bluuebunny/crossref_metadata_2025 huggingface dataset:
An Argon–Oxygen Covalent Bond in the ArOH+ Molecular Ion
Authors: Wagner J. Philipp , McDonald David C. , Duncan Michael A.
Published: March 2018

The OH+ cation is a well‐known diatomic for which the triplet (3Σ−) ground state is 50.5 kcal mol−1 more stable than its corresponding singlet (1Δ) excited state. However, the singlet forms a strong donor–acceptor bond to argon with a bond energy of 66.4 kcal mol−1 at the CCSDT(Q)/CBS level, making the singlet ArOH+ cation 3.9 kcal mol−1 more stable than the lowest energy triplet complex. Both singlet and triplet isomers of this molecular ion were prepared in a cold molecular beam using different ion sources. Infrared photodissociation spectroscopy in combination with messenger atom tagging shows that the two spin isomers exhibit completely different spectral signatures. The ground state of ArOH+ is the predicted singlet with a covalent Ar−O bond.
A latent class analysis of self‐identified reasons for experiencing homelessness: Opportunities for prevention
Authors: Barile John P. , Pruitt Anna Smith , Parker Josie L.
Published: March 2018

Individuals experience homelessness due to a vast number of factors. Therefore, the methods used to prevent individuals from experiencing homelessness should match their diverse needs. This study utilized survey data obtained from 577 adults experiencing homelessness to identify self‐reported causes of homelessness. A latent class analysis was conducted in order to identify classes or subgroups of respondents with distinct patterns of reported causes of homelessness. A latent class analysis is a person‐centred statistical approach that is used to determine groups of individuals who share similar characteristics. Findings from this analysis identified 5 distinct classes based on individuals' responses to 19 potential vulnerabilities or events that contributed to experiencing homelessness. Individuals tended to cluster around issues associated with (a) disability or physical health issues (4%), (b) substance abuse or mental health issues (30%), (c) report major life changes (3%), (d) financial crises (7%), or (e) employment difficulties (55%). Significant group differences occurred across military veteran status, history of homelessness, depression, and health‐related quality of life. Results for these analyses suggest that individuals report notable differences in their reasons for becoming homeless and therefore require unique preventative solutions.
Sequence‐Dependent Diastereospecific and Diastereodivergent Crosslinking of DNA by Decarbamoylmitomycin C
Authors: Aguilar William , Paz Manuel M. , Vargas Anayatzinc , Clement Cristina C. , Cheng Shu‐Yuan , Champeil Elise
Published: March 2018

Mitomycin C (MC), a potent antitumor drug, and decarbamoylmitomycin C (DMC), a derivative lacking the carbamoyl group, form highly cytotoxic DNA interstrand crosslinks. The major interstrand crosslink formed by DMC is the C1′′ epimer of the major crosslink formed by MC. The molecular basis for the stereochemical configuration exhibited by DMC was investigated using biomimetic synthesis. The formation of DNA‐DNA crosslinks by DMC is diastereospecific and diastereodivergent: Only the 1′′S‐diastereomer of the initially formed monoadduct can form crosslinks at GpC sequences, and only the 1′′R‐diastereomer of the monoadduct can form crosslinks at CpG sequences. We also show that CpG and GpC sequences react with divergent diastereoselectivity in the first alkylation step: 1“S stereochemistry is favored at GpC sequences and 1′′R stereochemistry is favored at CpG sequences. Therefore, the first alkylation step results, at each sequence, in the selective formation of the diastereomer able to generate an interstrand DNA‐DNA crosslink after the ”second arm“ alkylation. Examination of the known DNA adduct pattern obtained after treatment of cancer cell cultures with DMC indicates that the GpC sequence is the major target for the formation of DNA–DNA crosslinks in vivo by this drug.
Can Remote N‐Heterocyclic Carbenes Coordinate with Main Group Elements? Synthesis, Structure, and Quantum Chemical Analysis of N+‐Centered Complexes
Authors: Patel Neha , Arfeen Minhajul , Sood Radhika , Khullar Sadhika , Chakraborti Asit K. , Mandal Sanjay K. , Bharatam Prasad V.
Published: March 2018

Remote N‐heterocyclic carbenes (rNHCs), such as N‐methyl‐4‐pyridylidene, are known to form coordination complexes with TMs. Herein, it is established that rNHCs can also coordinate to the N+ centre. Synthesis of some novel divalent NI complexes with the general formula (rNHC)→N+←(NHC) and (rNHC)→N+←(rNHC) was achieved, and X‐ray diffraction studies supported the coordination bond character between the rNHCs and the N+ centre. Quantum chemical analysis established the presence of divalent NI character at the central nitrogen in these systems.
Tuning the Mesomorphism and Redox Response of Anionic‐Ligand‐Based Mixed‐Valent Nickel(II) Complexes by Alkyl‐Substituted Quaternary Ammonium Cations
Authors: Nakamura Yuichi , Matsumoto Takeshi , Sakazume Yasutaka , Murata Junnosuke , Chang Ho‐Chol
Published: March 2018

The combination of the redox‐active mesogenic anion [NiII(Bdt)(BdtSQ)]− (Bdt=1,2‐benzenedithiolato; BdtSQ=1,2‐dithia‐semi‐benzoquinonato) with alkyl‐substituted ammonium cations afforded a series of redox‐active ionic complexes of the type [NR4][NiII(Bdt)(BdtSQ)] [R=nC16H33 (NC164Ni) and C8,10 (NC8,104Ni); C8,10=6‐octylhexadecyl] or [NMe2R2][NiII(Bdt)(BdtSQ)] [R=nC16H33 (NMe2C162Ni) and C8,10 (NMe2C8,102Ni)]. X‐ray crystallographic analyses of NMe2C162Ni and NC164Ni revealed the formation of cation‐dependent integrated ionic layers separated by interdigittated alkyl chains. Complexes NMe2C162Ni and NC164Ni commonly form crystalline phases at room temperature, whereas complexes NMe2C8,102Ni and NC8,104Ni, which contain branched alkyl chains, form a metastable mesophase and an amorphous phase at the same temperature, respectively. Furthermore, complexes NMe2C162Ni, NMe2C8,102Ni, and NC164Ni commonly form a smectic A phase (SmA) at 375, 317, and 342 K, respectively. For the four complexes, well‐defined cyclic voltammetry responses, derived from ligand‐based oxidation and reduction, were observed in solution and the condensed phases, that is, upon casting these complexes on an indium‐doped tin oxide working electrode. The present study demonstrates the tunability of the mesomorphism of ionic molecular assemblies composed of alkyl‐substituted quaternary ammonium cations, while maintaining the well‐defined redox responses of the anions even in the condensed phases.
Amyloid‐Like Fibrillary Morphology Originated by Tyrosine‐Containing Aromatic Hexapeptides
Authors: Diaferia Carlo , Balasco Nicole , Sibillano Teresa , Ghosh Moumita , Adler‐Abramovich Lihi , Giannini Cinzia , Vitagliano Luigi , Morelli Giancarlo , Accardo Antonella
Published: March 2018

Phenylalanine‐based nanostructures have attracted the attention of the material science community for their functional properties. These properties strongly depend on the hierarchic organization of the nanostructure that in turn can be finely tuned by punctual chemical modifications of the building blocks. Herein, we investigate how the partial or the complete replacement of the Phe residues in PEG8‐(Phe)6 (PEG8‐F6) with tyrosines to generate PEG8‐(Phe‐Tyr)3 (PEG8‐(FY)3) or PEG8‐(Tyr)6 (PEG8‐Y6) affects the structural/functional properties of the nanomaterial formed by the parental compound. Moreover, the effect of the PEG derivatization was evaluated through the characterization of the peptides without the PEG moiety (Tyr)6 (Y6) and (Phe‐Tyr)3 ((FY)3). Both PEG8‐Y6 and PEG8‐(FY)3 can self‐assemble in water at micromolar concentrations in β‐sheet‐rich nanostructures. However, WAXS diffraction patterns of these compounds present significant differences. PEG8‐(FY)3 shows a 2D WAXS oriented fiber diffraction profile characterized by the concomitant presence of a 4.7 Å meridional and a 12.5 Å equatorial reflection that are generally associated with cross‐β structure. On the other hand, the pattern of PEG8‐Y6 is characterized by the presence of circles typically observed in the presence of PEG crystallization. Molecular modeling and dynamics provide an atomic structural model of the peptide spine of these compounds that is in good agreement with WAXS experimental data. Gelation phenomenon was only detected for PEG8‐(FY)3 above a concentration of 1.0 wt % as confirmed by storage (G′≈100 Pa) and loss (G′′≈28 Pa) moduli in rheological studies. The cell viability on CHO cells of this soft hydrogel was certified to be 90 % after 24 hours of incubation.
Axial vs. Equatorial Ligand Rivalry in Controlling the Reactivity of Iron(IV)‐Oxo Species: Single‐State vs. Two‐State Reactivity
Authors: Kumar Ravi , Ansari Azaj , Rajaraman Gopalan
Published: March 2018

High‐valent iron‐oxo species are known for their very high reactivity, and this aspect has been studied in detail over the years. The role of axial ligands in fine‐tuning the reactivity of the iron(IV)‐oxo species has been particularly well studied. The corresponding role of equatorial ligands, however, has rarely been explored, and is of prime importance in the development of non‐heme chemistry. Here, we have undertaken detailed DFT calculations on [(LNHC)FeIV(O)(CH3CN)]2+ (1; LNHC=3,9,14,20‐tetraaza1,6,12,17‐tetraazoniapenta‐cyclohexacosane‐1(23),4,6(26),10,12(25),15,17(24),21‐octaene) in comparison to compound II of cytochrome P450 [(porphyrin)FeIV(O)(SH)]− (2) to probe this aspect. The electronic structures of 1 and 2 are found to vary significantly, implying a large variation in their reactivities. In particular, the strong equatorial ligand present in 1 significantly destabilizes the quintet states as compared to species 2. To fully understand the reactivity pattern of these species, we have modelled the hydroxylation of methane by both 1 and 2. Our calculations reveal that 1 reacts via a low‐lying S=1 π pathway, and that the generally available S=2 σ pathway is not energetically accessible. In addition to having a significant barrier for C−H bond activation, the ‐OH rebound step is also computed to have a large barrier height, leading to a marked difference in reactivity between these two species. Of particular relevance here is the observation of pure triplet‐state reactivity for 1. We have also attempted to test the role of axial ligands in fine‐tuning the reactivity of 1, and our results demonstrate that, in contrast to heme systems, the axial ligands in 1 do not significantly influence the reactivity. This highlights the importance of designing equatorial ligands to fine‐tune reactivity of high‐valent iron(IV)‐oxo species.
A Rapid Colorimetric Method to Visualize Protein Interactions
Authors: Liu Bing , Wang Zhihao , Lan Ling , Yang Qianfan , Zhang Peipei , Shi Lei , Lang Yunhe , Tabib‐Salazar Aline , Wigneshweraraj Sivaramesh , Zhang Jiye , Wang Yawen , Tang Yalin , Matthews Steve , Zhang Xiufeng
Published: March 2018

As key molecules in most biological pathways, proteins physically contact one or more biomolecules in a highly specific manner. Several driving forces (i.e., electrostatic and hydrophobic) facilitate such interactions and a variety of methods have been developed to monitor these processes both in vivo and in vitro. In this work, a new method is reported for the detection of protein interactions by visualizing a color change of a cyanine compound, a supramolecule complex of 3,3‐di‐(3‐sulfopropyl)‐4,5,4′,5′‐dibenzo‐9‐methyl‐thiacarbocyanine triethylammonium salt (MTC). Nuclear magnetic resonance (NMR) studies suggest that the hydrophobic nature of the protein surfaces drives MTC into different types of aggregates with distinct colors. When proteins interact with other biomolecules, the hydrophobic surface of the complex differs, resulting in a shift in the form of MTC aggregation, which results in a color change. As a result, this in vitro method has the potential to become a rapid tool for the confirmation of protein–biomolecule interactions, without the requirements for sophisticated instrumentation or approaches.
Manipulating Clusters by Use of Competing N,O‐Chelating Ligands: A Combined Crystallographic, Mass Spectrometric, and DFT Study
Authors: Zheng Hui‐Li , Chen Xue‐Li , Li Tian , Yin Zheng , Zhang Yuexing , Kurmoo Mohamedally , Zeng Ming‐Hua
Published: March 2018

Two heptanuclear discs, [Co7(L1)6(CH3O)6]2+ (Co7‐L1) and [Co7(L2)12](ClO4)2 (Co7‐L2), have been prepared by the reaction of [Co(H2O)6](ClO4)2 with Schiff base HL1 (HL1=2‐methoxy‐6‐[(methylimino)methyl]phenolate) or benzimidazole derivative HL2 (HL2=(1H‐benzo[d]imidazol‐2‐yl)methanolate), respectively, at room temperature. In contrast, the reaction of [Co(H2O)6](ClO4)2 with a mixture of the two ligands, having similar coordination ability but different shapes, resulted in the butterfly‐structured tetranuclear cobalt cluster [Co4(L1)2(L2)4](ClO4)2⋅2H2O (Co4). Electrospray ionization mass spectrometry (ESI‐MS) analysis in real time revealed the {Co1}→{Co2}→{Co4}→{Co7} stepwise assembly when a single ligand was employed, but when both ligands were used only {Co4} was obtained, an intermediate of the former reactions. Interestingly, ligand competition was evidenced in the assembly process of the reaction with two ligands; for example, [Co4(L1)4(L2)2]2+ and [Co4(L1)3(L2)3]2+ were the primary clusters observed at the beginning of the reaction, but [Co4(L1)2(L2)4]2+ was the final product. This observation suggests ligand exchange is taking place, and DFT calculations confirmed that these transformations were possible. By varying the ratio of ligands, the abundance of a certain species in the competitive reaction could be controlled.
Efficient Detection of Structure and Dynamics in Unlabeled RNAs: The SELOPE Approach
Authors: Schlagnitweit Judith , Steiner Emilie , Karlsson Hampus , Petzold Katja
Published: March 2018

The knowledge of structure and dynamics is crucial to explain the function of RNAs. While nuclear magnetic resonance (NMR) is well suited to probe these for complex biomolecules, it requires expensive, isotopically labeled samples, and long measurement times. Here we present SELOPE, a new robust, proton‐only NMR method that allows us to obtain site‐specific overview of structure and dynamics in an entire RNA molecule using an unlabeled sample. SELOPE simplifies assignment and allows for cost‐effective screening of the response of nucleic acids to physiological changes (e.g. ion concentration) or screening of drugs in a high throughput fashion. This single technique allows us to probe an unprecedented range of exchange time scales (the whole μs to ms motion range) with increased sensitivity, surpassing all current experiments to detect chemical exchange. For the first time we could describe an RNA excited state using an unlabeled RNA.
Spiro Bicyclic Guanidino Compounds from Pufferfish: Possible Biosynthetic Intermediates of Tetrodotoxin in Marine Environments
Authors: Ueyama Nozomi , Sugimoto Keita , Kudo Yuta , Onodera Ken‐ichi , Cho Yuko , Konoki Keiichi , Nishikawa Toshio , Yotsu‐Yamashita Mari
Published: March 2018

Tetrodotoxin (TTX, 1) is a potent neurotoxin that is widely found in both terrestrial and marine animals; however, the biosynthetic pathway and genes for TTX have not yet been elucidated. Previously, we proposed that TTX originated from a monoterpene; this hypothesis was based on the structures of cyclic guanidino compounds that are commonly found in toxic newts. However, these compounds have not been detected in marine organisms. Instead, a series of deoxy analogues of TTX were found in toxic marine animals; thus, we further screened for TTX‐related compounds in marine animals. Herein, we report seven novel spiro bicyclic guanidino compounds 2–8 that were isolated from the pufferfish Tetraodon biocellatus. In compounds 2–5 and 7–8, a six‐membered cyclic guanidino amide is spiro‐fused with 2,4‐dimethyl cyclohexane, whereas in compound 6, the same cyclic guanidino amide is spiro‐fused with 2,3,5‐trimethylcyclopentane. Compounds 2–5 and 7–8 have the same carbon skeleton and relative configuration as TTX. Thus, we proposed that compounds 2–8 are biosynthetic intermediates of TTX in marine environments. TTX could be biosynthetically derived from compound 7 via intermediates 2–5 through several oxidations, amide hydrolysis, and formation of the hemiaminal and lactone found in 5,6,11‐trideoxyTTX, the major TTX analogue, whereas compounds 6 and 8 might be shunt products. LC‐MS analysis confirmed the wide distribution of compounds 2, 3, or both in TTX‐containing marine animals, namely pufferfish, crab, octopus, and flatworm, but compounds 2–8 were not detected in newts.
Synthesis of l‐[4‐11C]Asparagine by Ring‐Opening Nucleophilic 11C‐Cyanation Reaction of a Chiral Cyclic Sulfamidate Precursor
Authors: Xu Youwen , Cankaya Aylin Sibel , Hoque Ruma , Lee So Jeong , Shea Colleen , Kersting Lena , Schueller Michael , Fowler Joanna S. , Szalda David , Alexoff David , Riehl Barbara , Gleede Tassilo , Ferrieri Richard A. , Qu Wenchao
Published: March 2018

The development of a convenient and rapid method to synthesize radiolabeled, enantiomerically pure amino acids (AAs) as potential positron emission tomography (PET) imaging agents for mapping various biochemical transformations in living organisms remains a challenge. This is especially true for the synthesis of carbon‐11‐labeled AAs given the short half‐life of carbon‐11 (11C, t1/2=20.4 min). A facile synthetic pathway to prepare enantiomerically pure 11C‐labeled l‐asparagine was developed using a partially protected serine as a starting material with a four‐step transformation providing a chiral five‐membered cyclic sulfamidate as the radiolabeling precursor. Its structure and absolute configuration were confirmed by X‐ray crystallography. Utilizing a [11C]cyanide nucleophilic ring opening reaction followed by selective acidic hydrolysis and deprotection, enantiomerically pure l‐[4‐11C]asparagine was synthesized. Further optimization of reaction parameters, including base, metal ion source, solvent, acid component, reaction temperature and reaction time, a reliable two‐step method for synthesizing l‐[4‐11C]asparagine was presented: within a 45±3 min (n=5, from end‐of‐bombardment), the desired enantiomerically pure product was synthesized with the initial nucleophilic cyanation yield of 69±4 % (n=5) and overall two‐step radiochemical yield of 53±2 % (n=5) based on starting [11C]HCN, and with radiochemical purity of 96±2 % (n=5).
Machine learning–aided exploration of relationship between strength and elastic properties in ascending thoracic aneurysm
Authors: Luo Yuanming , Fan Zhiwei , Baek Stephen , Lu Jia
Published: March 2018

Machine learning was applied to classify tension‐strain curves harvested from inflation tests on ascending thoracic aneurysm samples. The curves were classified into rupture and nonrupture groups using prerupture response features. Two groups of features were used as the basis for classification. The first was the constitutive parameters fitted from the tension‐strain data, and the second was geometric parameters extracted from the tension‐strain curve. Based on the importance scores provided by the machine learning, implications of some features were interrogated. It was found that (1) the value of a constitutive parameter is nearly the same for all members in the rupture group and (2) the strength correlates strongly with a tension in the early phase of response as well as with the end stiffness. The study suggests that the strength, which is not available without rupturing the tissue, may be indirectly inferred from prerupture response features.
ANSYS‐MATLAB co‐simulation of mucus flow distribution and clearance effectiveness of a new simulated cough device
Authors: Ren Shuai , Shi Yan , Cai Maolin , Zhao Hongmei , Zhang Zhaozhi , Zhang Xiaohua Douglas
Published: March 2018

Coughing is an irritable reaction that protects the respiratory system from infection and improves mucus clearance. However, for the patients who cannot cough autonomously, an assisted cough device is essential for mucus clearance. Considering the low efficiency of current assisted cough devices, a new simulated cough device based on the pneumatic system is proposed in this paper. Given the uncertainty of airflow rates necessary to clear mucus from airways, the computational fluid dynamics Eulerian wall film model and cough efficiency (CE) were used in this study to simulate the cough process and evaluate cough effectiveness. The Ansys‐Matlab co‐simulation model was set up and verified through experimental studies using Newtonian fluids. Next, model simulations were performed using non‐Newtonian fluids, and peak cough flow (PCF) and PCF duration time were analyzed to determine their influence on mucus clearance. CE growth rate (λ) was calculated to reflect the CE variation trend. From the numerical simulation results, we find that CE rises as PCF increases while the growth rate trends to slow as PCF increases; when PCF changes from 60 to 360 L/min, CE changes from 3.2% to 51.5% which is approximately 16 times the initial value. Meanwhile, keeping a long PCF duration time could greatly improve CE under the same cough expired volume and PCF. The results indicated that increasing the PCF and PCF duration time can improve the efficiency of mucus clearance. This paper provides a new approach and a research direction for control strategy in simulated cough devices for airway mucus clearance.
Remarkable Confinement Effect of Nanofiber in Carbon Nanotubes for Dehydrogenative Coupling of Alcohols with α‐Diaminobenzene: A Route for the Synthesis of Benzimidazoles
Authors: Shaikh Melad , Yadav Richa , Tyagi Pawan K. , Mishra Lallan , Ranganath Kalluri V. S.
Published: March 2018

Magnetic nanofiber (MNF) confined in carbon nanotubes (CNTs) has been efficiently used in dehydrogenative coupling. A remarkable effect has been observed in the coupling of alcohols with diaminobenzene. This represents a new method to produce benzimidazoles in high yields under heterogeneous conditions without using expensive metals such as Pt, Ru, and Ir. This MNF was synthesized by reacting magnetite nanoparticles (MNPs) with various spacers such as di‐, tri‐ and tetracarboxylic acids.
An adaptive approach to create on‐demand color schemes for mapping quantitative geographic data
Authors: Wu Mingguang , Chen Taisheng , Wang Hong , Lv Guonian , Zhu A‐Xing
Published: March 2018

Creating a satisfying quantitative color scheme is challenging for both novices and experts. Geovisualization often suffers from the misuse and misunderstanding of quantitative color schemes. This article presents an adaptive method to create ready‐to‐use quantitative schemes. A probability‐based method for color selection is presented to quantify the selection of quantitative colors from learning samples of varying popularity. To shape the color transitions, a regression analysis is performed to fit the mathematical curves for the transitions of hue, saturation, and brightness. Finally, the problem of creating satisfying quantitative schemes is translated into a multiconstraint optimization problem. A discretize‐and‐filter method is also presented to solve the optimization problem of globally identifying a suitable scheme in a continuous color space. The proposed method is evaluated with a case study, and the results indicate that the proposed method can derive satisfying schemes. In addition, the proposed method is adaptive to mapping feature, target reader and target device.
Costs and benefits of admixture between foreign genotypes and local populations in the field
Authors: Shi Jun , Joshi Jasmin , Tielbörger Katja , Verhoeven Koen J. F. , Macel Mirka
Published: March 2018

Admixture is the hybridization between populations within one species. It can increase plant fitness and population viability by alleviating inbreeding depression and increasing genetic diversity. However, populations are often adapted to their local environments and admixture with distant populations could break down local adaptation by diluting the locally adapted genomes. Thus, admixed genotypes might be selected against and be outcompeted by locally adapted genotypes in the local environments. To investigate the costs and benefits of admixture, we compared the performance of admixed and within‐population F1 and F2 generations of the European plant Lythrum salicaria in a reciprocal transplant experiment at three European field sites over a 2‐year period. Despite strong differences between site and plant populations for most of the measured traits, including herbivory, we found limited evidence for local adaptation. The effects of admixture depended on experimental site and plant population, and were positive for some traits. Plant growth and fruit production of some populations increased in admixed offspring and this was strongest with larger parental distances. These effects were only detected in two of our three sites. Our results show that, in the absence of local adaptation, admixture may boost plant performance, and that this is particularly apparent in stressful environments. We suggest that admixture between foreign and local genotypes can potentially be considered in nature conservation to restore populations and/or increase population viability, especially in small inbred or maladapted populations.
Fish presence and inter‐patch connectivity interactively alter the size of emergent insects in experimental enclosures
Authors: Pitcher Kristopher A. , Soluk Daniel A.
Published: March 2018

Structural habitat complexity (SHC) and functional habitat connectivity (FHC) are the basic components that make up the physical architecture of an ecosystem, and can have substantial impacts on predator–prey interactions. These structural components influence animal behaviors such as inter‐patch movement, foraging, and competition, and can impact community structure/dynamics in terrestrial and aquatic ecosystems. The effects of SHC and FHC on predator–prey dynamics within an ecosystem may also have important cascading effects on neighboring ecosystems by altering the movement of individuals across ecosystem boundaries. For example, when aquatic insects emerge as adults, they enter terrestrial ecosystems where they become an important food resource for terrestrial predators. Using a multiple patch, predator enclosure design in ponds, we tested whether altering intra‐patch plant stem densities (SHC) and inter‐patch distances (FHC) would influence the impact a predatory fish has on the biomass, quality, and trophic composition of emergent insects. As expected, fish significantly reduced emergent insect biomass (33% ± 7.6, mean ± SE). Intra‐patch stem densities (SHC) did not significantly alter fish effects; however, inter‐patch distance (FHC) did significantly alter the impact of fish on the size of some emergent insects. Damselflies that emerged in treatments with fish present and shorter inter‐patch distances were significantly larger, 4.1 ± 0.1 mg/m2 compared to 3.3 mg/m2 ± 0.1 in the long/fish treatments. In fish treatments, this effect on damselfly size resulted in greater reductions in total emergent insect biomass in long inter‐patch distance treatments (47.3% ± 6.9) compared to short inter‐patch distance treatments (20.5% ± 12.4). Our results suggest that physical components of a habitat, such as inter‐patch distances, have important impacts on predator–prey dynamics within habitats. These altered predator–prey dynamics can then have cascading effects on adjacent habitats by influencing the abundance, trophic composition, and quality of exported trophic subsidies.
Anticoagulation in heart failure without atrial fibrillation: gaps and dilemmas in current clinical practice
Authors: Siliste Roxana‐Nicoleta , Antohi Elena‐Laura , Pepoyan Sergey , Nakou Eleni , Vardas Panos
Published: March 2018

Data from observational and post‐hoc analyses suggest that heart failure (HF) itself may be associated with higher risk of thromboembolic events compared to populations without HF. Although oral anticoagulants (OACs) might be a therapeutic option in individual cases, anticoagulation therapy in HF patients in sinus rhythm is not generally recommended, as the implementation of OACs in clinical practice in this HF population is not supported by large randomized clinical trials to date. Indeed, the available data suggest that the risk of major bleeding overshadows the potential anti‐thromboembolic benefit of OACs in HF patients in sinus rhythm with no net beneficial effect on mortality rates. In this review we explore the current available evidence for the clinical outcomes of anticoagulation therapy in patients with HF in sinus rhythm, highlighting the current gaps in knowledge, which may guide the design of future randomized clinical trials focusing on the efficacy and safety of anticoagulant therapy in this HF population.
Synthesis and Spectroscopy of Benzylamine‐Substituted BODIPYs for Bioimaging
Authors: Ripoll Consuelo , Cheng Cheng , Garcia‐Fernandez Emilio , Li Jin , Orte Angel , Do Hainam , Jiao Lijuan , Robinson David , Crovetto Luis , González‐Vera Juan A. , Talavera Eva M. , Alvarez‐Pez Jose M. , Boens Noël , Ruedas‐Rama María Jose
Published: March 2018

Three new boron dipyrromethene (BODIPY) dyes substituted with a benzylamino group at the 3‐position have been synthesized from halogenated BODIPYs by nucleophilic substitution. The spectroscopic and photophysical properties have been explored in different solvents and have been compared with an analogous 8‐benzylaminoBODIPY derivative. The position of the benzylamino group has a significant influence on the spectral band positions, fluorescence quantum yields, and fluorescence lifetimes. The 8‐benzylaminoBODIPY emits in the blue range, whereas the 3‐substituted shows green fluorescence. Additionally, the extension of the conjugation at the 5‐position of 3‐benzylaminoBODIPY produces a bathochromic shift of the absorption and emission spectra. The effect of solvents on their spectroscopic features has been investigated using the generalized Catalán solvent scales. Quantum‐chemical calculations have been performed to assess the effect of the position of the substitution on the spectroscopic properties. Finally, the BODIPY dyes have been employed as probes in fluorescence lifetime imaging of living cells, demonstrating their high potential for bioimaging.
The association between patient–professional partnerships and self‐management of chronic back pain: A mixed methods study
Authors: Fu Y. , Yu G. , McNichol E. , Marczewski K. , Closs S.J.
Published: March 2018

Background

Self‐management is recommended for patients with chronic back pain. Health professionals’ support for self‐management can be more effective when working in partnership with patients. The aim of this study was to investigate the associations between patient–professional partnerships and the self‐management of chronic back pain.

Methods

An explanatory sequential mixed methods study was undertaken. Adults with chronic back pain referred to pain management clinics participated at baseline and 3‐month follow‐up. Their pain severity, partnerships with health professionals and self‐management ability were measured. Hierarchical linear regression was undertaken to examine the strength of the associations between partnerships and self‐management. A subsample was interviewed about experiences of the impact of patient–professional partnerships on their self‐management ability, using a grounded theory approach.

Results

A total of 147 patients were recruited and 103 (70%) patients completed the follow‐up. A strong association (p < 0.001) was detected between patient–professional partnerships and all dimensions of self‐management ability. This was validated by interviews with a subsample of 26 patients. Four themes emerged as follows: connecting with health professionals, being supported through partnerships, feeling positive and making progress towards self‐management, and acknowledging the impact but feeling no difference.

Conclusions

Developing a partnership in care may improve patients’ ability to gain knowledge, manage side effects and symptoms and adhere to treatment. It helped strengthen health professionals’ support and produce a sense of safety for patients. Guiding health professionals in building partnerships where expectations are acknowledged and tailored information and support are provided could be considered as part of the standard education and training.

Significance

This study identified and validated strong associations between patient–professional partnerships and self‐management. Support for self‐management alone may not be sufficient, and building partnerships where patients and professionals work together towards agreed goals make an essential contribution to helping increase patients’ ability to self‐manage chronic back pain.
Sensitive and Selective Electrochemical Determination of L‐Cysteine Based on Cerium Oxide Nanofibers Modified Screen Printed Carbon Electrode
Authors: Cao Fei , Dong Qiuchen , Li Caolong , Kwak Dongwook , Huang Yikun , Song Donghui , Lei Yu
Published: March 2018

A novel L‐cysteine (CysH) electrochemical sensor based on CeO2 nanofibers (NFs) modified screen printed carbon electrodes (SPCEs) was developed. The morphology and the structure of the as‐prepared CeO2 NFs were first characterized using scanning electron microscopy (SEM) and X‐ray diffraction pattern (XRD), respectively. The electrochemical and electrocatalytic performances of the CeO2 NFs modified SPCEs were then evaluated using cyclic voltammetry and amperometry. Experimental results showed that the CeO2 NFs modified SPCEs possess excellent electrocatalytic activity toward the detection of CysH. Specifically, the developed electrochemical sensor demonstrated a high sensitivity of 120 μA mM−1 cm−2, a low detection limit of 20 nM (signal to noise ratio of 3) and a wide linear range up to 200 μM for the determination of CysH, which are among the best values reported in literature. In addition, good selectivity and outstanding intra‐ and inter‐electrode reproducibility have also been observed. Furthermore, the developed CysH sensor was applied to detect CysH spiked into human serum samples with remarkable accuracy. All these features indicate that CeO2 NFs hold great promise in the development of high performance electrochemical sensor for CysH.
Geochemical characterization, petrogenesis, and emplacement tectonics of Paleoproterozoic high‐Ti and low‐Ti mafic intrusive rocks from the western Arunachal Himalaya, northeastern India and their possible relation to the ~1.9 Ga LIP event of the Indian shield
Authors: Srivastava Rajesh K. , Samal Amiya K.
Published: March 2018

Paleoproterozoic mafic intrusive rocks from the western Arunachal Himalaya have been studied for understanding their petrogenesis and tectonic environment, in which they were emplaced, with the help of their bulk‐rock major, trace, and rare‐earth elements (REE) compositions. These mafic intrusive rocks, mostly small bodies of dykes, sills, and lenses, are exposed in the Higher as well as the Lesser Himalaya sequences. Geochemically, 2 suites of rocks are identified and grouped into high‐titanium and low‐titanium mafic intrusive rocks. High‐titanium mafic intrusive (HTMI) samples have comparatively low Mg number (Mg#) and high high‐field strength element contents in comparison to low‐titanium mafic intrusive (LTMI) rocks. Multielements and REE patterns for these two identified groups are distinct. The LTMI and HTMI were originally spatially separated at the time of their emplacement and believed that probably they have been juxtaposed during the Himalayan orogeny by crustal shortening through development of imbricated thrusts. It is perceived that the HTMI and LTMI have different petrogenetic histories and are derived from two different melts; however, they are postulated to be parts of the same igneous province. Geochemical characteristics do not support any serious effect of crustal contamination; however, interaction with metasomatized lithospheric mantle cannot be discounted. Trace element petrogenetic modelling suggests derivation of the LTMI samples from a parental magma generated in spinel stability field (thin lithosphere) through a ~20–25% melting of a lherzolite mantle source, whereas the HTMI samples were derived from ~5–10% melting of a similar mantle source but from garnet stability field (thick lithosphere). Widespread Paleoproterozoic mafic events in the Indian shield such as Bastanar dyke swarm in the Bastar and the Hampi dyke swarm (also includes Pulivendla sills in the Cuddapah Basin) in the eastern Dharwar Craton together with mafic intrusive and extrusive rocks in the Himalayan region suggest presence of a large igneous province at ~1.9 Ga.
Suicide among nursing home residents in Australia: A national population‐based retrospective analysis of medico‐legal death investigation information
Authors: Murphy Briony J. , Bugeja Lyndal C. , Pilgrim Jennifer L. , Ibrahim Joseph E.
Published: March 2018

Objectives

Suicide among nursing home residents is a growing public health concern, currently lacking in empirical research. This study aims to describe the frequency and nature of suicide among nursing home residents in Australia.

Methods

This research comprised a national population‐based retrospective analysis of suicide deaths among nursing home residents in Australia reported to the Coroner between July 2000 and December 2013. Cases were identified using the National Coronial Information System, and data collected from paper‐based coroners' records on individual, incident, and organizational factors, as well as details of the medico‐legal death investigation. Data analysis comprised univariate and bivariate descriptive statistical techniques; ecological analysis of incidence rates using population denominators; and comparison of age and sex of suicide cases to deaths from other causes using logistic regression.

Results

The study identified 141 suicides among nursing home residents, occurring at a rate of 0.02 deaths per 100 000 resident bed days. The ratio of deaths from suicide to deaths from any other cause was higher in males than females (OR = 3.56, 95%CI = 2.48–5.12, P = <0.001). Over half of the residents who died from suicide had a diagnosis of depression (n = 93, 66.0%) and had resided in the nursing home for less than 12 months (n = 71, 50.3%). Common major life stressors identified in suicide cases included the following: health deterioration (n = 112, 79.4%); isolation and loneliness (n = 60, 42.6%); and maladjustment to nursing home life (n = 42, 29.8%).

Conclusions

This research provides a foundational understanding of suicide among nursing home residents in Australia and contributes important new information to the international knowledge base.
Hand gestures support word learning in patients with hippocampal amnesia
Authors: Hilverman Caitlin , Cook Susan Wagner , Duff Melissa C.
Published: March 2018

Co‐speech hand gesture facilitates learning and memory, yet the cognitive and neural mechanisms supporting this remain unclear. One possibility is that motor information in gesture may engage procedural memory representations. Alternatively, iconic information from gesture may contribute to declarative memory representations mediated by the hippocampus. To investigate these alternatives, we examined gesture's effects on word learning in patients with hippocampal damage and declarative memory impairment, with intact procedural memory, and in healthy and in brain‐damaged comparison groups. Participants learned novel label‐object pairings while producing gesture, observing gesture, or observing without gesture. After a delay, recall and object identification were assessed. Unsurprisingly, amnesic patients were unable to recall the labels at test. However, they correctly identified objects at above chance levels, but only if they produced a gesture at encoding. Comparison groups performed well above chance at both recall and object identification regardless of gesture. These findings suggest that gesture production may support word learning by engaging nondeclarative (procedural) memory.
Fatigue resistance, electrochemical corrosion and biological response of Ti‐15Mo with surface modified by amorphous TiO2 nanotubes layer
Authors: Campanelli Leonardo C. , Oliveira Nilson T. C. , da Silva Paulo Sergio C. P. , Bolfarini Claudemiro , Palmieri Annalisa , Cura Francesca , Carinci Francesco , Motheo Artur J.
Published: March 2018

The objective of this work was a systemic evaluation of the anodizing treatment in a β‐type Ti‐15Mo alloy to grow a TiO2 nanostructured layer for osseointegration improvement. The technical viability of the surface modification was assessed based on the resistance to mechanical fatigue, electrochemical corrosion, and biological response. By using an organic solution of NH4F in ethylene glycol, a well‐organized array of 90 nm diameter nanotubes was obtained with a potential of 40 V for 6 h, while undefined nanotubes of 25 nm diameter were formed with a potential of 20 V for 1 h. Nevertheless, the production of the 90 nm diameter nanotubes was followed by micrometer pits that significantly reduced the fatigue performance. The undefined nanotubes of 25 nm diameter, besides the greater cell viability and improved osteoblastic cell differentiation in comparison to the as‐polished surface, were not deleterious to the fatigue and corrosion properties. This result strengthens the necessity of an overall evaluation of the anodizing treatment, particularly the fatigue resistance, before suggesting it for the design of implants. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 107B: 86–96, 2019.
Silk fibroin produced by transgenic silkworms overexpressing the Arg‐Gly‐Asp motif accelerates cutaneous wound healing in mice
Authors: Baba Atsunori , Matsushita Shigeto , Kitayama Kasumi , Asakura Tetsuo , Sezutsu Hideki , Tanimoto Akihide , Kanekura Takuro
Published: March 2018

We investigated the effect of silk fibroin (SF) on wound healing in mice. SF or an amorphous SF film (ASFF) prepared from silk produced by the wild‐type silkworm Bombyx mori (WT‐SF, WT‐ASFF) or by transgenic worms that overexpress the Arg‐Gly‐Asp (RGD) sequence (TG‐SF, TG‐ASFF) was placed on 5‐mm diameter full‐thickness skin wounds made by biopsy punch on the back of 8–12 week‐old BALB/c mice. Each wound was covered with WT‐ASFF and urethane film (UF), TG‐ASFF plus UF, or UF alone (control). Wound closure, histological thickness, the area of granulation tissue, and neovascularization were analyzed 4, 8, and 12 days later. The effect of SF on cell migration and proliferation was examined in vitro by scratch‐ and MTT‐assay using human dermal fibroblasts. Wound closure was prompted by TG‐ASFF, granulation tissue was thicker and larger in ASFF‐treated wounds than the control, and neovascularization was promoted significantly by WT‐ASFF. Both assays showed that SF induced the migration and proliferation of human dermal fibroblasts. The effects of TG‐ASFF and TG‐SF on wound closure, granulation formation, and cell proliferation were more profound than that of WT‐ASFF and WT‐SF. We document that SF accelerates cutaneous wound healing, and this effect is enhanced with TG‐SF. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 107B: 97–103, 2019.
Evaluating Potential QT Effects of JNJ‐54861911, a BACE Inhibitor in Single‐ and Multiple‐Ascending Dose Studies, and a Thorough QT Trial With Additional Retrospective Confirmation, Using Concentration‐QTc Analysis
Authors: Timmers Maarten , Sinha Vikash , Darpo Borje , Smith Brian , Brown Randy , Xue Hongqi , Ferber Georg , Streffer Johannes , Russu Alberto , Tritsmans Luc , Solanki Bhavna , Bogert Jennifer , Van Nueten Luc , Salvadore Giacomo , Nandy Partha
Published: March 2018

Nonclinical assays with JNJ‐54861911, a β‐secretase 1 inhibitor have indicated that at high concentrations, it may delay cardiac repolarization. A 4‐way crossover thorough QT (TQT) study was performed in 64 healthy subjects with 50 and 150 mg JNJ‐54861911 once daily for 7 days, placebo, and 400 mg moxifloxacin. Retrospective high‐precision QT (HPQT) analysis was performed on serial elecrocardiograms extracted from first‐in‐human single‐ascending dose (SAD) and multiple‐ascending dose (MAD) studies to evaluate if early studies could detect and predict QT effect. In the TQT study, a high therapeutic 50 mg dose did not cause QT prolongation, and an effect >10 milliseconds could be excluded at all postdose timepoints. QT prolongation with peak effect on placebo‐corrected change from baseline QTcF of 15.5 milliseconds (90%CI, 12.9‐18.1 milliseconds) was observed following a supratherapeutic dose (150 mg). No clinically relevant QT changes were observed in earlier studies. However, with SAD/MAD findings by HPQT, the slope of the exposure–response (ER) relationship in the SAD study (doses up to 150 mg) was similar to the TQT study slope, and the estimated QT effect was comparable at high plasma levels. In the MAD study, doses up to 90 mg once daily for 7 days resulted in JNJ‐54861911 peak plasma concentrations (Cmax) comparable to those in the SAD study (∼750 ng/mL), but ER by HPQT failed to detect a QT effect and resulted in negative estimations. Adding a higher dose cohort (150 mg; Cmax, 1125 ng/mL) demonstrated a QT effect, with a slightly lower ER slope than the TQT study. JNJ‐54861911 (up to 50 mg) did not cause QT prolongation at clinically relevant plasma concentrations in any studies. Provided sufficiently high plasma concentrations were captured, mild QT prolongation observed postdose with a supratherapeutic dose could be detected (TQT study) and estimated in SAD/MAD studies. Based on population pharmacokinetic modeling and simulation, 5 and 25 mg doses are currently considered for further phase 3 studies and are expected not to cause any relevant QT prolongation.
Disease–Drug Interactions in Inflammatory States via Effects on CYP‐Mediated Drug Clearance
Authors: Coutant David E. , Hall Stephen D.
Published: March 2018

The human inflammatory response can result in the alteration of drug clearance through effects on drug‐metabolizing enzymes or drug transporters. In this article, clinical examples are reviewed of how diseases with moderate to severe inflammation can decrease cytochrome P450 (CYP)–mediated drug clearance and alter plasma protein binding. Also examined is how albumin, α‐1‐acid glycoprotein, drug fraction unbound in plasma, CYP content, and oral clearance can change dynamically with time in response to inflammation.
Lack of interruption of the gene network underlying wing polyphenism in an early‐branching ant genus
Authors: Béhague Julien , Fisher Brian L. , Péronnet Romain , Rajakumar Rajendhran , Abouheif Ehab , Molet Mathieu
Published: March 2018

Ants evolved about 140 million years ago and have diversified into more than 15,000 species with tremendous ecological and morphological diversity, yet evolution of the gene regulatory networks (GRNs) underlying this diversification remains poorly understood. Wing polyphenism, the ability of a single genome to produce either winged or wingless castes during development in response to environmental cues, is a nearly universal feature of ants. The underlying wing GRN is evolutionarily labile in worker castes of phylogenetically derived species: it is conserved in winged castes but interrupted at different points in wingless castes of different species. However, it remains unknown whether the wing GRN is interrupted in wingless castes of species from early branching lineages, and if so, whether it is interrupted at similar locations in worker castes of derived species. We therefore used in situ hybridization to assay the expression of nine genes in the wing GRN in wing imaginal discs of larvae from two species from the early branching (‘basal’) genus Mystrium. These species possess two castes each: Mystrium rogeri has winged queens and wingless workers, and M. oberthueri has wingless queens and wingless workers. In contrast to derived species, we found no evidence of interruption points in the wing GRN kernel of wingless castes. Our finding supports: (1) a “phylogenetic ladder model” of wing GRN evolution, where interruption points move further upstream in the wing GRN as ant lineages become more derived; and (2) that evolutionary lability of the GRN underlying wing polyphenism originated later during ant evolution.