bluuebunny/crossref_metadata_2025 huggingface dataset:
The Arabic Version of the Impact of Event Scale-Revised: Psychometric Evaluation among Psychiatric Patients and the General Public within the Context of COVID-19 Outbreak and Quarantine as Collective Traumatic Events
Authors: Ali Amira Mohammed , Al-Amer Rasmieh , Kunugi Hiroshi , Stănculescu Elena , Taha Samah M. , Saleh Mohammad Yousef , Alkhamees Abdulmajeed A. , Hendawy Amin Omar
Published: April 2022

The Coronavirus Disease-19 (COVID-19) pandemic has provoked the development of negative emotions in almost all societies since it first broke out in late 2019. The Impact of Event Scale-Revised (IES-R) is widely used to capture emotions, thoughts, and behaviors evoked by traumatic events, including COVID-19 as a collective and persistent traumatic event. However, there is less agreement on the structure of the IES-R, signifying a need for further investigation. This study aimed to evaluate the psychometric properties of the Arabic version of the IES-R among individuals in Saudi quarantine settings, psychiatric patients, and the general public during the COVID-19 outbreak. Exploratory factor analysis revealed that the items of the IES-R present five factors with eigenvalues > 1. Examination of several competing models through confirmatory factor analysis resulted in a best fit for a six-factor structure, which comprises avoidance, intrusion, numbing, hyperarousal, sleep problems, and irritability/dysphoria. Multigroup analysis supported the configural, metric, and scalar invariance of this model across groups of gender, age, and marital status. The IES-R significantly correlated with the Depression Anxiety Stress Scale-8, perceived health status, and perceived vulnerability to COVID-19, denoting good criterion validity. HTMT ratios of all the subscales were below 0.85, denoting good discriminant validity. The values of coefficient alpha in the three samples ranged between 0.90 and 0.93. In path analysis, correlated intrusion and hyperarousal had direct positive effects on avoidance, numbing, sleep, and irritability. Numbing and irritability mediated the indirect effects of intrusion and hyperarousal on sleep and avoidance. This result signifies that cognitive activation is the main factor driving the dynamics underlying the behavioral, emotional, and sleep symptoms of collective COVID-19 trauma. The findings support the robust validity of the Arabic IES-R, indicating it as a sound measure that can be applied to a wide range of traumatic experiences.
Nitriding of 316L Steel in a Glow Discharge Plasma
Authors: Frączek Tadeusz , Prusak Rafał , Ogórek Marzena , Skuza Zbigniew
Published: April 2022

The article presents the results of the research on the nitriding process of 316L austenitic steel and the change in surface properties resulting from this process used in medicine, orthopedics, and in fuel cells. The processes were carried out with the following parameters: time from 5 to 17 h, temperature from 430 °C to 490 °C. The study presents the results of tests of the 316L austenitic steel substrate layer subjected to plasma nitriding of a direct current glow discharge, i.e., in the area isolated from both the cathode and the anode. Additionally, the influence of the active screen on the nitriding process in this area of the direct current discharge was studied. The following tests were carried out: nitrogen diffusion depth test, hardness test, wear resistance test, microstructure analysis, corrosion resistance, and distribution of the element concentration in the surface layer. The research allowed for the conclusion that each variant of nitriding contributed to a change in the examined properties, while the observed scale and nature of the changes were different.
Effect of Cold-Rolling Directions on Recrystallization Texture Evolution of Pure Iron
Authors: Ogawa Toshio , Suzuki Yutaro , Adachi Yoshitaka , Yamaguchi Atsushi , Matsubara Yukihiro
Published: April 2022

The influence of cold-rolling directions on the recrystallization texture evolution of pure iron was examined. As-received pure iron sheets were cold-rolled under two different conditions (specimens A and B). Specimen A was cold-rolled in the vertical direction against the cold-rolling direction of the as-received sheet. Specimen B was cold-rolled in the vertical direction against the cold-rolling direction of the as-received sheet, and then in the cold-rolling direction of the as-received sheet. Cold-rolled specimens were heated to each desired temperature before being quenched in water to room temperature (298 ± 2 K). Both cold-rolled specimens showed the development of γ-fiber and {100}<011> orientation. Additionally, γ-fiber formed comparatively more in cold-rolled specimen A, while α-fiber developed comparatively more in cold-rolled specimen B. Strain distribution in cold-rolled specimen A was presumably inhomogeneous, whereas that in cold-rolled specimen B was rather uniform at the macro-scale. The formation of γ-fiber was confirmed in annealed specimen A. In annealed specimen B, however, the recrystallization texture tended to be random, and the formation of α-fiber was observed. Furthermore, the formation of Goss orientation in both annealed specimens was established. Recrystallized ferrite grains with Goss orientation nucleated in high strain regions of cold-rolled specimen. These findings show that by devising the cold-rolling direction, it is possible to discover new types of recrystallization textures.
Emerging Trends in Genetic Engineering of Microalgae for Commercial Applications
Authors: Grama Samir B. , Liu Zhiyuan , Li Jian
Published: April 2022

Recently, microalgal biotechnology has received increasing interests in producing valuable, sustainable and environmentally friendly bioproducts. The development of economically viable production processes entails resolving certain limitations of microalgal biotechnology, and fast evolving genetic engineering technologies have emerged as new tools to overcome these limitations. This review provides a synopsis of recent progress, current trends and emerging approaches of genetic engineering of microalgae for commercial applications, including production of pharmaceutical protein, lipid, carotenoids and biohydrogen, etc. Photochemistry improvement in microalgae and CO2 sequestration by microalgae via genetic engineering were also discussed since these subjects are closely entangled with commercial production of the above mentioned products. Although genetic engineering of microalgae is proved to be very effective in boosting performance of production in laboratory conditions, only limited success was achieved to be applicable to industry so far. With genetic engineering technologies advancing rapidly and intensive investigations going on, more bioproducts are expected to be produced by genetically modified microalgae and even much more to be prospected.
Theragra chalcogramma Hydrolysates, Rich in Gly-Leu-Pro-Ser-Tyr-Thr, Exerts Anti-Photoaging Potential via Targeting MAPK and NF-κB Pathways in SD Rats
Authors: Xu Defeng , Zhao Mouming , Lin Haisheng , Li Caihong
Published: April 2022

Previous studies have revealed that excessive exposure to UV irradiation is the main cause of skin photoaging and the signaling pathways of MAPK and NF-κB are involved in this progression. The present study aims to investigate the anti-photoaging effects of low molecular weight hydrolysates from Theragra chalcogramma (TCH) and to clarify the underlying mechanism. The degradation of mechanical barrier functions in photoaged skin was substantially ameliorated after TCH administration; meanwhile, TCH significantly elevated the antioxidant capacity and suppressed the over-production of inflammatory cytokine IL-1β. Moreover, the histopathological deteriorations such as epidermal hyperplasia and dermal loss were significantly alleviated, along with the increase in procollagen type I content and decrease in MMP-1 activity (p < 0.05). Furthermore, TCH effectively blocked the MAPK and NF-κB signaling pathways through inhibition of the phosphorylation of p38, JNK, ERK, iκB, and p65 proteins. Collectively, these data indicate that TCH has potential as a novel ingredient for the development of anti-photoaging foods.
Impact of Activation of EGFL7 within Microenvironment of High Grade Ovarian Serous Carcinoma on Infiltration of CD4+ and CD8+ Lymphocytes
Authors: Sznurkowski Jacek J. , Żawrocki Anton , Krawczyńska Natalia , Bieńkowski Michał , Wasąg Bartosz , Biernat Wojciech
Published: April 2022

Background: It has been demonstrated that Egfl7 promotes tumor cell escape from immunity by downregulating the activation of tumor blood vessels. Aim: to analyze mRNA expression of EGFL7 within the tumor microenvironment of high-grade ovarian serous carcinoma and its association with a number of intraepithelial CD4+/CD8+ lymphocytes and ICAM-1 expression. Methods: qPCR analysis of EGFL7 mRNA in cancer cells and adjacent stromal endothelium microdissected from formalin-fixed paraffin-embedded tumors of 59 high-grade ovarian serous carcinoma patients, was performed. Infiltration of intraepithelial lymphocytes (CD4+/CD8+) and expression of ICAM-1 were evaluated by immunohistochemistry and compared between tumors with different statuses of EGFL7 expression. Results: EGFL7 was expressed in cancer cells (9/59, 15.25%), endothelium (8/59, 13.56%), or both cancer cells and adjacent endothelium (4/59, 6.78%). ICAM-1 was expressed on cancer cells (47/59, 79.66%), stromal endothelium (46/59, 77.97%), or both epithelium and endothelium (40 of 59, 67.8%). EGFL7-positivity of cancer cells and endothelium was associated with lower intraepithelial inflow of CD4+ (p = 0.022 and p = 0.029, respectively) and CD8+ lymphocytes (p = 0.004 and p = 0.031, respectively) but impact neither epithelial nor endothelial ICAM-1 expression (p = 0.098 and p = 0.119, respectively). The patients’ median follow-up was 23.83 months (range 1.07–78.07). Lack of prognostic significance of EGFL7-status and ICAM-1 expression was notified. Conclusion: EGFL7 is activated in the cancer cells as frequently as in the endothelium of human high-grade ovarian serous carcinoma. Activation of EGFL7 in cancer cells and/or endothelial cells could negatively impact diapedesis regardless of localization.
Beam Shaping in Laser Powder Bed Fusion: Péclet Number and Dynamic Simulation
Authors: Grigoriev Sergey N. , Gusarov Andrey V. , Metel Alexander S. , Tarasova Tatiana V. , Volosova Marina A. , Okunkova Anna A. , Gusev Andrey S.
Published: April 2022

A uniform distribution of power density (energy flux) in a stationary laser beam leads to a decrease in the overheating of the material in the center of the laser beam spot during laser powder bed fusion and a decrease in material losses due to its thermal ablation and chemical decomposition. The profile of the uniform cylindrical (flat-top) distribution of the laser beam power density was compared to the classical Gaussian mode (TEM00) and inverse Gaussian (donut) distribution (airy distribution of the first harmonic, TEM01* = TEM01 + TEM10). Calculation of the Péclet number, which is a similarity criterion characterizing the relationship between convective and molecular processes of heat transfer (convection to diffusion) in a material flow in the liquid phase, shows that the cylindrical (flat-top) distribution (TEM01* + TEM00 mode) is effective in a narrow temperature range. TEM00 shows the most effective result for a wide range of temperatures, and TEM01* is an intermediate in which evaporation losses decrease by more than 2.5 times, and it increases the absolute laser bandwidth when the relative bandwidth decreases by 24%.
Comparative Study of the Dissolution of LCO in HCl Medium with and without H2O2
Authors: Drajlin D. Sebastián , Suarez Daniela S. , Toro Norman , Gálvez Edelmira D. , Pinna Eliana G. , Rodriguez Mario H.
Published: April 2022

The dissolution of LiCoO2 (LCO) from spent lithium-ion batteries (LIBs) has been widely studied with organic and inorganic acids. Among these acids, HCl is the one that showed the best results when used at concentrations higher than 4 M. However, its higher cost compared with other acids is disadvantageous. Taking this into account, this work aims to perform a comparative study of the effect of different operational variables such as temperature, reaction time, leaching agent concentration (HCl) and reducing agent concentration (H2O2) on the dissolution efficiency of LCO for the systems HCl and HCl-H2O2 to determine the optimal parameters to achieve a maximum dissolution in minimum time at low temperatures and reagent concentrations. Increasing temperature, time and concentration of the reagents had a positive effect on the dissolution of LCO. When working with HCl 1.8 M, the highest dissolution for LCO, 91.0% was obtained at 348 K for 60 min. Furthermore, a slightly higher oxide dissolution (93.0%) was obtained in a reducing medium at the same temperature in half the time and with a concentration of HCl more than ten times lower. This will allow us to propose an alternative process to the existing ones with economic and ecological advantages.
The Effect of a Hydrogen Reduction Procedure on the Microbial Synthesis of a Nano-Pd Electrocatalyst for an Oxygen-Reduction Reaction
Authors: Huang Jingwen , Zhang Guoqing , Deng Xiaoting , Li Qingxin , Zhou Haikun , Xie Zhiyong , Liu Xueduan , Liu Feng , Liang Yili
Published: April 2022

Noble-metal electrocatalysts supported by biological-organism-derived carbons have attracted attention from the public due to the growing demands for green synthesis and environmental protection. Carbonization at high temperatures and hydrogen reduction are critical steps in this technical route. Herein, Shewanella oneidensis MR-1 were used as precursors, and the effects of the hydrogen-reduction procedure on catalysts were explored. The results showed that the performances of FHTG (carbonization followed by hydrogen reduction) displayed the best performance. Its ECSA (electrochemical surface area), MA (mass activity), and SA (specific activity) reached 35.01 m2 g−1, 58.39 A·g−1, and 1.66 A cm−2, respectively, which were 1.17, 1.75, and 1.50 times that of PHTG (prepared through hydrogen reduction followed by carbonization) and 1.56, 2.26, and 1.44 times that of DHTG (double hydrogen reduction). The high performance could be attributed to its fine particle size and rich N content, and the specific regulation mechanism was also proposed in this paper. This study opens a practical guide for effectively avoiding particle agglomeration during the fabrication process for catalysts.
Airborne LTA Nanozeolites Characterization during the Manufacturing Process and External Sources Interaction with the Workplace Background
Authors: Ferrante Riccardo , Boccuni Fabio , Tombolini Francesca , Natale Claudio , Lega Daniela , Antonini Alessandra , Iavicoli Sergio
Published: April 2022

Engineered nanoscale amorphous silica nanomaterials are widespread and used in many industrial sectors. Currently, some types of silicon-based nanozeolites (NZs) have been synthesized, showing potential advantages compared to the analogous micro-forms; otherwise, few studies are yet available regarding their potential toxicity. In this respect, the aim of the present work is to investigate the potential exposure to airborne Linde Type A (LTA) NZs on which toxicological effects have been already assessed. Moreover, the contributions to the background related to the main emission sources coming from the outdoor environment (i.e., vehicular traffic and anthropogenic activities) were investigated as possible confounding factors. For this purpose, an LTA NZ production line in an industrial factory has been studied, according to the Organisation for Economic Cooperation and Development (OECD) guidelines on multi-metric approach to investigate airborne nanoparticles at the workplace. The main emission sources of nanoparticulate matter within the working environment have been identified by real-time measurements (particle number concentration, size distribution, average diameter, and lung-deposited surface area). Events due to LTA NZ spillage in the air during the cleaning phases have been chemically and morphologically characterized by ICP-MS and SEM analysis, respectively.
Preparation of Novel Mesoporous LaFeO3-SBA-15-CTA Support for Syngas Formation of Dry Reforming
Authors: Li Luming , Wu Song , Li Hongmei , Deng Jie , Li Junshan
Published: April 2022

A nanocomposite NiPt/5LSBA-160 catalyst comprised of highly dispersed Ni nanoparticles contacting intimately with Pt over novel mesoporous LaFeO3-SBA-15-CTA support with a high specific surface area (SSA) was successfully developed for the dry reforming of methane. Results revealed that the high SSA mesoporous LaFeO3-SBA-15-CTA materials could first be synthesized by an in situ growth hydrothermal process and used as an excellent carrier candidate of Ni-based catalysts to achieve enhanced catalytic activity due to the strong interaction between LaFeO3 and Ni species. Moreover, the introduction of Pt over a Ni/5LSBA-160 catalyst would further promote the interaction between Ni and support, improve the dispersion of active Ni centers and obtain a higher syngas formation rate as well as tolerance to carbon coking than that of a Pt-free Ni/5LSBA-160 catalyst sample. This finding uncovers a promising prospect for high SSA mesoporous perovskite preparation and utilization in catalysis such as oxidation, hydrogenation, photocatalysis, energy conversion and so on.
Ischemic Stroke and SARS-CoV-2 Infection: The Bidirectional Pathology and Risk Morbidities
Authors: Chavda Vishal , Chaurasia Bipin , Fiorindi Alessandro , Umana Giuseppe E. , Lu Bingwei , Montemurro Nicola
Published: April 2022

Stroke is a fatal morbidity that needs emergency medical admission and immediate medical attention. COVID-19 ischemic brain damage is closely associated with common neurological symptoms, which are extremely difficult to treat medically, and risk factors. We performed literature research about COVID-19 and ischemia in PubMed, MEDLINE, and Scopus for this current narrative review. We discovered parallel manifestations of SARS-CoV-19 infection and brain ischemia risk factors. In published papers, we discovered a similar but complex pathophysiology of SARS-CoV-2 infection and stroke pathology. A patient with other systemic co-morbidities, such as diabetes, hypertension, or any respiratory disease, has a fatal combination in intensive care management when infected with SARS-CoV-19. Furthermore, due to their shared risk factors, COVID-19 and stroke are a lethal combination for medical management to treat. In this review, we discuss shared pathophysiology, adjuvant risk factors, challenges, and advancements in stroke-associated COVID-19 therapeutics.
Association between Stages of Hepatic Steatosis and Physical Activity Performance in Adults with Metabolic Syndrome: A Cross-Sectional Analysis in FLIPAN Study
Authors: Mascaró Catalina M. , Bouzas Cristina , Montemayor Sofía , Casares Miguel , Gómez Cristina , Ugarriza Lucía , Borràs Pere-Antoni , Martínez J. Alfredo , Tur Josep A.
Published: April 2022

Background: Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease. The best treatment now is a healthy lifestyle with a Mediterranean diet and physical activity (PA). Objective: To assess the association between stages of hepatic steatosis and physical activity performance in adults with metabolic syndrome. Design: Cross-sectional study in 155 participants (40–60 years old) with MetS, a diagnosis of NAFLD by magnetic resonance imaging and BMI (body mass index) between 27 and 40 kg/m2. Methods: Stages of hepatic steatosis were assessed and defined according to the percentage of intrahepatic fat contents: stage 0 ≤ 6.4% (control group); stage 1 = 6.4–17.4%; stage 2 ≥ 17.4%. Fitness was assessed through ALPHA-FIT test battery for adults, aerobic capacity by Chester-step test and PA by accelerometry and Minnesota questionnaire. Results: Participants without NAFLD reported more years of education and major socioeconomic status than participants with NAFLD. A higher percentage of people in the most advanced stage of NAFLD were no smokers and no alcohol consumers. They also had higher stages of steatosis, lower sitting handgrip, standing handgrip, Chester step test values, sleep efficiency, and energy expenditure, and higher intensity of light and moderate physical activity, and self-reported physical activity. Conclusions: NAFLD patients showed lower fitness status, aerobic capacity, sleep efficiency and energy expenditure than non-NAFLD participants.
Obeticholic Acid Reduces Kidney Matrix Metalloproteinase Activation Following Partial Hepatic Ischemia/Reperfusion Injury in Rats
Authors: Palladini Giuseppina , Cagna Marta , Di Pasqua Laura Giuseppina , Adorini Luciano , Croce Anna Cleta , Perlini Stefano , Ferrigno Andrea , Berardo Clarissa , Vairetti Mariapia
Published: April 2022

We have previously demonstrated that the farnesoid X receptor (FXR) agonist obeticholic acid (OCA) protects the liver via downregulation of hepatic matrix metalloproteinases (MMPs) after ischemia/reperfusion (I/R), which can lead to multiorgan dysfunction. The present study investigated the capacity of OCA to modulate MMPs in distant organs such as the kidney. Male Wistar rats were dosed orally with 10 mg/kg/day of OCA (5 days) and were subjected to 60-min partial hepatic ischemia. After 120-min reperfusion, kidney biopsies (cortex and medulla) and blood samples were collected. Serum creatinine, kidney MMP-2, and MMP-9-dimer, tissue inhibitors of MMPs (TIMP-1, TIMP-2), RECK, TNF-alpha, and IL-6 were monitored. MMP-9-dimer activity in the kidney cortex and medulla increased after hepatic I/R and a reduction was detected in OCA-treated I/R rats. Although not significantly, MMP-2 activity decreased in the cortex of OCA-treated I/R rats. TIMPs and RECK levels showed no significant differences among all groups considered. Serum creatinine increased after I/R and a reduction was detected in OCA-treated I/R rats. The same trend occurred for tissue TNF-alpha and IL-6. Although the underlying mechanisms need further investigation, this is the first study showing, in the kidney, beneficial effects of OCA by reducing TNF-alpha-mediated expression of MMPs after liver I/R.
Polyisocyanide Quaternary Ammonium Salts with Exceptionally Star-Shaped Structure for Enhanced Antibacterial Properties
Authors: Zhang Hongguang , Liu Lijia , Hou Peng , Pan Hong , Fu Shuang
Published: April 2022

The development of non-polluting and non-hazardous polymeric antimicrobial agents has become a hot issue in current research and development. Among them, polymer quaternary ammonium salts are thought to be one of the most promising materials for antibacterial efficacy. Here, we present an efficient strategy for synthesizing polyisocyanide quaternary ammonium salts (PQASs) with a novel star-shaped structure. Benefitting from the novel structure, increased cation density and enhanced water solubility, the prepared star polyisocyanide quaternary ammonium salts (S-PQASs) exhibit excellent antibacterial properties against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). In particular, S-POcQAS-M50 (where M stands for isonitrile monomer and 50 stands for the initial feeding ratio) showed the best antimicrobial activity with minimum inhibitory concentration (MIC) of 17 and 20 µg/mL against E. coli and S. aureus, respectively. It was also found that the unique star-shaped structure can give QASs with improved antimicrobial performance compared with our previously prepared linear quaternary ammonium salts (L-PQASs). These results demonstrated that the antibacterial activity of QASs is closely related to its structure. This work provides an idea for the design of efficient polymeric antimicrobial agents.
Investigation of Loneliness and Social Support in Patients with Eating Disorders: A Case-Control Study
Authors: Makri Eleni , Michopoulos Ioannis , Gonidakis Fragiskos
Published: April 2022

Loneliness and, to a lesser degree, social support are considered under-researched topics in the literature on eating disorders (ED). This study attempted to expand the relevant body of research by examining loneliness in combination with social support in ED patients and in healthy controls (HC). Binge-eating problems, emotional eating, resilience, anxiety, and depression symptoms were also assessed. Thirty-two patients with ED and twenty-nine HC completed the following measures: UCLA Loneliness Scale, Social Support Questionnaire—Short Form, Binge Eating Scale, Emotional Eating Scale, Connor–Davidson Resilience Scale, Hospital Anxiety and Depression Scale, and the Eating Disorder Examination Questionnaire. Eating-disorder patients showed higher levels of loneliness and lower levels of social support—both in terms of perceived availability and satisfaction—than HC. Anorexia nervosa (AN), bulimia nervosa (BN), and binge-eating disorder (BED) subgroups did not differ significantly on either of these variables. In ED patients, loneliness was only correlated with Social Support Satisfaction (negatively) and depressive symptomatology (positively). Patients with ED appear to be lonelier and less satisfied with their social support compared to HC. We found similar levels of loneliness and social support between AN, BN, and BED sufferers. Decreased social support satisfaction and elevated symptoms of depression could account for ED patients’ high levels of loneliness.
Magnetometric Surveys for the Non-Invasive Surface and Subsurface Interpretation of Volcanic Structures in Planetary Exploration, a Case Study of Several Volcanoes in the Iberian Peninsula
Authors: Díaz Michelena Marina , Kilian Rolf , Rivero Miguel Ángel , Fernández Romero Sergio , Ríos Francisco , Mesa José Luis , Oyarzún Andrés
Published: April 2022

Volcanoes are typical features of the solar system that offer a window into the interior of planets. Thus, their study can improve the understanding of the interiors and evolution of planets. On Earth, volcanoes are monitored by multiple sensors during their dormant and active phases. Presently, this is not feasible for other planets’ volcanoes. However, robotic vehicles and the recent technological demonstration of Ingenuity on Mars open up the possibility of using the powerful and non-destructive geophysical tool of magnetic surveys at different heights, for the investigation of surfaces and subsurfaces. We propose a methodology with a view to extract information from planetary volcanoes in the short and medium term, which comprises an analysis of the morphology using images, magnetic field surveys at different heights, in situ measurements of magnetic susceptibility, and simplified models for the interpretation of geological structures. This methodology is applied successfully to the study of different examples of the main volcanic zones of the Iberian Peninsula, representative of the Martian intraplate volcanism and similar to Venus domes, as a preparatory action prior to the exploration of the rocky planets’ surfaces.
Analysis of Small Sea-Surface Targets Detection Performance According to Airborne Radar Parameters in Abnormal Weather Environments
Authors: Bounaceur Hamza , Khenchaf Ali , Le Caillec Jean-Marc
Published: April 2022

Along with the rapid development of marine radar, and particularly those carried on aircraft, the detection of small-sized targets which pose an increasing threat has become one of the main areas of interest. However, by considering an observation chain from an aircraft (such as a drone) in a maritime environment, with the aim of detecting and tracking of low signal-to-clutter ratio (SCR) targets, one of the important points would be the analysis of the radar system performance according to the radar input parameters, the atmospheric propagation medium, the various sea clutter characterization, and the type of targets (RCS, speed, etc.) in this environment. Therefore, it is necessary to obtain the overall path loss including the anomalous atmospheric environment, gas attenuation, clouds attenuation, rainfall attenuation, and beam scanning loss. To consider atmospheric attenuations, ITU-R models are used. On another side, because of spikes and dynamic variation properties, sea clutter is generally described by the statistical distribution with long tail and by its wider Doppler spectrum. Conventional algorithms such as those based on statistical models, MTI, and MTD processing are often limited, especially for the target of low speed and low RCS. Therefore, sea clutter, including empirical and statistical models available, is considered to estimate and simulate the impact of radar input parameters, targets RCS, and sea state on detection performance. The Doppler frequency of target echo which can be exploited for coherent processing is described by assuming an adequate scenario of observation geometry.
Deep Federated Adaptation: An Adaptative Residential Load Forecasting Approach with Federated Learning
Authors: Shi Yuan , Xu Xianze
Published: April 2022

Residential-level short-term load forecasting (STLF) is significant for power system operation. Data-driven forecasting models, especially machine-learning-based models, are sensitive to the amount of data. However, privacy and security concerns raised by supervision departments and users limit the data for sharing. Meanwhile, the limited data from the newly built houses are not sufficient to support building a powerful model. Another problem is that the data from different houses are in a non-identical and independent distribution (non-IID), which makes the general model fail in predicting accurate load for the specific house. Even though we can build a model corresponding to each house, it costs a large computation time. We first propose a federated transfer learning approach applied in STLF, deep federated adaptation (DFA), to deal with the aforementioned problems. This approach adopts the federated learning architecture to train a global model without undermining privacy, and then the model leverage multiple kernel variant of maximum mean discrepancies (MK-MMD) to fine-tune the global model, which makes the model adapted to the specific house’s prediction task. Experimental results on the real residential datasets show that DFA has the best forecasting performance compared with other baseline models and the federated architecture of DFA has a remarkable superiority in computation time. The framework of DFA is extended with alternative transfer learning methods and all of them achieve good performances on STLF.
A Microwave-Based Microfluidic Cell Detecting Biosensor for Biological Quantification Using the Metallic Nanowire-Filled Membrane Technology
Authors: Amanati Shahri Atena , Omidvar Amir Hossein , Pamplona Rehder Gustavo , Serrano Ariana Lacorte Caniato
Published: April 2022

A label-free, sensitive, miniaturized sensing device was developed for detecting living cells in their flow stream. The outstanding performance of this biosensor in distinguishing living cells in cell suspension was achieved by integrating microstrip stub resonator above a microfluidic structure using the metallic nanowire-filled membrane technology. The cell suspension flows in a microfluidic channel placed between the tip of the stub resonator and its ground plane as the substrate to take advantage of the uniform and concentrated field distribution. We studied the changes in relative permittivity due to the presence of a single living cell in the phase of the transmitted signal (S21). An average variation of as much as 22.85 ± 1.65° at ~11.1 GHz is observed for the living cell sensing using this optimized device. This biosensor could detect rapid flowing cells in their biological medium in real-time and hence, can be used as an early diagnosis and monitoring tool for diseases.
Near Ground Pathloss Propagation Model Using Adaptive Neuro Fuzzy Inference System for Wireless Sensor Network Communication in Forest, Jungle and Open Dirt Road Environments
Authors: Hakim Galang P. N. , Habaebi Mohamed Hadi , Toha Siti Fauziah , Islam Mohamed Rafiqul , Yusoff Siti Hajar Binti , Adesta Erry Yulian Triblas , Anzum Rabeya
Published: April 2022

In Wireless Sensor Networks which are deployed in remote and isolated tropical areas; such as forest; jungle; and open dirt road environments; wireless communications usually suffer heavily because of the environmental effects on vegetation; terrain; low antenna height; and distance. Therefore; to solve this problem; the Wireless Sensor Network communication links must be designed for their best performance using the suitable electromagnetic wave behavior model in a given environment. This study introduces and analyzes the behavior of the LoRa pathloss propagation model for signals that propagate at near ground or that have low transmitter and receiver antenna heights from the ground (less than 30 cm antenna height). Using RMSE and MAE statistical analysis tools; we validate the developed model results. The developed Fuzzy ANFIS model achieves the lowest RMSE score of 0.88 at 433 MHz and the lowest MAE score of 1.61 at 433 MHz for both open dirt road environments. The Optimized FITU-R Near Ground model achieved the lowest RMSE score of 4.08 at 868 MHz for the forest environment and lowest MAE score of 14.84 at 868 MHz for the open dirt road environment. The Okumura-Hata model achieved the lowest RMSE score of 6.32 at 868 MHz and the lowest MAE score of 26.12 at 868 MHz for both forest environments. Finally; the ITU-R Maximum Attenuation Free Space model achieved the lowest RMSE score of 9.58 at 868 MHz for the forest environment and the lowest MAE score of 38.48 at 868 MHz for the jungle environment. These values indicate that the proposed Fuzzy ANFIS pathloss model has the best performance in near ground propagation for all environments compared to other benchmark models.
Developing Broadband Microstrip Patch Antennas Fed by SIW Feeding Network for Spatially Low Cross-Polarization Situation
Authors: Karami Farzad , Boutayeb Halim , Amn-e-Elahi Ali , Ghayekhloo Alireza , Talbi Larbi
Published: April 2022

A stacked multi-layer substrate integrated waveguide (SIW) microstrip patch antenna with broadband operating bandwidth and low cross-polarization radiation is provided. A complete study on the propagating element bandwidth and cross polarization level is presented to demonstrate the importance of the design. The proposed antenna includes three stacked printed circuit board (PCB) layers, including one layer for the radiating 2 × 2 rectangular patch elements and two SIW PCB layers for the feeding network. There are two common methods for excitation in cavity-backed patch antennas: probe feeding (PF) and aperture coupling (AC). PF can be used to increase the bandwidth of the antenna. Although this method increases the antenna’s bandwidth, it produces a strong cross-polarized field. The AC method can be used to suppress cross-polarized fields in microstrip patch antennas. As microstrip patch antennas are inherently narrowband, the AC method has little effect on their bandwidth. This paper proposes an antenna that is simultaneously fed by AC and PF. As a result of this innovation, the operating bandwidth of the antenna has increased, and cross-polarization has been reduced. Actually, the combination of probe feeding and aperture coupling schemes leads to achieving a broadband operating bandwidth. The arrangement of radiator elements and cavities implements a mirrored excitation technique while maintaining a low cross-polarization level. In both numerical and experimental solutions, a less than −30 dB cross-polarization level has been achieved for all of the main directions. A fractional impedance bandwidth of 29.8% (10.55–14.25 GHz) for S11 < −10-dB is measured for the proposed array. Simulated and measured results illustrate good agreement. Having features like low cost, light weight, compactness, broadband, integration capabilities, and low cross-polarization level makes the designed antenna suitable for remote-sensing and satellite applications.
Evaluation of the Effects of Bunium persicum and Albendazole on Killing Hydatid Cyst Protoscolices In Vitro
Authors: Garedaghi Yagoob , Bouree Patrice , Khaki Arash , Shaarbaf Faezeh , Haji Abedin Rangraz Mehrnaz
Published: April 2022

Objectives: Hydatidosis is a parasitic disease of zoonoses and the best treatment for this parasitic disease is cryosurgery. From time immemorial, many protoscolice-destroying chemicals have been used to inhibit the distribution of protoscolices within the cyst during surgery. However, the side effects of chemical compounds and medicinal plants should always be considered. Due to the antiparasitic properties of Bunium persicum (Boiss), this study was performed to evaluate and compare the effects of B. persicum (Boiss) essential oil and albendazole on protoscolices inside hydatid cyst in vitro. Materials and Methods: In this study, the essential oil used from the desired plant seeds was prepared. Gas chromatography-mass spectrometry was performed to determine its components. Hydatid cyst protoscolices were extracted from hydatid cyst-infected livers and exposed to B. persicum (Boiss) (2.5, 5, and 10 μg/mL) for 10, 30, 60, and 120 minutes, respectively. The viability of protoscolices was measured by the effect of plant essential oil by eosin staining. Albendazole was also used as an effective antiparasitic drug in this study. Results: The amount of essential oil protoscolices at 2.5 μg/mL in 10, 30, 60, and 120 minutes was 48.5%, 68.2%, 79.5%, and 96.1%, respectively. The antiparasitic drug albendazole showed less toxic effects at similar doses at the same intervals, but both treatment groups had a significant effect (P<0.001). The highest toxic effects of essential oil were observed at a concentration of 10 μg/mL 30 minutes after treatment. For albendazole, this effect was achieved at a dose of 10 μg/mL after 2 hours. Conclusions: The results and statistical data of this study showed that the essential oil of B. persicum (Boiss) in comparison with the antiparasitic drug albendazole has an acceptable scolicide effects in hydatidosis and can be used as an alternative to scolicide compound.
The Association Between Left Atrial Strain and Left Ventricular Ejection Fraction in a 3D Heart Model in Patients With Severe Aortic Stenosis
Authors: Mohammadi Kamran , Alizadehasl Azin , Jafari Fesharaki Mehrdad , Hajizadeh Reza , Javadieh Farshad
Published: April 2022

Objectives: Aortic stenosis (AS) is a common valvular disease diagnosed in nearly 3% of adults who are older than 65 years. Echocardiography is the main modality for the diagnosis of an AS. The left atrial (LA) strain can help in a better evaluation of heart failure and predict left-side pressures. Considering that a left ventricular ejection fraction (LVEF) is an important factor for cardiologists regarding better selection of surgery treatment in these patients, the evaluation of the LA strain and LVEF, as well as their association can help physicians in a better evaluation of borderline patients who are asymptomatic with borderline LVEF. Materials and Methods: Atrial mechanics were prospectively evaluated in 43 consecutive patients with severe AS referring to Shahid Rajaee Heart Center (Tehran, Iran), echocardiography laboratory for their regular valve disease follow-ups from July 2018 to February 2019. The LA strain, the LVEF, and their association were analyzed by a 3D heart model. Results: The mean age of patients was 56.6±18.9 years. The LA strain did not have any association with age (P=0.09). In addition, no association was found among LA strains, hypertension, and smoking in patients with severe AS (P>0.05). Finally, the results showed that an LA strain had a significant association with a 3D method of LVEF (P=0.02). Conclusions: In general, an LA longitudinal strain has a significant association with a 3D LVEF in patients with severe AS and can help physicians better evaluate patients with severe AS.
MEASURING FACTORS AFFECTING JOB SATISFACTION AND ENGAGEMENT AMONG ACADEMIC STAFF AT THE TERTIARY LEVEL
Authors: Tuấn Vũ Văn , Anh Bế Hoài
Published: April 2022

Cơ chế tự chủ trường học có tác động sâu sắc đến việc chuyển đổi mô hình trường đại học từ cơ chế chủ quản sang tự chủ hoàn toàn. Như vậy, sự tái thiết tổ chức có thể gây ảnh hưởng đến sự thoả mãn công việc và cam kết gắn bó với tổ chức của nhân viên. Nghiên cứu này sẽ xem xét những nhân tố tác động đến sự thoả mãn công việc và cam kết gắn bó của nhân viên đối với nơi làm việc, với sự tham gia của 175 giảng viên trả lời phiếu điều tra do người nghiên cứu xây dựng, thông qua biểu mẫu Google. Kết quả cho thấy rằng các nhân tố nội tại của giảng viên quan trọng hơn các yếu tố bên ngoài. Sự quan tâm và hỗ trợ của tổ chức đối với sự phát triển nghề nghiệp của giảng viên sẽ tạo ra một môi trường thuận lợi, cạnh tranh, hợp tác cho giảng viên cống hiến sự nghiệp của mình. Hơn nữa, kết quả cũng khẳng định rằng tâm, tầm, tài năng của lãnh đạo trường học có tính chất quyết định đối với sự phát triển bền vững của nhà trường, và cam kết gắn bó, cống hiến của giảng viên. Nghiên cứu cung cấp thông tin hữu ích cho các nhà quản trị trường học đầu tư hơn nữa vào đội ngũ giảng viên và quản trị nhà trường. Ngoài ra, cơ sở vật chất trường học cần phải cải tổ và trang bị thường xuyên đáp ứng nhu cầu dạy và học hiện đại ngày nay.
EFEK RATCHETING DALAM ANGGARAN BELANJA DAERAH PADA PEMERINTAH KABUPATEN/KOTA DI PROVINSI ACEH
Authors: MARLINA LILIS
Published: April 2022

Abstract: One pervasive aspect of target setting is the ratcheting effect that happens when targets for the current year are influenced by the difference between last year’s performance and its target. Lee and Plummer (2007) documented ratchet effect in public sector budgeting on performance based budgeting implementation. This study aims to find whether ratchet effecct occur in expenditure budgeting.The population used in this study is 23 local government district/urban in the Aceh Province with the observation period of 5 years (2010-2014). Simple Linear Regresion was used to test the hypotheses. The The result shows that ratchet effect occurs in expenditure budgeting, Keywords:  ratcheting effect, budgeting and expenditure goverment. Abstrak: Salah satu aspek yang meresap dalam pengaturan target adalah efek ratcheting yang terjadi ketika target untuk tahun berjalan dipengaruhi oleh perbedaan antara kinerja tahun lalu dan targetnya. Lee dan Plummer (2007) mendokumentasikan terjadinya efek ratchet pada penganggaran sektor publik dalam implementasi model penganggaran berbasis kinerja. Penelitian ini dilakukan untuk mengetahui adanya efek ratchet dalam anggaran belanja daerah. Populasi yang digunakan dalam penelitian ini adalah 23 pemerintah kabupaten/kota di Provinsi Aceh. Model regresi lineier sederhana digunakan untuk menguji hipotesis penelitian. Hasil penelitain membuktikan bahwa terjadi efek ratcheting dalam anggaran belanja daerah. Kata kunci: efek ratcheting, anggaran, dan belanja daerah .
PENGARUH FINANCIAL LEVERAGE TERHADAP PENGUNGKAPAN CORPORATE SOCIAL RESPONSIBILITY SERTA DAMPAKNYA TERHADAP NILAI PERUSAHAAN PADA PERUSAHAAN YANG TERMASUK DALAM INDEKS SRI-KEHATI YANG TERDAFTAR DI BURSA EFEK INDONESIA
Authors: RAHMAZANIATI LINDA
Published: April 2022

Abstract:This study aimed to examine the effect of financial leverage to corporate social responsibility disclosure and its impact on the firm value. The population in this study is index SRI-KEHATI company listed on the Indonesian Stock Exchange during the 5 years (2009-2013). The sample was selected using purposive sampling method and obtained a sample of 16 companies. The data are process by using a balanced panel data. The method of analysis used in this study were path analysis. The results of this study show that financial leverage have influence to the disclosure of corporate social responsibility. Financial leverage and disclosure of corporate social responsibility have influence to firm value. Keywords: Firm Value, Corporate Social Responsibility, Financial Leverage Abstrak: Penelitian ini bertujuan untuk menguji financial leverage terhadap pengungkapan Corporate Social Responsibility serta dampaknya terhadap nilai perusahaan. Populasi pada penelitian ini adalah perusahaan yang termasuk dalam indeks SRI-KEHATI yang terdaftar di BEI selama 5 tahun (2009-2013). Pemilihan sampel dengan menggunakan metode purposive sampling, dan diperoleh sebanyak 16 perusahaan. Data di proses dengan menggunakan balanced panel data. Metode analisis yang digunakan pada penelitian ini adalah path analysis. Hasil penelitian ini menunjukkan bahwa financial leverage berpengaruh terhadap pengungkapan CSR. Financial leverage dan pengungkapan CSR berpengaruh terhadap nilai perusahaan. Kata kunci: Nilai Perusahaan, Pengungkapan CSR, Financial Leverage
PENGARUH PROFITABILITAS DAN PERTUMBUHAN PENJUALAN TERHADAPFINANCIAL LEVERAGE SERTA DAMPAKNYA TERHADAP HARGA SAHAM PADA PERUSAHAAN YANG TERDAFTAR DI BURSA EFEK INDONESIA
Authors: VONNA SARI MAULIDA
Published: April 2022

Abstrak: Penelitian ini bertujuan untuk menguji pengaruh profitabilitas dan pertumbuhan penjualan terhadap financial leverage dan dampaknya terhadap harga saham. Populasi dalam penelitian ini adalah indeks perusahaan LQ45 yang tercatat di Bursa Efek Indonesia selama 5 tahun (2010-2014). Sampel dipilih menggunakan metode purposive sampling dan diperoleh sampel 15 perusahaan. Metode analisis yang digunakan dalam penelitian ini adalah analisis jalur. Hasil penelitian ini menunjukkan bahwa profitabilitas berpengaruh positif terhadap harga saham, sedangkan pertumbuhan penjualan dan financial leverage berpengaruh negatif terhadap harga saham. Profitabilitas memiliki pengaruh negatif terhadap financial leverage, sementara pertumbuhan penjualan berpengaruh positif terhadap financial leverage. Dan financial leverage tidak bisa memoderasi hubungan antara profitabilitas dan pertumbuhan penjualan terhadap harga saham.Kata kunci: Harga Saham, Financial Leverage, Profitabilitas, Pertumbuhan Penjualan
PENGARUH PERPUTARAN TOTAL AKTIVA, PERSEDIAAN DAN PIUTANG TERHADAP RENTABILITAS EKONOMI PADA PT. MAYORA INDAH TBK PERIODE 2011-2016
Authors: INUZULA LAKHARIS
Published: April 2022

Penelitian ini bertujuan untuk mengetahui pengaruh Perputaran Total Aktiva, Pesediaan dan Piutang terhadap Rentabilitas Ekonomi. Teknik sampling yang digunakan Penelitian ini adalah purposive sampling dan menggunakan data Sekunder. Data diperoleh berdasarkan Laporan Keuangan yang dipublikasi pada PT. Mayora Indah Tbk Periode 2011-2016 dengan jumlah sampel sebanyak 6 data sampel. Teknik analisis yang digunakan adalah Regresi Linear Berganda, uji hipotesis menggunakan t- statistik, Uji F dan uji koefisien determinasi serta f- statistic untuk menguji pengaruh secara parsial dengan level of significance 5%. Selain itu juga dilakukan uji deskriptif mengenai perkembangan usaha pada PT. Mayora Indah Tbk. Berdasarkan hasil analisis data, menunjukkan bahwa Perputaran total aktiva memiliki pengaruh positif signifikan terhadap rentabilitas ekonomi. Hal ini sesuai dengan nilai koefisien regresi variable Perputaran total aktiva (X1) adalah sebesar 27,366. Variabel Perputaran Persediaan berpengaruh positif dan signifikan terhadap Rentabilitas Ekonomi, dengan koefisien regresi sebesar 9,726. Dan variabel perputaran piutang dengan nilai koefisien sebesar 0,918. Hasil uji serentak menunjukkan bahwa Perputaran Persediaan, Perputaran Persediaan dan Perputaran Piutang berpengaruh terhadap Rentabilitas Ekonomi, dengan koefisien determinasi sebesar 0,685 .Kata Kunci :       Perputaran Total Aktiva,Perputaran Persediaan, Perputaran Piutang dan Rentabilitas Ekonomi