bluuebunny/crossref_metadata_2025 huggingface dataset:
Electrical Properties Study of Solid Polymer Electrolyte based on PolyCaproLactone/LiCF3SO3Added Plasticizer
Authors: Yulianti Evi , Sudaryanto  , Deswita  , Wahyudianingsih
Published: October 2020

The electrical properties of solid polymer electrolyte based on biodegradable polymer PolyCaproLactone (PCL)/LiCF3SO3with PC plasticizer addition have been studied. Polymer electrolyte membranes were prepared by solution casting technique by varying propylene carbonate (PC) composition (0-60) % weight. The membranes were characterized by the Electrical Impedance Spectroscopy at room temperature to measure its ionic conductivity and other electrical properties such as dielectric constant and tangent loss. The PCL/LiCF3SO3system containing 20% weight PC plasticizer exhibits the highest conductivity of 4.92 x 10−4S/cm at room temperature. The dielectric constant shows decreases with frequency increasing and it depends on dissociation of ions in the polymer electrolyte system. The tangent loss suggests that there are relaxing dipoles in the polymer electrolyte that shift toward higher frequency region. The membrane microstructure also investigated by XRD and the result showed that the PC plasticizer made the PCL/LiCF3SO3system become more amorphous
Study Performance of LiFePO4/Graphite Cylindrical Pouch Cell
Authors: Honggowiranto Wagiyo , Kartini Evvy , Sudjatno Agus
Published: October 2020

Cylindrical cell Lithium ion battery with a pouch casing has been made at the Integrated Battery Laboratory, BATAN. LiFePO4 double sided coated aluminum foil with a thickness of 180 μm is used as a cathode sheet. The anode sheet is made from two-sided artificial graphite coated on copper foil with a thickness of 197 μm. The composition, crystal structure, of the coated LiFePO4 was measured by XRD. Battery cells are built by rolling thin layers of cathode, separator, and anode material into cylindrical shape using a rolling machine. The cylindrical cell is inserted into an aluminum bag and then sealed at 175°C. Cylindrical cell-bag inserted into the Glove Box then filled with ∼ 2.5 ml of LiPF6 electrolyte liquid. A vacuum sealing machine is used to seal the remainder of the bag set at 175 oC. The performance of lithium ion batteries is characterized by using a battery analyzer. LiFePO4 shows a release capacity of 250.00 mAh, with a specific capacity of 124.10 mAh/g in the 1st cycle and 100.20 mAh/g after 100th cycle, at a rate of 0.3C. The cell shows good performance after 100 cycles with 80.74% retention.
Compressive Strength of PPC Based Quaternary Blended Concrete
Authors: Swamy Yadav G , Ayyappa R A , Guruprasad M , Hari Prasad G , Vyshnavi S , Pragnya Ch.
Published: October 2020

Production of sewage sludge is increasing day by day all over the world. By disposing of the sewage sludge the environmental issues take place in the society. Hence the research for replacement of cement using sewage sludge ash is essential to reduce the use of natural resources. Certainly as pond ash also coal ash as waste which compresses of bottom ash and fly ash. They contain the major chemical components which cement contain. So the major aim in this research study is to the best use of Biochar and pond ash in concrete. Concrete M20 specimens are prepared according to IS10262-2019 and by replacing cement with 5% Biochar and sand with 2-30% of pond ash by varying percentages in steps of 2 and the compressive strength was determined finally observed that 20% replacement of pond ash and 5% Biochar is giving the optimum value of compressive strength.
Twitter Sentiment Analysis on Big Data in Spark Framework
Authors: Nirmala Sugirtha Rajini S , Anuradha K , Umadevi S , Mercy Beulah E
Published: October 2020

Earlier for communication between people is something which is delivered by hand from one person to another. In some words, or letter Social Media an important and also an integral part of everyone’s life now days. Twitter is a social media site and its primary purposes are to convert people and allow people to share their thoughts. Twitter an American Microbe Using twitter social media users post their views, opinions and to communicate with messages called as tweets. It is one of the social media that is gaining popularity now days. As of 2014 twitter social media has more than 284 million users are in active in monthly basis and above 500 million messengers sent messages on a daily base. Twitter is created by Jack Dorsey, Noah Class, Biz stone and Evan Willians in March 2006 and it was launched in the month of July in that year. Sentimental analysis means the analysis and classification of the emotions and feelings such as positive thought, negative thought and neutral thought using text analysis techniques within text data. The aim of the proposed analysis is to identify the public opinion using NLP (Natural Language Processing) with n-gram stemming algorithm in Spark framework.
Comparison of Artificial Controller Based MRAS Speed Observer for Field Oriented Control of Induction Motor
Authors: Shareef Sheik Meera , Balaji K
Published: October 2020

In many industrial applications, the varying speed of the motor drives has become essential for the fast dynamic load conditions. Therefore, the detailed analysis of Field Oriented Control (FOC) with the sensor-less technique of induction motor is proposed where the reference speed is obtained from the MRAS speed observer, and fuzzy, ANN based controllers control the speed. The FOC not only control the magnitude but also provides the phasor control. The FOC is one of the sensors less technique. The sensor-less invokes the process of estimating the speed; the proposed MRAS speed observer achieves it. The MRAS speed observer gets the inputs such as current and voltage and then it converts to flux to reference speed. The FOC control the torque and flux components independently, and the flux component is obtained by the current. The fuzzy-based control technique is utilized for the control of the speed of the induction motor. In addition to this paper compares the results of fuzzy, and ANN based speed control methods, the results include the settling time, peak overshoot, ripples and accuracy of the speed. The results have been compared in the virtual environment by the MATLAB tool.
A Genetic Algorithm (GA)-PID Controller for Temperature Control in Shell and Tube Heat Exchanger
Authors: Somasundar Reddy C , Balaji K
Published: October 2020

In Genetic Algorithm tuned PID method for controls the fluid flow in the heat exchanger is presented in this paper. Shell and tube heat exchanger is the most generally utilized types of heat exchanger for heat transfer in many industrial purposes. The exchanger consists of mechanical part and controlling part. Both the modeled to ensure the efficient operation of shell and tube heat exchanger. The mechanical modeling is completely established on the type of applications. The controller only needs the input fluid and output fluid properties such as temperature and flow rate. Hence the primary objective of the paper is to focus on the controller part for enhancing the heat exchanger performance. This paper proposes the Genetic Algorithm tuned-PID controlling technique to make the settling time and overshoot of set point temperature to be less to a greater extent and the results are compared with the conventional PI method with various tuning algorithms [16]. The performance of proposed GA tuned plant has been compared with existing PID controller outputs with the help of MATLAB/Simulink.
Design of Fuzzy-Pid with Landsman Converter (LC) Fed BLDC Drive Using IFOC Controller
Authors: Sundaram A , Romine Peter
Published: October 2020

In this paper, fuzzy - PID control is designed to improve the settling time of DC link voltage of the Photovoltaic (PV) array fed landsman converter (LC). In all platforms such as medicals, automobile the utilization of variable speed drives is increased and which are directs to brushless DC motor demand in increasingly. Indirect Field Oriented Control is used to make precise and robust speed control with ripple minimization of torque. Back-EMF estimation method is contributing with IFOC control for obtaining accuracy speed in sensor-less approach and control the dynamic changes in speed. Dc link voltage of LC is maintained at constant using the Fuzzy-PID control which maintains the BLDC steady state condition while the motor speed at dynamic load as well as set point variation. The performance of IFOC based brushless DC motor is improved with high efficiency and in the MATLAB/Simulink platform the proposed system results are verified.
Traffic Operations and Capacity Analysis in India
Authors: Jagan Mohan Reddy Kandukuru , Srivastava Paritosh
Published: October 2020

This study highlights the concept of capacity analysis along with traffic operations in urban areas in India. First chapter indicates the introduction of this study through which research aims and objectives can be analysed properly. Moreover, research background and rationale of this study can be also highlighted in this chapter. The second chapter discusses the literature review due to which process of traffic operations and capacity analysis of vehicles can be analysed properly. Using model and theories of traffic flow can help in managing the complexities and issues in traffic management system in urban areas in India. The third chapter defines the research methodology through which tools and techniques regarding this research can be analysed successfully. Using philosophy, approach, design and data collection process, adequate information regarding traffic operations and capacity can be recognised properly.
Fusion Strategies for Multimodal Biometric System Using Face and Voice Cues
Authors: Byahatti Poornima , Shettar Madhura S.
Published: October 2020

Deployment of biometric systems in the applications of real world includes the most of unimodal biometric systems. Unimodal biometric system based on the information collected from single source. Sometimes single source of information may not identify the individual correctly because of some limitations such as Non-universality, Noisy data, Intra-class variation, Spoof attacks and Intra-class similarities. Various limitations of unimodal biometric systems are overridden by the multimodal biometric systems which involves multiple sources of information. Multimodal systems can be constructed by fusing of information of multiple modalities. This fusion can take place at various steps of processing such as at image acquisition, extraction of features of the traits, matching of test vectors with trained vectors and during decision taking based on classification. This paper presents a system of multimodal biometrics using face and voice biometric traits by including four fusion methods. Fusion takes place at i) feature level using concatenation of face and voice features, ii) score level using method involving the maximum of mode of scores obtained from two matchers, iii) rank level using borda count & iv) decision level fusion using logical conjunction (AND). Fusing of Log Gabor & Local Binary Pattern (LBP) takes place at the facial feature extraction. The voice features are also fused using Mel Frequency Ceptral coefficients (MFCCs) and Linear Predictive Coefficient features (LPC). Computation of similarity between test feature vectors and training vectors is carried out using Euclidian distance during matching process. KNN Classifier is used during decision making. Performance evaluation of these techniques are also carried out using performance measures such as Accuracy, False Acceptance Rate (FAR), False Rejection Rate (FRR) and ROC curves.
Universal Fast Marching Method to Identify Liver Image
Authors: Siri Sangeeta K , Pramod Kumar S , Gavisiddappa
Published: October 2020

Liver segmentation is of prime importance in modern liver disease diagnosis and analysis. In our paper, random section of liver image is chosen and its histogram is achieved. From histogram, liver pixel intensity range is obtained. Using the range value, threshold segmentation is carried out which detaches the liver from its adjoining organs. Median filter is employed to curtail the noise. The sigmoidal function is applied to improve anatomical structures of image. Then the image is converted into binary called as speed function. The novel algorithm is designed to locate the start points within speed function without user intervention. These start point evolved outwardly using Fast Marching Method till complete periphery of liver is reached. The proposed algorithm is compared with popularly used segmentation algorithms. The results show that proposed segmentation algorithm is robust in approach.
Machine Learning Techniques to Improve the Success Rate in In-Vitro Fertilization (IVF) Procedure
Authors: Sujata Patil N , Madiwalar S M , Aparanji V M
Published: October 2020

In Vitro Fertilization (IVF) usually assesses the embryo quality by visual morphological methods to transfer the potential embryo. But the success rate of IVF still remains low because of variations in selection process. The main objective is to improve the implantation rate by predicting the quality of embryos transferred from Day-2 to Day-3. Here using the Machine Learning techniques, thousands of the images trained together for the Day-2, the selection of embryos to come for the further assessment i.e. for Day-3. This will assist the doctors to check for the quality embryo without human intervention. We have also compared the results obtained by our Artificial Intelligence methods precision of >0.98 and also generalizes the method for potential embryo selection. Around 3000 plus embryo images are trained by CNN based Azure model and the results were validated using the Machine Learning techniques. Potentially viable embryo will help improve the implantation and success rate.
Study of Quasi-Static Compression Behaviour of Hollow Tubes Made of Glass/Epoxy Composite
Authors: Sampath H P , Srinivasa CV , Naik Veeresh
Published: October 2020

Composite materials have been used widely in various engineering fields. Composite materials possess low weight, corrosion resistance property, and specific strength, and due to these facts, composite materials are becoming popular among researches and scientists. Now a day, the glass fibers offer the potential to acts as a reinforcing material for composites alternative to the use of glass fiber, carbon fiber and other man-made fibers. In present work hallow tube composites of epoxy – glass fiber was prepared by hand lay-up technique. Mechanical characterizations of prepared hollow tube composites were carried out. Mechanical results were improved; we considered the hollow tubes of glass fiber and epoxy in different proportions such as 50% of glass fiber and 50% of epoxy, 60% of glass fiber and 40% of epoxy, 66% of glass fiber and 34% of epoxy. The maximum compression strength was obtained in the ratio of 50:50 that is 57.69N/mm2, the maximum load at the peak was obtained in the ratio of 60:40, that is 14.61kN and the maximum deformation at the peak was obtained in the ratio of 60:40 that is 8.03mm.
Comparative Study on Mechanical Properties of SiC/Gr &Al2O3/Gr reinforced AL6061 hybrid metal matrix composites
Authors: Vignesh P , Sureshkumar R , Arun A , Rethinavel S
Published: October 2020

Silicon carbide / Graphite and Alumina / Graphite reinforced AL6061 Hybrid metal matrix composites are fabricated by stir casting (liquid metallurgy) route. Four samples A,B,C,D with varying proportions in both matrix and reinforcements by fixing graphite proportion (5%) constant for all sampled are prepared. Mechanical properties of all the samples are compared with matrix material (AL6061). Scanning electron microscope is used to examine the microstructural characteristics of the composite samples. Mechanical test results exhibit 3.5% (sample C) increase in the hardness number than the base matrix. But, yield and ultimate tensile strength are reduced with all the reinforcements. Microstructural characterisation clearly depicts the presence of cracks, Agglomeration of reinforcements, cast defects on the surface of prepared composites which leads to poor yield and ultimate tensile strength.
Experimental Investigation of Mechanical Properties of Al6061 Reinforced with Iron oxide
Authors: Shivakumar S P , Sharan A S , Sadashivappa K
Published: October 2020

The present work aimed at investigating the mechanical properties of the aluminum matrix composites. The aluminum 6061 alloy as a matrix reinforced with the weight fraction 2, 4 and 6% of particles of iron oxide (Fe2O3) of size 40µmis prepared using the stir casting technique. The prepared specimens are tested as per the standards for tensile, bending, impact and hardness properties of the composite. From the results it is observed that the mechanical properties of the said composite have increased with the increment in the weight percentage of iron oxide up to 4% of reinforcement. The significant reaction between the reinforcement and the matrix forms the better bonding between them. The enhanced mechanical properties of the aluminum-iron oxide composites are due to the fine, well bonded and homogeneous distribution of the iron oxide particles in the aluminum matrix. The maximum improvements were observed at 4 wt% of Fe2O3.
Nonlinear Radiative Heat Transfer of Magnetite(Fe3O4)-Water Nanofluid over Unsteady Stretching Surface with Fluid Particle Suspension
Authors: Srikantha N , Krishnamurthy M R , Praveena M M , Onkarappa K S , Bharathi K , Pujar G H
Published: October 2020

The exploration of the magneto hydrodynamics(MHD) flow and nonlinear radiative heat transfer of magnetite Fe3O4 - H2O nanoparticle with fluid particle suspension over an unsteady stretching sheet is the central theme of the present work. The similarity transformations were employed to transfer the governing partial differential equations into ordinary ones prior to solve numerically using Runge - Kutta - Fehlberg-fourth and fifth order method with shooting technique. The variations of the temperature and velocity distribution and coefficients of heat transfer for magnetic parameter, temperature ratio parameter nanoparticle volume fraction, and thermal radiation parameter are discussed graphically. Comparative analysis of reported ones and present work results was presented and found to be in good agreement.
Performance features enhancements and trade off study of NOx emission of diesel engine by using ternary blends of karanja - cotton seed biodiesel -diesel.
Authors: Rajesh K , Ganesh D B
Published: October 2020

In this work, Karanja and cotton seed biodiesel were blended with the mineral diesel fuel. The effect of addition of the two biodiesels at different proportion were investigated for the performance and oxides of nitrogen emission of the diesel engine. All the blends exabits the higher break thermal efficiency than that of the diesel. Trade- off analysis was done with respect to efficiency, fuel consumption and oxides of nitrogen to reflect the emission pattern.
Comparative Analysis to Identify Efficient Technique for Interfacing BCI System
Authors: Keerthi Kumar M , Parameshachari BD , Prabu S , Ullo Silvia liberata
Published: October 2020

Brain Computer Interfacing (BCI) allows user to control certain devices or objects using human brain. With the availability of various sensors, it is possible to obtain the data from the human brain which controls the physical activities in the brain itself. BCI users can access a system capable of communicating efficiently in a special manner that works based on the brain signals. BCI gives a better platform for physically challenged people to do certain significant functions in their daily routine. The use of brain imaging technologies in BCI helps to enhance the signal quality during the communication among the machines and the human beings. The paper describes some of the research works carried on BCI and its advancements to perform a better communication between the computers and the human brain, by using emerging technologies. This paper also covers the applications, challenges, and future directions of BCI.
Area Efficient Reconfigurable Buffer for NoC Router
Authors: Sendhilkumar N C , Murugesan R
Published: October 2020

In the current research, FPGA-based architecture of the Noc device reconfigurable router is suggested. Proposed router specification entry is done with the Verilog Hardware Description Language. The latest research has a five-channel router and a crossbar switch (east, west, north, south and local). Each channel has buffers and multiplexers. FIFO buffer stores data, and multiplexer monitors the input and output of data. The channel contains FIFO architecture and multiplexers. The crossbar switch is then planned and five other channels. Reducing the number of LUTs in the proposed work decreased the router area. A report is given for the number of LUTs used in a router. Results obtained indicate the area efficiency of the proposed router over existing method.
Design of Optimized Radix-4 FFT Processor with Multiplier Sharing Method
Authors: Manimaran A. , Parasuraman S.
Published: October 2020

To implement the parallel pipelined FFT architecture in OFDM applications. The OFDM has developed in wide band Digital communication. The radix4 algorithm can achieve to reduce the half computational steps compare than the radix2 algorithm and R4MDC is reduces the slices and power consumption than the single path delay feedback. It can be converted into real and imaginary values. To reduce the twiddle factor complexity by using the bit parallel multiplier. It can be exploits the constant twiddle factor when the twiddle factor multiplicatier relocate the twiddle factor multiplications in timing process. The changes can be appeared in multiplications so have to perform the TF at clock signals in two ways data path.
Congestion aware Adaptive Reverse Routing Strategy for Improving QoS in WSN
Authors: Elangovan G , Kumanan T
Published: October 2020

General purpose routing techniques for a WSN cannot be capable to give adequate functioning for various communication. This creates low adaptively provided with a general purpose routing technique ensuing in several connections reaching extremely congested. Ant Colony Optimization-Based Fault-Aware Routing (ACO-FAR) is used to balance the load in WSN. In this scheme, the node can calculate the present routes as well as deviation packets via a least congested path [17]. However, this scheme lacking the efficient awareness of bandwidth distribution, guaranteed quality of service in the WSN. To overcome these problems in this paper, Congestion aware Adaptive Reverse Routing strategy (CARS) for Improving Quality of Service (QoS) in WSN is proposed. It is a highly adaptive congestion free routing algorithms that also allocate traffic more equally and reduce network congestion. Reverse routing is used for diminishes the energy utilization and avoid the multiple retransmission in the network. Average delay as well as throughput is the two parameters that are utilized to calculate the performance of routing strategy. Simulation results demonstrate that throughput 36.76% enhanced dramatically whereas preserving 40.31%lesser latency performance.
Credential Rate based Black hole attack Detection in MANET
Authors: Rameshkumar S G , Mohan G
Published: October 2020

Mobile Ad-hoc Networks (MANETs) are growingly being distributed in protection-essential applications. Since their integral resource-restrained features, they are prostrate to several security attacks as well as a black hole attack is a category of which critically involves data gathering. To defeat that dispute, Credential based Black hole attack Detection in MANET (CRBD) is anticipated for MANETs. In this scheme, the vicinity account (VA) checks node cooperativeness among neighbourhood nodes as well as obtained data-packet account (ODA) checks the data packet forward rate. The black hole attacker has least both ODA as well as VA. In addition, the black hole attacker has highest outstanding energy compared to the neighbour nodes. These parameters isolate the black hole attacker nodes in the network. The simulation examination demonstrates that the least packet loss as well as network delay.
Link Consistency and Energy Efficiency for Improving Throughput in Wireless Sensor Network
Authors: Vijayabaskar K , Kumanan T
Published: October 2020

Wireless Sensor Networks (WSNs) necessitate lifelong links as well as energy efficiency. Also the raising commercialization of WSN, supervising applications visits for increased quality of service (QoS). The formation of the energy proficient as well as consistent link is a vital to maintain the enhancement of the WSN performance. In this object, we introduce a Link Consistency and Energy Efficiency (LCEE) for Improving Throughput in Wireless Sensor Network. In this scheme, the link consistency factor (LCF) is used to measure the node link consistency. This LCF is computed by node consistency, Link quality, node remaining energy as well as Link healthiness. The LCEE method primarily enhances the network lifespan durability by minimizing sensor node energy utilization with almost logical throughput as well as the packet obtained rate while the improvement of the QoS parameters in the WSN.
Elliptic Curve Digital Signature technique based Abnormal Node Detection in Wireless AD HOC Networks
Authors: Deepalakshmi P , Kumanan T
Published: October 2020

This Security, as well as routing Performance, is two significant operations of Wireless ad-hoc networks (WANETs). Even though, several efforts to enhance its secure routing scheme of WANETs continue susceptible to attacks. Contrasting the majority of conventional solutions which avoid the precise problems, this scheme inclines to distinguish the misconduct as well as recognize the abnormal nodes in WANETs. In this paper, the Elliptic Curve Digital Signature technique (ECDST) is used to detect the abnormal node in the WANET. This technique function recognizes the abnormal node as well as isolate that node them from the route. During route discovery, the ECC method utilizing the Weierstrass Elliptic functions for detecting the abnormal node. The abnormal nodes are discovered by signature verification technique on data communication. It attains consistency in routing with disqualifying the link by the utmost weight as well as validates the nodes. This scheme assures node availability, integrity, as well as improves network performance. The observational analyses illustrate that the introduced scheme can notice the abnormal as well as a compromised node in the network.
Damage characterization of heat-treated titanium bio-alloy (Ti–6Al–4V) based on micromechanical modeling
Authors: Rastgordani Shima , Ch Darabi Ali , Kadkhodapour Javad , Hamzeloo Seyed Reza , Khoshbin Mohammadreza , Schmauder Siegfried , Mola Javad
Published: October 2020

In this study, a micromechanical finite element model is proposed based on experimental data and the rule of the mixture (RoM) in order to predict the tensile behavior of mechanical properties of heat-treated dual-phase medical-grade titanium (Ti–6Al–4V). Tensile tests, micro-hardness measurements, and RoM were used to obtain flow curves for the α and β phases. Scanning electron microscopy (SEM) imaging was used to determine phase fractions and to create representative volume elements (RVEs). Furthermore, the Gurson-Tvergaard-Needleman (GTN) damage model was calibrated using the Taguchi design of experiment (DOE) method in order to predict damage in the microstructure and the results were compared to fracture surface obtained using fractography in order to investigate failure mechanisms. The final micromechanical model could accurately predict stress-strain curves and showed that void formation and coalescence is the primary mechanism of failure. Finally, analyses of the surfaces showed that a fully ductile fracture occurs at the failure point, which agrees with the results of the damage model. The results suggest that the proposed model can predict the failure of heat-treated Ti–6Al–4V bio-alloys.
Transport signatures of temperature-induced chemical potential shift and Lifshitz transition in layered type-II Weyl semimetal TaIrTe4
Authors: Jian Yu , Wu Quansheng , Yang Meng , Feng Qi , Duan Junxi , Chen Dongyun , Wang Qinsheng , Xiao Wende , Shi Youguo , Yazyev Oleg V , Yao Yugui
Published: October 2020

Temperature-induced Lifshitz transitions have been identified in several materials. Their chemical potential shows a substantial shift with changing temperature. The common feature of these materials is the coexistence of electron and hole pockets in the vicinity of the chemical potential. Here, we report the observation of temperature-induced chemical potential shift and Lifshitz transition in a layered type-II Weyl semimetal, TaIrTe4. The reversal of the polarity of the Hall resistivity and thermoelectric power (TEP) as the temperature increases clearly signal an appreciable shift of the chemical potential and change of the Fermi surface. It is corroborated by the improving agreement between the experimental TEP and the one calculated with temperature-dependent chemical potential. The complete disappearance of an electron pocket, consistent with the change of the Fermi surface when the chemical potential moves downwards, provides an evident signature of a temperature-induced Lifshitz transition in TaIrTe4.
Uniform boundedness for a predator-prey system with chemotaxis and dormancy of predators
Authors: Dáger René , Navarro Víctor , Negreanu Mihaela
Published: October 2020

This paper deals with a nonlinear system of reaction-diffusion partial differential equations modelling the evolution of a prey-predator biological system with chemotaxis. The system is constituted by three coupled equations: a fully parabolic chemotaxis system describing the behavior of the active predators and preys and an ordinary equation, describing the dynamics of the dormant predators, coupled to it. Chemotaxis in this context affects the active predators so that they move towards the regions where the density of resting eggs (dormant predators) is higher. Under suitable assumptions on the initial data and the coefficients of the system, the global-in-time existence of classical solutions is proved in any space dimension. Besides, numerical simulations are performed to illustrate the behavior of the solutions of the system. The theoretical and numerical findings show that the model considered here can provide very interesting and complex dynamics.
Elevated Mating Frequency in Honey Bee (Hymenoptera: Apidae) Queens Exposed to the Miticide Amitraz During Development
Authors: Walsh Elizabeth M , Janowiecki Mark A , Zhu Kyle , Ing Nancy H , Vargo Edward Lind , Rangel Juliana
Published: October 2020

Most honey bee (Apis mellifera Linnaeus, 1758) (Hymenoptera: Apidae) colonies in the United States have been exposed to the beekeeper-applied miticides amitraz, coumaphos, and tau-fluvalinate. Colonies are also often exposed to agrochemicals, which bees encounter on foraging trips. These and other lipophilic pesticides bind to the beeswax matrix of comb, exposing developing bees. We explored whether queen-rearing beeswax containing pesticides affects the reproductive health of mated queens. We predicted that queens reared in pesticide-free beeswax would have higher mating frequencies and sperm viability of stored sperm compared with queens reared in wax containing pesticides. Mating frequency and sperm viability are two traditional measurements associated with queen reproductive health. To test these hypotheses, we reared queens in beeswax-coated cups that were pesticide free or contained field-relevant concentrations of 1) amitraz, 2) a combination of tau-fluvalinate and coumaphos, or 3) a combination of the agrochemicals chlorothalonil and chlorpyrifos. We then collected queens once they mated to determine sperm viability, using a dual fluorescent cell counter, and mating frequency, genotyping immature worker offspring at eight polymorphic microsatellite loci. Sperm viability did not differ between control queens and those reared in pesticide-laden wax. However, queens exposed to amitraz during development exhibited higher mating frequency than queens reared in pesticide-free beeswax or beeswax containing the other pesticide combinations. Our results suggest that miticide exposure during development affects queen mating frequency but not sperm viability, at least in newly mated queens. This finding, which has practical implications for commercial queen rearing and overall colony health, calls for further study.
Are Insects Heading Toward Their First Mass Extinction? Distinguishing Turnover From Crises in Their Fossil Record
Authors: Schachat Sandra R , Labandeira Conrad C
Published: October 2020

Time and again, over hundreds of millions of years, environmental disturbances have caused mass extinctions of animals ranging from reptiles to corals. The anthropogenic loss of species diversity happening now is often discussed as the ‘sixth mass extinction’ in light of the ‘Big Five’ mass extinctions in the fossil record. But insects, whose taxonomic diversity now appears to be threatened by human activity, have a unique extinction history. Prehistoric losses of insect diversity at the levels of order and family appear to have been driven by competition among insect lineages, with biotic replacement ensuring minimal net losses in taxonomic diversity. The end-Permian extinction, the ‘mother of mass extinctions’ in the seas, was more of a faunal turnover than a mass extinction for insects. Insects’ current biotic crisis has been measured in terms of the loss of abundance and biomass (rather than the loss of species, genera, or families) and these are essentially impossible to measure in the fossil record. However, should the ongoing loss of insect abundance and biomass cause the demise of many insect families, the current extinction event may well be the first sudden loss of higher-level insect diversity in our planet’s history. This is not insects’ sixth mass extinction—in fact, it may become their first.
Effectiveness of Personal Protective Equipment in Reducing Skin Exposure to Soluble Platinum
Authors: Linde Stephanus J L , Franken Anja , du Plessis Johannes L
Published: October 2020

Objectives

Various forms of personal protective equipment (PPE), including disposable coveralls and gloves, are used to help reduce skin exposure to soluble platinum in precious metals refineries. We aimed to investigate the effectiveness of PPE in reducing workers’ skin exposure to soluble platinum.

Methods

Thirty precious metals refinery workers were divided into two groups according to their use of PPE and related procedures. Group A (n = 13) used disposable coveralls worn over standard overalls along with long-sleeved rubber gloves, while Group B (n = 17) used standard overalls only and surgical nitrile gloves. The skin (palm, wrist, neck, and forehead) and respiratory exposure of these groups to soluble platinum were concurrently measured (using Ghostwipes™ and MDHS 46/2, respectively) along with their urinary platinum excretion.

Results

Both groups of workers experienced comparable geometric mean (GM) respiratory exposure to soluble platinum (Group A = 0.744 µg m−3 versus Group B = 0.711 µg m−3) (P = 0.789), but significantly lower skin exposure (average of all measured anatomical areas) was found for Group A (Group A = 0.005 µg cm−2 versus Group B = 0.033 µg cm−2) (P = 0.018). Significantly lower skin exposure was measured on the palm (P = 0.017), wrist (P = 0.017), forehead (P = 0.027) of Group A workers compared with Group B. No significant difference was found for the urinary platinum excretion of the two groups (Group A GM = 0.208 µg g−1 creatinine versus Group B GM = 0.361 µg g−1 creatinine) (P = 0.273).

Conclusions

The use of disposable coveralls and long-sleeved rubber gloves, along with strict usage procedures, proved effective in reducing precious metals refinery workers’ skin exposure to soluble platinum.
LightBBB: computational prediction model of blood–brain-barrier penetration based on LightGBM
Authors: Shaker Bilal , Yu Myeong-Sang , Song Jin Sook , Ahn Sunjoo , Ryu Jae Yong , Oh Kwang-Seok , Na Dokyun
Published: October 2020

Motivation

Identification of blood–brain barrier (BBB) permeability of a compound is a major challenge in neurotherapeutic drug discovery. Conventional approaches for BBB permeability measurement are expensive, time-consuming and labor-intensive. BBB permeability is associated with diverse chemical properties of compounds. However, BBB permeability prediction models have been developed using small datasets and limited features, which are usually not practical due to their low coverage of chemical diversity of compounds. Aim of this study is to develop a BBB permeability prediction model using a large dataset for practical applications. This model can be used for facilitated compound screening in the early stage of brain drug discovery.

Results

A dataset of 7162 compounds with BBB permeability (5453 BBB+ and 1709 BBB-) was compiled from the literature, where BBB+ and BBB- denote BBB-permeable and non-permeable compounds, respectively. We trained a machine learning model based on Light Gradient Boosting Machine (LightGBM) algorithm and achieved an overall accuracy of 89%, an area under the curve (AUC) of 0.93, specificity of 0.77 and sensitivity of 0.93, when 10-fold cross-validation was performed. The model was further evaluated using 74 central nerve system compounds (39 BBB+ and 35 BBB-) obtained from the literature and showed an accuracy of 90%, sensitivity of 0.85 and specificity of 0.94. Our model outperforms over existing BBB permeability prediction models.

Availabilityand implementation

The prediction server is available at http://ssbio.cau.ac.kr/software/bbb.
Attributable Cost of Healthcare-Associated Methicillin-Resistant Staphylococcus aureus Infection in a Long-term Care Center
Authors: Nelson Richard E , Lautenbach Ebbing , Chang Nelson , Jones Makoto , Willson Tina , David Michael , Linkin Darren , Glick Henry , Doshi Jalpa A , Stevens Vanessa W
Published: October 2020

Background

Studies have shown that healthcare-associated infections (HAIs) due to methicillin-resistant Staphylococcus aureus (MRSA) can lead to substantial healthcare costs in acute care settings. However, little is known regarding the consequences of these infections on patients in long-term care centers (LTCCs). The purpose of this study was to estimate the attributable cost of MRSA HAIs in LTCCs within the Department of Veterans Affairs (VA).

Methods

We performed a retrospective cohort study of patients admitted to VA LTCCs between 1 January 2009 and 30 September 2015. MRSA HAIs were defined as a positive clinical culture at least 48 hours after LTCC admission so as to exclude community-acquired infections. Positive cultures were further classified by site (sterile or nonsterile). We used multivariable generalized linear models and 2-part models to compare the LTCC and acute care costs between patients with and without an MRSA HAI.

Results

In our primary analysis, there was no difference in LTCC costs between patients with and without a MRSA HAI. There was, however, a significant increase in the odds of being transferred to an acute care facility (odds ratio, 4.40 [95% confidence interval {CI}, 3.40–5.67]) and in acute care costs ($9711 [95% CI, $6961–$12 462]).

Conclusions

Our findings of high cost and increased risk of transfer from LTCC to acute care are important because they highlight the substantial clinical and economic impact of MRSA infections in this population.
Patients’ Willingness and Perspectives Toward Chimeric Antigen Receptor T-Regulatory Cell Therapy for Inflammatory Bowel Diseases
Authors: Vent-Schmidt Jens , Goldsmith Laurie J , Steiner Theodore S
Published: October 2020

Background

Inflammatory bowel disease is a life-changing disease resulting from recurrent intestinal inflammation. Current therapies (eg, steroids and biologics) are associated with mild to severe side effects, and none provide a cure. Recent research has focused on genetically engineering gut-specific anti-inflammatory T-regulatory cells (CAR-Tregs) to control intestinal inflammation, a logistically and conceptually complex approach. The purpose of our study was to understand patients’ willingness to try CAR-Treg given 2 hypothetical scenarios—in a clinical trial or as a new treatment.

Methods

We surveyed people living with inflammatory bowel disease about their willingness to try CAR-Treg. The online survey was developed using patient focus groups and associated literature. We recruited participants through email and social media. We used descriptive and inferential statistics to analyze closed-ended questions and inductive thematic analysis to analyze open-ended follow-up questions.

Results

Survey participants indicated high willingness to try CAR-Treg therapy in both a clinical trial and as a new treatment. Willingness to try was not correlated with disease state or medication history. Women were less likely than men to indicate willingness to participate in a clinical trial. Participants’ reasons for being willing to try CAR-Treg therapy included the wish to change their current treatment and the calling to participate in research. Participants that were not willing to try CAR-Treg mentioned the lack of long-term data and the success of their current therapy.

Conclusions

This is the first study to our knowledge to investigate patient willingness to try CAR-Treg therapy. Our results demonstrate the promise of moving this therapy into clinical practice as most patients indicated willingness to try.
CMBD: a manually curated cancer metabolic biomarker knowledge database
Authors: Chen Jing , Liu Xingyun , Shen Li , Lin Yuxin , Shen Bairong
Published: October 2020

The pathogenesis of cancer is influenced by interactions among genes, proteins, metabolites and other small molecules. Understanding cancer progression at the metabolic level is propitious to the visual decoding of changes in living organisms. To date, a large number of metabolic biomarkers in cancer have been measured and reported, which provide an alternative method for cancer precision diagnosis, treatment and prognosis. To systematically understand the heterogeneity of cancers, we developed the database CMBD to integrate the cancer metabolic biomarkers scattered over literatures in PubMed. At present, CMBD contains 438 manually curated relationships between 282 biomarkers and 76 cancer subtypes of 18 tissues reported in 248 literatures. Users can access the comprehensive metabolic biomarker information about cancers, references, clinical samples and their relationships from our online database. As case studies, pathway analysis was performed on the metabolic biomarkers of breast and prostate cancers, respectively. ‘Phenylalanine, tyrosine and tryptophan biosynthesis’, ‘phenylalanine metabolism’ and ‘primary bile acid biosynthesis’ were identified as playing key roles in breast cancer. ‘Glyoxylate and dicarboxylate metabolism’, ‘citrate cycle (TCA cycle)’, and ‘alanine, aspartate and glutamate metabolism’ have important functions in prostate cancer. These findings provide us with an understanding of the metabolic pathway of cancer initiation and progression.

Database URL: http://www.sysbio.org.cn/CMBD/
Advanced achalasia: good candidate for peroral endoscopic myotomy
Authors: Qiu Shaotian , Chai Ningli , Zhai Yaqi , Wang Xiangyao , Wang Yan , Linghu Enqiang
Published: October 2020

Peroral endoscopic myotomy (POEM) has been increasingly accepted as the first-line treatment of achalasia. However, laparoscopic Heller myotomy or esophagectomy still remains as the mainstay treatment for advanced achalasia featured with megaesophagus and/or sigmoid-shaped esophagus. Although the efficacy of POEM for advanced achalasia with sigmoid-shaped esophagus has been described, little is known about the role of POEM for patients with megaesophagus. The aim of our study is to evaluate the efficacy and safety of POEM for advanced achalasia with megaesophagus. Patients who received initial examinations and underwent POEM in our hospital from June 2013 to December 2018 were identified and data were retrospectively analyzed. The advanced achalasia was defined as megaesophagus with a diameter of ≥6 cm. The primary outcome was clinical success. The secondary outcomes were technical success and adverse events. A total of 112 patients (50 females, 44.6%) were included with a mean age of 44.8 years. The median symptom duration was 6.5 years (IQR:3.0–13.0 years). Modified POEM techniques were used in 27.7% (31/112) of patients. Technical success rate was 99.1% (112/113) per procedure. Clinical success was seen in 93.1% patients with median Eckardt score decreasing from 8.0 to 1.0 (P < 0.001) during a median 31.0 months of follow-up. The mean LES pressure decreased from 29.5 mmHg to 14.2 mmHg after POEM (P < 0.05). Procedure-related adverse events occurred in 8.9% patients. Reflux disease was observed postoperatively in 26.7% of patients. POEM is also indicated for patients with advanced achalasia with a favorable safety and efficacy.
Reflection and transmission coefficient approximations for P, S1 and S2 waves in triclinic media
Authors: Jin Song , Stovas Alexey
Published: October 2020

The conventional assumptions, in most published approximations of the reflection and transmission (R/T) coefficients of plane waves at a plane interface between two anisotropic half-spaces, confine their applications to weakly anisotropic and/or weak contrast models. We consider the horizontal interface enclosed by two triclinic half-spaces to approximate the R/T coefficients normalized by the vertical energy flux. The homogeneous background medium can be anisotropic with arbitrary symmetry to better simulate the strongly anisotropic media. The second-order approximations are proposed to accommodate the strong contrast interface. We also consider an isotropic background medium under the weak anisotropy assumption. The obtained approximations can be applied to P, S1 and S2 waves, except for the transmission coefficients between the S1 and S2 waves. The S-wave transmission coefficients are insensitive to the model parameter contrasts and predominately rely on the S-wave polarization directions in the half-spaces above and below the interface. The proposed approximations are tested numerically.
Lower Rates of Colorectal Cancer in Patients With Inflammatory Bowel Disease Using Anti-TNF Therapy
Authors: Alkhayyat Motasem , Abureesh Mohammad , Gill Arshpal , Khoudari George , Abou Saleh Mohannad , Mansoor Emad , Regueiro Miguel
Published: October 2020

Background

Chronic inflammation is a key factor for the development of colorectal cancer (CRC) among patients with inflammatory bowel disease (IBD). Despite the increased use of biologic agents in patients with IBD, their impact on colorectal carcinogenesis remains unclear. With the use of a large database, we sought to describe the effect of biologics on CRC among patients with IBD.

Methods

We evaluated a multicenter database (Explorys) consisting of electronic medical records from several U.S. hospitals between 1999 and 2020. A cohort of patients with a diagnosis of IBD was identified. We performed a multivariate analysis to adjust for multiple factors including medical and surgical therapies.

Results

There were a total of 62,007,510 patients in the database between 1999 and 2020. Amongst those, 225,090 (0.36%) individuals had Crohn’s disease and 188,420 (0.30%) had ulcerative colitis. After adjusting for confounding factors using multivariate analysis, patients with IBD were more likely to develop CRC. Among the IBD cohort, patients treated with anti-TNF agents were less likely to develop CRC; patients with Crohn’s disease: odds ratio, 0.69; 95% confidence interval, 0.66-0.73; P < 0.0001 vs patients with ulcerative colitis: odds ratio, 0.78; 95% confidence interval, 0.73-0.83; P < 0.0001.

Conclusions

Patients with IBD who were treated with anti-tumor necrosis factor agents were less likely to develop CRC. Prospective studies are needed to evaluate whether anti-tumor necrosis factor drugs provide a chemoprotective effect in patients with IBD by inflammation control and mucosal healing.