bluuebunny/crossref_metadata_2025 huggingface dataset:
Ultra-Deep Oxidative Desulfurization of Fuel with H2O2 Catalyzed by Mesoporous Silica-Supported Molybdenum Oxide Modified by Ce
Authors: Chen Yang , Tian Qi , Tian Yongsheng , Cui Jiawei , Wang Guanghui
Published: February 2021

A mesoporous silica-supported molybdenum oxide catalyst with a cerium(Ce) modifier was prepared by in situ synthesis and used in a hydrogen peroxide (H2O2) system for the desulfurization of dibenzothiophene (DBT), benzothiophene (BT), and 4,6-dimethyldibenzothiophene (4,6-DMDBT) fuel oils. The catalytic performance of the catalyst was studied. The catalyst was characterized by Fourier Transform Infra-Red (FT-IR), X-ray diffraction (XRD), Brunner−Emmet−Teller (BET), and X-ray Photoelectron Spectroscopy (XPS). The influences of m(catalyst)/m(fuel oil), v(H2O2)/v(fuel oil), reaction temperature, and reaction time were investigated. The catalyst had excellent catalytic oxidation desulfurization performance under moderate operational conditions. The catalytic performance was in the order DBT > 4,6-DMDBT > BT. The kinetic analysis results showed that the reaction was a pseudo first-order kinetics process and the apparent activation energies of DBT, BT, and 4,6-DMDBT were 46.67 kJ/mol, 56.23 kJ/mol, and 55.54 kJ/mol, respectively. The reaction products of DBT, BT, and 4,6-DMDBT were DBTO2, BTO2, and 4,6-DMDBTO2, respectively. The recycling experiments indicated that DBT, BT, and 4,6-DMDBT removal could still reach levels of 94.0%, 63.0%, and 77.9% after five cycles.
Heatwaves and Summer Urban Heat Islands: A Daily Cycle Approach to Unveil the Urban Thermal Signal Changes in Lisbon, Portugal
Authors: Oliveira Ana , Lopes António , Correia Ezequiel , Niza Samuel , Soares Amílcar
Published: February 2021

Lisbon is a European Mediterranean city, greatly exposed to heatwaves (HW), according to recent trends and climate change prospects. Considering the Atlantic influence, air temperature observations from Lisbon’s mesoscale network are used to investigate the interactions between background weather and the urban thermal signal (UTS) in summer. Days are classified according to the prevailing regional wind direction, and hourly UTS is compared between HW and non-HW conditions. Northern-wind days predominate, revealing greater maximum air temperatures (up to 40 °C) and greater thermal amplitudes (approximately 10 °C), and account for 37 out of 49 HW days; southern-wind days have milder temperatures, and no HWs occur. Results show that the wind direction groups are significantly different. While southern-wind days have minor UTS variations, northern-wind days have a consistent UTS daily cycle: a diurnal urban cooling island (UCI) (often lower than –1.0 °C), a late afternoon peak urban heat island (UHI) (occasionally surpassing 4.0 °C), and a stable nocturnal UHI (1.5 °C median intensity). UHI/UCI intensities are not significantly different between HW and non-HW conditions, although the synoptic influence is noted. Results indicate that, in Lisbon, the UHI intensity does not increase during HW events, although it is significantly affected by wind. As such, local climate change adaptation strategies must be based on scenarios that account for the synergies between potential changes in regional air temperature and wind.
Quantum Simulation of the Silicene and Germanene for Sensing and Sequencing of DNA/RNA Nucleobases
Authors: Gürel Hikmet Hakan , Salmankurt Bahadır
Published: February 2021

Over the last decade, we have been witnessing the rise of two-dimensional (2D) materials. Several 2D materials with outstanding properties have been theoretically predicted and experimentally synthesized. 2D materials are good candidates for sensing and detecting various biomolecules because of their extraordinary properties, such as a high surface-to-volume ratio. Silicene and germanene are the monolayer honeycomb structures of silicon and germanium, respectively. Quantum simulations have been very effective in understanding the interaction mechanism of 2D materials and biomolecules and may play an important role in the development of effective and reliable biosensors. This article focuses on understanding the interaction of DNA/RNA nucleobases with silicene and germanane monolayers and obtaining the possibility of using silicene and germanane monolayers as a biosensor for DNA/RNA nucleobases’ sequencing using the first principle of Density Functional Theory (DFT) calculations with van der Waals (vdW) correction and nonequilibrium Green’s function method. Guanine (G), Cytosine (C), Adenine (A), Thymine (T), and Uracil (U) were examined as the analytes. The strength of adsorption between the DNA/RNA nucleobases and silicene and germanane is G > C > A > T > U. Moreover, our recent work on the investigation of Au- and Li-decorated silicene and germanane for detection of DNA/RNA nucleobases is presented. Our results show that it is possible to get remarkable changes in transmittance due to the adsorption of nucleobases, especially for G, A, and C. These results indicate that silicene and germanene are both good candidates for the applications in fast sequencing devices for DNA/RNA nucleobases. Additionally, our present results have the potential to give insight into experimental studies and can be valuable for advancements in biosensing and nanobiotechnology.
Unexpected Benefits of Multiport Synchrotron Microbeam Radiation Therapy for Brain Tumors
Authors: Eling Laura , Bouchet Audrey , Ocadiz Alexandre , Adam Jean-François , Kershmiri Sarvenaz , Elleaume Hélène , Krisch Michael , Verry Camille , Laissue Jean A. , Balosso Jacques , Serduc Raphaël
Published: February 2021

Delivery of high-radiation doses to brain tumors via multiple arrays of synchrotron X-ray microbeams permits huge therapeutic advantages. Brain tumor (9LGS)-bearing and normal rats were irradiated using a conventional, homogeneous Broad Beam (BB), or Microbeam Radiation Therapy (MRT), then studied by behavioral tests, MRI, and histopathology. A valley dose of 10 Gy deposited between microbeams, delivered by a single port, improved tumor control and median survival time of tumor-bearing rats better than a BB isodose. An increased number of ports and an accumulated valley dose maintained at 10 Gy delayed tumor growth and improved survival. Histopathologically, cell death, vascular damage, and inflammatory response increased in tumors. At identical valley isodose, each additional MRT port extended survival, resulting in an exponential correlation between port numbers and animal lifespan (r2 = 0.9928). A 10 Gy valley dose, in MRT mode, delivered through 5 ports, achieved the same survival as a 25 Gy BB irradiation because of tumor dose hot spots created by intersecting microbeams. Conversely, normal tissue damage remained minimal in all the single converging extratumoral arrays. Multiport MRT reached exceptional ~2.5-fold biological equivalent tumor doses. The unique normal tissue sparing and therapeutic index are eminent prerequisites for clinical translation.
RETRACTED: MicroRNA-21 Plays Multiple Oncometabolic Roles in the Process of NAFLD-Related Hepatocellular Carcinoma via PI3K/AKT, TGF-β, and STAT3 Signaling
Authors: Lai Chi-Yu , Yeh Kun-Yun , Lin Chiu-Ya , Hsieh Yang-Wen , Lai Hsin-Hung , Chen Jim-Ray , Hsu Chia-Chun , Her Guor
Published: February 2021

MicroRNA-21 (miR-21) is one of the most frequently upregulated miRNAs in liver diseases such as nonalcoholic fatty liver disease (NAFLD) and hepatocellular carcinoma (HCC). However, mechanistic pathways that connect NAFLD and HCC remain elusive. We developed a doxycycline (Dox)-inducible transgenic zebrafish model (LmiR21) which exhibited an upregulation of miR-21 in the liver, which in turn induced the full spectrum of NAFLD, including steatosis, inflammation, fibrosis, and HCC, in the LmiR21 fish. Diethylnitrosamine (DEN) treatment led to accelerated liver tumor formation and exacerbated their aggressiveness. Moreover, prolonged miR-21 expression for up to ten months induced nonalcoholic steatohepatitis (NASH)-related HCC (NAHCC). Immunoblotting and immunostaining confirmed the presence of miR-21 regulatory proteins (i.e., PTEN, SMAD7, p-AKT, p-SMAD3, and p-STAT3) in human nonviral HCC tissues and LmiR21 models. Thus, we demonstrated that miR-21 can induce NAHCC via at least three mechanisms: First, the occurrence of hepatic steatosis increases with the decrease of ptenb, pparaa, and activation of the PI3K/AKT pathway; second, miR-21 induces hepatic inflammation (or NASH) through an increase in inflammatory gene expression via STAT3 signaling pathways, and induces liver fibrosis through hepatic stellate cell (HSC) activation and collagen deposition via TGF-β/Smad3/Smad7 signaling pathways; finally, oncogenic activation of Smad3/Stat3 signaling pathways induces HCC. Our LmiR21 models showed similar molecular pathology to the human cancer samples in terms of initiation of lipid metabolism disorder, inflammation, fibrosis and activation of the PI3K/AKT, TGF-β/SMADs and STAT3 (PTS) oncogenic signaling pathways. Our findings indicate that miR-21 plays critical roles in the mechanistic perspectives of NAHCC development via the PTS signaling networks.
Blocking Aerobic Glycolysis by Targeting Pyruvate Dehydrogenase Kinase in Combination with EGFR TKI and Ionizing Radiation Increases Therapeutic Effect in Non-Small Cell Lung Cancer Cells
Authors: Dyrstad Sissel E. , Lotsberg Maria L. , Tan Tuan Zea , Pettersen Ina K. N. , Hjellbrekke Silje , Tusubira Deusdedit , Engelsen Agnete S. T. , Daubon Thomas , Mourier Arnaud , Thiery Jean Paul , Dahl Olav , Lorens James B. , Tronstad Karl Johan , Røsland Gro V.
Published: February 2021

Increased glycolytic activity is a hallmark of cancer initiation and progression and is often observed in non-small cell lung cancer (NSCLC). Pyruvate dehydrogenase (PDH) complex acts as a gatekeeper between glycolysis and oxidative phosphorylation, and activation of PDH is known to inhibit glycolytic activity. As part of a standard therapeutic regimen, patients with NSCLC harboring oncogenic mutations in the epidermal growth factor receptor (EGFR) are treated with EGFR tyrosine kinase inhibitors (EGFR TKIs). Independent of good initial response, development of resistance to this therapy is inevitable. In the presented work, we propose that inhibition of glycolysis will add to the therapeutic effects and possibly prevent development of resistance against both EGFR TKIs and ionizing radiation in NSCLC. Analysis of transcriptome data from two independent NSCLC patient cohorts identified increased expression of pyruvate dehydrogenase kinase 1 (PDHK1) as well as upregulated expression of genes involved in glucose metabolism in tumors compared to normal tissue. We established in vitro models of development of resistance to EGFR TKIs to study metabolism and determine if targeting PDHK would prevent development of resistance to EGFR TKIs in NSCLC cells. The PDHK1 inhibitor dichloroacetate (DCA) in combination with EGFR TKIs and/or ionizing radiation was shown to increase the therapeutic effect in our NSCLC cell models. This mechanism was associated with redirected metabolism towards pyruvate oxidation and reduced lactate production, both in EGFR TKI sensitive and resistant NSCLC cells. Using DCA, the intracellular pool of pyruvate available for lactic fermentation becomes limited. Consequently, pyruvate is redirected to the mitochondria, and reinforces mitochondrial activity. Addition of DCA to cell culture deacidifies the extracellular microenvironment as less lactate is produced and excreted. In our study, we find that this redirection of metabolism adds to the therapeutic effect of EGFR TKI and ionizing radiation in NSCLC.
What Is on Your Mind? Impaired Social Cognition in Primary Central Nervous System Lymphoma Patients Despite Ongoing Complete Remission
Authors: Pertz Milena , Kowalski Thomas , Thoma Patrizia , Schlegel Uwe
Published: February 2021

Within the past decades, long-term survival was achieved in a substantial fraction of primary central nervous system lymphoma (PCNSL) patients, expanding the focus of research to their quality of life (QoL). Social relationships crucially contribute to well-being in the context of adversity. Therefore, abilities that facilitate social interactions essentially determine QoL. The present study specifically targeted those sociocognitive abilities. Forty-three PCNSL patients with ongoing complete remission to therapy for at least one year and 43 healthy controls matched for age, gender and education were examined with standardized self-report and behavioral measures of social cognition. An impaired ability to comprehend others’ feelings was found in patients for both positive and negative mental states. Patients had difficulties in identifying the awkward element in challenging social situations, whereas the degree of discomfort experienced in those situations was comparable between groups. Both the production of optimal solutions for social situations and the mere recognition of these among less optimal strategies were impaired in patients. Clinicians should be aware of possible sociocognitive impairment and ought to address this in additional supportive interventions. Impaired sociocognitive abilities may entail social conflicts at a time when patients rely on social support. This, in turn, could detrimentally affect QoL.
Modification of Homologous Recombination Deficiency Score Threshold and Association with Long-Term Survival in Epithelial Ovarian Cancer
Authors: How Jeffrey A. , Jazaeri Amir A. , Fellman Bryan , Daniels Molly S. , Penn Suzanna , Solimeno Cara , Yuan Ying , Schmeler Kathleen , Lanchbury Jerry S. , Timms Kirsten , Lu Karen H. , Yates Melinda S.
Published: February 2021

New therapies, such as poly-ADP ribose polymerase inhibitors (PARPi), and immunotherapy treatments have generated great interest in enhancing individualized molecular profiling of epithelial ovarian cancer (EOC) to improve management of the disease. In EOC patients, putative biomarkers for homologous recombination deficiency (HRD), microsatellite instability (MSI), and tumor mutational burden (TMB) were characterized and correlated with survival outcomes. A series of 300 consecutive EOC patients were enrolled. Patients underwent neoadjuvant chemotherapy (n = 172) or primary cytoreductive surgery (n = 128). Molecular profiling and survival analyses were restricted to the primary cytoreductive surgery cohort due to tissue availability. All patients underwent germline testing for HRD- and MSI-related gene mutations. When sufficient tissue was available, screening for somatic BRCA1/2 mutations, BRCA1 promoter methylation, HRD score (a measure of genomic instability), MSI, and TMB testing were performed. HRD score ≥33 was associated with improved overall survival on multivariable analysis. In the era of biomarker-driven clinical care, HRD score ≥33 may be a useful adjunctive prognostic tool and should be evaluated in future studies to predict PARPi benefits.
Anti-Cancer Drugs Targeting Protein Kinases Approved by FDA in 2020
Authors: Cicenas Jonas , Račienė Asta
Published: February 2021

Cancers are a large group of diseases that mostly emerge because of the uncontrollable action of many different genes in human cells [...]
Prognostic Significance of Prostate-Specific Antigen Persistence after Radical Prostatectomy: A Systematic Review and Meta-Analysis
Authors: Kimura Shoji , Urabe Fumihiko , Sasaki Hiroshi , Kimura Takahiro , Miki Kenta , Egawa Shin
Published: February 2021

We performed a systematic review and meta-analysis to assess the prognostic value of prostate-specific antigen (PSA) persistence 4–8 weeks after radical prostatectomy (RP) in patients with prostate cancer, using studies from Medline, Scopus, and Cochrane Library, on 10 October 2020. Studies were eligible if they compared patients with postoperative PSA persistence 4–8 weeks after RP to those without such persistence to assess the value of PSA persistence in prognosticating biochemical recurrence (BCR), disease recurrence, cancer-specific mortality (CSM), and overall mortality (OM) by multivariable analysis. Our review and analysis included nine studies published between 2008 and 2019 with 14,455 patients. Of those studies, 12.0% showed postoperative PSA persistence. PSA persistence was associated with BCR (HR: 4.44, 95% CI: 2.84–6.93), disease recurrence (HR: 3.43, 95% CI: 1.62–7.25), and CSM (HR: 2.32, 95% CI: 1.83–2.95). We omitted meta-analysis on the association of PSA persistence with OM due to an insufficient number of studies. PSA persistence was associated with disease recurrence in a sub-group of patients with pathological nodal involvement (HR: 5.90, 95% CI: 3.76–9.24). Understanding detection of PSA persistence at 4–8 weeks after RP might be useful for patient counseling, follow-up scheduling, and clinical decision-making regarding adjuvant therapies.
HIV-1 Protease Inhibitors Slow HPV16-Driven Cell Proliferation through Targeted Depletion of Viral E6 and E7 Oncoproteins
Authors: Park Soyeong , Auyeung Andrew , Lee Denis L. , Lambert Paul F. , Carchman Evie H. , Sherer Nathan M.
Published: February 2021

High-risk human papillomavirus strain 16 (HPV16) causes oral and anogenital cancers through the activities of two viral oncoproteins, E6 and E7, that dysregulate the host p53 and pRb tumor suppressor pathways, respectively. The maintenance of HPV16-positive cancers requires constitutive expression of E6 and E7. Therefore, inactivating these proteins could provide the basis for an anticancer therapy. Herein we demonstrate that a subset of aspartyl protease inhibitor drugs currently used to treat HIV/AIDS cause marked reductions in HPV16 E6 and E7 protein levels using two independent cell culture models: HPV16-transformed CaSki cervical cancer cells and NIKS16 organotypic raft cultures (a 3-D HPV16-positive model of epithelial pre-cancer). Treatment of CaSki cells with some (lopinavir, ritonavir, nelfinavir, and saquinavir) but not other (indinavir and atazanavir) protease inhibitors reduced E6 and E7 protein levels, correlating with increased p53 protein levels and decreased cell viability. Long-term (>7 day) treatment of HPV16-positive NIKS16 raft cultures with saquinavir caused epithelial atrophy with no discernible effects on HPV-negative rafts, demonstrating selectivity. Saquinavir also reduced HPV16′s effects on markers of the cellular autophagy pathway in NIKS16 rafts, a hallmark of HPV-driven pre-cancers. Taken together, these data suggest HIV-1 protease inhibitors be studied further in the context of treating or preventing HPV16-positive cancers.
ARID1A and CTNNB1/β-Catenin Molecular Status Affects the Clinicopathologic Features and Prognosis of Endometrial Carcinoma: Implications for an Improved Surrogate Molecular Classification
Authors: De Leo Antonio , de Biase Dario , Lenzi Jacopo , Barbero Giovanna , Turchetti Daniela , Grillini Marco , Ravegnini Gloria , Angelini Sabrina , Zamagni Claudio , Coluccelli Sara , Dondi Giulia , De Iaco Pierandrea , Perrone Anna Myriam , Tallini Giovanni , Santini Donatella , Ceccarelli Claudio
Published: February 2021

The collaborative Cancer Genome Atlas (TCGA) project identified four distinct prognostic groups of endometrial carcinoma (EC) based on molecular alterations: (i) the ultramutated subtype that encompasses POLE mutated (POLE) cases; (ii) the hypermutated subtype, characterized by MisMatch Repair deficiency (MMRd); (iii) the copy-number high subtype, with p53 abnormal/mutated features (p53abn); (iv) the copy-number low subtype, known as No Specific Molecular Profile (NSMP). Although the prognostic value of TCGA molecular classification, NSMP carcinomas present a wide variability in molecular alterations and biological aggressiveness. This study aims to investigate the impact of ARID1A and CTNNB1/β-catenin alterations by targeted Next-generation sequencing (NGS) and immunohistochemistry (IHC) in a consecutive series of 125 molecularly classified ECs. NGS and IHC were used to assign surrogate TCGA groups and to identify molecular alterations of multiple target genes including POLE, PTEN, ARID1A, CTNNB1, TP53. Associations with clinicopathologic parameters, molecular subtypes, and outcomes identified NSMP category as the most heterogeneous group in terms of clinicopathologic features and outcome. Integration of surrogate TCGA molecular classification with ARID1A and β-catenin analysis showed NSMP cases with ARID1A mutation characterized by the worst outcome with early recurrence, while NSMP tumors with ARID1A wild-type and β-catenin alteration had indolent clinicopathologic features and no recurrence. This study indicates how the identification of ARID1A and β-catenin alterations in EC represents a simple and effective way to characterize NSMP tumor aggressiveness and metastatic potential.
Panax ginseng-Derived Extracellular Vesicles Facilitate Anti-Senescence Effects in Human Skin Cells: An Eco-Friendly and Sustainable Way to Use Ginseng Substances
Authors: Cho Eun-Gyung , Choi Suh-Yeon , Kim Hyoseon , Choi Eun-Jeong , Lee Eun-Jeong , Park Phil-Jun , Ko Jaeyoung , Kim Kwang Pyo , Baek Heung Soo
Published: February 2021

Ginseng is a traditional herbal medicine in eastern Asian countries. Most active constituents in ginseng are prepared via fermentation or organic acid pretreatment. Extracellular vesicles (EVs) are released by most organisms from prokaryotes to eukaryotes and play central roles in intra- and inter-species communications. Plants produce EVs upon exposure to microbes; however, their direct functions and utility for human health are barely known, except for being proposed as delivery vehicles. In this study, we isolated EVs from ginseng roots (GrEVs) or the culture supernatants of ginseng cells (GcEVs) derived from Panax ginseng C.A. Meyer and investigated their biological effects on human skin cells. GrEV or GcEV treatments improved the replicative senescent or senescence-associated pigmented phenotypes of human dermal fibroblasts or ultraviolet B radiation-treated human melanocytes, respectively, by downregulating senescence-associated molecules and/or melanogenesis-related proteins. Based on comprehensive lipidomic analysis using liquid chromatography mass spectrometry, the lipidomic profile of GrEVs differed from that of the parental root extracts, showing significant increases in 70 of 188 identified lipid species and prominent increases in diacylglycerols, some phospholipids (phosphatidylcholine, phosphatidylethanolamine, lysophosphatidylcholine), and sphingomyelin, revealing their unique vesicular properties. Therefore, our results imply that GEVs represent a novel type of bioactive and sustainable nanomaterials that can be applied to human tissues for improving tissue conditions and targeted delivery of active constituents.
CLTA-4 Expression Is Associated with the Maintenance of Chronic Inflammation in Endometriosis and Infertility
Authors: Abramiuk Monika , Bębnowska Dominika , Hrynkiewicz Rafał , Niedźwiedzka-Rystwej Paulina , Polak Grzegorz , Kotarski Jan , Roliński Jacek , Grywalska Ewelina
Published: February 2021

Altered immune mechanisms are implicated in the pathogenesis of endometriosis. CTLA-4 is a membrane receptor that favors the anergic state of lymphocytes, which may disrupt the immune system response in the endometriotic environment. In this study, we examined the expression of CTLA-4 on T and B cells by flow cytometry and its levels in blood serum and peritoneal fluid by ELISA. Levels of CTLA-4+ T cells were significantly higher in patients with more advanced endometriosis than in those with less advanced disease. Additionally, the negative correlation of CTLA-4+ T lymphocytes and the percentage of NK and NKT-like cells in women with endometriosis and infertility may indicate a different etiopathogenesis of endometriosis accompanying infertility. Our findings shed light on the potential of CTLA-4 in developing new diagnostic and therapeutic approaches in endometriosis management.
Internal Structure and Temporal Stability of Hard X-ray Pd/B4C Multilayer Mirrors under Different Humidity Environments
Authors: Liu Genchang , Huang Qiushi , Qi Runze , Ni Hangjian , Feng Yufei , Zhang Zhong , Wang Zhanshan
Published: February 2021

Pd/B4C multilayers with 2.5 nm of d-spacing and thick Si and B4C capping layers were fabricated to study temporal stability under storage in different environments with relative humidity of 10% and 50%. The two stored samples were investigated using grazing incidence X-ray reflectometry (GIXR), X-ray scattering (XRS), an optical microscope, transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The GIXR results showed that the reflectivity of the samples under 10% humidity and 50% humidity dropped by 3% and 8%, respectively, after 13 months. The optical microscope showed that the surface of the 10% humidity sample was smooth and undamaged, whereas the surface of the 50% humidity sample significantly eroded. TEM showed that the internal multilayer structure of the sample stored in 10% humidity was well protected by the capping layers. For the sample stored in 50% humidity, a major part of the Si and B4C capping layers were wrinkled and delaminated, and some surface layers of the multilayer structure were degraded with severe diffusion of boron. The XPS results showed a relatively large amount of oxygen in the B4C capping layer of the 50% humidity sample, and an obvious oxidation of the boron was found in the B4C capping layer and the surface of the multilayer. The severe oxidation and diffusion of boron and the delamination of the capping layers caused the degradation of the Pd/B4C multilayers stored in 50% humidity.
Investigation of the Wear Behavior of PVD Coated Carbide Tools during Ti6Al4V Machining with Intensive Built Up Edge Formation
Authors: Chowdhury M.S.I. , Bose B. , Rawal S. , Fox-Rabinovich G.S. , Veldhuis S.C.
Published: February 2021

Tool wear phenomena during the machining of titanium alloys are very complex. Severe adhesive interaction at the tool chip interface, especially at low cutting speeds, leads to intensive Built Up Edge (BUE) formation. Additionally, a high cutting temperature causes rapid wear in the carbide inserts due to the low thermal conductivity of titanium alloys. The current research studies the effect of AlTiN and CrN PVD coatings deposited on cutting tools during the rough turning of a Ti6Al4V alloy with severe BUE formation. Tool wear characteristics were evaluated in detail using a Scanning Electron Microscope (SEM) and volumetric wear measurements. Chip morphology analysis was conducted to assess the in situ tribological performance of the coatings. A high temperature–heavy load tribometer that mimics machining conditions was used to analyze the frictional behavior of the coatings. The micromechanical properties of the coatings were also investigated to gain a better understanding of the coating performance. It was demonstrated that the CrN coating possess unique micromechanical properties and tribological adaptive characteristics that minimize BUE formation and significantly improve tool performance during the machining of the Ti6Al4V alloy.
Application of PAT-Based Feedback Control Approaches in Pharmaceutical Crystallization
Authors: Gao Ye , Zhang Teng , Ma Yiming , Xue Fumin , Gao Zhenguo , Hou Baohong , Gong Junbo
Published: February 2021

Crystallization is one of the important unit operations for the separation and purification of solid products in the chemical, pharmaceutical, and pesticide industries, especially for realizing high-end, high-value solid products. The precise control of the solution crystallization process determines the polymorph, crystal shape, size, and size distribution of the crystal product, which is of great significance to improve product quality and production efficiency. In order to develop the crystallization process in a scientific method that is based on process parameters and data, process analysis technology (PAT) has become an important enabling platform. In this paper, we review the development of PAT in the field of crystallization in recent years. Based on the current research status of drug crystallization process control, the monitoring methods and control strategies of feedback control in the crystallization process were systematically summarized. The focus is on the application of model-free feedback control strategies based on the solution and solid information collected by various online monitoring equipment in product engineering, including improving particle size distribution, achieving polymorphic control, and improving purity. In this paper, the challenges of feedback control strategy in the crystallization process are also discussed, and the development trend of the feedback control strategy has been prospected.
Choroidal Vascularity Features in Patients with Choroideremia and Cystoid Spaces
Authors: Iovino Claudio , Di Iorio Valentina , Testa Francesco , Bombace Viviana , Melillo Paolo , Vupparaboina Kiran Kumar , Chhablani Jay , Simonelli Francesca
Published: February 2021

Cystoid spaces (CSs) are a common retinal finding in choroideremia (CHM) patients. The aim of this study was to analyze the vascular features of the choroid associated with the presence of CSs in patients with confirmed genetic diagnosis of CHM. A total of 33 patients (33 eyes) were enrolled in this retrospective cross-sectional study and divided into two groups based on the presence (17 eyes) or absence (16 eyes) of CSs. Choroidal features were evaluated on spectral-domain optical coherence tomography including subfoveal choroidal thickness (CT), total choroidal area (TCA), luminal choroidal area (LCA), and stromal choroidal area (SCA). The choroidal vascularity index (CVI) was then calculated in all study eyes. All structural choroidal parameters were calculated both on the entire length of the B-scan and in the central subfoveal 1500 μm. The average age was 37.3 ± 11.6 and 31.4 ± 16.7 years (p = 0.25) and mean logMAR best-corrected visual acuity was 0.11 ± 0.20 and 0.20 ± 0.57 (p = 0.54) in the CHM groups with and without CSs, respectively. There were no significant differences in subfoveal CT, and TCA, LCA, SCA, and CVI evaluated on either the entire scan or in the central 1500 μm (all p > 0.05). All choroidal vasculature parameters exhibited no significant differences between CHM eyes with and without CSs. Our results suggest that the choroid may not be involved in the development of CSs in patients with CHM.
Isolation of Extracellular Vesicles from Biological Fluids via the Aggregation–Precipitation Approach for Downstream miRNAs Detection
Authors: Konoshenko Maria Y. , Lekchnov Evgeniy A. , Bryzgunova Olga E. , Kiseleva Elena , Pyshnaya Inna A. , Laktionov Pavel P.
Published: February 2021

Extracellular vesicles (EVs) have high potential as sources of biomarkers for non-invasive diagnostics. Thus, a simple and productive method of EV isolation is demanded for certain scientific and medical applications of EVs. Here we aim to develop a simple and effective method of EV isolation from different biofluids, suitable for both scientific, and clinical analyses of miRNAs transported by EVs. The proposed aggregation–precipitation method is based on the aggregation of EVs using dextran blue and the subsequent precipitation of EVs using 1.5% polyethylene glycol solutions. The developed method allows the effective isolation of EVs from plasma and urine. As shown using TEM, dynamic light scattering, and miRNA analyses, this method is not inferior to ultracentrifugation-based EV isolation in terms of its efficacy, lack of inhibitors for polymerase reactions and applicable for both healthy donors and cancer patients. This method is fast, simple, does not need complicated equipment, can be adapted for different biofluids, and has a low cost. The aggregation–precipitation method of EV isolation accessible and suitable for both research and clinical laboratories. This method has the potential to increase the diagnostic and prognostic utilization of EVs and miRNA-based diagnostics of urogenital pathologies.
Diagnosis of COVID-19 in Patients with Negative Nasopharyngeal Swabs: Reliability of Radiological and Clinical Diagnosis and Accuracy Versus Serology
Authors: Mirijello Antonio , Zarrelli Michele , Miscio Giuseppe , de Matthaeis Angela , Piscitelli Pamela , Carbonelli Cristiano , Di Giorgio Annabella , Inglese Michele , Ciliberti Gianluca , Marciano Carmen , Borelli Cristina , Vergara Doriana , Castorani Giulia , Orciulo Grazia , Di Mauro Lazzaro , Carella Massimo , Simeone Annalisa , Copetti Massimiliano , Leone Maurizio , De Cosmo Salvatore , the CSS-COVID-Group
Published: February 2021

Background: The diagnosis of Coronavirus disease 2019 (COVID-19) relies on the positivity of nasopharyngeal swab. However, a significant percentage of symptomatic patients may test negative. We evaluated the reliability of COVID-19 diagnosis made by radiologists and clinicians and its accuracy versus serology in a sample of patients hospitalized for suspected COVID-19 with multiple negative swabs. Methods: Admission chest CT-scans and clinical records of swab-negative patients, treated according to the COVID-19 protocol or deceased during hospitalization, were retrospectively evaluated by two radiologists and two clinicians, respectively. Results: Of 254 patients, 169 swab-confirmed cases and one patient without chest CT-scan were excluded. A total of 84 patients were eligible for the reliability study. Of these, 21 patients died during hospitalization; the remaining 63 underwent serological testing and were eligible for the accuracy evaluation. Of the 63, 26 patients showed anti-Sars-Cov-2 antibodies, while 37 did not. The inter-rater agreement was “substantial” (kappa 0.683) between radiologists, “moderate” (kappa 0.454) between clinicians, and only “fair” (kappa 0.341) between radiologists and clinicians. Both radiologic and clinical evaluations showed good accuracy compared to serology. Conclusions: The radiologic and clinical diagnosis of COVID-19 for swab-negative patients proved to be sufficiently reliable and accurate to allow a diagnosis of COVID-19, which needs to be confirmed by serology and follow-up.
Fault Detection Based on Multi-Dimensional KDE and Jensen–Shannon Divergence
Authors: Wei Juhui , He Zhangming , Wang Jiongqi , Wang Dayi , Zhou Xuanying
Published: February 2021

Weak fault signals, high coupling data, and unknown faults commonly exist in fault diagnosis systems, causing low detection and identification performance of fault diagnosis methods based on T2 statistics or cross entropy. This paper proposes a new fault diagnosis method based on optimal bandwidth kernel density estimation (KDE) and Jensen–Shannon (JS) divergence distribution for improved fault detection performance. KDE addresses weak signal and coupling fault detection, and JS divergence addresses unknown fault detection. Firstly, the formula and algorithm of the optimal bandwidth of multidimensional KDE are presented, and the convergence of the algorithm is proved. Secondly, the difference in JS divergence between the data is obtained based on the optimal KDE and used for fault detection. Finally, the fault diagnosis experiment based on the bearing data from Case Western Reserve University Bearing Data Center is conducted. The results show that for known faults, the proposed method has 10% and 2% higher detection rate than T2 statistics and the cross entropy method, respectively. For unknown faults, T2 statistics cannot effectively detect faults, and the proposed method has approximately 15% higher detection rate than the cross entropy method. Thus, the proposed method can effectively improve the fault detection rate.
Short-Term HRV Analysis Using Nonparametric Sample Entropy for Obstructive Sleep Apnea
Authors: Liang Duan , Wu Shan , Tang Lan , Feng Kaicheng , Liu Guanzheng
Published: February 2021

Obstructive sleep apnea (OSA) is associated with reduced heart rate variability (HRV) and autonomic nervous system dysfunction. Sample entropy (SampEn) is commonly used for regularity analysis. However, it has limitations in processing short-term segments of HRV signals due to the extreme dependence of its functional parameters. We used the nonparametric sample entropy (NPSampEn) as a novel index for short-term HRV analysis in the case of OSA. The manuscript included 60 6-h electrocardiogram recordings (20 healthy, 14 mild-moderate OSA, and 26 severe OSA) from the PhysioNet database. The NPSampEn value was compared with the SampEn value and frequency domain indices. The empirical results showed that NPSampEn could better differentiate the three groups (p < 0.01) than the ratio of low frequency power to high frequency power (LF/HF) and SampEn. Moreover, NPSampEn (83.3%) approached a higher OSA screening accuracy than the LF/HF (73.3%) and SampEn (68.3%). Compared with SampEn (|r| = 0.602, p < 0.05), NPSampEn (|r| = 0.756, p < 0.05) had a significantly stronger association with the apnea-hypopnea index (AHI). Hence, NPSampEn can fully overcome the influence of individual differences that are prevalent in biomedical signal processing, and might be useful in processing short-term segments of HRV signal.
Thermoelectric Sensor Coupled Yagi–Uda Nanoantenna for Infrared Detection
Authors: Sethi Waleed Tariq , De Sagazan Olivier , Himdi Mohamed , Vettikalladi Hamsakutty , Alshebeili Saleh A.
Published: February 2021

We present an experimental demonstration of a thermoelectric sensor coupled with a nanoantenna as an alternative option for detecting infrared energy. Two nanoantenna design (single element and an array) variations based on Yagi-Uda technology and one separate nano-thermoelectric junction array were fabricated and tested. The nanoantennas were tuned to operate and respond at a center wavelength of 1550 nm (193.5 THz) optical C-band window, but they also exhibited a resonance response when excited by lasers of various wavelengths (650 nm and 940 nm). The radiation-induced electric currents in the nanoantennas, coupled with a nano-thermoelectric sensor, produced a potential difference as per the Seebeck effect. With respect to the uniform thermal measurements of the reference nanoantenna, the experiments confirmed the detection properties of the proposed nanoantennas; the single element detected a peak percentage voltage hike of 28%, whereas the array detected a peak percentage voltage hike of 80% at the center wavelength. Compared to state-of-the-art thermoelectric designs, this was the first time that such peak percentage voltages were experimentally reported following a planar design based on the Seebeck principle.
A Highly Configurable High-Level Synthesis Functional Pattern Library
Authors: Huang Lan , Gao Teng , Li Dalin , Wang Zihao , Wang Kangping
Published: February 2021

FPGA has recently played an increasingly important role in heterogeneous computing, but Register Transfer Level design flows are not only inefficient in design, but also require designers to be familiar with the circuit architecture. High-level synthesis (HLS) allows developers to design FPGA circuits more efficiently with a more familiar programming language, a higher level of abstraction, and automatic adaptation of timing constraints. When using HLS tools, such as Xilinx Vivado HLS, specific design patterns and techniques are required in order to create high-performance circuits. Moreover, designing efficient concurrency and data flow structures requires a deep understanding of the hardware, imposing more learning costs on programmers. In this paper, we propose a set of functional patterns libraries based on the MapReduce model, implemented by C++ templates, which can quickly implement high-performance parallel pipelined computing models on FPGA with specified simple parameters. The usage of this pattern library allows flexible adaptation of parallel and flow structures in algorithms, which greatly improves the coding efficiency. The contributions of this paper are as follows. (1) Four standard functional operators suitable for hardware parallel computing are defined. (2) Functional concurrent programming patterns are described based on C++ templates and Xilinx HLS. (3) The efficiency of this programming paradigm is verified with two algorithms with different complexity.
Research on EDAC Schemes for Memory in Space Applications
Authors: Chen Mengfu , Guo Chenguang , Chen Lei , Li Wenjie , Zhang Fan , Hu Xiaoxiang , Xu Jiancheng
Published: February 2021

Memory used for storing the configuration bitstream of field programmable gate array in space applications often encounters single event upset problems, which may disrupt the integrity of data in memory and lead to unpredictable failures. For commercial memories used in low Earth orbit (LEO), single-bit errors and double-byte errors account for a large proportion. Meanwhile, error detection and correction (EDAC) schemes, e.g., triple modular redundancy, linear block codes, memory scrubbing, and the combination of these schemes, are very popular in LEO missions. To further these works, a novel EDAC scheme with cascaded “Bose–Chaudhuri–Hocquenghem and cyclic redundancy check” codes and a proper scrubbing method is presented in this paper. The performance of the proposed design is measured and compared with state-of-the-art EDAC schemes in terms of hardware overhead, time overhead and error correction and detection capabilities. It is concluded that the proposed EDAC scheme is better suited for memory in space applications.
High-Accuracy Power Quality Disturbance Classification Using the Adaptive ABC-PSO as Optimal Feature Selection Algorithm
Authors: Chamchuen Supanat , Siritaratiwat Apirat , Fuangfoo Pradit , Suthisopapan Puripong , Khunkitti Pirat
Published: February 2021

Power quality disturbance (PQD) is an important issue in electrical distribution systems that needs to be detected promptly and identified to prevent the degradation of system reliability. This work proposes a PQD classification using a novel algorithm, comprised of the artificial bee colony (ABC) and the particle swarm optimization (PSO) algorithms, called “adaptive ABC-PSO” as the feature selection algorithm. The proposed adaptive technique is applied to a combination of ABC and PSO algorithms, and then used as the feature selection algorithm. A discrete wavelet transform is used as the feature extraction method, and a probabilistic neural network is used as the classifier. We found that the highest classification accuracy (99.31%) could be achieved through nine optimally selected features out of all 72 extracted features. Moreover, the proposed PQD classification system demonstrated high performance in a noisy environment, as well as the real distribution system. When comparing the presented PQD classification system’s performance to previous studies, PQD classification accuracy using adaptive ABC-PSO as the optimal feature selection algorithm is considered to be at a high-range scale; therefore, the adaptive ABC-PSO algorithm can be used to classify the PQD in a practical electrical distribution system.
AC Magnetic Loss Reduction of SLM Processed Fe-Si for Additive Manufacturing of Electrical Machines
Authors: Tiismus Hans , Kallaste Ants , Belahcen Anouar , Tarraste Marek , Vaimann Toomas , Rassõlkin Anton , Asad Bilal , Shams Ghahfarokhi Payam
Published: February 2021

Additively manufactured soft magnetic Fe-3.7%w.t.Si toroidal samples with solid and novel partitioned cross-sectional geometries are characterized through magnetic measurements. This study focuses on the effect of air gaps and annealing temperature on AC core losses at the 50 Hz frequency. In addition, DC electromagnetic material properties are presented, showing comparable results to conventional and other 3D-printed, high-grade, soft magnetic materials. The magnetization of 1.5 T was achieved at 1800 A/m, exhibiting a maximum relative permeability of 28,900 and hysteresis losses of 0.61 (1 T) and 1.7 (1.5 T) W/kg. A clear trend of total core loss reduction at 50 Hz was observed in relation to the segregation of the specimen cross-sectional topology. The lowest 50 Hz total core losses were measured for the toroidal specimen with four internal air gaps annealed at 1200 °C, exhibiting a total core loss of 1.2 (1 T) and 5.5 (1.5 T) W/kg. This is equal to an 860% total core loss reduction at 1 T and a 510% loss reduction at 1.5 T magnetization compared to solid bulk-printed material. Based on the findings, the advantages and disadvantages of printed air-gapped material internal structures are discussed in detail.
Producing Energy-Rich Microalgae Biomass for Liquid Biofuels: Influence of Strain Selection and Culture Conditions
Authors: Heredia Vladimir , Gonçalves Olivier , Marchal Luc , Pruvost Jeremy
Published: February 2021

Energy-storage metabolites such as neutral lipids and carbohydrates are valuable compounds for liquid biofuel production. The aim of this work is to elucidate the main biological responses of two algae species known for their effective energy-rich compound accumulation in nitrogen limitation and day–night cycles: Nannochloropsis gaditana, a seawater species, and Parachlorella kessleri, a freshwater species. Lipid and carbohydrate production are investigated, as well as cell resistance to mechanical disruption for energy-rich compound release. Nitrogen-depleted N. gaditana showed only a low consumption of energy-storage molecules with a non-significant preference for neutral lipids (TAG) and carbohydrates in day–night cycles. However, it did accumulate significantly fewer carbohydrates than P. kessleri. Following this, the highest levels of productivity for N. gaditana in chemostat cultures at four levels of nitrogen limitation were found to be 3.4 and 2.2 × 10−3 kg/m2·d for carbohydrates and TAG, respectively, at 56%NO3 limitation. The cell disruption rate of N. gaditana decreased along with nitrogen limitation, from 75% (at 200%NO3) to 17% (at 13%NO3). In the context of potentially recoverable energy for biofuels, P. kessleri showed good potential for biodiesel and high potential for bioethanol; by contrast, N. gaditana was found to be more efficient for biodiesel production only.
Attenuation of Zero Sequence Voltage Using a Conventional Three-Wire Dynamic Voltage Restorer
Authors: Neto Rafael , Landera Yandi , Neves Francisco , de Souza Helber , Cavalcanti Marcelo , Azevedo Gustavo
Published: February 2021

Voltage sags/swells and harmonics are recurring problems in electric energy distribution systems. In order to solve these issues, several dynamic voltage restorer (DVR) topologies, such as the conventional three-wire DVR, have been proposed in the literature. Despite its capability of mitigating voltage disturbances, many researchers have established that conventional three-wire DVR cannot compensate for zero sequence voltage disturbances. In this paper, an in-depth study of the conventional three-phase DVR is presented, which shows that this DVR topology can also be used to attenuate zero sequence voltage components without increasing control complexity. The necessary conditions for this to occur are discussed in details and a brief comparison between the conventional three-wire DVR and other DVR topologies that can compensate for zero sequence voltage disturbances is made. Experimental results are included to validate the theoretical study.