bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Phosphoramidite Analogue of Cyclotriphosphate Enables Iterative Polyphosphorylations
Authors: Singh Jyoti , Steck Nicole , De Debaditya , Hofer Alexandre , Ripp Alexander , Captain Ilya , Keller Manfred , Wender Paul A. , Bhandari Rashna , Jessen Henning J. 
Published: January 2019

AbstractAn iterative polyphosphorylation approach is described, which is based on a phosphoramidite (P‐amidite) derived reagent (c‐PyPA) obtained from the cyclization of pyrophosphate with a reactive diisopropylaminodichlorophosphine. This type of reagent is unprecedented as it represents a reactive P‐amidite without protecting groups. The reagent proved to be stable in solution over several weeks. Its utility is described in the context of iterative monodirectional and bidirectional polyphosphorylations. The ensuing functionalized cyclotriphosphate can be opened with a variety of nucleophiles providing ready access to diverse functionalized polyphosphate chains of defined length with several tags, including both P‐N and P‐O labels. Their interaction with exo‐ and endopolyphosphatases is described.
A Photoresponsive Stiff‐Stilbene Ligand Fuels the Reversible Unfolding of G‐Quadruplex DNA
Authors: O'Hagan Michael P. , Haldar Susanta , Duchi Marta , Oliver Thomas A. A. , Mulholland Adrian J. , Morales Juan C. , Galan M. Carmen 
Published: January 2019

AbstractThe polymorphic nature of G‐quadruplex (G4) DNA structures points to a range of potential applications in nanodevices and an opportunity to control G4 in biological settings. Light is an attractive means for the regulation of oligonucleotide structure as it can be delivered with high spatiotemporal precision. However, surprisingly little attention has been devoted towards the development of ligands for G4 that allow photoregulation of G4 folding. We report a novel G4‐binding chemotype derived from stiff‐stilbene. Surprisingly however, whilst the ligand induces high stabilization in the potassium form of human telomeric DNA, it causes the unfolding of the same G4 sequence in sodium buffer. This effect can be reversed on demand by irradiation with 400 nm light through deactivation of the ligand by photo‐oxidation. By fuelling the system with the photolabile ligand, the conformation of G4 DNA was switched five times.
Robust, recoverable poly(N,N‐dimethylacrylamide)‐based hydrogels crosslinked by vinylated chitosan with recyclable adsorbability for acid red
Authors: Wang Xiaoning , Xing Yacheng , Zhao Xihui , Ji Quan , Xia Yanzhi , Ma Xiaomei 
Published: January 2019

ABSTRACTTo seek adsorptive hydrogels with high stability, poly(N,N‐dimethylacrylamide) (PDMAM)‐based hydrogels were fabricated employing vinylated chitosan as a macro‐crosslinker. The prepared hydrogels achieves a maximum compressive stress above 11 MPa (98% strain), a maximum tensile strength, and fracture elongation of 0.037 MPa and 929%. The recovery ratios after three consecutive compressions (90% strain) and 1 h's resting (600% stretch) exceed 94% and 85%, respectively. The optimal adsorption effect (>90% removal efficiency) is achieved at pH 3 and 318 K in 2.5 h using hydrogels crosslinked by 9.77 wt % chitosan. The kinetic study indicates that the experimental data fit to the pseudo‐second‐order kinetic model better. The adsorption isotherm fits to the Freundlich model, indicating nonhomogeneous adsorption of the dyes on the hydrogels. Most adsorbed dyes are desorbed in 2 h at pH 10 and 318 K, both adsorption/desorption efficiencies exceed 90% after five adsorption–desorption cycles, confirming reusability of the hydrogels. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47473.
Durability of the flame retardance of ethylene‐vinyl acetate copolymer cables: Comparing different flame retardants exposed to different weathering conditions
Authors: Tan Yi , Wachtendorf Volker , Klack Patrick , Kukofka Tobias , Ruder Jörg , Schartel Bernhard 
Published: January 2019

ABSTRACTScientific publications addressing the durability of the flame retardance of cables during their long‐term application are rare and our understanding lacks. Three commercial flame retardants, aluminum hydroxide, aluminum diethyl phosphinate (AlPi‐Et), and intumescent flame retardant based on ammonium polyphosphate, applied in ethylene‐vinyl acetate copolymer (EVA) model cables, are investigated. Different artificial aging scenarios were applied: accelerated weathering (UV‐irradiation/temperature/rain phases), humidity exposure (elevated temperature/humidity), and salt spray exposure. The deterioration of cables' surface and flame retardancy were monitored through imaging, color measurements, attenuated total reflectance Fourier transform infrared spectroscopy, and cone calorimeter investigations. Significant degradation of the materials' surface occurred. The flame retardant EVA cables are most sensitive to humidity exposure; the cable with AlPi‐Et is the most sensitive to the artificial aging scenarios. Nevertheless, substantial flame retardance persisted after being subjected for 2000 h, which indicates that the equivalent influence of natural exposure is limited for several years, but less so for long‐term use. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 47548.
Reactive particles from in situ silane‐polycondensation‐induced self‐assembly of poly(styrene‐alt‐maleic anhydride) as toughener for epoxy resins
Authors: Wei Wei , Cui Yuqing , Li Xiaojie , Gu Yao , Fei Xiaoma , Luo Jing , Liu Xiaoya 
Published: January 2019

ABSTRACTThe partial aminolysis of poly(styrene‐alt‐maleic anhydride) (SMA) with 3‐aminopropyltriethoxysilane (APTES) was carried out followed by in situ hydrolytic condensation of the silane, for inducing the self‐assembly of SMA to prepare an organic–inorganic hybrid colloidal particle (SMA‐APTES). The obtained SMA‐APTES particles were then employed as a toughener for modifying diglycidylether of bisphenol A/anhydride thermoset. When the additive amount of the modifier was 5 wt %, an optimal overall performance was achieved. Compared to neat epoxy thermoset, the tensile strength, elongation‐ at‐break, impact strength, and fracture toughness were increased by 67.6, 159, 170.5, and 230.9%, respectively. Although SMA‐APTES particles inherently had low glass‐transition temperature (Tg) and thermal stability, the Tg and thermal stability of above case were comparable to that of neat epoxy resin. It was contributed by the remarkable increase in the crosslink density offsetting this shortage. Therefore, SMA‐APTES particle was proved to be an effective and promising modifier for epoxy thermoset. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47565.
Minimal overlap between areas of high conservation priority for endangered Galapagos pinnipeds and the conservation zone of the Galapagos Marine Reserve
Authors: Ventura Francesco , Matthiopoulos Jason , Jeglinski Jana W.E. 
Published: January 2019

Abstract

Galapagos sea lions (Zalophus wollebaeki) and fur seals (Arctocephalus galapagoensis) are endangered pinnipeds that live in a highly variable marine environment, influenced by seasonal changes in productivity and by the unpredictable occurrence of El Niño. The Galapagos marine habitat is protected through the Galapagos Marine Reserve (GMR), which has recently undergone a redefinition of its zonation. However, the effectiveness of the GMR in protecting the habitat of Galapagos pinnipeds has never been investigated, and it is unclear how well their habitat use aligns with the newly proposed conservation zone.
A spatial prioritization analysis framework was applied based on the complementary use of density estimation (kernel utilization distributions, KUDs) and habitat modelling (resource selection functions, RSFs). Using tracking data collected over two years and under three environmental scenarios (cold season, warm season, and El Niño) in the western archipelago, hot spots of pinniped habitat usage were identified (through KUDs), and predictions about the location of patches of good habitat were generated (through RSFs). The output of KUDs and RSFs was used for a spatial prioritization analysis to delineate areas of high conservation priority. The overlap between these areas and the GMR zonation was then calculated.
Both species were found to use largely distinct habitat types: sea lions used the waters over the continental shelf, whereas fur seals used the offshore deep waters and showed a more heterogeneous space usage over time. The spatial prioritization analysis identified three key areas of high conservation priority for both species in the Western Galapagos. These areas were all within the boundaries of the GMR but the overlap with the conservation zone was only 8%. Hence, under the current proposition, the largest proportion of key pinniped foraging habitat in the western archipelago will not be protected from licensed activities in the sustainable use zone, particularly fishing and boat traffic.
Faseroptische Sensoren zur kontinuierlichen Dehnungsmessung im Beton
Authors: Speck Kerstin , Vogdt Fritz , Curbach Manfred , Petryna Yuri 
Published: January 2019

AbstractDie Ermittlung lastinduzierter, anisotroper Schädigungen unter verschiedenen mehraxialen Spannungszuständen bedingt die Dehnungsmessung im Inneren kleinformatiger Probekörper. Die Wahl fiel auf quasi‐kontinuierlich messende, faseroptische Sensoren ohne werksseitige Schutzummantelung. Dieser Beitrag erläutert das Messprinzip und zeigt, welche Messkonfigurationen bestehend aus Messsystem, Sensorfaser und Coatingmaterial für diese Aufgabe geeignet sind und mit welchen Hilfskonstruktionen die Positionierung der Messsensoren im Probekörper gelingt, um besonders auch im Bereich kleiner Dehnungen exakte Messwerte zu erhalten, die mindestens die gleiche Genauigkeit wie die etablierten Messsysteme Dehnmessstreifen und Photogrammetrie aufweisen. Dafür werden einaxiale Druck‐ und Zugversuche an Mörtelprismen ausgewertet und ein geeignetes Messkonzept für kommende mehraxiale Versuche entwickelt.
Analysis of cause of death: Competing risks or progressive illness‐death model?
Authors: Lauseker Michael , zu Eulenburg Christine 
Published: January 2019

AbstractThe analysis of cause of death is increasingly becoming a topic in oncology. It is usually distinguished between disease‐related and disease‐unrelated death. A frequently used approach is to define death as disease‐related when a progression to advanced phases has occurred before, otherwise as disease‐unrelated. The data are often analyzed as competing risks, while a progressive illness‐death model might in fact describe the situation more precisely. In this study, we investigated under which circumstances this misspecification leads to biased estimations of the state occupation probabilities. We simulated data according to the progressive illness‐death model in various settings, analyzed them with a competing risks model and with a progressive illness‐death model and compared them to the true state occupation probabilities. Censoring was either added independently of the status or based on the patients' status. The simulations showed that the censoring mechanism was decisive for the bias while neither the progression hazard nor the Markov property was important. Further, we found a slightly increased standard deviation for the competing risk estimator when censoring was independent of the patients' status. For illustration, both methods were applied to two practical examples of chronic myeloid leukemia (CML): one randomized controlled trial and one registry data set. While in the first case both estimators yielded almost identical results, in the latter case, visible differences were found between both methods.
LESM—An object‐oriented MATLAB program for structural analysis of linear element models
Authors: Rangel Rafael Lopez , Martha Luiz Fernando 
Published: January 2019

AbstractThis paper describes the implementation of a MATLAB program based on the Object Oriented Programming paradigm for linear‐elastic analysis of one‐dimensional element models using a conventional displacement‐based procedure. The main objective is the development of an educational tool on matrix structural analysis with a didactic and well‐documented open source code, which allows any user to implement new procedures with relative simplicity. The LESM (Linear Elements Structure Model) program can handle different types of analysis models, such as 2D/3D frames and trusses, and grillages. In addition, both Euler‐Bernoulli and Timoshenko theories for bending behavior of beam elements are considered. The OOP class architecture was devised for generically handling these different types of analyses models and element types. The MATLAB script codes of all classes and methods of LESM, including its documentation, are available in its site (www.tecgraf.puc-rio.br/lesm).
Impact of calcification on percutaneous coronary intervention: MACE‐Trial 1‐year results
Authors: Sharma Samin K. , Bolduan Ryan W. , Patel Manesh R. , Martinsen Brad J. , Azemi Talhat , Giugliano Gregory , Resar Jon R. , Mehran Roxana , Cohen David J. , Popma Jeffrey J. , Waksman Ron 
Published: January 2019

AbstractObjectivesThe Multi‐center Prospective Study to Evaluate Outcomes of Moderate to Severely Calcified Coronary Lesions (MACE—Trial) was designed to provide further insight on the impact of calcification on procedural and long‐term percutaneous coronary intervention outcomes.BackgroundPrior studies evaluating the impact of lesion calcification on percutaneous coronary intervention outcomes are limited by: retrospective nature, pooled data from multiple studies, or lack of specificity around calcification with only operator assessment and without core lab evaluation.MethodsThe MACE‐Trial was a prospective, multicenter, observational clinical study that enrolled 350 subjects at 33 sites from September 2013 to September 2015. Core lab assessed subject stratification by lesion calcification (none/mild [N = 133], moderate [N = 99], and severe [N = 114]). Endpoints were lesion success, procedural success, and 1‐year major adverse cardiac events (MACEs).ResultsPresence of severe calcification had significant impact on lesion success ([83.3%] versus none/mild calcification [94.7%, P = 0.006]) and procedural success ([86.8%] versus moderate [95.0%, P = 0.028], and none/mild [97.7%, P = 0.001]). 1‐year MACE rates were associated with presence of calcification in subjects with none/mild (4.7%), moderate (8.7%), and severe (24.4%) (P < 0.001) calcification; however, no difference was noted between none/mild and moderate (P = 0.237). The risk adjusted multivariable model identified severe calcification and decreasing eGFR as predictors of 30‐day and 1‐year MACE.ConclusionsIn this prospective study, patients with severe calcification had significantly worse outcomes compared to those without; however, unlike previous retrospective studies, moderate calcium resulted in similar outcomes as none/mild calcium.Clinical Trial RegistrationURL: https://clinicaltrials.gov/ct2/show/NCT01930214. Unique Identifier: NCT01930214.
On‐site treatment of oral ulcers caused by cheek biting: A minimally invasive treatment approach in a pediatric patient
Authors: Ngoc Vo Truong Nhu , Hang Luong Minh , Bach Hoang Van , Chu Dinh‐Toi 
Published: January 2019

Key Clinical MessageIn small children, it would be desirable for oral lesions, especially on the symmetrical sides, to be screened carefully, and for treatment to begin with minimal interventions including on‐site medication and remedies to discontinue the bad routine. Minimal invasive approach and differential diagnosis are considered to be the main solutions for oral ulcers in pediatric patients.
Spectroelectrochemical Investigation of Cholesterol Oxidase from Streptomyces lividans at Different pH Values
Authors: Heinelt Manuel , Nöll Tanja , Nöll Gilbert 
Published: January 2019

AbstractCholesterol oxidase from Streptomyces lividans (SlChOx) has been investigated by spectroelectrochemistry in the pH range between pH 5 and pH 9. SlChOx is a monomeric flavoenzyme with a molar mass of about 58 kDa that contains a non‐covalently bound flavin adenine dinucleotide (FAD) cofactor. Spectroelectrochemical measurements were carried out in the presence of different one and two electron redox mediators and methylene blue only, as methylene blue does not contribute significantly to the spectral changes between 350 nm and 500 nm. During the stepwise reduction and reoxidation, the presence of a stable singly reduced flavosemiquinone radical anion was observed. The pH dependent midpoint potentials (Em, pH7≈0 mV) and the redox potentials for the first and second transition Fl(quinone)/Fl(semiquinone rad anion) and Fl(semiquinone rad anion)/Fl(hydroquinone anion) were determined. A pH dependency of about −30 mV and −50 mV per pH unit was determined for the first and second reduction, respectively.
Direct Electron Transfer of Enzymes Facilitated by Cytochromes
Authors: Ma Su , Ludwig Roland 
Published: January 2019

AbstractInvited for this month's cover picture is Su Ma and Roland Ludwig from BOKU—University of Natural Resources and Life Sciences, Vienna (Austria). The cover picture schematically shows electron‐transfer routes of five different types of redox centers found in multi‐cofactor oxidoreductases towards a cytochrome domain, which is capable of direct electron transfer. Read the full text of the Review at 10.1002/celc.201801256.
Smart Nanodrug with Nuclear Localization Sequences in the Presence of MMP‐2 To Overcome Biobarriers and Drug Resistance
Authors: Mo Liuting , Zhao Zilong , Hu Xiaoxiao , Yu Xuan , Peng Yongbo , Liu Hui , Xiong Mengyi , Fu Ting , Jiang Ying , Zhang Xiaobing , Tan Weihong 
Published: January 2019

AbstractA series of physiological barriers have impeded nanoparticle‐based drug formulations (NDFs) from reaching their targeted sites and achieving therapeutic outcomes. In this study, we develop size‐controllable stealth doxorubicin‐loaded nanodrug coated with CD47 peptides (DOX/sNDF‐CD47) based on supramolecular chemistry to overcome multiple biological barriers. The smart DOX/sNDF‐CD47 can efficiently decrease sequestration by macrophages and disassemble into poly(amidoamine) dendrimers with nuclear localization sequences (DOX/PAMAM‐NLS) in the presence of matrix metalloproteinase‐2 (MMP‐2). Such structure transformation endows DOX/sNDF‐CD47 with the ability of deep penetration in multicellular tumor spheroid, lysosomal escape, and nucleus localization, resulting in excellent cytotoxicity and drug resistance combating. In vivo experiments further confirmed that DOX/sNDF‐CD47 has good tumor‐targeting ability and can significantly improve therapeutic efficacy of DOX on xenograft tumor model. The ability to overcome multiple biological barriers makes sNDF‐CD47 a promising NDFs to treat cancer expressing MMP‐2 and combating drug resistance.
Aggregation and Tunable Color Emission Behaviors of l‐Glutamine‐Derived Platinum(II) Bipyridine Complexes by Hydrogen‐Bonding, π–π Stacking and Metal–Metal Interactions
Authors: Ai Yeye , Li Yongguang , Fu Heidi Li‐Ki , Chan Alan Kwun‐Wa , Yam Vivian Wing‐Wah 
Published: January 2019

AbstractAn l‐glutamine‐derived functional group was introduced to the bis(arylalkynyl)platinum(II) bipyridine complexes 1–4. The emission could be switched between the 3MLCT excited state and the triplet excimeric state through solvent or temperature changes, which is attributed to the formation and disruption of hydrogen‐bonding, π–π stacking, and metal–metal interactions. Different architectures with various morphologies, such as honeycomb nanostructures and nanospheres, were formed upon solvent variations, and these changes were accompanied by 1H NMR and distinct emission changes. Additionally, yellow and red emissive metallogels were formed at room temperature due to the different aggregation behaviors introduced by the substituent groups on bipyridine. The thermoresponsive metallogel showed emission behavior with tunable colors by controlling the temperature. The negative Gibbs free‐energy change (ΔG) and the large association constant for excimer formation have suggested that the molecules undergo aggregation through hydrogen‐bonding, π–π, and metal–metal interactions, resulting in triplet excimeric emission.
3H‐Phosphaallenes Revisited: Facile Synthesis by Hydroalumination of Alkynylphosphines and β‐Elimination, Stability and Trapping of Transient Species by Coordination to Transition Metal Atoms
Authors: Klöcker Hans , Tendyck Jonas C. , Keweloh Lukas , Hepp Alexander , Uhl Werner 
Published: January 2019

AbstractA facile method for the efficient synthesis of 3H‐phosphaallenes, R−P=C=C(H)−R′, is presented, which comprises treatment of dialkynylphosphines with dialkylaluminium hydrides (hydroalumination) and elimination of aluminium alkynides from intermediate alkenyl‐alkynylphosphines. The stability of the phosphaallenes depends on steric shielding by the substituents at phosphorus (aryl or CH(SiMe3)2 groups). Only supermesityl compounds are persistent at room temperature in solution. This simple method starting with easily accessible dialkynylphosphines and commercially available aluminium hydrides (HAlEt2, HAliBu2) allows the generation of transient species, which were trapped by coordination to transition metals. The η1‐coordination via a P−W bond was observed for tungsten, while the side‐on coordination via the P=C bond resulted with platinum. Decomposition of the mesityl derivative yielded an unprecedented product, which may be formed by 1,3‐H shift to the P atom, hydrophosphination of the P=C bond of a second phosphaallene and formation of a P−P bond.
Size‐Exclusion Borane‐Catalyzed Domino 1,3‐Allylic/Reductive Ireland–Claisen Rearrangements: Impact of the Electronic and Structural Parameters on the 1,3‐Allylic Shift Aptitude
Authors: Fegyverneki Dániel , Kolozsvári Natália , Molnár Dániel , Egyed Orsolya , Holczbauer Tamás , Soós Tibor 
Published: January 2019

AbstractInvited for the cover of this issue is the group of Tibor Soós at the Hungarian Academy of Sciences. The image depicts a metaphorical representation of the catalytic cycles and the size‐exclusion concept of the reported metal‐free, one‐pot reductive Ireland–Claisen rearrangement. Read the full text of the article at 10.1002/chem.201805208.
The effect of Zika virus infection in the ferret
Authors: Hutchinson Elizabeth B. , Chatterjee Mitali , Reyes Laura , Djankpa Francis T. , Valiant William G. , Dardzinski Bernard , Mattapallil Joseph J. , Pierpaoli Carlo , Juliano Sharon L. 
Published: January 2019

AbstractAlthough initial observations of infections with the Zika virus describe a mild illness, more recent reports show that infections by Zika result in neurotropism. In 2015, substantial congenital malformations were observed, with numerous infants born with microcephaly in Brazil. To study the underlying mechanism and effects of the disease, it is critical to find suitable animal models. Rodents lack an immune system parallel to humans and also have lissencephalic brains, which are likely to react differently to infections. As the smallest gyrencephalic mammal, ferrets may provide an important animal model to study the Zika virus, as their brains share many characteristics with humans. To evaluate the prospect of using ferrets to study Zika virus infection, we injected seven pregnant jills with the PR strain subcutaneously on gestational day 21, corresponding to the initiation of corticogenesis. These injections resulted in mixed effects. Two animals died of apparent infection, and all kits were resorbed in another animal that did not die. The other four animals remained pregnant until gestational day 40, when the kits were delivered by caesarian section. We evaluated the animals using CT, MRI, diffusion tensor imaging, and immunohistochemistry. The kits displayed a number of features compatible with an infection that impacted both the brain and skull. The outcomes, however, were variable and differed within and across litters, which ranged from the absence of observable abnormalities to prominent changes, suggesting differential vulnerability of kits to infection by the Zika virus or to subsequent mechanisms of neurodevelopmental disruption.