bluuebunny/crossref_metadata_2025 huggingface dataset:
The effect of cationic groups on the stability of 19F MRI contrast agents in nanoparticles
Authors: Piloni Alberto , Simonutti Roberto , Stenzel Martina H.
Published: April 2019

Fluorine‐19 (19F)‐based contrast agents are increasingly used for magnetic resonance imaging. Conjugated to polymers, they provide an excellent quantitative imaging tool to detect the movement of the polymeric nanoparticles in vivo as there is no background signal in tissue. One of the challenges is the decline in signal intensity when the conjugated hydrophobic fluorinated functionalities aggregate. Therefore, a new fluorinated monomer was prepared from l‐arginine that carries a 2,2,2‐trifluoroethyl functional group for imaging. The resulting monomer, 2,2,2‐trifluoroethylamide l‐arginine methacrylamide (3FArgMA), was copolymerized with poly(ethylene glycol) methyl ether methacrylate (PEGMEMA), [2‐(2,3,4,6‐tetra‐O‐acetyl‐α‐d‐mannopyranosyloxy)ethyl methacrylate or 1‐O‐methacryloyl‐2,3:4,5‐di‐O‐isopropylidene‐β‐d‐fructopyranose, respectively, using poly(methyl methacrylate) macro‐reversible addition–fragmentation chain transfer polymerization agent. The resulting block copolymers, which varied in 3FArgMA content, were self‐assembled into micelles of hydrodynamic diameters from 25 to 60 nm. The permanently positively charged arginine functionality on the 3FArgMA displayed repulsive forces against aggregation enabling high spin–spin relaxation times (T2) in acidic as well as alkaline solutions. However, the longer poly(ethylene glycol) side functionality in PEGMEMA enabled better steric stabilization (T2~30 ms) while the short fructose side chain was not enough to maintain high T2 values, in particular when a higher 3FArgMA content was used. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1994–2001
Experimental Observation and Characterization of B−HTPB‐based Solid Fuel with Addition of Iron Particles for Hybrid Gas Generator in Ducted Rocket Applications
Authors: Hashim Syed Alay , Ojha Pawan Kumar , Karmakar Srinibas , Roy Arnab , Chaira Debasis
Published: April 2019

An extensive diversity in the formulation of HTPB‐based solid fuels with metal additives has now been accepted in rocket and missile applications. Boron, which is a metalloid and often occurs in compound form has maintained its dominance mainly due to its significant theoretical energy potential. Therefore, it is preferred as the primary choice for rockets and solid fuel ramjet (SFRJ) or ducted rocket (SFDR). In this paper, performance enhancement of B−HTPB‐based solid fuel is assessed through a rapid screening tool which is called an opposed flow burner (OFB). Screened fuel combinations may be further evaluated in the gas generator of a ducted rocket (DR) to fulfill the intention of the present investigation. The baseline fuel (B−HTPB) is included with a metal fuel/catalyst (iron) with the expectation that it would enhance the combustion performance of boron. Boron−iron loading has been taken 10 % of the total sample weight (wt.) giving a wt. ratio of 90 : 10. Pure oxygen has been used as an oxidizer which impinges on the fuel surface where oxygen mass flux (Gox) varies between 20–57 kg/m2‐s. In this study, the research focuses mainly on regression rate and amount of residual active boron in the condensed combustion product (CCP) of the samples. Addition of iron to B−HTPB increases the regression rate by around 12 % and active boron content in CCP reduces significantly to 2.5 % compared to 16 % of the baseline fuel. In addition to that, the heating value of the fuel samples and identification of gas phase intermediate species (OH, CH, C2, BO, BO2) are the other vital investigations undertaken in the present study.
Infiltrating CD4+ T cells attenuate chemotherapy sensitivity in prostate cancer via CCL5 signaling
Authors: Xiang Peng , Jin Song , Yang Yang , Sheng Jindong , He Qun , Song Yi , Yu Wei , Hu Shuai , Jin Jie
Published: April 2019

Background

Chemotherapy with Docetaxel (Doc) is efficient in a subset of prostate cancer (PCa) cases; however, most patients ultimately develop resistance to Docetaxel. The tumor immune microenvironment and secreted cytokines play a substantial role in development of resistance to chemotherapy. Our previous study has demonstrated that CD4+ T cells in prostate tumor microenvironment contribute to PCa progression; meanwhile, we found increased CD4+ T‐cell infiltration in tumor area after Doc treatment; however, their effects on PCa chemosensitivity remain unclear. Here, we aim to explore the role and mechanisms of CD4+ T cells in PCa chemotherapy sensitivity.

Methods

CD4+ T‐cell infiltration in Doc‐treated paraffin‐embedded specimens from transurethral resection of prostate, radical prostatectomy, or bone metastasis was detected by immunohistochemistry. The castration‐resistant PCa cell lines—C4‐2 and CWR22RV1, and CD4+ T‐cell lines—HH and Molt‐3 were used in the coculture system. After coculture with the lymphocytes, PCa cell chemosensitivity was detected by cell counting kit‐8, terminal deoxynucleotidyl transferase dUTP nick‐end labeling assays, and Western blot analysis. Various cell cytokines were determined by cytokine arrays and reverse‐transcription polymerase chain reaction. The recombinant human C‐C motif chemokine ligand 5 (CCL5) was added to PCa cells for further confirming its effects and anti‐CCL5 antibody was used for neutralization. S3I‐201, a signal transducer and activator of transcription 3 (STAT3) inhibitor, was added to the coculture system to detect STAT3 role in chemosensitivity. Tumor xenografts in nude mice were used for confirming effects of CD4+ T cells in vivo study.

Results

We found more infiltrated CD4+ T cells in human PCa lesions than in the adjacent noncancerous tissues after Doc treatment. In vitro cell line study confirmed that CD4+ T cells increase the PCa Doc resistance. Quantative polymerase chain reaction and cytokine arrays indicated that after coculture with PCa, CD4+ T cells could secrete large amounts of CCL5. Moreover, CCL5 stimulation enhanced PCa resistance to Doc, and anti‐CCL5 antibody could partly reverse this process. We found that CD4+ T cells could activate P‐STAT3 signaling via secreting CCL5 and adding a STAT3 inhibitor can reverse the chemoresistance. In vivo mouse model with xenografted 22RV1 cells and CD4+ T cells also confirmed the in vitro results.

Conclusions

Together, our results indicate that infiltrating CD4+ T cells could promote PCa chemotherapy resistance via modulation of the CCL5/STAT3 signaling pathway.
EMI Shielding Effectiveness and Heater Behavior for Ge IR Windows
Authors: Çat Yunus , Baran Veysel , Özçelik Süleyman
Published: April 2019

In this study, infrared (IR) optic windows having 0.5 mm thickness are produced from n‐type Ge single crystal, which is grown by the Czochralski (CZ) technique. Metallic mesh and antireflective (AR) layer are coated on the Ge windows. Electromagnetic interference (EMI) shielding effectiveness (SE) and heater behavior are determined of the IR windows. Metallic mesh geometry is adjusted zeroth order beam transmittance to be ≈82% combined with a low sheet resistance as ≈1.13 Ω sq−1. Optical transmission (OT) of the Au‐meshed Ge is obtained about 81% by coating the AR layer. SE measurements of the Ge windows having with and without metallic mesh are performed by flanged coaxial SE tester according to the ASTM D4935‐99. The SE value is increased from 2.8 dB (for S1) to 36.3 dB (for S2) owing to the Au mesh. In addition, the heater behavior and IR optical transmission dependent on temperature of the Ge windows are evaluated. The temperature of the Au‐meshed Ge window reaches to around 60 °C end of the 10 s under the 4 V. Finally, decreasing of IR optical transmission and absorbing edge shifting to lower energy of Ge windows are determined as depending on increasing of the temperature.
Prey‐to‐fox isotopic enrichment of 34S in bone collagen: Implications for paleoecological studies
Authors: Krajcarz Maciej T. , Krajcarz Magdalena , Drucker Dorothée G. , Bocherens Hervé
Published: April 2019

Rationale

The trophic enrichment factor (TEF) is a parameter reflecting the difference in isotopic ratio between a consumer's tissues and diet, used in isotopic ecology and paleoecology to track dietary habits. The TEF of sulfur is believed to be low, but was, until now, only documented in a limited number of taxa. In this study we use a subfossil accumulation of bones from a red fox (Vulpes vulpes) den to verify the TEF for sulfur in fox bone collagen.

Methods

Collagen was extracted from 30 samples of subfossil bones, including foxes and their prey. The δ34S values of the bone collagen samples were measured with an elemental analyzer connected to an isotope ratio mass spectrometer. The TEF was calculated as [Δ34S = (mean δ34S in predator) – (mean δ34S in prey)], using taphonomic indices to estimate the mean diet, and calculated separately for different age classes of the predator.

Results

We modeled 12 variants of TEF for different estimations of the diet composition and for three fox age classes (adult, subadult, and juvenile). The estimated TEF values range from −0.54 to +0.03‰ and are similar to TEFs known for other mammals. Absolute TEF values are nearly equal to or lower than the analytical error, which is ±0.4‰.

Conclusions

For the first time, we present direct δ34S data for the bone collagen of a free‐living predator and its naturally selected prey. Our results indicate very low or even slightly negative TEF values for sulfur. Furthermore, according to our results, the δ34S value should not be considered a reliable indicator of trophic position in terrestrial food webs but rather, it should be used to disentangle different food webs based on different primary producers.
Long noncoding RNAs: Novel regulators of virus‐host interactions
Authors: Liu Shaoqiong , Liu Xia , Li Juan , Zhou Hong , Carr Michael J. , Zhang Zhenjie , Shi Weifeng
Published: April 2019

Long noncoding RNAs (lncRNAs) represent a key class of cellular regulators, involved in the modulation and control of multiple biological processes. Distinct classes of lncRNAs are now known to be induced by host cytokines following viral infections. Current evidence demonstrates that lncRNAs play essential roles at the host‐pathogen interface regulating viral infections by either innate immune responses at various levels including activation of pathogen recognition receptors or by epigenetic, transcriptional, and posttranscriptional effects. We review the newly described mechanisms underlying the interactions between lncRNAs, cytokines, and metabolites differentially expressed following viral infections; we highlight the regulatory networks of host antiviral responses and emphasize the need for interdisciplinary research between lncRNA biology and immunology to deepen understanding of viral pathogenesis.
Cascade‐amplification of therapeutic efficacy: An emerging opportunity in cancer treatment
Authors: Li Menghuan , Luo Zhong , Peng Zhihong , Cai Kaiyong
Published: April 2019

Increasing research evidence reveals that cancer is complex disease involving many biological factors, processes and systems, which may severely limit the actual efficacy of conventional monotonic anticancer approaches. To overcome these obstacles in cancer treatment, a new strategy has been proposed by combining multiple synergistic therapeutic modalities accessing different but inherently related targets and acting sequentially. A major benefit of this strategy is that the multi‐target mechanism could result in a cascade‐amplification effect leading to enhanced anticancer activity. In this review, we provide a critical discussion on the application of cascade‐amplification strategy in the treatment of various cancer indications, focusing on the rational combination of therapeutic agents and their mechanisms of action. A concise yet comprehensive analysis on the potential therapeutic benefit of this strategy was also included.

This article is categorized under:

Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease
Einleitung
Authors: Buß Imke
Published: April 2019

Die Hochschulen in Deutschland unterliegen in den letzten beiden Jahrzehnten starken Veränderungen. Diese Veränderungen wurden insbesondere durch den Bologna-Prozess angestoßen. Inhalt der Reformagenda ist dabei nicht nur die Implementierung von Bachelor- und Masterstudiengängen, sondern auch die Schaffung von Strukturen zur Vergleichbarkeit der Hochschulabschlüsse und der Vertrauensbildung in den Unterzeichnerstaaten der Bologna-Deklaration (Europäische Bildungsminister 1999, S. 5; Pietzonka 2013, S. 23 ff.).
Theoretische Hintergründe
Authors: Buß Imke
Published: April 2019

Die theoretischen Hintergründe dieser Arbeit lassen sich in vier Aspekte untergliedern (siehe Abbildung 1). Erstens wird das Konzept der strukturellen Studierbarkeit, welches in den Kapiteln 7 und 8 empirisch geprüft wird, entwickelt. Das Konzept analysiert insbesondere, welche Rolle die Studienstrukturen für die Studierbarkeit von Studiengängen spielen (Kapitel 2.1).
Die Umsetzung: Entscheidungsstrukturen und Anforderungen an Hochschulen
Authors: Buß Imke
Published: April 2019

Die vorangehenden Kapitel haben darauf fokussiert, was strukturelle Studierbarkeit ist und welche Anforderungen Studierende an die Struktur ihres Studiengangs stellen. Diese Ergebnisse sind jedoch nur dann für die Praxis hilfreich, wenn sie von der Politik und den Entscheidungsträgern in den Hochschulen rezipiert und umgesetzt werden können. In diesem Kapitel steht daher die Umsetzbarkeit der Konzepte im Mittelpunkt.
Study on contact fatigue of a wind turbine gear pair considering surface roughness
Authors: Liu Heli , Liu Huaiju , Zhu Caichao , Sun Zhangdong , Bai Houyi
Published: April 2019

Contact fatigue issues become more and more crucial in gear industry as they significantly affect the reliability and service life of associated mechanical systems such as wind turbine gearboxes. The contact fatigue behavior is mostly determined by the mechanical properties of materials and stress fields near the contact area, which is further influenced by the lubrication and surface roughness due to pressure fluctuations. In this study, a numerical model incorporating the lubrication state, tooth surface roughness, residual stress, and mechanical properties of the material is developed to determine the contact fatigue behavior of a megawatt level wind turbine carburized gear. The variations of the hardness and residual stress along the depth were characterized by the Vickers hardness measurement and X-ray diffraction test, respectively. The elastohydrodynamic lubrication theory was applied to predict the contact pressure distribution, highlighting the influence of the surface roughness that stemed from the original measurement through an optical profiler. The stress histories of the studied material points during a complete contact loading cycle were fast calculated using the discreteconcrete fast Fourier transformation (DC-FFT) method. Modified Dang Van diagrams under different working conditions were determined to estimate the contact fatigue failure risk. The effect of the root mean square (RMS) value of the surface roughness on the failure risk at critical material points were discussed in detail. Results revealed that the surface roughness significantly increases the contact fatigue failure risk within a shallow area, and the maximum risk appears near the surface.
Reinvestigating Cougar Mountain Cave: New Perspectives on Stratigraphy, Chronology, and a Younger Dryas Occupation in the Northern Great Basin
Authors: Rosencrance Richard L. , Smith Geoffrey M. , Jenkins Dennis L. , Connolly Thomas J. , Layton Thomas N.
Published: April 2019

Cougar Mountain Cave is located in Oregon's Fort Rock Basin. In 1958, avocationalist John Cowles excavated most of the cave's deposits and recovered abundant fiber, lithic, wood, and osseous artifacts. A crew from the University of California, Davis returned to the site in 1966 to evaluate the potential for further research, collecting additional lithic and fiber artifacts from disturbed deposits and in situ charcoal from apparently undisturbed deposits. Because Cowles took few notes or photographs, the Cougar Mountain Cave collection—most of which is housed at the Favell Museum in Klamath Falls, Oregon—has largely gone unstudied even though it contains diagnostic artifacts spanning the Holocene and, potentially, the terminal Pleistocene. We recently submitted charcoal and basketry from the site for radiocarbon dating, providing the first reliable sense of when Cougar Mountain Cave was first occupied. Our results indicate at least a Younger Dryas age for initial occupation. The directly dated basketry has provided new information about the age ranges and spatial distributions of diagnostic textile types in the northwestern Great Basin.
Cardiovascular daytime varying effect in cardiac surgery on surgical site infections and 1-year mortality: A prospective cohort study with 22,305 patients
Authors: Sommerstein Rami , Marschall Jonas , Kuster Stefan P. , Troillet Nicolas , Carrel Thierry , Eckstein Friedrich S. , Widmer Andreas F. ,   Swissnoso
Published: April 2019

Afternoon aortic valve replacement surgery may provide perioperative myocardial protection and improve patient outcomes compared with morning surgery. The results of our large observational study based on Swiss cardiac surgical site infection surveillance data suggest that the current evidence is insufficient to generally promote afternoon cardiac surgeries.
Theorists of Economic Nationalism in 1930s–1940s Romania
Authors: Ionescu Ştefan Cristian
Published: April 2019

This article examines the main theorists of economic nationalism (Romanianization) and their ideas promoting protectionism and anti-Semitism in 1930s–1940s Romania. Trying to offer a rational scientific justification for excluding foreigners, especially Jews, and increasing the role of ethnic Romanians in the economy, major scholars of economics offered solutions toward successful Romanianization. Because some of these economists were also influential politicians and public intellectuals, their investigations and blueprints for the project gained wide publicity and provided steps for achieving it rapidly and thoroughly. These economists disseminated their theoretical and empirical constructions of Romanianization in university courses, public lectures, and publications. Some were important scholars; among them, Virgil Madgearu, Mihail Manoilescu, Gheorghe N. Leon, Ion Răducanu, and D. R. Ioaniţescu, They examined Romanianization of the economy from the 1930s to the 1940s and influenced the agenda of local elites and the general public, due to their prestigious positions as politicians, public intellectuals, and professors at local universities.
Pour une nouvelle approche de la relation de crédit en histoire contemporaine
Authors: Lemercier Claire , Zalc Claire
Published: April 2019

La relation de crédit a encore été peu étudiée en histoire contemporaine, où elle est largement appréhendée sous le prisme d’un récit évolutionniste qui verrait la victoire progressive de « la rationalité économique »vial’institutionnalisation, la formalisation ou encore la modernisation, autant de notions qui semblent aller de soi. Nous proposons d’explorer les modalités de l’articulation entre formalisation et personnalisation de la relation de crédit, sans nous restreindre au schème de l’opposition entre les deux. En nous étayant sur une revue critique de la littérature récente sur ces thématiques, nous envisageons successivement la complémentarité des protagonistes du crédit et les transformations des instruments et des outils qui informent la transaction, avant d’aborder les accidents du crédit et les sanctions qui s’y attachent – ou non.
Le crédit à la consommation des classes populaires à la Belle Époque: Invention, innovation ou reconfiguration ?
Authors: Albert Anaïs
Published: April 2019

Durant la Belle Époque se construit en France une économie de la consommation de masse qui passe par l’accès massif au crédit des classes populaires. Ce phénomène ne peut pourtant se comprendre comme un simple changement d’échelle, car il s’agit d’un véritable réagencement de l’ordre social du crédit, de l’identification économique aux processus de sanction. Ces différentes facettes de la relation de crédit sont abordées successivement à travers deux dossiers documentaires : l’organisation du crédit à destination des classes populaires mise en place par les Grands Magasins parisiens Dufayel et les réformes introduites par la loi du 12 janvier 1895 sur la saisie-arrêt des salaires des ouvriers. La réorganisa- tion du système de crédit se traduit par l’apparition conjointe de nouvelles médiations et de nouvelles mises à distance, ainsi que par la multiplication des scènes sur lesquelles se joue la dette – entre espace commercial, tribunal et monde du travail.
Les faux-semblants de la « révolution du thé » (1920-1945) dans la province de Phú Thọ (Tonkin)
Authors: Tessier Olivier
Published: April 2019

Le leader lakota Sitting Bull a été enterré deux fois, à soixante ans d’intervalle, sur la réserve américaine de Standing Rock. Ses tombes n’invitent pas à écrire une nouvelle histoire de la mémoire d’un grand personnage mais à mettre au jour la production et la reproduction d’un pouvoir colonial certes fragile et contesté, mais aussi profondément inséré dans les interactions symboliques qui ont lieu sur et autour de la réserve. Elle veut relancer de cette manière l’histoire d’un colonialisme américain interne fait de privatisation des terres, d’individualisation des populations, et d’américanisation des esprits. Ce dernier volet a souvent été considéré comme un échec massif face à la résistance des peuples indiens. Le présent article veut nuancer et complexifier cette évaluation.
Blurred Lines: Social Media in Armed Conflict
Authors: Fisentzou Iphigenia
Published: April 2019

Technological advancements have revolutionised the social interactions of global society and in turn influenced the means and methods of warfare; increasing the involvement of civilians in hostilities, not only as victims but also as participants. Together with the involvement of multiple state and non-state actors, civilian participation makes these modern conflicts all the more unpredictable, challenging inter alia the traditional notion of direct participation in hostilities established under international law.
How Strong Is Influence of the Tropics and Midlatitudes on the Arctic Atmospheric Circulation and Climate Change?
Authors: Ye Kunhui , Jung Thomas
Published: April 2019

Relaxation experiments with the atmosphere model from European Centre for Medium‐range Weather Forecasts are analyzed to understand influence of lower latitudes (south of about 52 °N) on climate variability and change over the Arctic region. Interannual variability of the Arctic troposphere is impacted strongly by both the tropics and the midlatitudes. In general, the link in winter is stronger than that in summer. Furthermore, the tropics and midlatitudes have different preferred pathways by which they influence the Arctic. Trend analysis suggests that winter surface warming trends over the Arctic are driven strongly by the local sea ice‐atmospheric interaction. Warming at higher altitudes is strongly tied to remote non‐Arctic drivers, with some local amplification. Summer warming trends in northeastern Canada and Greenland are driven strongly by sea surface temperature/sea ice changes and partly by the tropics. The summer warming in northern Europe and western Russia is more strongly driven by the midlatitudes.
Ion Anisotropy in Earth's Magnetotail Current Sheet: Multicomponent Ion Population
Authors: Artemyev A. V. , Angelopoulos V. , Vasko I. Y. , Zhang X.‐J. , Runov A. , Zelenyi L. M.
Published: April 2019

The configuration and stability of the magnetotail current sheet, which determine the dynamics of the entire magnetosphere, largely depend on the ion kinetics as inferred from the velocity distribution function. This distribution is shaped by various transient acceleration processes and by contributions from the ionosphere and the distant magnetotail. Investigating the ion distribution is thus crucially important for adequate modeling of the current sheet stability. This necessitates spacecraft observations of the ion distribution in a wide energy range, from ionospheric outflow energies (below 1 keV) to high energies (approximately hundreds of kiloelectron volts). Using combined measurements of Electrostatic Analyzer and Solid State Telescope onboard Time History of Events and Macroscale Interactions during Substorms in 2008–2009 tail seasons, we demonstrate that the ion distribution in the quiet magnetotail current sheet (at times devoid of fast plasma flows and large electric fields) consists of three populations: a subthermal field‐aligned anisotropic population (contributing ∼90% to the total density but only ∼20% to the total pressure), an isotropic thermal population (contributing ∼10% of the total density and ∼60% of the total pressure), and a transversely anisotropic suprathermal population (contributing <1% of the total density and ∼20% of the total pressure). The suprathermal population may include high‐energy ions moving along transient (Speiser) orbits. The competing effects of subthermal and suprathermal partial pressure anisotropies result in an almost isotropic total (combined) ion pressure. We characterize the dependence of the ion distribution characteristics, including the anisotropy of different populations on local plasma sheet activity (ion flows and electric fields). We discuss the implications of our results for current sheet modelling.
Polar Cyclones at the Origin of the Reoccurrence of the Maud Rise Polynya in Austral Winter 2017
Authors: Francis Diana , Eayrs Clare , Cuesta Juan , Holland David
Published: April 2019

This study examines the role of atmospheric forcings in the occurrence of open‐ocean polynyas by investigating the case of the austral winter 2017's polynya located in the Lazarev Sea sector to the east of the Weddell Sea, known as the Maud Rise polynya or the Weddell Polynya. The ice‐free zone appeared in mid‐September 2017 and grew to as large as 80,000 km2 by the end of October 2017 before merging with the open ocean after the sea ice started to retreat at the beginning of the austral summer. Using a combination of satellite observations and reanalysis data at high spatiotemporal resolution, we found that severe cyclones, occurring over the ice pack, have a deterministic role in creating strong divergence in the sea ice field through strong cyclonic surface winds leading to the opening of the polynya. The occurrence of intense and frequent cyclones over the ice pack during austral winter 2017 was unusual, and it occurred under an enhanced strong positive meridional transport of heat flux and moisture toward Antarctica associated with an amplification of the atmospheric zonal wave 3 and a strong positive Southern Annular Mode index. We found that the opening of the polynya was not primarily due to direct ice melt by thermodynamic effects but rather to strong dynamical forcing by the winds on the sea ice, as in the case of coastal polynyas. Indeed, the meridional transport of heat toward Antarctica occurred over the Weddell Sea sector (i.e., to the east of the Lazarev Sea sector where the polynya is located) whereas the Lazarev Sea sector was under the influence of equatorward transport of cold air masses at that time. Our results show that the supply of warm and moist air coming from the west side of the South Atlantic Ocean into the Weddell Sea significantly increased the potential for cyclone formation as measured by the Eady growth rate leading to intense and frequent cyclogenesis over the ice pack, far south from the ice edge. After cyclogenesis in the Weddell Sea, these cyclones intensified as they moved eastward spinning over the Lazarev Sea with intensity comparable to category 11—violent storms—in the Beaufort scale. The cyclonic winds generated sea ice divergence by pushing the ice away from the cyclone center: To the east, north of it and to the west, south of it, which led to the reoccurrence of the Maud Rise polynya in mid‐September 2017.
Author Correction: Drug response in organoids generated from frozen primary tumor tissues
Authors: Walsh Alex J. , Cook Rebecca S. , Sanders Melinda E. , Arteaga Carlos L. , Skala Melissa C.
Published: April 2019

A correction has been published and is appended to both the HTML and PDF versions of this paper. The error has not been fixed in the paper.
A fast, reliable and sample-sparing method to identify fibre types of single muscle fibres
Authors: Christiansen Danny , MacInnis Martin J. , Zacharewicz Evelyn , Xu Hongyang , Frankish Barnaby P. , Murphy Robyn M.
Published: April 2019

Many skeletal muscle proteins are present in a cell-specific or fibre-type dependent manner. Stimuli such as exercise, aging, and disease have been reported to result in fibre-specific responses in protein abundances. Thus, fibre-type-specific determination of the content of specific proteins provides enhanced mechanistic understanding of muscle physiology and biochemistry compared with typically performed whole-muscle homogenate analyses. This analysis, however, is laborious and typically not performed. We present a novel dot blotting method for easy and rapid determination of skeletal muscle fibre type based on myosin heavy chain (MHC) isoform presence. Requiring only small amounts of starting muscle tissue (i.e., 2–10 mg wet weight), muscle fibre type is determined in one-tenth of a 1–3-mm fibre segment, with the remainder of each segment pooled with fibre segments of the same type (I or II) for subsequent protein quantification by western blotting. This method, which we validated using standard western blotting, is much simpler and cheaper than previous methods and is adaptable for laboratories routinely performing biochemical analyses. Use of dot blotting for fibre typing will facilitate investigations of fibre-specific responses to diverse stimuli, which will advance our understanding of skeletal muscle physiology and biochemistry.
High-Efficiency Visible Light Manipulation Using Dielectric Metasurfaces
Authors: Aoni Rifat Ahmmed , Rahmani Mohsen , Xu Lei , Zangeneh Kamali Khosro , Komar Andrei , Yan Jingshi , Neshev Dragomir , Miroshnichenko Andrey E.
Published: April 2019

The development of a miniaturised device that provides efficient beam manipulation with high transmittance is extremely desirable for the broad range of applications including holography, metalens, and imaging. Recently, the potential of dielectric metasurfaces has been unleashed to efficiently manipulate the beam with full 2π-phase control by overlapping the electric and magnetic dipole resonances. However, in the visible range for available materials, it comes with the price of higher absorption that reduces efficiency. Here, we have considered dielectric amorphous silicon (a-Si) nanodisk and engineered them in such a way which provides minimal absorption loss in the visible range. We have experimentally demonstrated meta-deflector with high transmittance which operates in the visible wavelengths. The supercell of proposed meta-deflector consists of 15 amorphous silicon nanodisks numerically shows the transmission efficiency of 95% and deflection efficiency of 95% at operating wavelength of 715 nm. However, experimentally measured transmission and deflection efficiencies are 83% and 71%, respectively, having the experimental deflection angle of 8.40°. Nevertheless, by reducing the supercell length, the deflection angle can be controlled, and the value 15.50° was experimentally achieved using eight disks supercell. Our results suggest a new way to realise the highly transmittance metadevice with full 2π-phase control operating with the visible light which could be applicable in the imaging, metalens, holography, and display applications.
Lensing in the Ultrasonic Domain using Negative Refraction Induced by Material Contrast
Authors: Manjunath C. T. , Rajagopal Prabhu
Published: April 2019

The focusing of ultrasound using topographic lenses, typically made of plates with step changes that cause an interaction between forward- and backward-propagating guided waves, has been widely studied in recent years. However, such ‘step-change’ lenses require precise machining and moreover, the thick-thin structure can be unstable during deployment in practical inspection applications. The work reported here follows from the insight that perhaps any approach to induce a mismatch in acoustical impedance as achieved by the step-change can also lead to focusing of ultrasonic guided waves. By carefully choosing the impedance pairing, a novel material contrast lens stacking Aluminium and Molybdenum plates in series is shown to achieve focusing of ultrasound through negative refraction. The interface between the two metals causes the interaction of the forward-propagating second symmetric Lamb mode S2 into the backward- propagating first symmetric S2b. The focusing of Lamb waves is demonstrated using numerical simulations validated by experiments. Comparison with a simple Aluminium-Aluminium plate combination brings out the underlying physics of focusing using the proposed material contrast lens. Simulation results showing super-resolution imaging using the proposed material contrast lens  are also presented, demonstrating the power of the proposed approach. This report opens up the possibilities of developing new lensing devices for use in medical imaging and nondestructive evaluation, among other possible applications.
The effect of anaerobic digestate derived composts on the metabolite composition and thermal behaviour of rosemary
Authors: Bustamante M. A. , Nogués I. , Jones S. , Allison G. G.
Published: April 2019

The study reports on the effect of anaerobic digestate derived composts on the metabolite composition and thermal behaviour of rosemary (Rosmarinus officinalis L.). Plants were cultivated in semiarid soil under four different fertiliser treatments (composts of anaerobic digested cattle (C) or pig slurry (P) at 30t/ha and 60 t/ha, and two control treatments (inorganic fertiliser and no fertiliser application). Samples of leaves and stems were analysed to investigate the effect of treatment on chemical composition and thermochemical properties. Three orthogonal analytical approaches were used, namely: Fourier transform mid infrared spectroscopy (FTIR), gas chromatography/mass spectrometry (GC/MS) and thermochemical gravimetric analysis (TGA). FTIR and GC/MS showed fertiliser treatment resulted in tissue specific changes in sample metabolite composition. Fertiliser treatment was detected to change the thermogravimetric properties of the leaf samples and from inorganic and composted pig slurry digestate treatments had greater ash content and lower proportions of fixed carbon compared with samples from the unfertilised control treatment. This study provides information on how the composition of rosemary might be altered by fertiliser application in regions of poor soil, and has implications for biomass quality when rosemary is grown on semi-wild sites for the purpose of soil improvement.
Isolation, Purification, and Characterization of Heparinase from Streptomyces variabilis MTCC 12266
Authors: Singh Vineeta , Haque Shafiul , Kumari Vibha , El-Enshasy Hesham A. , Mishra B. N. , Somvanshi Pallavi , Tripathi C. K. M.
Published: April 2019

Arterial/venous thrombosis is the major cardiovascular disorder accountable for substantial mortality; and the current demand for antithrombotic agents is extensive. Heparinases depolymerize unfractionated heparin (UFH) for the production of low molecular-weight heparins (LMWHs; used as anticoagulants against thrombosis). A microbial strain of Streptomyces sp. showing antithrombotic activity was isolated from the soil sample collected from north India. The strain was characterized by using 16S rRNA homology technique and identified as Streptomyces variabilis MTCC 12266 capable of producing heparinase enzyme. This is the very first communication reporting Streptomyces genus as the producer of heparinase. It was observed that the production of intracellular heparinase was [63.8 U/mg protein (specific activity)] 1.58 folds higher compared to extracellular heparinase [40.28 U/mg protein]. DEAE-Sephadex A-50 column followed by Sepharose-6B column purification of the crude protein resulted 19.18 folds purified heparinase. SDS-PAGE analysis of heparinase resulted an estimated molecular-weight of 42 kDa. It was also found that intracellular heparinase has the ability to depolymerize heparin to generate LMWHs. Further studies related to the mechanistic action, structural details, and genomics involved in heparinase production from Streptomyces variabilis are warranted for large scale production/purification optimization of heparinase for antithrombotic applications.
Fragment-based screening identifies inhibitors of ATPase activity and of hexamer formation of Cagα from the Helicobacter pylori type IV secretion system
Authors: Arya Tarun , Oudouhou Flore , Casu Bastien , Bessette Benoit , Sygusch Jurgen , Baron Christian
Published: April 2019

Type IV secretion systems are multiprotein complexes that mediate the translocation of macromolecules across the bacterial cell envelope. In Helicobacter pylori a type IV secretion system encoded by the cag pathogenicity island encodes 27 proteins and most are essential for virulence. We here present the identification and characterization of inhibitors of Cagα, a hexameric ATPase and member of the family of VirB11-like proteins that is essential for translocation of the CagA cytotoxin into mammalian cells. We conducted fragment-based screening using a differential scanning fluorimetry assay and identified 16 molecules that stabilize the protein suggesting that they bind Cagα. Several molecules affect binding of ADP and four of them inhibit the ATPase activity. Analysis of enzyme kinetics suggests that their mode of action is non-competitive, suggesting that they do not bind to the active site. Cross-linking suggests that the active molecules change protein conformation and gel filtration and transmission electron microscopy show that molecule 1G2 dissociates the Cagα hexamer. Addition of the molecule 1G2 inhibits the induction of interleukin-8 production in gastric cancer cells after co-incubation with H. pylori suggesting that it inhibits Cagα in vivo. Our results reveal a novel mechanism for the inhibition of the ATPase activity of VirB11-like proteins.
Amyloid β-dependent mitochondrial toxicity in mouse microglia requires P2X7 receptor expression and is prevented by nimodipine
Authors: Chiozzi Paola , Sarti Alba Clara , Sanz Juana M. , Giuliani Anna Lisa , Adinolfi Elena , Vultaggio-Poma Valentina , Falzoni Simonetta , Di Virgilio Francesco
Published: April 2019

Previous data from our laboratory show that expression of the P2X7 receptor (P2X7R) is needed for amyloid β (Aβ)-stimulated microglia activation and IL-1β releasein vitroandin vivo. We also showed that Aβ-dependent stimulation is inhibited by the dihydropyridine nimodipine at an intracellular site distal to the P2X7R. In the present study, we used the N13 microglia cell line and mouse primary microglia from wt andP2rx7-deleted mice to test the effect of nimodipine on amyloid β (Aβ)-dependent NLRP3 inflammasome expression and function, and on mitochondrial energy metabolism. Our data show that in microglia Aβ causes P2X7R-dependent a) NFκB activation; b) NLRP3 inflammasome expression and function; c) mitochondria toxicity; and these changes are fully inhibited by nimodipine. Our study shows that nimodipine is a powerful blocker of cell damage caused by monomeric and oligomeric Aβ, points to the mitochondria as a crucial target, and underlines the permissive role of the P2X7R.
Neprilysin Inhibitor–Angiotensin II Receptor Blocker Combination Therapy (Sacubitril/valsartan) Suppresses Atherosclerotic Plaque Formation and Inhibits Inflammation in Apolipoprotein E- Deficient Mice
Authors: Zhang Hui , Liu Gangqiong , Zhou Wenping , Zhang Wenjing , Wang Kai , Zhang Jinying
Published: April 2019

We assessed the effects of the sacubitril/valsartan combination drug (LCZ696), in comparison to valsartan alone, on the progression of atherosclerotic plaque formation and inflammatory gene expression in apolipoprotein E- deficient mice (apoE−/− mice). Seventy-two apoE−/− mice were fed a western diet and a constrictive silastic tube was used to elicit carotid lesion formation. The animals were separated into a control group, a valsartan group or an LCZ696 group (n = 24 in each group). Plaques in the carotid artery were harvested 12 weeks later for histological examination. The levels of pro-inflammatory genes in the plasma and lesions were detected using real-time PCR and ELISA. Valsartan or LCZ696 treatment remarkably inhibited the expression of pro-inflammatory genes, including interleukin-6, matrix metalloproteinase-8 and monocyte chemotactic protein-1, in comparison with the control group. Meanwhile, both valsartan and LCZ696 suppressed the formation of atherosclerotic plaques by decreasing plaque lipid content and cross-sectional plaque area and increasing the content of plaque collagen and fibrous cap thickness. In particular, LCZ696 performed the best in suppressing atherosclerosis and inhibiting the level of pro-inflammatory genes. LCZ696 significantly ameliorated atherosclerosis and inflammation in apoE−/− mice compared with valsartan.
OVOL2 induces mesenchymal-to-epithelial transition in fibroblasts and enhances cell-state reprogramming towards epithelial lineages
Authors: Watanabe Kazuhide , Liu Ye , Noguchi Shuhei , Murray Madeleine , Chang Jen-Chien , Kishima Mami , Nishimura Hajime , Hashimoto Kosuke , Minoda Aki , Suzuki Harukazu
Published: April 2019

Mesenchymal-to-epithelial transition (MET) is an important step in cell reprogramming from fibroblasts (a cell type frequently used for this purpose) to various epithelial cell types. However, the mechanism underlying MET induction in fibroblasts remains to be understood. The present study aimed to identify the transcription factors (TFs) that efficiently induce MET in dermal fibroblasts. OVOL2 was identified as a potent inducer of key epithelial genes, and OVOL2 cooperatively enhanced MET induced by HNF1A, TP63, and KLF4, which are known reprogramming TFs to epithelial lineages. In TP63/KLF4-induced keratinocyte-like cell-state reprogramming, OVOL2 greatly facilitated the activation of epithelial and keratinocyte-specific genes. This was accompanied by enhanced changes in chromatin accessibility across the genome. Mechanistically, motif enrichment analysis revealed that the target loci of KLF4 and TP63 become accessible upon induction of TFs, whereas the OVOL2 target loci become inaccessible. This indicates that KLF4 and TP63 positively regulate keratinocyte-associated genes whereas OVOL2 suppresses fibroblast-associated genes. The exogenous expression of OVOL2 therefore disrupts fibroblast lineage identity and facilitates fibroblast cell reprogramming into epithelial lineages cooperatively with tissue-specific reprogramming factors. Identification of OVOL2 as an MET inducer and an epithelial reprogramming enhancer in fibroblasts provides new insights into cellular reprogramming improvement for future applications.
Dark-field microscopy for characterization of single molecule dynamicsin vitroandin vivo
Authors: Wang Bingquan , Sun Dan , Zhang Ce , Wang Kaige , Bai Jintao
Published: April 2019

Dark-field microscopy directly detects scattered light from a sample, and therefore requires no fluorescent labeling for single molecule detection.
Active site labeling of fatty acid and polyketide acyl-carrier protein transacylases
Authors: Davis Tony D. , Michaud Jennifer M. , Burkart Michael D.
Published: April 2019

Fluorescent probe design and site-directed mutagenesis unveil new activity-based chemical reporters for fatty acid and polyketide synthase acyl-carrier protein transacylases.
Nitrogen/oxygen co-doped mesoporous carbon octahedrons for high-performance potassium-ion batteries
Authors: Xia Guoliang , Wang Changlai , Jiang Peng , Lu Jian , Diao Jiefeng , Chen Qianwang
Published: April 2019

As an anode for KIBs, the MCO electrode shows an ultralong cycle life and maintains a reversible capacity of 80 mA h g−1.
Recent advances in reaction-based fluorescent probes for detecting monoamine oxidases in living systems
Authors: Huang Jintao , Hong Danqi , Lang Wenjie , Liu Jian , Dong Jia , Yuan Chaonan , Luo Jie , Ge Jingyan , Zhu Qing
Published: April 2019

This Minireview summarizes the recent advances in reaction based MAO type fluorescent probes and their imaging applications in living systems.
A new approach for the achievement of stable aqueous dispersions of carbon nanotubes
Authors: Damasceno João Paulo V. , Zarbin Aldo J. G.
Published: April 2019

A simple and innovative way to achieve highly stable aqueous dispersions of both multi- and single-walled carbon nanotubes is reported.
Synthesis of hydrosilanes via Lewis-base-catalysed reduction of alkoxy silanes with NaBH4
Authors: Aoyagi Keiya , Ohmori Yu , Inomata Koya , Matsumoto Kazuhiro , Shimada Shigeru , Sato Kazuhiko , Nakajima Yumiko
Published: April 2019

Hydrosilanes were synthesized by reduction of alkoxysilanes with BH3 in the presence of hexamethylphosphoric triamide (HMPA) as a Lewis-base catalyst. The reaction was also achieved using an inexpensive and easy-to-handle handled hydride source NaBH4, which reacted with EtBr as a sacrificial reagent to form BH3in situ.
1 : 2 charge-transfer complexes of perylene and coronene with perylene diimide, and the ambipolar transistors
Authors: Sato Ryonosuke , Yoo Dongho , Mori Takehiko
Published: April 2019

The title 1 : 2 charge-transfer complexes have DAA-type mixed stacks and show electron-dominant ambipolar transistor properties.
Similar chemical structures, dissimilar triplet quantum yields: a CASPT2 model rationalizing the trend of triplet quantum yields in nitroaromatic systems
Authors: Giussani Angelo , Worth Graham A.
Published: April 2019

S1/S0 accessibility strongly influences the triplet quantum yields of nitronaphthalenes.
A strategy to convert propane to aromatics (BTX) using TiNp4 grafted at the periphery of ZSM-5 by surface organometallic chemistry
Authors: Al Maksoud Walid , Gevers Lieven E. , Vittenet Jullian , Ould-Chikh Samy , Telalovic Selvedin , Bhatte Kushal , Abou-Hamad Edy , Anjum Dalaver H. , Hedhili Mohamed N. , Vishwanath Vinu , Alhazmi Abdulrahman , Almusaiteer Khaled , Basset Jean Marie
Published: April 2019

The direct conversion of propane into aromatics (BTX) using modified ZSM-5 was achieved with a strategy of “catalysis by design”.
A highly conductive nanostructured PEDOT polymer confined into the mesoporous MIL-100(Fe)
Authors: Salcedo-Abraira Pablo , Santiago-Portillo Andrea , Atienzar Pedro , Bordet Pierre , Salles Fabrice , Guillou Nathalie , Elkaim Erik , Garcia Hermenegildo , Navalon Sergio , Horcajada Patricia
Published: April 2019

A novel nanostructured conducting polymer@MOF composite has demonstrated an enhanced conductivity and a reversible and cyclable electrochromic switching.
Correction: Isopolymolybdate-based inorganic–organic hybrid compounds constructed by multidentate N-donor ligands: syntheses, structures and properties
Authors: Guo Haiyang , Gong Chunhua , Zeng Xianghua , Xu Hao , Zeng Qingdao , Zhang Junyong , Xie Jingli
Published: April 2019

Correction for ‘Isopolymolybdate-based inorganic–organic hybrid compounds constructed by multidentate N-donor ligands: syntheses, structures and properties’ by Haiyang Guo et al., Dalton Trans., 2019, DOI: 10.1039/c9dt00119k.
A facile method for hydroxytrifluoromethylation of alkenes with Langlois reagent and DMSO
Authors: Shen Wei-Guo , Wu Qing-Yan , Gong Xing-Yu , Ao Gui-Zhen , Liu Feng
Published: April 2019

A simple and mild protocol is developed for the synthesis of β-trifluoromethyl alcohols from alkenes.
Gecko toe pads inspired in situ switchable superhydrophobic shape memory adhesive film
Authors: Wang Yongzhen , Lai Hua , Cheng Zhongjun , Zhang Haiyang , Zhang Enshuang , Lv Tong , Liu Yuyan , Jiang Lei
Published: April 2019

A gecko toe pad inspired superhydrophobic shape memory adhesive film that can realize in situ and step-by-step release of multi-droplets.