bluuebunny/crossref_metadata_2025 huggingface dataset:
Heading Towards a Possible Rebirth of the Induced Renal Cell Carcinoma Models?
Authors: Mazzola Clarisse R. , Ribatti Domenico
Published: March 2020

Introduction: Animal models are interesting tools to improve our knowledge of the pathophysiological processes underlying kidney cancer development. Recent advances have been made in the understanding of the genetic founding events underlying clear cell renal carcinoma. The aim of this paper was to review and discuss the characteristics of all the induced animal models of renal carcinogenesis that have been described in the scientific literature to date and to see if and how they could regain some use in the light of the latest discoveries. Methods: The authors reviewed all the papers available in PubMed regarding induced animal models of renal carcinogenesis. From this perspective, the keywords “induced”, “animal model”, and “renal cancer” were used in PubMed’s search engine. Another search was done using the keywords “induced”, “animal model”, and “kidney cancer”. PRISMA recommendations were used to develop the literature review. Results: Seventy-eight studies were included in this review. Results were presented depending on the mechanisms used to induce carcinogenesis in each model: induction by carcinogens, hormones, viral induction, or induction by other agents. Discussion focused on the possibility to rethink these different induced animal models and use them to answer new research questions. Conclusion: Many induced animal models have been developed in the past to study renal cancer. While these models seemed unable to yield new knowledge, the latest advances in the understanding of the genetics behind renal carcinogenesis could well bring the models back to the forefront.
Comprehensive Immunoprofiles of Renal Cell Carcinoma Subtypes
Authors: Kim Moonsik , Joo Jin Woo , Lee Seok Joo , Cho Yoon Ah , Park Cheol Keun , Cho Nam Hoon
Published: March 2020

In recent years, renal epithelial tumors have been among the fastest reclassifying tumors, requiring updates to the tumor classification system. Nonetheless, immunohistochemistry (IHC) remains the most widely used tool for renal epithelial tumors. In this proposal, we aimed to create the most efficient IHC panel for categorizing the diverse subtypes of renal tumors, and to find out more specific immunohistochemical results in each subtype or each antibody. A total of 214 renal tumors were analyzed using 10 possible IHC markers to differentiate subtypes, including three major renal cell carcinoma (RCC) subtypes, clear-cell type (50 cases), papillary type (50 cases), and chromophobe type (20 cases), and minor subtypes (MiT RCC, 13 cases; collecting duct carcinoma, 5 cases; and oncocytoma, 10 cases). A triple immunomarker (cytokeratin 7 (CK7)-carbonic anhydrase IX (CAIX)- alpha-methylacyl-CoA racemase (AMACR)) panel is useful in particular high-grade clear-cell tumors. If IHC remains ambiguous, the use of an adjunctive panel can be suggested, including CD10, epithelial membrane antigen, cathepsin K, c-kit, hepatocyte nuclear factor 1-β, and E-cadherin. For an efficient immunohistochemical strategy for subtyping of RCC, we conclude that the CK7-CAIX-AMACR panel is the best primary choice for screening subtyping.
Combined wIRA-Hyperthermia and Hypofractionated Re-Irradiation in the Treatment of Locally Recurrent Breast Cancer: Evaluation of Therapeutic Outcome Based on a Novel Size Classification
Authors: Notter Markus , Thomsen Andreas R. , Nitsche Mirko , Hermann Robert M. , Wolff Hendrik A. , Habl Gregor , Münch Karin , Grosu Anca-L. , Vaupel Peter
Published: March 2020

Effective tumor control in patients suffering from unresectable locally recurrent breast cancer (LRBC) in pre-irradiated areas can be achieved by re-irradiation combined with superficial hyperthermia. Using this combined modality, total re-irradiation dose and toxicity can be significantly reduced compared to conventionally fractionated treatment schedules with total doses of 60–66 Gy. Applying contact-free, thermography-controlled water-filtered infrared-A superficial hyperthermia, immediately followed by hypofractionated re-irradiation, consisting of 4 Gy once per week up to a total dose of 20 Gy, resulted in high overall response rates even in large-sized tumors. Comparability of clinical data between different combined Hyperthermia (HT)/Radiotherapy (RT) treatment schedules is impeded by the highly individual characteristics of this disease. Tumor size, ranging from microscopic disease and small lesions to large-sized cancer en cuirasse, is described as one of the most important prognostic factors. However, in clinical studies and analyses of LRBC, tumor size has so far been reported in a very heterogeneous way. Therefore, we suggest a novel, simple and feasible size classification (rClasses 0–IV). Applying this classification for the evaluation of 201 patients with pre-irradiated LRBC allowed for a stratification into distinct prognostic groups.
Human Endogenous Retroviruses (HERVs): Shaping the Innate Immune Response in Cancers
Authors: Alcazer Vincent , Bonaventura Paola , Depil Stephane
Published: March 2020

Human Endogenous Retroviruses (HERVs) are accounting for 8% of the human genome. These sequences are remnants from ancient germline infections by exogenous retroviruses. After million years of evolution and multiple integrations, HERVs have acquired many damages rendering them defective. At steady state, HERVs are mostly localized in the heterochromatin and silenced by methylation. Multiple conditions have been described to induce their reactivation, including auto-immune diseases and cancers. HERVs re-expression leads to RNA (simple and double-stranded) and DNA production (by reverse transcription), modulating the innate immune response. Some studies also argue for a role of HERVs in shaping the evolution of innate immunity, notably in the development of the interferon response. However, their exact role in the innate immune response, particularly in cancer, remains to be defined. In this review, we see how HERVs could be key-players in mounting an antitumor immune response. After a brief introduction on HERVs characteristics and biology, we review the different mechanisms by which HERVs can interact with the immune system, with a focus on the innate response. We then discuss the potential impact of HERVs expression on the innate immune response in cancer.
Selective Oxidation of Methane over Fe-Zeolites by In Situ Generated H2O2
Authors: Kang Jongkyu , Park Eun Duck
Published: March 2020

Liquid-phase selective oxidation of methane into methane oxygenates, including methanol and formic acid, with molecular oxygen was investigated using Fe-zeolites and Pd/activated carbon in the presence of molecular hydrogen as a reducing agent. Various Fe-zeolites such as Fe-ZSM-5, Fe-mordenite, Fe-β, Fe-Y, and Fe-ferrierite were prepared by ion-exchange and compared for this reaction. Among them, Fe-ZSM-5 was selected for further study because this catalyst showed high activity in the selective oxidation of methane with relatively less leaching. Further, the effect of reaction temperature, pH, and the amount of catalyst was examined, and detailed investigations revealed that the leached Fe species, which were facilitated in the presence of acid, were mainly responsible for methane oxidation under the given reaction conditions.
α, β-Alkynone Accelerated PPM Level Pd-Catalyzed Sonogashira Coupling Reaction
Authors: Guo Meng , Wei Zhen , Yang Jianming , Xie Zunyuan , Zhang Weiqiang
Published: March 2020

In the palladium-catalyzed C−C coupling reaction, electron-rich phosphine ligands and a catalytic amount of catalyst loading are required in most cases. Herein, a bench-stable, easily modified and less toxic alkynone was utilized in palladium-catalyzed Sonogashira coupling to replace conventional phosphine ligands. With 1-(4-methoxyphenyl)-3-phenyl-2-yn-1-one (L2) as the ligand, catalyst loading was reduced to 5-10 ppm. In this newly developed catalytic system, a variety of (hetero)arene iodines and alkynes could be tolerated, resulting in good yields of the corresponding cross-coupling products.
Synthesis of Pd-M@HCS(M = Co, Ni, Cu) Bimetallic Catalysts and Their Catalytic Performance for Direct Synthesis of H2O2
Authors: Wang Yaodan , Pan Hongyan , Lin Qian , Shi Yongyong , Zhang Jiesong
Published: March 2020

Hydrogen peroxide (H2O2), as a clean and green oxidant, is widely used in many fields. The direct synthesis of H2O2 (DSHP) from H2 and O2 has attracted most research interest because it relates to a facile, environmentally friendly, and economic process. Yolk–shell Pd-M@HCS (hollow carbon sphere) (M = Co, Ni, Cu) nanocatalysts, in which the bimetal nanoparticle is the core and porous carbon works as the shell layer, are reported in this work. It was found that catalytic activities were enhanced because of the introduced M metals. Additionally, the different mass ratios of Pd to Co (mPd/mCo) were further investigated to improve the catalytic performance for the DSHP. When mPd/mCo was 4.4, the prepared Pd-Co@HCS-(4.4) catalyst, with an average Pd nanoparticle size of 7.30 nm, provided the highest H2O2 selectivity of 87% and H2O2 productivity of 1996 mmolgPd−1·h−1, which were increased by 24% and 253%, respectively, compared to Pd@HCS.
Analysis of Adsorption and Decomposition of Odour and Tar Components in Tobacco Smoke on Non-Woven Fabric-Supported Photocatalysts
Authors: Ochiai Tsuyoshi , Aoki Daisuke , Saito Hidenori , Akutsu Yasuhisa , Nagata Morio
Published: March 2020

The release of substantial amounts of toxicologically significant, irritant, and malodourous compounds during the complete combustion of tobacco can generate an unpleasant environment, especially indoors. Herein, we developed non-woven fabric-supported UV- and visible-light-responsive photocatalysts capable of adsorbing and decomposing the odour and tar components of tobacco smoke under irradiation with UV or visible light. The processes of odour component adsorption and subsequent decomposition under irradiation were evaluated in terms of colour changes in the catalytic system and by gas chromatography–mass spectrometry. By considering three different photocatalysts, namely TiO2, Fe(III)-grafted TiO2, and Cu(II)-grafted WO3, we assessed the magnitude of odour and tar component adsorption on the fabric fibres, as well as the decomposition of these species after specific visible light or UV irradiation periods. Considering the expansion of our technology for practical applications, the best results among the three tested materials were obtained for non-woven fabric-supported Fe/TiO2. We believe that our technology can be implemented in the design of interior decoration materials for creating a comfortable environment.
Cr-Free, Cu Promoted Fe Oxide-Based Catalysts for High-Temperature Water-Gas Shift (HT-WGS) Reaction
Authors: Sourav Sagar , Wachs Israel E.
Published: March 2020

Ca, Ni, Co, and Ge promoters were examined as potential candidates to substitute for the current toxic Cr in Cu-promoted Fe oxide-based catalysts for the HT-WGS reaction. The Ca and Ni promoters were found to improve catalyst performance relative to promotion with Cr. The HS-LEIS surface analysis data demonstrate that Ca and Ge tend to segregate on the surface, while Ni, Co, and Cr form solid solutions in the Fe3O4 bulk lattice. The corresponding number of catalytic active sites, redox, and WGS activity values of the catalysts were determined with CO-TPR, CO+H2O-TPSR, and SS-WGS studies, respectively. The poorer HT-WGS performances of the Ge and Co promoters are related to the presence of surface Ge and Co that inhibits catalyst redox ability, with the Co also not stabilizing the surface area of the Fe3O4 support. The Ni promoter uniformly disperses the Cu nanoparticles on the catalyst surface and increases the number of FeOx-Cu interfacial redox sites. The Ca promoter on the catalyst surface, however, enhances the activity of the FeOx-Cu interfacial redox sites. The CO+H2O TPSR results reveal that the redox ability of the active sites follows the SS-WGS performance of the catalysts and show the following trend: 3Cu8CaFe > 3Cu8NiFe ≥ 3Cu8CrFe > 3Cu8CoFe >> 3Cu8GeFe. Furthermore, all the catalysts followed a redox-type reaction mechanism for the HT-WGS reaction.
DNA Methylation-Based Testing in Liquid Biopsies as Detection and Prognostic Biomarkers for the Four Major Cancer Types
Authors: Constâncio Vera , Nunes Sandra P. , Henrique Rui , Jerónimo Carmen
Published: March 2020

Lung, breast, colorectal, and prostate cancers are the most incident worldwide. Optimal population-based cancer screening methods remain an unmet need, since cancer detection at early stages increases the prospects of successful and curative treatment, leading to a lower incidence of recurrences. Moreover, the current parameters for cancer patients’ stratification have been associated with divergent outcomes. Therefore, new biomarkers that could aid in cancer detection and prognosis, preferably detected by minimally invasive methods are of major importance. Aberrant DNA methylation is an early event in cancer development and may be detected in circulating cell-free DNA (ccfDNA), constituting a valuable cancer biomarker. Furthermore, DNA methylation is a stable alteration that can be easily and rapidly quantified by methylation-specific PCR methods. Thus, the main goal of this review is to provide an overview of the most important studies that report methylation biomarkers for the detection and prognosis of the four major cancers after a critical analysis of the available literature. DNA methylation-based biomarkers show promise for cancer detection and management, with some studies describing a “PanCancer” detection approach for the simultaneous detection of several cancer types. Nonetheless, DNA methylation biomarkers still lack large-scale validation, precluding implementation in clinical practice.
Silencing of Euchromatic Transposable Elements as a Consequence of Nuclear Lamina Dysfunction
Authors: Cavaliere Valeria , Lattanzi Giovanna , Andrenacci Davide
Published: March 2020

Transposable elements (TEs) are mobile genomic sequences that are normally repressed to avoid proliferation and genome instability. Gene silencing mechanisms repress TEs by RNA degradation or heterochromatin formation. Heterochromatin maintenance is therefore important to keep TEs silent. Loss of heterochromatic domains has been linked to lamin mutations, which have also been associated with derepression of TEs. In fact, lamins are structural components of the nuclear lamina (NL), which is considered a pivotal structure in the maintenance of heterochromatin domains at the nuclear periphery in a silent state. Here, we show that a lethal phenotype associated with Lamin loss-of-function mutations is influenced by Drosophila gypsy retrotransposons located in euchromatic regions, suggesting that NL dysfunction has also effects on active TEs located in euchromatic loci. In fact, expression analysis of different long terminal repeat (LTR) retrotransposons and of one non-LTR retrotransposon located near active genes shows that Lamin inactivation determines the silencing of euchromatic TEs. Furthermore, we show that the silencing effect on euchromatic TEs spreads to the neighboring genomic regions, with a repressive effect on nearby genes. We propose that NL dysfunction may have opposed regulatory effects on TEs that depend on their localization in active or repressed regions of the genome.
Opposite Nuclear Dynamics of Two FRH-Dominated Frequency Proteins Orchestrate Non-Rhythmic Conidiation in Beauveria bassiana
Authors: Tong Sen-Miao , Wang Ding-Yi , Cai Qing , Ying Sheng-Hua , Feng Ming-Guang
Published: March 2020

Non-rhythmic conidiation favors large-scale production of conidia serving as active ingredients of fungal insecticides, but its regulatory mechanism is unknown. Here, we report that two FREQUENCY (FRQ) proteins (Frq1/2) governed by a unique FRQ-interacting RNA helicase (FRH) orchestrate this valuable trait in Beauveria bassiana, an asexual insect-pathogenic fungus. Frq1 (964 aa) and Frq2 (583 aa) exhibited opposite expression dynamics (rhythms) in nucleus and steadily high expression levels in cytoplasm under light or in darkness no matter whether one of them was present or absent. Such opposite nuclear dynamics presented a total FRQ (pooled Frq1/2) level sufficient to persistently activate central developmental pathway in daytime and nighttime and supports continuous (non-rhythmic) conidiation for rapid maximization of conidial production in a fashion independent of photoperiod change. Importantly, both nuclear dynamics and cytoplasmic stability of Frq1 and Frq2 were abolished in the absence of the FRH-coding gene nonessential for the fungal viability, highlighting an indispensability of FRH for the behaviors of Frq1 and Frq2 in both nucleus and cytoplasm. These findings uncover a novel circadian system more complicated than the well-known Neurospora model that controls rhythmic conidiation, and provide a novel insight into molecular control of non-rhythmic conidiation in B. bassiana.
Regulation of Necroptosis by Phospholipids and Sphingolipids
Authors: Zhang Xuewei , Matsuda Masaya , Yaegashi Nobuo , Nabe Takeshi , Kitatani Kazuyuki
Published: March 2020

Several non-apoptotic regulated cell death pathways have been recently reported. Necroptosis, a form of necrotic-regulated cell death, is characterized by the involvement of receptor-interacting protein kinases and/or the pore-forming mixed lineage kinase domain-like protein. Recent evidence suggests a key role for lipidic molecules in the regulation of necroptosis. The purpose of this mini-review is to outline the regulation of necroptosis by sphingolipids and phospholipids.
Stress Erythropoiesis is a Key Inflammatory Response
Authors: Paulson Robert F. , Ruan Baiye , Hao Siyang , Chen Yuanting
Published: March 2020

Bone marrow medullary erythropoiesis is primarily homeostatic. It produces new erythrocytes at a constant rate, which is balanced by the turnover of senescent erythrocytes by macrophages in the spleen. Despite the enormous capacity of the bone marrow to produce erythrocytes, there are times when it is unable to keep pace with erythroid demand. At these times stress erythropoiesis predominates. Stress erythropoiesis generates a large bolus of new erythrocytes to maintain homeostasis until steady state erythropoiesis can resume. In this review, we outline the mechanistic differences between stress erythropoiesis and steady state erythropoiesis and show that their responses to inflammation are complementary. We propose a new hypothesis that stress erythropoiesis is induced by inflammation and plays a key role in maintaining erythroid homeostasis during inflammatory responses.
Molecular Rewiring of the Jasmonate Signaling Pathway to Control Auxin-Responsive Gene Expression
Authors: Li Ning , Cao Linggai , Miu Wenzhuo , Cao Ruibin , Peng Mingbo , Wan Wenkai , Huang Li-Jun
Published: March 2020

The plant hormone jasmonic acid (JA) has an important role in many aspects of plant defense response and developmental process. JA triggers interaction between the F-box protein COI1 and the transcriptional repressors of the JAZ family that leads the later to proteasomal degradation. The Jas-motif of JAZs is critical for mediating the COI1 and JAZs interaction in the presence of JA. Here, by using the protoplast transient gene expression system we reported that the Jas-motif of JAZ1 was necessary and sufficient to target a foreign reporter protein for COI1-facilitated degradation. We fused the Jas-motif to the SHY2 transcriptional repressor of auxin signaling pathway to create a chimeric protein JaSHY. Interestingly, JaSHY retained the transcriptional repressor function while become degradable by the JA coreceptor COI1 in a JA-dependent fashion. Moreover, the JA-induced and COI1-facilitated degradation of JaSHY led to activation of a synthetic auxin-responsive promoter activity. These results showed that the modular components of JA signal transduction pathway can be artificially redirected to regulate auxin signaling pathway and control auxin-responsive gene expression. Our work provides a general strategy for using synthetic biology approaches to explore and design cell signaling networks to generate new cellular functions in plant systems.
Second Law Analysis of Ciliary Pumping Transport in an Inclined Channel Coated with Carreau Fluid under a Magnetic Field
Authors: Munawar Sufian , Saleem Najma
Published: March 2020

A complete thermal analysis is performed for the propulsion of cilia in an inclined channel. Coating around the channel walls is provided by a Carreau fluid under a uniform magnetic field. Uniformly grown cilia produce propulsive metachronal waves by moving in a coordinated rhythm along the channel surface and adapt an elliptic path along the direction of flow. Using lubrication approximations, the governing equations, formulated in the wave frame of reference, are solved by the perturbation method. Validation of the analytic solution is provided by computing the solution numerically with the shooting method. This study is concerned with the parametric consequences on pertinent flow and heat transfer quantities, such as streamlines, velocity profile, temperature profile, entropy lines and the Bejan number. The results reveal that large cilia propel the axial velocity near the channel wall but put hindrance to the axial velocity and the temperature profile in the central part of the channel. The entropy production in the channel reduces for large cilia and a high Hartmann number.
Anti-Corrosive Properties of an Effective Guar Gum Grafted 2-Acrylamido-2-Methylpropanesulfonic Acid (GG-AMPS) Coating on Copper in a 3.5% NaCl Solution
Authors: Singh Ambrish , Liu Mingxing , Ituen Ekemini , Lin Yuanhua
Published: March 2020

Guar gum grafted 2-acrylamido-2-methylpropanesulfonic acid (GG-AMPS) was synthesized using guar gum and AMPS as the base ingredients. The corrosion inhibition of copper was studied using weight loss, electrochemical, and surface characterization methods in a 3.5% sodium chloride (NaCl) solution. Studies including weight loss were done at different acid concentrations, different inhibitor concentrations, different temperatures, and different immersion times. The weight loss studies showed the good performance of GG-AMPS at a 600 mg/L concentration. This concentration was further used as the optimum concentration for all of the studies. The efficiency decreased with the rise in temperature and at higher concentrations of acidic media. However, the efficiency of the inhibition increased with the additional immersion time. Electrochemical methods including impedance and polarization were employed to calculate the inhibition efficiency. Both of the techniques exhibited a good inhibition by GG-APMS at a 600 mg/L concentration. Surface studies were conducted using scanning electrochemical microscopy (SECM), scanning electron microscopy (SEM), and atomic force microscopy (AFM) methods. The surface studies showed smooth surfaces in the presence of GG-AMPS and rough surfaces in its absence. The adsorption type of GG-AMPS on the surface of the copper followed the Langmuir adsorption model.
Facilitating TiB2 for Filtered Vacuum Cathodic Arc Evaporation
Authors: Brzezinka Tomasz L. , Rao Jeff , Paiva Jose M. , Azkona Ibon , Kohlscheen Joern , Fox Rabinovich German S. , Veldhuis Stephen C. , Endrino Jose L.
Published: March 2020

TiB2 is well established as a superhard coating with a high melting point and a low coefficient of friction. The brittle nature of borides means they cannot be utilised with arc evaporation, which is commonly used for the synthesis of hard coatings as it provides a high deposition rate, fully ionised plasma and good adhesion. In this work, TiB2 conical cathodes with non-standard sintering additives (carbon and TiSi2) were produced, and the properties of the base material, such as grain structure, hardness, electrical resistivity and composition, were compared to those of monolithic TiB2. The dependence of the produced cathodes’ electrical resistivity on temperature was evaluated in a furnace with an argon atmosphere. Their arc–evaporation suitability was assessed in terms of arc mobility and stability by visual inspection and by measurements of plasma electrical potential. In addition, shaping the cathode into a cone allowed investigation of the influence of an axial magnetic field on the arc spot. The produced cathodes have a bulk hardness of 23–24 GPa. It has been found that adding 1 wt% of C ensured exceptional arc-spot stability and mobility, and requires lower arc current compared to monolithic TiB2. However, poor cathode utilization has been achieved due to the steady generation of cathode flakes. The TiB2 cathode containing 5 wt% of TiSi2 provided the best balance between arc-spot behaviour and cathode utilisation. Preventing cathode overheating has been identified as a main factor to allow high deposition rate (±1.2 µm/h) from TiB2-C and TiB2-TiSi2 cathodes.
Dielectric Response of ZnTe–Ti/Al Schottky Junctions with CdTe Quantum Dots Studied by Impedance Spectroscopy
Authors: Zielony Eunika , Płaczek-Popko Ewa , Karczewski Grzegorz
Published: March 2020

The electrical properties of ZnTe–Ti/Al Schottky junctions were investigated by the impedance spectroscopy (IS) method. Current-voltage (I-V) and capacitance-voltage (C-V) measurements were also performed. The studied samples were the CdTe quantum dot structures embedded in ZnTe matrix and a reference ZnTe sample without quantum dots. C-V characteristics confirmed the presence of quantum dots (QDs) in the structures. Electric modulus and impedance data were analyzed. IS studies proved that long-range conductivity governs the relaxation processes in the junctions. For both samples, the data were fitted with a simple RC circuit composed of a depletion layer capacitance in parallel with bulk resistance and a series resistance of contacts. The activation energy of the relaxation process observed for the reference sample obtained from the Arrhenius plot of the resistance, imaginary impedance, and electric modulus equals 0.4 eV at zero bias. For the quantum dot sample, the value of activation energy determined with the help of the same methods equals 0.2 eV. In conclusion, it was assumed that the relaxation processes for the reference sample are attributed to the trap present in ZnTe host material, whereas those observed for the QD structure are assigned to the deep level associated with defects located close to the QDs created during their growth.
A Novel Ag-N-Heterocyclic Carbene Complex Bearing the Hydroxyethyl Ligand: Synthesis, Characterization, Crystal and Spectral Structures and Bioactivity Properties
Authors: Aktas Aydin , Barut Celepci Duygu , Gok Yetkin , Taslimi Parham , Akincioglu Hulya , Gulcin İlhami
Published: March 2020

In this study, a novel silver N-heterocyclic carbene (Ag-NHC) complex bearing hydroxyethyl substituent has been synthesized from the hydroxyethyl-substituted benzimidazolium salt and silver oxide by using in-situ deprotonation method. A structure of the Ag-NHC complex was characterized by using UV-Vis, FTIR, 1H-NMR and 13C-NMR spectroscopies and elemental analysis techniques. Also, the crystal structure of the novel complex was determined by single-crystal X-ray diffraction method. In this paper, compound 1 showed excellent inhibitory effects against some metabolic enzymes. This complex had Ki of 1.14 0.26 µM against human carbonic anhydrase I (hCA I), 1.88±0.20 µM against human carbonic anhydrase II (hCA I), and 10.75±2.47 µM against α-glycosidase, respectively. On the other hand, the Ki value was found as 25.32±3.76 µM against acetylcholinesterase (AChE) and 41.31±7.42 µM against butyrylcholinesterase (BChE), respectively. These results showed that the complex had drug potency against some diseases related to using metabolic enzymes.
Experimental and Theoretical Investigation of the Elastic Properties of HfV2O7
Authors: Ravensburg Anna L. , Keuter Philipp , Music Denis , Miljanovic Danilo J. , Schneider Jochen M.
Published: March 2020

We investigated the elastic properties of the HfV2O7 high-temperature phase, exhibiting negative thermal expansion, in a synergetic strategy of first-principle calculations and nanoindentation experiments performed on sputtered films. Self-consistent results were obtained for the measured elastic modulus (73 ± 14 GPa) and dispersion-corrected density functional theory calculations. The elastic properties of HfV2O7 are affected by long-range dispersion interaction, which may be induced by severe modification in the second-nearest neighbor O-O bond distance as obtained upon compression. HfV2O7 is composed of HfO6, VO4, and V2O7 building blocks, whereby the latter is characterized by an increasing V-O(-V) bond length upon compression.
Mechanical, Dielectric, and Thermal Attributes of Polyimides Stemmed Out of 4, 4’–Diaminodiphenyl Ether
Authors: Zhang Panpan , Zhang Ke , Dou Shuliang , Zhao Jiupeng , Yan Xiangqiao , Li Yao
Published: March 2020

Several kinds of polyimide (PI) films stemmed out of 4, 4’–diaminodiphenyl ether, as well as various structurally various aromatic dianhydride, were prepared. The films’ mechanical, dielectric, and dynamic mechanical attributes were put under investigation. According the findings, the PI films’ performance is significantly different as a result of their diverse structure. PI’s dielectric constant and dielectric loss tangent of abides by the increasing order below: PMDA-PI>BTDA-PI>BPDA-PI. Moreover, the electric breakdown strength of BTDA-PI (478.90 kV/mm) presents a lot higher value compared to the one PMDA-PI (326.80 kV/mm) and BPDA-PI (357.07 kV/mm). In particular, BTDA-PI film possesses high electric breakdown strength about 478.90 kV/mm. In addition, PI’s glass transition temperature (Tg) are, respectively, 276 °C (BTDA-PI), and 290 °C (BPDA-PI), as well as 302 °C (PMDA-PI). Therefore, in virtue of their various structures and performances, practical applications of PI films can exert significant role in the electronics and microelectronics industries.
Dataset of Targeted Metabolite Analysis for Five Taxanes of Hellenic Taxus baccata L. Populations
Authors: Dalmaris Eleftheria , Avramidou Evangelia V. , Xanthopoulou Aliki , Aravanopoulos Filippos A.
Published: March 2020

Novel primary sources of one of the world’s leading anticancer agent, paclitaxel, as well as of other antineoplastic taxanes such as 10-deacetylbaccatin-III, are needed to meet an increasing demand. Among the Taxus species the promise of Taxus baccata L. (European or English yew) has been documented. In this study, the metabolite analysis of two marginal T. baccata populations in Greece (Mt. Cholomon and Mt. Olympus), located at the southeastern edge of the species natural distribution, are being explored. A targeted liquid chromatography – mass spectrometry (LC-MS/MS) analysis was used to determine the content of 10-deacetylbaccatin III, baccatin III, 10-deacetyltaxol, paclitaxel and cephalomannine in the needles of each of the populations from three sampling periods (spring, summer and winter). This is the first survey to generate a taxane targeted metabolite data set, since it derives from Hellenic natural populations that have not been explored before. Furthermore, it has used an extensive sample design in order to evaluate chemodiversity at the population level. The analysis revealed significant levels of chemodiversity within and among the investigated populations and significant seasonal variation that could be exploited for the selection of superior germplasm native to Greece, for yew plantations and further exploitation which is necessary for the production of important taxanes.
Symmetry-Like Relation of Relative Entropy Measure of Quantum Coherence
Authors: Zhang Chengyang , Guo Zhihua , Cao Huaixin
Published: March 2020

Quantum coherence is an important physical resource in quantum information science, and also as one of the most fundamental and striking features in quantum physics. To quantify coherence, two proper measures were introduced in the literature, the one is the relative entropy of coherence C r ( ρ ) = S ( ρ diag ) − S ( ρ ) and the other is the ℓ 1 -norm of coherence C ℓ 1 ( ρ ) = ∑ i ≠ j | ρ i j | . In this paper, we obtain a symmetry-like relation of relative entropy measure C r ( ρ A 1 A 2 ⋯ A n ) of coherence for an n-partite quantum states ρ A 1 A 2 ⋯ A n , which gives lower and upper bounds for C r ( ρ ) . As application of our inequalities, we conclude that when each reduced states ρ A i is pure, ρ A 1 ⋯ A n is incoherent if and only if the reduced states ρ A i and tr A i ρ A 1 ⋯ A n ( i = 1 , 2 , … , n ) are all incoherent. Meanwhile, we discuss the conjecture that C r ( ρ ) ≤ C ℓ 1 ( ρ ) for any state ρ , which was proved to be valid for any mixed qubit state and any pure state, and open for a general state. We observe that every mixture η of a state ρ satisfying the conjecture with any incoherent state σ also satisfies the conjecture. We also observe that when the von Neumann entropy is defined by the natural logarithm ln instead of log 2 , the reduced relative entropy measure of coherence C ¯ r ( ρ ) = − ρ diag ln ρ diag + ρ ln ρ satisfies the inequality C ¯ r ( ρ ) ≤ C ℓ 1 ( ρ ) for any state ρ .
Commensurate and Non-Commensurate Fractional-Order Discrete Models of an Electric Individual-Wheel Drive on an Autonomous Platform
Authors: Bąkała Marcin , Duch Piotr , Tenreiro Machado J. A. , Ostalczyk Piotr , Sankowski Dominik
Published: March 2020

This paper presents integer and linear time-invariant fractional order (FO) models of a closed-loop electric individual-wheel drive implemented on an autonomous platform. Two discrete-time FO models are tested: non-commensurate and commensurate. A classical model described by the second-order linear difference equation is used as the reference. According to the sum of the squared error criterion (SSE), we compare a two-parameter integer order model with four-parameter non-commensurate and three-parameter commensurate FO descriptions. The computer simulation results are compared with the measured velocity of a real autonomous platform powered by a closed-loop electric individual-wheel drive.
A New Concept and a Test of a Bubble Pump System for Passive Heat Transport from Solar Collectors
Authors: Chludziński Daniel , Duda Michał
Published: March 2020

Heat is usually transported by hydraulic circuits where the working medium is circulated by an electric pump. Heat can also be transferred by natural convection in passive systems. Passive systems where heat is transported downward have also been described and studied in the literature. These types of devices are referred to as reverse thermosiphons. However, systems of the type are not widely applied in practice due to the problems associated with the selection of the optimal working medium. In water-based thermosiphons, negative pressure is produced when water temperature falls below 100 °C, and non-condensable gas can enter the system. These problems are not encountered in systems where the working medium has a low boiling point. However, liquids with a low boiling point can be explosive, expensive, and harmful to the environment. The solution proposed in this paper combines the advantages of water and a liquid with a low boiling point. The described system relies on water as the heat transfer medium and small amounts of a substance with a low boiling point. The developed model was tested under laboratory conditions to validate the effectiveness of a passive system where heat is transported downward with the involvement of two working media. The system’s operating parameters are also described.
Optimization of Low-Power Line-Start PM Motor Using Gray Wolf Metaheuristic Algorithm
Authors: Knypiński Łukasz , Pawełoszek Karol , Le Menach Yvonnick
Published: March 2020

The paper presents the optimization method and computer software for the design of a low-power line-start permanent magnet synchronous motor (LSPMSM). The in-house-developed computer software was created with two independent modules: (a) the optimization procedure and (b) the numerical model of the motor. The optimization procedure used was a metaheuristic optimization method based on the gray wolf algorithm. Four design variables linked to the rotor structure were selected. The optimization process was performed from the rotor of a low-power induction motor (IM). The prototype of the motor (LSPMSM) was then built. The experimental measurements were performed for base the IM and optimized LSPMSM. The results of the measurements were compared for both motors. The experimental results confirmed the better performance of the designed motor in comparison to the induction motor.
Grid-Tied Distributed Generation Systems to Sustain the Smart Grid Transformation: Tariff Analysis and Generation Sharing
Authors: Yanine Fernando , Sánchez-Squella Antonio , Barrueto Aldo , Parejo Antonio , Cordova Felisa , Rother Hans
Published: March 2020

In this paper a novel model is being proposed and considered by ENEL—the largest electric utility in Chile—and analyzed thoroughly, whereby electric power control and energy management for a 60-apartments’ residential building is presented as an example of the utility’s green energy program, part of its Smart Grid Transformation plan to install grid-tied distributed generation (DG) systems, namely microgrids, with solar generation and energy storage in Santiago, Chile. The particular tariffs scheme analysis shown is part of the overall projected tentative benefits of adopting the new scheme, which will require the utility’s customers to adapt their consumption behavior to the limited supply of renewable energy by changing energy consumption habits and schedules in a way that maximizes the capacity and efficiency of the grid-tied microgrid with energy storage. The change in behavior entails rescheduling power consumption to hours where the energy supply capacity in the DG system is higher and price is lower as well as curtailing their power needs in certain hourly blocks so as to maximize DG system’s efficiency and supply capacity. Nevertheless, the latter presents a problem under the perspective of ENEL’s renewable energy sources (RES) integration plan with the electric utility’s grid supply, which, up until now and due to current electric tariffs law, has not had a clear solution. Under said scenario, a set of strategies based on energy homeostasis principles for the coordination and control of the electricity supply versus customers’ demand has been devised and tested. These strategies which consider various scenarios to conform to grid flexibility requirements by ENEL, have been adapted for the specific needs of these types of customers while considering the particular infrastructure of the network. Thus, the microgrid adjusts itself to the grid in order to complement the grid supply while seeking to maximize green supply capacity and operational efficiency, wherein the different energy users and their energy consumption profiles play a crucial role as “active loads”, being able to respond and adapt to the needs of the grid-connected microgrid while enjoying economic benefits. Simulation results are presented under different tariff options, system’s capacity and energy storage alternatives, in order to compare the proposed strategies with the actual case of traditional grid’s electricity distribution service, where no green energy is present. The results show the advantage of the proposed tariffs scheme, along with power control and energy management strategies for the integration of distributed power generation within ENEL’s Smart Grid Transformation in Chile.
Management and Activation of Energy Flexibility at Building and Market Level: A Residential Case Study
Authors: Taddeo Paolo , Colet Alba , Carrillo Rafael E. , Casals Canals Lluc , Schubnel Baptiste , Stauffer Yves , Bellanco Ivan , Corchero Garcia Cristina , Salom Jaume
Published: March 2020

The electricity sector foresees a significant change in the way energy is generated and distributed in the coming years. With the increasing penetration of renewable energy sources, smart algorithms can determine the difference about how and when energy is produced or consumed by residential districts. However, managing and implementing energy demand response, in particular energy flexibility activations, in real case studies still presents issues to be solved. This study, within the framework of the European project “SABINA H2020”, addresses the development of a multi-level optimization algorithm that has been tested in a semi-virtual real-time configuration. Results from a two-day test show the potential of building’s flexibility and highlight its complexity. Results show how the first level algorithm goal to reduce the energy injected to the grid is accomplished as well as the energy consumption shift from nighttime to daytime hours. As conclusion, the study demonstrates the feasibility of such kind of configurations and puts the basis for real test site implementation.
Model Predictive Base Direct Speed Control of Induction Motor Drive—Continuous and Finite Set Approaches
Authors: Wróbel Karol , Serkies Piotr , Szabat Krzysztof
Published: March 2020

In the paper a comparative study of the two control structures based on MPC (Model Predictive Control) for an electrical drive system with an induction motor are presented. As opposed to the classical approach, in which DFOC (Direct Field Oriented Control) with four controllers is considered, in the current study only one MPC controller is utilized. The proposed control structures have a cascade free structure that consists of a vector of electromagnetic (torque, flux) and mechanical (speed) states of the system. The first investigated framework is based on the finite-set MPC. A short horizon predictive window is selected. The continuous set MPC is used in the second framework. In this case the predictive horizon contains several samples. The computational complexity of the algorithm is reduced by applying its explicit version. Different implementation aspects of both MPC structures, for instance the model used in prediction, complexity of the control algorithms, and their properties together with the noise level are analyzed. The effectiveness of the proposed approach is validated by some experimental tests.
Impacts of a LVRT Control Strategy of Offshore Wind Farms on the HTS Power Cable
Authors: Nguyen Thai-Thanh , Kim Hak-Man , Yang Hyung Suk
Published: March 2020

High temperature superconducting (HTS) power cables are a potential solution for the grid integration of offshore wind farms since the HTS cable can conduct bulk wind power at low voltage levels. However, the transient current through the HTS cable in cases of low voltage ride through (LVRT) operation has a negative impact on the HTS cable operation due to the quenching phenomenon. This paper analyzes the impact of LVRT control strategies on the HTS cable operation. In addition, a coordinated control of wind turbines for LVRT improvement of an offshore wind farm is proposed. The feasibility of the HTS cable application for the grid connection of offshore wind farms is also discussed in this study. The proposed controller is designed for the wind turbine generator based on a type-4 permanent magnet synchronous generator. In the proposed controller, the transient current through the HTS cable is reduced by regulating the machine side power during fault conditions. The feasibility of the proposed controller is validated in the PSCAD/EMTDC program (Manitoba Hydro International Ltd., Winnipeg, Manitoba, Canada, version 4.2.1). The effects of transient current on the cable temperatures and resistances are analyzed in this study. Simulation results show that the proposed control strategy could reduce the transient current and temperature rise of the HTS cable.
SiC-Based High Efficiency High Isolation Dual Active Bridge Converter for a Power Electronic Transformer
Authors: Saeed Mariam , Rogina María R. , Rodríguez Alberto , Arias Manuel , Briz Fernando
Published: March 2020

This paper discusses the benefits of using silicon carbide (SiC) devices in a three-stage modular power electronic transformer. According to the requirements to be fulfilled by each stage, the second one (the DC/DC isolation converter) presents the most estimable improvements to be gained from the use of SiC devices. Therefore, this paper is focused on this second stage, implemented with a SiC-based dual active bridge. Selection of the SiC devices is detailed tackling the efficiency improvement which can be obtained when they are co-packed with SiC antiparallel Schottky diodes in addition to their intrinsic body diode. This efficiency improvement is dependent on the dual active bridge operation point. Hence, a simple device loss model is presented to assess the efficiency improvement and understand the reasons for this dependence. Experimental results from a 5-kW Dual Active Bridge prototype have been obtained to validate the model. The dual active bridge converter is also tested as part of the full PET module operating at rated power.
Evaluation of Ozone Generation in Volume Spiral-Tubular Dielectric Barrier Discharge Source
Authors: Zylka Pawel
Published: March 2020

Ozone, due to its high reactivity cannot be stockpiled, and thus requires to be generated on-demand. The paper reports on laboratory studies of O3 generation in a volume dielectric barrier discharge (DBD) tubular flow-through system with a coaxial-spiral electrode arrangement. Its performance is experimentally verified and compared to a commercial surface DBD O3 source fitted with a three-electrode floating supply arrangement. The presented volume DBD design is capable of steadily producing up to 4180 ppmv O3 at 1 Nl/min unprocessed atmospheric air intake and 10 kV 1.6 kHz sinusoidal high voltage supply corresponding to 67 g/kWh O3 production yield increasing to 93 g/kWh at 100 Nl/min air intake. The effects of high voltage supply tuning are also investigated and discussed together with finite element method simulation results.
Linear Active Disturbance Rejection Control for DC Bus Voltage Under Low-Voltage Ride-Through at the Grid-Side of Energy Storage System
Authors: Ma Youjie , Yang Luyong , Zhou Xuesong , Yang Xia , Zhou Yongliang , Zhang Bo
Published: March 2020

The energy storage inverter system has the characteristics of nonlinearity, strong coupling, variable parameters, and flexible mode switching between parallel and off grid. In order to improve the control performance of the grid-side inverter of the energy storage system, an improved Linear Active Disturbance Rejection Control (LADRC) based on proportional differentiation is proposed to replace the traditional LADRC in the voltage outer loop control. In this paper, the observation gain coefficient of the sum of the disturbances of the traditional Linear Extended State Observer (LESO) is improved to a proportional differentiation link, which effectively reduces the degree of the disturbance observation amplitude drop and the phase lag, and increases the observation bandwidth of LESO. Compared with traditional LADRC, it not only improves the observation accuracy of LESO for disturbance, but also improves the anti-interference performance of LADRC. Finally, the control effects of improved LADRC and traditional LADRC on low-voltage ride-through at different degrees are analyzed and compared through simulation, which proves the rationality of the controller designed in this paper.