bluuebunny/crossref_metadata_2025 huggingface dataset:
Partial Discharge Ultrasound Detection Using the Sagnac Interferometer System
Authors: Wang Yu , Li Xiaomin , Gao Yan , Zhang Hongjuan , Wang Dong , Jin Baoquan
Published: May 2018

Partial discharge detection is crucial for electrical cable safety evaluation. The ultrasonic signals frequently generated in the partial discharge process contains important characteristic information. However, traditional ultrasonic transducers are easily subject to strong electromagnetic interference in environments with high voltages and strong magnetic fields. In order to overcome this problem, an optical fiber Sagnac interferometer system is proposed for partial discharge ultrasound detection. Optical fiber sensing and time-frequency analysis of the ultrasonic signals excited by the piezoelectric ultrasonic transducer is realized for the first time. The effective frequency band of the Sagnac interferometer system was up to 175 kHz with the help of a designed 10 kV partial discharge simulator device. Using the cumulative histogram method, the characteristic ultrasonic frequency band of the partial discharges was between 28.9 kHz and 57.6 kHz for this optical fiber partial discharge detection system. This new ultrasound sensor can be used as an ideal ultrasonic source for the intrinsically safe detection of partial discharges in an explosive environment.
Do Monetary Incentives Influence Users’ Behavior in Participatory Sensing?
Authors: Khoi Ngo Manh , Casteleyn Sven , Moradi M. Mehdi , Pebesma Edzer
Published: May 2018

Participatory sensing combines the powerful sensing capabilities of current mobile devices with the mobility and intelligence of human beings, and as such has to potential to collect various types of information at a high spatial and temporal resolution. Success, however, entirely relies on the willingness and motivation of the users to carry out sensing tasks, and thus it is essential to incentivize the users’ active participation. In this article, we first present an open, generic participatory sensing framework (Citizense) which aims to make participatory sensing more accessible, flexible and transparent. Within the context of this framework we adopt three monetary incentive mechanisms which prioritize the fairness for the users while maintaining their simplicity and portability: fixed micro-payment, variable micro-payment and lottery. This incentive-enabled framework is then deployed on a large scale, real-world case study, where 230 participants were exposed to 44 different sensing campaigns. By randomly distributing incentive mechanisms among participants and a subset of campaigns, we study the behaviors of the overall population as well as the behaviors of different subgroups divided by demographic information with respect to the various incentive mechanisms. As a result of our study, we can conclude that (1) in general, monetary incentives work to improve participation rate; (2) for the overall population, a general descending order in terms of effectiveness of the incentive mechanisms can be established: fixed micro-payment first, then lottery-style payout and finally variable micro-payment. These two conclusions hold for all the demographic subgroups, even though different different internal distances between the incentive mechanisms are observed for different subgroups. Finally, a negative correlation between age and participation rate was found: older participants contribute less compared to their younger peers.
A Flexible Interdigital Electrode Used in Skin Penetration Promotion and Evaluation with Electroporation and Reverse Iontophoresis Synergistically
Authors: Zhao Rongjian , Wang Chenshuo , Lu Fei , Du Lidong , Fang Zhen , Guo Xiuhua , Liu Jen-Tsai , Chen Ching-Jung , Zhao Zhan
Published: May 2018

Skin penetration is related to efficiencies of drug delivery or ISF extraction. Normally, the macro-electrode is employed in skin permeability promotion and evaluation, which has the disadvantages of easily causing skin damage when using electroporation or reverse iontophoresis by alone; furthermore, it has large measurement error, low sensitivity, and difficulty in integration. To resolve these issues, this paper presents a flexible interdigital microelectrode for evaluating skin penetration by sensing impedance and a method of synergistical combination of electroporation and reverse iontophoresis to promote skin penetration. First, a flexible interdigital microelectrode was designed with a minimal configuration circuit of electroporation and reverse iontophoresis for future wearable application. Due to the variation of the skin impedance correlated with many factors, relative changes of it were recorded at the end of supply, different voltage, or constant current, times, and duration. It is found that the better results can be obtained by using electroporation for 5 min then reverse iontophoresis for 12 min. By synergistically using electroporation and reverse iontophoresis, the penetration of skin is promoted. The results tested in vivo suggest that the developed microelectrode can be applied to evaluate and promote the skin penetration and the designed method promises to leave the skin without damage. The electrode and the method may be beneficial for designing noninvasive glucose sensors.
Mixed Incoherent Far-Field and Near-Field Source Localization under Uniform Circular Array
Authors: Su Xiaolong , Liu Zhen , Chen Xin , Li Xiang
Published: May 2018

A high-accuracy algorithm is presented for the localization of mixed incoherent near-field and far-field narrow-band sources under uniform circular array (UCA). Herein, considering that it is difficult to classify the mixed sources, we first decouple mixed sources’ angles and ranges by calculating centro-symmetric sensors’ phase differences. Then, as the phase differences including only sources’ angles can be transformed as indefinite equations, each source’s azimuth angle and elevation angle are obtained by performing the least squares method. After that, on the basis of the estimated angles of the mixed sources, one-dimensional (1-D) multiple signal classification (MUSIC) method and corresponding spatial spectrum are utilized to identify the mixed sources and estimate the ranges of the near-field sources. Finally, simulation and comparison results verify the superior performance of our proposed algorithm.
Impact Assessment of GNSS Spoofing Attacks on INS/GNSS Integrated Navigation System
Authors: Liu Yang , Li Sihai , Fu Qiangwen , Liu Zhenbo
Published: May 2018

In the face of emerging Global Navigation Satellite System (GNSS) spoofing attacks, there is a need to give a comprehensive analysis on how the inertial navigation system (INS)/GNSS integrated navigation system responds to different kinds of spoofing attacks. A better understanding of the integrated navigation system’s behavior with spoofed GNSS measurements gives us valuable clues to develop effective spoofing defenses. This paper focuses on an impact assessment of GNSS spoofing attacks on the integrated navigation system Kalman filter’s error covariance, innovation sequence and inertial sensor bias estimation. A simple and straightforward measurement-level trajectory spoofing simulation framework is presented, serving as the basis for an impact assessment of both unsynchronized and synchronized spoofing attacks. Recommendations are given for spoofing detection and mitigation based on our findings in the impact assessment process.
Liquefied Petroleum Gas Monitoring System Based on Polystyrene Coated Long Period Grating
Authors: Esposito Flavio , Zotti Aldobenedetto , Palumbo Giovanna , Zuppolini Simona , Consales Marco , Cutolo Antonello , Borriello Anna , Campopiano Stefania , Zarrelli Mauro , Iadicicco Agostino
Published: May 2018

In this work, we report the in-field demonstration of a liquefied petroleum gas monitoring system based on optical fiber technology. Long-period grating coated with a thin layer of atactic polystyrene (aPS) was employed as a gas sensor, and an array comprising two different fiber Bragg gratings was set for the monitoring of environmental conditions such as temperature and humidity. A custom package was developed for the sensors, ensuring their suitable installation and operation in harsh conditions. The developed system was installed in a real railway location scenario (i.e., a southern Italian operative railway tunnel), and tests were performed to validate the system performances in operational mode. Daytime normal working operations of the railway line and controlled gas expositions, at very low concentrations, were the searched realistic conditions for an out-of-lab validation of the developed system. Encouraging results were obtained with a precise indication of the gas concentration and external conditioning of the sensor.
Evaluating Post-Earthquake Building Safety Using Economical MEMS Seismometers
Authors: Hsu Ting-Yu , Yin Ren-Cheng , Wu Yih-Min
Published: May 2018

The earthquake early warning (EEW)-research group at National Taiwan University has been developing a microelectromechanical system-based accelerometer called “P-Alert”, designed for issuing EEWs. The main advantage of P-Alert is that it is a relatively economical seismometer. However, because of the expensive nature of commercial hardware for structural health monitoring (SHM) systems, the application of SHM to buildings remains limited. To determine the performance of P-Alert for evaluating post-earthquake building safety, we conducted a series of steel-frame shaking table tests with incremental damage. We used the fragility curves of different damage levels and the interstory drift ratios (calculated by the measured acceleration of each story using double integration and a filter) to gauge the potential damage levels. We concluded that the acceptable detection of damage for an entire building is possible. With improvements to the synchronization of the P-Alert sensors, we also anticipate a damage localization feature for the stories of a building.
A Microwave Method for Dielectric Characterization Measurement of Small Liquids Using a Metamaterial-Based Sensor
Authors: Liu Weina , Sun Haoran , Xu Lei
Published: May 2018

We present a microwave method for the dielectric characterization of small liquids based on a metamaterial-based sensor The proposed sensor consists of a micro-strip line and a double split-ring resonator (SRR). A large electric field is observed on the two splits of the double SRRs at the resonance frequency (1.9 GHz). The dielectric property data of the samples under test (SUTs) were obtained with two measurements. One is with the sensor loaded with the reference liquid (REF) and the other is with the sensor loaded with the SUTs. Additionally, the principle of extracting permittivity from measured changes of resonance characteristics changes of the sensor loaded with REF and SUTs is given. Some measurements were carried out at 1.9 GHz, and the calculated results of methanol–water mixtures with different molar fractions agree well with the time-domain reflectometry method. Moreover, the proposed sensor is compact and highly sensitive for use of sub-wavelength resonance. In comparison with literature data, relative errors are less than 3% for the real parts and 2% for the imaginary parts of complex permittivity.
Fluorescent Nanobiosensors for Sensing Glucose
Authors: Chen Longyi , Hwang Eugene , Zhang Jin
Published: May 2018

Glucose sensing in diabetes diagnosis and therapy is of great importance due to the prevalence of diabetes in the world. Furthermore, glucose sensing is also critical in the food and drug industries. Sensing glucose has been accomplished through various strategies, such as electrochemical or optical methods. Novel transducers made with nanomaterials that integrate fluorescent techniques have allowed for the development of advanced glucose sensors with superior sensitivity and convenience. In this review, glucose sensing by fluorescent nanobiosensor systems is discussed. Firstly, typical fluorescence emitting/interacting nanomaterials utilized in various glucose assays are discussed. Secondly, strategies for integrating fluorescent nanomaterials and biological sensing elements are reviewed and discussed. In summary, this review highlights the applicability of fluorescent nanomaterials, which makes them ideal for glucose sensing. Insight on the future direction of fluorescent nanobiosensor systems is also provided.
Developing a Mixed Neural Network Approach to Forecast the Residential Electricity Consumption Based on Sensor Recorded Data
Authors: Oprea Simona-Vasilica , Pîrjan Alexandru , Căruțașu George , Petroșanu Dana-Mihaela , Bâra Adela , Stănică Justina-Lavinia , Coculescu Cristina
Published: May 2018

In this paper, we report a study having as a main goal the obtaining of a method that can provide an accurate forecast of the residential electricity consumption, refining it up to the appliance level, using sensor recorded data, for residential smart homes complexes that use renewable energy sources as a part of their consumed electricity, overcoming the limitations of not having available historical meteorological data and the unwillingness of the contractor to acquire such data periodically in the future accurate short-term forecasts from a specialized institute due to the implied costs. In this purpose, we have developed a mixed artificial neural network (ANN) approach using both non-linear autoregressive with exogenous input (NARX) ANNs and function fitting neural networks (FITNETs). We have used a large dataset containing detailed electricity consumption data recorded by sensors, monitoring a series of individual appliances, while in the NARX case we have also used timestamps datasets as exogenous variables. After having developed and validated the forecasting method, we have compiled it in view of incorporating it into a cloud solution, being delivered to the contractor that can provide it as a service for a monthly fee to both the operators and residential consumers.
Least Squares Neural Network-Based Wireless E-Nose System Using an SnO2 Sensor Array
Authors: Shahid Areej , Choi Jong-Hyeok , Rana Abu ul Hassan Sarwar , Kim Hyun-Seok
Published: May 2018

Over the last few decades, the development of the electronic nose (E-nose) for detection and quantification of dangerous and odorless gases, such as methane (CH4) and carbon monoxide (CO), using an array of SnO2 gas sensors has attracted considerable attention. This paper addresses sensor cross sensitivity by developing a classifier and estimator using an artificial neural network (ANN) and least squares regression (LSR), respectively. Initially, the ANN was implemented using a feedforward pattern recognition algorithm to learn the collective behavior of an array as the signature of a particular gas. In the second phase, the classified gas was quantified by minimizing the mean square error using LSR. The combined approach produced 98.7% recognition probability, with 95.5 and 94.4% estimated gas concentration accuracies for CH4 and CO, respectively. The classifier and estimator parameters were deployed in a remote microcontroller for the actualization of a wireless E-nose system.
Active Sensor for Microwave Tissue Imaging with Bias-Switched Arrays
Authors: Foroutan Farzad , Nikolova Natalia K.
Published: May 2018

A prototype of a bias-switched active sensor was developed and measured to establish the achievable dynamic range in a new generation of active arrays for microwave tissue imaging. The sensor integrates a printed slot antenna, a low-noise amplifier (LNA) and an active mixer in a single unit, which is sufficiently small to enable inter-sensor separation distance as small as 12 mm. The sensor’s input covers the bandwidth from 3 GHz to 7.5 GHz. Its output intermediate frequency (IF) is 30 MHz. The sensor is controlled by a simple bias-switching circuit, which switches ON and OFF the bias of the LNA and the mixer simultaneously. It was demonstrated experimentally that the dynamic range of the sensor, as determined by its ON and OFF states, is 109 dB and 118 dB at resolution bandwidths of 1 kHz and 100 Hz, respectively.
Centrifugal Deposited Au-Pd Core-Shell Nanoparticle Film for Room-Temperature Optical Detection of Hydrogen Gas
Authors: Song Han , Luo Zhijie , Liu Mingyao , Zhang Gang , Peng Wang , Wang Boyi , Zhu Yong
Published: May 2018

In the present work, centrifugal deposited Au-Pd core-shell nanoparticle (NP) film was proposed for the room-temperature optical detection of hydrogen gas. The size dimension of 44, 48, 54, and 62 nm Au-Pd core-shell nanocubes with 40 nm Au core were synthesized following a solution-based seed-mediated growth method. Compared to a pure Pd NP, this core-shell structure with an inert Au core could decrease the H diffusion length in the Pd shell. Through a modified centrifugal deposition process, continues film samples with different core-shell NPs were deposited on 10 mm diameter quartz substrates. Under various hydrogen concentration conditions, the optical response properties of these samples were characterized by an intensity-based optical fiber bundle sensor. Experimental results show that the continues film that was composed of 62 nm Au-Pd core-shell NPs has achieved a stable and repeatable reflectance response with low zero drift in the range of 4 to 0.1% hydrogen after a stress relaxation mechanism at first few loading/unloading cycles. Because of the short H diffusion length due to the thinner Pd shell, the film sample composed of 44 nm Au-Pd NPs has achieved a dramatically decreased response/recovery time to 4 s/30 s. The experiments present the promising prospect of this simple method to fabricate optical hydrogen sensors with controllable high sensitivity and response rate at low cost.
Spatially Correlated Sparse MIMO Channel Path Delay Estimation in Scattering Environments Based on Signal Subspace Tracking
Authors: Mohydeen Ali , Chargé Pascal , Wang Yide , Bazzi Oussama , Ding Yuehua
Published: May 2018

A parametric scheme for spatially correlated sparse multiple-input multiple-output (MIMO) channel path delay estimation in scattering environments is presented in this paper. In MIMO outdoor communication scenarios, channel impulse responses (CIRs) of different transmit–receive antenna pairs are often supposed to be sparse due to a few significant scatterers, and share a common sparse pattern, such that path delays are assumed to be equal for every transmit–receive antenna pair. In some existing works, an exact common support condition is exploited, where the path delays are considered equal for every transmit–receive antenna pair, meanwhile ignoring the influence of scattering. A more realistic channel model is proposed in this paper, where due to scatterers in the environment, the received signals are modeled as clusters of multi-rays around a nominal or mean time delay at different antenna elements, resulting in a non-strictly exact common support phenomenon. A method for estimating the channel mean path delays is then derived based on the subspace approach, and the tracking of the effective dimension of the signal subspace that changes due to the wireless environment. The proposed method shows an improved channel mean path delays estimation performance in comparison with the conventional estimation methods.
Dynamics in the Field of Museums: Contemporary Challenges for Polish Museologists
Authors: Nieroba Elżbieta
Published: May 2018

The aim of this text is to present and analyze the attitudes of Polish museologists towards the changes currently taking place in the field of museums. More specifically, it will focus on their opinions regarding the evolution of museums—from the traditional model, based on symbolic violence, to the contemporary model, which accents the subjectivity of the audience. Its conclusions, based on analyses of 26 qualitative interviews with employees of Polish museums, are as follows: the organizational changes taking place in Polish museums do not relieve museologists from bureaucratic work; the collections in museums distinguish them from other institutions of culture; there is a struggle for symbolic advantage among actors in the field of museology; museologists do not know their audience well. The interviews also revealed that the assumptions of the New Museology have less impact on practice than is suggested in literature, and that everyday museology combines elements of the ‘old’ and ‘new’ philosophies.
Dynamics of Volunteering and Life Satisfaction in Midlife and Old Age: Findings from 12 European Countries
Authors: Hansen Thomas , Aartsen Marja , Slagsvold Britt , Deindl Christian
Published: May 2018

A growing literature shows that doing voluntary work not only helps the wider community but can also improve one’s own well-being. To date, however, few studies have examined the relationship between volunteering and well-being in non-US and especially in comparative data. We study this relationship using two waves of data of 18,559 individuals aged 50 and above from 12 European countries. We analyze life satisfaction impacts of change and stability in volunteering status and in the intensity (frequency) of volunteering, and explore whether these impacts differ according to life stage (age, employment status) and across countries with different norms and supports for voluntarism. Findings show that net life satisfaction is higher among longer-term, recent, and former volunteers than among stable (long-term) non-volunteers. There are no significant life satisfaction differences between the three groups with volunteer experience. Equally, similar levels of life satisfaction are observed among people who have increased and decreased their frequency of volunteering. It thus seems to be the experience and not the dynamics (i.e., change or persistence) of volunteering that is associated with well-being. Findings further suggest life course variation in the association between volunteering and well-being, as the relationship is stronger for older and long-term non-employed (mostly retired) individuals than for their middle-aged and working counterparts. The relationship is also stronger in countries where volunteering is less common and less institutionally supported.
Experimental Analysis of the Thermal Performance of a Sunspace Attached to a House with a Central Air Conditioning System
Authors: Ma Qingsong , Fukuda Hiroatsu , Lee Myonghyang , Kobatake Takumi , Kuma Yuko , Ozaki Akihito , Wei Xindong
Published: May 2018

In this paper, the thermal performance of a sunspace attached to a house with a central air conditioning system was experimentally investigated. The house with a south-facing sunspace is located in Miyazaki, Japan, where heating is required in winter. In order to reduce the heating energy in winter, the hot air from the attached sunspace is sent to the central air conditioning room, from where it is then distributed and stored throughout the house by way of air circulation. Only when the temperature in the sunspace exceeds 24 °C is the hot air in the sunspace sent to the central air conditioning room. The air circulation between the attached sunspace and central air conditioning room is 500 m3/h. The temperature of the attached sunspace and each room were measured. The results showed that a house with a sunspace can save about 12.2% of energy compared to a house without a sunspace.
Conservation Agriculture for Environmental Sustainability in A Semiarid Agroecological Zone under Climate Change Scenarios
Authors: Hong Zhang , Mkonda Msafiri Y. , He Xinhua
Published: May 2018

Using the Mann–Kendall Test to analyze data from a survey of 400 farmers, this study compared the rate of adoption of conservation agriculture (CA) in two contrasting villages of Mnyakongo and Ugogoni locating in the Kongwa District, a semi-arid zone in central Tanzania. Results exhibited that the level of CA adoption was <10% of the total households. The trend of CA adoption was determined at the coefficient of R2 = 0.95, 0.90, 0.68 and 0.57 for mulching, crop rotation, agroforestry and little tillage, respectively. Despite little tillage and crop rotation having high acreage under CA, the rate of mulching adoption was significantly higher than that of others. Furthermore, there were significant correlations between the CA adoption and crop yields or environmental sustainability (p < 0.05). Maize, sorghum and millet yields were significantly greater under CA (1.7 t ha−1) than no-CA (0.7 t ha−1). Particularly, maize yields were increased from 1.3 to 2.3 t ha−1 from 2000 to 2015 under CA when it was intercropped with legumes. The majority farmers (>70%) asserted that CA had optimized their yields for both food and economic incentives. Thus, this study recommends the adoption of CA in the semi-arid agro-ecological zones.
Security-Constrained Unit Commitment Considering Differentiated Regional Air Pollutant Intensity
Authors: Guo Danyang , Yu Jilai , Ban Mingfei
Published: May 2018

Conventional environmental-economic power dispatch methods constrain the total amount of emissions of power plants, and they succeed in reducing emissions from the power sector. However, they fail to address the mismatch between emission reductions and the resulting changes in regional air quality. This paper proposes an ecology- and security-constrained unit commitment (Eco-SCUC) model considering the differentiated impacts of generation-associated emissions on regional air quality. A Gaussian puff dispersion model is applied to capture the temporal-spatial transport of air pollutants. Additionally, an air pollutant intensity (API) index is defined for assessing the impacts of emissions on the air quality in regions with differentiated atmospheric environmental capacities. Then the API constraints are formulated based on air quality forecast and included in SCUC model. Moreover, the stochastic optimization is employed to accommodate wind power uncertainty, and the Benders decomposition technique is used to solve the formulated mixed-integer quadratic programming (MIQP) problem. Case studies demonstrate that the Eco-SCUC can cost-effectively improve air quality for densely-populated regions via shifting generation among units and can significantly reduce the person-hours exposed to severe air pollution. Furthermore, the benefits of wind power for air quality control are investigated.
Towards Place-Based Research to Support Social–Ecological Stewardship
Authors: Cockburn Jessica , Cundill Georgina , Shackleton Sheona , Rouget Mathieu
Published: May 2018

Concerns about ecological degradation and social inequalities have prompted increasing calls for stewardship in the social–ecological systems and sustainability science literature. However, how can the ideals of stewardship be realised in practice? The links between the theory and practice of stewardship are under-developed, and research to support place-based stewardship practice is limited. We therefore bring together complementary perspectives to guide research on place-based stewardship practice in the context of multifunctional landscapes. We unpack and synthesise literature on stewardship, landscapes, and collaboration for natural resource management, and highlight the ways in which the pathways approach can deepen research on collaboration and stewardship practice. We propose landscapes as a suitable level of analysis and action for stewardship. Since all landscapes are multifunctional, we argue that collaboration among multiple stakeholders is a necessary focus of such research. Our analysis reveals that existing theory on collaboration could be deepened by further research into the agency of individual human actors, the complex social–relational dynamics among actors, and the situatedness of actors within the social–ecological context. These factors mediate collaborative processes, and a better understanding of them is needed to support place-based stewardship practice. To this end, the pathways approach offers a waymark to advance research on collaboration, particularly in the complex, contested social–ecological systems that tend to characterize multifunctional landscapes.
The Role of Pseudomonas aeruginosa ExoY in an Acute Mouse Lung Infection Model
Authors: Kloth Christina , Schirmer Bastian , Munder Antje , Stelzer Tane , Rothschuh Justin , Seifert Roland
Published: May 2018

The effector protein Exotoxin Y (ExoY) produced by Pseudomonas aeruginosa is injected via the type III secretion system (T3SS) into host cells. ExoY acts as nucleotidyl cyclase promoting the intracellular accumulation of cyclic nucleotides. To what extent nucleotidyl cyclase activity contributes to the pathogenicity of ExoY and which mechanisms participate in the manifestation of lung infection is still unclear. Here, we used an acute airway infection model in mice to address the role of ExoY in lung infection. In infected lungs, a dose-dependent phenotype of infection with bacteria-expressing ExoY was mirrored by haemorrhage, formation of interstitial oedema in alveolar septa, and infiltration of the perivascular space with erythrocytes and neutrophilic granulocytes. Analyses of the infection process on the cellular and organismal level comparing infections with Pseudomonas aeruginosa mutants expressing either nucleotidyl cyclase-active or -inactive ExoY revealed differential cytokine secretion, increased prevalence of apoptosis, and a break of lung barrier integrity in mice infected with cyclase-active ExoY. Notably, of all measured cyclic nucleotides, only the increase of cyclic UMP in infected mouse lungs coincides temporally with the observed early pathologic changes. In summary, our results suggest that the nucleotidyl cyclase activity of ExoY can contribute to P. aeruginosa acute pathogenicity.
Complete Nucleotide Sequence Analysis of a Novel Bacillus subtilis-Infecting Bacteriophage BSP10 and Its Effect on Poly-Gamma-Glutamic Acid Degradation
Authors: Ghosh Kuntal , Senevirathne Amal , Kang Hai Seong , Hyun Woo Bin , Kim Ji Eun , Kim Kwang-Pyo
Published: May 2018

While the harmful effects of lactic acid bacterial bacteriophages in the dairy industry are well-established, the importance of Bacillus subtilis-infecting bacteriophages on soybean fermentation is poorly-studied. In this study, we isolated a B. subtilis-infecting bacteriophage BSP10 from Meju (a brick of dried fermented soybean) and further characterized it. This Myoviridae family bacteriophage exhibited a narrow host range against B. subtilis strains (17/52, 32.7%). The genome of bacteriophage BSP10 is 153,767 bp long with 236 open reading frames and 5 tRNAs. Comparative genomics (using dot plot, progressiveMauve alignment, heat-plot, and BLASTN) and phylogenetic analysis strongly suggest its incorporation as a new species in the Nit1virus genus. Furthermore, bacteriophage BSP10 was efficient in the growth inhibition of B. subtilis ATCC 15245 in liquid culture and in Cheonggukjang (a soybean fermented food) fermentation. Artificial contamination of as low as 102 PFU/g of bacteriophage BSP10 during Cheonggukjang fermentation significantly reduced bacterial numbers by up to 112 fold in comparison to the control (no bacteriophage). Moreover, for the first time, we experimentally proved that B. subtilis-infecting bacteriophage greatly enhanced poly-γ-glutamic acid degradation during soybean fermentation, which is likely to negatively affect the functionalities of Cheonggukjang.
A CRISPR-Cas9-Based Toolkit for Fast and Precise In Vivo Genetic Engineering of Bacillus subtilis Phages
Authors: Schilling Tobias , Dietrich Sascha , Hoppert Michael , Hertel Robert
Published: May 2018

Phages are currently under discussion as a solution for the antibiotic crisis, as they may cure diseases caused by multi-drug-resistant pathogens. However, knowledge of phage biology and genetics is limited, which impedes risk assessment of therapeutic applications. In order to enable advances in phage genetic research, the aim of this work was to create a toolkit for simple and fast genetic engineering of phages recruiting Bacillus subtilis as host system. The model organism B. subtilis represents a non-pathogenic surrogate of its harmful relatives, such as Bacillus anthracis or Bacillus cereus. This toolkit comprises the application CutSPR, a bioinformatic tool for rapid primer design, and facilitates the cloning of specific CRISPR-Cas9-based mutagenesis plasmids. The employment of the prophage-free and super-competent B. subtilis TS01 strain enables an easy and fast introduction of specific constructs for in vivo phage mutagenesis. Clean gene deletions and a functional clean gene insertion into the genome of the model phage vB_BsuP-Goe1 served as proof of concept and demonstrate reliability and high efficiency. The here presented toolkit allows comprehensive investigation of the diverse phage genetic pool, a better understanding of phage biology, and safe phage applications.
Inhibition of v-rel-Induced Oncogenesis through microRNA Targeting
Authors: Yao Yongxiu , Zhang Yaoyao , Tang Na , Pedrera Miriam , Shen Zhiqiang , Nair Venugopal
Published: May 2018

Several studies have shown that microRNA-targeting is an effective strategy for the selective control of tissue-tropism and pathogenesis of both DNA and RNA viruses. However, the exploitation of microRNA-targeting for the inhibition of transformation by oncogenic viruses has not been studied. The v-rel oncoprotein encoded by reticuloendotheliosis virus T strain (Rev-T) is a member of the rel/NF-κB family of transcription factors capable of transforming primary chicken spleen and bone marrow cells. Here, by engineering the target sequence of endogenous microRNA miR-142 downstream of the v-rel gene in a Replication-Competent ALV (avian leukosis virus) long terminal repeat (LTR) with a splice acceptor (RCAS) vector and using a v-rel-induced transformation model of chicken embryonic splenocyte cultures, we show that hematopoietic-specific miR-142 can inhibit the v-rel-induced transformation, and that this inhibition effect is due to the silencing of v-rel expression. The data supports the idea that microRNA-targeting can be used to inhibit viral oncogene-induced oncogenesis.
Slant of a Surface Shifts Binocular Visual Direction
Authors: Kusano Tsutomu , Shimono Koichi
Published: May 2018

We demonstrate how the slant of a surface affects the relative visual direction between binocular stimuli. In two experiments, we measured the visual direction of a binocular stimulus at different distances in the mid-sagittal plane or in the transverse plane at eye level relative to the center of the stimulus field. Experiment 1 showed that when a binocular stimulus (a vertical bar) was presented in front of or behind a surface slanted along the vertical center of the surface, its visual direction shifted toward the surface. Experiment 2 showed that when a binocular stimulus (a horizontal bar) was presented in front of or behind a surface slanted along the horizontal center of the surface, its visual direction also shifted toward the surface. These results indicate that the slant of a surface should be listed among the variables that contribute to the binocular visual direction, as well as the retinal loci of the stimulus, binocular eye position, the location of the visual egocenter, and stimulus properties.
Quantitative Assessment of Flow Regime Alteration Using a Revised Range of Variability Methods
Authors: Ge Jinjin , Peng Wenqi , Huang Wei , Qu Xiaodong , Singh Shailesh Kumar
Published: May 2018

The Ecological Limits of Hydrologic Alteration (ELOHA) framework, which can be used to determine and implement environmental flows at regional scales, requires accurate flow regime alteration assessment. The widely used range of variability approach (RVA) evaluates flow regime alteration by comparing the distribution of 32 Indicators of Hydrologic Alteration (IHA). However, the traditional RVA method is not comprehensive, because it neglects both the human-induced inner characteristics of one hydrological year (ICOHY) and the positional information of 32 IHA, which are the main factors behind ecosystem alteration. To address these limitations, we propose a revised RVA method that uses the Tanimoto similarity (TS) coefficient to reflect the ICOHY and a first-order connectivity index to reflect the IHA positional information. The yearly Tanimoto alteration (TA) index is measured using the revised RVA method, and the individual alteration (IA) values of each of 32 IHA are calculated using the traditional RVA method. Then, a new index, the overall degree of flow regime alteration (OA), is derived from the TA and IA values. The effectiveness of the revised RVA method is tested in the upper reaches of the Yangtze River, and the results suggest that the revised RVA ameliorates the limitations of the traditional RVA, and therefore, is preferable for use in the ELOHA framework.
Assessing the Influence of Precipitation on Shallow Groundwater Table Response Using a Combination of Singular Value Decomposition and Cross-Wavelet Approaches
Authors: Qi Peng , Zhang Guangxin , Xu Y. Jun , Wang Lei , Ding Changchun , Cheng Chunyang
Published: May 2018

Identifying the spatiotemporal change of the groundwater table to precipitation at the river basin scale can be important for regional water resource management. In this study, we proposed a method that combines singular value decomposition and cross-wavelet approaches to analyze the relationship between groundwater level dynamics and precipitation. The method was applied to the Naoli River Basin, Northeast China. Moreover, the method of continuous wavelet using fast Fourier transform was also used to reveal clearly the relationship between groundwater level and heavy precipitation. The results showed that the major mode of relationship between groundwater and precipitation was divided into four patterns in the study area. In general, the lag time is 27.4 (standard deviation: ±8.1) days in pattern 1, 107.5 (standard deviation: ±13.2) days in pattern 2, 139.9 (standard deviation: ±11.2) days in pattern 3, and 173.4 (standard deviation: ±20.3) days in pattern 4, respectively. In addition, the response of groundwater level dynamics is very sensitive to heavy precipitation in all patterns. Therefore, enhancing the utilization of heavy rainfall and flood resources is an effective way to increase groundwater recharge in this basin.
Ecological Flow Assessment to Improve the Spawning Habitat for the Four Major Species of Carp of the Yangtze River: A Study on Habitat Suitability Based on Ultrasonic Telemetry
Authors: Yu Lixiong , Lin Junqiang , Chen Daqing , Duan Xinbin , Peng Qidong , Liu Shaoping
Published: May 2018

Four major species of Chinese carp, namely black carp (Mylopharyngodon piceus), grass carp (Ctenopharyngodon idellus), silver carp (Hypophthalmichthys molitrix) and bighead carp (Hypophthalmichthys nobilis), are important economic freshwater fish varieties in China. They primarily inhabit and breed in the Yangtze River. Unfortunately, the construction and operation of the Gezhouba Dam and the Three Gorges Dam have dramatically changed the hydrodynamic conditions in the middle reaches of the Yangtze River, leading to a sharp decline in the reproduction rates of these carp. The egg abundance of the four species of carp downstream from the Three Gorges Dam reached 8.35 billion in 1965, but abundance during 2005–2012 was only 0.25 billion. One of the main reasons was that the hydrodynamic conditions of the spawning ground could not meet the four species’ breeding requirements. However, due to the limitations of traditional detection tools, the spawning characteristics of these four species of carp were still unclear. In this study, the ultrasonic telemetry and a three–dimensional hydrodynamic model were utilized to build the habitat suitability index (HSI) curves for the four species of carp. The habitat suitability model was then built based on HSI curves to assess spawning habitat quantity under different flow conditions. Finally, the habitat suitability model in the Yidu spawning ground was validated using 32 groups of sampling data in 2015 and 2017. The statistical results showed that the most suitable velocity ranged from 0.78 m/s to 0.93 m/s. The most suitable water depth ranged from 14.56 m to 16.35 m, and the most suitable Froude number ranged from 0.049 to 0.129. The habitat suitability model simulation results indicated that when the discharge was between 15,000 m3/s and 21,300 m3/s, the weighted usable area (WUA) values in both the Yidu and Zhicheng spawning grounds would remain at a high level. The validation results showed that most spawning activities occurred at a high level of WUA, and that the daily spawning egg numbers increased with the WUA value. Therefore, discharges of between 15,000 m3/s and 21,300 m3/s could be recommended as ecological operation target flows. We propose a feasible ecological operation scheme by setting the initial flow at 15,000 m3/s and maintaining the daily discharge increase at 1500 m3/s for 4 days.
Simulation of Soil Wetting Pattern of Vertical Moistube-Irrigation
Authors: Fan Yan-Wei , Huang Ning , Zhang Jie , Zhao Tong
Published: May 2018

Knowledge of the soil wetting pattern characteristics of vertical moistube-irrigation is essential for the design of cost-effective and efficient irrigation systems. We conducted laboratory experiments to determine the specific discharge calculation formula and compare the accuracy of HYDRUS-2D simulation. The cumulative infiltrations, wetting pattern distances, and water content distributions predicted with HYDRUS-2D were found to align well with experimental data. The results provide support for using HYDRUS-2D as a tool for investigating and designing moistube-irrigation management practices. Numerical simulations were carried out with HYDRUS-2D to investigate the influence of soil texture, initial water content, pressure head, moistube length, and buried depth on wetting pattern characteristics. There are small differences in the shape of the soil wetting pattern, as well as significant differences in size. The wetting pattern and water content contour are approximately “ellipsoid” around the moistube. Soil texture has a significant effect on the wetting pattern characteristics, the vertical and horizontal wetting front distance, and the wetted soil volume decrease along with the increase of soil clay content. The initial water content, pressure head, and moistube length have great influence on the wetting front distance and the wetted soil volume. Both are positively correlated with the initial water content, pressure head, and length. Moistube buried depth affects the wetting pattern position. The soil wetting pattern decreases synchronously as the buried depth drops.
Phytoplankton Composition and Water Quality of Kamil Abduş Lagoon (Tuzla Lake), Istanbul-Turkey
Authors: Yilmaz Nese , Yardimci Cumhur , Elhag Mohamed , Dumitrache Cristina
Published: May 2018

In the present study, the water quality and pollution status of Kamil Abduş Lagoon (Tuzla Lake), which is located in Istanbul Metropolitan area, were investigated by determining the phytoplankton composition, some physicochemical parameters, and nutrient concentrations. Water samples were collected at 3 sampling sites between February 2016 and January 2017 on a monthly basis. A total of 32 taxa, belonging to Bacillariophyta (12), Charophyta (1), Chlorophyta (4), Cryptophyta (1), Cyanobacteria (5), Euglenozoa (5) and Miozoa (4) divisions were identified. Both freshwater and marine species were recorded in the study area. The presence of mesotrophic and eutrophic species of phytoplankton, high concentrations of chlorophyll-a and nutrients indicated that the trophic level of the lake is near to eutrophic. Water quality parameters studied in the current research were investigated to evaluate the input data significance using Artificial Neural Network analysis, specifically to ensure the limitation of regression analysis overfitting. Due to the fact that the lagoon is under threat by pollution it needs to be urgently protected. Therefore, detailed studies on phytoplankton including physicochemical parameters and nutrients have to be carried out in order to select appropriate management routes for improving the water quality in the lagoon.
Experimental and Numerical Modelling of Bottom Intake Racks with Circular Bars
Authors: Carrillo José M. , García Juan T. , Castillo Luis G.
Published: May 2018

Bottom rack intake systems are one of the most popular structures for diverting water in steep rivers. Intake systems may be used in ephemeral rivers beds to capture part of the runoff flow in the rainy season. Their behavior has mainly been studied in the laboratory. Nevertheless, it is not possible to analyze the whole problem of characterization with traditional methodologies due to the many effects that occur on the bars. Computational fluid dynamics simulations have been considered as a complement to improve the knowledge of the hydraulic phenomenon. However, the geometry of circular racks may be a challenge due to its complexity. After the validation procedure, the numerical models appear to be a good tool to design intake systems. No remarkable differences were obtained between the three two-equation turbulence models tested. The results show differences of less than 1% in flow profile over the rack. Fit curves have been proposed to estimate the flow profile over the rack with r2 > 95%. Expressions to calculate the discharge coefficient and the collected water through the rack in the clear water case have been proposed and show a good agreement with the laboratory data.
Interplay between pairing and correlations in spin-polarized bound states
Authors: Głodzik Szczepan , Kobiałka Aksel , Gorczyca-Goraj Anna , Ptok Andrzej , Górski Grzegorz , Maśka Maciej M , Domański Tadeusz
Published: May 2018

We investigate single and multiple defects embedded in a superconducting host, studying the interplay between the proximity-induced pairing and interactions. We explore the influence of the spin–orbit coupling on energies, polarization and spatial patterns of the bound (Yu–Shiba–Rusinov) states of magnetic impurities in a two-dimensional square lattice. We also address the peculiar bound states in the proximitized Rashba chain, resembling the Majorana quasiparticles, focusing on their magnetic polarization that has been recently reported by S. Jeon et al. (Science 2017, 358, 772). Finally, we study leakage of these polarized Majorana quasiparticles into side-attached nanoscopic regions and confront them with the subgap Kondo effect near to the singlet–doublet phase transition.
Polysubstituted ferrocenes as tunable redox mediators
Authors: Waniek Sven D , Klett Jan , Förster Christoph , Heinze Katja
Published: May 2018

A series of four ferrocenyl ester compounds, 1-methoxycarbonyl- (1), 1,1’-bis(methoxycarbonyl)- (2), 1,1’,3-tris(methoxycarbonyl)- (3) and 1,1’,3,3’-tetrakis(methoxycarbonyl)ferrocene (4), has been studied with respect to their potential use as redox mediators. The impact of the number and position of ester groups present in 1–4 on the electrochemical potential E1/2 is correlated with the sum of Hammett constants. The 1/1+–4/4+ redox couples are chemically stable under the conditions of electrolysis as demonstrated by IR and UV–vis spectroelectrochemical methods. The energies of the C=O stretching vibrations of the ester moieties and the energies of the UV–vis absorptions of 1–4 and 1+–4+ correlate with the number of ester groups. Paramagnetic 1H NMR redox titration experiments give access to the chemical shifts of 1+–4+ and underline the fast electron self-exchange of the ferrocene/ferrocenium redox couples, required for rapid redox mediation in organic electrosynthesis.