bluuebunny/crossref_metadata_2025 huggingface dataset:
Phylogenetic Analyses and Morphological Innovations in Land Plants
Authors: Doyle James A.
Published: May 2017

An increasingly robust phylogenetic framework based on molecular and fossil data clarifies the sequence of evolutionary innovations in land plants. Oogamy and cellular novelties (phragmoplast, plasmodesmata, incipient meristems) evolved in aquatic streptophytes. Invasion of the land entailed interpolation of the sporophyte, jacketed gametangia and sporangia, and air‐dispersed spores, followed by stomata. Origin of vascular plants involved branching of the sporophyte and stepwise evolution of vascular tissue. Leaves originated independently in lycophytes and euphyllophytes; in some euphyllophytes leaves were derived from single dichotomous branches, in others from whole branch systems. In seed plants, secondary growth evolved before the seed. Pinnately compound leaves were replaced by simple leaves in coniferophytes. The origin of the angiosperm flower remains unresolved, but bitegmic ovules may be derived from cupules, and the ancestral carpel can be reconstructed as ascidiate. Evolution of double fertilization was a stepwise process that continued within angiosperms; vessels also evolved within the group. Monocots show major reorganization tied to loss of secondary growth, while pentamerous flowers evolved from dimerous within eudicots.
Comparative Evolutionary Genomics of Land Plants
Authors: Litt Amy
Published: May 2017

The evolution of land plants is characterized by increasing adaptation to the terrestrial environment and increasing structural complexity. Flowering plants have more elaborate structure and life cycles than do mosses, and have diversified and colonized a wider variety of habitats. Nonetheless, analyses suggest that on average flowering plants have neither larger genomes nor more genes than mosses. Genome size varies dramatically among embryophytes but the most significant factor appears to be amplification of transposable elements, which not only mediate genome size but dynamically affect genome structure and function as well. Along with whole genome duplications and lineage‐specific expansion of individual gene families, they are responsible for shaping land plant genomes, generating substantial differences in genome size, gene number, and gene order even among closely related cultivars. Comparative analyses of fully sequenced genomes have shed substantial light on the dynamics of genome and gene family evolution; they are just beginning, however, to help us understand the molecular basis of the key adaptations that have allowed plants to thrive on land.
Development and the Evolution of Plant Form
Authors: Ambrose Barbara A. , Ferrándiz Cristina
Published: May 2017

Development in land plants is the process whereby a single cell becomes a large multicellular organism. Developmental networks specify every organ, tissue, or cell type from egg to juvenile to a reproducing adult. Therefore, it would follow that changes in developmental networks result in changes in form, and understanding these developmental networks and their changes would provide great insight into the evolution of plant form. Only recently has the field of evolutionary developmental biology (evo‐devo) been recognized as an important evolutionary mechanism; however, this field is still in its nascent stages in plants. Much of the plant evo‐devo studies have focused on the flower and to some extent on the leaf. However, to understand the evolution of plant form, these ideas and studies need to be extended across the land plants. We review what we know about the contribution of development to the evolution of plant form and discuss avenues of future research.
Development in the Wild: Phenotypic Plasticity
Authors: Donohue Kathleen
Published: May 2017

Development of organisms in the wild occurs in ecologically variable environments. Phenotypic plasticity occurs when a single genotype alters its phenotype in response to its environment. Some traits are more plastic than others, and whether a particular trait evolves plasticity depends on the degree of environmental variation experienced by that trait, the quality of environment‐dependent natural selection on that trait, and the strength of genetic correlations between the trait expressed in different environments. Thus, identifying the molecular basis of pleiotropy of traits expressed in different environments should be an important agenda in studies of development and plasticity. The strength of pleiotropy across environments can be influenced by environment‐dependent gene expression and signal transduction and by the structure of genetic pathways. The degree of environmental dependence of many of these molecular processes, however, is only beginning to be elucidated. Phenotypic plasticity influences adaptation, niche breadth, and ecological ranges and has the potential to influence the evolution of reproductive isolation. Understanding the genetic and ecological mechanisms of plasticity, therefore, will enhance our knowledge of the genetic basis of adaptation and the evolution of diversity.
The Evolution of Plant Form: A Summary Perspective
Authors: Purugganan Michael
Published: May 2017

The study of the evolution of development (evo‐devo) has advanced dramatically in the last two decades. Although there had been a strong interest in evo‐devo for nearly a century, it was only with the advent of molecular developmental genetics that provided a strong basis for a conceptual and methodological integration of developmental studies with evolutionary biology. The study of plant evolution of development has also progressed in the last two decades beginning with the study of the molecular basis for floral diversification in the angiosperms. The confluence of studies in development, molecular genetics, phylogenetics, paleobotany, population genetics, and molecular evolution in the study of plant form is now a robust discipline, with various opportunities to further our understanding of plant morphological evolution at all levels of biological organization.
Introduction: Mysteries, Molecules and Mechanisms
Authors: Bryant John A.
Published: May 2017

This brief chapter mentions the main structural and functional features of plant nuclei and in doing so, provides a very general introduction to other chapters in the book. It also covers aspects that are not featured elsewhere, especially the replication of nuclear DNA and the import of the replication proteins. Throughout the chapter there is an underlying theme of evolution, relating both to the similarities to and differences from the Archaea and to the possible evolutionary origins of the nucleus.
The Nuclear Envelope – Structure and Protein Interactions
Authors: Graumann Katja , Evans David E.
Published: May 2017

The proteins of the nuclear envelope have been characteriszd in detail in non‐plant systems, revealing a complex series of interactions between the inner and outer nuclear envelope, with the proteins of the nuclear pore complex and connecting to the nucleoskeleton and cytoskeleton. Many of the proteins described in animal and fungal systems have not been identified in plants; however, recent advances have resulted in the description of several key plant nuclear envelope proteins including members of the Sad1/UNC84 (SUN) domain family and recently the first Klarsicht/Anc‐1/Syne‐1 Homology (KASH)‐domain protein. This chapter describes the emerging networks of protein interactions at the plant nuclear envelope, together with discussion of their likely functions. In particular, the important role of plant SUN domain proteins as a key component of a linker of nucleoskeleton and cytoskeleton complex is described together with prospects for future study of plant nuclear envelope interaction networks.
The Plant Nuclear Pore Complex – The Nucleocytoplasmic Barrier and Beyond
Authors: Zhou Xiao , Boruc Joanna , Meier Iris
Published: May 2017

The nuclear pore complex (NPC) provides a highly organized pathway for selective transport between the nucleoplasm and the cytoplasm. Recent work undertaken to characterize the mechanisms and regulation of transport through the plant NPC has resulted in the identification of key components showing similarities – and also significant differences – between plants and other organisms. Mutant studies reveal roles for nucleoporins in plant–microbe interactions, hormone response, abiotic‐stress tolerance, plant development, and flowering‐time regulation. Recently, significant progress has been made in identifying about 30 proteins that constitute the plant NPC as well as several NPC‐associated proteins and in characterizing the structure of the plant NPC. A newly discovered connection between nuclear pore‐associated proteins and inner nuclear envelope proteins expands our knowledge of plant nuclear envelope architecture. Dynamic patterns of subcellular localization suggest mitotic functions of plant nucleoporins away from the nuclear pore.
Genomics and Chromatin Packaging
Authors: Sanchez‐Moran Eugenio
Published: May 2017

The role of DNA is to store an individual's genetic information so that it can be used during development and can be copied accurately during the divisions of the cell. DNA has to be packed within a small nucleus in an organized manner to be accessible for a variety of vital cell processes (transcription, DNA replication, repair, mitosis and meiosis). This is achieved by DNA associating with different proteins to form chromatin.

Different levels of compaction are involved, from the nucleosome fibre to higher order chromatin structures. All the chromatin components involved at different levels of DNA compaction are highly dynamic, allowing the required accessibility.

The understanding of chromatin components, their dynamics and interactions in plants would allow us to provide plant breeders with new tools to help fulfil the increased demand for food that will be required in future decades of increased global population and climate change.
Heterochromatin Positioning and Nuclear Architecture
Authors: Vanrobays Emmanuel , Thomas Mélanie , Tatout Christophe
Published: May 2017

Heitz (1928) first described the two states of chromatin known aseuchromatinandheterochromatin. Heterochromatin is often described as the gene‐poor part of the genome associated with a silent and condensed state of chromatin inaccessible to transcription factors. However, this simple view has been challenged many times as heterochromatin is indeed transcribed and differences between the two states of chromatin depend on many other criteria. Data collected from the model speciesArabidopsis thalianaindicate that heterochromatin relies on the repetitiveness of specific DNA sequences such as satellites, transposable elements and ribosomal DNA (rDNA) but also on epigenetic marks specifically associated with these repeated arrays. Recent studies on small RNA pathways have highlighted the central role of the RNA‐directed DNA methylation pathway in heterochromatin specification indicating that heterochromatin is indeed an epigenetic state required for many other genome functions including chromosome segregation, gene regulation or maintenance of genome stability. Heterochromatin is a specific feature of eukaryotes and preferential localization at the nuclear periphery and to the nucleolus is observed in most organisms. This spatial organization of heterochromatin is maintained through the cell cycle although DNA is replicated, chromatin is condensed into chromosomes, and the nuclear envelope is disrupted and reformed. Whether spatial positioning participates in heterochromatin function and how plant cells are able to establish and maintain such a genome organization across the cell cycle is still largely unknown inArabidopsis. Mechanisms leading to the appropriate positioning of heterochromatin within the nucleus will be discussed in the light of data coming from other species. A better understanding of heterochromatin organization and functions will be an important field of investigation for plants such as maize and wheat with considerably larger genome sizes thanArabidopsis.
Telomeres in Plant Meiosis: Their Structure, Dynamics and Function
Authors: Roberts Nicola Y. , Osman Kim , Franklin F. Chris H. , Pradillo Monica , Varas Javier , Santos Juan L. , Armstrong Susan J.
Published: May 2017

Although the primary role of the telomeres is to protect the chromosome ends from being recognized and processed as DNA double‐strand breaks, evidence is emerging that they have a pivotal role in early events in the movement and synapsis of homologous chromosomes in the meiotic pathway. Attention has been paid to the bouquet, a nearly universal event, during which the telomeres cluster on the nuclear envelope (NE) in early prophase I. It has been suggested that their close proximity promotes homologous pairing. We have previously shown in wild‐typeArabidopsis thalianathat the telomeres are organized around the nucleolus in somatic cells and during the early stages of meiosis. While still associated with the nucleolus, homologous telomeres undergo pairing at the transition from G2 to leptotene at around the same time as assembly of the axial elements. We do not observe a classical bouquet, but as the homologues synapse during zygotene, the paired telomeres occasionally reveal a loose clustering on the NE, which may represent a transient bouquet. As Arabidopsis homologous telomere pairing precedes transient bouquet formation, we have suggested that close juxtaposition of the homologues by virtue of the tethering of the paired telomeres to the NE may facilitate subsequent chromosome alignment and synapsis. Identifying proteins that link the telomeres and the NE has been stimulated by observations inSchizosaccharomyces pombe, where meiotic telomere clustering at the spindle polar body (SPB) involves Sad1, a SPB protein that is indirectly connected to a telomere binding protein, Rap1. Sad1 and the related protein UNC‐84 fromCaenorhabditis eleganscontain a so‐called SUN domain consisting of conserved C‐terminal protein regions a few hundred amino acids long. SUN domains are usually found following a transmembrane domain and a less conserved region of amino acids. Similar proteins have subsequently been identified in other yeasts and mammalian species. In the mouse and C.elegans, they appear to be required for telomere attachment to the NE and for moving the chromosomes via the telomeres in meiosis. Several components of the NE of plants have only recently been identified. This review focuses on the structure of the telomeres in Arabidopsis and their behaviour in the meiotic pathway. We also discuss recent observations linking a role for the meiotic telomeres and their association with the NE in meiotic prophase I.
Impact of Slurry Composition on Properties of Cellular Alumina: A Computed Tomographic Study
Authors: Betke Ulf , Dalicho Sebastian , Rannabauer Stefan , Lieb Alexandra , Scheffler Franziska , Scheffler Michael
Published: May 2017

Fine‐pored, 45 ppi (pores per linear inch) alumina foams are prepared from ceramic slurries with varying contents of additives (deflocculant, binder) and solid loading following a standardized procedure. Rheological key parameters (yield stress, high‐shear viscosity) of the respective slurries are determined by approximation of the experimental flow curves with appropriate rheological models. The resulting ceramic foams are characterized by computed tomography (CT) followed by a morphometric analysis of the reconstruction volume data. The main scope of the work involves the development of a procedure to reliably define the binarization threshold during these morphometric calculations, which is based on the analysis of the differential course of the total porosity results from calculations performed at varying binarization threshold values (“differential thresholding”). A very good match of the CT porosity results with experimental data is achieved, despite the unfavorable CT voxel resolution to foam structure fineness relation. The CT evaluation results are finally correlated to the rheological properties of the respective slurries used in foam manufacturing. The dominant slurry composition parameters are the weight fraction of the ceramic powder and the binder concentration. Increasing binder and solid content result in an increased yield stress and viscosity of the respective dispersion and consequently in a decreased porosity and cell size of the finally manufactured cellular ceramic.
A Single‐Molecular AND Gate Operated with Two Orthogonal Switching Mechanisms
Authors: Zhang Na , Lo Wai‐Yip , Jose Anex , Cai Zhengxu , Li Lianwei , Yu Luping
Published: May 2017

Single‐molecular electronics is a potential solution to nanoscale electronic devices. While simple functional single‐molecule devices such as diodes, switches, and wires are well studied, complex single‐molecular systems with multiple functional units are rarely investigated. Here, a single‐molecule AND logic gate is constructed from a proton‐switchable edge‐on gated pyridinoparacyclophane unit with a light‐switchable diarylethene unit. The AND gate can be controlled orthogonally by light and protonation and produce desired electrical output at room temperature. The AND gate shows high conductivity when treated with UV light and in the neutral state, and low conductivity when treated either with visible light or acid. A conductance difference of 7.3 is observed for the switching from the highest conducting state to second‐highest conducting state and a conductance ratio of 94 is observed between the most and least conducting states. The orthogonality of the two stimuli is further demonstrated by UV–vis, NMR, and density function theory calculations. This is a demonstration of concept of constructing a complex single‐molecule electronic device from two coupled functional units.
Remote Droplet Manipulation on Self‐Healing Thermally Activated Magnetic Slippery Surfaces
Authors: Irajizad Peyman , Ray Sahil , Farokhnia Nazanin , Hasnain Munib , Baldelli Steven , Ghasemi Hadi
Published: May 2017

Manipulation of discrete droplets is a paramount procedure in a broad spectrum of disciplines from digital microfluidics to energy and water systems. In these applications, droplet manipulation is required for mass or energy transport in various physical and chemical interactions. The discrete droplet manipulation enables developments of integrated microfluidic platforms without the use of conventional pumps, valves, or channels. A variety of approaches are developed for droplet manipulation. In these approaches, either the solid surface characteristics or droplet properties are tuned to control the droplet motion. However, drawbacks such as custom fabrication of the solid surface (e.g., embodiment of actuators in the solid and physical or chemical modification), limited application for high viscous fluids, fixed functionalities, and enhanced friction by the solid substrate have impeded their widespread implementation. Here, a new self‐healing surface called magnetic slippery surface (MAGSS) is reported for remote and controlled droplet manipulation with exceptional droplet mobility and a wide range of functionalities (e.g., transportation, guidance, removal, and merging of droplets). This surface allows droplet manipulation in a channel‐free configuration independent of viscosity of the droplet. This study envisions that MAGSS emerges as a disruptive platform for energy systems (e.g., condensation), miniature reactors, microfluidics devices, and medical bioassays.
Liquid–Liquid Interfacial Imaging Using Atomic Force Microscopy
Authors: Costa Luca , Li‐Destri Giovanni , Pontoni Diego , Konovalov Oleg , Thomson Neil H.
Published: May 2017

Nanoscale imaging of a liquid/liquid interface by atomic force microscopy (AFM) is achieved through the self‐assembly of interfacial layers of either polymers, lipids, or nanoparticles. Stabilization of the interface through spreading of a thin film of polystyrene‐b‐poly(methyl‐methacrylate) block copolymer or 1,2‐dioleoyl‐sn‐glycero‐3‐phosphoethanolamine lipids or adsorption of monolayers of silica nanoparticles allows reproducible imaging of these soft materials at an oil/water interface with nanoscale resolution on a timescale of 10 s. Amplitude modulation AFM is employed and requires that the subphase of water is below a critical depth of 100 µm to prevent excitation of gravity waves at the interface. The amplitude of these vertical oscillations is of the order of 1 nm but increases with the water layer depth. Below this critical water layer depth, force measurements show a linear compliance of the water/heptane and water/octane interfaces to be close to 10−2 N m−1. This study discusses in detail the experimental setup, sample preparation procedures, and AFM parameters necessary to achieve nanoscale resolution at the extremely soft and dynamic liquid interface. This expands the application of AFM to structural and dynamic nanoscale measurements for soft matter, biological, and nanomaterials away from solid supports.
Rapid Fabrication of Flexible and Stretchable Strain Sensor by Chitosan‐Based Water Ink for Plants Growth Monitoring
Authors: Tang Wenzhi , Yan Tingting , Ping Jianfeng , Wu Jian , Ying Yibin
Published: May 2017

Rapid fabrication of flexible and stretchable sensors is essential for the emerging applications of wearable devices. In this study, a chitosan‐based water ink realizes fabrication of flexible and stretchable stain sensor by simply writing the ink and leaving it to dry for ≈15 min at room temperature. It is found that chitosan is an excellent binding material. The fabricated sensor shows an excellent gauge factor of 64 within strain 1%–8%, and can be stretched up to 60%. More importantly, the sensor can be directly written on the subject, and sensors written on plants show that plants can response to mechanical injuries within a few minutes. These results show that this method reduces the energy and time consumption in the fabrication procedure, realizes direct fabrication of sensors on subjects for wearable monitoring, and meets the requirements for personalized and on‐site applications. So, this chitosan‐based ink provides an attractive strategy for the fabrication and application of wearable devices.
Hydrogenated TiO2 Thin Film for Accelerating Electron Transport in Highly Efficient Planar Perovskite Solar Cells
Authors: Yao Xin , Liang Junhui , Li Yuelong , Luo Jingshan , Shi Biao , Wei Changchun , Zhang Dekun , Li Baozhang , Ding Yi , Zhao Ying , Zhang Xiaodan
Published: May 2017

Intensive studies on low‐temperature deposited electron transport materials have been performed to improve the efficiency of n‐i‐p type planar perovskite solar cells to extend their application on plastic and multijunction device architectures. Here, a TiO2 film with enhanced conductivity and tailored band edge is prepared by magnetron sputtering at room temperature by hydrogen doping (HTO), which accelerates the electron extraction from perovskite photoabsorber and reduces charge transfer resistance, resulting in an improved short circuit current density and fill factor. The HTO film with upward shifted Fermi level guarantees a smaller loss on VOC and facilitates the growth of high‐quality absorber with much larger grains and more uniform size, leading to devices with negligible hysteresis. In comparison with the pristine TiO2 prepared without hydrogen doping, the HTO‐based device exhibits a substantial performance enhancement leading to an efficiency of 19.30% and more stabilized photovoltaic performance maintaining 93% of its initial value after 300 min continuous illumination in the glove box. These properties permit the room‐temperature magnetron sputtered HTO film as a promising electron transport material for flexible and tandem perovskite solar cell in the future.
Gambling with life: Masculinity, risk, and danger in the lives of unauthorized migrant roofers
Authors: Chávez Sergio , Altman Claire E.
Published: May 2017

Background

This paper examines the occupational experiences of unauthorized immigrants employed in one of the most dangerous occupations in the United States: roofing.

Methods

We draw on 40 in‐depth interviews with return migrants in Guanajuato, Mexico, to examine how the adoption of masculinity, dangerous working conditions, the labor market structure, and absence of legal status exacerbates injuries for unauthorized roofers.

Findings

Undocumented men return to Mexico injured with chronic pain, health complications, and trauma. We find that men “do gender” that is adopt masculine beliefs, when they skirt safety practices, police each other's behaviors, withhold their emotions, experience heightened stress, and engage in poor health behaviors. It is a combination of dangerous working conditions, economic insecurity, and men seeking to fulfill their masculine roles that all combine to create unsafe working conditions and lead to injuries.
Securinega Alkaloids: Complex Structures, Potent Bioactivities, and Efficient Total Syntheses
Authors: Wehlauch Robin , Gademann Karl
Published: May 2017

The Securinega alkaloids feature a compact tetracyclic structural framework and can be divided into four subclasses characterized by either a bridged [2.2.2]‐ or a [3.2.1]‐bicyclic core with two homologous series in each subclass. In the last two decades, many innovative strategies to chemically access the Securinega alkaloids have been developed. This Focus Review discusses the selected structures and syntheses of representative members of the Securinega alkaloids. Ring‐closing metathesis has enabled the syntheses of securinine and norsecurinine, and different cycloaddition approaches were key to the syntheses of nirurine and virosaines A and B. Virosine A was accessed through a Vilsmeier–Haack/Mannich reaction cascade. A bio‐inspired vinylogous Mannich reaction has enabled the synthesis of allosecurinine and this strategy has been extended by an intramolecular 1,6‐addition to obtain bubbialidine and secu′amamine E. A rearrangement process of the latter two alkaloids has furnished allonorsecurinine and allosecurinine, respectively. Finally, an expanded model for the biogenesis of the Securinega alkaloid subclasses is discussed.
Serum Neurofilament light: A biomarker of neuronal damage in multiple sclerosis
Authors: Disanto Giulio , Barro Christian , Benkert Pascal , Naegelin Yvonne , Schädelin Sabine , Giardiello Antonella , Zecca Chiara , Blennow Kaj , Zetterberg Henrik , Leppert David , Kappos Ludwig , Gobbi Claudio , Kuhle Jens ,   the Swiss Multiple Sclerosis Cohort Study Group
Published: May 2017

Objective

Neurofilament light chains (NfL) are unique to neuronal cells, are shed to the cerebrospinal fluid (CSF), and are detectable at low concentrations in peripheral blood. Various diseases causing neuronal damage have resulted in elevated CSF concentrations. We explored the value of an ultrasensitive single‐molecule array (Simoa) serum NfL (sNfL) assay in multiple sclerosis (MS).

Methods

sNfL levels were measured in healthy controls (HC, n = 254) and two independent MS cohorts: (1) cross‐sectional with paired serum and CSF samples (n = 142), and (2) longitudinal with repeated serum sampling (n = 246, median follow‐up = 3.1 years, interquartile range [IQR] = 2.0–4.0). We assessed their relation to concurrent clinical, imaging, and treatment parameters and to future clinical outcomes.

Results

sNfL levels were higher in both MS cohorts than in HC (p < 0.001). We found a strong association between CSF NfL and sNfL (β = 0.589, p < 0.001). Patients with either brain or spinal (43.4pg/ml, IQR = 25.2–65.3) or both brain and spinal gadolinium‐enhancing lesions (62.5pg/ml, IQR = 42.7–71.4) had higher sNfL than those without (29.6pg/ml, IQR = 20.9–41.8; β = 1.461, p = 0.005 and β = 1.902, p = 0.002, respectively). sNfL was independently associated with Expanded Disability Status Scale (EDSS) assessments (β = 1.105, p < 0.001) and presence of relapses (β = 1.430, p < 0.001). sNfL levels were lower under disease‐modifying treatment (β = 0.818, p = 0.003). Patients with sNfL levels above the 80th, 90th, 95th, 97.5th, and 99th HC‐based percentiles had higher risk of relapses (97.5th percentile: incidence rate ratio = 1.94, 95% confidence interval [CI] = 1.21–3.10, p = 0.006) and EDSS worsening (97.5th percentile: OR = 2.41, 95% CI = 1.07–5.42, p = 0.034).

Interpretation

These results support the value of sNfL as a sensitive and clinically meaningful blood biomarker to monitor tissue damage and the effects of therapies in MS. Ann Neurol 2017;81:857–870
Photoredox‐gesteuerte Mono‐ und Di‐Multifluorarylierung von C(sp3)‐H‐Bindungen mit Arylfluoriden
Authors: Xie Jin , Rudolph Matthias , Rominger Frank , Hashmi A. Stephen K.
Published: May 2017

Die kontrollierbare Mono‐ und Di‐Multifluorarylierung von acyclischen und cyclischen N‐Arylaminen mit Arylfluoriden über photokatalysierte duale C(sp3)‐H/C(sp2)‐F‐Funktionalisierung eröffnet einen neuen Zugang zu einem breiten Spektrum von wertvollen α‐fluorarylierten Aminen. Auch eine sequenzielle Eintopf‐Hetero‐Di‐Multifluorarylierung von N‐Arylpyrrolidinen und N,N‐Dimethylanilinen gelang mit hoher bis ausgezeichneter Diastereoselektivität. Diese neue defluorierende C(sp3)‐C(sp2)‐Kupplung zeichnet sich durch eine große Anwendungsbreite, gute Regioselektivität und milde Bedingungen und auch eine Anwendbarkeit im Gramm‐Maßstab und auf späten Synthesestufen aus. Sie stellt damit einen signifikanten Fortschritt in der Arylierung von nichtaktivierten C(sp3)‐H‐Bindungen mit Arylfluoriden dar.
Selbstassemblierende und selbstheilende Partikelfilme zur Überwindung der Instabilität nanopartikulärer Katalysatorfilme in der alkalischen Elektrolyse
Authors: Barwe Stefan , Masa Justus , Andronescu Corina , Mei Bastian , Schuhmann Wolfgang , Ventosa Edgar
Published: May 2017

Die Entwicklung stabiler Elektroden für die elektrochemische Wasserspaltung, insbesondere hinsichtlich der Elektrodenmodifizierung mittels Nanopartikeln, stellt immer noch eine große Herausforderung dar. Wir berichten über ein innovatives Verfahren zur Bildung hochstabiler Katalysatorfilme mit selbstheilenden Eigenschaften. Das Verfahren basiert auf sich während der Elektrolyse in situ selbstassemblierenden Nanopartikeln. Katalysatorpartikel werden zum Elektrolyten gegeben, sodass sich eine Suspension bildet, die durch die elektrochemische Zelle gepumpt wird. Partikel mit negativ geladener Oberfläche modifizieren dabei die Anode, während Partikel mit positiv geladener Oberfläche sich auf der Kathode abscheiden. Die so selbstassemblierten Katalysatorfilme weisen einen Selbstheilungseffekt auf, solange sich Katalysatorpartikel im Elektrolyt befinden. Die Funktion wurde mittels eines alkalischen Elektrolyseurs unter Verwendung von NiFe‐LDH und NixB für die Anoden‐ bzw. Kathodenseite durchgeführt. Stabile Zellspannungen konnten für Stromdichten von 50 bzw. 100 mA cm−2 über einen Zeitraum von mindestens drei Wochen beobachtet werden.
Implementation of Treat‐to‐Target in Rheumatoid Arthritis Through a Learning Collaborative: Results of a Randomized Controlled Trial
Authors: Solomon Daniel H. , Losina Elena , Lu Bing , Zak Agnes , Corrigan Cassandra , Lee Sara B. , Agosti Jenifer , Bitton Asaf , Harrold Leslie R. , Pincus Theodore , Radner Helga , Yu Zhi , Smolen Josef S. , Fraenkel Liana , Katz Jeffrey N.
Published: May 2017

Objective

Treat‐to‐target (TTT) is an accepted paradigm for the management of rheumatoid arthritis (RA), but some evidence suggests poor adherence. The purpose of this study was to test the effects of a group‐based multisite improvement learning collaborative on adherence to TTT.

Methods

We conducted a cluster‐randomized quality‐improvement trial with waitlist control across 11 rheumatology sites in the US. The intervention entailed a 9‐month group‐based learning collaborative that incorporated rapid‐cycle improvement methods. A composite TTT implementation score was calculated as the percentage of 4 required items documented in the visit notes for each patient at 2 time points, as evaluated by trained staff. The mean change in the implementation score for TTT across all patients for the intervention sites was compared with that for the control sites after accounting for intracluster correlation using linear mixed models.

Results

Five sites with a total of 23 participating rheumatology providers were randomized to intervention and 6 sites with 23 participating rheumatology providers were randomized to the waitlist control. The intervention included 320 patients, and the control included 321 patients. At baseline, the mean TTT implementation score was 11% in both arms; after the 9‐month intervention, the mean TTT implementation score was 57% in the intervention group and 25% in the control group (change in score of 46% for intervention and 14% for control; P = 0.004). We did not observe excessive use of resources or excessive occurrence of adverse events in the intervention arm.

Conclusion

A learning collaborative resulted in substantial improvements in adherence to TTT for the management of RA. This study supports the use of an educational collaborative to improve quality.
Role of Gut Inflammation in Altering the Monocyte Compartment and Its Osteoclastogenic Potential in HLA–B27–Transgenic Rats
Authors: Ansalone Cecilia , Utriainen Lotta , Milling Simon , Goodyear Carl S.
Published: May 2017

Objective

To investigate the relationship between intestinal inflammation and the central and peripheral innate immune system in the pathogenesis of HLA–B27–associated spondyloarthritis using an HLA–B27–transgenic (B27‐Tg) rat model.

Methods

The myeloid compartment of the blood and bone marrow (BM) of B27‐Tg rats, as well as HLA–B7–Tg and non‐Tg rats as controls, was evaluated by flow cytometry. Plasma from rats was assessed by enzyme‐linked immunosorbent assay for levels of CCL2 and interleukin‐1α (IL‐1α). Rats were treated with antibiotics for 4 weeks, and the myeloid compartment of the blood and BM was evaluated by flow cytometry. The osteoclastogenic potential of BM‐derived cells from antibiotic‐treated rats, in the presence or absence of tumor necrosis factor (TNF), was evaluated in vitro.

Results

B27‐Tg rats had substantially higher numbers of circulating Lin−CD172a+CD43low monocytes as compared to control animals, and this was significantly correlated with higher levels of plasma CCL2. Antibiotic treatment of B27‐Tg rats markedly reduced the severity of ileitis, plasma levels of CCL2 and IL‐1α, and number of BM and blood Lin−CD172a+CD43low monocytes, a cell subset shown in the present study to have the greatest in vitro osteoclastogenic potential. Antibiotic treatment also prevented the TNF‐dependent enhancement of osteoclastogenesis in B27‐Tg rats.

Conclusion

Microbiota‐dependent intestinal inflammation in B27‐Tg rats directly drives the systemic inflammatory and bone‐erosive potential of the monocyte compartment.
Influence of quercetin on the interaction of gliclazide with human serum albumin – spectroscopic and docking approaches
Authors: Kameníková Miroslava , Furtmüller Paul Georg , Klacsová Mária , Lopez‐Guzman Arturo , Toca‐Herrera José Luis , Vitkovská Anika , Devínsky Ferdinand , Mučaji Pavel , Nagy Milan
Published: May 2017

Protein‐binding interactions are displacement reactions which have been implicated as the causative mechanisms in many drug–drug interactions. Thus, the aim of presented study was to analyse human serum albumin‐binding displacement interaction between two ligands, hypoglycaemic drug gliclazide and widely distributed plant flavonoid quercetin. Fluorescence analysis was used in order to investigate the effect of substances on intrinsic fluorescence of human serum albumin (HSA) and to define binding and quenching properties of ligand–albumin complexes in binary and ternary systems, respectively. Both ligands showed the ability to bind to HSA, although to a different extent. The displacement effect of one ligand from HSA by the other one has been described on the basis of the quenching curves and binding constants comparison for the binary and ternary systems. According to the fluorescence data analysis, gliclazide presents a substance with a lower binding capacity towards HSA compared with quercetin. Results also showed that the presence of quercetin hindered the interaction between HSA and gliclazide, as the binding constant for gliclazide in the ternary system was remarkably lower compared with the binary system. This finding indicates a possibility for an increase in the non‐bound fraction of gliclazide which can lead to its more significant hypoglycaemic effect. Additionally, secondary and tertiary structure conformational alterations of HSA upon binding of both ligands were investigated using synchronous fluorescence, circular dichroism and FT‐IR. Experimental data were complemented with molecular docking studies. Obtained results provide beneficial information about possible interference upon simultaneous co‐administration of the food/dietary supplement and drug.
A porphyrin‐based fluorescence method for zinc determination in commercial propolis extracts without sample pretreatment
Authors: Pierini Gastón Darío , Pinto Victor Hugo A. , Maia Clarissa G.C. , Fragoso Wallace D. , Reboucas Julio S. , Centurión María Eugenia , Pistonesi Marcelo Fabián , Di Nezio María Susana
Published: May 2017

The quantification of zinc in over‐the–counter drugs as commercial propolis extracts by molecular fluorescence technique using meso‐tetrakis(4‐carboxyphenyl)porphyrin (H2TCPP4) was developed for the first time. The calibration curve is linear from 6.60 to 100 nmol L−1 of Zn2+. The detection and quantification limits were 6.22 nmol L−1 and 19.0 nmol L−1, respectively. The reproducibility and repeatability calculated as the percentage variation of slopes of seven calibration curves were 6.75% and 4.61%, respectively. Commercial propolis extract samples from four Brazilian states were analyzed and the results (0.329–0.797 mg/100 mL) obtained with this method are in good agreement with that obtained with the Atomic Absorption Spectroscopy (AAS) technique. The method is simple, fast, of low cost and allows the analysis of the samples without pretreatment. Moreover the major advantage is that Zn‐porphyrin complex presents fluorescent characteristic promoting the selectivity and sensitivity of the method.
Luminescence, circular dichroism and in silico studies of binding interaction of synthesized naphthylchalcone derivatives with bovine serum albumin
Authors: Pasricha Sharda , Sharma Deepti , Ojha Himanshu , Gahlot Pragya , Pathak Mallika , Basu Mitra , Chawla Raman , Singhal Sugandha , Singh Anju , Goel Rajeev , Kukreti Shrikant , Shukla Shefali
Published: May 2017

Chalcones possess various biological properties, for example, antimicrobial, anti‐inflammatory, analgesic, antimalarial, anticancer, antiprotozoal and antitubercular activity. In this study, naphthylchalcone derivatives were synthesized and characterized using 1H NMR 13C NMR, Fourier transform infrared and mass techniques. Yields for all derivatives were found to be >90%. Protein–drug interactions influence the absorption, distribution, metabolism and excretion (ADME) properties of a drug. Therefore, to establish whether the synthesized naphthylchalcone derivatives can be used as drugs, their binding interaction toward a serum protein (bovine serum albumin) was investigated using fluorescence, circular dichroism and molecular docking techniques under physiological conditions. Fluorescence quenching of the protein in the presence of naphthylchalcone derivatives, and other derived parameters such as association constants, number of binding sites and static quenching involving confirmed non‐covalent binding interactions in the protein–ligand complex were observed. Circular dichroism clearly showed changes in the secondary structure of the protein in the presence of naphthylchalcones, indicating binding between the derivatives and the serum protein. Molecular modelling further confirmed the binding mode of naphthylchalcone derivatives in bovine serum albumin. A site‐specific molecular docking study of naphthylchalcone derivatives with serum albumin showed that binding took place primarily in the aromatic low helix and then in subdomain II. The dominance of hydrophobic, hydrophilic and hydrogen bonding was clearly visible and was responsible for stabilization of the complex.
Fatigue and cognition: Pupillary responses to problem‐solving in early multiple sclerosis patients
Authors: de Rodez Benavent Sigrid A. , Nygaard Gro O. , Harbo Hanne F. , Tønnesen Siren , Sowa Piotr , Landrø Nils I. , Wendel‐Haga Marte , Etholm Lars , Nilsen Kristian B. , Drolsum Liv , Kerty Emilia , Celius Elisabeth G. , Laeng Bruno
Published: May 2017

Introduction

In early multiple sclerosis (MS) patients, cognitive changes and fatigue are frequent and troublesome symptoms, probably related to both structural and functional brain changes. Whether there is a common cause of these symptoms in MS is unknown. In theory, an altered regulation of central neuropeptides can lead to changes in regulation of autonomic function, cognitive difficulties, and fatigue. Direct measurements of central neuropeptides are difficult to perform, but measurements of the eye pupil can be used as a reliable proxy of function.

Methods

This study assesses pupil size during problem‐solving in early MS patients versus controls. A difference in pupil size to a cognitive challenge could signal altered activity within the autonomic system because of early functional brain changes associated with cognitive load. We recruited MS patients (mean disease duration: 2.6 years, N = 41) and age‐matched healthy controls (N = 43) without eye pathology. Neurological impairment, magnetic resonance imaging, visual evoked potentials, depression, and fatigue were assessed in all of the patients. In both groups, we assessed processing speed and retinal imaging. Pupil size was recorded with an eye‐tracker during playback of multiplication tasks.

Results

Both groups performed well on the cognitive test. The groups showed similar pupillary responses with a mean of 0.55 mm dilation in patients and 0.54 mm dilation in controls for all the tasks collapsed together. However, controls (N = 9) with low cognitive scores (LCS) had an increased pupillary response to cognitive tasks, whereas LCS MS patients (N = 6) did not (p < .05). There was a tendency toward a smaller pupillary response in patients with fatigue.

Conclusions

This is the first study to investigate pupillary responses to cognitive tasks in MS patients. Our results suggest that MS‐related changes in cognition and fatigue may be associated with changes in arousal and the autonomic regulation of task‐related pupillary responses. This supports the theory of a link between cognition and fatigue in MS.
Validity and reliability of the Finnish version of the Multiple Sclerosis Impact Scale‐29
Authors: Rosti‐Otajärvi Eija , Hämäläinen Päivi , Wiksten Anna , Hakkarainen Tanja , Ruutiainen Juhani
Published: May 2017

Background

The Multiple Sclerosis Impact Scale‐29 (MSIS‐29) has been increasingly used to evaluate the self‐perceived impact of multiple sclerosis (MS) on a patient.

Objectives

The aim of this study was to evaluate the psychometric properties of the Finnish version of MSIS‐29 in patients with MS.

Methods

A total of 553 patients with MS completed the MSIS‐29 and self‐administered questionnaires capturing information on demographics, disease characteristics and severity, perceived quality of life (EuroQol 5D‐3L instrument), and fatigue (Fatigue Severity Scale).

Results

The data quality for MSIS‐29 was excellent, with 99.5% computable scores for the MSIS‐29 physical scale and 99.3% for the MSIS‐29 psychological scale. Floor and ceiling effects were minimal. Excellent Cronbach's alpha values of 0.97 and 0.90 were seen for MSIS‐29 physical and psychological subscales, respectively. The physical subscale showed highest correlations with measures of physical functioning, such as disease severity and the mobility domain of the quality of life. Similarly, the psychological subscale showed highest correlations with self‐reported fatigue and the anxiety/depression domains of the quality of life. MSIS‐29 physical scores related strongly to disease severity, whereas the MSIS‐29 psychological scores increased in mild disease but declined in more severe disease forms.

Conclusion

The Finnish version of MSIS‐29 has satisfactory psychometric properties. Consistent with the previous recommendations, the use of two MSIS‐29 subscale scores instead of a total score was supported.
Free speech is only ‘free’ if it is truly free for all
Authors: Zacarese Lawrence M.
Published: May 2017

“Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the government for a redress of grievances.” This is the text of the First Amendment to the United States Constitution taken verbatim, sans any changes or extra language.
Late complications after Cabrol technique in a case with Marfan syndrome
Authors: Ohki Shin‐ichi , Takazawa Ippei , Akutsu Hirohiko , Misawa Yoshio
Published: May 2017

Key Clinical Message

A patient with Marfan syndrome underwent aortic root replacement with the Cabrol technique at 37 years of age. She underwent a surgical repair for an aneurysm in the right coronary at 58 years of age, followed by a surgical repair for a pseudoaneurysm of the left coronary artery at 64 years of age.
Forschungsstand und Normungsantrag zur Festigkeitsprüfung thermisch gebogener Gläser
Authors: Bukieda Paulina , Engelmann Michael , Elstner Michael , Weller Bernhard
Published: May 2017

Vorhandene Forschungsaktivitäten haben gezeigt, dass das grundsätzliche Vorgehen zur Biegezugfestigkeitsprüfung nach dem Vierschneiden‐Verfahren für Flachglas nach DIN EN 1288‐3 auf thermisch gebogenes Glas übertragbar ist. Jedoch liegt derzeit keine normativ verankerte Methode vor, bei dem aus der Bruchlast ohne den Einsatz kostenintensiver Dehnungsmessstreifen direkt auf die Bruchspannung geschlossen werden kann. Ein solches Verfahren wird mittels einer umfänglichen experimentellen und numerischen Studie im Forschungsprojekt PRÜFgbGLAS entwickelt. Der Stand des Gemeinschaftsprojektes des Bundesverbandes Flachglas e.V., des Fachverbandes Konstruktiver Glasbau e.V., des Institutes für Baukonstruktion der TU Dresden und vier Glasbiegereien wird in diesem Beitrag vorgestellt. Dabei werden die Grundlagen für die Prüfung zylindrisch gebogener Gläser mit beliebigem Biegeradius und Glasdicken von 3 mm bis 12 mm gelegt. Die Projektpartner haben bereits einen entsprechenden Normungsantrag beim Deutschen Institut für Normung e.V. gestellt und möchten die Fachwelt mit diesem Beitrag zur Diskussion einladen.
Kantenfestigkeit von Floatglas in Abhängigkeit von wesentlichen Schneidprozessparametern
Authors: Ensslen Frank , Müller‐Braun Steffen
Published: May 2017

Das Gros der Standard‐Isoliergläser weist geschnittene Kanten aus Floatglas auf, deren Festigkeit für die Bemessung, insbesondere von Dreifach‐Gläsern, zunehmend an Bedeutung gewinnt. DIN 1249‐11 definiert für die Kantenausführung rein visuelle Merkmale, die nicht zwangsläufig mit der Festigkeit korrelieren. Letztere wird zudem in Abhängigkeit von den Schneidparametern derzeit noch unzureichend betrachtet. Unter Federführung des Arbeitskreises “Kantenfestigkeit” beim Fachverband Konstruktiver Glasbau e.V. wurden verschieden hergestellte Schnittkanten untersucht. Die Ergebnisanalysen erlauben eine orientierende Abschätzung der Kantenfestigkeit von FloatglasSchnittkanten in Bezug auf den Einfluss von wesentlichen Prozessparametern.