bluuebunny/crossref_metadata_2025 huggingface dataset:
Mass Determination of Entire Amyloid Fibrils by Using Mass Spectrometry
Authors: Doussineau Tristan , Mathevon Carole , Altamura Lucie , Vendrely Charlotte , Dugourd Philippe , Forge Vincent , Antoine Rodolphe
Published: December 2015

Amyloid fibrils are self‐assembled protein structures with important roles in biology (either pathogenic or physiological), and are attracting increasing interest in nanotechnology. However, because of their high aspect ratio and the presence of some polymorphism, that is, the possibility to adopt various structures, their characterization is challenging and basic information such as their mass is unknown. Here we show that charge‐detection mass spectrometry, recently developed for large self‐assembled systems such as viruses, provides such information in a straightforward manner.
Ionic Covalent Organic Frameworks with Spiroborate Linkage
Authors: Du Ya , Yang Haishen , Whiteley Justin Michael , Wan Shun , Jin Yinghua , Lee Se‐Hee , Zhang Wei
Published: December 2015

A novel type of ionic covalent organic framework (ICOF), which contains sp3 hybridized boron anionic centers and tunable countercations, was constructed by formation of spiroborate linkages. These ICOFs exhibit high BET surface areas up to 1259 m2 g−1 and adsorb a significant amount of H2 (up to 3.11 wt %, 77 K, 1 bar) and CH4 (up to 4.62 wt %, 273 K, 1 bar). Importantly, the materials show good thermal stabilities and excellent resistance to hydrolysis, remaining nearly intact when immersed in water or basic solution for two days. The presence of permanently immobilized ion centers in ICOFs enables the transportation of lithium ions with room‐temperature lithium‐ion conductivity of 3.05×10−5 S cm−1 and an average Li+ transference number value of 0.80±0.02. Our approach thus provides a convenient route to highly stable COFs with ionic linkages, which can potentially serve as absorbents for alternative energy sources such as H2, CH4, and also as solid lithium electrolytes/separators for the next‐generation lithium batteries.
Automated arabic text classification with P‐Stemmer, machine learning, and a tailored news article taxonomy
Authors: Kanan Tarek , Fox Edward A.
Published: December 2015

Arabic news articles in electronic collections are difficult to study. Browsing by category is rarely supported. Although helpful machine‐learning methods have been applied successfully to similar situations for English news articles, limited research has been completed to yield suitable solutions for Arabic news. In connection with a Qatar National Research Fund (QNRF)‐funded project to build digital library community and infrastructure in Qatar, we developed software for browsing a collection of about 237,000 Arabic news articles, which should be applicable to other Arabic news collections. We designed a simple taxonomy for Arabic news stories that is suitable for the needs of Qatar and other nations, is compatible with the subject codes of the International Press Telecommunications Council, and was enhanced with the aid of a librarian expert as well as five Arabic‐speaking volunteers. We developed tailored stemming (i.e., a new Arabic light stemmer called P‐Stemmer) and automatic classification methods (the best being binary Support Vector Machines classifiers) to work with the taxonomy. Using evaluation techniques commonly used in the information retrieval community, including 10‐fold cross‐validation and the Wilcoxon signed‐rank test, we showed that our approach to stemming and classification is superior to state‐of‐the‐art techniques.
Disentangling the urbanization effect, multi‐decadal variability, and secular trend in temperature in eastern China during 1909–2010
Authors: Qian Cheng
Published: December 2015

Understanding surface air temperature (SAT) changes in China during the past 100 years is important; however, this is difficult because the impacts of multi‐decadal variability (MDV), the urbanization effect, and other anthropogenic forcings are combined in instrumental records. The present study attempts to disentangle these factors recorded in observations in eastern China based on recently homogenized SAT data during 1909–2010. The estimated linear trend (secular nonlinear trend) in the data after deurbanization is 1.08 (1.74)°C (100 years)−1. The MDV has enhanced warming in the early 20th century and during the past 30 years, contributing approximately 30% to the latter period.
Inference for low‐ and high‐dimensional multigroup repeated measures designs with unequal covariance matrices
Authors: Happ Martin , Harrar Solomon W. , Bathke Arne C.
Published: December 2015

We propose tests for main and simple treatment effects, time effects, as well as treatment by time interactions in possibly high‐dimensional multigroup repeated measures designs. The proposed inference procedures extend the work by Brunner et al. (2012) from two to several treatment groups and remain valid for unbalanced data and under unequal covariance matrices. In addition to showing consistency when sample size and dimension tend to infinity at the same rate, we provide finite sample approximations and evaluate their performance in a simulation study, demonstrating better maintenance of the nominal α‐level than the popular Box‐Greenhouse–Geisser and Huynh–Feldt methods, and a gain in power for informatively increasing dimension. Application is illustrated using electroencephalography (EEG) data from a neurological study involving patients with Alzheimer's disease and other cognitive impairments.
Self‐Assembly and Characterization of Three‐Dimensional Silver(I) Coordination Polymers Containing N,N,N′,N′‐Tetrakis(pyridin‐4‐yl)methanediamine
Authors: Shin Jong Won , Min Kil Sik
Published: December 2015

Silver(I) coordination polymers, [Ag(tpmd)](NO3
)·2CH3OH (1), [Ag(tpmd)](CF3SO3
) (2), and [Ag(tpmd)](CF3CO2
)·0.5CH3OH (3), have been obtained by the self‐assembly of AgX (X = NO3

−, CF3SO3

−, CF3CO2

−) and N,N,N′,N′‐tetrakis(pyridin‐4‐yl)methanediamine (tpmd) in MeOH/MeCN. The coordination geometries of silver(I) ions in 1 and 2 are distorted tetrahedral structures, while that of 3 is a distorted trigonal bipyramid. 1 and 2 feature three‐dimensional coordination polymers formed by coordination of the silver(I) ions to the tpmd ligands. 3 shows two‐dimensional network basically. However, the network of 3 can be considered three‐dimensional structure by the weak axial bonding of the fourth pyridine group from another tpmd ligand. 1–3 display strong emissions at 331, 342, and 326 nm, respectively.
Kinetic Study on Nucleophilic Displacement Reactions of Phenyl Y‐Substituted Phenyl Carbonates with 1,8‐Diazabicyclo[5.4.0]undec‐7‐ene: Effects of Amine Nature on Reaction Mechanism
Authors: Park Kyoung‐Ho , Kim Min‐Young , Um Ik‐Hwan
Published: December 2015

Second‐order rate constants (k
N) for nucleophilic displacement reactions of phenyl Y‐substituted phenyl carbonates (7a–7l) with 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU) in 80 mol % H2O/20 mol % DMSO at 25.0 ± 0.1 oC have been measured spectrophotometrically. The Brønsted‐type plot for the reactions of 7a–7l with DBU is linear with βlg = –0.48, indicating that the reactions proceed through a concerted mechanism, which is in contrast to the stepwise mechanism reported previously for the corresponding reactions with ethylamine (a primary amine) and piperidine (a secondary amine). The Hammett plots correlated with σ
− and σ
o constants exhibit many scattered points. In contrast, the Yukawa–Tsuno plot results in an excellent linear correlation with ρY = 1.27 and r = 0.57, implying that a negative charge develops partially on the O atom of the leaving group in the transition state. The bulky DBU is less reactive than the primary and secondary amines toward substrates possessing a weakly basic leaving group. It has been concluded that steric hindrance exerted by DBU in the plausible intermediate (T±) forces the reactions to proceed through a concerted mechanism because expulsion of the leaving group from T± could reduce the steric hindrance.
A CatalyCEST MRI Contrast Agent that Can Simultaneously Detect Two Enzyme Activities
Authors: Fernández‐Cuervo Gabriela , Sinharay Sanhita , Pagel Mark D.
Published: December 2015

The simultaneous detection of multiple enzyme activities can improve the specificity of disease diagnoses. We therefore synthesized and characterized a diamagnetic chemical exchange saturation transfer (CEST) MRI contrast agent that can simultaneously detect two enzyme activities. Sulfatase and esterase enzymes cleave the ligands of the CEST agent, releasing salicylic acid that can be detected with CEST MRI. Importantly, both enzymes are required to activate the agent to produce a CEST MRI contrast, and the CEST agent was stable without enzyme treatment. These results established that this diamagnetic CEST MRI contrast agent is a platform technology with a modular design that can be potentially exploited to detect other combinations of enzyme activities, which can expand the armamentarium of contrast agents for molecular imaging.
Expression of osteoclastogenic factor transcripts in osteoblast‐like UMR‐106 cells after exposure to FGF‐23 or FGF‐23 combined with parathyroid hormone
Authors: Teerapornpuntakit Jarinthorn , Wongdee Kannikar , Krishnamra Nateetip , Charoenphandhu Narattaphol
Published: December 2015

As a bone‐derived hormone, fibroblast growth factor‐23 (FGF‐23) negatively regulates phosphate and calcium metabolism, while retaining growth‐promoting action for mesenchymal cell differentiation. Elevated FGF‐23 levels, together with hyperparathyroidism, are often observed in chronic kidney disease, which is associated with impaired bone mineralization and enhanced bone resorption. Although overexpression of osteoblast‐derived osteoclastogenic cytokines might contribute to this metabolic bone disease, whether FGF‐23 alone and FGF‐23 plus parathyroid hormone (PTH) directly modulated the expression of osteoblast‐derived osteoclastogenic genes remained elusive. Herein, we demonstrated the direct effects of FGF‐23 on proliferation and mRNA expression of osteoblast‐specific differentiation and osteoclastogenic markers in rat osteoblast‐like UMR‐106 cells in the presence or absence of PTH. FGF‐23 was found to suppress UMR‐106 cell proliferation, while increasing FGF‐23 expression, the latter of which suggested the presence of positive feedback regulation of FGF‐23 expression in osteoblasts. FGF‐23 also upregulated the mRNA expression of osteoblast differentiation markers (e.g., Runx2, osterix, AJ18, Dlx5, alkaline phosphatase, and osteopontin), osteoclastogenic factors (e.g., MCSF, MCP‐1, IL‐6, and TNF‐α), and bone resorption regulators (RANKL and osteoprotegerin). However, combined PTH and FGF‐23 exposure did not alter the levels of FGF‐23‐induced transcripts, suggesting that both hormones had no additive effect. In conclusion, FGF‐23 directly suppressed osteoblast proliferation, while inducing osteoclastogenic gene expression in UMR‐106 cells, and the FGF‐23‐induced transcripts were not altered by long‐standing PTH exposure.
Transcatheter aortic valve replacement versus surgical aortic valve replacement in patients with cirrhosis
Authors: Thakkar Badal , Patel Aashay , Mohamad Bashar , Patel Nileshkumar J. , Bhatt Parth , Bhimani Ronak , Patel Achint , Arora Shilpkumar , Savani Chirag , Solanki Shantanu , Sonani Rajesh , Patel Samir , Patel Nilay , Deshmukh Abhishek , Mohamad Tamam , Grines Cindy , Cleman Michael , Mangi Abeel , Forrest John , Badheka Apurva O.
Published: December 2015

Objectives

To compare the in‐hospital outcomes in cirrhosis patients undergoing transcatheter aortic valve replacement (TAVR) versus those undergoing surgical aortic valve replacement (SAVR).

Background

Over the last 10 years, TAVR has emerged as a therapeutic option for treating severe aortic stenosis in high‐risk patients. Cirrhosis patients have a high risk of operative morbidity and mortality while undergoing cardiac surgery. This study's hypothesis was that TAVR is a safer alternative compared to SAVR in cirrhosis patients.

Methods

The study population was derived from the National Inpatient Sample (NIS) for the years 2011–2012 using ICD‐9‐CM procedure codes 35.21 and 35.22 for SAVR, and 35.05 and 35.06 for TAVR. Patients <50 years of age and those who concomitantly underwent other valvular procedures were excluded. ICD‐9‐CM diagnosis codes were used to identify patients with liver cirrhosis, portal hypertension, and esophageal varices. Using propensity score matching, two matched cohorts were derived in which the outcomes were compared using appropriate statistical tests.

Results

There were 30 patients in the SAVR and TAVR group each. Compared to the TAVR group, the patients in SAVR group had significantly higher rate of transfusion of whole blood or blood products (p = 0.037), longer mean postprocedural length of stay (p = 0.006), and nonsignificantly higher mean cost of hospitalization (p = 0.2), any complications rate (p = 0.09), and liver complications rate (p = 0.4). In‐hospital mortality rate was same in the both the groups. No patients in the TAVR group required open‐heart surgery or cardiopulmonary bypass.

Conclusion

TAVR could be a viable option for aortic valve replacement in cirrhosis patients. © 2015 Wiley Periodicals, Inc.
Transcatheter valve‐in‐ring implantation of a repositionable valve system for treatment of severe mitral regurgitation
Authors: Lauterbach Michael , Sontag Bruno , Paraforos Alexandros , Friedrich Ivar , Hauptmann Karl‐Eugen
Published: December 2015

Introduction

Years after mitral valve surgery, progressive degeneration of reconstructed mitral valves or bioprostheses might lead to severe mitral valve regurgitation. Patients with significant comorbidity, or impaired left ventricular function are poor candidates for redo surgery at an acceptable risk at that later time point.

Methods and results

This study reports the first‐in‐man transapical valve‐in‐ring implantations in the mitral position of the fully repositionable Lotus valve system approved for transcatheter aortic valve replacement in Europe. Transapical valve‐in‐ring implantations with this valve system were successfully performed in a 64‐year‐old female, and a 53‐year‐old male patient. Both patients were NHYA class IV, and carried an unacceptably high risk of cardiac surgery due to clinical condition and comorbidity. The first patient was successfully implanted a 25 mm valve, improved to NYHA class II, and was discharged 2 weeks after the procedure. The second patient required a short episode of cardiopulmonary resuscitation after valve implantation (27 mm), and was placed on veno‐venous ECMO for 24 hr to improve oxygenation. He developed stroke on day 7, and deceased from fatal, toxic rhabdomyolysis 13 days after the procedure.

Conclusion

Transapical valve‐in‐ring implantation of the repositionable Lotus valve system in the mitral position is a feasible and promising option that merits further evaluation. © 2015 Wiley Periodicals, Inc.
High‐dimensional quantitative structure–activity relationship modeling of influenza neuraminidase a/PR/8/34 (H1N1) inhibitors based on a two‐stage adaptive penalized rank regression
Authors: Algamal Zakariya Yahya , Lee Muhammad Hisyam , Al‐Fakih Abdo Mohammed
Published: December 2015

Outliers in the biological activity variable or the heavy tailed distribution of the error are often encountered in practice. Under these circumstances, the quantittative structure–activity relationship (QSAR) model using multiple linear regression is not efficient. In this paper, a two‐stage adaptive penalized rank regression is proposed for constructing a robust and efficient high‐dimensional QSAR model of influenza virus neuraminidase A/PR/8/34 (H1N1) inhibitors. The results demonstrate the effectiveness of our proposed method in simultaneously estimating a robust QSAR model and selecting informative molecular descriptors. Furthermore, the results prove that the proposed method can significantly encourage the grouping effect. The proposed method, because of the high predictive ability and robustness, could be a useful method in high‐dimensional QSAR modeling. Copyright © 2015 John Wiley & Sons, Ltd.
Quantum Mechanics/Molecular Mechanics Modeling of Enzymatic Processes: Caveats and Breakthroughs
Authors: Quesne Matthew G. , Borowski Tomasz , de Visser Sam P.
Published: December 2015

Nature has developed large groups of enzymatic catalysts with the aim to transfer substrates into useful products, which enables biosystems to perform all their natural functions. As such, all biochemical processes in our body (we drink, we eat, we breath, we sleep, etc.) are governed by enzymes. One of the problems associated with research on biocatalysts is that they react so fast that details of their reaction mechanisms cannot be obtained with experimental work. In recent years, major advances in computational hardware and software have been made and now large (bio)chemical systems can be studied using accurate computational techniques. One such technique is the quantum mechanics/molecular mechanics (QM/MM) technique, which has gained major momentum in recent years. Unfortunately, it is not a black‐box method that is easily applied, but requires careful set‐up procedures. In this work we give an overview on the technical difficulties and caveats of QM/MM and discuss work‐protocols developed in our groups for running successful QM/MM calculations.
Small‐Molecule and Peptide Inhibitors of the Pro‐Survival Protein Mcl‐1
Authors: Beekman Andrew M. , Howell Lesley A.
Published: December 2015

The ability of protein–protein interactions to regulate cellular processes in both beneficial and detrimental ways has made them obvious drug targets. The Bcl‐2 family of proteins undergo a series of protein–protein interactions which regulate the intrinsic cell‐death pathway. The pro‐survival members of the Bcl‐2 family, including Bcl‐2, Bcl‐xL, and Mcl‐1, are commonly overexpressed in a number of human cancers. Effective modulators of members of the Bcl‐2 family have been developed and are undergoing clinical trials, but the efficient modulation of Mcl‐1 is still not represented in the clinic. In addition, Mcl‐1 is a major cause of resistance to radio‐ and chemotherapies, including inhibitors that target other Bcl‐2 family members. Subsequently, the inhibition of Mcl‐1 has become of significant interest to the scientific community. This review covers the progress made to date in modulating the activity of Mcl‐1, by both stapled peptides and small molecules. The development of peptides as drug candidates, and the advancement of experimental and computational techniques used to discover small molecules are also highlighted.
An optimized GPU‐based 2D convolution implementation
Authors: Perrot Gilles , Domas Stéphane , Couturier Raphaël
Published: December 2015

With the increasing sophistication of image processing algorithms, and because of its low computation complexity, convolution should fully benefit from the ever‐increasing capacities of state‐of‐the‐art graphics processing units, such as Nvidia's Kepler and Maxwell family cards. Currently, it tends to be used as a preprocessing stage within more intricate image manipulations and has recently been implemented quite efficiently by several teams. However, either their implementations do not come near hardware's peak performance or are unable to process large mask sizes. Such limitations are overrun by our original parallel register‐only convolution filter implementation of two‐dimensional convolution filters that can process 32‐bit floating‐point images on a NVidia K40 card using mask sizes up to 127×127 and at the same time achieving pixel throughputs over 29GP/s, which is, as far as we know, the highest rate known to date. Such results were obtained by using registers sparingly and by designing memory access patterns that cancel both load and store replays at warp levels, along with optimizing cache use. Copyright © 2015 John Wiley & Sons, Ltd.
Artificial Formation and Tuning of Glycoprotein Networks on Live Cell Membranes: A Single‐Molecule Tracking Study
Authors: Möckl Leonhard , Lindhorst Thisbe K. , Bräuchle Christoph
Published: December 2015

We present a method to artificially induce network formation of membrane glycoproteins and show the precise tuning of their interconnection on living cells. For this, membrane glycans are first metabolically labeled with azido sugars and then tagged with biotin by copper‐free click chemistry. Finally, these biotin‐tagged membrane proteins are interconnected with streptavidin (SA) to form an artificial protein network in analogy to a lectin‐induced lattice. The degree of network formation can be controlled by the concentration of SA, its valency, and the concentration of biotin on membrane proteins. This was verified by investigation of the spatiotemporal dynamics of the SA‐protein networks employing single‐molecule tracking. It was also proven that this network formation strongly influences the biologically relevant process of endocytosis as it is known from natural lattices on the cell surface.
Elucidation of the CO‐Release Kinetics of CORM‐A1 by Means of Vibrational Spectroscopy
Authors: Klein Moritz , Neugebauer Ute , Schmitt Michael , Popp Jürgen
Published: December 2015

CO‐releasing molecules (CORMs) are developed for investigations of the interaction between the signaling molecule carbon monoxide (CO) and cells or tissue. Prior to their application these molecules must be fully characterized with respect to their CO‐release mechanism. One widely used CORM for biological application is sodium boranocarbonate (CORM‐A1), which shows pH‐dependent CO liberation. The complete reaction mechanism of CORM‐A1 is not fully understood yet. Therefore, in this contribution time‐resolved gas‐phase IR spectroscopy is used to monitor the headspace above decaying CORM‐A1 solutions at four different pH values (5.8 to 7.4). Borane carbonyl is found as an intermediate in the gas phase, which is formed during CORM degradation and further decays to CO. Concentration profiles of a pseudoconsecutive first‐order reaction are successfully fitted to specific band areas of the measured gas‐phase spectra, and the rate constants are obtained. The production of borane carbonyl is strongly pH dependent (half‐lives between 5 and 106 min), whereas the decay of borane carbonyl in the gas phase is nearly constant with a half‐life of about 33 min. The ratio of liberated CO molecules per CORM‐A1 is determined to be 0.91±0.09, and boric acid is identified as further end product.
Ultrafast Magic‐Angle Spinning: Benefits for the Acquisition of Ultrawide‐Line NMR Spectra of Heavy Spin‐ Nuclei
Authors: Pöppler Ann‐Christin , Demers Jean‐Philippe , Malon Michal , Singh Amit Pratap , Roesky Herbert W. , Nishiyama Yusuke , Lange Adam
Published: December 2015

The benefits of the ultrafast magic‐angle spinning (MAS) approach for the acquisition of ultrawide‐line NMR spectra—spectral simplification, increased mass sensitivity allowing the fast study of small amounts of material, efficient excitation, and application to multiple heavy nuclei—are demonstrated for tin(II) oxide (SnO) and the tin complex [(LB)SnIICl]+[SnIICl3]− [LB=2,6‐diacetylpyridinebis(2,6‐diisopropylanil)] containing two distinct tin environments. The ultrafast MAS experiments provide optimal conditions for the extraction of the chemical‐shift anisotropy tensor parameters, anisotropy, and asymmetry for heavy spin‐
nuclei.
Optimizing the initial setting of complex adaptive systems–optimizing the layout of initial AFVs stations for maximizing the diffusion of AFVs
Authors: Zhao Jiangjiang , Ma Tieju
Published: December 2015

There are occasions when people want to optimize the initial setting of a CAS (complex adaptive system) so that it evolves in a desired direction. A CAS evolves by heterogeneous actors interacting with each other. It is difficult to describe the evolution process with an objective function. Researchers usually attempt to optimize an intervening objective function, which is supposed to help a CAS evolve in a desired direction. This article puts forward an approach to optimize the initial setting of a CAS directly (instead of through an intervening objective function) by nesting agent‐based simulations in a genetic algorithm. In the approach, an initial setting of a CAS is treated as a genome, and its fitness is defined by the closeness between the simulation result and the desired evolution. We test the applicability of the proposed approach on the problem of optimizing the layout of initial AFV (alternative fuel vehicle) refueling stations to maximize the diffusion of AFVs. Computation experiments show that the initial setting generated with the approach could better induce the desired evolving result than optimizing an intervening objective function. The idea of the approach can also be applied to other decision making associated with a complex adaptive process. © 2015 Wiley Periodicals, Inc. Complexity 21: 275–290, 2016
A survey of IEEE 802.15.4 effective system parameters for wireless body sensor networks
Authors: Moravejosharieh Amirhossein , Lloret Jaime
Published: December 2015

Wireless body sensor networks are offered to meet the requirements of a diverse set of applications such as health‐related and well‐being applications. For instance, they are deployed to measure, fetch and collect human body vital signs. Such information could be further used for diagnosis and monitoring of medical conditions. IEEE 802.15.4 is arguably considered as a well‐designed standard protocol to address the need for low‐rate, low‐power and low‐cost wireless body sensor networks. Apart from the vast deployment of this technology, there are still some challenges and issues related to the performance of the medium access control (MAC) protocol of this standard that are required to be addressed. This paper comprises two main parts. In the first part, the survey has provided a thorough assessment of IEEE 802.15.4 MAC protocol performance where its functionality is evaluated considering a range of effective system parameters, that is, some of the MAC and application parameters and the impact of mutual interference. The second part of this paper is about conducting a simulation study to determine the influence of varying values of the system parameters on IEEE 802.15.4 performance gains. More specifically, we explore the dependability level of IEEE 802.5.4 performance gains on a candidate set of system parameters. Finally, this paper highlights the tangible needs to conduct more investigations on particular aspect(s) of IEEE 802.15.4 MAC protocol. Copyright © 2015 John Wiley & Sons, Ltd.
Two Coordination Polymers and Their Silver(I)‐Doped Species: Synthesis, Characterization, and High Catalytic Activity for the Photodegradation of Various Organic Pollutants in Water
Authors: Chen Min‐Min , Li Hong‐Xi , Lang Jian‐Ping
Published: December 2015

Solvothermal reactions of M(NO3)2 (M = Cd, Co) with isophthalic acid (1,3‐H2bdc) and N‐(pyridin‐2‐yl)‐N‐{4‐[2‐(pyridin‐4‐yl)vinyl]phenyl}pyridin‐2‐amine (ppvppa) at 150 °C afforded two two‐dimensional (2D) coordination polymers (CPs) [M(ppvppa)2(1,3‐bdc)]·xH2O [M = Cd, x = 2 (1·2H2O); M = Co, x = 1.5 (2·1.5H2O)]. In 1 and 2, the uncoordinated di(pyridin‐2‐yl)amine of ppvppa can further bind additional metal ions. Their AgI‐doped polymers, [Cd(ppvppa)2(1,3‐bdc)]·AgNO3 (1a) and [Co(ppvppa)2(1,3‐bdc)]·0.75AgNO3 (2a), were obtained by immersing 1 and 2, respectively, into an aqueous solution of AgNO3. Compared with 1 and 2, 1a and 2a exhibited greatly enhanced catalytic activity towards the photodegradation of RhB, Acid Red 27, and theophylline in water due to their narrower band gaps. For 2a, the apparent rate constants for the photodecomposition of the three pollutants are around 4.4, 2.3, or 1.76 times larger than those of 2, respectively. The results provide an insight into a metal‐ion doping strategy that can narrow the band gaps of the CPs and thus greatly improve their photocatalytic performance in degrading organic pollutants in water.
Solids Go Bio: Inorganic Nanoparticles as Enzyme Mimics
Authors: Ragg Ruben , Tahir Muhammad N. , Tremel Wolfgang
Published: December 2015

A longstanding goal of biomimetic chemistry is the design and synthesis of functional enzyme mimics. The past three decades have seen a wide variety of materials, including metal complexes, polymers and other biomolecules, that mimic the structures and functions of naturally occurring enzymes. Among these, inorganic nanoparticles offer huge potential, because they are more stable than their natural counterparts, while having large surface areas and sizes comparable to those of natural enzymes. Therefore, a considerable number of “artificial enzymes” derived from inorganic nanomaterials have been reported. This microreview highlights the recent progress in the field of enzymatically active inorganic nanomaterials, including mimics of peroxidases, haloperoxidases, superoxide dismutases and sulfite oxidases, along with selected biotechnological applications and their future prospects.
Spectroscopic and Computational Investigation of Low‐Spin MnIII Bis(scorpionate) Complexes
Authors: Colmer Hannah E. , Margarit Charles G. , Smith Jeremy M. , Jackson Timothy A. , Telser Joshua
Published: December 2015

Six‐coordinate MnIII complexes are typically high‐spin (S = 2), however, the scorpionate ligand, both in its traditional, hydridotris(pyrazolyl)borate form, Tp– and Tp*– (the latter with 3,5‐dimethylpyrazole substituents) and in an aryltris(carbene)borate (i.e., N‐heterocyclic carbene, NHC) form, [Ph(MeIm)3B]–, (MeIm = 3‐methylimidazole) lead to formation of bis(scorpionate) complexes of MnIII with spin triplet ground states; three of which were investigated herein: [Tp2Mn]SbF6 (1SbF6), [Tp*2Mn]SbF6 (2SbF6), and [{Ph(MeIm)3B}2Mn]CF3SO3 (3CF3SO3). These trigonally symmetric complexes were studied experimentally by magnetic circular dichroism (MCD) spectroscopy (the propensity of 3 to oxidize to MnIV precluded collection of useful MCD data) including variable temperatures and fields (VTVH‐MCD) and computationally by ab initio CASSCF/NEVPT2 methods. These combined experimental and theoretical techniques establish the 3A2g electronic ground state for the three complexes, and provide information on the energy of the “conventional” high‐spin excited state (5Eg) and other, triplet excited states. These results show the electronic effect of pyrazole ring substituents in comparing 1 and 2. The tunability of the scorpionate ligand, even by perhaps the simplest change (from pyrazole in 1 to 3,5‐dimethylpyrazole in 2) is quantitatively manifested through perturbations in ligand‐field excited‐state energies that impact ground‐state zero‐field splittings. The comparison with the NHC donor is much more dramatic. In 3, the stronger σ‐donor properties of the NHC lead to a quantitatively different electronic structure, so that the lowest lying spin triplet excited state, 3Eg, is much closer in energy to the ground state than in 1 or 2. The zero‐field splitting (zfs) parameters of the three complexes were calculated and in the case of 1 and 2 compare closely to experiment (lower by < 10 %, < 2 cm–1 in absolute terms); for 3 the large magnitude zfs is reproduced, although there is ambiguity about its sign. The comprehensive picture obtained for these bis(scorpionate) MnIII complexes provides quantitative insight into the role played by the scorpionate ligand in stabilizing unusual electronic structures.
Thermal and Light‐Induced Spin Transitions of FeII Complexes with 4‐ and 5‐(Phenylazo)‐2,2′‐bipyridine Ligands: Intra‐ vs. Intermolecular Effects
Authors: Schmidt Sven Olaf , Naggert Holger , Buchholz Axel , Brandenburg Hannah , Bannwarth Alexander , Plass Winfried , Tuczek Felix
Published: December 2015

Five new spin crossover complexes with 4‐ and 5‐(phenylazo)‐2,2‐bipyridine (4‐/5‐PAbipy) ligands were synthesized and investigated with respect to their spin crossover (SCO) behavior. The results are compared to the thermal and light‐induced spin transition properties of the parent SCO complexes [Fe(bpz)2(bipy)] (1) and [Fe(bipy)2(NCS)2] (2). [Fe(bpz)2(4‐PAbipy)] (1a) undergoes a stepwise spin transition whereas [Fe(bpz)2(5‐PAbipy)] (1b) exhibits a one‐step transition with a 6 K‐wide hysteresis. For [Fe(bpz)2(tBu5‐PAbipy)] (1c) the spin transition to the low‐spin state is incomplete. Qualitatively similar changes of the SCO behavior are observed for the complexes [Fe(4‐PAbipy)2(NCS)2] (2a) and [Fe(5‐PAbipy)2(NCS)2] (2b). In comparison to the parent system 2, a strengthening of intermolecular interactions leads to a stabilization of the low‐spin state. Evidence for the LIESST behavior could be obtained for all new compounds by means of magnetic susceptibility measurements as well as UV/Vis and resonance Raman spectroscopy.
Xanthones with pancreatic lipase inhibitory activity from the pericarps of Garcinia mangostana L. (Guttiferae)
Authors: Chae Hee‐Sung , Kim Eun‐Young , Han Ling , Kim Na‐Rae , Lam Bunthoeun , Paik Jin Hyub , Yoon Kee Dong , Choi Young Hee , Chin Young‐Won
Published: December 2015

Bioactivity‐guided isolation of natural compounds from the pericarps of Garcinia mangostana, using a pancreatic lipase assay, led to the identification of 13 xanthones including α‐mangostin (1), β‐mangostin (2), γ‐mangostin (3), 1‐isomangostin (4), gartanin (5), garcinone D (6), 9‐hydroxycalabaxanthone (7), smeathxanthone A (8), tovophyllin A (9), 8‐ deoxygartanin (10), mangostanin (11), calocalabaxanthone (12), and 1,7‐dihydroxy‐3‐methoxy‐2‐(3‐methylbut‐2‐enyl) xanthen‐9‐one (13). The inhibitory activities of the isolated xanthones against pancreatic lipase were evaluated and α‐mangostin (1) was found to possess the most potent inhibitory activity (IC50 5.0 µM) in a non‐competitive manner, compared with the positive control, orlistat (IC50 3.9 µM).

Practical applications: Pancreatic lipase is a key enzyme in lipid absorption. A total of 13 compounds were isolated from the pericarps of G. mangostana. Their structures were characterized by HRESI‐MS, and 1D and 2D‐NMR spectroscopic data. Our results show that all the isolates exhibited inhibitory activity against pancreatic lipase. Of the active xanthones, α‐mangostin displayed the most potent lipase inhibition, with an IC50 value of 5.0 μM. Furthermore, kinetic analysis of α‐mangostin was carried out. In the Lineweaver–Burk plot, the apparent Vmax values in the presence of 1, 2, 4, and 10 µM α‐mangostin were decreased compared with those without α‐mangostin, whereas the Km values of 4‐MU oleate with and without α‐mangostin were both close to 3.22 μM. Finally, it is evident that xanthone derivatives isolated from G. mangostana possess pancreatic lipase inhibitory activities.

A total of 13 compounds are isolated from the pericarps of Garcinia mangostana. α‐Mangostin is found to possess the most potent lipase inhibitory activity.
Mechanism of Ylide Transfer to ­Carbonyl Compounds: Density Functional Calculations
Authors: Patil Mahendra , Thiel Walter
Published: December 2015

We report a computational study on the mechanism of the reaction of ethyl acetoacetate (1) with two sulfur reagents: Martin's sulfurane (Ra) and a mixture of diphenyl sulfide and triflic anhydride (Rb). These reagents are able to provide a sulfonium ion [Ph2S‐OX]+ and an anionic nucleophile –OX as active species [X = C(CF3)2Ph for Ra and X = SO2CF3 for Rb] in the reaction. Experimentally, the reaction of Ra with carbonyl compounds provides an S‐ylide as the only product whereas a low yield of S‐ylide is obtained in the case of Rb. To elucidate the mechanism of these reactions with prototype substrate 1, different plausible pathways have been investigated using density functional theory (DFT), mostly at the B3LYP‐D/6‐31+G** level. According to DFT calculations, initial deprotonation of 1 may furnish either an enolate (with Ra) or an O‐sulfenylated enolate (with Rb). Subsequent nucleophilic addition of the enolate to the sulfonium ion provides the simplest route to S‐ylide product, which is favored when using reagent Ra. In the case of reagent Rb, the preferentially formed O‐sulfenylated enolate may undergo either a series of nucleophilic displacements or a [1,3] sigmatropic shift or a [3,3] sigmatropic rearrangement, all followed by a final deprotonation to yield the product. These conversions are highly exothermic and involve thermodynamically stable products. The [3,3] sigmatropic rearrangement that directly produces an arylated carbonyl compound is computed to be the kinetically most facile reaction with Rb. Overall, the computational results unveil detailed mechanistic scenarios detailing possible transformations and providing qualitative explanations for some of the experimental findings.
Starburst Triphenylamine‐Based Donor–Acceptor‐Type Small Molecules for Solution‐Processed Organic Solar Cells
Authors: Tan Hua , Peng Wenhong , Xiao Manjun , Xu Chao , Nie Kaixuan , Yu Junting , Wang Yafei , Liu Yu , Zhu Weiguo
Published: December 2015

A class of the donor–acceptor (D–A)‐type organic small molecules that includes TPA‐DPP, DTPA‐DPP, and TTPA‐DPP [TPA = triphenylamine, DPP = diketopyrrolopyrrole, DTPA = bis(triphenylamine), TTPA = tris(triphenylamine)] was synthesized; these compounds contain TPA as a donor unit and DPP as an acceptor unit. Solution‐processed organic solar cells (OSCs) with these compounds as donors and [6,6]‐phenyl‐C71‐butyric acid methyl ester (PC71BM) as an acceptor were fabricated. The starburst OSCs prepared from DTPA‐DPP and TTPA‐DPP with two and three TPA units, respectively, exhibited better photovoltaic performance than the OSC prepared with one TPA unit, because DTPA‐DPP and TTPA‐DPP have better light‐harvesting properties and charge‐transport properties. The DTPA‐DPP‐based OSCs delivered a power conversion efficiency (PCE) of 2.26 % and the TTPA‐DPP‐based OSCs exhibited a higher PCE of 2.47 %. The PCE level is 1.15 and 1.25 times higher than that in the TPA‐DPP‐based OSCs, respectively. Our work indicates that a starburst configuration can improve the photovoltaic properties of D–A‐type organic small molecules in OSCs.
Electrocatalytic Determination of Hydrazine and Phenol Using a Carbon Paste Electrode Modified with Ionic Liquids and Magnetic Core‐shell Fe3O4@SiO2/MWCNT Nanocomposite
Authors: Beitollahi Hadi , Tajik Somayeh , Jahani Shohreh
Published: December 2015

A carbon paste electrode was modified with 2‐(4‐Oxo‐3‐phenyl‐3,4‐dihydroquinazolinyl)‐N′‐phenyl‐hydrazinecarbothioamide, magnetic coreshell Fe3O4@SiO2/MWCNT nanocomposite and ionic liquid (n‐hexyl‐3‐methylimidazolium hexafluoro phosphate). The electro‐oxidation of hydrazine at the surface of the modified electrode was studied using electrochemical approaches. This modified electrode offers a considerable improvement in voltammetric sensitivity toward hydrazine, compared to the bare electrode. Square wave voltammetry (SWV) exhibits a linear dynamic range from 7.0×10−8 to 5.0×10−4 M and a detection limit of 40.0 nM for hydrazine. The diffusion coefficient and kinetic parameters (such as electron transfer coefficient and the heterogeneous rate constant) for hydrazine oxidation were also determined. The prepared modified electrode exhibits a very good resolution between the voltammetric peaks of hydrazine and phenol that makes it suitable for the detection of hydrazine in the presence of phenol in real samples.
Cognitive Function in Adolescent Patients with Anorexia Nervosa and Unipolar Affective Disorders
Authors: Sarrar Lea , Holzhausen Martin , Warschburger Petra , Pfeiffer Ernst , Lehmkuhl Ulrike , Schneider Nora
Published: December 2015

Studies have shown impairments in cognitive function among adult patients with anorexia nervosa (AN) and affective disorders (AD). The association between cognitive dysfunctions, AN and AD as well as the specificity for these psychiatric diagnoses remains unclear. Therefore, we examined cognitive flexibility and processing speed in 47 female adolescent patients with AN, 21 female adolescent patients with unipolar affective disorders and 48 female healthy adolescents. All participants completed a neuropsychological test battery.

There were no significant group differences regarding cognitive function, except for psychomotor processing speed with poorer performance in patients with AN. A further analysis revealed that all groups performed with the normal range, although patients with AN were over represented in the poorest performing quartile.

We found no severe cognitive impairments in either patient group. Nevertheless, belonging to the AN group contributed significantly to poor performances in neuropsychological tasks. Therefore, we conclude that the risk for cognitive impairments is slightly higher for patients with AN. Copyright © 2015 John Wiley & Sons, Ltd and Eating Disorders Association.
Factors contributing to nitrate contamination in a groundwater recharge area of the North China Plain
Authors: Wang Shiqin , Tang Changyuan , Song Xianfang , Yuan Ruiqiang , Han Zhiwei , Pan Yun
Published: December 2015

Nitrate contamination is a common problem in groundwater of the North China Plain (NCP) owing to overuse of fertilizers and discharge of wastewater. Accordingly, it is important to investigate nitrate contamination in recharge areas to understand the fate of nitrate in the plains area. In this study, the spatial and temporal distribution characteristics of nitrate and factors contributing to its sources and transformation in shallow groundwater of the Beiyishui River watershed, NCP, were analysed by a combination of multiple regression and multi‐tracer methods. The nitrate concentration of 79% of the samples exceeded the natural environmental standard of 13.3 mg l−1, while that of 23% of the samples exceeded the World Health Organization (WHO) drinking water standard of 50 mg l−1. Groundwater age estimation of the hill regions based on chlorofluorocarbons (CFCs) revealed a mix of young water from 1982 to 1990 and old, low CFC water. The analysis based on the variations in land use in past years revealed that part of the grassland was converted into woodland between 1980 and 1995; therefore, the land use at the recharge time was used to determine which surface conditions influence groundwater nitrate concentrations. Multiple regression analysis showed that point source pollution contributed to the high concentration of nitrate in the hill region. Fertilizer application associated with land use change from grassland to woodland was also related to the present nitrate concentration. In the plains area, the contribution of fresh water from fault fractures and denitrification led to 31 to 72% and 6 to 51% reductions in nitrate concentrations, respectively. Our results suggested that controlling point source contamination and fertilizer input to hilly regions of the study will prevent groundwater of the plains area from deterioration in future years by mixing fresh water into the aquifers and decreasing denitrification, and therefore nitrate concentrations. Copyright © 2015 John Wiley & Sons, Ltd.
The marine triterpene glycoside frondoside A exhibits activity in vitro and in vivo in prostate cancer
Authors: Dyshlovoy Sergey A. , Menchinskaya Ekaterina S. , Venz Simone , Rast Stefanie , Amann Kerstin , Hauschild Jessica , Otte Katharina , Kalinin Vladimir I. , Silchenko Alexandra S. , Avilov Sergey A. , Alsdorf Winfried , Madanchi Ramin , Bokemeyer Carsten , Schumacher Udo , Walther Reinhard , Aminin Dmitry L. , Fedorov Sergey N. , Shubina Larisa K. , Stonik Valentin A. , Balabanov Stefan , Honecker Friedemann , von Amsberg Gunhild
Published: December 2015

Despite recent advances in the treatment of metastatic castration‐resistant prostate cancer (CRPC), outcome of patients remains poor due to the development of drug resistance. Thus, new drugs are urgently needed. We investigated efficacy, toxicity and mechanism of action of marine triterpene glycoside frondoside A (FrA) using CRPC cell lines in vitro and in vivo. FrA revealed high efficacy in human prostate cancer cells, while non‐malignant cells were less sensitive. Remarkably, proliferation and colony formation of cells resistant to enzalutamide and abiraterone (due to the androgen receptor splice variant AR‐V7) were also significantly inhibited by FrA. The marine compound caused cell type specific cell cycle arrest and induction of caspase‐dependent or ‐independent apoptosis. Up‐regulation or induction of several pro‐apoptotic proteins (Bax, Bad, PTEN), cleavage of PARP and caspase‐3 and down‐regulation of anti‐apoptotic proteins (survivin and Bcl‐2) were detected in treated cells. Global proteome analysis revealed regulation of proteins involved in formation of metastases, tumor cell invasion, and apoptosis, like keratin 81, CrkII, IL‐1β and cathepsin B. Inhibition of pro‐survival autophagy was observed following FrA exposure. In vivo, FrA inhibited tumor growth of PC‐3 and DU145 cells with a notable reduction of lung metastasis, as well as circulating tumor cells in the peripheral blood. Increased lymphocyte counts of treated animals might indicate an immune modulating effect of FrA. In conclusion, our results suggest that FrA is a promising new drug for the treatment of mCRPC. Induction of apoptosis, inhibition of pro‐survival autophagy, and immune modulatory effects are suspected modes of actions.
A component analysis of toilet‐training procedures recommended for young children
Authors: Greer Brian D. , Neidert Pamela L. , Dozier Claudia L.
Published: December 2015

We evaluated the combined and sequential effects of 3 toilet‐training procedures recommended for use with young children: (a) underwear, (b) a dense sit schedule, and (c) differential reinforcement. A total of 20 children participated. Classroom teachers implemented a toilet‐training package consisting of all 3 procedures with 6 children. Of the 6 children, 2 showed clear and immediate improvements in toileting performance, and 3 showed delayed improvements. Teachers implemented components of the training package sequentially with 12 children. At least 2 of the 4 children who experienced the underwear component after baseline improved. Toileting performance did not improve for any of the 8 children who were initially exposed to either the dense sit schedule or differential reinforcement. When initial training components were ineffective, teachers implemented additional components sequentially until toileting performance improved or all components were implemented. Toileting performance often improved when underwear or differential reinforcement was later added.
Psychological Therapy for At Risk Mental State for Psychosis in a Prison Setting: A Case Study
Authors: Huddy Vyv , Roberts Anna , Jarrett Manulea , Valmaggia Lucia
Published: December 2015

There is a very high prevalence of psychosis in U.K. prisons; moreover, a significant number of prisoners meet risk criteria for psychosis. We provide a report of psychological therapy with a client who met risk criteria for psychosis that took place in a prison setting. We applied a self‐reflectivity framework when formulating the case, which we believe allowed the flexibility required by the presenting problem and, crucially, the demands of the setting. This approach had two key advantages. First, it enabled the therapist to tailor the work according to the level of self‐reflectivity demonstrated by the client. We believe this approach ensured that the client understood the therapist's interventions. Second, it helped prepare, and choose a appropriate point, for a move to more traditional interventions for managing the client's main presenting problem. We believe this work represents progress in working with clients in this complex and demanding setting.