bluuebunny/crossref_metadata_2025_split huggingface dataset:
A case of empyema and septic arthritis due to Nocardia farcinica
Authors: Ishiguro Takashi , Yoshioka Hiroaki , Kawai Shoko , Katsumata Shin‐ichi , Gonoi Tohru , Takayanagi Noboru 
Published: October 2017

Key Clinical MessageSeptic arthritis due to Nocardia sp. should be suspected when a patient with risk factors such as pneumoconiosis or diabetes mellitus develops joint symptoms, especially if the patient has had nocardiosis in other sites.
Nitrite‐Enhanced Charge Transfer to and from Single Polyaniline Nanotubes
Authors: Liu Jianyun , Li Xiuting , Batchelor‐McAuley Christopher , Zhu Guodong , Compton Richard G. 
Published: October 2017

AbstractAs Liu et al. reported previously (Appl. Mater. Today 2017, 7, 239–245), the charge transfer to partially oxidized polyaniline (PANI) nanotubes in electrochemical reactions is heavily limited due to the non‐conductivity of the reduction/oxidation products. In this paper, the doping level of individual PANI nanotubes was substantially enhanced using nitrite as an electron acceptor in sulfuric acid aqueous solution as recorded by the nano‐impact method. The charge transferred to one single tube during reduction process is close to the theoretical value of 170±112 pC per tube (assuming 2‐electron reduction for the PANI tubes studied), while the charge during PANI oxidation is dramatically decreased. Reaction processes are proposed based on the oxidative properties of nitrite in acid solution. UV–visible spectroscopy analysis further confirms an oxidation–reduction reaction between PANI and nitrite. In contrast the electrochemical reaction of ensembles (21 μg cm−1) of PANI tubes on glassy carbon electrodes simply show limited electrocatalytic activity.
An {As4Cu4[Cu(H2O)]12} Cluster Incorporated within Four [Nb7O22]9− Units
Authors: Li Li , Dong Kaili , Ma Pengtao , Zhang Chao , Niu Jingyang , Wang Jingping 
Published: October 2017

AbstractA gigantic 16‐copper‐containing 28‐niobate cluster, Na14K7H5{As4Cu4[Cu(H2O)]12Nb28O109}⋅37.5 H2O (1), has been prepared by a one‐pot reaction, which is the first example of arsenic copper clusters containing polyoxoniobate, and the first tetrahedral arrangement of both the Cu cluster and the [Nb7O22]9− subunits.
Antimicrobial Peptide Structures: From Model Membranes to Live Cells
Authors: Sani Marc‐Antoine , Separovic Frances 
Published: October 2017

AbstractThe rise in antibiotic resistance has led to a renewed interest in antimicrobial peptides (AMPs) that target membranes. The mode of action of AMPs involves the disruption of the lipid bilayer and leads to growth inhibition and death of the bacteria. However, details at the molecular level of how these peptides kill bacteria and the reasons for the observed differences in selectivity remain unclear. Structural information is crucial for defining the molecular mechanism by which these peptides recognize, self‐assemble and interact with a particular lipid membrane. Solid‐state NMR is a non‐invasive technique that allows the study of the structural details of lipid–peptide and peptide–peptide interactions. Following on from studies of antibiotic and lytic peptides, gramicidin A and melittin, respectively, we investigated maculatin 1.1, an AMP from the skin of Australian tree frogs that acts against Gram‐positive bacteria. By using perdeuterated phospholipids and specifically labelled peptides, 2H, 31P and {31P}15N REDOR solid‐state NMR experiments have been used to localize, maculatin 1.1 in neutral and anionic model membranes. However, the structure, location and activity depend on the composition of the model membrane and current advances in solid‐state NMR spectroscopy now allow structure determination of AMPs in live bacteria.
Increasing the Reactivity of Diborenes: Derivatization of NHC‐Supported Dithienyldiborenes with Electron‐Donor Groups
Authors: Auerhammer Dominic , Arrowsmith Merle , Bissinger Philipp , Braunschweig Holger , Dellermann Theresa , Kupfer Thomas , Lenczyk Carsten , Roy Dipak K. , Schäfer Marius , Schneider Christoph 
Published: October 2017

AbstractA series of NHC‐supported 1,2‐dithienyldiborenes was synthesized from the corresponding (dihalo)thienylborane NHC precursors. NMR and UV/Vis spectroscopic data, as well as X‐ray crystallographic analyses, were used to assess the electronic and steric influences on the B=B double bond of various NHCs and electron‐donating substituents on the thienyl ligands. Crystallographic data showed that the degree of coplanarity of the diborene core and thienyl groups is highly dependent on the sterics of the substituents. Furthermore, any increase in the electron‐donating ability of the substituents resulted in the destabilization of the HOMO and greater instability of the resulting diborenes.
On Pentakis(pentafluoroethyl)stannate, [Sn(C2F5)5]−, and the Gas‐Free Generation of Pentafluoroethyllithium, LiC2F5
Authors: Wiesemann Markus , Klösener Johannes , Neumann Beate , Stammler Hans‐Georg , Hoge Berthold 
Published: October 2017

AbstractPentafluoroethyllithium, LiC2F5, has been established as an efficient and versatile reagent for the transfer of the pentafluoroethyl unit to a number of electrophiles. Here, the stability of this species up to −40 °C is of advantage, particularly in comparison to its smaller congener LiCF3. The usual production of LiC2F5, however, from gaseous HC2F5 or IC2F5 and strong bases requires specially designed apparatuses, which severely impeded its value as a laboratory reagent. In this contribution we communicate an alternative gas‐free and highly efficient protocol for the synthesis of LiC2F5 from the already commercialized stannate salt [PPh4][Sn(C2F5)5]. The [Sn(C2F5)5]− anion represents not only the first example of a structurally characterized hypervalent pentaalkylstannate but also serves as a precursor for the synthesis of the homoleptic tetrakis(pentafluoroethyl)stannane, Sn(C2F5)4. The reaction of the latter with n‐butyllithium provides an insight into the mechanism of LiC2F5 generation.
Historical Biogeography of endemic seed plant genera in the Caribbean: Did GAARlandia play a role?
Authors: Nieto‐Blázquez María Esther , Antonelli Alexandre , Roncal Julissa 
Published: October 2017

AbstractThe Caribbean archipelago is a region with an extremely complex geological history and an outstanding plant diversity with high levels of endemism. The aim of this study was to better understand the historical assembly and evolution of endemic seed plant genera in the Caribbean, by first determining divergence times of endemic genera to test whether the hypothesized Greater Antilles and Aves Ridge (GAARlandia) land bridge played a role in the archipelago colonization and second by testing South America as the main colonization source as expected by the position of landmasses and recent evidence of an asymmetrical biotic interchange. We reconstructed a dated molecular phylogenetic tree for 625 seed plants including 32 Caribbean endemic genera using Bayesian inference and ten calibrations. To estimate the geographic range of the ancestors of endemic genera, we performed a model selection between a null and two complex biogeographic models that included timeframes based on geological information, dispersal probabilities, and directionality among regions. Crown ages for endemic genera ranged from Early Eocene (53.1 Ma) to Late Pliocene (3.4 Ma). Confidence intervals for divergence times (crown and/or stem ages) of 22 endemic genera occurred within the GAARlandia time frame. Contrary to expectations, the Antilles appears as the main ancestral area for endemic seed plant genera and only five genera had a South American origin. In contrast to patterns shown for vertebrates and other organisms and based on our sampling, we conclude that GAARlandia did not act as a colonization route for plants between South America and the Antilles. Further studies on Caribbean plant dispersal at the species and population levels will be required to reveal finer‐scale biogeographic patterns and mechanisms.
Post aus dem Universum
Authors: Beck Alexander , Klein Ulrich , Lesch Harald 
Published: October 2017

AbstractAstrophysik: Die Milchstraße als Heimatgalaxie unserer Erde hat sie, und alle anderen Galaxien haben sie auch – großräumige kosmische Magnetfelder. Um ihre Entstehung und Entwicklung zu verstehen, kombinieren Forscher radioteleskopische Beobachtungen des Himmels mit numerischen Simulationen am Computer. Das führt sie zu neuen Erkenntnissen an den Grenzen bisherigen Wissens.
Von Hand zu Herz
Authors: Hatzfeld Christian , Koev Nataliya , Werthschützky Roland 
Published: October 2017

AbstractUntersuchungen mit dem Herzkatheter sind längst millionenfache Routine – und doch mit Risiken verbunden. Ingenieure haben nun ein Assistenzsystem entwickelt, das den Führungsdraht mit einem miniaturisierten Kraftsensor leichter und präziser navigieren lässt und dem Kardiologen haptische Rückmeldungen gibt.
#Smartphone‐Gemeinschaften
Authors: Unterstell Rembert 
Published: October 2017

AbstractWhatsApp, Snapchat oder Pokémon GO: Die Konstanzer Medienwissenschaftlerin und Heinz Maier‐Leibnitz‐Preisträgerin Isabell Otto untersucht die modernen Digitalmedien mit kulturwissenschaftlichem Esprit / Mediale Teilhabe zwischen Erwartung und Zumutung
Impact of Platinum Loading on Performance and Degradation of Polymer Electrolyte Fuel Cell Electrodes Studied in a Rainbow Stack
Authors: Gazdzicki P. , Mitzel J. , Dreizler A. M. , Schulze M. , Friedrich K. A. 
Published: October 2017

AbstractThe paper focuses on the investigation of durability and performance of a low temperature polymer electrolyte membrane fuel cell (PEMFC) stack as a function of Pt loading in automotive test conditions. Major motivations are problems related to the need to reduce the amount of Pt in membrane electrode assemblies (MEAs) in order to make PEMFC more competitive. The particular challenge is to maintain sufficiently high performance and long‐term durability. The study shows that for cathode Pt loadings below 0.2 mg cm−2 and for current densities exceeding 1 A cm−2 a sudden drop of performance is observed. The same threshold value is found for the increase of irreversible voltage losses which lead to an intense reduction of PEMFC durability for cathodic loadings below 0.2 mg cm−2. Another durability issue at cathodic Pt loadings < 0.4 mg cm−2 is the acceleration of reversible degradation, which leads to a strong voltage drop during continues fuel cell operation (i.e., without a recovery interruption).
Cultural stressors, identity development, and substance use attitudes among Hispanic immigrant adolescents
Authors: Grigsby Timothy J. , Forster Myriam , Meca Alan , Zamboanga Byron L. , Schwartz Seth J. , Unger Jennifer B. 
Published: October 2017

AbstractThe goal of this investigation was to determine whether various cultural stressors (bicultural stress, perceived discrimination, and perceived negative context of reception [PNCR]) predict positive and negative substance use attitudes, directly and indirectly through personal identity, in a sample of immigrant Hispanic adolescents. Data on cultural stressors, substance use attitudes, and covariates were collected from 302 Hispanic immigrant adolescents (152 from Miami [61% Cuban] and 150 from Los Angeles [70% Mexican]) at 3 time points. PNCR was associated with identity confusion (β = .175, p = .033). Identity confusion significantly predicted higher positive attitudes toward alcohol and other drug (AOD; β = .216, p < .001) and cigarette use (β = .191, p = .015) and mediated the relationship between PNCR with unfavorable AOD attitudes (β = −.019, 95% confidence interval [CI] [− 0.052, − 0.001]) and favorable AOD attitudes (β = 0.038, 95% CI [0.003, 0.086]). Perceptions of a negative context of reception may hinder successful personal identity formation and impact health outcomes for immigrant youth.
Development of the muscles associated with the mandibular and hyoid arches in the Siberian sturgeon, Acipenser baerii (Acipenseriformes: Acipenseridae)
Authors: Warth Peter , Hilton Eric J. , Naumann Benjamin , Olsson Lennart , Konstantinidis Peter 
Published: October 2017

AbstractThe skeleton of the jaws and neurocranium of sturgeons (Acipenseridae) are connected only through the hyoid arch. This arrangement allows considerable protrusion and retraction of the jaws and is highly specialized among ray‐finned fishes (Actinopterygii). To better understand the unique morphology and the evolution of the jaw apparatus in Acipenseridae, we investigated the development of the muscles of the mandibular and hyoid arches of the Siberian sturgeon, Acipenser baerii. We used a combination of antibody staining and formalin‐induced fluorescence of tissues imaged with confocal microscopy and subsequent three‐dimensional reconstruction. These data were analyzed to address the identity of previously controversial and newly discovered muscle portions. Our results indicate that the anlagen of the muscles in A. baerii develop similarly to those of other actinopterygians, although they differ by not differentiating into distinct muscles. This is exemplified by the subpartitioning of the m. adductor mandibulae as well as the massive m. protractor hyomandibulae, for which we found a previously undescribed portion in each. The importance of paedomorphosis for the evolution of Acipenseriformes has been discussed before and our results indicate that the muscles of the mandibular and the hyoid may be another example for heterochronic evolution.
Degradation alters the lubrication of articular cartilage by high viscosity, hyaluronic acid‐based lubricants
Authors: Bonnevie Edward D. , Galesso Devis , Secchieri Cynthia , Bonassar Lawrence J. 
Published: October 2017

ABSTRACTHyaluronic acid (HA) is widely injected as a viscosupplement in the treatment of osteoarthritis. Despite its extensive use, it is not currently known if cartilage degradation alters how HA‐based solutions lubricate the articular surface. In this study we utilized a model of cartilage degradation by IL‐1β along with a recently developed framework to study role of cartilage degradation on lubrication by clinically‐approved HA‐based lubricants with high viscosities. Cartilage explants were cultured up to 8 days with 10 ng/ml IL‐1β. After culture, samples were examined histologically, immunohistochemically, biochemically, mechanically, topographically, and tribologically. The tribological testing analyzed both boundary and mixed lubrication modes to assess individual effects of viscosity and boundary lubricating ability. Friction testing was carried out using PBS and two clinically approved HA‐based viscosupplements in a cartilage‐glass configuration. After culture with IL‐1β, boundary mode friction was elevated after both 4 and 8 days. Additionally, friction in mixed mode lubrication, where HA is most effective as a lubricant, was significantly elevated after 8 days of culture. As cartilage became rougher, softer, and more permeable after culture, the boundary mode plateau was extended, and as a result, significantly increased lubricant viscosities or sliding speeds were necessary to achieve effective mixed lubrication. Overall, this study revealed that lubrication of cartilage by HA is degradation‐dependent and coincides with changes in mechanics and roughness. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1456–1464, 2018.
Temporal variability in composition and fluxes of Yellow River particulate organic matter
Authors: Tao Shuqin , Eglinton Timothy I. , Zhang Liang , Yi Zhiwei , Montluçon Daniel B. , McIntyre Cameron , Yu Meng , Zhao Meixun 
Published: October 2017

AbstractThis study examines temporal variations of the abundance and carbon isotopic characteristics of particulate organic carbon (POC) and specific‐source compounds in the context of hydrological variability in the Yellow River. The content and bulk carbon isotopic characteristics (13C and 14C) of POC were relatively uniform over the hydrologic (seasonal) cycle. We attribute these temporally invariant geochemical characteristics to the dominant contribution of loess material to the suspended particulate matter (SPM). In contrast, molecular‐level signals revealed that hydrologic conditions exert a significant influence on the proportional contributions of petrogenic and especially fresh plant‐derived OC, while pre‐aged soil OC is mobilized via deeper erosion processes (e.g., gully erosion, mudslides) and is independent of hydrodynamics and surface runoff. A coupled biomarker‐isotope mixing model was applied to estimate the time‐varying supply of contemporary/modern biomass, pre‐aged soil, and fossil OC components to Chinese marginal seas from the Yellow River. We found that natural (e.g., precipitation) and human‐induced (e.g., water and sediment regulation) variations in hydrological regime strongly influence the flux with the magnitude of the corresponding annual fluxes of POC ranging between 0.343 ± 0.122 Mt yr−1 and 0.581 ± 0.213 Mt yr−1, but less strongly infleunce proportions of the different OC constituents. Inter‐annual differences in pre‐aged soil and fossil OC fluxes imply that extreme climate events (e.g., floods) modulate the exhumation and export of old carbon to the ocean, but the OC homogeneity in the pre‐aged mineral soil‐dominated watersheds facilitates robust predictions in terms of OC transport dynamics in the past (sediment cores) and in the future.
Kelp detritus provides high‐quality food for sea urchin larvae
Authors: Feehan Colette J. , Grauman‐Boss Beatrice C. , Strathmann Richard R. , Dethier Megan N. , Duggins David O. 
Published: October 2017

AbstractHighly productive kelps release abundant particulate organic matter into the nearshore environment due to their constant fragmentation and erosion by ocean waves. The contribution of kelp detritus to coastal planktonic food webs has not previously been examined. Here, we demonstrate that detritus derived from a dominant kelp in the Northeast Pacific, Nereocystis luetkeana, provides high‐quality food for planktonic sea urchin larvae. Our findings challenge the paradigm that phytoplankton are the main diet for zooplankton in nearshore regions, with implications for modeling of ocean production. Furthermore, at the benthic adult stage, sea urchins can destructively graze kelps causing the kelp ecosystem to collapse; hence, our results have implications for understanding feedback mechanisms that may determine the resilience of kelp ecosystems.
Alkali‐Mediated Miscibility of Gelatin/Polycaprolactone for Electrospinning Homogeneous Composite Nanofibers for Tissue Scaffolding
Authors: Zhou Qihui , Zhang Huilan , Zhou Ya , Yu Zhepao , Yuan Huihua , Feng Bei , van Rijn Patrick , Zhang Yanzhong 
Published: October 2017

AbstractElectrospun natural‐synthetic composite nanofibers, which possess favorable biological and mechanical properties, have gained widespread attention in tissue engineering. However, the development of biomimetic nanofibers of hybrids remains a huge challenge due to phase separation of the polymer blends. Here, aqueous sodium hydroxide (NaOH) solution is proposed to modulate the miscibility of a representative natural‐synthetic hybrid of gelatin (GT) and polycaprolactone (PCL) for electrospinning homogeneous composite nanofibers. Alkali‐doped GT/PCL solutions and nanofibers examined at macroscopic, microscopic, and internal molecular levels demonstrate appropriate miscibility of GT and PCL after introducing the alkali dopant. Particularly, homogeneous GT/PCL nanofibers with smooth surface and uniform diameter are obtained when aqueous NaOH solution with a concentration of 10 m is used. The fibers become more hydrophilic and possess improved mechanical properties both in dry and wet conditions. Moreover, biocompatibility experiments show that stem cells adhere to and proliferate better on the alkali‐modified nanofibers than the untreated one. This study provides a facile and effective approach to solve the phase separation issue of the synthetic‐natural hybrid GT/PCL and establishes a correlation of compositionally and morphologically homogeneous composite nanofibers with respect to cell responses.
Who benefits from fixed‐dose combinations? Two‐year statin adherence trajectories in initiators of combined amlodipine/atorvastatin therapy
Authors: Schaffer Andrea L. , Buckley Nicholas A. , Pearson Sallie‐Anne 
Published: October 2017

AbstractPurposeWe compared statin adherence in individuals initiating combined amlodipine/atorvastatin therapy as a fixed‐dose (FDC) or free combination and identified subgroups benefiting most from FDCs.MethodsWe used a 10% sample of Australian Pharmaceutical Benefits Scheme dispensing data (2005‐2015) to identify individuals initiating amlodipine and atorvastatin as an FDC (n = 3996) or free combination (n = 5434), with or without prior statin dispensing. We measured the proportion of days covered in each 30‐day period over 24 months and classified patterns of statin adherence using group‐based trajectory models. We identified predictors of adherence trajectories using logistic regression.ResultsThe median age was 71 years, and 53% were female. We identified 4 patterns of statin adherence: near‐perfect adherence (n = 5383), good adherence (n = 1893), declining adherence (n = 1247), and early nonadherence (n = 907). Compared with the free combination, FDC initiators were more likely to have near‐perfect adherence if they were previously statin adherent irrespective of amlodipine dose (amlodipine 5 mg: OR = 1.61, 95% CI 1.38‐1.87; amlodipine 10 mg: OR = 2.39, 95% CI 1.63‐3.51) or they were previously statin nonadherent and initiated on the 5 mg amlodipine dose (OR = 1.87, 95% CI 1.50‐2.32). Statin‐naïve individuals initiating on the FDC with 10 mg amlodipine were less likely to have near‐perfect adherence (OR = 0.60, 95% CI 0.41‐0.88) and more likely to have early nonadherence (OR = 1.73, 95% CI 1.17‐2.55).ConclusionsThe amlodipine/atorvastatin FDC was associated with greater statin adherence among prevalent statin users, and individuals who initiated on lower amlodipine doses. The FDCs did not improve adherence in statin‐naïve individuals and in some cases resulted in poorer adherence.
Isolation and Characterisation of a Halotolerant ω‐Transaminase from a Triassic Period Salt Mine and Its Application to Biocatalysis
Authors: Kelly Stephen A. , Megaw Julianne , Caswell Jill , Scott Christopher J. , Allen Christopher C. R. , Moody Thomas S. , Gilmore Brendan F. 
Published: October 2017

AbstractChiral amines are valuable intermediates for the pharmaceutical industry, with up to 40% of current pharmaceuticals containing an amine functionality. However, their syntheses by conventional chemical methods often suffer from a number of key drawbacks. Transaminases (TAms) are pyridoxal phosphate (PLP) dependent enzymes capable of transferring an amine group to a prochiral ketone, offering a green and economically viable alternative to chiral amine production. Despite some high profile successes, TAms suffer from limited substrate scope and the ability to function under challenging conditions often required in reaction processes. Mining of untapped, extremophilic environments represents a viable approach in the search for novel enzymes. We report the cloning and expression of an (S)‐selective ω‐TAm from a Halomonas sp. (Ad2‐TAm), isolated from an extreme hypersaline environment formed during the Triassic period (circa 220 mya). Ad2‐TAm exhibits an ability to convert a range of structurally diverse aldehyde and ketone substrates, with no decrease in conversion up to 1.5 M (8.8%) NaCl. The enzyme is also tolerant to the presence of organic cosolvents up to 30% and accepts a range of amino donors. These characteristics make Ad2‐TAm a promising candidate for industrial applications, whilst also highlighting the value of extreme environments as a source of novel enzymes for the pharmaceutical industry as a whole.