bluuebunny/crossref_metadata_2025 huggingface dataset:
Early Alterations of QTc in Patients with COVID-19 Treated with Hydroxychloroquine or Chloroquine in Libreville, Gabon
Authors: Ayo Bivigou Elsa , Manomba Boulingui Charlene , Bouraima Aridath , Allognon Christian , Akagha Konde Christelle , Atsame Gabrielle , Kinga Armel , Boguikouma Jean B. , Kouna Ndouongo Philomène , Bouyou Akotet Marielle K.
Published: July 2022

The objective of this study was to analyze the effect of hydroxychloroquine or chloroquine associated with azithromycin on the QTc interval in Gabonese patients treated for COVID-19. Methods: This was an observational study conducted from April to June 2020, at the Libreville University Hospital Center in Gabon. Patients admitted for COVID-19 and treated with hydroxychloroquine or chloroquine, each combined with azithromycin were included. The QTc interval was measured upon admission and 48 h after starting treatment. The primary endpoint was QTc prolongation exceeding 60 ms and/or a QTc value exceeding 500 ms at 48 h. Results: Data from 224 patients, 102 (45.5%) who received hydroxychloroquine and 122 treated with chloroquine, were analyzed. The median baseline QTc was 396 (369–419) ms. After 48 h of treatment, 50 (22.3%) patients had a significant prolongation of QTc. This tended to be more frequent in patients treated with chloroquine (n = 33; 27.0%) than in those treated with hydroxychloroquine (n = 17; 16.7%) (p = 0.06). QTc prolongation exceeding 60 ms was found in 48 (21.3%) patients, while 11 patients had a (4.9%) QTc exceeding 60 ms at admission and exceeding 500 ms after 48 h. Conclusion: Early QTc prolongation is frequent in COVID-19 patients treated with hydroxychloroquine or chloroquine in association with azithromycin.
Metamaterial Solar Absorber Based on Refractory Metal Titanium and Its Compound
Authors: Song Zijun , Ma Guolu , Yi Zao , Zhang Jianguo , Zhao Yong
Published: July 2022

Metamaterials refers to a class of artificial materials with special properties. Through its unique geometry and the small size of each unit, the material can acquire unique electromagnetic field properties that conventional materials do not have. Based on these factors, we put forward a kind of high absorption near-ultraviolet to near-infrared electromagnetic wave absorber of the solar energy. The surface structure of the designed absorber is composed of TiN-TiO2-Al2O3 with rectangles and disks, and the substrate is Ti-Al2O3-Ti layer. In the study band range (0.1–3.0 μm), the solar absorber’s average absorption is up to 96.32%, and the designed absorber absorbs more than 90% of the electromagnetic wave with a wavelength width of 2.577 μm (0.413–2.990 μm). Meanwhile, the designed solar absorber has good performance under different angles of oblique incident light. Ultra-wideband solar absorbers have great potential in light absorption related applicaitions because of their wide spectrum high absorption properites.
Cationic Covalent Organic Framework as Separator Coating for High-Performance Lithium Selenium Disulfide Batteries
Authors: Wang Jun , Ke Jing-Ping , Wu Zhen-Yi , Zhong Xiao-Na , Zheng Song-Bai , Li Yong-Jun , Zhao Wen-Hua
Published: July 2022

Selenium disulfide that combines the advantages of S and Se elements is a new material for Li-chalcogen battery cathodes. However, like Li-S batteries, the shuttle effect seriously restricts the performance of Li-SeS2 batteries. In this work, we have synthesized a kind of nitrogen-rich lithophilic covalent organic framework (ATG-DMTZ-COF) as a separator coating material for Li-SeS2 batteries. Here, the N atom in the ATG-DMTZ-COF channel preferentially interacts with the lithium ion in the electrolyte to form N…Li bond, which significantly improves the diffusion coefficient of lithium ions during the charge and discharge. More importantly, we prove that the pore size of ATG-DMTZ-COF will decrease sharply because there is a large amount of TFSI- in the channel, and finally the shuttling of polysulfide and polyselenide is suppressed by the sieving effect. As a consequence, Li-SeS2 batteries using the ATG-DMTZ-COF separator coating show excellent performances with an initial discharge capacity of 1028.7 mAh g−1 at 0.5 C under a SeS2 loading of 2.38 mg cm−2. Furthermore, when the current density is 1C, the specific capacity of 404.7 mAh g−1 can be maintained after 700 cycles.
3-(N,N-Diphenylamino)carbazole Donor Containing Bipolar Derivatives with Very High Glass Transition Temperatures as Potential TADF Emitters for OLEDs
Authors: Tavgeniene Daiva , Beresneviciute Raminta , Blazevicius Dovydas , Krucaite Gintare , Jacunskaite Greta , Sudheendran Swayamprabha Sujith , Jou Jwo-Huei , Grigalevicius Saulius
Published: July 2022

Well-defined electroactive bipolar derivatives of new structure have been synthesized from 3-(N,N-diphenylamino)-9H-carbazole and bis(4-fluorophenyl)sulfone, 4-fluorophenylsulfone or 4,4′-difluorobenzophenone, respectively. The full characterization of their structure is described. The amorphous materials with very high glass transition temperatures of 111–173 °C also possess high thermal stability, with onset decomposition temperatures of 351–398 °C. Some of the compounds having the best solubility were tested as the emitters dispersed in 4,4′-bis(N-carbazolyl)-1,1′-biphenyl (CBP) host for preparation of organic light emitting diodes (OLEDs). A device containing 15 wt% of the guest bis[4-{3-(N,N-diphenylamino)carbazol-9-yl}phenyl] sulfone demonstrated the best overall characteristics with maximum brightness exceeding 2630 cd/m2, current efficiency of 3.2 cd/A, power efficiency of 2.2 lm/W, and external quantum efficiency exceeding 1.7% at 100 cd/m2.
Characterization of ZTA Composite Ceramic/Ti6Al4V Alloy Joints Brazed by AgCu Filler Alloy Reinforced with One-Dimensional Al18B4O33 Single Crystal
Authors: Wang Yifeng , Jin Zhouxin , Feng Guangjie , Cao Jian , Zhang Hao , Deng Dean
Published: July 2022

Al18B4O33 whiskers were used as a reinforcer to study the effect of one-dimensional single crystal on the quality improvement of ZTA composite ceramic/Ti6Al4V alloy joints brazed by AgCu alloy. The microstructure of the joint with whisker additions was characterized in detail. The effects of brazing temperature on the microstructure and shear strength of the brazed joints were investigated. The results showed that the whiskers reacted with the liquid alloy during the brazing process and continuous (Cu,Al)3Ti3O layers were formed in contact with the residual whiskers. The addition of 2 wt.% Al18B4O33 whiskers into AgCu filler alloy can delay the growth of the (Cu,Al)3Ti3O layer on the ZTA side, and can significantly restrain the growth of the Ti-Cu compound region over a brazing temperature range of 800~875 °C. Because of the one-dimensional reinforcement, the temperature window for obtaining ZTA/Ti6Al4V joints with shear strength values higher than 50 MPa was extended, and the maximum shear strength of the joints reached 56 MPa.
Evolution of a Systematic Approach to Smoking Cessation in Ontario’s Regional Cancer Centres
Authors: Cameron Erin , Lee Vicki , Rana Sargam , Haque Mohammad , Schwartz Naomi , Khan Sahara , Truscott Rebecca , Rabeneck Linda
Published: July 2022

Smoking cessation after a cancer diagnosis can significantly improve a person’s prognosis, treatment efficacy and safety, and quality of life. In 2012, Cancer Care Ontario (now part of Ontario Health) introduced a Framework for Smoking Cessation, to be implemented for new ambulatory cancer patients at the province’s 14 Regional Cancer Centres (RCCs). Over time, the program has evolved to become more efficient, use data for robust performance management, and broaden its focus to include new patient populations and additional data collection. In 2017, the framework was revised from a 5As to a 3As brief intervention model, along with an opt-out approach to referrals. The revised model was based on emerging evidence, feedback from stakeholders, and an interim program evaluation. Results showed an initial increase in referrals to cessation services. Two indicators (tobacco use screening and acceptance of a referral) are routinely monitored as part of Ontario Health’s system-wide performance management approach, which has been identified as a key driver of change among RCCs. Due to the COVID-19 pandemic, many RCCs reported a decrease in these indicators. RCCs that were able to maintain a high level of smoking cessation activities during the pandemic offer valuable lessons, including the opportunity to swiftly leverage virtual care. Future directions for the program include capturing data on cessation outcomes and expanding the intervention to new populations. A focus on system recovery from COVID-19 will be paramount. Smoking cessation must remain a core element of high-quality cancer care, so that patients achieve the best possible health benefits from their treatments.
Advances in Nematode Identification: A Journey from Fundamentals to Evolutionary Aspects
Authors: Bhat Kaisar Ahmad , Mir Rakeeb Ahmad , Farooq Asmat , Manzoor Madhiya , Hami Ammarah , Allie Kaisar Ahmad , Wani Shaheen Majeed , Khan M. N. , Sayyed R. Z. , Poczai Peter , Almalki Waleed Hassan , Zargar Sajad Majeed , Shah Ali Asghar
Published: July 2022

Nematodes are non-segmented roundworms evenly distributed with various habitats ranging to approximately every ecological extremity. These are the least studied organisms despite being the most diversified group. Nematodes are the most critical equilibrium-maintaining factors, having implications on the yield and health of plants as well as well-being of animals. However, taxonomic knowledge about nematodes is scarce. As a result of the lack of precise taxonomic features, nematode taxonomy remains uncertain. Morphology-based identification has proved inefficacious in identifying and exploring the diversity of nematodes, as there are insufficient morphological variations. Different molecular and new evolving methodologies have been employed to augment morphology-based approaches and bypass these difficulties with varying effectiveness. These identification techniques vary from molecular-based targeting DNA or protein-based targeting amino acid sequences to methods for image processing. High-throughput approaches such as next-generation sequencing have also been added to this league. These alternative approaches have helped to classify nematodes and enhanced the base for increased diversity and phylogeny of nematodes, thus helping to formulate increasingly more nematode bases for use as model organisms to study different hot topics about human well-being. Here, we discuss all the methods of nematode identification as an essential shift from classical morphometric studies to the most important modern-day and molecular approaches for their identification. Classification varies from DNA/protein-based methods to the use of new emerging methods. However, the priority of the method relies on the quality, quantity, and availability of nematode resources and down-streaming applications. This paper reviews all currently offered methods for the detection of nematodes and known/unknown and cryptic or sibling species, emphasizing modern-day methods and budding molecular techniques.
Birds in Temperate and Tropical Forests: Introduction to the Special Issue
Authors: Riegert Jan
Published: July 2022

Globally, forests are the most threatened habitats, especially due to tree logging and other disturbances caused mainly by humans [...]
Correction: Rizzo et al. Artificial Intelligence and OCT Angiography in Full Thickness Macular Hole. New Developments for Personalized Medicine. Diagnostics 2021, 11, 2319
Authors: Rizzo Stanislao , Savastano Alfonso , Lenkowicz Jacopo , Savastano Maria Cristina , Boldrini Luca , Bacherini Daniela , Falsini Benedetto , Valentini Vincenzo
Published: July 2022

In the original publication [...]
Value of Clinical Information on Radiology Reports in Oncological Imaging
Authors: Schön Felix , Sinzig Rebecca , Walther Felix , Radosa Christoph Georg , Nebelung Heiner , Eberlein-Gonska Maria , Hoffmann Ralf-Thorsten , Kühn Jens-Peter , Blum Sophia Freya Ulrike
Published: July 2022

Radiological reporting errors have a direct negative impact on patient treatment. The purpose of this study was to investigate the contribution of clinical information (CI) in radiological reporting of oncological imaging and the dependence on the radiologists’ experience level (EL). Sixty-four patients with several types of carcinomas and twenty patients without tumors were enrolled. Computed tomography datasets acquired in primary or follow-up staging were independently analyzed by three radiologists (R) with different EL (R1: 15 years; R2: 10 years, R3: 1 year). Reading was initially performed without and 3 months later with CI. Overall, diagnostic accuracy and sensitivity for primary tumor detection increased significantly when receiving CI from 77% to 87%; p = 0.01 and 73% to 83%; p = 0.01, respectively. All radiologists benefitted from CI; R1: 85% vs. 92%, p = 0.15; R2: 77% vs. 83%, p = 0.33; R3: 70% vs. 86%, p = 0.02. Overall, diagnostic accuracy and sensitivity for detecting lymphogenous metastases increased from 80% to 85% (p = 0.13) and 42% to 56% (p = 0.13), for detection of hematogenous metastases from 85% to 86% (p = 0.61) and 46% to 60% (p = 0.15). Specificity remained stable (>90%). Thus, CI in oncological imaging seems to be essential for correct radiological reporting, especially for residents, and should be available for the radiologist whenever possible.
Odontogenic Sinusitis: From Diagnosis to Treatment Possibilities—A Narrative Review of Recent Data
Authors: Martu Cristian , Martu Maria-Alexandra , Maftei George-Alexandru , Diaconu-Popa Diana Antonela , Radulescu Luminita
Published: July 2022

The maxillary sinus is a structure at the border of specialties: otorhinolaryngology and maxillofacial surgery. Due to this fact, regarding etiology, it can be affected by both the rhinogenic and odontogenic path and can impose diagnostic difficulties. The etiopathogenic mechanisms that can affect the Schneiderian membrane are mainly inflammatory, iatrogenic, traumatic, and tumorous in nature. From a microbiological point of view, the bacteriology is polymorphic, including both aerobic and anaerobic species in acute OS, the predominating species in acute OS being aerobic, and in chronic anaerobic germs. The role of fungi in the determination of this pathology and in the production of the biofilm that leads to resistance to antibiotic treatment is also discussed. The present paper aims to present the etiopathogenesis, bacteriology, clinical manifestations, as well as treatment of odontogenic sinusitis (OS) from an updated perspective through reviewing the literature. If unilateral maxillary sinusitis is usually due to odontogenic causes, this does not clinically exclude the possibility of strictly rhinogenic causes in the occurrence of sinusitis. This underlines the important role of complex oral and rhinological clinical examination as well as the role of preclinical examinations in specifying the certainty diagnosis. Simple radiography, orthopantomography, CT, and CBCT are compared in terms of diagnostic accuracy. The treatment of OS is complex, involving medication, dental, and surgical measures. The value of endoscopic surgery is emphasized, comparing its advantages over the classic Caldwell-Luc technique.
The Spatial Distribution of Renal Fibrosis Investigated by Micro-probe Terahertz Spectroscopy System
Authors: Li Han , Ding Jiarong , Zhang Huan , Li Maoting , Lai Xueli
Published: July 2022

Renal fibrosis, which is characterized as progressive extracellular matrix accumulation, is a common feature of different stages of chronic kidney disease, and the degree of fibrosis is strongly associated with renal function. In clinical practice, precise understanding of the space distribution of fibrosis is extremely important for the diagnosis and prognosis of renal disease. Rapid advances in terahertz (THz) technology have been made, and this technology has a broad application in bio-detection, as it can interact and measure the collective vibrations and rotations of molecular groups. It is well known that hydroxyproline (HYP) is the key component of collagen, which is synthesized by fibroblasts to maintain the extracellular matrix, and HYP content detection in tissue homogenate can be achieved by classical biochemistry method. In this study, a THz microprobe system was employed to conduct THz microspatial scanning with a resolution of 20 µm. Both the content and distribution of HYP were directly characterized by the THz absorption spectrum. The absorption intensity in the THz spectrum was used to determine HYP density in renal tissues; therefore, the fibrosis change in the kidneys can be determined using THz scanning at micrometer resolution, which provides more possibilities for precise diagnosis of renal fibrosis.
Evaluation of Respiratory Particle Emission during Otorhinolaryngological Procedures in the Context of the SARS-CoV-2 Pandemic
Authors: Veltrup Reinhard , Kniesburges Stefan , Döllinger Michael , Falk Sebastian , Mueller Sarina K.
Published: July 2022

Understanding the risk of infection by routine medical examination is important for the protection of the medical personnel. In this study we investigated respiratory particles emitted by patients during routine otolaryngologic procedures and assessed the risks for the performing physician. We developed two experimental setups to measure aerosol and droplet emission during rigid/flexible laryngoscopy, rhinoscopy, pharyngoscopy, otoscopy, sonography and patient interview for subjects with and without masks. A high-speed-camera setup was used to detect ballistic droplets (approx. > 100 µm) and an aerosol-particle-sizer was used to detect aerosol particles in the range of 0.3 µm to 10 µm. Aerosol particle counts were highly increased for coughing and slightly increased for heavy breathing in subjects without masks. The highest aerosol particle counts occurred during rigid laryngoscopy. During laryngoscopy and rhinoscopy, the examiner was exposed to increased particle emission due to close proximity to the patient’s face and provoked events such as coughing. However, even during sonography or otoscopy without a mask, aerosol particles were expelled close to the examiner. The physician’s exposure to respiratory particles can be reduced by deliberate choice of examination technique depending on medical indication and the use of appropriate equipment for the examiners and the patients (e.g., FFP2 masks for both).
Gene Expression Profile of Stromal Factors in Cancer-Associated Fibroblasts from Prostate Cancer
Authors: Eiro Noemi , Fernández-Gómez Jesús María , Gonzalez-Ruiz de León Cristina , Fraile Maria , Gonzalez-Suarez Jorge , Lobo-Rodríguez Beatriz , García-Rodríguez Jorge , Escaf Safwan , Vizoso Francisco J.
Published: July 2022

Recent investigations point at the stromal microenvironment to assess additional diagnostic information and provide new therapeutic targets in cancer. The aim of the study was to contribute to the characterization of the phenotype of cancer-associated fibroblasts (CAFs) in prostate cancer (PCa) compared with normal prostate-associated fibroblasts (NAFs) and fibroblasts from benign prostatic hyperplasia (BPH). Three patient populations were prospectively recruited: 23 patients with new localized PCa, 14 patients with advanced PCa treated with androgenic deprivation therapy (ADT), and 7 patients with BPH. Gene expression of 20 stroma-derived factors, including the androgen receptor (AR), chaperones (HSPA1A and HSF1), growth factors (FGF2, FGF7, FGF10, HGF, PDGFB, and TGFβ), proteins implicated in invasion (MMP2, MMP9, and MMP11), inflammation (IL6, IL17RB, NFκB, and STAT3), and in-stroma/epithelium interaction (CDH11, CXCL12, CXCL14, and FAP), was evaluated. Localized PCa CAFs showed a significant higher expression of FGF7, IL6, MMP2, and MMP11 compared with NAFs or IL17RB compared with BPH fibroblasts, but significantly lower expression of FGF10 and IL17RB compared with NAFs or CXCL14 compared with BPH fibroblasts. In addition, CAFs from ADT-resistant PCa showed significantly higher MMP11 and NFκB but significant lower TGFβ expression compared with CAFs from ADT-sensitive tumors. Our results contribute to defining the CAFs phenotypes associated to PCa progression, which may contribute to the diagnosis and design of alternative therapies in PCa.
Fungal Prosthetic Joint Infection in Revised Knee Arthroplasty: An Orthopaedic Surgeon’s Nightmare
Authors: Koutserimpas Christos , Naoum Symeon , Alpantaki Kalliopi , Raptis Konstantinos , Dretakis Konstantinos , Vrioni Georgia , Samonis George
Published: July 2022

Fungal prosthetic joint infections (PJIs), despite the fact that they are rare, represent a devastating complication. Such infections in revised knee arthroplasties pose a unique surgical and medical challenge. A rare case of Candida parapsilosis PJI in revised knee arthroplasty is reported. Furthermore, a thorough review of all published fungal PJIs cases in revised knee arthroplasties is provided. A 72-year-old female with total knee replacement surgery due to osteoarthritis 10 years ago, followed by two revision surgeries six and two years ago due to aseptic loosening, presented with signs and symptoms of septic loosening of the knee components. Resection arthroplasty and cement-spacer placement was performed and periprosthetic tissue cultures yielded Candida parapsilosis. The patient was commenced on proper antifungal treatment (AFT) for six months and then the second stage of the revision surgery was performed successfully. From 2000 to 2022, a total of 46 patients with median age 69 years [interquartile range (IQR = 10)], suffering fungal PJI occurring in revised knee arthroplasty have been reported. The median time from initial arthroplasty to symptoms’ onset was 12 months (IQR = 14). Cultures of local material (52.2%) and histology (6.5%) were the reported diagnostic method, while Candida species were the most commonly isolated fungi. Regarding surgical management, two-stage revision arthroplasty (TSRA) was performed in most cases (54.3%), with median time-interval of six months (IQR = 6) between the two stages. Regarding AFT, fluconazole was the preferred antifungal compound (78.3%), followed by voriconazole and amphotericin B (19.6% each). The median duration of AFT was five months (IQR = 4.5). Infection’s outcome was successful in 38 cases (82.6%). Fungal PJIs, especially in revised knee arthroplasties, are devastating complications. A combination of AFT and TSRA seems to be the treatment of choice. TSRA in these cases poses a special challenge, since major bone defects may be present. Therapeutic procedures remain unclear, thus additional research is needed.
Plasma Nickel Levels Correlate with Low Muscular Strength and Renal Function Parameters in Patients with Prostate Cancer
Authors: Alegre-Martínez Antoni , Martínez-Martínez María Isabel , Rubio-Briones José , Cauli Omar
Published: July 2022

Nickel is associated with cancer in occupational exposure. However, few studies have been devoted to analyzing the effects of nickel at environmental concentrations in cancer patients. In this work, the concentration of nickel in blood samples from patients with prostate cancer (PCa) was evaluated because this metal displays androgenic and estrogenic effects that play a crucial role in prostate carcinogenesis and treatment. We, therefore, compared blood nickel concentration in patients with PCa (non-occupationally exposed) (n = 46) with those in control age-matched individuals (n = 46). We also analyzed if there was any association between sociodemographic factors, clinical variables, geriatric evaluation assessment results, blood cell counts, or biochemical, androgen and estrogen concentrations. Using inductively coupled plasma-mass spectroscopy on the plasma samples, we observed a mean nickel level of 4.97 ± 1.20 µg/L in the PCa group and 3.59 ± 0.49 µg/L in the control group, with a non-significant effect (p = 0.293) between the two groups. The nickel concentration was significantly correlated with patient age (p = 0.005) and reduced handgrip strength (p = 0.003). Regarding biochemical parameters, significant associations were found with the renal glomerular filtration rate (p = 0.024) and blood urea levels (p = 0.016). No significant correlations were observed with other blood analytical parameters or testosterone or estradiol levels. These specific renal function and muscle strength effects were observed at environmental nickel exposure levels believed to be safe or at least far from the high concentrations observed after occupational exposure. Therefore, these parameters deserve further study, given that they could help pinpoint further public health concerns regarding nickel exposure in the general population.
Full-Arch Rehabilitation Using Trans-Mucosal Tissue-Level Implants with and without Implant-Abutment Units: A Case Report
Authors: Carossa Massimo , Alovisi Mario , Crupi Armando , Ambrogio Giulia , Pera Francesco
Published: July 2022

Recently, tissue-level implants with a convergent collar have been introduced. While different studies have investigated the outcomes of this implant design in the rehabilitation of single teeth, its use in full-arch rehabilitation has yet to be investigated. The present case report describes the clinical outcomes of a full-arch immediate loading rehabilitation using tissue-level implants, with and without using implant-abutment units, with 2 years of follow-up. A female patient with mandibular terminal dentition and a high level of bone resorption (distal areas with a few millimeters of residual bone in the vertical dimension and both distal and anterior areas with narrow crestal bone in the horizontal dimension) was seen at the C.I.R Dental School, Turin, Italy. The patient was seeking to be rehabilitated with fixed prosthodontics, and she was found eligible for an immediate loading implant full-arch rehabilitation. Four implants were inserted in the same appointment. The two anterior implants were inserted straight and connected directly to the prosthesis (no abutments); the two distal implants were tilted in order to avoid the alveolar nerve and connected to two 30° angulated abutments. Two years post-implant placement, all of the implants were successfully integrated, resulting in an implant survival rate of 100%. The peri-implant soft tissues were stable at all the implant sites. No differences were highlighted between those implants with and without abutments. Within the limitations of the present clinical report, implant full-arch rehabilitations with tissue-level implants both with and without implant-abutment units showed optimal outcomes after two years of follow-up. Further research is encouraged to confirm whether this implant design may be a valid alternative to traditional implants in this type of rehabilitation, with or without implant-abutment units.
A Locust-Inspired Model of Collective Marching on Rings
Authors: Amir Michael , Agmon Noa , Bruckstein Alfred M.
Published: July 2022

We study the collective motion of autonomous mobile agents in a ringlike environment. The agents’ dynamics are inspired by known laboratory experiments on the dynamics of locust swarms. In these experiments, locusts placed at arbitrary locations and initial orientations on a ring-shaped arena are observed to eventually all march in the same direction. In this work we ask whether, and how fast, a similar phenomenon occurs in a stochastic swarm of simple locust-inspired agents. The agents are randomly initiated as marching either clockwise or counterclockwise on a discretized, wide ring-shaped region, which we subdivide into k concentric tracks of length n. Collisions cause agents to change their direction of motion. To avoid this, agents may decide to switch tracks to merge with platoons of agents marching in their direction. We prove that such agents must eventually converge to a local consensus about their direction of motion, meaning that all agents on each narrow track must eventually march in the same direction. We give asymptotic bounds for the expected time it takes for such convergence or “stabilization” to occur, which depends on the number of agents, the length of the tracks, and the number of tracks. We show that when agents also have a small probability of “erratic”, random track-jumping behavior, a global consensus on the direction of motion across all tracks will eventually be reached. Finally, we verify our theoretical findings in numerical simulations.
Skills Development through Virtual Art-Based Learning: Learning Outcomes of an Advanced Training Program for Project Managers
Authors: Sandberg Berit , Stasewitsch Elena , Prümper Jochen
Published: July 2022

With regard to emerging requirements of the professional field, uncertainty competence is a skill to be cultivated and integrated into project management education and training. Art-based learning seems to be a promising approach because the artistic mindset is a suitable model for coping with uncertainty. However, it is widely unclear to what extent art-based learning’s experiential nature will result in soft skills development under the restrictions of distance education. The present quantitative study explores whether—in a virtual learning environment—art-based executive training has a measurable effect on uncertainty competence. Data collection and analysis applied a quasi-experimental pretest-posttest control group design. Participants in the experimental group completed a month-long virtual training program based on visual arts. Contrary to its objective, the program did not cause meaningful changes in uncertainty competence or perceived stress but had a significant effect on participants’ attentiveness and presence. Participants achieved a higher level of mindfulness in dealing with complexity. The results imply that—even in virtual settings—art-based approaches enhance perceptive capacity and social presence but need to be long-term, related to participants’ individual work-context, and disturb participants’ routines to have an effect on uncertainty competence.
Research Trends and Development Perspectives in Early Childhood Science Education: An Overview
Authors: Ravanis Konstantinos
Published: July 2022

This article serves as a critical approach to both the emergence and the identity formation of Early Childhood Science Education (ECSE) as a new scientific field, consolidated within the association of certain research divisions of Early Childhood Education, various branches of Psychology dealing with learning, and of Science Education. Consequently, we present research trends, orientations, and currents in ECSE, such as the study of children’s mental representations, the development of teaching activities, teachers’ perspectives, the preparation of teaching materials, scientific skills, diversity and inclusive education, the influence of the family, etc. Finally, we formulate some concluding remarks on research perspectives and the epistemological formation of ECSE.
An Efficient Framework with Node Filtering and Load Expansion for Machine-Learning-Based Hardware Trojan Detection
Authors: Dong Meng , Pan Weitao , Qiu Zhiliang , Gao Yiming , Qi Xiaoxin , Zheng Ling
Published: July 2022

The globalization of the integrated circuit (IC) industry has raised concerns about hardware Trojans (HT), and there is an urgent need for efficient HT-detection methods of gate-level netlists. Machine learning (ML) is a powerful tool for this purpose. A Trojan-detection framework is proposed in this paper to solve the data imbalance and low accuracy problems of existing ML-based HT-detection algorithms. To solve the problem of data imbalance, we propose the node-filtering algorithm, which extracts structure templates from HT circuits and removes most normal nodes based on them. To enhance the identification of unknown HT payload, we propose the load-expansion algorithm, which expands the identified HT nodes based on their fanout features. We evaluate the framework using different ML algorithms. The results show that the framework significantly improves the Trojan-detection rate of the original algorithms, and achieves a 10% improvement in true positive rate compared to the original algorithms.
Ultra-Wideband Pentagonal Fractal Antenna with Stable Radiation Characteristics for Microwave Imaging Applications
Authors: Khan Muhammad Abbas , Rafique Umair , Savci Hüseyin Şerif , Nordin Anis Nurashikin , Kiani Saad Hassan , Abbas Syed Muzahir
Published: July 2022

For microwave imaging applications, a design for an ultra-wideband (UWB) fractal antenna is presented. The antenna design is composed of a pentagonal fractal patch radiator fed by a modified co-planar waveguide (CPW) ground plane. It is built on a low-loss Rogers RT/Duroid 5880 dielectric substrate with a dimensions of 24 × 30 × 0.787 mm3. According to the measurements, the designed antenna offers a fractional bandwidth of 123.56% ranging from 3 GHz to 12.7 GHz. In addition, a maximum gain of 3.6 dBi is achieved at 8.5 GHz. From the results, it is also observed that the proposed antenna structure attains constant radiation characteristics in the operating bandwidth, which is useful for microwave imaging applications. The time domain analysis of the proposed design is also performed, and it is observed that the designed antenna offers a group delay of ≤1.5 ns, which ensures minimum pulse distortion.
Application of Model-Based Software Testing in the Health Care Domain
Authors: Jha Pragya , Sahu Madhusmita , Bisoy Sukant Kishoro , Sain Mangal
Published: July 2022

The human body’s reaction to various therapeutic medications is critical to comprehend since it aids in the appropriate construction of automated decision support systems for healthcare. Healthcare Internet of Things (IoT) solutions are becoming more accessible and trusted, necessitating more testing before they are standardized for commercial usage. We have developed an activity diagram based on the Unified Modeling Language (UML) to represent acceptability testing in IoT systems. The activity flow graph is used to extract all of the necessary information by traversing the activity flow diagram from start to finish, displaying all its properties. In this paper, a test case is generated to compute the type of diabetes using blood sugar test results, estimate the kind of diabetes, and the probability that a person would get diabetes in the future. We have demonstrated how these test cases can function using a telehealth care case study. First, we offer a high-level overview of the topic as well as a design model working diagram. The test case creation method is then outlined using the activity diagram as a guide.
Long-Term Thermal Cycling Test and Heat-Charging Kinetics of Fe-Substituted Mn2O3 for Next-Generation Concentrated Solar Power Using Thermochemical Energy Storage at High Temperatures
Authors: Gokon Nobuyuki , Hayashi Kosuke , Sawaguri Hiroki , Ohashi Fumiya
Published: July 2022

We studied the performance in terms of the long-term cyclic thermal storage and heat-charging kinetics of Fe-substituted manganese oxide for use in thermochemical energy storage at temperatures exceeding 550 °C in a next-generation concentrated solar power system in which a gas stream containing oxygen is used for reversible thermochemical processes. The Fe-substituted Mn2O3 was evaluated from the viewpoint of its microstructural characteristics, thermodynamic phase transitions, and long-term cycling stability. A kinetic analysis of the heat-charging mode was performed at different heating rates to formulate the kinetic equation and describe the reaction mechanism by determining the appropriate reaction model. Finally, the kinetics data for the sample obtained after the long-term cycling test were compared and evaluated with those of the as-prepared sample and kinetic literature data tested under different conditions. For the long-term cycled sample, the Avrami–Erofeev reaction model (An) with n = 2 describes the behavior of the first part of the charging mode, whereas the contracting area (R2) reaction model best fits the last half of the charging mode. For the as-prepared sample, except for the early stage of the charging mode (fractional conversion < 0.2), the contracting volume (R3) reaction model fits the charging mode over a fractional conversion range of 0.2–1.0 and the first-order (F1) reaction model fits in the fractional conversion range of 0.4–1.0. The predicted kinetic equations for both the samples were in good agreement with the experimental kinetic data.
A Comparative Study of Robust MPC and Stochastic MPC of Wind Power Generation System
Authors: Liu Xiangjie , Feng Le , Kong Xiaobing
Published: July 2022

In this paper, a complete comparison analysis of two advanced control algorithms, namely robust model predictive control (MPC) and stochastic MPC, is performed in order to optimize the operation of a wind power generation system (WPGS). The power maximization often conflicts with the mechanical load experienced by the turbine in the full-load region (i.e., the higher the power extracted, the higher the load) under the wind speed disturbance, thereby leading to high maintenance cost resulting from the fatigue damage. Thus, a typical 5 MW wind turbine operating in a high-speed region is considered to guarantee system security and economy. The robust MPC is designed by utilizing the min–max framework to track steady-state optimum operating reference trajectory with the deterministic constraint of output power, while the stochastic MPC is constructed by incorporating the invariant set theory to also ensure the system security subjecting to the probabilistic constraint of output power. The relation between the constraints and the implications on optimal performance are also studied. Comprehensive simulations on a mechanism model and FAST simulator are carried out to demonstrate the validation of the two control methods under various scenarios. It is discovered that when wind speed in the near future can be predicted and utilized in controller design, the stochastic MPC can effectively reduce the maintenance cost by suppressing the constraint violation rate compared to robust MPC with a similar energy utilization due to the incorporation of the stochastic characteristics of wind speed.
Steam Cavity Expansion Model for Steam Flooding in Deep Heavy Oil Reservoirs
Authors: Zhang Lina , Du Dianfa , Zhang Yaozu , Liu Xin , Fu Jingang , Li Yuan , Ren Jianhua
Published: July 2022

Steam flooding is crucial for the development of heavy oil reservoirs, and the development of the steam cavity significantly determines the efficiency of steam flooding. Previous studies have elucidated the concept of steam overburden and pseudomobility ratio; however, the thermal energy loss in deep heavy oil reservoirs during steam injection needs further investigation. Therefore, in this study, the vapour–liquid interface theory and mathematical integration were used to establish a steam cavity expansion model. The wellbore heat loss rate coefficient, steam overlay, and pseudomobility ratio were used to accurately describe the development of the steam cavity in deep heavy oil reservoirs. The proposed model was experimentally validated, and it was observed that the model could accurately reflect the actual mine conditions. In addition, the pressure gradient distribution of the steam belt and the heat dissipation areas of the top and bottom layers of the steam cavity were evaluated. The results showed that the influence of the wellbore heat loss rate coefficient on the pressure gradient of the oil layer was primarily in the range of 5–20 m away from the steam injection well. Furthermore, it was observed that the pseudomobility ratio is inversely proportional to the development of the steam cavity. As the wellbore heat loss rate coefficient increased, the wellbore heat loss increased. The larger the area ratio, the more pronounced the steam overlay phenomenon, and the large area ratio does not meet the development requirements of the steam chamber. The research closely combines theory with production, and the results of this study can help actual mines by providing theoretical support for the development of deep heavy oil reservoirs.
Augmentation of DFIG and PMSG Wind Turbines Transient Performance Using Different Fault Current Limiters
Authors: Okedu Kenneth
Published: July 2022

The technology of variable speed wind turbines is very promising in renewable power generation. It is imperative for wind turbines to gain control after grid disturbances and contribute to the stability of power grids as part of the requirements of grid codes set by grid operators in operating wind farms. Fault current limiters (FCLs) are capable of augmenting the performance of wind turbines during grid disturbances. In this article, the augmentation of the Doubly Fed Induction Generator (DFIG) and the Permanent Magnet Synchronous Generator (PMSG) wind turbines, which are the two most popular variable speed wind turbines, is presented. The evaluation of both wind turbines was performed considering the Series Dynamic Braking Resistor (SDBR), Bridge Fault Current Limiter (BFCL) and the Capacitive Bridge Fault Current Limiter (CBFCL). The modeling of the FCLs in the wind turbines was derived for steady state and grid disturbances so that their dynamic behavior could be understood. The grid voltage variable was employed as the signal for switching the FCLs in both wind turbines during grid disturbances. Moreover, a scenario with no control using the FCLs was also carried out for both wind turbines. The performance of the FCLs in both wind turbines was analyzed and compared using a severe three-phase to ground fault at their terminals. For effective comparison, the same conditions of operation were used in investigating the performance of the FCLs control strategies in both wind turbines during grid disturbances. The study was conducted using Power System Computer-Aided Design and Electromagnetic Transient including DC (PSCAD/EMTDC) environment.
Resistance and Resilience of Desert Riparian Communities to Extreme Droughts
Authors: Fu Aihong , Wang Weihua , Li Weihong , Chen Yapeng
Published: July 2022

Changes in the resistance, recovery, and resilience of three desert riparian ecosystems to extreme droughts and the influence of ecological characteristics on them from 2000 to 2020 were analyzed within the Tarim River Basin, Xinjiang, China. The results showed that: (1) The resistance of the Populus euphratica forest community was the highest among the three plant communities. The recovery and resilience of the shrub community were the highest; (2) the resilience increased the most for the shrub community and decreased slightly for the Populus euphratica forest and herb communities as hydrological droughts waned; (3) the relative height and density significantly increased for Populus euphratica, decreased for herbs, and did not change for shrubs from 2000 to 2020; (4) the diversity indexes did not significantly change for the Populus euphratica forest and herb communities, and they increased for the shrub community from 2000 to 2020; (5) the resistance and resilience of the Populus euphratica forest, shrub, and herb communities were significantly affected by ecological characteristics, especially the Margalef richness index; and (6) the shrub community is more likely to rapidly recover (that is an increase of cover, height, and density) from future droughts in the Tarim River Basin, particularly with the implementation of new and more effective ecological restoration projects.
Tissue-Specific and Differential Cold Responses in the Domesticated Cold Tolerant Fugu
Authors: Han Shuang , Wei Shang , Chen Ruoyu , Ni Man , Chen Liangbiao
Published: July 2022

Domestication can be defined as the artificial selection in animals to achieve morphological, physiological, and developmental conformity to human needs, with the aim of improving various limitations in species under a human feeding environment. The future sustainability of aquaculture may rely partly on the availability of numerous domesticated fish species. However, the underlying adaptive mechanisms that result in the domestication of fish are still unclear. Because they are poikilothermic, temperature is a key environmental element that affects the entire life of fish, so studying the association between physiological and behavioral changes in low-temperature domesticated fish can provide a model for understanding the response mechanisms of fish under cold stress. Through 5 generations and 10 years of artificial selection at low temperatures, we used cold-tolerant fugu as a biological model to compare transcriptome changes in brain and liver tissues to study the effects of cold stress on fish. It was found that the expression of genes such as apoptosis, p53, oxidative phosphorylation, and mitochondrial β-oxidation in the brain of cold-tolerant fugu was significantly lower than the wild type due to cold stress, while excessive energy metabolism would lead to the production of reactive oxygen species (ROS) and exacerbate the brain damage, thus causing rollover and coma. Meanwhile, under cold stress, the signaling pathways involved in glycogenolysis and lipid metabolism, such as insulin signaling, adipocytokines, and mTOR signaling pathways, were significantly up-regulated in the liver of cold-tolerant fugu. Although the mitochondrial β-oxidation pathway was increased in cold-tolerant fugu liver tissues, the transcriptome was not enriched in apoptotic. These phenomena predict that in response to low-temperature conditions, cold-tolerant fugu employs a dynamic inter-organ metabolic regulation strategy to cope with cold stress and reduce damage to brain tissues.
Human Adult Microbiota in a Static Colon Model: AhR Transcriptional Activity at the Crossroads of Host–Microbe Interaction
Authors: Goya-Jorge Elizabeth , Gonza Irma , Bondue Pauline , Douny Caroline , Taminiau Bernard , Daube Georges , Scippo Marie-Louise , Delcenserie Véronique
Published: July 2022

Functional symbiotic intestinal microbiota regulates immune defense and the metabolic processing of xenobiotics in the host. The aryl hydrocarbon receptor (AhR) is one of the transcription factors mediating host–microbe interaction. An in vitro static simulation of the human colon was used in this work to analyze the evolution of bacterial populations, the microbial metabolic output, and the potential induction of AhR transcriptional activity in healthy gut ecosystems. Fifteen target taxa were explored by qPCR, and the metabolic content was chromatographically profiled using SPME-GC-MS and UPLC-FLD to quantify short-chain fatty acids (SCFA) and biogenic amines, respectively. Over 72 h of fermentation, the microbiota and most produced metabolites remained stable. Fermentation supernatant induced AhR transcription in two of the three reporter gene cell lines (T47D, HepG2, HT29) evaluated. Mammary and intestinal cells were more sensitive to microbiota metabolic production, which showed greater AhR agonism than the 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) used as a positive control. Some of the SCFA and biogenic amines identified could crucially contribute to the potent AhR induction of the fermentation products. As a fundamental pathway mediating human intestinal homeostasis and as a sensor for several microbial metabolites, AhR activation might be a useful endpoint to include in studies of the gut microbiota.