bluuebunny/crossref_metadata_2025 huggingface dataset:
Technical condition of apartment buildings in the central regions of Russia
Authors: Balzannikov M I
Published: February 2021

The article notes the presence in Russian cities housing stock of the central regions of a large number of residential apartment buildings, built over 50 years ago and in operation. The bearing capacity of the structures of these houses has significantly decreased. In connection with this carried out a survey of technical condition of houses. For buildings that are for further operation invalid state, the procedure of recognition of their emergency. Analysis of data on the technical condition of apartment buildings showed that in the cities of Kazan, Samara and Volgograd, the physical deterioration of residential buildings is 25-28%, which is less than the average value in Russia, and in Nizhny Novgorod it is significantly higher and amounts to 38%. The data allow us to conclude that in the near future in Nizhny Novgorod one should expect a large number of residential buildings to go into emergency condition. Analysis of indicators of the state of emergency residential buildings in these cities shows that the percentage of the city of Samara operated homes, referred in 2013 to the state of emergency, the largest and is 10.1%, which is significantly higher than the average value in Russia. As one of the main reasons for the incomplete resettlement of emergency houses under the program for the period 2013-2018 indicates “the unknown whereabouts of the owner.” The article concludes that it is possible to increase the efficiency of the resettlement program through operational work with the owners of residential premises of liquidated residential buildings.
Feasibility analysis for revitalisation of unused rail infrastructure
Authors: Sitányiová D , Masarovičová S
Published: February 2021

Abandoned railway stations were constructed to serve as a railway stations but have fallen into disuse, because of different circumstances. Many rural stations and lines were closed with the introduction of new bus services, and also due to increased popularity of cars. Some of them were converted and now they have new functions. The purpose of this article is to introduce the concept of reinvention of rural stations in YOUMOBIL project with emphasis on feasibility of reinvention projects. Article gives an overview how is a typical feasibility study organised. Other parts of this document explain the specifics of YOUMOBIL feasibility studies, good practice of reinvention of disused railway infrastructure and example of YOUMOBIL reinvention pilot project in Brezno. YOUMOBIL makes a valuable contribution, helping rural communities get the most from their abandoned stations, turning stations and their surroundings into welcoming, thriving, and safe gateways and hubs. Working with the rail industry towards improvements, such as better pedestrian and cyclist access, supporting intermodality, running events, workshops or other activities encourages people to use public transport, and support the local community.
Requirements for engineering protection of structures and territories for the safe investment project implementation
Authors: Zhuravlev P A , Marukyan A M
Published: February 2021

The article is devoted to the problems of engineering protection of buildings, structures and territories, when organizing territory, formalising principles (conditions), in accordance with which management and construction solutions for engineering protection arrangement are admitted at the planning and design stages. An integrated approach to the engineering protection arrangement is formulated on the basis of these principles (conditions). The approach requires preparation of an engineering protection project, including general layouts, detailed and specified plans, to develop various project solutions, optimize the design process, assess the prevented damage, justify the investment and estimate the consolidated approximate cost.
Principles of construction technical expertise (expert examination) informatization
Authors: Lazareva N V , Zinoviev A Y , Kochenkova E M
Published: February 2021

The article is devoted to principles of informatization of construction technical expertise (forensic, pre-trial and corporate ones). Information models of capital construction objects are considered in the article, in relation to the area of expertise they should include three components: standard (conceptual), basic (design), and real one. Modern information models, as a rule, include only the first two components, but it is the third component, that is crucial in the development of informatization of construction technical expertise. In this regard, the article defines the process of informatization of construction technical expertise and specifies its components: mediatization, computerization, intellectualization. Each informatization component has its own functionality, connected with its purpose, so the authors present their structuring and functional decomposition. The practical significance of the states, given in the article, is related to improving the efficiency and objectivity of construction technical expertise, as well as ensuring the quality of work, control of the cost and duration of contracts or services.
Economic substantiation of construction of narrow profile hydraulic-fill structures
Authors: Mikhasek A A , Rodionov M V , Mingafin R R
Published: February 2021

Hydraulic-fill structures with free flow of pulp have a flattened transverse profile, especially in cases of hydraulic fill of the structure into water. The flattened profile of the structure demands significant financial and labor costs for its construction, reducing the efficiency of the hydraulic-fill structure. This paper deals with the existing methods for the construction of narrow profile hydraulic-fill structures, their economic indicators; the designs of hydraulic-fill structures using geosynthetic materials developed by the authors, which make it possible to increase their efficiency in comparison with previously known methods, especially when the structures are hydraulically filled into water.
Influence of compaction on the deformation resistance of the sub-ballast layer
Authors: Dobeš P , Ižvolt L
Published: February 2021

In railway practice, the results of static load tests are used most frequently to check the quality of compaction. However, the static load tests are preferably carried out to demonstrate the achievement of the required deformation resistance on the sub-ballast layers. The paper deals with the analysis of measured values of deformation resistance of the sub-ballast layer on the modernised track Považská Teplá - Žilina, depending on the compaction (achieved degree of soil compaction) and the possibility of mutual correlation of these qualitative parameters. In the analysis, the values of deformation resistance and compaction quality (degree of soil compaction) were used as part of the quality diagnostics of the performed work on the part of the modernised section of the line Považská Teplá - Žilina.
Compressive Properties of BFRP and HFRP Bars
Authors: Protchenko K , Salha M , Urbański M , Narloch P
Published: February 2021

Durability of steel reinforced structures is one of the leading problems in construction field nowadays. Currently many studies are focused on the possibility of steel reinforcement replacement in concrete structures with a non-corrosive reinforcement, such as FRP (Fiber Reinforced Polymer) reinforcement. This paper presents and compare the results of compression testing of Basalt (BFRP) and a newly developed type of Hybrid FRP (HFRP) bars. The program examined 30 HFRP bars and 30 BFRP bars with a nominal diameter of 8mm and unbraced free-length varying from 50 to 220 mm. Compressive buckling load strength decreased as free length increased, and the modulus of elasticity under compression for diverse unbraced lengths bars slightly differed, but its value was similar to the modulus of elasticity at tensile. In addition, the test results showed that the ultimate compressive strength of non-buckled HFRP bars as a result of axial compression is about 46% of the ultimate strength. The relationships between the compressive buckling load strength and the unbraced length as well as the optimal unbraced length of the bars were determined. Current research is aiming to contribute the optimization of the transverse reinforcement design and the development of standard regulations in the area of elements with such compressed reinforcement.
Approaches to predicting the characteristics of fireproof materials
Authors: Eremina T , Korolchenko D , Portnov F
Published: February 2021

Planning an experiment is a new approach to research in which mathematical methods are given an active role. Based on the a priori information about the process under study, the researcher chooses some optimal research methodology. The results of the new approach to solving extreme problems depend to a large extent on the optimization of planning for a particular class of problems. The test plan presents a shortened plan of complete factor tests and can be considered acceptable due to the small correlation between affecting factors (AF) and output parameters (OP). The peculiarities of design of new composite materials to ensure safety in the operation of buildings and structures under conditions of man-caused and biogenic threats have been determined. The result of the article is the research using the method of forecasting the characteristics of fireproof materials.
Research of a new flame retardant material with set parameters of operational properties taking into account features of glued wooden structures
Authors: Korolchenko D , Rodionova L
Published: February 2021

The questions of peculiarities of using fireproof composition for glued wooden structures are considered. The results of testing the fire-protective efficiency of the composition, the influence on reducing the combustibility and flammability of wooden structures, compatibility with different glue components of glued wooden structures are given. The results of performance properties estimation are described.
Increasing the economic sustainability of winter road maintenance processes through the use of technological innovation
Authors: Sedivy S , Mikulová L , Florkova Z , Gaspar G
Published: February 2021

Effective road management requires the constant generation of new approaches. It is our duty to focus on improving all technical and process areas of road management, especially in the context of environmental and economic sustainability. Otherwise, we will face the fact that neglected parts will slow down the progress of the whole system. This will be reflected in a reduction in the quality of the infrastructure and increased costs over its life cycle. The approach must be systematic and therefore it is necessary to address the elements that, at first sight, do not have a major impact on other elements contained in the whole structure of road infrastructure management. One of the key areas for improvement is the process of winter road maintenance. It must reflect global climate change, new approaches to the cost-effectiveness of finances spent by users and road managers and, last but not least, the need for modern and safe mobility of goods and people. Advanced technologies such as automated anti-icing spraying systems or predictive monitoring of road structure temperature development are one example. However, these innovations bring not only positive but also negative effects.
Impact of environmental actions on steel structures
Authors: Jančula M , Vičan J , Spiewak A
Published: February 2021

The durability of steel constructions is strongly influenced by damage due to environmental actions, which need to be consider in design and maintenance of new and also existing structures. Corrosion aggressiveness of the atmospheric environment is classified by the corrosion rate, what it represents thickness losses of structural steel. That leads to a smaller resistant area, producing a decrease in the structural performance in terms of resistance, stiffness and ductility. The object of this contribution is to present a partial report of experimental research of corrosion processes influence on steel bridges in Slovakia and Poland.
Optimization of process parameters in Electric Discharge Machining Process of Ti-6Al-4V alloy using hybrid Taguchi based MOORA method
Authors: Srikanth R , Singaravel B , Vinod P , Aravind S , Subodh D
Published: February 2021

Electric Discharge Machining (EDM) process is used where the materials are difficult to machine by conventional methods. Titanium alloy is extensively used in aerospace industries because of its light weight and strength. This titanium alloy can be grouped into hard to cut materials and EDM is preferred for machining. In this work, an attempt is made by machinability analysis of titanium alloy on EDM using non-treated, cryogenically treated and tempered conditioned copper electrodes. The input parameters chosen are current, pulse on time, pulse off time and electrodes with different conditions. The output parameters are investigated include Material Removal Rate (MRR) and Tool Wear Rate (TWR). Taguchi based Multi Objective Optimization Ratio Analysis (MOORA) is used to find value of optimum input and output parameters. The result showed that cryogenically treated with tempered copper electrodes are good in machining performance and proposed Taguchi bases MOORA method has capable of solving multiple objectives simultaneously.
Process performance evaluation in mechanical engineering industries in accordance with ISO 9001
Authors: Naveen Karri , Senanayake Rohan , Selvan Chithirai Pon
Published: February 2021

ISO 9001 standard provides a framework for monitoring, measurement, analysis and evaluation; which is an essence of the quality management system and the prime interest for stakeholders. The annual survey conducted by ISO indicate that majority of ISO 9001 Certificates were issued to “Basic Metal & Fabricated Products” industry. Not much research is carried out from the dimension of management system auditor; where evidence based approach is adopted to determine the conformance against the requirement of ISO 9001. This research study is the outcome of the audit conducted in 385 mechanical engineering companies across ten countries. Five hundred mandays of onsite audit yielded the primary data; gathered by means of Interviewing, Observation and by verifying documented information. This research started with the review of performance evaluation requirements, leading to structured audit in accordance with ISO 19001. An independent and impartial audit was conducted to determine the conformance to ISO 9001. Research data is analyzed by using Jamovi software to understand the degree of conformity to the requirements of performance evaluation.
Investigation of powder mixed electrical discharge machining and process parameters optimization using Taguchi based overall evaluation criteria
Authors: Ashok M- , Niranjan T. , Chokalingam S. , Singaravel B.
Published: February 2021

Electrical Discharge Machining is a type of nontraditional process can be used for machining of hard materials and making of complicated shape.In EDM, the important parameters are tool, workpiece and dielectric liquid. Dielectric liquid is used to enhance ionization during the process. Powder Mixed EDM (PMEDM) is preferred for enhance the process efficiency. In this work, nano alumina (Al2O3) powder is added to the dielectric liquid and the process parameters effects are investigated. Input parameters considered are pulse on time, pulse off time and current. Output parameters considered are rate of material removal, surface quality and wear in electrode. Nano powders are mixed in the ratio of 2% to the EDM oil during the operation with dielectric fluid weight ratio. Process parameters are optimized using Taguchi based Overall Evaluation Criteria (OEC). The result revealed thatPMEDM is enhanced the process efficiency.
Mechanical properties of natural fiber reinforced polylactide composites: A review
Authors: kumar Santosh , Shamprasad M S , Varadarajan Y S
Published: February 2021

Nowadays, there is an augmented concern for the development of not only well-designed but also fully sustainable materials. The extraction of renewable resources and disposal processes that would not harm our eco-system is associated with material sustainability. In this respect, biodegradable polymers and natural fibers are suitable alternatives to many non-degradable composites which one lightweight. Many researchers are trying to fabricate composites by adding these two through various means and characterizing their mechanical properties to find the suitability of these for different applications. The present article reviews the literature on the fabrication of polylactide composite reinforced with natural fibers, both of which are biodegradable fully; further, the article reviews the methods used by the researcher for characterizing mechanical properties of these composites.
A Comparative Analysis of Biodiesel Properties Derived from Meat Stall Wastes through Optimized Parameters
Authors: Ravikumar R , Kiran K , Harish Kumar M , Hebbar Gurumoorthy S , Divakara Shetty A S
Published: February 2021

Biodiesel is considered as alternative green fuels that can be used in Internal Combustion engines as a replacement fuel for conventional diesel. Biodiesel is extracted from vegetable and animal sources which are rich in triglycerides. In this work, an attempt has been made to obtain and characterize the biodiesel from animal wastes such as chicken skin and pig tallow which are available in abundance and at an economical cost within the authors’ geographical location. Initially, the feedstock is decontaminated and subjected to conventional heating to convert it into fatty oil. Heating is carried out at different temperatures and for varying time to find out the optimal combination of time and temperature, which would result in maximum fat yield. The fatty oil is then subjected to the trans-esterification process with methyl alcohol in the presence of a catalyst to extract crude biodiesel. A de-canter funnel is used to separate the glycerine and biodiesel from the crude extract. The extracted biodiesel is mixed in different volume percentages with conventional diesel, and various thermochemical properties were evaluated as per ASTM standards. The test result indicated that the properties of the biodiesel blends were well within the limits as prescribed by ASTM standards.
Numerical Investigation of wavy channel using several Nanofluids
Authors: Naik Bharat , Hosmani Anand K. , Kerur Shirish M. , Pattanashetti Jagadeesh S. , Ratan Vinayak , Bhushan Chandra
Published: February 2021

This study investigates the effect of nano-fluids in enhancing heat transfer. These nano-fluids contain nanoparticles (Ag, CuO, Fe, Al2O3 and Tin) in volume fraction ranging between 2%-5%. Two-dimensional numerical simulation has been conducted on wavy channel using ANSYS Fluent. Two dimensional governing equations such as mass, momentum and energy equations are solved using SIMPLE algorithm and discretized using Finite Volume Method. The results show that there will be enhancement of heat transfer rate as the nanoparticle volume concentration increases and from the present study it is clear that silver-water nanofluid gives better results as compared to other nanoparticles.
Machining and forecasting of square profile areas using artificial neural modelling at different slant angles by WEDM.
Authors: Manoj I.V. , Narendranath S
Published: February 2021

Wire electric discharge machining non-conventional process that removes materials by thermal erosion. Tapering in WEDM has many applications in machining accurate geometric profiles. In the present investigation, a slant type taper machining was performed to produce taper profiles with the help of the slant fixture. The machining parameters such as wire guide distance, corner dwell time, wire offset and cutting speed override was employed to find the variation in the taper profile area. A simple square profile of 1mm, 3mm and 5mm was machined at different slant angles namely 0°, 15° and 30°. It was observed that each parameter yielded different profile areas. The artificial neural network was used for the forecasting the areas of 1mm, 3mm and 5mm square for different parameters. The optimum artificial neural network model was experimentally validated and the errors were ranging from 0-10%.
Productivity enhancement of Evacuated Tubes solar still of different water depth: Thermal modelling and an Experimental analysis.
Authors: More Sunil , Daniel Joseph
Published: February 2021

In this research article, the author has conducted the comparative thermal experimental analysis and investigation on Conventional still and Modified Evacuated Tubes solar still with different water volume of 30 and 50 Litre in Basin, in respect of Energy Balance Equation. The various variable elements have been taken into account and duly calculated for both the stills i.e. active still and passive still, based on thermal modelling. The variables calculated comprise inner glass surface temperature, distillate yield, basin water temperature etc. The entire study has been carried out at Akison’s Solar Equipments Pvt. Ltd., Shirwal, Maharashtra, India (latitude18.14° N: longitude 73.97° E), with adequate instrumental infrastructure setup appropriate for the purpose. The investigation concluded that there is substantial escalation of. 242% and 246% at 0.03 and 0.05m of water depth respectively in the yields obtained from Modified Evacuated Tubes solar still in comparison of Conventional still. It has been observed that theoretical outcomes from thermal modelling and the outcomes attained from experiments done for simple and modified stills are in respectable consensus.
Design And Fabrication Of Extrusion Machine For Recycling Plastics
Authors: Kumar Sagar , Sooraj R , Vinod Kumar M V
Published: February 2021

The extruder is designed for producing filament that can be used for 3-D printers. The 3-D printer requires a filament having dimension ranging from 2-2.5mm. The quality expected is to obtain continues filament having the specified dimensional range which can be fed in to the 3D printer. Screw extrusion process is adopted to produce filament to fixes cross section. PET pellets were heated between 230° to 250° and pushed through a nozzle. The material experiences compressive and shear force. A continues filament of diameter ranging from 2 to 2.5mm is obtained without any air bubbles and roughness.
Fabrication and Characterization of Aluminum 8011 Alloy and nano Zro2 Metal Matrix Composite
Authors: Thippeswamy J C , Dr.Sathisha N
Published: February 2021

Composites of nano metal matrix produced by stir casting technology have major attractive properties like high ductility, highly conductivity, light weight, and high strength to weight ratio compared to some other approaches. Nano Zro2 particulates with varying weight percentages (2, 4 and 6%) are reinforced with aluminium 8011 using the process of stir casting. Mechanical properties such as tensile, compression and hardness behavior have been investigated. In the current analysis, scanning electron microscopy (SEM) is carried out to show Nano Zro2 particulates are successfully incorporated into the matrix of aluminium 8011 with homogeneous distribution. The findings showed that improved mechanical properties such as tensile strength, compression strength and hardness, were enhanced by increasing weight percentage of Nano Zro2 particulates in the matrix of aluminium 8011.
Comparative Study of Carbide Tools in Turning of High-Chrome White Cast Iron using Hard Turning Methods
Authors: Ravi A.M , Murigendrappa S.M.
Published: February 2021

Thermally enhanced machining (TEM) is a new practice in hard turning of hard materials like White cast iron, Inconel 718 steels etc. Addition of preheating before shear zone improves the elasticity of the material. Before this, Industries invested more capital on toolings and robust machineries/equipments, also it demamed high cost diamond, Cubic boran nitride (CBN) and polyCBN (pCBN) tools. This research paper mainly focusses on the comparative study of machinability characteristics like machining forces and surface roughness of a high hard High chrome white cast iron (HCWCI) when turning with and without the addition preheat using multilayer hard coated carbide (TiC/TiCN/Al2O3). Taguchi technique were used to carryout the experimentational work. The experimental and theoretical investigations are done in different phases in order to derive some of the useful process responses like machining forces, surface roughness etc, and to prove Oxy-LPG aided TEM most appropriate methodology to cut HCWCI. Furthermore derived the suitable conditions at which the coated carbide tools perform better. Hence comparative studies of each process responses are required to arrive to the reasonable conclusions.
Effect of addition of bismuth on the vibration analysis of Mg-Al/Mg2Si composites processed using stir casting technique
Authors: Umesh D E , Ramesh Rao D , Shivalingappa D
Published: February 2021

In this work, the experimental and finite element simulation solutions of vibration characteristics of the Mg-Al/Mg2Si composite has been carried out. The influence of the geometrical structures, percentage of bismuth and material properties on the natural frequency and the material damping of the Mg-Al/Mg2Si composites has been studied. The fast fourier transform (FFT) analyzer has been utilized to find the first three natural frequencies and the modal damping experimentally of the said composite. Finite element simulation method also has been adopted to find the natural frequencies and their mode shapes for the Mg-Al/Mg2Si composites specimens. From the results of the experimental and analytical method it is identified that the composite material exhibits the set of natural frequencies and the modal damping. It is also observed that the modal damping increases with increase in the addition of bismuth.
Enhancement of Fracture toughness for Nano SiC reinforced AA7075 MMC’s By Tensile tests and FEM Analysis
Authors: Kallimani Anilkumar S. , Chikkanna N , Suresha P , Hareesha G
Published: February 2021

After the second world war, The Design and development activities in the field of Aerospace took place with a great acceleration and that resulted in to Evolution of new Aluminum alloy materials for Aircraft Structure. Recent research work reveals that particle reinforced Metal matrix composites (PAMC) of aluminum alloy reinforced with silicon carbide reinforcement have shown better mechanical and wear properties. In this work, AA7075 is chosen matrix and Nano silicon carbide(500nm) in the range of (0-8%) were added in terms of weight percentage as reinforcement. Cast MMC samples were fabricated stir casting techniques. Further the specimens were made for XRD study, and for Tensile Test. The 500nm silicon carbide content varies with the 0%, 2%, 4%, 6% &8%wt. fractions. Theoretical Stress intensity values of Compact tension specimen were compared with FEM analysis. And it was observed that higher values of toughness were obtained as the weight percentage increased. Results were compared with pure matrix material in this paper.
Novel Dataset Generation for Indian Brinjal Plant Using Image Data Augmentation
Authors: Gorad Balwant , Kotrappa Dr. Sirbi
Published: February 2021

Machine learning and deep learning have performed outstandingly in many computer tasks to tackle various real-world problems like disease prediction on plants etc. But unfortunately, there are many research areas like disease prediction in the agricultural crops where there is a lack of large-good quality real-world datasets. One way to solve such a problem is by using an available dataset from the internet. The problem of using an available dataset from the internet creates lots of issues. Major issues are using the dataset from different geographical locations which are deployed at other location, model overfitting due to small-sized dataset etc. The main purpose and experimentation done in this research paper are presenting different techniques to increase the size of the Indian Brinjal dataset so that deep learning models can be improved. Here data augmentation techniques to enhance the small-sized image dataset using rotation, channel shift, width shift, height shift, shear transform, brightness, scaling, uniform aspect ratio, zoom, horizontal flipping, and vertical flipping methods are used. At last, a huge high-quality training dataset of size 39,010 is generated from 350 sample images taken from the real field and 1356 high-quality images are generated to validate the model using above mentioned data augmentation techniques.
Passenger data analysis of Titanic using machine learning approach in the context of chances of surviving the disaster
Authors: Haque Md Arfinul , Shivaprasad G , Guruprasad G
Published: February 2021

Titanic disaster occurred about 100 years back but still it attracts the researchers to understand and study that how some passengers survived and others perished. In this work, the characteristics of the passengers will be identified and the relationship of survival chance from the disaster is found. Feature engineering techniques will be performed, where the alphabetic values will be changed to numeric values, the family size will be calculated. Also, we will extract the title from the name, and deck label from ticket number. Classification is done using Decision tree machine learning classification algorithm using two classes which are survived and not survived. R programming has been used for its implementation. Clustering is performed using KMeans machine learning algorithm. Its implementation has been done using Python programming.
Microstructure evolution and stress rupture properties of A286 superalloy in the 600 to 750 °C temperature range
Authors: Wei Li , Zhao Hongjin , Sun Yongqing , Zhang Yan , Zhao Bo , Liu Zhenbao , Liang Jianxiong , Yang Zhiyong
Published: February 2021

To study the stress rupture properties of the A286 alloy in high temperature service environment, the stress rupture tests of A286 alloy at different temperature ranges and stress levels were carried out. Moreover, the Larson-Miller Parameter (LMP) for predicting the rupture life was established as LMP = (T + 273)(log t

r
+ C) × 10−3, C = 22.3. The fracture morphology and the microstructure evolution of the stress rupture specimens were observed by scanning electron microscopy. The results show that for the stress rupture tests at 700 °C–750 °C/150–400 MPa, the precipitation of the closely arranged cellular η phase and the coarse MC at the grain boundary acted as the crack source. For the stress rupture test at 600 °C–700 °C/400–700 MPa, the coarse MC at the grain boundary led to stress concentration to give rise to crack initiation and propagation during deformation. With decreasing of temperature and increasing of stress, the fracture mode of the A286 alloy changed from the ductile fracture mode of microvoids to the brittle fracture mode of intergranular. The deformation mechanisms of A286 alloy at different temperatures and stress levels also have been systematically analyzed by transmission electron microscopy. The deformation mechanisms of A286 at different temperatures and stress levels were Orowan looping, microtwins and dislocation pairs shearing with Orowan looping and microtwins as the dominant deformation mechanisms. The critical transition radius of γ′ phase during the transition from dislocation shearing mechanism to Orowan looping mechanism was calculated.
Effect of acrylonitrile styrene acrylate on mechanical, thermal and three-body abrasion behaviors of eucalyptus fiber reinforced polyvinyl chloride composite
Authors: Zhang Keping , Hamza Bichi Abdulmalik , Yang Junqian
Published: February 2021

The effect of different content (0–20 wt%) Acrylonitrile-styrene-acrylic (ASA) on mechanical, thermal and three-body wear behaviors of eucalyptus fiber/polyvinyl chloride (EF/PVC) composites were studied in this research. The results show that the mechanical properties of the composites such as impact strength, tensile strength, flexural strength and flexural modulus increased with increasing ASA content lower than 15 wt%. The addition of 15 wt% and 20 wt% ASA can improve thermal stability of the EF/PVC composites in the early period of the heating, and the effect weakened on later stage due to the thermal degradation of ASA, which occurred in the temperature range 416°C–442°C. The three-body wear resistance of the EF/PVC composites can be improved by ASA, and the abrasive wear mechanism of the composites was predominated by linear travel, sand particle plough and cut action, ASA and PVC plastic deformation, and fibers debonding.
Structural and magnetic phase diagram of epitaxial La0.7Sr0.3MnO3 from first principles
Authors: Pilo J , Pruneda M , Bristowe N C
Published: February 2021

ABO3 perovskites host a huge range of symmetry lowering structural distortions, each of which can tune, or even switch on or off, different functional properties due to the strong coupling between the lattice, spin and charge degrees of freedom in these materials. The sheer number of different meta-stable structures present in perovskites creates a challenge for materials design via theory and simulation. Here, we tackle this issue using a first principles structure searching method on a prototypical half-metallic perovskite, La0.7Sr0.3MnO3, to predict how epitaxial strain can engineer structural and magnetic properties. We reveal a rich structural phase diagram through strain engineering in which the octahedral tilt pattern, and hence the crystal symmetry, is altered from the bulk. We show how the low-symmetry of the various phases in turn induces new structural modes, an increase in the magnetic anisotropy energy, and weak antiferromagnetic spin-canting.
Optical sensors for continuous glucose monitoring
Authors: Yu Ziyi , Jiang Nan , Kazarian Sergei G , Tasoglu Savas , Yetisen Ali K
Published: February 2021

For decades, diabetes mellitus has been of wide concern with its high global prevalence, resulting in increasing social and financial burdens for individuals, clinical systems and governments. Continuous glucose monitoring (CGM) has become a popular alternative to the portable finger-prick glucometers available in the market for the convenience of diabetic patients. Hence, it has attracted much interest in various glucose sensing technologies to develop novel glucose sensors with better performance and longer lifetime, especially non-invasive or minimally invasive glucose sensing. Effort has also been put into finding biocompatible materials for implantable applications to achieve effective in vivo CGM. Here, we review the state-of-the-art researches in the field of CGM. The currently commercially available CGM technologies have been analyzed and a summary is provided of the potential types of recently researched non-invasive glucose monitors. Furthermore, the challenges and advances towards implantable applications have also been introduced and discussed, especially the novel biocompatible hydrogel aimed at minimizing the adverse impact from foreign-body response. In addition, a large variety of promising glucose-sensing technologies under research have been reviewed, from traditional electrochemical-based glucose sensors to novel optical and other electrical glucose sensors. The recent development and achievement of the reviewed glucose sensing technologies are discussed, together with the market analysis in terms of the statistical data for the newly published patents in the related field. Thus, the promising direction for future work in this field could be concluded.
Toward a theory of machine learning
Authors: Vanchurin Vitaly
Published: February 2021

We define a neural network as a septuple consisting of (1) a state vector, (2) an input projection, (3) an output projection, (4) a weight matrix, (5) a bias vector, (6) an activation map and (7) a loss function. We argue that the loss function can be imposed either on the boundary (i.e. input and/or output neurons) or in the bulk (i.e. hidden neurons) for both supervised and unsupervised systems. We apply the principle of maximum entropy to derive a canonical ensemble of the state vectors subject to a constraint imposed on the bulk loss function by a Lagrange multiplier (or an inverse temperature parameter). We show that in an equilibrium the canonical partition function must be a product of two factors: a function of the temperature, and a function of the bias vector and weight matrix. Consequently, the total Shannon entropy consists of two terms which represent, respectively, a thermodynamic entropy and a complexity of the neural network. We derive the first and second laws of learning: during learning the total entropy must decrease until the system reaches an equilibrium (i.e. the second law), and the increment in the loss function must be proportional to the increment in the thermodynamic entropy plus the increment in the complexity (i.e. the first law). We calculate the entropy destruction to show that the efficiency of learning is given by the Laplacian of the total free energy, which is to be maximized in an optimal neural architecture, and explain why the optimization condition is better satisfied in a deep network with a large number of hidden layers. The key properties of the model are verified numerically by training a supervised feedforward neural network using the stochastic gradient descent method. We also discuss a possibility that the entire Universe at its most fundamental level is a neural network.
Going Viral: A Systematic Review of Google Trends in Plastic Surgery and a Recommended Framework for Its Use
Authors: Bellaire Christopher P , Rutland John W , Sayegh Farah , Pesce Rico R , Tijerina Jonathan D , Taub Peter J
Published: February 2021

As the leading global search engine with billions of daily queries, Google and its open-source Google Trends (Google, Mountain View, CA) represent an emerging and powerful tool for epidemiological and medical research. Within the field of plastic surgery, Google Trends has yielded insights into online interest for facial feminization surgery, gender-affirmation surgery, cosmetic body procedures, and breast reconstruction, among other common procedures. The existing literature of Google Trends in plastic surgery was systematically reviewed following established Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Google Trends’ 4 input variables—keyword, region, period, and category—were assessed. Seventeen plastic surgery studies employing Google Trends were reviewed. There was strong inter-rater reliability (Cohen’s kappa = 0.68). Analyzing keyword syntax, only 3 of 17 studies (17.6%) used the “+” function to combine terms, which can significantly improve sensitivity. For the region variable, 12 of 16 studies (75%) conducted worldwide searches; yet, none of the studies used any non-English keywords, introducing significant bias. For the period, 88.2% of studies utilized a timespan of greater than 5 years, resulting in monthly intervals between data points in Google Trends. For the “category” variable, none of the studies appear to have employed the “surgery,” “cosmetic surgery” or “health” categories to improve specificity. Google Trends is presented as an emerging methodology in plastic surgery research. The strengths and limitations of Google Trends as a resource for plastic surgeons and medical professionals are discussed, and a recommended step-by-step guide for conducting and interpreting Google Trends research is outlined.
CuBlock: a cross-platform normalization method for gene-expression microarrays
Authors: Junet Valentin , Farrés Judith , Mas José M , Daura Xavier
Published: February 2021

Motivation

Cross-(multi)platform normalization of gene-expression microarray data remains an unresolved issue. Despite the existence of several algorithms, they are either constrained by the need to normalize all samples of all platforms together, compromising scalability and reuse, by adherence to the platforms of a specific provider, or simply by poor performance. In addition, many of the methods presented in the literature have not been specifically tested against multi-platform data and/or other methods applicable in this context. Thus, we set out to develop a normalization algorithm appropriate for gene-expression studies based on multiple, potentially large microarray sets collected along multiple platforms and at different times, applicable in systematic studies aimed at extracting knowledge from the wealth of microarray data available in public repositories; for example, for the extraction of Real-World Data to complement data from Randomized Controlled Trials. Our main focus or criterion for performance was on the capacity of the algorithm to properly separate samples from different biological groups.

Results

We present CuBlock, an algorithm addressing this objective, together with a strategy to validate cross-platform normalization methods. To validate the algorithm and benchmark it against existing methods, we used two distinct datasets, one specifically generated for testing and standardization purposes and one from an actual experimental study. Using these datasets, we benchmarked CuBlock against ComBat (Johnson et al., 2007), UPC (Piccolo et al., 2013), YuGene (Lê Cao et al., 2014), DBNorm (Meng et al., 2017), Shambhala (Borisov et al., 2019) and a simple log2 transform as reference. We note that many other popular normalization methods are not applicable in this context. CuBlock was the only algorithm in this group that could always and clearly differentiate the underlying biological groups after mixing the data, from up to six different platforms in this study.

Availability and implementation

CuBlock can be downloaded from https://www.mathworks.com/matlabcentral/fileexchange/77882-cublock.

Supplementary information

Supplementary data are available at Bioinformatics online.
MitoFlex: an efficient, high-performance toolkit for animal mitogenome assembly, annotation and visualization
Authors: Li Jun-Yu , Li Wei-Xuan , Wang An-Tai , Zhang Yu
Published: February 2021

MitoFlex is a linux-based mitochondrial genome analysis toolkit, which provides a complete workflow of raw data filtering, de novo assembly, mitochondrial genome identification and annotation for animal High Throughput Sequencing data. The overall performance was compared between MitoFlex and its analogue MitoZ, in terms of protein-coding gene recovery, memory consumption and processing speed.

Availabilityand implementation

MitoFlex is available at https://github.com/Prunoideae/MitoFlex under GPLv3 license.

Supplementary information

Supplementary data are available at Bioinformatics online.
Fossil pollen from early Palaeogene sediments in western India provides phylogenetic insights into divergence history and pollen character evolution in the pantropical family Ebenaceae
Authors: Bansal Mahi , Nagaraju Shivaprakash K , Mishra Ashish Kumar , Selvaraj Jeyakumar , Patnaik Rajeev , Prasad Vandana
Published: February 2021

Many plant families lack substantive fossil records, limiting our understanding of their origin and evolution. The abundance and preservation potential of pollen through geological time have helped to overcome such limitations and have provided reliable fossils for reconstructing biogeographical history and character evolution in many angiosperm families. Here, using scanning electron microscopy, we identified six Ebenaceae-type fossil pollen grains from early Palaeogene sediments of western India. Phenetic and phylogenetic analyses using pollen characters of fossil and extant taxa reavealed affinities of these fossils to three genera of Ebenaceae (Euclea, Royena and Diospyros). Furthermore, our divergence dating analysis using these fossils as priors suggested a Gondwanan origin for the family during the mid-Cretaceous [c. 107 Mya, 95% highest posterior density (HPD): 100–112 Mya] and supports the boreotropical and ‘out of India’ dispersal hypotheses as the most probable explanations for the present global distribution of the family. The study also supports the dispersal of the family into India, from Africa, through the Kohistan–Ladakh Arc during the Palaeocene. Finally, comparative phylogenetic analyses suggest significant synapomorphic and phylogenetic signals for a few selected pollen characters in Ebenaceae. Our findings have important implications for understanding the biogeography and evolution of the highly diverse and ecologically and economically important family Ebenaceae.
Modelling sudden cardiac death risks factors in patients with coronavirus disease of 2019: the hydroxychloroquine and azithromycin case
Authors: Montnach Jérôme , Baró Isabelle , Charpentier Flavien , De Waard Michel , Loussouarn Gildas
Published: February 2021

Aims

Coronavirus disease of 2019 (COVID-19) has rapidly become a worldwide pandemic. Many clinical trials have been initiated to fight the disease. Among those, hydroxychloroquine and azithromycin had initially been suggested to improve clinical outcomes. Despite any demonstrated beneficial effects, they are still in use in some countries but have been reported to prolong the QT interval and induce life-threatening arrhythmia. Since a significant proportion of the world population may be treated with such COVID-19 therapies, evaluation of the arrhythmogenic risk of any candidate drug is needed.

Methods and results

Using the O'Hara-Rudy computer model of human ventricular wedge, we evaluate the arrhythmogenic potential of clinical factors that can further alter repolarization in COVID-19 patients in addition to hydroxychloroquine (HCQ) and azithromycin (AZM) such as tachycardia, hypokalaemia, and subclinical to mild long QT syndrome. Hydroxychloroquine and AZM drugs have little impact on QT duration and do not induce any substrate prone to arrhythmia in COVID-19 patients with normal cardiac repolarization reserve. Nevertheless, in every tested condition in which this reserve is reduced, the model predicts larger electrocardiogram impairments, as with dofetilide. In subclinical conditions, the model suggests that mexiletine limits the deleterious effects of AZM and HCQ.

Conclusion

By studying the HCQ and AZM co-administration case, we show that the easy-to-use O'Hara-Rudy model can be applied to assess the QT-prolongation potential of off-label drugs, beyond HCQ and AZM, in different conditions representative of COVID-19 patients and to evaluate the potential impact of additional drug used to limit the arrhythmogenic risk.
Leveraging Daily Social Experiences to Motivate Healthy Aging
Authors: Charles Susan T , Röcke Christina , Sagha Zadeh Rana , Martin Mike , Boker Steve , Scholz Urte
Published: February 2021

Models of healthy aging highlight the motivating influence of social connections. Social experiences constantly shape our thoughts and behaviors throughout daily life, and these daily processes slowly and consistently influence our health and well-being. In this article, we discuss research that has moved from cross-sectional laboratory designs emphasizing individual behaviors to more naturalistic within-person paradigms linking daily social experiences to emotional, cognitive, and physical well-being. We mention research gaps that need to be filled to advance our knowledge of the powerful forces of the social environment for motivating healthy aging. We also offer future directions to move this research forward. We conclude with an outlook on how to leverage these powerful forces in novel intervention approaches that are sensitive to the constantly changing nature of the person and the environment.