bluuebunny/crossref_metadata_2025 huggingface dataset:
Ag@Sn Core‐Shell Powder Preform with a High Re‐Melting Temperature for High‐Temperature Power Devices Packaging
Authors: Yu Fuwen , Wang Bin , Guo Qiang , Ma Xin , Li Mingyu , Chen Hongtao
Published: August 2017

In this paper, the authors propose a highly conductive die attach material based on Ag@Sn powder for power devices operating at high temperatures or in other harsh environments. The preform can be reflowed at 250 °C (18 °C above the Tm of Sn, 232 °C), but the resulting bondline can sustain high temperatures up to 400 °C with a high shear strength due to the high re‐melting temperature of the formed Ag3Sn (Tm = 480 °C) after the complete consumption of the outer Sn layers. In addition, the formed bondline exhibits excellent electrical and thermal conductivities due to the embedded Ag particles in the interconnections. The interconnections also exhibit excellent reliability under thermal shock cycling from −55 to 200 °C because of the increased bondline thickness and inherent ductility of the Ag particles embedded in the Ag3Sn.
Self‐Assembled Hydrogel Fiber Bundles from Oppositely Charged Polyelectrolytes Mimic Micro‐/Nanoscale Hierarchy of Collagen
Authors: Sant Shilpa , Coutinho Daniela F. , Gaharwar Akhilesh K. , Neves Nuno M. , Reis Rui L. , Gomes Manuela E. , Khademhosseini Ali
Published: August 2017

Fiber bundles are present in many tissues throughout the body. In most cases, collagen subunits spontaneously self‐assemble into a fibrilar structure that provides ductility to bone and constitutes the basis of muscle contraction. Translating these natural architectural features into a biomimetic scaffold still remains a great challenge. Here, a simple strategy is proposed to engineer biomimetic fiber bundles that replicate the self‐assembly and hierarchy of natural collagen fibers. The electrostatic interaction of methacrylated gellan gum with a countercharged chitosan polymer leads to the complexation of the polyelectrolytes. When directed through a polydimethylsiloxane channel, the polyelectrolytes form a hierarchical fibrous hydrogel demonstrating nanoscale periodic light/dark bands similar to D‐periodic bands in native collagen and align parallel fibrils at microscale. Importantly, collagen‐mimicking hydrogel fibers exhibit robust mechanical properties (MPa scale) at a single fiber bundle level and enable encapsulation of cells inside the fibers under cell‐friendly mild conditions. Presence of carboxyl‐ (in gellan gum) or amino‐ (in chitosan) functionalities further enables controlled peptide functionalization such as Arginylglycylaspartic acid (RGD) for biochemical mimicry (cell adhesion sites) of native collagen. This biomimetic‐aligned fibrous hydrogel system can potentially be used as a scaffold for tissue engineering as well as a drug/gene delivery vehicle.
Plasmonic Dual‐Enhancement and Precise Color Tuning of Gold Nanorod@SiO2 Coupled Core–Shell–Shell Upconversion Nanocrystals
Authors: Kang Fengwen , He Jijun , Sun Tianying , Bao Zhi Yong , Wang Feng , Lei Dang Yuan
Published: August 2017

The last decade has witnessed the remarkable research progress of lanthanide‐doped upconversion nanocrystals (UCNCs) at the forefront of promising applications. However, the future development and application of UCNCs are constrained greatly by their underlying shortcomings such as significant nonradiative processes, low quantum efficiency, and single emission colors. Here a hybrid plasmonic upconversion nanostructure consisting of a GNR@SiO2 coupled with NaGdF4:Yb3+,Nd3+@NaGdF4:Yb3+,Er3+@NaGdF4 core–shell–shell UCNCs is rationally designed and fabricated, which exhibits strongly enhanced UC fluorescence (up to 20 folds) and flexibly tunable UC colors. The experimental findings show that controlling the SiO2 spacer thickness enables readily manipulating the intensity ratio of the Er3+ red, green, and blue emissions, thereby allowing us to achieve the emission color tuning from pale yellow to green upon excitation at 808 nm. Electrodynamic simulations reveal that the tunable UC colors are due to the interplay of plasmon‐mediated simultaneous excitation and emission enhancements in the Er3+ green emission yet only excitation enhancement in the blue and red emissions. The results not only provide an upfront experimental design for constructing hybrid plasmonic UC nanostructures with high efficiency and color tunability, but also deepen the understanding of the interaction mechanism between the Er3+ emissions and plasmon resonances in such complex hybrid nanostructure.
Lipase‐Initiated Tandem Biginelli Reactions via in situ‐Formed Acetaldehydes in One Pot: Discovery of Single‐Ring Deep Blue Luminogens
Authors: Zhang Wei , Wang Na , Yang Zeng‐Jie , Li Yan‐Rong , Yu Yuan , Pu Xue‐Mei , Yu Xiao‐Qi
Published: August 2017

A facile approach for the synthesis of 3,4‐dihydropyrimidin‐2(1H)‐ones was developed by a tandem multi‐component reaction (MCR) in one pot. This approach involves two steps, lipase‐catalyzed in situ generation of acetaldehyde and the Biginelli reaction in turn. Several control experiments were performed using acetaldehydes directly to explore the possible mechanism of this procedure. Moreover, owing to the distinct modularity and highly efficient features of the MCR, it can assemble libraries of structurally diverse products (yields up to 98% under the optimized conditions in this paper) and provides an exceptional synthesis tool for the discovery of the minimal deep‐blue luminogen in the solid state, namely, a single ring.

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Nitrile as a Versatile Directing Group for C(sp2)–H Functionalizations
Authors: Ping Yuanyuan , Wang Liping , Ding Qiuping , Peng Yiyuan
Published: August 2017

The one‐step direct regioselective functionaliztion of inert C(sp2)–H bonds is an efficient and sustainable methodology for the synthesis of a variety of useful natural products and pharmaceutical intermediates. A range of functional groups have been widely used as directing group for various regioselective transformations. Among these, the weakly coordinating nitrile group has attracted much attention because it is a transformable, easily installed and readily removed directing group, which can be easily converted into a number of different functional groups, such as carboxyl, carbamoyl, aminomethyl, carbonyl, and heterocyclic functionalities. This review describes recent advances in nitrile‐directed C–H functionalizations catalyzed by palladium(II), ruthenium(II), rhodium(III) and iridium(I) catalysts. The review is divided into sections related to ortho‐, meta‐, and para‐C–H bond functionalizations, which are subdivided according to reaction type (olefination, arylation, halogenation, hydroxylation and acetoxylation).

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Weft‐Knitted Fabric for a Highly Stretchable and Low‐Voltage Wearable Heater
Authors: Zhang Mingchao , Wang Chunya , Liang Xiaoping , Yin Zhe , Xia Kailun , Wang Huimin , Jian Muqiang , Zhang Yingying
Published: August 2017

Wearable heaters have attracted broad attention due to their applications in personal heating systems and healthcare management, such as heat preservation in textile/clothing and thermotherapy. Protecting heating performance against deterioration under large deformation is is important for the application of wearable heaters. Here, a highly stretchable electrically driven heater based on electrically conductive weft‐knitted fabrics is reported, which can be transformed from traditional fabrics through a facile heat treatment process. As an example, a heater made from Modal shows a heating temperature higher than 100 °C at a driving voltage as low as 3 V. The Joule heating performance of the heater does not deteriorate even under a large strain of 70%. Furthermore, according to theoretical analysis and experimental results, the output power and saturated temperature of the heater under a certain voltage can be easily tuned by tailoring the shape and size of the fabric to meet customized demands. The superior performance of the heater originates from the weft‐knitted structural configuration. Finally, the application of the ultrastretchable heater in wearable thermal therapy devices is demonstrated, showing its great potential in wearable electronics.
Nanoscale Morphology of Doctor Bladed versus Spin‐Coated Organic Photovoltaic Films
Authors: Pokuri Balaji Sesha Sarath , Sit Joseph , Wodo Olga , Baran Derya , Ameri Tayebeh , Brabec Christoph J. , Moule Adam J. , Ganapathysubramanian Baskar
Published: August 2017

Recent advances in efficiency of organic photovoltaics are driven by judicious selection of processing conditions that result in a “desired” morphology. An important theme of morphology research is quantifying the effect of processing conditions on morphology and relating it to device efficiency. State‐of‐the‐art morphology quantification methods provide film‐averaged or 2D‐projected features that only indirectly correlate with performance, making causal reasoning nontrivial. Accessing the 3D distribution of material, however, provides a means of directly mapping processing to performance. In this paper, two recently developed techniques are integrated—reconstruction of 3D morphology and subsequent conversion into intuitive morphology descriptors —to comprehensively image and quantify morphology. These techniques are applied on films generated by doctor blading and spin coating, additionally investigating the effect of thermal annealing. It is found that morphology of all samples exhibits very high connectivity to electrodes. Not surprisingly, thermal annealing consistently increases the average domain size in the samples, aiding exciton generation. Furthermore, annealing also improves the balance of interfaces, enhancing exciton dissociation. A comparison of morphology descriptors impacting each stage of photophysics (exciton generation, dissociation, and charge transport) reveals that spin‐annealed sample exhibits superior morphology‐based performance indicators. This suggests substantial room for improvement of blade‐based methods (process optimization) for morphology tuning to enhance performance of large area devices.
Social Determinants of Health: A Missing Link in Emergency Medicine Training
Authors: Axelson Daniel J. , Stull Matthew J. , Coates Wendy C.
Published: August 2017

The health of a population depends upon several factors, including disease, public health initiatives, and the social determinants of health (SDH). These factors often converge in the emergency department (ED) where the impact of social conditions such as homelessness, low‐literacy, and poverty lead to recidivism and may contribute to provider burnout. Inclusion of SDH topics in EM residency curricula can provide needed background information and effective strategies for coping with these patients in the clinical setting. Exercises that simulate poverty, the development of and familiarity with meaningful community partnerships, and inclusion of SDH topics in standard ED conferences (e.g., mortality and morbidity conference) can promote understanding and outline a detailed plan for treating patients facing these challenges. By incorporating educational interventions aimed at identifying and intervening on issues of SDH in the ED we may be able to better serve those patients who need us the most.
Ultrasound–assisted synthesis and characterization of polymethyl methacrylate/reduced graphene oxide nanocomposites
Authors: Poddar Maneesh Kumar , Pradhan Sushobhan , Moholkar Vijayanand S. , Arjmand Mohammad , Sundararaj Uttandaraman
Published: August 2017

This article reports ultrasound–assisted synthesis of polymethyl methacrylate (PMMA)/reduced graphene oxide (RGO) nanocomposites by in situ emulsion polymerization coupled with in situ reduction of graphene oxide. The thermal degradation kinetics of the nanocomposites was also assessed with Criado and Coats‐Redfern methods. Intense microconvection generated by ultrasound and cavitation results in uniform dispersion of RGO in the polymer matrix, which imparts markedly higher physical properties to resulting nanocomposites at low (≤1.0 wt %) RGO loadings, as compared to nanocomposites synthesized with mechanical stirring. Some important properties of the PMMA/RGO nanocomposites synthesized with sonication (with various RGO loadings) are: glass transition temperature (0.4 wt %) = 124.5°C, tensile strength (0.4 wt %) = 40.4 MPa, electrical conductivity (1.0 wt %) = 2 × 10−7 S/cm, electromagnetic interference shielding effectiveness (1.0 wt %) = 3.3 dB. Predominant thermal degradation mechanism of nanocomposites (1.0 wt % RGO) is 1D diffusion with activation energy of 111.3 kJ/mol. © 2017 American Institute of Chemical Engineers AIChE J, 64: 673–687, 2018
Selling Innovations Like Soap: The Interactive Systems Framework and Social Marketing
Authors: McAlindon Kathryn
Published: August 2017

Highlights

Many dissemination/implementation frameworks, including the ISF, focus primarily on implementation.

Social marketing, like dissemination, aims to communicate knowledge and behavior change.

Social marketing supplements frameworks like the ISF by communicating and promoting change.

Social marketing can improve the understanding of strategic communication in dissemination.
First‐line treatment selection and early monitoring patterns in chronic phase‐chronic myeloid leukemia in routine clinical practice: SIMPLICITY
Authors: Goldberg Stuart L. , Cortes Jorge E. , Gambacorti‐Passerini Carlo , Hehlmann Rüdiger , Khoury H. Jean , Michallet Mauricette , Paquette Ron L. , Simonsson Bengt , Zyczynski Teresa , Foreman Aimee , Abruzzese Elisabetta , Andorsky David , Beeker Aart , Cony‐Makhoul Pascale , Hansen Richard , Lomaia Elza , Olavarria Eduardo , Mauro Michael J.
Published: August 2017

Achieving successful outcomes in chronic phase‐chronic myeloid leukemia (CP‐CML) requires careful monitoring of cytogenetic/molecular responses (CyR/MR). SIMPLICITY (NCT01244750) is an observational study exploring tyrosine kinase inhibitor use and management patterns in patients with CP‐CML receiving first‐line imatinib (n = 416), dasatinib (n = 418) or nilotinib (n = 408) in the US and 6 European countries in routine clinical practice. Twelve‐month follow‐up data of 1242 prospective patients (enrolled October 01 2010‐September 02 2015) are reported. 81% of patients had baseline comorbidities. Treatment selection was based on perceived efficacy over patient comorbidity profile. There was a predominance of imatinib‐treated patients enrolled earlier in the study, with subsequent shift toward dasatinib‐ and nilotinib‐treated patients by 2013/2014. Monitoring for either CyR/MR improved over time and was documented for 36%, 82%, and 95% of patients by 3, 6, and 12 months, respectively; 5% had no documentation of CyR/MR monitoring during the first year of therapy. Documentation of MR/CyR testing was higher in Europe than the US (P < .001) and at academic versus community practices (P = .001). Age <65 years, patients being followed at sites within Europe, those followed at academic centers and patients no longer on first‐line therapy were more likely to be monitored by 12 months. SIMPLICITY demonstrates that the NCCN and ELN recommendations on response monitoring have not been consistently translated into routine clinical practice. In the absence of appropriate monitoring practices, clinical response to TKI therapy cannot be established, any needed changes to treatment strategy will thus not be implemented, and long‐term patient outcomes are likely to be impacted.
Diaphanospondylodysostosis and ischiospinal dysostosis, evidence for one disorder with variable expression in a patient who has survived to age 9 years
Authors: Legare Janet M. , Seaborg Kristin , Laffin Jennifer , Giampietro Philip F.
Published: August 2017

Diaphanospondylodysostosis (DSD) and ischiospinal dysostosis (ISD) are both rare skeletal dysplasias consisting of abnormal axial skeletal development but normal appendicular skeletal development. Both disorders recently have been found to result from mutations in the BMPER gene. We report a patient with one deletion and one mutation of the BMPER gene who has features most consistent with DSD but who has survived to age 9 years. Survival suggests that DSD and ISD reflect a spectrum of severity of one disease process.
Estimation of live birth and population prevalence of Down syndrome in nine U.S. states
Authors: de Graaf Gert , Buckley Frank , Dever Jennifer , Skotko Brian G.
Published: August 2017

For all of the U.S. states with sufficient data, we estimated live birth and population prevalences for Down syndrome (DS). As social service resources vary between states, such data are important for public policy discussions and state planning. We predicted the actual and nonselective live birth prevalence, and population prevalence, for DS in nine U.S. states based on publicly available datasets from the Centers for Disease Control and Prevention and the Integrated Public Use Microdata Series. As of 2010, we estimated a population size for people with DS of 4,554 in MA (population prevalence 1 in 1,440), 6,101 in NJ (1 in 1,443), 14,315 in NY (1 in 1,355), 9,739 in IL (1 in 1,319), 4,354 in IN (1 in 1,491), 7,295 in MI (1 in 1,354), 9,099 in FL (1 in 2,071), 3,014 in KY (1 in 1,442), and 3,596 in AZ (1 in 1,784). The number of people living with DS has steadily increased from 1950 until 2010 in these nine U.S. states. Population prevalence would have been higher absent DS‐related elective terminations. Racial and ethnic groups, other than non‐Hispanic whites, comprise a growing proportion within these DS communities, particularly among younger‐aged persons.
A Formal Total Synthesis of (+)‐Frondosin A
Authors: Kwon Kuktae , Ham Jin Su , Kim Hyoun Young , Sampath Vasu , Lee Hee‐Yoon
Published: August 2017

An enantio‐ and stereoselective formal total synthesis of (+)‐frondosin A was accomplished through an oxidopyrylium‐ion‐mediated [5+2] cycloaddition reaction. The cycloaddition reaction provided not only an efficient way of constructing the frondosin skeleton but also facial discrimination through an ether bridge for complete control of relative stereochemistry of the substituents in frondosin A.
Deuterium‐ und tritiummarkierte Verbindungen: Anwendungen in den modernen Biowissenschaften
Authors: Atzrodt Jens , Derdau Volker , Kerr William J. , Reid Marc
Published: August 2017

Wasserstoffisotope sind einzigartige Werkzeuge zur Identifizierung und Erforschung biologischer oder chemischer Vorgänge. Wasserstoffisotopenmarkierungen erlauben den spurlosen und direkten Einbau einer zusätzlichen Masseneinheit oder eines radioaktiven Markers in ein organisches Molekül, und dies praktisch ohne Änderungen der chemischen Struktur, der physikalischen Eigenschaften oder der biologischen Aktivität. Die Verwendung von deuteriummarkierten Isotopologen zur Untersuchung der spezifischen massenspektrometrischen (MS) Muster, die von Gemischen biologisch relevanter Moleküle hervorgerufen werden, ermöglicht eine drastische Vereinfachung der Analyse. Solche Methoden ermöglichen nun tiefe Einblicke in einen großen, kontinuierlich anwachsenden Bereich von Anwendungen in den Biowissenschaften und darüber hinaus. Speziell Tritium (3H) wird zunehmend eingesetzt, insbesondere in der pharmazeutischen Wirkstoffsuche. Aufwand und Kosten der Synthese markierter Verbindungen werden durch die hohe Empfindlichkeit der Analyse und hohe Zuverlässigkeit der erhaltenen Daten mehr als ausgeglichen. In diesem Aufsatz werden Fortschritte bei der Verwendung von Wasserstoffisotopen in den Biowissenschaften beschrieben.
A Stereoselective [3+1] Ring Expansion for the Synthesis of Highly Substituted Methylene Azetidines
Authors: Schmid Steven C. , Guzei Ilia A. , Schomaker Jennifer M.
Published: August 2017

The reaction of rhodium‐bound carbenes with strained bicyclic methylene aziridines results in a formal [3+1] ring expansion to yield highly substituted methylene azetidines with excellent regio‐ and stereoselectivity. The reaction appears to proceed through an ylide‐type mechanism, where the unique strain and structure of the methylene aziridine promotes a ring‐opening/ring‐closing cascade that efficiently transfers chirality from substrate to product. The resultant products can be elaborated into new azetidine scaffolds containing vicinal tertiary‐quaternary and even quaternary‐quaternary stereocenters.
Response to Comment on “A Liposomal System Capable of Generating CO2 Bubbles to Induce Transient Cavitation, Lysosomal Rupturing and Cell Necrosis”
Authors: Wan Wei‐Lin , Chung Min‐Fan , Shih Po‐Chien , Sung Hsing‐Wen
Published: August 2017

Leroux et al. haben Experimente aus unserer Studie wiederholt und berichten, dass sie das thermoresponsive liposomale System mit Ammoniumbicarbonat (ABC), für das wir Wirkstofffreisetzung unter mildem Erwärmen demonstrierten, nicht reproduzieren konnten. Wir widersprechen ihrer Beurteilung und spekulieren, dass die andersartige Methode, die Leroux et al. für die Herstellung des wässrigen ABC verwendeten, zu dem negativen Ergebnis führte.
Determinants of the Inhibition of DprE1 and CYP2C9 by Antitubercular Thiophenes
Authors: Liu Renhe , Lyu Xiaoxuan , Batt Sarah M , Hsu Mei‐Hui , Harbut Michael B , Vilchèze Catherine , Cheng Bo , Ajayi Kehinde , Yang Baiyuan , Yang Yun , Guo Hui , Lin Changyou , Gan Fei , Wang Chen , Franzblau Scott G. , Jacobs William R. , Besra Gurdyal S. , Johnson Eric F. , Petrassi Mike , Chatterjee Arnab K. , Fütterer Klaus , Wang Feng
Published: August 2017

Mycobacterium tuberculosis (Mtb) DprE1, an essential isomerase for the biosynthesis of the mycobacterial cell wall, is a validated target for tuberculosis (TB) drug development. Here we report the X‐ray crystal structures of DprE1 and the DprE1 resistant mutant (Y314C) in complexes with TCA1 derivatives to elucidate the molecular basis of their inhibitory activities and an unconventional resistance mechanism, which enabled us to optimize the potency of the analogs. The selected lead compound showed excellent in vitro and in vivo activities, and low risk of toxicity profile except for the inhibition of CYP2C9. A crystal structure of CYP2C9 in complex with a TCA1 analog revealed the similar interaction patterns to the DprE1–TCA1 complex. Guided by the structures, an optimized molecule was generated with differential inhibitory activities against DprE1 and CYP2C9, which provides insights for development of a clinical candidate to treat TB.
Osmium‐Mediated Transformation of 4‐Thiouridine to Cytidine as Key To Study RNA Dynamics by Sequencing
Authors: Riml Christian , Amort Thomas , Rieder Dietmar , Gasser Catherina , Lusser Alexandra , Micura Ronald
Published: August 2017

To understand the functional roles of RNA in the cell, it is essential to elucidate the dynamics of their production, processing and decay. A recent method for assessing mRNA dynamics is metabolic labeling with 4‐thiouridine (4sU), followed by thio‐selective attachment of affinity tags. Detection of labeled transcripts by affinity purification and hybridization to microarrays or by deep sequencing then reveals RNA expression levels. Here, we present a novel sequencing method (TUC‐seq) that eliminates affinity purification and allows for direct assessment of 4sU‐labeled RNA. It employs an OsO4‐mediated transformation to convert 4sU into cytosine. We exemplify the utility of the new method for verification of endogenous 4sU in tRNAs and for the detection of pulse‐labeled mRNA of seven selected genes in mammalian cells to determine the relative abundance of the new transcripts. The results prove TUC‐seq as a straight‐forward and highly versatile method for studies of cellular RNA dynamics.
Synthesis of Bicyclo[n.1.0]alkanes by a Cobalt‐Catalyzed Multiple C(sp3)−H Activation Strategy
Authors: Zhang Zhuo‐Zhuo , Han Ye‐Qiang , Zhan Bei‐Bei , Wang Sai , Shi Bing‐Feng
Published: August 2017

A cobalt‐catalyzed dual C(sp3)−H activation strategy has been developed and it provides a novel strategy for the synthesis of bicyclo[4.1.0]heptanes and bicyclo[3.1.0]hexanes. A key to the success of this reaction is the conformation‐induced methylene C(sp3)−H activation of the resulting cobaltabicyclo[4.n.1] intermediate. In addition, the synthesis of bicyclo[3.1.0]hexane from pivalamide, by a triple C(sp3)−H activation, has also been demonstrated.
Intracellular Delivery of Functional Native Antibodies under Hypoxic Conditions by Using a Biodegradable Silica Nanoquencher
Authors: Yuan Peiyan , Zhang Hailong , Qian Linghui , Mao Xin , Du Shubo , Yu Changmin , Peng Bo , Yao Shao Q.
Published: August 2017

Antibodies are important biopharmaceuticals, but almost all existing antibody‐based drugs are limited to targeting antigens located at the cell exterior because of the inability of antibodies to enter the cell interior. Available methods for intracellular delivery of antibodies have major shortcomings. Herein, we report an approach to encapsulate native antibodies in a biodegradable silica nanoquencher (BS‐qNP), which could undergo efficient cellular uptake and intracellular degradation to release antibodies only under hypoxic conditions. By coating the surface of BS‐qNP with cell‐penetrating poly(disulfide)s (CPD), the delivered antibodies (or other proteins) avoided endolysosomal trapping. Doping of the silica coating with a fluorescent dye and a dark hole quencher further endowed BS‐qNP with hypoxia‐responsive fluorescence turn‐on property. Our antibody delivery system thus provides the first platform capable of stable encapsulation, efficient uptake, on‐demand antibody release, and imaging of release/cell state.
Palladium‐Catalyzed Synthesis of Heteroarene‐Fused Cyclooctatetraenes through Dehydrogenative Cyclodimerization
Authors: Fukuzumi Keita , Nishii Yuji , Miura Masahiro
Published: August 2017

Arene‐fused cyclooctatetraenes (COTs) possess unique structural and electronic properties that originate from their saddle‐shaped π‐conjugated architectures. Considerable attention has been paid to the transition‐metal‐mediated synthesis of these cyclic compounds; however, there have been limited achievements to date in the efficient construction of heteroarene‐fused COTs. In this contribution, we report a novel Pd‐catalyzed dehydrogenative cyclodimerization of biheteroarenes through four‐fold C−H activation toward the synthesis of a series of heteroarene‐fused COTs. A set of mechanistic investigations indicated the involvement of high‐valent Pd species prior to the dimerization event in the catalytic cycle. The redox behavior of the obtained COTs is also described briefly.
Preparation of a new molecularly imprinted polymer based on self‐crosslinkable cellulose acrylate in aqueous solution: A drug delivery system for furosemide
Authors: Fareghi Amir Reza , Moghadam Peyman Najafi , Khalafy Jabbar , Bahram Morteza , Moghtader Mehdi
Published: August 2017

In the present study, a new, green, and biodegradable molecularly imprinted polymer (MIP) based on modified cellulose is introduced for the drug furosemide. First, microcrystalline cellulose was converted into cellulose acrylate (CA). Then the prepared CA underwent self‐crosslinking in the drug preassembly solution. The preassembly solution of the drug was also prepared using furosemide as the template molecule and acrylamide as the functional monomer in an aqueous medium. The results obtained from the binding and selectivity studies indicate the successful preparation of the CA‐based MIP (CA‐MIP) in aqueous solution. In the final step, an in vitro release study of furosemide from the synthesized polymers was carried out in a pH = 7.41 phosphate‐buffered saline solution at 37 °C. The drug release profiles showed that the release rate of the CA‐MIP is more controlled than that of the corresponding nonimprinted polymer, especially at the early stages of release. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45581.
Microcellular foaming of chlorosulfonated polyethylene rubber and its kaolin‐filled compounds with supercritical nitrogen
Authors: Zhang Zhen‐Xiu , Lang Xian‐Hua , Zhang Xin , Xin Zhenxiang , K Prakashan
Published: August 2017

The microcellular foaming of vulcanizates made from chlorosulfonated polyethylene (CSM) rubber and its kaolin‐filled compounds was carried out with supercritical nitrogen. The effects of various curing times, temperatures of the vulcanizates, and kaolin filler contents in the vulcanizates on the prepared foams were studied. The foaming of the vulcanizates with various crosslinking densities revealed the critical effect the crosslinking density of the CSM matrix played on its foaming. A certain sufficient level of crosslinking density was most effective for the foaming of the matrix; a higher crosslinking density led to a decreased cell size, increased cell density, and decreased matrix expansion in the foams. The effect of the crosslinking density was due to its effect on the free volume of the elastomeric matrix, which controlled the gas diffusion from the matrix during the pressure‐release stage of the foaming operation. The incorporation of kaolin decreased the cell size and increased the cell density of the foams; the decreased free volume and the heterogeneous cell nucleation effect of the kaolin contributed to this. The tensile strength of the foams significantly improved with increasing kaolin content in the foams. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45656.
Preparation of bromo‐substituted polyaniline with excellent antibacterial activity
Authors: Cai Wei , Wang Jixiao , Quan Xiaodong , Wang Zhi
Published: August 2017

Bromo‐substituted polyaniline (Br‐PANI) is prepared by a novel strategy in which PANI is used as raw material, potassium bromate and potassium bromide as brominate regents. The obtained Br‐PANI is characterized by scanning electron microscopy, X‐ray photoelectron spectroscopy, elemental analysis, FTIR, UV–vis spectra, and TGA. The results clearly indicate that Br has successfully attached to the benzene ring of PANI by chemical bond. The behavior of Br‐PANI toward bacteria is characterized by plate counting, minimal inhibitory concentration, and minimal bactericidal concentration methods. The experimental results indicate that both doped and dedoped Br‐PANIs have long‐term antibacterial activities as compared to doped/dedoped PANI. What's more, the antibacterial abilities increase with increasing the Br/N molar ratio of the Br‐PANI. Thus Br‐PANI should be a kind of efficient and environmentally friendly antibacterial agent. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45657.
Study on microfracture mechanism of short glass fiber reinforced polycarbonate by using acoustic emission
Authors: Kato Atsushi , Hamada Shinya , Shimizu Satoshi
Published: August 2017

The influence of the difference in wettability between glass fiber (GF) and polycarbonate (PC) on the microfractures of GF reinforced PC was investigated by using an acoustic emission (AE) method. In the case of well‐coupled GF‐reinforced PC, it is suggested that in the AE amplitude region higher than about 16 mV, microfracture related to scission of polymer chains occurs at the interfacial layer between GF and PC. On the other hand, in the case of poorly‐coupled GF‐reinforced PC under stress, debonding and interfacial slippage between GF and PC occurred below the yield stress of PC, whereas interfacial fracture and GF breakage occurred above the yield stress. Debonding and interfacial slippage between GF and the PC matrix were closely related to an AE amplitude smaller than about 16 mV. The relationship between stress and AE events is expressed in this case by the Eyring model. The activation energy of interfacial slippage between GF and PC was about 74 kJ/mol, which corresponds to the energy of chain‐backbone motion of PC in the glassy state. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45664.
Computertomografie – den Fasern auf der Spur
Authors: Schuler Frank , Breit Wolfgang , Schnell Jürgen , Schladitz Katja
Published: August 2017

Die bildanalytische Auswertung von 3‐D‐Computertomografieaufnahmen ermöglicht es, die Orientierung, Verteilung und Menge von Fasern in einem zu untersuchenden Betonkörper zu bestimmen.

Der folgende Bericht befasst sich mit der praktischen Anwendung dieses neuartigen Verfahrens zur Lösung typischer Fragestellungen des Bauingenieurwesens.

Die Analyse von aus Tunneltübbings entnommenen Bohrkernen zur Untersuchung des Einflusses der Herstellart auf die Orientierung und räumliche Verteilung der Fasern zeigt beispielhaft die Anwendungsmöglichkeiten des Verfahrens. Der Fokus der durchgeführten Arbeiten lag hierbei auf der Festlegung des anzusetzenden Faktors zur Berücksichtigung der Faserorientierung nach DAfStb‐Richtlinie „Stahlfaserbeton“.
Application of Dye‐coated Ultrasmall Gadolinium Oxide Nanoparticles for Biomedical Dual Imaging
Authors: Miao Xu , Xu Wenlong , Cha Hyunsil , Chang Yongmin , Oh In Taek , Chae Kwon Seok , Lee Gang Ho
Published: August 2017

Nanoparticles are very important in biomedical imaging because their imaging properties are superior to those of small molecules. They can be further functionalized for multimodal imaging through surface modification. In this study, we synthesized dye‐coated ultrasmall gadolinium oxide nanoparticles [dye = fluorescein and fluorescein isothiocyanate (FITC)] in one‐pot and investigated their dual imaging properties. The dye‐coated gadolinium oxide nanoparticles exhibited excellent relaxometric properties suitable for T1 magnetic resonance imaging (MRI): r1 = 9.8 s−1mM−1 (r2/r1 = 2.6) for fluorescein‐coated nanoparticles (davg = 1.6 ± 0.1 nm) and r1 = 12.3 s−1mM−1 (r2/r1 = 2.3) for FITC‐coated nanoparticles (davg = 1.4 ± 0.1 nm), and strong photoluminescence (PL) in the green region (around 514 nm) suitable for fluorescent imaging (FI). The dye‐coated nanoparticles exhibited strong fluorescence in cellular confocal images and high contrast in T1 MR images in mice, suggesting that they are potential dual T1 MRI‐FI agents.
Tread carefully when considering social media in admissions decisions
Authors: Porter Michael , Levy Nathaniel
Published: August 2017

Even though college students have used social media for more than a decade, there has been little legal guidance on whether or how institutions can consider social media in the admissions process.
Review answers to readers' questions about FERPA
Authors: Rainsberger Richard
Published: August 2017

In this column, I'll answer questions from readers about the Family Educational Rights and Privacy Act.
Was college liable for attack against a student?
Authors: Gelpi Aileen
Published: August 2017

John Mallett went into the offices of Miami‐Jacobs Business College and used a knife to attack Admissions Representative Gerald Dowe, for no apparent reason, in March 2012. Although he was stabbed several times, Dowe managed to render Mallett unconscious.
KLK14 interactions with HAI‐1 and HAI‐2 serine protease inhibitors: A molecular dynamics and relative free‐energy calculations study
Authors: Solís‐Calero Christian , Carvalho Hernandes F.
Published: August 2017

Kallikrein 14 (KLK14) is a serine protease linked to several pathologies including prostate cancer and positively correlates with Gleason score. Though KLK14 functioning in cancer is poorly understood, it has been implicated in HGF/Met signaling, given that KLK14 proteolytically inhibits HGF activator‐inhibitor 1 (HAI‐1), which strongly inhibits pro‐HGF activators, thereby contributing to tumor progression. In this work, KLK14 binding to either hepatocyte growth factor activator inhibitor type‐1 (HAI‐1) or type‐2 (HAI‐2) was essayed using homology modeling, molecular dynamic simulations and free‐energy calculations through MM/PBSA and MM/GBSA. KLK14 was successfully modeled. Calculated free energies suggested higher binding affinity for the KLK14/HAI‐1 interaction than for KLK14/HAI‐2. This difference in binding affinity is largely explained by the higher stability of the hydrogen‐bond networks in KLK14/HAI‐1 along the simulation trajectory. A key arginine residue in both HAI‐1 and HAI‐2 is responsible for their interaction with the S1 pocket in KLK14. Additionally, MM/GBSA free‐energy decomposition postulates that KLK14 Asp174 and Trp196 are hotspots for binding HAI‐1 and HAI‐2.
Tubulin acetylation accompanies autophagy development induced by different abiotic stimuli in Arabidopsis thaliana
Authors: Olenieva Vira , Lytvyn Dmytro , Yemets Alla , Bergounioux Catherine , Blume Yaroslav
Published: August 2017

Microtubules (MTs) play an important role in the regulation of autophagy development in yeast and animal as well as in plant cells. MTs participate in maturation and traffic of autophagosomes through their dynamic state changes and post‐translational modifications of tubulin, namely acetylation. We subjected Arabidopsis thaliana seedlings to metabolic‐, salt‐, osmotic stresses as well as irradiation of ultraviolet B and investigated the involvement of plant MTs in the development of stress‐induced autophagy via tubulin acetylation. For this purpose Arabidopsis thaliana line expressing autophagy‐related protein 8 h (atg8h)‐GFP was generated to investigate autophagy, applying the level of free GFP as an indicator of autophagy development. Using autophagosome confocal imaging and Western blot analysis of Atg8 post‐translational lipidation and synchronous GFP release it was shown that all examined stressful stimuli led to pronounced development of autophagy, particularly in different root tissues. Moreover, autophagy development was accompanied by α‐tubulin acetylation under all stressful conditions. Presented data indicate the possible role of the post‐translational acetylation of α‐tubulin in the mediation of plant stress‐induced autophagy.
Porcine spermatogonial stem cells self‐renew effectively in a three dimensional culture microenvironment
Authors: Park Ji Eun , Park Min Hee , Kim Min Seong , Park Yeo Reum , Yun Jung Im , Cheong Hee Tae , Kim Minseok , Choi Jung Hoon , Lee Eunsong , Lee Seung Tae
Published: August 2017

Generally, self‐renewal of spermatogonial stem cells (SSCs) is maintained in vivo in a three‐dimensional (3D) microenvironment consisting of the seminiferous tubule basement membrane, indicating the importance of the 3D microenvironment for in vitro culture of SSCs. Here, we report a 3D culture microenvironment that effectively maintains porcine SSC self‐renewal during culture. Porcine SSCs were cultured in an agarose‐based 3D hydrogel and in 2D culture plates either with or without feeder cells. Subsequently, the effects of 3D culture on the maintenance of undifferentiated SSCs were identified by analyzing cell colony formation and morphology, AP activity, and transcriptional and translational regulation of self‐renewal‐related genes and the effects on proliferation by analyzing cell viability and single cell‐derived colony number. The 3D culture microenvironment constructed using a 0.2% (w/v) agarose‐based 3D hydrogel showed the strongest maintenance of porcine SSC self‐renewal and induced significant improvements in proliferation compared with 2D culture microenvironments. These results demonstrate that self‐renewal of porcine SSCs can be maintained more effectively in a 3D than in a 2D culture microenvironment. Moreover, this will play a significant role in developing novel culture systems for SSCs derived from diverse species in the future, which will contribute to SSC‐related research.
Gitelman syndrome: a rare life‐threatening case of hypokalemic paralysis mimicking Guillain–Barré syndrome during pregnancy and review of the literature
Authors: Elkoundi Abdelghafour , Kartite Noureddine , Bensghir Mustapha , Doghmi Nawfal , Lalaoui Salim Jaafar
Published: August 2017

Key Clinical Message

In rare cases, patients with Gitelman syndrome may present with hypokalemic paralysis mimicking Guillain–Barré syndrome. The severity of resultant symptoms may be life‐threatening. Controversial drugs such as aldactone, amiloride, and eplerenone should be used in this situation despite the lack of safety data.
Aortic stent graft placement under extracorporeal membrane oxygenation in severe multiple trauma
Authors: Stroehle Mathias , Lederer Wolfgang , Schmid Stefan , Glodny Bernhard , Chemelli Andreas P. , Wiedermann Franz J.
Published: August 2017

Key Clinical Message

Placement of an aortic stent graft under extracorporeal membrane oxygenation was the life‐saving procedure in a case of severe head trauma and traumatic aortic dissection after injured by a railroad engine. Timely access to neurosurgery, heart surgery, and radiology providing minimal invasive interventions increase the chances of a favorable outcome.
Mechanism of Carbon Monoxide Dissociation on a Cobalt Fischer–Tropsch Catalyst
Authors: Chen Wei , Zijlstra Bart , Filot Ivo A. W. , Pestman Robert , Hensen Emiel J. M.
Published: August 2017

The way in which the triple bond in CO dissociates, a key reaction step in the Fischer–Tropsch (FT) reaction, is a subject of intense debate. Direct CO dissociation on a Co catalyst was probed by 12C16O/13C18O scrambling in the absence and presence of H2. The initial scrambling rate without H2 was significantly higher than the rate of CO consumption under CO hydrogenation conditions, which indicated that the surface contained sites sufficiently reactive to dissociate CO without the assistance of H atoms. Only a small fraction of the surface was involved in CO scrambling. The minor influence of CO scrambling and CO residence time on the partial pressure of H2 showed that CO dissociation was not affected by the presence of H2. The positive H2 reaction order was correlated to the fact that the hydrogenation of adsorbed C and O atoms was slower than CO dissociation. Temperature‐programmed in situ IR spectroscopy underpinned the conclusion that CO dissociation does not require H atoms.
Transfer Functions for Periodic Reactor Operation: Fundamental Methodology for Simple Reaction Networks
Authors: Meyer Dominik , Friedland Jens , Kohn Thiemo , Güttel Robert
Published: August 2017

A method for frequency response analysis of chemical reactors with periodically modulated inlet concentration is presented and demonstrated for simple first‐order irreversible consecutive and parallel as well as reversible reactions applying an isothermal continuous stirred‐tank reactor (CSTR). The frequency response of these reaction types is studied by simulations in time and frequency domain, the latter being based on Laplace transformation of the material balance. The results allow for clearly distinguish between the quasi and relaxed steady state as well as the full transient region with impact on designing reactors for dynamic operation. Furthermore, the relation between the dynamic response and the time constants of the system is discussed.
A Novel Approach for Measuring Gas Solubility in Liquids Using a Tube‐in‐Tube Membrane Contactor
Authors: Wu Gaowei , Cao Enhong , Kuhn Simon , Gavriilidis Asterios
Published: August 2017

A novel approach using a semipermeable Teflon AF‐2400 tube‐in‐tube membrane contactor was developed for the measurement of gas solubility in organic solvents. This membrane ensures gas saturation of liquids in continuous flow at a specific pressure and temperature. After liquid decompression, the amount of gas outgassed was measured with a bubble meter and used for solubility calculation. The proposed method was applied to the measurement of oxygen solubility in toluene and benzyl alcohol. Validation experiments were initially performed by comparing the obtained oxygen solubility in toluene with literature data. With higher temperature, the solubility of oxygen in benzyl alcohol was found to increase, indicating that the oxygen‐dissolving process is endothermic. Finally, an empirical correlation of Henry's law constant as a function of temperature was determined.
Molecular Dynamics Insights into Polyamine–DNA Binding Modes: Implications for Cross‐Link Selectivity
Authors: Bignon Emmanuelle , Chan Chen‐Hui , Morell Christophe , Monari Antonio , Ravanat Jean‐Luc , Dumont Elise
Published: August 2017

Biogenic polyamines, which play a role in DNA condensation and stabilization, are ubiquitous and are found at millimolar concentration in the nucleus of eukaryotic cells. The interaction modes of three polyamines—putrescine (Put), spermine (Spm), and spermidine (Spd)—with a self‐complementary 16 base pair (bp) duplex, are investigated by all‐atom explicit‐solvent molecular dynamics. The length of the amine aliphatic chain leads to a change of the interaction mode from minor groove binding to major groove binding. Through all‐atom dynamics, noncovalent interactions that stabilize the polyamine–DNA complex and prefigure the reactivity, leading to the low‐barrier formation of deleterious DNA–polyamine cross‐links, after one‐electron oxidation of a guanine nucleobase, are unraveled. The binding strength is quantified from the obtained trajectories by molecular mechanics generalized Born surface area post‐processing (MM‐GBSA). The values of binding free energies provide the same affinity order, Put<Spm<Spd, as that determined by recent isothermal calorimetry measurements, with a satisfactory correlation, to validate the structural predictions. The binding modes and carbon–nitrogen distances along the series of polyamines illustrate the selectivity towards deleterious DNA–polyamine cross‐link formation through the extraction of average approaching distances between the C8 atom of guanines and the ammonium group. These results imply that the formation of DNA–polyamine cross‐links involves deprotonation of the guanine radical cation to attack the polyamines, which must be positively charged to lie in the vicinity of the B‐helix.
Excitonically Coupled States in Crystalline Coordination Networks
Authors: Haldar Ritesh , Mazel Antoine , Joseph Reetu , Adams Michael , Howard Ian A. , Richards Bryce S. , Tsotsalas Manuel , Redel Engelbert , Diring Stéphane , Odobel Fabrice , Wöll Christof
Published: August 2017

When chromophores are brought into close proximity, noncovalent interactions (π–π/CH–π) can lead to the formation of excitonically coupled states, which bestow new photophysical properties upon the aggregates. Because the properties of the new states not only depend on the strength of intermolecular interactions, but also on the relative orientation, supramolecular assemblies, where these parameters can be varied in a deliberate fashion, provide novel possibilities for the control of photophysical properties. This work reports that core‐substituted naphthalene diimides (cNDIs) can be incorporated into surface‐mounted metal– organic structures/frameworks (SURMOFs) to yield optical properties strikingly different from conventional aggregates of such molecules, for example, formed in solution or by crystallization. Organic linkers are used, based on cNDIs, well‐known organic chromophores with numerous applications in different optoelectronic devices, to fabricate MOF thin films on transparent substrates. A thorough characterization of the properties of these highly ordered chromophoric assemblies reveals the presence of non‐emissive excited states in the crystalline material. Structural modulations provide further insights into the nature of the coupling that gives rise to an excited‐state energy level in the periodic structure.
Potassium (De‐)insertion Processes in Prussian Blue Particles: Ensemble versus Single Nanoparticle Behaviour
Authors: Zampardi Giorgia , Sokolov Stanislav V. , Batchelor‐McAuley Christopher , Compton Richard G.
Published: August 2017

Potassium (de‐)insertion from Prussian blue (PB) is investigated at the single and multi‐particle scale. The electrochemical behaviour is found to differ between the two measurement types. At the single particle level, oxidation of the PB nanoparticles with concomitant K+ deinsertion occurs more readily than the associated reduction, relating to K+ insertion. In contrast, the cyclic voltammetry of PB in a composite electrode containing conductive additives and polymeric binder suggests the opposite behaviour. Implications for assessing battery materials are discussed.