bluuebunny/crossref_metadata_2025 huggingface dataset:
Unobtrusive Non-Contact Detection of Arrhythmias using a “Smart” Bed
Authors: Brueser Ch.
Published: March 2021

We present an instrumented bed for unobtrusive, non-contact monitoring of cardiac and respiratory activity. The system presented here is based on the principle of ballistocardiography (BCG), and measures cardiopulmonary vibrations of the body by means of an electromechanical foil (EMFi) attached to the mattress. Using our system, a clinical study with 13 participants was conducted to assess the BCG’s ability to distinguish atrial fibrillations from normal sinus rhythms. By computing a time-frequency representation of the recorded signals based on parametric autoregressive estimators, we can show clear qualitative differences between normal and arrhythmic BCG episodes. The same distinctive features could also be observed when applying our method to a simultaneously recorded reference ECG. Our results suggest that ECG and BCG both contain the same basic information with respect to the presence of atrial fibrillations, and that a bed-mounted BCG sensor can indeed be used to detect atrial fibrillations.
Prague’s Water Supply Station in Podolí — a Solution for the Problems of Clean Water in the 1930s
Authors: Drnek K.
Published: March 2021

In the 1920s Prague was seeking a solution to the problem of supplying its inhabitants with drinkable water. The water plant in Káraný was not able to provide enough water, and the bold plan to bring water from a reservoir and to provide a dual system of potable and non-potable water faced an uncertain future. In order to stave off the crisis and make time to complete its plans, the city council decided to construct a new water supply plant inside the city next to the Vltava river in the city district of Podolí.
Numerically Optimized Uniformly Most Powerful Alphabets for Hierarchical-Decode-and-Forward Two-Way Relaying
Authors: Hekrdla M.
Published: March 2021

We address the issue of the parametric performance of the Hierarchical-Decode-and-Forward (HDF) strategy in a wireless 2-way relay channel. Promising HDF, representing the concept of wireless network coding, performs well with a pre-coding strategy that requires Channel State Information (CSI) on the transceiver side. Assuming a practical case when CSI is available only on the receiver side and the channel conditions do not allow adaptive strategies, the parametrization causes significant HDF performance degradation for some modulation alphabets. Alphabets that are robust to the parametrization (denoted Uniformly Most Powerful (UMP)) have already been proposed restricting on the class of non-linear multi-dimensional frequency modulations. In this work, we focus on the general design of unrestricted UMP alphabets. We formulate an optimization problem which is solved by standard non-linear convex constrained optimization algorithms, particularly by Nelder-Mead global optimization search, which is further refined by the local interior-pointsmethod.
Chaos in GDP
Authors: Kříž R.
Published: March 2021

This paper presents an analysis of GDP and finds chaos in GDP. I tried to find a nonlinear lower-dimensional discrete dynamic macroeconomic model that would characterize GDP. This model is represented by a set of differential equations. I have used the Mathematica and MS Excel programs for the analysis.
Synthesis of Room Impulse Responses for Variable Source Characteristics
Authors: Kunkemoeller M. , Dietrich P. , Pollow M.
Published: March 2021

Every acoustic source, e.g. a speaker, a musical instrument or a loudspeaker, generally has a frequency dependent characteristic radiation pattern, which is preeminent at higher frequencies. Room acoustic measurements nowadays only account for omnidirectional source characteristics. This motivates a measurement method that is capable of obtaining room impulse responses for these specific radiation patterns by using a superposition approach of several measurements with technically well-defined sound sources. We propose a method based on measurements with a 12-channel independentlydriven dodecahedron loudspeaker array rotated by an automatically controlled turntable.Radiation patterns can be efficiently described with the use of spherical harmonics representation. We propose a method that uses this representation for the spherical loudspeaker array used for the measurements and the target radiation pattern to be used for the synthesis.We show validating results for a deterministic test sound source inside in a small lecture hall.
Limited Angle Torque Motors Having High Torque Density, Used in Accurate Drive Systems
Authors: Obreja R. , Edu I. R.
Published: March 2021

A torque motor is a special electric motor that is able to develop the highest possible torque in a certain volume. A torque motor usually has a pancake configuration, and is directly jointed to a drive system (without a gear box). A limited angle torque motor is a torque motor that has no rotary electromagnetic field — in certain papers it is referred to as a linear electromagnet. The main intention of the authors for this paper is to present a means for analyzing and designing a limited angle torque motor only through the finite element method. Users nowadays require very high-performance limited angle torque motors with high density torque. It is therefore necessary to develop the highest possible torque in a relatively small volume. A way to design such motors is by using numerical methods based on the finite element method.
Cataclysmic Variables — X-rays and Optical Activity in V1223 Sgr and V709 Cas
Authors: Gális R. , Hric L. , Kundra E. , Münz F.
Published: March 2021

Intermediate polars are a major fraction of all cataclysmic variables detected by INTEGRAL in hard X-ray. These objects have recently been proposed to be the dominant X-ray source population detected near the Galactic centre, and they also contribute significantly to X-ray diffuse Galactic ridge emission. Nevertheless, only 25% of all known intermediate polars have been detected in hard X-ray. This fact can be related to the activity state of these close interacting binaries.A multi-frequency (from optical to X-ray) investigation of intermediate polars is essential for understanding the physical mechanisms responsible for the observed activity of these objects.
Observing Galaxy Clusters with eROSITA: Simulations
Authors: Hölzl J. , Wilms J. , Kreykenbohm I. , Schmid Ch. , Grossberger Ch. , Wille M. , Eikmann W. , Brand T.
Published: March 2021

The eROSITA instrument on board the Russian Spectrum Roentgen Gamma spacecraft, which will be launched in 2013,will conduct an all sky survey in X-rays. A main objective of the survey is to observe galaxy clusters in order to constrain cosmological parameters and to obtain further knowledge about dark matter and dark energy. For the simulation of the eROSITA survey we present a Monte-Carlo code generating a mock catalogue of galaxy clusters distributed accordingto the mass function of [1]. The simulation generates the celestial coordinates as well as the cluster mass and redshift. From these parameters, the observed intensity and angular diameter are derived. These are used to scale Chandra cluster images as input for the survey-simulation.
A Crazy Question: Can Apparently Brighter Gamma-ray Bursts Be Farther Away?
Authors: Mészáros A. , Řípa J. , Ryde F.
Published: March 2021

The cosmological relationships between observed and emitted quantities are determined for gamma-ray bursts (GRBs). The relationship shows that apparently fainter bursts need not, in general, lie at larger redshifts.This is possible when the luminosities (or emitted energies) in a sample of bursts increase faster than the dimming of the observed values with redshift. Four different samples of long bursts suggest that this is what really happens.
Thermal Forming of Glass — Experiment vs. Simulation
Authors: Švéda L. , Landováa M. , Míka M. , Pína L. , Havlíková R. , Maršíková V.
Published: March 2021

Thermal forming is a technique for forming glass foils precisely into a desired shape. It is widely used in the automotive industry. It can also be used for shaping X-ray mirror substrates for space missions, as in our case. This paper presents the initial results of methods used for automatic data processing of in-situ measurements of the thermal shaping process and a comparison of measured and simulatated values. It also briefly describes improvements of the overall experimental setup currently being made in order to obtain better and more precise results.
Ultra Low Dispersion Spectroscopy with Gaia and Astronomical Slitless Surveys
Authors: Hudec R. , Hudec L. , Klíma M.
Published: March 2021

The ultra-low dispersion spectroscopy to be applied in the ESA Gaia space observatory and the ground-based objective-prism plate surveys represent a similar type of astrophysical data. Although the dispersion in plate surveys is usually larger than in the Gaia blue and red photometers (BP/RP), the spectral resolutions differ by a factor of 2–3 only, since the resolution in ground-based spectra is seeing-limited. We argue that some of the algorithms developed for digitized objective-prism plates can also be applied for the Gaia spectra. At the same time, the plate results confirm the feasibility of observing strong emission lines with Gaia RP/BP.
S5 1803+78 Revisited
Authors: Nesci R. , Maselli A. , Montagni F. , Sclavi S.
Published: March 2021

We report on our optical monitoring of the BL Lac object S5 1803+78 from 1996 to 2011. The source showed no clear periodicity, but a time scale of about 1 300 days between major flares is possibly present. No systematic trend of the color index with flux variations is evident, at variance with other BL Lacs. In one flare, however, the source was bluer in the rising phase and redder in the falling one. Two ?-ray flares were detected by Fermi-GST during our monitoring: on the occasion of only one of them we found simultaneous optical brightening. A one-zone Synchrotron Self Compton (SSC) model appears too simple to explain the source behavior.
Utilization of Image Intensifiers in Astronomy
Authors: Vítek S. , Fliegel K. , Páta P. , Koten P.
Published: March 2021

In this paper we present the properties of image intensifiers, used together with fast TV cameras for astronomical purposes within the MAIA project(Meteor Automatic Imager and Analyser, primarily focused on observing meteoric events with high time resolution). The main objective of our paper is to evaluate the suitability of these devices for astronomical purposes in terms of noise, temporal and spectral analysis.
A Thermogravimetric Study of the Behaviour of Biomass Blends During Combustion
Authors: Jiříček Ivo , Rudasová Pavla , Žemlová Tereza
Published: March 2021

The ignition and combustion behavior of biomass and biomass blends under typical heating conditions were investigated. Thermogravimetric analyses were performed on stalk and woody biomass, alone and blended with various additive weight ratios. The combustion process was enhanced by adding oxygen to the primary air. This led to shorter devolatilization/pyrolysis and char burnout stages, which both took place at lower temperatures than in air alone. The results of the ignition study of stalk biomass show a decrease in ignition temperature as the particle size decreases. This indicates homogeneous ignition, where the volatiles burn in the gas phase, preventing oxygen from reaching the particle surface.The behavior of biomass fuels in the burning process was analyzed, and the effects of heat production and additive type were investigated. Mixing with additives is a method for modifying biofuel and obtaining a more continuous heat release process. Differential scanning calorimetric-thermogravimetric (DSC-TGA) analysis revealed that when the additive is added to biomass, the volatilization rate is modified, the heat release is affected, and the combustion residue is reduced at the same final combustion temperature.
Energy Recovery from Contaminated Biomass
Authors: Moskalík Jiří , Škvařil Jan , Štelcl Otakar , Baláš Marek , Lisý Martin
Published: March 2021

This study focuses on thermal gasification methods of contaminated biomass in an atmospheric fluidized bed, especially biomass contaminated by undesirable substances in its primary use. For the experiments, chipboard waste was chosen as a representative sample of contaminated biomass. In the experiments, samples of gas and tar were taken for a better description of the process of gasifying chipboard waste. Gas and tar samples also provide information about the properties of the gas that is produced.
Energy Accumulation by Hydrogen Technologies
Authors: Čermáková Jiřina , Doucek Aleš , Polák Lukáš
Published: March 2021

Photovoltaic power plants as a renewable energy source have been receiving rapidly growing attention in the Czech Republic and in the other EU countries. This rapid development of photovoltaic sources is having a negative effect on the electricity power system control, because they depend on the weather conditions and provide a variable and unreliable supply of electric power. One way to reduce this effect is by accumulating electricity in hydrogen. The aim of this paper is to introduce hydrogen as a tool for regulating photovoltaic energy in island mode. A configuration has been designed for connecting households with the photovoltaic hybrid system, and a simulation model has been made in order to check the validity of this system. The simulation results provide energy flows and have been used for optimal sizing of real devices. An appropriate system can deliver energy in a stand-alone installation.
New Abrasive Materials and Their Influence on the Surface Quality of Bearing Steel After Grinding
Authors: Jusko Ondrej
Published: March 2021

This paper focuses on the influence of various types of abrasive grains on cutting properties during the grinding process for bearing steel. In this experiment, not only conventional super-hard abrasive materials but also a new type of abrasive material were employed in grinding wheels. The measurement results were compared, and an evaluation was made of the cutting properties of the new abrasive material. The options were then evaluated for their practical applicability. The measurement results indicated that a grinding wheel with Abral and SG grains is the most suitable for grinding hardened bearing steel in order to achieve the best roughness and geometrical accuracy.
Metallurgical Joining of Magnesium Alloys by the FSW Process
Authors: Kupec Tomáš , Hlavačová Ivana , Turňa Milan
Published: March 2021

This paper deals with welding AZ 31Mg alloy by FSW (Friction Stir Welding) technology. Welds were fabricated with new equipment supplied from China for VUZ-PI Bratislava (Welding Research Institute — Industrial Institute). Welding parameters and conditions were proposed and tested. Joint quality was assessed by optical microscopy and microhardness measurements. The fabricated joints were sound, apart from minor inhomogeneities (cracks). It is considered that after certain adaptations of the welding parameters, and perhaps also of the welding tool, that this equipment will be capable of producing welded joints of excellent quality that can compete with any fusion welding technologies, including concentrated power sources.
Simulation of a Matrix Converter Fed Drive With Sliding Mode Control
Authors: Bauer Jan
Published: March 2021

Induction machines are among the most widely used electrical-to-mechanical converters in electric drives. Their advantageous robustness and simplicity goes hand-in-hand with complicated control. A converter with a suitable control algorithm is needed in order to withdraw maximum power and dynamics from the drive. In recent times, control methods such as those based on DTC and sliding mode methods have come to the forefront, due to their robustness and relative simplicity.In the field of power converters, new converter topologies are emerging with improved efficiency that pushes the operation limits of the drive. This paper focuses on the development of a control of this kind of strategy for an induction machine fed from a matrix converter.
Development of an Ultralight with a Ducted Fan
Authors: Brabec Jiří , Helmich Martin
Published: March 2021

This paper introduces the UL-39 project, an ultralight aircraft with a ducted fan, and some of the problems that have arisen in the course of its development. Several problems with the design of a non-traditional aircraft of this kind are mentioned, e.g. the design of the airframe, and the design of the propulsion unit. The paper describes the specific procedure for determining the basic thrust characteristics of this unusual aircraft concept, and also the experimental determination of these characteristics. Further options for applying the experience gained during the work, and the futurefocus of work on these issues, are outlined at the end of the paper.
Diamond Films for Implantable Electrodes
Authors: Henychová Petra , Hiřmanová Klára , Vraný Martin
Published: March 2021

Diamond is a promising material for implantable electrodes due to its unique properties. The aim of this work is to investigate the growth of boron-doped nanocrystalline diamond (B-NCD) films by plasma-enhanced microwave chemical vapor deposition at various temperatures, and to propose optimal diamond growth conditions for implantable electrodes. We have investigated the temperature dependence (450 °C–820 °C) of boron incorporation, surface morphology and growth rate on a polished quartz plate. Surface morphology and thickness were examined by atomic force microscopy (AFM).The quality of the films in terms of diamond and non-diamond phase of carbon was investigated by Raman spectroscopy. AFM imaging showed that the size of the grains was determined mainly by the thickness of the films, and varied from an average size of 40 nm in the lowest temperature sample to an average size of 150 nm in the sample prepared at the highest temperature. The surface roughness of the measured samples varied between 10 (495 °C) and 25 nm (800 °C). The growth rate of the sample increased with temperature. We found that the level of boron doping was strongly dependent on temperature during deposition. An optimal B-NCD sample was prepared at 595 °C.
ESSO — Electrification of the Central Labe Districts between 1916 and 1950
Authors: Holovský Jan
Published: March 2021

Elektrárenský svaz stredolabských okresu, LLC (in English “The Power Plant Union of the Central Labe (Elbe)” districts, which will be referred to here as “ESSO”), came into existence in 1916 in response to growing interest in electrification of the surroundings of Kolín. The Union was an extension of Križík’s earlier activities. Most of the power was produced by Križík’s power plant, which was extensively refurbished between 1919 and 1923. In 1919, the hydroelectric power plant in Podebrady was connected to the mains. Between 1924 and 1935, the Union gradually took over the hydroelectric power stations in Nymburk (1924), Kolín (1931), and Prelouc (1935). The Union´s most extensive project for a new steam power plant located in Kolín was initiated in 1929. The first stage of construction of the power plant was completed in 1932. It should be noted that the structure was designed by the well-known architect Jaroslav Fragner. The Union significantly influenced the electrification process for the central Labe district and its surroundings. The Union also successfully extended the number of electricity users. In addition, its activities raised the standard of living of the local citizens. The Union, which had already been nationalized, ceased to exist in 1950.
Accelerometer-assisted PPG Measurement During Physical Exercise Using the LAVIMO Sensor System
Authors: Santos Susana Aguiar , Venema Boudewijn , Leonhardt Steffen
Published: March 2021

A method is presented for long-term monitoring of vital signs tested during physical exercise. The system is based on reflective photoplethysmography (PPG), whose main component is a micro-optoelectronic sensor. The sensor is sealed within a biocompatible otoplastic housing so that it can be placed in the external auditory canal. The electronic device has a Bluetooth connection which enables to record/visualize the PPG signal on a personal computer or SmartPhone. This technology was tested indoors with a subject running on a treadmill at different speeds. The PPG signal was recorded together with an ECG used as a reference, and with an accelerometer to monitor and record motor activity. Theaccelerometer data were later used to reduce motion artifacts in the PPG signal. The results show that the system has potential to monitor cardiac activity at moderate speed (up to 4 km/h), but with increasing speed (i.e. running) the motion artifacts dominate the PPG. Therefore, additional studies on signal processing are needed to actively reduce motion artifacts, including the accelerometer data.
Control Algorithms for Large-scale Single-axis Photovoltaic Trackers
Authors: Schneider Dorian
Published: March 2021

The electrical yield of large-scale photovoltaic power plants can be greatly improved by employing solar trackers. While fixed-tilt superstructures are stationary and immobile, trackers move the PV-module plane in order to optimize its alignment to the sun. This paper introduces control algorithms for single-axis trackers (SAT), including a discussion for optimal alignment and backtracking. The results are used to simulate and compare the electrical yield of fixed-tilt and SAT systems. The proposed algorithms have been field tested, and are in operation in solar parks worldwide.
Physical and Chemical Aspects of the Nucleation of Cement-Based Materials
Authors: Demo Pavel , Sveshnikov Alexey , Hošková Šárka , Ladman David , Tichá Petra
Published: March 2021

A theoretical model of the nucleation of portlandite is proposed, and the critical size of a portlandite cluster and the energy barrier of nucleation are determined. The steady state nucleation rate and the time lag of the nucleation of portlandite are estimated for a pure solution of Ca(OH)2 in water. Possible connections with the corresponding properties for cement paste are discussed. A new method is developed for experimentally determining the concentration of Ca2+ ions during the initial stage of hydration of a cement paste. The time dependence of Ca2+ ions is measured for various water-to-cement ratio values. The results are discussed from the point of view of existing models of the induction period.
Hierarchical Modeling of Mastic Asphalt in Layered Road Structures Based on the Mori-Tanaka Method
Authors: Valenta Richard , Šejnoha Michal
Published: March 2021

We present an application of the Mori-Tanaka micromechanical model for a description of the highly nonlinear behavior of asphalt mixtures. This method is expected to replace an expensive finite element-based fully-coupled multi-scale analysis while still providing useful information about local fields on the meso-scale that are not predictable by strictly macroscopic simulations. Drawing on our recent results from extensive experimental and also numerical investigations this paper concentrates on principal limitations of the Mori-Tanaka method, typical of all two-point averaging schemes, when appliedto material systems prone to evolving highly localized deformation patterns such as a network of shear bands. The inability of the Mori-Tanaka method to properly capture the correct stress transfer between phases with increasing compliance of the matrix phase is remedied here by introducing a damage like parameter into the local constitutive equation of reinforcements (stones) to control an amount of stress taken by this phase. A deficiency of the Mori-Tanaka method in the prediction of creep response is also mentioned particularly in the light of large scale simulations. A comparison with the application of macroscopic homogenized constitutive model for an asphalt mixture is also presented.
Global Optima for Size Optimization Benchmarks by Branch and Bound Principles
Authors: Pospíšilová Adéla , Lepš Matej
Published: March 2021

This paper searches for global optima for size optimization benchmarks utilizing a method based on branch and bound principles. The goal is to demonstrate the process for finding these global optima on the basis of two examples. A suitable parallelization strategy is used in order to minimize the computational demands. Optima found in the literature are compared with the optima used in this work.
The Asymptotic Properties of Turbulent Solutions to the Navier-Stokes Equations
Authors: Skalák Zdenek
Published: March 2021

In this paper we study the large time behavior of solutions to the Navier-Stokes equations. We present a brief survey of results concerning energy decay, and discuss a related phenomenon of the large time energy concentration in the frequency space occurring in any turbulent solution. This leads us to the study of solutions in the Besov spaces and to proof that if we choose a suitable initial condition then in some Besov spaces the energy of the associated solution does not decrease asymptotically to zero.
Transonic Flow of Wet Steam — Numerical Simulation
Authors: Halama Jan
Published: March 2021

The paper presents a numerical simulation of the transonic flow of steam with a non-equilibrium phase change. The flow of steam is approximated by a mixture model complemented by transport equations for moments. Proper formulation of the problem consists of domain definition, a complete set of equations, and appropriate choice of initial and boundary conditions. This problem is then solved numerically by a numerical code, that has been developed in-house. The code is based on a fractional step method and a finite volume formulation. Important issues related to numerical solution are discussed. Results for flow in a turbine are presented.
Not that simple goiter
Authors: Gerasimov Gregory A.
Published: March 2021

The year 2020 marks the centenary of the publication of a classic study by American physicians D. Marine and O. Kimball on the effectiveness of endemic goiter prevention in children in Akron, Ohio. Although goiter has been known from immemorial times, there is still a problem with determining the normal size of the thyroid gland, without which the diagnosis of goiter remains extremely subjective. For example, in Sweden over the past 20 years, not a single case of endemic goiter has been registered, which is not surprising: the country eliminated this pathology decades ago, and the median urinary iodine concentration indicates the optimal iodine intake. Cases of sporadic goiter in children in Sweden are also rare — no more than 6–8 per year. But in Belarus, with the same population (about 10 million), about 2900 cases of goiter in children, both endemic and sporadic, are recorded annually despite the fact that, due to the extensive use of iodized salt since the beginning of the 2000s, there is no iodine deficiency. The incidence of goiter in children, however, having decreased many times over the past 20 years, remains 3 times higher than in Russia, where iodine prophylaxis, if carried out on a limited scale. From the experience of Belarus, Sweden and Russia, we see that the main thing when assessing data on the incidence of goiter and other thyroid diseases associated with iodine deficiency should be not absolute numbers, but the trend of these indicators over the past years. This information should be more actively used by endocrinologists in Russia to assess the effectiveness of preventive measures both at the regional and federal levels.
Endogenous and exogenous interferences in thyroid function immunoassays
Authors: Kim Ekaterina I. , Dimitrova Diana А. , Dimitrova Diana A. , Katamadze Nino N. , Dzantieva Tamara S.
Published: March 2021

Laboratory diagnosis of endocrine diseases has undergone many important changes over the past decades, despite the progress of thyroid function immunoassays technologies interferences cannot be completely excluded. These interferences can affect measurement of analyte which leads to misinterpretation and subsequent wrong clinical decisions, the probability of which is about 1%. However, the scale of the problem may be greater due to the lack of awareness to the problem among doctors and the lack of laboratory screening for interfering factors. These factors can be both endogenous and exogenous, bind both to antibodies to the analyte and to the reagent in the test system. The specificity of the immunoassay depends not only on the binding properties of antibodies, the activity of reagent, but also on the composition of the test system and the format of the methodology (non-competitive two-site or “sandwich” and competitive assays).

This review provides a description of the main interferences that can affect the measurement of thyroid hormones, in particular thyroid stimulating hormone, free thyroxine and triiodothyronine, calcitonin, and demonstrates clinical cases reported in the literature over the past few years.
POLA ASUH ANAK DI TENGAH PANDEMI COVID-19: Pendekatan Humanistik dalam mendukung Tumbuh Kembang Anak
Authors: Effendi Yusuf
Published: March 2021

The COVID-19 pandemi has made all children's activities ranging from teaching and learning activities to self-development to be carried out at home. Parents are required to be able to guide and facilitate all their children's needs to ensure that children can learn and develop well. For that we need a good parenting style and support the child's self development. The purpose of this study is to find a complete integration of parenting patterns based on Abraham Maslow's humanistic concept to ensure the fulfillment of children's needs amid the COVID-19 pandemi while ensuring that children develop well. This study uses a qualitative research method with a literature approach to collect, study and analyze a complete concept of parenting in the midst of a pandemic. This research found that the integration of humanistic concepts in parenting in the midst of the COVID-19 pandemi resulted in a holistic parenting concept by paying attention to several aspects such as the fulfillment of physiological needs, security, love and affection, self-esteem and culminating in self-actualization where children are capable. understand and develop self potential well. Keyword : COVID-19, Pandemi, Parenting, Humanistic Psychology
Effect of adding rare-earth cerium on the microstructure and acid rain corrosion resistance of the ADC12 alloy
Authors: Zhang LiJie , Yan Hong , Zou YongCheng , Yu BaoBiao , Hu Zhi
Published: March 2021

The effect of adding cerium on the microstructure and acid rain corrosion resistance of the AlSi11Cu3 alloy was investigated by means of optical microscopy, scanning electron microscopy, and energy dispersive spectroscopy. The AlSi11Cu3 alloy was doped with varying stoichiometries of cerium to generate AlSi11Cu3-xCe, where x = 0, 0.5, 1.0, and 1.5 wt.%. The results show that the α-Al, eutectic Si, and β-Al5FeSi phases in the AlSi11Cu3-1.0Ce alloy are significantly refined. Electrochemical tests demonstrated an increase in the self-corrosion potential value of the AlSi11Cu3-1.0Ce alloy from –670 mV to –628 mV relative to the untreated alloy. In addition, the AlSi11Cu3-1.0Ce alloy has the lowest corrosion current density (8.4 μA × cm–2). Immersion corrosion testing on the AlSi11Cu3-1.0Ce alloy revealed a corrosion rate of 0.71 mg × cm–2 × d–1, constituting a 72% reduction in the corrosion rate compared to the untreated alloy. These results indicate that the AlSi11Cu3-1.0Ce alloy has a high resistance to acid rain corrosion, which is the result of a refinement of the cathode phases.
Effect of TiO2 crystal form on the denitration performance of Ce–W–Ti catalyst
Authors: Bian Xue , Yu Yuntao , Hao Nana , Wu Wenyuan
Published: March 2021

Titanium dioxide supports, which were prepared by roasting metatitanic acid under different conditions, were used to prepare a series of Ce–W–Ti catalysts. The structure and denitration properties of the catalyst were studied. The results showed that TiO2 had different crystal types (mixed crystal phases with different proportions of anatase and rutile) under different roasting conditions, and the denitration efficiency of mixed crystal was better than that of pure phase TiO2. Ce–W/200 °C-1 hTiO2 catalyst exhibited a prominent NO conversion rate, and it can reach higher than 90% at a temperature range from 250 to 500°C. The large specific surface area, low content of rutile TiO2 in the support, high content of chemical adsorbed oxygen and high surface acidity were favorable to denitration performance of Ce–W–Ti catalyst.
Comparison of simulation observer tools on engagement and maximising learning: a pilot study
Authors: Johnston Sandra , Tutticci Naomi , Theobald Karen , Ramsbotham Joanne
Published: March 2021

Objectives

This pilot study examined if the Clinical Reasoning Observer Worksheet (CROW) compared to a standard observer worksheet used during simulation, would enhance nursing students active learning behaviours and perceptions of clinical reasoning ability.

Methods

This pilot study was undertaken to test the design and processes for a future larger study and reports on preliminary evidence of efficacy of recruitment procedures and instrumentation in addition to student’s learning outcomes.

Results

There was little overall difference in outcomes between groups who used either simulation observer worksheet. Overall, participants who used either worksheet perceived their ability to apply clinical reasoning to an episode of patient care increased.

Conclusions

Modifications were identified as necessary for a larger study including changes to instrumentation, method of survey delivery and training of simulation facilitators. A more definitive evaluation will be achievable with a larger group of students in a main study with the suggested modifications.
OverCOVID: an integrative web portal for SARS-CoV-2 bioinformatics resources
Authors: Ahsan Md. Asif , Liu Yongjing , Feng Cong , Hofestädt Ralf , Chen Ming
Published: March 2021

Outbreaks of COVID-19 caused by the novel coronavirus SARS-CoV-2 is still a threat to global human health. In order to understand the biology of SARS-CoV-2 and developing drug against COVID-19, a vast amount of genomic, proteomic, interatomic, and clinical data is being generated, and the bioinformatics researchers produced databases, webservers and tools to gather those publicly available data and provide an opportunity of analyzing such data. However, these bioinformatics resources are scattered and researchers need to find them from different resources discretely. To facilitate researchers in finding the resources in one frame, we have developed an integrated web portal called OverCOVID (http://bis.zju.edu.cn/overcovid/). The publicly available webservers, databases and tools associated with SARS-CoV-2 have been incorporated in the resource page. In addition, a network view of the resources is provided to display the scope of the research. Other information like SARS-CoV-2 strains is visualized and various layers of interaction resources is listed in distinct pages of the web portal. As an integrative web portal, the OverCOVID will help the scientist to search the resources and accelerate the clinical research of SARS-CoV-2.
How words make the world: language materialities and the circulation of the Sakha algys
Authors: Ferguson Jenanne
Published: March 2021

This article investigates contemporary uses of the Sakha language algys (blessing poems) and reveals the “old” and “new” types of language materiality present in this genre of ritual poetry. Focusing primarily on one example of algys shared online in 2018, I discuss how performing algys has always involved close interconnection between language and the material world and present the changing contexts and forms of algys transmission that highlight both fixity and fluidity in the way speakers conceive of language and materiality. Despite the new mobilities and technologies that build upon the previously established written textual forms of this poetry—and contribute to its continued circulation and transmission—certain elements of traditional algys remains salient for speakers, reinforced by ideologies or ontologies of language that foreground the power of the (spoken) word. This is connected to the production of qualia and the invocation of chronotopes. Thus, while textual forms further enable processes of citationality as they are circulated online; the written words alone do not constitute an algys. Rather, here the importance of embodied, spoken language materiality is at the fore.
The crystal structure of 2-amino-5-nitroanilinium iodide monohydrate, C6H8IN3O2
Authors: Du Chao-Jun , Niu De-Long , Zheng Shi-Li , Zeng Yan
Published: March 2021

C6H8IN3O2, monoclinic, P21/n (no. 14), a = 7.0704(3) Å, b = 15.7781(6) Å, c = 9.1495(4) Å, β = 112.114(1)°, V = 945.61(7) Å3, Z = 4, R

gt
(F) = 0.0187, wR

ref
(F
2) = 0.0522, T = 150(2) K.
Perceived Neighborhood Walkability is Associated with Recent Falls in Urban Dwelling Older Adults
Authors: Blackwood Jennifer , Suzuki Rie , Karczewski Hannah
Published: March 2021

Background and Purpose:

In rural communities, perceptions of neighborhood walkability, the rating of how easy it is to walk in an area, influence engagement in physical activity outside the home. This has not been studied in older adults residing in urban settings. Additionally, it is not known how perceived walkability is associated with falls. Therefore, the purpose of this study was to first describe the perceptions of neighborhood walkability in urban-dwelling older adults based on recent fall history and then examine associations between recent falls and neighborhood walkability constructs after controlling for fall risk factors.

Methods:

Urban-dwelling older adults (N = 132) 65 years and older without cognitive dysfunction or uncontrolled comorbidity completed a survey assessing health status, physical activity, and walkability using the Neighborhood Environment Walkability Scale-Abbreviated. Group assignment was based on recent fall history. Between-group comparisons of demographic and walkability constructs were completed using analysis of variance. Logistic regression was used to examine associations between walkability constructs and recent falls after controlling for covariates.

Results and Discussion:

Poorer perception of land use was significantly associated with recent falls. Questions assessing the ease of walking to a store or transit stop may be valuable in understanding fall risk in older adults living in urban settings.

Conclusions:

Perceptions of neighborhood walkability are lower in urban-dwelling older adults with a history of falling.
Review of the Mechanical Properties of High-Strength Alloys at Cryogenic Temperatures
Authors: Umezawa Osamu
Published: March 2021

To advance the understanding of metallic materials for structural components at cryogenic temperatures, a review of previous studies on the mechanical properties of austenitic stainless steels, titanium alloys, aluminum alloys, and copper alloys is presented herein. In particular, the evaluation of strength and toughness balance intends to clarify key differences between these alloys to facilitate better alloy design and potentially bolster further alloy development. Several key points on cryogenic mechanical tests are also introduced. Temperature control, testing tools, and test conditions should be properly calibrated to avoid experimental errors. Furthermore, substantial progress for subsurface crack initiation in high-cycle fatigue at cryogenic temperatures is presented, in which the mechanism of subsurface crack generation is highlighted as a key design consideration in microstructure of high-strength alloys.
Confirming the Brain Death and the Nurse’s Tasks in the Care of Potential Organ Donors and Their Families
Authors: Haor Beata , Wróblewska Sylwia , Daszuta Klaudia , Daszuta Dominik
Published: March 2021

Introduction. Transplantology is the youngest area of medicine dealing with organ transplantation that is considered to be the most difficult.Aim. The aim of the work is to analyse the nurse’s tasks in the care of the organ donor after confirming brain death and propagate the idea of transplantology.Case Report. A 52-year-old patient admitted to the hospital at the neurological department after a craniocerebral trauma. Computed tomography of the head showed brain contusion, fractures of the bones of the skull cover, the presence of a small amount of air in the cranial cavity. Immediately after admission, the patient was tangled, conscious, reluctant to answer questions, without paresis and a short-term seizure. Anti-oedema and anti-epileptic treatment was implemented in the neurosurgery department. After starting treatment, there was a temporary improvement, followed by a secondary worsening of brain and brain stem failure with deep cerebral coma. The patient was referred for further treatment in the Intensive Care Unit.Discussion. Organ transplantation involves collecting them from the donor and implanting them into the recipient. The donor can be either a living person (when it comes to paired organs or fragment of the liver as well as the tissues and cells) or the deceased person, who during their life did not express objection to organ donation after their death. The major principle in this case is the pronouncement of brain death, i.e. confirmation of patient’s death resulting in changing the therapeutic goals.Conclusions. Transplantology is an interdisciplinary field of medicine, the success of which relies on the cooperation of many professionals. The nurse takes an active part in the team’s work starting from the donor’s organs eligibility, through transplantation, to the care of the patient after the transplantation. The nurse also participates in building up an atmosphere favourable for good relations with the potential donor’s family. (JNNN 2019;8(3):124–132)
Clinical and Sociodemographic Variables and the Level of Social Support in People with Multiple Sclerosis
Authors: Dymecka Joanna
Published: March 2021

Introduction. Multiple sclerosis (MS) is a chronic progressive demyelinating disease of the central nervous system which leads to permanent disability. Social support is a resource that is particularly important in the situation of chronic illness.Aim. The aim of the study was to determine the relationship between clinical and sociodemographic variables and the level of social support in people with multiple sclerosis.Material and Methods. 137 people diagnosed with MS participated in the study. Extended Disability Status Scale (EDSS), Guy’s Neurological Disability Scale (GNDS) and Berlin Social Support Scales were used in the study.Results. Perceived social support is not related to clinical variables such as disability or disease symptoms. However, the relationship between the need for support and disability and some symptoms (i.a. cognitive impairment, mood disorders and intestinal problems) was demonstrated. Women, people married, having children and in better financial condition felt greater social support. Women also need more support and more often seek it.Conclusions. Perceived social support in people with multiple sclerosis is less associated with clinical variables, but more to variables such as gender, marital status or having children. Of the studied types of support, the need for support was most related to the features of the disease. People living with a disability or more severe symptoms need help in daily functioning as well as emotional support. This is also associated with the need for professional support from doctors, psychologists and nurses. (JNNN 2019;8(4):148–156)
Nursing Care of Patient with Acromegaly Disease — Case Report
Authors: Melikoğlu Seçil Erden , Çulha Yeliz , Kaya Hatice , Tanrıöver Necmettin
Published: March 2021

Pituitary tumors are the most common tumors of benign brain tumors, accounting for about one-fifth of all intra cranial tumors. Pituitary tumors include; nonfunctional adenomas and prolactinomas are followed by tumors that secrete growth hormone or acromegaly. Physical changes and systemic complications caused by acromegaly have negative effects on the bio-physiological, psychological and social dimensions of individuals. Diagnosis, treatment, care and follow-up of the disease; It requires a approach to multidisciplinary from endocrine to neurosurgery. The nurse should know the signs and symptoms of the disease, treatment, side effects that may be caused by the treatment, complications and the care interventions to solve the problems that arise and should plan the individualized care to improve the psychological health and quality of life by increasing the individual’s biophysiological functions. The use of the nursing process for the scientific and systematic realization of the care, as well as the use of the nursing process to get her with a model/theory, guide the nurse in the provision of individualized care. In this context, individualized care of the patient who is planned to be operated due to acromegaly, a rare disease, is discussed by integrating with the Model of Nursing. (JNNN 2019;8(4):162–169)
Thrombolysis and Mechanical Thrombectomy as Leading Treatments for Acute Ischemic Stroke
Authors: Filipska Karolina , Wiśniewski Adam , Ślusarz Robert
Published: March 2021

Brain vascular diseases, especially strokes, are still a very serious public health and medicine problem. The world is still facing an epidemic of stroke. With the impact load increasing all over the world, there is a continuing need to understand the characteristics of this disease and its impact in different countries. Despite significant improvements in primary prevention and treatment efficacy over the past decades, stroke is still a debilitating disease. Early treatment is the key to successful recovery of patients with ischemic stroke.The aim of the study is to show the most effective methods of treating patients in the acute phase of ischemic stroke. (JNNN 2019;8(4):177–181)
Health Problems of 80 Plus Patients Reporting to the Hospital Emergency Department, Including Neurological Problems
Authors: Głowacka Mariola , Pietrzak Karolina
Published: March 2021

Introduction. The subject of this wok includes health problems occurring in patients over 80 years of age reporting to the hospital emergency department with an indication of neurological problems.Aim. The aim of this study is to present health problems, including neurological problems, with which patients over 80 years of age report to the hospital emergency department (ER), the most common reasons for hospitalization and how to get to ER.Material and Methods. An analysis of the health situation of patients over 80 years of age was performed who reported to the Hospital Emergency Department of the 10th Military Clinical Hospital with the Polyclinic in Bydgoszcz. The necessary data was obtained by accessing the medical documentation contained in the KS-Medis hospital system. The relationship between the two variables was calculated using Spearman rank correlation coefficient.Results. 80 plus (58%) women most often come to the hospital emergency department because of a fall (11%), brought by a medical emergency system transport (67%). Neurological or co-existing neurological problems (head injuries, strokes or their suspicion) are 6% of the causes of emergency hospitalization.Conclusions. Reasons for seniors over 80 years of age reporting to the hospital emergency department are varied, but falls are dominant. (JNNN 2020;9(1):27–32)