bluuebunny/crossref_metadata_2025_split huggingface dataset:
Use of Machine Learning to Identify Clinical Variables in Pregnant and Non-Pregnant Women with SARS-CoV-2 Infection
Authors: Futterman Itamar D. , McLaren Rodney , Friedmann Hila , Musleh Nael , Haberman Shoshana 
Published: September 2022

Abstract
Objective The aim of the study is to identify the important clinical variables found in both pregnant and non-pregnant women who tested positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, using an artificial intelligence (AI) platform.
Methods This was a retrospective cohort study of all women between the ages of 18 to 45, who were admitted to Maimonides Medical Center between March 10, 2020 and December 20, 2021. Patients were included if they had nasopharyngeal PCR swab positive for SARS-CoV-2. Safe People Artificial Intelligence (SPAI) platform, developed by Gynisus, Inc., was used to identify key clinical variables predicting a positive test in pregnant and non-pregnant women. A list of mathematically important clinical variables was generated for both non-pregnant and pregnant women.
Results Positive results were obtained in 1,935 non-pregnant women and 1,909 non-pregnant women tested negative for SARS-CoV-2 infection. Among pregnant women, 280 tested positive, and 1,000 tested negative. The most important clinical variable to predict a positive swab result in non-pregnant women was age, while elevated D-dimer levels and presence of an abnormal fetal heart rate pattern were the most important clinical variable in pregnant women to predict a positive test.
Conclusion In an attempt to better understand the natural history of the SARS-CoV-2 infection we present a side-by-side analysis of clinical variables found in pregnant and non-pregnant women who tested positive for COVID-19. These clinical variables can help stratify and highlight those at risk for SARS-CoV-2 infection and shed light on the individual patient risk for testing positive.
Design, simulation, and development of bipolar pulse forming network based Marx generator for S band backward wave oscillator
Authors: Patel Ankur , Chandra Romesh , Basak Ankan , K Senthil , Roy Amitava 
Published: September 2022

Pulse power systems have a wide range of applications, one of which is microwave generation. Microwave emission is associated with a certain time delay between the application of a high voltage pulse and the generation of the microwave signal. This time delay is known as microwave delay time, and it depends on the time period of the microwave signal being generated. As the time period of the microwave signal increases, the required input electrical pulse duration also goes up. To achieve this, a pulse forming network (PFN) based Marx generator is proposed. The Bipolar Marx generator is preferred over the uni-polar Marx generator to obtain the high voltage high current pulse. This also helps in maintaining the impedance requirement for Backward Wave Oscillator (BWO) devices that generate the microwave pulse. To the best of our knowledge, PFN based Marx generators have been developed up to 400 kV. Here, a bipolar Marx generator has been designed with ratings of 800 kV peak voltage, 10 kA peak current, and 150 ns flattop pulse duration. The design includes analytical calculations and numerical analysis by electromagnetic simulation. The triggering method to get a wide triggering range has also been discussed. The design values have also been experimentally verified, and the resulting parameters were applied to a BWO to simulate the microwave power that it can produce. A peak microwave power of ∼1 GW has been observed in the particle-in-cell simulation.
Investigation of internal resonance on widening the bandwidth of energy harvester based on a cantilevered double pendulum structure
Authors: Sun Shilong , Zheng Yulong , Wang Yufan , Zhang Xiao 
Published: September 2022

With the development of small-scale electronic elements and wireless sensor networks, energy harvesting technologies have attracted much attention because they can offer environment-friendly, long-lifetime, and no replacement requirements. However, energy harvesting techniques for collecting ultralow frequency vibrations remain a challenge because of the ultralow frequency, low excitation amplitude, and non-continuous vibrations. This study proposes an ultralow frequency broadband energy harvester based on a double-pendulum structure and cantilevered beam, which utilizes the internal resonance to widen the bandwidth of the energy harvester. The double pendulum oscillator with appropriate parameters can yield two resonance frequencies in an ultralow frequency band (from 1 to 5 Hz). The cantilevered beam can achieve 1:2 internal resonance with the double pendulum oscillator in the second resonance frequency of the double pendulum oscillator. The experiment result shows that the internal resonance vibration piezoelectric energy harvester based on a double-pendulum structure can obtain a bandwidth of 4.4 Hz under 0.4 g excitation.
Formation of Modern Chinese speech-quotativenǐ shuō‘you say’ and feedback-seekingnǐ shuō‘you tell me’
Authors: Long Haiping , Wang Xianhui , Wang Lei 
Published: September 2022

AbstractIn Modern Chinese, four construction types involvingnǐ shuōmay be distinguished. In this study, it is argued that the prosodically unseparated speech-quotativenǐ shuō(S1) develops from the prosodically separated speech-quotationnǐ shuō(S3) through a hypothesized complementation pathway which makes thenǐ shuōpredicate the matrix clause of the following content clause. Prosodically unseparated feedback-seekingnǐ shuō(S2), in contrast, develops from a prosodically separated feedback-seekingnǐ shuō(S4) via a hypothesized conjoining pathway which involves the loss of a prosodic gap between the feedback-seekingnǐ shuōpredicate and the clause that it occurs with. Contrary to the common assumption in the literature, S2 does not develop from S1. Meaning difference influences the selection of each of the two pathways, and in the source construction when an S3 or S4 is prosodically separated from the clause it occurs with, it is not the matrix clause of the latter. The account given in this study may also be used to explain the formation of English parenthetical predicateyou say.
Understanding the effect of nitrosylation on dynamics of human epidermal growth factor: a µs simulation study
Authors: Razzokov Jamoliddin , Fazliev Sunnatullo , Erkinova Dinora , Mamatkulov Shavkat , Chen Zhitong 
Published: September 2022

Abstract
Advancements in plasma science, such as the development cold atmospheric plasmas made it possible to easily generate reactive oxygen and nitrogen species (RONS) and apply them onto biological media at ambient conditions. Studying the interactions of RONS with biomolecules is a central topic of plasma medicine. One of the main targets of plasma medicine is to take control over signaling proteins such as human epidermal growth factor (hEGF) which is important protein in cancer treatment and wound healing. The oxidative damage of RONS on various proteins, including hEGF, was investigated using molecular dynamics (MD) simulations. However, another effect of RONS—nitrosative damage—is left unexplored. Plasma treatment can induce substantial damage via nitrosylation by reactive nitrogen species. Thus, elucidating effects of nitrosylation on protein structures is crucial, especially in plasma medicine. Here, we perform MD simulations to explore the effect of nitrosylation on the conformation of hEGF. We carried out MD simulations with different degrees of modifications of hEGF structures to mimic short and long plasma exposure times. Our results show that the nitrosylation induces conformational changes in hEGF and the breakage of disulfide bonds which might modulate binding of hEGF with its receptor. But the structural stability of hEGF remains almost unchallenged to the nitrosative damage, even to the disruption of disulfide bonds. The results assist plasma medicine applications in cancer treatment and wound healing by modulating plasma treatment time and chemical compositions of plasma-generated RONS to mediate effective oxidation of biological environment and develop optimal treatment protocols.
Low energy effective theory for axion strings
Authors: Dine Michael 
Published: September 2022

Abstract
We consider aspects of the low energy (classical) effective field theory description of
global cosmic strings. In the non-relativistic limit, we study the extent to which these are
described by the combination of the Nambu-Gotto and Kalb-Ramond actions. While in a formal sense
this is the case for infinitely long strings, for more realistic situations, the collective
coordinates of the system do not provide a complete description for more than brief intervals; as
time evolves it becomes necessary to include low momentum goldstone excitations as well.
Entropy of quantum Markov states on Cayley trees
Authors: Souissi Abdessatar , Mukhamedov Farrukh 
Published: September 2022

Abstract
In this paper, we continue the investigation of quantum Markov states (QMSs) and define their mean entropies. Such entropies are explicitly computed under certain conditions. The present work takes a huge leap forward at tackling one of the most important open problems in quantum probability, which concerns the calculations of mean entropies of quantum Markov fields. Moreover, it opens up a new perspective for the generalization of many interesting results related to the one-dimensional QMSs and quantum Markov chains to multi-dimensional cases.
Refraction, diffraction and energy losses studies using Arduino and Raspberry Pi
Authors: Janek M 
Published: September 2022

Abstract
The major purpose of this paper is to present laboratory measurements for a physics foundation course that meet the needs of the physics department. Furthermore, for obvious reasons, measures should be low-cost. Arduino and Raspberry Pi are low cost and open-source platforms that include both hardware and software that can be beneficial in a physics laboratory. Because of its inexpensive cost, wide range of sensors and transducers, ease of use, and open nature, they are the optimal tool for engaging students in active and cooperative learning. Measurements based on mentioned platforms related to refraction and diffraction processes, as well as to hysteresis losses measurement, are presented.
Amplification and interaction of two optical waves with third harmonic spectral delay
Authors: Kasapeteva Z , Dakova D , Kovachev K , Kovachev L 
Published: September 2022

Abstract
In the present paper the parametric interaction between two optical waves, which are propagating in few-mode optical fibers, is investigated. This occurs under the influence of the processes of third harmonic generation, self-phase modulation and cross-phase modulation. The generation of third-harmonic or THz generation in femtosecond region is described by a system of two coupled nonlinear differential equations. A new analytical solution of this system, which characterizes the periodic energy exchange between the two waves, is found. Depending on the wavenumber mismatch Δk, the obtained result can be used for studying different optical processes of generation of signal wave in nonlinear dispersive media. The mentioned effects are strongly related to modern optical sensors, parametric amplifiers and communication systems.
Laser ring structures in step-index fibers
Authors: Slavchev V , Dakova A , Gocheva N , Bozhikoliev I , Kovachev K , Biswas A 
Published: September 2022

Abstract
The formation and propagation of optical ring structures, given by a system of amplitude equations for the components of the electric field is investigated. The calculations are made in approximation of second-order linear dispersion and self-phase modulation. New class analytical solutions, characterizing the generation and evolution of laser ring structures in optical waveguides with step-index profile and anomalous dispersion, are described in the present work. The stability of these optical formations is a result of the specific combination of nonlinearity, diffraction and angular distribution. Laser vortices have an amplitude type of singularity which appears as depolarization of the vector field in the light radiation spot.
RSSI study of wireless Internet of Things technologies
Authors: Dinev D , Haka A 
Published: September 2022

Abstract
The Internet of Things (IoT) idea now entails a dispersed collection of different sensor networks with several functions that collect data, which is then analysed and used in applications such as smart cities. These networks are capable of transmitting massive volumes of data in a relatively efficient, yet unsecure wireless environment. These applications will only succeed if is developed a dependable a low-cost real-time method for pinpointing accurate location. Power consumption is another consideration for indoor localisation. Recent wireless technologies like ZigBee, Bluetooth Low Energy (BLE) and Long Range (LoRa), use less resources, making them ideal for interior positioning. When IoT devices are utilised, these technologies are compared in terms of precision of localisation and power consumption. Tracking the Received Signal Strength Indicator (RSSI) values can be used to locate mobile sensor nodes for low-power IoT networks. The RSSI values of sensor nodes in the BLE, ZigBee and LoRa networks for IoT were explore in this study.
Simplified model of process to design the two stages gasification system for reuse of municipal waste
Authors: Šetinc Marko 
Published: September 2022

Abstract
Municipal waste largely consists of carbon, hydrogen and oxygen. Other elements are represented in smaller proportions. Mostly, this type of waste ends up in the incinerator or landfill. Re-use is limited due to the contamination of the raw material. On paper, the model is presented that enables step by step conversion of waste into synthesis gas, which is a raw material for methanol production and production of other hydrocarbons, through the gasification system. This method allows endless re-use of material, with part of the raw material being converted into energy, carbon dioxide and water. On paper, the design of the model and the efficiency of the process is presented.
Analysis of indoor environment perceptions in the smart building
Authors: Krawczyk N , Wojciechowska P 
Published: September 2022

Abstract
Thermal comfort is of fundamental importance for people staying in a closed environment. The article focuses on research on thermal comfort in a smart building. The study was performed using two methods. The first method with the Testo 400 microclimate meter, the second method with anonymous questionnaires. The microclimate meter made it possible to measure air parameters (including temperature, humidity, speed, CO2 concentration). The anonymous poll included questions about the thermal sensations vote, thermal preferences, thermal acceptability vote, air humidity and humidity preferences vote. Students from Poland, faculty of Environmental, Geomatic and Energy Engineering, participated in the study. The research showed that the respondents preferred lower thermal conditions with the temperature range from 22.4 °C to 25.1 °C. The percentage of the students who found the conditions as unsatisfactory - has exceeded the permitted 10% range.
Optimization of the operation of Drăgan-Iad hydropower development using Flower Pollination Algorithm
Authors: Tică E-I , Neagoe A , Popa F , Popa B 
Published: September 2022

Abstract
For the operation of a large hydropower development, it was imagined as optimization problem to realize an annual planned energy generation with monthly imposed fractions. It was conceived a model based on a flower pollination algorithm. Simulations were done for mean hydrological year, with imposed minimal and maximal volumes, for five initial volumes in the reservoir and in two hypotheses related to the imposed annual energy. For imposing realization of the designed energy, for the initial volume into the reservoir set to three lowest values, the planned energy is not realized because the volume into reservoir reaches the minimum allowable volume at the end of the year. For larger volumes at the beginning of the year, the planned annual energy is realized. For the planned annual energy imposed at a lower value, for the three lowest volumes into the reservoir at the beginning of the year the planned energy is realized, and for the other two larger values the program realizes a larger energy generation because, during the year, the volume into the reservoir reach the maximum allowable volume and it was compulsory to operate the hydropower plant to lower the volume. The overall conclusion of the paper is that FPA is very efficient for solving this type of optimization problem applied to a large hydropower development.
Combined electrochemical treatment coupled to anaerobic digestion effluents
Authors: Marmanis D , Emmanouil C , Thysiadou A , Fantidis J G , Kokkinos N , Diamantis V 
Published: September 2022

Abstract
Electrochemical treatment is an effective method to improve physicochemical characteristics of effluents and to minimize the environmental footprint of anaerobic digestion facilities. In the present research an anaerobic digester effluent was subjected to post-treatment, using electro-oxidation or electrocoagulation processes for significant reduction of Chemical oxygen demand and ammonia. A combined electro-oxidation and electrocoagulation treatment was also performed. Results show satisfactory decrease of both Chemical oxygen demand and ammonium nitrogen, which however were relative to the method applied, the time duration and the current intensity. A combined use of both methods may be the best solution for the post-treatment of this high burden effluent. All the presented values have occurred from experiments in the Chemistry Department of the International Hellenic University.
Verification of the Fanger model with field experimental data
Authors: Stokowiec K , Kotrys-Działak D , Jastrzębska P 
Published: September 2022

Abstract
Thermal comfort is one of the main aspect of human life due to the period of time each of us spends inside of the enclosed room on one hand as well as the health issues connected with the sick building syndrome on the other. Presently, the international standards are based on the Fanger model with calculations of proper indexes according to the inside air parameters as well as characteristics for room users. The paper presents the verification of Fanger model with experimental data obtained from research conducted in 6 classrooms of an intelligent, educational building. The measurements were acquired by means of Testo 400 meter where air parameters such as temperature or humidity were collected. For other evidence the questionnaire was prepared, where respondents presented their thermal sensation together with the information of their clothes present thermal insulation. The results proved that the Fanger model is not precise, since the findings calculated with the international standard differ from those obtained from the questionnaires.
Study of the electromechanical load of the motor-reducer group for a double drum drive of a belt conveyor
Authors: Dzhustrov K , Iliev Zh 
Published: September 2022

Abstract
The article presents a study of the electro-mechanical loading of the motor-reducer group for driving a belt conveyor. The current of the two drive motors has been measured following an emergency replacement of the reducer gear and the hydraulic clutch of the first drive unit. The traction forces in the belting generated by the two driving drums have been established. A comparison is made of the current records from this study and those from the enterprise information system. Thermal imaging photos have been taken of the two reducers and the hydraulic clutches of the drive units. The electromechanical state of the motor-reducer groups is analyzed and conclusions are drawn regarding the operation of the belt conveyor.
Influence degree of skin-effect for overhead line conductors
Authors: Sukhichev M , Skochko E 
Published: September 2022

Abstract
This paper analyzes the skin-effect influence on ACSR conductors for overhead lines. The analysis is based on numerical models: one cylinder, and two coaxial cylinders, and cylinders layers. The authors compare all models with each other, as well as with the well-known analytical solution, and direct current mode. All numerical models were verified by comparison with the analytical solution. The results show the one cylinder model get incorrect results for ACSR conductors. Moreover, the maximum error about 40% is given by conductors with a medium cross-sectional area, such as the ”AC 240/39” conductor by GOST 839-2019. The two coaxial cylinders model gives better results but about 10% less than the cylinders layers model, since it does not consider the electric field penetration between wires of a conductor. As a result, the authors conclude that the skin effect has a great influence for all ACSR conductors.
Dynamical symmetry algebras of two superintegrable two-dimensional systems
Authors: Marquette I , Quesne C 
Published: September 2022

Abstract
A complete classification of 2D quadratically superintegrable systems with scalar potential on two-dimensional conformally flat spaces has been performed over the years and 58 models, divided into 12 equivalence classes, have been obtained. We will re-examine two pseudo-Hermitian quantum systems E
8 and E
10 from such a classification by a new approach based on extra sets of ladder operators. They correspond in fact to two of those equivalence classes. Those extra ladder operators are exploited to obtain the generating spectrum algebra and the dynamical symmetry one. We will relate the generators of the dynamical symmetry algebra to the Hamiltonian, thus demonstrating that the latter can be written in an algebraic form. We will also link them to the integrals of motion providing the superintegrability property. This demonstrates how the underlying dynamical symmetry algebra allows to write the integrals in terms of its generators and therefore explains the symmetries. Furthermore, we will exploit those algebraic constructions to generate extended sets of states and give the action of the ladder operators on them. We will present polynomials of the Hamiltonian and the integrals of motion that vanish on some of those states, then demonstrating that the sets of states not only contain eigenstates, but also generalized states which are beyond the well-known eigenstates of diagonalizable Hamiltonians and satisfy more complicated polynomial identities. Our approach provides a natural framework for such states.