bluuebunny/crossref_metadata_2025 huggingface dataset:
Progression-Free Survival and Overall Survival in Patients with Advanced HER2-Positive Breast Cancer Treated with Trastuzumab Emtansine (T-DM1) after Previous Treatment with Pertuzumab
Authors: Michel Laura L. , Hartkopf Andreas D. , Fasching Peter A. , Kolberg Hans-Christian , Hadji Peyman , Tesch Hans , Häberle Lothar , Ettl Johannes , Lüftner Diana , Wallwiener Markus , Müller Volkmar , Beckmann Matthias W. , Belleville Erik , Volz Bernhard , Huebner Hanna , Wimberger Pauline , Hielscher Carsten , Mundhenke Christoph , Kurbacher Christian , Wuerstlein Rachel , Untch Michael , Overkamp Friedrich , Huober Jens , Janni Wolfgang , Taran Florin-Andrei , Lux Michael P. , Wallwiener Diethelm , Brucker Sara Y. , Schneeweiss Andreas , Fehm Tanja N.
Published: October 2020

The approval of trastuzumab emtansine (T-DM1) was conducted without pertuzumab as previous therapy. Efficacy data on T-DM1 following pertuzumab treatment are therefore limited. This study explores this issue in a real-world setting. Within the prospective PRAEGNANT (Prospective Academic Translational Research Network for the Optimization of the Oncological Health Care Quality in the Advanced Setting) metastatic breast cancer registry (NCT02338167), patients in all therapy lines receiving any kind of treatment were eligible for inclusion. This report describes patient characteristics and progression-free survival (PFS) in human epidermal growth factor receptor 2 (HER2)-positive patients receiving T-DM1 after pertuzumab treatment. Seventy-six patients were identified, 39 of whom received T-DM1 as second-line therapy, 25 as third-line, and 12 as fourth-line therapy or higher. Pertuzumab was mostly administered as a first-line treatment (n = 61; 80.3%). The median PFS in all patients was 3.5 months (95% CI: 2.8–7.8); in second-line treatment, 7.7 months (95% CI: 2.8–11.0); in third-line, 3.4 months (95% CI: 2.3–not reached (NR)); and in fourth-line therapy or higher, 2.7 months (95% CI: 1.2–NR). T-DM1 was mainly administered second-line after pertuzumab, but also in more heavily pretreated patients. The PFS in higher therapy lines appears to be shorter than in second-line.
Dissecting the Crosstalk between NRF2 Signaling and Metabolic Processes in Cancer
Authors: DeBlasi Janine M. , DeNicola Gina M.
Published: October 2020

The transcription factor NRF2 (nuclear factor-erythroid 2 p45-related factor 2 or NFE2L2) plays a critical role in response to cellular stress. Following an oxidative insult, NRF2 orchestrates an antioxidant program, leading to increased glutathione levels and decreased reactive oxygen species (ROS). Mounting evidence now implicates the ability of NRF2 to modulate metabolic processes, particularly those at the interface between antioxidant processes and cellular proliferation. Notably, NRF2 regulates the pentose phosphate pathway, NADPH production, glutaminolysis, lipid and amino acid metabolism, many of which are hijacked by cancer cells to promote proliferation and survival. Moreover, deregulation of metabolic processes in both normal and cancer-based physiology can stabilize NRF2. We will discuss how perturbation of metabolic pathways, including the tricarboxylic acid (TCA) cycle, glycolysis, and autophagy can lead to NRF2 stabilization, and how NRF2-regulated metabolism helps cells deal with these metabolic stresses. Finally, we will discuss how the negative regulator of NRF2, Kelch-like ECH-associated protein 1 (KEAP1), may play a role in metabolism through NRF2 transcription-independent mechanisms. Collectively, this review will address the interplay between the NRF2/KEAP1 complex and metabolic processes.
Retinoic Acid Sensitivity of Triple-Negative Breast Cancer Cells Characterized by Constitutive Activation of the notch1 Pathway: The Role of Rarβ
Authors: Paroni Gabriela , Zanetti Adriana , Barzago Maria Monica , Kurosaki Mami , Guarrera Luca , Fratelli Maddalena , Troiani Martina , Ubezio Paolo , Bolis Marco , Vallerga Arianna , Biancardi Federica , Terao Mineko , Garattini Enrico
Published: October 2020

Triple-negative breast cancer (TNBC) is a heterogeneous disease that lacks effective therapeutic options. In this study, we profile eighteen TNBC cell lines for their sensitivity to the anti-proliferative action of all-trans retinoic acid (ATRA). The only three cell lines (HCC-1599, MB-157 and MDA-MB-157) endowed with ATRA-sensitivity are characterized by genetic aberrations of the NOTCH1-gene, causing constitutive activation of the NOTCH1 γ-secretase product, N1ICD. N1ICD renders HCC-1599, MB-157 and MDA-MB-157 cells sensitive not only to ATRA, but also to γ-secretase inhibitors (DAPT; PF-03084014). Combinations of ATRA and γ-secretase inhibitors produce additive/synergistic effects in vitro and in vivo. RNA-sequencing studies of HCC-1599 and MB-157 cells exposed to ATRA and DAPT and ATRA+DAPT demonstrate that the two compounds act on common gene sets, some of which belong to the NOTCH1 pathway. ATRA inhibits the growth of HCC-1599, MB-157 and MDA-MB-157 cells via RARα, which up-regulates several retinoid target-genes, including RARβ. RARβ is a key determinant of ATRA anti-proliferative activity, as its silencing suppresses the effects exerted by the retinoid. In conclusion, we demonstrate that ATRA exerts a significant anti-tumor action only in TNBC cells showing constitutive NOTCH1 activation. Our results support the design of clinical trials involving combinations between ATRA and γ-secretase inhibitors for the treatment of this TNBC subtype.
Ionizing Irradiation Induces Vascular Damage in the Aorta of Wild-Type Mice
Authors: Hamada Nobuyuki , Kawano Ki-ichiro , Yusoff Farina Mohamad , Furukawa Kyoji , Nakashima Ayumu , Maeda Makoto , Yasuda Hiroshi , Maruhashi Tatsuya , Higashi Yukihito
Published: October 2020

There has been a recent upsurge of interest in the effects of ionizing radiation exposure on the circulatory system, because a mounting body of epidemiological evidence suggests that irradiation induces cardio- and cerebrovascular disease at a much lower dose and lower dose rate than previously considered. The goal of our project is to determine whether dose protraction alters radiation effects on the circulatory system in a mouse model. To this end, the use of wild-type mice is pivotal albeit without manifestation of vascular diseases, because disease models (e.g., apolipoprotein E-deficient mice) are prone to hormetic responses following protracted exposures. As such, here, we first set out to analyze prelesional changes in the descending thoracic aorta of wild-type mice up to six months after a single acute exposure to 0 or 5 Gy of 137Cs γ-rays. Scanning electron microscopy demonstrated that irradiation facilitated structural disorganizations and detachment of the aortic endothelium. The Miles assay with an albumin-binding dye Evans Blue revealed that irradiation enhanced vascular permeability. Immunofluorescence staining showed that irradiation led to partial loss of the aortic endothelium (evidenced by a lack of adhesion molecule CD31 and 4′,6-diamidino-2-phenylindole (DAPI) signals), a decrease in endothelial nitric oxide synthase and adherens junction protein (vascular endothelial (VE)-cadherin) in the aortic endothelium, along with an increase in inflammation (tumor necrosis factor (TNF)-α) and macrophage (F4/80) markers in the aorta. These findings suggest that irradiation produces vascular damage manifested as endothelial cell loss and increased vascular permeability, and that the decreased adherens junction and the increased inflammation lead to macrophage recruitment implicated in the early stage of atherosclerosis.
The Experience of Oncology Healthcare Providers in the Central Italy during the COVID-19 Lockdown
Authors: Fabi Alessandra , Pugliese Patrizia , Falbo Pina Tiziana , Corsi Domenico , Fabbri Maria Agnese , Vincenzi Bruno , Bria Emilio , Angelini Francesco , Bonucci Alessandro , Pellegrino Arianna , Falcicchio Chiara , Caruso Anita , Giacomelli Luca , Mirisola Valentina , Papa Simonetta , Cognetti Francesco , Ciliberto Gennaro , Perrone Maria
Published: October 2020

While the emotional response of healthcare providers during the COVID-19 pandemic has been extensively investigated in countries in the Far-East, little is known about the psychological impact and the associated emotional distress of healthcare providers in Italy, especially with regard to different regions. The aim of the “VIRARE” survey, which was addressed to all the healthcare providers in the Lazio region (central Italy) and, in particular, to those working in the oncology field, is to analyze their opinion on the impact and management of the pandemic, to better understand the level of their psychological distress. A global good psychological response of healthcare providers to the pandemic has emerged, independently from their different occupations in the oncology field. Healthcare providers show a high degree of resilience, identifying the major causes of distress the difficulty of the management of this situation, the obstacles in their working activity and expressing a high degree of dissatisfaction with how Italian institutions handled this situation. This survey also provides a direct comparison between COVID-19-infected (or directly in contact with COVID-19-infected patients) and uninfected healthcare providers, identifying the sub-category of infected professionals that reported signs of depression as particularly vulnerable.
Completion Total Thyroidectomy Is Not Necessary for Papillary Thyroid Microcarcinoma with Occult Central Lymph Node Metastasis: A Long-Term Serial Follow-Up
Authors: Choi Soon Min , Kim Jin Kyong , Lee Cho Rok , Lee Jandee , Jeong Jong Ju , Nam Kee-Hyun , Chung Woong Youn , Kang Sang-Wook
Published: October 2020

The necessity of completion total thyroidectomy in patients with papillary thyroid microcarcinoma (PTMC) and pathological central lymph node metastasis (pCLNM) who underwent thyroid lobectomy with central compartment neck dissection (CCND) is unclear. We determined the necessity of completion total thyroidectomy by retrospectively comparing the prognosis according to the presence of pCLNM during a long-term follow-up. We enrolled 876 patients with PTMC who underwent thyroid lobectomy with prophylactic CCND from January 1986 to December 2009. Patients were divided according to central lymph node (CLN) metastasis: 165 (18.8%) and 711 (81.2%) in the CLN-positive and CLN-negative groups, respectively. Medical records were reviewed retrospectively, and clinicopathologic characteristics and recurrence rates were analyzed. The CLN-positive group was associated with male sex (p = 0.001), larger tumor size (p < 0.001), and more microscopic capsular invasion (p < 0.001) compared with the CLN-negative group. There was no significant difference between the two groups’ recurrence (p = 0.133) or disease-free (p = 0.065) survival rates. Univariate and multivariate analyses showed no factors associated with tumor recurrence except male sex (hazard ratio = 3.043, confidence interval 1.117–8.288, p = 0.030). Patients who were diagnosed with pCLNM after undergoing thyroid lobectomy with prophylactic CCND do not require completion total thyroidectomy; however, frequent follow-up is necessary for patients with PTMC and pCLNM.
Circulatory MIC-1 as a Determinant of Prostate Cancer Racial Disparity
Authors: Karan Dev , Wick Jo , Dubey Seema , Tawfik Ossama , Van Veldhuizen Peter
Published: October 2020

In this study, we investigated the potential of MIC-1 (macrophage inhibitory cytokine-1) on the severity of prostate cancer between African American men and Caucasians. Differences between the races were examined using Mann–Whitney tests for continuous variables and Fisher’s exact tests for categorical variables. Pearson’s correlation coefficient was used to identify associations between continuous measures across all samples and within each race. Analysis of variance, including clinical parameters, was used to identify differences in serum and urine MIC-1 levels between races. We found significant differences between the two races for age (p = 0.01), Gleason scores (p = 0.01), and stage of disease (p = 0.03). African American men in the study had higher Gleason scores (mean = 6.9) than Caucasians (mean = 6.5), during earlier stages of the disease. In Caucasian men with prostate cancer, serum MIC-1 expression was positively associated with age (r = 0.7, p < 0.01). However, African American men had highly expressed MIC-1 and high Gleason scores (r = 0.16, p = 0.3). Interestingly, the urine MIC-1 level was significantly higher in African American men with prostate cancer than in Caucasian patients. It appeared to be more sensitive and specific for African Americans (AUC = 0.85 vs. 0.56). Thus, high circulatory MIC-1 in prostate cancer patients may indicate MIC-1 as a potential biomarker to improve the diagnostic ability of an aggressive stage of prostate cancer in African American men. However, a larger cohort of sample analysis is required to validate these observations.
What Is New in Thyroid Cancer: The Special Issue of the Journal Cancers
Authors: Puxeddu Efisio , Tallini Giovanni , Vanni Roberta
Published: October 2020

The incidence of thyroid cancer has increased over the past 3 to 4 decades. Nonetheless, the mortality from thyroid cancer has remained stable. The thyroid gland may develop nodules encompassing several types of cell proliferation, from frankly benign to very aggressive forms with many intermediate challenging variants. For this reason, there is growing interest in evaluating thyroid nodules from many points of view, from the clinical to the molecular aspects, in the search for innovative diagnostic and prognostic parameters. The aim of this Special Issue was to provide an overview of recent developments in understanding the biology and molecular oncology of thyroid tumors of follicular cell derivation and their repercussions on the diagnosis, prognosis, and therapy. The contributions of many experts in the field made up a Special Issue of Cancers journal, that focusing on different aspects, including mechanistic and functional facets, gives the status of art of clinical and biological perspectives of thyroid cancer.
Epstein–Barr Virus Promotes B Cell Lymphomas by Manipulating the Host Epigenetic Machinery
Authors: Di Pietro Andrea
Published: October 2020

During the past decade, the rapid development of high-throughput next-generation sequencing technologies has significantly reinforced our understanding of the role of epigenetics in health and disease. Altered functions of epigenetic modifiers lead to the disruption of the host epigenome, ultimately inducing carcinogenesis and disease progression. Epstein–Barr virus (EBV) is an endemic herpesvirus that is associated with several malignant tumours, including B-cell related lymphomas. In EBV-infected cells, the epigenomic landscape is extensively reshaped by viral oncoproteins, which directly interact with epigenetic modifiers and modulate their function. This process is fundamental for the EBV life cycle, particularly for the establishment and maintenance of latency in B cells; however, the alteration of the host epigenetic machinery also contributes to the dysregulated expression of several cellular genes, including tumour suppressor genes, which can drive lymphoma development. This review outlines the molecular mechanisms underlying the epigenetic manipulation induced by EBV that lead to transformed B cells, as well as novel therapeutic interventions to target EBV-associated B-cell lymphomas.
CD73 Overexpression Promotes Progression and Recurrence of Papillary Thyroid Carcinoma
Authors: Jeong Young Mun , Cho Haejin , Kim Tae-Min , Kim Yourha , Jeon Sora , Bychkov Andrey , Jung Chan Kwon
Published: October 2020

CD73 is involved in tumor immune escape and promotes the growth and progression of cancer cells. The functional role of CD73 expression in papillary thyroid carcinoma (PTC) has not yet been established. In 511 patients with PTC, immunohistochemistry for CD73 on tissue microarrays showed that the high expression of CD73 was associated with an aggressive histologic variant (p = 0.002), extrathyroidal extension (p < 0.001), lymph node metastasis (p < 0.001), and BRAFV600E mutation (p = 0.015). Survival analysis results showed that patients with high CD73 expression had worse recurrence-free survival (p = 0.023). CD73 inhibitors induced G1 cell cycle arrest and apoptosis, inhibited the migration and invasion of PTC cells, and suppressed tumor growth in PTC xenograft nude mice. High expression of CD73 (NT5E) mRNA was associated with unfavorable clinicopathologic characteristics, the abundance of Tregs and dendritic cells, depletion of natural killer (NK) cells, and high expression of immune checkpoint genes and epithelial-to-mesenchymal transition-related genes in The Cancer Genome Atlas (TCGA) dataset. Taken together, CD73 expression promotes tumor progression and predicts low recurrence-free survival. Targeting the CD73–adenosine axis in the tumor microenvironment offers an attractive pathway for therapeutic strategies aimed at advanced PTC.
Large-Area Patterning of Oil-Based Inks on Superhydrophobic TiO2 Nanotubular Layers by Photocatalytic Wettability Conversion
Authors: Jin Jiao , Ren Huihui , Liu Zhaoyue
Published: October 2020

Patterning an oil-based ink on a solid surface based on a wettability difference is of significant importance for the application of offset printing. Herein, we describe a large-area patterning of oil-based ink on a self-organized TiO2 nanotubular layer based on a photocatalytic wettability conversion. The TiO2 nanotubular layer was fabricated by electrochemical anodization, which demonstrated a superhydrophobic wettability after modification with a self-assembled molecular layer. Subsequently, area-selective ultraviolet (UV) irradiation through a pre-designed pattern of water-based UV-resistant ink formed by an ink-jet technique was used to form a wettability difference. After removing the water-based ink, an oil-based ink was capable of depositing selectively on the superhydrophobic area to form the same pattern as the pre-designed pattern of water-based ink. This large-area patterning of an oil-based ink based on the photocatalytic wettability conversion is potentially applicable in offset printing.
Novel Insights into the Cellular Localization and Regulation of the Autophagosomal Proteins LC3A, LC3B and LC3C
Authors: Baeken Marius W. , Weckmann Katja , Diefenthäler Philip , Schulte Jan , Yusifli Kamran , Moosmann Bernd , Behl Christian , Hajieva Parvana
Published: October 2020

Macroautophagy is a conserved degradative process for maintaining cellular homeostasis and plays a key role in aging and various human disorders. The microtubule-associated protein 1A/1B light chain 3B (MAP1LC3B or LC3B) is commonly analyzed as a key marker for autophagosomes and as a proxy for autophagic flux. Three paralogues of the LC3 gene exist in humans: LC3A, LC3B and LC3C. The molecular function, regulation and cellular localization of LC3A and LC3C have not been investigated frequently, even if a similar function to that described for LC3B appears likely. Here, we have selectively decapacitated LC3B by three separate strategies in primary human fibroblasts and analyzed the evoked effects on LC3A, LC3B and LC3C in terms of their cellular distribution and co-localization with p62, a ubiquitin and autophagy receptor. First, treatment with pharmacological sirtuin 1 (SIRT1) inhibitors to prevent the translocation of LC3B from the nucleus into the cytosol induced an increase in cytosolic LC3C, a heightened co-localization of LC3C with p62, and an increase LC3C-dependent autophagic flux as assessed by protein lipidation. Cytosolic LC3A, however, was moderately reduced, but also more co-localized with p62. Second, siRNA-based knock-down of SIRT1 broadly reproduced these findings and increased the co-localization of LC3A and particularly LC3C with p62 in presumed autophagosomes. These effects resembled the effects of pharmacological sirtuin inhibition under normal and starvation conditions. Third, siRNA-based knock-down of total LC3B in cytosol and nucleus also induced a redistribution of LC3C as if to replace LC3B in the nucleus, but only moderately affected LC3A. Total protein expression of LC3A, LC3B, LC3C, GABARAP and GABARAP-L1 following LC3B decapacitation was unaltered. Our data indicate that nuclear trapping and other causes of LC3B functional loss in the cytosol are buffered by LC3A and actively compensated by LC3C, but not by GABARAPs. The biological relevance of the potential functional compensation of LC3B decapacitation by LC3C and LC3A warrants further study.
Influence of Sludge Initial pH on Bioleaching of Excess Sludge to Improve Dewatering Performance
Authors: Lin Shaonan , Shi Mingyan , Wang Jiade , Zhu Huijie , Wen Guicheng
Published: October 2020

pH has an important effect on the physiological activity of eosinophilic microorganisms. Therefore, this study used excess sludge produced by the mixed treatment of leachate and municipal sewage to explore the impact of different sludge initial pH on microbial biochemical reactions associated with the performance of excess sludge dehydration. Shake-flask tests were performed using inoculated microorganisms and fresh excess sludge in 500 mL Erlenmeyer flasks at a ratio of 1:4, with the addition of 2 g/L S0 and 6 g/L FeS2 as energy sources. Erlenmeyer flasks were shaken for 72 h at 180 rpm and 28 °C, in a reciprocating constant homeothermic oscillating water-bath. Results show that the specific resistance to filtration (SRF) of the bioleached excess sludge decreased from (1.45~6.68) × 1012 m/kg to (1.21~14.30) × 1011 m/kg and the sedimentation rate increased from 69.00~73.00% to 81.70~85.50%. The SRF decreased from 1.45 × 1012 m/kg to 1.21 × 1011 m/kg and the sedimentation rate increased from 69.00% to 85.00%, which both reached the highest level when the initial pH of the excess sludge was 5 and the bioleaching duration was 48 h. At this time, the rates of pH reduction and oxidative redox potential (ORP) reached the highest values (69.67% and 515 mV, respectively). Illumina HiSeq PE250 sequencing results show that the dominate microbial community members were Thiomonas (relative abundance 4.59~5.44%), which oxidize sulfur and ferrous iron, and Halothiobacillus (2.56~3.41%), which oxidizes sulfur. Thus, the acidic environment can promote microbial acidification and oxidation, which can help sludge dewatering. The presence of dominant sulfur oxidation bacteria is the essential reason for the deep dehydration of the bioleached sludge.
Obtaining, Evaluation, and Optimization of Doxycycline-Loaded Microparticles Intended for the Local Treatment of Infectious Arthritis
Authors: Marin Maria Minodora , Albu Kaya Mădălina Georgiana , Iovu Horia , Stavarache Cristina Elena , Chelaru Ciprian , Constantinescu Rodica Roxana , Dinu-Pîrvu Cristina-Elena , Ghica Mihaela Violeta
Published: October 2020

Compared to the classical systemic administration, the local drug release has some advantages, such as lack of systemic toxicity and associated side effects, increased patient compliance, and a low rate of bacterial resistance. Biopolymers are widely used to design sustained drug delivery systems and biomaterials for tissue engineering. Type II collagen is the indispensable component in articular cartilage and plays a critical role in the growth and proliferation process of chondrocytes. Thus, type II collagen has drawn more attention and interest in the treatment and research of the cartilage regeneration. The aim of this study was to obtain, characterize, and optimize the microcapsules formulation based on type II collagen, sodium alginate, and sodium carboxymethyl cellulose loaded with doxycycline as an antibiotic model drug that could be incorporated further in hydrogels to improve the localized therapy of septic arthritis. The new synthesized microcapsules were assessed by spectral (FT-IR), morphological (optical microscopy), and biological analysis (enzymatic biodegradation, antimicrobial activity). The size distribution of the obtained microcapsules was determined using optical microscopy. The drug encapsulation efficiency was also determined. To optimize the microcapsules’ composition, some physical-chemical and biological analyses were subjected to an optimization technique based on experimental design, response surface methodology, and the Taguchi technique, and the adequate formulations were selected. The results obtained recommend these new microcapsules as promising drug systems to be further incorporated in type II collagen hydrogels used for septic arthritis.
Ultrasonic Treatment Induced Fluoride Conversion Coating without Pores for High Corrosion Resistance of Mg Alloy
Authors: Li Sheng , Yi Laihua , Zhu Xiongxiang , Liu Tongfang
Published: October 2020

Fluoride conversion (MgF2) coating with facile preparation and good adhesion is promising to protect Mg alloy, but defects of pores in the coating lead to limited corrosion resistance. In this study, a compact and dense MgF2 coating was prepared by the combination of fluoride treatment and ultrasonic treatment. The ultrasonically treated MgF2 coating showed a compact and dense structure without pores at the frequency of 28 kHz. The chemical compositions of the coating were mainly composed of F and Mg elements. The corrosion potential of the ultrasonically treated Mg alloy shifted towards the noble direction in the electrochemical tests. The corrosion current density decreased due to the protectiveness of MgF2 coating without defects of pores or cracks. During immersion tests for 24 h, the ultrasonically treated Mg alloy exhibited the lowest H2 evolution (0.32 mL/cm2) and pH value (7.3), which confirmed the enhanced anti-corrosion ability of MgF2 coating. Hence, the ultrasonically treated fluoride coating had great potentials for their use in anti-corrosion applications of Mg alloy.
Modeling of Isocyanate Synthesis by the Thermal Decomposition of Carbamates
Authors: Dashkin Ratmir , Kolesnikov Georgii , Tsygankov Pavel , Lebedev Igor , Lebedev Artem , Menshutina Natalia , Ghafurov Khusrav , Bagomedov Abakar
Published: October 2020

The presented work is devoted to isocyanate synthesis by the thermal decomposition of carbamates model. The work describes the existing isocyanate-obtaining processes and the main problems in the study of isocyanate synthesis by the thermal decomposition of carbamates, which can be solved using mathematical and computer models. Experiments with carbamates of various structures were carried out. After processing the experimental data, the activation energy and the pre-exponential factor for isocyanate synthesis by the thermal decomposition of carbamates were determined. Then, a mathematical model of the reactor for the thermal decomposition of carbamates using the COMSOL Multiphysics software was developed. For this model, computational experiments under different conditions were carried out. It was shown that the calculation results correspond to the experimental ones, so the suggested model can be used in the design of the equipment for isocyanate synthesis by the thermal decomposition of carbamates.
Effect of 3D Representative Volume Element (RVE) Thickness on Stress and Strain Partitioning in Crystal Plasticity Simulations of Multi-Phase Materials
Authors: Qayyum Faisal , Chaudhry Aqeel Afzal , Guk Sergey , Schmidtchen Matthias , Kawalla Rudolf , Prahl Ulrich
Published: October 2020

Crystal plasticity simulations help to understand the local deformation behavior of multi-phase materials based on the microstructural attributes. The results of such simulations are mainly dependent on the Representative Volume Element (RVE) size and composition. The effect of RVE thickness on the changing global and local stress and strain is analyzed in this work for a test case of dual-phase steels in order to identify the minimal RVE thickness for obtaining consistent results. 100×100×100 voxel representative volume elements are constructed by varying grain size and random orientation distribution in DREAM-3D. The constructed RVEs are sliced in depth up to 1, 5, 10, 15, 20, 25, 30, 40, and 50 layers to construct different geometries with increasing thickness. Crystal plasticity model parameters for ferrite and martensite are taken from already published data and assigned to respective phases. Although the global stress/strain behavior of different RVEs is similar (<5% divergence), the local stress/strain partitioning in RVEs with varying thickness and grain size shows a considerable variation when statistically compared. It is concluded that two-dimensional (2D) RVEs can be used for crystal plasticity simulations when global deformation behavior is of interest. Whereas, it is necessary to consider three-dimensional (3D) RVEs, which have a specific thickness and number of grains for determining stabilized and more accurate local deformation behavior. This estimation will help researchers in optimizing the computation time for accurate mesoscale simulations.
Microstructural and Mechanical Characterization of Alloys
Authors: Sroka Marek , Golański Grzegorz
Published: October 2020

This Special Issue on “Microstructural and Mechanical Characterization of Alloys” features eight papers that cover the recent developments in alloys (engineering materials), methods of improvement of strength and cyclic properties of alloys, the stability of microstructure, the possible application of new (or improved) alloys, and the use of treatment for alloy improvement.
Alkali-Activated Hybrid Concrete Based on Fly Ash and Its Application in the Production of High-Class Structural Blocks
Authors: Rojas-Duque Oriana , Espinosa Lina Marcela , Robayo-Salazar Rafael A. , Mejía de Gutiérrez Ruby
Published: October 2020

This article reports the production and characterization of a hybrid concrete based on the alkaline activation of a fly ash (FA) of Colombian origin, which was added with 10% Portland cement (OPC) in order to promote the compressive strength development at room temperature. The alkali-activated hybrid cement FA/OPC 90/10 was classified as a low heat reaction cement (type LH), according to American Society of Testing Materials, ASTM C1157; the compressive strength was of 31.56 MPa and of 22.68 MPa (28 days) at the levels of paste and standard mortar, respectively, with an initial setting time of 93.3 min. From this binder, a hybrid concrete was produced and classified as a structural type, with a compressive strength of 23.16 MPa and a flexural modulus of rupture of 5.32 MPa, at 28 days of curing. The global warming potential index (GWP 100), based on life cycle analysis, was 35% lower than the reference concrete based on 100% OPC. Finally, its use was validated in the manufacture of a solid block-type construction element, which reached a compressive strength of 21.9 MPa at 28 days, exceeding by 40.6% the minimum strength value established by the Colombia Technical Standard, NTC 4026 (13 MPa) to be classified as high class structural blocks.
Diagnostic Accuracy of Biomarkers for Early-Onset Neonatal Bacterial Infections: Evaluation of Serum Procalcitonin Reference Curves
Authors: Go Hidetoshi , Nagano Nobuhiko , Katayama Daichi , Akimoto Takuya , Imaizumi Takayuki , Aoki Ryoji , Hijikata Midori , Seimiya Ayako , Kato Ryota , Okahashi Aya , Morioka Ichiro
Published: October 2020

To date, no clinical studies have compared the accuracy of serum procalcitonin (PCT) reference curves. We aimed to validate the diagnostic accuracy of previously reported serum PCT reference curves and to determine which biomarkers among a cut-off value over the 95th percentile in the serum PCT reference curve, white blood cell (WBC) count, and C-reactive protein (CRP) and immunoglobulin M (IgM) levels, have the highest diagnostic accuracy for early-onset neonatal bacterial infections. This retrospective cohort study assessed 16 preterm and 23 term infants with suspected bacterial infections within 72 h after birth. Each infant group was divided into two subgroups: confirmed- and non-infection. The diagnostic accuracy was determined using the Youden index. The reference curves by Fukuzumi et al. in preterm and term infants had the highest Youden indexes: 1.000 and 0.324, respectively. Among preterm infants, the Youden index for PCT was 1.000. Among term infants, the Youden index for a combination of PCT, CRP, and WBC and/or IgM was 1.000. In conclusion, a serum PCT level over the 95th percentile on the reference curve for preterm infants and a combination of PCT and CRP levels with WBC count and/or IgM levels for term infants provided sufficient diagnostic accuracy.
Literacy Teacher Educators Creating Space for Children’s Literature
Authors: Menna Lydia , Kosnik Clare , Dharamshi Pooja
Published: October 2020

This paper reports on a qualitative research study that examined how 10 literacy teacher educators (LTEs) utilized children’s literature to invite teacher trainees to critically engage with social issues, challenge their assumptions about literacy, and begin to develop the knowledge and dispositions to work alongside diverse learners (e.g., culturally, linguistically, socio-economically). The LTEs recognized that teacher trainees often entered their literacy courses with restricted conceptions of literacy and deficit assumptions about children from economically marginalized and/or culturally and linguistically diverse backgrounds. Within their courses, the LTEs positioned literacy as a multifaceted social practice, wherein access to a variety of representational resources facilitates the active construction of knowledge and identities. The LTEs modeled instructional strategies and designed assignments that encouraged teacher trainees to use children’s literature as a means to connect with issues relevant to the lives of young learners within contemporary classrooms. This research will be of interest to LTEs who endeavor to use children’s literature as a springboard to support teacher trainees to develop a self-reflective stance and a critical cultural consciousness.
Deep Learning-Based Localization for UWB Systems
Authors: Nguyen Doan Tan Anh , Lee Han-Gyeol , Jeong Eui-Rim , Lee Han Lim , Joung Jingon
Published: October 2020

Localization has been extensively studied owing to its huge potential in various areas, such as Internet of Things, 5G, and unmanned aerial vehicle services. Its wide applications include home automation, advanced production automation, and unmanned vehicle control. In this study, we propose a novel localization method that utilizes convolutional neural network (CNN) and ultra-wideband (UWB) signals. A localization problem is converted to a regression problem with the proposed CNN, in which the ranging and positioning phases are integrated. By integrating the ranging and positioning phases, the proposed CNN estimates the location of UWB transmitter directly without any additional step. To integrate both phases of localization, a simple-yet efficient input image generation method is proposed. In the proposed input image generation method, three oversampled two-dimensional input images are generated from the three received UWB signals and they are provided to the designed CNN through the three channels, which are represented by red-, green-, and blue-color channels, respectively. The proposed CNN-based localization system then estimates the location of the UWB transmitter directly using the three-channel image as an input of the CNN. Simulation results verify that the proposed CNN-based localization method outperforms the traditional threshold-based and existing CNN-based methods. Also, it is observed that the proposed method performs well under an asymmetric environment, unlike the existing method.
Improving Deep Learning-Based UWB LOS/NLOS Identification with Transfer Learning: An Empirical Approach
Authors: Park JiWoong , Nam SungChan , Choi HongBeom , Ko YoungEun , Ko Young-Bae
Published: October 2020

This paper presents an improved ultra-wideband (UWB) line of sight (LOS)/non-line of sight (NLOS) identification scheme based on a hybrid method of deep learning and transfer learning. Previous studies have limitations, in that the classification accuracy significantly decreases in an unknown place. To solve this problem, we propose a transfer learning-based NLOS identification method for classifying the NLOS conditions of the UWB signal in an unmeasured environment. Both the multilayer perceptron and convolutional neural network (CNN) are introduced as classifiers for NLOS conditions. We evaluate the proposed scheme by conducting experiments in both measured and unmeasured environments. Channel data were measured using a Decawave EVK1000 in two similar indoor office environments. In the unmeasured environment, the existing CNN method showed an accuracy of approximately 44%, but when the proposed scheme was applied to the CNN, it showed an accuracy of up to 98%. The training time of the proposed scheme was measured to be approximately 48 times faster than that of the existing CNN. When comparing the proposed scheme with learning a new CNN in an unmeasured environment, the proposed scheme demonstrated an approximately 10% higher accuracy and approximately five times faster training time.
A Fast Deep Learning Method for Security Vulnerability Study of XOR PUFs
Authors: Mursi Khalid T. , Thapaliya Bipana , Zhuang Yu , Aseeri Ahmad O. , Alkatheiri Mohammed Saeed
Published: October 2020

Physical unclonable functions (PUF) are emerging as a promising alternative to traditional cryptographic protocols for IoT authentication. XOR Arbiter PUFs (XPUFs), a group of well-studied PUFs, are found to be secure against machine learning (ML) attacks if the XOR gate is large enough, as both the number of CRPs and the computational time required for modeling n-XPUF increases fast with respect to n, the number of component arbiter PUFs. In this paper, we present a neural network-based method that can successfully attack XPUFs with significantly fewer CRPs and shorter learning time when compared with existing ML attack methods. Specifically, the experimental study in this paper shows that our new method can break the 64-bit 9-XPUF within ten minutes of learning time for all of the tested samples and runs, with magnitudes faster than the fastest existing ML attack method, which takes over 1.5 days of parallel computing time on 16 cores.
Attention Collaborative Autoencoder for Explicit Recommender Systems
Authors: Chen Shuo , Wu Min
Published: October 2020

Recently, various deep learning-based models have been applied in the study of recommender systems. Some researches have combined the classic collaborative filtering method with deep learning frameworks in order to obtain more accurate recommendations. However, these models either add additional features, but still recommend in the original linear manner, or only extract the global latent factors of the rating matrices in a non-linear way without considering some local special relationships. In this paper, we propose a deep learning framework for explicit recommender systems, named Attention Collaborative Autoencoder (ACAE). Based on the denoising autoencoder, our model can extract the global latent factors in a non-linear fashion from the sparse rating matrices. In ACAE, attention units are introduced during back propagation, enabling discovering potential relationships between users and items in the neighborhood, which makes the model obtain better results in the rating prediction tasks. In addition, we propose how to optimize the training process of the model by proposing a new loss function. Experiments on two public datasets demonstrate the effectiveness of ACAE and its outperformance of competitive baselines.
greenMAC Protocol: A Q-Learning-Based Mechanism to Enhance Channel Reliability for WLAN Energy Savings
Authors: Ali Rashid , Sohail Muhammad , Almagrabi Alaa Omran , Musaddiq Arslan , Kim Byung-Seo
Published: October 2020

We have seen a promising acceptance of wireless local area networks (WLANs) in our day-to-day communication devices, such as handheld smartphones, tablets, and laptops. Energy preservation plays a vital role in WLAN communication networks. The efficient use of energy remains one of the most substantial challenges to WLAN devices. Several approaches have been proposed by the industrial and institutional researchers to save energy and reduce the overall power consumption of WLAN devices focusing on static/adaptive energy saving methods. However, most of the approaches save energy at the cost of throughput degradation due to either increased sleep-time or reduced number of transmissions. In this paper, we recognize the potentials of reinforcement learning (RL) techniques, such as the Q-learning (QL) model, to enhance the WLAN’s channel reliability for energy saving. QL is one of the RL techniques, which utilizes the accumulated reward of the actions performed in the state-action model. We propose a QL-based energy-saving MAC protocol, named greenMAC protocol. The proposed greenMAC protocol reduces the energy consumption by utilizing accumulated reward value to optimize the channel reliability, which results in reduced channel collision probability of the network. We assess the degrees of channel congestion in collision probability as a reward function for our QL-based greenMAC protocol. The comparative results show that greenMAC protocol achieves enhanced system throughput performance with additional energy savings compared to existing energy-saving mechanisms in WLANs.
Physical Experiment and Numerical Modeling on the Failure Mechanism of Gob-Side Entry Driven in Thick Coal Seam
Authors: Shi Xinshuai , Jing Hongwen , Zhao Zhenlong , Gao Yuan , Zhang Yuanchao , Bu Ruodi
Published: October 2020

In this paper, a combination of physical model tests and numerical simulations were carried out to explore the overlying strata movement laws, failure mechanism, and cracks evolution of the gob-side entry driven in a thick coal seam. The physical experimental results indicated that the hanging cantilever beam was easily developed above the coal pillar after mining out the 2101 panel, resulting in a larger and stronger stress concentration. The overburden loads acting on the coal pillar can be greatly released after the hanging roof strata were cut down with an 18 m cutting line. Additionally, we adopted Universal Discrete Element Code (UDEC) software to investigate the deformation and crack evolution mechanism of the gob-side entry under different conditions. The primary-supported roadway underwent severe deformation, filling with a great quantity of tensile and shear cracks to the inner coal pillar. Both the physical and numerical results proved that the optimized-support parameters combined with roof-cutting measures could effectively guarantee the stability of the gob-side entry. This research can provide valuable guidance for the stability control of the gob-side entry in mines under similar conditions.
An Analysis of the Impact of Forest Policy on Rural Areas of Chile
Authors: Cerda Raúl , Gallardo-Cobos Rosa , Sánchez-Zamora Pedro
Published: October 2020

The relationship between the forest sector and the well-being of people that depend on it for their economic livelihoods in rural areas is of strong interest in forest policy. In this sense, Chile has developed a forest policy that has had positive impacts, particularly on economic and productive aspects, but also negative impacts, such as the reduction of natural forest area, biodiversity, and provision of ecosystem services, as well as the increase in social conflicts and land abandonment. However, there are few studies that have evaluated the impacts of forest policy on rural population and development of the territory. Therefore, the objective of this research is to evaluate the impacts of Chilean forest policy on rural communities, particularly in terms of demographic variables and indicators of community well-being. The study area corresponds to the Bio Bio and Ñuble Regions (Chile), and the analysis includes productive, demographic, socioeconomic, and educational characteristics of population. The results show that the forestry policy implemented was able to generate a significant increase in the proportion of forest area. However, when this increase is mainly of the type of exotic forest plantations, it is associated with a demographic and socio-economic detriment of the population in some counties of the study area.
Key Community Assembly Processes Switch between Scales in Shaping Beta Diversity in Two Primary Forests, Southwest China
Authors: Asefa Mengesha , Wen Han-Dong , Cao Min , Hu Yue-Hua
Published: October 2020

Environmental and dispersal-based processes have been widely investigated for the understanding of community assembly. However, the relative importance of these ecological processes across spatial scales, life history stages and forest types needs to be largely studied. We test the variability of ecological processes in shaping tree community composition across life stages and spatial scales, and in particular, the hypothesis that dispersal limitation dominates at smaller scales and early life stages, but environmental filtering at larger scales and later life stages. We used spatially explicit point process models to estimate the relative importance of environmental and dispersal processes and their combined effect on beta diversity across spatial scales and life stages in tropical and subtropical forests. These models fit the observed species distribution pattern and generated realizations of the fitted models for each species. We found that the importance of environmental and dispersal processes did not shift with life stages or vegetation types, but did with spatial scales. Dispersal provided the best explanation of large-scale patterns, but dispersal combined with environmental selection was superior for small-scale patterns. In conclusion, we confirm the importance of spatial scale for the effects and identification of community assembly mechanisms. Our results also suggest that the importance of both dispersal and environmental processes for community assembly could be pervasive across life stages and vegetation types. The generality of these findings should be tested further in different vegetation types and life stages to assess whether specific ecological processes have consistent effects on community structure across life stages and vegetation types.
Interactions between Phytophthora cactorum, Armillaria gallica and Betula pendula Roth. Seedlings Subjected to Defoliation
Authors: Nowakowska Justyna Anna , Stocki Marcin , Stocka Natalia , Ślusarski Sławomir , Tkaczyk Miłosz , Caetano João Maria , Tulik Mirela , Hsiang Tom , Oszako Tomasz
Published: October 2020

The purpose of this study was to better understand the interactive impact of two soil-borne pathogens, Phytophthora cactorum and Armillaria gallica, on seedlings of silver birch (Betula pendula Roth.) subjected to stress caused by mechanical defoliation, simulating primary insect feeding. This is the first experimental confirmation of silver birch seedling root damage (and in consequence shoot mortality) caused by the additive effect of defoliation stress and P. cactorum inoculation via soil. However, the most severe damage to roots occurred after A. gallica inoculation. One year after treatments, chlorophyll fluorescence measurement, and gas chromatography coupled with mass spectrometry (GC-MS) were used to analyze the photosynthetic activity in leaves, the volatile organic compounds (VOCs) emitted by the birch leaves, and chemical compounds from the roots. The cumulative effect of the two pathogens and partial defoliation reduced photosynthetic activity, suggesting dysfunction of photosystem PSII due to the applied stresses. In summary, it seems that the main differences in photosynthetic performance could be attributed to Armillaria infection. The birch leaves in seedlings exposed to 50% defoliation, and inoculation with P.cactorum and A. gallica, emitted more aromatic carbonyls and alcohols, as well as half as much aliphatic esters, compared to controls. In infected birch roots, the production of phenols, triterpenes, and fatty alcohols increased, but fatty acids decreased. Higher levels of aromatic carbonyls and alcohols in leaves, as well as phenolic compounds in the roots of stressed birches (compared to control) suggest an activation of plant systemic acquired resistance (SAR).