122 research outputs found
Accuracy analysis of reacheble sets computation generalized algebraic approach for linearized discret-time systems
In this paper, problem of reachable set comparison of the nonlinear continuous controlled system and linearized discrete-time system is considered. As the controlled plant we use the model of aircraft in which the motion is described by nonlinear differential equation system. The initial plant model is reduced to linear discrete-time form. The description of generalized recurrent method of the linear system reachable sets computation is provided and the comparative analysis of the received results with an initial reachable set of the nonlinear controlled system is made.Рассматривается задача сравнения областей достижимости непрерывной нелинейной и линеаризованной дискретной управляемых динамических систем. В качестве объекта управления используется модель летательного аппарата, движение которого описывается системой нелинейных динамических уравнений. Производится преобразование исходной модели объекта к дискретному линейному виду. Приводится описание общего алгебраического метода построения области достижимости и производится сравнительный анализ областей достижимости исходной нелинейной непрерывной и линейной дискретной динамических систем
TEnvR: MATLAB-Based Toolbox for Environmental Research
With the advancements in science and technology, datasets become larger and more multivariate, which warrants the need for programming tools for fast data processing and multivariate statistical analysis. Here, the MATLAB-based Toolbox for Environmental Research TEnvR (pronounced ten-ver ) is introduced. This novel toolbox includes 44 open-source codes for automated data analysis from a multitude of techniques, such as ultraviolet-visible, fluorescence, and nuclear magnetic resonance spectroscopies, as well as from ultrahigh resolution mass spectrometry. Provided are codes for processing data (e.g., spectral corrections, formula assignment), visualization of figures, calculation of metrics, multivariate statistics, and automated work-up of large datasets. TEnvR allows for efficient data analysis with minimal by-hand manual work by the user, which allows scientists to do research more efficiently. This manuscript is supplemented with a detailed tutorial, example data, and screenshots, which collectively provide instructions on how to use all codes. TEnvR is novice-friendly and experience in programming with MATLAB is not required. TEnvR fulfills the need for a concise MATLAB-based toolbox for working with environmental data and will be updated annually to keep pace with the latest advances and needs for computational work in the environmental sciences
The Optimal Open-Loop Temonal Control for Spacecraft Rendezvous Problem
The paper proposes a method for solving of optimal terminal open-loop control problem of spacecraft rendez-vous. The initial model is a nonlinear differential equations, which describes the relative motion dynamics in the central gravitational field of the Earth. The original system is replaced by its linear recurrence approximation, and then using the functions of constructing forward and backward reachable sets, the optimal terminal open-loop control problem is solved.В работе предлагается способ решения задачи оптимального программного терминального управления сближением двух космических аппаратов. В качестве исходной модели выбирается нелинейная система дифференциальных уравнений, описывающая динамику относительного движения в центральном поле тяготения Земли. Исходная система заменяется ее линейной рекуррентной аппроксимацией, после чего с использованием аппарата построения прямых и обратных областей достижимости решается задача оптимального программного терминального управления
Biolability of Fresh and Photodegraded Pyrogenic Dissolved Organic Matter From Laboratory-Prepared Chars
Pyrogenic dissolved organic matter (pyDOM) is known to be an important biogeochemical constituent of aquatic ecosystems and the carbon cycle. While recent studies have examined how pyDOM production, composition, and photolability varies with parent pyrogenic solid material type, we lack an understanding of potential microbial mineralization and transformation of pyDOM in the biogeosphere. Thus, leachates of oak, charred at 400 °C and 650 °C, as well as their photodegraded counterparts were incubated with a soil‐extracted microbial consortium over 96 days. During the incubation, significantly more carbon was biomineralized from the lower versus higher temperature char leachate (45% vs. 37% lost, respectively). Further, the photodegraded leachates were biomineralized to significantly greater extents than their fresh non‐photodegraded counterparts. Kinetic modeling identified the mineralizable pyDOC fractions to have half‐lives of 9–13 days. Proton nuclear magnetic resonance spectroscopy indicated that the majority of this loss could be attributed to low molecular weight constituents of pyDOM (i.e., simple alcohols and acids). Further, the quantification of benzenepolycarboxylic acid (BPCA) molecular markers indicated that condensed aromatic compounds in pyDOM were biomineralized to much lesser extents (4.4% and 10.1% decrease in yields of ΣBPCA‐C over 66 days from 400 °C and 650 °C oak pyDOM, respectively), but most of this loss could be attributed to the biomineralization of smaller condensed clusters (four aromatic rings or less). These results highlight the contrasting bioavailability of different portions of pyDOM, and the need to examine both to evaluate its role in soil or aquatic heterotrophy and its environmental fate in the hydrogeosphere
Biolability of Fresh and Photodegraded Pyrogenic Dissolved Organic Matter From Laboratory-Prepared Chars
Pyrogenic dissolved organic matter (pyDOM) is known to be an important biogeochemical constituent of aquatic ecosystems and the carbon cycle. While recent studies have examined how pyDOM production, composition, and photolability varies with parent pyrogenic solid material type, we lack an understanding of potential microbial mineralization and transformation of pyDOM in the biogeosphere. Thus, leachates of oak, charred at 400 °C and 650 °C, as well as their photodegraded counterparts were incubated with a soil‐extracted microbial consortium over 96 days. During the incubation, significantly more carbon was biomineralized from the lower versus higher temperature char leachate (45% vs. 37% lost, respectively). Further, the photodegraded leachates were biomineralized to significantly greater extents than their fresh non‐photodegraded counterparts. Kinetic modeling identified the mineralizable pyDOC fractions to have half‐lives of 9–13 days. Proton nuclear magnetic resonance spectroscopy indicated that the majority of this loss could be attributed to low molecular weight constituents of pyDOM (i.e., simple alcohols and acids). Further, the quantification of benzenepolycarboxylic acid (BPCA) molecular markers indicated that condensed aromatic compounds in pyDOM were biomineralized to much lesser extents (4.4% and 10.1% decrease in yields of ΣBPCA‐C over 66 days from 400 °C and 650 °C oak pyDOM, respectively), but most of this loss could be attributed to the biomineralization of smaller condensed clusters (four aromatic rings or less). These results highlight the contrasting bioavailability of different portions of pyDOM, and the need to examine both to evaluate its role in soil or aquatic heterotrophy and its environmental fate in the hydrogeosphere
Biolability of Fresh and Photodegraded Pyrogenic Dissolved Organic Matter From Laboratory-Prepared Chars
Integrated management of chronic kidney disease: Analysis of an innovative policy in Portugal
The implementation in Portugal of a model for integrated management of disease applied to the end-stage renal disease, from 2008 onwards, has completely restructured the way of providing care, as well as the payment and follow-up of patients under dialysis. This article describes the steps taken by the Ministry of Health, in terms of the planning, implementation and follow-up of the policy, with a particular focus on the importance of involving the various groups of interest, the leadership, as well as the capacity of negotiation and influence of the Government
Continuous and Long-Term Volume Measurements with a Commercial Coulter Counter
We demonstrate a method to enhance the time resolution of a commercial Coulter counter and enable continuous and long-term cell size measurements for growth rate analyses essential to understanding basic cellular processes, such as cell size regulation and cell cycle progression. Our simple modifications to a commercial Coulter counter create controllable cell culture conditions within the sample compartment and combine temperature control with necessary adaptations to achieve measurement stability over several hours. We also wrote custom software, detailed here, to analyze instrument data files collected by either this continuous method or standard, periodic sampling. We use the continuous method to measure the growth rate of yeast in G1 during a prolonged arrest and, in different samples, the dependency of growth rate on cell size and cell cycle position in arrested and proliferating cells. We also quantify with high time resolution the response of mouse lymphoblast cell culture to drug treatment. This method provides a technique for continuous measurement of cell size that is applicable to a large variety of cell types and greatly expands the set of analysis tools available for the Coulter counter.National Institutes of Health (U.S.) (EUREKA Exceptional, Unconventional Research Enabling Knowledge Acceleration (R01GM085457))National Institutes of Health (U.S.) (contract R21CA137695)National Cancer Institute (U.S.). Physical Sciences-Oncology Center (U54CA143874
The need for multidisciplinarity in specialist training to optimize future patient care
Harmonious interactions between radiation, medical, interventional and surgical oncologists, as well as other members of multidisciplinary teams, are essential for the optimization of patient care in oncology. This multidisciplinary approach is particularly important in the current landscape, in which standard-of-care approaches to cancer treatment are evolving towards highly targeted treatments, precise image guidance and personalized cancer therapy. Herein, we highlight the importance of multidisciplinarity and interdisciplinarity at all levels of clinical oncology training. Potential deficits in the current career development pathways and suggested strategies to broaden clinical training and research are presented, with specific emphasis on the merits of trainee involvement in functional multidisciplinary teams. Finally, the importance of training in multidisciplinary research is discussed, with the expectation that this awareness will yield the most fertile ground for future discoveries. Our key message is for cancer professionals to fulfil their duty in ensuring that trainees appreciate the importance of multidisciplinary research and practice
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