsorption. T-2 toxin, produced by some Fusarium, Myrothecium, and Stachybotrys species, causes dystrophy in the brain, heart, and kidney. Various formulations that include lemongrass essential oil-modified montmorillonite clay (LGEO-MMT), lemongrass powder (LGP), montmorillonite clay washed with 1 mM NaCl (Na-MMT), montmorillonite clay (MMT), and lemongrass powder mixed with montmorillonite clay (LGP-MMT) were applied to maize at concentrations of 8% and 12% and stored for a period of one month at 30 °C. Unmodified montmorillonite clay and LGP served as the negative controls alongside untreated maize. Fourier Transform Infrared (FTIR) spectra of the various treatments showed the major functional groups as Si-O and -OH. All treatment formulations were effective in the decontamination of T-2 toxin in maize. Accordingly, it was revealed that the inclusion of Na-MMT in maize at a concentration of 8% was most effective in decontaminating T-2 toxin by 66% in maize followed by LGP-MMT at 12% inclusion level recording a 56% decontamination of T-2 toxin in maize (p = 0.05). Montmorillonite clay can be effectively modified with plant extracts for the decontamination of T-2 toxin.
Salience Models: A Computational Cognitive Neuroscience Review
Authors: Krasovskaya Sofia , MacInnes W. Joseph
Published: October 2019

The seminal model by Laurent Itti and Cristoph Koch demonstrated that we can compute the entire flow of visual processing from input to resulting fixations. Despite many replications and follow-ups, few have matched the impact of the original model—so what made this model so groundbreaking? We have selected five key contributions that distinguish the original salience model by Itti and Koch; namely, its contribution to our theoretical, neural, and computational understanding of visual processing, as well as the spatial and temporal predictions for fixation distributions. During the last 20 years, advances in the field have brought up various techniques and approaches to salience modelling, many of which tried to improve or add to the initial Itti and Koch model. One of the most recent trends has been to adopt the computational power of deep learning neural networks; however, this has also shifted their primary focus to spatial classification. We present a review of recent approaches to modelling salience, starting from direct variations of the Itti and Koch salience model to sophisticated deep-learning architectures, and discuss the models from the point of view of their contribution to computational cognitive neuroscience.
Flood-Prone Area Assessment Using GIS-Based Multi-Criteria Analysis: A Case Study in Davao Oriental, Philippines
Authors: Cabrera Jonathan Salar , Lee Han Soo
Published: October 2019

Flooding is one of the major destructive natural disasters in Davao Oriental, Philippines, and results primarily from a high incidence of typhoons and heavy rainfalls. The main objective of this study was to identify flood-prone risk areas by mapping them based on the integration of multiple indicators, including rainfall, slope, elevation, drainage density, soil type, distance to the main channel and population density. For this purpose, a GIS-based flood risk spatial assessment was conducted by using analytic hierarchy process (AHP), weights by rank (WR) and ratio weighting (RW) frameworks to determine the relative importance of each indicator against another in the province of Davao Oriental. The resulting flood-prone areas by the three methods are validated by comparing with the estimated flood map based on ground truthing points from a field survey. The comparison results show that AHP is the most appropriate method among them to assess flood hazard. The result of the AHP flood risk map shows that 95.99% (5451.27 km2) of Davao Oriental is under low and moderate flood risk. The high and very high flood risk area covers approximately 3.39% (192.52 km2) of the province, primarily in the coastal areas. Thirty-one out of the one hundred eighty-three (31/183) barangays (towns) are at a high to very high risk of flooding at current climate, calling for the immediate attention of decision-makers to develop mitigation strategies for the future occurrence of flooding in Davao Oriental.
Two Dimensional Model for Backwater Geomorphology: Darby Creek, PA
Authors: Hosseiny Hossein , Smith Virginia
Published: October 2019

Predicting morphological alterations in backwater zones has substantial merit as it potentially influences the life of millions of people by the change in flood dynamics and land topography. While there is no two-dimensional river model available for predicting morphological alterations in backwater zones, there is an absolute need for such models. This study presents an integrated iterative two-dimensional fluvial morphological model to quantify spatio-temporal fluvial morphological alterations in normal flow to backwater conditions. The integrated model works through the following steps iteratively to derive geomorphic change: (1) iRIC model is used to generate a 2D normal water surface; (2) a 1D water surface is developed for the backwater; (3) the normal and backwater surfaces are integrated; (4) an analytical 2D model is established to estimate shear stresses and morphological alterations in the normal, transitional, and backwater zones. The integrated model generates a new digital elevation model based on the estimated erosion and deposition. The resultant topography then serves as the starting point for the next iteration of flow, ultimately modeling geomorphic changes through time. This model was tested on Darby Creek in Metro-Philadelphia, one of the most flood-prone urban areas in the US and the largest freshwater marsh in Pennsylvania.
Exploring the Effects of Alternative Water Demand Management Strategies Using an Agent-Based Model
Authors: Koutiva Ifigeneia , Makropoulos Christos
Published: October 2019

Integrated urban water management calls for tools that can analyze and simulate the complete cycle including the physical, technical, and social dimensions. Scientific advances created simulation tools able to simulate the urban water cycle as realistically as possible. However, even these tools cannot effectively simulate the social component and quantify how behaviors are shaped by external stress factors, such as climate and policies. In this work, an agent-based modeling tool, urban water agents’ behavior (UWAB) is used to simulate the water demand behavior of households and how it is influenced by water demand management strategies and drought conditions. UWAB was applied in Athens, Greece to explore the effect of different water demand management strategies to the reliability of the Athens hydrosystem. The results illustrate the usability of UWAB to support decision makers in identifying how “strict” water demand management measures are needed and when and for how long to deploy them in order to alleviate potential water supply issues.
A Method for Fast Evaluation of Potential Consequences of Dam Breach
Authors: Ge Wei , Jiao Yutie , Sun Heqiang , Li Zongkun , Zhang Hexiang , Zheng Yan , Guo Xinyan , Zhang Zhaosheng , van Gelder P.H.A.J.M.
Published: October 2019

Dam breach has catastrophic consequences for human lives and economy. In previous studies, empirical models are often, to a limited extent, due to the inadequacy of historical dam breach events. Physical models, which focus on simulating human behavior during floods, are not suitable for fast analysis of a large number of dams due to the complexities of many key parameters. Therefore, this paper proposes a method for fast evaluation of potential consequences of dam breach. Eight main indices, i.e., capacity of reservoir (CR), dam height (HD), population at risk (PR), economy at risk (ER), understanding of dam breach (UB), industry type (TI), warning time (TW), and building vulnerability (VB), are selected to establish an evaluation index system. A catastrophe evaluation method is introduced to establish an evaluation model for potential consequences of dam breach based on the indices which are divided into five grades according to the relevant standards and guidelines. Validation of the method by twelve historical dam breach events shows a good accuracy. The method is applied to evaluate potential consequences of dam breach of Jiangang Reservoir in Henan Province, China. It is estimated that loss of life in the worst scenario is between that of Hengjiang Reservoir and that of Shimantan Reservoir dam breach, of which fatalities are 941 and 2717, respectively, showing that risk management measures should be taken to reduce the risk of potential loss of life.
A Rapid Assessment Method to Identify Potential Groundwater Flooding Hotspots as Sea Levels Rise in Coastal Cities
Authors: Plane Ellen , Hill Kristina , May Christine
Published: October 2019

Sea level rise (SLR) will cause shallow unconfined coastal aquifers to rise. Rising groundwater can emerge as surface flooding and impact buried infrastructure, soil behavior, human health, and nearshore ecosystems. Higher groundwater can also reduce infiltration rates for stormwater, adding to surface flooding problems. Levees and seawalls may not prevent these impacts. Pumping may accelerate land subsidence rates, thereby exacerbating flooding problems associated with SLR. Public agencies at all jurisdiction levels will need information regarding where groundwater impacts are likely to occur for development and infrastructure planning, as extreme precipitation events combine with SLR to drive more frequent flooding. We used empirical depth-to-water data and a digital elevation model of the San Francisco Bay Area to construct an interpolated surface of estimated minimum depth-to-water for 489 square kilometers along the San Francisco Bay shoreline. This rapid assessment approach identified key locations where more rigorous data collection and dynamic modeling is needed to identify risks and prevent impacts to health, buildings, and infrastructure, and develop adaptation strategies for SLR.
Well Rate and Placement for Optimal Groundwater Remediation Design with A Surrogate Model
Authors: Sbai Mohammed Adil
Published: October 2019

A new surrogate-assisted optimization formulation for groundwater remediation design was developed. A stationary Eulerian travel time model was used in lieu of a conservative solute transport model. The decision variables of the management model are well locations and their flow rates. The objective function adjusts the residence time distribution between all pairs of injection-production wells in the remediation system. This goal is achieved by using the Lorenz coefficient as an effective metric to rank the relative efficiency of many remediation policies. A discrete adjoint solver was developed to provide the sensitivity of the objective function with respect to changes in decision variables. The quality management model was checked with simple solutions and then applied to hypothetical two- and three-dimensional test problems. The performance of the simulation-optimization approach was evaluated by comparing the initial and optimal remediation designs using an advective-dispersive solute transport simulator. This study shows that optimal designs simultaneously delay solute transport breakthrough at pumping wells and improve the sweep efficiency leading to smaller cleanup times. Well placement optimization in heterogeneous porous media was found to be more important than well rate optimization. Additionally, optimal designs based on two-dimensional models were found to be more optimistic suggesting a direct use of three-dimensional models in a simulation-optimization framework. The computational budget was drastically reduced because the proposed surrogate-based quality management model is generally cheaper than one single solute transport simulation. The introduced model could be used as a fast, but first-order, approximation method to estimate pump-and-treat capital remediation costs. The results show that physically based low-fidelity surrogate models are promising computational approaches to harness the power of quality management models for complex applications with practical relevance.
Unpacking Barriers to Socially Inclusive Weather Index Insurance: Towards a Framework for Inclusion
Authors: Aheeyar Mohamed , de Silva Sanjiv , Senaratna-Sellamuttu Sonali , Arulingam Indika
Published: October 2019

Floods account for a majority of disasters, especially in South Asia, where they affect 27 million people annually, causing economic losses of over US$1 billion. Climate change threatens to exacerbate these risks. Risk transfer mechanisms, such as weather index insurance (WII) may help buffer farmers against these hazards. However, WII programs struggle to attract the clients most in need of protection, including marginalized women and men. This risks re-enforcing existing inequalities and missing opportunities to promote pro-poor and gender-sensitive development. Key questions, therefore, include what factors constrain access to WIIs amongst heterogeneous communities, and how these can be addressed. This paper contributes to that end through primary data from two WII case studies (one in India, the other in Bangladesh) that identify contextual socio-economic and structural barriers to accessing WII, and strategies to overcome these. More significantly, this paper synthesizes the case study findings and those from a review of the literature on other WII initiatives into a framework to promote a systematic approach to address these challenges: an important step forward in moving from problem analysis to remedial action. The framework highlights actions across WII product design, implementation and post-implementation, to minimize risks of social exclusion in future WII schemes.
COMPARATIVE ANALYSIS OF VARIOUS DIAGRAMS OF CONCRETE DEFORMATION ACCORDING TO THE CRITERION OF ENERGY CONSUMPTION FOR DEFORMATION AND DESTRUCTION
Authors: Радайкин Олег , Radaikin Oleg
Published: October 2019

From the point of view of strength calculations, it is convenient to describe concrete work under load by deformation diagrams "σ-ε" under uniaxial tension and compression. The result of the calculation depends on the shape of the corresponding diagram, the mathematical expression on which it is based and other factors. According to the author, the universal criterion for assessing the resistance of concrete to force impact is the energy consumption for deformation and destruction of the material. This criterion is calculated through a definite integral of the function σ=f (ε). Ten diagrams of concrete deformation under compression and four under tension from available and original literature sources are considered using this integral. Some qualitative and quantitative regularities are established. The following conclusion is made: compression diagrams can be recommended for further improvement of the nonlinear deformation mode: three-line, curvilinear; the stretching diagrams and are the most suitable for engineering calculations when using the considered model in its modern form.
La Minería en el Perú de hoy
Authors: Manrique Oroza Pablo I. , Arce Larrea Glenn
Published: October 2019

El artículo busca resaltar el importante rol que ha desarrollado y desarrolla la actividad minera en el Perú, en los últimos años, con una breve reseña de la importancia de esta actividad a lo largo de la historia de nuestro país desde épocas pre colombinas.