bluuebunny/crossref_metadata_2025 huggingface dataset:
Principal Component Thermography for Defect Detection in Concrete
Authors: Milovanović Bojan , Gaši Mergim , Gumbarević Sanjin
Published: July 2020

The goal of the condition assessment of concrete structures is to gain an insight into current condition of concrete and the existence of defects, which decrease durability and usability of the structure. Defects are quite difficult to detect using infrared thermography when concrete elements cannot be thermally excited with the Sun, together with unfavorable thermophysical properties of concrete structures. In this paper, principal component thermography (PCT) is applied as a post-processing method to a sequence of thermograms in order to enhance defect detectability in concrete structures. Defects are detected by analyzing a set of empirical orthogonal functions (EOFs), which were acquired by applying principal component analysis to a sequence of thermograms. The research was performed using concrete samples containing known defects, which were tested using a step heating thermography setup. The results of presented research show that PCT is an effective post-processing method to improve defect detection in concrete structures. By effectively improving the defect detection, PCT has a potential to improve the non-destructive testing (NDT) accuracy of using infrared thermography (IRT) on concrete structures, especially in shaded areas of such structures. The research also shows the defect detectability depending on concrete type thermal excitation setup and defect geometry.
Evaluation and Impact Reduction of Common Mode Currents on Antenna Feeders in Radiation Measurements
Authors: Constantin Andreea , Tamas Razvan D.
Published: July 2020

Common mode currents on antenna feeders usually occur when feeding a symmetric radiator through an asymmetric line, or when the ground plane is electrically small. Such currents may have magnitudes comparable to the feed currents and therefore have a major impact on the total radiated field. For antenna radiation measurements, both assessment and reduction of the common mode currents on antenna feeders are crucial. Techniques to discriminate antenna and feeder radiation are mainly needed for design and optimization purposes. Antenna gain measurements in a multipath site can be performed by using the distance averaging method. In this paper, we show that the distance averaging technique can be applied to reduce the effect of common mode currents for measuring the field radiated by symmetrical antennas. Two measuring configurations are proposed depending on the number of symmetry degrees of the antenna under test, and a differential approach for extracting the field created by the common mode currents was also developed. The experimental validation was performed by measuring a simple wire dipole and a log-periodic dipole array (LPDA) with a small square loop as a probe, both on the feeder side and on the feeder free side.
Condition Evaluation of an Existing T-Beam Bridge Based on Neutral Axis Variation Monitored with Ultrasonic Coda Waves in a Network of Sensors
Authors: Zhan Hanyu , Jiang Hanwan , Zhang Jinquan , Jiang Ruinian
Published: July 2020

Neutral axis passing through the stiffness centroid of a structure is correlated with structural health conditions. Traditional techniques rely on gauge arrays to observe strains at their installation positions, and then locate a neutral axis through the intercept of the strain diagram. However, these localization results will be severely deviated if any damages exist among gauges or inside structures. In this paper, a novel technique is proposed to locate the neutral axis by measuring and analyzing ultrasonic coda waves in a network of transducers. Because of multiple trajectories, coda waves are sensitive to minor changes in a large volume of media that are not limited to direct paths between sensors. This technique is not only capable of locating a neutral axis with great efficiency and accuracy, but can also indicate global structural health and inner damages. The applicability of the technique is demonstrated by monitoring a 30 m concrete T-beam subjected to four-point loading tests. With an array of transducers placed at the surface, the neutral axes in the large region are located. The localization results also show clear trends that the global neutral axis moves up as the loads increase, which indicates the beam contains certain degrees of inner damage.
Deep Physiological Model for Blood Glucose Prediction in T1DM Patients
Authors: Munoz-Organero Mario
Published: July 2020

Accurate estimations for the near future levels of blood glucose are crucial for Type 1 Diabetes Mellitus (T1DM) patients in order to be able to react on time and avoid hypo and hyper-glycemic episodes. Accurate predictions for blood glucose are the base for control algorithms in glucose regulating systems such as the artificial pancreas. Numerous research studies have already been conducted in order to provide predictions for blood glucose levels with particularities in the input signals and underlying models used. These models can be categorized into two major families: those based on tuning glucose physiological-metabolic models and those based on learning glucose evolution patterns based on machine learning techniques. This paper reviews the state of the art in blood glucose predictions for T1DM patients and proposes, implements, validates and compares a new hybrid model that decomposes a deep machine learning model in order to mimic the metabolic behavior of physiological blood glucose methods. The differential equations for carbohydrate and insulin absorption in physiological models are modeled using a Recurrent Neural Network (RNN) implemented using Long Short-Term Memory (LSTM) cells. The results show Root Mean Square Error (RMSE) values under 5 mg/dL for simulated patients and under 10 mg/dL for real patients.
Temperature Stability and Spectral Tuning of Long Period Fiber Gratings Fabricated by Femtosecond Laser Direct Writing
Authors: Viveiros Duarte , de Almeida José M. M. M. , Coelho Luís , Vasconcelos Helena , Maia João M. , Amorim Vítor A. , Jorge Pedro A. S. , Marques Paulo V. S.
Published: July 2020

Long period fiber gratings (LPFGs) were fabricated in a standard single mode fiber (SMF-28e) through femtosecond (fs) laser direct writing. LPFGs with longer and shorter periods were fabricated, which allows coupling from the fundamental core mode to lower and higher order asymmetric cladding modes (LP1,6 and LP1,12, respectively). For the grating periods of 182.7 and 192.5 µm, it was verified that the LP1,12 mode exhibits a TAP at approximately 1380 and 1448 nm in air and water, respectively. Characterization of the LPFGs subjected to high-temperature thermal treatment was accomplished. Fine-tuning of the resonance band’s position and thermal stability up to 600 °C was shown. The temperature sensitivity was characterized for the gratings with different periods and for different temperature ranges. A maximum sensitivity of −180.73, and 179.29 pm/°C was obtained for the two resonances of the 182.7 µm TAP LPFG, in the range between 250 and 600 °C.
A Spatially Distributed Fiber-Optic Temperature Sensor for Applications in the Steel Industry
Authors: Roman Muhammad , Balogun Damilola , Zhuang Yiyang , Gerald Rex E. , Bartlett Laura , O’Malley Ronald J. , Huang Jie
Published: July 2020

This paper presents a spatially distributed fiber-optic sensor system designed for demanding applications, like temperature measurements in the steel industry. The sensor system employed optical frequency domain reflectometry (OFDR) to interrogate Rayleigh backscattering signals in single-mode optical fibers. Temperature measurements employing the OFDR system were compared with conventional thermocouple measurements, accentuating the spatially distributed sensing capability of the fiber-optic system. Experiments were designed and conducted to test the spatial thermal mapping capability of the fiber-optic temperature measurement system. Experimental simulations provided evidence that the optical fiber system could resolve closely spaced temperature features, due to the high spatial resolution and fast measurement rates of the OFDR system. The ability of the fiber-optic system to perform temperature measurements in a metal casting was tested by monitoring aluminum solidification in a sand mold. The optical fiber, encased in a stainless steel tube, survived both mechanically and optically at temperatures exceeding 700 °C. The ability to distinguish between closely spaced temperature features that generate information-rich thermal maps opens up many applications in the steel industry.
Toward Resilient Wireless Sensor Networks: A Virtualized Perspective
Authors: Rashid Adnan , Pecorella Tommaso , Chiti Francesco
Published: July 2020

The Internet of Things (IoT) has been one of the main focus areas of the research community in recent years, the requirements of which help network administrators to design and ensure the functionalities and resources of each device. Generally, two types of devices—constrained and unconstrained devices—are typical in the IoT environment. Devices with limited resources—for example, sensors and actuators—are known as constrained devices. Unconstrained devices includes gateways or border routers. Such devices are challenging in terms of their deployment because of their connectivity, channel selection, multiple interfaces, local and global address assignment, address resolution, remote access, mobility, routing, border router scope and security. To deal with these services, the availability of the IoT system ensures that the desired network services are available even in the presence of denial-of-service attacks, and the use of the system has become a difficult but mandatory task for network designers. To this end, we present a novel design for wireless sensor networks (WSNs) to address these challenges by shifting mandatory functionalities from unreliable to reliable and stable domains. The main contribution of our work consists in addressing the core network requirements for IoT systems and pointing out several guidelines for the design of standard virtualized protocols and functions. In addition, we propose a novel architecture which improves IoT systems, lending them more resilience and robustness, together with highlighting and some important open research topics.
Deep Learning for Feature Extraction in Remote Sensing: A Case-Study of Aerial Scene Classification
Authors: Petrovska Biserka , Zdravevski Eftim , Lameski Petre , Corizzo Roberto , Štajduhar Ivan , Lerga Jonatan
Published: July 2020

Scene classification relying on images is essential in many systems and applications related to remote sensing. The scientific interest in scene classification from remotely collected images is increasing, and many datasets and algorithms are being developed. The introduction of convolutional neural networks (CNN) and other deep learning techniques contributed to vast improvements in the accuracy of image scene classification in such systems. To classify the scene from areal images, we used a two-stream deep architecture. We performed the first part of the classification, the feature extraction, using pre-trained CNN that extracts deep features of aerial images from different network layers: the average pooling layer or some of the previous convolutional layers. Next, we applied feature concatenation on extracted features from various neural networks, after dimensionality reduction was performed on enormous feature vectors. We experimented extensively with different CNN architectures, to get optimal results. Finally, we used the Support Vector Machine (SVM) for the classification of the concatenated features. The competitiveness of the examined technique was evaluated on two real-world datasets: UC Merced and WHU-RS. The obtained classification accuracies demonstrate that the considered method has competitive results compared to other cutting-edge techniques.
A Review of the Real-Time Monitoring of Fluid-Properties in Tubular Architectures for Industrial Applications
Authors: A. Nour Maha , M. Hussain Muhammad
Published: July 2020

The real-time monitoring of fluid properties in tubular systems, such as viscosity and flow rate, is essential for industries utilizing liquid mediums. Nowadays, most studies of the fluid characteristics are performed off-line using laboratory facilities that can provide accurate results, yet they do not match the demanded industrial pace. Off-line measurements are ineffective and time-consuming. The available real-time monitoring sensors for fluid properties are generally destructive methods that produce significant and persistent damage to the tubular systems during the installation process. Others use huge and bulky invasive instrument methods that generate considerable pressure reduction and energy loss in tubular systems. For these drawbacks, industries centered their attention on non-invasive and non-destructive testing (NDT) methodologies, which are installed on the outer tubular surface to avoid flow disturbance and desist shutting down systems for installations. Although these sensors showed excellent achievement for monitoring and inspecting pipe health conditions, the performance was not convincing for monitoring the properties of fluids. This review paper presents an overview of the real-time monitoring of fluid properties in tubular systems for industrial applications, particularly for pipe monitoring sensors, viscosity, and flow measurements. Additionally, the different available sensing mechanisms and their advantages, drawbacks, and potentials are discussed.
Gear Shape Parameter Measurement Using a Model-Based Scanning Multi-Distance Measurement Approach
Authors: Pillarz Marc , von Freyberg Axel , Fischer Andreas
Published: July 2020

To reduce wind turbine failures by defective drive trains, deviations in the geometry of large gears (diameter ≳ 1 m) must be extensively determined with single-digit micrometer uncertainties. Fixed measuring volumes limit standard measuring methods like coordinate and gear measuring instruments for large gear measurements. Therefore, a model-based scanning multi-distance measurement approach for gear shape parameters is presented. The measurement approach has a scalable design and consists of a confocal-chromatic sensor, rotary table as a scanning unit and model-based signal processing. A preliminary study on a midsize spur gear demonstrates the general feasibility of the model-based scanning multi-distance measurement approach. As a result, the mean base circle radius as the fundamental gear shape parameter is determined with an uncertainty of <5 μm. The calibration and adjustment of the sensor arrangement were performed with a known calibration gear. Scalability is not experimentally validated in this article. However, simulations verify the scalability of the measurement approach in a first step. For gears with 1 m in diameter and varying tooth flank geometries, the estimated achievable uncertainty of the mean base circle radius is still <5 μm. Therefore, the model-based scanning multi-distance measurement approach is a promising alternative for gear inspection.
An Acceptance Test for Assistive Robots
Authors: Martín Rico Francisco , Rodríguez-Lera Francisco J. , Ginés Clavero Jonatan , Guerrero-Higueras Ángel Manuel , Matellán Olivera Vicente
Published: July 2020

Socially assistive robots have been used in the care of elderly or dependent people, particularly with patients suffering from neurological diseases, like autism and dementia. There are some proposals, but there are no standardized mechanisms for assessing a particular robot’s suitability for specific therapy. This paper reports the evaluation of an acceptance test for assistive robots applied to people with dementia. The proposed test focuses on evaluating the suitability of a robot during therapy sessions. The test measures the rejection of the robot by the patient based on observational data. This test would recommend what kind of robot and what functionalities can be used in therapy. The novelty of this approach is the formalization of a specific validation process that only considers the reaction of the person to whom the robot is applied, and may be used more effectively than existing tests, which may not be adequate for evaluating assistance robots. The test’s feasibility was tested by applying it to a set of dementia patients in a specialized care facility.
Estimation and Prediction of Vertical Deformations of Random Surfaces, Applying the Total Least Squares Collocation Method
Authors: Wiśniewski Zbigniew , Kamiński Waldemar
Published: July 2020

This paper proposes a method for determining the vertical deformations treated as random fields. It is assumed that the monitored surfaces are subject not only to deterministic deformations, but also to random fluctuations. Furthermore, the existence of random noise coming from surface’s vibrations is also assumed. Such noise disturbs the deformation’s functional models. Surface monitoring with the use of the geodetic levelling network of a free control network class is carried out. Assuming that, in some cases, the control networks are insufficient in surface’s deformation analysis, additional and non–measurable reference points have been provided. The prediction of these points’ displacements and estimation of the free control network points’ displacement are carried out using the collocation method applying the total least squares adjustment. The proposed theoretical solutions were verified by the simulation methods and on the example of a real control network.
Compact Imaging Systems Based on Annular Harmonic Lenses
Authors: Skidanov Roman , Strelkov Yury , Volotovsky Sergey , Blank Veronika , Ganchevskaya Sofiya , Podlipnov Vladimir , Ivliev Nikolay , Kazanskiy Nikolay
Published: July 2020

In this study, a configuration of a compact imaging objective based on a reflecting annular harmonic lens was proposed. Light propagation through the proposed optical system was comprehensively modeled using a dedicated special program and the ZEMAX software, with the latter used to derive the point spread function (PSF). Several relationships were used to describe the connection between key parameters of the objective, including its focal length, field of view, and thickness. We demonstrated that it was possible to design a compact imaging objective whose overall length could be one to two orders of magnitude smaller than its focal length. Using direct laser writing, a reflecting annular harmonic lens was fabricated and used in the proposed objective scheme. The performance of the objective was experimentally studied by imaging a light source and a test pattern. The performance of the compact imaging objective based on a reflecting annular harmonic lens was verified in principle. A PSF value of approximately 16 microns was experimentally obtained, for a lens with a diameter of 25 mm with a focal length of 100 mm.
Interleaved Array Transducer with Polarization Inversion Technique to Implement Ultrasound Tissue Harmonic Imaging
Authors: Park Chan Yuk , Sung Jin Ho , Jeong Eun Young , Lee Hee Su , Jeong Jong Seob
Published: July 2020

In ultrasound tissue harmonic imaging (THI), it is preferred that the bandwidth of the array transducer covers at least the fundamental frequency f0 for transmission and the second harmonic frequency 2f0 for reception. However, it is challenging to develop an array transducer with a broad bandwidth due to the single resonance characteristics of piezoelectric materials. In this study, we present an improved interleaved array transducer suitable for THI and a dedicated transducer fabrication scheme. The proposed array transducer has a novel structure in which conventional elements exhibiting f0 resonant frequency and polarization-inverted elements exhibiting 2f0 resonant frequency are alternately located, and the thicknesses of all piezoelectric elements are identical. The performance of the proposed method was demonstrated by finite element analysis (FEA) simulations and experiments using a fabricated prototype array transducer. Using the proposed technique, f0 and 2f0 frequency ultrasounds can be efficiently transmitted and received, respectively, resulting in a 90% broad bandwidth feature of the transducer. Thus, the proposed technique can be one of the potential ways to implement high resolution THI.
A Novel Mine Cage Safety Monitoring Algorithm Utilizing Visible Light
Authors: Yang Xu , Pang Mingzhi , Li Peihao , Chen Pengpeng , Niu Qiang
Published: July 2020

The mine cage has an important role in the production of coal mines. It has many safety problems in the transportation of people, such as overloading of personnel and illegal outreach of human limbs. However, the harsh mine environment makes it very difficult to monitor personnel overload and limb extension. To solve these two problems, we propose a novel safety monitoring algorithm of the mine cage based on visible light. With visible light technology, our algorithm cleverly utilizes the existing underground lighting equipment (i.e., miner’s headlamp and the miner’s lamp deployed on the mine cage) as the transmitter to broadcast the light beacons representing unique identity information through visible light frequency modulation. Next, cheap photodiodes deployed in the mine cage are used as the receiver to perceive the modulated optical signals. Then we use the frequency matching method for personnel counting and the frequency power comparison method for illegal limb extension monitoring. Moreover, a novel method of monitoring the delineated safe area of the mine cage is also proposed to ensure that all the miners are in the delineated safe area. Finally, we conducted extensive experiments with a simulated mine cage model. Results show that our algorithm has superior performance. With the photodiode SD5421-002, the accuracy of personnel overload judgment and safe area monitoring of our algorithm can reach 99%, and the accuracy of limb extension monitoring is more than 96%.
Social Work with Families in Special Distress: Collaborative Practices
Authors: Casado Tatiana , Riera Joan Albert , Cardona Josefa
Published: July 2020

Collaborative practices have emerged as an effective approach for conducting social work interventions with families in special distress. This study aimed to ascertain the perspective of the social workers located in basic community social services, in relation to the development of a collaborative approach with families in special distress. The main objective was to find out the level of importance and the level of implementation that participants (N = 121) gave to the different intervention criteria included in an Inventory of Collaborative Practices. The results indicate that criteria related to basic issues in social case work (active listening, respect, and empathy) as well as the management and bureaucracy of the specific case are the most valued and performed by social workers. The least valued and performed criteria have to do with issues that involve reflective processes in the helping relationship, both with the family and with the rest of the professionals. Implications for practice and quality enhancement are discussed, as they are key aspects in the development of collaborative interventions in social work.
Global Challenges of Being a Strength Athlete during a Pandemic: Impacts and Sports-Specific Training Considerations and Recommendations
Authors: Latella Christopher , Haff G. Gregory
Published: July 2020

The ongoing global pandemic brought about by Coronavirus II (SARS-Cov-2 or COVID-19) has caused an ongoing cessation of sporting competitions and training facility closures. This is a fundamental challenge for amateur and elite sporting professionals. Although recommendations have been provided for team-sport athletes to maintain general and sport-specific conditioning, these methods are often not optimal for strength athletes (i.e., powerlifting (PL) and weightlifting (WL)) due to the unique and narrow set of performance requirements posed by these sports. The purpose of this review is to provide evidence-based information and recommendations and highlight potential strategies and approaches that may be used by strength (PL and WL) athletes during the current global crisis. Collectively, we provide evidence from resistance training literature regarding the loss of muscle strength, power and mass, minimum training frequencies required to attenuate such losses and training re-adaptation. Additionally, we suggest that time off training and competition caused by ongoing restrictions may be used for other purposes, such as overcoming injury and improving movement quality and/or mobility, goal setting, psychological development and emphasizing strength sports for health. These suggestions are intended to be useful for coaches, strength athletes and organizations where existing training strategies and recommendations are not suitable or no longer feasible.
Sustainable Curriculum Planning for Artificial Intelligence Education: A Self-Determination Theory Perspective
Authors: Chiu Thomas K.F. , Chai Ching-sing
Published: July 2020

The teaching of artificial intelligence (AI) topics in school curricula is an important global strategic initiative in educating the next generation. As AI technologies are new to K-12 schools, there is a lack of studies that inform schools’ teachers about AI curriculum design. How to prepare and engage teachers, and which approaches are suitable for planning the curriculum for sustainable development, are unclear. Therefore, this case study aimed to explore the views of teachers with and without AI teaching experience on key considerations for the preparation, implementation and continuous refinement of a formal AI curriculum for K-12 schools. It drew on the self-determination theory (SDT) and four basic curriculum planning approaches—content, product, process and praxis—as theoretical frameworks to explain the research problems and findings. We conducted semi-structured interviews with 24 teachers—twelve with and twelve without experience in teaching AI—and used thematic analysis to analyze the interview data. Our findings revealed that genuine curriculum creation should encompass all four forms of curriculum design approach that are coordinated by teachers’ self-determination to be orchestrators of student learning experiences. This study also proposed a curriculum development cycle for teachers and curriculum officers.
Revisiting Membrane Microdomains and Phase Separation: A Viral Perspective
Authors: Sengupta Prabuddha , Lippincott-Schwartz Jennifer
Published: July 2020

Retroviruses selectively incorporate a specific subset of host cell proteins and lipids into their outer membrane when they bud out from the host plasma membrane. This specialized viral membrane composition is critical for both viral survivability and infectivity. Here, we review recent findings from live cell imaging of single virus assembly demonstrating that proteins and lipids sort into the HIV retroviral membrane by a mechanism of lipid-based phase partitioning. The findings showed that multimerizing HIV Gag at the assembly site creates a liquid-ordered lipid phase enriched in cholesterol and sphingolipids. Proteins with affinity for this specialized lipid environment partition into it, resulting in the selective incorporation of proteins into the nascent viral membrane. Building on this and other work in the field, we propose a model describing how HIV Gag induces phase separation of the viral assembly site through a mechanism involving transbilayer coupling of lipid acyl chains and membrane curvature changes. Similar phase-partitioning pathways in response to multimerizing structural proteins likely help sort proteins into the membranes of other budding structures within cells.
Progress in the Development of Subunit Vaccines against Malaria
Authors: Skwarczynski Mariusz , Chandrudu Saranya , Rigau-Planella Berta , Islam Md. Tanjir , Cheong Yee S. , Liu Genan , Wang Xiumin , Toth Istvan , Hussein Waleed M.
Published: July 2020

Malaria is a life-threatening disease and one of the main causes of morbidity and mortality in the human population. The disease also results in a major socio-economic burden. The rapid spread of malaria epidemics in developing countries is exacerbated by the rise in drug-resistant parasites and insecticide-resistant mosquitoes. At present, malaria research is focused mainly on the development of drugs with increased therapeutic effects against Plasmodium parasites. However, a vaccine against the disease is preferable over treatment to achieve long-term control. Trials to develop a safe and effective immunization protocol for the control of malaria have been occurring for decades, and continue on today; still, no effective vaccines are available on the market. Recently, peptide-based vaccines have become an attractive alternative approach. These vaccines utilize short protein fragments to induce immune responses against malaria parasites. Peptide-based vaccines are safer than traditional vaccines, relatively inexpensive to produce, and can be composed of multiple T- and B-cell epitopes integrated into one antigenic formulation. Various combinations, based on antigen choice, peptide epitope modification and delivery mechanism, have resulted in numerous potential malaria vaccines candidates; these are presently being studied in both preclinical and clinical trials. This review describes the current landscape of peptide-based vaccines, and addresses obstacles and opportunities in the production of malaria vaccines.
Potential and Limitations of Cross-Protective Vaccine against Malaria by Blood-Stage Naturally Attenuated Parasite
Authors: Imai Takashi , Suzue Kazutomo , Ngo-Thanh Ha , Shimokawa Chikako , Hisaeda Hajime
Published: July 2020

Human malaria vaccine trials have revealed vaccine efficacy but improvement is still needed. In this study, we aimed to re-evaluate vaccination with blood-stage naturally attenuated parasites, as a whole-organism vaccine model against cross-strain and cross-species malaria, to establish a better vaccination strategy. C57BL/6 mice controlled blood-stage Plasmodium yoelii 17XNL (PyNL) within 1 month of infection, while mice with a variety of immunodeficiencies demonstrated different susceptibilities to PyNL, including succumbing to hyperparasitemia. However, after recovery, survivors had complete protection against a challenge with the lethal strain PyL. Unlike cross-strain protection, PyNL-recovered mice failed to induce sterile immunity against Plasmodium berghei ANKA, although prolonged survival was observed in some vaccinated mice. Splenomegaly is a typical characteristic of malaria; the splenic structure became reorganized to prioritize extra-medullary hematopoiesis and to eliminate parasites. We also found that the peritoneal lymph node was enlarged, containing activated/memory phenotype cells that did not confer protection against PyL challenge. Hemozoins remained in the spleen several months after PyNL infection. Generation of an attenuated human blood-stage parasite expressing proteins from multiple species of malaria would greatly improve anti-malaria vaccination.
Regulatory B Cells and Their Cytokine Profile in HCV-Related Hepatocellular Carcinoma: Association with Regulatory T Cells and Disease Progression
Authors: Hetta Helal F. , Mekky Mohamed A. , Zahran Asmaa M. , Abdel-Malek Mohamed O. , Ramadan Haidi K. , Shafik Engy A. , Abbas Wael A. , Abbas El-Masry Muhammad , Mohamed Nahed A. , Kamel Amira A. , Marraiki Najat , Beshbishy Amany Magdy , Batiha Gaber El-Saber , Osman Heba A. , Koneru Gopala , El-Mokhtar Mohamed A.
Published: July 2020

Although regulatory B cells (Bregs) have been proven to play a suppressive role in autoimmune diseases, infections and different tumors, little is known regarding hepatocellular carcinoma (HCC), especially in hepatitis C-related settings. Herein, we analyzed the frequency of circulating Bregs, serum levels of IL-10, IL-35 and B-cell activating factor (BAFF) and investigated their association with regulatory T cells (Tregs) and disease progression in HCV-related HCC. For comparative purposes, four groups were enrolled; chronic HCV (CHC group, n = 35), HCV-related liver cirrhosis (HCV-LC group, n = 35), HCV-related HCC (HCV-HCC group, n = 60) and an apparently healthy control (Control-group, n = 20). HCC diagnosis and staging were in concordance with the Barcelona Clinic Liver Cancer (BCLC) staging system. Analysis of the percentage of Breg cells and peripheral lymphocyte subsets (Treg) was performed by flow cytometry. Serum cytokine levels of IL-10, IL-35 and B-cell activating factor (BAFF) were measured by ELISA. The frequency of Bregs was significantly higher in the HCV-HCC group compared to the other groups and controls. A significant increase was noted in late-HCC versus those in the early stages. The frequency of Bregs was positively correlated with Tregs, serum IL-10, IL-35 and BAFF. In conclusion, Peripheral Bregs were positively correlated with the frequency of Tregs, IL-10, IL-35 and BAFF, and may be associated with HCV-related HCC progression.
Impact of Helminth Infections during Pregnancy on Vaccine Immunogenicity in Gabonese Infants
Authors: Flügge Judith , Adegnika Ayôla Akim , Honkpehedji Yabo Josiane , Sandri Thaisa L. , Askani Esther , Manouana Gédéon Prince , Massinga Loembe Marguerite , Brückner Sina , Duali Mohamed , Strunk Johannes , Mordmüller Benjamin , Agnandji Selidji Todagbe , Lell Bertrand , Kremsner Peter G. , Esen Meral
Published: July 2020

Helminth infections are common in sub-Saharan Africa. Besides direct clinical effects, a bias towards a T helper type 2 (Th2) cell immune response is observed. The consequences of parasite infection during pregnancy for the mother and particularly for the fetus and the newborn can be severe and may include impaired immune response during acute infection and vaccination. Here, we present data of immune responses to vaccines given within the expanded program on immunization (EPI) of infants born to helminth infected or non-infected mothers. The study was conducted in Lambaréné and surroundings, Gabon. Maternal helminth infection was diagnosed microscopically using the Kato-Katz method for soil-transmitted helminths (STH), urine filtration for Schistosoma haematobium infections and the saponin-based method for filarial infections. Plasma antibody levels to different vaccine antigens were measured in mothers and their offspring by enzyme-linked immunosorbent assay (ELISA) at different timepoints. We found 42.3% of the mothers to be infected with at least one helminth species. Significantly lower anti-tetanus toxoid immunoglobulin (Ig) G was detected in the cord blood of infants born to helminth infected mothers. Following vaccination, immune responses of the infants to EPI vaccines were similar between the two groups at nine and 12 months. Even though infection with helminths is still common in pregnant women in Gabon, in our setting, there was no evidence seen for a substantial effect on infants’ immune responses to vaccines given as part of the EPI.
Arthus Reaction as an Adverse Event Following Tdap Vaccination
Authors: Pool Vitali , Mege Larissa , Abou-Ali Adel
Published: July 2020

Repeat administration of tetanus toxoid-containing vaccines has rarely been associated with Arthus phenomenon, an immune-complex reaction. In the US, since 2013, tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis vaccines (Tdap) have been recommended for administration during each pregnancy. Separately, in 2019, one Tdap was approved for repeat administration in adults in the US. We aimed to describe trends in spontaneously reported Arthus reactions following Tdap in the US and to assess the risk of this phenomenon in persons receiving Tdap repeatedly. We reviewed Arthus reports in the Vaccine Adverse Events Reporting System (VAERS), 1990–2018. Reporting rates were estimated using Tdap doses distributed data. A systematic literature review was conducted in MEDLINE for any Arthus cases reported in Tdap clinical trials and observational studies published between 2000 and 2019. We found 192 Arthus reports in VAERS after any vaccine, of which 36 occurred after Tdap and none were reported during pregnancy. The Arthus reporting rate was estimated at 0.1 per million doses distributed. We identified eight published studies of Tdap administration within five years after a previous dose of tetanus toxoid-containing vaccine; no Arthus cases were reported. We conclude that Arthus reaction following Tdap is extremely rare. Increasing frequency of repeat Tdap administration in adults in the US did not result in a detectable increase in reporting rates of this phenomenon, confirming the favorable safety profile of Tdap.
Effects of Sedation by Intramuscular Administration of Medetomidine on Canine Abdominal Vascular System and Hepatic Parenchyma Imaging Using Enhancement Dynamic Computed Tomography
Authors: Kutara Kenji , Kanda Teppei , Maeta Noritaka , Mochizuki Yohei , Itoh Yoshiki , Ono Fumiko , Asanuma Taketoshi
Published: July 2020

This prospective crossover study compared the effects of intramuscular administration of medetomidine for sedation on parameters of the abdominal vascular system, measured by enhancement computed tomography (CT), to those of propofol-induced sevoflurane maintenance anesthesia, as a control, in five clinically healthy adult male beagle dogs (11.4–12.8 kg). Each animal underwent both protocols at a 1-week interval. The enhancement (HU) and time to peak enhancement on CT were measured for the aorta (AO), caudal vena cava (CVC), portal vein (PV), and hepatic parenchyma (HP). The contrast effects in the AO, PV, and HP were significantly delayed under medetomidine sedation compared to the control anesthesia protocol. Particularly, the contrast effect in the PV and HP was significantly delayed under sedation, appearing approximately 1 min after contrast medium injection. This delay likely reflects the peripheral vasoconstrictive effect of medetomidine. We noted a generally early high contrast enhancement of the CVC under medetomidine sedation, likely contributed by the induced bradycardia. Therefore, findings obtained on contrast enhancement CT under medetomidine sedation may be different from those obtained under propofol-induced sevoflurane maintenance anesthesia. These differences are important to consider when using the findings to inform diagnosis.
Bifurkasi Hopf pada Model Lotka-Volterra Orde-Fraksional dengan Efek Allee Aditif pada Predator
Authors: Panigoro Hasan S. , Savitri Dian
Published: July 2020

This article aims to study the dynamics of a Lotka-Volterra predator-prey model with Allee effect in predator. According to the biological condition, the Caputo fractional-order derivative is chosen as its operator. The analysis is started by identifying the existence, uniqueness, and non-negativity of the solution. Furthermore, the existence of equilibrium points and their stability is investigated. It has shown that the model has two equilibrium points namely both populations extinction point which is always a saddle point, and a conditionally stable co-existence point, both locally and globally. One of the interesting phenomena is the occurrence of Hopf bifurcation driven by the order of derivative. Finally, the numerical simulations are given to validate previous theoretical results.
Corporate Social Responsibility Terhadap Nilai Perusahaan Dengan Struktur Modal oSebagai Moderasi (Studi Kasus pada Perusahaan Yang Terdaftar di Indeks SRI KEHATI Periode 2017-2018)
Authors: Sunandes Aris
Published: July 2020

The opurpose oof othis ostudy owas oto oexamine: othe oeffect oof ocorporate osocial oresponsibility oon ofirm ovalue, othe oeffect oof ocapital ostructure oon ofirm ovalue oand oto otest othe oability oof ocapital ostructure oto omoderate ocorporate osocial oresponsibility oon ofirm ovalue oin ocompanies olisted oon othe oSri-Kehati oIndex. oThe oresearch omethod ouses othe oModerated oRegression oAnalysis omodel, opurposive osampling owith o25 ocompanies otwo oyears oof oobservation onamely o2017-2018. oThe oresults oof othis ostudy oare othe ocapital ostructure odoes onot oaffect othe ovalue oof othe ocompany, ocorporate osocial oresponsibility odoes onot oaffect othe ovalue oof othe ocompany, othe opotential ocapital ostructure oin omoderating othe orelationship oof ocorporate osocial oresponsibility oto othe ovalue oof othe ocompany oin ocompanies olisted oon othe oSri-Kehati oIndex.
A note on differential-algebraic systems with impulsive and hysteresis phenomena
Authors: Petrenko Pavel , Samsonyuk Olga , Staritsyn Maxim
Published: July 2020

n this note, we single out some promising classes of differential-algebraic equations (DAEs) with hysteresis phenomena, and propose their meaningful generalizations. We consider D Es of index 2 having two features: i) non-linearity of hysteresis type modeled by a sweeping process, and ii) impulsive control represented by a bounded signed Borel measure. For such a DAE we design an equivalent structural form, based on the Kronecker-Weierstrass transformation, and prove a necessary and sufficient condition for the existence and uniqueness of a solution to an initial value problem. We propose a notion of generalized solution to a DAE as a realization of impulsive trajectory relaxation. This relaxation is described by a dynamical system with states of bounded variation and can be equivalently represented as a system of “ordinary” DAEs.
Hamiltonian path problem solution using DNA computing
Authors: Sergeenko Anna , Yakunina Maria , Granichin Oleg
Published: July 2020

In this article we study DNA computing, a method which is based on working with DNA molecules in a laboratory. That approach is implemented in solving one of the most popular combinatorial problem — the Hamiltonian path problem. Related to recent improvements in the biophysics methods, which are needed for DNA computing, we propose to change some steps in the classical algorithm to increase accuracy of this method. The branch-and-bound method, the most popular method which is realized on a computer, is also shown in this paper to compare its performance with the time consumption of DNA computing. The results of that comparison prove that it becomes inefficient to use the branch-and-bound method from the counted number of vertices because of its exponentially growing complexity, while DNA computing works parallel and has linearly growing time consumption.
RENCANA PERBAIKAN PEMBELAJARAN MATA PELAJARAN MATEMATIKA DI SD/MI
Authors: Nurhasanah Nurhasanah
Published: July 2020

Metode drill adalah metode dalam pengajaran dengan melatih peserta didik terhadap bahan yang sudah diajarkan dan diberikan agar memiliki ketangkasan atau keterampilan dari apa yang telah dipelajari. Metode ini bertujuan agar daya pikir anak makin lama semakin bertambah baik, lebih teratur dan teliti dalam mendorong ingatannya. Selain itu pengetahuan anak akan bertambah, karena memperoleh pemahaman yang lebih baik dan mendalam.
Pemahaman Orang Tua Mengenai Urgensi Bermain Dalam Meningkatkan Perkembangan Sosial Anak Usia Dini
Authors: Rahmadianti Novia
Published: July 2020

Artikel ini merupakan kajian literatur yang terkait dengan pemahaman orang tua mengenai urgensi bermain yang dapat meningkatkan aspek perkembangan sosial pada anak usia dini. Lingkungan sekitar anak khususnya orang tua memiliki peran yang sangat penting bagi perkembangan anak, orang tua yang paham mengenai pentingnya bermain bagi anak akan dapat membantu perkembangan anak berkembang dengan baik. Bermain merupakan kebutuhan bagi anak karena anak belajar sambil bermain, salah satu aspek perkembangan yang dapat berkembang melalui bermain yaitu aspek perkembangan sosial. Bermain dapat melatih keterampilan sosial pada anak seperti kerjasama, berbagi dengan sesama, menghargai sesama, tolong menolong, menumbuhkan rasa empati, menjadi pemimpin yang baik, tanggung jawab dan jujur. Banyak manfaat yang didapat oleh anak ketika bermain selain melatih keterampilan sosial, anak juga akan mendapat pengetahuan dan pengalaman baru melalui bermain. Maka dari itu orang tua sebagai lingkungan pertama anak perlu memahami pentingnya bermain bagi anak usia dini, agar orang tua dapat membantu perkembangan anak berkembang secara optimal.
PERAN GURU DALAM MENGOPTIMALKAN TUGAS-TUGAS PERKEMBANGAN PADA ANAK USIA DINI
Authors: Husain Aghnaita , Irmawati Irmawati , Paus Maimun
Published: July 2020

Penelitian ini bertolak dari konsep tentang usia kelahiran hingga memasuki pendidikan dasar sebagai masa keemasan, sekaligus masa kritis dalam tahapan kehidupan yang akan menentukan perkembangan selanjutnya. Oleh sebab itu, sangatlah penting adanya upaya untuk mengembangkan seluruh potensi anak yang harus dimulai sejak dini secara optimal. Selain itu, perkembangan anak yang akan berhadapan dengan fenomena budaya yang berbeda-beda, akan memunculkan sejumlah tugas perkembangan yang harus diselesaikan sesuai dengan periode usianya masing-masing. Sejalan dengan hal ini maka diperlukan adanya bantuan dari lingkungan sekitar, salah satunya yakni peran guru di sekolah. Metode penelitian menggunakan penelitian kepustakaan dengan mendeskripsikan tentang peran guru sebagai upaya dalam mengembangkan tugas-tugas perkembangan pada anak usia dini. Adapun teknik pengumpulan data yang digunakan yaitu dokumentasi dengan menggunakan analisis isi. Berdasarkan hasil penelitian, maka dapat diperoleh bahwa tugas perkembangan merupakan tugas yang muncul pada periode tertentu dalam rentang kehidupan individu. Guru sebagai bagian dari sekolah yang merupakan lembaga pendidikan formal dimana secara sistematik dalam melaksanakan program, turut berperan dalam mengembangkan tugas perkembangan anak. Di antaranya melalui kelompok teman sebaya, perkembangan kemandirian pribadi, keimanan dan ketakwaan kepada Tuhan Yang Maha Esa, serta melaksanakan pembelajaran berbasis perkembangan.
GEOGRAPHY OF BATS IN KHANTY-MANSIYSK AUTONOMOUS OKRUG - YUGRA
Authors: Bernikov K.A. , Starikov V.P. , Nakonechnyi N.V.
Published: July 2020

Targeted studies of bats in Khanty-Mansiysk Autonomous Okrug-Yugra revealed six species of bats. Animals of this group are spread throughout the region not-evenly, the populations are rarer. Low reproductive capacity and the number associated with living on the border of habitats in Yugra contributed to the inclusion of all species of bats in the regional Red Book. In this article, along with known data, the authors present modern information on the distribution of bats in the territory of the Khanty-Mansiysk Autonomous Okrug. Possible causes of local distribution of species are discussed. The largest species diversity is characteristic of the southern and southwestern part of the region, which is due to the proximity of possible winter sites in the caves of the Northern Ural. In the central and northern part of Yugra there are only ecologically flexible species - the Northern bat and Parti-colored bat.
ACOUSTIC CHARACTERISTICS OF ABAKAN
Authors: Lisovenko А.V. , Zakharova O.L. , Yamskikh G.Yu.
Published: July 2020

This article assesses the acoustic pollution of Abakan, which belongs to the category of large cities. Significant excess, according to the results of research, reaching 110 dB(A), occurs pointwise along highways and is observed in the central part of the city where the railway tracks run. Excesses on these sites are recorded twice as high as the normative indicator which is equal 55 dB(A). Building sites located in the northern, western and southwestern city districts should be considered as problematic areas in terms of extra acoustic load. Within these areas, the noise load reaches 65 dB(A). In northern and southern residential areas of Abakan, the noise level corresponds to the acoustic comfort mode. Additional noise measurements made in mid- and multi-storey residential areas of the city showed that the highest noise level is observed in winter period and reaches 68,8 dB(A). In summer, the noise level does not exceed the standard adopted for this physical factor.