bluuebunny/crossref_metadata_2025 huggingface dataset:
Nucleation and Crystallization Control via Polyurethane to Enhance the Bendability of Perovskite Solar Cells with Excellent Device Performance
Authors: Huang Zengqi , Hu Xiaotian , Liu Cong , Tan Licheng , Chen Yiwang
Published: September 2017

Solar cells based on mixed organic–inorganic halide perovskites are promising photovoltaic technologies with low‐cost and fantastic power conversion efficiency (PCE). Enhancing the nucleation and regulating the crystallization rate of perovskite films and improving the bendability of brittle hybrid grains are crucial to improving the photovoltaic performance of flexible perovskite solar cells (PVSCs). Here, a simple approach is first introduced for fabricating perovskite films with full coverage and larger crystalline size by incorporating the elastomer polyurethane (PU) into the perovskite precursor solution to both retard the crystallization rate and improve the bendability. Shiny, smooth perovskite films are obtained with compact, micrometer‐sized crystalline grains that exhibit excellent photoelectric performances. The PVSCs fabricated by incorporating PU into the perovskite precursor offer an impressive PCE of 18.7% with almost no photocurrent hysteresis and excellent stability in ambient air. More importantly, the elastomer PU additive crosslinks the grain boundaries between neighboring perovskite crystals to form a PU network that effectively improves the bendability of the perovskite films.
Phenotypic Selection of Magnetospirillum magneticum (AMB‐1) Overproducers Using Magnetic Ratcheting
Authors: Tay Andy , Murray Coleman , Di Carlo Dino
Published: September 2017

Magnetosomes, magnetic nanoparticles (MNPs) encapsulated in lipid membranes produced by magnetotactic bacteria (MTB), have superior properties such as a narrow size distribution, making them of potential significant value for biomedical and industrial applications. However, the slow growth rate and genetic complexity of MTB have thus far limited large scale production of biologically synthesized MNPs. This problem is compounded by a lack of a platform to select MTB of interest. Here, the development of a magnetic ratcheting system that facilitates automated, live, and quantitative isolation of Magnetospirillum magneticum (AMB‐1) based on their phenotype, i.e., number of MNPs is described. Using repeated (five) cycles of random chemical mutagenesis and magnetic selection, AMB‐1 overproducers that biomineralize on average 2.2‐fold more MNPs (≈25) than the widely available strain AMB‐1 are generated. The size, shape, and magnetic properties of the MNPs of the overproducers are also similar to the control AMB‐1, supporting the utility of the platform for enriching MTB with overproducer phenotypes.
Ultrahigh‐Efficiency Green PHOLEDs with a Voltage under 3 V and a Power Efficiency of Nearly 110 lm W−1 at Luminance of 10 000 cd m−2
Authors: Zhang Dongdong , Qiao Juan , Zhang Deqiang , Duan Lian
Published: September 2017

Maintaining high power efficiency (PE) under high brightness is still a pressing problem for the practical application of organic light‐emitting diodes (OLEDs). Here, ultrahigh‐efficiency green phosphorescent OLEDs (PHOLEDs) with a record‐low voltage at luminance above 5000 cd m−2 are fabricated, by developing a novel anthracene/pyridine derivative as the electron‐transporting material (ETM) combined with a material displaying thermally activated delayed fluorescence as the host. The pyridine units of the ETM not only facilitate charge injection, but also enhance the electron‐transporting mobility, profiting from the closely packed molecules caused by the intermolecular H‐bonding. The optimized green PHOLEDs show record‐low driving voltages of 2.76 and 2.92 V, with EQEs/PEs of 28.0%/102 lm W−1 and 27.9%/97 lm W−1 at 5000 and 10 000 cd m−2, respectively. Furthermore, device optimization exhibits an unprecedented high PE of 109 lm W−1 at 10 000 cd m−2 with voltage under 3 V. Those values are the state‐of‐the‐art among all reported green OLEDs so far, paving their way toward practical applications.
Electrochemical co‐deposition and characterization of polyaniline and manganese oxide nanofibrous composites for energy storage properties
Authors: Shah Anwar‐ul‐Haq Ali , Khan Muhammad Owais , Bilal Salma , Rahman Gul , Hoang Hung Van
Published: September 2017

Ion diffusion rate and contact surface area of conducting polymers increased by composite formation with nanometric‐size materials make them promising materials in the fabrication of energy storage devices. In this work, electronically conducting polyaniline and manganese oxide (PANI/MnO2) nanofibrous composites were electrochemically co‐deposited on stainless steel from binder‐free electrolyte solution. Structural characterization and morphological characterization of the materials were performed with Fourier‐transformed infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). SEM images show fibrous micro/nano‐architecture of the composites with cluster networking structure having 200–500 nm length and 100–200 nm diameter. Electrochemical and energy storage properties of the as‐synthesized materials were investigated with cyclic voltammetry (CV), galvanostatic charge discharge curves(GCDC), and potentiostatic electrochemical impedance spectroscopy (PEIS) without any binders. Electrochemical measurements as well as galvanostatic charge discharge curves at 1 mA constant current have shown maximum specific capacitance of 149 F/g for the composite prepared with 0.15 M MnSO4 in the co‐deposition bath. The composites retain 67% specific capacitance even after 400 cycles, indicating the stability of synthesized composite. PEIS confirms the pseudocapacitive nature of the synthesized composites.
Rod‐Shaped Active Drug Particles Enable Efficient and Safe Gene Delivery
Authors: Xin Xiaofei , Pei Xue , Yang Xin , Lv Yaqi , Zhang Li , He Wei , Yin Lifang
Published: September 2017

Efficient microRNAs (miRNA) delivery into cells is a promising strategy for disease therapy, but is a major challenge because the available conventional nonviral vectors have significant drawbacks. In particular, after these vectors are entrapped in lysosomes, the escape efficiency of genes from lysosomes into the cytosol is less than 2%. Here, a novel approach for lethal‐7a (let‐7a) replacement therapy using rod‐shaped active pure drug nanoparticles (≈130 nm in length, PNPs) with a dramatically high drug‐loading of ≈300% as vectors is reported. Importantly, unlike other vectors, the developed PNPs/let‐7a complexes (≈178 nm, CNPs) can enter cells and bypass the lysosomal route to localize to the cytosol, achieving efficient intracellular delivery of let‐7a and a 50% reduction in expression of the target protein (KRAS). Also, CNPs prolong the t1/2 of blood circulation by ≈threefold and increase tumor accumulation by ≈1.5–2‐fold, resulting in significantly improved antitumor efficacies. Additionally, no damage to normal organs is observed following systemic injection of CNPs. In conclusion, rod‐shaped active PNPs enable efficient and safe delivery of miRNA with synergistic treatment for disease. This nanoplatform would also offer a viable strategy for the potent delivery of proteins and peptides in vitro and in vivo.
The impact of asthma on the cost effectiveness of surgery for chronic rhinosinusitis with nasal polyps
Authors: Scangas George A. , Remenschneider Aaron K. , Su Brooke M. , Shrime Mark G. , Metson Ralph
Published: September 2017

Background

The objective of this work was to evaluate the impact of asthma on the cost‐effectiveness profile of endoscopic sinus surgery (ESS) compared to medical therapy for patients with chronic rhinosinusitis with nasal polyps (CRSwNP).

Methods

The study design consisted of a cohort‐style Markov decision‐tree cost utility analysis with a 35‐year time horizon. Matched cohorts of CRSwNP patients with (n = 95) and without (n = 95) asthma who underwent ESS were compared with cohorts of patients from the national Medical Expenditures Survey Panel (MEPS) database who underwent medical management for chronic rhinosinusitis (CRS). Baseline, 1‐year, and 2‐year health utility values were calculated from responses to the EuroQol‐5 Dimension (EQ‐5D) instrument in both cohorts. The primary outcome measure was the incremental cost effectiveness ratio (ICER) for each cohort.

Results

The reference cases for CRSwNP patients with and without asthma yielded ICERs for ESS vs medical therapy alone of $12,066 per quality‐adjusted life year (QALY) and $7,369 per QALY, respectively. At a willingness‐to‐pay threshold of $50,000/QALY, the ICER scatter plots demonstrated 86% and 99% certainty that the ESS strategy was the most cost‐effective option for CRSwNP patients with and without asthma, respectively. ESS was not significantly more cost effective for CRSwNP patients without asthma (p = 0.494).

Conclusion

ESS remains cost effective compared to medical therapy for patients both with and without asthma. While the comorbidity of asthma results in an inferior ICER result, it does not result in a statistically significant negative impact on the overall cost effectiveness of ESS.
Robin Boundary Condition for Casimir Plates in a General Weak Gravitational Field
Authors: Nazari Borzoo
Published: September 2017

The energy of the massless scalar field inside parallel Casimir plates in a general weak gravitational field under the influence of Robin boundary conditions is calculated. The mode frequencies are found in asymptotic limits and consistency of results with the literature is shown. Experimental evidence for detection of corrections is explored.
Enantioselective Catalysis Coupled with Stereodivergent Cyclization Strategies Enables Rapid Syntheses of (+)‐Limaspermidine and (+)‐Kopsihainanine A
Authors: Pritchett Beau P. , Donckele Etienne J. , Stoltz Brian M.
Published: September 2017

Enantioselective Pd‐catalyzed allylic alkylations of dihydropyrido[1,2‐a]indolone (DHPI) substrates were used to construct the C20‐quaternary stereocenters of multiple monoterpene indole alkaloids. Stereodivergent Pictet–Spengler and Bischler–Napieralski cyclization/reduction cascades furnish the cis‐ and trans‐fused azadecalin subunits present in Aspidosperma and Kopsia alkaloids, respectively, en route to highly efficient syntheses of (+)‐limaspermidine and (+)‐kopsihainanine A.
Metal‐Free Boron‐Containing Heterogeneous Catalysts
Authors: Fang Yuanxing , Wang Xinchen
Published: September 2017

Metal‐free catalysts have distinct advantages over metal and metal oxide catalysts, such as lower cost as well as higher reliability and sustainability. Among the nonmetal compounds used in catalysis, boron‐containing compounds with a few unique properties have been developed. In this Minireview, the recent advances in the field of boron‐containing metal‐free catalysts are presented, including binary and ternary boron‐containing catalytic materials. Additionally, the three main applications in catalysis are considered, namely, electrocatalysis, thermal catalysis, and photocatalysis, with the role of boron discussed in depth for each specific catalytic application. Boron‐containing compounds could have a substantial impact on the field of metal‐free catalysts in the future.
A Nonsmooth Nonlinear Programming Based Predictive Control for Mechanical Servo Systems with Backlash‐like Hysteresis
Authors: Dong Ruili , Tan Qingyuan , Tan Yonghong
Published: September 2017

In this paper, a multi‐step‐ahead predictive control approach for dynamic systems with preceded backlash‐like hysteresis based on nonsmooth nonlinear programming is proposed. In this approach, a nonsmooth multi‐step‐ahead predictive model is developed for long‐range prediction of the controlled dynamic systems with preceded backlash‐like hysteresis. Then, the predictive control strategy is treated as a problem of on‐line nonsmooth nonlinear programming. Subsequently, the stability of the nonsmooth predictive control system is analyzed and the corresponding stability condition is derived. Afterward, a numerical example and a simulation based on a mechanical servo system are presented, respectively.
Enhancement of l‐phenylalanine production in Escherichia coli by heterologous expression of Vitreoscilla hemoglobin
Authors: Wu Wei‐Bin , Guo Xiao‐Lei , Zhang Ming‐Liang , Huang Qing‐Gen , Qi Feng , Huang Jian‐Zhong
Published: September 2017

l‐Phenylalanine is an important amino acid that is widely used in the production of food flavors and pharmaceuticals. Generally, l‐phenylalanine production by engineered Escherichia coli requires a high rate of oxygen supply. However, the coexpression of Vitreoscilla hemoglobin gene (vgb), driven bya tac promoter, with the genes encoding 3‐deoxy‐d‐arabinoheptulosonate‐7‐phosphate synthetase (aroF) and feedback‐resistant chorismate mutase/prephenate dehydratase (pheAfbr), led to increased productivity and decreased demand for aeration by E. coli CICC10245. Shake‐flask studies showed that vgb‐expressing strains displayed higher rates of oxygen uptake, and l‐phenylalanine production under standard aeration conditions was increased. In the aerobic fermentation process, cell growth, l‐phenylalanine production, and glucose consumption by the recombinant E. coli strain PAPV, which harbored aroF, pheAfbr, and tac‐vgb genes, were increased compared to that in the strain harboring only aroF and pheAfbr (E. coli strain PAP), especially under oxygen‐limited conditions. The vgb‐expressing strain PAPV produced 21.9% more biomass and 16.6% more l‐phenylalanine, while consuming only approximately 5% more glucose after 48 H of fermentation. This study demonstrates a method to enhance the l‐phenylalanine production by E. coli using less intensive and thus more economical aeration conditions.
The Hidden Cost of Insurance on Cooperation
Authors: van de Calseyde Philippe P.F.M. , Keren Gideon , Zeelenberg Marcel
Published: September 2017

A common solution to mitigate risk is to buy insurance. Employing the trust game, we find that buying insurance against the risk of betrayal has a hidden cost: trustees are more likely to act opportunistically when trustors choose to be insured against the breach of trust. Supposedly, trustees are less likely to cooperate when trustors buy insurance because choosing insurance implicitly signals that the trustor expects the trustee to behave opportunistically, paradoxically encouraging trustees not to cooperate. These results shed new light on the potential drawbacks of financial safeguards that are intended to minimize the risky nature of trust taking: the presumed safeguard against the risk of betrayal may, under certain circumstances, increase the probability of betrayal. Copyright © 2017 John Wiley & Sons, Ltd.
Characterization of ectonucleoside triphosphate diphosphohydrolase (E‐NTPDase; EC 3.6.1.5) activity in mouse peritoneal cavity cells
Authors: Dias Dhébora Albuquerque , de Barros Penteado Bruna , dos Santos Lucas Derbocio , dos Santos Pedro Mendes , Arruda Carla Cardozo Pinto , Schetinger Maria Rosa Chitolina , Leal Daniela Bitencourt Rosa , dos Santos Jaques Jeandre Augusto
Published: September 2017

This study aimed to characterize the activity of ectonucleoside triphosphate diphosphohydrolase (E‐NTPDase; EC 3.6.1.5) in peritoneal cavity cells from BALB/c mice. E‐NTPDase was activated in the presence of both calcium (1.5mM) and magnesium (1.5mM) ions. However, the activity was higher in the presence of Ca2+. A pH of 8.5 and temperature of 37°C were the optimum conditions for catalysis. The apparent Km values were 0.51mM and 0.66mM for the hydrolysis of adenosine triphosphate (ATP) and adenosine diphosphate (ADP), respectively. The Vmax values were 136.4 and 120.8 nmol Pi/min/mg of protein for ATPase and ADPase activity, respectively. Nucleotide hydrolysis was inhibited in the presence of sodium azide (20mM, ATP: P < .05; ADP: P < .001), sodium fluoride (20mM; ATP and ADP: P < .001), and suramin (0.3mM; ATP: P < .01; ADP: P < .05), which is a known profile for NTPDase inhibition. Although all of the diphosphate and triphosphate nucleotides that were tested were hydrolyzed, enzyme activity was increased when adenine nucleotides were used as substrates. Finally, we stress that knowledge of the E‐NTPDase catalytic biochemical properties in mouse peritoneal cavity cells is indispensable for properly determining its activity, as well as to fully understand the immune response profile in both healthy and sick cells.
Activation of the mitochondrial apoptotic pathway contributes to methotrexate‐induced small intestinal injury in rats
Authors: Natarajan Kasthuri , Abraham Premila , Kota Rekha
Published: September 2017

The efficacy of methotrexate (MTX), a commonly used chemotherapeutic drug, is limited by intestinal injury. As the mechanism of MTX‐induced small intestinal injury is not clear, there is no definitive treatment for MTX‐induced gastrointestinal injury. The present study investigates the role of mitochondrial apoptotic pathway in MTX‐induced small intestinal injury and examines whether aminoguanidine is effective in preventing the damage. Eight Wistar rats were administered 3 consecutive i.p. injections of 7 mg/kg body wt. MTX. Some rats were pretreated with 30 mg or 50 mg/kg body wt. of aminoguanidine (n = 6 in each group). Protein expressions of cytochrome c, caspases 3 and 9, and PARP‐1 were determined in the small intestines by immunohistochemistry and western blot. Mitochondrial pathway of apoptosis was activated in the small intestines of MTX‐treated rats as evidenced by intense immunostaining for cyt c, caspases 9 and 3, and PARP‐1 and mitochondrial release of cyt c, activation of caspases, and PARP‐1 cleavage by Western blot. Immunofluorescence revealed increased nuclear localization of PARP‐1. Aminoguanidine pretreatment ameliorated MTX‐induced small intestinal injury in dose‐dependent manner and inactivated the mitochondrial apoptotic pathway. Aminoguanidine may possess beneficial intestinal protective effects as an adjuvant co‐drug against MTX intestinal toxicity during cancer chemotherapy. As the mechanism of MTX‐induced small intestinal injury is not clear, there is no definitive treatment for MTX‐induced gastrointestinal injury. The results of the present study show that the mitochondrial pathway of apoptosis plays a role in MTX‐induced small intestinal injury as evidenced by cytochrome c release, activation of caspases 9 and 3, PARP‐1 cleavage, and DNA fragmentation. Aminoguanidine (AG) pretreatment attenuates the severity of small‐intestinal injury induced in rats by MTX treatment. The mechanisms of action of AG involve inhibition of iNOS, and mitochondrial pathway of apoptosis. It is suggested that aminoguanidine may possess beneficial intestinal protective effects as an adjuvant co‐drug against MTX intestinal toxicity during cancer chemotherapy.
Visualizing the Adenylation Activities and Protein–Protein Interactions of Aryl Acid Adenylating Enzymes
Authors: Ishikawa Fumihiro , Kasai Shota , Kakeya Hideaki , Tanabe Genzoh
Published: September 2017

Structural and activity studies have revealed the dynamic and transient actions of carrier protein (CP) activity in primary and secondary metabolic pathways. CP‐mediated interactions play a central role in nonribosomal peptide biosynthesis, as they serve as covalent tethers for amino acid and aryl acid substrates and enable the growth of peptide intermediates. Strategies are therefore required to study protein–protein interactions efficiently. Herein, we describe activity‐based probes used to demonstrate the protein–protein interactions between aryl CP (ArCP) and aryl acid adenylation (A) domains as well as the substrate specificities of the aryl acid A domains. If coupled with in‐gel fluorescence imaging, this strategy allows visualization of the protein–protein interactions required to recognize and transfer the substrate to the partner ArCP. This technique has potential for the analysis of protein–protein interactions within these biosynthetic enzymes at the molecular level and for use in the combinatorial biosynthesis of new nonribosomal peptides.
Metal–Organic Framework Mediated Synthesis of Small‐Sized γ‐Alumina as a Highly Active Catalyst for the Dehydration of Glycerol to Acrolein
Authors: Huang Liang , Qin Feng , Huang Zhen , Zhuang Yan , Ma Jianxue , Xu Hualong , Shen Wei
Published: September 2017

The dehydration of glycerol into acrolein was investigated over small‐sized γ‐Al2O3 prepared by a metal–organic framework (MOF) templated method. The particle size of alumina strongly affected the final physicochemical properties of γ‐Al2O3 as well as its catalytic activity. The MOF‐derived, small‐sized γ‐Al2O3 (M‐Al2O3) catalyst exhibited higher stability and higher activity in the glycerol dehydration reaction than conventional bulk γ‐Al2O3 and nanorod γ‐Al2O3 owing to enriched intercrystal mesopores and an abundance of accessible acid sites. M‐Al2O3 retained its high glycerol conversion (over 80 %) for nearly 200 h, whereas high acrolein selectivity (74 %) was achieved.
Nanohybrids of Two‐Dimensional Transition‐Metal Dichalcogenides and Titanium Dioxide for Photocatalytic Applications
Authors: Rahmanian Elham , Malekfar Rasoul , Pumera Martin
Published: September 2017

The ever increasing need for renewable and clean energy resources as well as environmental concerns are considered as two serious challenges of today's society. Photocatalysis has proved to be a reliable and effective technology to overcome these issues. However, to bring the full potential of this approach into reality, two main hurdles of fast charge recombination and the limited visible light absorption should be tackled. To address these obstacles, nanocomposites based on titanium dioxide nanostructures and semiconducting two‐dimensional transition‐metal dichalcogenides have been developed and proven to be excellent photocatalysts. In this review, we will overview the recent developments on the fabrication and rational design of these nanocomposites both for hydrogen production and photocatalytic degradation of pollutants with emphasis on those appealing structures.
Gas Adsorption Studies of CO2 in Carbon Nanomaterials: A Case Study of Vertically Aligned Carbon Nanotubes
Authors: Babu Deepu J. , Schneider Jörg J.
Published: September 2017

With their well‐defined pore structure and chemical composition, vertically aligned carbon nanotubes (VACNTs) offer the possibility for a combined theoretical and experimental investigation of their gas adsorption behavior. Due to their nearly ideal 1D structure they offer a defined morphology in which a variety of structural parameters can be tailored. Subsequently the influence of curvature, packing density, adsorption site topology, inner and outer adsorptive surface as well as the influence of functional groups/heteroatoms on CO2 adsorption characteristics can be studied.
Scale‐up of the Synthesis of Zeolitic Imidazolate Framework ZIF‐4
Authors: Hovestadt Maximilian , Vargas Schmitz Jürgen , Weissenberger Tobias , Reif Florian , Kaspereit Malte , Schwieger Wilhelm , Hartmann Martin
Published: September 2017

A new synthesis route for the zeolitic imidazolate framework ZIF‐4 is reported. About 200 g of ZIF‐4 are prepared by sonothermal synthesis from ZnO at room temperature. The ZIF‐4 prepared by sonothermal synthesis is comparable to the ZIF‐4 synthesized by the pathway reported in literature with respect to the powder X‐ray diffraction pattern, particle size, and separation potential for olefin‐paraffin gas mixtures. Moreover, the separation potential of ZIF‐4 is compared to commercial adsorbents like carbon molecular sieves and zeolites.
OLED Reloaded: Die Synthese des Halbleiterpolymers MEH‐PPV als Schulversuch
Authors: Banerji Amitabh , Schönbein Ann‐Kathrin , Wolff Johanna
Published: September 2017

Organische Leuchtdioden (OLEDs) sind moderne Leuchtmittel der nächsten Generation. Sie verwenden (u. a.) halbleitende Polymere für die Lichtemission und erschließen völlig neuartige Anwendungsgebiete wie flexible oder transparente Displays und Leuchten. Für die Implementation von OLEDs in den Chemieunterricht wurden bereits low‐cost Experimente und Lehr‐Lern‐Materialien bereitgestellt. Dieser Beitrag erweitert das Thema um die Synthese eines Halbleiterpolymers im Schulversuch und präsentiert ein gelungenes Beispiel für die curriculare Innovation durch die Kooperation zwischen der Fachdidaktik und Fachwissenschaft.
Lebensmittel natürlich oder technologisch verändert? – Beispiele einer Kooperation zwischen Schule und Hochschule zum Kontext Lebensmitteltechnologie
Authors: Wentorf Wilfried , Keppler Julia K. , Knipp Jörg R. , Parchmann Ilka , Schwarz Karin
Published: September 2017

Dieser Artikel zeigt anhand der Lebensmitteltechnologie Beispiele für die direkte Kooperation von Fachwissenschaft, Schule und Didaktik bei der Erschließung und Ausgestaltung neuer Unterrichtskonzepte und Unterrichtsmaterialien. Die Erforschung von Molkenproteinen als mögliche „Nanotransporter“ in Lebensmitteln wird als Unterrichtsgang anhand konkreter Arbeitsblätter vorgestellt. Dabei erhalten Schülerinnen und Schüler gleichzeitig Einblicke in das vielschichtige Tätigkeitsfeld von Naturwissenschaftlerinnen und Naturwissenschaftlern, wie es das Konstrukt „Nature of Scientists“ vorsieht.
Redox‐Flow‐Batterien – Organische Batterien mit Zukunftsperspektiven
Authors: Rosenberg Dominique , Pansegrau Svenja , Wachholz Mirco , Rehling Alexander , Busker Maike , Jansen Walter
Published: September 2017

Redox‐Flow‐Batterien auf Basis von Vanadium‐Verbindungen werden derzeit als Energiespeicher erprobt, um im Rahmen des Ausbaus der erneuerbaren Energien entstehende Einspeisespitzen und Nachfrageschwankungen zu kompensieren. Vanadium‐Verbindungen sind aufgrund ihrer Toxizität für den Chemieunterricht nicht geeignet. Um dieses Thema für den Chemieunterricht zur erschließen, werden in Anlehnung an die Arbeiten der Arbeitsgruppen um Aziz und Narayanan Experimente unter Verwendung von Hydrochinonen und Chinonen entwickelt. In diesem Artikel werden grundlegende Versuche, in denen auf die Arbeiten von Aziz und Narayanan eingegangen wird, präsentiert sowie organische Batterien unter der Verwendung von Alltagsmaterialien vorgestellt.
Uremic pericarditis, pericardial effusion, and constrictive pericarditis in end‐stage renal disease: Insights and pathophysiology
Authors: Rehman Karim Abdur , Betancor Jorge , Xu Bo , Kumar Arnav , Rivas Carlos Godoy , Sato Kimi , Wong Leslie P. , Asher Craig R. , Klein Allan L.
Published: September 2017

A rising prevalence of end‐stage renal disease (ESRD) has led to a rise in ESRD‐related pericardial syndromes, calling for a better understanding of its pathophysiology, diagnoses, and management. Uremic pericarditis, the most common manifestation of uremic pericardial disease, is a contemporary problem that calls for intensive hemodialysis, anti‐inflammatories, and often, drainage of large inflammatory pericardial effusions. Likewise, asymptomatic pericardial effusions can become large and impact the hemodynamics of patients on chronic hemodialysis. Constrictive pericarditis is also well documented in this population, ultimately resulting in pericardiectomy for definitive treatment. The management of pericardial diseases in ESRD patients involves internists, cardiologists, and nephrologists. Current guidelines lack clarity with respect to the management of pericardial processes in the ESRD population. Our review aims to describe the etiology, classification, clinical manifestations, diagnostic imaging tools, and treatment options of pericardial diseases in this population.
Selective and Efficient Iridium Catalyst for the Reductive Amination of Levulinic Acid into Pyrrolidones
Authors: Wang Shengdong , Huang Haiyun , Bruneau Christian , Fischmeister Cédric
Published: September 2017

The catalytic reductive amination of levulinic acid (LA) into pyrrolidones with an iridium catalyst using H2 as hydrogen source is reported. The chemoselective iridium catalyst displayed high efficiency for the synthesis of a variety of N‐substituted 5‐methyl‐2‐pyrrolidones and N‐arylisoindolinones. N‐Substituted 5‐methyl‐2‐pyrrolidone was also evaluated as a biosourced substitute solvent to NMP (N‐methylpyrrolidone) in the catalytic arylation of 2‐phenylpyridine.
Co9S8/Co as a High‐Performance Anode for Sodium‐Ion Batteries with an Ether‐Based Electrolyte
Authors: Zhao Yingying , Pang Qiang , Wei Yingjin , Wei Luyao , Ju Yanming , Zou Bo , Gao Yu , Chen Gang
Published: September 2017

Co9S8 has been regarded as a desirable anode material for sodium‐ion batteries because of its high theoretical capacity. In this study, a Co9S8 anode material containing 5.5 wt % Co (Co9S8/Co) was prepared by a solid‐state reaction. The electrochemical properties of the material were studied in carbonate and ether‐based electrolytes (EBE). The results showed that the material had a longer cycle life and better rate capability in EBE. This excellent electrochemical performance was attributed to a low apparent activation energy and a low overpotential for Na deposition in EBE, which improved the electrode kinetic properties. Furthermore, EBE suppressed side reactions of the electrode and electrolyte, which avoided the formation of a solid electrolyte interphase film.
Predictive mapping of the biotic condition of conterminous U.S. rivers and streams
Authors: Hill Ryan A. , Fox Eric W. , Leibowitz Scott G. , Olsen Anthony R. , Thornbrugh Darren J. , Weber Marc H.
Published: September 2017

Understanding and mapping the spatial variation in stream biological condition could provide an important tool for conservation, assessment, and restoration of stream ecosystems. The USEPA's 2008–2009 National Rivers and Streams Assessment (NRSA) summarizes the percentage of stream lengths within the conterminous United States that are in good, fair, or poor biological condition based on a multimetric index of benthic invertebrate assemblages. However, condition is usually summarized at regional or national scales, and these assessments do not provide substantial insight into the spatial distribution of conditions at unsampled locations. We used random forests to model and predict the probable condition of several million kilometers of streams across the conterminous United States based on nearby and upstream landscape features, including human‐related alterations to watersheds. To do so, we linked NRSA sample sites to the USEPA's StreamCat Dataset; a database of several hundred landscape metrics for all 1:100,000‐scale streams and their associated watersheds within the conterminous United States. The StreamCat data provided geospatial indicators of nearby and upstream land use, land cover, climate, and other landscape features for modeling. Nationally, the model correctly predicted the biological condition class of 75% of NRSA sites. Although model evaluations suggested good discrimination among condition classes, we present maps as predicted probabilities of good condition, given upstream and nearby landscape settings. Inversely, the maps can be interpreted as the probability of a stream being in poor condition, given human‐related watershed alterations. These predictions are available for download from the USEPA's StreamCat website. Finally, we illustrate how these predictions could be used to prioritize streams for conservation or restoration.
Active dissemination of cellular antigens by DCs facilitates CD8+ T‐cell priming in lymph nodes
Authors: Gurevich Irina , Feferman Tali , Milo Idan , Tal Orna , Golani Ofra , Drexler Ingo , Shakhar Guy
Published: September 2017

Antigen (Ag) specific activation of naïve T cells by migrating dendritic cells (DCs) is a highly efficient process, although the chances for their colocalization in lymph nodes (LNs) appear low. Ag presentation may be delegated from Ag‐donor DCs to the abundant resident DCs, but the routes of Ag transfer and how it facilitates T‐cell activation remain unclear. We visualized CD8+ T cell‐DC interactions to study the sites, routes, and cells mediating Ag transfer in mice. In vitro, Ag transfer from isolated ovalbumin (OVA)+ bone marrow (BM) DCs triggered widespread arrest, Ca2+ flux, and CD69 upregulation in OT‐I T cells contacting recipient DCs. Intravital two‐photon imaging revealed that survival of Ag‐donor DCs in LNs was required for Ag dissemination among resident CD11c+ DCs. Upon interaction with recipient DCs, CD8+ T cells clustered, upregulated CD69, proliferated and differentiated into effectors. Few DCs sufficed for activation, and for efficient Ag dissemination lymphocyte function associated antigen 1 (LFA‐1) expression on recipient DCs was essential. Similar findings characterized DCs infected with a replication‐deficient OVA‐expressing Vaccinia virus known to downregulate MHC‐I. Overall, active Ag dissemination from live incoming DCs helped activate CD8+ T cells by increasing the number of effective presenting cells and salvaged T‐cell priming when Ag‐donor DCs could not present Ag.
One‐Pot Synthesis to Quinone‐Based Diaza[3.3]cyclophanes
Authors: Stahlhofen Jana Marie , Schollmeyer Dieter , Waldvogel Siegfried R.
Published: September 2017

A simple one‐pot synthesis to [3.3]cyclophanes that involves quinone moieties was found. The protocol tolerates a variety of amines that include aliphatic and aromatic structures with different functional groups, such as hydroxy groups, amides, and terminal double and triple bonds. The straightforward synthesis can be performed by a twofold N‐alkylation reaction with 2,5‐bis(bromomethyl)‐3,6‐dimethyl‐1,4‐benzoquinone (1). Neither anhydrous nor inert conditions are required. Various amines can be employed without any activating groups, several functionalities at end groups are tolerated, and the cyclophanes generated can be easily modified or embedded into larger molecular architectures. The redox‐active nature of these cyclophanes allows their use in electron‐transfer processes.
A Bayesian semiparametric GLMM for historical and newly collected presence‐only data: An application to species richness of Ross Sea Mollusca
Authors: Carota C. , Nava C. R. , Ghiglione C. , Schiaparelli S.
Published: September 2017

Historical data sets from vast and relatively inaccessible areas are sources of potentially unique information still valuable for biodiversity studies today. In many research fields, ranging from climate change to projection of species loss, great efforts have been made to integrate historical data sets with recent data to create databases that are as complete as possible. Unlocking the information contained in presence‐only data, largely prevalent in such databases, presents a challenge for statistical modeling because of insidious observational errors due to the opportunistic nature of the data‐gathering process. In this article, we propose an appropriate statistical method for the joint analysis of historical and newly collected presence‐only data, that is, a Bayesian semiparametric generalized linear mixed model with Dirichlet process random effects. The potential of the method is illustrated by considering the Ross Sea section of the SOMBASE, an international compilation of Southern Ocean Mollusc distributional records, from 1899 to 2004 and beyond. Despite the presence of sampling bias and nondetection errors, the proposed model draws latent information from the data, such that the resulting estimates of the parameters of interest not only are coherent with those obtained in indirectly related studies based on well‐structured data but also suggest interesting ideas for further research.
Stability of supraglacial debris
Authors: Moore Peter L.
Published: September 2017

Rock debris on the surface of ablating glaciers is not static, and is often transported across the ice surface as relief evolves during melt. This supraglacial debris transport has a strong influence on the spatial distribution of melt, and is implicated in the formation of hummocky glacial topography in deglaciated terrain. Furthermore, as ice‐dammed lakes and ice‐cored slopes become increasingly common in deglaciating watersheds, there is rising concern about hazards to humans and infrastructure posed by mass‐wasting of ice‐cored debris. The existing quantitative framework for describing these debris transport processes is limited, making it difficult to account for transport in mass balance, hazard assessment, and landscape development models. This paper develops a theoretical framework for assessing slope stability and gravitational mass transport in a debris‐covered ice setting. Excess water pressure at the interface between ablating ice and lowering debris is computed by combining Darcy's law with a meltwater balance. A limit‐equilibrium slope stability analysis is then applied to hypothetical debris layers with end‐member moisture conditions derived from a downslope meltwater balance that includes production and seepage. The resulting model system constrains maximum stable slope angles and lengths that vary with debris texture, thickness, and the rate of meltwater production. Model predictions are compared with field observations and with digital elevation model (DEM)‐derived terrain metrics from two modern debris‐covered glaciers on Mount Rainier, USA. Copyright © 2017 John Wiley & Sons, Ltd.
Jellyfish and other gelata as food for four penguin species – insights from predator‐borne videos
Authors: Thiebot Jean‐Baptiste , Arnould John PY , Gómez‐Laich Agustina , Ito Kentaro , Kato Akiko , Mattern Thomas , Mitamura Hiromichi , Noda Takuji , Poupart Timothée , Quintana Flavio , Raclot Thierry , Ropert‐Coudert Yan , Sala Juan E , Seddon Philip J , Sutton Grace J , Yoda Ken , Takahashi Akinori
Published: September 2017

Jellyfish and other pelagic gelatinous organisms (“gelata”) are increasingly perceived as an important component of marine food webs but remain poorly understood. Their importance as prey in the oceans is extremely difficult to quantify due in part to methodological challenges in verifying predation on gelatinous structures. Miniaturized animal‐borne video data loggers now enable feeding events to be monitored from a predator's perspective. We gathered a substantial video dataset (over 350 hours of exploitable footage) from 106 individuals spanning four species of non‐gelatinous‐specialist predators (penguins), across regions of the southern oceans (areas south of 30°S). We documented nearly 200 cases of targeted attacks on carnivorous gelata by all four species, at all seven studied localities. Our findings emphasize that gelatinous organisms actually represent a widespread but currently under‐represented trophic link across the southern oceans, even for endothermic predators, which have high energetic demands. The use of modern technological tools, such as animal‐borne video data loggers, will help to correctly identify the ecological niche of gelata.
Flexibility as firm value driver: Evidence from offshore outsourcing
Authors: Choi Jongmoo J. , Ju Ming , Kotabe Masaaki , Trigeorgis Lenos , Zhang Xiaotian T.
Published: September 2017

Research Summary

This article tests real options theory predictions that uncertainty and flexibility are key value drivers for offshore outsourcing moderated by switching costs. Examining firm‐specific and market data for outsourcing cases by U.S. firms, we find that the impact of market and environmental uncertainty and flexibility on outsourcing value is net positive and that it is greater for offshore than for domestic outsourcing. Outsourcing benefits are related to flexibility arising from growth options and moderated by switching costs underlying outsourcing activities, including loss of innovative capability and economic, institutional, and cross‐country cultural differences.

Managerial Summary

In the popular business literature, the “footloose” nature of outsourcing strategy characterized by an outsourcing firm's flexibility, as well as the ability in finding appropriate suppliers on a global basis, has often been touted as an important means of dealing with market uncertainty. However, the academic literature has not offered direct empirical support for the inherent value of such outsourcing strategies. Our study shows that firms tend to perform better financially when they have such outsourcing flexibility under uncertain market and environmental conditions, although this relationship may be somewhat weakened by potential loss of innovative capability and cultural and other differences in dealing with foreign suppliers.
Middle cerebral artery Doppler reference centile charts for the prediction of fetal anemia in a population from India
Authors: Kumar Manisha , Umrawal Tarul , Singh Anuradha
Published: September 2017

Objective

To construct reference charts for the fetal middle cerebral artery (MCA) peak systolic velocity (PSV,) and the corresponding cord blood hemoglobin values at 24–40 weeks of pregnancy for the identification of fetal anemia.

Methods

In a cross‐sectional study, 300 women with a pregnancy duration of 24–40 weeks planned for delivery within 72 hours underwent a Doppler study of the MCA and cord blood hemoglobin estimation at delivery. Regression analysis was used to construct reference charts. The validity of the charts was assessed in 40 fetuses from Rhesus‐isoimmunized pregnancies.

Results

The MCA PSV and hemoglobin values increased with advancing gestational age. Multiples of the median (MOM) were calculated and reference charts were constructed for mild anemia (MCA PSV 1.29 MOM; hemoglobin 0.8 MOM), moderate anemia (MCA PSV 1.50 MOM; hemoglobin 0.6 MOM), and severe anemia (MCA PSV 1.55 MOM; hemoglobin 0.5 MOM). In the validation sample, the hemoglobin value estimated on the basis of the MCA PSV corresponded with the actual hemoglobin range in 90% of the fetuses. The sensitivity was 92% and the specificity was 95%.

Conclusion

The constructed charts are suitable for the evaluation of fetal anemia in the regional population.
Simulated relationship between air temperature and precipitation over Europe: sensitivity to the choice of RCM and GCM
Authors: Crhová Lenka , Holtanová Eva
Published: September 2017

This paper presents an evaluation of the relationship between near‐surface air temperature (T) and precipitation (P) over Europe simulated by regional climate models (RCMs) from the EURO‐CORDEX project. Simulations of two RCMs (RCA4 and CCLM4‐8‐17) driven by four different global climate models (GCMs) in the period 1971–2000 were analysed. Two different coefficients, the Pearson correlation coefficient based on monthly anomalies and the T‐P index (TPI) based on daily values, were used for this evaluation. First, the comparison of T‐P correlation and TPI patterns calculated from E‐OBS data was made. Afterwards, simulated T‐P relationship patterns were briefly evaluated. We especially focused on evaluating the RCM and GCM influence on the simulated T‐P relationship pattern. Our results indicate that RCM simulations captured the basic seasonal dependence of the T‐P relationship over Europe represented by both T‐P correlation and TPI patterns. The simulated T‐P relationship pattern is more strongly influenced by an RCM than a driving GCM in contrast to temperature means in winter and precipitation and temperatures changes, which are more strongly influenced by driving GCM as shown in previous studies. The simulations of the CCLM4‐8‐17 RCM demonstrated noticeably better agreement with observed T‐P relationship fields than the RCA4 RCM simulations. The T‐P relationship simulated by RCA4 tends to shift to positive values in comparison to E‐OBS values. These findings were found for both TPI and T‐P correlation.
Analysis of moisture, oil, and fatty acid composition of olives by near‐infrared spectroscopy: development and validation calibration models
Authors: Saha Uttam , Jackson Daniel
Published: September 2017

BACKGROUND

Olive is a new, expanding crop in Georgia. Its oil content steadily increases with maturity, but eventually plateaus at the maximum when the olives should be promptly harvested, avoiding overripening and quality degradation. This requires frequent testing. However, olive quality analysis by wet chemistry is laborious, slow and costly, whereas near‐infrared reflectance spectroscopy (NIRS), being precise, accurate, rapid and cheap, could be suitable. We developed and validated NIRS calibration models for moisture, fresh‐matter‐oil (oil‐FMO), dry‐matter‐oil (oil‐DMO) and major fatty acid composition analyses.

RESULTS

Of the12 models developed, seven constituents – moisture, oil‐FMO, oil‐DMO, and palmitic, palmitoleic, oleic and linoleic acids (representing 88–97% of the total fatty acids) had low standard errors and high coefficients of determination (R2 = 0.81–0.98; 1 − VR = 0.74–0.86) for both calibration and cross‐validation. For these seven constituents, predictions of an independent validation set yielded excellent agreement between the NIRS predicted values and the reference values with low standard error of prediction (SEP), low bias, high coefficient of determination (r2 = 0.80–0.93) and high ratios of performance to deviation (RPD = SD/SEP; 2.21–3.85).

CONCLUSION

Precise, accurate and rapid analysis of fresh olives for moisture, oil and major fatty acid composition can be done at a low cost using NIRS, meeting the analytical needs of the industry. © 2017 Society of Chemical Industry
Enhanced recovery after surgery: Pain management
Authors: Nimmo Susan M. , Foo Irwin T.H. , Paterson Hugh M.
Published: September 2017

Effective pain management is fundamental to enhanced recovery after surgery. Selection of strategies should be tailored to patient and operation. As well as improving the quality of recovery, effective analgesia reduces the host stress response, facilitates mobilization and allows resumption of oral intake. Multi‐modal regimens combining paracetamol, non‐steroidal anti‐inflammatory agents where indicated, a potent opioid and a local anaesthetic technique achieve effective analgesia while limiting the dose and thereby side effects of any one agent.
Effect of welding wire and groove angle on mechanical properties of high strength steel welded joints
Authors: Evci C. , Işık H. , Macar M.
Published: September 2017

Mechanical properties of high strength steel welded joints strictly depend on the welding process, the filler material composition and the welding geometry. This study investigates the effects of using cored and solid welding wires and implementing various groove angles on the mechanical performance of weld joints which were fabricated employing the gas metal arc welding process. It was found that weld joints of low alloy, high strength steels using low alloy steel cored welding wires exhibited higher tensile strength than that of low alloy steel solid wire and chromium‐nickel steel bare welding wire when the method of gas metal arc welding is employed. The effect of groove angle on the strength and toughness of V‐groove and double V‐groove butt‐joints was investigated. V‐groove joints, with higher tensile strength than double V‐groove joints in the whole range of groove angles, were superior in toughness for small groove angles, but impact toughness values of both joints were comparable for large angles. The effect of heat input and cooling rate on the weld microstructure and weld strength was also investigated by performing thermal analysis employing the commercial software ANSYS. It was concluded that cooling rate and solidification growth rate determined the microstructure of the weld zone which had great consequences in regard to mechanical properties.