bluuebunny/crossref_metadata_2025_split huggingface dataset:
Three New Polyacetylene Glycosides from the Roots of Heracleum dissectum and Their Triglyceride Accumulating Activities in 3T3‐L1 Cells
Authors: Gao Yang , Mi Jie , Zhang Chang‐Long , Zhang Xiao‐Qing , Peng Ya‐Jie , Bao He , Zhang Hai‐Long 
Published: November 2018

AbstractContinually phytochemical study of the roots of Heracleum dissectum had led to the isolation of three previously undescribed polyacetylene glycosides (1–3), together with seven known compounds, including one polyacetylene (8) and six coumarins (4–7 and 9–10) using diverse chromatographic methods. The structures of these three new compounds were characterized and identified as deca‐4,6‐diyn‐1‐yl β‐d‐glucopyranosyl‐(1→6)‐β‐d‐glucopyranosyl‐(1→2)‐β‐d‐glucopyranoside (1), (8Z)‐dec‐8‐ene‐4,6‐diyn‐1‐yl β‐d‐glucopyranosyl‐(1→6)‐β‐d‐glucopyranosyl‐(1→2)‐β‐d‐glucopyranoside (2), and (8E)‐dec‐8‐ene‐4,6‐diyn‐1‐yl β‐d‐glucopyranosyl‐(1→6)‐β‐d‐glucopyranosyl‐(1→2)‐β‐d‐glucopyranoside (3) based on their physicochemical properties and extensive analyses of various spectroscopic data. Their triglycerides accumulating activities were assayed and the results showed that the three new polyacetylene glycosides (1–3) exhibited triglyceride accumulating activities in 3T3‐L1 adipocytes.
Cell‐Compatible Nanoprobes for Imaging Intracellular Phosphatase Activities
Authors: Wang Jiaqing , Zhou Jie , He Hongjian , Wu Difei , Du Xuewen , Xu Bing 
Published: November 2018

AbstractPhosphatases play an important role in cell biology, but only a few probes are suitable for selectively imaging phosphatase activity in live cells, because the current probes require cell fixation or exhibit considerable cytotoxicity. Herein, we show that conjugating a d‐peptide to a quinazolinone derivative generates cell‐compatible, biostable probes for imaging the phosphatase activity inside live cells. Moreover, our results show that inhibiting ectophosphatases is a critical factor for imaging intracellular phosphatases. As the first example of using selective inhibitors to ensure intracellular function of molecular probes, this work illustrates a facile approach to design molecular probes for profiling the activities of enzymes in a spatial, selective manner in a complicated environment.
Molybdenum‐Based Carbon Hybrid Materials to Enhance the Hydrogen Evolution Reaction
Authors: Bae Seo‐Yoon , Jeon In‐Yup , Mahmood Javeed , Baek Jong‐Beom 
Published: November 2018

AbstractHydrogen is considered a future energy carrier that could improve energy storage of intermittent solar/wind power to solve energy and environmental problems. Based on such demand, development of electrocatalysts for hydrogen generation has been actively pursued. Although Pt is the most efficient catalyst for the hydrogen evolution reaction (HER), it has limits for widespread application, mainly its low abundance and high cost. Thus, developing an efficient catalyst from non‐precious metals that are abundant and inexpensive remains an important challenge to replacement of Pt. Transition metals have been considered possible candidates to replace Pt‐based catalysts. In this review, among the transition metals, we focus on recently developed molybdenum–carbon (Mo–C) hybrid materials as electrocatalysts for HER. In particular, the synthesis strategy for Mo–C hybrid electrocatalysts and the role of various carbon nanocomposites in Mo–C hybrid systems are highlighted.
Reversible Multicolor Photochromism of Dihydroazulene Crystals
Authors: Liepuoniute Ieva , Commins Patrick , Karothu Durga Prasad , Schramm Stefan , Hara Hideyuki , Naumov Panče 
Published: November 2018

AbstractThe photochemical conversion of 1,8a‐dihydroazulene‐1,1‐dicarbonitrile (DHA) to vinylheptafulvene (VHF) is a positive T‐type photoswitch that is well understood in solution, but has not been explored in the solid state. Upon excitation with UV light, DHA is converted into VHF in the solid state, with a distinct color change from yellow to deep‐red, and retention of crystallinity. The structure of the ring‐opened product was assigned to syn‐VHF using variable‐temperature infrared spectroscopy, and determined by X‐ray photodiffraction in a crystal enriched with the product by two‐photon excitation. A radical pathway becomes an observable photoreaction channel at low temperatures, and includes a strongly colored, short‐lived diradical intermediate.
Thermally Reduced Graphene/MXene Film for Enhanced Li‐ion Storage
Authors: Xu Shuaikai , Dall'Agnese Yohan , Li Junzhi , Gogotsi Yury , Han Wei 
Published: November 2018

AbstractTwo‐dimensional transition‐metal carbides called MXenes are emerging electrode materials for energy storage due to their metallic electrical conductivity and low ion diffusion barrier. In this work, we combined Ti2CTx MXene with graphene oxide (GO) followed by a thermal treatment to fabricate flexible rGO/Ti2CTr film, in which electrochemically active rGO and Ti2CTr nanosheets impede the stacking of layers and synergistically interact producing ionically and electronically conducting electrodes. The effect of the thermal treatment on the electrochemical performance of Ti2CTx is evaluated. As anode for Li‐ion storage, the thermally treated Ti2CTr possesses a higher capacity in comparison to as‐prepared Ti2CTx. The freestanding hybrid rGO/Ti2CTr films exhibit excellent reversible capacity (700 mAh g−1 at 0.1 Ag−1), cycling stability and rate performance. Additionally, flexible rGO/Ti3C2Tr films are made using the same method and also present improved capacity. Therefore, this study provides a simple, yet effective, approach to combine rGO with different MXenes, which can enhance their electrochemical properties for Li‐ion batteries.
Deformylated Gramicidin A and Its Derivatives Showing High Antimicrobial Activity and Low Hemolytic Toxicity
Authors: Haoyang Wei‐Wei , Zhang Min , Hou Jun‐Li 
Published: November 2018

Summary of main observation and conclusionGramicidin A is a natural peptide, which shows high antimicrobial activity to Gram‐positive bacteria. However, the hemolytic toxicity prevents its therapeutic usage. We demonstrated that by simply removing the formyl group at the N terminus, the hemolytic toxicity of the peptide could be obviously decreased. The deformylated gramicidin A (1) could efficiently insert into the lipid bilayer to form transmembrane channels. The peptide can also selectively insert into the membrane of Gram‐positive bacteria but not that of erythrocytes, leading to its high antimicrobial activity and very low hemolytic toxicity. The derivation of1could be achieved by decoration at the terminal NH2group, which also produced peptides showing high activity and low hemolytic toxicity. This derivation method provided us with an efficient strategy to build a library for future activity and cytotoxicity screeningin vitroandin vivo.
A geometric approach to harmonic color palette design
Authors: Lara‐Alvarez Carlos , Reyes Tania 
Published: November 2018

AbstractWe address the problem of finding harmonic colors, this problem has many applications, from fashion to industrial design. The proposed approach enables the evaluations and generation of color combinations incrementally. To solve this problem, we consider that colors follow normal distributions in tone (chroma and lightness) and hue. The proposed approach relies in the International Commission on Illumination standard for representing colors and evaluates proximity. Other approaches to this problem use a set of rules. Experimental results show that lines with specific parameters—angles of inclination and distance from the reference point—are preferred over others and that uncertain line patterns outperform nonlinear patterns.
High‐Throughput Analysis of Behavior Under the Control of Optogenetics in Caenorhabditis elegans
Authors: Yu Alex J. , McDiarmid Troy A. , Ardiel Evan L. , Rankin Catharine H. 
Published: November 2018

AbstractIn this unit, we describe an inexpensive and versatile method for optogenetic stimulation of a large population of genetically engineered Caenorhabditis elegans worms while quantitatively analyzing behavior. A custom light‐emitting diode light source is used to deliver blue‐light stimuli, causing direct depolarization of neurons expressing the light‐gated cation channel Channelrhodopsin‐2, which in turn evokes behavioral responses. The behavioral responses are recorded by a high‐throughput machine vision–based tracking system, the Multi‐Worm Tracker, for detailed analysis. This approach allows researchers to bypass technical obstacles to simultaneously deliver uniform stimuli to a large number of freely behaving animals and investigate the neural underpinnings of behavior. © 2018 by John Wiley & Sons, Inc.
An Industrial Applicable Method for the Synthesis of N‐alkylated Maleimides Based on Fatty Amines
Authors: Schmidt Philipp , Eschig Steven 
Published: November 2018

A simple and economic two step synthesis of N‐alkylated maleimides with repeatable recycling of recovered starting materials from the second step is developed. In the first step, maleic anhydride is reacted with different natural mixtures of bio‐based fatty amines to give the corresponding maleic acid alkyl amides. The formation of the 5‐membered maleimide‐rings is achieved via acid‐catalyzed intramolecular condensation. However, in this step only 50–64% of the used alkyl amides are converted toward the required N‐alkylated maleimides. The novelty of our approach is the continuous recycling of recovered non‐converted amides for additional cyclization steps. These steps are repeated several times, whereby the yields of maleimides for each step leveled off at 46–50%.Practical Applications: Click reactions have become more and more prominent in the field of material science. A relevant used example is the [4 + 2]‐cycloaddition of maleimides and furans, whereby both moieties can be attached to the polymer backbone. This is a promising approach for the introduction of new functionalities to a polymer by a simple addition reaction. For this purpose a polymer, which contains furan groups and a functionalized maleimide are needed. For example, the use of fatty acid based maleimides allows the introduction of hydrophobic properties to a furan‐functionalized polymer, due to their long alkyl chain. However, the functional group of the maleimide can be varied to introduce other properties, like antimicrobial, hydrophilic or combinations thereof. This technique is interesting for coatings and allows the adaption of surface properties in a wide range. Moreover, maleimides can be used as polymerizable monomers to synthesize high performance macromolecular systems like polymers with high thermal stability.Synthesis of fatty acid based maleimides starting from maleic anhydride and fatty amines. This technique is interesting for coatings and allows the adaption of surface properties in a wide range. Moreover, maleimides can be used as polymerizable monomers to synthesize high performance macromolecular systems like polymers with high thermal stability.
Variance and skew risk premiums for the volatility market: The VIX evidence
Authors: Da Fonseca José , Xu Yahua 
Published: November 2018

AbstractWe extract variance and skew risk premiums from volatility derivatives in a model‐free way and analyze their relationships along with volatility index and equity index returns. These risk premiums can be synthesized through option trading strategies. Using a time series of option prices on the VIX, we find that variance swap excess return can be partially explained by volatility index and equity index excess returns while these latter variables carry little information for the skew swap excess return. The results sharply contrast with those obtained for the equity index option market underlining very specific characteristics of the volatility derivative market.
Do country risk and ﬁnancial uncertainty matter for energy commodity futures?
Authors: Lee Chien‐Chiang , Lee Chi‐Chuan , Lien Donald 
Published: November 2018

AbstractUsing an instrumental variable quantile regression technique, this paper assesses whether country risk and financial uncertainty exert an impact on energy commodity futures prices under different commodity conditional return distributions over the period from January 1994 to July 2017. We also discuss whether the correlations change with different dimensions of country risk, that is economic, financial, and political. The results reveal that country risk and financial stress do have a significant impact on energy commodity returns of futures contracts with different maturities, but their direction, intensity, and significance differ, caused by the distinct market situations and divergent channels of country risk.
Common fragile site instability in normal cells: Lessons and perspectives
Authors: Palumbo Elisa , Russo Antonella 
Published: November 2018

AbstractMechanisms and events related to common fragile site (CFS) instability are well known in cancer cells. Here, we argue that normal cells remain an important experimental model to address questions related to CFS instability in the absence of alterations in cell cycle and DNA damage repair pathways, which are common features acquired in cancer. Furthermore, a major gap of knowledge concerns the stability of CFSs during gametogenesis. CFS instability in meiotic or postmeiotic stages of the germ cell line could generate chromosome deletions or large rearrangements. This in turn can lead to the functional loss of the several CFS‐associated genes with tumor suppressor function. Our hypothesis is that such mutations can potentially result in genetic predisposition to develop cancer. Indirect evidence for CFS instability in human germ cells has been provided by genomic investigations in family pedigrees associated with genetic disease. The issue of CFS instability in the germ cell line should represent one of the future efforts, and may take advantage of the existence of sequence and functional conservation of CFSs between rodents and humans.
Reaction of arynes with trifluoroacetylated β‐diketones: Novel formation of isocoumarins and phenanthrenes
Authors: Okuma Kentaro , Tanabe Yukiko , Fukami Takuto , Ishibashi Yuto 
Published: November 2018

AbstractPolysubstituted isocoumarins were synthesized by the reaction of substituted 2‐(trimethylsilyl)aryl triflates with trifluoromethylated β‐diketones in the presence of CsF. The reaction proceeded through carbon‐carbon bond insertion of aryne and intramolecular cyclization to form intermediates of alcohol anions, which extruded trifluoromethyl anion to afford isocoumarins. By using CuBr as a catalyst, 2 eq. of aryne reacted with β‐diketones to afford phenanthrenes and 1,2‐diarylethanones. Although reaction of 2‐(trimethylsilyl)phenyl triflate with 1,1,1‐trifluoro‐4′‐methylbenzoylacetone in the presence of CsF gave 3‐(4′‐methylphenyl)isocoumarin in 67% yield, addition of 0.2 eq. of CuCN resulted in the formation of 9‐(4‐methylbenzoyl)‐10‐trifluoromethylphenanthrene in 35% yield.
Surgical resection of carotid body tumors with versus without preoperative embolization: Retrospective case‐control study
Authors: Liu Jianlin , Li Yanzi , Yang Lin , Cai Hui 
Published: November 2018

AbstractBackgroundThe purpose of this study was to investigate the outcomes of surgical resection of carotid body tumors with and without preoperative embolization.MethodsThere were 31 patients who underwent surgical resection combined with preoperative embolization (SRE group), and 27 patients who underwent conventional surgical resection (SR group); all clinical data were included and reviewed.ResultsThere was no difference in the approach for carotid reconstruction in either group (P > .05). The mean surgical time (110.65 ± 35.77 minutes vs 188.33 ± 66.44 minutes) and intraoperative blood loss (140.32 ± 57.12 mL vs 396.43 ± 272.82 mL) were significantly less in the SRE group (P < .05). The volume of blood transfusions required (475 ± 301.18 mL vs 0 mL) and incidence rate of total complications (33.3% vs 9.7%) were higher in the SR group (P < .05). However, the length of hospital stay was similar in both groups (P > .05).ConclusionOur results demonstrate that preoperative embolization of a carotid body tumor can reduce blood loss and complications and improve tumor excision.
Oral and pharyngeal cancer risk associated with occupational carcinogenic substances: Systematic review
Authors: Awan Kamran Habib , Hegde Rachana , Cheever Val J , Carroll William , Khan Shahrukh , Patil Shankargouda , Warnakulasuriya Saman 
Published: November 2018

AbstractBackgroundOral and pharyngeal cancers (OPC) represent the seventh most common type of cancer and the seventh leading cause of deaths by cancer worldwide. Few studies have assessed the occupational exposure risks associated with OPC and in many cases the results are conflicting. The aim of this study was to determine, through a systematic review, the association of OPC and exposure to different occupational carcinogenic substances.MethodsThe addressed focused question was “Is there an association of occupational carcinogenic substances with OPC?” PubMed, MEDLINE, EMBASE, and ISI Web of Science databases were searched between January 1995 up to and including July 2016 using the keywords “oral cancer,” “pharyngeal cancer,” “pharyngeal neoplasms,” “oral neoplasms,” “occupational disease,” “occupational exposure,” and “occupational risk factor” in various combinations. Letters to the Editor, review articles, case reports, and unpublished articles were excluded.ResultsFourteen original articles were included. Majority of the studies were conducted in European countries and used a case‐control design. The results showed a significant association between formaldehyde, wood dust, coal dust, asbestos, welding fumes, and risk of developing OPC, while marginal association was observed with metal and leather dust. No associated risk was observed for textile fibers.ConclusionThere is some evidence to suggest associations of occupational substances with OPC, particularly in the pharynx. Future well‐designed studies are required to confirm or rule out with confidence the associated exposure risk of these substances.
Clinical guidelines—the challenges and opportunities: What we have learned from the case of misoprostol for postpartum hemorrhage
Authors: Morris Jessica L. , Khatun Samia 
Published: November 2018

AbstractObjectiveTo establish whether national guidelines for postpartum hemorrhage (PPH) reflect new scientific evidence on misoprostol, and determine the challenges faced in their implementation.MethodsA web‐based survey was sent by email to 130 national societies of obstetrics and gynecology (FIGO Member Associations) in 2016. The survey, composed of 18 questions, covered national guidelines on PPH with particular reference to misoprostol, the creation of national guidelines, and challenges to implementation.ResultsCompleted surveys were received from 69 societies, for a 53% response rate. The key findings were that many countries lacked comprehensive, up‐to‐date, evidence‐based national guidelines providing guidance on misoprostol use; recommended regimens were very different in the national guidelines as well as between international and regional guidelines that are most often used as referencing documents; and there are a variety of challenges to implementation of guidelines.ConclusionThere is a need, especially in countries with high maternal mortality, to establish mechanisms that ensure the existence of up‐to‐date, comprehensive, evidence‐based guidelines on PPH. This can be difficult given conflicting guidance at the international level. Regional and international societies should prioritize clinical updates and ensure their dissemination and implementation.
Indwelling ports for prophylactic RBC exchanges in sickle cell patients: Comparison of bard and vortex ports
Authors: Lawicki Shaun , Craig‐Owens Laura , Bream Peter R. , Eichbaum Quentin 
Published: November 2018

AbstractIntroductionRed blood cell exchange (RCE) procedures are commonly used for stroke prevention in sickle cell disease (SCD) patients. We compared two different dual lumen ports used for RCE because differences between the port and catheter design may lead to functional variance.MethodsWe reviewed the RCE parameters of SCD patients following implantable port placement encountered at a single institution. Five Vortex and four Bard ports were used and compared. Patients were followed for 1‐24 exchange procedures over 3‐26 months performed between 2013 and 2015.ResultsNine patients underwent 124 RCE procedures with no failures. A total of 74 exchanges used Vortex ports with a mean flow rate of 45.2 mL/min while 50 exchanges used Bard ports with a mean flow rate of 42.1 mL/min which was a significant difference (P = .002). A total of 85 exchanges with tPA administration preprocedure had a mean flow rate of 43.8 mL/min while 39 exchanges without had a mean flow rate of 45.4 mL/min which was not a significant difference (P = .19).ConclusionBoth the Bard and Vortex ports functioned well during our study period with no treatment failures, no significant complications requiring removal or replacement, and adequate mean flow rates. While the difference in mean flow rates was statistically significant between Vortex and Bard ports, there may not be a practical difference in performance. There also does not appear to be a significant benefit in flow rates with preprocedure tPA. We conclude that both ports may be a satisfactory choice for vascular access in SCD patients expected to undergo regularly scheduled RCE.
Single‐needle: an effective alternative to dual‐needle peripheral access in therapeutic plasma exchange
Authors: Doggett Betty M. , Session‐Augustine Nellie , Roig Joseph , Strunk Matthew , Valiyaparambil Shiney , Sarode Ravi , De Simone Nicole 
Published: November 2018

AbstractApheresis treatments, which involve the removal of a component of blood, generally require one access and one return line to continuously draw and return blood into the extracorporeal circuit. At our center, we prefer to use peripheral venous access to avoid central line‐related complications, especially infection. Motivated by patient‐centered care, the single‐needle (SN) option for therapeutic plasma exchange (TPE) offered on the Spectra Optia (Terumo BCT, Lakewood, CO) was evaluated. Five patients underwent procedures using both SN and dual‐needle (DN) plasma exchange procedures using the Spectra Optia. TPE procedures ran a median of 51 (range:10‐102) minutes longer using the SN‐TPE option. Inlet flow rates, plasma removal efficiency, and incidence of citrate reactions were similar between SN‐ and DN‐procedures. Patients reported great satisfaction with SN‐TPE.