bluuebunny/crossref_metadata_2025 huggingface dataset:
Prospects for using “Smart House” technology in Africa
Authors: Tangning Jiogap F , Abdryashitova A
Published: August 2020

This study aims to present / illustrate that thanks to the growth of new technologies, the effective use of natural resources can be an important factor for the economic development of several African regions. Africa is a continent with the lowest share of “Smart House” construction technology usage. From this study, the minimum requirements for a “Smart House” were determined depending on the level of income of a person in Africa. The parameters of mobile communications for controlling the elements of a “Smart House” are presented. An algorithm of the “Smart House” element power supply system and its various accessories was formed. The use of a “Smart House” construction technology in Africa will reduce financial costs, improve living conditions and increase the population welfare. The technologies implemented will significantly reduce the daily and monthly costs of running a home in African countries. A general analysis of approaches to data transmission over the Internet is also presented, as this is a very important factor in the control and security of “Smart Houses” in remote access mode via mobile phones or computers. Of course, an indispensable condition is the access to this digital technology.
Formation of optimal performance of works during establishment of the complex of objects optimal sequence of establishing objects complex building
Authors: Mailyan Alexander , Afanasiev Grigoriy , Antoniadi Diana , Petrosyan Rima
Published: August 2020

In the complex development of urbanized areas, construction objects differ in spaceplanning and design solutions, construction volume, total area, and cost of construction. In this regard, in the construction of a facility complex, an important factor is the rational choice of the sequence of facility construction to ensure the optimal duration of construction of the entire complex. This problem is solved by the method of organizational and technological modeling, taking into account the availability of a sufficient amount of resources necessary for the parallel construction of several objects simultaneously. The erection of the construction object includes the underground part, the above-ground part, roofing and finishing construction work, which can be organized into rhythmic specialized flows at individual worksites. This allows you to reduce the duration of the construction of each facility and complex as a whole, as well as to determine the temporary reserves and use them to reduce construction time and optimal provision of material and financial resources. The methods of organizational and technological modeling solve the problem of choosing the optimal sequence of work during the construction of a facility complex to reduce construction time. With limited resources, there is an alternative to attracting additional resources or increasing the overall construction time.
Energy consumption of modern residential houses of the same energy efficient classes
Authors: Navaseltsau Uladzimir , Khaletski Vitali , Melnikov Vladimir
Published: August 2020

The aim of the study is to identify and to compare the design and operation demands of thermal energy for heating and ventilation, the search for the reasons of increased energy consumption. For the study, energy-efficient class B houses were selected in terms of specific heat energy consumption for heating and ventilation, which were put into operation in Brest (Belarus Republic) in 2014-2015. The main method for determining the reasons of increased energy consumption was to study the functioning of the heating and ventilation systems of the discussed houses and to survey residents to analyze how they use heating and ventilation systems. The calculated and operation values of the specific consumption of thermal energy for heating and ventilation are determined. Operational specific heat energy consumption for heating and ventilation turned out to be higher than the project ones by 7.2% to 44.7%. A mismatch was found in the energy consumption of houses of the same class in energy efficiency. The main reasons for this are moisture in building structures, a malfunction in the automation of an individual heating unit, and non-use of installed thermostatic valves to regulate the heat transfer of heating devices. Studies have shown that currently in the Republic of Belarus there is no ground to build residential buildings of a higher energy efficiency category than the considered houses.
Multi-span composite beam
Authors: Sergeev M , Rimshin V , Lukin M , Zdralovic N
Published: August 2020

The development of wooden structures tends to create systems, types, elements and types of connection that would allow you to save wood while increasing the load-bearing capacity and best take into account its physical and mechanical features. One of the priority directions is the creation of lightweight composite bent structures based on wood. The scientific novelty of the article consists in the study of multi-span continuous composite beams, the use of which is possible both in new construction and reconstruction. Composite multi-span wood-glued beams with the proposed reinforcement scheme are an experimental design and to date, their work is poorly studied. The essence of the proposed design is to strengthen the lower zones in the spans of the beam and the upper zones of the beam at the location of the support with fiberglass on an epoxy oligomer. To perform the calculations, we set a model of a beam with three spans of 1.5 m. the Load is assumed to be evenly distributed along the entire length of the beam. A comparison of the structure to assess its rationality was carried out with an unreinforced glued beam with the same design scheme. The study found that, in contrast to wooden beams, the strength of composite beams with rational reinforcement of stretched zones increases by 24-27 %, and the deformability decreases by 8-13 %. From the point of view of the work, it is proposed to use the method of vacuum infusion, which is proven, which has a positive effect on technical and economic indicators.
Energy-efficient indicators of panel housing mass construction in the climatic conditions of central Russia
Authors: Modin Artem , Lukin Mikhail , Vlasov Anton , Hisham Ezzy
Published: August 2020

For the design of energy-efficient buildings, it is only necessary to ensure balanced energy consumption. The definition of energy efficiency is inextricably linked to compliance with requirements and economic costs. The concept of energy efficiency does not only apply to a new building. The new design used all the necessary elements. The use of single-layer prefabricated panels in new construction allows for external insulation taking into account the overlap of all monolithic joints. One of the potentially promising methods of thermal insulation of outdoor structures is the use of liquid-ceramic (thermal insulation) coatings. In the course of the study, it was concluded that the surface temperature of the reinforced concrete panel when using two different insulation options has similar indicators. But the difference in the values of the heat flux is 36.2%, i.e. when using liquid-ceramic insulation, the amount of heat transferred through the wall panel is more by 9.67 W / m2. Economic calculation shows that the use of liquid-ceramic insulation has a positive economic effect in comparison with the classical method of wall insulation by 19.56%.
Reasons of cracks in floor slab panel
Authors: Barabanshchikov Yu G , Belkina T V , Semenov K V , Zimin S S , Akimov S V , Vatin N I
Published: August 2020

The article considers the problem of the formation of temperature and cracks in a reinforced concrete floor in thin 400 mm, connected by reinforcing outlets with internal reinforced concrete walls and the outer ring wall of the core of a high-rise building. During the hardening of the laid concrete, the formation of through cracks in the overlapping, extending from the walls and located across the corridor formed by the walls, was observed. The paper analyzes the possible causes of cracking. Cracking occurs due to the restriction of free temperature and shrinkage deformation of the floor slab by a rigid connection with the walls. The direction of the cracks indicates that tensile shrink stresses act along the walls. Cracks form during the cooling of the concrete floor, when the directions of the vectors of shrinkage and thermal deformation coincide. The work gives recommendations for the care of concrete floor structures.
Stressed deformed condition of orthotropic spherical shell, lowered by two circular hole
Authors: Rakhmankulova Barna , Noraliev Nurulla , Djamalov Kamol , Ziyaeva Sholpan
Published: August 2020

Methods of calculating the shell structures from composite materials and studying the concentration of strains near the holes are devoted to a rather large number of works. However, most of the research was carried out within the framework of the classical Kirchhoff-Love hypothesis, which does not take into account the interlayer and lateral shifts characteristic of composite materials. Application of finite elements method to solve the problems on orthotropic shells of composites, weakened by several holes is reported within the improved theory of Timoshenko type. A numerical algorithm has been developed using the finite element method and a software package has been implemented on a computer that makes it possible to solve problems of stress concentration near two apertures in shells of composite materials. Shearing parameter has been studied for its influence on stress concentration near two circular holes internal pressure for orthotropic spherical shells. Specific results are presented for the cases of large and small holes, taking into account the rigidity of the reinforcing elements. Thus, this software package can be applied to the calculation of the elements of shell structures from orthotropic composite materials weakened by several holes.
Conjugated mathematical model for optimal location of industrial objects
Authors: Ravshanov Z , Abdullaeva B , Kubyashev K
Published: August 2020

The urgent problem related to solving the problems of monitoring and predicting the ecological state of the air basin in industrial regions is considered in the paper. It provides a brief review of scientific publications devoted to these problems. A mathematical model has been developed to study, predict and monitor the concentration of harmful substances in the atmosphere. The model takes into account weather and climate conditions, soil erosion, physicomechanical properties of aerosol particles, and other factors affecting the process under consideration as a whole; it is designed for optimal location of newly constructed production facilities.
Thermal aging of bitumen mixtures with crushed sand
Authors: Salikhov Mukhammat , Veyukov Evgeniy
Published: August 2020

Public roads with advanced types of coatings are mainly constructed of asphalt concrete. Along with good performance, they have some disadvantages. One of them is temperature aging. The aging process is inevitable. However, to increase the stability of bituminous mixtures, it is important to study the structure formation and aging processes of bitumen films on the surface of all components separately, including the areas of contact with crushed sand. In order to study the aging processes, the methods of studying the aging of bituminous mixtures have been critically analyzed. Considering the shortcomings of the methods available, a new method has been developed. Based on the experiments performed using this method, we studied the aging processes of bituminous mixtures at the temperature of +150° C for various periods of time. The resulting mathematical models describe the aging process based on the considered factors. The experimental results were analyzed in accordance with the theoretical concepts of the interaction of bitumen films on the surfaces of crushed sand particles of amorphous rocks. The conducted research has practical conclusions.
Ground-penetrating radar survey for the prevention and elimination of emergency situations
Authors: Zakrevskaya L V , Gandelsman I A , Lubin P A
Published: August 2020

This study analyses the results of a survey of an object in emergency state of a building, identifies the causes of damage, proposes a method for eliminating the consequences, draws conclusions about the possibility of preventing such situations and solutions at all stages of identifying defects. According to the results of a georadar inspection of the underground part of the building, it was found that under the concrete slab there is an air gap zone with a capacity of up to 10-30 mm. In this work, to eliminate the emergency situation, is proposed to utilize a complex solution based on clay and a binder. The work identifies the most effective method for diagnosing the state of bases in case of their discontinuity under the erected construction object. According to the results of the study, the sizes of these zones are determined. A clay suspension fills the voids between the particles of sandy soil and creates conditions that exclude the possibility of further penetration of water into the soil mass. The result of the research allowed to save the object for continued operation.
Physical and chemical bases, structural and technological models of constructional thermal insulating lightweight concrete creating
Authors: Yarmakovsky Vyacheslav N , Kadiev David Z
Published: August 2020

Research object is constructional and thermal-insulating lightweight concrete (STILC) with a modified matrix in the direction improving of thermotechnical quality and durability indicators of such concrete, produced with use of porous aggregates of various petrogenesis. Motivation: the development relevance of STILC new modifications with high performance of thermotechnical quality and durability is determined by the fact that the STILC usage in the enclosing structures of buildings will significantly improve their thermal insulation function, operational reliability. Research method: the developed physical and chemical bases, structural and technological models of the modified matrix of STILC are used in researches. Research results: physical and chemical bases, structural and technological models for creating of STILC with high indicators of thermotechnical quality and weather resistance; technologies for manufacturing STILC with rational usage of technogenic formations recycling products; results of determination of thermophysical characteristics, indicators of weather resistance and other indicators of STILC operational quality. Conclusion: fundamentally new modifications of STILC with high indicators of thermal quality and weather resistance, and the main provisions of their manufacturing technology also have been developed. Based on the results of STILC samples testing, the thermophysical and mechanical properties, as well as weather resistance indicators, were determined for use in the calculations and design of enclosing structures with high thermal protection function and reliability in operation.
Formation of phase composition of aluminum matrix composites during mechanical activation and self-propagating high-temperature synthesis
Authors: Prusov E S , Panfilov A A , Kechin V A
Published: August 2020

The authors investigated the effect of mechanical activation and self-propagating high-temperature synthesis (SHS) on the phase composition of composite materials of Al-TiO2-B system. It has been shown that with increasing the duration of mechanical activation of initial powders the amount of crystalline boron-containing phases in the mixture increases. X-ray diffraction analysis of powder mixtures after SHS allows making conclusion about necessity of activation for at least 45 min to obtain a target compounds. Experimental results allow reasonably choosing the modes of mechanical activation for production of aluminium matrix composites with specified composition and controllable properties.
Functional materials based on the effect of mechanoluminescence for monitoring the state of load-bearing structures
Authors: Pavlov D D , Tatmyshevskiy K V , Krylov V P
Published: August 2020

Researches of light-generating converters based on zinc sulfide allowed us to describe the physical nature of the light signal. The description of the physical nature of light generation by semiconductors is based on the band theory of conductivity. This allowed us to determine the conditions for the possibility of registering mechanical impacts using mechanoluminescent pulse pressure sensors. One of the important conditions, as it turned out, is the presence of manganese impurities in the material, which become centers of light emission. Also a necessary condition for the appearance of luminescence is the hardness of the sensor element, it facilitates the transfer of mechanical stress to the crystal lattice of mechanoluminescent material and the changes in it with the release of energy as light. This property of these materials allows them to operate in generator mode and convert mechanical action into an optical signal without additional energy sources. As a result, theoretical and experimental data on the possibility of detecting pulsed mechanical action using distributed mechanoluminescent converters were obtained. As one of the directions of application of such converters, it is proposed to create composite materials with the insertion of light-conducting fibers with longitudinal light transmission, covered with mecanoluminophore particles. This will allow to create composite materials with a self-diagnosis function and the ability to connect to optical data channels for continuous monitoring of the technical condition of load-bearing structures of buildings. Such materials are devoid of such disadvantages as: the need for power supply or a reference light stream, sensitivity to electromagnetic interference, and a low degree of embeddability in the structure, inherent in the devices currently used.
Modified heavy concrete based on activated micro-silica for sleepers of high-speed highways
Authors: Tkach E V , Temirkanov R I
Published: August 2020

A method has been developed for the synthesis of a complex additive based on ultrafine silica and superplasticizer “Plasticite RK”, which allows to obtain modified concrete with a given set of operational properties. The problem of reducing the consumption of micro-silica and increasing its efficiency in cement concretes due to chemical activation is solved. The effect of activation of microcosm in an acidic medium (pH =2.1) enriched with oxonium H3O+ ions and h+ cations is experimentally confirmed, and in an alkaline medium(pH=10-11) enriched with hydroxyl groups of OH-anions of OH-, with the production of dimers of orthosilic acid Si(OH)4, formed during chemical dispersion of microcosm are additional centers of crystallization, which concentrate new formations around themselves, forming a stable colloidal system. It has self-reinforcing processes associated with the recrystallization of colloidal size neoplasm particles into larger ones that participate in the construction of a spatial framework, which is compacted and strengthened due to prolonged hydration, contributing to an increase in the strength characteristics of cement stone and, accordingly, concrete. The use of chemical activation of micro-silica with water treated by electrolysis and enriched with hydroxyl ions OH- with pH=10-11, introduced into the matrix of the concrete mixture, in a comparative analysis showed an increase in strength by 58.8 % in comparison with the control sample of the factory composition without the use of micro-silica as part of a complex additive.
Heat conductivity of aerogel-based rolled materials for high-thermal isolation for equipment and pipelines
Authors: Pastushkov P P , Gutnikov S I , Pavlenko N V , Zheldakov D Yu , Stolyarov M D
Published: August 2020

In this article, the general information about aerogels as well as application areas of materials based on them are presented. Scientific and technical review on heat conductivity of aerogel-based thermal insulation materials was made. It was determined, that among the Russian studies the results of behaviour of these materials under high temperatures are not presented. Comprehensive studies of thermal characteristics, including heat conductivity values in temperature range of 10–650 °C (where 650 °C is the maximal operating temperature) for the thermal insulation rolled materials based on TiO2-aerogel DRT06-Z (Alison Aerogel) were carried out. The mathematical relationship between heat conductivity and operating temperature in range of 10–650 °C was determined. Using the obtained results, the calculation of thickness of insulation for the studied aerogel-based rolled materials was realized according to the construction rules SP 61.13330.2010, that can be applied for design of high-heat insulation for equipment and pipelines.
Polymer composite material for the manufacture of molds in the production of evaporative patterns
Authors: Sharshin Vladimir , Sukhorukov Denis , Sukhorukova Elena
Published: August 2020

The results of research on the development of a polymer composite material from a two-component polyurethane compound for the manufacture of foundry equipment for the production of gasified models and other products from expanded polystyrene by blowing with hot steam are presented. The requirements for the material of the molds in terms of heat capacity and thermal conductivity are indicated. Selected additives in the form of powders of copper, aluminum, iron and graphite. Samples of polymer composite materials were obtained. The research were carried out according to a specially developed technique based on the well-known method for determining thermophysical properties by eliminating variables. The result is a composition based on a polyurethane compound with 54.5 wt.% aluminum powder, meeting the specified requirements for both technological and thermophysical properties.
Effect of heat treatment of beryllium bronzes on the quality of critical engineering parts
Authors: Kartonova L , Ivanova M
Published: August 2020

The paper considers the peculiarities of thermal hardening of beryllium bronzes (Cu + 2% Be) and the feasibility of stepwise aging on BrB2 alloy parts with different requirements for their geometry. The factors determining the occurrence of stresses in beryllium bronzes parts are described. Attention is drawn to the fact that stepwise aging does not help to straighten the details as it happens during aging in special devices. Studies have shown that for cylindrical parts, when controlling deviations in straightness, stepwise aging minimizes warpage even during heat treatment without special devices. For flat parts with stringent geometry requirements, the processing of which is carried out in devices, dispersion hardening in a free state is not acceptable. For parts made of BrB2 alloy, heat treatment of which is not economically feasible in devices, but the geometry is significant, it is recommended to introduce an operation to “relieve stress” at a temperature of 210±5°C for one hour (step aging) before the operation “dispersion hardening”, that will minimize distortion during heat treatment without the use of special devices. It is shown that in each particular case, analysis is necessary on the feasibility of using staged aging, since in some cases its use can lead to a more expensive process without a significant effect in terms of reducing warpage of parts.
Physical properties of insulation materials based on straw and flax boon
Authors: Bakatovich Aliaksandr , Bakatovich Nadezhda , Mel’nikov Vladimir
Published: August 2020

Performance evaluation of environmentally friendly thermal insulation materials based on crushed straw and flax boon was determined by studying the physical parameters of thermal insulation in a climatic chamber and full-scale tests in buildings. In the climatic chamber at an air temperature of –20 °C, depending on the insulation moisture content, the thermal conductivity of the flax boon and straw slabs is 0.058 - 0.072 W/(m·°C), which is 27 - 31% lower than that of straw slabs equal to 0.08 - 0.105 W/(m·°C). With a relative air humidity of 50 - 95%, the moisture content of the flax boon and straw slabs varies within the range of 14 - 18.1% or less by 24% of the values of the crushed straw insulation. Under operating conditions, the thermal conductivity of the attic floor structure with flax boon and straw slabs corresponds to 0.07 W/(m·°C) at an air temperature of −20°C and is 22% less than the similar indicator of flooring with straw slabs equal to 0.09 W/(m·°C). A lower thermal conductivity of the floor structure with the use of flax boon and straw slabs provides an increase in temperature amplitude by 5 - 5.8 °C compared with the use of straw slabs. The results of studies in the climatic chamber and full-scale tests have confirmed the most effective operation of the flax boon and straw slabs as a thermal insulation material, which reduces energy consumption and, consequently, reduces financial costs for heating buildings.
Repair compositions based on methyl methacrylate modified with polyphenylsiloxane resin for concrete and reinforced concrete structures
Authors: Lisyatnikov M S , Roshchina S I , Chukhlanov V Yu , Ivaniuk A M
Published: August 2020

In this paper, we consider the development of repair compositions for concrete and reinforced concrete structures based on methyl methacrylate modified with polymethyl phenyl siloxane resin. The condition has been studied and the problem analyzed in the country and abroad, as well as the selection of components for the repair composition. As a binder, methyl methacrylate curable with benzoyl peroxide in the presence of a catalyst - dimethylaniline and a modifier - polymethylphenylsiloxane resin would be used. The filler was finely ground quartz sand. The operational and physicomechanical properties of the resulting compositions were studied: photoabsorption, compressive strength, and tensile strength. Experimentally, the optimal ratio of polymethylphenylsiloxane resin in the composition was found to be 2.5 mass. parts of the modifier per 100 mass. parts including a binder. It was found that the introduction of polymethylphenylsiloxane resin does not significantly affect the adhesion characteristics, the tensile strength is reduced to a small extent. Moreover, the water absorption of the cured composition with a modifier content of 3 mass. parts compared with unmodified resin is reduced four times).
Numerical solution of nonlinear integro-differential equations
Authors: Shodmonova Gulchera , Islomov Utkir , Abdisamatov Otabek , Khikmatullaev Sanjar , Kholiyorov Umirzok , Khamraeva Shakhnoza
Published: August 2020

The paper is devoted to the development of a numerical algorithm for solving nonlinear integro-differential equations based on the use of quadrature formulas. The Koltunov-Rzhanitsyn kernel with weakly singular features of the Abel type is used as a kernel. To conduct a computational experiment, a computer program was developed; the results obtained by this program are reflected in the form of tables and graphs. A test example was solved, and the obtained approximate numerical results were compared with exact solutions. The influence of nonlinearity and integral parts on the nature of oscillatory process of a viscoelastic body was investigated.
Selection and classification of various additives for monolithic concrete depending on the working conditions
Authors: Samatov M A , Cheremisin A V , Borisov A V , Chusov A N , Glinushkin A P , Zueva O A , Dolgopolov A V
Published: August 2020

The article presents the results of research on the choice of chemical additives for monolithic concrete depending on their types, main properties and applications. The working conditions are analyzed under which various monolithic concrete or monolithic reinforced concrete objects are constructed. The influence of additives on the properties of concrete and its performance characteristics is considered. The recommended calculation of the strength of concrete with additives is presented. It is shown that in the case of additives, the strength calculation should be performed using refined coefficients, mainly for the water-cement ratio. The calculation of the dosage of the additive in concrete, depending on the volume of the prepared mixture, is given. The results of an experiment with the addition of calcium nitrate to the concrete structure are presented, which confirmed an increase in the strength of the product by 20% compared to normal hardening conditions. An approximate method of selecting the most rational additives for concrete, depending on the working conditions, is given. The basis for classification of recommended additives is defined in order to ensure the required properties of concrete, taking into account the conditions of production and operation of objects using elements made of monolithic concrete.
Relaxation processes during activation of cement mixing water
Authors: Pavlov A N , Gol’Tsov Yu I , Mailyan L R , Shcherban’ E M , Stel’Makh S A
Published: August 2020

The analysis of relaxation processes in water activated thermally or ultraviolet irradiation is carried out. Activation of mixing water leads to earlier hardening of the cement. In this case, activated water loses its properties with a relaxation time that is equal to the activity time of melt water, which is explained by the general reasons for the origin of the increased reaction properties of activated water and melt water. These properties are due to the fact that upon activation, the content of free water molecules increases. In the usual state, part of the water molecules enters the voids of fractal-clathrate structures. During thermal or radiation activation processes characterized by certain relaxation times, these structures are destroyed and free water molecules are released. But after the cessation of activation, relaxation processes take place to restore thermodynamically equilibrium fractal-clathrate structures, and part of the free water is again captured by these structures. Therefore, the reactivity of water after the cessation of activation decreases.
Laser powder cladding automated control method based on advanced monitoring system of processing area by CCD-camera
Authors: Chkalov R V , Kochuev D A , Rodionov D V , Prokoshev V G , Lyukhter A B
Published: August 2020

The use of CCD cameras for recording the area of high power radiation exposure during laser cladding process is an urgent task in a view of low cost of used equipment and high information content of obtained graphic data. This approach allows real-time recognition of geometric primitives in melt pool area and based on their analysis to evaluate the quality of processing operation. The main objective of the study was to eliminate, by using external illumination, a large dynamic difference in brightness, which negatively affects the quality of images obtained. As a result of the experiments, it was found that the most effective configuration of the video recording system for laser powder surfacing process is the location of camera and illumination module against the direction of head movement. The developed illumination system for the radiation exposure area made it possible to provide conditions acceptable for the automated recognition of images obtained by the CCD camera.
Surface roughness variation in ultrasonic assisted burnishing of high-strength steels
Authors: Malygin Vladimir , Oblovatskaya Natalia , Lapteva Evgenia , Slutskov Vladimir , Shishkina Anastasia
Published: August 2020

Ultrasonic assisted burnishing process is a newly developed alternative of conventional burnishing process that enhances the surface properties of engineering materials. The process needs careful selection of design parameters to improve the quality of surface layer of workpieces made of high-strength steel that are difficult to deform. The analytical models to predict the surface roughness after the ultrasonic assisted burnishing process for surfaces are developed. Feed, ultrasonic influence power and static static force could be considered as main factors influencing to surface roughness at that feed has the greatest impact among other parameters. The models are verified by experimental studies with various ultrasonic burnishing parameters. Technological parameters of the ultrasonic burnishing are found, which decrease surface roughness from 1-2 μm to 0.05-0.55 μm. It is experimentally proved that feed increase results in surface roughness increase. To low the surface roughness of high-strength steel workpieces it is necessary to increase ultrasonic influence power with simultaneous static force lowering. The analytical models obtained in the present work may be employed in determining the best conditions for ultrasonic assisted burnishing in industrial field.
Mesoporous structure favorable for high voltage and high energy supercapacitor based on green tea waste-derived activated carbon
Authors: Gandla Dayakar , Chen Han , Tan Daniel Q
Published: August 2020

Designing high voltage, high energy, and activated carbon-based supercapacitors has been a long-time wish for meeting various electronic module requirements. This paper focuses on the approach of synthesizing the hierarchical porous activated carbon with dominant mesopores using eco-friendly green tea waste. The desirable ample pore space achieved by changing the weight ratio of KOH activating agent renders more ionic accessibility and space charge distribution. This feature leads to the achievement of 4 V double layer supercapacitor with a remarkable specific energy of 142 Wh kg−1 and specific power of 3192 W kg−1, respectively using an acetonitrile organic electrolyte. The fabricated cell also exhibits a superior 104% capacitance retention after 25 000 charge-discharge cycles at the working potential of ≥3 V. Besides, the hierarchical porous activated carbon soaked in an aqueous KOH electrolyte shows a high specific capacitance of 397 F g−1 at 5 mA cm−2, high rate capability of 100 mA cm−2, and excellent cycle life of 116% capacitance retention after 50 000 cycles tested at 200 mA cm−2. The larger Debye length of the diffuse ion layer permitted by the mesopores is proposed to explain the higher voltage window as against low voltage of micropore dominated commercial activated carbon. The present research may pave the way toward the design of high-energy supercapacitors through recycling tea waste.
Augmented Human Intelligence and Automated Diagnosis in Flow Cytometry for Hematologic Malignancies
Authors: Ng David P , Zuromski Lauren M
Published: August 2020

Objectives

Clinical flow cytometry is laborious, time-consuming, and expensive given the need for data review by highly trained personnel such as technologists and pathologists as well as the significant number of normal cases. Given these issues, automation in analysis and diagnosis holds the key to major efficiency gains. The objective was to design an automated pipeline for the diagnosis of B-cell malignancies in flow cytometry and evaluate its performance against our standard clinical diagnostic flow cytometry process.

Methods

Using 3,417 cases of peripheral blood data over 6 months from our 10-color B-cell screening tube, we used a newly described method for feature extraction and dimensionality reduction called UMAP on the raw flow cytometry data followed by random forest classification to classify cases without gating on specific population.

Results

Our automated classifier was able to achieve greater than 95% accuracy in diagnosing all B-cell malignancies, and even better performance for specific malignancies for which the panel was designed, such as chronic lymphocytic leukemia. By adjusting classifier cutoffs, 100% sensitivity could be achieved with an albeit low 14% specificity. Hypothetically, this would allow 11% of the cases to be autoverified without human intervention.

Conclusions

These results suggest that a clinical implementation of this pipeline can greatly assist in quality control, improve turnaround time, and decrease staff workloads.
Targeting 14-3-3ε activates apoptotic signaling to prevent cutaneous squamous cell carcinoma
Authors: Holmes Thomas R , Al Matouq Jenan , Holmes Matti , Sioda Natasha , Rudd Justin C , Bloom Celia , Nicola Lauren , Palermo Nicholas Y , Madson Justin G , Lovas Sándor , Hansen Laura A
Published: August 2020

More than a million cases of cutaneous squamous cell carcinoma are diagnosed in the USA each year, and its incidence is increasing. Most of these malignancies arise from premalignant lesions, providing an opportunity for intervention before malignant progression. We previously documented how cytoplasmic mislocalization of CDC25A in premalignant and malignant skin cancers confers resistance to apoptotic cell death via a mechanism that depends on its interaction with 14-3-3ε. From these data, we hypothesized that 14-3-3ε overexpression drives skin tumor development and progression, such that targeting 14-3-3ε may be a useful strategy for skin cancer treatment. Like CDC25A, 14-3-3ε was overexpressed and mislocalized to the cytoplasm of both benign and malignant human skin cancer. Skin-targeted deletion of the 14-3-3ε gene reduced skin tumor development by 75% and blocked malignant progression. 14-3-3ε suppressed apoptosis through activation of Akt, leading to inhibition of BCL2 associated agonist of cell death and upregulation of Survivin. Using virtual tetrapeptide libraries, we developed a novel peptide that specifically blocked 14-3-3ε heterodimerization and thereby prevented its interaction with CDC25A. The peptide reduced prosurvival signaling, killed skin cancer cells and reduced skin tumor growth in xenograft. Normal skin keratinocytes were unaffected by inhibition or deletion of 14-3-3ε. Thus, targeting of 14-3-3ε dimerization is a promising strategy for the treatment of premalignant skin lesions.
Decoding the Real-Time Neurobiological Properties of Incremental Semantic Interpretation
Authors: Choi Hun S , Marslen-Wilson William D , Lyu Bingjiang , Randall Billi , Tyler Lorraine K
Published: August 2020

Communication through spoken language is a central human capacity, involving a wide range of complex computations that incrementally interpret each word into meaningful sentences. However, surprisingly little is known about the spatiotemporal properties of the complex neurobiological systems that support these dynamic predictive and integrative computations. Here, we focus on prediction, a core incremental processing operation guiding the interpretation of each upcoming word with respect to its preceding context. To investigate the neurobiological basis of how semantic constraints change and evolve as each word in a sentence accumulates over time, in a spoken sentence comprehension study, we analyzed the multivariate patterns of neural activity recorded by source-localized electro/magnetoencephalography (EMEG), using computational models capturing semantic constraints derived from the prior context on each upcoming word. Our results provide insights into predictive operations subserved by different regions within a bi-hemispheric system, which over time generate, refine, and evaluate constraints on each word as it is heard.
Respiratory Illness Caused by Corynebacterium diphtheriae and C. ulcerans, and Use of Diphtheria Antitoxin in the United States, 1996–2018
Authors: Otshudiema John O , Acosta Anna M , Cassiday Pamela K , Hadler Stephen C , Hariri Susan , Tiwari Tejpratap S P
Published: August 2020

Background

Respiratory diphtheria is a toxin-mediated disease caused by Corynebacterium diphtheriae. Diphtheria-like illness, clinically indistinguishable from diphtheria, is caused by Corynebacterium ulcerans, a zoonotic bacterium that can also produce diphtheria toxin. In the United States, respiratory diphtheria is nationally notifiable: specimens from suspected cases are submitted to the Centers for Disease Control and Prevention (CDC) for species and toxin confirmation, and diphtheria antitoxin (DAT) is obtained from CDC for treatment. We summarize the epidemiology of respiratory diphtheria and diphtheria-like illness and describe DAT use during 1996–2018 in the United States.

Methods

We described respiratory diphtheria cases reported to the National Notifiable Diseases Surveillance System (NNDSS) and C. ulcerans-related diphtheria-like illness identified through specimen submissions to CDC during 1996–2018. We reviewed DAT requests from 1997 to 2018.

Results

From 1996 to 2018, 14 respiratory diphtheria cases were reported to NNDSS. Among these 14 cases, 1 was toxigenic and 3 were nontoxigenic C. diphtheriae by culture and Elek, 6 were culture-negative but polymerase chain reaction (PCR)-positive for diphtheria toxin gene, 1 was culture-positive without further testing, and the remaining 3 were either not tested or tested negative. Five cases of respiratory diphtheria-like illness caused by toxigenic C. ulcerans were identified. DAT was requested by healthcare providers for 151 suspected diphtheria cases between 1997 and 2018, with an average of 11 requests per year from 1997 to 2007, and 3 per year from 2008 to 2018.

Conclusions

Respiratory diphtheria remains rare in the United States, and requests for DAT have declined. Incidental identification of C. ulcerans-related diphtheria-like illness suggests surveillance of this condition might be warranted.
Implementing Nutrition Education Programs in Congregate Dining Service Settings: A Scoping Review
Authors: Juckett Lisa A , Lee Kathy , Bunger Alicia C , Brostow Diana P
Published: August 2020

Background and Objectives

Nutrition education programs implemented in congregate dining service (CDS) settings have the potential to improve healthy eating behaviors among older adult populations. However, little is understood about the types of nutrition education programs that are implemented at CDS sites and the factors that impede or promote implementation efforts. The purpose of this scoping review was to examine the characteristics of CDS nutrition education programs, barriers and supports to program implementation, and opportunities to enhance implementation of programming.

Research Design and Methods

We adopted a scoping review methodology to assess the relevant literature published between January 2000 and 2020 by accessing CINAHL, SocINDEX, MEDLINE, AgeLine, and Academic Search Complete.

Results

We identified 18 studies that met our inclusion criteria. The majority of nutrition education programs were led by trained facilitators, included the use of interactive activities, and also incorporated written or video materials. Programs that were adapted to the needs of older participants were perceived as supports to implementation whereas participants’ needs and resources (e.g., lack of resources and lower health literacy) were occasionally found to limit the effective implementation of programming.

Discussion and Implications

As the older adult population continues to access CDS sites to address their health and nutritional needs, purposeful efforts are needed to examine the specific approaches that can support nutrition education program implementation. Future opportunities lie in assessing strategies that are effective for mitigating barriers to implementing nutrition education programming in the CDS setting.
An automated workflow for adjoint tomography—waveform misfits and synthetic inversions for the North Island, New Zealand
Authors: Chow Bryant , Kaneko Yoshihiro , Tape Carl , Modrak Ryan , Townend John
Published: August 2020

We develop and verify an automated workflow for full-waveform tomography based on spectral element and adjoint methods. We choose the North Island, New Zealand as a study area because of its high seismicity, extensive seismic network, and the availability of a candidate ray tomography starting model. To assess the accuracy of this model, we simulated 250 regional earthquakes using a spectral element solver, and compared the resulting synthetics with recorded waveforms. In a 10–30 s passband, reasonable cross-correlation phase and amplitude misfits exist between data and synthetics, whereas at 2–30 s, waveform misalignment is severe enough that meaningful cross-correlation measurements are no longer possible. To improve the velocity model at these short periods, we created an automated inversion framework based on existing tools for signal processing, phase measurement, nonlinear optimization, and workflow management. To verify the inversion framework, we performed a realistic synthetic inversion for 3-D checkerboard structure and analyzed model recovery, misfit reduction, and waveform improvement. The results of this analysis show that the source–receiver distribution within the chosen domain is capable of resolving velocity anomalies in regions of sufficient data coverage, and of magnitudes comparable to those expected in a real seismic inversion. Along with this finding, the relative ease of use and reliability of the workflow motivates future efforts targeting a high-resolution (2–30 s), large-scale (>50 000 measurements) seismic inversion for the North Island. Updated models from such an inversion are expected to improve ground motion predictions, constrain complex velocity structures, and advance understanding of New Zealand tectonics.
Altered linkage pattern of N-glycan sialic acids in pseudomyxoma peritonei
Authors: Nummela Pirjo , Heiskanen Annamari , Kytölä Soili , Haglund Caj , Lepistö Anna , Satomaa Tero , Ristimäki Ari
Published: August 2020

Pseudomyxoma peritonei (PMP) is a highly mucinous adenocarcinoma growing in the peritoneal cavity and most commonly originating from the appendix. Glycans play an important role in carcinogenesis, and glycosylation is altered in malignant diseases, including PMP. We have previously demonstrated that fucosylation of N-glycans is increased in PMP, but we did not observe modulation of overall sialylation. As sialic acids can be attached to the rest of the glycan via α2,3- or α2,6-linkage, we have now analyzed the linkage patterns of sialic acids in tissue specimens of normal appendices, low-grade appendiceal mucinous neoplasms (LAMN), low-grade (LG) PMP and high-grade (HG) PMP. For the linkage analysis, the enzymatically released acidic N-glycans were first treated with ethyl esterification or α2,3-sialidase digestion followed by MALDI-TOF mass spectrometry. Significant increase in the relative abundance of α2,6-sialylated and decrease in α2,3-sialylated N-glycans was observed in PMP tumors as compared to the normal appendices (P < 0.025). More specifically, increased α2,6-sialylation (P < 0.05) and decreased α2,3-sialylation (P < 0.01) were detected in afucosylated and monofucosylated N-glycans of PMPs, whereas the less abundant multifucosylated glycans, containing terminal fucose, demonstrated increased α2,3-sialylation (P < 0.01). Importantly, the increase in α2,6-sialylation was also detected between PMP and the appendiceal precursor lesion LAMN (P < 0.01). The identified glycosylation alterations produce ligands for sialic acid-binding immunoglobulin-like lectins (Siglecs) and sialofucosylated glycans binding selectins, which play a role in the peritoneal dissemination and progression of the disease.