bluuebunny/crossref_metadata_2025 huggingface dataset:
Use of photovoltic systems in the construction of wooden houses in a sustainable standard
Authors: Iringová A , Kovačic M
Published: February 2021

The paper deals with the analysis of the efficiency and application of photovoltic systems in the roof plane and in the perimeter walls in the construction of wooden houses in a sustainable standard. The installation of photovoltic systems is a source of renewable energy in the construction of zero energy buildings with minimal emissions of environmental pollution. Semi-transparent photovoltics integrated in the building (BIPV) is one of the technologies that has the potential to increase the energy efficiency of the building and at the same time aesthetically complete the design of the building. This work deals with the construction and material solution of BIPV systems, including BIPV glazing products, tiles and modules and their application in the architectural solution of a model building.
Improvement of Larsen sheet pile retaining wall structures with the use of coarse-porous concrete
Authors: Mikhasek A A , Rodionov M V , Bezuglov A A
Published: February 2021

The construction of hydraulic structures is associated with a significant amount of construction and installation work. Reducing the cost of building such structures is a vital task. The solution to this problem is to improve the design of the retaining structure by means of combining the sheet pile (flexible structure) and the gravity wall (massive structure) into a single whole. In this case it is assumed that the sheet pile provides protection against negative atmospheric effects on the massive wall and ensures the stability of the structure against displacement. At the same time the gravity wall is made of “low” quality materials, e.g. using waste products - products of concrete crushing and / or coarse-porous concrete on crushed sedimentary rock. The gravity wall reduces the active pressure on the sheet pile wall from the backfill side, and this allows using composite and PVC based sheet piles. This article deals with the modeling of retaining walls with various types of composite sheet piles, types of soil, free height and thickness of the gravity element.
Modal split analysis through the traffic volumes
Authors: Drličiak M , Čelko J , Cingel M
Published: February 2021

The article deals with the analysis of the modal split in Žilina self-region (ŽSK) during the morning and afternoon peak hours. The results are based on a mobility survey in the region. Households and inhabitants were divided into three main groups of the population. The first group characterized the inhabitants in the district towns, the second group in the other towns and the third covered the villages. The modal split was analyzed for all main groups and the most numerous subgroup - economically active people. In parallel with the analysis of mobility data, we analyzed data from the traffic surveys on several congested profiles. From the results, we determined the amount of traffic above the real road capacity limit. In the last part of the article, we present an example of combining data from the mobility and transport surveys. We defined the number of trips that need to be transferred to another transport system - the train.
The influence of the pavement surface texture on the Pendulum Test Value
Authors: Kováč M , Brna M
Published: February 2021

The article deals with the problem of finding a relation between surface texture and skid resistance represented by the Pendulum Test Value. For the texture measurements was used a new device that can capture surface irregularities up to the microtexture level. Besides Pendulum Test Values were also evaluated standard roughness parameters as well as the Mean Profile Depth widely used for pavement surface macrotexture evaluation. The texture parameters were evaluated for both macro- and micro-texture of all tested surfaces. Two groups of surfaces were measured. The first group, represented by reference surfaces with known parameters, was used for evaluation of the reliability of new device as well as for determining the relation between microtexture and pendulum test value. The second group was represented by asphalt mixture specimens designed to create various surfaces with different parameters of both macrotexture and microtexture. The obtained results show that there is no unambiguous direct relation between the size of irregularities and skid resistance. That means that high values of both macro and microtexture won’t have to necessarily mean a high level of friction. The proper size and proportion of both parts in their optimal combination are needed.
Economic aspects of pavement surface degradation in terms of noise pollution in their surroundings
Authors: Trojanová M , Decký M , Ivanovičová A , Hodásová K
Published: February 2021

The morphology of the road surface is changing in time which has a consequence in increasing noise levels in areas near the roads. This fact was determined by measurements on two road sections. The measurements were done using the Statistical Pass-By method. Different types of asphalt surfaces were used on the road sections. The Statistical Pass-by Index (SPBI) was quantified from the measurements, which were carried out over the years. Functions of road surface noise evolution in time were calculated from quantified values of SPBI for both measured road surfaces.
Experimental Investigation on Mechanical and Physical Properties of Bamboo and Sisal Fiber Reinforced Hybrid polyester Composite
Authors: Getu Dawit , Nallamothu Ramesh Babu , Minaye Gashaw , Fentaw Getachew , yigrem Melkamu , Kassa Eshetu
Published: February 2021

In composites, characteristic fibers are arising as minimal effort, lightweight and clearly naturally predominant choices to glass fibers, which are utilized in transportation, aviation and development businesses. The development of composites with their improved form is going on with intensive effort. Composite materials which have low densities are used for structural functions, leading to high strength to weight and high stiffness to weight compared to other conventional structural materials. Composites area unit of low value, bio degradable and simply will reclaimable through thermal strategies. Additionally, to the high fatigue strength to weight magnitude relation and fatigue harm tolerance of the many composites conjointly makes them a gorgeous possibility. The light-weight natural fiber composites improve fuel potency and cut back emissions within the use section of the element, particularly in automotive applications.In this investigation hybrid composite material was prepared and composed of bamboo and Sisal fiber which is reinforced composite with in three different fiber orientation, fabricated by hand layup method. Different fiber orientation of sample was prepared and test was carried out to find the Mechanical Behavior and water absorption tests as per ASTM standard. Micro structure was analyzed by optical microscope. Here observed that varying the fiber orientation of bamboo and sisal reinforced sample produced also vary mechanical properties and Unidirectional 00 fiber orientation was found to have a impact strength and the water absorption is more compared to other fiber orientation whereas bidirectional (00/90 0)fiber orientation was found to be having higher hardness strength than unidirectional 900 and Unidirectional 00 fiber orientation which can be used for nonstructural automotive interior body application.
Effect of Silicon Content on wear and Hardness of Al-Si Alloys
Authors: Hatti Gururaj , Vishwanath V H , Dinesh K R
Published: February 2021

In the current work the Al-Si composite is prepared using stir casting method with variation in the percentage(4%, 6% and 8%) of the Si particles in it. stir casting method is one of the cheapest method for production of Al alloys. The prepared composites of different percentages of Si are investigated for it wears behaviour using Pin-on-Disk machine and other properties like hardness. Characterization of Worn surface of the composite is done using SEM. Among the metallic matrices, the aluminum-based matrix remains the most studied metal matrix material for the production of MMCs. This is largely due to the large variety of properties provided by aluminum-based matrix composites at low manufacturing costs. While many Metal Matrix Composites ( MMCs) are desirable for use in various industrial applications, Aluminum Matrix Composites ( AMCs) are the most commonly used in specialized applications because they combine reasonable strength, low density, durability, machinability, availability, performance and price. In aerospace applications, the excellent tribological characteristics of Al-Si and Al-Sn alloys have led to their widespread use, especially in plain bearings, cylinder liners and internal combustion pistons. It is seen that Si is uniformly distributed in the Al matrix and hardness increases to 71BHN with 8%Si in Al matrix. Further analysis revealed that the microstructure homogeneity of the samples is strongly affected its hardness and Wear rate decreases with increase in Si.
Experimental analysis of Fracture Toughness of EN9 and EN31 Steel under double layer of electroplating materials with different varied thickness
Authors: Kari Basavaraja D , Sowmya C , Naik Ravindra
Published: February 2021

With the advent of technology, there is a need to invent newer plating to improve the strength of the material. In this paper, two materials namely Steel Grades EN9 and EN 31 are considered. These materials are having quite a good industrial applications and are being used in many machine parts manufacture. Some of the widely used applications are in the manufacture of Crank shafts, Cylinders, Gears, Sprockets, aerospace parts and body of the ships and automobile parts mainly its surfaces which require high impact resistance and also wear resistance for increased life of the components. The non-electro plated materials are also having the property of higher abrasion resistance. In this paper, the preparation of the specimen, electro plating techniques adopted for getting varied thickness and their critical characteristics in improving the property of the material are discussed further, a statistical model is proposed to obtain the bench mark for its effective implementation of these materials for its industrial use.
Performance Enhancement of CPC Using Graphical Ray Tracing
Authors: Bargale G H , Chougule Dr N K
Published: February 2021

This paper presents the approach of finding an optimized location of a tubular receiver for a compound parabolic collector (CPC) with 23.06° acceptance angle. At this angle reflected rays concentrate at and directly above the main focus of a parabola. Ray tracing plays vital role in analysing rays falling on collector surface and reflected to the receiver. Using this analysis, solar collectors are often designed or improved to enhance the thermal performance. As compound parabolic collectors (CPC) are non-imaging kind and positioned in E-W direction, they are capable of assembling and reflecting an enormous quantity of radiation to the receiver with least tracking. Ray tracing technique was used to evaluate the performance of CPC. A graphical ray tracing (GRT) with SolidWorks was employed to observe the pattern of solar ray concentration. The main aim was to design CPC for low to medium temperature thermal process heat applications, specifically for Textile industries. It is observed that over one tubular absorbers will work better for CPC to absorb most solar rays and two tubular receivers lined up horizontally enhanced the CPC daily average optical efficiency by up to 15-20% compared to the single tubular receiver with the same diameter. Ray-Tracing analysis would possibly provide necessary contributions to beat design problems, complementing the experimental results obtained through thermal testing and allowing the accomplishment of extra thorough testing outputs with lower experimental requirements.
Design and Development of Portable Electrical Resistance Furnace
Authors: Hosamani Anand K. , Naik Bharat , Kerur Shirish M. , Ratan Vinayak , Bhushan Chandra , Girisha L. , Anvekar Yash , Shivakumar s
Published: February 2021

Casting is a very old technique used for making various parts. There are various types of furnaces used for melting metals and alloys, working on different principles. But we Designed & Developed portable electrical resistance furnace to melt at low cost, environment friendly Metals. Further, the furnace is intended to be able to cling to the melt for necessary amount of time. Both electrical and mechanical aspects of furnace design were presented. Finally, we fabricated a furnace of around 9 kW evaluations with working temperatures closer to l200°C. Constructions of furnace process are discussed and its heating performance was tested by melting aluminium, brass and its alloys. Its operation was discussed to suit the heating requirements for various metals and alloys.
Nanostructured Anti-Glare Coatings for Night Visibility
Authors: Madhusudhana R , Sushma K L , Chandra Sekhar K , Krishnamurthy L. , Gopalakrishne Urs R , Sangamesha M A
Published: February 2021

Anti-glare coatings (AGCs) have progressed into highly effective reflectance and glare minimizing components for several optical and opto-electrical equipment’s. The extent in research and development with the contribution of nanotechnology in opto-electronics has improved the AGCs. The present study is related to the composition of a nanostructured antiglare coating. In general, antiglare films have been widely used to deal with glare but this is not proper for an outdoor usage in glasses. Hence, improvement in performance of night-driving glasses is necessary to reduce the negative effects of headlights glare. In this paper nanostructured antiglare coating layers on glass substrate is done using Zirconium Oxide (ZrO2). The obtained coatings are highly transparent and reflective in nature. Sol–gel method is adopted for the preparation of gel, dip-coating and spin coating technique was employed to develop coatings on glass substrates. The obtained coatings were further characterized by XRD to analyze the phase crystallinity; SEM was used to determine the surface morphology of the coatings, EDX to estimate the elemental composition of the coatings and UV-vis Spectroscope was used to determine the optical properties.
Synthesis and Characterization of Zirconium Oxide (ZrO2) Films on AA5052 and Glass substrates
Authors: Madhusudhana R , Navyashree K C , Krishnamurthy L. , Gopalakrishne Urs R
Published: February 2021

Aluminum alloy has gained lot of importance in Aerospace Industries and Engineering applications because of its strength, high resistance to heat, light weight and durability. In this paper we made an attempt to improve the AA5052 substrates properties by coating Zirconium Oxide (ZrO2) by Sol-Gel Method. Glass substrates were also coated with Zirconium Oxide (ZrO2) coating. The coated AA5052 and glass substrates will be annealed to check the thermal resistance for various time of thermal rig test. Micro crystalline properties and formation of ZrO2 of the coated film is evaluated for surface morphological studies by using Scanning Electron Microscope (SEM) and the elemental composition studies done by EDAX (Energy Dispersive Absorption X-ray Spectrometer).
Physical, chemical and surface morphological characterization of single areca sheath fiber
Authors: Suresh P S , Dilip Kumar K , Dhanalakshmi S , Basavaraju B
Published: February 2021

The technological advance in various streams necessitated the increased demand for lesser weight and minimal cost materials. The concerns to ensure environmental sustainability, those newer materials were expected to be decomposable. In the current study, chemical, physical and mechanical and morphological aspects of areca sheath/frond fiber are investigated. It is observed that, the cellulose, hemicelluloses and lignin wt. % are 65.02, 8.26 and 18.62 respectively. The XRD study confirms the percent crystallinity of 81.33% and the crystallinity index of 0.77. The fiber further exhibited the tensile strength of 59.62±2.20 MPa. The TGA study reveals the higher degradation rate at 322.2 °C and the residual mass at 500 °C is 33.23%. The morphological study is done through scanning electron microscopy (SEM). The other properties such as density (0.9 g/cm3), the fiber length, diameter, and moisture uptake are also reported. From the very promising results, the fiber can be used as a reinforcement agent and the composites may find potential applications in automobile panels, interiors, structural light weight bearing sheets, etc.
Compressive properties of 3D braided flax fiber textile fabric reinforced PLA composites
Authors: Kanakannavar S , Pitchaimani J
Published: February 2021

In this study, fabric woven using 3D braided flax yarn is used to reinforce Poly Lactic Acid (PLA) composites. Solid braiding technique is used to convert the typical yarns into braided yarn and further these yarns are used to prepare woven fabric. Finally, composites are fabricated through layer stacking method using hot-press hydraulic compression moulding machine. Compression and shrinkage tests are performed on the braided composites. The braided flax fiber composite results are compared with the as received PLA polymer results. Results showed significant enhancement in the compression properties of PLA composites due to the braided fabric reinforcement. These properties are further increased with the increase in filler content respectively. Thermal shrinkage of the braided flax fiber composites is lower than the PLA polymer. This is due to the higher thermal sustainability property associated with the braided flax fiber.
Thermodynamic investigation of a SOFC- Steam turbine hybrid system powered by Synthetic gas from Municipal Solid Waste
Authors: Venkitesh K S , Daniel Joseph , Sreekanth Manavalla
Published: February 2021

This study presents the performance evaluation of a system consisting of a Solid oxide fuel cell (SOFC) and steam turbine where the fuel cell is powered by synthetic gas from municipal solid waste (MSW). Analysis is performed based on first and second laws of thermodynamics. The modelling of the system is done in a flow sheeting software Cycle Tempo®. This work mainly focusses on the effective utilization of solid waste by producing the Syngas from gasification. Syngas after cleaning is supplied to the SOFC along with air. The syngas undergoes internal reforming at the fuel cell producing hydrogen which acts as fuel for SOFC. The influence of various operating parameters such as compressor pressure ratio, turbine inlet temperature (TIT), upon thermal efficiency and specific power output are studied. Exergy destruction of various components of the system are also evaluated. The evaluation results are helpful for making suitable modification of the parameters for obtaining optimum configuration of the system.
Production of biodiesel and experimental investigation on IC engine: A review
Authors: Hemanth Kumar B , Manjunath H
Published: February 2021

Due to the depletion and increase in the price of petroleum derived fuel, it is necessary to find out an alternative fuel. Biodiesel is an important alternative fuel source from the non edible oil to fulfil the energy demand. The common way to produce biodiesel from non edible oil is through transesterification. This paper reviews the production of biodiesel using catalysed esterification and factors affecting the biodiesel yield are discussed. This article reported that combustion characteristics of the diesel and biodiesel are similar. Shortened ignition delay, higher ignition pressure, higher ignition temperature were found in the biodiesel blends. The power output and thermal efficiency of the engine fuelled with biodiesel was found to be equivalent to diesel fuel. Emission characteristics of biodiesel found that higher NOx emissions and lower CO and HC emissions due to complete combustion.
Experimental investigation of mechanical properties of Acrylonitrile Butadiene Styrene (ABS) based polymer for Submersible pumps
Authors: Guggari Geetanjali S. , Shivakumar S , Nikhil R , Manjunath G A , Afzal Asif , Ahamed Saleel C.
Published: February 2021

Now a day’s many companies manufacturing the most advanced submersible pumps with Acrylonitrile Butadiene Styrene (ABS) based polymer, which is available in the market for use in domestic, commercial and even research activities. ABS based pumps are widely used in mining, construction and chemical industries. Acrylonitrile Butadiene Styrenehasmuch application in the temperature range from -20 to 80°C. The ABS based polymer composites are used in submergible pumps due their important properties such as corrosion resistance, light weight, erosion resistance, etc. In the current work, the technique used for the fabrication of GFRP- ABS laminateis compression molding, as per the ASTM standard. The various tests are conducted as per Design of Experiments. Analysis of experimental data was performed using Minitab software and tests were conducted for Flexural strength, Inter Laminar Shear Stress, Tensile strength. Three factors areconsidered for the Design of Experiments namely, fibre-to-resin ratio, fibre orientation and period of immersion in artificial sea water. The outcomepoints towards Flexural strength; ILSS and Tensile Strength areat highest along 40:60 fibre-to-resin ratio with 0°/90°fiber orientation, longer the contact to sea water more is the fall in the strength of the composite material and also due to sea water diffusing into the composite material specimen, there is an increase in its weight.
Finite Element Simulation of Fracture Toughness of Al6061 Reinforced with Silicon Carbide
Authors: Hareesha G , Chikkanna N , Doddamani Saleemsab
Published: February 2021

The main objective of the work is to study the fracture behaviour of AA6061-Silicon Carbide material using finite element method. Fracture toughness analysis of AA6061-Silicon Carbide composite has been carried out using finite element methods. Modelling of compact tension specimens was utilized to analyze the fracture toughness using the ANSYS tool. From the results of the comparison, it is recommended that AA6061-9 wt% silicon carbide particulate composite material can be potentially utilized as a replacement of AA6061 in the aerospace application such as helicopter rotor blades.
Performance Investigation of Single-Phase Capacitor Start -Capacitor Run Induction Motor Drive 12 3
Authors: Mr. Antheesh R , Bhat Mr. Subrahmanya , Dr. Rajkiran Ballal I
Published: February 2021

The capacitor-start capacitor-run single-phase induction motors are analyzed by means of double-revolving field theory. This paper presents a practical approach for obtaining equivalent circuit parameters of a single-phase induction motor drive. The mathematical modelling of the machine is done by considering both the rotating fields. The input parameters of a single-phase capacitor-start, capacitor-run induction motor are investigated through simulation and experimental results under normal power frequency operation. The performance of the above single-phase induction motor is analyzed for different load conditions.
Experimental Investigations of Load Characteristics of Induction Motor Drive
Authors: Kumar Mr. Ajithanjaya , Bhat Mr. Subrahmanya , Ballal Dr. Rajkiran
Published: February 2021

The three phase induction motors are most widely used for electric drive applications due to its simple, rugged construction and easy maintenance. Induction motors are considered as workhorse of the industry. This paper presents an experimental investigation of load characteristics along with equivalent circuit parameters of three-phase induction motor drive. The dynamic mathematical model of the machine under different reference frames is analysed with the parameters of the motor obtained through experiments. The equivalent circuit model under steady state is developed; performance of the induction motor is determined form the developed equivalent circuit and the results obtained are verified using the dynamic model under different reference frames. A 5 hp induction motor is used for the experimental verification.
Grain-refining of wire arc additive manufactured aluminum alloy with Nb powder addition
Authors: Zhou Siyu , Wu Ke , Yang Guang , Deng Fangbin , Hou Ning , Qin Lanyun , Wei Wenyi
Published: February 2021

Nb powder with an average diameter of 15 μm was added to the molten pool during wire arc additive manufacturing of 5B06 aluminum alloy. The unmelted Nb with high melting point and the in-situ alloying of Al3Nb acted as heterogeneous nucleation core. The fine equiaxed grains with a diameter less than 50 μm was achieved, and the texture intensity of which was obviously weakened. An improvement in both the ultimate tensile strength and elongation of the Nb added samples were observed, and the micro-hardness of which was also improved due to the refined grain structure.
PASSer: prediction of allosteric sites server
Authors: Tian Hao , Jiang Xi , Tao Peng
Published: February 2021

Allostery is considered important in regulating protein’s activity. Drug development depends on the understanding of allosteric mechanisms, especially the identification of allosteric sites, which is a prerequisite in drug discovery and design. Many computational methods have been developed for allosteric site prediction using pocket features and protein dynamics. Here, we present an ensemble learning method, consisting of eXtreme gradient boosting and graph convolutional neural network, to predict allosteric sites. Our model can learn physical properties and topology without any prior information, and shows good performance under multiple indicators. Prediction results showed that 84.9% of allosteric pockets in the test set appeared in the top 3 positions. The PASSer: Protein Allosteric Sites Server (https://passer.smu.edu), along with a command line interface (https://github.com/smutaogroup/passerCLI) provide insights for further analysis in drug discovery.
A Dictionary of Contemporary World History
Authors: Riches Christopher , Palmowski Jan
Published: February 2021

‘Concise, current information … highly recommended’ – Choice, the magazine of the American Library Association

Over 2,800 entries

The authoritative dictionary provides informative and analytical entries on the most important people, organizations, events, movements, and ideas that have shaped the world we live in. Covering the period from 1900 to the present day, this fully revised and updated new edition presents a global perspective on recent history, with a wide range of new entries from Tony Abbott, the European migration crisis, and ISIS to Narendra Modi, Hassan Rouhani, and UKIP. All existing entries have been brought up to date. Handy tables include lists of office-holders for countries and organizations and winners of the Nobel Peace Prize.

This comprehensive reference resource will be invaluable to students of history, politics, and international relations as well as to journalists, policymakers, and general readers interested in the modern world.
Adaptation in Iranian New Wave Cinema: Social Commentary in Dariush Mehrjui’s The Cow (1969)
Authors: Moradabbasi Fouladi Mazda
Published: February 2021

This article examines the degree to which pre-revolutionary Iranian New Wave cinema is influenced by modern Persian fiction. Considering Iranian film adaptations have barely received any scholarly attention, this article focuses on Dariush Mehrjui’s The Cow/Gav (1969), one of the pioneering films of the New Wave, adapted from Gholamhosein Sa’edi’s story collection entitled The Mourners of Bayal/Azadaran-e Bayal (1965). The rise of the New Wave cinema through the pre-revolutionary years before 1979 was interwoven with the engagement of filmmakers like Mehrjui with Persian fiction. While Sa’edi’s stories present criticisms of the socio-political atmosphere of the late 1960s and 1970s, I argue that Mehrjui’s adaptation complicates Sa’edi’s critical perspective to establish an overt social commentary on contemporary Iranian society. This paper will conclude by demonstrating that Mehrjui in The Cow draws on Sa’edi’s work to portray a microcosm of Iranian society and places it in relation to the motifs of overdependence, fear, religion, and waiting, which are interpretable in the social context of the late 1960s and 1970s. This analysis highlights the invisible yet significant role of modern Persian fiction and adaptation strategies in establishing the perspective of The Cow, which left an impression on many New Wave films.
Propensity Score Weighting and Trimming Strategies for Reducing Variance and Bias of Treatment Effect Estimates: A Simulation Study
Authors: Stürmer Til , Webster-Clark Michael , Lund Jennifer L , Wyss Richard , Ellis Alan R , Lunt Mark , Rothman Kenneth J , Glynn Robert J
Published: February 2021

To extend previous simulations on the performance of propensity score (PS) weighting and trimming methods to settings without and with unmeasured confounding, Poisson outcomes, and various strengths of treatment prediction (PS c statistic), we simulated studies with a binary intended treatment T as a function of 4 measured covariates. We mimicked treatment withheld and last-resort treatment by adding 2 “unmeasured” dichotomous factors that directed treatment to change for some patients in both tails of the PS distribution. The number of outcomes Y was simulated as a Poisson function of T and confounders. We estimated the PS as a function of measured covariates and trimmed the tails of the PS distribution using 3 strategies (“Crump,” “Stürmer,” and “Walker”). After trimming and reestimation, we used alternative PS weights to estimate the treatment effect (rate ratio): inverse probability of treatment weighting, standardized mortality ratio (SMR)-treated, SMR-untreated, the average treatment effect in the overlap population (ATO), matching, and entropy. With no unmeasured confounding, the ATO (123%) and “Crump” trimming (112%) improved relative efficiency compared with untrimmed inverse probability of treatment weighting. With unmeasured confounding, untrimmed estimates were biased irrespective of weighting method, and only Stürmer and Walker trimming consistently reduced bias. In settings where unmeasured confounding (e.g., frailty) may lead physicians to withhold treatment, Stürmer and Walker trimming should be considered before primary analysis.
Neighborhood Sidewalk Environment and Incidence of Dementia in Older Japanese Adults
Authors: Tani Yukako , Hanazato Masamichi , Fujiwara Takeo , Suzuki Norimichi , Kondo Katsunori
Published: February 2021

Sidewalks are indispensable environmental resources for daily life in that they encourage physical activity. However, the proportion of sidewalk coverage is low even in developed countries. We examined the association between neighborhood sidewalk environment and dementia in Japan. We conducted a 3-year follow-up (2010–2013) among participants in the Japan Gerontological Evaluation Study, a population-based cohort study of community-dwelling older adults. We ascertained the incidence of dementia for 76,053 participants from the public long-term care insurance system. We calculated sidewalk coverage (sidewalk area as a percentage of road area) within 436 residential neighborhood units using geographic information systems. Multilevel survival models were used to estimate hazard ratios for the incidence of dementia. During follow-up, 5,310 dementia cases were found. In urban areas, compared with the lowest quartile of sidewalk coverage, the hazard ratio was 0.42 (95% confidence interval: 0.33, 0.54) for the highest quartile, adjusting for individual covariates. After successive adjustments for other neighborhood factors (land slope; numbers of hospitals, grocery stores, parks, railway stations, and bus stops; educational level; and unemployment rate), the hazard ratio remained statistically significant (hazard ratio = 0.71, 95% confidence interval: 0.54, 0.92). Living in a neighborhood with a high level of sidewalk installation was associated with low dementia incidence in urban areas.
Rare earth elements, aluminium and silicon distribution in the fernDicranopteris linearisrevealed by μPIXE Maia analysis
Authors: Liu Wen-Shen , Laird Jamie S , Ryan Chris G , Tang Ye-Tao , Qiu Rong-Liang , Echevarria Guillaume , Morel Jean-Louis , van der Ent Antony
Published: February 2021

Background

The fern Dicranopteris linearis is a hyperaccumulator of rare earth elements (REEs), aluminium (Al) and silicon (Si). However, the physiological mechanisms of tissue-level tolerance of high concentrations of REE and Al, and possible interactions with Si, are currently incompletely known.

Methods

A particle-induced X-ray emission (μPIXE) microprobe with the Maia detector, scanning electron microscopy with energy-dispersive spectroscopy and chemical speciation modelling were used to decipher the localization and biochemistry of REEs, Al and Si in D. linearis during uptake, translocation and sequestration processes.

Results

In the roots >80 % of REEs and Al were in apoplastic fractions, among which the REEs were most significantly co-localized with Si and phosphorus (P) in the epidermis. In the xylem sap, REEs were nearly 100 % present as REEH3SiO42+, without significant differences between the REEs, while 24–45 % of Al was present as Al-citrate and only 1.7–16 % Al was present as AlH3SiO42+. In the pinnules, REEs were mainly concentrated in necrotic lesions and in the epidermis, and REEs and Al were possibly co-deposited within phytoliths (SiO2). Different REEs had similar spatial localizations in the epidermis and exodermis of roots, the necrosis, veins and epidermis of pinnae of D. linearis.

Conclusions

We posit that Si plays a critical role in REE and Al tolerance within the root apoplast, transport within the vascular bundle and sequestration within the blade of D. linearis.
Systematic benchmark of ancient DNA read mapping
Authors: Oliva Adrien , Tobler Raymond , Cooper Alan , Llamas Bastien , Souilmi Yassine
Published: February 2021

The current standard practice for assembling individual genomes involves mapping millions of short DNA sequences (also known as DNA ‘reads’) against a pre-constructed reference genome. Mapping vast amounts of short reads in a timely manner is a computationally challenging task that inevitably produces artefacts, including biases against alleles not found in the reference genome. This reference bias and other mapping artefacts are expected to be exacerbated in ancient DNA (aDNA) studies, which rely on the analysis of low quantities of damaged and very short DNA fragments (~30–80 bp). Nevertheless, the current gold-standard mapping strategies for aDNA studies have effectively remained unchanged for nearly a decade, during which time new software has emerged. In this study, we used simulated aDNA reads from three different human populations to benchmark the performance of 30 distinct mapping strategies implemented across four different read mapping software—BWA-aln, BWA-mem, NovoAlign and Bowtie2—and quantified the impact of reference bias in downstream population genetic analyses. We show that specific NovoAlign, BWA-aln and BWA-mem parameterizations achieve high mapping precision with low levels of reference bias, particularly after filtering out reads with low mapping qualities. However, unbiased NovoAlign results required the use of an IUPAC reference genome. While relevant only to aDNA projects where reference population data are available, the benefit of using an IUPAC reference demonstrates the value of incorporating population genetic information into the aDNA mapping process, echoing recent results based on graph genome representations.
Integrated analysis of the ringneck snakeDiadophis punctatuscomplex (Colubridae: Dipsadidae) in a biodiversity hotspot provides the foundation for conservation reassessment
Authors: Fontanella Frank M , Miles Emily , Strott Polly
Published: February 2021

Species classification may not reflect the underlying/cryptic genetic diversity and focusing on groups that do not represent historically independent units can misdirect conservation efforts. The identification of evolutionarily significant units (ESUs) allows cryptic genetic diversity to be accounted for when designating conservation priorities. We used multi-locus coalescent-based species delimitation methods and multivariate analyses of morphological data to examine whether the subspecies merit conservation recognition and infer the ESUs in ringneck snakes (Diadophis punctatus) throughout the California Floristic Province. Species delimitation methods failed to recover groups consistent with designated subspecies and instead inferred three well supported, mostly geographically isolated lineages. Divergence time estimates suggest that the divergences were driven by historical isolation associated with Pleistocene climate shifts. We found a correlation between increased morphological differentiation and time since divergence, and greater niche similarity between the more recently diverged eastern California and western California groups. Based on these results, we propose that the morphological similarities are due to a combination of morphological conservatism and evolutionary stasis. Our study provides the foundation necessary to re-assess the biodiversity and conservation status of ringneck snakes and offers an important step in unveiling the diversity within the western portion of the genus’ range.
Rapid Screening and Characterization of Triterpene Saponins from the Root of Phytolacca acinosa Roxb by High-Performance Liquid Chromatography Coupled to Electrospray Ionization and Quadrupole Time-of-Flight Mass Spectrometry
Authors: Ling Yun , Zhu Yue , Gan Qiao , Li Guilan , Luo Zefan , Pan Yali , Zhao Lian , Lei Zhineng , He Xin , Zeng Ming , Liu Wenbo
Published: February 2021

Triterpene saponins (TSs) are important bioactive constituents with structural diversity widely distributed in many plants. The root of Phytolacca acinosa Roxb (RPa) has been used as a traditional Chinese medicine. However, TSs as the main active ingredients in RPa have not been fully characterized. Here, we profiled TSs from RPa by high-performance liquid chromatography coupled to electrospray ionization and quadrupole time-of-flight mass spectrometry (HPLC-ESI-QTOF-MS/MS). We tentatively identified 29 TSs, including 13 that had not been reported previously from this plant. This study indicates that HPLC-ESI-QTOF-MS/MS is an effective and rapid method for the characterization of complicated TSs in herbal extracts.
Events associated with DNA replication disruption are not observed in hydrogen peroxide-treated Escherichia coli
Authors: Hoff Chettar A , Schmidt Sierra S , Hackert Brandy J , Worley Travis K , Courcelle Justin , Courcelle Charmain T
Published: February 2021

UV irradiation induces pyrimidine dimers that block polymerases and disrupt the replisome. Restoring replication depends on the recF pathway proteins which process and maintain the replication fork DNA to allow the lesion to be repaired before replication resumes. Oxidative DNA lesions, such as those induced by hydrogen peroxide (H2O2), are often thought to require similar processing events, yet far less is known about how cells process oxidative damage during replication. Here we show that replication is not disrupted by H2O2-induced DNA damage in vivo. Following an initial inhibition, replication resumes in the absence of either lesion removal or RecF-processing. Restoring DNA synthesis depends on the presence of manganese in the medium, which we show is required for replication, but not repair to occur. The results demonstrate that replication is enzymatically inactivated, rather than physically disrupted by H2O2-induced DNA damage; indicate that inactivation is likely caused by oxidation of an iron-dependent replication or replication-associated protein that requires manganese to restore activity and synthesis; and address a long standing paradox as to why oxidative glycosylase mutants are defective in repair, yet not hypersensitive to H2O2. The oxygen-sensitive pausing may represent an adaptation that prevents replication from occurring under potentially lethal or mutagenic conditions.
On the efficiency of type I censored samples
Authors: Kittaneh Omar A , Almorad, Heba , Helal Sara , Majid M A
Published: February 2021

The paper revisits the entropy-based efficiency of the type-I censored sample, which was addressed by several previous works. The main purpose of this work is to provide a comprehensive definition of the efficiency function and give a general proof that the entropy of a censored sample is always less than that of the complete sample for any probability distribution and at any point of censoring. A simulation study is performed to validate our results, and a real-data example is reevaluated.
Incorporating a dynamic gene-based process module into a crop simulation model
Authors: Oliveira Fabio A A , Jones James W , Pavan Willingthon , Bhakta Mehul , Vallejos C Eduardo , Correll Melanie J , Boote Kenneth J , Fernandes José M C , Hölbig Carlos A , Hoogenboom Gerrit
Published: February 2021

Dynamic crop simulation models are tools that predict plant phenotype grown in specific environments for genotypes using genotype-specific parameters (GSPs), often referred to as ‘genetic coefficients’. These GSPs are estimated using phenotypic observations and may not represent ‘true’ genetic information. Instead, estimating GSPs requires experiments to measure phenotypic responses when new cultivars are released. The goal of this study was to evaluate a new approach that incorporates a dynamic gene-based module for simulating time-to-flowering for common bean (Phaseolus vulgaris L.) into an existing dynamic crop model. A multi-environment study that included 187 recombinant inbred lines (RILs) from a bi-parental bean family was conducted in 2011 and 2012 to measure the effects of quantitative trait loci (QTLs), environment (E) and QTL × E interactions across five sites. A dynamic mixed linear model was modified in this study to create a dynamic module that was then integrated into the Cropping System Model (CSM)-CROPGRO-Drybean model. This new hybrid crop model, with the gene-based flowering module replacing the original flowering component, requires allelic make-up of each genotype that is simulated and daily E data. The hybrid model was compared to the original CSM model using the same E data and previously estimated GSPs to simulate time-to-flower. The integrated gene-based module simulated days of first flower agreed closely with observed values (root mean square error of 2.73 days and model efficiency of 0.90) across the five locations and 187 genotypes. The hybrid model with its gene-based module also described most of the G, E and G × E effects on time-to-flower and was able to predict final yield and other outputs simulated by the original CSM. These results provide the first evidence that dynamic crop simulation models can be transformed into gene-based models by replacing an existing process module with a gene-based module for simulating the same process.
The Future of Battery Tech
Authors: Biju Soly Matthew
Published: February 2021

Dr. Soly Mathew Biju MBCS CITP and Alex Mathew explain common problems with lithium-ion batteries and explore technologies that could revolutionise power in everything — from cars to mobile phones.
Defining Digital Capital and Digital Poverty
Authors: Donaghy Dave
Published: February 2021

Dave Donaghy MBCS FRSA CITP CEng, Lead Engineer at Hewlett Packard Enterprise and BCS Council Member, explores how common language may help us to unify our approaches to problems in digital poverty.
AI and US: Engineering a Healthy Relationship
Authors: Choudrie Jyoti
Published: February 2021

Jyoti Choudrie FBCS, Professor of Information Systems at the University of Hertfordshire, talks to Johanna Hamilton AMBCS about COVID-19, sanity checking with seniors, robotics and how AI is shaping our world.
How to Build a Strong it Talent Pipeline
Authors: Dudley Claire
Published: February 2021

When it comes to building an IT talent pipeline, Claire Dudley from QA says culture, engagement, and continuous learning are all important considerations.
Group Meeting Frequency and Borrowers’ Repayment Performance in Microfinance: Evidence from a Quasi-natural Experiment in South Africa
Authors: Dalla Pellegrina Lucia , De Michele Angela , Di Maio Giorgio , Landoni Paolo , Parravicini Susanna
Published: February 2021

A quasi-natural experiment has been carried out at The Small Enterprise Foundation, a South African microfinance institution offering group lending with joint liability. In a pilot project, the frequency of meetings was reduced from fortnightly to monthly and the members of the groups were no more required to attend all the meetings but they could send a representative. After selecting a suitable control group using propensity score matching techniques, we ran difference-in-difference regressions to evaluate the impact of the policy changes. Estimates suggest that the pilot project increased loan repayment delays and decreased groups’ deposits, but it had a negligible impact on groups’ savings balances. Text mining techniques, applied to survey data, pointed towards the lack of trust within the groups whose members did not meet frequently outside the repayment meetings as one of the causes of the negative outcomes of the pilot experiment. We conclude that group meetings are an effective tool to stimulate the accumulation of social capital among microcredit borrowers.
Plasma Protein Profiling by Proximity Extension Assay Technology Reveals Novel Biomarkers of Traumatic Brain Injury—A Pilot Study
Authors: Chen Michelle , Ren Annie H , Prassas Ioannis , Soosaipillai Antoninus , Lim Bryant , Fraser Douglas D , Diamandis Eleftherios P
Published: February 2021

Background

Traumatic brain injury (TBI) is a significant public health issue affecting nearly 69 million patients worldwide per year. Reliable diagnostic biomarkers are urgently needed to aid in disease diagnosis and prognosis and to guide patient aftercare. Blood biomarkers represent an attractive modality to quickly, cheaply, and objectively evaluate clinical status. We hypothesize that deep and quantitative plasma proteomic profiling with a novel technology, proximity extension assay, may lead to the discovery of diagnostic and/or prognostic biomarkers of TBI.

Methods

We used high-throughput proximity extension assays (PEA) to quantify the relative abundance of over 1000 unique proteins in plasma. PEA is a highly sensitive multiplex immunoassay capable of detecting very low-abundance proteins (down to fg/mL) in complex biological matrices. Our patient cohort consisted of severe TBI (sTBI) patients, matched healthy controls, and another non-TBI group that was included in the analysis to validate the specificity of the candidates during the selection process. The obtained protein quantification data was then filtered to identify candidate biomarkers through statistical analysis, literature searches, and comparison to our reference control groups.

Results

Overall, we identified 6 novel candidate TBI biomarkers. Candidates exhibit a significant increase in plasma protein abundance in sTBI when comparing between healthy controls and sTBI patients. Candidates generally had low expression in our reference groups compared with the sTBI group.

Conclusions

Our preliminary findings represent a starting point for future validation. These biomarkers, either alone or in combination, may have significant clinical utility in aiding in TBI diagnosis, prognosis, and/or management.