bluuebunny/crossref_metadata_2025 huggingface dataset:
Behavioral and Psychological Outcomes Associated with Skin Cancer Genetic Testing in Albuquerque Primary Care
Authors: Hay Jennifer L. , Kaphingst Kimberly A. , Buller David , Schofield Elizabeth , Meyer White Kirsten , Sussman Andrew , Guest Dolores , Dailey Yvonne T. , Robers Erika , Schwartz Matthew R. , Li Yuelin , Hunley Keith , Berwick Marianne
Published: August 2021

Public availability of genetic information is increasing; thus, efforts to improve diversity in basic and translational research in genomics is a top priority. Given the increasing U.S. incidence and mortality of melanoma, and the prevalence of common melanocortin-1 receptor (MC1R) gene melanoma risk variants in the general population, we examined genomic testing of MC1R for skin cancer risk in a randomized controlled trial in Albuquerque, New Mexico primary care. Participants were 48% Hispanic and were randomized 5:1 to a MC1R test invitation or usual care. We assessed 3 month sun protection, skin cancer screening, and skin cancer worry outcomes associated with testing, and key effect moderators (e.g., cancer risk perceptions, and skin cancer risk factors). Our findings indicate that the primary outcomes were unchanged by the MC1R test offer, test acceptance, and level of risk feedback. Moderator analyses showed that those with lower risk perception, and those with skin that readily tans, significantly increased their sun protection in response to higher than average risk feedback. Risk feedback did not prompt cancer worry, and average risk feedback did not erode existing sun protection. This study paves the way for the development of tailored strategies to address low skin cancer risk awareness in this understudied context of public health genomics.
The Rarest of Rare Thymic Lesions: A 10-Year Surgical Pathology Experience
Authors: Calabrese Fiorella , Fortarezza Francesco , Pezzuto Federica , Lunardi Francesca , Comacchio Giovanni , Sbaraglia Marta , Pasello Giulia , Marulli Giuseppe , Dei Tos Angelo Paolo , Rea Federico
Published: August 2021

The thymus is a specialized primary lymphoid organ located in the midline pre-vascular mediastinum. The organ is the site of various pathological processes, neoplastic and not, whose rarity has not allowed in-depth studies on clinical or histological features of rarest and unusual variants. Herein, we report a 10-year Padova experience in the surgical pathology of the thymus, focusing on the pathological description of nonneoplastic lesions and rare epithelial and mesenchymal tumors recorded in our database, which comprises over 600 thymectomies. The extrapolated rare cases have been categorized into four groups that included 15 cysts, 18 carcinomas, 5 neuroendocrine tumors, and 2 soft tissue tumors. The cases are described from a clinical and pathological point of view and discussed in dedicated sections with a review of the most important literature. In this case, review series, we aim to update the epidemiology of these rare entities, improve diagnostic awareness, and finally, promote a collaborative network between referral centers.
Thrombospondin-1 Silencing Improves Lymphocyte Infiltration in Tumors and Response to Anti-PD-1 in Triple-Negative Breast Cancer
Authors: Marcheteau Elie , Farge Thomas , Pérès Michaël , Labrousse Guillaume , Tenet Julie , Delmas Stéphanie , Chusseau Maud , Duprez-Paumier Raphaëlle , Franchet Camille , Dalenc Florence , Imbert Caroline , Noujarède Justine , Colacios Céline , Prats Hervé , Cabon Florence , Ségui Bruno
Published: August 2021

Triple-negative breast cancer (TNBC) is notoriously aggressive with a high metastatic potential, and targeted therapies are lacking. Using transcriptomic and histologic analysis of TNBC samples, we found that a high expression of thrombospondin-1 (TSP1), a potent endogenous inhibitor of angiogenesis and an activator of latent transforming growth factor beta (TGF-β), is associated with (i) gene signatures of epithelial–mesenchymal transition and TGF-β signaling, (ii) metastasis and (iii) a reduced survival in TNBC patients. In contrast, in tumors expressing low levels of TSP1, gene signatures of interferon gamma (IFN-γ) signaling and lymphocyte activation were enriched. In TNBC biopsies, TSP1 expression inversely correlated with the CD8+ tumor-infiltrating lymphocytes (TILs) content. In the 4T1 metastatic mouse model of TNBC, TSP1 silencing did not affect primary tumor development but, strikingly, impaired metastasis in immunocompetent but not in immunodeficient nude mice. Moreover, TSP1 knockdown increased tumor vascularization and T lymphocyte infiltration and decreased TGF-β activation in immunocompetent mice. Noteworthy was the finding that TSP1 knockdown increased CD8+ TILs and their programmed cell death 1 (PD-1) expression and sensitized 4T1 tumors to anti-PD-1 therapy. TSP1 inhibition might thus represent an innovative targeted approach to impair TGF-β activation and breast cancer cell metastasis and improve lymphocyte infiltration in tumors, and immunotherapy efficacy in TNBC.
Nanoparticles: Promising Auxiliary Agents for Diagnosis and Therapy of Thyroid Cancers
Authors: Fröhlich Eleonore , Wahl Richard
Published: August 2021

Cancers of the endocrine system are rare. The majority are not highly malignant tumors. Thyroid cancer (TC) is the most common endocrine cancer, with differentiated papillary and follicular tumors occurring more frequently than the more aggressive poorly differentiated and anaplastic TC. Nanoparticles (NP) (mainly mesoporous silica, gold, carbon, or liposomes) have been developed to improve the detection of biomarkers and routine laboratory parameters (e.g., thyroid stimulating hormone, thyroglobulin, and calcitonin), tumor imaging, and drug delivery in TC. The majority of drug-loaded nanocarriers to be used for treatment was developed for anaplastic tumors because current treatments are suboptimal. Further, doxorubicin, sorafenib, and gemcitabine treatment can be improved by nanotherapy due to decreased adverse effects. Selective delivery of retinoic acid to TC cells might improve the re-differentiation of de-differentiated TC. The use of carbon NPs for the prevention of parathyroid damage during TC surgery does not show a clear benefit. Certain technologies less suitable for the treatment of deeply located cancers may have some potential for unresectable anaplastic carcinomas, namely those based on low-intensity focused ultrasound and near-infrared irradiation. Although some of these approaches yielded promising results in animal studies, results from clinical trials are currently lacking.
3D Printing and Bioprinting to Model Bone Cancer: The Role of Materials and Nanoscale Cues in Directing Cell Behavior
Authors: Fischetti Tiziana , Di Pompo Gemma , Baldini Nicola , Avnet Sofia , Graziani Gabriela
Published: August 2021

Bone cancer, both primary and metastatic, is characterized by a low survival rate. Currently, available models lack in mimicking the complexity of bone, of cancer, and of their microenvironment, leading to poor predictivity. Three-dimensional technologies can help address this need, by developing predictive models that can recapitulate the conditions for cancer development and progression. Among the existing tools to obtain suitable 3D models of bone cancer, 3D printing and bioprinting appear very promising, as they enable combining cells, biomolecules, and biomaterials into organized and complex structures that can reproduce the main characteristic of bone. The challenge is to recapitulate a bone-like microenvironment for analysis of stromal–cancer cell interactions and biological mechanics leading to tumor progression. In this review, existing approaches to obtain in vitro 3D-printed and -bioprinted bone models are discussed, with a focus on the role of biomaterials selection in determining the behavior of the models and its degree of customization. To obtain a reliable 3D bone model, the evaluation of different polymeric matrices and the inclusion of ceramic fillers is of paramount importance, as they help reproduce the behavior of both normal and cancer cells in the bone microenvironment. Open challenges and future perspectives are discussed to solve existing shortcomings and to pave the way for potential development strategies.
Effects of Reaction Temperature on the Photocatalytic Activity of TiO2 with Pd and Cu Cocatalysts
Authors: Chen Yu-Wen , Hsu Yu-Hsuan
Published: August 2021

The aim of this study was to investigate the effects of reaction temperature on the photocatalytic activity of TiO2 with Pd and Cu cocatalysts. N2 sorption, transmission electron microscopy and high-resolution transmission electron microscopy were used to characterize the specific surface area, pore volume, pore size, morphology and metal distribution of the catalysts. The photocatalytic destruction of methylene blue under UV light irradiation was used to test its activity. The concentration of methylene blue in water was determined by UV-vis spectrophotometer. Pd/TiO2 catalyst was more active than Cu/TiO2 and TiO2. At 0–50 °C reaction temperature, the activity of TiO2 and Pd/TiO2 increased with an increase of reaction temperature. When the temperature was as high as 70 °C, the reaction rate of TiO2 drop slightly and Pd/TiO2 became less effective. In contrast, Cu/TiO2 was more active at room temperature than the other temperatures. The results indicate that the photocatalytic activity of the catalyst is influenced by the reaction temperature and the type of cocatalyst. When the reaction temperature is higher than 70 °C, the recombination of charge carriers will increase. The temperature range of 50–80 °C is regarded as the ideal temperature for effective photolysis of organic matter. The effects of reaction temperature mainly influence quantum effect, i.e., electron-hole separation and recombination.
Anti-Obesity Drug Orlistat Alleviates Western-Diet-Driven Colitis-Associated Colon Cancer via Inhibition of STAT3 and NF-κB-Mediated Signaling
Authors: Jin Bo-Ram , Kim Hyo-Jung , Sim Seo-Ah , Lee Minho , An Hyo-Jin
Published: August 2021

Many researchers have argued that Western diet (WD)-induced obesity accelerates inflammation and that inflammation is a link between obesity and colorectal cancer (CRC). This study investigated the effect of WDs on the development and progression of colitis-associated colon cancer (CAC) and the efficacy of the anti-obesity agent orlistat on WD-driven CAC in mice. The results revealed that the WD exacerbated CAC in azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced mice, which showed increased mortality, tumor formation, and aggravation of tumor progression. Furthermore, WD feeding also upregulated inflammation, hyperplasia, and tumorigenicity levels through the activation of STAT3 and NF-κB signaling in an AOM/DSS-induced mouse model. In contrast, treatment with orlistat increased the survival rate and alleviated the symptoms of CAC, including a recovery in colon length and tumor production decreases in WD-driven AOM/DSS-induced mice. Additionally, orlistat inhibited the extent of inflammation, hyperplasia, and tumor progression via the inhibition of STAT3 and NF-κB activation. Treatment with orlistat also suppressed the β-catenin, slug, XIAP, Cdk4, cyclin D, and Bcl-2 protein levels in WD-driven AOM/DSS-induced mice. The results of this study indicate that orlistat alleviates colon cancer promotion in WD-driven CAC mice by suppressing inflammation, especially by inhibiting STAT3 and NF-κB activation.
Myostatin/Activin-A Signaling in the Vessel Wall and Vascular Calcification
Authors: Esposito Pasquale , Verzola Daniela , Picciotto Daniela , Cipriani Leda , Viazzi Francesca , Garibotto Giacomo
Published: August 2021

A current hypothesis is that transforming growth factor-β signaling ligands, such as activin-A and myostatin, play a role in vascular damage in atherosclerosis and chronic kidney disease (CKD). Myostatin and activin-A bind with different affinity the activin receptors (type I or II), activating distinct intracellular signaling pathways and finally leading to modulation of gene expression. Myostatin and activin-A are expressed by different cell types and tissues, including muscle, kidney, reproductive system, immune cells, heart, and vessels, where they exert pleiotropic effects. In arterial vessels, experimental evidence indicates that myostatin may mostly promote vascular inflammation and premature aging, while activin-A is involved in the pathogenesis of vascular calcification and CKD-related mineral bone disorders. In this review, we discuss novel insights into the biology and physiology of the role played by myostatin and activin in the vascular wall, focusing on the experimental and clinical data, which suggest the involvement of these molecules in vascular remodeling and calcification processes. Moreover, we describe the strategies that have been used to modulate the activin downward signal. Understanding the role of myostatin/activin signaling in vascular disease and bone metabolism may provide novel therapeutic opportunities to improve the treatment of conditions still associated with high morbidity and mortality.
Epidermal Nevus Syndrome Associated with Dwarfism and Atopic Dermatitis
Authors: Mizutani Yuki , Nagai Miki , Iwata Hitoshi , Matsunami Kunihiro , Seishima Mariko
Published: August 2021

Epidermal nevus syndrome (ENS) is a congenital disorder characterized by widespread linear epidermal lesions consisting of epidermal nevus and extracutaneous involvements, especially of the central nervous system and skeletal system. Garcia–Hafner–Happle syndrome, also known as fibroblast growth factor receptor 3 (FGFR3)-ENS, is characterized by a systematized keratinocytic EN of soft and velvety type with neurological abnormalities such as seizures, intellectual impairment, and cortical atrophy. We present a case of a 9-year-old Japanese boy afflicted with Garcia–Hafner–Happle syndrome associated with dwarfism and atopic dermatitis. We show the results of physical examination, DNA analysis, and imaging studies and discuss the mutation underlying the child’s disorder.
Effects of CuO Sintering Aids on Microstructure and Electric Properties for (Na0.48K0.473Li0.04Sr0.007) (Nb0.883Ta0.05Sb0.06Ti0.007)O3 Ceramics
Authors: Hong Cheng-Shong , Zhang Yuan-Xin , Hong Yi-Tian
Published: August 2021

In this paper, the effects of CuO sintering aids on microstructure and electric properties are investigated for the non-stoichiometric (Na0.48K0.473Li0.04Sr0.007)(Nb0.883Ta0.05Sb0.06Ti0.007)O3+x mol% CuO lead free ceramics. As the amounts of CuO equal 1 mol%, the sintering temperature is 975 °C and the piezoelectric parameters are d33 = 200 pC/N, g33 = 38 (10−3 Vm/N), d33 × g33 = 7600 (10−15 m2/N), kp = 0.38, Qm = 240, Pr = 18.93 μC/cm2 and EC = 8.75 kV/cm. The piezoelectric properties are changed to hard type and suitable for energy harvester with multilayer technology. The physical response mechanisms are suggested that the diffused phase transitions are enhanced, the Cu2+ ions substitute for the B-site ions with forming the Oxygen vacancies and the domain walls are pinning.
RETRACTED: Preparation and Characterization of Mesoporous Silica from Bagasse Bottom Ash from the Sugar Industry
Authors: Amin Noorul , Gul Saeed , Sultana Sabiha , Alam Sultan
Published: August 2021

A novel and sustainable process to recycle an environmentally injurious material rich in silica—waste bagasse bottom ash from the sugar industry—into mesoporous pure silica of high purity is reported. Bagasse bottom ash (BBA) is a major byproduct of the sugar industry, with very inadequate recycling possibilities due to environmentally detrimental pollutants, whose production is dramatically increasing. In this study, for the first time, more than 70% of the silica from the bottom ash could be extracted for the synthesis of mesoporous silica using a low-temperature alkaline dissolution method instead of the customary elevated-temperature process. Furthermore, the process of dissolution was thoroughly studied to obtain the essential insight into silica hydrolysis that is largely missing from the existing research literature. Under alkaline conditions, the hydrolysis of silica is hindered due to the formation of zeolites and protective layers around the etching particles. This layer becomes a protective barrier that hinders the mass transfer of silica monomers to the solution, thus halting the dissolution process. Therefore, sequential extractions with optimized conditions of 100 °C for 72 h were employed to attain maximum silica extraction efficiency.
Resection of Non-Functional Pancreatic Neuroendocrine Neoplasms—A Single-Center Retrospective Outcome Analysis
Authors: Lindner Kirsten , Binte Daniel , Hoeppner Jens , Wellner Ulrich F. , Schulte Dominik M. , Schmid Sebastian M. , Luley Kim , Buchmann Inga , Tharun Lars , Keck Tobias , Gebauer Judith , Kulemann Birte
Published: August 2021

Surgery remains the only curative treatment of pancreatic neuroendocrine neoplasms (pNEN). Here, we report the outcome after surgery for non-functional pNEN at a European Neuroendocrine Tumor Society (ENETS) center in Germany between 2000 and 2019; cases were analyzed for surgical (Clavien–Dindo classification; CDc) and oncological outcomes. Forty-nine patients (tumor grading G1 n = 25, G2 n = 22, G3 n = 2), with a median age of 56 years, were included. Severe complications (CDc ≥ grade 3b) occurred in 11 patients (22.4%) and type B/C pancreatic fistulas (POPFs) occurred in 5 patients (10.2%); in-hospital mortality was 2% (n = 1). Six of seven patients with tumor recurrence (14.3%) had G2 tumors in the pancreatic body/tail. The median survival was 5.7 years (68 months; [1–228 months]). Neither the occurrence (p = 0.683) nor the severity of complications had an influence on the relapse behavior (p = 0.086). This also applied for a POPF (≥B, p = 0.609). G2 pNEN patients (n = 22) with and without tumor recurrence had similar median tumor sizes (4 cm and 3.9 cm, respectively). Five of the six relapsed G2 patients (83.3%) had tumor-positive lymph nodes (N+); all G2 pNEN patients with recurrence had initially been treated with distal pancreatic resection. Pancreatic resections for pNEN are safe but associated with relevant postoperative morbidity. Future studies are needed to evaluate suitable resection strategies for G2 pNEN.
Evaluating the Impact of the COVID-19 Pandemic on New Cancer Diagnoses and Oncology Care in Manitoba
Authors: Decker Kathleen M. , Lambert Pascal , Feely Allison , Bucher Oliver , Kim Julian O. , Hebbard Pamela , Thiessen Maclean , Fatoye Tunji , Pitz Marshall , Koul Rashmi , Czaykowski Piotr
Published: August 2021

Individuals with cancer are vulnerable to infection with SARS-CoV-2, the virus causing COVID-19. Physical distancing, the reallocation of health care resources, and the implementation of procedures to reduce the spread of COVID-19 may also have serious consequences for people with cancer. We evaluated the impact of COVID-19 on new cancer diagnoses and oncology care in Manitoba, Canada using an interrupted time series design and data from the Manitoba Cancer Registry and CancerCare Manitoba’s (CCMB) electronic medical record. In April 2020, there was a 23% decrease in new cancer diagnoses, a 21% decrease in pathology reports, and a 43% reduction in surgical resections. There was no difference in new cancer diagnoses by August 2020, surgery by July 2020, and pathology reports by September 2020. From April 2020 to June 2021, there was a 13% decrease in radiotherapy (RT) fractions, an 18% decrease in UCC visits, and a 52% decrease in in-person visits. There was no change in intravenous chemotherapy visits per month, first RT visits, or overall patient visits. The impact of COVID-19 on shifts in the stage at diagnosis and survival will be assessed in future analyses.
Interface of Human/Wildlife Interactions: An Example of a Bold Coyote (Canis latrans) in Atlanta, GA, USA
Authors: Mowry Christopher B. , Wilson Lawrence A. , vonHoldt Bridgett M.
Published: August 2021

There is arguably no other North American species that better illustrates the complexities of the human-wildlife interface than the coyote. In this study, a melanistic coyote in metropolitan Atlanta, Georgia was exhibiting unusually bold behaviors that included encounters with humans, domestic dogs, and attempts to enter homes. After tracking this coyote (nicknamed Carmine) across a highly urbanized landscape with participatory science, including at least 80 publicly reported sightings, he was captured and relocated to a wildlife sanctuary. Genome-wide analyses revealed 92.8% coyote ancestry, 1.7% gray wolf ancestry, and 5.5% domestic dog ancestry. The dog alleles in Carmine’s genome were estimated to have been acquired by his ancestors 14–29 years ago. Despite his bold behavior, Carmine did not carry any mutations known to shape hypersociability in canines. He did, however, carry a single copy of the dominant mutation responsible for his melanistic coat color. This detailed study of Carmine dispels common assumptions about the reticent coyote personality and the origins of behavior. His unusual bold behavior created a higher level of human-coyote interaction. He now serves as a public ambassador for human-wildlife coexistence, urging the global community to reconsider mythologies about wildlife and promote coexistence with them in landscapes significantly altered by human activity in our rapidly changing world.
A Current Review of the Etiology, Clinical Features, and Diagnosis of Urinary Tract Infection in Renal Transplant Patients
Authors: Suárez Fernández María Luisa , Ridao Cano Natalia , Álvarez Santamarta Lucia , Gago Fraile María , Blake Olivia , Díaz Corte Carmen
Published: August 2021

Urinary tract infection (UTI) represents the most common infection after kidney transplantation and remains a major cause of morbidity and mortality in kidney transplant (KT) recipients, with a potential impact on graft survival. UTIs after KT are usually caused by Gram-negative microorganisms. Other pathogens which are uncommon in the general population should be considered in KT patients, especially BK virus since an early diagnosis is necessary to improve the prognosis. UTIs following kidney transplantation are classified into acute simple cystitis, acute pyelonephritis/complicated UTI, and recurrent UTI, due to their different clinical presentation, prognosis, and management. Asymptomatic bacteriuria (ASB) represents a frequent finding after kidney transplantation, but ASB is considered to be a separate entity apart from UTI since it is not necessarily a disease state. In fact, current guidelines do not recommend routine screening and treatment of ASB in KT patients, since a beneficial effect has not been shown. Harmful effects such as the development of multidrug-resistant (MDR) bacteria and a higher incidence of Clostridium difficile diarrhea have been associated with the antibiotic treatment of ASB.
Diagnostic Performance of Three-Phase Bone Scintigraphy and Digital Infrared Thermography Imaging for Chronic Post-Traumatic Complex Regional Pain Syndrome
Authors: Cheon Miju , Kang Hyo Jung , Do Kyung Hee , Yang Hee Seung , Han Eul Joo , Yoo Jang
Published: August 2021

This study aimed to evaluate the diagnostic performance of three-phase bone scintigraphy (TPBS) and digital infrared thermography imaging (DITI) in the chronic post-traumatic CRPS and propose new imaging diagnostic criteria that combine the two tests. We retrospectively enrolled 44 patients with suspected symptoms of CRPS from various injuries during obligatory military service. We analyzed the following findings: (1) uptake pattern on TPBS, (2) uptake ratios of affected and unaffected sides in each phase of TPBS, (3) difference in body skin temperature on DITI. New criteria combining the above findings were also evaluated. Eighteen patients were finally defined as CRPS according to the Budapest criteria. Uptake pattern and uptake ratio in blood pool phase on the TPBS were significantly different between CRPS and non-CRPS groups (both p < 0.05). The DITI could not discriminate significantly between the groups (p = 0.334). The diagnostic criteria considering both the pattern analysis and quantitative analysis in TPBS exhibited the highest positive likelihood ratio. On the other hand, the diagnostic criteria combining DITI and TPBS showed the lowest negative likelihood ratio value. TPBS can be useful in diagnosing chronic post-traumatic CRPS. Moreover, we can suggest that different diagnostic criteria be applied depending on the purpose.
External Stimuli on Neural Networks: Analytical and Numerical Approaches
Authors: Curado Evaldo M. F. , Melgar Nilo B. , Nobre Fernando D.
Published: August 2021

Based on the behavior of living beings, which react mostly to external stimuli, we introduce a neural-network model that uses external patterns as a fundamental tool for the process of recognition. In this proposal, external stimuli appear as an additional field, and basins of attraction, representing memories, arise in accordance with this new field. This is in contrast to the more-common attractor neural networks, where memories are attractors inside well-defined basins of attraction. We show that this procedure considerably increases the storage capabilities of the neural network; this property is illustrated by the standard Hopfield model, which reveals that the recognition capacity of our model may be enlarged, typically, by a factor 102. The primary challenge here consists in calibrating the influence of the external stimulus, in order to attenuate the noise generated by memories that are not correlated with the external pattern. The system is analyzed primarily through numerical simulations. However, since there is the possibility of performing analytical calculations for the Hopfield model, the agreement between these two approaches can be tested—matching results are indicated in some cases. We also show that the present proposal exhibits a crucial attribute of living beings, which concerns their ability to react promptly to changes in the external environment. Additionally, we illustrate that this new approach may significantly enlarge the recognition capacity of neural networks in various situations; with correlated and non-correlated memories, as well as diluted, symmetric, or asymmetric interactions (synapses). This demonstrates that it can be implemented easily on a wide diversity of models.
Decoherence, Anti-Decoherence, and Fisher Information
Authors: Kowalski Andres M. , Plastino Angelo
Published: August 2021

In this work, we study quantum decoherence as reflected by the dynamics of a system that accounts for the interaction between matter and a given field. The process is described by an important information geometry tool: Fisher’s information measure (FIM). We find that it appropriately describes this concept, detecting salient details of the quantum–classical changeover (qcc). A good description of the qcc report can thus be obtained; in particular, a clear insight into the role that the uncertainty principle (UP) plays in the pertinent proceedings is presented. Plotting FIM versus a system’s motion invariant related to the UP, one can also visualize how anti-decoherence takes place, as opposed to the decoherence process studied in dozens of papers. In Fisher terms, the qcc can be seen as an order (quantum)–disorder (classical, including chaos) transition.
Frequency Domain Repercussions of Instantaneous Granger Causality
Authors: Baccalá Luiz A. , Sameshima Koichi
Published: August 2021

Using directed transfer function (DTF) and partial directed coherence (PDC) in the information version, this paper extends the theoretical framework to incorporate the instantaneous Granger causality (iGC) frequency domain description into a single unified perspective. We show that standard vector autoregressive models allow portraying iGC’s repercussions associated with Granger connectivity, where interactions mediated without delay between time series can be easily detected.
Identifying Students at Risk to Academic Dropout in Higher Education
Authors: Gallego María Gómez , Perez de los Cobos Alfonso Palazón , Gallego Juan Cándido Gómez
Published: August 2021

A main goal of the university institution should be to reduce the desertion of its students, in fact, the dropout rate constitutes a basic indicator in the accreditation processes of university centers. Thus, evaluating the cognitive functions and learning skills of students with an increased risk of academic failure can be useful for the adoption of strategies for preventing and reducing school dropout. In this research, cognitive functions and learning skills in 284 university students were evaluated. Academic performance predictors were identified, and conglomerates analysis was carried out to establish groups according to those variables. The stability and validity of the conglomerates were tested with discriminant analyzes and comparison tests. The variables associated significantly to academic performance were: attention, intelligence, motivation, metacognition and affective components. The conglomerate analysis suggested a three-group solution: (1) students with cognitive skills of moderate to high, but deficient learning strategies; (2) students with cognitive and learning capabilities of moderate to high; (3) students with cognitive functions low and moderate learning capacity. Students from groups 1 and 3 showed worse academic performance; 83.3% of students at risk of desertion belonged to such groups. Two groups of students have been identified with the highest risk of academic failure: those with poor cognitive capacity and those with bad learning skills.
The Application of X-rays for an Electrodeposition of Composite Coatings with Modified Structures and Properties
Authors: Valko Natalia , Evstigneeva Wiktoria , Anishchik Victor , Bondariev Vitalii , Okal Pawel , Koltunowicz Tomasz N.
Published: August 2021

Experimental studies of the effect of X-rays on the process of electrolytic deposition of composite coatings are reviewed in this paper. Particular emphasis will be on the applications of X-rays for both the modification of a structure and the mechanical characteristics of galvanic coatings. In particular, this research investigates the Co/SiO2 coatings deposited from aqueous solutions under the effect of X-rays. The results of extensive investigations into the dispersing ability of electrolytes with SiO2 nanoparticles and a mass rate of composite coatings Co/SiO2 indicates that the method of electroplating under the effect of X-rays during the process results in the intensification of diffusion in the electrolyte volume and creates dense, uniform coatings. This research demonstrates that exposure of an electrolytic cell to X-rays during the electroplating process of Co/SiO2 results in an orienting effect on the formation of crystal grains and allows for the creation of dense, morphology uniform coatings with increased hardness and improved adhesion.
Assessing the Energy, Indoor Air Quality, and Moisture Performance for a Three-Story Building Using an Integrated Model, Part Two: Integrating the Indoor Air Quality, Moisture, and Thermal Comfort
Authors: Heibati Seyedmohammadreza , Maref Wahid , Saber Hamed H.
Published: August 2021

In this paper, an integrated model that coupled CONTAM and WUFI was developed to assess the indoor air quality (IAQ), moisture, and thermal comfort performance. The coupling method of CONTAM and WUFI is described based on the exchange of airflow rate control variables as infiltration, natural and mechanical ventilation parameters between heat and moisture flow balance equations in WUFI and contaminant flow balances equations in CONTAM. To evaluate the predictions of the integrated model compared to single models of CONTAM and WUFI, four scenarios were used. These scenarios are airtight-fan off, airtight-fan on, leaky-fan off, and leaky-fan on, and were defined for a three-story house subjected to three different climate conditions of Montreal, Vancouver, and Miami. The measures of the simulated indoor CO2, PM2.5, and VOCs obtained by CONTAM; the simulated indoor relative humidity (RH), predicted percentage of dissatisfied (PPD), and predicted mean vote (PMV) obtained by WUFI; and those obtained by the integrated model are compared separately for all scenarios in Montreal, Vancouver, and Miami. Finally, the optimal scenarios are selected. The simulated results of the optimal scenarios with the integrated model method (−28.88% to 46.39%) are different from those obtained with the single models. This is due to the inability of the single models to correct the airflow variables.
Design Consideration of Bidirectional Wireless Power Transfer and Full-Duplex Communication System via a Shared Inductive Channel
Authors: Wu Jie , Kong Weihao , Gao Pengfei , Jin Nan , Zhang Jitao , Tao Jiagui , Snášel Václav
Published: August 2021

Communication between the primary and secondary sides is pivotal to the wireless power transfer (WPT) system. The system control commands and feedback information need simultaneous wireless information and power transfer (SWIPT). In this paper, a FSK-based SWIPT system with full-duplex communication via a shared channel is provided. Considering the complexity of the coupling relationship in this kind of full-duplex SWIPT system, this paper proposes an analysis method based on the transmission channel, studies the crosstalk between the power channel and the information channel, and between the forward and reverse transfer of information. A design method of full-duplex communication SWIPT system based on shared coupling channels is provided. A 60 W SWIPT prototype with a full-duplex communication rate of 20 kbps is built to verify the proposed method.
Including Heat Balance When Designing the Energy System of Fuel Cell-Powered AUVs
Authors: Chiche Ariel , Lindbergh Göran , Stenius Ivan , Lagergren Carina
Published: August 2021

Fuel cell-powered Autonomous Underwater Vehicles (AUVs) represent a growing area of research as fuel cells can increase their endurance. Fuel cells consume hydrogen and oxygen to generate electricity. Typically, the fuel cell generates as much heat as electrical energy, and heat management becomes a crucial parameter when designing AUVs. For underwater applications, there is a need to store both gases and several types of storage units with different characteristics exist which have impacts on the energy density and heat behavior. This study aims at including the heat properties of the storage units in the design process of fuel cell-powered AUVs. A heat balance over the energy system of an AUV is calculated for each combination of hydrogen and oxygen storage units. In addition, a multi-criteria decision-making analysis is conducted, considering the calculated total heat, the specific energy, the energy density and the volumetric mass of each combination of storage units as criteria, enabling a comparison and ranking them using two objective criteria weighting methods. Results show that the fuel cell is the major contributor to the heat balance, and that the combinations of liquid oxygen with liquid or compressed hydrogen can be relevant and suitable for underwater applications.
Effect of Rice Husk Filler on the Structural and Dielectric Properties of Palm Oil as an Electrical Insulation Material
Authors: Junian Siti Sarah , Makmud Mohamad Zul Hilmey , Jamain Zuhair , Mohd Amin Khairatun Najwa , Dayou Jedol , Azil Illias Hazlee
Published: August 2021

This study uses natural fibre, which is moisture absorbent, as an innovative and economical filler for insulating oil. Rice husk (RH) is a natural fibre known to have water-absorbing properties and used as a supplementary cementitious material. This research utilises the water-absorbing properties of RH to improve the physicochemical and dielectric properties of insulating oil. RH was refined into a fine powder at a diameter of less than 63 µm. Palm oil (PO) was synthesised with RH at concentrations of 0 g/L, 0.01 g/L, and 0.1 g/L. The moisture-absorbent properties of RH were analysed by using Fourier-transform infrared (FTIR) spectroscopy. The particle size and distribution of RH in PO were also obtained using a scanning electron microscope (SEM) and a Zeta particle analyser. The breakdown voltage (BDV) strength of PO with RH was measured according to IEC 60156, and the dielectric frequency response was investigated in the range of 102–105 Hz. RH is proven to absorb moisture from PO, as the O–H band intensity at the 3350 cm−1 is increased from the experimental results. Therefore, the mean BDV and dielectric insulation properties of PO dispersed with RH also increased accordingly.
Condition Monitoring of Internal Combustion Engines in Thermal Power Plants Based on Control Charts and Adapted Nelson Rules
Authors: Vilas Boas Fernanda Mitchelly , Borges-da-Silva Luiz Eduardo , Villa-Nova Helcio Francisco , Bonaldi Erik Leandro , Oliveira Levy Ely Lacerda , Lambert-Torres Germano , Assuncao Frederico de Oliveira , Costa Claudio Inacio de Almeida , Campos Mateus Mendes , Sant’Ana Wilson Cesar , Lacerda Josue , da Silva Junior Jose Luiz Marques , da Silva Edenio Gomes
Published: August 2021

In thermal power plants, the internal combustion engines are constantly subjected to stresses, requiring a continuous monitoring system in order to check their operating conditions. However, most of the time, these monitoring systems only indicate if the monitored parameters are in nonconformity close to the occurrence of a catastrophic failure—they do not allow a predictive analysis of the operating conditions of the machine. In this paper, a statistical model, based on the statistical control process and Nelson Rules, is proposed to analyze the operational conditions of the machine based on the supervisory system data. The statistical model is validated through comparisons with entries of the plant logbook. It is demonstrated that the results obtained with the proposed statistical model match perfectly with the entries of the logbook, showing our model to be a promising tool for making decisions concerning maintenance in the plant.
Facile Synthesis of Coral Reef-Like ZnO/CoS2 Nanostructure on Nickel Foam as an Advanced Electrode Material for High-Performance Supercapacitors
Authors: Durga Ikkurthi Kanaka , Raghavendra Kummara Venkata Guru , Kundakarla Naga Bhushanam , Alapati Suresh , Ahn Jin-Woo , Srinivasa Rao Sunkara
Published: August 2021

Nanocomposite electrodes receive much attention because of their excellent energy storage nature. Electrodes for supercapacitors have come a major source of interest. In this pursuit, the current work elucidates binder-free coral reefs resembling ZnO/CoS2 nanoarchitectures synthesized on the surface of Ni foams employing the cost-effective hydrothermal route. The Zno/CoS2 nanocomposite demonstrated excellent battery-type behavior, which can be employed for supercapcitor application. Various analyses were carried out in the current study, such as X-ray diffraction and high-resolution scanning electron microscopy, which allowed defining the crystalline nature and morphology of surface with ZnO/CoS2 nanoarchitectures. Electrochemical measures such as cyclic voltammetry, galvanostatic charge discharge, and potentiostatic impedance spectroscopy confirmed the battery-type behavior of the material. The synthesized precursors of binder-free ZnO/CoS2 nanostructures depicted an excellent specific capacity of 400.25 C·g−1 at 1 A·g−1, with a predominant cycling capacity of 88. 2% and retention holding of 68% at 10 A·g−1 and 2 A·g−1, even after 4000 cycles, representing an improvement compared to the pristine ZnO and CoS2 electroactive materials. Therefore, the electrochemical and morphological analyses suggest the excellent behavior of the ZnO/CoS2 nanoarchitectures, making them promising for supercapacitors.
Optimization of the Beef Drying Process in a Heat Pump Chamber Dryer
Authors: Olejnik Tomasz P. , Mysakowski Tymoteusz , Tomtas Paweł , Mostowski Radosław
Published: August 2021

Uneven air distribution in chamber dryers is a common and serious technological challenge. A study using CFD (Computer Fluid Dynamics) simulation, supported by measurements in a heat pump chamber dryer, confirmed irregular airflows. Performing simulations with modified settings and additional chamber modifications enabled the airflows to be visualized and optimized. It was shown that a modification of the chamber where a rotating disc had been used had a positive effect on the uniform distribution of air flows in the drying chamber. The modification significantly improves the energy balance of the beef drying process. Optimization of the process resulted in obtaining a high quality final product-beef jerky. This investigation proves that appropriate drying process control and introduced modifications enable high product quality and a safe level of water activity without the preservatives supplementation.
Review of Energy Storage and Energy Management System Control Strategies in Microgrids
Authors: Chaudhary Gaurav , Lamb Jacob J. , Burheim Odne S. , Austbø Bjørn
Published: August 2021

A microgrid (MG) is a discrete energy system consisting of an interconnection of distributed energy sources and loads capable of operating in parallel with or independently from the main power grid. The microgrid concept integrated with renewable energy generation and energy storage systems has gained significant interest recently, triggered by increasing demand for clean, efficient, secure, reliable and sustainable heat and electricity. However, the concept of efficient integration of energy storage systems faces many challenges (e.g., charging, discharging, safety, size, cost, reliability and overall management). Additionally, proper implementation and justification of these technologies in MGs cannot be done without energy management systems, which control various aspects of power management and operation of energy storage systems in microgrids. This review discusses different energy storage technologies that can have high penetration and integration in microgrids. Moreover, their working operations and characteristics are discussed. An overview of the controls of energy management systems for microgrids with distributed energy storage systems is also included in the scope of this review.
A Novel Driving Scheme for Three-Phase Bearingless Induction Machine with Split Winding
Authors: Carvalho Souza Francisco Elvis , Silva Werbet , Ortiz Salazar Andrés , Paiva José , Moura Diego , Villarreal Elmer Rolando Llanos
Published: August 2021

In order to reduce the costs of implementing the radial position control system of a three-phase bearingless machine with split winding, this article proposes a driving method that uses only two phases of the system instead of the three-phase traditional one. It reduces from six to four the number of inverter legs, drivers, sensors, and current controllers necessary to drive and control the system. To justify the proposal, this new power and control configuration was applied to a 250 W machine controlled by a digital signal processor (DSP). The results obtained demonstrated that it is possible to carry out the radial position control through two phases, without loss of performance in relation to the conventional three-phase drive and control system.
Optimal Daily Trading of Battery Operations Using Arbitrage Spreads
Authors: Abramova Ekaterina , Bunn Derek
Published: August 2021

An important revenue stream for electric battery operators is often arbitraging the hourly price spreads in the day-ahead auction. The optimal approach to this is challenging if risk is a consideration as this requires the estimation of density functions. Since the hourly prices are not normal and not independent, creating spread densities from the difference of separately estimated price densities is generally intractable. Thus, forecasts of all intraday hourly spreads were directly specified as an upper triangular matrix containing densities. The model was a flexible four-parameter distribution used to produce dynamic parameter estimates conditional upon exogenous factors, most importantly wind, solar and the day-ahead demand forecasts. These forecasts supported the optimal daily scheduling of a storage facility, operating on single and multiple cycles per day. The optimization is innovative in its use of spread trades rather than hourly prices, which this paper argues, is more attractive in reducing risk. In contrast to the conventional approach of trading the daily peak and trough, multiple trades are found to be profitable and opportunistic depending upon the weather forecasts.
RETRACTED: Gładyszewska-Fiedoruk et al. Simulation and Analysis of Various Ventilation Systems Given in an Example in the Same School of Indoor Air Quality. Energies 2019, 12, 2845
Authors:   Energies Editorial Office
Published: August 2021

The journal retracts the above cited article, Simulation and Analysis of Various Ventilation Systems Given in an Example in the Same School of Indoor Air Quality [...]
Optimal Sizing of Electric Vehicle Charging Stations Considering Urban Traffic Flow for Smart Cities
Authors: Campaña Miguel , Inga Esteban , Cárdenas Jorge
Published: August 2021

Achieving high penetration of electric vehicles (EVs) is one of the objectives proposed by the scientific community to mitigate the negative environmental impact caused by conventional mobility. The limited autonomy and the excessive time to recharge the battery discourage the final consumer from opting for new environmentally friendly mobility alternatives. Consequently, it is essential to provide the urban road network with charging infrastructure (CI) to ensure that the demand generated by EV users is met. The types of terminals to be considered in charging stations (CS) are fast and ultra-fast. The high energy requirements in these types of terminals could stress the electrical systems, reducing the quality of service. To size and forecast the resources needed in CI, it is of great interest to model and predict the maximum number of EVs, in each hour, that each CS will have to serve according to the geographic area in which they are located. Our proposal is not based on an assumed number of vehicles to be served by each CS, but rather it is based on the analysis of vehicular traffic in geo-referenced areas, so that the load managers can design the topology of the CS. The maximum vehicular concentration is determined by some considerations such as the road system, direction of the route, length of the road segment, the intersections, and the economic zone to which it belongs. The topology of the road map is freely extracted from OpenStreetMap to know the latitude and longitude coordinates. Vehicular traffic will be modeled through the topology obtained from OpenStreetMap and other microscopic variables to understand the traffic engineering constraints. In addition, the Hungarian algorithm is used as a minimum cost decision tool to allocate demand to the CS by observing vehicular traffic as a cost variable. The multi commodity flow problem (MCFP) algorithm aims to make commodities flow through the road network with the minimum cost without exceeding the capacities of the road sections. Therefore, it is proposed to solve the transportation problem by directing the vehicular flow to the CS while minimizing the travel time. This situation will contribute significantly to the design of the topology of each CS, which will be studied in future research.