bluuebunny/crossref_metadata_2025_split huggingface dataset:
Surface modification of MWCNT and its influence on properties of paraffin/MWCNT nanocomposites as phase change material
Authors: Avid Arezoo , Jafari Seyed Hassan , Khonakdar Hossein Ali , Ghaffari Mehdi , Krause Beate , Pötschke Petra 
Published: August 2019

ABSTRACTMultiwalled carbon nanotubes (MWCNTs) were modified by an organo‐silane in order to improve their dispersion state and stability in paraffin wax. A family of paraffin‐based phase change material (PCM) composites filled with MWCNTs was prepared with different loadings (0, 0.1, 0.5, and 1 wt%) of pristine MWCNTs and organo‐silane modified MWCNTs (Si‐MWCNT). Structural analyses were performed by means of Fourier transform infrared (FTIR), scanning electron microscopy (SEM), and rheological studies using temperature sweeps. Moreover, phase change transition temperatures and heat of fusion as well as thermal and electrical conductivities of the developed PCM nanocomposites were determined. The SEM micrographs and FTIR absorption bands appearing at approximately 1038 and 1112 cm−1 confirmed the silane modification. Differential scanning calorimetery (DSC) results indicate that the presence of Si‐MWCNTs leads to slightly favorable enhancement in the energy storage capacity at the maximum loading. It was also shown that the thermal conductivity of the PCM nanocomposites, in both solid and liquid phases, increased with increasing the MWCNT content independent of the kind of MWCNTs by up to about 30% at the maximum loading of MWCNTs. In addition, the modification of MWCNTs made the samples completely electrically nonconductive, and the electrical surface resistivity of the PCMs containing pristine MWCNTs decreased with increasing MWCNTs loading. Furthermore, the rheological assessment under consecutive cyclic phase change demonstrated that the samples containing modified MWCNTs are more stable compared to the PCM containing pristine MWCNTs. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48428.
Developing conductive immiscible polystyrene/polypropylene blends with a percolated conducting polyaniline/polyamide filler by tuning its specific interactions with the styrene‐based triblock compatibilizer grafted with maleic anhydride
Authors: Bharati Avanish , Hejmady Prakhyat , Van der Donck Tom , Seo Jin Won , Cardinaels Ruth , Moldenaers Paula 
Published: August 2019

ABSTRACTAn approach to induce conductivity in immiscible polystyrene/polypropylene (PS/PP) blends is described using a percolated conducting polyaniline/polyamide (PANI/PA) filler combined with a polystyrene‐block‐poly(ethylene‐ran‐butylene)‐block‐polystyrene‐graft‐maleic anhydride compatibilizer. The approach is based on the ability of the compatibilizer to concomitantly stabilize the cocontinuous morphology and to improve the state of dispersion of the PANI/PA filler. Selective localization of PANI/PA in the PS phase with improved filler dispersion is achieved with the optimal master batch (MB) preparation technique followed by its optimized sequence addition to the blend components. This results in an increase in the dc conductivity by six decades as compared with that of the neat compatibilized blend at an effective 4.8‐wt % PANI concentration. An investigation of the effect of functionality and concentration of the filler and the compatibilizer on the filler connectivity in the blend is performed. The prevailing specific interactions are analyzed by Fourier transform infrared spectroscopy and thermogravimetric analysis of the MBs. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48433.
Effect of ionic liquid on the structure and desalination performance of PVDF‐PTFE electrospun membrane
Authors: Li Jun , Ren Long‐Fei , Shao Jiahui , Adeel Mister , Tu Yonghui , Ma Zhongbao , He Yiliang 
Published: August 2019

ABSTRACTThe relatively large pore size of electrospun membranes might limit their application for direct contact membrane distillation (DCMD). Incorporation of ionic liquid is a potential approach to decrease the pore size of electrospun membranes, which was attributed to the increased conductivity of electrospinning solution. In this study, a novel nanofibrous membrane based on the blends of poly(vinylidene fluoride) (PVDF), polytetrafluoroethylene (PTFE) and ionic liquid (BMIMPF6) was fabricated and applied for the DCMD. The effects of the BMIMPF6 on the morphology, pore size and DCMD performance of the PVDF‐PTFE nanofibrous membrane were investigated. Compared with neat (PVDF‐PTFE) membranes (average pore size: 0.93 μm), the incorporation of BMIMPF6 resulted in a smaller mean pore diameter (0.58 μm). The liquid entry pressure value of the modified composite membrane also increased from 62.75 kPa (neat) to 83 kPa, due to the decreased pore size. The composite membrane exhibited a longer lifespan (about 26 h) than neat membrane during long‐term DCMD process, which makes this composite membrane a promising candidate for DCMD application. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48467.
Structural diversity of adipokinetic hormones in the hyperdiverse coleopteran Cucujiformia
Authors: Gäde Gerd , Šimek Petr , Marco Heather G. 
Published: August 2019

AbstractSeventeen species of the coleopteran series Cucujiformia are investigated for the presence and sequence of putative adipokinetic hormones (AKHs). Cucujiformia includes species from the major superfamilies, that is, Chrysomeloidea, Curculionoidea, Cucujoidea, and Tenebrionoidea. The clade Phytophaga in which the Chrysomeloidea and Curculionoidea reside, harbor very detrimental species for agriculture and forestry. Thus, this study aims not only to demonstrate the structural biodiversity of AKHs in these beetle species and possible evolutionary trends but also to determine whether the AKHs from harmful pest species can be used as lead substances for a future putative insecticide that is harmless to beneficial insects. Sequence analysis of AKHs is achieved by liquid chromatography coupled to mass spectrometry. Most of the investigated species contain AKH octapeptides in their corpora cardiaca, although previously published work also found a few decapeptides, which we comment on. The signature and sole AKH in cerambycidae Chrysomeloidea and Curculionoidea is Peram‐CAH‐I (pEVNFSPNW amide), which is also found in the majority of chrysomelidae Chrysomeloidea and in the one investigated species of Cucujoidea albeit in a few cases associated with a second AKH which can be either Peram‐CAH‐II (pELTFTPNW amide), Emppe‐AKH (pEVNFTPNW amide), or Micvi‐CC (pEINFTPNW amide). The most often encountered AKH in Tenebrionoidea, family Meloidae as well as family Tenebrionidae, is Tenmo‐HrTH (pELNFSPNW amide) followed by Pyrap‐AKH (pELNFTPNW amide) and a Tenmo‐HrTH extended decapeptide (in Meloidae). Finally, we examine AKH sequences from 43 species of cucujiform beetles, including the superfamily Coccinelloidea for a possible lead compound for producing a cucujiform‐specific pesticide.
Stability and change in social interaction style of children with autism spectrum disorder: A 4‐year follow‐up study
Authors: Scheeren Anke M. , Koot Hans M. , Begeer Sander 
Published: August 2019

Children with autism spectrum disorder (ASD) show atypical social behavior but vary in their social interaction style (SIS), ranging from social aloofness to awkward social approaches. In a 4‐year follow‐up study, we examined longitudinal stability and change of SIS in children and adolescents with ASD and a normal intellectual ability (n = 55; mean age Time 1: 13 years; mean age Time 2: 17 years). Children's SIS was assessed with a parent questionnaire, the Wing Subtypes Questionnaire. As expected, most participants (69%) showed SIS stability across the 4‐year interval. Some participants (18%) shifted to a more typical or more active (but odd) SIS, while others (13%) shifted to a less typical or less active (but odd) SIS. A decrease in ASD symptoms predicted a shift toward a more typical or active SIS, but children's age and receptive verbal ability did not. SISs may be a meaningful way to create ASD subgroups and thus offer a promising research venue to further disentangle the heterogeneous autism spectrum. Autism Res 2020, 13: 74–81. © 2019 The Authors. Autism Research published by International Society for Autism Research published by Wiley Periodicals, Inc.Lay SummaryPeople with autism spectrum disorder (ASD) demonstrate different social interaction styles (SIS), ranging from social aloofness to awkward social approaches. We examined if and how SIS changes across a 4‐year period in 55 children and adolescents with ASD (mean age Time 1 = 13 years; mean age Time 2 = 17 years). Most children (69%) showed the same SIS at both time points, indicating that SIS might be a relatively stable trait across adolescence.
Molecular Structure of Binary Chromium(III)–DNA Adducts
Authors: Brown Silas , Lockart Molly M. , Thomas C. Sumner , Bowman Michael K. , Woski Stephen A. , Vincent John B. 
Published: August 2019

AbstractChromium(VI) is a carcinogen and mutagen, and its mechanisms of action are proposed to involve binding of its reduction product, chromium(III), to DNA. The manner in which chromium(III) binds DNA has not been established, particularly at a molecular level. Analysis of oligonucleotide duplex DNAs by NMR, EPR, and IR spectroscopies in the presence of chromium(III) allows the elucidation of the Cr binding site. The metal centers were found to interact exclusively with guanine N7 positions. No evidence of chromium interactions with other bases or backbone phosphates nor of Cr forming intra‐strand crosslinks between neighboring guanine residues was observed.
Risk factors for infective endocarditis following transcatheter pulmonary valve replacement in patients with congenital heart disease
Authors: Sadeghi Soraya , Wadia Subeer , Lluri Gentian , Tarabay Jana , Fernando Anisha , Salem Morris , Sinha Sanjay , Levi Daniel S. , Aboulhosn Jamil 
Published: August 2019

AbstractObjectivesWe sought to delineate the risk factors for infective endocarditis (IE) in patients undergoing transcatheter pulmonary valve replacement (TCPVR).BackgroundDespite the therapeutic benefits of TCPVR for treatment of dysfunctional right ventricular outflow tracts, IE is a major complication of the approach. Specific hemodynamic gradients and patient immune status as predisposing factors for IE are largely unexplored.MethodsWe performed a retrospective review of patients who had undergone TCPVR at UCLA between October 2010 and October 2017. Cases of IE were diagnosed based on the modified Duke criteria.ResultsTwo hundred and thirty‐five cases of TCPVR were performed with a mean follow‐up of 2.6 years (range 0.0–8.0 years). Sixteen distinct IE events developed in 13 patients (Melody™ n = 12, SAPIEN n = 1), with a median time from implant to IE of 3.3 years (range 2.0–7.2 years). Univariate Cox regression showed that immunocompromised status was significantly associated with the development of IE hazard ratios (HR 5.43 [1.80–16.4], p = .003). Kaplan–Meier curves show that the 5‐year freedom from IE among immunocompetent patients was 87% (95% CI 78–96%) versus 64% (95% CI 39–89%) among immunocompromised patients (log‐rank p = .02). Postimplant right ventricular systolic pressure was higher among immunocompromised patients (p = .03). The risk of IE post‐TCPVR in immunocompromised patients with residual pulmonary stenosis was 43%.ConclusionsAmong the risk factors examined in this study, immunocompromised status was the most significant predictor of IE development post‐TCPVR. Patients with the lowest risk of IE are those with competent immune systems, without a history of IE, and with minimal residual pulmonary valve gradients post‐TCPVR.
Initial experience with vascular plug devices for mechanical thrombectomy in symptomatic neonates and infants
Authors: McGovern Eimear , Qureshi Athar M. , Goldstein Bryan H. 
Published: August 2019

AbstractObjectivesTo describe a novel technique for mechanical thrombectomy (MT) in young children.BackgroundAcute thrombosis in children may be a cause of significant morbidity or mortality. MT options in children are limited due to patient and vessel size, prompting consideration of innovative approaches.MethodsTwo‐center review of children with symptomatic non‐cerebral thrombotic vessel occlusion. A novel approach to MT was performed using a deployed but unreleased amplatzer vascular plug (AVP) to “scrape” the target vessel in retrograde fashion, thereby harvesting the thrombus via the access sheath.ResultsAVP‐MT was performed in four patients at a median age of 2 months (range: 1 day‐11 months) and median weight of 5.6 kg (1.8–10.9). In two cases, AVP‐MT was performed in isolation in neonates on cervical extracorporeal membrane oxygenation (ECMO) support with cannula‐associated obstructive aortic and brachiocephalic thrombus. AVP‐MT was also performed as adjunctive therapy in a patient with single ventricle physiology and pulmonary artery thrombosis and in an infant with mitral valve endocarditis and femoral arterial thromboembolism. In all cases, AVP‐MT was used to successfully remove thrombus from the target vessel and restore arterial flow, without procedural complications. Recurrent thrombosis occurred in both neonates, due to persistence of the ECMO cannula, with subsequent mortality. The other children were free of recurrent thrombus at 2 and 34 months.ConclusionsAcute relief of symptomatic thrombosis may be achieved using AVP‐MT in small children, although thrombosis frequently recurs, and clinical prognosis may remain poor. This strategy should be considered when alternative MT treatment options are not applicable.
N‐Heterocyclic Olefins as Electron Donors in Combination with Triarylborane Acceptors: Synthesis, Optical and Electronic Properties of D–π–A Compounds
Authors: He Jiang , Rauch Florian , Friedrich Alexandra , Sieh Daniel , Ribbeck Tatjana , Krummenacher Ivo , Braunschweig Holger , Finze Maik , Marder Todd B. 
Published: August 2019

AbstractN‐heterocyclic olefins (NHOs), relatives of N‐heterocyclic carbenes (NHCs), exhibit high nucleophilicity and soft Lewis basic character. To investigate their π‐electron donating ability, NHOs were attached to triarylborane π‐acceptors (A) giving donor (D)–π–A compounds 1–3. In addition, an enamine π‐donor analogue (4) was synthesized for comparison. UV–visible absorption studies show a larger red shift for the NHO‐containing boranes than for the enamine analogue, a relative of cyclic (alkyl)(amino) carbenes (CAACs). Solvent‐dependent emission studies indicate that 1–4 have moderate intramolecular charge‐transfer (ICT) behavior. Electrochemical investigations reveal that the NHO‐containing boranes have extremely low reversible oxidation potentials (e.g., for 3,
=−0.40 V vs. ferrocene/ferrocenium, Fc/Fc+, in THF). Time‐dependent (TD) DFT calculations show that the HOMOs of 1–3 are much more destabilized than that of the enamine‐containing 4, which confirms the stronger donating ability of NHOs.
Reversible Wide‐Range Tuneable Luminescence of a Dual‐Stimuli‐ Responsive Silver Cluster‐Assembled Material
Authors: Ma Xiao‐Hong , Wang Jia‐Yin , Guo Jun‐Jie , Wang Zhao‐Yang , Zang Shuang‐Quan 
Published: August 2019

Summary of main observation and conclusionSilver cluster‐assembled materials (SCAMs) are emerging multi‐functional materials and have attracted great attention recently. In this work, we have prepared a new SCAM of {[Ag18(StBu)10(CF3COO)2(PhPO3)(PhPO3H)4(bpy‐NH2)2]∙(PhPO3H2)}n (denoted as Ag18bpy‐NH2), by a facile one‐pot method. Ag18bpy‐NH2 adopts a chain‐like structure made of Ag18 clusters bridged by bipyridyl linkers. Ag18bpy‐NH2 exhibits reversible luminescent mechanochromism upon mechanical stimulation and solvent treatment. Moreover, it also displays luminescent thermochromism with a linear relationship of the temperature to the intensity ratio of the dual emissions over a wide temperature range of 83 to 303 K. This work might provide new insights into the assembly of multifunctional stimuli‐responsive SCAMs.
Combining Zinc Phthalocyanines, Oligo(p‐Phenylenevinylenes), and Fullerenes to Impact Reorganization Energies and Attenuation Factors
Authors: Krug Marcel , Stangel Christina , Zieleniewska Anna , Clark Timothy , Torres Tomás , Coutsolelos Athanassios G. , Guldi Dirk M. 
Published: August 2019

AbstractA study on electron transfer in three electron donor‐acceptor complexes is reported. These architectures consist of a zinc phthalocyanine (ZnPc) as the excited‐state electron donor and a fullerene (C60) as the ground‐state electron acceptor. These complexes are brought together by axial coordination at ZnPc. The key variable in our design is the length of the molecular spacer, namely, oligo‐p‐phenylenevinylenes. The lack of appreciable ground‐state interactions is in accordance with strong excited‐state interactions, as inferred from the quenching of ZnPc centered fluorescence and the presence of a short‐lived fluorescence component. Full‐fledged femtosecond and nanosecond transient absorption spectroscopy assays corroborated that the ZnPc ⋅ +‐C60 ⋅ − charge‐separated state formation comes at the expense of excited‐state interactions following ZnPc photoexcitation. At a first glance, the ZnPc ⋅ +‐C60 ⋅ − charge‐separated state lifetime increased from 0.4 to 86.6 ns as the electron donor‐acceptor separation increased from 8.8 to 29.1 Å. A closer look at the kinetics revealed that the changes in charge‐separated state lifetime are tied to a decrease in the electronic coupling element from 132 to 1.2 cm−1, an increase in the reorganization energy of charge transfer from 0.43 to 0.63 eV, and a large attenuation factor of 0.27 Å−1.
Analysis of Drosophila nervous system development following an early, brief exposure to ethanol
Authors: Scepanovic Gordana , Stewart Bryan A. 
Published: August 2019

AbstractThe effects of ethanol on neural function and development have been studied extensively, motivated in part by the addictive properties of alcohol and the neurodevelopmental deficits that arise in children with fetal alcohol spectrum disorder (FASD). Absent from this research area is a genetically tractable system to study the effects of early ethanol exposure on later neurodevelopmental and behavioral phenotypes. Here, we used embryos of the fruit fly, Drosophila melanogaster, as a model system to investigate the neuronal defects that arise after an early exposure to ethanol. We found several disruptions of neural development and morphology following a brief ethanol exposure during embryogenesis and subsequent changes in larval behavior. Altogether, this study establishes a new system to examine the effects of alcohol exposure in embryos and the potential to conduct large‐scale genetics screens to uncover novel factors that sensitize or protect neurons to the effects of alcohol.
Identification of specific markers for amphetamines synthesized from glycidic acid pre‐precursors and retrospective search in German profiling database
Authors: Hauser Frank M. , Pütz Michael , Rößler Thorsten , Hulshof Janneke W. 
Published: August 2019

AbstractThe pre‐precursor market and the clandestine production of amphetamine‐type stimulants (ATS) has become more diverse in recent years. Besides α‐phenylacetoacetonitrile (APAAN) and α‐phenylacetoacetamide (APAA), glycidic acid derivatives and methyl α‐phenylacetoacetate (MAPA) are gaining importance. This conclusion is based on seizure data of police and customs. However, analytical data are needed to confirm and quantify the actual prevalence of new pre‐precursors by elucidating the percentage of seized ATS that have been produced from them. A recent study showed that APAAN use is currently declining, which supports the view that new pre‐precursors are being used. In this study, several conversion procedures using different batches of glycidic acid derivatives and a complete Leuckart reaction to produce amphetamine were carried out. The resulting organic phases were analyzed using gas chromatography − mass spectrometry to identify possible marker compounds. Three marker compounds were discovered and characterized using mass spectra and nuclear magnetic resonance spectroscopy. They were identified as phenyl‐1‐propanone, N‐(1‐phenylpropyl)formamide and 1‐phenylpropan‐1‐amine. Their prevalence was investigated by searching the markers in an amphetamine impurity profiling database to determine to what extent they occurred in amphetamine samples from recent years. Data from the central German amphetamine profiling database of more than 250 cases were used for this purpose. The yearly occurrence of the three glycidate marker compounds was determined going back as far as 2009, revealing an increasing trend from 2016 on. This article presents experimental proof that APAAN is currently being replaced by other pre‐precursors, such as glycidic acid derivatives.
Joint estimation of growth and survival from mark–recapture data to improve estimates of senescence in wild populations
Authors: Reinke Beth A. , Hoekstra Luke , Bronikowski Anne M. , Janzen Fredric J. , Miller David 
Published: August 2019

AbstractUnderstanding age‐dependent patterns of survival is fundamental to predicting population dynamics, understanding selective pressures, and estimating rates of senescence. However, quantifying age‐specific survival in wild populations poses significant logistical and statistical challenges. Recent work has helped to alleviate these constraints by demonstrating that age‐specific survival can be estimated using mark–recapture data even when age is unknown for all or some individuals. However, previous approaches do not incorporate auxiliary information that can improve age estimates of individuals. We introduce a survival estimator that combines a von Bertalanffy growth model, age‐specific hazard functions, and a Cormack‐Jolly‐Seber mark–recapture model into a single hierarchical framework. This approach allows us to obtain information about age and its uncertainty based on size and growth for individuals of unknown age when estimating age‐specific survival. Using both simulated and real‐world data for two painted turtle (Chrysemys picta) populations, we demonstrate that this additional information substantially reduces the bias of age‐specific hazard rates, which allows for the testing of hypotheses related to aging. Estimating patterns of senescence is just one practical application of jointly estimating survival and growth; other applications include obtaining better estimates of the timing of recruitment and improved understanding of life‐history trade‐offs between growth and survival.