bluuebunny/crossref_metadata_2025 huggingface dataset:
Glucosinolates
Authors: Jeschke Verena , Burow Meike
Published: June 2018

Plants resist herbivorous insects and pathogens by employing specialised metabolites as chemical defences. In the case of constitutively present activated defences, an inactive precursor is stored and activated upon damage or attack by biotic stressors releasing high amounts of toxic and bioactive products. Glucosinolates are a group of defence compounds found in cruciferous vegetables. They consist of a nitrogen‐ and sulfur‐containing core structure and an amino acid‐derived, variable side chain. Enzymatic activation of glucosinolates further amplifies their chemical diversity, as one glucosinolate can generate different bioactive metabolites. These serve diverse functions in plant–insect and plant–pathogen interactions. Insects, however, have evolved many creative adaptations to avoid toxic glucosinolate‐derived metabolites. For humans, glucosinolates and their activation products have many beneficial health effects and promising applications in sustainable agriculture.

Key Concepts

Plants of the Brassicales order store nontoxic glucosinolates as precursors of bioactive compounds to defend themselves against herbivores and pathogens.

Glucosinolate composition varies across and within plant species as well as between tissues, developmental stages and environmental conditions.

Upon attack, enzymatic activation of glucosinolates initiated by myrosinase enzymes further amplifies their structural diversity, which is pivotal for the plants' resistance against a wide range of biotic enemies.

Against harmful bacteria and fungi, activation of particularly indolic glucosinolates in intact plant tissue can also occur through atypical myrosinases.

Glucosinolate‐derived bioactive compounds function in both direct and indirect defence against insect herbivores.

Many herbivores have adapted towards feeding on glucosinolate‐containing plants and have developed creative counteradaptations against the glucosinolate–myrosinase system, while nonadapted herbivores rely on detoxification of glucosinolate‐derived active compounds.

Apart from their defensive functions, glucosinolates serve as molecular signal to feedback regulate plant metabolism, growth and defence.

The chemical diversity of glucosinolates and their hydrolysis products provides benefits for human health and promising applications for sustainable agriculture.
The Child in the Paediatric Genetics Clinic
Authors: McLaughlin Janice
Published: June 2018

Children with unexplained problems in their development can be referred to genetics clinics; the number having such referrals is increasing as new technologies enhance the number of genetic variations that can be identified. From the perspective of the child and their family, this raises a number of issues social science research can help us to understand. In particular, issues such as understandings of kinship; feelings of parental responsibility; the uncertainties involved in diagnosis and the different ways the child is visualised through the stages of diagnosis. As new‐generation sequencing enters the clinic, it is important to consider how what happens to children and their families may both change and stay the same.

Key Concepts

Kinship can have both social and biological meaning.

Parents seek a genetic diagnosis to resolve social as well as medical problems.

A diagnosis that does not provide an answer to what the future holds for a child, or how they should be cared for, may not be seen by parents as a diagnosis.

Geneticists deploy both interpretative and communicative skills in their interactions with children and their families.

As new‐generation sequencing (NGS) enters clinical practice, it will generate social and ethical issues.

A small number of studies of NGS in clinical practice indicate some continuity in the challenges of managing diagnostic uncertainty for both geneticists and families.
Brain Training
Authors: Pahor Anja , Jaeggi Susanne M , Seitz Aaron R
Published: June 2018

Brain training aims to enhance cognitive processes such as perception, motor control, memory and decision‐making. Emerging research demonstrates that such cognitive processes can be trained, leading to improvements in everyday functioning that depend on these processes. As such, brain training is a rich and exciting field that delves into the limits of the human brain and has potential to benefit everyone's lives. However, while brain training shows promise, it has also sparked controversy as results are mixed across studies, and because findings are often sensationalised with an increasing number of commercial brain‐training products. The field is active and evolving and has the potential to overcome these issues as research clarifies what techniques show the most promise and uncovers the ingredients that most consistently lead to real‐world benefits.

Key Concepts

Brain training aims at improving the function of one or more cognitive processes.

Cognitive processes include perceptual abilities, motor learning, memory and executive function.

Nearly all populations, healthy or impaired, could benefit from effective brain‐training interventions.

The ultimate goal of brain training is to generalise beyond the training context to benefit everyday functioning.

The evidence supporting effectiveness of brain training is mixed, and findings are actively debated.

Brain training is an interesting field that will likely improve in the future as research uncovers which techniques show most promise, and for whom.
Association Between Declining Walking Speed and Increasing Bone Marrow Lesion and Effusion Volume in Individuals with Accelerated Knee Osteoarthritis
Authors: Harkey Matthew S. , Price Lori Lyn , McAlindon Timothy E. , Davis Julie E. , Stout Alina C. , Lu Bing , Zhang Ming , Eaton Charles B. , Barbe Mary F. , Lo Grace H. , Driban Jeffrey B.
Published: June 2018

Objective

To determine whether a decline in walking speed during the year prior to disease onset is associated with concurrent changes in cartilage, bone marrow lesions (BMLs), or effusion in adults who develop common knee osteoarthritis (OA), accelerated knee OA, or no knee OA.

Methods

We identified 3 groups from the Osteoarthritis Initiative based on annual radiographs from baseline to 48 months: accelerated knee OA, common knee OA, and no knee OA. We used the cartilage damage index (CDI) to assess tibiofemoral cartilage damage and used a semiautomated program to measure BML and effusion volume. Walking speed was assessed as an individual's habitual walking speed over 20 meters. One‐year change in walking speed and structural measures were calculated as index visit measurements minus measurements from the year prior visit. Logistic regression models were used to determine whether change in walking speed (exposure) was associated with change in each structural measure (outcome) for the overall group and then separately for the accelerated knee OA, common knee OA, and no knee OA groups.

Results

Adults who slowed their walking speed were almost twice as likely to present with increased BML volume, with a significant association (odds ratio 3.04 [95% confidence interval (95% CI) 1.03–8.95]) among adults with accelerated knee OA. Adults with accelerated knee OA who slowed their walking speed were approximately 3.4 times (95% CI 1.10–10.49) more likely to present with increased effusion volume. Walking speed change was not significantly associated with CDI change.

Conclusion

A change in an easily assessable clinical examination (i.e., 20‐meter walk test) was associated with concurrent worsening in BML and effusion volume in adults who developed accelerated knee OA.
Impact of High‐Intensity Interval Training on Disease Activity and Disease in Patients With Psoriatic Arthritis: A Randomized Controlled Trial
Authors: Thomsen Ruth S. , Nilsen Tom I. L. , Haugeberg Glenn , Bye Anja , Kavanaugh Arthur , Hoff Mari
Published: June 2018

Objective

To evaluate the impact of high‐intensity interval training (HIIT) on disease activity and disease perception in patients with psoriatic arthritis (PsA) and to evaluate whether a potential effect could be sustained for a longer period of time.

Methods

We randomly assigned 67 patients with PsA (43 women and 24 men) to an intervention group in which patients performed HIIT for 11 weeks or a control group of patients who were instructed not to change their physical exercise habits. Outcomes were assessed at 3 months and 9 months with the patient's global assessment (PGA), fatigue, and pain scores measured on a 100‐mm visual analog scale (VAS), and the composite Disease Activity Score in 44 joints (DAS44) was calculated. We used linear mixed models to calculate the mean difference (95% confidence interval [95% CI]) between groups according to the intent‐to‐treat principle.

Results

At 3 months, there was no clear difference in the PGA score (–0.49 [95% CI –10.91, 9.94]), DAS44 (–0.08 [95% CI –0.36, 0.20]), or pain intensity (5.45 [95% CI –4.36, 15.26]) between the groups. However, patients in the intervention group reported less fatigue (–12.83 [95% CI –25.88, 0.23]) than those in the control group. There was no evidence of long‐term effects of HIIT on outcomes measured at 9 months.

Conclusion

HIIT showed no clear effects on disease activity markers in patients with PsA, but the intervention (exercise) group reported meaningfully less fatigue after the intervention period. The results of this study suggest that patients with PsA tolerate HIIT without deterioration of disease activity and with improvement in fatigue.
Microstructure and Processing of 3D Printed Tungsten Microlattices and Infiltrated W–Cu Composites
Authors: Calvo Micha , Jakus Adam E. , Shah Ramille N. , Spolenak Ralph , Dunand David C.
Published: June 2018

Tungsten is of industrial relevance due its outstanding intrinsic properties (e.g., highest melting‐point of all elements) and therefore difficult to 3D‐print by conventional methods. Here, tungsten micro‐lattices are produced by room‐temperature extrusion‐based 3D‐printing of an ink comprising WO3–0.5%NiO submicron powders, followed by H2‐reduction and Ni‐activated sintering. The green bodies underwent isotropic linear shrinkage of ≈50% during the thermal treatment resulting in micro‐lattices, with overall 35–60% open‐porosity, consisting of 95–100% dense W–0.5%Ni struts having ≈80–300 μm diameter. Ball‐milling the powders and inks reduced the sintering temperature needed to achieve full densification from 1400 to 1200 °C and enabled the ink to be extruded through finer nozzles (200 μm). Partial sintering of the struts is achieved when NiO is omitted from the ink, with submicron interconnected‐porosity of ≈34%. Several tungsten micro‐lattices are infiltrated with molten copper at 1300 °C under vacuum, resulting in dense, anisotropic W–Cu composites with 40–65% tungsten volume fraction. Partially sintered struts (containing nickel) with submicron open porosity are also infiltrated with Cu, resulting in co‐continuous W–Cu composites with wide W struts/Cu channels at the lattice scale (hundreds of micrometers), and fine W–Cu interpenetrating network at the strut scale (hundreds of nanometers) allowing for the design of anisotropic mechanical and electrical properties.
High‐Brightness Blue Light‐Emitting Diodes Enabled by a Directly Grown Graphene Buffer Layer
Authors: Chen Zhaolong , Zhang Xiang , Dou Zhipeng , Wei Tongbo , Liu Zhiqiang , Qi Yue , Ci Haina , Wang Yunyu , Li Yang , Chang Hongliang , Yan Jianchang , Yang Shenyuan , Zhang Yanfeng , Wang Junxi , Gao Peng , Li Jinmin , Liu Zhongfan
Published: June 2018

Single‐crystalline GaN‐based light‐emitting diodes (LEDs) with high efficiency and long lifetime are the most promising solid‐state lighting source compared with conventional incandescent and fluorescent lamps. However, the lattice and thermal mismatch between GaN and sapphire substrate always induces high stress and high density of dislocations and thus degrades the performance of LEDs. Here, the growth of high‐quality GaN with low stress and a low density of dislocations on graphene (Gr) buffered sapphire substrate is reported for high‐brightness blue LEDs. Gr films are directly grown on sapphire substrate to avoid the tedious transfer process and GaN is grown by metal–organic chemical vapor deposition (MOCVD). The introduced Gr buffer layer greatly releases biaxial stress and reduces the density of dislocations in GaN film and InxGa1−xN/GaN multiple quantum well structures. The as‐fabricated LED devices therefore deliver much higher light output power compared to that on a bare sapphire substrate, which even outperforms the mature process derived counterpart. The GaN growth on Gr buffered sapphire only requires one‐step growth, which largely shortens the MOCVD growth time. This facile strategy may pave a new way for applications of Gr films and bring several disruptive technologies for epitaxial growth of GaN film and its applications in high‐brightness LEDs.
Materials Science in Finland
Authors: Santos Hélder A.
Published: June 2018

This Special Issue is dedicated to current research activities on Materials Science in Finland, providing a collection of outstanding contributions from diverse research groups on the recent progress regarding silicon and silica nanomaterials, DNA nanotechnology, micro/nano‐motors, biomass‐based nanostructures, nanocellulose, 2D layered materials, atomic layer deposition, superhydrophobic surfaces, and microrobots, from the University of Helsinki, Aalto University, VTT, the University of Turku, Åbo Akademi University, Tampere University of Technology, and the University of Eastern Finland.
Contact Angle Analysis for the Prediction of Defect States of Graphene Grafted with Functional Groups
Authors: Bong Jihye , Park Ju Hyun , Lim Taekyung , Kang Seok Ju , Kwak Sang Kyu , Ju Sanghyun
Published: June 2018

Mass production of graphene is being actively pursued for applications in electronics and energy devices. However, a rapid and simple method to identify the defect states of graphene (which significantly affects the electronic property), prior to the fabrication of the devices, needs to be developed. The manufacturing process requires an easy assessment tool to identify the characteristics of the defects while avoiding cumbersome measurements. This study demonstrates the contact angle analysis to be a plausible assessment tool with the help of molecular dynamics simulations and experiments. The simulations are performed for water droplets on graphene grafted with the most probable functional groups. The contact angle and the shape of the water droplets are interpreted to estimate the type and density of the defects in graphene. This technique can be used as a screening step to identify defective graphene.
Tuning Excitonic Properties of Pure and Mixed Halide Perovskite Thin Films via Interfacial Engineering
Authors: Nikolaidou Katerina , Sarang Som , Martin Denzal , Tung Vincent , Lu Jennifer Q. , Ghosh Sayantani
Published: June 2018

The authors explore the potential of ZnO layers of different morphologies, including single crystalline, micro‐structured, and nano‐structured substrates, for tuning exciton binding energy and influencing charge extraction when interfaced with pure (CH3NH3PbI3) and mixed (CH3NH3PbI3−xClx) halide hybrid perovskite (PVSK) thin films. Electron microscopy characterization of the PVSK/ZnO interfaces are correlated with charge transfer properties, probed by means of temperature, power, and time‐resolved photoluminescence (PL) spectroscopy. The results show that at room temperature, the single crystalline ZnO film promotes PL quenching, and reduces recombination lifetime along with exciton density in the PVSK films, all indicative of efficient electron extraction. Nevertheless, the micro‐structured ZnO layers exhibit a mild increase of the PVSK PL at room temperature, and the nano‐structured ZnO enhances PL by up to several thousand‐fold, while simultaneously enhancing recombination rates by 50%. These trends are temperature dependent, and the findings highlight two opposing aspects of how excitonic dissociation in PVSK thin films is affected by the morphology of the underlying ZnO layers. While the single crystalline ZnO can be leveraged as an efficient electron extraction layer for application in photovoltaic devices, the micro‐ and nano‐structured ones offer potential new opportunities for utilization of high quantum yield hybrid perovskites in opto‐electronic platforms.
Sandwich‐Like FeCl3@C as High‐Performance Anode Materials for Potassium‐Ion Batteries
Authors: Li Deping , Zhu Min , Chen Lina , Chen Long , Zhai Wei , Ai Qing , Hou Guangmei , Sun Qing , Liu Yang , Liang Zhen , Guo Shirui , Lou Jun , Si Pengchao , Feng Jinkui , Zhang Lin , Ci Lijie
Published: June 2018

Carbon materials are used as the anode materials of potassium‐ion batteries (KIBs) thanks to the feasible intercalation of potassium ions. However, their rate capability and cycling performance are still unsatisfactory. In this work, FeCl3‐intercalated expanded graphite (FeCl3‐EG) is first reported as an excellent anode material of KIBs. Attributed to the unique structure with FeCl3 sandwiched between the adjacent graphene layers, the FeCl3‐EG electrode delivers a high reversible capacity of 269.5 mAh g−1 at 50 mA g−1 and 133.1 mAh g−1 at an ultrahigh current density of 5000 mA g−1. The FeCl3‐EG electrode also exhibits an ultrastable cycling performance. Even after 500 cycles at the current density of 50 mA g−1, the FeCl3‐EG electrode can still deliver a discharge capacity of 224.1 mAh g−1 with a high capacity retention of ≈88.82%. Moreover, the FeCl3‐EG electrode is measured at an ultrahigh current density of 2000 mA g−1 for 1300 cycles, with a high capacity retention of ≈70.38%. Ex situ X‐ray diffraction, Raman, and high‐resolution transmission electron microscopy measurements are performed to investigate the potassium storage mechanism of FeCl3‐EG electrode, which confirms the FeCl3‐EG a promising anode material for high‐performance KIBs.
Micropatterned Elastic Gold‐Nanowire/Polyacrylamide Composite Hydrogels for Wearable Pressure Sensors
Authors: Yin Ming‐jie , Zhang Yangxi , Yin Zhigang , Zheng Qingdong , Zhang A. Ping
Published: June 2018

Elastic hydrogels have recently attracted remarkable attention because of their unique mechanical and stimulus‐responsive properties. In this work, a novel elastic supramolecular hydrogel for wearable pressure sensors is developed by photocrosslinking polyacrylamide (PAAm) through covalent bonds and hydrogen bonds as well as ionic bonds in the presence of poly(acrylic acid) and Ca2+. Gold nanowires (Au NWs) are homogeneously mingled with the PAAm hydrogel to attain a conductive composite hydrogel. Using an in‐house optical maskless exposure technology, printable piezoresistive pressure sensors are quickly fabricated by directly patterning the composite hydrogel into microribs on flexible electrodes. The pressure sensors with microrib structures exhibit a bimodal contact mode between Au NWs, which provides a new pathway to engineer the sensor's sensitivity and operation range. In the experiments, the pressure sensor with optimized microrib structures shows not only ultrahigh sensitivity (i.e., 3.71 kPa−1 in the pressure range of 0–2.8 kPa) but also low detection limit (i.e., 0.2 Pa) and long‐term stability. A flexible hand‐shape electrode device and an arterial pulse monitoring sensor are demonstrated to reveal the potentials of such a pressure sensor on wearable device applications.
Sulfinate‐Organocatalyzed (3+2) Annulation of Allenyl Sulfones with 1,1‐Dicyano Olefins in the Presence of a Quaternary Ammonium Phase Transfer Agent
Authors: Martzel Thomas , Lohier Jean‐François , Gaumont Annie‐Claude , Brière Jean‐François , Perrio Stéphane
Published: June 2018

The benzenesulfinate‐catalyzed (3+2) annulation between allenyl sulfones and aryl(alkyl)idenemalononitriles has been developed under mild phase transfer conditions, affording a breadth of functionalized sulfonyl cyclopentenes in good to excellent yields (22 examples, 49–99%) and high diastereoselectivities. These adducts were likely generated, via an allylsulfone anion featuring a quaternary ammonium cation.

magnified image
Unexpected Decarboxylation‐Triggered o‐Hydroxyl‐Controlled Redox Condensation of Phenylglycines with 2‐Nitrophenols in Aqueous Media
Authors: Tang Lin , Yang Zhen , Sun Tian , Zhang Di , Ma Xiantao , Rao Weihao , Zhou Yuqiang
Published: June 2018

A decarboxylation‐triggered and o‐hydroxyl‐controlled hydrogen‐transfer strategy for the one‐pot synthesis of benzoxazoles from readily available amino acids and 2‐nitrophenols is reported. On the basis of this autoredox reaction, the C−N bond can be efficiently constructed to afford the desired products in moderate to good yields under transition‐metal‐free conditions in aqueous media.

magnified image
Effect of plasticizers on physicochemical properties of cellulose nanocrystals filled alginate bionanocomposite films
Authors: El Miri Nassima , Aziz Faissal , Aboulkas Adil , El Bouchti Mehdi , Ben Youcef Hicham , El Achaby Mounir
Published: June 2018

In this work, the effect of various polyol‐based plasticizers, including glycerol (GLY), diethylene glycol (DEG), and polyethylene glycol (PEG), on the properties of alginate (ALG)‐based films and cellulose nanocrystals (CNC)‐filled ALG‐based bionanocomposite films was investigated. The CNC used as nanoreinforcing fillers were extracted, at nanometric scale, from sugarcane bagasse fibers using sulfuric acid hydrolysis process, and their morphology and structure were characterized. Plasticized ALG films and plasticized ALG‐CNC bionanocomposite films were prepared by solvent casting method. Before the casting process, the steady shear viscosity of film‐forming solutions of all studied formulations was studied and compared. The obtained ALG‐based films were successfully characterized in terms of their structure, transparency, water vapor permeability (WVP), moisture uptake (MU), thermal, and mechanical properties. It was found that all studied plasticized films keep the same transparency level of neat ALG films, thus suggesting that the selected plasticizers are compatible with the ALG biopolymer, and the CNC are well dispersed within the bionanocomposite films. The elastic modulus and tensile strength of neat ALG films were largely decreased after the addition of different plasticizers, while the elongation at break was significantly increased. However, these selected mechanical parameters were simultaneously improved when CNC are incorporated into plasticized ALG bionanocomposite films. The WVP and MU properties of ALG films were decreased when different plasticizers and CNC were added. Herein, the steps to form new eco‐friendly ALG films were described by taking advantage of the combination of plasticizers and CNC with ALG biopolymer. The as‐produced films exhibited good optical transparency while reducing the WVP and enhancing tensile properties, which are the main properties required for packaging applications.
A transcriptome screen for positive selection in domesticated breadfruit and its wild relatives (Artocarpus spp.)
Authors: Laricchia Kristen M. , Johnson Matthew G. , Ragone Diane , Williams Evelyn W. , Zerega Nyree J. C. , Wickett Norman J.
Published: June 2018

Premise of the Study

Underutilized crops, such as breadfruit (Artocarpus altilis, Moraceae) have the potential to improve global food security. Humans have artificially selected many cultivars of breadfruit since its domestication began approximately 3500 years ago. The goal of this research was to identify transcriptomic signals of positive selection and to develop genomic resources that may facilitate the development of improved breadfruit cultivars in the future.

Methods

A reference transcriptome of breadfruit was assembled de novo and annotated. Twenty‐four transcriptomes of breadfruit and its wild relatives were generated and analyzed to reveal signals of positive selection that may have resulted from local adaptation or natural selection. Emphasis was placed on MADS‐box genes, which are important because they often regulate fruiting timing and structures, and on carotenoid biosynthesis genes, which can impact the nutritional quality of the fruit.

Key Results

Over 1000 genes showed signals of positive selection, and these genes were enriched for localization to plastids. Nucleotide sites and individuals under positive selection were discovered in MADS‐box genes and carotenoid biosynthesis genes, with several sites located in cofactor or DNA‐binding domains. A McDonald–Kreitman test comparing wild to cultivated samples revealed selection in one of the carotenoid biosynthesis genes, abscisic acid 8′‐hydroxylase 3.

Conclusions

This research highlights some of the many genes that may have been intentionally or unintentionally selected for during the human‐mediated dispersal of breadfruit and stresses the importance of conserving a varied germplasm collection. It has revealed candidate genes for further study and produced new genomic resources for breadfruit.
Photoredox Catalysis of Cyclometalated IrIII Complex for the Conversion of Amines to Fluorinated Alkyl Amides
Authors: Ng Chi‐On , Feng Hua , Cheng Shun‐Cheung , Xiao Yelan , Lo Larry Tso‐Lun , Ko Chi‐Chiu
Published: June 2018

Using luminescent cyclometalated IrIII complex as photocatalyst, a new visible‐light induced photocatalytic method for the preparation of perfluorinated alkyl amides under a mild condition has been developed. Primary aliphatic, secondary aliphatic and aromatic amines as well as perfluoroalkyl iodides and bromides can be used as the substrates in the photocatalytic reactions. On the basis of the emission quenching study and the characterizations of the reaction intermediates, the mechanism of the photocatalysis has been proposed.
Templat‐ und metallfreie Synthese stickstoffreicher, nanoporöser und “edler” Kohlenstoffmaterialien durch direkte Kondensation eines vororganisierten Hexaazatriphenylen Vorläufers
Authors: Walczak Ralf , Kurpil Bogdan , Savateev Aleksandr , Heil Tobias , Schmidt Johannes , Qin Qing , Antonietti Markus , Oschatz Martin
Published: June 2018

Poröse und oxidationsresistente (“edle”) Kohlenstoffmaterialien werden durch gezielte thermische Umwandlung eines Hexaazatriphenylen‐Vorläufers hergestellt. Einfache thermische Kondensation der vororganisierten molekularen Präkursorverbindung führt zu stickstoffreichen Kohlenstoffen mit C2N‐artiger Stöchiometrie. Trotz der Abwesenheit jeglicher Porogene und Metallspezies erreichen die spezifischen Oberflächen der molekularen Kohlenstoffe aufgrund ihrer signifikanten Mikroporosität bis zu 1000 m2 g−1. Anteil und Art der Stickstoffspezies können über die Synthesetemperatur kontrolliert werden, während die Porosität weitgehend unbeeinflusst bleibt. Die resultierenden edlen Kohlenstoffe haben eine stark polarisierende mikroporöse Struktur und zeigen daher besonders hohe Adsorptionsaffinitäten zu Molekülen wie H2O und CO2. Dieses Prinzip der vororganisierten Präkursoren eröffnet neue Möglichkeiten für die Synthese poröser edler Kohlenstoffe unter molekularer Kontrolle, die Zugang zu den speziellen physikalischen Eigenschafften der C2N‐Struktur schafft und damit das bekannte Spektrum der klassischen porösen Kohlenstoffe erweitert.
BODIPY Peptide Labeling by Late‐Stage C(sp3)−H Activation
Authors: Wang Wei , Lorion Mélanie M. , Martinazzoli Oscar , Ackermann Lutz
Published: June 2018

Late‐stage BODIPY diversification of structurally complex amino acids and peptides was accomplished by racemization‐free palladium‐catalyzed C(sp3)−H activation. Transformative fluorescence modification proved viable by triazole‐assisted C(sp3)−H arylation in a chemo‐ and site‐selective fashion, providing modular access to novel BODIPY peptide sensors.
Template‐ and Metal‐Free Synthesis of Nitrogen‐Rich Nanoporous “Noble” Carbon Materials by Direct Pyrolysis of a Preorganized Hexaazatriphenylene Precursor
Authors: Walczak Ralf , Kurpil Bogdan , Savateev Aleksandr , Heil Tobias , Schmidt Johannes , Qin Qing , Antonietti Markus , Oschatz Martin
Published: June 2018

The targeted thermal condensation of a hexaazatriphenylene‐based precursor leads to porous and oxidation‐resistant (“noble”) carbons. Simple condensation of the pre‐aligned molecular precursor produces nitrogen‐rich carbons with C2N‐type stoichiometry. Despite the absence of any porogen and metal species involved in the synthesis, the specific surface areas of the molecular carbons reach up to 1000 m2 g−1 due to the significant microporosity of the materials. The content and type of nitrogen species is controllable by the carbonization temperature whilst porosity remains largely unaffected at the same time. The resulting noble carbons are distinguished by a highly polarizable micropore structure and have thus high adsorption affinity towards molecules such as H2O and CO2. This molecular precursor approach opens new possibilities for the synthesis of porous noble carbons under molecular control, providing access to the special physical properties of the C2N structure and extending the known spectrum of classical porous carbons.
Head–Tail Asymmetry as the Determining Factor in the Formation of Polymer Cubosomes or Hexasomes in a Rod–Coil Amphiphilic Block Copolymer
Authors: Lyu Xiaolin , Xiao Anqi , Zhang Wei , Hou Pingping , Gu Kehua , Tang Zhehao , Pan Hongbing , Wu Fan , Shen Zhihao , Fan Xing‐He
Published: June 2018

The self‐assembly of a rod–coil amphiphilic block copolymer (ABCP) led to Im
m and Pn
m polymer cubosomes and p6mm polymer hexasomes. This is the first time that these structures are observed in a rod–coil system. By varying the hydrophobic chain length, the initial concentration of the polymer solution, or the solubility parameter of the mixed solvent, head–tail asymmetry is adjusted to control the formation of polymer cubosomes or hexasomes. The formation mechanism of the polymer cubosomes was also studied. This research opens up a new way for further study of the bicontinuous and inverse phases in different ABCP systems.
B(C6F5)3 catalysis accelerates the hydrosilane chlorination by Ph3CCl
Authors: Šimarek Adam , Lamač Martin , Horáček Michal , Pinkas Jiří
Published: June 2018

A chlorination of tertiary (5 examples), secondary (3 examples) and primary (PhSiH3) hydrosilanes by Ph3CCl with a catalytic amount of B(C6F5)3 is presented. The reaction was substantially faster than its non‐catalyzed version. The chlorination of secondary hydrosilanes and PhSiH3 proceeded in a stepwise manner, which allowed selective isolation of chlorohydrosilanes. The mechanism of catalytic hydrosilane chlorination seems to be distinct to mainstream B(C6F5)3 catalyzed reactions involving hydrosilanes (i.e. activation of Si‐H bond by the R3Si‐‐H‐‐B (C6F5)3 adduct formation). Contrary, the present process is based on an instant formation of [Ph3C]+[ClB(C6F5)3]− from B(C6F5)3 and Ph3CCl, followed by a hydride transfer from particular hydrosilane to tritylium cation with a concomitant generation of unstable silylium cation compensated by borate anion [ClB(C6F5)3]−. Subsequent decomposition of this ionic species leads to the corresponding chlorosilane and recuperation of B(C6F5)3.
Investigation of the Relationship Between Susceptibility Loci for Hip Osteoarthritis and Dual X‐Ray Absorptiometry–Derived Hip Shape in a Population‐Based Cohort of Perimenopausal Women
Authors: Baird Denis A. , Paternoster Lavinia , Gregory Jennifer S. , Faber Benjamin G. , Saunders Fiona R. , Giuraniuc Claudiu V. , Barr Rebecca J. , Lawlor Deborah A. , Aspden Richard M. , Tobias Jonathan H.
Published: June 2018

Objective

To examine relationships between known osteoarthritis (OA) susceptibility loci and hip shape in a population‐based cohort of perimenopausal women in order to investigate whether hip shape contributes to OA development.

Methods

Hip shape was measured, using statistical shape modeling, on dual x‐ray absorptiometry scans of the hip from mothers in the Avon Longitudinal Study of Parents and Children (ALSPAC). The proximal femur and superior acetabulum were outlined, and independent hip shape modes were generated. In a subregional model, points were restricted to the acetabulum and superior femoral head. Associations between 11 OA‐related single‐nucleotide polymorphisms, identified by literature search, and shape modes were analyzed in a multivariate canonical correlation analysis.

Results

A total of 3,111 women (mean age 48 years) had genetic and hip shape data. The KLHDC5/PTHLH rs10492367 OA risk allele was associated with a wider upper femur in the whole shape model (P = 1 × 10−5). The DOT1L rs12982744 OA risk allele was associated with reduced superior joint space in the subregional shape model (P = 2 × 10−3). The COL11A1 rs4907986 OA risk allele was associated with lateral displacement of the femoral head relative to the acetabulum in the subregional shape model (P = 5 × 10−4). Regional association plots identified an additional COL11A1 locus in moderate linkage disequilibrium with rs4907986, which was more strongly associated with hip shape (rs10047217; P = 3 × 10−6). Colocalization analysis indicated sharing of genetic signals for hip shape and hip OA for the KLHDC5/PTHLH and COL11A1 loci.

Conclusion

Hip OA susceptibility loci were associated with shape in this study, suggesting that these loci (and potentially yet‐to‐be‐identified hip OA loci) could contribute to hip OA in later life via perturbing biologic pathways that mediate morphology development.
Stabbewehrung aus Carbonfaserverstärktem Beton (CFB) für den Betonbau
Authors: Ortlepp Sebastian , Zernsdorf Kai , Schladitz Frank , Bösche Thomas
Published: June 2018

Im Großforschungsprojekt C3 – Carbon Concrete Composite werden zukunftsweisende Bewehrungssysteme aus Carbon für den Betonbau entwickelt. Dabei werden mattenartige und stabförmige Bewehrungen betrachtet. Bisher enthalten diese Carbonbewehrungen, neben den Carbonfilamenten, vorwiegend eine Kunststoffmatrix, die die Tausenden Carbonfilamente zu einem Querschnitt zusammenfasst. Wissenschaftler der HTW Dresden und der TU Dresden verfolgen aktuell einen Ansatz, diese Kunststoffmatrix durch eine mineralische Matrix zu ersetzen, um damit die Eigenschaften der Carbonbewehrung weiter zu verbessern und um das Anwendungsfeld zu vergrößern. In diesem Beitrag werden das Grundprinzip der neuartigen Bewehrung für den Betonbau sowie zugehörige Tastversuche präsentiert. Dies soll ein Anstoß für die weitere Forschung auf diesem Gebiet sein.
Neuroimaging Studies Illustrate the Commonalities Between Ageing and Brain Diseases
Authors: Cole James H.
Published: June 2018

The lack of specificity in neuroimaging studies of neurological and psychiatric diseases suggests that these different diseases have more in common than is generally considered. Potentially, features that are secondary effects of different pathological processes may share common neurobiological underpinnings. Intriguingly, many of these mechanisms are also observed in studies of normal (i.e., non‐pathological) brain ageing. Different brain diseases may be causing premature or accelerated ageing to the brain, an idea that is supported by a line of “brain ageing” research that combines neuroimaging data with machine learning analysis. In reviewing this field, I conclude that such observations could have important implications, suggesting that we should shift experimental paradigm: away from characterizing the average case‐control brain differences resulting from a disease toward methods that place individuals in their age‐appropriate context. This will also lead naturally to clinical applications, whereby neuroimaging can contribute to a personalized‐medicine approach to improve brain health.
Enzymatic and chemical synthesis of new anticoagulant peptides
Authors: Origone Anabella , Bersi Grisel , Illanes Andrés , Sturniolo Héctor , Liggieri Constanza , Guzmán Fanny , Barberis Sonia
Published: June 2018

In this study we report the enzymatic synthesis of N‐α‐[Carbobenzyloxy]‐Tyr‐Gln‐Gln (Z‐YQQ), a new anticoagulant tripeptide. It was obtained using phytoproteases from the stems and petioles of Asclepias curassavica L. as catalyst in an aqueous–organic biphasic system formed by 50% (v/v) ethyl acetate and 0.1 M Tris–HCl buffer pH 8. The resulting peptide was compared with the analogous peptide Tyr‐Gln‐Gln (YQQ) produced by solid‐phase chemical synthesis. The in vitro anticoagulant activity of the aforementioned peptides was determined using Wiener Lab Test (Wiener, Argentina). The toxicological activity of the peptides was also determined. The enzymatically synthesized Z‐YQQ peptide acted on the extrinsic pathway of the coagulation cascade, delaying the conversion time of prothrombin to thrombin and fibrinogen to fibrin by 136 and 50%, respectively, with respect to the controls. The chemically synthesized YQQ peptide acted specifically on the intrinsic pathway of the coagulation cascade, affecting factors VIII, IX, XI, and XII from such cascade, and increasing the coagulation time by 105% with respect to the control. The results suggest that two new anticoagulant peptides (Z‐YQQ and YQQ) can be useful for safe pharmaceutical applications. Nevertheless, some aspects related to peptide production should be optimized. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 2018 © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 34:1093–1101, 2018
Characterization of biogenic Fe (III)‐binding exopolysaccharide nanoparticles produced by Ralstonia sp. SK03
Authors: Kianpour Sedigheh , Ebrahiminezhad Alireza , Negahdaripour Manica , Mohkam Milad , Mohammadi Fatemeh , Niknezhad Seyyed Vahid , Ghasemi Younes
Published: June 2018

A new technological approach to nanoparticle synthesis is using microorganisms, such as bacteria, which have the ability to synthesize nontoxic nanoparticles with high biocompatibility. In addition, bacteria have strict control over size, structure, shape, and dimension of produced nanoparticles. In the present work, Fe (III)‐binding exopolysaccharide (Fe‐EPS) nanoparticles were biosynthesized by Ralstonia pickettii sp. SK03, a bacterium isolated from a mineral spring. 16S rRNA gene sequencing and biochemical tests were done for identification of the isolated bacterium. For the first time, critical biological and physicochemical properties of this iron oxide nanoparticle were characterized using Fourier Transform Infrared (FTIR) Spectroscopy, Transmission Electron Microscopy (TEM), Vibrating Sample Magnetometer (VSM), Dynamic Light Scattering (DLS), Thermogravimetric analysis (TGA), X‐ray crystallography (XRD), Atomic absorption spectroscopy (AAS), and cell viability assays (MTT assay). The characterization results showed that Fe‐EPS nanoparticles were composed of spherical ferrihydrite nanoparticles (with a size range of 1.2–2 nm), trapped in a polysaccharide matrix. The TGA analysis demonstrated that Fe‐EPS nanoparticles contained ∼25.2% polysaccharide. Therefore, this polysaccharide matrix showed a very low magnetic saturation value (0.25 emu/g) and a large negative charge of −93.8 mV. In addition, treatment of hepatocarcinoma cell line (Hep‐G2) with 1–500 µg/mL concentrations of Fe‐EPS nanoparticles caused 40% increase in the cell viability, which indicated that the biosynthesized nanoparticles were nontoxic and biocompatible. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 2018 © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 34:1167–1176, 2018
Improved recovery of bacteriophage M13 using an ATPS‐based bioprocess
Authors: González‐Mora Alejandro , Ruiz‐Ruiz Federico , Benavides Jorge , Rito‐Palomares Marco
Published: June 2018

Aqueous two‐phase systems (ATPS) have been widely exploited for the recovery and partial purification of biological compounds. Recently our research group characterized the primary recovery and partial purification of bacteriophage M13 using polymer‐salt and ionic liquid‐salt ATPS. From such study, it was concluded that PEG 400‐potassium phosphate ATPS with a volume ratio (VR) of 1 and 25% w/w TLL were the best suitable for the primary recovery of bacteriophage M13 from a crude extract, achieving a recovery yield of 83.3%. Although such system parameters were proven to be adequate for the recovery of the product of interest, it was concluded that further optimization was desirable and attainable by studying the effect of additional system parameters such as VR, concentration of neutral salt (M) and sample load (% w/w). This research work presents an optimization of a previously reported process for the recovery of bacteriophage M13 directly from a crude extract using ATPS. The increase in VR and sample load showed a positive effect in the recovery of M13 indicating an improved performance of the proposed ATPS. According to the results presented here, a system composed of PEG 400 17.2% (w/w), potassium phosphate 15.5% (w/w) and a sample load of 30% (w/w) allowed the recovery of M13 directly from a crude extract with a top phase recovery of 80.1%, representing an increase of 4.8 times in the final concentration and a reduction of 2.65 times in the processing costs. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 2018 © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 34:1177–1184, 2018
Comparison of time‐gated surface‐enhanced raman spectroscopy (TG‐SERS) and classical SERS based monitoring of Escherichia coli cultivation samples
Authors: Kögler Martin , Paul Andrea , Anane Emmanuel , Birkholz Mario , Bunker Alex , Viitala Tapani , Maiwald Michael , Junne Stefan , Neubauer Peter
Published: June 2018

The application of Raman spectroscopy as a monitoring technique for bioprocesses is severely limited by a large background signal originating from fluorescing compounds in the culture media. Here, we compare time‐gated Raman (TG‐Raman)‐, continuous wave NIR‐process Raman (NIR‐Raman), and continuous wave micro‐Raman (micro‐Raman) approaches in combination with surface enhanced Raman spectroscopy (SERS) for their potential to overcome this limit. For that purpose, we monitored metabolite concentrations of Escherichia coli bioreactor cultivations in cell‐free supernatant samples. We investigated concentration transients of glucose, acetate, AMP, and cAMP at alternating substrate availability, from deficiency to excess. Raman and SERS signals were compared to off‐line metabolite analysis of carbohydrates, carboxylic acids, and nucleotides. Results demonstrate that SERS, in almost all cases, led to a higher number of identifiable signals and better resolved spectra. Spectra derived from the TG‐Raman were comparable to those of micro‐Raman resulting in well‐discernable Raman peaks, which allowed for the identification of a higher number of compounds. In contrast, NIR‐Raman provided a superior performance for the quantitative evaluation of analytes, both with and without SERS nanoparticles when using multivariate data analysis. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 34:1533–1542, 2018
Characterization of phenotypic and genotypic diversity in subclones derived from a clonal cell line
Authors: Tharmalingam Tharmala , Barkhordarian Hedieh , Tejeda Nicole , Daris Kristi , Yaghmour Sam , Yam Pheng , Lu Fang , Goudar Chetan , Munro Trent , Stevens Jennitte
Published: June 2018

Regulatory guidelines require the sponsors to provide assurance of clonality of the production cell line, and when such evidence is not available, additional studies are typically required to further ensure consistent long‐term manufacturing of the product. One potential approach to provide such assurance of clonal derivation of a production cell line is to characterize subclones generated from the original cell line and assess their phenotypic and genotypic similarity with the hypothesis that cell lines derived from a clonal bank will share performance, productivity and product quality characteristics. In this study, a production cell line that was cloned by a validated FACS approach coupled with day 0 imaging for verification of single‐cell deposition was subcloned using validated FACS and imaging methods. A total of 46 subclones were analyzed for growth, productivity, product quality, copy number, and integration site analysis. Significant diversity in cell growth, protein productivity, product quality attributes, and copy number was observed between the subclones, despite stability of the parent clone over time. The diversity in protein productivity and quality of the subclones were reproduced across time and production scales, suggesting that the resulting population post sub‐cloning originating from a single cell is stable but with unique properties. Overall, this work demonstrates that the characteristics of isolated subclones are not predictive of a clonally derived parental clone. Consequently, the analysis of subclones may not be an effective approach to demonstrate clonal origin of a cell bank. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 34:613–623, 2018
Immobilization of tobacco etch virus (TEV) protease on a high surface area protein nanofibril scaffold
Authors: Raynes Jared K. , Domigan Laura J. , Pearce F. Grant , Gerrard Juliet A.
Published: June 2018

Tobacco etch virus (TEV) protease is widely used for the removal of poly‐histidine affinity tags from proteins. In solution, it is a one‐time use enzyme for tag cleavage that has low stability, and is therefore a good candidate for immobilization. Amyloid fibrils can act as a versatile nanoscaffold by providing a large surface area for biomolecule immobilization. Immobilization of TEV protease to amyloid fibrils grown from the surface of a small glass bead, using physisorption, successfully immobilized active TEV protease. The bead retained activity over several uses and successfully cleaved a poly‐histidine tag from several his‐tagged proteins. This is first time that TEV protease has been immobilized to insulin amyloid fibrils, or any protein based support. Such functionalized surface assembled amyloid fibrils show promise as a novel nanosupport for the creation of functional bionanomaterials, for example, active surface coatings for the production of fine chemicals, chemical detoxification, or biosensing. Insulin amyloid fibrils provide a new nanosupport for the immobilization of TEV protease, which could allow for the reuse of the enzyme, saving on production costs for recombinantly expressed poly‐histidine tagged proteins. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 34:1506–1512, 2018
Kinetically Controlled Polymorphic Superstructures of Pyrene‐Based Asymmetric Liquid Crystal Dendron: Relationship Between Hierarchical Superstructures and Photophysical Properties
Authors: Park Minwook , Kang Dong‐Gue , Choi Yu‐Jin , Yoon Won‐Jin , Koo Jahyeon , Park Seo‐Hee , Ahn Seokhoon , Jeong Kwang‐Un
Published: June 2018

To understand the relationship between kinetically controlled hierarchical superstructures and photophysical properties, pyrene‐based asymmetric liquid crystal (LC) dendrons (abbreviated as PD) were newly synthesized by covalently attaching a pyrene moiety (P) at a biphenyl‐based LC dendritic group (D). The phase transition behavior of PD has been systematically studied with a combined technique of thermal analysis, microscopy, spectroscopy, and scattering analysis. PD formed two different crystalline structures depending on the cooling rate: a stable crystalline phase (Ks, slow cooling) and a metastable crystalline phase (Kms, quenching). The kinetically controlled molecular packing structures of PD depend on the competition and cooperation of intermolecular physical interactions with nanophase separation. Upon slow cooling, the PD dimer formed by intermoelcular H‐bonding constructed a layered hierarchical structure with the help of nanophase separation. Owing to the strong π–π stacking (J‐aggregation) with weak H‐bondings, the PD dimer in the layer was slightly tilted to give a monoclinic layered structure with a periodic layer d‐spacing of 6.6 nm. In contrast, the metastable Kms phase formed by the quenching process showed a significant tilt of the PD dimer in the layer (d‐spacing=4.4 nm) due to the weak π–π stacking (H‐aggregation) and the strong H‐bondings.