bluuebunny/crossref_metadata_2025_split huggingface dataset:
Regioselective Iron‐Catalysed Cross‐Coupling Reaction of Aryl Propargylic Bromides and Aryl Grignard Reagents
Authors: Manjón‐Mata Inés , Quirós M. Teresa , Buñuel Elena , Cárdenas Diego J. 
Published: November 2019

AbstractAn iron‐catalysed Kumada‐type cross‐coupling reaction between aryl substituted propargylic bromides and arylmagnesium reagents has been developed. Propargylic coupling products were the main or only outcome, and propargyl/allene regioselectivity was shown to depend on the electronic nature of the substituents on the triple bond of the substrate and on the arylmagnesium halide. Best selectivities were observed when electron donating substituents were present in either reagent. The process is stereoespecific, occurs with configuration inversion and no carbon‐based radicals seem to be involved in the mechanism.magnified image
Measuring Human Water Needs
Authors: Wutich Amber , Rosinger Asher Y. , Stoler Justin , Jepson Wendy , Brewis Alexandra 
Published: November 2019

AbstractWater connects the environment, culture, and biology, yet only recently has it emerged as a major focus for research in human biology. To facilitate such research, we describe methods to measure biological, environmental, and perceptual indicators of human water needs. This toolkit provides an overview of methods for assessing different dimensions of human water need, both well‐established and newly‐developed. These include: (a) markers of hydration (eg, urine specific gravity, doubly labeled water) important for measuring the impacts of water need on human biological functioning; (b) methods for measuring water quality (eg, digital colorimeter, membrane filtration) essential for understanding the health risks associated with exposure to microbiological, organic, metal, inorganic nonmental, and other contaminants; and (c) assessments of household water insecurity status that track aspects of unmet water needs (eg, inadequate water service, unaffordability, and experiences of water insecurity) that are directly relevant to human health and biology. Together, these methods can advance new research about the role of water in human biology and health, including the ways that insufficient, unsafe, or insecure water produces negative biological and health outcomes.
Narrow molecular weight margins for the thermogelling property of polyester–polyether block copolymers in aqueous solutions
Authors: Garner John , Hadar Justin , Skidmore Sarah , Jessmon Faye , Immel Rebecca , Tyler Amie , Park Kinam 
Published: November 2019

ABSTRACTPolyester–polyether block copolymers with thermogelling properties have been widely used in pharmaceutical and biomedical applications for their biocompatibility and degradation to nontoxic components. The biodegradable polymers, such as poly(lactide‐co‐glycolide) and poly(lactide‐co‐caprolactone) (PLCL), have been used as the polyester block. The most commonly used polyether has been poly(ethylene glycol) (PEG). The thermogelling polymers dissolve in cold water, but become a semisolid gel at higher temperatures, for example, body temperature. This thermogelling property, however, occurs only within very narrow molecular weight ranges of the polyester at given polyether blocks. Only a few hundred Dalton differences in the polyester block can turn a thermogelling polymer into a water‐insoluble polymer. This study describes the hydrophilic and hydrophobic block sizes for endowing the thermogelling property and a simple, water‐free, synthesis of new thermogelling PLCL–PEG–PLCL triblock polymers. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48673.
Carbon nanotube localization at interface in cocontinuous blends of polyethylene and polycarbonate
Authors: Nishikawa Riho , Tamaki Kakeharu , Notoya Osamu , Yamaguchi Masayuki 
Published: November 2019

ABSTRACTA new technique to show good electroconductivity was proposed using carbon nanotube (CNT) localization in cocontinuous immiscible polymer blends comprising ultrahigh‐molecular‐weight polyethylene (UHMWPE) and polycarbonate (PC). When UHMWPE was added to PC/CNT in the molten state in an internal mixer, CNTs started moving to the UHMWPE phase. However, CNTs require a long time to diffuse into the UHMWPE phase owing to a low diffusion constant. Consequently, they remain at the interface between PC and UHMWPE. When the blends have cocontinuous structure, the localized CNTs at the phase boundary act as a conductive path, leading to a good electroconductivity. Although a similar morphology is obtained by adjusting the balance of interfacial tensions among polymers and CNT, it is difficult to find a system showing appropriate interfacial tensions. As the present method is applicable to various polymer blends, it will be an important technique to prepare a conductive nanocomposite. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 137, 48676.
Investigation of mechanical properties of graphene decorated with graphene quantum dot‐reinforced epoxy nanocomposite
Authors: George Manuel , Mohanty Akash 
Published: November 2019

ABSTRACTIn this investigation, the mechanical properties such as compression, impact, and flexural properties of graphene decorated with graphene quantum dots (GDGQD) epoxy composites with concentration of GDGQD ranging from 0.25 to 1 wt % were studied. Ideal mechanical properties are obtained by systematically varying the filler weight in the epoxy matrix. The morphological studies of GDGQD have been characterized using transmission electron microscope, X‐ray diffraction, and Fourier transform infrared technique. The compression, impact, and flexural strengths were enhanced effectively by the GDGQD loading. With the addition of 0.75 wt % of GDGQD, the compressive strength, compressive modulus, flexural strength, and flexural modulus of the composites were improved by 22, 29, 31, and 63%, respectively. Also an improvement in impact strength of 102% for 0.75 wt % GDGQD epoxy sample was also obtained. Examination of fractured test specimens was performed with scanning electron microscope. The enhancement in the mechanical properties is due to the better stress transfer that is attributed by enhanced interfacial bonding between GDGQDs and the epoxy. Using the GDGQD aspect ratio in the two‐dimensional randomly oriented filler modified Halpin–Tsai model, the theoretical flexural modulus for the GDGQD/epoxy composites has been established. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 137, 48680.
A novel treatment strategy using indocyanine green for transarterial chemoembolization in BCLC stage C hepatocellular carcinoma
Authors: Mei Jie , Li Shao‐Hua , Wang Qiao‐Xuan , Zhong Xiao‐Ping , Lu Liang‐He , Kan Anna , Wei Wei , Guo Rong‐Ping 
Published: November 2019

AbstractPurposeThe aim of our study was to propose a strategy based on indocyanine green (ICG) (SBI) to provide better clinical guidelines for transarterial chemoembolization (TACE) treatments for Barcelona clinic liver cancer (BCLC) stage C hepatocellular carcinoma (HCC) patients.Materials and MethodsFrom October 2005 to December 2012, 112 BCLC stage C HCC patients initially treated with TACE were investigated, randomly divided into a training cohort (n = 79) and validation cohort (n = 33). In training group, the patients were grouped based on their 15 minutes ICG retention rate (ICG R15), different chemo drugs and dose of lipidol in TACE. Overall survival (OS) and progression‐free survival (PFS) were analyzed in subgroups. Strategy based on ICG was built and verified in validation group.ResultsFor those patients with ICG R15 values >10%, the lipiodol ≤10 mL group showed better survival than the lipiodol >10 mL group. For those patients with ICG R15 values ≤10%, the group that received triple‐drug chemotherapy treatments with lipiodol diameter ratio values between 1 and 3 showed better survival than the other group. Patients who conformed with the SBI had better survival times than those who did not conform with the SBI, in both the training cohort (median OS 10.3 vs 5.1 months; P < .001; median PFS, 3.3 vs 2.1 months; P = .006) and the validation cohort (median OS 8.9 vs 7.1 months; P = .087; median PFS, 6.6 vs 2.3 months; P < .001).ConclusionsThe SBI is suitable and may provide survival benefits for TACE treatments in BCLC stage C HCC patients.
Doxorubicin‐associated takotsubo cardiomyopathy in a patient with adult T‐cell leukemia/lymphoma
Authors: Mubarak Ghassan , Haddadin Michael , Samra Bachar , Luhrs Carol , Taiwo Evelyn 
Published: November 2019

AbstractThis case highlights the first reported association of doxorubicin with takotsubo cardiomyopathy (TC) presenting as cardiogenic shock during the first continuous infusion in a patient with adult T‐cell leukemia/lymphoma. We aim to raise awareness to recognize and distinguish between irreversible doxorubicin‐associated cardiomyopathy and reversible doxorubicin‐associated TC in patients with cancer.
Changes in Active Sites on Nitrogen‐Doped Carbon Catalysts Under Oxygen Reduction Reaction: A Combined Post‐Reaction Characterization and DFT Study
Authors: Jain Deeksha , Zhang Qiang , Hightower Jonathan , Gustin Vance , Asthagiri Aravind , Ozkan Umit S. 
Published: November 2019

AbstractNitrogen‐doped carbon nanostructures (CNx) have been shown to be promising catalysts to replace Pt‐based materials for oxygen reduction reaction (ORR) in PEM fuel cell cathodes. This work reports the use of a combination of post‐reaction X‐ray photoelectron spectroscopy (XPS) and density functional theory (DFT) aimed at examining changes to the nitrogen species in CNx after potential application in an oxygen saturated acidic electrolyte. The results hence obtained reveal interesting changes to the pyridinic, quaternary and pyridinic N+O− binding energy envelopes as a result of protonation of sites and formation of ORR intermediates after the CNx electrodes were subjected to electrochemical potential holds in the kinetic and mass transfer limited regimes of the ORR cyclic voltammogram of the catalyst.
Underpotential Deposition of Copper Clusters on Sulfur and Nitrogen Co‐Doped Graphite Foam for the Oxygen Reduction Reaction
Authors: Xu Jingsong , Li Rui , Zeng Rongguang , Li Yingru , Pan Qifa , Zhong Hang , Chen Jun 
Published: November 2019

AbstractIn this study, we successfully fabricated approximately 1 nm copper clusters on sulfur and nitrogen co‐doped graphite foam (SNGF) by using an electrodeposition method. The introduction of sulfur dopants enhances the metal‐support interaction and, thus, allows the application of the underpotential deposition (UPD) technique on graphite foam. Furthermore, the strong S−Cu binding leads to the preferential formation and firm anchoring of Cu nuclei on monodispersed S sites. The controllable growth of Cu nuclei into Cu clusters is achieved by controlling the deposition amount by adjusting the electrochemical parameters. As an example, the supported Cu clusters were utilized towards oxygen reduction reaction catalysis, exhibiting a high catalytic activity and a long‐term durability. Remarkably, this strategy is promising for developing a general method to prepare other metal clusters (e. g. Ag clusters).
Analytical methodologies for the enantiodetermination of citalopram and its metabolites
Authors: Budău Monica , Hancu Gabriel , Rusu Aura , Muntean Daniela Lucia 
Published: November 2019

AbstractCitalopram (CIT) is a highly selective serotonin reuptake inhibitor (SSRI) frequently used in the treatment of major depressive disorders. It has a chiral centre in its structure and is used in therapy both as a racemic mixture (R,S‐CIT) and a pure enantiomer (S‐CIT). The differences between the pharmacokinetic and pharmacological profiles of the two enantiomers are well established. Consequently, the development of new efficient chiral analysis methods for their enantiomeric separation is a topic of great actuality. CIT metabolism is stereoselective as it is metabolized in chiral active metabolites, which retain considerable SSRI activity and contribute to the pharmacological effect. Chiral analytical methods are employed for the determination of enantiomeric ratio in pharmaceutical preparations and for monitoring the enantiomer levels in biological samples for therapeutic and toxicologic purposes. The current study reviews the published literature for the chiral analysis of CIT and its metabolites based on chromatographic and electrophoretic methods coupled with UV, fluorescence and mass spectrometry detectors.
Chemical Bonds and Periodic System: The Use of didactically refined periodic systems (PSE3 – Periodic System on 3 levels and the Periodic Table of the basic particles and forces) in lesson
Authors: Kremer Matthias , Bee Ulrich 
Published: November 2019

AbstractWährend das wissenschaftliche Periodensystem der Elemente eine Tabelle der Atomarten darstellt, gibt es für den Chemieunterricht auch didaktisch aufbereitete Periodensysteme, die zusätzlich Informationen über die Verknüpfung von Atomen bzw. Ionen zu Molekülen oder Gittern enthalten. Sie ermöglichen die Thematisierung der chemischen Bindung in systemischer Weise von Anfang an. Damit der Einsatz der beiden vorgeschlagenen Periodensysteme ohne gedankliche Brüche geschehen kann, enthält der Artikel eine Übersicht über alle unterrichtsrelevanten Begriffe und Definitionen der Basiskonzepte Stoff – Teilchen und Struktur – Eigenschaften strukturiert nach den drei Erklärungsebenen und mit zunehmender Eindringtiefe. Daneben wird ein Vorschlag zur Terminologie bei Grundbegriffen wie Stoff, Element, Verbindung unterbreitet, der das Begriffssystem transparenter machen soll.
Genetic association between plasminogen activator inhibitor‐1 rs1799889 polymorphism and venous thromboembolism: Evidence from a comprehensive meta‐analysis
Authors: Huang Guangbin , Wang Pan , Li Tao , Deng Xuejun 
Published: November 2019

AbstractBackgroundAssociation between plasminogen activator inhibitor‐1 (PAI‐1) rs1799889 polymorphism and venous thromboembolism (VTE) were explored by many previous studies, yet the findings of these studies were conflicting.HypothesisPAI‐1 rs1799889 polymorphism may serve as a genetic marker of VTE. We aimed to better clarify the relationship between PAI‐1 rs1799889 polymorphism and VTE in a larger combined population by performing a meta‐analysis.MethodsLiteratures were searched in Pubmed, Embase, Web of Science, and China National Knowledge Infrastructure (CNKI). We used Review Manager to combine the results of individual studies.ResultsForty‐eight studies involving 14 806 participants were eligible for inclusion. Combined results revealed that PAI‐1 rs1799889 polymorphism was significantly associated with VTE in Caucasians (dominant comparison: odds ratio [OR] 1.20, 95% confidence interval [CI] 1.09‐1.32; recessive comparison: OR 0.84, 95% CI 0.76‐0.94; allele comparison: OR 1.08, 95% CI 1.02‐1.15) and East Asians (dominant comparison: OR 1.60, 95% CI 1.17‐2.19; allele comparison: OR 1.53, 95% CI 1.21‐1.93). Further analyses obtained similar significant associations in these with deep vein thrombosis (DVT) and these with Factor V Leiden mutation.ConclusionsOur findings supported that PAI‐1 rs1799889 polymorphism may serve as one of the predisposing factors of VTE in both Caucasians and East Asians, especially in these with DVT and these with Factor V Leiden mutation.
dTACC restricts bouton addition and regulates microtubule organization at the Drosophila neuromuscular junction
Authors: Chou Vivian T. , Johnson Seth , Long Jennifer , Vounatsos Maxime , Van Vactor David 
Published: November 2019

AbstractRegulation of the synaptic cytoskeleton is essential to proper neuronal development and wiring. Perturbations in neuronal microtubules (MTs) are associated with numerous pathologies, yet it remains unclear how changes in MTs may be coupled to synapse morphogenesis. Studies have identified many MT regulators that promote synapse growth. However, less is known about the factors that restrict growth, despite the potential links of synaptic overgrowth to severe neurological conditions. Here, we report that dTACC, which is implicated in MT assembly and stability, prevents synapse overgrowth at the Drosophila neuromuscular junction by restricting addition of new boutons throughout larval development. dTACC localizes to the axonal MT lattice and is required to maintain tubulin levels and the integrity of higher‐order MT structures in motor axon terminals. While previous reports have demonstrated the roles of MT‐stabilizing proteins in promoting synapse growth, our findings suggest that in certain contexts, MT stabilization may correlate with restricted growth.
Synthesis and Anticancer Activity of Tertiary Amides of Salinomycin and Their C20‐oxo Analogues
Authors: Czerwonka Dominika , Urbaniak Alicja , Sobczak Szymon , Piña‐Oviedo Sergio , Chambers Timothy C. , Antoszczak Michał , Huczyński Adam 
Published: November 2019

AbstractThe polyether ionophore salinomycin (SAL) has captured much interest because of its potent activity against cancer cells and cancer stem cells. Our previous studies have indicated that C1/C20 double‐modification of SAL is a useful strategy to generate diverse agents with promising biological activity profiles. Thus, herein we describe the synthesis of a new class of SAL analogues that combine key modifications at the C1 and C20 positions. The activity of the obtained SAL derivatives was evaluated using primary acute lymphoblastic leukemia, human breast adenocarcinoma and normal mammary epithelial cells. One single‐ [N,N‐dipropyl amide of salinomycin (5 a)] and two novel double‐modified analogues [N,N‐dipropyl amide of C20‐oxosalinomycin (5 b) and piperazine amide of C20‐oxosalinomycin (13 b)] were found to be more potent toward the MDA‐MB‐231 cell line than SAL or its C20‐oxo analogue 2. When select analogues were tested against the NCI‐60 human tumor cell line panel, 4 a [N,N‐diethyl amide of salinomycin] showed particular activity toward the ovarian cancer cell line SK‐OV‐3. Additionally, both SAL and 2 were found to be potent ex vivo against human ER/PR+, Her2− invasive mammary carcinoma, with 2 showing minimal toxicity toward normal epithelial cells. The present findings highlight the therapeutic potential of SAL derivatives for select targeting of different cancer types.
Direct Synthesis of Microporous Bicarbazole‐Based Covalent Triazine Frameworks for High‐Performance Energy Storage and Carbon Dioxide Uptake
Authors: Mohamed Mohamed Gamal , EL‐Mahdy Ahmed F. M. , Ahmed Mahmoud M. M. , Kuo Shiao‐Wei 
Published: November 2019

AbstractIn this study a series of bicarbazole‐based covalent triazine frameworks (Car‐CTFs) were synthesized under ionothermal conditions from [9,9'‐bicarbazole]‐3,3',6,6'‐tetracarbonitrile (Car‐4CN) in the presence of molten zinc chloride. Thermogravimetric and Brunauer−Emmett−Teller analyses revealed that these Car‐CTFs possessed excellent thermal stabilities and high specific surface areas (ca. 1400 m2/g). The electrochemical performances of this Car‐CTF series, investigated by using cyclic voltammetry, showed a highest capacitance of (545 F/g at 5 mV/s), which also exhibited excellent columbic efficiencies of 96.1 % after 8000 cycles at 100 μA/0.5 cm2. The other Car‐CTF samples displayed similar efficiencies. Furthermore, based on CO2 uptake measurements, one of the series showed the highest CO2 uptake capacities: 3.91 and 7.60 mmol/g at 298 and 273 K, respectively. These results suggest a simple method for the preparation of CTF materials that provide excellent electrochemical and CO2 uptake performance.
Evaluating the boundaries of marine biogeographic regions of the Southwestern Atlantic using halacarid mites (Halacaridae), meiobenthic organisms with a low dispersal potential
Authors: Pepato Almir R. , Vidigal Teofânia H. D. A. , Klimov Pavel B. 
Published: November 2019

AbstractAimWe evaluated traditional biogeographic boundaries of coastal marine regions in Southwestern Atlantic using DNA sequence data from common, rocky‐shore inhabiting, marine mites of the genera Agauopsis and Rhombognathus, family Halacaridae.MethodsWe investigated geographic population genetic structure using CO1 gene sequences, estimated divergence times using a multigene dataset and absolute time‐calibrated molecular clock analyses, and performed environmental niche modeling (ENM) of common marine mite species.ResultsAgauopsis legionium has a shallow history (2.01 Ma) with four geographically differentiated groups. Two of them corresponded to the traditional Amazonian and Northeastern ecoregions, but the boundary between the two other groups was inferred at the Abrolhos Plateau, not Cabo Frio. Rhombognathus levigatoides s. lat. was represented by two cryptic species that diverged 7.22 (multilocus data) or 10.01 Ma (CO1‐only analyses), with their boundary, again at the Abrolhos Plateau. ENM showed that A. legionium has suitable habitats scattered along the coast, while the two R. levigatoides cryptic species differ considerably in their niches, especially in parameters related to upwelling. This indicates that genetic isolation associated with the Abrolhos Plateau occurred in both lineages, but for the R. levigatoides species complex, ecological niche specialization was also an important factor.Main conclusionsOur study suggests that the major biogeographic boundary in the Southwestern Atlantic lies not at Cabo Frio but at the Abrolhos Plateau. There two biogeographically relevant factors meet (a) changes in current directions (which limit dispersal) and (b) abrupt changes in environmental parameters associated with the South Atlantic Central Waters (SACW) upwelling (offering distinct ecological niches). We suggest that our result represents a general biogeographic pattern because a barrier at the Abrolhos Plateau was found previously for the fish genus Macrodon (phylogeographic data), prosobranch mollusks, ascidians, and reef fishes (community‐level data).
Physical State of β‐Carotene at High Concentrations in a Solid Triglyceride Matrix
Authors: Schjoerring‐Thyssen Jakob , Olsen Karsten , Koehler Klaus , Jouenne Eric , Larsen Flemming Hofmann , Andersen Mogens L. 
Published: November 2019

AbstractThe highly hydrophobic β‐carotene is often distributed or dissolved in triglycerides to enhance either nutritional or coloring effects. This study aims at elucidating the physical state of β‐carotene that at high concentrations are mixed into a solid high‐melting tri‐glyceride matrix by dissolution at high temperatures (165 °C) in the melted triglyceride. Extensive isomerization of β‐carotene is observed by HPLC after melting crystalline all‐trans β‐carotene and in the solid mixtures of β‐carotene and fully hydrogenated sunflower oil. Crystalline triglyceride is found in the mixed samples by XRPD analysis whereas no signs of crystalline lattice structures of β‐carotene are detected. DSC thermograms show only the melting and recrystallization events of triglycerides, which are affected by the presence of β‐carotene. Severe line broadening is observed in the 13C CP/MAS NMR spectra of the β‐carotene‐triglyceride mixtures when compared to crystalline β‐carotene, demonstrating the lack of long‐range order of the carotene. Altogether, the results demonstrate that β‐carotene is present as an amorphous mixture of trans‐ and cis‐isomers dispersed into a structure of crystalline triglyceride in the solid carotene‐triglyceride mixtures.Practical applications: The amorphous structure of trans‐ and cis‐isomers in solid formulations of β‐carotene‐triglyceride mixtures will strongly affect their functional properties related to nutrition and color as food ingredients.