bluuebunny/crossref_metadata_2025 huggingface dataset:
Formation of Hybrid Perovskite Tin Iodide Single Crystals by Top‐Seeded Solution Growth
Authors: Dang Yangyang , Zhou Yian , Liu Xiaolong , Ju Dianxing , Xia Shengqing , Xia Haibing , Tao Xutang
Published: February 2016

Hybrid perovskites have generated a great deal of interest because of their potential in photovoltaic applications. However, the toxicity of lead means that there is interest in finding a nontoxic substitute. Bulk single crystals of both cubic CH3NH3SnI3 and CH(NH2)2SnI3 were obtained by using the top‐seeded solution growth method under an ambient atmosphere. Structural refinement, band gap, thermal properties, and XPS measurements of CH3NH3SnI3 and CH(NH2)2SnI3 single crystals are also reported in detail. These results should pave the way for further applications of CH3NH3SnI3 and CH(NH2)2SnI3.
Organocatalytic, Asymmetric Total Synthesis of (−)‐Haliclonin A
Authors: Guo Lian‐Dong , Huang Xiong‐Zhi , Luo Shi‐Peng , Cao Wen‐Sen , Ruan Yuan‐Ping , Ye Jian‐Liang , Huang Pei‐Qiang
Published: February 2016

The first total synthesis of the alkaloid (−)‐haliclonin A is reported. The asymmetric synthesis relied on a novel organocatalytic asymmetric conjugate addition of nitromethane with 3‐alkenyl cyclohex‐2‐enone to set the stereochemistry of the all‐carbon quaternary stereogenic center. The synthesis also features a Pd‐promoted cyclization to form the 3‐azabicyclo[3,3,1]nonane core, a SmI2‐mediated intermolecular reductive coupling of enone with aldehyde to form the requisite secondary chiral alcohol, ring‐closing alkene and alkyne metathesis reactions to build the two aza‐macrocyclic ring systems, and an unprecedented direct transformation of enol into enone.
Enhanced Electron Transfer Reactivity of a Nonheme Iron(IV)–Imido Complex as Compared to the Iron(IV)‐Oxo Analogue
Authors: Vardhaman Anil Kumar , Lee Yong‐Min , Jung Jieun , Ohkubo Kei , Nam Wonwoo , Fukuzumi Shunichi
Published: February 2016

Reactions of N,N‐dimethylaniline (DMA) with nonheme iron(IV)‐oxo and iron(IV)‐tosylimido complexes occur via different mechanisms, such as an N‐demethylation of DMA by a nonheme iron(IV)‐oxo complex or an electron transfer dimerization of DMA by a nonheme iron(IV)‐tosylimido complex. The change in the reaction mechanism results from the greatly enhanced electron transfer reactivity of the iron(IV)‐tosylimido complex, such as the much more positive one‐electron reduction potential and the smaller reorganization energy during electron transfer, as compared to the electron transfer properties of the corresponding iron(IV)‐oxo complex.
Characterization of the Oxygen Binding Motif in a Ruthenium Water Oxidation Catalyst by Vibrational Spectroscopy
Authors: Duffy Erin M. , Marsh Brett M. , Voss Jonathan M. , Garand Etienne
Published: February 2016

For homogeneous mononuclear ruthenium water oxidation catalysts, the Ru–O2 complex plays a crucial role in the rate determining step of the catalytic cycle, but the exact nature of this complex is unclear. Herein, the infrared spectra of the [Ru(tpy)(bpy)(O2)]2+ complex (tpy=2,2′:6′,2′′‐terpyridine; bpy=2,2′‐bipyridine) are presented. The complex [Ru(tpy)(bpy)(O2)]2+, formed by gas‐phase reaction of [Ru(tpy)(bpy)]2+ with molecular O2, was isolated by using mass spectrometry and was directly probed by cryogenic ion IR predissociation spectroscopy. Well‐resolved spectral features enable a clear identification of the O−O stretch using 18O2 substitution. The band frequency and intensity indicate that the O2 moiety binds to the Ru center in a side‐on, bidentate manner. Comparisons with DFT calculations highlight the shortcomings of the B3LYP functional in properly depicting the Ru–O2 interaction.
Polarized Neutron Diffraction to Probe Local Magnetic Anisotropy of a Low‐Spin Fe(III) Complex
Authors: Ridier Karl , Mondal Abhishake , Boilleau Corentin , Cador Olivier , Gillon Béatrice , Chaboussant Grégory , Le Guennic Boris , Costuas Karine , Lescouëzec Rodrigue
Published: February 2016

We have determined by polarized neutron diffraction (PND) the low‐temperature molecular magnetic susceptibility tensor of the anisotropic low‐spin complex PPh4[FeIII(Tp)(CN)3]⋅H2O. We found the existence of a pronounced molecular easy magnetization axis, almost parallel to the C3 pseudo‐axis of the molecule, which also corresponds to a trigonal elongation direction of the octahedral coordination sphere of the FeIII ion. The PND results are coherent with electron paramagnetic resonance (EPR) spectroscopy, magnetometry, and ab initio investigations. Through this particular example, we demonstrate the capabilities of PND to provide a unique, direct, and straightforward picture of the magnetic anisotropy and susceptibility tensors, offering a clear‐cut way to establish magneto‐structural correlations in paramagnetic molecular complexes.
Bioisosteric Exchange of C‐Chloro and Methyl Substituents: Synthesis and Initial Biological Studies of Atpenin A5 Analogues
Authors: Krautwald Simon , Nilewski Christian , Mori Mihoko , Shiomi Kazuro , Ōmura Satoshi , Carreira Erick M.
Published: February 2016

Asymmetric synthesis and initial biological studies of two analogues of a naturally occurring chlorinated antifungal agent, atpenin A5, are described. These analogues were selected on the basis of Cl→CH3 or H3C→Cl exchanges in the side‐chain of atpenin A5. The interchange of chloro and methyl substituents led to complex II inhibitors with equal IC50 values. This suggests that Cl↔Me bioisosteric exchange can be realized in aliphatic settings.
New heteroleptic palladium(II) dithiocarbamates: synthesis, characterization, packing and anticancer activity against five different cancer cell lines
Authors: Khan Shahan Zeb , Amir Muhammad Kashif , Ullah Imdad , Aamir Asma , Pezzuto John M. , Kondratyuk Tamara , Bélanger‐Gariepy Francine , Ali Akbar , Khan Sajid , Zia‐ur‐Rehman
Published: February 2016

Two new heteroleptic palladium(II) complexes have been synthesized by reacting equimolar quantities of palladium(II) chloride, sodium 4‐(2‐methoxyphenyl)piperazine‐1‐carbodithioate and diphenyl‐p‐tolylphosphine (1) or tri‐p‐tolylphosphine (2). Complexes 1 and 2 have been characterized using elemental analysis, Fourier transform infrared spectroscopy, multinuclear NMR (1H, 13C and 31P) spectroscopy and single‐crystal X‐ray analysis. The latter technique confirms a pseudo square‐planar geometry in which two adjacent positions are occupied by bidentate dithiocarbamate while chloro and substituted triphenylphosphine are present at the remaining two positions. The anticancer activity of both complexes against five different cancer cell lines (LU – human lung carcinoma, established at UIC, Department of Surgical Oncology; MCF7 – human breast adenocarcinoma, ATCC number HTB‐22™; MDA‐MB‐231 – human breast adenocarcinoma, ATCC number HTB‐26™; Hepa‐1c1c7 – mouse liver hepatoma, ATCC number CRL‐2026™; PC‐3 – human prostate adenocarcinoma, ATCC number CRL‐1435™) was determined by MTT assay, revealing 2 has higher activity than 1. A drug–calf thymus DNA binding study with UV–visible spectroscopy reveals a higher DNA binding affinity of 2 (3.511 × 104 M−1) than 1 (4.213 × 103 M−1). Density functional theory studies confirm the relatively more stable nature of 2 than 1. Copyright © 2016 John Wiley & Sons, Ltd.
WASP‐ASSOCIATED FACTORS ACT IN INTERSPECIES COMPETITION DURING MULTIPARASITISM
Authors: Magdaraog Peter M. , Tanaka Toshiharu , Harvey Jeffrey A.
Published: February 2016

Coexistence or displacement of parasitoids in hosts during intrinsic competitive interactions between different parasitoid species (multiparasitism) may depend on their life history traits and behavior. Intense competition for possession of hosts may lead to the elimination of the inferior competitor through physical attack and/or physiological suppression. However, the mechanisms of physiological suppression during multiparasitism remain unclear. Previous work has shown that first instar larvae of the solitary endoparasitoid Meteorus pulchricornis possess well‐developed mandibles that are used to kill competitors. Two gregarious endoparasitoids, Cotesia kariyai and C. rufricus, share host resources especially when the time gap of oviposition is short. Here, we investigated the physiological influence of wasp‐regulatory factors of the three endoparasitoids, M. pulchricornis, C. kariyai, and C. ruficrus, in their common host Mythimna separata. We found that MpVLP alone (or with venom) deleteriously affected the development of the two gregarious species. Similarly, CkPDV plus venom had toxic effect on M. pulchricornis eggs and immature larvae, although they were not harmful to immature stages of C. ruficrus. Cotesia kariyai and C. ruficrus were able to coexist mainly through the expression of regulatory factors and both could successfully emerge from a multiparasitized host. The injection of CkPDV plus venom after oviposition in L5 host larvae facilitated C. ruficrus development and increased the rate of successful parasitism from 9% to 62%. This suggests that the two gregarious parasitoid wasps exhibit strong phylogenetic affinity, favoring their coexistence and success in multiparasitized hosts.
Governance, accountability and the datafication of early years education in England
Authors: Roberts‐Holmes Guy , Bradbury Alice
Published: February 2016

In this paper we attempt to critically ‘make visible the flow and circulation of data’ through analysing the datafication of the early years education sector in England (children aged 2–5). The concept of datafication is used to understand the processes and impacts of burgeoning data‐based governance and accountability regimes. This analysis builds upon early childhood researchers who were influenced by Foucault and others, who have noted the ways in which the surveillance and performative culture of accountability both affirms, legitimates and seduces through discourses of quality while increasingly regulating and governing the early years. Using data from three research sites (a children's centre, a primary school and a combined nursery school and children's centre) as well as an interview with a local authority early years advisor, we examine how comparative data‐based accountability increasingly governed early years teachers' professionalism and pedagogies. We argue that the planned tracking of children's performance from baseline assessment at four years old to eleven years old may further govern and constrain early years professionalism as young children are reconfigured as ‘miniature centres of calculation’.
A reductionist metastasis‐on‐a‐chip platform for in vitro tumor progression modeling and drug screening
Authors: Skardal Aleksander , Devarasetty Mahesh , Forsythe Steven , Atala Anthony , Soker Shay
Published: February 2016

Current animal and 2‐D cell culture models employed in metastasis research and drug discovery remain poor mimics of human cancer physiology. Here we describe a “metastasis‐on‐a‐chip” system allowing real time tracking of fluorescent colon cancer cells migrating from hydrogel‐fabricated gut constructs to downstream liver constructs within a circulatory fluidic device system that responds to environmental manipulation and drug treatment. Devices consist of two chambers in which gut and liver constructs are housed independently, but are connected in series via circulating fluid flow. Constructs were biofabricated with a hyaluronic acid‐based hydrogel system, capable of a variety of customizations, inside of which representative host tissue cells were suspended and metastatic colon carcinoma tumor foci were created. The host tissue of the constructs expressed normal epithelial markers, which the tumor foci failed to express. Instead, tumor regions lost membrane‐bound adhesion markers, and expressed mesenchymal and proliferative markers, suggesting a metastatic phenotype. Metastatic tumor foci grew in size, eventually disseminating from the intestine construct and entering circulation, subsequently reaching in the liver construct, thus mimicking some of the migratory events observed during metastasis. Lastly, we demonstrated the ability to manipulate the system, including chemically modulating the hydrogel system mechanical properties and administering chemotherapeutic agents, and evaluated the effects of these parameters on invasive tumor migration. These results describe the capability of this early stage metastasis‐on‐a‐chip system to model several important characteristics of human metastasis, thereby demonstrating the potential of the platform for making meaningful advances in cancer investigation and drug discovery. Biotechnol. Bioeng. 2016;113: 2020–2032. © 2016 Wiley Periodicals, Inc.
Designed DNA Surfaces for in Vitro Modulation of Natural Killer Cells
Authors: Garrecht Ruben , Meyer Rebecca , Duppach Janine , Reipschläger Simone , Watzl Carsten , Niemeyer Christof M.
Published: February 2016

Natural killer (NK) cells are at the junction of the innate and the adaptive immune response and play a very important role in host defense against viral infections and cancer. They have numerous cell surface receptors that activate or inhibit various intracellular signaling cascades that are then integrated to determine the functional activity of these cells. Here we present a surface‐based approach that aims to tackle the largely unknown molecular mechanisms of signal integration. We use DNA microarrays containing capture oligonucleotides for the DNA‐directed immobilization (DDI) of oligonucleotide‐tagged αCD16 antibodies as ligands for NK cells. We demonstrate that the resulting surfaces can be gradually tuned in terms of ligand density to trigger the activation of living NK cells, as evidenced by degranulation, the release of cytokines, and intracellular Ca2+ flux, measured at the level of single cells.
Adipose stem cells differentiated chondrocytes regenerate damaged cartilage in rat model of osteoarthritis
Authors: Latief Noreen , Raza Fahad Ali , Bhatti Fazal‐Ur‐Rehman , Tarar Moazzam Nazir , Khan Shaheen N. , Riazuddin Sheikh
Published: February 2016

Transplantation of mesenchymal stem cells (MSCs) or autologous chondrocytes has been shown to repair damages to articular cartilage due to osteoarthritis (OA). However, survival of transplanted cells is considerably reduced in the osteoarthritic environment and it affects successful outcome of the transplantation of the cells. Differentiated chrondroytes derived from adipose stem cells have been proposed as an alternative source and our study investigated this possibility in rats. We investigated the regenerative potential of ADSCs and DCs in osteoarthritic environment in the repair of cartilage in rats. We found that ADSCs maintained fibroblast morphology in vitro and also expressed CD90 and CD29. Furthermore, ADSCs differentiated into chondrocytes, accompanied by increased level of proteoglycans and expression of chondrocytes specific genes, such as, Acan, and Col2a1. Histological examination of transplanted knee joints showed regeneration of cartilage tissue compared to control OA knee joints. Increase in gene expression for Acan, Col2a1 with concomitant decrease in the expression of Col1a1 suggested formation of hyaline like cartilage. A significant increase in differentiation index was observed in DCs and ADSCs transplanted knee joints (P = 0.0110 vs. P = 0.0429) when compared to that in OA control knee joints. Furthermore, transplanted DCs showed increased proliferation along with reduction in apoptosis as compared to untreated control. In conclusion, DCs showed better survival and regeneration potential as compared with ADSCs in rat model of OA and thus may serve a better option for regeneration of osteoarthritic cartilage.
Short‐Mesochannel SBA‐15‐Supported Chiral 9‐Amino Epicinchonine for Asymmetric Transfer Hydrogenation of Aromatic Ketones
Authors: Lou Lan‐Lan , Li Shanshan , Du Huanling , Zhang Jiong , Yu Wenjun , Yu Kai , Liu Shuangxi
Published: February 2016

A short‐mesochannel SBA‐15 material functionalized with propylthiol groups was prepared by co‐condensation and applied to the immobilization of chiral 9‐amino epicinchonine. After complexing with [Ir(cod)Cl]2 (cod=1,5‐cyclooctadiene), these mesoporous materials were evaluated as catalysts for the asymmetric transfer hydrogenation of aromatic ketones. Higher enantioselectivities and comparable, or even higher, catalytic activities were achieved compared with the free catalyst. Both the short mesochannel and co‐condensation approach for short‐mesochannel SBA‐15 materials functionalized with propylthiol groups, [SSBA‐SH(x)] materials were demonstrated to contribute to the excellent catalytic performance. In addition, the catalyst SSBA‐AEC(5)/Ir (AEC=9‐amino epicinchonine), with low 3‐mercaptopropyltrimethoxysilane (MPTMS) content, showed the best catalytic performance; a high enantiomeric excess of 84 % (homogeneous ee=60 %) along with a conversion of 97 % was achieved within 1 h for asymmetric transfer hydrogenation of acetophenone. Moreover, these immobilized catalysts showed high stability during the reaction and could be recovered for reuse.
In Situ FTIR Spectroscopy: Probing the Electrochemical Interface during the Oxygen Reduction Reaction on a Commercial Platinum High‐Surface‐Area Catalyst
Authors: Nesselberger Markus , Arenz Matthias
Published: February 2016

In situ observation of anion adsorption on industrial high‐surface‐area catalysts is used for the first time under oxygen reduction reaction (ORR) conditions with a defined mass transport. For this purpose, a specially fabricated electrode is used for which the catalyst layer is spray‐coated on top of a structured Au contact layer and applied to our recently developed in situ attenuated total reflectance FTIR wall‐jet electrode. The designed interface allows us to track anion adsorption and measure the reaction rate simultaneously under mass controlled conditions. The observed absorption bands are caused by anion interaction with the active phase and also the carbon support. If we analyze the absorption band intensity of adsorbed anions as a function of the oxygen reduction reaction rate, the band intensity decreases with the onset of the ORR. This shows that ORR inhibition is a complex interplay between site blocking caused by anion adsorption and oxide formation.
On the Importance of Regulating Hydroxyl Coverage on the Basal Plane of Graphene Oxide for Supercapacitors
Authors: Pak Alexander J. , Hwang Gyeong S.
Published: February 2016

Reduced graphene oxide (rGO) has been explored as an alternative to graphene as an electrode material for use in supercapacitors, which thus enables highly scalable solution‐based processing. To understand the performance of rGO electrodes in supercapacitors, we theoretically investigate model systems by considering OH‐functionalized graphene immersed in 1‐ethyl‐3‐methylimidazolium bis(fluorosulfonyl)imide (EMIM/FSI) ionic liquid. Our specific interest is to understand the influence of varying the hydroxyl content (or O/C ratio) on both the quantum (CQ) and electric double‐layer (CD) capacitances. Ultimately, the total interfacial capacitance is found to be sensitive to O/C, but is optimized when the suppression of CD is most effectively mitigated by the enhancement in CQ. Our findings clearly demonstrate that the use of GO materials has the potential to enhance supercapacitor performance significantly but will require careful control of both the concentration and composition of oxygen functional groups along the basal surface.
Aggregation‐Induced Emission Active Probe for Light‐Up Detection of Anionic Surfactants and Wash‐Free Bacterial Imaging
Authors: Gao Meng , Wang Luochao , Chen Junjian , Li Shiwu , Lu Guanhai , Wang Lin , Wang Yingjun , Ren Li , Qin Anjun , Tang Ben Zhong
Published: February 2016

Anionic surfactants are widely used in daily life and industries, but their residues can cause serious damage to the environment. The current detection methods for anionic surfactants suffer from various limitations and a new detection strategy is highly desirable. Based on 2‐(2‐hydroxyphenyl)benzothiazole fluorogen with aggregation‐induced emission characteristics, we have developed a fluorescent probe HBT‐C18 for selective and sensitive detection of anionic surfactants. By in situ formation of catanionic aggregates or micelles with anionic surfactants, the emission intensity of the HBT‐C18 probe can increase with increasing keto/enol emission ratio through restriction of intramolecular motion and excited‐state intramolecular proton‐transfer mechanisms. The probe can also be used for wash‐free imaging of bacteria enveloped by a negatively charged outer membrane. The results of this study provide a new strategy for sensitive detection of anionic surfactants and wash‐free bacterial imaging.
Helical Oligoenes: Conformations, Bond Alternation, and Competing Through‐Bond and Through‐Space Transmission
Authors: Tsuji Yuta , Hoffmann Roald
Published: February 2016

There is a consensus that long‐range electron transfer/transport occurs by a through‐bond rather than through‐space mechanism. In helical all‐Z, all‐s‐cis oligoenes, one can set up an interesting competition in the medium‐separation regime between a closer (in distance) through‐space path and a more distant through‐bond one. Although such oligoene conformations/isomers are unstable (by around 4 kcal mol−1 per double bond relative to all‐E, all‐s‐trans isomers), recent synthetic efforts on truncated helicenes and oligothiophenes have provided related molecules. On the way to transmission calculations with electrodes attached to the termini of helical oligoenes, we uncover an interesting conformational ambiguity in all‐Z, all‐s‐cis oligoenes, the existence of a broad conformational minimum for helical compression, with hints of end‐to‐end frontier‐orbital‐caused stabilization. There is relationship between helical oligoene structures and the corresponding substructure of a helicene, but there are also significant differences in the number of olefin subunits per helix turn. In Hückel transport calculations, the role of TB or TS mechanisms is obscured to an extent by variations in bond alternation and dihedral angle along the oligomer chain. However, the operation of a dominant through bond mechanism emerges clearly in local transmission plots. In moving the electrodes to carbon position related by quantum interference, it is possible to uncover a through space mechanism.
Reactivity, Selectivity, and Reaction Mechanisms of Aminoguanidine, Hydralazine, Pyridoxamine, and Carnosine as Sequestering Agents of Reactive Carbonyl Species: A Comparative Study
Authors: Colzani Mara , De Maddis Danilo , Casali Gaia , Carini Marina , Vistoli Giulio , Aldini Giancarlo
Published: February 2016

Reactive carbonyl species (RCS) are endogenous or exogenous byproducts involved in the pathogenic mechanisms of different oxidative‐based disorders. Detoxification of RCS by carbonyl quenchers is a promising therapeutic strategy. Among the most studied quenchers are aminoguanidine, hydralazine, pyridoxamine, and carnosine; their quenching activity towards four RCS (4‐hydroxy‐trans‐2‐nonenal, methylglyoxal, glyoxal, and malondialdehyde) was herein analyzed and compared. Their ability to prevent protein carbonylation was evaluated in vitro by using an innovative method based on high‐resolution mass spectrometry (HRMS). The reactivity of the compounds was RCS dependent: carnosine efficiently quenched 4‐hydroxy‐trans‐2‐nonenal, pyridoxamine was particularly active towards malondialdehyde, aminoguanidine was active towards methylglyoxal and glyoxal, and hydralazine efficiently quenched all RCS. Reaction products were generated in vitro and were characterized by HRMS. Molecular modeling studies revealed that the reactivity was controlled by specific stereoelectronic parameters that could be used for the rational design of improved carbonyl quenchers.
Convenient, Reliable, Bias‐Free Dynamic Patterning of Multiple Types of Cells into Precisely Defined Micropatterns for Co‐Culture Study
Authors: Dai Wen , Li Wanbo , Ren Kangning , Wu Hongkai
Published: February 2016

We present a simple and flexible mechanical approach for 2D micropatterning of multiple cell lines without surface modification. The principle is that during initial attachment cells only stick to unoccupied areas; we create such areas to selectively seed a subsequent cell line by using a stamp to erase previously attached cells at designed areas. By repeating this process, multiple types of cells were patterned on a single substrate. This strategy minimizes the disturbance to cell health, which might be a concern in printing‐based patterning. Micropatterns of cells with resolution of ≈50 μm, and a co‐culture of three cell types were easily achieved and studied. This method was found universal to at least MSC, HeLa, HepG2 and NIH 3T3. We also measured the invasion and cell growth under the co‐culture of HeLa, MSC and HepG2. This method is useful for studying cell–cell interaction in high‐throughput, free of the potential bias caused by selective surface modification in some previous methods.
High‐Pressure Raman and Calorimetry Studies of Vanadium(III) Alkyl Hydrides for Kubas‐Type Hydrogen Storage
Authors: Morris Leah , Trudeau Michel L. , Reed Daniel , Book David , Antonelli David M.
Published: February 2016

The front cover artwork is provided by David Antonelli′s materials chemistry group at the University of South Wales. The image shows the binding of H2 via the Kubas interaction on amorphous vanadium hydride frameworks. The material stores 5.4 wt % H2 reversibly, and surprisingly the calorimetry measurements shown below the central image demonstrate that the overall process is thermodynamically neutral. Read the full text of the Full Paper at 10.1002/cphc.201501093
A true single‐phase clock dual‐modulus prescaler with enhanced robustness against leakage currents
Authors: Jia Song , Wang Ziyi , Yan Shilin , Wang Yuan
Published: February 2016

A new leakage‐tolerant true single‐phase clock dual‐modulus prescaler based on a stage‐merged scheme is presented. Leakage‐restricting transistors are used to reduce the leakage currents at critical nodes, and leakage‐related malfunctions are eliminated at minimal cost in terms of speed, power, and area overheads. An HSPICE simulation in a 40‐nm process shows that the proposed divide‐by‐2/3 divider can effectively enhance robustness against leakage currents to extend the low frequency limit of the circuit over wide temperature and threshold voltage ranges. Additionally, the proposed design shows speed and power performance that is comparable with the performance levels of referenced designs. Copyright © 2016 John Wiley & Sons, Ltd.
Circulating fibroblast growth factor‐23 plasma levels predict adverse cardiovascular outcomes in patients with diabetes mellitus with coronary artery disease
Authors: Tuñón José , Fernández‐Fernández Beatriz , Carda Rocío , Pello Ana M. , Cristóbal Carmen , Tarín Nieves , Aceña Álvaro , González‐Casaus María Luisa , Huelmos Ana , Alonso Joaquín , Lorenzo Óscar , González‐Parra Emilio , Hernández‐González Ignacio , Mahíllo‐Fernández Ignacio , López‐Bescós Lorenzo , Egido Jesús
Published: February 2016

Background

Abnormalities of fibroblast growth factor‐23 (FGF‐23) plasma levels predict adverse outcomes in patients with coronary artery disease. However, FGF‐23 has a different behaviour in the presence of type 2 diabetes mellitus (T2D). We explored whether the presence of T2D affects the predictive power of FGF‐23.

Methods

In 704 patients with stable coronary artery disease, FGF‐23, calcidiol, parathormone (PTH) and phosphate plasma levels were prospectively assessed. The primary outcome was the development of acute ischemic events (acute coronary syndrome, stroke or transient ischemic attack), heart failure or death.

Results

One hundred seventy‐three (24.6%) patients had T2D, without differences in age, sex or estimated glomerular filtration rate as compared with non‐diabetic patients. Serum PTH was lower and phosphate higher in T2D than in non‐diabetic patients, without differences in FGF‐23 or calcidiol levels.

During follow‐up (2.15 ± 0.99 years), 26 (15.2%) T2D and 51 (9.6%) non‐diabetic patients developed the outcome (p = 0.048). T2D patients who developed the outcome had higher FGF‐23 [112.0 (59.9, 167.6) vs 68.9 (54.2, 93.0) RU/mL; p = 0.002], PTH [71.3 (47.3, 106.6) vs 51.9 (40.8, 66.2) pg/mL; p = 0.004) and phosphate (3.53 ± 0.71 vs 3.25 ± 0.50 mg/dL; p = 0.017) levels than T2D subjects who remained stable. These differences were not significant in non‐diabetic patients.

By multivariable Cox proportional hazard model, FGF‐23 predicted independently the outcome in T2D patients [hazard ratio = 1.277; 95% CI (1.132, 1.442)] but not in those without T2D.

Conclusions

FGF‐23 plasma levels predict adverse cardiovascular outcomes in coronary artery disease patients who have T2D but not in those without T2D. This finding should be confirmed in larger studies. Copyright © 2016 John Wiley & Sons, Ltd.
Prediabetes and diabetes among HIV‐infected adults in Cameroon
Authors: Rhee John Y. , Bahtila Tumi Divine , Palmer Dennis , Tih Pius Muffih , Aberg Judith A. , LeRoith Derek , Jao Jennifer
Published: February 2016

Background

Human immunodeficiency virus (HIV) and certain antiretrovirals are associated with diabetes. Few studies have examined the prevalence of and factors associated with diabetes among HIV‐infected individuals on combination antiretroviral therapy (cART) in sub‐Saharan Africa; some report prevalence estimates between 3.5–26.5% for diabetes in Cameroon and 20.2–43.5% for prediabetes in sub‐Saharan Africa.

Methods

In a cross‐sectional study, HIV‐infected individuals (16–65 years old) were screened for diabetes using haemoglobin A1c (HbA1c). We further categorized HbA1C as normoglycemia (HbA1c < 5.7%), prediabetes (HbA1c 5.7–6.4%) or diabetes (HbA1c  ≥ 6.5%). Dysglycemia was defined as HbA1c ≥ 5.7%. Logistic regression modelling was used to assess factors associated with having dysglycemia.

Results

Of 500 participants, 363 (72.6%) were female. Median age was 42.5 years [interquartile range (IQR): 36.5–49.5]. Nineteen patients (3.8%) had diabetes and 170 patients (34%) were classified as having prediabetes. One hundred nine (22%) had a CD4+ count <200 cells/mm3, and 464 (93%) had received >28 days of ART at time of screening. Median abdominal circumference for women was 79.5 cm (IQR: 75.5–85.3) and for men, 86.5 cm (IQR: 81.7–90.5). Adjusting for age, sex, socio‐economic status, CD4 cell count, being on cART >28 days, body mass index, hypertension, history of hypertension, abdominal circumference and duration of HIV infection, larger abdominal circumference was associated with higher prevalence of prediabetes or diabetes (adjusted odds ratio = 1.07, 95% confidence interval: 1.03–1.11), while being on cART (adjusted odds ratio = 0.46, confidence interval: 0.22–0.99) was associated with lower prevalence.

Conclusions

There was a high prevalence of dysglycemia among Cameroonian HIV‐infected adults. Larger abdominal circumference was associated with higher prevalence, while cART was associated with lower prevalence. Copyright © 2016 John Wiley & Sons, Ltd.
Selective association of electrocardiographic abnormalities with insulin sensitivity and beta‐cell function in type 2 diabetes mellitus: a cross‐sectional analysis
Authors: Bhatt Anish B. , Mulvey Claire K. , Qasim Atif N. , Nair Jayamohan V. , Rickels Michael R. , Prenner Stuart B. , Iqbal Nayyar , Reilly Muredach P.
Published: February 2016

Background

We investigated the association of electrocardiographic (ECG) abnormalities with markers of insulin resistance and pancreatic beta‐cell dysfunction in a cross‐sectional study of type 2 diabetes patients.

Methods

Electrocardiographic criteria were evaluated in the Penn Diabetes Heart Study participants (n = 1671; 64% male; 61% Caucasian), including a sub‐sample (n = 710) that underwent oral glucose tolerance testing. The Matsuda Insulin Sensitivity Index and homeostasis model assessment of insulin resistance (HOMA‐IR) estimated insulin sensitivity; Insulinogenic Index and homeostasis model assessment of beta‐cell function assessed beta‐cell function. Multivariable regression modelling was used to analyse associations of ECG changes with these indices.

Results

In unadjusted analyses, subjects in the highest quartile of Matsuda index had the lowest prevalence of Q‐waves (6.3% versus 15.3%, p = 0.005). In adjusted models, an inverse association was seen between Q‐waves and log Matsuda index [one standard deviation increase; OR = 0.59 (95% CI 0.43‐0.87 p = 0.001)]. In the full Penn Diabetes Heart Study, there was a direct association between Q‐waves and HOMA‐IR [one standard deviation increase; OR = 1.43 (95% CI 1.13–1.81, p = 0.003)]. In adjusted models, left ventricular hypertrophy also was inversely associated with Matsuda index and directly with HOMA‐IR. Higher Insulinogenic Index scores were associated with a lower prevalence of nonspecific ST changes [OR = 0.78 (95% CI 0.62–0.98, p = 0.032)].

Conclusions

In type 2 diabetic patients, both oral glucose tolerance testing‐derived and HOMA‐derived measures of insulin resistance were associated with pathologic Q‐waves and left ventricular hypertrophy on ECGs. Copyright © 2016 John Wiley & Sons, Ltd.
Costs of resistance and infection by a generalist pathogen
Authors: Dallas Tad , Holtackers Mathieu , Drake John M.
Published: February 2016

Pathogen infection is typically costly to hosts, resulting in reduced fitness. However, pathogen exposure may also come at a cost even if the host does not become infected. These fitness reductions, referred to as “resistance costs”, are inducible physiological costs expressed as a result of a trade‐off between resistance to a pathogen and aspects of host fitness (e.g., reproduction). Here, we examine resistance and infection costs of a generalist fungal pathogen (Metschnikowia bicuspidata) capable of infecting a number of host species. Costs were quantified as reductions in host lifespan, total reproduction, and mean clutch size as a function of pathogen exposure (resistance cost) or infection (infection cost). We provide empirical support for infection costs and modest support for resistance costs for fiveDaphniahost species. Specifically, only one host species examined incurred a significant cost of resistance. This species was the least susceptible to infection, suggesting the possibility that host susceptibility to infection is associated with the detectability and size of resistance cost. Host age at the time of pathogen exposure did not influence the magnitude of resistance or infection cost. Lastly, resistant hosts had fitness values intermediate between unexposed control hosts and infected hosts. Although not statistically significant, this could suggest that pathogen exposure does come at some marginal cost. Taken together, our findings suggest that infection is costly, resistance costs may simply be difficult to detect, and the magnitude of resistance cost may vary among host species as a result of host life history or susceptibility.
Scorched mussels (Brachidontesspp., Bivalvia: Mytilidae) from the tropical and warm‐temperate southwestern Atlantic: the role of the Amazon River in their speciation
Authors: Trovant Berenice , Basso Néstor G. , Orensanz José María , Lessa Enrique P. , Dincao Fernando , Ruzzante Daniel E.
Published: February 2016

Antitropicality is a distribution pattern where closely related taxa are separated by an intertropical latitudinal gap. Two potential examples includeBrachidontes darwinianus(south eastern Brazil to Uruguay), considered by some authors as a synonym ofB. exustus(Gulf of Mexico and the Caribbean), andB. solisianus, distributed along the Brazilian coast with dubious records north of the intertropical zone. Using two nuclear (18S and 28SrDNA) and one mitochondrial gene (mtDNA COI), we aimed to elucidate the phylogeographic and phylogenetic relationships among the scorched mussels present in the warm‐temperate region of the southwest Atlantic. We evaluated a divergence process mediated by the tropical zone over alternative phylogeographic hypotheses.Brachidontes solisianuswas closely related toB. exustus I,a species with which it exhibits an antitropical distribution. Their divergence time was approximately 2.6 Ma, consistent with the intensification of Amazon River flow.Brachidontes darwinianus,an estuarine species is shown here not to be related to thisB. exustuscomplex. We suspect ancestral forms may have dispersed from the Caribbean to the Atlantic coast via the Trans‐Amazonian seaway (Miocene). The third species, B rodrigueziiis presumed to have a long history in the region with related fossil forms going back to the Miocene. Although scorched mussels are very similar in appearance, their evolutionary histories are very different, involving major historical contingencies as the formation of the Amazon River, the Panama Isthmus, and the last marine transgression.
Method of Shortening Settling Time Using Final State Control for High‐Precision Stage with Decouplable Structure of Fine and Coarse Parts
Authors: YAZAKI YUMA , FUJIMOTO HIROSHI , HORI YOICHI , SAKATA KOICHI , HARA ATSUSHI , SAIKI KAZUAKI
Published: February 2016

High‐precision stages require high‐speed and high‐precision control to improve their production throughput and quality. However, their motion speed and accuracy are expected to reach a limit in the near future if the conventional high‐precision stage structure is used. Therefore, the authors designed and fabricated a “catapult stage,” which has a structure that can be decoupled into a fine stage and coarse stage. The catapult stage is different from conventional dual stages in which the fine stage is disturbed by the coarse stage because they contact each other. This paper proposes a novel control system design for the catapult stage and a control method that shortens the settling time by using final state control (FSC). So far, FSC has mainly been used for applications such as hard disk drives, for which the initial states are zero. However, it is important to consider the initial states for the catapult stage because the initial position, velocity, and acceleration of the catapult stage are not equal to zero. Simulations and experiments were performed to demonstrate the effectiveness of the proposed methods.
Mesenteric lymph nodes contribute to proinflammatory Th17‐cell generation during inflammation of the small intestine in mice
Authors: Kawabe Takeshi , Suzuki Nobu , Yamaki Satoshi , Sun Shu‐lan , Asao Atsuko , Okuyama Yuko , So Takanori , Iwakura Yoichiro , Ishii Naoto
Published: February 2016

T cells of the small intestine, including Th17 cells, are critically involved in host protection from microbial infection, and also contribute to the pathogenesis of small bowel inflammatory disorders. Accumulating evidence suggests that mesenteric lymph nodes (MLNs) play important roles in gut‐tropic T‐cell generation, although it is still unclear if MLNs are involved in the pathogenesis of small intestine inflammation. To address this issue, we analyzed the roles of both MLNs and Peyer's patches (PPs) by evaluating MLN‐ or PP‐deficient mice in an experimental model of small intestine inflammation, induced by CD3‐specific mAb injection. Interestingly, MLNs, but not PPs, were essential for the pathogenesis of intestinal inflammation, in particular the accumulation and infiltration of CD4+ T‐cell populations, including Th17 cells, from the blood. In addition, CD4+ T‐cell accumulation was dependent on the function of the α4β7 integrin. Furthermore, MLN removal led to a significantly reduced number of peripheral α4β7+ CD4+ effector memory T cells under normal conditions, suggesting that MLNs may play a role in maintaining the number of gut‐tropic CD4+ effector memory T cells circulating in the blood. Taken together, the present study highlights the important role of MLNs in contributing to the pathogenesis of small intestine inflammation.
Manganese–Salicyloximate Clusters Starting from [MnII(hfacac)2]: From Mn4 to Mn12
Authors: Escuer Albert , Cordero Beatriz , Font‐Bardia Mercè , Teat Simon J. , Roubeau Olivier
Published: February 2016

The systematic exploration of the reactivity of [Mn(hfacac)2] with R‐salicyloximes (R‐saloxH2: R = H, Me, Et) yielded a family of clusters with nuclearities ranging from Mn4 to Mn12. The compounds with formula [Mn6(O)2(salox)6(CF3COO)2(EtOH)4] (1) and [Mn12(salox)12(O)4(N3)4(H2O)2(MeOH)6] (4) show two or four linked {Mn(µ3‐O)(salox)3}+ triangular subunits. Magnetic measurements revealed spin ground states of S = 4 for 1 and S = 8 for 4, as well as single‐molecule magnet responses and magnetic hysteresis above 2 K. The cubic [Mn4(Mesalox)4(MesaloxH)4] (2), the hexanuclear [Mn6(Etsalox)6(O)2(MeO)4(MeOH)2] (3) and the octanuclear [Mn8(Mesalox)6(O)2(N3)6(MeOH)8] (5) are polymorphs of previously reported systems. Small structural changes allows an S = 11 ground state for 3.
Tridentate Lewis Acids: Boron‐, Silicon‐ and Gallium‐Functionalised Tris(dimethylsilyl)methanes
Authors: Weisheim Eugen , Schwartzen Anna , Kuhlmann Lisa , Neumann Beate , Stammler Hans‐Georg , Mitzel Norbert W.
Published: February 2016

Flexible tridentate Lewis acids based on new trisilylmethane scaffolds with three ethynyl groups {Me3SiC[Si(Me)2C≡C–H]3} and three vinyl groups {Me3SiC[Si(Me)2CH=CH2]3}, respectively, have been synthesised and functionalised by metallation with gallium organyls to yield Me3SiC[Si(Me)2C≡C–GaR2]3 (R = Me, Et). Hydrometallation of the trisilylmethane frameworks with HB(C6F5)2 and various chlorosilanes afforded flexible poly‐Lewis acids equipped with B(C6F5)2, SiCl3, SiMeCl2 and SiMe2Cl substituents. The reaction of these silicon‐containing tridentate Lewis acids with SbF3 led to fluorine‐substituted poly‐Lewis acids of the type Me3SiC[Si(Me)2CH2CH2SiMe3–nFn]3 (n = 1–3). All the compounds were characterised by multinuclear NMR spectroscopy, mass spectrometry, elemental analyses and some by X‐ray diffraction.
Long‐Lived, Emissive Excited States in Direct and Amide‐Linked Thienyl‐Substituted RuII Complexes
Authors: Majewski Marek B. , Smith Jeremy G. , Wolf Michael O. , Patrick Brian O.
Published: February 2016

The excited state behavior of a new series of homoleptic and heteroleptic RuII complexes bearing thienyl groups appended to a 2,2′‐bipyridine chelating ligand via direct, secondary and tertiary amide linkages is examined. The results of nanosecond transient absorption spectroscopy, emission lifetime measurements and bimolecular quenching experiments are correlated to determine that although the amide linkage does not act as a conjugated bridge to the peripheral substituents, it does not preclude possible electron transfer processes. Complexes bearing directly bound thienyl and bithienyl substituents exhibit long excited state and emission lifetimes (τem = 2 and 15 µs), with high emission quantum yields in solution (Φ = 0.35) and slow rates of non‐radiative decay.
Ruthenium‐ and Rhodium‐Catalyzed Strain‐Driven Cleavage and Reconstruction of the C–C Bond
Authors: Kondo Teruyuki
Published: February 2016

The synthesis of new functional organic molecules that cannot be obtained by a simple combination of conventional synthetic methods is a challenging subject in organic, organometallic, and industrial chemistry as well as in atom‐efficient and environmental organic synthesis. Among the various possibilities that have been considered, the catalytic cleavage and reconstruction of the C–C bond has opened the door to a new branch of synthetic organic chemistry. This microreview summarizes progress on the ruthenium‐ and rhodium‐catalyzed strain‐driven cleavage of the C–C bond, the methods of which were mostly developed by the author. The direct oxidative addition of 2,5‐norbornadienes, cyclopropenones, cyclobutenones, and cyclobutenediones, and to catalytically active metal species followed by the construction of the C–C bond has been used for the preparation of new organic molecules.
Regioselective Chlorination of Quinoline N‐Oxides and Isoquinoline N‐Oxides Using PPh3/Cl3CCN
Authors: Qiao Kai , Wan Li , Sun Xiaoning , Zhang Kai , Zhu Ning , Li Xin , Guo Kai
Published: February 2016

A novel method for the regioselective C2‐chlorination of heterocyclic N‐oxides has been developed. PPh3/Cl3CCN were used as chlorinating reagents and the desired N‐heterocyclic chlorides were obtained smoothly in satisfactory yields. The reactions proceeded in a highly efficient and selective manner across a broad range of substrates demonstrating excellent functional group tolerance. In addition, this chlorination reaction can be used for the modification of N‐heterocyclic scaffolds of appealing ligands and pharmaceuticals.
Assessing atmospheric concentration of polychlorinated biphenyls by evergreen Rhododendron maximum next to a contaminated stream
Authors: Dang Viet D. , Walters David M. , Lee Cindy M.
Published: February 2016

Conifers are often used as an air passive sampler, but few studies have focused on the implication of broadleaf evergreens to monitor atmospheric semivolatile organic compounds such as polychlorinated biphenyls (PCBs). In the present study, the authors used Rhododendron maximum (rhododendron) growing next to a contaminated stream to assess atmospheric PCB concentrations. The present study area was located in a rural setting and approximately 2 km downstream of a former capacitor plant. Leaves from the same mature shrubs were collected in late fall 2010 and winter and spring 2011. Polychlorinated biphenyls were detected in the collected leaves, suggesting that rhododendron can be used as air passive samplers in rural areas where active sampling is impractical. Estimated ΣPCB (47 congeners) concentrations in the atmosphere decreased from fall 2010 to spring 2011 with concentration means at 3990 pg m−3, 2850 pg m−3, and 931 pg m−3 in fall 2010, winter 2011, and spring 2011, respectively. These results indicate that the atmospheric concentrations at this location continue to be high despite termination of active discharge from the former industrial source. Leaves had a consistent pattern of high concentrations of tetra-CBs and penta-CBs similar to the congener distribution in polyethylene passive samplers deployed in the water column, suggesting that volatilized PCBs from the stream were the primary source of contaminants in rhododendron leaves. Environ Toxicol Chem 2016;35:2192–2198. © 2016 SETAC
Telecommunication integration in e‐healthcare: technologies, applications and challenges
Authors: Majedi Nick , Naeem Muhammad , Anpalagan Alagan
Published: February 2016

The technological advancements in sensing, signal processing, computing and communication have had great influence in different aspect of our lives. One of the fields that benefit from these technologies is health care. Trustworthiness of sensors, electronic devices, networks and wireless communications have matured enough to replace traditional legacy systems. However, there remains unexplored aspects of e‐healthcare especially considering the challenges in service provisioning, integration and resource optimization. Pervasive and continuous health monitoring is an important service, and it specifically provides the elderly and chronically ill patients with continuous and seamless health monitoring, benefiting both of them and the caretakers. In this survey article, we review and discuss different elements of e‐healthcare, introduce wireless transmission technologies that are used in e‐healthcare, present the quality of service (QoS) requirements and discuss the potential challenges as in security and privacy of data, power allocation, scheduling, meeting the QoS needs and confronting the electromagnetic interference. Some of the future research directions in healthcare areas are also discussed. Copyright © 2016 John Wiley & Sons, Ltd.