bluuebunny/crossref_metadata_2025 huggingface dataset:
Radar sounder evidence of thick, porous sediments in Meridiani Planum and implications for ice‐filled deposits on Mars
Authors: Watters Thomas R. , Leuschen Carl J. , Campbell Bruce A. , Morgan Gareth A. , Cicchetti Andrea , Grant John A. , Phillips Roger J. , Plaut Jeffrey J.
Published: September 2017

Meridiani Planum is one of the most intensely studied regions on Mars, yet little is known about the physical properties of the deposits below those examined by the Opportunity rover. We report the detection of subsurface echoes within the Meridiani Planum deposits from data obtained by the Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) instrument. The delay time between the surface and subsurface returns is indicative of materials with a real dielectric constant of 3.6 ± 0.6. The real dielectric constant is strongly modulated by bulk density. Newly derived compaction relationships for Mars indicate that the relatively low dielectric constant of the Meridiani Planum deposits is consistent with a thick layer of ice‐free, porous, basaltic sand. The unique physiographic and hydrologic setting of Meridiani Planum may have provided an ideal sediment trap for eolian sands. The relatively low gravity and the cold, dry climate that has dominated Mars for billions of years may have allowed thick eolian sand deposits to remain porous and only weakly indurated. Minimally compacted sedimentary deposits may offer a possible explanation for other nonpolar region units with low apparent bulk dielectric constants.
A Madden‐Julian Oscillation event remotely accelerates ocean upwelling to abruptly terminate the 1997/1998 super El Niño
Authors: Miyakawa T. , Yashiro H. , Suzuki T. , Tatebe H. , Satoh M.
Published: September 2017

The termination of the superintense 1997/1998 El Niño was extraordinarily abrupt. The May 1998 Madden‐Julian Oscillation (MJO), a massive complex of stormy tropical clouds, is among possible contributors to the abrupt termination. Despite having been sensationally proposed 18 years ago, the role of the MJO remained controversial and speculative because of the difficulty of sufficiently simulating the El Niño and MJO simultaneously. An ensemble simulation series using a newly developed, fully ocean‐coupled version of a global cloud system resolving numerical model replicated the specific atmosphere and ocean conditions of May 1998 in unprecedented detail, extending the prediction skill of the MJO to 46 days. Simulation ensemble members with stronger MJO activities over the Maritime Continent experienced quicker sea surface temperature drop in the eastern Pacific, confirming that the easterly winds associated with the remote MJO accelerated ocean upwelling to abruptly terminate the El Niño.
Photophysical and Structural Properties of Rare‐Earth Phenolate Compounds
Authors: Teotonio Ercules E. S. , Rodrigues Lucas C. V. , Brito Hermi F. , Felinto Maria Claudia F. C. , Malta Oscar M. L.
Published: September 2017

Trivalent rare‐earth (RE3+) phenolate complexes have been receiving growing attention owing to their remarkable structural, luminescent, and magnetic properties. The RE3+ions play an important role in the synthetic mechanisms acting as template, leading to a large number of homodinuclear and heterodinuclear coordination compounds presenting macrocyclic and macroacyclic phenolate ligands. The photoluminescent behavior of these kinds of complexes has been attributed to an efficient intramolecular energy transfer from the ligands to the RE3+ions. The RE phenolate complexes have opened new possibilities for practical applications such as in RE3+separation, in tunable photonic devices, in fluoroimmunoassays, and as paramagnetic contrast agents in magnetic resonance imaging.
Comparative Structures of Specialised Monocotyledonous Leaf Blade Plasmodesmata
Authors: Botha C.E.J. , Cross R.H.M. , Liu L.
Published: September 2017

The sections in this article are

Introduction

Maturity‐Related Changes in Plasmodesmatal Structure

The Plasmodesmatal Cell Wall Interfaces in Monocot Leaves

Plasmodesmata Crossing the Suberin Lamella – Constrictions and Asymmetry

Regulation at the Neck – Structural Considerations

Changes in Wall Structure and Plasmodesmatal Form – Secondary Modification
Plasmodesmata and Plant Morphogenesis
Authors: Kobayashi Ken , Kim Insoon , Cho Euna , Zambryski Patricia
Published: September 2017

The sections in this article are

Introduction

Role ofPDand Symplasmic Domain Boundaries during Plant Development

Generic Changes in Structure and Function ofPDduring Different Developmental Processes

Changes inPDConductivity during Vegetative Development

Changes inPDConductivity during Floral Induction

Changes inPDConductivity during Embryogenesis

Importance of Intercellular Communication: Roles of Transported Macromolecules in Plant Development

Concluding Remarks

Acknowledgements
Virus‐Induced Gene Silencing
Authors: Dalmay Tamas
Published: September 2017

The sections in this article are

Introduction

Virus‐Induced Gene Silencing

Viral Suppressors of Gene Silencing

Acknowledgement
Professional Development and Professionalization in the Field of Adult Basic Education
Authors: Smith Cristine
Published: September 2017

This chapter offers an update on efforts to provide all adult basic education teachers with access to high‐quality professional development.
Mechanical Properties of a Novel Zero Poisson's Ratio Honeycomb
Authors: Chen Yu , Fu Ming‐Hui
Published: September 2017

In this paper, a novel honeycomb is proposed by embedding a rib into every cell of the existing zero Poisson's ratio (ZPR) configuration, semi re‐entrant honeycomb (SRH). Analytical model is developed to investigate the in‐plane mechanical properties of the new honeycomb, and the resulting theoretical expressions are compared with the experimental tests and numerical results obtained from two different finite element (FE) models (3D beam model and 3D solid model), leading to a good correlation. FE analysis, analytical modeling, and experimental tests of the new honeycomb show that it can achieve ZPR effect in two principal directions. For further studies, parameters analyses are carried out to explore the dependence of the in‐plane mechanical properties versus the geometric parameters. The results show that bending is the dominated deformation model when the new honeycomb is compressed along the x‐ direction, while stretch controlled in the y‐ directional compression. It is remarkable that the new proposed honeycomb features superior specific stiffness and more flexible in mechanical properties tailoring compared to the other ZPR honeycombs in the literature. Given these benefits, the new honeycomb may be promising in some practical applications.
ZnO Coated Anodic 1D TiO2 Nanotube Layers: Efficient Photo‐Electrochemical and Gas Sensing Heterojunction
Authors: Ng Siowwoon , Kuberský Petr , Krbal Milos , Prikryl Jan , Gärtnerová Viera , Moravcová Daniela , Sopha Hanna , Zazpe Raul , Yam Fong Kwong , Jäger Aleš , Hromádko Luděk , Beneš Ludvík , Hamáček Aleš , Macak Jan M.
Published: September 2017

The authors demonstrate, in this work, a fascinating synergism of a high surface area heterojunction between TiO2 in the form of ordered 1D anodic nanotube layers of a high aspect ratio and ZnO coatings of different thicknesses, produced by atomic layer deposition. The ZnO coatings effectively passivate the defects within the TiO2 nanotube walls and significantly improve their charge carrier separation. Upon the ultraviolet and visible light irradiation, with an increase of the ZnO coating thickness from 0.19 to 19 nm and an increase of the external potential from 0.4–2 V, yields up to 8‐fold enhancement of the photocurrent density. This enhancement translates into extremely high incident photon to current conversion efficiency of ≈95%, which is among the highest values reported in the literature for TiO2 based nanostructures. In addition, the photoactive region is expanded to a broader range close to the visible spectral region, compared to the uncoated nanotube layers. Synergistic effect arising from ZnO coated TiO2 nanotube layers also yields an improved ethanol sensing response, almost 11‐fold compared to the uncoated nanotube layers. The design of the high‐area 1D heterojunction, presented here, opens pathways for the light‐ and gas‐assisted applications in photocatalysis, water splitting, sensors, and so on.
Strategies for Drug Encapsulation and Controlled Delivery Based on Vapor‐Phase Deposited Thin Films
Authors: Perrotta Alberto , Werzer Oliver , Coclite Anna Maria
Published: September 2017

Vapor‐phase deposition methods allow the synthesis and engineering of organic and inorganic thin films, with high control on the chemical composition, physical properties, and conformality. In this review, the recent applications of vapor‐phase deposition methods such as initiated chemical vapor deposition (iCVD), plasma enhanced chemical vapor deposition (PE‐CVD), and atomic layer deposition (ALD), for the encapsulation of active pharmaceutical drugs are reported. The strategies and emergent routes for the application of vapor‐deposited thin films on the drug controlled release and for the engineering of advanced release nanostructured devices are presented.
Asymmetric Hydrolytic and Aminolytic Kinetic Resolution of Racemic Epoxides using Recyclable Macrocyclic Chiral Cobalt(III) Salen Complexes
Authors: Tak Rajkumar , Kumar Manish , Menapara Tusharkumar , Gupta Naveen , Kureshy Rukhsana I. , Khan Noor‐ul H. , Suresh E.
Published: September 2017

New chiral macrocyclic cobalt(III) salen complexes were synthesized and used as catalyst for the asymmetric kinetic resolution (AKR) of terminal epoxides and glycidyl ethers with aromatic/aliphatic amines and water as nucleophiles. This is the first occasion where a Co(III) salen complex demonstrated its ability to catalyze AKR as well as hydrolytic kinetic resolution (HKR) reactions. Excellent enantiomeric excesses of the epoxides, the corresponding amino alcohols and diols (upto 99%) with quantitative yields were achieved by using the chiral Co(III) salen complexes in dichloromethane at room temperature. This protocol was further extended for the synthesis of two important drug molecules, i.e., (S)‐propranolol and (R)‐naftopidil. The catalytic system was also explored for the synthesis of chirally pure diols and chiral cyclic carbonates using carbon dioxide as a greener renewable C1 source. The catalyst was recycled for upto 5 catalytic cycles with retention of enantioselectivity.

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Dehydration‐type Ti‐Claisen Condensation (Carbonhomologation) of α‐Heteroatom‐substituted Acetates with Alkyl Formates: Utilization as (Z)‐Stereodefined Cross‐coupling Partners and Application to Concise Synthesis of Strobilurin A
Authors: Nakatsuji Hidefumi , Kamada Risa , Kitaguchi Hideya , Tanabe Yoo
Published: September 2017

TiCl4−Et3N or −Bu3N reagent conducted a highly (Z)‐stereoselective carbon homologation (dehydration type Ti‐Claisen condensation) of alkyl α‐heteroatom (halo and sulfonyloxy)‐substituted acetates (XCH2CO2R) with alkyl formates (HCO2R) to afford various alkyl β‐alkoxy‐α‐halo or sulfonyloxy‐substituted acrylates (24 examples; 51%–91% yield). Stereoretentive Suzuki‐Miyaura, Negishi, and Sonogashira cross‐couplings using the obtained methyl β‐methoxy‐α‐halo or sulfonyloxy‐substituted acrylates proceeded smoothly to produce a variety of β‐alkoxy‐α‐substituted acrylates in moderate to high yield (35 examples; 29%–99% yield). As a successful application, a 3‐step straightforward synthesis of strobilurin A was performed utilizing the present reaction sequence (dehydration type Ti‐Claisen condensation and Suzuki‐Miyaura cross‐coupling), wherein the geometry of the three consecutive olefins (2E,3Z,5E) was completely maintained.

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Long‐term impact of postoperative pneumonia after curative gastrectomy for elderly gastric cancer patients
Authors: Suzuki Satoshi , Kanaji Shingo , Matsuda Yoshiko , Yamamoto Masashi , Hasegawa Hiroshi , Yamashita Kimihiro , Oshikiri Taro , Matsuda Takeru , Sumi Yasuo , Nakamura Tetsu , Kakeji Yoshihiro
Published: September 2017

With the extension of life expectancy, cancer has been increasing in elderly populations. Postoperative pneumonia can negatively influence immediate mortality following gastrectomy for elderly patients, but its impact on long‐term survival remains unclear. We retrospectively reviewed the cases of patients aged ≥75 years who underwent curative gastrectomy for gastric cancer from 2000 to 2014 to determine the long‐term effects of postoperative pneumonia and to identify independent risk factors along with physical status and surgical procedure. Of 250 patients, 32 (12.8%) developed postoperative pneumonia. Patients with postoperative pneumonia had significantly worse overall survival (OS) than those without postoperative pneumonia (P<.001). A multivariate analysis identified postoperative pneumonia as a prognostic factor for OS (hazard ratio, 2.06; 95% CI, 1.05‐3.75; P=.036). Significant risk factors for the development of postoperative pneumonia were male gender (P=.026) and D2 lymphadenectomy (P<.001). D2 lymphadenectomy was associated with poorer OS than D1 or D1+lymphadenectomy in patients with an American Society of Anesthesiologists (ASA) score 3 (P=.026), but did not influence OS negatively in patients with an ASA score ≤2. Limited lymphadenectomy did not affect the cancer‐specific survival of elderly patients with ASA score 3. Postoperative pneumonia following gastrectomy has an adverse impact on the long‐term survival of elderly gastric cancer patients. A limited lymphadenectomy during curative resection should be considered to prevent postoperative pneumonia in frail elderly patients with ASA score 3. Postoperative pneumonia following gastrectomy has an adverse impact on the long‐term survival of elderly gastric cancer patients. Extent of lymph node dissection during curative resection should be limited to prevent postoperative pneumonia, based on the patient's frailty.
Incidence and predictive score for delayed hemolytic transfusion reaction in adult patients with sickle cell disease
Authors: Narbey David , Habibi Anoosha , Chadebech Philippe , Mekontso‐Dessap Armand , Khellaf Mehdi , Lelièvre Jean‐Daniel , Godeau Bertrand , Michel Marc , Galactéros Frédéric , Djoudi Rachid , Bartolucci Pablo , Pirenne France
Published: September 2017

Delayed hemolytic transfusion reaction (DHTR) is a life‐threatening complication of transfusion in sickle cell disease (SCD). The frequency of DHTR is underestimated because its symptoms mimic those of vaso‐occlusive crisis and antibodies (Abs) are often not detectable. No predictive factors for identifying patients likely to develop DHTR have yet been defined. We conducted a prospective single‐center observational study over 30 months in adult sickle cell patients. We included 694 transfusion episodes (TEs) in 311 patients, divided into occasional TEs (OTEs: 360) and chronic transfusion program (CTEs: 334). During follow‐up, 15 cases of DHTR were recorded, exclusively after OTEs. DHTR incidence was 4.2% per OTE (95% CI [2.6; 6.9]) and 6.8% per patient during the 30 months of the study (95% CI [4.2; 11.3]). We studied 11 additional DHTR cases, to construct a predictive score for DHTR. The DHTR mortality is high, 3 (11.5%) of the 26 DHTR patients died. The variables retained in the multivariate model were history of DHTR, number of units previously transfused and immunization status before transfusion. The resulting DHTR‐predictive score had an area under the ROC curve of 0.850 [95% CI: 0.780‐0.930], a negative‐predictive value of 98.4% and a positive‐predictive value of 50%. We report in our study population, for the first time, the incidence of DHTR, and, its occurrence exclusively in occasionally transfused patients. We also describe a simple score for predicting DHTR in patients undergoing occasional transfusion, to facilitate the management of blood transfusion in SCD patients.
A molar microwear texture analysis of pitheciid primates
Authors: Ragni Anna J. , Teaford Mark F. , Ungar Peter S.
Published: September 2017

Dental microwear textures have been examined for a broad range of extant primates to assess their efficacy for reconstructing diets of fossil species. To date though, no dental microwear texture data have been published for pitheciid molars, despite reported variation in degree of sclerocarpy and, by extension, the fracture properties of foods these platyrrhines eat. While all pitheciids eat hard or tough seeds, Chiropotes and Pithecia have been documented to consume more than Callicebus. In this study, we explored whether measures of molar microwear texture complexity discriminate taxa following variation in reliance upon seeds, and whether dispersion among variables is greatest in Callicebus, which has the most variable diet. Here we report results for a study of microwear textures on M2 “Phase II” facets of Ch. satanas (N = 14), P. irrorata (N = 8), and Ca. moloch (N = 24) from the Brazilian Amazon (Oriximina, UHE Samuel, and Taperinha, respectively). Textures examined using a scanning confocal profiler showed significant differences in central tendencies for three measures: mean dale area (Sda), anisotropy (Str), and heterogeneity (HAsfc9). Ten measures showed significant differences in dispersion, with Callicebus being significantly more variable in eight of those ten. These results demonstrate that the pitheciids with different morphological adaptations and dietary reliance on seeds differ in their dental microwear textures, though less than initially hypothesized. Measures of dispersion, especially, show potential for identifying dietary variability.
Solution Structure and Reactivity with Metallocenes of AlMe2F: Mimicking Cation–Anion Interactions in Metallocenium–Methylalumoxane Inner‐Sphere Ion Pairs
Authors: Oliva Leone , Oliva Patrizia , Galdi Nunzia , Pellecchia Claudio , Sian Leonardo , Macchioni Alceo , Zuccaccia Cristiano
Published: September 2017

The solution structure of AlMe2F and its reactivity with a prototypical ansa‐metallocene have been investigated by advanced NMR techniques, in an attempt to indirectly shed some light on the structure and working principles of methylalumoxane (MAO) mixtures in olefin polymerization. In solution, AlMe2F gives rise to a complex equilibrium of oligomeric species, including a heterocubane [(Me2Al)4F4] tetramer, resembling the behavior of MAO. This complex mixture reacts with (ETH)ZrMe2 (ETH=rac‐[ethylenebis(4,5,6,7‐tetrahydro‐1‐indenyl)]) to afford [(ETH)ZrMeδ+(μ‐F)(AlMe2F)nAlMe3δ−] inner‐sphere ion pairs through successive insertions/deinsertions of AlMe2F units into the Zr⋅⋅⋅(μ‐F) bond.
Hydrogen‐Transfer‐Mediated α‐Functionalization of 1,8‐Naphthyridines by a Strategy Overcoming the Over‐Hydrogenation Barrier
Authors: Chen Xiu‐Wen , Zhao He , Chen Chun‐Lian , Jiang Huan‐Feng , Zhang Min
Published: September 2017

A general catalytic hydrogen transfer‐mediated α‐functionalization of 1,8‐naphthyridines is reported for the first time that benefits from a hydrogen transfer‐mediated activation mode for non‐activated pyridyl cores. The pyridyl α‐site selectively couples with the C8‐site of various tetrahydroquinolines (THQs) to afford novel α‐functionalized tetrahydro 1,8‐naphthyridines, a class of synthetically useful building blocks and potential candidates for the discovery of therapeutic and bio‐active products. The utilization of THQs as inactive hydrogen donors (HDs) appears to be a key strategy to overcome the over‐hydrogenation barrier and address the chemoselectivity issue. The developed chemistry features operational simplicity, readily available catalyst and good functional group tolerance, and offers a significant basis for further development of new protocols to directly transform or functionalize inert N‐heterocycles.
Stereospezifische Reaktion von Donor‐Akzeptor‐Cyclopropanen mit Thioketonen: ein Zugang zu hoch substituierten Tetrahydrothiophenen
Authors: Augustin André U. , Sensse Maximilian , Jones Peter G. , Werz Daniel B.
Published: September 2017

Lewis‐Säure‐katalysierte Reaktionen von 2‐substituierten Cyclopropandicarboxylaten mit Thioketonen werden beschrieben. In einem stereospezifischen Prozess wurden unter milden Bedingungen und der Verwendung von AlCl3 als Lewis‐Säure hoch substituierte Tetrahydrothiophene mit zwei benachbarten quartären Kohlenstoffatomen in hohen Ausbeuten erhalten. Ferner konnte eine intramolekulare Version verwirklicht werden, die den Zugang zu Schwefel‐überbrückten [n.2.1]bicyclischen Ringsystemen ermöglicht. Die Umsetzung von Selenoketonen, den höheren Analoga der Thioketone, unter ähnlichen Bedingungen führt zur Bildung verschiedener Tetrahydroselenophene.
Synthesis of a Metallo‐Iminosilane via a Silanone–Metal π‐Complex
Authors: Hadlington Terrance J. , Szilvási Tibor , Driess Matthias
Published: September 2017

Facile oxygenation of the acyclic amido‐chlorosilylene bis(N‐heterocyclic carbene) Ni0 complex [{N(Dipp)(SiMe3)ClSi:→Ni(NHC)2] (1; Dipp=2,6‐iPr2C6H4; N‐heterocyclic carbene=C[(iPr)NC(Me)]2) with N2O furnishes the first Si‐metalated iminosilane, [DippN=Si(OSiMe3)Ni(Cl)(NHC)2] (3), in a rearrangement cascade. Markedly, the formation of 3 proceeds via the silanone (Si=O)–Ni π‐complex 2 as the initial product, which was predicted by DFT calculations and observed spectroscopically. The Si=O and Si=N moieties in 2 and 3, respectively, show remarkable hydroboration reactivity towards H−B bonds of boranes, in the former case corroborating the proposed formation of a (Si=O)–Ni π‐complex at low temperature.
Polyamine‐Mediated Stoichiometric Assembly of Ribonucleoproteins for Enhanced mRNA Delivery
Authors: Li Jiahe , He Yanpu , Wang Wade , Wu Connie , Hong Celestine , Hammond Paula T.
Published: September 2017

Messenger RNA (mRNA) represents a promising class of nucleic acid drugs. Although numerous carriers have been developed for mRNA delivery, the inefficient mRNA expression inside cells remains a major challenge. Inspired by the dependence of mRNA on 3′‐terminal polyadenosine nucleotides (poly A) and poly A binding proteins (PABPs) for optimal expression, we complexed synthetic mRNA containing a poly A tail with PABPs in a stoichiometric manner and stabilized the ribonucleoproteins (RNPs) with a family of polypeptides bearing different arrangements of cationic side groups. We found that the molecular structure of these polypeptides modulates the degree of PABP‐mediated enhancement of mRNA expression. This strategy elicits an up to 20‐fold increase in mRNA expression in vitro and an approximately fourfold increase in mice. These findings suggest a set of new design principles for gene delivery by the synergistic co‐assembly of mRNA with helper proteins.
Organocatalytic Enantioselective Protonation for Photoreduction of Activated Ketones and Ketimines Induced by Visible Light
Authors: Lin Lu , Bai Xiangbin , Ye Xinyi , Zhao Xiaowei , Tan Choon‐Hong , Jiang Zhiyong
Published: September 2017

The first catalytic asymmetric photoreduction of 1,2‐diketones and α‐keto ketimines under visible light irradiation is reported. A transition‐metal‐free synergistic catalysis platform harnessing dicyanopyrazine‐derived chromophore (DPZ) as the photoredox catalyst and a non‐covalent chiral organocatalyst is effective for these transformations. With the flexible use of a chiral Brønsted acid or base in H+ transfer interchange to control the elusive enantioselective protonation, a variety of chiral α‐hydroxy ketones and α‐amino ketones were obtained with high yields and enantioselectivities.
A Simple and Broadly Applicable C−N Bond Forming Dearomatization Protocol Enabled by Bifunctional Amino Reagents
Authors: Ma Xiaofeng , Farndon Joshua J. , Young Tom A. , Fey Natalie , Bower John F.
Published: September 2017

A C−N bond forming dearomatization protocol with broad scope is outlined. Specifically, bifunctional amino reagents are used for sequential nucleophilic and electrophilic C−N bond formations, with the latter effecting the key dearomatization step. Using this approach, γ‐arylated alcohols are converted to a wide range of differentially protected spirocyclic pyrrolidines in just two or three steps.
Differences in protein expression among five species of stream stonefly (Plecoptera) along a latitudinal gradient in Japan
Authors: Gamboa Maribet , Tsuchiya Maria Claret , Matsumoto Suguru , Iwata Hisato , Watanabe Kozo
Published: September 2017

Proteome variation among natural populations along an environmental gradient may provide insights into how the biological functions of species are related to their local adaptation. We investigated protein expression in five stream stonefly species from four geographic regions along a latitudinal gradient in Japan with varying climatic conditions. The extracted proteins were separated by two‐dimensional gel electrophoresis and identified by matrix‐assisted laser desorption/ionization of time‐of‐flight (MALDI TOF/TOF), yielding 446 proteins. Low interspecies variation in the proteome profiles was observed among five species within geographical regions, presumably due to the co‐occurring species sharing the environments. However, large spatial variations in protein expression were found among four geographic regions, suggesting strong regulation of protein expression in heterogeneous environments, where the spatial variations were positively correlated with water temperature. We identified 21 unique proteins expressed specifically in a geographical region and six common proteins expressed throughout all regions. In warmer regions, metabolic proteins were upregulated, whereas proteins related to cold stress, the photoperiod, and mating were downregulated. Oxygen‐related and energy‐production proteins were upregulated in colder regions with higher altitudes. Thus, our proteomic approach is useful for identifying and understanding important biological functions related to local adaptations by populations of stoneflies.
What makes an effective clinical query and querier?
Authors: Koopman Bevan , Zuccon Guido , Bruza Peter
Published: September 2017

In this paper, we perform an in‐depth study into how clinicians represent their information needs and the influence this has on information retrieval (IR) effectiveness. While much research in IR has considered the effectiveness of IR systems, there is still a significant gap in the understanding of how users contribute to the effectiveness of these systems. The paper aims to contribute to this by studying how clinicians search for information. Multiple representations of an information need—from verbose patient case descriptions to ad‐hoc queries—were considered in order to understand their effect on retrieval. Four clinicians provided queries and performed relevance assessment to form a test collection used in this study. The different query formulation strategies of each clinician, and their effectiveness, were investigated. The results show that query formulation had more impact on retrieval effectiveness than the particular retrieval systems used. The most effective queries were short, ad‐hoc keyword queries. Different clinicians were observed to consistently adopt specific query formulation strategies. The most effective queriers were those who, given their information need, inferred novel keywords most likely to appear in relevant documents. This study reveals aspects of how people search within the clinical domain. This can help inform the development of new models and methods that specifically focus on the query formulation process to improve retrieval effectiveness.
Thermal melt circular dichroism spectroscopic studies for identifying stabilising amphipathic molecules for the voltage‐gated sodium channel NavMs
Authors: Ireland Sam M. , Sula Altin , Wallace B.A.
Published: September 2017

Purified integral membrane proteins require amphipathic molecules to maintain their solubility in aqueous solutions. These complexes, in turn, are used in studies to characterise the protein structures by a variety of biophysical and structural techniques, including spectroscopy, crystallography, and cryo‐electron microscopy. Typically the amphilphiles used have been detergent molecules, but more recently they have included amphipols, which are polymers of different sizes and compositions designed to create smaller, more well‐defined solubilised forms of the membrane proteins. In this study we used circular dichroism spectroscopy to compare the secondary structures and thermal stabilities of the NavMs voltage‐gated sodium channel in different amphipols and detergents as a means of identifying amphipathic environments that maximally maintain the protein structure whilst providing a stabilising environment. These types of characterisations also have potential as means of screening for sample types that may be more suitable for crystallisation and/or cryo‐electron microscopy structure determinations.
Characterizing community courts
Authors: Gal Tali , Dancig‐Rosenberg Hadar
Published: September 2017

Community courts (CCs) provide a therapeutic diversion for repeat low‐level offenders. This article explores the characteristics of two Israeli CCs using the Criminal Law Taxonomy (CLT), an instrument developed by the authors for assessing process‐, stakeholder‐, substance‐, and outcomes‐related characteristics of criminal justice mechanisms. Through court‐hearing observations and a process of multi‐rater coding of cases, the article analyzes the courtroom dynamics according to a set of 13 measurable parameters. The process was conceived as a vehicle for promoting the model goals: it was highly offender‐oriented and involved a needs‐based terminology while allowing for restrained expression of emotion. However, the process included no victim–offender dialogue and offender supporters and community representatives were only partially involved. The findings provide information about the program's implementation integrity; they also offer a basis for comparison with the characteristics of other justice mechanisms. While focusing on an Israeli program, the issues the article addresses reflect practices and controversies that are salient in many jurisdictions worldwide.
Biosynthetic Machinery of Diterpene Pleuromutilin Isolated from Basidiomycete Fungi
Authors: Yamane Momoka , Minami Atsushi , Liu Chengwei , Ozaki Taro , Takeuchi Ichiro , Tsukagoshi Tae , Tokiwano Tetsuo , Gomi Katsuya , Oikawa Hideaki
Published: September 2017

The diterpene pleuromutilin is a ribosome‐targeting antibiotic isolated from basidiomycete fungi, such as Clitopilus pseudo‐pinsitus. The functional characterization of all biosynthetic enzymes involved in pleuromutilin biosynthesis is reported and a biosynthetic pathway proposed. In vitro enzymatic reactions and mutational analysis revealed that a labdane‐related diterpene synthase, Ple3, catalyzed two rounds of cyclization from geranylgeranyl diphosphate to premutilin possessing a characteristic 5–6–8‐tricyclic carbon skeleton. Biotransformation experiments utilizing Aspergillus oryzae transformants possessing modification enzyme genes allowed the biosynthetic pathway from premutilin to pleuromutilin to be proposed. The present study sets the stage for the enzymatic synthesis of natural products isolated from basidiomycete fungi, which are a prolific source of structurally diverse and biologically active terpenoids.
Multistage Li1.2Ni0.2Mn0.6O2 Micro‐architecture towards High‐Performance Cathode Materials for Lithium‐Ion Batteries
Authors: He Wei , Zheng Hongfei , Ju Xiaokang , Li Shengyang , Ma Yating , Xie Qingshui , Wang Laisen , Qu Baihua , Peng Dong‐Liang
Published: September 2017

Constructing hierarchical‐architecture primary nanoparticles that assemble with secondary micro‐architectures is very effective to achieve high‐performance cathode materials for lithium‐ion batteries (LIBs). In this work, well‐crystallized lithium‐rich layered oxide cathode materials Li1.2Ni0.2Mn0.6O2 (LNMO) with a micro‐architecture was successfully synthesized. The preparation process is divided into two steps: the solvothermal process synthesizes the precursor Ni0.25Mn0.75CO3 (NMCO) and gradient temperature calcination is used to prepare the primary nanoparticles that agglomerate into hierarchical microspheres for final‐product LNMO. The as‐prepared material was used as cathode materials for LIBs, which exhibit good cycle life and excellent rate performances. The material retains a fairly high discharge capacity of approximately 180 mAh g−1 after 180 cycles at the 2C rate (1C=200 mA g−1). Even after a 50‐fold (5C/0.1C) increase, a discharge capacity 61.4 %  (153.8 mAh g−1) of the capacity at 0.1C (ca. 249.1 mAh g−1) could be retained. This superior cycle life and rate performance are attributed to the merits of the hierarchical nano‐/microsphere structures.
Structural‐Defect‐Controlled Electrochemical Performance of Sodium Ion Batteries with NaCrO2 Cathodes
Authors: Sawicki Monica , Ortiz Angel L. , Luo Mei , Shaw Leon L.
Published: September 2017

In this study, we report the effects of structural defects on the electrochemical cycle stability of Na‐ion batteries made of NaCrO2 cathodes. Three processing conditions are used to create NaCrO2 with different structural defects. One condition entails high‐energy ball milling of reactants before the solid‐state reaction at 900 °C, the second one has no high‐energy ball milling but simple mixing of reactants before the solid‐state reaction, and the last one has high‐energy ball milling after the solid‐state reaction. The NaCrO2 crystals derived from the process with high‐energy ball milling of reactants before the solid‐state reaction exhibit the best bulk conductivity and highest specific capacity with little capacity decay over 46 charge/discharge cycles. In contrast, the NaCrO2 crystals derived from the process without high‐energy ball milling have significant capacity decay, whereas the NaCrO2 crystals obtained from the process with high‐energy ball milling after the solid‐state reaction exhibits the lowest bulk conductivity and very low specific capacities. The different electrochemical properties exhibited by these NaCrO2 crystals have been ascribed to different extents of structural defects present in these crystals. This study unambiguously demonstrates that structural defects in NaCrO2 crystals are critical in achieving NaCrO2 electrodes with high specific capacity and excellent capacity retention.
Rational Design of a Bifunctional, Two‐Fold Interpenetrated ZnII‐Metal–Organic Framework for Selective Adsorption of CO2 and Efficient Aqueous Phase Sensing of 2,4,6‐Trinitrophenol
Authors: Singh Dhankhar Sandeep , Sharma Nayuesh , Kumar Sandeep , Dhilip Kumar T. J. , Nagaraja C. M.
Published: September 2017

A bifunctional, microporous ZnII metal–organic framework, [Zn2(NH2BDC)2(dpNDI)]n (MOF1) (where, NH2BDC=2‐aminoterephthalic acid, dpNDI=N,N′‐di(4‐pyridyl)‐1,4,5,8‐naphthalenediimide) has been synthesized solvothermally. MOF1 shows an interesting two‐fold interpenetrated, 3D pillar‐layered framework structure composed of two types of 1D channels with dimensions of approximately 2.99×3.58 Å and 4.58×5.38 Å decorated with pendent −NH2 groups. Owing to the presence of a basic functionalized pore surface, MOF1 exhibits selective adsorption of CO2 with high value of heat of adsorption (Qst=46.5 kJ mol−1) which is further supported by theoretically calculated binding energy of 48.4 kJ mol−1. Interestingly, the value of Qst observed for MOF1 is about 10 kJ mol−1 higher than that of analogues MOF with the benzene‐1,4‐dicarboxylic acid (BDC) ligand, which establishes the critical role of the −NH2 group for CO2 capture. Moreover, MOF1 exhibits highly selective and sensitive sensing of the nitroaromatic compound (NAC), 2,4,6‐trinitrophenol (TNP) over other competing NACs through a luminescence quenching mechanism. The observed selectivity for TNP over other nitrophenols has been correlated to stronger hydrogen bonding interaction of TNP with the basic −NH2 group of MOF1, which is revealed from DFT calculations. To the best of our knowledge, MOF1 is the first example of an interpenetrated ZnII‐MOF exhibiting selective adsorption of CO2 as well as efficient aqueous‐phase sensing of TNP; investigated through combined experimental and theoretical studies.
Quasi‐Emulsion Confined Synthesis of Edge‐Rich Ultrathin MoS2 Nanosheets/Graphene Hybrid for Enhanced Hydrogen Evolution
Authors: Yin Xuying , Yan Ya , Miao Mao , Zhan Ke , Li Pingwei , Yang Junhe , Zhao Bin , Xia Bao Yu
Published: September 2017

High‐purity hydrogen produced by water splitting is considered as one of the most promising fuels to replace traditional fossil fuels. Developing highly efficient electrocatalysts toward hydrogen evolution is vital for the realization of large‐scale H2 generation. Glycerol is used herein in a facile solvothermal process to synthesize edge‐rich ultrathin MoS2/reduced graphene oxide (RGO) composites. The introduction of glycerol plays an important role in the formation of such interesting structures. The MoS2/RGO electrocatalyst exhibits excellent hydrogen evolution reaction (HER) activity and remarkable stability, owing to the rich active edges and improved electrical conductivity of the catalyst composites. This work provides new insights to engineer the structures of MoSx‐based composites and thus achieves more active and efficient electrocatalysts.
One‐Pot Synthesis of Size‐Controllable Core–Shell CdS and Derived CdS@ZnxCd1−xS Structures for Photocatalytic Hydrogen Production
Authors: Kai Shuangshuang , Xi Baojuan , Wang Yifeng , Xiong Shenglin
Published: September 2017

Chalcogenide micro/nanocomposite structures have been attracting worldwide attention due to prospective applications in photocatalytic hydrogen production. Well‐defined micro/nanostructures with pronounced properties are of extraordinary importance. Herein, a facile one‐pot method for the synthesis of monodisperse, size‐controllable CdS core–shell and CdS@ZnxCd1−xS core–double shell submicrospheres, which were engineered with respect to structure and size, is reported. CdS core–shell submicrospheres with different sizes were selectively prepared for the first time. The growth mechanism was investigated in detail by monitoring the time‐dependent morphology of intermediates by TEM. By introduction of a zinc precursor in the synthetic system, CdS@ZnxCd1−xS core–double shell submicrospheres were obtained by cation exchange of CdS with zinc ions, with a process of diffusion of CdS towards the outside and transformation of ZnxCd1−xS crystallites. The H2 evolution rate over CdS@CdxZn1−xS (5.17 mmol h−1 g−1) is 12.3 times that of CdS core–shell structures (0.42 mmol h−1 g−1) under visible light, owing to the efficient charge separation, as demonstrated by electrochemical impedance and transient‐state time‐resolved photoluminescence spectroscopy. Furthermore, CdS@ZnxCd1−xS core–double shell structures exhibited excellent stability over 20 h of hydrogen production.
Co3O4 Nanowire Arrays toward Superior Water Oxidation Electrocatalysis in Alkaline Media by Surface Amorphization
Authors: Zhou Dan , He Liangbo , Zhang Rong , Hao Shuai , Hou Xiandeng , Liu Zhiang , Du Gu , Asiri Abdullah M. , Zheng Chengbin , Sun Xuping
Published: September 2017

It is highly desirable to develop a simple, fast and straightforward method to boost the alkaline water oxidation of metal oxide catalysts. In this communication, we report our recent finding that the generation of amorphous Co‐borate layer on Co3O4 nanowire arrays supported on Ti mesh (Co3O4@Co‐Bi NA/TM) leads to significantly boosted OER activity. The as‐prepared Co3O4@Co‐Bi NA/TM demands overpotential of 304 mV to drive a geometrical current density of 20 mA cm‐2 in 1.0 M KOH, which is 109 mV less than that for Co3O4 NA/TM, with its catalytic activity being preserved for at least 20 h. It suggests that the existence of amorphous Co‐Bi layer promotes more CoOx(OH)y generation on Co3O4 surface.
Synergistic Configuration of Diols as Brønsted Bases
Authors: Kim Ye‐Jin , Rakshit Surajit , Jin Geun Young , Ghosh Prasun , Lee Young Min , Park Won‐Woo , Kim Yung Sam , Kwon Oh‐Hoon
Published: September 2017

As viscous hydroxylic organic compounds, diols are of interest for their functional molecular conformation, which is based on inter‐ and intramolecular hydrogen (H)‐bonds. By utilising steady‐state electronic and vibrational spectroscopy, time‐resolved fluorescence spectroscopy, and computational analyses, we report the association of the hydroxyl groups of diols via intra‐ or intermolecular H‐bonds to enhance their reactivity as a base. Whereas the formation of an intermolecularly H‐bonded dimer is requisite for diols of weak intramolecular H‐bond to extract a proton from a model strong photoacid, a well‐configured single diol molecule with an optimised intramolecular H‐bond is revealed to serve as an effective Brønsted base with increased basicity. This observation highlights the collective role of H‐bonding in acid–base reactions, and provides mechanistic backgrounds to understand the reactivity of polyols in the acid‐catalysed dehydration for the synthesis of cyclic ethers at the molecular level.
Synthesis of Thiophene‐Based Optical Ligands That Selectively Detect Tau Pathology in Alzheimer's Disease
Authors: Shirani Hamid , Appelqvist Hanna , Bäck Marcus , Klingstedt Therése , Cairns Nigel J. , Nilsson K. Peter R.
Published: September 2017

The accumulation of protein aggregates is associated with many devastating neurodegenerative diseases and the development of molecular ligands able to detect these pathological hallmarks is essential. Here, the synthesis of thiophene based optical ligands, denoted bi‐thiophene‐vinyl‐benzothiazoles (bTVBTs) that can be utilized for selective assignment of tau aggregates in brain tissue with Alzheimer's disease (AD) pathology is reported. The ability of the ligands to selectively distinguish tau deposits from the other AD associated pathological hallmark, senile plaques consisting of aggregated amyloid‐β (Aβ) peptide, was reduced when the chemical composition of the ligands was altered, verifying that specific molecular interactions between the ligands and the aggregates are necessary for the selective detection of tau deposits. Our findings provide the structural and functional basis for the development of new fluorescent ligands that can distinguish between aggregated proteinaceous species consisting of different proteins. In addition, the bTVBT scaffold might be utilized to create powerful practical research tools for studying the underlying molecular events of tau aggregation and for creating novel agents for clinical imaging of tau pathology in AD.
Understanding the Catalytic Mechanism and the Nature of the Transition State of an Attractive Drug‐Target Enzyme (Shikimate Kinase) by Quantum Mechanical/Molecular Mechanical (QM/MM) Studies
Authors: Yao Jianzhuang , Wang Xia , Luo Haixia , Gu Pengfei
Published: September 2017

Shikimate kinase (SK) is the fifth bacterial enzyme involved in the shikimate pathway for biosynthesis of life‐indispensable components, such as aromatic amino acids. The absence of the shikimate pathway in humans makes SK an attractive target for the rational design of drugs aimed at pathogenesis bacteria, such as Mycobacterium tuberculosis and Helicobacter pylori. However, an effective inhibitor of SK (e.g., a transition‐state analogue) is still not available on the market due, at least in part, to a lack of knowledge on the catalytic mechanism and the nature of the rate‐limiting transition state. Herein, quantum mechanical/molecular mechanical (QM/MM) reaction coordinate, molecular dynamics (MD), and free‐energy simulations have been performed to answer these questions. The results presented herein demonstrate that the phosphoryl‐transfer process, which is the rate‐limiting step of SK‐catalyzed phosphorylation of shikimic acid (SKM), is a concerted one‐step reaction proceeding through a loose transition state. The computational results agree well with those of experimental studies, specifically NMR results, X‐ray crystal structure observation, and activation free‐energy barrier.
Better Organic Ternary Memory Performance through Self‐Assembled Alkyltrichlorosilane Monolayers on Indium Tin Oxide (ITO) Surfaces
Authors: Hou Xiang , Cheng Xue‐Feng , Zhou Jin , He Jing‐Hui , Xu Qing‐Feng , Li Hua , Li Na‐Jun , Chen Dong‐Yun , Lu Jian‐Mei
Published: September 2017

Recently, surface engineering of the indium tin oxide (ITO) electrode of sandwich‐like organic electric memory devices was found to effectively improve their memory performances. However, there are few methods to modify the ITO substrates. In this paper, we have successfully prepared alkyltrichlorosilane self‐assembled monolayers (SAMs) on ITO substrates, and resistive random access memory devices are fabricated on these surfaces. Compared to the unmodified ITO substrates, organic molecules (i.e., 2‐((4‐butylphenyl)amino)‐4‐((4‐butylphenyl)iminio)‐3‐oxocyclobut‐1‐en‐1‐olate, SA‐Bu) grown on these SAM‐modified ITO substrates have rougher surface morphologies but a smaller mosaicity. The organic layer on the SAM‐modified ITO further aged to eliminate the crystalline phase diversity. In consequence, the ternary memory yields are effectively improved to approximately 40–47 %. Our results suggest that the insertion of alkyltrichlorosilane self‐assembled monolayers could be an efficient method to improve the performance of organic memory devices.
Randomized controlled trial of increasing physical activity on objectively measured and self‐reported cognitive functioning among breast cancer survivors: The memory & motion study
Authors: Hartman Sheri J. , Nelson Sandahl H. , Myers Emily , Natarajan Loki , Sears Dorothy D. , Palmer Barton W. , Weiner Lauren S. , Parker Barbara A. , Patterson Ruth E.
Published: September 2017

BACKGROUND

Increasing physical activity can improve cognition in healthy and cognitively impaired adults; however, the benefits for cancer survivors are unknown. The current study examined a 12‐week physical activity intervention, compared with a control condition, on objective and self‐reported cognition among breast cancer survivors.

METHODS

Sedentary breast cancer survivors were randomized to an exercise arm (n = 43) or a control arm (n = 44). At baseline and at 12 weeks, objective cognition was measured with the National Institutes of Health Cognitive Toolbox, and self‐reported cognition using the Patient‐Reported Outcomes Measurement Information System scales. Linear mixed‐effects regression models tested intervention effects for changes in cognition scores.

RESULTS

On average, participants (n = 87) were aged 57 years (standard deviation, 10.4 years) and were 2.5 years (standard deviation, 1.3 years) post surgery. Scores on the Oral Symbol Digit subscale (a measure of processing speed) evidenced differential improvement in the exercise arm versus the control arm (b = 2.01; P < .05). The between‐group differences in improvement on self‐reported cognition were not statistically significant but were suggestive of potential group differences. Time since surgery moderated the correlation, and participants who were ≤2 years post surgery had a significantly greater improvement in Oral Symbol Digit score (exercise vs control (b = 4.00; P < .01), but no significant improvement was observed in patients who were >2 years postsurgery (b = −1.19; P = .40). A significant dose response was observed with greater increased physical activity associated with objective and self‐reported cognition in the exercise arm.

CONCLUSIONS

The exercise intervention significantly improved processing speed, but only among those who had been diagnosed with breast cancer within the past 2 years. Slowed processing speed can have substantial implications for independent functioning, supporting the potential importance of early implementation of an exercise intervention among patients with breast cancer. Cancer 2018;124:192‐202. © 2017 American Cancer Society.