bluuebunny/crossref_metadata_2025_split huggingface dataset:
Surge arrester operation investigation in low‐ and high‐current regions using MATLAB GUI: Implementing an educational goal for undergraduate students
Authors: Seyyedbarzegar Seyyedmeysam , Khodsuz Masume 
Published: January 2021

AbstractMetal oxide surge arresters (MOSAs) have been widely used as protective devices against switching and lightning overvoltages in power electrical systems. MOSAs have dynamic characteristics in low‐ and high‐current regions. The unique model of MOSA, which is able to evaluate all the possible operating conditions of power systems, would surely be so complicated. Therefore, by the selection of an operating condition, the appropriate model of MOSA has been created. Many parameters affect MOSA performance in low‐ and high‐current regions. As a result, MOSA's performance under different operating conditions has been investigated by using a MATLAB GUI environment. To make a software environment to simulate MOSA performance in a high voltage laboratory, temperature variations influence on leakage current and its harmonic components under power frequency applied voltages and also the efficacy of impulse parameters variations on MOSA's residual voltage have been investigated. The designed graphical environment has been used by 40 electrical engineering students. The results showed that the use of the graphical environment had a great impact on the concepts' understanding of MOSA's performance.
Inducible CRISPR‐dCas9 Transcriptional Systems for Sensing and Genome Regulation
Authors: Wu Han , Wang Fenglin , Jiang Jian‐Hui 
Published: January 2021

AbstractThe clustered, regularly interspaced short palindromic repeats‐associated protein 9 endonuclease (CRISPR‐Cas9) and the nuclease‐deactivated Cas9 (dCas9) systems have revolutionized our ability to precisely engineer and regulate genomes. Inducible CRISPR‐dCas9‐based transcriptional systems have been rapidly developed to conditionally control genetic manipulation. Current strategies mainly focus on conditional control of gRNA function and dCas9 protein using exogenous and endogenous triggers, including external light, small molecules, synthetic and intracellular oligonucleotides. These strategies have established novel platforms for the spatiotemporal regulation of genome activation and repression, epigenome editing, and so on. Herein, we summarize the recent progress in conditionally controlling CRISPR‐dCas9 transcriptional systems through gRNA modulation and dCas9 protein engineering.
Stable Hairpin Structures Formed by Xylose‐Based Nucleic Acids
Authors: Mattelaer Charles‐Alexandre , Maiti Mohitosh , Smets Laurent , Maiti Munmun , Schepers Guy , Mattelaer Henri‐Philippe , Rosemeyer Helmut , Herdewijn Piet , Lescrinier Eveline 
Published: January 2021

AbstractXenobiology explores synthetic nucleic acid polymers as alternative carriers of genetic information to expand the central dogma. The xylo‐ and deoxyxylo‐nucleic acids (XyNA and dXyNA), containing 3’ epimers of riboses and deoxyriboses, are considered to be potential candidates for an orthogonal system. In this study, thermal and spectroscopic analyses show that XyNA and dXyNA form stable hairpins. The dXyNA hairpin structure determined by NMR spectroscopy contains a flexible loop that locks the stem into a stable ladder‐like duplex with marginal right‐handed helicity. The reduced flexibility of the dXyNA duplex observed in the stem of the hairpin demonstrates that folding of dXyNA yields more stable structures described so far.
Tagged Benzoxazin‐4‐Ones as Novel Activity‐Based Probes for Serine Proteases
Authors: Yang Jian , Mendowicz Rafal J. , Verhelst Steven H. L. 
Published: January 2021

AbstractActivity‐based probes (ABPs) are valuable chemical tools for profiling enzymes. They have been particularly useful in the study of proteases. ABPs rely on electrophilic scaffolds that covalently modify the target enzymes. Ideally, they can be made in a fast and uncomplicated manner. Here, we explore alkyne‐substituted benzoxazin‐4‐ones as ABPs for serine proteases, because they inhibitserine proteases covalently and their synthesis is very straightforward. We show that alkyne‐tagged benzoxazin‐4‐ones can be used in two‐step bioorthogonal tandem labeling procedures or pre‐functionalized with a biotin or fluorophore. We demonstrate that these reagents can be used to label and identify various serine proteases. Therefore, we expect that tagged benzoxazin‐4‐ones will offer easily synthesizable tools for profiling of serine proteases.
Distinct immunomodulatory properties of extracellular vesicles released by different strains of Acanthamoeba
Authors: Costa Adriana Oliveira , Chagas Isabela Aurora Rodrigues , de Menezes‐Neto Armando , Rêgo Felipe Dutra , Nogueira Paula Monalisa , Torrecilhas Ana Claudia , Furst Cinthia , Fux Blima , Soares Rodrigo Pedro 
Published: January 2021

AbstractFree living amoeba of the genus Acanthamoeba are opportunist protozoan involved in corneal, systemic, and encephalic infections in humans. Most of the mechanisms underlying intraspecies variations and pathogenicity are still unknown. Recently, the release of extracellular vesicles (EVs) by Acanthamoeba was reported. However, comparative characterization of EVs from distinct strains is not available. The aim of this study was to evaluate EVs produced by Acanthamoeba from different genotypes, comparing their proteases profile and immunomodulatory properties. EVs from four environmental or clinical strains (genotypes T1, T2, T4, and T11) were obtained by ultracentrifugation, quantitated by nanoparticle tracking analysis and analyzed by scanning and transmission electron microscopy. Proteases profile was determined by zymography and functional properties of EVs (measure of nitrite and cytokine production) were determined after peritoneal macrophage stimulation. Despite their genotype, all strains released EVs and no differences in size and/or concentration were detected. EVs exhibited a predominant activity of serine proteases (pH 7.4 and 3.5), with higher intensity in T4 and T1 strains. EVs from the environmental, nonpathogenic T11 strain exhibited a more proinflammatory profile, inducing higher levels of Nitrite, tumor necrosis factor alpha and interleukin‐6 via TLR4/TLR2 than those strains with pathogenic traits (T4, T1, and T2). Preincubation with EVs treated with protease inhibitors or heating drastically decreased nitrite concentration production in macrophages. Those data suggest that immunomodulatory effects of EVs may reflect their pathogenic potential depending on the Acanthamoeba strains and are dependent on protease integrity.
Complete response of cutaneous SCC to topical treatment with ascorbic acid solution: A case report
Authors: Pernice Carmine , Murri Domenico , Valli Riccardo , Crocetta Francesco M. , Iori Michele , Asti Mattia , Ghidini Angelo , Capponi Pier C. 
Published: January 2021

AbstractClinical use of topical ascorbic acid solution could have both the role as an adjunct to consolidated therapies and as an alternative to them, for the treatment of BCC and SCC of the skin.
Utility of objective gait measures in levodopa‐unresponsive freezing in Parkinson's
Authors: Virmani Tuhin , Glover Aliyah , Pillai Lakshmi , Lotia Mitesh , Dhall Rohit 
Published: January 2021

AbstractLevodopa‐unresponsive gait freezing in Parkinson disease is debilitating. Gait kinematics, while time‐consuming, can help optimize levodopa's benefit on gait stride length and stride velocity, and thereby improve freezing and falls in these patients.
High‐grade B‐cell lymphoma developed during the treatment of chronic myeloid leukemia with bosutinib
Authors: Takakuwa Teruhito , Sakai Ryota , Koh Shiro , Okamura Hiroshi , Nanno Satoru , Nakashima Yasuhiro , Nakane Takahiko , Koh Hideo , Hino Masayuki , Nakamae Hirohisa 
Published: January 2021

AbstractTyrosine kinase inhibitor (TKI) can help to increase the survival time in chronic myeloid leukemia (CML) patients; however, the risk of secondary malignancies due to TKIs is a growing concern. Only few reports showed clinical course of patients who developed lymphoma during TKI therapies. Herein, we report a case of high‐grade B‐cell lymphoma diagnosed in the course of CML treatment with bosutinib. The 75‐year‐old male patient had been diagnosed with CML 25 years ago. After receiving TKIs (imatinib, nilotinib, and bosutinib), he achieved a major molecular response. Over 3 years after starting bosutinib, he was diagnosed with a high‐grade B‐cell lymphoma. A total of six courses of DA‐EPOCH‐R therapy brought complete remission of the lymphoma. Moreover, BCR‐ABL1 transcript copies remained undetectable by RT‐PCR, 8 months after stopping bosutinib. The risk of secondary malignancy due to TKI has been controversial. It is reported that TKI induces irreversible chromosomal abnormalities or chromosome aberrations and inhibits the proliferation or function of T cells, B cells, and NK cells. These mechanisms of TKI may contribute to the development of secondary malignancy. There remains no consensus on the management of secondary lymphoma during TKI therapies. At present, the only alternative is to observe patients receiving TKI treatment cautiously and to treat secondary lymphoma in the same manner as de novo lymphoma.
In‐situ XAS Study of Catalytic N2O Decomposition Over CuO/CeO2 Catalysts
Authors: Zabilskiy Maxim , Arčon Iztok , Djinović Petar , Tchernychova Elena , Pintar Albin 
Published: January 2021

AbstractWe performed in‐situ XAS study of N2O decomposition over CuO/CeO2 catalysts. The Cu K‐edge and Ce L3‐edge XANES and EXAFS analyses revealed the dynamic and crucial role of Cu2+/Cu+ and Ce4+/Ce3+ ionic pairs during the catalytic reaction. We observed the initial formation of reduced Cu+ and Ce3+ species during activation in helium atmosphere at 400 °C, while concentration of these species decreased significantly during steady‐state nitrous oxide degradation reaction (2500 ppm N2O in He at 400 °C). In‐situ EXAFS analysis further revealed a crucial role of copper−ceria interface in this catalytic reaction. We observed dynamic changes in average number of Cu−Ce scatters under reaction conditions, indicating an enlarging of the interface between both copper and ceria phases, where electron and oxygen transfer occurs.
Green Synthesis of Zinc Oxide Nanoparticles by Justicia adhatoda Leaves and Their Antimicrobial Activity
Authors: Pachaiappan Rekha , Rajendran Saravanan , Ramalingam Gomathi , Vo Dai-Viet N. , Priya P. Mohana , Soto-Moscoso Matias 
Published: January 2021

AbstractZinc oxide is recognized as one of the best antimicrobial agents. Zinc oxide nanoparticles were fabricated through a green approach using zinc sulfate, zinc nitrate, and zinc acetate dihydrate as precursors and an extract of Justicia adhatoda leaves as a reducing agent. The synthesized zinc oxide nanoparticles were checked for their antimicrobial activity against the bacterial strains Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and the fungal strains Aspergillus niger, Aspergillus flavus, and Aspergillus fumigates. All three zinc oxide nanoparticles were found to inhibit the growth of microbes by the release of zinc ions and production of reactive oxygen species followed by destruction of microbes. Antimicrobial results of zinc oxide nanoparticles from the three different precursors were compared.
Photoinduced DNA Interstrand Cross‐Linking by 1,1′‐Biphenyl Analogues: Substituents and Leaving Groups Combine to Determine the Efficiency of Cross‐Linker
Authors: Fan Heli , Sun Huabing , Zhang Qi , Peng Xiaohua 
Published: January 2021

AbstractTwo series of 1,1′‐biphenyl analogues with various leaving groups (L=OAc, OCH3, OCHCH=CH2, OCH2Ph, SPh, SePh, and Ph3P+) were synthesized. Their reactivity towards DNA and the reaction mechanism were investigated by determining DNA interstrand cross‐link (ICL) efficiency, radical and carbocation formation, and the cross‐linking reaction sites. All compounds induced DNA ICL formation upon 350 nm irradiation via a carbocation that was generated from oxidation of the corresponding free radicals. The ICL efficiency and the reaction rate strongly depended on the combined effect of the leaving group and the substituent. Among all compounds tested, the high ICL efficiency (30–43 %) and fast reaction rate were observed with compounds carrying a nitrophenyl group and acetate (2 a), ether (2 b and 2 c), or triphenylphosphonium salt (2 g) as leaving groups. Most compounds with a 4‐methoxybenzene group showed similar DNA ICL efficiency (≈30 %) with a slow DNA cross‐linking reaction rate. Both cation trapping and free radical trapping adducts were detected in the photo activation process of these compounds, which provided direct evidence for the proposed mechanism. Heat stability study in combination with sequence study suggested that these photo‐generated benzyl cations alkylate DNA at dG, dA, and dC sites.
De Novo and Divergent Synthesis of Highly Functionalized Furans by Cascade Reactions of 2‐Hydroxy‐1,4‐diones with Nucleophiles
Authors: Liu Hai‐xuan , Ji Fei , Chen Yu , Gao Ya , Wang Jun‐ke , Zhang Ming‐zhi , Liu Fang , Sha Qiang 
Published: January 2021

AbstractHerein, a divergent synthesis of a variety of 2α‐ and 5α‐substituted furan derivatives from 2‐hydroxy‐1,4‐diones is reported. By using appropriate substrates and an acid catalyst, the reactions occurred selectively through cyclization/1,6‐conjugate addition or cyclization/Friedel–Crafts‐type cascade reactions. A broad range of nucleophilic reagents (>10 types for the 1,6‐conjugate addition for 5α substitution and >20 types for the Friedel–Crafts‐type cascade reaction for 2α substitution), including alcohols, amides, furan, thiophene, pyrrole, indole, phenols, and many others, can successfully participate in the reactions, providing a universal strategy for a diversity‐oriented synthesis of α‐substituted furan derivatives. Deuteriation experiments and DFT calculations were carried out to support the proposed reaction mechanisms. Antifungal activity experiments revealed that products with an indole or 4‐hydroxycoumarin core substituted at the 2α position showed moderate activities against Rhizoctorzia solani and Botrytis cinerea, respectively.
Beyond the Isoprene Pattern: Bifunctional Polyene Cyclizations
Authors: Feilner Julian M. , Haut Franz‐Lucas , Magauer Thomas 
Published: January 2021

AbstractPolyene cyclizations are capable of producing molecular complexity in a single step. While classical systems are limited to simple alkyl substitution patterns only, bifunctional polyenes take advantage of the unique reactivity of higher‐functionalized alkenes. Here, we highlight the potential of these variants for the synthesis of structurally complex polycycles involving unprecedented termination steps. We also want to provide a stimulus for the development of novel modes of cyclization that involve bifunctional units to enable efficient synthesis of yet inaccessible natural products.
Tuning the Regioselective Functionalization of Trifluoromethylated Dienes via Lanthanum‐Mediated Single C−F Bond Activation
Authors: Kumar Tarun , Yang Yan , Sghaier Sirine , Zaid Yassir , Le Goff Xavier F. , Rousset Elodie , Massicot Fabien , Harakat Dominique , Martinez Agathe , Taillefer Marc , Maron Laurent , Behr Jean‐Bernard , Jaroschik Florian 
Published: January 2021

AbstractThe development of new fluorine‐containing building blocks and their efficient synthetic access is currently a challenging research field. Herein, the highly regio‐ and stereoselective addition of a large range of aldehydes onto trifluoromethylated benzofulvenes was achieved using a simple La/I2/DIBAL‐Cl system via a selective C−F bond activation process. This versatile methodology provided homodienyl alcohols bearing a terminal CF2‐alkene with potential further applications, as shown by the dehydration to the first benzofulvenes carrying a difluorovinyl group. In addition, for certain electron‐poor aldehydes, unprecedented ipso substitution of the CF3 group in a diene was observed, which, according to DFT studies, is related to the presence of the large, Lewis‐acidic lanthanum metal.
Postsynthetic‐Modified PANI/MOF Composites with Tunable Thermoelectric and Photoelectric Properties
Authors: Xu Wenjuan , Zhao Yujie , Wang Huarui , Wang Hongfei , Pan Fangfang , Xu Ruixue , Hou Hongwei 
Published: January 2021

AbstractA 3D Co‐based metal–organic framework (Co‐MOF) with two kinds of large pores filled by free Co2+ ions and ligands was synthesized and characterized. To expand the MOF structure and conductivity, the free Co2+ ions and ligands were exchanged by conductive ionic liquid EtpyBr and photosensitive AgNO3 through single crystal‐to‐single crystal transformation, which produced structure‐changed 3D MOFs Co‐MOF‐Br and Co‐Ag‐MOF, which were characterized by single‐crystal X‐ray diffraction. Incorporating small quantities of doped polyaniline (PANI) with redox activity into the pores could further tune the stability and conductivity of the three MOFs. The PANI/MOFs all show outstanding electrical conductivity (≈10−2 S cm−1), and PANI/Co‐MOF‐Br has the largest p‐type Seebeck coefficient of 66.6 μV K−1. PANI/Co‐MOF‐Br and PANI/Co‐Ag‐MOF have 4 and 15 times higher photocurrent density compared with PANI/Co‐MOF, respectively. This work sheds light on the design of advanced electrically conductive 3D MOFs.
Merging Pd0/PdII Redox and PdII/PdII Non‐redox Catalytic Cycles for the Allylarylation of Electron‐Deficient Alkenes
Authors: Semba Kazuhiko , Ohta Naoki , Paulus Fritz , Ohata Masaki , Nakao Yoshiaki 
Published: January 2021

AbstractAn allylarylation of electron‐deficient alkenes with aryl boronates and allylic carbonates has been developed. This method allows access to a wide variety of carbon skeletons from readily available starting materials. Mechanistic studies indicate that this reaction is enabled by a cooperative catalysis based on merging Pd0/PdII redox and PdII/PdII non‐redox catalytic cycles.
Intramolecular Pyridinium Oxide Cycloadditions: Systematic Study of Substitution, Diastereoselectivity, and Regioselectivity
Authors: Lu Yi , Dey Patrick N. , Beaudry Christopher M. 
Published: January 2021

AbstractIntramolecular pyridinium oxide cycloadditions form complex polycyclic nitrogenous architectures. The diastereoselectivity and regioselectivity of pyridinium oxide cycloadditions was systematically investigated for the first time using complex substrates. Predictably high levels of diastereoselectivity and regioselectivity are observed, which can be attributed to minimization of steric (syn‐pentane) and torsional strain in the products. The reaction is reversible under the reaction conditions, and it is stereospecific with respect to the dipolarophile geometry.
Boosting the Capacitive Performance of Cobalt(II) Phthalocyanine by Non‐peripheral Octamethyl Substitution for Supercapacitors†
Authors: Li Minzhang , Ramachandran Rajendran , Wang Yu , Chen Qian , Xu Zong‐Xiang 
Published: January 2021

Main observation and conclusionIn this paper, pristine cobalt(II) phthalocyanine (CoPc) and non‐peripheral octamethyl substituted CoPc (N‐CoMe2Pc) are the focus of electrochemical investigation. CoPc and N‐CoMe2Pc nanorods (NR) were synthesized by a facile precipitation process from sublimated bulk phthalocyanine powders and their electrochemical properties were explored. Due to the large specific surface area, the capacitance performance of the nanorods was significantly higher than that of the sublimated powder sample. N‐CoMe2Pc powder exhibited better pseudocapacity compared with CoPc powder and CoPc NR, which is attributed to enhanced charge transfer rate and improved redox activity after the introduction of octamethyl substituents on phthalocyanine ring. The maximum specific capacitance value was achieved by N‐CoMe2Pc NR based electrode, exhibiting 210.2 F g–1 capacitance at 5 mV s–1 scan rate and 156.1 F g–1 at 0.25 A g‐1 current density, and also showing high efficiency and satisfactory retention. These results indicate that according to proper molecular design, N‐CoMe2Pc NR could be applied as the potential candidate for electrode material in supercapacitors.
Advances in Nucleoside and Nucleotide Analogues in Tackling Human Immunodeficiency Virus and Hepatitis Virus Infections
Authors: Ramesh Deepthi , Vijayakumar Balaji Gowrivel , Kannan Tharanikkarasu 
Published: January 2021

AbstractNucleoside and nucleotide analogues are structurally similar antimetabolites and are promising small‐molecule chemotherapeutic agents against various infectious DNA and RNA viruses. To date, these analogues have not been documented in‐depth as anti‐human immunodeficiency virus (HIV) and anti‐hepatitis virus agents, these are at various stages of testing ranging from pre‐clinical, to those withdrawn from trials, or those that are approved as drugs. Hence, in this review, the importance of these analogues in tackling HIV and hepatitis virus infections is discussed with a focus on the viral genome and the mechanism of action of these analogues, both in a mutually exclusive manner and their role in HIV/hepatitis coinfection. This review encompasses nucleoside and nucleotide analogues from 1987 onwards, starting with the first nucleoside analogue, zidovudine, and going on to those in current clinical trials and even the drugs that have been withdrawn. This review also sheds light on the prospects of these nucleoside analogues in clinical trials as a treatment option for the COVID‐19 pandemic.
Timing, number, and type of sexual partners associated with risk of oropharyngeal cancer
Authors: Drake Virginia E. , Fakhry Carole , Windon Melina J. , Stewart C. Matthew , Akst Lee , Hillel Alexander , Chien Wade , Ha Patrick , Miles Brett , Gourin Christine G. , Mandal Rajarsi , Mydlarz Wojciech K. , Rooper Lisa , Troy Tanya , Yavvari Siddhartha , Waterboer Tim , Brenner Nicole , Eisele David W. , D’Souza Gypsyamber 
Published: January 2021

BackgroundCase‐control studies from the early 2000s demonstrated that human papillomavirus–related oropharyngeal cancer (HPV‐OPC) is a distinct entity associated with number of oral sex partners. Using contemporary data, we investigated novel risk factors (sexual debut behaviors, exposure intensity, and relationship dynamics) and serological markers on odds of HPV‐OPC.MethodsHPV‐OPC patients and frequency‐matched controls were enrolled in a multicenter study from 2013 to 2018. Participants completed a behavioral survey. Characteristics were compared using a chi‐square test for categorical variables and a t test for continuous variables. Adjusted odds ratios (aOR) were calculated using logistic regression.ResultsA total of 163 HPV‐OPC patients and 345 controls were included. Lifetime number of oral sex partners was associated with significantly increased odds of HPV‐OPC (>10 partners: odds ratio [OR], 4.3 [95% CI, 2.8‐6.7]). After adjustment for number of oral sex partners and smoking, younger age at first oral sex (<18 vs >20 years: aOR, 1.8 [95% CI, 1.1‐3.2]) and oral sex intensity (>5 sex‐years: aOR, 2.8 [95% CI, 1.1‐7.5]) remained associated with significantly increased odds of HPV‐OPC. Type of sexual partner such as older partners when a case was younger (OR, 1.7 [95% CI, 1.1‐2.6]) or having a partner who had extramarital sex (OR, 1.6 [95% CI, 1.1‐2.4]) was associated with HPV‐OPC. Seropositivity for antibodies to HPV16 E6 (OR, 286 [95% CI, 122‐670]) and any HPV16 E protein (E1, E2, E6, E7; OR, 163 [95% CI, 70‐378]) was associated with increased odds of HPV‐OPC.ConclusionNumber of oral sex partners remains a strong risk factor for HPV‐OPC; however, timing and intensity of oral sex are novel independent risk factors. These behaviors suggest additional nuances of how and why some individuals develop HPV‐OPC.