51 research outputs found
Algorithms of Multifactorial Regression Modeling in Ecological and Hygienic Studies
Introduction. One of the most urgent problems of environmental health is soil contamination by oil and petroleum products (PP) and its impact on crop productivity and population health. The main task here is to determine the acceptable or safe concentrations of PP in the
soil. However, at present time there is no unified approach of PP regulating in different countries. One possible solution of the problem is mathematical modeling of the results of experimental studies. With the help of mathematical models, it becomes possible not only to
describe the investigated dependencies, but also to calculate safe levels of PP in the soil. The purpose of the paper is to develop a methodology for constructing and using multifactor nonlinear regression models from data obtained in a real ecological and biological experiment. Results. The article presents the results of an experimental study of the influence of one type ofpetroleum products — diesel fuel, when it enters the soil to germinate one of the most
important crops — wheat. It is shown that the mathematical model describing the suppres sion of wheat growth should be a multifactorial function ("time — concentration — effect"),
which has a nonlinear character. An algorithm for constructing multifactorial nonlinear regression models is proposed. On the basis of experimental data, an adequate multifactor nonlinear mathematical model was developed. This made it possible to calculate the thresh old concentration of diesel fuel, which does not affect the growth of wheat. Conclusion. On the basis of the proposed algorithm from experimental data an adequate multifactor nonlinear regression model was constructed. With the help of this model, the concentration of diesel fuel that does not cause a negative effect on the growth of wheat was calculated
Algorithms of Multifactorial Regression Modeling in Ecological and Hygienic Studies
Introduction. One of the most urgent problems of environmental health is soil contamination by oil and petroleum products (PP) and its impact on crop productivity and population health. The main task here is to determine the acceptable or safe concentrations of PP in the soil. However, at present time there is no unified approach of PP regulating in different countries. One possible solution of the problem is mathematical modeling of the results of experimental studies. With the help of mathematical models, it becomes possible not only to describe the investigated dependencies, but also to calculate safe levels of PP in the soil. The purpose of the paper is to develop a methodology for constructing and using multifactor nonlinear regression models from data obtained in a real ecological and biological experiment. Results. The article presents the results of an experimental study of the influence of one type of petroleum products — diesel fuel, when it enters the soil to germinate one of the most important crops — wheat. It is shown that the mathematical model describing the suppres sion of wheat growth should be a multifactorial function ("time — concentration — effect"), which has a nonlinear character. An algorithm for constructing multifactorial nonlinear regression models is proposed. On the basis of experimental data, an adequate multifactor nonlinear mathematical model was developed. This made it possible to calculate the threshold concentration of diesel fuel, which does not affect the growth of wheat. Conclusion. On the basis of the proposed algorithm from experimental data an adequate multifactor nonlinear regression model was constructed. With the help of this model, the concentration of diesel fuel that does not cause a negative effect on the growth of wheat was calculated.Предложен алгоритм построения многофакторных нелинейных регрессионных моделей, состоящий из иерархически организованных этапов: графического анализа, выбора вида частных математических моделей, численного расчета их параметров и последующей свертки в общую математическую модель. Представлены результаты экспериментального исследования влияния одного из видов нефтепродуктов — дизельного топлива, при его попадании в почву на всхожесть важнейшей сельскохозяйственной культуры — пшеницы. Показано, что математическая модель, описывающая процесс угнетения роста пшеницы, должна представлять собой многофакторную функцию («время — воздействие — эффект»), имеющую нелинейный характер. Разработан и представлен алгоритм расчета параметров многофакторной нелинейной функции. По експериментальным данным на основе предложенного алгоритма была построена адекватная многофакторная нелинейная математическая модель и рассчитаны все ее параметры. С ее помощью установлена пороговая величина концентрации дизельного топлива, не влияющая на всхожесть пшеницы.Запропоновано алгоритм побудови багатофакторних нелінійних регресійних моделей, який складається з ієрархічно організованих етапів: графічного аналізу, вибору виду часткових математичних моделей, чисельного розрахунку їх параметрів і подальшої згортки в загальну математичну модель. Представлено результати експериментального дослідження впливу на схожість найважливішої сільськогосподарської культури — пшениці, одного з видів нафтопродуктів (дизельного палива) за умови його попадання у грунт. Показано, що математична модель, яка описує процес пригнічення росту пшениці, повинна бути багатофакторною функцією («час — вплив — ефект»), що має нелінійний характер. Розроблено та наведено алгоритм розрахунку параметрів для багатофакторної нелінійної функції. За експериментальними даними на основі запропонованого алгоритму було побудовано адекватну багатофакторну нелінійну математичну модель і розраховано всі її параметри. За її допомоги встановлено порогову величину концентрації дизельного палива, яка не впливає на схожість пшениці
Noise-protective properties of green plantations on urban territories
Впервые дана акустическая характеристика насаждений города Уфа, выявлены закономерности изменения уровня шума в зависимости от типа насаждения.
For the first time the acoustic characteristic of plantings of the city of Ufa is given, regularities of change of noise level depending on planting type are revealed
Environmental impact assessment activities of mining and processing enterprises of the South Urals on a grassy, treekostenoglou and woody vegetation
В статье приведен анализ экологических последствий наносимых горно-обогатительными комбинатами Южного Урала на травянистую, древесно-кустарниковую и древесную растительность. При помощи метода пробных площадей был подсчитан видовой состав растительного покрова, определено количество лекарственных видов на каждом объекте. Данный анализ помог рассмотреть экологические последствия деятельности исследуемых горно-обогатительных комбинатов, а также разработать методы снижения риска негативного воздействия.
The article presents the analysis of the environmental effects of the applied mining and processing plant southern Urals on the grassy, tree-shrub and woody vegetation. Using the sample plots were counted species composition of vegetation determine the number of medicinal species at each site. This analysis helped to consider the environmental impact of the activities of the studied mining and processing, and to develop methods to reduce the risk of adverse effects
Epidemiology and impact of colonization by multidrug-resistant Gram-negative bacteria on bloodstream infections in early phase of allogeneic hematopoietic stem cell transplantation
Objective.
To study epidemiology and impact of colonization by multidrug-resistant Gram-negative bacteria (MDRGNB) on bloodstream infections (BSI) during allogeneic hematopoietic stem cell transplantation (allo-HSCT).
Materials and Methods.
The retrospective study included 288 patients received the first allo-HSCT between 2018 and 2019. The median age was 32 (18–66) years, male – 53% (n = 152). The majority of patients had acute leukemia – 62% (n = 178) and received transplant from matched unrelated – 42% (n = 120) or haploidentical donor – 26% (n = 75). Relapse of underlying disease at the moment of all-HSCT was registered in 23% (n = 66) of patients.
Results.
Colonization of non-sterile sites before allo-HSCT by at least one MDRGNB was detected in 28% (n = 64). In most cases resistance is due to extended spectrum beta-lactamases (ESBL) – 86% (n = 55), while carbapenemases in combination with ESBL were detected in 14% (n = 9) of patients. After allo-HSCT the colonization was significantly higher than before transplantation (n = 161, 56%, p = 0.001), mainly due to carbapenemase- and ESBL-producing bacteria – 73% (n = 118) (p = 0.001). BSI in the early period after transplantation developed in 26% (n = 76), and in 56% (n = 43) was caused by MDRGNB. The etiology of BSI included K. pneumoniae – 51% in mostly cases. The etiology of BSI was the same bacteria that colonized non-sterile sites 2 weeks before the detection bacteria in bloodstream in 69% (n = 30) patients. Colonization by MDRGNB was associated with the development of BSI (p < 0.0001). The 100-day overall survival (OS) after all-HSCT was significantly lower in patients with colonization of non-sterile sites by MDRGNB compared with patients without colonization (60.6% vs 88.2%, p = 0.001).
Conclusions.
Colonization of MDRGNB after allo-HSCT reached 56%. K. pneumoniae was predominant etiology in both colonization and bloodstream infections. Colonization by MDRGNB was associated with the development of BSI and decreased OS after allo-HSCT
On the evaluation of a certain class of Feynman diagrams in x-space: Sunrise-type topologies at any loop order
We review recently developed new powerful techniques to compute a class of
Feynman diagrams at any loop order, known as sunrise-type diagrams. These
sunrise-type topologies have many important applications in many different
fields of physics and we believe it to be timely to discuss their evaluation
from a unified point of view. The method is based on the analysis of the
diagrams directly in configuration space which, in the case of the sunrise-type
diagrams and diagrams related to them, leads to enormous simplifications as
compared to the traditional evaluation of loops in momentum space. We present
explicit formulae for their analytical evaluation for arbitrary mass
configurations and arbitrary dimensions at any loop order. We discuss several
limiting cases of their kinematical regimes which are e.g. relevant for
applications in HQET and NRQCD.Comment: 100 pages, 16 eps-figures include
Long-Baseline Neutrino Facility (LBNF) and Deep Underground Neutrino Experiment (DUNE) Conceptual Design Report Volume 2: The Physics Program for DUNE at LBNF
The Physics Program for the Deep Underground Neutrino Experiment (DUNE) at the Fermilab Long-Baseline Neutrino Facility (LBNF) is described
Highly-parallelized simulation of a pixelated LArTPC on a GPU
The rapid development of general-purpose computing on graphics processing units (GPGPU) is allowing the implementation of highly-parallelized Monte Carlo simulation chains for particle physics experiments. This technique is particularly suitable for the simulation of a pixelated charge readout for time projection chambers, given the large number of channels that this technology employs. Here we present the first implementation of a full microphysical simulator of a liquid argon time projection chamber (LArTPC) equipped with light readout and pixelated charge readout, developed for the DUNE Near Detector. The software is implemented with an end-to-end set of GPU-optimized algorithms. The algorithms have been written in Python and translated into CUDA kernels using Numba, a just-in-time compiler for a subset of Python and NumPy instructions. The GPU implementation achieves a speed up of four orders of magnitude compared with the equivalent CPU version. The simulation of the current induced on 10^3 pixels takes around 1 ms on the GPU, compared with approximately 10 s on the CPU. The results of the simulation are compared against data from a pixel-readout LArTPC prototype
Theory of nonstationary homogeneous nucleation Part 2
12.00; Translated from Russian (Fiz. Khim. Obrab. Mater. 1985 v. 19(6) p. 61-65)Available from British Library Document Supply Centre- DSC:9023.19(VR--3410)T / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo
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