bluuebunny/crossref_metadata_2025 huggingface dataset:
Research of the issues of frequency and time support of the GLONASS system
Authors: Kartsan I N , Malanina Yu N , Zhukov A O , Klimenko A V , Tsarev R Y
Published: June 2019

The article deals with the ways of improving the accuracy of comparison of time scales of frequency and time standards in differential mode as well as the methods and algorithms for the implementation of differential comparisons of time scales of the spatially spaced highly stable o’clock. The accuracy of the location depends on many factors. With the GLONASS fully deployed orbital structure, one of the main factors determining the accuracy of obtaining the consumer coordinates is the accuracy of the navigation information transmitted as part of the navigation frame. The navigation information accuracy is determined by the state of ephemeris-time support.
Automation of oil and gas exploration by active seismic electric method
Authors: Shaydurov G Y , Potylitsyn V S , Stukach O V , Maikov O A , Romanov V V
Published: June 2019

The paper considers the issues of automation and improving the performance of the field work by the seismic electric method. It is shown that the measurement scheme used today is not optimal. It leads to a long-term deployment of the measuring installation, as well as the inability to use it in difficult geological and climatic conditions. The authors of the paper propose to use special magnetic antennas for recording the electromagnetic field, which eliminate all the drawbacks of grounded electric dipoles. It is shown that if simultaneously registering the various components of the electromagnetic field, it is possible to estimate the depth of the productive layers. The data of observations of seismic electrical effects in the gas-condensate field for various x, y, z components are given.
Evaluation of the possibility of wireless data transmission over rocks for automating an alarm system in mines using lowfrequency electromagnetic waves and radio tags
Authors: Kudinov D S , Kokhonkova E A , Maykov O A
Published: June 2019

The paper discusses the possibility of organizing a wireless data transmission channel in place of different kinds of mines for signalling and emergency communication using electromagnetic waves in the VLF propagation (300 Hz - 3 kHz). The paper gives theoretical estimates of the efficiency of propagation of electromagnetic waves in rocks and minerals with different values of electrical conductivity. The dependence of the depth of penetration on frequency is also studied. A review of the existing technical solutions to this problem is given. An analytical and numerical analysis of the current density in the rock and the magnetic field created by it using a radiating long cable is given. Reception of a signal with an informational message is carried out with the help of an individual radio tag informing personnel both in conditions of the mine’s normal operation and in emergency situations. Comparative evaluations of the efficiency of using radio tags with different configurations of a receiving antenna in mine conditions at a depth of up to 800 m are given.
Mathematical model specification of the automated control system subject based on the differential approach
Authors: Sidaras A A , Chentsov S V
Published: June 2019

This article is devoted to describing the process of mathematical model specification of an automated control system subject based on a differential approach with a help of statistical data of parameters that affect the reliability of the psychological testing results. The mathematical model of the subject is based on the fuzzy logic conclusion system, which with a greater adequacy allows to describe the subject in comparison with similar solutions, which are also based on the differential approach. There are description of the ideas and results of statistical analysis and research, the stages of the model specification process, explanations each of these stages, formulation the main provisions on the possibility of additional application of the developed mathematical model in the article.
Metric parameters of diffusion in destructive fillers automated networks
Authors: Surkov I , Ostapenko G , Belonozhkin V , Razinkin K
Published: June 2019

In this paper, a deep analysis was carried out and a classification of potentially destructive content and hazard metrics was obtained in an automated social network such as Instagram. The dependence effectiveness distribution of destructive content on the structural and functional specificity of a social network is determined. The classification of destructive content done in the Instagram social network allows us to determine the dependence popularity of various types destructive content on various parameters. The revealed dependence efficiency of the distribution of destructive content on the structural and functional specificity of a social network allows to design and implement the most effective organizational and technical measures to counteract the distribution of destructive content. Based on the above work, the owner of the automated network has the ability to influence the value of the network risk parameters in the context of the implementation of content wars.
Determination of the required degree of data protection in automated control systems
Authors: Davidyuk N V , Davidyuk V V
Published: June 2019

The article considers the specifics of automated control systems for technological production and processes as objects of information security, proposed the approach to the decomposition of their components for further evaluation of the necessary degree of protection of the data they process. The method for obtaining the quantitative assessment of the grade of information resources security is presented. The proposed method allows taking into account the data value and the degree of criticality of violations of its integrity, accessibility and confidentiality for the functioning of the system. It can be used in practice at enterprises of various kinds of activity as an independent procedure, or as part of measures at the stages of preliminary analysis of automation systems before design or improving their data protection subsystems.
Modification of ALL – SAT solver to search verification kits in testing
Authors: Lyapunova I A , Fomenko N A
Published: June 2019

To date, systems are being actively developed that imply automatic proof of software compliance with the so-called specification, i.e. requirements for it. However, in most projects, testing is still the basis of the verification process. Often this is done by people whose task is to develop tests for finding errors made by programmers in the code. Simplified tests represent a set of “input” parameters supplied to the entrance to the program, and upon completion of its work, the “output” parameters are compared with the “expected” ones according to the logic described in the specification. Testing can determine how repeated program execution with the intention of finding errors in it, but this in turn does not prove its correctness. This paper discusses the use of SAT solvers to solve the problem of finding verification kits for software testing and the development of an ALL-SAT solver modification).
Towards the advanced predictive modelling in epidemiology
Authors: Brester C , Tuomainen T P , Voutilainen A , Kauhanen J , Semenkin E , Kolehmainen M
Published: June 2019

Data-driven prediction systems used in epidemiological studies are still unsatisfactory from a practical point of view. Different pitfalls should be considered while transferring technologies from research to practice. The proposed k-Nearest Neighbors approach is designed to make disease-related predictions in a more holistic manner: we detect cases of novelty among unobserved subjects to identify situations when model predictions are not reasonably valid. Moreover, it copes with overlapping classes, finds new examples which cannot be labelled with the high confidence and reveals healthy subjects in the training data who might be at risk. Additionally, variable selection is built-in to select relevant predictors. The approach was applied to predict cardiovascular diseases based on the data collected within an ongoing follow-up study undertaken in Eastern Finland. According to the experimental results, our proposal allows increasing the accuracy of predictions made.
Automated chemiluminescent analysis of the antioxidant and prooxidant activity of natural and synthetic substrates having perspective for bioengineering
Authors: Lesovskaya M I , Shaporova Z E , Pyzhikova N I
Published: June 2019

Automated CL-control has a lot of advantages, such as rapidity, information value, objectivity, reproducibility, low-price. As a rule, the method is used for detecting antioxidant capacity of natural substrates. The results described in the paper show that this method has wide opportunities for deciding actual tasks in nutritional industry, preventive and restorative medicine, bioengineering in future. First, the results demonstrated that the method allows to determine optimal extraction conditions to obtain phytopreparates which include nonstability antioxidant and (or) prooxidant compounds. This is shown using phytopreparates (leuzea, rhodiola, rheum, plantago) obtained using local plant materials. Second, results are obtained to determine the presence of real, non-virtual antioxidant or prooxidant properties of commercial micronutrients complexes. In addition, the method allows to provide an individual selection of nutrients in accordance with the characteristics of the ROS balance of the internal environment of the consumer’s body. This way allows to get the reproducible results within a relevant experimental model in short time, which is very important looking for dynamic development of the functional nutrients market. Finally, using this method one get more effective and economic navigation of chemical synthesis. As a result, the efficiency of the subsequent functionalization of synthetic compounds is increased.
Mathematical modelling of pore formation in polymers using supercritical fluid media in the Ornstein-Zernike approximation
Authors: Gil’mutdinov I M , Kuznetsova I V , Gil’mutdinov I I , Sabirzyanov A N
Published: June 2019

The paper studies the process of pore formation using supercritical fluid media. A mathematical model of pore formation in polymers in the process of supercritical carbon dioxide decompression has been developed, taking into account fluctuations in the Ornstein-Zernike approximation based on Patel-Teja cubic equation. Calculations and comparison with experimental data are given on the example of pore formation in polystyrene, which showed satisfactory agreement of the theory with experiment. Parameters of the Lennard-Jones pair interaction potential for carbon dioxide in the carbon dioxide-polystyrene system were obtained. The diffusion coefficient of supercritical carbon dioxide in a polymer takes on a different value than the coefficient of self-diffusion of pure carbon dioxide under the same thermodynamic conditions due to a change in the Lenard-Jones potential profile in a polymeric medium. The obtained values of the parameters of the Lennard-Jones equation, namely, the parameters of the intermolecular interaction potential and the maximum value of the attraction energy, make it possible to adequately estimate the value of the diffusion coefficient under given thermodynamic conditions.
Development and justification of the treatment system layout scheme for dust emissions from mobile and portable asphaltconcrete plants
Authors: Sidyakin P A , Khorzova L I , Borovkov D P , Klimenti N Yu
Published: June 2019

Nowadays, reducing the amount of dust in urban atmosphere is an urgent task for the majority of industrially advanced countries in the world. Road construction works are one of the factors influencing the increase in the dust particles concentration in the atmospheric air. The authors present the treatment schemes for dust emissions from mobile and portable asphalt concrete plants applying dust collectors with countercurrent swirling flows. They conducted an analytical investigation of the operation of the designed layout schemes applying dust collectors with countercurrent swirling flows (CSF), dust concentrators and bag filters. The justification of the optimum layout scheme was presented.
Monitoring of aerial technogenic zone of influence of the production facility as a tool of ecological engineering
Authors: Krupina N N , Kipriyanova E N , Medyanik N V , Smirnova V O
Published: June 2019

The actuality of the extended research of spatial factor of formation of the territory of the maximum long-term air pollution, as a prerequisite of health risks to residents in industrial cities and the corresponding indicator is specified. Due to the heterogeneity of the dispersion conditions, the real boundaries of the zones of negative impact of emission sources turn out to be more controllable, and due to the overlapping and layering of contamination fields, the concentration of impurities may exceed the norms. It was proposed to correct the known index of the ratio of the industrial site area and the pollution zone and use it to calculate the average annual area of the such fields, taking into account key meteorological parameters. Recommended correction factors that characterize the proportion of polluted urban areas, highlighted the key elements of the industrial hub as objects of environmental engineering and specified the direction of search for organizational and technical solutions.
Analysis of thermophysical properties of cooling elements
Authors: Marushin L A , Tikhonova D A
Published: June 2019

The essence of the study is to analyse thermophysical properties of cooling elements of electronic equipment. For optimal selection of structural materials and effective cooling of working surfaces, authors carried out numerical studies of the elements based on cadmium selenide, gallium arsenide, indium phosphide, etc.
Digital contour of linear control in the pulse voltage stabilizer
Authors: Titovskii S N , Titovskaia T S , Titovskaia N V , Shaporova Z E
Published: June 2019

This paper provides an analysis of the operation of the pulse voltage stabilizer with a digital control contour, which uses a linear dependence between power switch opening pulse duration and the output voltage deviation from the nominal one. The influence of the errors, caused by digital data representation, on the control loop output impulse duration was evaluated. The conditions that minimize the influence of these errors on the stabilizer operation are revealed.
Application of a systematic approach to improving the efficiency of power supply modes of the Republic of Crimea
Authors: Vologdin S V , Yakimovich B A
Published: June 2019

The structure of the region’s energy supply is considered, the characteristics of all the major groups of electricity producers in the region, including thermal power plants, mobile gas turbine power plants, renewable energy sources, backup power sources, are presented. As tariffs in the transport problem under consideration, depending on the purpose of the calculations, it is proposed to use the averaged actual values in a given period of time according to the energy supplying organizations (the purpose of the calculations is to reduce the cost of production and transportation of electricity), and also conditional qualitative assessments - “fines” (The goal is to improve the environmental and reliability of the system as a whole). The influence of the generated power of solar power plants on the operation modes of the power system of the Crimea is investigated. A methodology has been developed to optimize the production of solar power plants that affect the reliability and quality of power supply. The calculation of different scenarios of energy supply of the Crimea carried out, including at peak and average modes of power consumption, with different variants of solar activity, the time of year, taking into account and without taking into account the energy sources under construction, repair works of sources in the off-season. Based on the results of the calculations, conclusions are made about the reliability of the power system in the region under different scenarios of power supply, as well as the need to use the power bridge for the flow of electricity from the mainland in both directions.
On the implementation of the ecological approach in the process of territories demilitarization
Authors: Gerasimova L A , Eremina I Yu , Kuklina A I
Published: June 2019

Ensuring environmental safety in the areas of rocketry operation is associated with an assessment of the natural environment response to the transient effects of chemically hazardous substances. The object of the research was Scotch pine as a bioindicator of pollution of the soil from the storage area of rocket fuel components (RFC). Infection of the needles with chlorosis and necrosis can characterize the level of soil pollution with toxic components. For soil reclamation, it is recommended to carry out a microbiological analysis of the soil and make a detailed map of phytotoxicity to calculate the volume and technology of work. When making a phytotoxicity map, it is recommended to take into account the percentage and quality ratio of needles samples subject to necrosis and chlorosis.
Application of hydrobiological analysis for improving the efficiency of water treatment
Authors: Ponomareva Yu A , Andrianova A V
Published: June 2019

The study was conducted on the open water intake Gremyachiy Log. A period of tighten control at all stages of water treatment was established according to the turbidity of natural water and the quantitative content of algae. It was found that diatoms form the basis of the floristic list in the Yenisei River (66% of the total species composition), they prevail in plankton in all seasons of the year. The patterns of phytoplankton development and its influence on the operation of water intake structures were revealed. The possibilities of optimizing the operation of the Gremyachy Log water intake filtering and treatment facilities by controlling the amount of reagents, used in water treatment, and controlling technological processes, were considered.
Modeling and system analysis of drinking water parameters in urban water supply systems
Authors: Isakov V G , Vologdin S V , Ponomarev D S , Dyagelev M Y
Published: June 2019

The article discusses the use of mathematical modeling and system analysis methods to solve problems of water preparation. Models for predicting indicators of drinking water based on the quality of the source water are proposed. The technological process of deodorization of drinking water is considered. The following system analysis methods were used in the models development: correlation analysis of data, the principal component method, regression modeling, and the least squares method. Hidden relationships between indicators of drinking and source water were identified. The adequacy of the obtained results was proved by comparing them with the actual values. The obtained results approximate well the actual values. The results can be used in water supply systems to improve the quality of drinking water.
Analysis of the state of the fuel market of the Russian Federation and its development prospec
Authors: Bezborodov Yu N , Shram V G , Vereshchagin V I , Sokolnikov A N , Kovaleva M A
Published: June 2019

The article presents an analysis of the state of the Russian fuel market, discusses the quality of fuels and their impact on the environmental situation in large cities, as well as the prospects for the development of the fuel market. The constraints and competitive advantages of transport to gas engine fuel are described. It has been established that the development of the market requires not only the creation of a developed infrastructure and the improvement of gas utilization technologies, but there is also a need to improve legislation in the fuel industry in order to create effective mechanisms for its state regulation.
The elaboration of environmentally safe way of galvanic sludge deactivation with the use of bentonite clay
Authors: Mostalygina L V , Elizarova S N , Kostin A V , Mostalygin A G
Published: June 2019

On the basis of experimental data, the qualitative galvanic sludge composition has been got after reactant purification of waste water of the machine building enterprise. The research has been carried out on the degree of incapsulation of heavy metals in the system of galvanic sludge (GS) – cement-sand (CS) – bentonite clay (BC) with different percentage ratio of components. It has been stated that it took 28 days to complicate galvanic sludge with the mixture of CS and CS-BC. It has been shown that appending of 5% and 10% bentonite clay into the system GS-CS increases its sorption capacity and leads to decrease of washing heavy metals out of it. It has been defined that initial heat treatment of galvanic sludge with subsequent appending of BC ensures decrease of concentration of chromium ions, cuprum and ferrum in the water which is lower than the level of admissible concentration limit (ACL).
Detection of changes in urban environment based on infrared satellite data
Authors: Gosteva A A , Matuzko A K , Yakubailik O E
Published: June 2019

Changes in the microclimate of the urban environment often occur as a result of changes in urban development, artificial changes in the relief, and the cutting down of forest plantations. Due to changes in the urban environment there is a change in the microclimate of the city, which entails a direct change in the land surface temperature. Changes in the urban environment can be detected using space images of different spatial resolution in the visible and far infrared range. Landsat data is currently the most accessible, complete, and open for studying these changes. Thermal imaging is widely used for monitoring urban sites. To increase the spatial resolution, synthesis of Landsat-8 images with higher spatial resolution images of Planet Scope is used, which allows increasing the spatial resolution of surface temperature maps produced from Landsat-8 images from 30 meters to 3 meters. The paper presents the results of an assessment of the land surface temperature in the city of Krasnoyarsk for a two-year period from September 2016 to September 2018 based on the analysis of Landsat-8 and Planet Scope satellite images.
Environmental engineering as a tool to reduce the risks of industrial production in the region
Authors: Afanasieva Elena , Koreva Olga , Tikhii Vladimir
Published: June 2019

This article proves that one of the main conditions of overcoming technological inferiority and improving the competitiveness of the territory is a balanced socio-economic development of the region which should be planned with consideration of reducing the negative impact of industry on the environment on the basis of industrial areas rational placement, the use of resource-saving technologies and alternative energy sources. This article presents a SWOT analysis of the investment project of the industrial enterprise for the production of floor coverings from polyvinylchloride (PVC) being implemented in the Orel region. The authors of the study identified the environmental risks of launching this production. It has been discovered that it will have a negative impact on the environment. One of the effective tools to reduce environmental risks and to ensure environmental safety in the industrial enterprise is environmental engineering. Some specific measures for the industrial enterprise environmental audit for the production of floor coverings from polyvinylchloride (PVC) in the Orel region have been proposed.
The impact of cavitation-activated water on combustion dynamics and environmental characteristics of coal-water slurry fuel
Authors: Stebeleva O P , Kashkina L V , Petrakovskaya E A , Nikitin S L , Valiullin T R
Published: June 2019

Among the new coal technologies the burning of low-grade coal in the form of coal-water slurry fuel (CWSF) is of a great interest. The basis of CWSF is a highly concentrated coal-water slurry consisting of finely ground coal, water or other liquid and plasticizing agents. The development of CWSF technology is highly relevant for solving global problems of resource conservation and ecology. The study is dedicated to CWSF properties with respect to Kansk-Achinsk coal and water. This paper presents the results of the influence of CWSF’s preliminary cavitation water treatment on the combustion dynamics of fuel, (including the features of the combustion temperature trends, delayed ignition time and time of complete combustion) and on its environmental characteristics. A rotary-type hydrodynamic oscillator at high angular velocity (10000 rpm) was used in supercavitation mode. It is shown that the technology of cavitation water treatment leads to a change in the dynamics of CWSF’s combustion and to an additional decrease in NOx emissions by 1.6 times, CO2 by 1.3 times.
Energy economy potential estimation of establishment needs objects of power distribution company
Authors: Saprykin A I , Sizganova E J
Published: June 2019

This article describes a systematic approach in assessing the potential of energy saving, based on the universal model of technocenosis. A rank analysis of retrospective data on energy consumption was carried out, a mathematical model of power consumption was obtained. The procedures of interval estimation of the rank parametric distribution are carried out and the objects of establishment needs are determined, which power consumption is not included in the boundaries of statistical norms. With the help of cluster procedures, technocenological norms of power consumption are calculated. Based on the theory of structural and topological dynamics of the rank parametric distribution, the predicted power consumption is determined. The energy saving potential has been calculated and the objects of economic needs have been identified, where the implementation of measures aimed at energy saving is first necessary.
Research results of makeup influence on semi-synthetic motor oils thermal oxidation stability
Authors: Agrovichenko Daria V , Kovalsky Boleslav I , Bezborodov Yury N
Published: June 2019

During the running motor oil quality determination oil makeup has a big influence on thermal oxidation mechanism, however there is a problem of insufficient examination of makeup influence on motor oil conditions. Main goal of these researches is to determine how makeup effects on motor oil’s thermal oxidation stability. For the research Lube oil Lukoil Super 10W - 40 SG/CD has been chosen. Thermal oxidation stability results assessment was conducted basing on obtained values of: light stream absorption criteria, volatility and thermal oxidation stability criteria in cases of research with makeup and without it. There was offered a criteria of makeup influence on thermal oxidation stability values, which identified as change of light stream absorption rate proportion and thermal oxidation stability criteria in case of research with and without makeup. Research methodology involved motor oil test on thermostating device consequently under temperatures 180, 170 and 160 °C with makeup and without it in condition when quantity of makeup oil corresponded to vaporized oil quantity. Research results demonstrated that oil makeup decrease thermal oxidation intensity on the whole temperature test rate.
Analysis of climatic characteristics of the territory of distribution of the Siberian silk moth
Authors: Dergunov A V , Yakubailik O E
Published: June 2019

Siberian silk moth is one of the most dangerous pests of coniferous forests of Krasnoyarsk region, which are the most important natural resource of the region. Climate change is considered to be one of the essential criteria for the growth of the silk moth population. In 2014, there was another outbreak of the number of silk moth in the Yenisei district of Krasnoyarsk region. It is known that the forest area of the Yenisei river left bank is subject to severe damage by the silk moth, and the right bank is characterized by a weak forest damage. The task of this work is to analyze the situation with the heterogeneous lesion of the forest by the Siberian silkworm on both banks of the Yenisei river of the territory under consideration according to most detailed available meteorological data for the period from 2009 to 2018. The results of the study showed that the left bank of the river has an increased surface temperature compared to the right bank by an average of 1-1.5°C during the period under review. This effect may be the reason for the spatial distribution of the Siberian silk moth population.
Modeling of the milling process dynamics of the fibrous semiproducts
Authors: Pen V R , Stupina A A , Levchenko S I , Panfilov I A , Pen T V
Published: June 2019

Presentation of the milling as mechanochemical process allows to present a mathematical model based on the principals of formal kinetics that forms a complete mathematical description of the dynamics of the milling of fibrous semiproducts.
Experimental determination of freeze-thaw resistance in self-compacting concretes
Authors: Kocáb D , Lišovský M , Žítt P
Published: June 2019

The paper describes the determination of freeze-thaw resistance in self-compacting concretes and compares several test methods used for this purpose. The basic principle of testing freeze-thaw resistance is the observation of changes, in this case the loss of certain properties, in concrete attacked by freeze-thaw cycles. This paper documents measurements of tensile strength, tensile splitting strength, and dynamic Young’s modulus measured by the ultrasonic pulse velocity test and resonance method. The outcome of the experiment is an evaluation of how suitable each test is for determining the freeze-thaw resistance of self-compacting concrete.
Acid attack on hardened cement paste by acids forming low soluble calcium salts
Authors: Pavlík V
Published: June 2019

Solutions of acids have very aggressive effect on the cement matrix in concrete. Aggressiveness of the solutions increases with concentration of an acid but also depends on the acid type. The corrosion effect of solutions of various types of acids and their mixtures on hardened cement pastes is described in the paper. The results confirmed, that the rate of corrosion of hardened cement paste in solutions of strong acids (HCl, HNO3) was faster than in solutions of weak acids. However, the rate of corrosion of hardened cement paste was lower in solutions of acids that produce low soluble calcium salts, because calcium salts filled the pores in the layer of corrosion products and thus increased its diffusion resistance.
Usability of waste perlite in the technology of production of autoclaved aerated concrete
Authors: Hustavova J , Sebestova P , Meszarosova L , Cerny V , Drochytka R
Published: June 2019

The building industry constantly seeks ecological solutions and accents utilization of industrial wastes. For this reason, even less examined alternatives are considered. This is true also for manufacture of autoclaved aerated concrete. This paper addresses usability of waste perlite in the technology of production of autoclaved aerated concrete. Waste perlite has been examined to great extent in particular in the area of cement based composite materials, where its positive influence is known. This leads to the idea of finding out if waste perlite could contribute positively to the technology of autoclaved aerated concrete. In this basic research, four replacement amounts of quartz sand with waste perlite were tested: 10%, 30%, 50% and 100%. Replacement of 30% appears to be most promising. At this amount, the compressive strength increased and at the same time, volume weight was reduced by 40%.
Influence of biopolymeric water-retaining admixtures on hydration of Portland cement studied using isothermal calorimetry
Authors: Žižlavský T , Vyšvařil M , Rovnaníková P
Published: June 2019

Viscosity enhancing and water-retaining admixtures based on the cellulose ethers are widely used in the building industry to improve the properties of concrete and ready-mix mortars. The study focuses on the influence of the alternative natural viscosity enhancing admixtures (sodium salt of alginic acid, carrageenan, diutan gum, xanthan gum, and hydroxypropyl derivatives of guar gum and chitosan) in doses of 0.1%, 0.5%, and 1% of the binder weight on the cement hydration. The study is carried out using isothermal calorimetry studying the heat flow and the total heat evolved during the reaction from the very beginning – the water-introduction into system. All of the studied biopolymers showed the set retarding ability as they are all of polysaccharidic origin. The dosage-dependency was significant for the hydroxypropyl guaran and diutan gum, while retarding effect of other admixtures varied only slightly with the amount of biopolymer in the studied range of doses. However the studied admixtures were less effective in the delay of accelerating period, as well as the reduction of total heat generated during the reaction, in comparison with cellulose ethers. Other admixture than hydroxypropyl guar gum or diutan gum should be chosen if the set-retarding ability is not appropriate for the mixture use, otherwise the advantage over cellulose ethers will not be significant.
Comparative effectiveness of sitagliptin vs sulphonylureas in older people
Authors: Sharma Manuj , Nazareth Irwin , Petersen Irene
Published: June 2019

Background

two common anti-diabetic treatments used are sitagliptin and sulphonylureas however evidence examining their comparative effectiveness in older people is limited.

Objective

to evaluate effectiveness of sitagliptin vs sulphonylureas when added to metformin in older (aged ≥75) vs younger people (18–75).

Design

retrospective cohort study.

Setting

UK Primary Care.

Subjects

2,904 individuals prescribed sitagliptin (223 aged≥75) and 13,683 prescribed sulphonylureas (1,725 aged ≥75).

Methods

multivariable regression to analyse difference in HbA1c and weight, 12 months after add-on initiation and proportion achieving different glycaemic targets.

Results

after multivariate adjustment to remove baseline differences, the HbA1c after 12 months of treatment was on average 1 mmol/mol (95%CI −0.7 to 2.8) higher with sitagliptin vs sulphonylureas in older people though this was not statistically significant. The weight however, was significantly lower −1.4 kg (95%CI −2.1 to −0.7) with sitagliptin vs sulphonylureas. A lower proportion prescribed sitagliptin vs sulphonylureas recorded HbA1c < 48 mmol/mol by study end: Odds Ratio 0.63 (95%CI 0.42–0.95). In younger people, similar HbA1c reductions were also observed with both treatments, however weight after 12 months was even lower with sitagliptin vs sulphonylureas: −2.3 kg (95%CI −2.5 to −2.0).

Conclusions

similar HbA1c reduction was observed when sitagliptin or sulphonylureas were added to metformin in older and younger age-groups. Sitagliptin use led to modest comparative weight loss. There may be greater risk of over-treatment with sulphonylureas evidenced by greater proportion recording HbA1c < 48 mmol/mol by study end. This evidence supporting use of sitagliptin when add-on therapy is selected in older adults should be considered alongside the wider evidence-base and patient-preference.
Armed Conflicts and Food Insecurity: Evidence from Boko Haram's Attacks
Authors: George Justin , Adelaja Adesoji , Weatherspoon Dave
Published: June 2019

More than half of the 815 million undernourished people in the world live in countries struggling with conflict, violence and fragility. Conflict can impact food security conditions by destroying agricultural production, distribution and markets, hindering economic growth and increasing unemployment levels. By spatially joining the general household survey (GHS) panel data for Nigeria with Boko Haram terrorist incident data, we estimate the impact of Boko Haram attacks on food security conditions. We find that an increase in conflict intensity, measured by number of fatalities, increases the number of days where the household had to (1) rely on less preferred foods, (2) limit the variety of foods eaten, and (3) limit the portion size of meals consumed. However, the number of days that households went without eating anything, a more severe measure of food insecurity, was not affected. The food consumption score is also negatively affected by conflict. We also find that the conflict‐driven food insecurity is mainly materialized through agricultural input and income shocks.
The Impact of Technology on the Diagnosis of Congenital Malformations
Authors: Straub Loreen , Huybrechts Krista F , Bateman Brian T , Mogun Helen , Gray Kathryn J , Holmes Lewis B , Hernandez-Diaz Sonia
Published: June 2019

As technology improves and becomes more widely accessible, more subclinical congenital malformations are being detected. Using a cohort of 1,780,156 pregnant women and their offspring nested in the 2000–2013 US Medicaid Analytic eXtract, we contrasted time trends in malformations which do not necessarily present with overt clinical symptoms early in life and are more likely to be diagnosed via imaging (secundum atrial septal defect, patent ductus arteriosus, ventricular septal defect, pulmonary artery anomalies, pulmonary valve stenosis, hydrocephalus) with trends in malformations that are unlikely to escape clinical diagnosis (tetralogy of Fallot, coarctation of the aorta, transposition of the great vessels, hypoplastic left heart syndrome, oral cleft, abdominal wall defect). Logistic regression was used to account for trends in risk factors while assessing the impact of increased screening intensity. Prevalence of the diagnosis of secundum atrial septal defect rose from 2.3‰ in 2000–2001 to 7.5‰ in 2012–2013, of patent ductus arteriosus from 1.9‰ to 4.1‰, and of ventricular septal defect from 3.6‰ to 4.5‰. Trends were not explained by changes in the prevalence of risk factors but were attenuated when accounting for screening tests. The other malformations showed no temporal trends. Findings suggest that increased screening partially explains the observed increase in diagnosis of milder cases of select common malformations.
A Birth Cohort Study about the Genetic Modification of Prenatal Methylmercury Association with Child Cognitive Development
Authors: Julvez Jordi , Smith George Davey , Ring Susan , Grandjean Philippe
Published: June 2019

Genetic predisposition may affect neurodevelopmental outcomes of prenatal methylmercury exposure. We examined suspected heterogeneities for modification of exposure-related neurodevelopment in children from the Avon Longitudinal Study of Parents and Children (ALSPAC, 1991-2000), Bristol, United Kingdom. A subgroup (n = 1127 from a pilot study and 1045 from the present study) was identified based on the availability of the mercury concentration of cord tissue as a measure of prenatal methylmercury exposure, data on 247 single-nucleotide polymorphisms (SNPs), as well as the Wechsler Intelligence Scale for Children Intelligence Quotient (IQ) scores. Log10-transformed mercury concentration was positively associated with IQ, but adjustment confounding cofactors attenuated this association. Enhanced interaction with methylmercury was replicated in the new study for the minor allele of rs1042838 (progesterone receptor) (Beta; 95% Confidence Interval) = (-11.8; -23.0, -0.6) (P-for-interaction = 0.004) and weakly for rs662 (paraoxonase 1) (-3.6; -11.4, 4.3) (P = 0.117). In the joint sample, new interacting single-nucleotide polymorphisms (SNPs) were discovered in relation to superoxide dismutase 2, ATP binding cassette subfamily A member 1, and metallothionein 1M genes. While the low-level prenatal exposure to methylmercury was not associated with child cognition, progesterone receptor rs1042838 minor alleles revealed a negative association of mercury exposure with IQ.
Prognostic Significance of Pulse Pressure and Other Blood Pressure Components for Coronary Artery Disease in Type 1 Diabetes
Authors: Guo Jingchuan , Muldoon Matthew F , Brooks Maria M , Orchard Trevor J , Costacou Tina
Published: June 2019

BACKGROUND

To compare in individuals with type 1 diabetes the prediction of incident coronary artery disease (CAD) by components of resting blood pressure—systolic, diastolic, pulse pressure, and mean arterial pressure.

METHODS

In 605 participants without known CAD at baseline and followed sequentially for 25 years, we used Cox modeling built for each blood pressure component associated with incident CAD, overall and stratified by age (<35 and ≥35 years) or hemoglobin A1c (HbA1c) (<9% and ≥9%).

RESULTS

Baseline mean age and diabetes duration were 27 and 19 years, respectively. We observed an early asymptote and then fall in diastolic blood pressure in their late 30s and early 40s in this group of type 1 diabetes individuals, followed by an early rise of pulse pressure. Adjusted hazard ratios (HR) (95% con) for CAD associated with 1 SD pressure increase were 1.35 (1.17, 1.56) for systolic pressure; 1.30 (1.12, 1.51) for diastolic pressure; 1.20 (1.03, 1.39) for pulse pressure; and 1.35 (1.17, 1.56) for mean arterial pressure. Pulse pressure emerged as a strong predictor of CAD at age ≥ 35 years (HR: 1.49 [1.15, 1.94]) and for HbA1c ≥ 9% (HR: 1.32 [1.01, 1.72]).

CONCLUSIONS

Individuals with type 1 diabetes may manifest early vascular aging by an early decline in diastolic blood pressure and rise in pulse pressure, the latter parameter becoming a comparable to systolic blood pressure in predictor incident CAD in those aged over 35 years and those with poor glycemic control.
Impact of a chemotherapy workload and productivity dashboard on pharmacy technician turnover
Authors: Trinh Long D , Wong Jason T , Sullivan Patricia A , Nguyen Lam H , Pham Yen T
Published: June 2019

Purpose

To describe the methods used in the development of an intravenous chemotherapy workload and productivity dashboard and its impact on symptoms of burnout and technician turnover.

In February 2017, chemotherapy sterile preparation pharmacy technicians reported symptoms of burnout as a result of perceived increase in workload. In response, an i.v. chemotherapy workload and productivity dashboard was developed at an academic medical center to validate workload in comparison to the reported job stress of pharmacy technicians. The dashboard provided pharmacy leadership objective data to validate staff concerns and leveraged lean principles to level-load the work prior to requesting additional full-time equivalents (FTEs) to senior leadership. The rate of turnover of i.v. chemotherapy technicians was assessed before (December 2016–June 2017) and after (July 2017–January 2018) dashboard implementation and approval of an additional i.v. chemotherapy technician FTE. The addition of the new FTE resulted in a decrease in productivity from an average of 106% (range 67%–151%) to 84% (range 65%–110%). The interventions allowed for the ability to leverage a staffing-to-demand model, resulting in the observed improvement in technician symptoms of burnout and a notable decrease in the overall turnover rate of i.v. chemotherapy technicians.

Conclusion

The i.v. chemotherapy workload and productivity dashboard confirmed frontline staff perception and provided data to support the addition of labor resource and an opportunity to leverage a staffing-to-demand model to decrease symptoms of burnout and technician turnover.
Beware the Jaccard: the choice of similarity measure is important and non-trivial in genomic colocalisation analysis
Authors: Salvatore Stefania , Dagestad Rand Knut , Grytten Ivar , Ferkingstad Egil , Domanska Diana , Holden Lars , Gheorghe Marius , Mathelier Anthony , Glad Ingrid , Kjetil Sandve Geir
Published: June 2019

The generation and systematic collection of genome-wide data is ever-increasing. This vast amount of data has enabled researchers to study relations between a variety of genomic and epigenomic features, including genetic variation, gene regulation and phenotypic traits. Such relations are typically investigated by comparatively assessing genomic co-occurrence. Technically, this corresponds to assessing the similarity of pairs of genome-wide binary vectors. A variety of similarity measures have been proposed for this problem in other fields like ecology. However, while several of these measures have been employed for assessing genomic co-occurrence, their appropriateness for the genomic setting has never been investigated. We show that the choice of similarity measure may strongly influence results and propose two alternative modelling assumptions that can be used to guide this choice. On both simulated and real genomic data, the Jaccard index is strongly altered by dataset size and should be used with caution. The Forbes coefficient (fold change) and tetrachoric correlation are less influenced by dataset size, but one should be aware of increased variance for small datasets.

All results on simulated and real data can be inspected and reproduced at https://hyperbrowser.uio.no/sim-measure.
OncodriveCLUSTL: a sequence-based clustering method to identify cancer drivers
Authors: Arnedo-Pac Claudia , Mularoni Loris , Muiños Ferran , Gonzalez-Perez Abel , Lopez-Bigas Nuria
Published: June 2019

Motivation

Identification of the genomic alterations driving tumorigenesis is one of the main goals in oncogenomics research. Given the evolutionary principles of cancer development, computational methods that detect signals of positive selection in the pattern of tumor mutations have been effectively applied in the search for cancer genes. One of these signals is the abnormal clustering of mutations, which has been shown to be complementary to other signals in the detection of driver genes.

Results

We have developed OncodriveCLUSTL, a new sequence-based clustering algorithm to detect significant clustering signals across genomic regions. OncodriveCLUSTL is based on a local background model derived from the simulation of mutations accounting for the composition of tri- or penta-nucleotide context substitutions observed in the cohort under study. Our method can identify known clusters and bona-fide cancer drivers across cohorts of tumor whole-exomes, outperforming the existing OncodriveCLUST algorithm and complementing other methods based on different signals of positive selection. Our results indicate that OncodriveCLUSTL can be applied to the analysis of non-coding genomic elements and non-human mutations data.

Availability and implementation

OncodriveCLUSTL is available as an installable Python 3.5 package. The source code and running examples are freely available at https://bitbucket.org/bbglab/oncodriveclustl under GNU Affero General Public License.

Supplementary information

Supplementary data are available at Bioinformatics online.