bluuebunny/crossref_metadata_2025 huggingface dataset:
Solid‐State 17O NMR Reveals Hydrogen‐Bonding Energetics: Not All Low‐Barrier Hydrogen Bonds Are Strong
Authors: Lu Jiasheng , Hung Ivan , Brinkmann Andreas , Gan Zhehong , Kong Xianqi , Wu Gang
Published: February 2017

While NMR and IR spectroscopic signatures and structural characteristics of low‐barrier hydrogen bond (LBHB) formation are well documented in the literature, direct measurement of the LBHB energy is difficult. Here, we show that solid‐state 17O NMR spectroscopy can provide unique information about the energy required to break a LBHB. Our solid‐state 17O NMR data show that the HB enthalpy of the O⋅⋅⋅H⋅⋅⋅N LBHB formed in crystalline nicotinic acid is only 7.7±0.5 kcal mol−1, suggesting that not all LBHBs are particularly strong.
An Irreversible Inhibitor of HSP72 that Unexpectedly Targets Lysine‐56
Authors: Pettinger Jonathan , Le Bihan Yann‐Vaï , Widya Marcella , van Montfort Rob L. M. , Jones Keith , Cheeseman Matthew D.
Published: February 2017

The stress‐inducible molecular chaperone, HSP72, is an important therapeutic target in oncology, but inhibiting this protein with small molecules has proven particularly challenging. Validating HSP72 inhibitors in cells is difficult owing to competition with the high affinity and abundance of its endogenous nucleotide substrates. We hypothesized this could be overcome using a cysteine‐targeted irreversible inhibitor. Using rational design, we adapted a validated 8‐N‐benzyladenosine ligand for covalent bond formation and confirmed targeted irreversible inhibition. However, no cysteine in the protein was modified; instead, we demonstrate that lysine‐56 is the key nucleophilic residue. Targeting this lysine could lead to a new design paradigm for HSP72 chemical probes and drugs.
Water‐soluble Schiff base Cu(II) and Zn(II) complexes: Synthesis, DNA targeting ability and chemotherapeutic potential of Cu(II) complex for hepatocellular carcinoma –in vitroandin vivoapproach
Authors: Pravin Narayanaperumal , Kumaravel Ganesan , Senthilkumar Raju , Raman Natarajan
Published: February 2017

Reliable compounds with low toxicity are tempting potential chemotherapeutics. With an aim of achieving less toxic but more potent metallodrugs, four new‐generation hydrophilic Cu(II) and Zn(II) complexes with DNA‐targeting properties were synthesized and characterized using various physicochemical data. The excellent DNA binding and cleavage results confirmed the mode of binding of DNA with the complexes and their ability to denature it. The profoundin vitrocytotoxicity exhibited by complex3against a panel of cell lines (HeLa, MCF‐7 and HepG‐2) along with NHDF (normal human dermal fibroblasts) with distinct activity towards HepG‐2 and low toxicity to NHDF promptedin vivostudies of induced hepatocellular carcinoma‐affected Swiss albino rats. On evaluating various serum hepatic, biological and histopathological parameters, complex3showed excellent activity in restoring the damaged liver to normal. As a means of identifying the pathway of DNA damage, flow cytometric evaluation of cell cycle analysis was performed, which revealed S phase arrest‐induced apoptosis in HepG‐2 cells by complex3, making it a cell cycle‐specific drug.
Local mechanical behavior mapping of a biopolymer blend using nanoindentation, finite element computation, and simplex optimization strategy
Authors: Guessasma Sofiane , Zhang Weihong , Zhu Jihong
Published: February 2017

In this study, we suggest a simple scheme to derive interfacial behavior using combination of nanoindentation and finite element computation. The starting point is the experimental generation of a rectangular grid composed of 32 indentations to measure the exact variation of stiffness across the interface of a bio‐based composite. A finite element simulation of nanoindentation is implemented based on elasto‐plastic material model. An optimization strategy is used to identify the behavior of all phases by matching predicted results to observed mechanical response. Results show that extent of interphase layer has a typical dimension of 8.0 ± 4.9 µm. The optimization strategy based on simplex proves to be efficient to derive the elasto‐plastic behavior of the blend across the interface with a residual value of less than 30 µN. The identification procedure demonstrates that the extent of the interfacial region depends on the measured physical quantity. The contrast across the interface for both Young's and the tangent moduli appear to be more effective than the contrast given by the yield stress. Identified Young's moduli for zein, starch, and interfacial zone are 4.78 ± 0.27, 4.13 ± 0.19, and 3.91 ± 0.17 GPa. Plasticity parameter represented by tangent modulus varies in the same order as 1238 ± 120, 847 ± 108, and 976 ± 94 MPa, respectively. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44891.
Polymers of norbornenyl‐4‐phenol: Dissolution rate characteristics, positive tone photo‐patterning, and polymer properties
Authors: Evans Paul J. , Brick Chad M. , Bell Andrew , Kandanarachchi Pramod , Thoresen Jennifer , Rhodes Larry F. , Onishi Osamu , Ikeda Haruo , Benedikt George M. , Koronich Elaine
Published: February 2017

Vinyl addition norbornene polymers with phenol pendent groups are obtained by methanolysis of the 4‐acetoxyphenyl norbornene polymer. Thin films of this polymer blended with additives such as norbornene polymers with hexafluoroalcohol pendent groups and diazonaphthoquinone compounds result in linear dissolution in tetramethylammonium hydroxide developer. Good resolution, positive tone patterns are obtained from image‐wise exposure of thin films of blends of the diazonaphthoquinone additives with both phenol pendent norbornene homopolymer and with norbornene copolymers with both phenol and hexafluoroalcohol pendent groups. Properties such as transparency, dielectric constant, chemical, and thermal resistance were determined for cured copolymer compositions containing an epoxy crosslinker. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44952.
Preparation and characterization of binary blends composed of poly(dioctylfluorene‐alt‐hexylsulfonylthiophene) and nonconjugated polymers
Authors: Chiu Hsien‐Tang , Yu Chin‐Yang , Wang Yu‐Hsiang , Wu Szu‐Han
Published: February 2017

The solutions and the thin films of poly[9,9‐dioctyl‐2,7‐fluorene‐alt‐2,5–(3‐hexyl‐sulfonylthiophene)] (PFSO2T) and its binary blends with other nonconjugated polymers such as poly(methyl methacrylate) (PMMA), polycarbonate (PC), and ethylene vinyl acetate copolymer (EVA) can be prepared by different concentrations from a polymer solution. Binary polymer blends can increase the absorbance and photoluminescence intensities in the solid state due to nonconjugated polymers can act as dispersion agents which can reduce the interchain interaction or the aggregation of the conjugated polymers. Photoluminescence intensity of the thin films of fluorescent polymers blending with ethylene vinyl acetate copolymers exhibited six times higher than that of the neat fluorescent polymers. The PFSO2T/EVA binary blends reveal the least extent of optical degradation of around 20% compared to those binary blends in both absorption and emission intensities after the irradiation under the UV‐light for 20 h. The cross‐sectional morphology of fluorescent polymers blending with ethylene vinyl acetate copolymers reveals little aggregation and better phase separation among the other binary polymer blends. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44969.
The adipokinetic hormone of Mantodea in comparison to other Dictyoptera
Authors: Gäde Gerd , Marco Heather G.
Published: February 2017

Six species of the order Mantodea (praying mantises) are investigated for the presence and sequence of putative adipokinetic hormones (AKHs). The selected species span a wide evolutionary range of various families and subfamilies of the clade Mantodea. The corpora cardiaca of the different species are dissected, methanolic extracts prepared, peptides separated by liquid chromatography, and AKHs detected and sequenced by ion trap mass spectrometry. All six species investigated contain an octapeptide with the primary structure pGlu‐Val‐Asn‐Phe‐Thr‐Pro‐Asn‐Trp amide, which is code‐named Emppe‐AKH and had been found earlier in three other species of Mantodea. Conspecific bioassays with the species Creoboter sp. (family Hymenopodidae) reveal an adipokinetic but not a hypertrehalosemic function of Emppe‐AKH. Comparison with other members of the Dictyoptera (cockroaches, termites) show that Emppe‐AKH is only found in certain termites, which have been recently placed into the Blattaria (cockroaches) as sister group to the family Cryptocercidae. Termites and cockroaches both show biodiversity in the sequence of AKHs, and some cockroach species even contain two AKHs. In contrast, all praying mantises—irrespective of their phylogenetic position—synthesize uniformly only one and the same octapeptide Emppe‐AKH.
Stereoisomerization of Cyclic Silanols
Authors: Endo Hisayuki , Takeda Nobuhiro , Unno Masafumi
Published: February 2017

Stereoisomerization of readily available all‐cis‐1,3,5,7‐tetrahydroxy‐1,3,5,7‐tetraisobutylcyclotetrasiloxane (1 a) was carried out under acidic conditions to afford cis‐trans‐cis (1 b), all‐trans (1 c), and cis‐cis‐trans (1 d) isomers. The compounds in the reaction mixture could be easily separated into 1 a and a mixture of 1 b, 1 c, and 1 d by the treatment with chloroform. Compounds 1 b, 1 c, and 1 d were further separated and isolated, and each structure was identified. The experimental results indicated that the most plausible mechanism is a substitution reaction at the silicon center via a pentacoordinate intermediate without a cyclic siloxane bond cleavage reaction. The obtained isomer 1 a or 1 b further reacted with dichlorodiphenylsilane in the presence of triethylamine to give syn‐type laddersiloxane (2 a) or anti‐type laddersiloxane (2 b), respectively.
Characteristics of wet and dry spells in the West African monsoon system
Authors: Froidurot Stéphanie , Diedhiou Arona
Published: February 2017

Using 17 years (1998–2014) of daily TRMM 3B42 rainfall data, we provide a climatological characterization of wet and dry spells in West Africa, which should serve to assess the ability of climate model to simulate these high impact events. The study focuses on four subregions (Western and Central Sahel, Sudanian zone and Guinea Coast). Defining wet (dry) spells as sequences of consecutive days with precipitation higher (lower) than 1 mm, we describe the space‐time variability of wet and dry spell occurrence. This climatology stresses the influence of the relief on the number and duration of these spells. The spatio‐temporal variability of the wet and dry spells also appears to be closely related to the spatio‐temporal variability of the West African monsoon. The number of wet spells of all durations and of 2–3 day dry spells have similar features with a maximum occurrence during the local rainy seasons and a spatial pattern similar to the mean annual rainfall with a north–south gradient. In contrast, dry spells lasting more than four days show some singularities such as a low occurrence over the Sahelian band or high occurrence along the Guinea Coast mainly from Ivory Coast to Benin. Moreover, the seasonal cycle of these longer dry spells presents higher occurrences at the beginning and the end of the rainy seasons.
Isolation and Quantification of Phenolic Compounds in Acer tegmentosum by High Performance Liquid Chromatography
Authors: Lee JungIn , Hwang In Hyun , Jang Tae Su , Na MinKyun
Published: February 2017

Determination of bioactive chemicals in Acer tegmentosum is essential for its industrial application. Twelve phenolic compounds were isolated from A. tegmentosum. Specific seven compounds in the plant were simultaneously analyzed by high performance liquid chromatography‐UV. The content of bioactive chemicals in the branch extract was determined to be 3.38 mg/g of (−)‐epigallocatechin, 66.95 mg/g of salidroside, 39.61 mg/g of tyrosol, 17.04 mg/g of catechin, 7.39 mg/g of 1,2,4‐tri‐O‐galloyl‐β‐d‐glucose, 8.88 mg/g of 6‐O‐galloylsalidroside, and 4.61 mg/g of scopoletin. The method was validated with linearity (
R
2
> 0.9947), as well as intra‐ and inter‐day precision (0.07–2.77%) and accuracy (>97.0%). This analytical method is expected to be applied for standardization of dietary food containing A. tegmentosum.
CADASIL: Ultrastructural insights into the morphology of granular osmiophilic material
Authors: Lorenzi Teresa , Ragno Michele , Paolinelli Francesca , Castellucci Clara , Scarpelli Marina , Morroni Manrico
Published: February 2017

Introduction

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a hereditary systemic vascular disorder. Granular osmiophilic material (GOM) is its ultrastructural marker. We reviewed tissue biopsies from CADASIL patients to establish whether ultrastructural observations help clarify the pathogenic mechanism of CADASIL. Given the resemblance of the GOM deposits to the immunoglobulin deposits seen in glomerulonephritis and focal segmental glomerulosclerosis (FSGS), their morphologies were investigated and compared.

Methods

Skin, skeletal muscle, kidney, and pericardium tissue biopsies from 13 patients with a clinical and molecular diagnosis of CADASIL, and kidney biopsies from five patients with IgA nephropathy and five patients with primary FSGS were subjected to ultrastructural examination.

Results

In CADASIL patients, several GOM deposits from all sites were partially or totally surrounded by an electron‐lucent halo. The deposits frequently had a more electron‐dense portion with a regular outline on the inner side and a less osmiophilic, looser outer side displaying a less regular profile. The uniformly dense deposits tended to be more osmiophilic if located close to the cell membrane and less osmiophilic if laid farther away from it. The immunoglobulin deposits from the glomerulonephritis and FSGS patients lacked both the granular pattern and the halo.

Conclusions

This study demonstrates that GOM deposits may have a nonuniform morphology and describes in detail an electron‐lucent halo surrounding several of them. It is conceivable that the halo is the morphological evidence and possibly the cause of an aberrant NOTCH3 processing, already suspected to be involved in CADASIL.
Controlling Cellular Uptake and Toxicity of Polyphenylene Dendrimers by Chemical Functionalization
Authors: Hammer Brenton A. G. , Wu Yuzhou , Fischer Stephan , Liu Weina , Weil Tanja , Müllen Klaus
Published: February 2017

Polyphenylene dendrimers (PPDs) represent a unique class of macromolecules based on their monodisperse and shape‐persistent nature. These characteristics have enabled the synthesis of a new genre of “patched” surface dendrimers, where their exterior can be functionalized with a variety of polar and nonpolar substituents to yield lipophilic binding sites in a site‐specific way. Although such materials are capable of complexing biologically relevant molecules, show high cellular uptake in various cell lines, and low to no toxicity, there is minimal understanding of the driving forces to these characteristics. We investigated whether it is the specific chemical functionalities, relative quantities of each moiety, or the “patched” surface patterning on the dendrimers that more significantly influences their behavior in biological media.
Ebastine overdose in a child
Authors: Pecoraro Luca , Paiola Giulia , Pietrobelli Angelo
Published: February 2017

Key Clinical Message

The lack of side effects after acute ingestion of a high dose of ebastine in our child aging 44 months suggests an overall safety profile of ebastine; it could suggest less time of hospitalization for children who are subjected to this event.
Looking at the Future of Chemical Production through the European Roadmap on Science and Technology of Catalysis the EU Effort for a Long‐term Vision
Authors: Perathoner Siglinda , Gross Silvia , Hensen Emiel J. M. , Wessel Helge , Chraye Hélène , Centi Gabriele
Published: February 2017

This Essay presents in short the initiative of the European Commission to strengthen the activities in the area of catalysis, a key technology for a sustainable future. In particular, this Essay discusses the thematic European Cluster on Catalysis and its main output: The European Roadmap on Science and Technology of Catalysis. Between the main drivers for the sustainable future of chemical and energy vectors, production of the following aspects have been identified: 1) the change in the energy–chemistry nexus, and the need to move to a new sustainable energy scenario and of enabling long‐distance (world scale) trading of renewable energy, 2) the change to a new vision for refineries, bio‐refineries, and bio‐factories, 3) methanol, as key chemical at the crossover of new energy–chemistry nexus, 4) the new possibilities by exploiting shale‐gas, and bio‐gas‐based chemistry, and 5) solar‐driven chemistry. To address this changing scenario, the Roadmap has identified a series of grand‐challenges for catalysis, discussed in terms of the strategic research agenda and implementation plans: 1) catalysis to address the evolving energy and chemical scenario, 2) catalysis for a cleaner and sustainable future, and 3) addressing catalysis complexity—the latter being divided in three sub‐topics (advanced design of novel catalysts, understanding catalysts from a molecular to a material scale, and expanding catalysis concepts).
Heterogeneous Ketone Hydrodeoxygenation for the Production of Fuels and Feedstocks from Biomass
Authors: Jenkins Rhodri W. , Moore Cameron M. , Semelsberger Troy A. , Sutton Andrew D.
Published: February 2017

In this work, we describe a simple, heterogeneous catalytic system for the hydrodeoxygenation (HDO) of 5‐nonanone and 2,5‐hexanedione, which we use as model compounds for more complex biomass‐derived molecules. We present the stepwise reduction of ketones by using supported metal and solid acid catalysts to identify the intermediates en route to hydrocarbons. Although monoketone HDO can be achieved rapidly using moderate conditions (Ni/SiO2.Al2O3, HZSM‐5, 200 °C, 1.38 MPa H2, 1 h), quantitative γ‐polyketone HDO requires higher pressures and longer reaction times (Pd/Al2O3, HZSM‐5, 2.76 MPa H2, 5 h), although these are more facile conditions than have been reported previously for γ‐polyketone HDO. Stepwise HDO of the γ‐polyketone shows the reaction pathway occurs through ring‐closure to a saturated tetrahydrofuran species intermediate, which requires increased H2 pressure to ring‐open and subsequently to fully HDO. This work allows for further understanding of bio‐derived molecule defunctionalization mechanisms, and ultimately aids in the promotion of biomass as a feedstock for fuels and chemicals.
Excellent Cycling Stability and Superior Rate Capability of Na3V2(PO4)3 Cathodes Enabled by Nitrogen‐Doped Carbon Interpenetration for Sodium‐Ion Batteries
Authors: Zhang Huang , Hasa Ivana , Qin Bingsheng , Diemant Thomas , Buchholz Daniel , Behm R. Jürgen , Passerini Stefano
Published: February 2017

Polyanionic Na3V2(PO4)3 is considered as a promising cathode material for sodium‐ion batteries; however, it is limited by its poor electronic conductivity resulting in inferior rate capability and cycling stability. Herein, the rational design and synthesis of Na3V2(PO4)3 (NVP) particles embedded in various N‐doped carbon matrices, that is, nitrogen‐doped pyrolytic carbon (N−C), carbon nanotubes (N‐CNT), graphene nanosheets (N‐rGO), and Ketjen black nanospheres (N‐KB), are reported together with the structural investigation and electrochemical performance. It is evidenced that the N‐doped carbon coating efficiently improves the rate capability and cyclability with minor polarization of NVP materials as a result of enhanced electronic/ionic conductivities and facilitated charge transfer at the electrode−electrolyte interface. Particularly, the NVP nanograins dispersed in the N‐doped carbon nanotube matrix exhibit the best rate and cycling performance. When cycled at rates from 0.1 to 20 C, the discharge capacity decays only slightly from 114 to 100 mAh g−1, offering outstanding high power capacity retention (88 %). Moreover, the material retains excellent capacity (92 %) upon long‐term cycling (3000 cycles) at extremely high rate of 50 C.
Double Sequential Encrypted Targeting Sequence: A New Concept for Bone Cancer Treatment
Authors: Villaverde Gonzalo , Nairi Valentina , Baeza Alejandro , Vallet‐Regí María
Published: February 2017

The selective transportation of therapeutic agents to tumoral cells is usually achieved by their conjugation with targeting moieties able to recognize these cells. Unfortunately, simple and static targeting systems usually show a lack in selectivity. Herein, a double sequential encrypted targeting system is proposed as a stimuli‐responsive targeting analogue for selectivity enhancement. The system is able to recognize diseased bone tissue in the first place, and once there, a hidden secondary targeting group is activated by the presence of an enzyme overproduced in the malignant tissue (cathepsin K), thereby triggering the recognition of diseased cells. Transporting the cell targeting agent in a hidden conformation that contains a high selective tissular primary targeting, could avoid not only its binding to similar cell receptors but also the apparition of the binding‐site barrier effect, which can enhance the penetration of the therapeutic agent within the affected zone. This strategy could be applied not only to conjugate drugs but also to drug‐loaded nanocarriers to improve the efficiency for bone cancer treatments.
From Bola‐Surfactant Templated Bimetal Phosphites to the Design of Crystalline Inorganic Mesoporous Frameworks
Authors: Huang Hui‐Lin , Huang Wen‐Yen , Wang Sue‐Lein
Published: February 2017

Reproducing inorganic modules in situ for pore augmentation of pure inorganic frameworks is challenging but can be a key to rational synthesis. After the first success of using monoamines of varied lengths as a template in producing a set of building blocks that led to a series of growing channels up to a 72‐membered ring (72R), research continued into those building blocks to seek any new topologies from them. In this study, another type of template is reported that can control the same building blocks to repeatedly form in situ. By using long linear‐chain bola‐type surfactants, two new bimetal phosphites, a monoclinic phase exhibiting remarkable quasi‐channels of 1.15 nm and an orthorhombic phase with 28R channels of 1.06 nm have been created. By taking them as the first members, two series of novel topologies can be devised, each having a general formula to predict the size and channel wall compositions.
σ‐Hole and π‐Hole Synthon Mimicry in Third‐Generation Crystal Engineering: Design of Elastic Crystals
Authors: Saha Subhankar , Desiraju Gautam R.
Published: February 2017

Designing elastic crystals is a difficult task and is of relevance in potential applications from materials to biology. Here, multi‐step crystal engineering based on σ‐hole and π‐hole synthon mimicry is performed to obtain binary organic molecular crystals with a high degree of flexibility. A structural model is proposed based only on σ‐hole‐oriented type‐II halogen bonds with their characteristic orthogonal geometry. These σ‐hole contacts are then partly replaced by chemically and geometrically similar π‐hole synthons to obtain new crystals in the second step. In the final step, all the σ‐hole interactions are replaced with π‐hole interactions and elastic crystals of non‐halogenated compounds are obtained. All the crystals obtained according to our protocols are found to be elastic. When crystals that do not conform to the desired structure type appeared, they were found to be brittle. This underlines the role of orthogonal‐type interactions, whether they are of the σ‐hole or π‐hole type, in achieving elasticity. This is the first report in which π‐hole interactions are used for property engineering. This example may illustrate a new generation of crystal engineering in which a particular property is associated more with topological rather than chemical attributes, although the significance of the latter cannot be completely excluded.
A tree‐parenchyma coupled model for lung ventilation simulation
Authors: Pozin Nicolas , Montesantos Spyridon , Katz Ira , Pichelin Marine , Vignon‐Clementel Irene , Grandmont Céline
Published: February 2017

In this article, we develop a lung ventilation model. The parenchyma is described as an elastic homogenized media. It is irrigated by a space‐filling dyadic resistive pipe network, which represents the tracheobronchial tree. In this model, the tree and the parenchyma are strongly coupled. The tree induces an extra viscous term in the system constitutive relation, which leads, in the finite element framework, to a full matrix. We consider an efficient algorithm that takes advantage of the tree structure to enable a fast matrix‐vector product computation. This framework can be used to model both free and mechanically induced respiration, in health and disease. Patient‐specific lung geometries acquired from computed tomography scans are considered. Realistic Dirichlet boundary conditions can be deduced from surface registration on computed tomography images. The model is compared to a more classical exit compartment approach. Results illustrate the coupling between the tree and the parenchyma, at global and regional levels, and how conditions for the purely 0D model can be inferred. Different types of boundary conditions are tested, including a nonlinear Robin model of the surrounding lung structures.
Clopidogrel–Paclitaxel Drug–Drug Interaction: A Pharmacoepidemiologic Study
Authors: Agergaard K , Mau‐Sørensen M , Stage TB , Jørgensen TL , Hassel RE , Steffensen KD , Pedersen JW , Milo MLH , Poulsen SH , Pottegård A , Hallas J , Brøsen K , Bergmann TK
Published: February 2017

Paclitaxel is mainly eliminated by CYP2C8 in the liver. CYP2C8 is strongly inhibited by the clopidogrel metabolite acyl‐β‐D‐glucuronide. To determine if this interaction has clinical relevance, we identified 48 patients treated with clopidogrel and paclitaxel using databases and a prescription register. Peripheral sensory neuropathy was retrospectively evaluated from medical charts and compared to that of 88 age‐ and sex‐matched controls treated with paclitaxel and low‐dose aspirin. By a cumulative dose of 1,500 mg paclitaxel, 35% of the patients had developed severe neuropathy. The overall hazard ratio between clopidogrel use and severe paclitaxel neuropathy was 1.7 (95% confidence interval, 0.9–3.0). Among those receiving a high‐dose paclitaxel regimen, the hazard ratio was 2.3 (95% confidence interval, 1.1–4.5). Our study indicates that clopidogrel is associated with a clinically relevant increased risk of neuropathy in patients treated with high‐dose paclitaxel.
One‐Pot Process for Hydrodeoxygenation of Lignin to Alkanes Using Ru‐Based Bimetallic and Bifunctional Catalysts Supported on Zeolite Y
Authors: Wang Hongliang , Ruan Hao , Feng Maoqi , Qin Yuling , Job Heather , Luo Langli , Wang Chongmin , Engelhard Mark H. , Kuhn Erik , Chen Xiaowen , Tucker Melvin P. , Yang Bin
Published: February 2017

The synthesis of high‐efficiency and low‐cost catalysts for hydrodeoxygenation (HDO) of waste lignin to advanced biofuels is crucial for enhancing current biorefinery processes. Inexpensive transition metals, including Fe, Ni, Cu, and Zn, were severally co‐loaded with Ru on HY zeolite to form bimetallic and bifunctional catalysts. These catalysts were subsequently tested for HDO conversion of softwood lignin and several lignin model compounds. Results indicated that the inexpensive earth‐abundant metals could modulate the hydrogenolysis activity of Ru and decrease the yield of low‐molecular‐weight gaseous products. Among these catalysts, Ru‐Cu/HY showed the best HDO performance, affording the highest selectivity to hydrocarbon products. The improved catalytic performance of Ru‐Cu/HY was probably a result of the following three factors: (1) high total and strong acid sites, (2) good dispersion of metal species and limited segregation, and (3) high adsorption capacity for polar fractions, including hydroxyl groups and ether bonds. Moreover, all bifunctional catalysts proved to be superior over the combination catalysts of Ru/Al2O3 and HY zeolite.
Levenberg‐Marquardt optimization method for coverage and connectivity control in backbone‐based wireless networks
Authors: Khan Khalid , Lobiyal D. K.
Published: February 2017

One of the main challenge in designing wireless networks is to ensure optimal coverage and connectivity, which can be achieved by optimally repositioning nodes in backbone network such that the total energy requirement is minimized. Therefore, an efficient optimization algorithm that converges at faster rate while minimizing the cost function (total power) is required. In this paper, we propose the use of Levenberg‐Marquardt optimization algorithm to achieve assured coverage and connectivity control in backbone‐based wireless networks. The Levenberg‐Marquardt method combines the advantages of Cauchy steepest descent method and Newton‐Raphson method and is expected to achieve faster convergence rate irrespective of initial conditions, which is the main motivation of this study. It relies on that when current solution is far from the optimal solution, then steepest descent method will be used, and as current solution approaches to optimal solution, then gradually switched to Newton‐Raphson method to find the optimal solution. Extensive simulations using MATLABR2020a has been performed to demonstrate the effectiveness of proposed method by measuring its performance in the number of iterations, elapsed time, and power requirement to maintain proper coverage and connectivity. The performance is compared with Cauchy steepest descent method as well as Newton‐Raphson method.
Self‐selection bias in eating disorders outcomes research: Does treatment response of underweight research participants and non‐participants differ?
Authors: Schreyer Colleen C. , Redgrave Graham W. , Hansen Jennifer L. , Guarda Angela S.
Published: February 2017

Observational treatment studies provide a valuable alternative to RCTs but are often criticized due to potential self‐selection biases. Studies comparing those who do and do not participate in research on eating disorder treatment are scarce, but necessary to evaluate the impact of self‐selection bias on outcomes. All consecutive underweight adult first admissions (N = 392) to an integrated inpatient (IP)‐partial hospital (PH) behavioral specialty program were invited to participate in a longitudinal study of eating disorder treatment. Demographic and hospital course data were collected on participants (n = 234) and non‐participants (n = 158). Participants and non‐participants had similar BMI at admission, lengths of stay, and weight gain rates. Participants were less likely than non‐participants to end treatment prematurely from IP and were discharged at a higher BMI; the effect size was small. Few differences in hospital course were observed between participants and non‐participants. Although participants were more likely to transition to PH and were discharged at a higher BMI, completion of step‐down to PH within this integrated IP‐PH program rather than research participation status at admission was a better indicator of discharge BMI, which remains the strongest predictor of long‐term weight‐maintenance in eating disorders.
Species distribution modeling and molecular markers suggest longitudinal range shifts and cryptic northern refugia of the typical calcareous grassland species Hippocrepis comosa (horseshoe vetch)
Authors: Leipold Martin , Tausch Simone , Poschlod Peter , Reisch Christoph
Published: February 2017

Calcareous grasslands belong to the most diverse, endangered habitats in Europe, but there is still insufficient information about the origin of the plant species related to these grasslands. In order to illuminate this question, we chose for our study the representative grassland species Hippocrepis comosa (Horseshoe vetch). Based on species distribution modeling and molecular markers, we identified the glacial refugia and the postglacial migration routes of the species to Central Europe. We clearly demonstrate that H. comosa followed a latitudinal and due to its oceanity also a longitudinal gradient during the last glacial maximum (LGM), restricting the species to southern refugia situated on the Peninsulas of Iberia, the Balkans, and Italy during the last glaciation. However, we also found evidence for cryptic northern refugia in the UK, the Alps, and Central Germany. Both species distribution modeling and molecular markers underline that refugia of temperate, oceanic species such as H. comosa must not be exclusively located in southern but also in western of parts of Europe. The analysis showed a distinct separation of the southern refugia into a western cluster embracing Iberia and an eastern group including the Balkans and Italy, which determined the postglacial recolonization of Central Europe. At the end of the LGM, H. comosa seems to have expanded from the Iberian refugium, to Central and Northern Europe, including the UK, Belgium, and Germany.
Bacterial cell‐to‐cell signaling promotes the evolution of resistance to parasitic bacteriophages
Authors: Moreau Pierre , Diggle Stephen P. , Friman Ville‐Petri
Published: February 2017

The evolution of host–parasite interactions could be affected by intraspecies variation between different host and parasite genotypes. Here we studied how bacterial host cell‐to‐cell signaling affects the interaction with parasites using two bacteria‐specific viruses (bacteriophages) and the host bacterium Pseudomonas aeruginosa that communicates by secreting and responding to quorum sensing (QS) signal molecules. We found that a QS‐signaling proficient strain was able to evolve higher levels of resistance to phages during a short‐term selection experiment. This was unlikely driven by demographic effects (mutation supply and encounter rates), as nonsignaling strains reached higher population densities in the absence of phages in our selective environment. Instead, the evolved nonsignaling strains suffered relatively higher growth reduction in the absence of the phage, which could have constrained the phage resistance evolution. Complementation experiments with synthetic signal molecules showed that the Pseudomonas quinolone signal (PQS) improved the growth of nonsignaling bacteria in the presence of a phage, while the activation of las and rhl quorum sensing systems had no effect. Together, these results suggest that QS‐signaling can promote the evolution of phage resistance and that the loss of QS‐signaling could be costly in the presence of phages. Phage–bacteria interactions could therefore indirectly shape the evolution of intraspecies social interactions and PQS‐mediated virulence in P. aeruginosa.
Role of the Trichlorostannyl Ligand in Tin–Ruthenium Arene Complexes: Experimental and Computational Studies
Authors: Novák Miroslav , Bouška Marek , Dostál Libor , Lutter Michael , Jurkschat Klaus , Turek Jan , De Proft Frank , Růžičková Zdeňka , Jambor Roman
Published: February 2017

A set of neutral and ionic ruthenium arene trichlorostannyl complexes are reported herein. The tin(II) compounds L1SnCl {1; L1 = [2‐(CH2NEt2)‐4,6‐(tBu)2C6H2]–} and [L2SnCl][SnCl3] {2; L2 = 2,6‐[(CH3)C=N(C6H3‐2,6‐iPr2)2]C5H3N} showed a rather different reactivity towards the ruthenium complex [(η6‐cymene)RuCl]2(η‐Cl)2. As a consequence, the neutral complex [Ru(η6‐cymene)(L1SnCl)Cl2] (4) and the ionic compound [L2SnCl][Ru(η6‐cymene)(SnCl3)2Cl] (8) were isolated. The insertion reaction of 4 with SnCl2 provided the neutral trimetallic ruthenium complex [Ru(η6‐cymene)(L1SnCl)(SnCl3)Cl] (6). Analogous ruthenium complexes [Ru(η6‐cymene)(L3PPh2)Cl2] (5) and [Ru(η6‐cymene)(L3PPh2)(SnCl3)Cl] (7) containing the phosphane ligand L3PPh2 {3; L3 = [2,6‐iPr2‐(C6H3)NH]–} were also prepared to evaluate the donor–acceptor strength of the tin(II)‐ and phosphorus‐containing ligands. The structural characterization and DFT calculations of the above‐mentioned complexes suggest a strong influence of the [SnCl3]– moiety on the Ru–E interaction (E = Sn, P). The influence of the trichlorostannyl ligand on the Ru–E interaction in the complexes 4–7 was further evaluated by means of a distortion/interaction analysis.
Assessment of the toxic effect of pesticides on honey bee drone fertility using laboratory and semifield approaches: A case study of fipronil
Authors: Kairo Guillaume , Poquet Yannick , Haji Haïthem , Tchamitchian Sylvie , Cousin Marianne , Bonnet Marc , Pelissier Michel , Kretzschmar André , Belzunces Luc P. , Brunet Jean-Luc
Published: February 2017

Concern about the reproductive toxicity of plant protection products in honey bee reproducers is increasing. Because the reproductive capacity of honey bees is not currently considered during the risk assessment procedure performed during plant protection product registration, it is important to provide methods to assess such potential impairments. To achieve this aim, we used 2 different approaches that involved semifield and laboratory conditions to study the impact of fipronil on drone fertility. For each approach, the drones were reared for 20 d, from emergence to sexual maturity, and exposed to fipronil via a contaminated sugar solution. In both groups, the effects of fipronil were determined by studying life traits and fertility indicators. The results showed that the survival and maturity rates of the drones were better under laboratory conditions than under semifield conditions. Moreover, the drones reared under laboratory conditions produced more seminal fluid. Although these differences could be explained by environmental factors that may vary under semifield conditions, it was found that regardless of the approach used, fipronil did not affect survival rates, maturity rates, or semen volumes, whereas it did affect fertility by inducing a decrease in spermatozoa quantity that was associated with an increase in spermatozoa mortality. These results confirm that fipronil affects drone fertility and support the relevance of each approach for assessing the potential reproductive toxicity of plant protection products in honey bees. Environ Toxicol Chem 2017;36:2345–2351. © 2017 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC.
Predictive meta-regressions relating mercury tissue concentrations of freshwater piscivorous mammals
Authors: Eccles Kristin M. , Thomas Philippe J. , Chan Hing Man
Published: February 2017

Mercury (Hg) is a pollutant of global concern. Sentinel species such as river otter (Lontra canadensis) and mink (Neovison vison) are often used to monitor environmental concentrations in freshwater ecosystems. Tissue total Hg (THg) concentrations are frequently used as biomarkers of exposure. However, there is no comprehensive model relating Hg tissue concentrations in different tissues, making interstudy comparisons challenging. Our objective was to establish conversion factors relating fur, brain, liver, kidney, and muscle THg concentrations using mean concentrations and standard errors reported in the literature. We used data from more than 6000 samples, pooled across 16 studies and 96 sampling sites in North America and Europe. Sixteen regressions were derived for the river otter and mink models, which were statistically significant at a 95% confidence interval and yielded high explained variances. The models were validated using an external data set of individually measured THg tissue concentrations. The validated conversions were used to evaluate the current fur Hg screening guidelines of 20 µg/g and 30 µg/g. At both of these fur concentrations, brain concentrations are of concern for altering brain neurochemistry. We suggest a more conservative fur Hg screening guideline of 15 µg/g to protect sensitive furbearers. The conversion factors can be used to predict internal organ THg concentrations from fur measurements, eliminating the need for invasive tissue sampling. Environ Toxicol Chem 2017;36:2377–2384. © 2017 SETAC

Abstract

Relational paths between different tissue compartments in river otter and mink.
Synthesis of new functionalized organophosphorus derivatives of methane‐ and 4‐substituted benzenesulfonic acids with P–C–N moieties
Authors: Prishchenko Andrey A. , Livantsov Mikhail V. , Novikova Olga P. , Livantsova Ludmila I. , Petrosyan Valery S.
Published: February 2017

The convenient methods of syntheses of new organophosphorus methane‐ and 4‐substituted benzenenesulfonylamides from the trivalent organophosphorus acid esters and reactive N‐chloromethyl N‐methyl methanesulfonylamide, phosphorylated methylamines with NH‐ and NSi moieties and methane‐ and 4‐substituted benzenesulfonyl chlorides were developed. The new types of functionalized organophosphorus derivatives of methane‐ and 4‐substituted benzenesulfonic acids with P–C–N moieties were afforded in good yields.
Human butyrylcholinesterase efficacy against nerve agent exposure
Authors: Reed Beth A. , Sabourin Carol L. , Lenz David E.
Published: February 2017

Acetylcholinesterase is vital for normal operation of many processes in the body. Following exposure to organophosphorus (OP) nerve agents, death can ensue without immediate medical intervention. Current therapies mitigate the cholinergic crisis caused by nerve agents but do not fully prevent long‐term health concerns, for example, brain damage following seizures. Human butyrylcholinesterase (HuBChE) is a stoichiometric bioscavenger being investigated as an antidote for OP nerve agent poisoning. HuBChE sequesters OP nerve agent in the bloodstream preventing the nerve agent from reaching critical target organ systems. HuBChE was effective when used as both a pre‐treatment and as a post‐exposure therapy. HuBChE has potential for use in both military settings and to protect civilian first responders in situations where nerve agent usage is suspected. We reviewed various animal models studies evaluating the efficacy of HuBChE against nerve agent exposure, pursuant to its submission for approval under the FDA Animal Rule.
Protective effect of hydroxytyrosol in arsenic‐induced mitochondrial dysfunction in rat brain
Authors: Soni Manisha , Prakash Chandra , Sehwag Sfurti , Kumar Vijay
Published: February 2017

The present study was planned to investigate the protective effect of hydroxytyrosol (HT) against arsenic (As)‐induced mitochondrial dysfunction in rat brain. Rats exposed to sodium arsenite (25 ppm for 8 weeks) showed decreased mitochondrial complexes (I, II, IV) activities, mitochondrial superoxide dismutase (MnSOD), and catalase activities in brain mitochondria. As‐treated rats showed reduced mRNA expression of complex I (ND‐1, ND‐2), IV (COX‐1, COX‐4) subunits, and uncoupling protein‐2 (UCP‐2). In addition to this, As exposure downregulated the protein expression of MnSOD. Administration of HT with As restored the enzymatic activities of mitochondrial complexes, MnSOD and catalase, increased the mRNA levels of complexes subunits and UCP‐2 as well as proteins level of MnSOD. These results suggest that HT efficiently restores mitochondrial dysfunction in As neurotoxicity and might be used as potential mitoprotective agent in future.
Detection of volume alterations in hippocampal subfields of rats under chronic unpredictable mild stress using 7T MRI: A follow‐up study
Authors: Li Yuefeng , Zhu Xiaolan , Ju Shenghong , Yan Jinchuan , Wang Dongqing , Zhu Yan , Zang Fengchao
Published: February 2017

Purpose

To determine hippocampal subfields volume loss in depression, which was simulated by a rat chronic unpredictable mild stress (CUMS) model. As different cellular and molecular characteristics in hippocampal subfields, these subfields are regarded as differentially vulnerable to processes associated with stress.

Materials and Methods

Twenty male Wistar rats were exposed to various stressors until the model was successfully established. The effects of physical exercise on recovery of hippocampal volume in depressed rats were simulated using the wheel running test (WRT). These rats hippocampal volumes were dynamically measured using T2‐weighted images (T2WIs) at 7T structural magnetic resonance imaging (MRI).

Results

After 4 weeks of CUMS (CUMS‐4W), the behavioral tests showed that the rat model of depression was successfully established (P < 0.001). In this process, the bilateral CA1 volume was significantly atrophic after 2 weeks of CUMS (CUMS‐2W) compared with controls (left: 21.09 ± 2.31 vs. 26.16 ± 3.83 mm3, P < 0.001; right: 21.05 ± 2.36 vs. 26.12 ± 3.78 mm3, P < 0.001), whereas the other subfields did not show a similar change (all P > 0.05). The volume of CA3, dentate gyrus (DG), and subiculum displayed atrophy after CUMS‐4W (CA3: left:12.23 ± 1.10 mm3, right: 12.20 ± 1.14 mm3; DG: left:8.16 ± 0.58 mm3, right: 8.18 ± 0.92 mm3; subiculum: left: 4.30 ± 0.52 mm3, right: 4.29 ± 0.44 mm3; all P < 0.05). The rats' (CUMS‐4W) hippocampal DG volume was restored (left: 10.67 ± 1.60 mm3, right: 10.71 ± 1.58 mm3), and the depression‐like behaviors of these rats improved after WRT‐4W (P < 0.05).

Conclusion

In general, volume loss was demonstrated in various rat hippocampal subfields during the development and recovery from depression, which were detected by ultrahigh‐field MRI.

Level of Evidence: 3

Technical Efficacy: Stage 3

J. Magn. Reson. Imaging 2017;46:1456–1463.
Image‐based background phase error correction in 4D flow MRI revisited
Authors: Busch Julia , Giese Daniel , Kozerke Sebastian
Published: February 2017

Purpose

To correct background phase errors in phase‐contrast magnetic resonance imaging (MRI), image‐based correction by referencing through stationary tissue is widely used. The aim of the present study was a detailed assessment of background phase errors in 4D Flow MRI and limitations of image‐based correction.

Materials and Methods

In a phantom study, 4D Flow MRI data were acquired for typical settings on two clinical 3T MR systems. Background errors were analyzed with respect to their spatial order and minimum requirements regarding the signal‐to‐noise ratio (SNR) and the amount of stationary tissue for image‐based correction were assessed. For in vivo evaluation, data of the aorta were acquired on one 3T MR system in five healthy subjects including subsequent scans on the stationary phantom as reference.

Results

Background errors were found to exhibit spatial variation of first‐ to third‐order. For correction, a minimum SNR of 20 was needed to achieve an error of less than 0.4% of the encoding velocity. The minimum amount of stationary tissue was strongly dependent on the spatial order requiring at least 25%, 60%, and 75% of stationary tissue for first‐, second‐, and third‐order correction. In vivo evaluation showed that with 35–41% of stationary tissue available only first‐order correction yielded a significant reduction (P < 0.01).

Conclusion

Background phase errors can range from first to third spatial order in 4D Flow MRI requiring correction with appropriate polynomials. At the same time, the limited amount of stationary tissue available in vivo limits image‐based background phase correction to first spatial order.

Level of Evidence: 1

Technical Efficacy: Stage 1

J. Magn. Reson. Imaging 2017;46:1516–1525.