bluuebunny/crossref_metadata_2025 huggingface dataset:
Porous Hydrogel Encapsulated Photonic Barcodes for Multiplex MicroRNA Quantification
Authors: Xu Yueshuang , Wang Huan , Luan Chengxin , Fu Fanfan , Chen Baoan , Liu Hong , Zhao Yuanjin
Published: November 2017

The development of a highly sensitive platform for multiplex circulating microRNAs (miRNAs) detection is important for clinical diagnosis. Here, a new type of porous hydrogel encapsulated photonic crystal (PhC) barcodes is presented with integrated rolling circle amplification (RCA) strategy for multiplex miRNA quantification. As the surrounding porous hydrogel shells of the PhC barcodes are interconnected inverse opal structure with hydrophilic scaffolds, they can provide homogeneous water surrounding for the miRNA targets reaction and RCA. The encapsulated PhC cores of the barcodes can offer stable diffraction peaks for encoding different miRNAs and their RCAs during the detection. By integrating the advantages of PhC barcodes and RCA, it is demonstrated that the technology shows acceptable accuracy and detection reproducibility for the rapid quantification of low‐abundance miRNAs, with the limits of detection of 20 fM. Thus, the proposed porous hydrogel encapsulated PhC barcodes provide a new platform for the multiplex quantification of low‐abundance targets for practical applications.
Ultrafine Nickel‐Nanoparticle‐Enabled SiO2 Hierarchical Hollow Spheres for High‐Performance Lithium Storage
Authors: Tang Chunjuan , Liu Yuning , Xu Chang , Zhu Jiexin , Wei Xiujuan , Zhou Liang , He Liang , Yang Wei , Mai Liqiang
Published: November 2017

The high theoretical capacity and natural abundance of SiO2 make it a promising high‐capacity anode material for lithium‐ion batteries. However, its widespread application is significantly hampered by the intrinsic poor electronic conductivity and drastic volume variation. Herein, a unique hollow structured Ni/SiO2 nanocomposite constructed by ultrafine Ni nanoparticle (≈3 nm) functionalized SiO2 nanosheets is designed. The Ni nanoparticles boost not only the electronic conductivity but also the electrochemical activity of SiO2 effectively. Meanwhile, the hollow cavity provides sufficient free space to accommodate the volume change of SiO2 during repeated lithiation/delithiation; the nanosheet building blocks reduce the diffusion lengths of lithium ions. Due to the synergistic effect between Ni and SiO2, the Ni/SiO2 composite delivers a high reversible capacity of 676 mA h g−1 at 0.1 A g−1. At a high current density of 10 A g−1, a capacity of 337 mA h g−1 can be retained after 1000 cycles.
Light‐Responsive Ion‐Redistribution‐Induced Resistive Switching in Hybrid Perovskite Schottky Junctions
Authors: Guan Xinwei , Hu Weijin , Haque Md Azimul , Wei Nini , Liu Zhixiong , Chen Aitian , Wu Tom
Published: November 2017

Hybrid Perovskites have emerged as a class of highly versatile functional materials with applications in solar cells, photodetectors, transistors, and lasers. Recently, there have also been reports on perovskite‐based resistive switching (RS) memories, but there remain open questions regarding device stability and switching mechanism. Here, an RS memory based on a high‐quality capacitor structure made of an MAPbBr3 (CH3NH3PbBr3) perovskite layer sandwiched between Au and indium tin oxide (ITO) electrodes is reported. Such perovskite devices exhibit reliable RS with an ON/OFF ratio greater than 103, endurance over 103 cycles, and a retention time of 104 s. The analysis suggests that the RS operation hinges on the migration of charged ions, most likely MA vacancies, which reversibly modifies the perovskite bulk transport and the Schottky barrier at the MAPbBr3/ITO interface. Such perovskite memory devices can also be fabricated on flexible polyethylene terephthalate substrates with high bendability and reliability. Furthermore, it is found that reference devices made of another hybrid perovskite MAPbI3 consistently exhibit filament‐type switching behavior. This work elucidates the important role of processing‐dependent defects in the charge transport of hybrid perovskites and provides insights on the ion‐redistribution‐based RS in perovskite memory devices.
Gold Nanoparticles Sliding on Recyclable Nanohoodoos—Engineered for Surface‐Enhanced Raman Spectroscopy
Authors: Wu Kaiyu , Li Tao , Schmidt Michael Stenbæk , Rindzevicius Tomas , Boisen Anja , Ndoni Sokol
Published: November 2017

Robust, macroscopically uniform, and highly sensitive substrates for surface‐enhanced Raman spectroscopy (SERS) are fabricated using wafer‐scale block copolymer lithography. The substrate consists of gold nanoparticles that can slide and aggregate on dense and recyclable alumina/silicon nanohoodoos. Hot‐spot engineering is conducted to maximize the SERS performance of the substrate. The substrate demonstrates remarkably large surface‐averaged SERS enhancements, greater than 107 (>108 in hot spots), with unrivalled macroscopic signal uniformity as characterized by a coefficient of variation of only 6% across 4 cm. After SERS analyses, the nanohoodoos can be recycled by complete removal of gold via a one‐step, simple, and robust wet etching process without compromising performance. After eight times of recycling, the substrate still exhibits identical SERS performance in comparison to a new substrate. The macroscopic uniformity combined with recyclability at conserved high performance is expected to contribute significantly on the overall competitivity of the substrates. These findings show that the gold nanoparticles sliding on recyclable nanohoodoo substrate is a very strong candidate for obtaining cost‐effective, high‐quality, and reliable SERS spectra, facilitating a wide and simple use of SERS for both laboratorial and commercial applications.
Tubular TiO2 Nanostructures: Toward Safer Microsupercapacitors
Authors: Salari Maryam , Aboutalebi Seyed Hamed , Ekladious Iriny , Jalili Rouhollah , Konstantinov Konstantin , Liu Hua Kun , Grinstaff Mark W.
Published: November 2017

Self‐organized tubular nanostructures, synthesized through straightforward and efficient techniques, are anisotropic materials, catalyzing many research breakthroughs, and, are of interest as electrode materials for electrochemical microdevices. The fabrication and characterization of microsupercapacitors composed of self‐assembled titanium dioxide (TiO2) nanotubes, as a combined current collector and electrode, are described. Moreover, conventional toxic acidic or alkaline electrolytes are not required, and the device operates with phosphate buffered saline as the electrolyte. Higher volumetric capacitance (84 F cm−3) and energy density (1.15 mWh cm−3) values are obtained with the anodized TiO2 microsupercapacitor devices compared with the conventional ones that employ carbon‐based electrodes and organic electrolytes. Achieving high capacitance through the use of a safe neutral aqueous electrolyte, combined with the biocompatibility of TiO2 and Ti films, opens up new avenues for the utilization of this system and its design for energy delivery or harvesting in biological and medical applications.
Guidelines in CHARGE syndrome and the missing link: Cranial imaging
Authors: de Geus Christa M. , Free Rolien H. , Verbist Berit M. , Sival Deborah A. , Blake Kim D. , Meiners Linda C. , van Ravenswaaij‐Arts Conny M. A.
Published: November 2017

“CHARGE syndrome” is a complex syndrome with high and extremely variable comorbidity. As a result, clinicians may struggle to provide accurate and comprehensive care, and this has led to the publication of several clinical surveillance guidelines and recommendations for CHARGE syndrome, based on both single case observations and cohort studies. Here we perform a structured literature review to examine all the existing advice. Our findings provide additional support for the validity of the recently published Trider checklist. We also identified a gap in literature when reviewing all guidelines and recommendations, and we propose a guideline for neuroradiological evaluation of patients with CHARGE syndrome. This is of importance, as patients with CHARGE are at risk for peri‐anesthetic complications, making recurrent imaging procedures under anesthesia a particular risk in clinical practice. However, comprehensive cranial imaging is also of tremendous value for timely diagnosis, proper treatment of symptoms and for further research into CHARGE syndrome. We hope the guideline for neuroradiological evaluation will help clinicians provide efficient and comprehensive care for individuals with CHARGE syndrome.
The relationship between social play and developmental milestones in wild chimpanzees (Pan troglodytes schweinfurthii)
Authors: Heintz Matthew R. , Murray Carson M. , Markham A. Catherine , Pusey Anne E. , Lonsdorf Elizabeth V.
Published: November 2017

Social play is common among many group‐living animals, but the benefits are not well understood. Proposed benefits include increased muscle coordination as the result of increased locomotor versatility and development, and strengthened social bonds through interactions with like‐aged individuals. In this study, we used 33 years of long‐term behavioral data on infant chimpanzees in Gombe National Park, Tanzania, to examine these potential benefits of social play, specifically how the percentage of time engaged in social play relates to motor and social developmental milestones. We predicted that infants who engaged in more social play would achieve motor and social milestones at younger ages. We found that individuals that spent more time engaging in social play achieved the motor milestones of riding dorsally and traveling independently at earlier ages. Additionally, we found that the amount of play was correlated with earlier ages for reaching the social milestones of spatial independence from mother, first grooming of non‐maternal kin, and first observed mating attempt. This is the first study in great apes to demonstrate a relationship between play behavior and developmental milestones, supporting the hypotheses that play provides motor, and social benefits.
Quaternary β2,2‐Amino Acids: Catalytic Asymmetric Synthesis and Incorporation into Peptides by Fmoc‐Based Solid‐Phase Peptide Synthesis
Authors: Yu Jin‐Sheng , Noda Hidetoshi , Shibasaki Masakatsu
Published: November 2017

β‐Amino acid incorporation has emerged as a promising approach to enhance the stability of parent peptides and to improve their biological activity. Owing to the lack of reliable access to β2,2‐amino acids in a setting suitable for peptide synthesis, most contemporary research efforts focus on the use of β3‐ and certain β2,3‐amino acids. Herein, we report the catalytic asymmetric synthesis of β2,2‐amino acids and their incorporation into peptides by Fmoc‐based solid‐phase peptide synthesis (Fmoc‐SPPS). A quaternary carbon center was constructed by the palladium‐catalyzed decarboxylative allylation of 4‐substituted isoxazolidin‐5‐ones. The N−O bond in the products not only acts as a traceless protecting group for β‐amino acids but also undergoes amide formation with α‐ketoacids derived from Fmoc‐protected α‐amino acids, thus providing expeditious access to α‐β2,2‐dipeptides ready for Fmoc‐SPPS.
Development of sericin/alginate particles by ionic gelation technique for the controlled release of diclofenac sodium
Authors: Vidart Jacyara Moreira Martins , Silva Thiago Lopes da , Rosa Paulo César Pires , Vieira Melissa Gurgel Adeodato , Silva Meuris Gurgel Carlos da
Published: November 2017

Sericin and alginate particles, prepared by ionic gelation technique, demonstrated to be a promising matrix to controlled release of diclofenac sodium. Ten particle compositions of sericin, alginate, and diclofenac were evaluated. The drug incorporation was confirmed by scanning electron microscopy, Fourier Transform Infrared Spectroscopy, and X‐ray diffraction analysis. In vitro dissolution profile was performed to obtain the drug release profile in gastric and enteric medium. The drug release profile indicated that sericin delays the release and alginate contributes to the gastro‐resistance of formulations. The blend with composition of 2.5% of sericin, 2.8% of alginate with 2.0% w/v of diclofenac demonstrated to be feasible for drug delivery due the entrapment efficiency of 81.06% and release delay of 360 min, the highest time of all investigated compositions. The mathematical modeling showed that the drug release mechanism is associated to the process of swelling, matrix erosion, and a combination of diffusion and chain relaxation mechanisms. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45919.
COOHMWCNTs‐induced BiFeO3‐poly(vinylidene fluoride) (PVDF) composites with enhanced dielectric and ferroelectric properties
Authors: Moharana Srikanta , Mahaling Ram Naresh
Published: November 2017

In this work, flexible three phase composite films were prepared with surface functionalized multi‐walled carbon nanotubes (f‐MWCNTs) and bismuth ferrite (BiFeO3;BFO) particles embedded into the poly(vinylidene fluoride) (PVDF) matrix via solution casting technique. The properties and the microstructure of prepared composites were investigated using an impedance analyzer and field emission scanning electron microscope. The micro‐structural study showed that the f‐MWCNTs and BFO particles were dispersed homogeneously within the PVDF matrix, nicely seated on the floor of the f‐MWCNTs separately. The dielectric measurement result shows that the resultant composites with excellent dielectric constant (≈96) and relatively lower dielectric loss (<0.23 at 100 Hz). Furthermore, the percolation theory is explored to explain the dielectric properties of the resultant composites. It says that the percolation threshold of fMWCNTs = 0.9 wt % and the enhancement of the dielectric constant of the composite was also discussed. In addition, the remnant polarization of the un‐poled PVDF‐BFO‐f‐MWCNTs composites (2Pr ∼1.34 µC/cm2 for 1.1 wt % of f‐MWCNTs) is also improved. These three phase composites provide a new insight to fabricate flexible and enhanced dielectric properties as a promising application in modern electrical and electronic devices. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46002.
Octadecyl‐silica—PVDF membrane of superior MD desalination performance
Authors: Mistry Rupal J. , Saxena Mayank , Ray Paramita , Singh Puyam S.
Published: November 2017

Despite its widespread industrial and residential uses for production of potable water, the reverse osmosis (RO) desalination process has some drawbacks by discharging harmful concentrated saline water as reject stream. A hydrophobic porous membrane can treat such environmentally unfriendly RO reject stream via Membrane Distillation (MD) process. Here, we describe preparation of superior polyvinylidenefluoride (PVDF) membrane modified with superhydrophobic silica nanoparticles for desalination application. Superhydrophobicity (contact angle of 151°) of silica nanoparticles of 7 nm sizes was achieved by reaction of the silica particles with octadecyltrichlorosilane in toluene to form SiOSi links with C18 alkyl chain. A homogeneous polymer dope mixture containing a desired amount of modified silica colloids suspended in toluene was used for the membrane preparation. The PVDF membrane with optimal silica content exhibited excellent flux with >99% salt rejection efficiency when used for MD at room temperature from the saline water feed of 3.5 wt % NaCl. The prepared hydrophobic PVDF membrane has the potential for MD application in treating the RO reject stream and other aqueous industrial effluents. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46043.
Analysis of euphotic depth in snow with SNICAR transfer scheme
Authors: Zhong Efang , Li Qian , Sun Shufen , Chen Shangfeng , Chen Wen
Published: November 2017

Solar radiation in the visible spectrum can penetrate through snowpack to a considerable depth, which is named as the euphotic depth in snow. If the snow depth is no greater than the euphotic depth, the surface albedo is greatly affected by the underlying surface. This study defines the euphotic depth as the depth where the residual solar radiation in snow began to be less than 1.0 W m−2 and provides a convenient approach to estimate it. A two‐stream, multilayer radiation penetration model (SNow, ICe, and Aerosol Radiation) was applied to predict the vertical profiles of solar radiation based on regular measurements of snow pits and downward solar radiation at Col de Porte (CDP), France from 1993 to 2011. The euphotic depth in snow at CDP exhibits clear seasonal variations, with median values in winter months of 6.8, 8.8, and 10.5 cm, and those in spring remaining nearly on the same level (24.4 and 24.2 cm). The maximum euphotic depth at CDP reached as deep as 78 cm. Further analyses demonstrated that the euphotic depth in snow is related to not only the external initial solar irradiance but also the interior snow extinction coefficient. Stronger illumination and smaller snow extinction coefficients may correspond to greater euphotic depths in snowpack.
Growth rates of pulmonary metastases after liver transplantation for unresectable colorectal liver metastases
Authors: Grut H , Solberg S , Seierstad T , Revheim M E , Egge T S , Larsen S G , Line P D , Dueland S
Published: November 2017

Background

The previously reported SECA study demonstrated a dramatic 5-year survival improvement in patients with unresectable colorectal liver metastases (CLM) treated with liver transplantation (LT) compared with chemotherapy. The objective of this study was to assess whether immunosuppressive therapy accelerates the growth of pulmonary metastases in patients transplanted for unresectable CLM.

Methods

Chest CT scans from 11 patients in the SECA study resected for 18 pulmonary metastases were reviewed retrospectively. Tumour diameter, volume and CT characteristics were registered and tumour volume doubling time was calculated. Findings in the SECA group were compared with those of a control group consisting of 12 patients with non-transplanted rectal cancer resected for 26 pulmonary metastases. Disease-free survival (DFS) and overall survival (OS) after first pulmonary resection were determined.

Results

Median doubling time based on tumour diameter and volume in the SECA and control groups were 125 and 130 days (P = 0·658) and 110 and 129 days (P = 0·632) respectively. The metastases in both groups were distributed to all lung lobes and were mostly peripheral. Median DFS after LT in the SECA group and after primary pelvic surgery in the control group was 17 (range 6–42) and 18 (2–57) months respectively (P = 0·532). In the SECA group, estimated 5-year DFS and OS rates after first pulmonary resection were 39 and 51 per cent respectively.

Conclusion

Patients treated by LT for unresectable CLM have a good prognosis following resection of pulmonary metastases. Doubling time did not appear to be worse with the immunosuppression used after LT.
Quality of life in a randomized trial of early closure of temporary ileostomy after rectal resection for cancer (EASY trial)
Authors: Park J , Danielsen A K , Angenete E , Bock D , Marinez A C , Haglind E , Jansen J E , Skullman S , Wedin A , Rosenberg J
Published: November 2017

Background

A temporary ileostomy may reduce symptoms from anastomotic leakage after rectal cancer resection. Earlier results of the EASY trial showed that early closure of the temporary ileostomy was associated with significantly fewer postoperative complications. The aim of the present study was to compare health-related quality of life (HRQOL) following early versus late closure of a temporary ileostomy.

Methods

Early closure of a temporary ileostomy (at 8–13 days) was compared with late closure (at more than 12 weeks) in a multicentre RCT (EASY) that included patients who underwent rectal resection for cancer. Inclusion of participants was made after index surgery. Exclusion criteria were signs of anastomotic leakage, diabetes mellitus, steroid treatment, and signs of postoperative complications at clinical evaluation 1–4 days after rectal resection. HRQOL was evaluated at 3, 6 and 12 months after resection using the European Organisation for Research and Treatment of Cancer (EORTC) questionnaires QLQ-C30 and QLQ-CR29 and Short Form 36 (SF-36®).

Results

There were 112 patients available for analysis. Response rates of the questionnaires were 82–95 per cent, except for EORTC QLQ-C30 at 12 months, to which only 54–55 per cent of the patients responded owing to an error in questionnaire distribution. There were no clinically significant differences in any questionnaire scores between the groups at 3, 6 or 12 months.

Conclusion

Although the randomized study found that early closure of the temporary ileostomy was associated with significantly fewer complications, this clinical advantage had no effect on the patients' HRQOL. Registration number: NCT01287637 (https://www.clinicaltrials.gov).
Schedule dependent synergy of gemcitabine and doxorubicin: Improvement of in vitro efficacy and lack of in vitro‐in vivo correlation
Authors: Vogus Douglas R. , Pusuluri Anusha , Chen Renwei , Mitragotri Samir
Published: November 2017

Combination chemotherapy is commonly used to treat late stage cancer; however, treatment is often limited by systemic toxicity. Optimizing drug ratio and schedule can improve drug combination activity and reduce dose to lower toxicity. Here, we identify gemcitabine (GEM) and doxorubicin (DOX) as a synergistic drug pair in vitro for the triple negative breast cancer cell line MDA‐MB‐231. Drug synergy and caspase activity were increased the most by exposing cells to GEM prior to DOX in vitro. While the combination was more effective than the single drugs at inhibiting MDA‐MB‐231 growth in vivo, the clear schedule dependence observed in vitro was not observed in vivo. Differences in drug exposure and cellular behavior in vivo compared to in vitro are likely responsible. This study emphasizes the importance in understanding how schedule impacts drug synergy and the need to develop more advanced strategies to translate synergy to the clinic.
Selective Production of Oxygenates from Carbon Dioxide Hydrogenation over a Mesoporous‐Silica‐Supported Copper‐Gallium Nanocomposite Catalyst
Authors: Hengne Amol M. , Bhatte Kushal D. , Ould‐Chikh Samy , Saih Youssef , Basset Jean Marie , Huang Kuo‐Wei
Published: November 2017

The hydrogenation of CO2 to oxygenates (methanol and dimethyl ether; DME) was investigated over bifunctional supported Cu catalysts promoted with Ga. The supported Cu‐Ga nanocomposite catalysts were characterized by using XRD, TEM with energy dispersive X‐ray spectroscopy, X‐ray photoelectron spectroscopy, and H2 temperature‐programmed reduction. In comparison with Cu‐SBA‐15‐based catalysts, the Ga‐promoted catalyst prepared by the urea deposition method (Cu‐Ga/SBA‐15‐UDP) was more active and selective for CO2 hydrogenation to oxygenates. The use of Ga as the promoter led to increased acidic sites, which was confirmed by using NH3 temperature‐programmed deposition and IR spectroscopy with pyridine and 2,6‐lutidine as probe molecules. The favorable effect of Ga on the CO2 conversion and selectivity to oxygenates may come from the strong interaction of Ga with silica, which is responsible for the enhanced metal surface area, the formation of the nanocomposite, and the metal dispersion. Notably, the incorporation of Ga into Cu/SiO2 led to a several‐fold higher rate for methanol formation (13.12 μmol gCu−1 s−1) with a reasonable rate for DME formation (2.15 μmol gCu−1 s−1) compared to Cu/SiO2 catalysts.
Dual Brønsted‐acid Organocatalysis: Cooperative Asymmetric Catalysis with Combined Phosphoric and Carboxylic Acids
Authors: Mitra Raja , Niemeyer Jochen
Published: November 2017

How can an assisting Brønsted‐acid be beneficial in asymmetric Brønsted‐acid catalysis? In this Minireview, we discuss selected examples of chiral organocatalysts that feature two acidic groups working cooperatively by virtue of intra‐ or intermolecular hydrogen‐bonding. In these systems, the assisting Brønsted‐acid can play different roles, ranging from simple hydrogen‐bond donation, to substrate‐binding or even as a nucleophilic reaction partner. By analysis of combined experimental, structural and theoretical data, we aim at developing a better understanding of the reaction mechanisms, which are largely influenced by the underlying intramolecular‐ and intermolecular catalyst‐substrate interactions. This may aid in the future development of more selective dual Brønsted‐acid organocatalysts for specific asymmetric transformations.
Advances in Nanocatalyst Design for Biofuel Production
Authors: Zuliani Alessio , Ivars Francisco , Luque Rafael
Published: November 2017

The exploitation of nanocatalysts, at the boundary between homogeneous and heterogeneous catalysis, offers new efficient ways to produce renewable biofuels in environmentally friendly conditions. Specifically, biodiesel and high density fuels have been chosen as major topics of research for the design of catalytic nanomaterials. As solid‐state catalysts, they are recyclable, and their nanometric particle size enables high activities that approach those of homogeneous catalysts. In addition, they offer novel and unique catalytic behaviors not accessible to solids above the nanometer range. Furthermore, the use of magnetically active materials has led to the development of nanocatalysts easily recoverable through the application of magnetic fields. In this Minireview, the latest achievements in the production of advanced biofuels using stable, highly active, cheap and reusable nanocatalysts are described.
Wiring Gold Nanoparticles and Redox Enzymes: A Self‐Sufficient Nanocatalyst for the Direct Oxidation of Carbohydrates with Molecular Oxygen
Authors: Ratautas Dalius , Ramonas Eimantas , Marcinkevičienė Liucija , Meškys Rolandas , Kulys Juozas
Published: November 2017

The development of artificial nanocatalysts, especially those incorporating the highly active biocatalysts (enzymes) present in nature, is a rapidly developing field in nanocatalysis and nanomaterials science. Dehydrogenases are exceptionally attractive, as they catalyze the oxidation of various cheap/common substrates to more expensive and desired products. However, their use in sustainable catalysis and/or their incorporation in advanced nanomaterials with catalytic functions are limited owing to one immense problem that can be formulated as a question: how can the electrons received from the oxidized substrate be removed? Here, a solution to this problem is demonstrated: we designed a unique nanomaterial composed of two redox enzymes (nonspecific glucose dehydrogenase and oxygen‐reducing laccase) and gold nanoparticles. Both enzymes were wired through the gold nanoparticles (10 nm) and direct electrochemical “communication” was achieved, allowing electron transfer from the redox center of glucose dehydrogenase to a copper center of laccase. As a result, self‐sufficient nanocatalysts were synthesized and shown to oxidize various carbohydrates directly with molecular oxygen.
Electrochemical Formation of Gold Nanoparticles on Polycrystalline Gold Electrodes during Prolonged Potential Cycling
Authors: Ahrens Paula , Zander Manfred , Hasse Ulrich , Wulff Harm , Jeyabharathi Chinnaya , Kruth Angela , Scholz Fritz
Published: November 2017

The voltammetric behavior of polycrystalline gold electrodes in 0.1 M sulfuric acid and the influence of prolonged repetitions of oxidation and reduction cycles at different scan rates on the surface morphology was studied. Slow (0.1 V s−1) as well as fast (1.0 V s−1) scan rates lead to an intense roughening of the electrode surface and the formation of a variety of different crystalline particles on it. These crystallites, their formation, and the influence of surface pretreatment were investigated with electrochemical methods, X‐ray diffraction measurements, and scanning electron microscopy. Additionally, an interpretation of the changing electrochemical signals of polycrystalline gold during prolonged potential cycling is given.
Eco‐friendly synthesis from industrial wastewater of Fe and Cu nanoparticles over NaX zeolite and activity in 4‐nitrophenol reduction
Authors: Elfiad Amal , Boffito Daria Camilla , Khemassia Sihem , Galli Federico , Chegrouche Salah , Meddour‐Boukhobza Laaldja
Published: November 2017

We deposited Fe and Cu over zeolite NaX (Fe/NaX and Cu/NaX) by adsorption from effluent industrial wastewater. We synthesized the zeolite NaX by the hydrothermal method. 5 g of NaX completely adsorbed 350 and 380 mg of Fe and Cu from the industrial wastewater, respectively, in 6 h. The distribution of Fe and Cu over the NaX was uniform and amounted at 14 and 18 mass%, respectively. Fe and Cu modify the morphology of the NaX zeolite: the particle size increased from 9 μm to 10 μm for the former and decreased to 3 μm for the latter. Fe/NaX and Cu/NaX are less crystalline than NaX. BET analysis showed that the specific surface area decreased by 30 % and 50 % compared to NaX for Fe/NaX and Cu/NaX, but the ratio between meso‐ and micropores increased by 7 and 13 times, respectively. Fe/NaX and Cu/NaX synthesized by adsorption from industrial wastewater reduced +99 % of 4‐p‐nitrophenol to 4‐aminophenol in less than 100 s, which is comparable to noble metal.
NMSBA produced from NMST under the catalysis of supported H3PW12O40 and Co/Mn/Br catalytic system
Authors: He Heng , Fang Zhou‐Wen , Zhang Chao , Long Xiang‐Li
Published: November 2017

The commercial production of 2‐nitro‐4‐methylsulphonylbenzoic acid (NMSBA) is oxidizing 2‐nitro‐4‐methylsulphonyltoluene (NMST) by nitric acid catalyzed with V2O5. A heterogeneous catalytic system composed of phosphotungstic acid supported on activated carbon, Co, Mn, and Br is used to catalyze the production of NMSBA from NMST by oxygen in this paper. The experiments show that the heterogeneous catalytic system composed of HPW@C, Co, Mn, and Br is capable of speeding up the oxidation of NMST to NMSBA by oxygen and acquiring a higher NMST oxidation rate and NMSBA yield than the homogeneous H3PW12O40/Co/Mn/Br catalytic system. The best HPW@C catalyst is obtained by supporting 0.0125 g/g H3PW12O40 on carbon followed by being calcined at 220 °C for 4 h under nitrogen atmosphere. The best heterogeneous catalytic system consists of 2.38 × 10−3 g/g HPW@C, 925 ppm Br, 236 ppm cobalt, and a Mn/Co molar ratio of 2.5. The usage of phosphotungstic acid in the heterogeneous system is diminished substantially.
Transcatheter vs surgical aortic‐valve replacement in low‐ to intermediate‐surgical‐risk candidates: A meta‐analysis and systematic review
Authors: Khan Safi U. , Lone Ahmad N. , Saleem Muhammad A. , Kaluski Edo
Published: November 2017

The American and European expert documents recommend transcatheter aortic valve replacement (TAVR) for inoperable or high‐surgical‐risk patients with severe aortic stenosis. In comparison, efficacy of TAVR is relatively less studied in low‐ to intermediate‐surgical‐risk patients. We sought to discover whether TAVR can be as effective as surgical aortic valve replacement (SAVR) in low‐ to intermediate‐surgical‐risk candidates. Four randomized clinical trials (RCTs) and 8 prospective matched studies were selected using PubMed/MEDLINE, Embase, and Cochrane Library (inception: March 2017). Results were reported as random‐effects odds ratio (OR) with 95% confidence interval (CI). Among 9851 patients, analyses of RCTs showed that all‐cause mortality was comparable between TAVR and SAVR (short term, OR: 1.19, 95% CI: 0.86‐1.64, P = 0.30; mid‐term, OR: 0.97, 95% CI: 0.75‐1.26, P = 0.84; and long term, OR: 0.97, 95% CI: 0.81‐1.16, P = 0.76). The analysis restricted to matched studies showed similar outcomes. In the analysis stratified by study design, no significant differences were noted in the RCTs for stroke, whereas TAVR was better than SAVR in matched studies at short term only (OR: 0.46, 95% CI: 0.33‐0.65, P < 0.001). TAVR is associated with reduced risk of acute kidney injury and new‐onset atrial fibrillation (P < 0.05). However, increased incidence of permanent pacemaker implantation and paravalvular leaks was observed with TAVR. TAVR can provide similar mortality outcome compared with SAVR in low‐ to intermediate‐surgical‐risk patients with critical aortic stenosis. However, both procedures are associated with their own array of adverse events.
Biosynthetically Guided Structure–Activity Relationship Studies of Merochlorin A, an Antibiotic Marine Natural Product
Authors: López‐Pérez Borja , Pepper Henry P. , Ma Rong , Fawcett Benjamin J. , Pehere Ashok D. , Wei Qi , Ji Zengchun , Polyak Steven W. , Dai Huanqin , Song Fuhang , Abell Andrew D. , Zhang Lixin , George Jonathan H.
Published: November 2017

The onset of new multidrug‐resistant strains of bacteria demands continuous development of antibacterial agents with new chemical scaffolds and mechanisms of action. We present the first structure–activity relationship (SAR) study of 16 derivatives of a structurally novel antibiotic merochlorin A that were designed using a biosynthetic blueprint. Our lead compounds are active against several Gram‐positive bacteria such as Staphylococcus aureus (SA), methicillin‐resistant Staphylococcus aureus (MRSA), vancomycin‐resistant Enterococcus faecium (VRE) and Bacillus subtilis, inhibit intracellular growth of Mycobacterium bovis, and are relatively nontoxic to human cell lines. Furthermore, derivative 12 c {(±)‐(3aR,4S,5R,10bS)‐5‐bromo‐7,9‐dimethoxy‐4‐methyl‐4‐(4‐methylpent‐3‐en‐1‐yl)‐2‐(propan‐2‐ylidene)‐1,2,3,3a,4,5‐hexahydro‐6H‐5,10b‐methanobenzo[e]azulene‐6,11‐dione} was found to inhibit the growth of Bacillus Calmette–Guérin (BCG)‐infected cells at concentrations similar to rifampicin. These results outperform the natural product, underscoring the potential of merochlorin analogues as a new class of antibiotics.
Nonlinear micro‐CT based FE modeling of trabecular bone—Sensitivity of apparent response to tissue constitutive law and bone volume fraction
Authors: Sabet F.A. , Jin O. , Koric S. , Jasiuk I.
Published: November 2017

In this study, the sensitivity of the apparent response of trabecular bone to different constitutive models at the tissue level was investigated using finite element (FE) modeling based on micro‐computed tomography (micro‐CT). Trabecular bone specimens from porcine femurs were loaded under a uniaxial compression experimentally and computationally. The apparent behaviors computed using von Mises, Drucker‐Prager, and Cast Iron plasticity models were compared. Secondly, the effect of bone volume fraction was studied by changing the bone volume fraction of a trabecular bone sample while keeping the same basic architecture. Also, constitutive models' parameters of the tissue were calibrated for porcine bone, and the effects of different parameters on resulting apparent response were investigated through a parametric study. The calibrated effective tissue elastic modulus of porcine trabecular bone was 10±1.2 GPa, which is in the lower range of modulus values reported in the literature for human and bovine trabecular bones (4–23.8 GPa). It was also observed that, unlike elastic modulus, yield properties of tissue could not be uniquely calibrated by fitting an apparent response from simulations to experiments under a uniaxial compression. Our results demonstrated that using these 3 tissue constitutive models had only a slight effect on the apparent response. As expected, there was a significant change in the apparent response with varying bone volume fraction. Also, both apparent modulus and maximum stress had a linear relation with bone volume fraction.
Synthesis and Characterization of Tb‐Doped Nanoferrites
Authors: Rękorajska Aleksandra , Cichowicz Grzegorz , Cyranski Michal K. , Grden Michal , Pekala Marek , Blanchard Gary J. , Krysinski Pawel
Published: November 2017

Tb3+‐substituted superparamagnetic iron‐oxide‐based nanoparticles (NPs) that can be promising for possible multimodal drug carrier and radiotherapy are presented. These NPs were obtained using a reverse micelle template method with controlled micelle size. The atomic ratio of Tb/Fe ions was found to be very close to that expected from the stoichiometry of the reagents used. Aqueous suspensions of Tb‐doped nanoferrites are emissive with emission peaks characteristic for the Tb3+ dopant. Time‐resolved fluorescence decay data revealed two populations occupying inequivalent matrix sites. Above 80 K the Tb‐doped nanoferrites were superparamagnetic, which is a prerequisite for their use as carriers in magnetic‐field‐driven targeted therapies. The incorporation of up to 15 at.% of Tb3+ in their core resulted in a decrease of magnetization. Nevertheless, this magnetization appears to be sufficient for their use as carriers in an external magnetic field, and, of equal importance, stable isotope 159Tb3+ could be replaced by radioactive 161Tb3+, yielding multimodal NPs, suitable for conjugated therapies such as radiotherapy and magnetothermal therapy, as well as targeted drug delivery.
Physical layer security for dual‐hop FSO/RF system using generalized ΓΓ/η−μ fading channels
Authors: Kumar Ambrish , Garg Parul
Published: November 2017

We investigate the physical layer security of decode‐and‐forward–relayed free space optics (FSO)/radio frequency (RF) communication system. In this network, the eavesdropper exists after relay node and overhears RF transmission. Further, FSO being a line‐of‐sight transmission is assumed to be secure from eavesdroppers. Here, we have the Gamma‐Gamma (ΓΓ) distribution for FSO link and generalized η−μ distribution for RF link. The security for information transmission to the legitimate user in the presence of an eavesdropper is measured in terms of secrecy capacity and secrecy outage probability. Deriving the probability density function and cumulative distribution function of end‐to‐end signal‐to‐noise ratio, the closed‐form expressions for security parameters are achieved. The numerical analysis of the proposed system is done under the influence of atmospheric turbulence effects and various fading conditions. The results have been verified through simulation.
Mitral valve pressure gradient after percutaneous mitral valve repair: every beat counts
Authors: Lavall Daniel , Scheller Bruno , Werner Christian , Buob Axel , Mahfoud Felix
Published: November 2017

A patient presented with symptoms of decompensated heart failure 2 months after percutaneous mitral valve (MV) repair. Echocardiography demonstrated impaired left ventricular function with elevated MV pressure gradients and pulmonary pressures during rapid atrial fibrillation. Heart rate control was achieved by implantation of a biventricular pacemaker with subsequent His‐bundle ablation because atrial fibrillation was refractory to medical treatment. During biventricular pacing at different rates (50–110 b.p.m.), heart rate correlated positively with both MV mean pressure gradient and global longitudinal strain and negatively with stroke volume. MV pressure gradients directly translated into elevated pulmonary pressures. Thus, rate control and biventricular pacing improved cardiac haemodynamics.
Synthesis of Methylene‐Bridged Bisnaphthalenes as Building Blocks for Push–Pull Substituted Pentacenes
Authors: Wagner Frederic , Harms Klaus , Koert Ulrich
Published: November 2017

The use of cross‐coupling reactions for the synthesis of methylene‐bridged bisnaphthalenes bearing two nitro groups on one naphthalene and two amino groups on the other has been investigated. A Hauser–Heck reaction was used to prepare the substituted naphthalene building blocks. It was not possible to install a transmetallating function in the benzylic position due to side reactions with the nitro and the amino groups. A successful Suzuki reaction was achieved by using naphthyl trifluoroborates and bromomethyl naphthalenes. The resulting dinaphthyl methanes could be useful for the synthesis of push–pull substituted pentacenes.
Halo effects from agency behaviors and communion behaviors depend on social context: Why technicians benefit more from showing tidiness than nurses do
Authors: Gräf Michael , Unkelbach Christian
Published: November 2017

We investigate halo effects from agency behaviors and communion behaviors in different social contexts. According to the salient dimension model, attributes elicit halo effects on the ratings of other, unrelated attributes when they are relevant in a situation. Given that communion behaviors are more relevant in social and care‐related jobs, they should elicit stronger halo effects than agency behaviors in this context. In the context of scientific and technical jobs, this difference should be weakened or even reversed. Three experiments support the predicted interaction of context and behavior on halo effects. This interaction was stronger for negative than for positive behaviors. These results have implications for understanding the basic processes of halo effects as well as their real‐world effects in job‐related contexts.
Chemical Glycosylations for the Synthesis of Building Units of Post‐Translational Modifications
Authors: Shirinfar Bahareh , Ahmed Nisar
Published: November 2017

In chemical glycosylation reactions, a glycosyl donor couples with a glycosyl acceptor through glycosidic linkage. Most of the products end up with a mixture due to the formation of a stereogenic center at the anomeric carbon. Activation with a suitable Lewis acid and introduction of the non‐participating protecting group on donor and acceptor results in a selective product. Herein, we used a suitably protected donor and acceptor which produced an orthogonally protected building block with α‐selectivity. We used also a donor for the synthesis of modified phosphoribosylated amino acid. The formation of glycoside products can be used to synthesize complex biologically important organic molecules.
Framing Smallholder Irrigation in a New Business Context
Authors: Madramootoo Chandra A.
Published: November 2017

Smallholder irrigators in large publicly funded irrigation schemes are poorly linked to markets and input supplies of fertilizers, seeds, machinery, pumps, etc., as well as to credit and extension services. Consequently, there is very low crop water productivity and large amounts of water wasted in smallholder irrigation. A new irrigation business model is proposed, which is linked to markets and value chains. In addition, the business model incorporates aspects of capacity building, innovation and entrepreneurship in the rural sector. It is hoped that through application of this irrigation business model, vastly improved water use efficiency, as well as higher incomes and economic benefits, can be realized by smallholder irrigators. Copyright © 2017 John Wiley & Sons, Ltd.
Comparison of subchronic immunotoxicity of four different types of aluminum‐based nanoparticles
Authors: Park Eun‐Jung , Lee Sang Jin , Lee Gwang‐Hee , Kim Dong‐Wan , Yoon Cheolho , Lee Byoung‐Seok , Kim Younghun , Chang Jaerak , Lee Kyuhong
Published: November 2017

Nanoparticles (NPs) have recently emerged as an inhalable pollutant, owing to their applications, aluminum‐based NPs (Al‐NPs) have been prioritized for toxicity testing. In the current study, we compared the pulmonary biopersistence and subsequent toxicity of four different types of Al‐NPs (two rod‐type aluminum oxide NPs [AlONPs] with different aspect ratios [short (S)‐ and long (L)‐AlONPs], spherical aluminum cerium oxide NPs [AlCeO3, AlCeONPs] and spherical γ‐aluminum oxide hydroxide nanoparticles [AlOOHNPs]) 13weeks after a single intratracheal instillation, considering the importance of their properties in their toxicity. We found that the pulmonary biopersistence of Al‐NPs was strengthened by a high aspect ratio in the rod‐type AlONPs and by the presence of hydroxyl groups in the spherical‐type Al‐NPs. The highest toxicity was observed in the mice treated with AlOOHNPs, which showed low biostability. More importantly, we identified that the commercially available AlCeONPs were Al2O3‐coated CeO2 NPs, but not AlCeO3 NPs, although they have been sold under the trade name of AlCeONPs. In conclusion, the aspect ratio and biostability may be important factors in the determination of the biopersistence of NPs and the subsequent biological response. In addition, the physicochemical properties of NPs should be examined in detail before their release into the market to prevent unexpected adverse health effects.
Hemolysis and IgA‐antibodies against tissue transglutaminase: When are antibody test results no longer reliable?
Authors: Wolf Johannes , Haendel Norman , Remmler Johannes , Kutzner Carl Elias , Kaiser Thorsten , Mothes Thomas
Published: November 2017

Background

Antibodies against tissue transglutaminase (TTG) of isotype IgA (IgA‐aTTG) represent reliable diagnostic markers to confirm or exclude celiac disease (CD). Hemolysis (HL) is an important pre‐analytical factor. HL can be quantified as HL index (HI) correlating with the concentration of free hemoglobin. TTG is abundant in erythrocytes and released upon HL. In immunoassays, the released TTG may interfere with binding of IgA‐aTTG to the coated TTG.

Methods

We selected 17 HL‐free sera from children with biopsy‐confirmed CD: 7 with low‐positive (1‐5 multiples of upper limit of normal [×ULN]), 5 with intermediate (5‐10 × ULN) and 5 with high IgA‐aTTG (10‐15 × ULN). Sera were spiked with hemolysates resulting in HIs ranging from 12.5 to 800 (12.5‐800 mg/dL free hemoglobin).

Results

IgA‐aTTG values were significantly decreased (>10%) after addition of hemolysates even if HL was invisible (HI <50). This effect is diagnosis‐relevant if IgA‐aTTG values are measured just below the cut‐offs: (i) 0.4‐1 × ULN at HI ≥25 (CD not excludable) and (ii) 8.5‐10 × ULN at HI ≥200 (diagnosis of CD without biopsy not possible). Antibodies against deamidated gliadin were not influenced by HL.

Conclusions

IgA‐aTTG results in sera with HI ≥25 can yield inconclusive results. Therefore, those antibody results should be assessed only under consideration of the HI.
χ‐bounds, operations, and chords
Authors: Trotignon Nicolas , Pham Lan Anh
Published: November 2017

A long unichord in a graph is an edge that is the unique chord of some cycle of length at least 5. A graph is long unichord free if it does not contain any long unichord. We prove a structure theorem for long unichord free graph. We give an time algorithm to recognize them. We show that any long unichord free graph G can be colored with at most colors, where ω is the maximum number of pairwise adjacent vertices in G.