bluuebunny/crossref_metadata_2025 huggingface dataset:
Autophagy Roles in Genome Maintenance
Authors: Ambrosio Susanna , Majello Barbara
Published: July 2020

In recent years, a considerable correlation has emerged between autophagy and genome integrity. A range of mechanisms appear to be involved where autophagy participates in preventing genomic instability, as well as in DNA damage response and cell fate decision. These initial findings have attracted particular attention in the context of malignancy; however, the crosstalk between autophagy and DNA damage response is just beginning to be explored and key questions remain that need to be addressed, to move this area of research forward and illuminate the overall consequence of targeting this process in human therapies. Here we present current knowledge on the complex crosstalk between autophagy and genome integrity and discuss its implications for cancer cell survival and response to therapy.
Immunophenotypes Based on the Tumor Immune Microenvironment Allow for Unsupervised Penile Cancer Patient Stratification
Authors: Chu Chengbiao , Yao Kai , Lu Jiangli , Zhang Yijun , Chen Keming , Lu Jiabin , Zhang Chris Zhiyi , Cao Yun
Published: July 2020

The tumor immune microenvironment (TIME) plays an important role in penile squamous cell carcinoma (peSCC) pathogenesis. Here, the immunophenotype of the TIME in peSCC was determined by integrating the expression patterns of immune checkpoints (programmed cell death-1 (PD-1)/programmed cell death ligand-1 (PD-L1), cytotoxic T lymphocyte antigen 4 (CTLA-4), and Siglec-15) and the components of tumor-infiltrating lymphocytes, including CD8+ or Granzyme B+ T cells, FOXP3+ regulatory T cells, and CD68+ or CD206+ macrophages, in 178 patients. A high density of Granzyme B, FOXP3, CD68, CD206, PD-1, and CTLA-4 was associated with better disease-specific survival (DSS). The patients with diffuse PD-L1 tumor cell expression had worse prognoses than those with marginal or negative PD-L1 expression. Four immunophenotypes were identified by unsupervised clustering analysis, based on certain immune markers, which were associated with DSS and lymph node metastasis (LNM) in peSCC. There was no significant relationship between the immunophenotypes and high-risk human papillomavirus (hrHPV) infection. However, the hrHPV–positive peSCC exhibited a higher density of stromal Granzyme B and intratumoral PD-1 than the hrHPV–negative tumors (p = 0.049 and 0.002, respectively). In conclusion, the immunophenotypes of peSCC were of great value in predicting LNM and prognosis, and may provide support for clinical stratification management and immunotherapy intervention.
Comprehensive Constitutional Genetic and Epigenetic Characterization of Lynch-Like Individuals
Authors: Dámaso Estela , González-Acosta Maribel , Vargas-Parra Gardenia , Navarro Matilde , Balmaña Judith , Ramon y Cajal Teresa , Tuset Noemí , Thompson Bryony A. , Marín Fátima , Fernández Anna , Gómez Carolina , Velasco Àngela , Solanes Ares , Iglesias Sílvia , Urgel Gisela , López Consol , del Valle Jesús , Campos Olga , Santacana Maria , Matias-Guiu Xavier , Lázaro Conxi , Valle Laura , Brunet Joan , Pineda Marta , Capellá Gabriel
Published: July 2020

The causal mechanism for cancer predisposition in Lynch-like syndrome (LLS) remains unknown. Our aim was to elucidate the constitutional basis of mismatch repair (MMR) deficiency in LLS patients throughout a comprehensive (epi)genetic analysis. One hundred and fifteen LLS patients harboring MMR-deficient tumors and no germline MMR mutations were included. Mutational analysis of 26 colorectal cancer (CRC)-associated genes was performed. Pathogenicity of MMR variants was assessed by splicing and multifactorial likelihood analyses. Genome-wide methylome analysis was performed by the Infinium Human Methylation 450K Bead Chip. The multigene panel analysis revealed the presence of two MMR gene truncating mutations not previously found. Of a total of 15 additional MMR variants identified, five -present in 6 unrelated individuals- were reclassified as pathogenic. In addition, 13 predicted deleterious variants in other CRC-predisposing genes were found in 12 probands. Methylome analysis detected one constitutional MLH1 epimutation, but no additional differentially methylated regions were identified in LLS compared to LS patients or cancer-free individuals. In conclusion, the use of an ad-hoc designed gene panel combined with pathogenicity assessment of variants allowed the identification of deleterious MMR mutations as well as new LLS candidate causal genes. Constitutional epimutations in non-LS-associated genes are not responsible for LLS.
Epitope Mapping and Computational Analysis of Anti-HPV16 E6 and E7 Antibodies in Single-Chain Format for Clinical Development as Antitumor Drugs
Authors: Amici Carla , Donà Maria Gabriella , Chirullo Barbara , Di Bonito Paola , Accardi Luisa
Published: July 2020

Human Papillomavirus 16-associated cancer, affecting primarily the uterine cervix but, increasingly, other body districts, including the head–neck area, will long be a public health problem, despite there being a vaccine. Since the virus oncogenic activity is fully ascribed to the viral E6 and E7 oncoproteins, one of the therapeutic approaches for HPV16 cancer is based on specific antibodies in single-chain format targeting the E6/E7 activity. We analyzed the Complementarity Determining Regions, repositories of antigen-binding activity, of four anti-HPV16 E6 and -HPV16 E7 scFvs, to highlight possible conformity to biophysical properties, recognized to be advantageous for therapeutic use. By epitope mapping, using E7 mutants with amino acid deletions or variations, we investigated differences among the anti-16E7 scFvs in terms of antigen-binding capacity. We also performed computational analyses to determine whether length, total net charge, surface hydrophobicity, polarity and charge distribution conformed well to those of the antibodies that had already reached clinical use, through the application of developability guidelines derived from recent literature on clinical-stage antibodies, and the Therapeutic Antibodies Profiler software. Overall, our findings show that the scFvs investigated may represent valid candidates to be developed as therapeutic molecules for clinical use, and highlight characteristics that could be improved by molecular engineering.
ALK-Brain Prognostic Index—Preliminary Study of a Prognostic Tool for Patients with ALK-Rearranged, Non-small Cell Lung Cancer and Brain Metastases
Authors: Tsakonas Georgios , Kamali Caroline , De Petris Luigi , Friesland Signe , Lewensohn Rolf , Ekman Simon
Published: July 2020

Background: Disease-specific Graded Prognostic Assessment (DS-GPA) is the most validated prognostic tool for patients with brain metastasized lung cancer. The Lung-molGPA scoring system was recently introduced for oncogenic-driven brain metastasized lung cancer, but has not yet been validated in cohorts including only ALK-translocated tumors. Methods: We designed a retrospective cohort study consisting of 44 patients with brain metastasized ALK-positive, non-small cell lung cancer (NSCLC) who were treated between January 2009 and November 2019 at Karolinska University Hospital in Stockholm, Sweden. Information about demographics and clinicopathological parameters were collected. Predictors of overall survival (OS) were identified by Cox regression analyses. A bootstrap validation with 1000 samples was performed in order to compare the different prognostic scores. Results: The variables found to independently influence OS in the multivariate analysis, i.e., PS, sex and brain metastases at diagnosis, were used as prognostic variables in our new prognostic index (ALK-BPI). Patients were divided into two prognostic groups. The median OS was 65.7 months for the good prognostic group and 22.7 months for the poor prognostic group (p = 0.0068). In the univariate analysis of the different prognostic scores, ALK-BPI performed better than the others (HR = 3.6; 95% CI: 1.3–9.9). The mean C-statistics of the different prognostic scores were compared to each other, and no significant difference was observed. Conclusion: We propose the ALK-BPI score as a new prognostic tool that can easily be applied for ALK-positive lung cancer patients with brain metastases in daily clinical practice, as it has at least the same prognostic value as Lung-molGPA.
Risk of Liver Cirrhosis and Hepatocellular Carcinoma after Fontan Operation: A Need for Surveillance
Authors: Yoon Jun Sik , Lee Dong Ho , Cho Eun Ju , Song Mi Kyoung , Choi Young Hun , Kim Gi Beom , Lee Yun Bin , Lee Jeong-Hoon , Yu Su Jong , Kim Haeryoung , Kim Yoon Jun , Yoon Jung-Hwan , Bae Eun Jung
Published: July 2020

Liver cirrhosis and hepatocellular carcinoma (HCC) are serious late complications that can occur after the Fontan procedure. This study aimed to investigate the cumulative incidence of cirrhosis and HCC and to identify specific features distinguishing HCC from benign arterial-phase hyperenhancing (APHE) nodules that developed after the Fontan operation. We retrospectively enrolled 313 post-Fontan patients who had been followed for more than 5 years and had undergone ultrasound or computed tomography (CT) of the liver between January 2000 and August 2018. Cirrhosis was diagnosed radiologically. The estimated cumulative incidence rates of cirrhosis at 5, 10, 20, and 30 years after the Fontan operation were 1.3%, 9.2%, 56.6%, and 97.9%, respectively. Multiphasic CT revealed that 18 patients had APHE nodules that were ≥1 cm in size and showed washout in the portal venous phase (PVP)/delayed phase, which met current noninvasive HCC diagnosis criteria. Among them, only seven patients (38.9%, 7/18) were diagnosed with HCC. After cirrhosis developed, the annual incidence of HCC was 1.04%. The appearance of washout in the PVP (p = 0.006), long time elapsed since the initial Fontan operation (p = 0.04), large nodule size (p = 0.03), and elevated serum α-fetoprotein (AFP) level (p < 0.001) were significantly associated with HCC. In conclusion, cirrhosis is a frequent late complication after Fontan operation, especially after 10 years, and HCC is not a rare complication after cirrhosis development. Diagnosis of HCC should not be based solely on the current imaging criteria, and washout on PVP and clinical features might be helpful to differentiate HCC nodules from benign APHE nodules.
Improved Diagnostic Imaging of Brain Tumors by Multimodal Microscopy and Deep Learning
Authors: Gesperger Johanna , Lichtenegger Antonia , Roetzer Thomas , Salas Matthias , Eugui Pablo , Harper Danielle J. , Merkle Conrad W. , Augustin Marco , Kiesel Barbara , Mercea Petra A. , Widhalm Georg , Baumann Bernhard , Woehrer Adelheid
Published: July 2020

Fluorescence-guided surgery is a state-of-the-art approach for intraoperative imaging during neurosurgical removal of tumor tissue. While the visualization of high-grade gliomas is reliable, lower grade glioma often lack visible fluorescence signals. Here, we present a hybrid prototype combining visible light optical coherence microscopy (OCM) and high-resolution fluorescence imaging for assessment of brain tumor samples acquired by 5-aminolevulinic acid (5-ALA) fluorescence-guided surgery. OCM provides high-resolution information of the inherent tissue scattering and absorption properties of tissue. We here explore quantitative attenuation coefficients derived from volumetric OCM intensity data and quantitative high-resolution 5-ALA fluorescence as potential biomarkers for tissue malignancy including otherwise difficult-to-assess low-grade glioma. We validate our findings against the gold standard histology and use attenuation and fluorescence intensity measures to differentiate between tumor core, infiltrative zone and adjacent brain tissue. Using large field-of-view scans acquired by a near-infrared swept-source optical coherence tomography setup, we provide initial assessments of tumor heterogeneity. Finally, we use cross-sectional OCM images to train a convolutional neural network that discriminates tumor from non-tumor tissue with an accuracy of 97%. Collectively, the present hybrid approach offers potential to translate into an in vivo imaging setup for substantially improved intraoperative guidance of brain tumor surgeries.
Aetiology of Myeloproliferative Neoplasms
Authors: McMullin Mary Frances , Anderson Lesley Ann
Published: July 2020

Myeloproliferative neoplasms (MPNs) have estimated annual incidence rates for polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis of 0.84, 1.03, and 0.47 per 100,000. Prevalence is much higher, particularly for PV and ET, as mortality rates are relatively low. Patients are often concerned about why they developed an MPN and epidemiological studies enable the identification of potential causative factors. Previous work in small heterogeneous studies has identified a variety of risk factors associated with MPNs including family history of MPN, autoimmune conditions, some occupational exposures, and blood donation. At a population level, germline predisposition factors in various populations have been associated with MPNs. The pilot MOSAICC (Myeloproliferative Neoplasm: An In-depth Case-Control) study is one of the largest epidemiological studies in MPN ever carried out to date. It demonstrated the most effective methods for carrying out a significant epidemiological study in this patient group including the best way of recruiting controls, as well as how to evaluate occupational and lifestyle exposures, evaluate symptoms, and collect biological samples. Significant results linked to MPNs in the pilot study of 106 patients included smoking, obesity, and childhood socioeconomic status. The methodology is now in place for a much larger ongoing MOSAICC study which should provide further insight into the potential causes of MPNs.
The Nucleolus and PARP1 in Cancer Biology
Authors: Engbrecht Marina , Mangerich Aswin
Published: July 2020

The nucleolus has been known for a long time to fulfill crucial functions in ribosome biogenesis, of which cancer cells can become addicted to in order to produce sufficient amounts of proteins for cell proliferation. Recently, the nucleolus has emerged as a central regulatory hub in many other cancer-relevant processes, including stress sensing, DNA damage response, cell cycle control, and proteostasis. This fostered the idea that nucleolar processes can be exploited in cancer therapy. Interestingly, a significant proportion of poly(ADP-ribose) polymerase 1 (PARP1) molecules are localized in the nucleolus and PARP1 also plays crucial roles in many processes that are important in cancer biology, including genome maintenance, replication, transcription, and chromatin remodeling. Furthermore, during the last years, PARP1 came into focus in oncology since it represents a promising target of pharmacological PARP inhibitors in various types of cancers. Here, we provide an overview of our current understanding on the role of PARP1 in nucleolar functions and discuss potential implications in cancer biology and therapy.
Latest Developed Strategies to Minimize the Off-Target Effects in CRISPR-Cas-Mediated Genome Editing
Authors: Naeem Muhammad , Majeed Saman , Hoque Mubasher Zahir , Ahmad Irshad
Published: July 2020

Gene editing that makes target gene modification in the genome by deletion or addition has revolutionized the era of biomedicine. Clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 emerged as a substantial tool due to its simplicity in use, less cost and extraordinary efficiency than the conventional gene-editing tools, including zinc finger nucleases (ZFNs) and Transcription activator-like effector nucleases (TALENs). However, potential off-target activities are crucial shortcomings in the CRISPR system. Numerous types of approaches have been developed to reduce off-target effects. Here, we review several latest approaches to reduce the off-target effects, including biased or unbiased off-target detection, cytosine or adenine base editors, prime editing, dCas9, Cas9 paired nickase, ribonucleoprotein (RNP) delivery and truncated gRNAs. This review article provides extensive information to cautiously interpret off-target effects to assist the basic and clinical applications in biomedicine.
Identification of Novel Molecular Markers of Human Th17 Cells
Authors: Sałkowska Anna , Karaś Kaja , Karwaciak Iwona , Walczak-Drzewiecka Aurelia , Krawczyk Mariusz , Sobalska-Kwapis Marta , Dastych Jarosław , Ratajewski Marcin
Published: July 2020

Th17 cells are important players in host defense against pathogens such as Staphylococcus aureus, Candida albicans, and Bacillus anthracis. Th17 cell-mediated inflammation, under certain conditions in which balance in the immune system is disrupted, is the underlying pathogenic mechanism of certain autoimmune disorders, e.g., rheumatoid arthritis, Graves’ disease, multiple sclerosis, and psoriasis. In the present study, using transcriptomic profiling, we selected genes and analyzed the expression of these genes to find potential novel markers of Th17 lymphocytes. We found that APOD (apolipoprotein D); C1QL1 (complement component 1, Q subcomponent-like protein 1); and CTSL (cathepsin L) are expressed at significantly higher mRNA and protein levels in Th17 cells than in the Th1, Th2, and Treg subtypes. Interestingly, these genes and the proteins they encode are well associated with the function of Th17 cells, as these cells produce inflammation, which is linked with atherosclerosis and angiogenesis. Furthermore, we found that high expression of these genes in Th17 cells is associated with the acetylation of H2BK12 within their promoters. Thus, our results provide new information regarding this cell type. Based on these results, we also hope to better identify pathological conditions of clinical significance caused by Th17 cells.
Neurovascular Inflammaging in Health and Disease
Authors: Mészáros Ádám , Molnár Kinga , Nógrádi Bernát , Hernádi Zsófia , Nyúl-Tóth Ádám , Wilhelm Imola , Krizbai István A.
Published: July 2020

Aging is characterized by a chronic low-grade sterile inflammation dubbed as inflammaging, which in part originates from accumulating cellular debris. These, acting as danger signals with many intrinsic factors such as cytokines, are sensed by a network of pattern recognition receptors and other cognate receptors, leading to the activation of inflammasomes. Due to the inflammasome activity-dependent increase in the levels of pro-inflammatory interleukins (IL-1β, IL-18), inflammation is initiated, resulting in tissue injury in various organs, the brain and the spinal cord included. Similarly, in age-related diseases of the central nervous system (CNS), inflammasome activation is a prominent moment, in which cells of the neurovascular unit occupy a significant position. In this review, we discuss the inflammatory changes in normal aging and summarize the current knowledge on the role of inflammasomes and contributing mechanisms in common CNS diseases, namely Alzheimer’s disease, Parkinson’s disease, amyotrophic lateral sclerosis and stroke, all of which occur more frequently with aging.
Cell-Type Targeted NF-kappaB Inhibition for the Treatment of Inflammatory Diseases
Authors: Sehnert Bettina , Burkhardt Harald , Dübel Stefan , Voll Reinhard E.
Published: July 2020

Deregulated NF-k activation is not only involved in cancer but also contributes to the pathogenesis of chronic inflammatory diseases like rheumatoid arthritis (RA) and multiple sclerosis (MS). Ideally, therapeutic NF-KappaB inhibition should only take place in those cell types that are involved in disease pathogenesis to maintain physiological cell functions in all other cells. In contrast, unselective NF-kappaB inhibition in all cells results in multiple adverse effects, a major hindrance in drug development. Hitherto, various substances exist to inhibit different steps of NF-kappaB signaling. However, powerful tools for cell-type specific NF-kappaB inhibition are not yet established. Here, we review the role of NF-kappaB in inflammatory diseases, current strategies for drug delivery and NF-kappaB inhibition and point out the “sneaking ligand” approach. Sneaking ligand fusion proteins (SLFPs) are recombinant proteins with modular architecture consisting of three domains. The prototype SLC1 binds specifically to the activated endothelium and blocks canonical NF-kappaB activation. In vivo, SLC1 attenuated clinical and histological signs of experimental arthritides. The SLFP architecture allows an easy exchange of binding and effector domains and represents an attractive approach to study disease-relevant biological targets in a broad range of diseases. In vivo, SLFP treatment might increase therapeutic efficacy while minimizing adverse effects.
Microstructure and Wear-Resistant Properties of Ni80Al20-MoS2 Composite Coating on Sled Track Slippers
Authors: Wang Weihua , Xie Faqin , Wu Xiangqing , Zhu Zheng , Wang Shaoqing , Lv Tao
Published: July 2020

In order to increase the surface hardness and wear-resistance property of sled track slippers, a Ni80Al20-MoS2 composite coating was fabricated on the surface of a stainless steel 0Cr18Ni9Ti sled track slipper via atmospheric spray and hot dipping. The microstructure, composition and surface hardness of coatings under different spraying powers were characterized and measured. The wear-resistant properties of the slipper substrate and the coating were also checked. The results showed that the higher the spraying power was, the greater the smoothness, density and hardness was of the Ni80Al20 coating, while the thickness initially increased and then decreased. When the spraying power was 18 kW, the thickness was 342.5 μm, the surface hardness was 304.1 Hv0.2, and the coating was composed of Ni, Al, Ni3Al, NiAl and a little Al2O3. The friction coefficient of the slipper substrate against GCr15 balls at room temperature in air was 0.7, while the coated substrate with MoS2 lubrication film was 0.3 and the volume wear rate declined by 1/5. The friction coefficient of the Ni80Al20 coating was 0.5 and the Ni80Al20-MoS2 composite coating was 0.15, while the volume wear rate declined by 1/4 and 1/3.
Tamper and Clone-Resistant Authentication Scheme for Medical Image Systems
Authors: Tayachi Mayssa , Mulhem Saleh , Adi Wael , Nana Laurent , Pascu Anca , Benzarti Faouzi
Published: July 2020

Telemedicine applications are more and more used due to the rapid development of digital imaging and information and communication technologies. Medical information which include digital medical images and patient’s information are extracted and transmitted over insecure networks for clinical diagnosis and treatments. Digital watermarking is one of the main approaches used to ensure the security of medical images. Nevertheless, in some cases, the only use of digital watermarking is not sufficient to reach a high level of security. Indeed, the watermark could carry essential patient information and needs to be protected. In such cases, cryptography may be used to protect the watermark and to improve the overall secured management in the medical environment. In this paper, we propose a clone-resistant watermarking approach combining a difference expansion watermarking technique with a cryptographic technique based on secret keys generated by a clone-resistant device called Secret Unknown Ciphers (SUCs). The use of SUCs to sign the watermark enforces the security of medical images during their transfer and storage. Experimental results show that the system provides a high level of security against various forms of attacks.
Influence of Nonlocality on Transmittance and Reflectance of Hyperbolic Metamaterials
Authors: Janaszek Bartosz , Kieliszczyk Marcin , Tyszka-Zawadzka Anna , Szczepański Paweł
Published: July 2020

In this paper we investigate transmittance and reflectance spectra of multilayer hyperbolic metamaterials in the presence of strong spatial dispersion. Our analysis revealed a number of intriguing optical phenomena, which cannot be predicted with the local response approximation, such as total reflectance for small angles of incidence or multiple transmittance peaks of resonant character (instead of the respective local counterparts, where almost complete transparency is predicted for small angles of incidence and the broad-angle transparency can be observed within a range of larger angles of incidence). We believe that the observed effects may serve as a working principle in a number of new potential applications, such as spatial filtering, biosensing, or beam steering.
A Self-Assembled Hetero-Bimetallic [Ni(II)-Sm(III)] Coordination Polymer Constructed from a Salamo-Like Ligand and 4,4′-Bipyridine: Synthesis, Structural Characterization, and Properties
Authors: Li Ruo-Yan , An Xiao-Xin , Wang Ji-Fa , Mu Hao-Ran , Zhang You-Peng , Zhang Yang , Dong Wen-Kui
Published: July 2020

An unusual self-assembled hetero-bimetallic [Ni(II)-Sm(III)] coordination polymer, [Ni(L)Sm(NO3)3(4,4′-bipy)]n, is prepared through a hexadentate chelating ligand 2,2′-[1,2-ethylenedioxybis(nitrilomethylidyne)]diphenol (H2L). The Ni(II)-Sm(III) coordination polymer is validated through elemental analyses, Fourier-transform infrared and UV-Visible spectroscopies, and X-ray single-crystal diffraction. The Ni(II) atom forms a twisted six-coordinated octahedron, and the Sm(III) atom is ten-coordinated, adopting a twisted bicapped square antiprism. An infinite three-dimensional-layer supramolecular structure is obtained through extensive π···π stacking and intermolecular hydrogen bonding interactions. The polymer has a good antibacterial effect against Staphylococcus aureus.
Properties of N-Type GaN Thin Film with Si-Ti Codoping on a Glass Substrate
Authors: Liu Wei-Sheng , Chang Yu-Lin , Tan Chun-Yuan , Tsai Cheng-Ting , Kuo Hsing-Chun
Published: July 2020

In this study, n-type gallium nitride (GaN) films were fabricated by a silicon–titanium (Si-Ti) codoping sputtering technique with a zinc oxide (ZnO) buffer layer on amorphous glass substrates with different post-growth annealing temperatures for optimizing the GaN crystal quality. Si-Ti-codoped n-type GaN films that were thermally annealed at 400 °C had a low thin-film resistivity of 2.6 × 10−1 Ω-cm and a high electron concentration of 6.65 × 1019 cm−3, as determined through Hall measurement. X-ray diffraction (XRD) results revealed a high (002) XRD intensity with a narrow spectral line and a full width at half maximum (FWHM) value that indicated the superior crystal growth of a hexagonal structure of the GaN thin films. In addition, photoluminescence measurement results demonstrated a near-band-edge emission at 365 nm, indicating the crystal growth of GaN thin films on glass substrates. The Burstein–Moss effect was observed in the Tauc plot results, indicating that the Fermi level inside the conduction band moves upward and thus improves the n-type properties of the GaN thin film. X-ray photoelectron spectroscopy measurement results revealed that all atoms doped into the GaN film are present and that both Si and Ti atoms bond with N atoms.
In Situ Imaging of Domain Structure Evolution in LaBGeO5 Single Crystals
Authors: Akhmatkhanov Andrey , Plashinnov Constantine , Nebogatikov Maxim , Milov Evgenii , Shnaidshtein Ilya , Shur Vladimir
Published: July 2020

LaBGeO5 (LBGO) crystals are unique ferroelectric materials for manufacturing highly efficient UV laser sources based on frequency conversion. This is due to their low cut-off wavelength, high nonlinear-optical coefficients, and non-hygroscopicity. Periodical poling requires a deep study of domain kinetics in these crystals. Domain imaging by Cherenkov second harmonic generation microscopy was used to reveal the main processes of domain structure evolution: (1) growth and merging of isolated domains, (2) growth of stripe domains formed on the artificial linear surface defects, and (3) domain shrinkage. In a low field, growth of triangular domains and fast shape recovery after merging were observed, while in a high field, the circular domains grew independently after merging. The revealed essential wall motion anisotropy decreased with the field. The anisotropy led to significant shape transformations during domain shrinkage in low field. The formation of short-lived triangular domains rotated by 180 degrees with respect to the growing isolated domains was observed. The obtained results were explained within the kinetic approach to domain structure evolution based on the analogy between the growth of crystals and ferroelectric domains, taking into account the gradual transition from determined nucleation in low field to the stochastic one in high field.
Growth and Scintillation Properties of Directionally Solidified Ce:LaBr3/AEBr2 (AE = Mg, Ca, Sr, Ba) Eutectic System
Authors: Kim Kyoung Jin , Furuya Yuki , Kamada Kei , Murakami Rikito , Kochurikhin Vladimir V. , Yoshino Masao , Chiba Hiroyuki , Kurosawa Shunsuke , Yamaji Akihiro , Shoji Yasuhiro , Toyoda Satoshi , Sato Hiroki , Yokota Yuui , Ohashi Yuji , Yoshikawa Akira
Published: July 2020

Ce-doped LaBr3/AEBr2 (AE = Mg, Ca, Sr, Ba) eutectics were grown using the Bridgman–Stockbarger (BS) method in quartz ampoules. The eutectics (AE = Mg and Ca) showed optical transparency like optical fiber bundles. A grown Ce-doped LaBr3/MgBr2 eutectic shows a 355 nm emission ascribed to Ce3+ 4f-5d transition under X-ray excitation. The smaller the ionic size of AE, the higher the light yield of the sample was. The light yield of Ce:LaBr3/MgBr2 was 34,300 photon/MeV, which is higher than Ce:LYSO standard. Scintillation decay time under 662 keV gamma-ray excitation was 18.8 ns.
Molecular Diversity of Nematode Parasites in Afrotropical Reed Frogs (Hyperolius spp.)
Authors: Sinsch Ulrich , Dehling J. Maximilian , Scheid Patrick , Balczun Carsten
Published: July 2020

The diversity of nematodes infecting amphibians is understudied in tropical Africa and unknown in Rwanda. Diversity assessment is hampered by the fact that species descriptions refer mostly to morphological features that are unlinked to DNA sequences of marker genes available in public databases. In this paper, we explore the abundance and diversity of parasitic nematodes in reed frogs Hyperolius kivuensis (n = 115), H. parallelus (n = 45) and H. viridiflavus (n = 100) collected in Rwanda. Five nematode species were identified morphologically as Orneoascaris chrysanthemoides, O. schoutedeni, Gendria leberrei, Aplectana chamaeleonis and Rhabdias collaris. Corresponding DNA sequences of 18S and COI genes were determined and subsequently deposited in GenBank. Aplectana chamaeleonis showed the highest prevalence (8.7%), but O. chrysanthemoides the highest mean intensity of infection (6.0) and largest number (24) of individuals in H. kivuensis. To the best of our knowledge, all amphibian hosts are new records for these nematode species, which are known to infect a wide range of amphibian and reptile species. Our findings suggest that nematode diversity is probably lower than previously assumed due to low host specificity. As morphological species identification is often challenging, our data facilitate molecular identification of adult and specifically larval nematodes found in amphibians of Sub-Saharan Africa.
Spatial Segregation between Red Foxes (Vulpes vulpes), European Wildcats (Felis silvestris) and Domestic Cats (Felis catus) in Pastures in a Livestock Area of Northern Spain
Authors: Rodríguez Alberto , Urra Fermín , Jubete Fernando , Román Jacinto , Revilla Eloy , Palomares Francisco
Published: July 2020

Red foxes, European wildcats and domestic cats share cattle pastures for hunting in La Pernía Valley, northern Spain. To understand the mechanisms that allow the coexistence of these mesopredators in a habitat characterized by its anthropogenic modifications, we recorded sightings of these species in pastures in the summers of 2016, 2017, 2018 and 2019. We tested if the species preferred specific areas of pastures and if they exhibited any spatial segregation in the use of pastures. Red foxes did not show consistent preferences for any area of the pastures. European wildcats preferred pasture areas closer to streams and forest edges, whereas domestic cats preferred areas closer to buildings and paved roads whilst avoiding forest edges. All species pairs showed strong spatial segregation with less than 7% overlap. We hypothesize that spatial segregation is the mechanism used by European wildcats and domestic cats to avoid dangerous interactions with other predators and which characterizes their preference of specific areas on pastures, using areas near places that may protect them from other predators. Ultimately, the influence of fox presence (and probably that of other larger potential predators) on the use of pastures by European wildcats and domestic cats is decreasing the number of interactions between them and may help to prevent hybridization in this area.
Observable and Unobservable Mechanical Motion
Authors: Müller J. Gerhard
Published: July 2020

A thermodynamic approach to mechanical motion is presented, and it is shown that dissipation of energy is the key process through which mechanical motion becomes observable. By studying charged particles moving in conservative central force fields, it is shown that the process of radiation emission can be treated as a frictional process that withdraws mechanical energy from the moving particles and that dissipates the radiation energy in the environment. When the dissipation occurs inside natural (eye) or technical photon detectors, detection events are produced which form observational images of the underlying mechanical motion. As the individual events, in which radiation is emitted and detected, represent pieces of physical action that add onto the physical action associated with the mechanical motion itself, observation appears as a physical overhead that is burdened onto the mechanical motion. We show that such overheads are minimized by particles following Hamilton’s equations of motion. In this way, trajectories with minimum curvature are selected and dissipative processes connected with their observation are minimized. The minimum action principles which lie at the heart of Hamilton’s equations of motion thereby appear as principles of minimum energy dissipation and/or minimum information gain. Whereas these principles dominate the motion of single macroscopic particles, these principles become challenged in microscopic and intensely interacting multi-particle systems such as molecules moving inside macroscopic volumes of gas.
Non-Uniform Embedding Scheme and Low-Dimensional Approximation Methods for Causality Detection
Authors: Papana Angeliki
Published: July 2020

Information causality measures have proven to be very effective in uncovering the connectivity patterns of multivariate systems. The non-uniform embedding (NUE) scheme has been developed to address the “curse of dimensionality”, since the estimation relies on high-dimensional conditional mutual information (CMI) terms. Although the NUE scheme is a dimension reduction technique, the estimation of high-dimensional CMIs is still required. A possible solution is the utilization of low-dimensional approximation (LA) methods for the computation of CMIs. In this study, we aim to provide useful insights regarding the effectiveness of causality measures that rely on NUE and/or on LA methods. In a comparative study, three causality detection methods are evaluated, namely partial transfer entropy (PTE) defined using uniform embedding, PTE using the NUE scheme (PTENUE), and PTE utilizing both NUE and an LA method (LATE). Results from simulations on well known coupled systems suggest the superiority of PTENUE over the other two measures in identifying the true causal effects, having also the least computational cost. The effectiveness of PTENUE is also demonstrated in a real application, where insights are presented regarding the leading forces in financial data.
Traversing the Funambulist’s Fine Line between Nursing and Male Identity: A Systematic Review of the Factors that Influence Men as They Seek to Navigate the Nursing Profession
Authors: Terry Daniel , Peck Blake , Carden Clarissa , Perkins Alicia J. , Smith Andrew
Published: July 2020

Nursing has seen a dominance of women within the profession, and today, the presence of men in the role remains less understood and appreciated. Males considering or entering nursing face challenges concerning role misconception, marginalization, and gender bias. With a looming shortage of nurses on the horizon, it is more important now than ever before to find better ways of engaging males into nursing. The aim of the study was to examine the psychological constructs that influence male perceptions of nursing as they seek to navigate the profession, and what aspects influence men to consider nursing as a career. To achieve this, a systematic review and mixed research synthesis (integrated design) was conducted. English language research published between 1999 and 2019 was eligible. The methodological rigor of qualitative articles followed the Critical Appraisal Skills Program, while the Best Evidence Medical Education guided the quantitative review. Among the 24 publications identified, three sub-themes emerged from the overarching theme of the funambulist or tightrope walker. Sub-themes included societal, inner and collective voices that inform men’s place in nursing or their decision making about entering the profession. There is a need to re-visit what it means to be a nurse in order to address the gendered stereotypes that impact men entering the nursing profession.
Techno-Economic Assessment of Mobilized Thermal Energy Storage System Using Geothermal Source in Polish Conditions
Authors: Matuszewska Dominika , Kuta Marta , Olczak Piotr
Published: July 2020

The paper considers technical and economic possibilities to provide geothermal heat to individual recipients using a mobile thermal storage system (M-TES) in Polish conditions. The heat availability, temperature and heat cost influence the choice of location—Bańska Niżna, near Zakopane in the southern part of the Poland. The indirect contact energy storage container was selected with phase change material characterized by a melting temperature of 70 °C and a heat storage capacity of 250 kJ/kg, in the amount of 800 kg. The economic profitability of the M-TES system (with a price per warehouse of 6000 EUR, i.e., a total of 12,000 EUR—two containers are needed) can be achieved for a heat demand of 5000 kWh/year with the price of a replaced heat source at the level of 0.21 EUR/kWh and a distance between the charging station and building (heat recipient) of 0.5 km. For the heat demand of 15,000 kWh/year, the price for the replaced heat reached EUR 0.11/kWh, and the same distance. In turn, for a demand of 25,000 kWh/year, the price of the replaced heat source reached 0.085 EUR/kWh. The distance significantly affected the economic profitability of the M-TES system—for the analyzed case, a distance around 3–4 km from the heat source should be considered.
Electrical Generation of a Ground-Level Solar Thermoelectric Generator: Experimental Tests and One-Year Cycle Simulation
Authors: Massaguer Eduard , Massaguer Albert , Balló Eudald , Cózar Ivan Ruiz , Pujol Toni , Montoro Lino , Comamala Martí
Published: July 2020

Solar thermoelectric generators (STEGs) are a promising technology to harvest energy for off-grid applications. A wide variety of STEG designs have been proposed with the aim of providing non-intermittent electrical generation. Here, we designed and tested a STEG 0.5 m long formed by nine commercial thermoelectric generator modules and located at ground level. Data were used to validate a numerical model that was employed to simulate a one-year cycle. Results confirmed the very high variability of energy generation during daylight time due to weather conditions. By contrast, energy generation during night was almost independent of atmospheric conditions. Annual variations of nighttime energy generation followed the trend of the daily averaged soil temperature at the bottom of the device. Nighttime electrical energy generation was 5.4 times smaller than the diurnal one in yearly averaged values. Mean energy generation values per day were 587 J d−1 (daylight time) and 110 J d−1 (nighttime). Total annual energy generation was 255 kJ. Mean electrical output power values during daylight and nighttime were 13.4 mW and 2.5 mW, respectively. Annual mean output power was 7.9 mW with a peak value of 79.8 mW.
Modified Impedance-Source Inverter with Continuous Input Currents and Fault-Tolerant Operations
Authors: Yuan Jing , Yang Yongheng , Liu Ping , Shen Yanfeng , Blaabjerg Frede
Published: July 2020

Impedance-source (Z-source) inverters are increasingly adopted in practice, where a high voltage gain is required. However, issues like drawing a non-continuous current from the DC source and ceasing the energy supply under DC source faults are also observed. In this paper, an embedded enhanced-boost Z-source inverter (EEB-ZSI) is thus proposed to tackle the issues. The proposed EEB-ZSI employs two DC sources, which enable the continuous input current and fault-tolerant operations (e.g., open-circuit and short-circuit faults in the DC sources). The operational principles are presented in detail with an in-depth circuit analysis. Moreover, the proposed EEB-ZSI is benchmarked with prior-art Z-source inverters. Experimental tests further demonstrate the effectiveness of EEB-ZSI regarding the continuous input current and flexible fault tolerance.
Improvement of Battery Life and Energy Economy for Electric Vehicles with Two-Speed Transmission
Authors: Lyu Ying , Sun Xuenan , Chu Hong , Gao Bingzhao
Published: July 2020

With the current energy environment background and development of the electrification of the automotive industry, a comprehensive economic indicator, in which the battery aging is further considered on the basis of conventional energy consumption, is proposed to research the energy optimization problem of two-speed electric vehicles. Firstly, a battery life model that adapts to vehicles under high dynamic conditions is introduced. Then, the speed optimal control problem of the two-speed electric vehicles in the acceleration–cruise–deceleration process is established and solved. Finally, the simulation results of two different performance indicators are contrasted and the performance improvement of the two-speed gearbox to the electric vehicles is analyzed. The simulation results under various working scenarios and driving cycles demonstrate that, compared with the conventional economic indicator considering the energy consumption only, the proposed economic indicator can significantly improve the battery life. In addition, it can also be seen that, compared with the one-speed electric vehicles, the application of a two-speed gearbox provides better performance from the aspects of battery aging saving and energy consumption.
Effects of Ammonia Stripping and Other Physico-Chemical Pretreatments on Anaerobic Digestion of Swine Wastewater
Authors: Folino Adele , Calabrò Paolo Salvatore , Zema Demetrio Antonio
Published: July 2020

In order to overcome anaerobic digestion (AD) inhibition due to the large nitrogen content of swine wastewater (SW), air stripping (AS) and other chemical and physical pretreatments were applied on raw SW before AD. The efficiency of these pretreatments on both ammonia removal—recovering ammonia salts to be used as fertilizers in agriculture—and the increase of methane production were assessed in batch tests. Since the pH, temperature, and air flow rate heavily influence AS efficiency and the composition of treated SW, these parameters were set individually or in combination. In more detail, the pH was increased from the natural value of SW to 8 or 10, temperature was increased from the room value to 40 °C, and the air flow rate was increased from zero to 5 Lair LSW−1 min−1. AS was generally more efficient at removing ammonia (up to 97%) from raw (non-treated) SW compared to the other treatments. However, the tested pretreatments were not as efficient as expected in increasing the biogas production, because the methane yields of all pretreated substrates were lower (by about 10–50%) to compared raw SW. The inhibitory effect on AD could have been due to the lack of nutrients and organic matter in the substrate (due to the excessive removal of the pretreatments), the concentration of toxic compounds (such as metal ions or furfural due to water evaporation), and an excess of alkali ions (used to increase the pH in AS). Overall, AS can be considered a sustainable process for the recovery of ammonium sulphate and the removal of other polluting compounds (e.g., organic matter) from SW. Conversely, the use of AS and other chemical and/or thermal processes tested in this study as pretreatments of SW before AD is not advised because these processes appear to reduce methane yields.
Analysis of the Gearbox Oil Maintenance Procedures in Wind Energy
Authors: del Álamo José Ramón , Duran Mario J. , Muñoz Francisco J.
Published: July 2020

This work analyzes the impact of the operation and maintenance procedure on the condition of gearbox oil. The analytical results reveals how different scenarios modify them. The analysis is based on key operational data collected from 30 different multi-megawatt wind turbines at different locations in Spain with a variety of technologies from different top-tier manufacturers. The study includes various situations and decisions, such as leakage and replacement of oil, offline filter installation, oil brand change, substitution of valves, and even the position where the sample is taken and how these situations can provoke false warnings that trigger modifications in the operation and maintenance of wind farms with new unnecessary tasks and costs. The experimental results conclude that complete and reliable information is crucial when warning about risk situations. It is not possible to take appropriate actions without accurate information and consequently the spread of the problem cannot be stopped.
Yokeless Axial Flux Surface-Mounted Permanent Magnets Machine Rotor Parameters Influence on Torque and Back-Emf
Authors: Hajnrych Stanisław J. , Jakubowski Rafał , Szczypior Jan
Published: July 2020

The paper presents the results of a 3D FEA simulations series of a dual air gap Axial Flux (AF) electric machine with Surface-Mounted Permanent magnets (SPM) with parameterized rotor geometry. Pole number and pole span influence on back-emf, as well as cogging and ideal electromagnetic torques angular characteristics were investigated for each model with the common segmented yokeless stator with concentric windings. Synchronous and BLDC drives supply were used to estimate back-emf distortion. Ideal torque ripple and cogging torque spectra were analyzed. It was concluded that the number of poles closer to the number of slots with ~0.8 pole span tends to yield good torque density with the lowest cogging torque, back-emf distortion and ideal torque ripple.
Technology Management Leading to a Smart System Solution Assuring a Decrease of Energy Consumption in Recreational Facilities
Authors: Orynycz Olga , Tucki Karol
Published: July 2020

Improvement of the energy efficiency of public buildings appears to be one of the best ways to simultaneously reduce energy consumption as well as the negative impacts on the environment. The work is dedicated to the analysis of modernization process of the energy system in a sports facility in a way leading to design of smart energy system. The proposed solution, being a specific case study, offers optimal use of energy in the facility, significantly reducing the demand for energy derived from fossil fuels (heat providers and conventional power plants). The project, on its first step, consists of recovering energy from sewage that usually is irretrievably lost. This option allows to achieve the assumed goals simultaneously optimizing the investment costs. The proposed solution mitigates air pollution and harmful gas and dust emissions to the atmosphere, and contributes to an increase of both the attractiveness and competitiveness of the area in which the sports facility is located. The next step will be further automation of the system and intelligent synchronization of time-dependencies of the processes.