bluuebunny/crossref_metadata_2025 huggingface dataset:
Developing a correction factor to apply to animal–vehicle collision data for improved road mitigation measures
Authors: Lee Tracy S. , Rondeau Kimberly , Schaufele Rob , Clevenger Anthony P. , Duke Danah
Published: April 2021

Abstract Context Road mitigation to reduce animal–vehicle collisions (AVCs) is usually based on analysis of road survey animal carcass data. This is used to identify road sections with high AVC clusters. Large mammals that are struck and die away from a road are not recorded nor considered in these analyses, reducing our understanding of the number of AVCs and the cost–benefit of road mitigation measures. Aims Our aim was to develop a method to calculate a correction factor for large mammal carcass data reported through road survey. This will improve our understanding of the magnitude and cost of AVCs. Method Citizen scientists reported animal carcasses on walking surveys along transects parallel to the highway and reported observations using a smartphone application at three sites over a 5-year period. These data were compared with traditional road survey data. Key result We found that many large mammals involved in AVCs die away from the road and are, therefore, not reported in traditional road surveys. A correction factor of 2.8 for our region can be applied to road survey data to account for injury bias error in road survey carcass data. Conclusions For large mammals, AVCs based on road survey carcass data are underestimates. To improve information about AVCs where little is known, we recommend conducting similar research to identify a correction factor to conventionally collected road survey carcass data. Implications Identifying road mitigation sites by transportation agencies tends to focus on road sections with above-threshold AVC numbers and where cost–benefit analyses deem mitigation necessary. A correction factor improves AVC estimate accuracy, improving the identification of sites appropriate for mitigation, and, ultimately, benefitting people and wildlife by reducing risks of AVCs.
Establishment of bovine expanded potential stem cells
Authors: Zhao Lixia , Gao Xuefei , Zheng Yuxuan , Wang Zixin , Zhao Gaoping , Ren Jie , Zhang Jia , Wu Jian , Wu Baojiang , Chen Yanglin , Sun Wei , Li Yunxia , Su Jie , Ding Yulin , Gao Yuan , Liu Moning , Bai Xiaochun , Sun Liangzhong , Cao Guifang , Tang Fuchou , Bao Siqin , Liu Pentao , Li Xihe
Published: April 2021

Significance

Bovine embryonic stem cells and pluripotent stem cells hold the potential to substantially advance biotechnology and agriculture. We report the establishment of bovine expanded potential stem cells (bEPSCs) from preimplantation embryos of both wild-type and somatic cell nuclear transfer (SCNT). EPSCs have broader developmental potential to generate embryonic and extraembryonic cell lineages. bEPSCs express high levels of pluripotency genes, propagate robustly in single cell passaging, are genetically stable, and permit efficient precise gene editing. They differentiate in vitro and in chimeras to both the embryonic and extraembryonic cell lineages. Importantly, genetically modified bEPSCs can be used as donors in SCNT or cloning.
Baccharis pilularis (coyote brush).
Authors: Palmer Bill
Published: April 2021

A datasheet on Baccharis pilularis covering, as an economically important tree, its taxonomy, importance, silviculture, distribution, biology and ecology, uses, products and pests.
Effects of attaching elastic bands to the waist and heels on drop jumps
Authors: Peng Hsien‐Te , Song Chen‐Yi , Chen Zong‐Rong , Lai Chien‐Ting , Gu Chin‐Yi , Wang Li‐I.
Published: April 2021

This study aimed to investigate the effects of the external load of elastic bands attached to the waist and heels to enhance the pre‐activation of leg extensor muscles on drop jumps (DJs). Twelve male college athletes volunteered for this study. Eight cameras and two force platforms were used to collect data. Each subject performed DJs with elastic band loads of 0% and 20% body weight (BW) attached to the waist and heels during the airborne and landing phases from 40‐ and 50‐cm drop heights. Repeated measures of two‐way analysis of variance were performed with two loads of the elastic bands and two heights of the platform for each dependent biomechanical variable. Jump height, reactive strength index, leg stiffness, hip, knee flexion, and ankle plantarflexion angles at the initial foot contact and ankle dorsiflexion range of motion (ROM) significantly increased with 20% BW loads. The peak ground reaction force of impact, eccentric work, and hip flexion range of motion significantly decreased with 20% BW loads. The use of the elastic bands as accentuated loading during the airborne and landing phases of DJs can induce pre‐activation of the joint extensors of the lower extremity to achieve stretch‐shortening cycle benefits and performance and reduce the ground impact for the lower extremity.

Highlights

Attaching elastic bands to the waist and heels enables the following during drop jumps.

The joint extensors of the lower extremities act as a counterbalance to the pull from the elastic bands.

The performance of the drop jump was improved.

The ground impact was reduced.
Proton radioactivity within the generalized liquid drop model with various versions of proximity potentials
Authors: Xin Yu-Qi , Deng Jun-Gang , Zhang Hong-Fei
Published: April 2021

In the present work, we systematically investigate the proton radioactivity half-lives of spherical proton emitters adopting a generalized liquid drop model (GLDM) with 16 different proximity potentials, of which the proximity potential Prox.77-13 gives the closest results to the experimental data. Combined with the previous conclusion that the GLDM with proximity potential Prox.77-13 can also best describe α decay half-lives, which makes the model more uniform and consistent. Further, we use the proximity potential Prox.77-13 in GLDM to predict the proton radioactivity half-lives of 14 spherical proton emitters that are allowed energetically but not yet observed experimentally or specifically quantified. Finally, we research the Geiger−Nuttall law for proton radioactivity. The results reveal that the Geiger−Nuttall law can also be well used to study the proton radioactivity half-lives of isotopes with the same orbital angular momentum l.
Prediction of Heart Diseases using Random Forest
Authors: Pal Madhumita , Parija Smita
Published: April 2021

The process of discovering or mining information from a huge volume of data is known as data mining technology. Today data mining has lots of application in every aspects of human life. Applications of data mining are wide and diverse. Among this health care is a major application of data mining. Medical field has get benefited more from data mining. Heart Disease is the most dangerous life-threatening chronic disease globally. The objective of the work is to predicts the occurrence of heart disease of a patient using random forest algorithm. The dataset was accessed from Kaggle site. The dataset contains 303 samples and 14 attributes are taken for features of the dataset. Then it was processed using python open access software in jupyter notebook. The datasets are classified and processed using machine learning algorithm Random forest. The outcomes of the dataset are expressed in terms of accuracy, sensitivity and specificity in percentage. Using random forest algorithm, we obtained accuracy of 86.9% for prediction of heart disease with sensitivity value 90.6% and specificity value 82.7%. From the receiver operating characteristics, we obtained the diagnosis rate for prediction of heart disease using random forest is 93.3%. The random forest algorithm has proven to be the most efficient algorithm for classification of heart disease and therefore it is used in the proposed system.
A LiDAR System Simulator Using Parallel Raytracing and Validated by Comparison with a Real Sensor
Authors: Gusmão G F , Barbosa C R H , Raposo A B , de Oliveira R C
Published: April 2021

The advances in 3D imaging and Computer Vision are allowing for a massive acquisition of data, especially in the form of point clouds. However, scanning with these sensors can be costly and time consuming, reducing the efficiency of certain procedures, like deep learning dataset generation and forest canopy calculation. One trending solution is the creation of 3D imaging sensor simulators. This paper presents a simulator for light detection and ranging (LiDAR) systems with a parallel raytracing approach and a flexible scene creator. Finally, the simulator sensor is validated with a real LiDAR data.
Evaluating of the ultrasonic transducers’ diameter on velocity measurement in nondestructive testing
Authors: Dourado T C , Miqueleti S A , Alvarenga A V , Costa-Félix R P B
Published: April 2021

Nondestructive test (NDT) has been proved to be a valuable support for industry, saving money and time. International standards provide some requirements for transducers’ diameter concerning the area section of the workpiece to be inspected. This paper investigates the relationship between the ultrasonic transducer’s diameter and the area section to be measured, and its impact on the measured longitudinal ultrasonic velocity. Initial results showed a tendency of growth on the ultrasonic velocity with an increase of diameter.
Multiparametric measuring system for atmospheric monitoring
Authors: Cavalcante T L , Louzada D R , da Silva A , Monteiro E C
Published: April 2021

There are several studies in the literature on monitoring carbon dioxide concentrations in combination with various other parameters to assess indoor air quality. However, no study describes the monitoring of air quality in different locations of the same environment. The characterization of the spatial distribution of atmospheric parameters can contribute to more appropriate analyses, providing customized planning’s for improvements. The present work develops a multiparametric measuring system for real-time monitoring of the spatial distribution of carbon dioxide, temperature, humidity, particulate matter, volatile organic compounds, and barometric pressure. Preliminary results indicate the necessity of multiple-location measurement for appropriate air quality analyses.
Proposed model for legal control applied to stand-alone meters and measuring systems for crude oil
Authors: Junior Edisio Alves de Aguiar
Published: April 2021

The joint resolution ANP/Inmetro 001/2013 approves the Technical Regulation for Oil and Natural Gas Measurements, establishing the technical, constructive and metrological conditions and requirements that oil and natural gas meters and measuring systems must comply, to ensure the credibility of the measurement results. This is a singular regulation in the field of legal metrology in Brazil, and this study presents technical details that may justify the possibility of implementing differences between the legal control of meters and measuring systems used on the crude oil production. Emphasis is given to the singleness of the measuring systems employed on oil platforms, designed for unique installation conditions, on specific platforms, which limit the possibility of presenting a “prototype”, a common practice in the control of serial manufactured instruments. The possibility of a project type approval model, presented by the metering station developer is suggested.
Metrological control of electrolytic sensors for measuring angular deviations: application in monitoring displacements of engineering structures
Authors: Leaño E G , Rocha Filho P , Hernández J D , Frota M N
Published: April 2021

The work evaluates the metrological reliability of electrolytic sensors (electrolevels) used to determine angular deviations of elements of engineering structures. The motivation for the work resulted from its strategic application to control the stability of civil engineering structures, notably with application in geotechnics (e.g.: different types of dams of interest in engineering). The methodology used is based on the metrological consistency associated with the quality control process of a set of electrolevels submitted, simultaneously, to a careful calibration process, with traceability ensured to a standard angular deviation pattern. Mounted on a rigid bar, but pivoted at one of its ends to allow angular displacements, the output of each electrolevel is compared with the previously calibrated standard, for different controlled conditions of angular deviation imposed on the bar articulated to a center of rotation. The result of the analysis of typical calibration data for nine electrolevels allowed to show that the expression of the uncertainties associated with the calibration measurements performed constitutes an essential foundation to ensure the metrological reliability of the electrolevels, having allowed to validate a method of discard of electrolevels not meeting the allowable tolerance for a specific engineering application. Among the conclusions of the work, it was possible to qualify the statistical treatment of the levels of uncertainty as a sufficiently robust strategy to validate the electrolevels as a reliable instrument for angular displacement measurements, with a level of confidence appropriate to its application in civil engineering.
Characterization of ABS + W and ABS + Bi 3D printing filaments attenuation for different photon beams
Authors: Villani D. , Savi M. , Andrade M. A. B. , Campos L.L. , Potiens M. P. A.
Published: April 2021

3D printing techniques and materials have become widely available in the last couple of decades and remains a hot topic of study as new materials can lead to new applications. This study aims to evaluate the attenuation behaviour of GMASS over photon beams ranging from 29.7 up to 661.7keV, comparing with pure ABS and using theoretical data of pure lead as reference. It was used the transmission method to obtain experimental attenuation coefficients to all materials and theoretical data. HVL and TVL calculations were also performed. Results show that ABS+W has higher attenuation than ABS+Bi and pure ABS. Using the lead theoretical reference data it can be concluded that although ABS+Bi and ABS+W attenuates less than pure lead, the 3D printing filaments can be used to create shielding tolls depending on radiation energy and application.
Entrance Skin Dose Evaluation in Pediatric Patients Undergoing Skull, Pelvis and Abdomen Radiographs
Authors: Vosiak P , Schelin H R , Bunick A P , da Silva J L C , Nicolodelli M A
Published: April 2021

X-rays are widely used in medicine, including pediatrics. In addition to the benefits offered by the diagnosis, its use may also lead to the occurrence of biological effects. In pediatrics some tissues or organs are more radiosensitive. Also, due to the small size of the children, the organs are very close, increasing the radiation dose received by the patients. This study aimed to estimate the radiation dose received by children in the Skull AP, Abdomen AP and Pelvis AP projections. The dose calculation was performed from the x-ray tube output and the values were compared with major international dose reference levels. The results differ slightly from those presented by the adopted reference levels, but still are within the proposed range. The same happens for the radiographic technique used in each exam studied.
Garfield++ simulation of a TH-GEM based detector for standard mammography beam dosimetry
Authors: Silva Natália F. , Silva Tiago F. , Castro Maysa C. , da Luz Hugo N. , Caldas Linda V. E.
Published: April 2021

The TH-GEM based detector is a robust, simple to manufacture, high-gain gaseous electron multiplier. Its operation is based on a standard printed circuit board (PCB) coated on both sides by metallic material, perforated in a millimeter pattern, and immersed in gas. In order to study the feasibility of using TH-GEM type detectors in dosimetric applications for standard mammography beams, a prototype with adequate dimensions and materials was produced. The present work encompasses the calculations of electric fields by the Gmsh and Elmer software packages and the avalanche simulation using Garfield++ library of a TH-GEM detector filled with Ar/CO2 mixture at atmospheric pressure.
Monte Carlo Method and Their Codes Applied to Ionizing Radiation
Authors: Nascimento M , Peixoto J
Published: April 2021

The Monte Carlo method is a tool of high importance in the contemporaneous context. Not only does its statistical approach allow estimating integrals and differentials equations that do not have an analytical solution, as it also allows that events of stochastic nature can be simulated. In this context, it will be explored the use of the method in the universe of ionizing radiation as a foundation of a project looking for the implementation of a metrology 4.0. In this sense, the following codes will be explored: GEANT4, EGSnrc, PENELOPE and MCNP exhibiting vantages and disadvantages concerning their use.
Software for mobile devices to support the environmental radiological monitoring
Authors: Gonzalez S A , Silva P A , Almeida Silva T A
Published: April 2021

Project to develop a software for mobile devices where the samples collected for the purpose of environmental radiological monitoring can be cataloged and analyzed by researchers involved in radioprotection and nuclear safety procedures.
CCT determination using a method with automated iterative calculation
Authors: Ázara I , Menegotto T , Gomes J
Published: April 2021

Correlated Colour Temperature (CCT) of light sources has been usually determined using the Robertson’s method, that is based on a table with values of chromatic coordinates corresponding to various values of the blackbody locus in the CIE u,v diagram. Robertson’s method requires interpolation, normally linear, that led to an acceptable accuracy but that could be improved. The proposed method is based directly on the CCT as defined by the CIE. It allows a better accuracy, in the determination of CCT and Duv, that is the distance of the chromaticity to the blackbody locus in the CIE u,v diagram. The Excel® Solver resource is used, and the method permits easily updating the universal constants to the recently defined values by the BIPM.
Practical considerations for OCT applications
Authors: Cordes A H , Couceiro I B , Alvarenga A D , Malinovski I , Dominguez C T , de Andrade C V , Russomano F B , von der Weid J P
Published: April 2021

OCT measurements have a fundamental trade-off between the ability to resolve small details and the range over which the measurement is consistent. A measurement which is able to resolve small details is able to do so over a small range. A measurement which is consistent over a larger range is not able to resolve small details. While the axial resolution of the OCT measurement is determined by the optical bandwidth of the source, the lateral resolution (spot size) is determined by the focusing optics and the characteristics of the Gaussian beam. The spot size and the depth of field of a Gaussian beam are directly related in such a way that there is a trade-off between the spot size (details which can be resolved) and depth of field (distance over which the spot size is maintained). In this paper we analyze and discuss in detail the trade-off between the spot size and depth of field in OCT measurements. Some techniques to mitigate this limitation are mentioned and one is applied to measurements of cervical tissue with and without cervical intraepithelial neoplasia (CIN).
A Low-cost System for High-frequency Solar Imagery and Power Data Acquisition
Authors: Bassous G F , Calili R F , Barbosa C R H
Published: April 2021

With advances in solar energy research and increasingly accurate forecast techniques, intermittency no longer stands as a barrier to the adoption of solar energy. Coupling reliable data and knowledge on the inherent variability of the solar resource with advanced learning and forecast models, renewable energy can take an even bigger role in today’s energy paradigm. The objective of this work is to develop and test a low-cost data acquisition system able to provide relevant data for solar energy forecast models. The results yielded from the performed tests indicate high correlation between image derived attributes and power measurements 20 s ahead.
Advance in the development of wideband resistive voltage dividers
Authors: Slomovitz D , Trigo L , Faverio C , Kyriazis G A
Published: April 2021

The advance in the development of a set of resistive dividers is described. The frequency range is 50 Hz to 100 kHz and the voltage, from 4 V to 1024 V. It was used a special design for reducing the stray capacitances and to limit the temperature, especially for the highest voltages. Tests on frequency response, ratio and phase, are shown in this paper.
Credit card size computer Stratum 1 NTP Server
Authors: Damaceno L P , Mascarin R P , Müller S T , Magalhães D V
Published: April 2021

Considering the increasing number of IoT devices, internet-connected computers, smartphone devices, and connected industries, time is an important point to be taken into account. To confidently correlate data from all these devices, time synchronization with a common and global reference (TAI and UTC) is crucial. To provide to internet users our timescale and the benefits of having a traceable cesium frequency standard to BIPM, we assembled a Stratum 1 NTP server with a credit card size computer.
Estimation of the measurement uncertainty in the tests of electric distribution transformers filled with insulating liquid -no load loss and in load loss
Authors: Barbosa Vitor Martins , Landim Regis Pinheiro
Published: April 2021

Considering the lack of a method for comparison and evaluation of the tests of electric distribution transformers filled with insulating liquid, we propose a mathematical modelling of the measurement uncertainty on the losses, no load and in load. The mathematical modelling was developed using as theoretical references the Guide to Expression of Uncertainty of Measurement - ISO GUM, the ABNT NBR 5356:2007 standard and Regulatory Ordinances issued by the National Institute of Metrology, Quality and Technology - Inmetro. The models were applied to the test data of transformers as a way to assess their consistency. The measured uncertainties (k = 2) obtained from the tests for no load and in load were, respectively, U(WNLL) = 0.62 W and U(WILL) = 0.60 W.
Polymorphism of GSTM1,GSTT1,GSTP1, and GSTA1 genes In Iraqi Population
Authors: Al-Rubae’i S H N , Muftin N Q , Yaseen N Y
Published: April 2021

One of the phase II enzymes that are responsible for detoxification of the body are Glutathione S-transferases (GSTs). Type and frequency of polymorphism of GSTs differ among the population. The current paper was designed to detect the polymorphisms in GSTM1, GSTT1, GSTP1 and GSTA1 genes among the Iraqi population, and the results were compared with other population. Data will be collected in the future to obtain a genetic map of the Iraqi population. To our knowledge, this study is the first done on the Iraqi population. In this study blood samples were collected from 110 healthy individuals (51 males and 59 females) aged between 15-50 years. The presence or absence of GSTM1 and GSTT1 genes was identified by multiplex-PCR. In addition, PCR-RFLP was used to detect polymorphism of GSTP1 (Ile105Val) and GSTA1 (A*/B*). The study revealed the frequencies of GSTM1 null, GSTT1 null, GSTP1 (Ile105Val), and GSTA1 A*/B* were 34.55%, 25.45%, 45.46%, and 41.82% respectively. The most frequently observed combinations were GSTM1 Present/GSTT1 Present/Ile/Val/A*/A* (18.18%). For the first time in Iraq by this study, four sequences were recorded in NCBI under the following accession numbers LC081235.1, LC090205.1, LC081236.1, and LC090206.1. These findings provide us the basic data for genotypes distribution and allele frequencies of GSTM1, GSTT1, GSTP1 and GSTA1 in the Iraqi population, and this is open a new prospect for further investigations by researchers in identifying differences between individuals in the genetic susceptibility of various diseases caused by environmental gene, rather than depending on results obtained from other populations.
Biosorption to removing heavy metals from wastewater
Authors: Hussain S A. , Hasan N K , Al-Abodi E E
Published: April 2021

In this research, the efficacy of walnuts shell as bio adsorbent surface has been evaluated in the process of heavy elements removing from aqueous solution. Heavy metals concentrations are determined using X-ray fluorescence (XRF) techniques in walnuts shell and using the atomic absorption spectrometer to determined heavy elements concentrations in wastewater from the southern Rustumiya station, as Chromium (Cr), Nikel (Ni), Zinc (Zn), Copper (Cu), Mercury (Hg), Cadmium (Cd) and Lead (Pb). XRF technique is a viable and precise for analyzing a variety of harm materials and environmental samples with different advantages compared with conventional laboratory analysis ways.
Synthesis and spectroscopic studies of some transition metal complexes derived from bis-2-pyrazoline ligand
Authors: Abid M N , Fahad A M , Musa T M , Ismail A H
Published: April 2021

The present work focuses on the synthesis and spectroscopic studies of some metal complexes based on a novel bis-2-pyrazoline ligand; 5-(4-(1-carbamothioyl-5-(pyridin-3-yl)pyrazolidin-3-yl)phenyl)-3-(pyridin-3-yl)pyrazolidine-l-carbothioamide. This ligand was prepared via the cyclization reaction of 3-(4-((E)-3-oxo-3-(pyridin-3-yl)prop-1-en-1-yl)phenyl)-1-(pyridin-3-yl)prop-2-en-1-one with alkaline solution of thiosemicarbazide. The resulted 2-pyrazoline ligand was identified by the FT-IR, NMR and LC-MS spectroscopes, in addition to (C.H.N.S) elemental analyses. The complexes of Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) were prepared from their metal chlorides and ethanolic solution of the prepared ligand in 10% ammonia (mole ration 2:1 M:L). The octahedral geometry for all complexes was confirmed by atomic absorption, FT-IR, UV-Visible, magnetic moments and molar conductivity measurements. The thermal stability of the prepared complexes was confirmed by the thermal gravimetric analyses and the observed results indicated that the suggested chemical structure are in agreement with other data of elemental micro-analyses and flame atomic absorption spectroscopy.
Evaluation of serum ferritin and hepcidin level and their association with obesity in Iraqi obese women
Authors: Sadiq A H , Jassim A M N
Published: April 2021

Obesity is a chronic disease renowned as a global epidemic. Prevalence of obesity proceeded as highly elevated to almost two-thirds of the world population, including Iraq. One of the major reasons of overweight and obesity is increasing food intake. Obese people are often suffering from chronic inflammatory state due to a variation in immune efficiency in the adipose tissue. Our research aims to assess the ferritin and hepcidin level in obese women with and without hypertensive. Eighty of obese women were participants as volunteers, as well as, 40 subjects as healthy control. Based on Body Mass Index (BMI), Waist Circumference (WC), Waist to Height Ratio (WHtR) and Waist to Hip Ratio (WHpR). Participants were divided into two categories, the: first with BMI ≥ 18.5-25 kg/m2 as non-obese (control) and the, second with BMI ≥ 30kg/m2 as obese subjects. The studied parameters showed the following results: A significant elevation in TG, LDL, VLDL, glucose, AST, ALT, calcium, Creatinine, Uric acid, Urea, ferritin and hepcidin in obese (for both obese women and hypertensive obese women) compared with control group, while a significant decrease was noticed in HDL level in obese group as compared with control group. This study improved that ferritin and hepcidin can be considered as good markers to monitoring obesity, showing a high increase with increasing BMI.
Renalase: Gene polymorphism and its association with hypertension in some diseases
Authors: Muftin N Q , Al-Garawi Z S , Tahir N T , Tahir Z A
Published: April 2021

Hypertension is a significant public health problem due to its high prevalence and association with increased risk of cardiovascular disease (CVD), and thus the major cause of death in developed countries. Most of diabetes mellitus and hemodialysis patients are expected to have hypertension and of around 10% of pregnant women have hypertension, which increases preeclampsia; the most important medical problem that threatened the life of maternal and neonatal. Previous studies showed that genetic factors could play an important role in predicting hypertension. Recently, a novel soluble flavin adenine dinucleotide (FAD)-dependent amine oxidase, called renalase, found to decrease blood pressure by degrading catecholamines. It is secreted by the kidney and is found in the heart, small intestine, skeletal muscle, endothelium, and nervous system. Renalase polymorphism of the renalase gene may affect the renalase activity and increase susceptibility to some diseases. This review highlights the structure, function, polymorphisms of renalase, and its association with hypertension in hemodialysis, cardiovascular, preeclampsia, and diabetes mellitus patients. As a conclusion, the rs10887800, rs2576178, and rs2296545 renalase gene polymorphism could thus be a risk factor for hypertension.
Synthesis of steroid bearing heterocyclic derivatives and biological activity. Review 2014-2020
Authors: Farhan A M , Alshamusi Q K , Jebur M H
Published: April 2021

Steroidal building blocks have drawn research groups attention in many branches of science and technology, such as pharmacological and medical fields, supramolecular chemistry and compounds in nanotechnology, So the recent years have witnessed a wide focus of research directed towards preparing heterocyclic derivatives fused with steroid molecules as a result of the great biological activity these compounds, This review described an outline of the literature reports (2014-2020) of synthesis heterocyclic compounds for steroid molecules fused at rings-A or B or D of steroid skeleton or annealed, Also the review included the biological activity of steroid hetero cyclic as anti breast cancer, anti prostate cancer, antioxidant and antimicrobial.
Chemistry and synthesis of Bis Pyrazole derivatives and their biological activity: a review
Authors: Rodhan W F. , Kadhium S S. , Ali Z Z M , Eleiwi A G , Abbas R F , Mohamed I R , Hussein Z A
Published: April 2021

Pyrazole derivatives were used for all kinds of biological celerity like used for a core structure in a large of compounds that possess important pharmacological agents such as a potent anti-inflammatory, anti-obesity drug rimonabant, antitumor and analgesic. Various bis-pyrazole derivatives were introduced a great contribution not only in the synthetic chemistry but also used in the healthful chemistry field. In this review, we reported the different methods have been used for synthesis of pyrazole derivatives with some of them being used in the biological field.
Effect of laser parameters on ultra-short laser processing of SiC
Authors: Angelova L , Daskalova A , Petit F , Trifonov A , Kandeva M , Stanev G , Buchvarov I
Published: April 2021

Crystalline silicon carbide (SiC) is a very attractive material in the fields of microelectronics, MEMS and biomedicine mainly due to its chemical inertness and mechanical strength. It is used for SiC MEM sensors, micro motors and resonators [1]. In the biomedical field, SiC is emerging as a promising material for additional coating of biomaterials due to its other useful properties (hardness, lightness, impermeability and good compatibility). For instance, in combination with bioglass, it is used for bone regeneration and as coating of some metal alloys, as it forms a bone-like layer on the surface upon contact with body fluids [2]. We studied the results of microporous modifications on the SiC surface irradiated by ultrashort laser pulses in view of further biomedical applications. The nanostructures were formed on the surface of a silicon carbide sample by using a regeneratively amplified Ti:sapphire femtosecond laser emitting at 800 nm. The SiC samples were irradiated as the laser light parameters (power, energy and number of applied pulses) were varied and the surface morphological changes were investigated. Modification of the topography of the silicon carbide substrates could substantially improve the bioactivity properties of this material, which, after proper laser parameters optimization, could make its biomedical application even more successful.
Stress-induced neoplasia detection in the lower part of gastrointestinal tract of rats using phthalocyanines
Authors: Agranovich I , Khorovodov Al , Kanevsky M , Genova Ts , Gisbrecht Al , Angelov I , Mantareva V , Navolokin N , Semyachkina-Glushkovskaya O , Borisova E
Published: April 2021

In this study, phthalocyanine (ZnPc, AlPc, LuPc – Pcs) compounds were employed as exogenous fluorescent markers for diagnostics of GIT adenocarcinoma in laboratorial animals (adult male rats,n= 40) after application of an experimental model of adenocarcinoma formation with metastases. The neoplastic lesions were developed under the influence of social stress and chemical stress using nitrosamines during a 9-month period of application. A significant fluorescence signal in the region of 670 – 720 nm was observed from the neoplastic lesions, which was absent in the normal mucosa. This signal is related to the fluorescence of phthalocyanines accumulated in the tumor area. The autofluorescence background covered the region of 450 – 650 nm with a maximum at 480 – 520 nm and originated mainly from protein cross-links and co-enzymes – NADH and flavins. Endogenous porphyrins fluorescence was also observed in the lesions with a maximum at 630 – 640 nm. Visually, the presence of accumulation sites of Pcs in the form of bright pink patches was observed after excitation at 405 nm, as opposed to a healthy tissue, which remained blue-violet due to the autofluorescence signal. This allows one to use the Pcs fluorescence discrimination not only in a spectroscopic mode of detection, but for imaging of the lesions investigated, which is preferable in clinical applications during endoscopic observations in humans.
Occlusal splints – changes in the muscular activity
Authors: Taneva I , Grozdanova-Uzunova R , Uzunov T
Published: April 2021

Bruxism is considered an oral parafunction of involuntary grinding and clenching of the teeth. Occlusal splints are the most common method of preventing bruxism and its consequences. Their application significantly reduces the pathologies of the dental and periodontal structures. Infrared thermography is a noncontact method of temperature measurement whereby the detector is pointed remotely at a single spot. The purpose of the study is registering by means of infrared thermography the changes in the muscular activity during the period of occlusal splint prophylaxis. In the presence of pathological changes, splint therapy aims to return the joint-muscular complex of the masticatory apparatus to normal, which is associated with the activation of the adaptive capabilities of the organism. This dynamic process is associated with a rise in temperature. When achieving balance after wearing the splints for one and three months, a decrease in the registered temperature is naturally observed due to the created preconditions for elimination of the inflammation of the joint and the overload of the muscles.
Photodiagnostics and photodynamic treatment of stem cells cultivated from human glioblastoma tumors
Authors: Zaharieva L , Borisova E , Kyurkchiev D , Tumangelova-Yuzeir K , Ivanova-Todorova E , Angelov I , Genova Ts , Kolev B , Gisbrecht A , Avramov L , Semyachkina-Glushkovskaya O , Karazapryanov P , Minkin K
Published: April 2021

Porphyrins used as photosensitizers are accumulated selectively in glioblastoma cells due to the latter heme metabolism disorders and could be used effectively for intraoperative fluorescence staining of the tumor formation and differentiation from normal brain parenchyma. The aim of this work was to investigate the photodynamic properties of 5-ALA/PpIX on stem cell cultures isolated from glioblastoma. Supernatant samples of photosensitizer-treated cell lines were used for evaluation of photosensitizers’ accumulation in the cell lines investigated using excitation in the spectral ranges of Soret’ band (360 – 410 nm) and Q-band (600 – 650 nm). The emission detected was used to evaluate the efficacy of the photodynamic treatment during PDT irradiation inducing apoptosis and necrosis processes in cell lines treated with photosensitizers. Several variables were studied, such as histochemical and genetic variants of glioblastoma, and various photosensitizers’ concentrations and light-emitting parameters. The results of this in vitro work will be used as the basis for a further in vivo application on animal models of glioblastoma with applying irradiation using intracranial light sources and for a subsequent transfer of the obtained protocols of photodynamic treatment of glioblastoma lesions in such model systems for the needs of human medicine.
Optical control of high-density alkali atom vapor in antirelaxation coated cells
Authors: Tsvetkov S , Gateva S , Mariotti E
Published: April 2021

In this work, we report on our investigations on LIAD (Light Induced Atomic Desorption) aimed at achieving high density of alkali atoms vapor in a coated cell at room temperature. The experimental results show the possibility to reach a density up to the limit when the medium becomes optically thick by applying highly efficient homogeneous illumination. The photon reabsorption mechanism prevents the precise evaluation of the density by measuring the absorption of a probe laser beam, but there is clear evidence that densities can be achieved higher by two orders of magnitude than the thermodynamic equilibrium value.
High-beam-quality sealed-off master oscillator – power amplifier system oscillating in the visible spectral range on atomic copper transitions for micromachining in research and technology
Authors: Kostadinov I K , Astadjov D N , Yankov G P , Popova L T , Slaveeva S I , Fedchenko Yu I , Temelkov K A
Published: April 2021

High-beam-quality sealed-off master oscillator – power amplifier system is developed and studied based on a copper bromide vapor laser and oscillating on atomic copper self-terminating transitions. A detailed study on the laser beam divergence is carried out demonstrating the capability of CuBr vapor laser systems to emit diffraction-limited laser beams. Precise microprocessing of various materials, such as optical grade fused quartz, Si, stainless steel, is also implemented.
Longitudinal radiation force of laser pulses and nonlinear optics of moving neutral particles
Authors: Kovachev L M
Published: April 2021

For a long time, transverse and longitudinal optical forces have been used for non-contact manipulation of small individual particles. The following question arises: What is the impact of these forces on an ensemble of a thousand particles in continuous media? The aim of this work is to find analytical expressions of the radiation force and potential densities arising from a laser pulse propagating in dielectric media. This allows us to find an effective averaged longitudinal real force at the level of the laser pulse spot. The force obtained is proportional to the initial pulse energy and inversely proportional to its time duration. In the femtosecond region, the force becomes strong enough to confine neutral particles into the pulse envelope and translate them with the group velocity in gases. In solids, as silica for example, the longitudinal force of a femtosecond pulse is significantly greater than the molecular forces. Thus, the fine ablation in silica with short pulses may be due to this longitudinal force, which breaks down the molecular bonds. Additionally, after confinement into the pulse envelope, the moving particles produce new linear and nonlinear effects.
Enhancing fault tolerance of wireless sensor networks by changing topology
Authors: Xin Qiangwei , Guo Xinming
Published: April 2021

Wireless sensor networks work by multi hop mode. The increase of intermediate forwarding nodes will bring the packet loss rate increase. In addition, a node which has fault will affect the entire link work. The average number of forwarding node influences the fault tolerance of wireless sensor networks. In order to ensure that wireless sensor networks can work smoothly and prolong the lifetime, the reducing of average number of forwarding node is necessary, namely reducing the average number of hops. The reducing of average hop number of whole network also reduces the packet loss rate and the energy consumption of nodes. The proposed algorithm in this paper cuts down the hops and improves the fault tolerance of wireless sensor networks.
A Study on Brand Visual Design Based on Internet Technology
Authors: Yang Zhe , Zhang Ziyan
Published: April 2021

The Internet era has brought great changes to people’s lives, it promotes the continuous development of the economy, but also promote the overall upgrade of the brand, so that the brand visual image communication has more media. Under the era of the Internet technology development, the requirement of brand visual design is higher than before, it can not only limited to the visual level, at the same time it has to combine with modern new way of media communication based on the brand culture, and to enhance brand experience. Brand visual design can be feasible, at the same time promoting the development of brand implementation. This paper will mainly discuss the development path of brand visual design under the background of Internet.
Research on Online Platform of Multimedia Teaching Based on Network Engineering
Authors: Chen Xiaoxu , Li Nan
Published: April 2021

With the rapid development of the Internet, the business models of all walks of life have changed a lot, and the application of multimedia technology and network technology has become more and more extensive. In the current educational environment, the traditional one-to-one teaching model no longer exists. Multimedia technology and network technology have been widely used in the teaching process. It has established a new teaching environment for distance education institutions, making the online teaching platform more convenient and realizing more possibilities.
Traffic Flow Forecasting Analysis based on Two Methods
Authors: Liu Yingxin , Zhang Na , Luo Xinggang , Yang Min
Published: April 2021

Along with the rapid growth of China’s economy and the continuous improvement of the national living standard, the number of private cars traveling on the road is gradually increasing, and the traffic congestion problem has become the focus of people’s attention. In order to solve this big problem, the most important thing is to improve the development of public transportation, conduct scientific and reasonable public transportation scheduling, and realize the green transportation. The prediction of public transportation information is the key point of public transportation scheduling. In this study, the part of public transportation information, traffic flow, is selected for research, and the collected historical information is preprocessed and characterized. Using the weather factor as the input characteristic, the historical traffic flow is divided into 15-minute interval and 1-hour interval data sets, and two models, gradient boosting decision tree and wavelet neural network, are used to predict the traffic flow of road sections. The experimental results show that the gradient boosting decision tree model based on the 15-minute interval has high prediction accuracy and good generalization performance.
Research on Disambiguation Attributes Based on Semantic Hierarchical Model
Authors: Yu Linlin , Wang Zhenxia , Su Li , Wei Dan
Published: April 2021

Feature extraction concepts and statistical classifiers began to be used in computer-aided detection and diagnosis, and many different feature learning techniques such as principal component analysis, image block clustering and dictionary methods are very popular. However, in the case of less labeled data, the application and effect of deep learning are restricted. The research content of this paper is based on items such as nodule multi-semantic and fine-grained classification and rating research of WGAN synthetic oversampling learning, multi-semantic assisted disambiguation research based on multi-level association transfer learning, and multi-label incremental learning research for small sample semantic hierarchical structure. Moreover, based on the synthesis of various semantic samples, multi-semantic association transfer, and multi-label incremental learning methods, a set of effective methods and application mechanisms for intelligent auxiliary semantic hierarchical structure disambiguation are formed by describing the problem definition, proposing research methods, and discussing the experimental effects of the proposed methods in detail.
Automatic segmentation of retinal edema in optical coherence tomography based on deep neural networks
Authors: Lu Rongrong , Wang Lidan , Duan Shukai
Published: April 2021

A multi-task network framework based on convolutional neural networks improvements is proposed for automatic segmentation and classification in three different lesion areas of retinal OCT images. We propose a dilated convolutions module to capture fine-grained semantic information and introduce dense skip connections to integrate features of multiple scales and different semantic levels. Furthermore, we use a joint loss function that balances the relative size of the data labels and the improved generalization of the network. The validity and reliability of our proposed method are trained and verified on OCT datasets. Extensive experimental results demonstrate that the average Dice coefficient of the three lesion areas is 2.61% higher than the most commonly used U-net model in the field of medical image segmentation and reaches 0.81501.
Sememe-based Topic-to-Essay Generation with Neural Networks
Authors: Luo Dan , Ning Xinyi , Wu Chunhua
Published: April 2021

Topic-to-Essay generation task aims to generate topic related and coherence text based on user input. Previous research generates text solely based on the input words and the generation results in not satisfactory. The traditional methods using semantic relationships of words from corpus to guide the model, which made the model rely heavily on the corpus. In this paper, we propose a sememe-based topic-to-essay generation model(S-TEG), which integrates sememes from external knowledge graph HowNet with input topic words to guide the model. In order to prevent introducing noise, we elaborately devise measuring the similarity of the non-current topic words to filter sememes information. The experiment results demonstrate that our approach achieved 4.10 average score in subjective evaluation and a 3.60 BLEU score, which shows that our model is able to generate text that is more coherence, topic-related and fits the daily logic.
Evaluation and Emotional Analysis of Mobile Phone Sales of JD E-commerce Platform Based on LDA Model
Authors: Xue Jingfeng , Li Jing , Han Yujia
Published: April 2021

With the rapid development of the Internet economy, the online transaction volume of e-commerce platforms has soared, and the purchase experience shared by users has become particularly important. How to quickly and effectively extract the required information from a large number of user reviews plays an important role in the decision-making of both consumers and businesses. This article conducts sentiment analysis on JD business platform Huawei mobile phone user comment information. First, this paper use crawler methods to collect user evaluation text information, and perform data preprocessing such as deduplication and cleaning of the collected raw data; then perform word segmentation on the processed text content, and filter stop words and worthless words; use the method based on emotional dictionary matching to analyze the sentiment tendency of the text. Finally, using the LDA topic analysis model, LDA topic analysis is performed on the sentiment classification text, and the topic words are extracted to obtain valuable internal information, and reasonable marketing strategies are proposed for the business.