bluuebunny/crossref_metadata_2025_split huggingface dataset:
Profiling the Nucleobase and Structure Selectivity of Anticancer Drugs and other DNA Alkylating Agents by RNA Sequencing
Authors: Sauter Basilius , Gillingham Dennis 
Published: May 2018

AbstractDrugs that covalently modify DNA are components of most chemotherapy regimens, often serving as first‐line treatments. Classically, the reactivity and selectivity of DNA alkylating agents has been determined in vitro with short oligonucleotides. A statistically sound analysis of sequence preferences of alkylating agents is untenable with serial analysis methods because of the combinatorial explosion of sequence possibilities. Next‐generation sequencing (NGS) is ideally suited for the broad characterization of sequence or structure selectivities because it analyzes many sequences at once. Herein, NGS is used to report on the chemoselectivity of alkylating agents on RNA and this technology is applied to the previously uncharacterized alkylating agent trimethylsilyl diazomethane.
Photoredox Reactions of Quinones
Authors: Ando Yoshio , Suzuki Keisuke 
Published: May 2018

AbstractPhotoredox reactions of quinones are reviewed, that enable C−H bond oxidation at the vicinity of the excited quinone carbonyl and concomitant reduction of the quinone under photoirradiation. Mechanistic insights on the benzo‐, naphtho‐, and anthraquinones are discussed. Also the potential utilities in organic synthesis are described.
Squalene‐Hopene Cyclase: Mechanistic Insights into the Polycyclization Cascades of Squalene Analogs Bearing Ethyl and Hydroxymethyl Groups at the C‐2 and C‐23 Positions
Authors: Kaneko Ikki , Terasawa Yuri , Hoshino Tsutomu 
Published: May 2018

AbstractSqualene‐hopene cyclase (SHC) catalyzes the conversion of squalene 1 into 6,6,6,6,5‐fused pentacyclic hopene 2 and hopanol 3. To elucidate the binding sites for the terminal positions of 1, four analogs, having the larger ethyl (Et) and the hydrophilic CH2OH groups at the 23E or 23Z positions of 1, were incubated with SHC. The analog with the Et group at the 23E position (23E‐Et‐1) yielded two tetra‐ and three pentacyclic products; however, the analog possessing the Et group at the 23Z position (23Z‐Et‐1) gave two hopene homologs and the neohopane skeleton, but no hopanol homologs. Hopene homolog (C31) was generated from 23E‐Et‐1 by deprotonation from 23Z‐Me (normal cyclization cascade). Intriguingly, the same homolog was also generated from the geometrical isomer 23Z‐Et‐1, indicating C−C bond rotation about the C‐21−C‐22 axis of the hopanyl cation and the more compact nature of the binding domain at 23Z compared with 23E. On the other hand, analogs with the CH2OH group gave novel hopane skeletons having 1‐formylethyl and 1‐hydroxyprop‐2‐en‐2‐yl residues at C‐21. Products bearing an aldehyde group were generated in higher yield from 23Z‐CH2OH‐1 (89 %), than from 23E‐CH2OH‐1 (26 %). The significant yield (26 %) of the aldehyde products from 23E‐CH2OH‐1 indicated that C−C bond rotation had occurred owing to the absence of hydrophobic interactions between the hydrophilic 23E‐CH2OH and its binding site. The polycyclization mechanisms of the four different analogs are discussed.
Intra‐ and Interparticle Heterogeneities in Solid Activators for Single‐Site Olefin Polymerization Catalysis as Revealed by Micro‐Spectroscopy
Authors: Velthoen Marjolein E. Z. , Meeldijk Johannes D. , Meirer Florian , Weckhuysen Bert M. 
Published: May 2018

AbstractMethylaluminoxane (MAO) is an activator for single‐site olefin polymerization catalysts. Structural characterization of MAO, and in particular the influence of its heterogenization on a silica support, is pivotal for the understanding and optimization of this versatile co‐catalyst. In this work, we demonstrate that by varying the MAO loading on a silica support, we can tune the single particle characteristics in terms of MAO distribution and consequent activity. At low MAO loading we reveal two possible intraparticle MAO distributions: a homogeneous and an Al‐shell type distribution. With increasing MAO loading, the interparticle MAO distribution becomes more homogeneous. Acidity probing measurements on the single particle level explain how a different intraparticle MAO distribution results in a different activity in metallocene activation. Al‐shell particles contain remaining silanol groups and a negligible amount of acid sites and are, therefore, considered inactive for metallocene activation. Only the solid activator particles with a homogeneous intraparticle MAO distribution contain a sufficient number of acid sites, capable of activating the deposited metallocenes.
Upconversion Cross‐Correlation Spectroscopy of a Sandwich Immunoassay
Authors: Lahtinen Satu , Krause Stefan , Arppe Riikka , Soukka Tero , Vosch Tom 
Published: May 2018

AbstractFluorescence correlation and cross‐correlation spectroscopy (FCS/FCCS) have enabled biologists to study processes of transport, binding, and enzymatic reactions in living cells. However, applying FCS and FCCS to samples such as whole blood and plasma is complicated as the fluorescence bursts of diffusing labels can be swamped by strong autofluorescence. Here we present cross‐correlation spectroscopy based on two upconversion nanoparticles emitting at different wavelengths on the anti‐Stokes side of a single excitation laser. This upconversion cross‐correlation spectroscopy (UCCS) approach allows us to completely remove all Stokes shifted autofluorescence background in biological material such as plasma. As a proof of concept, we evaluate the applicability of UCCS to a homogeneous sandwich immunoassay for thyroid stimulating hormone measured in buffer solution and in plasma.
Hydraulics and Operation Performance of TCDC‐Extractors
Authors: Grafschafter Annika , Rudelstorfer Georg , Siebenhofer Matthäus 
Published: May 2018

AbstractThe Taylor‐Couette disc contactor (TCDC) uses the hydrodynamic advantages of the rotating disc contactor (RDC) and Taylor‐Couette reactor. Drop size distribution, dispersed phase holdup and residence time distribution (RTD) of the TCDC in 0.1 m and 0.3 m diameter scale were determined. A correlation for the prediction of the Sauer mean diameter was validated experimentally for 0.3‐m scale. Analysis of RTD suggests application of the tank‐in‐series model. The number of vessels in series rises with increasing hydraulic load and decrease with increasing rate of rotation. The axial dispersion coefficient was determined in order to evaluate backmixing.
Verbrennungen – Eine Unterrichtseinheit für inklusiven Unterricht
Authors: Baumann Thomas , Kieserling Mats , Struckholt Sonja , Melle Insa 
Published: May 2018

AbstractMit der Ratifizierung der UN‐Behindertenrechtskonvention im Jahr 2009 hat sich Deutschland verpflichtet, ein inklusives Bildungssystem auf allen Ebenen zu etablieren, um Menschen mit Behinderungen Bildung ohne Diskriminierung zu gewähren. Die Realisierung eines inklusiven Chemieunterrichts stellt aktuell viele Chemielehrkräfte vor eine neue Aufgabe und Herausforderung. Das Prinzip des Universal Design for Learning (UDL) stellt ein Rahmenkonzept zur Planung und Gestaltung von Unterricht mit universeller Zugänglichkeit dar, das vor allem in den USA seit vielen Jahren etabliert ist. Im vorliegenden Beitrag wird das UDL kurz beschrieben und eine Unterrichtseinheit vorgestellt, die auf Basis des UDL konzipiert wurde.
Polymer‐Based White‐Light‐Emitting Electrochemical Cells with Very High Color‐Rendering Index Based on Blue‐Green Fluorescent Polyfluorenes and Red‐Phosphorescent Iridium Complexes
Authors: Nishikitani Yoshinori , Cho Tetsuyuki , Uchida Soichi , Nishimura Suzushi , Oyaizu Kenichi , Nishide Hiroyuki 
Published: May 2018

AbstractApplication of the concept of three‐color (red (R), green (G), and blue (B)) light‐mixing to obtain white light is the most suitable way to realize white‐light‐emitting devices with very high color‐rendering indices (CRI). White‐light‐emitting devices based on the three‐color‐mixing method could be used to create lighting and display technologies. Here, white‐light‐emitting electrochemical cells (LECs) with very high CRIs are reported, which were fabricated by using blend films composed of a fluorescent π‐conjugated polymer (FCP), poly(9,9‐dioctylfluorene‐co‐benzothiadiazole) (PFBT), and a phosphorescent iridium complex, [Ir(ppy)2(biq)]+(PF6)− (where (ppy)−=2‐phenylpyridinate and biq=2,2′‐biquinoline). The LECs fabricated with PFBT, the benzothiadiazole content of which is 0.01 mol %, showed blue electroluminescence (EL) emission originating from the fluorene segments and green EL emission from the benzothiadiazole units simultaneously. White LECs were then realized by adding red‐emitting Ir complexes as guest molecules to the blue‐green‐emitting PFBT. By optimizing the proportions of the PFBT and Ir complexes in the active layers (PFBT/[Ir(ppy)2(biq)]+(PF6)−=1:0.2 (mass ratio)), white‐light emission with Commission Internationale de l′Eclairage (CIE) coordinates of (0.29, 0.34) and a very high CRI value of 91.5 was achieved through RGB color‐mixing. It was noted that the emission mechanism was based on Förster resonance energy transfer and Dexter energy transfer from excited PFBT to [Ir(ppy)2(biq)]+(PF6)−. The utilization of LECs based on blue‐green FCPs and red Ir complexes looks very promising for the prospect of realizing white‐light‐emitting devices with very high CRIs.
Synthesis, Characterization and In Vitro Evaluation of Carbohydrate‐Containing Ruthenium Phthalocyanines as Third Generation Photosensitizers for Photodynamic Therapy
Authors: Ferreira Joana T. , Pina João , Ribeiro Carlos A. F. , Fernandes Rosa , Tomé João P. C. , Rodríguez‐Morgade M. Salomé , Torres Tomás 
Published: May 2018

AbstractPyridyl ligands with one ketal‐protected carbohydrate unit (glucofuranose, galactopyranose or mannofuranose) were coordinated to the axial positions of ruthenium phthalocyanines (RuPc) in order to target the macrocycles to tumor cells. The biocompatibility of the resulting photosensitizers (PS) was enhanced by increasing their solubility in water through their peripheral and/or axial functionalization with polyether chains (PEG). All compounds generated singlet oxygen, with peripherally unsubstituted phthalocyanines displaying higher 1O2 yields. In vitro assays using the human bladder cancer cell line HT‐1376 revealed that peripherally unsubstituted phthalocyanines were also more efficient in terms of cellular uptake and therefore, phototoxicity. The protected carbohydrate functional groups at the axial positions did not improve significantly the cellular uptake of PSs, although they increased their photodynamic efficiency. Overall, mixed RuPcs functionalized with one carbohydrate unit at one of the axial positions and two PEG units at the other axial site showed promising properties as photosensitizers for photodynamic therapy applications and low toxicity in the dark.
A common‐gate common‐source low noise amplifier based RF front end with selective input impedance matching for blocker‐resilient receivers
Authors: Ul Haq Faizan , Östman Kim B , Englund Mikko , Stadius Kari , Kosunen Marko , Koli Kimmo , Ryynänen Jussi 
Published: May 2018

SummaryThis paper presents an integrated wideband radio frequency front end with improved blocker resilience achieved through selective voltage attenuation at both input and output nodes of the low noise amplifier (LNA). The architecture differs from traditional LNA architectures where blockers are only attenuated at LNA output node. The proposed dual attenuation is attained by designing a low intrinsic input impedance common‐gate common‐source LNA with capacitive feedback, together with an N‐path filtering load. The capacitive feedback across the LNA ensures that the selective N‐path filtering profile at the LNA output is transferred to the LNA input nodes creating a selective input impedance. Consequently, the achieved front‐end input impedance is low at blocker frequencies and matched to the source impedance at the desired frequencies, creating the desired voltage attenuation for blockers. Further, a detailed theoretical analysis of proposed architecture is presented, which leads to clear design guidelines. Evaluated in a 28‐nm fully depleted silicon‐on‐insulator complementary metal oxide semiconductor (CMOS) process, front end is designed for wideband operation from 0.7 to 2.7 GHz. It consumes 11‐mA current from a 1‐V supply (excluding local oscillator (LO) buffering) and possesses a maximum noise figure of 5.1 dB. The front end demonstrates an out‐of‐band blocker compression point of −1.5 dBm and out‐of‐band IIP3 of +14 dBm at a 100‐MHz offset from LO frequency. In comparison with a traditional common‐gate common‐source LNA‐based front end with wideband input impedance matching, the proposed front end achieves 3.5‐dB improvement in the blocker compression point at a 100‐MHz offset from LO.
Multivariate theory‐based passivity criteria for linear fractional networks
Authors: Liang Guishu , Ma Long 
Published: May 2018

SummaryIn traditional linear network theory, the positive‐real (PR) criteria are widely used to judge the passivity of elements and networks in the light of the fact that there exists an equivalent relationship between the passivity and the PR property of their immittance functions (matrices). However, the equivalence will no longer hold when the fractional elements are introduced into the network, and the PR criteria are not suitable in complex frequency domain anymore. On the other hand, the rapid development of fractional‐order circuits and systems and the corresponding study in fractional circuit analysis and designs put forward an urgent requirement for the passivity criterion, which can tackle linear fractional networks. Hence, in this paper, we propose new passivity criteria for linear fractional networks by aid of generalized Tellegen's theorem and multivariable PR theory. By using the proposed criteria, the passivity of linear fractional networks can be judged, and the steps of the proposed criterion are illustrated by examples.
FAST: Rapid determinations of antibiotic susceptibility phenotypes using label‐free cytometry
Authors: Huang Tzu‐Hsueh , Tzeng Yih‐Ling , Dickson Robert M. 
Published: May 2018

AbstractSepsis, a life‐threatening immune response to blood infections (bacteremia), has a ∼30% mortality rate and is the 10th leading cause of US hospital deaths. The typical bacterial loads in adult septic patients are ≤100 bacterial cells (colony forming units, CFU) per ml blood, while pediatric patients exhibit only ∼1000 CFU/ml. Due to the low numbers, bacteria must be propagated through ∼24‐hours blood cultures to generate sufficient CFUs for diagnosis and further analyses. Herein, we demonstrate that, unlike other rapid post‐blood culture antibiotic susceptibility tests (ASTs), our phenotypic approach can drastically accelerate ASTs for the most common sepsis‐causing gram‐negative pathogens by circumventing long blood culture‐based amplification. For all blood isolates of multi‐drug resistant pathogens investigated (Escherichia coli, Klebsiella pneumoniae, and Acinetobacter nosocomialis), effective antibiotic(s) were readily identified within the equivalent of 8 hours from initial blood draw using <0.5 mL of adult blood per antibiotic. These methods should drastically improve patient outcomes by significantly reducing time to actionable treatment information and reduce the incidence of antibiotic resistance. © 2018 International Society for Advancement of Cytometry
Analgesic and anti‐inflammatory activities of epicatechin gallate from Bauhinia hookeri
Authors: Al‐Sayed Eman , Abdel‐Daim Mohamed M. 
Published: May 2018

Abstract

Hit, Lead & Candidate Discovery

The acetic acid‐induced writhing and hot plate models in mice were utilized to determine the analgesic effect of epicatechin gallate (ECG) isolated from Bauhinia hookeri. The anti‐inflammatory activity of ECG was determined using carrageenan‐induced paw edema model. The pro‐inflammatory mediators (PGE2, TNF‐α, IL‐1β, and IL‐6) were estimated in the plasma of different treatment groups. ECG was tested at doses of 100, 200, and 400 mg/kg p.o. and diclofenac sodium was used as a standard drug (100 mg/kg) in all experiments. ECG significantly (p < .001) suppressed the writhing response in mice. The inhibition percentages were 32, 52, and 62%, at the tested doses of ECG, respectively as compared to the positive control group receiving acetic acid only. Furthermore, ECG significantly (p < .001) increased the reaction time in hot plate model. The maximum analgesic effect was evident after 120 min. ECG demonstrated a significant anti‐inflammatory activity as evidenced by the inhibition of carrageenan‐induced paw edema (46, 50, and 58%, at the tested doses, respectively). This effect was persistent all over the experimental period. ECG produced a significant (p < .001) reduction in plasma PGE2 (by 27, 38, and 50%), TNF‐α (15, 33, and 41%), IL‐1β (17, 25, and 33%), and IL‐6 (22, 32, and 43%), at the tested doses, respectively. This study supports the use of ECG as both analgesic and anti‐inflammatory agent.
Research for leveraging food policy in universal eating disorder prevention
Authors: F. Rodgers Rachel , Sonneville Kendrin 
Published: May 2018

AbstractPolicy and legislation have emerged as important levers for universal prevention efforts in the context of eating disorders. However, to date, little attention has been paid to generating research that will inform opportunities to regulate the food environment, specifically the way that food is produced and marketed. The present paper aims to lay out a framework for research that will examine (1) the ways in which food industry may influence risk for eating disorders and (2) the impact of legislative efforts on eating disorder cognitions and behaviors. For these two pathways, specific examples of research that would serve to inform policy efforts aiming to decrease the risk for eating disorders by targeting the food environment are proposed. Overall, the present paper aims to issue a call for the eating disorder field to become involved in food policy and regulation.
Text‐mining as a methodology to assess eating disorder‐relevant factors: Comparing mentions of fitness tracking technology across online communities
Authors: McCaig Duncan , Bhatia Sudeep , Elliott Mark T. , Walasek Lukasz , Meyer Caroline 
Published: May 2018

AbstractObjectiveText‐mining offers a technique to identify and extract information from a large corpus of textual data. As an example, this study presents the application of text‐mining to assess and compare interest in fitness tracking technology across eating disorder and health‐related online communities.MethodA list of fitness tracking technology terms was developed, and communities (i.e., ‘subreddits’) on a large online discussion platform (Reddit) were compared regarding the frequency with which these terms occurred. The corpus used in this study comprised all comments posted between May 2015 and January 2018 (inclusive) on six subreddits—three eating disorder‐related, and three relating to either fitness, weight‐management, or nutrition. All comments relating to the same ‘thread’ (i.e., conversation) were concatenated, and formed the cases used in this study (N = 377,276).ResultsWithin the eating disorder‐related subreddits, the findings indicated that a ‘pro‐eating disorder’ subreddit, which is less recovery focused than the other eating disorder subreddits, had the highest frequency of fitness tracker terms. Across all subreddits, the weight‐management subreddit had the highest frequency of the fitness tracker terms' occurrence, and MyFitnessPal was the most frequently mentioned fitness tracker.DiscussionThe technique exemplified here can potentially be used to assess group differences to identify at‐risk populations, generate and explore clinically relevant research questions in populations who are difficult to recruit, and scope an area for which there is little extant literature. The technique also facilitates methodological triangulation of research findings obtained through more ‘traditional’ techniques, such as surveys or interviews.
Comparison of Carbon Stable Isotope and Fatty Acid Analyses for the Authentication of Perilla Oil
Authors: Kim Jinyeong , Yang Sehee , Jo Cheon‐Ho , Choi Jang‐Duck , Kwon Kisung , Ahn Sangdoo , Sook Chun Hyang , Hee Kim Byung 
Published: May 2018

Perilla oils distributed in Korea are authenticated by analyzing their 13C/12C isotope ratios (expressed as δ13C) or fatty acid compositions. No significant differences are found in the δ13C values of authentic (n = 27) and adulterated (n = 10) perilla oils, whereas the distributions of 11 fatty acids (FAs) are significantly different in these oils. By using orthogonal projections for latent structures discriminant analysis (OPLS‐DA) technique, the 18:2n‐6, and 18:3n‐3 content levels are determined to be the best variables for authenticating perilla oil. The authenticity of 7 out of 76 blind samples are identified through δ13C values, whereas using the 18:2n‐6 and 18:3n‐3 content levels can identify the authenticity of 66 blind samples. These results suggest that fatty acid analysis is a more useful procedure for determining the perilla oil authenticity. A blind trial shows that perilla oils adulterated with corn, soybean, or perilla‐flavored oil at concentrations ≥5 vol% can be distinguished.Practical applications: Public concern about economically motivated adulteration (EMA) of food is growing worldwide. Perilla oil is a targeted product for EMA in Korea due to its high retail price. This study provides the first evidence showing that 18:2n‐6 and 18:3n‐3 content levels can become new specifications and standards for perilla oils distributed in Korea.The present study develops a procedure for authenticating perilla oils on the basis of the range of linoleic and α‐linolenic acid content levels. The procedure can correctly identify perilla oils adulterated with corn, soybean, or perilla‐flavored oil at concentrations ≥5 vol%.
A simple strategy for dynamic substructuring: II. Experimental evaluation
Authors: Stefanaki Aikaterini , Sivaselvan M. V. , Weinreber Scot , Pitman Mark 
Published: May 2018

SummaryThis paper is on an extensive experimental evaluation program to explore the robustness of a new strategy dynamic substructuring. This strategy, in contrast to conventional approaches, decouples the substructuring controller from the physical subsystem, and consequently results in a simple, yet robust, implementation. The concept is presented in detail in a companion paper. A configuration consisting of a shake table and an active mass driver is used in the experimental program, and various factors such as dynamics of virtual subsystems used, modeling of the actuator, choice of control gain settings, and nonlinear effects in the actuator are investigated, leading to the conclusion that the proposed strategy results in robust performance.