bluuebunny/crossref_metadata_2025 huggingface dataset:
Elution profiles of lanthanides with α‐hydroxyisobutyric acid by ion exchange chromatography using fine resin
Authors: Trikha Rahul , Sharma Bal Krishan , Sabharwal Kanwal Nain , Prabhu Krishan
Published: September 2015

Experiments were carried out using a strong acid cation exchange resin with a particle size of 75–150 μm, termed as “fine resin” in hydrogen ion form for the elution of individual lanthanides Sm, Eu, Gd, Tb, and Dy that are produced as fission products in the spent nuclear fuel and generated in the effluent during reprocessing of spent nuclear fuel. Batch experiments were carried out to study the effect of concentration of nitric acid on distribution coefficient. The distribution coefficient values for these individual lanthanides were determined in nitric acid medium in the concentration range of 0.01–4.0 N. Uptake of each individual lanthanide by resin was increased with increased nitric acid concentration from 0.01 to 0.5 N and remained similar from 0.5 to 1.0 N and decreased thereafter up to 4.0 N. Column experiments were also carried out using the same resin to study the parameters like pH of the eluent, flow rate, and resin bed height under isocratic elution conditions for eluting lanthanide elements using α‐hydroxyisobutyric acid as eluent. The results of this study have indicated the possibility for the elution of individual lanthanides.
Visible Light Induced Emulsion Polymerization: An Improved Photoinitiation System Based on Amphiphilic Tertiary Amine N‐Oxides
Authors: Shen Kaihua , Jiang Yanfeng , Liu Zhengxue , Qi Debang , Wang Haiyang , Li Yang
Published: September 2015

A new method for visible‐induced emulsion polymerization is successfully demonstrated. Photo­initiators are used upon irradiation with visible light to undergo sequential photodecomposition, demonstrating an effective way to generate radicals with octadecylamine ethoxylates N‐oxide (AO‐1805, EO = 5). AO‐1805, acting both as a surfactant and mediator simultaneously, is proposed for free radical generation through synergistic effects with the photoinitiator, which differs greatly from organoboron compounds, especially in emulsions. Comparative experiments are carried out with nonylphenol ethoxylates (NP‐10, EO = 5) upon irradiation with UV and visible light in order to examine the nature of the photoinitiated emulsion polymerization with AO‐1805. The laser flash photolysis method is then used to study the interaction between AO‐1805 and free radicals. The emulsion photopolymerization of styrene may be successfully mediated by AO‐1805, with good control over molecular weight. A synergistic effect between radicals and AO‐1805 is observed in the UV irradiation process that can further mediate radical polymerization. In visible light‐induced emulsion polymerization, AO‐1805 also has a novel stabilizing role because of the interaction between D1 and AO‐1805. Moreover, it is hard to see such a trend with the NP‐10/D1 combination, indicating that the functional group (N‐oxide) of AO‐1805 plays an important role in photoinitiation and has an influence on the overall polymerization rate.

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Dissipativity in impulsive systems via Lyapunov functions
Authors: de Mello Bonotto Everaldo , da Costa Ferreira Jaqueline
Published: September 2015

This paper deals with impulsive dissipative semidynamical systems. We present sufficient conditions to obtain dissipativity for autonomous and non‐autonomous systems by using Lyapunov functions. Also, some converse‐type results are presented.
Essential spectrum of singular discrete linear Hamiltonian systems
Authors: Sun Huaqing , Kong Qingkai , Shi Yuming
Published: September 2015

The paper is concerned with the essential spectral points of singular discrete linear Hamiltonian systems. Several sufficient conditions for a real point to be in the essential spectrum are obtained in terms of the number of linearly independent square‐summable solutions of the corresponding homogeneous linear system, and a sufficient and necessary condition for a real point to be in the essential spectrum is given in terms of the number of linearly independent square‐summable solutions of the corresponding nonhomogeneous linear system. As a direct consequence, the corresponding results for singular higher‐order symmetric vector difference expressions are given.
Long non‐coding RNA: A new paradigm for lung cancer
Authors: Khandelwal Akanksha , Bacolla Albino , Vasquez Karen M , Jain Aklank
Published: September 2015

Lung cancer is the leading cause of cancer‐related deaths worldwide. Recent advances in whole genome transcriptome analysis have enabled the identification of numerous members of a novel class of non‐coding RNAs, i.e., long non‐coding RNAs (lncRNAs), which play important roles in a wide range of biological processes and whose deregulation causes human disease, including cancer. Herein we provide a comprehensive survey of lncRNAs associated with lung cancer, with particular focus on the functions that either facilitate or inhibit the progression of lung cancer and the pathways involved. Emerging data on the use of lncRNAs as biomarkers for the diagnosis and prognosis of cancer are also discussed. We cast this information within the wider perspective of lncRNA biogenesis and molecular functions in the cell. Relationships that exist between lncRNAs, genome‐wide transcription, and lung cancer are discussed. Deepening our understanding on these processes is critical not only from a mechanistic standpoint, but also for the development of novel biomarkers and effective therapeutic targets for cancer patients. © 2015 Wiley Periodicals, Inc.
Marinopyrroles: Unique Drug Discoveries Based on Marine Natural Products
Authors: Li Rongshi
Published: September 2015

Natural products provide a successful supply of new chemical entities (NCEs) for drug discovery to treat human diseases. Approximately half of the NCEs are based on natural products and their derivatives. Notably, marine natural products, a largely untapped resource, have contributed to drug discovery and development with eight drugs or cosmeceuticals approved by the U.S. Food and Drug Administration and European Medicines Agency, and ten candidates undergoing clinical trials. Collaborative efforts from drug developers, biologists, organic, medicinal, and natural product chemists have elevated drug discoveries to new levels. These efforts are expected to continue to improve the efficiency of natural product‐based drugs. Marinopyrroles are examined here as a case study for potential anticancer and antibiotic agents.
Microtubule‐Binding Proteins as Promising Biomarkers of Paclitaxel Sensitivity in Cancer Chemotherapy
Authors: Xie Songbo , Ogden Angela , Aneja Ritu , Zhou Jun
Published: September 2015

Microtubules, tirelessly animated and highly dynamic structures, are vital for most cellular processes and their intricacies are still being revealed even after a century since their discovery. The importance of microtubules as chemotherapeutic targets cannot be overstated, and their clinical role is unlikely to abate in the near future. Indeed, improved understanding of microtubule biology could herald a new epoch of anticancer drug design by permitting fine‐tuning of microtubule‐targeting agents, the clinical utility of which is presently often limited by primary or acquired resistance. Paclitaxel, one such agent belonging to the taxane family, has proven a resoundingly successful treatment for many cancer patients; however, for too many others with paclitaxel‐refractory tumors, the drug has offered nothing but side effects. Accumulating evidence suggests that microtubule‐binding proteins (MBPs) can regulate paclitaxel sensitivity in a wide range of cancer types. Improved understanding of how these proteins can be assayed to predict treatment responses or manipulated pharmacologically to improve clinical outcomes could transform modern chemotherapy and is urgently awaited.
A method based on covariance and pattern recognition for improving resolutions of spatially encoded NMR spectra
Authors: Qiu Wenqi , Chen Youhe , Wei Zhiliang , Yang Jian , Lin Yulan , Chen Zhong
Published: September 2015

The spatially encoded technique enables the fast acquisition of two‐dimensional (2D) nuclear magnetic resonance spectrum within a single scan, serving as a powerful tool for studying various systems and phenomena in short time scales. In spatially encoded spectroscopy, the resolution in the direct dimension can be enhanced by increasing effective acquisition times. However, spectral widths and resolutions in indirect dimensions are no longer independent of each other with wider spectral widths yielding lower resolution. The covariance method, which has achieved success in enhancing resolutions in the indirect dimensions of conventional 2D spectroscopy, is employed here to improve resolutions in the spatially encoded dimension. Moreover, an algorithm is developed based on pattern recognition to eliminate artifacts arising from the employment of the covariance method and experimental imperfections in recording the spatially encoded spectra. Therefore, high‐resolution homonuclear 2D correlated spectra are obtained. Experiments are performed to show the feasibility and effectiveness of this proposed method in providing high‐resolution spectra within greatly shortened times. Copyright © 2015 John Wiley & Sons, Ltd.
Improved MRI thermometry with multiple‐echo spirals
Authors: Marx Michael , Butts Pauly Kim
Published: September 2015

Purpose

Low‐bandwidth PRF shift thermometry is used to guide HIFU ablation treatments. Low sampling bandwidth is needed for high signal‐to‐noise ratio with short acquisition times, but can lead to off‐resonance artifacts. In this work, improved multiple‐echo thermometry is presented that allows for high bandwidth and reduced artifacts. It is also demonstrated with spiral sampling, to improve the trade‐off between resolution, speed, and measurement precision.

Methods

Four multiple‐echo thermometry sequences were tested in vivo, one using two‐dimensional Fourier transform (2DFT) sampling and three using spirals. The spiral sequences were individually optimized for resolution, for speed, and for precision. Multifrequency reconstruction was used to correct for off‐resonance spiral artifacts. Additionally, two different multiecho temperature reconstructions were compared.

Results

Weighted combination of per‐echo phase differences gave significantly better precision than least squares off‐resonance estimation. Multiple‐echo 2DFT sequence obtained precision similar to single‐echo 2DFT, while greatly increasing sampling bandwidth. The multiecho spiral acquisitions achieved 2× better resolution, 2.9× better uncertainty, or 3.4× faster acquisition time, without negatively impacting the other two design parameters as compared to single‐echo 2DFT.

Conclusion

Multiecho spiral thermometry greatly improves the capabilities of temperature monitoring, and could improve transcranial treatment monitoring capabilities. Magn Reson Med 76:747–756, 2016. © 2015 Wiley Periodicals, Inc.
Turn‐on fluorogenic and chromogenic detection of cations in complete water media with poly(N‐vinyl pyrrolidone) bearing rhodamine B derivatives as polymeric chemosensor
Authors: Geng Tong‐Mou , Guo Chang , Dong Yan‐Jie , Chen Meng , Wang Yu
Published: September 2015

A hydrophobic organic monomer GRBE with a polymerizable methacrylester moiety had been synthesized by reaction of rhodamine B‐ethanediamine with glycidyl methacrylate. A water‐soluble polymeric chemosensor poly(VP‐GRBE) had been prepared via copolymerization with a hydrophilic comonomer (vinylpyrrolidone) and GRBE, which was able to sense environmentally poisonous cations in completely aqueous media. The chemosensor was a derivative of rhodamine B, which behaved as a fluorescent and chromogenic sensor toward various heavy cations, particularly Cr3+, Fe3+, and Hg2+. Titration curves of Cr3+, Fe3+, and Hg2+ were constructed using rapid, cheap, and widely available technique of fluorescence spectroscopies. The detection limits for Cr3+, Fe3+, or Hg2+ ions were found to be 2.20 × 10−12, 2.39 × 10−12, and 1.11 × 10−12 mol/l in the same medium, respectively. Moreover, a colorimetric response from the polymeric chemosensor permitted the detection of Cr3+, Hg2+, or Fe3+ by “naked eye” because of the development of a pink or brown yellow color when Cr3+, Hg2+, or Fe3+ cations interacted with the copolymer in aqueous media. Copyright © 2015 John Wiley & Sons, Ltd.
Structural characteristics and bonding environment of Ag nanoparticles synthesized by gamma irradiation within thermo‐responsive poly(N‐isopropylacrylamide) hydrogel
Authors: Spasojević Jelena , Radosavljević Aleksandra , Krstić Jelena , Mitrić Miodrag , Popović Maja , Rakočević Zlatko , Kalagasidis‐Krušić Melina , Kačarević‐Popović Zorica
Published: September 2015

To produce well‐defined metal clusters stabilized in protective matrix, poly(N‐isopropylacrylamide) (PNiPAAm) hydrogel with different initial concentration of polymer was used as nanoreactor. The in situ synthesis of well dispersed silver nanoparticles (AgNPs) was performed by gamma irradiation. The obtained AgNPs are spherical in shape with the diameter less than 20 nm. Crystalline properties of nanoparticles such as size, texture coefficient, strain, stress, lattice parameter, d‐spacing, and dislocation density have been calculated using XRD data. Results confirm that the changes of lattice parameter of crystalline AgNPs sensitively reflect their state of strain and stress depending on the formation conditions (i.e., on the concentration of PNiPAAm) and on the diameter of AgNPs. The negative lattice strain and compression stress were observed for the smaller AgNPs (lattice contraction), while for the larger AgNPs are positively strained and under tensile stress (lattice expansion). XPS spectra revealed the donor‐acceptor type of interaction between carbonyl oxygen from PNiPAAm and AgNPs (positive shift of high BE component of O 1s and negative shift of Ag 3d BE). The greater dislocation density of smaller AgNPs incorporated in more concentrated PNiPAAm, resulted in more binding sites and stronger interaction with polymer. POLYM. COMPOS., 38:1014–1026, 2017. © 2015 Society of Plastics Engineers
Roles of chain stiffness and segmental rattling in ionomer glass formation
Authors: Ruan Dihui , Simmons David S.
Published: September 2015

Ionomers–polymers with bound ionic moieties—have received interest for their exceptional properties including high toughness and ion conductivity. One of the primary effects of introduction of covalently bound ions to a polymer is alteration of its glass transition and segmental dynamics. The standard model for these alterations attributes them to a covalent ‘tethering’ effect in which segments near ionic aggregates are immobilized within a range related to the chain persistence length. Here, results from molecular dynamics simulations of glass formation in model ionomers of varying chain stiffness indicate that chain persistence length does not play a central role in ionic‐aggregate‐induced suppression of local segmental dynamics. Instead, these alterations are found to accord with more universal interface‐induced alterations in glass‐forming liquids, consistent with a recent study in which the present authors found a correlation between near‐aggregate mobility suppression and the scale of segmental cooperative rearrangements. In this case, results indicate that shifts in the overall segmental relaxation times of these polymers can be quantitatively rationalized in terms of alterations in the Debye‐Waller factor, reflecting changes in the local picosecond‐timescale segmental rattling. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015, 53, 1458–1469
Androgen deprivation therapy's impact on the mood of prostate cancer patients as perceived by patients and the partners of patients
Authors: Van Dam Dexter , Wassersug Richard J. , Hamilton Lisa Dawn
Published: September 2015

Objective

To assess the relationship between of androgen deprivation therapy (ADT) and the mood of prostate cancer (PCa) patients and partners of PCa patients.

Methods

PCa patients (n = 295) and partners of patients (n = 84) completed an online survey assessing the patients' current mood and mood prior to treatment, relationship adjustment, and sexual function. We compared men on ADT to men who received non‐hormonal treatments for their PCa.

Results

Patients currently treated with ADT (n = 82) reported worsened mood as measured by the Profile of Mood States compared to those not on ADT (n = 213). The negative impact of ADT on mood, however, was reduced in older patients. Partners of patients on ADT (n = 42) reported similar declines in the patient's mood that patients reported, but to a greater degree than patient‐reported levels.

Conclusions

Our data support ADT's impact on PCa patients' mood and verify that partners concurrently see the effects. The psychological changes related to ADT can impact relationships and affect the quality of life of both PCa patients and partners. Patients and their partners are likely to benefit from being well informed about the psychological effects of androgen deprivation on men beginning ADT. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.
The Use of Evolutionary Trajectories to Guide ‘Moving Targets’ in the Management of River Futures
Authors: Brierley G. J. , Fryirs K. A.
Published: September 2015

River histories provide important guidance with which to inform river management. Evolutionary trajectories and appraisals of system responses to changing flux conditions and disturbance events can be used to determine the range of potential future states and associated behavioural regimes, assessing the likelihood that that these states will be attained over a given timeframe. In these analyses, natural or historical reference reaches may not provide a realistic basis to set target conditions for management actions, as what has gone before does not necessarily provide a complete and reliable picture of prospective future conditions. This paper outlines the use of a conceptual tool, the river evolution diagram, as a geomorphic platform to assess river history and the potential range of river futures for any given system. Evolutionary adjustments of a sand bed river in southeastern Australia are used to demonstrate the application of this approach. Applying adaptive management principles, ‘moving targets’ for river management are framed in relation to the range of likely future states and trajectories of adjustment. Copyright © 2015 John Wiley & Sons, Ltd.
Nanodomain analysis with cluster‐SIMS: application to the characterization of macromolecular brush architecture
Authors: Yang Fan , Cho Sangho , Sun Guorong , Verkhoturov Stanislav V. , Thackeray James W. , Trefonas Peter , Wooley Karen L. , Schweikert Emile A.
Published: September 2015

We present the application of cluster‐SIMS for the analysis of the nanoscopic surface of diblock brush terpolymers (DBTs). This novel SIMS technique differs from conventional SIMS. It uses Au4004+ projectiles at 520 keV and an event‐by‐event bombardment/detection regime for the analysis of co‐localized molecular species. The performance of this SIMS method was tested on ‘bottle brush’ block molecules featuring a vertical aligned backbone structure. We were able to assess the extent of secondary ion emissions from the surface and analyze the degree of ordered alignment for DBTs by the fluorocarbon surface coverage. We demonstrate the feasibility of characterizing the homogeneity of macromolecular films at the nanoscale. Copyright © 2015 John Wiley & Sons, Ltd.
Mononuclear 1,3‐Dideazaadenine‐AgI‐Thyminate Base Pairs
Authors: Litau Stefanie , Müller Jens
Published: September 2015

When incorporating a single mispair of 1,3‐dideazaadenine (D) and thymine (T) into a regular B‐DNA duplex, a mononuclear AgI‐mediated D‐AgI‐T base pair is formed upon the addition of AgNO3. The nuclearity of this base pair deviates from that of the previously stablished dinuclear D‐AgI2‐T base pair. Apparently, the geometrical constraints imposed by the surrounding canonicalbase pairs do not allow the incorporation of a second AgI, as the resulting dinuclear D‐AgI2‐T base pair would deviate significantly from planarity. This study demonstrates the importance of neighboring canonical base pairs not only on the stability but also on the identity of an artificial metal‐mediated base pair.
Synthesis, Structure and Magnetic Properties of a MnII Framework Assembled by Two Carboxylate Ligands
Authors: Li Xiaofang , Wu Shuang , Liang Yuning , Chen Zilu
Published: September 2015

The 3D framework [Mn3(CH3COO)2(HCOO)4]n·nDMF (1) was obtained from the assembly of MnII ions with acetate and the in‐situ generated formate ligands. It features Mn‐centered MnMn4 tetrahedral nodes, each of which is linked to another four ones by sharing the apexes to form the 3D framework of 1. Each of the acetate and formate ligands behaves as a syn‐syn:anti bridge to link two apical MnII ions and the central MnII ion. The magnetic measurement of 1 revealed the coexistence of spin‐canted antiferromagnetism and metamagnetism. It represents a typical example to synergistically use two kinds of carboxylate ligands to construct metal‐organic frameworks, as well as to tune the structure and magnetic properties of the aimed complex.
Large‐scale population genetics of the mountain ant Proformica longiseta (Hymenoptera: Formicidae)
Authors: Sanllorente Olivia , Ruano Francisca , Tinaut Alberto
Published: September 2015

Proformica longiseta Collingwood is an endemic ant found in southeastern Spain that inhabits high mountains and is widespread within an altitude range. We have studied the population genetics and biogeography of 14 populations of P. longiseta throughout its distribution using microsatellites and mitochondrial data. Populations are strongly structured for both markers and show isolation by distance, which together with the absence of intra‐population variation in mitochondrial DNA suggest strong female philopatry and limited male dispersal. In spite of this, no recent bottlenecks or inbreeding were detected. Finally, we report on a population currently located where it did not exist 14 years ago, above the usual altitudinal limit known for the species, which may be due to recent colonization enhanced by global warming.
Metabolic profiling as a tool for prioritizing antimicrobial compounds
Authors: Wu Changsheng , Choi Young Hae , van Wezel Gilles P
Published: September 2015

Metabolomics is an analytical technique that allows scientists to globally profile low molecular weight metabolites between samples in a medium- or high-throughput environment. Different biological samples are statistically analyzed and correlated to a bioactivity of interest, highlighting differentially produced compounds as potential biomarkers. Here, we review NMR- and MS-based metabolomics as technologies to facilitate the identification of novel antimicrobial natural products from microbial sources. Approaches to elicit the production of poorly expressed (cryptic) molecules are thereby a key to allow statistical analysis of samples to identify bioactive markers, while connection of compounds to their biosynthetic gene cluster is a determining step in elucidating the biosynthetic pathway and allows downstream process optimization and upscaling. The review focuses on approaches built around NMR-based metabolomics, which enables efficient dereplication and guided fractionation of (antimicrobial) compounds.
Increased valinomycin production in mutants of Streptomyces sp. M10 defective in bafilomycin biosynthesis and branched-chain α-keto acid dehydrogenase complex expression
Authors: Lee Dong Wan , Ng Bee Gek , Kim Beom Seok
Published: September 2015

Streptomyces sp. M10 is a valinomycin-producing bacterial strain that shows potent bioactivity against Botrytis blight of cucumber plants. During studies to increase the yield of valinomycin (a cyclododecadepsipeptide) in strain M10, additional antifungal metabolites, including bafilomycin derivatives (macrolide antibiotics), were identified. To examine the effect of bafilomycin biosynthesis on valinomycin production, the bafilomycin biosynthetic gene cluster was cloned from the genome of strain M10, as were two branched-chain α-keto acid dehydrogenase (BCDH) gene clusters related to precursor supply for bafilomycin biosynthesis. A null mutant (M10bafm) of one bafilomycin biosynthetic gene (bafV) failed to produce bafilomycin, but resulted in a 1.2- to 1.5-fold increase in the amount of valinomycin produced. In another null mutant (M10bkdFm) of a gene encoding a subunit of the BCDH complex (bkdF), bafilomycin production was completely abolished and valinomycin production increased fourfold relative to that in the wild-type M10 strain. The higher valinomycin yield was likely the result of redistribution of the metabolic flux from bafilomycin to valinomycin biosynthesis, because the two antibiotics share a common precursor, 2-ketoisovaleric acid, a deamination product of valine. The results show that directing precursor flux toward active ingredient biosynthesis could be used as a prospective tool to increase the competence of biofungicides.
Beyond a diagnosis: The experience of depression among clinically‐referred adolescents
Authors: Midgley Nick , Parkinson Sally , Holmes Josh , Stapley Emily , Eatough Virginia , Target Mary
Published: August 2015

Policy‐makers have identified an urgent need to improve our ability to detect and diagnose depression in adolescents. This study aims to explore the lived experience of depression in clinically referred adolescents. 77 adolescents, aged between 11 and 17 with moderate to severe depression, were interviewed as part of a randomised controlled trial, using the Expectations of Therapy Interview. Data were analysed qualitatively using framework analysis, with a focus on how the adolescents spoke about their depression. The study identified five themes: 1) Misery, despair and tears; 2) Anger and violence towards self and others; 3) A bleak view of everything; 4) Isolation and cutting off from the world; and 5) The impact on education. Researchers and policy‐makers need to develop an understanding of depression grounded in the experiences of adolescents to improve detection and diagnosis of depression.
Elastin‐like polypeptides as models of intrinsically disordered proteins
Authors: Roberts Stefan , Dzuricky Michael , Chilkoti Ashutosh
Published: August 2015

Elastin‐like polypeptides (ELPs) are a class of stimuli‐responsive biopolymers inspired by the intrinsically disordered domains of tropoelastin that are composed of repeats of the VPGXG pentapeptide motif, where X is a “guest residue”. They undergo a reversible, thermally triggered lower critical solution temperature (LCST) phase transition, which has been utilized for a variety of applications including protein purification, affinity capture, immunoassays, and drug delivery. ELPs have been extensively studied as protein polymers and as biomaterials, but their relationship to other disordered proteins has heretofore not been established. The biophysical properties of ELPs that lend them their unique material behavior are similar to the properties of many intrinsically disordered proteins (IDP). Their low sequence complexity, phase behavior, and elastic properties make them an interesting “minimal” artificial IDP, and the study of ELPs can hence provide insights into the behavior of other more complex IDPs. Motivated by this emerging realization of the similarities between ELPs and IDPs, this review discusses the biophysical properties of ELPs, their biomedical utility, and their relationship to other disordered polypeptide sequences.
Blast traumatic brain injury–induced cognitive deficits are attenuated by preinjury or postinjury treatment with the glucagon‐like peptide‐1 receptor agonist, exendin‐4
Authors: Tweedie David , Rachmany Lital , Rubovitch Vardit , Li Yazhou , Holloway Harold W. , Lehrmann Elin , Zhang Yongqing , Becker Kevin G. , Perez Evelyn , Hoffer Barry J. , Pick Chaim G. , Greig Nigel H.
Published: August 2015

Introduction

Blast traumatic brain injury (B‐TBI) affects military and civilian personnel. Presently, there are no approved drugs for blast brain injury.

Methods

Exendin‐4 (Ex‐4), administered subcutaneously, was evaluated as a pretreatment (48 hours) and postinjury treatment (2 hours) on neurodegeneration, behaviors, and gene expressions in a murine open field model of blast injury.

Results

B‐TBI induced neurodegeneration, changes in cognition, and genes expressions linked to dementia disorders. Ex‐4, administered preinjury or postinjury, ameliorated B‐TBI–induced neurodegeneration at 72 hours, memory deficits from days 7–14, and attenuated genes regulated by blast at day 14 postinjury.

Discussion

The present data suggest shared pathologic processes between concussive and B‐TBI, with end points amenable to beneficial therapeutic manipulation by Ex‐4. B‐TBI–induced dementia‐related gene pathways and cognitive deficits in mice somewhat parallel epidemiologic studies of Barnes et al. who identified a greater risk in US military veterans who experienced diverse TBIs, for dementia in later life.
Multisite assessment of NIA‐AA guidelines for the neuropathologic evaluation of Alzheimer's disease
Authors: Montine Thomas J. , Monsell Sarah E. , Beach Thomas G. , Bigio Eileen H. , Bu Yunqi , Cairns Nigel J. , Frosch Matthew , Henriksen Jonathan , Kofler Julia , Kukull Walter A. , Lee Edward B. , Nelson Peter T. , Schantz Aimee M. , Schneider Julie A. , Sonnen Joshua A. , Trojanowski John Q. , Vinters Harry V. , Zhou Xiao‐Hua , Hyman Bradley T.
Published: August 2015

Introduction

Neuropathologic assessment is the current “gold standard” for evaluating the Alzheimer's disease (AD), but there is no consensus on the methods used.

Methods

Fifteen unstained slides (8 brain regions) from each of the 14 cases were prepared and distributed to 10 different National Institute on Aging AD Centers for application of usual staining and evaluation following recently revised guidelines for AD neuropathologic change.

Results

Current practice used in the AD Centers Program achieved robustly excellent agreement for the severity score for AD neuropathologic change (average weighted κ = .88, 95% confidence interval: 0.77–0.95) and good‐to‐excellent agreement for the three supporting scores. Some improvement was observed with consensus evaluation but not with central staining of slides. Evaluation of glass slides and digitally prepared whole‐slide images was comparable.

Discussion

AD neuropathologic evaluation as performed across AD Centers yields data that have high agreement with potential modifications for modest improvements.
Efficacy of bilateral thoracoscopic sympathectomy in a patient with catecholaminergic polymorphic ventricular tachycardia
Authors: Okajima Katsunori , Kiuchi Kunihiko , Yokoi Kiminobu , Teranishi Jin , Aoki Kosuke , Shimane Akira , Nakamura Yoshihide , Kimura Motoko , Horikawa Yoshio , Yoshida Masato , Maniwa Yoshimasa
Published: August 2015

A 27‐year‐old woman with frequent implantable cardioverter defibrillator (ICD) shocks related to catecholaminergic polymorphic ventricular tachycardia (VT) experienced aborted sudden death due to incessant polymorphic VT despite the administration of beta‐blockers, verapamil, and flecainide. Catheter ablation failed to suppress the polymorphic VT. Based on the temporary efficacy of the local anesthetic administered at the left and right cervical sympathetic nerves to suppress VT under an isoproterenol infusion, stepwise, bilateral thoracoscopic sympathectomy was performed. Postoperatively, no further VT or syncopal episodes were documented under ICD telemetry. Bilateral thoracoscopic sympathectomy may be an alternative for patients with drug‐refractory catecholaminergic polymorphic VT.
Regional Nerve Blocks For Hip and Femoral Neck Fractures in the Emergency Department: A Systematic Review
Authors: Ritcey Brandon , Pageau Paul , Woo Michael Y. , Perry Jeffrey J.
Published: September 2015

Objectives

Hip and femoral neck fractures are common in elderly patients, who are at an increased risk of complications if their pain is suboptimally managed. This systematic review seeks to determine if regional nerve blocks reduce pain, reduce the need for parenteral opiates, and reduce complications, compared to standard pain management with opiates, acetaminophen, or NSAIDs.

Data sources

Systematic review of MEDLINE, EMBASE, CINAHL, and the Cochrane Central Register of Controlled Trials found 401 articles, of which nine were selected for inclusion.

Study selection

Randomized controlled trials including adult patients with a hip or femoral neck fracture (Population) who had a 3-in-1 femoral nerve block, traditional femoral nerve block, or fascia iliaca compartment block performed preoperatively (Intervention). Comparison must have been made with standard pain management with opiates, acetaminophen, or NSAIDs (Comparison) and outcomes must have included pain score reduction (Outcome).

Data synthesis

Eight out of nine studies concluded pain scores were improved with the regional nerve block compared to standard pain management. A significant reduction in parenteral opiate use was seen in five out of six studies. No patients suffered life-threatening complications related to the nerve block; however, more minor complications were under-reported. Most of the studies were at a moderate to high risk of bias.

Conclusions

Regional nerve blocks for hip and femoral neck fractures have a benefit in reducing pain and the need for IV opiates. The use of these blocks can be recommended for these patients. Further high-quality randomized controlled trials are required.
Cerebral Vasospasm: A Review
Authors: Findlay J. Max , Nisar Joshua , Darsaut Tim
Published: September 2015

Cerebral vasospasm is a prolonged but reversible narrowing of cerebral arteries beginning days after subarachnoid hemorrhage. Progression to cerebral ischemia is tied mostly to vasospasm severity, and its pathogenesis lies in artery encasement by blood clot, although the complex interactions between hematoma and surrounding structures are not fully understood. The delayed onset of vasospasm provides a potential opportunity for its prevention. It is disappointing that recent randomized, controlled trials did not demonstrate that the endothelin antagonist clazosentan, the cholesterol-lowering agent simvastatin, and the vasodilator magnesium sulfate improve patient outcome. Minimizing ischemia by avoiding inadequate blood volume and pressure, administering the calcium antagonist nimodipine, and intervention with balloon angioplasty, when necessary, constitutes current best management. Over the past two decades, our ability to manage vasospasm has led to a significant decline in patient morbidity and mortality from vasospasm, yet it still remains an important determinant of outcome after aneurysm rupture.
Significance of Non-phase Locked Oscillatory Brain Activity in Response to Noxious Stimuli
Authors: Dufort Rouleau Raphaël , Lagrandeur Lydia , Daigle Kathya , Lorrain Dominique , Léonard Guillaume , Whittingstall Kevin , Goffaux Philippe
Published: September 2015

Background: Although current pain-evoked electroencephalographic (EEG) studies provide valuable information regarding human brain regions involved in pain, they have mostly considered neuronal responses which oscillate in phase following a painful event. In many instances, cortical neurons respond by generating bursts of activity that are slightly out of phase from trial-to-trial. These types of activity bursts are known as induced brain responses. The significance of induced brain responses to pain is still unknown. Methods: In this study, 23 healthy subjects were given both non-painful and painful transcutaneous electrical stimulations in separate testing blocks (stimulation strength was kept constant within blocks). Subjective intensity was rated using a numerical rating scale, while cerebral activity tied to each stimulation was measured using EEG recordings. Induced brain responses were identified using a time frequency wavelet transform applied to average-removed single trials. Results: Results showed a pain-specific burst of induced theta activity occurring between 180 and 500 ms post-shock onset. Source current density estimations located this activity within the dorsolateral prefrontal cortex (DLPFC, bilaterally), however, only right DLPFC activity predicted a decrease in subjective pain as testing progressed. Conclusion: This finding suggests that non-phase locked neuronal responses in the right DLPFC contribute to the endogenous attenuation of pain through time. Perspective: This article presents neuroimaging findings demonstrating that, in response to pain, non-phase locked bursts of theta activity located in the right dorsolateral prefrontal cortex are associated with a progressive decrease in subjective pain intensity, which has potentially important implications regarding how humans endogenously control their experiences of pain.
Black Power on the Telly: America, Television, and Race in 1960s and 1970s Britain
Authors: Waters Rob
Published: September 2015

This paper proposes the importance of television, the televisation of US and British race politics, and the framing of “Black Power” in this television coverage, for race politics in Britain in the late 1960s and early 1970s. British politics and culture was “re-racialized” in the postwar era, and television, for white and black Britons, became a site of racial knowledge, racial identification, and racial dislocation. The rise of television as a central medium of everyday life saw it emerge, too, as a central site for the imagination of community. As critics have long noted, the community imagined in British television programming of this era was overwhelmingly white, and black people were featured most often only as a marker of social difference or social “problems.” Many black Britons, excluded from the national “everyday” as it was constituted on television, and facing increasing institutional and interpersonal racism in daily life, found in coverage of the burgeoning black liberation movements of the United States a useable politics through which to articulate new sites of identification, community, and solidarity. For others, though, coverage of race politics in the United States could be a source of anxiety and alarm. The televisation of US race politics was central to the growth of cultures and politics of radical blackness in Britain, but it also reconstituted the politics of white racism, recasting blackness in Britain as a sign of violence and impending social disorder.
A multiscale dynamo model driven by quasi-geostrophic convection
Authors: Calkins Michael A. , Julien Keith , Tobias Steven M. , Aurnou Jonathan M.
Published: September 2015

A convection-driven multiscale dynamo model is developed in the limit of low Rossby number for the plane layer geometry in which the gravity and rotation vectors are aligned. The small-scale fluctuating dynamics are described by a magnetically modified quasi-geostrophic equation set, and the large-scale mean dynamics are governed by a diagnostic thermal wind balance. The model utilizes three time scales that respectively characterize the convective time scale, the large-scale magnetic evolution time scale and the large-scale thermal evolution time scale. Distinct equations are derived for the cases of order one and low magnetic Prandtl number. It is shown that the low magnetic Prandtl number model is characterized by a magnetic to kinetic energy ratio that is asymptotically large, with ohmic dissipation dominating viscous dissipation on the large scale. For the order one magnetic Prandtl number model, the magnetic and kinetic energies are equipartitioned and both ohmic and viscous dissipation are weak on the large scales; large-scale ohmic dissipation occurs in thin magnetic boundary layers adjacent to the horizontal boundaries. For both magnetic Prandtl number cases the Elsasser number is small since the Lorentz force does not enter the leading order force balance. The new models can be considered fully nonlinear, generalized versions of the dynamo model originally developed by Childress & Soward (Phys. Rev. Lett., vol. 29, 1972, pp. 837–839), and provide a new theoretical framework for understanding the dynamics of convection-driven dynamos in regimes that are only just becoming accessible to direct numerical simulations.
Inequality, Aspirations, and Social Comparisons
Authors: Bendor Jonathan , Diermeier Daniel , Ting Michael M.
Published: September 2015

We develop a model of adaptive learning with social comparisons. Actors are more likely to choose actions that recently yielded satisfactory payoffs; satisfaction is evaluated relative to an aspiration level that reflects previous payoffs and possibly other players’ payoffs. This captures the phenomenon of social comparison viareference groups. We show that if agents compare themselves to those who are receiving higher payoffs then in stable outcomes all payoffs must be equal. If, however, agents’ aspirations are driven by less ambitious social comparisons then very unequal distributions can be stable. We apply our general results to collective action problems in socio-political hierarchies and derive conditions for stable exploitation. Finally, we develop a computational model, which shows that increases in payoff inequality make outcomes less stable.
Effects of a quercetin-rich onion skin extract on 24 h ambulatory blood pressure and endothelial function in overweight-to-obese patients with (pre-)hypertension: a randomised double-blinded placebo-controlled cross-over trial
Authors: Brüll Verena , Burak Constanze , Stoffel-Wagner Birgit , Wolffram Siegfried , Nickenig Georg , Müller Cornelius , Langguth Peter , Alteheld Birgit , Fimmers Rolf , Naaf Stefanie , Zimmermann Benno F. , Stehle Peter , Egert Sarah
Published: September 2015

The polyphenol quercetin may prevent CVD due to its antihypertensive and vasorelaxant properties. We investigated the effects of quercetin after regular intake on blood pressure (BP) in overweight-to-obese patients with pre-hypertension and stage I hypertension. In addition, the potential mechanisms responsible for the hypothesised effect of quercetin on BP were explored. Subjects (n70) were randomised to receive 162 mg/d quercetin from onion skin extract powder or placebo in a double-blinded, placebo-controlled cross-over trial with 6-week treatment periods separated by a 6-week washout period. Before and after the intervention, ambulatory blood pressure (ABP) and office BP were measured; urine and blood samples were collected; and endothelial function was measured by EndoPAT technology. In the total group, quercetin did not significantly affect 24 h ABP parameters and office BP. In the subgroup of hypertensives, quercetin decreased 24 h systolic BP by −3·6 mmHg (P=0·022) when compared with placebo (mean treatment difference, −3·9 mmHg;P=0·049). In addition, quercetin significantly decreased day-time and night-time systolic BP in hypertensives, but without a significant effect in inter-group comparison. In the total group and also in the subgroup of hypertensives, vasoactive biomarkers including endothelin-1, soluble endothelial-derived adhesion molecules, asymmetric dimethylarginine, angiotensin-converting enzyme activity, endothelial function, parameters of oxidation, inflammation, lipid and glucose metabolism were not affected by quercetin. In conclusion, supplementation with 162 mg/d quercetin from onion skin extract lowers ABP in patients with hypertension, suggesting a cardioprotective effect of quercetin. The mechanisms responsible for the BP-lowering effect remain unclear.
A FLEXIBLE NONPARAMETRIC TEST FOR CONDITIONAL INDEPENDENCE
Authors: Huang Meng , Sun Yixiao , White Halbert
Published: September 2015

This paper proposes a nonparametric test for conditional independence that is easy to implement, yet powerful in the sense that it is consistent and achievesn−1/2local power. The test statistic is based on an estimator of the topological “distance” between restricted and unrestricted probability measures corresponding to conditional independence or its absence. The distance is evaluated using a family ofGenerically Comprehensively Revealing(GCR) functions, such as the exponential or logistic functions, which are indexed by nuisance parameters. The use of GCR functions makes the test able to detect any deviation from the null. We use a kernel smoothing method when estimating the distance. An integrated conditional moment (ICM) test statistic based on these estimates is obtained by integrating out the nuisance parameters. We simulate the critical values using a conditional simulation approach. Monte Carlo experiments show that the test performs well in finite samples. As an application, we test an implication of the key assumption of unconfoundedness in the context of estimating the returns to schooling.
Prevalence and determinants of anaemia among children aged 0–59 months in a rural region of Armenia: a case–control study
Authors: Demirchyan Anahit , Petrosyan Varduhi , Sargsyan Viktoria , Hekimian Kim
Published: September 2015

Objective

Despite the trend of increasing prevalence of childhood anaemia in Armenia, no studies exploring its risk factors have been conducted in the country. The present study aimed to investigate the prevalence and determinants of childhood anaemia in rural Armenia.

Design

Blood Hb level was measured among a representative sample of children using the HemoCue Hb201+ analyser. The revealed cases with anaemia were compared with randomly selected non-anaemic controls. Mothers of cases and controls were interviewed. Logistic and linear regression models were fitted to identify the risk factors of anaemia and low Hb level, respectively.

Setting

Talin communities, Aragatsotn Province, Armenia.

Subjects

Children under 5 years of age in Talin region.

Results

Of the 729 studied children, 32·4 % were anaemic with 14·7 % having moderate/severe anaemia. Infants were the most affected group with 51·1 % being anaemic before 6 months and 67·9 % at 6–12 months of age. Fitted regression models identified the following predictors of anaemia: younger age, male gender, shorter birth length, anaemia during pregnancy, lower meal frequency per day, lack of meat in the diet, using dung cakes for heating and living in a community that received an incomplete set of nutrition interventions.

Conclusions

The study identified several modifiable risk factors that could be targeted to reduce childhood anaemia in rural Armenia and, possibly, in rural areas in other low-/middle-income countries. The suggested interventions include prevention and treatment of anaemia during pregnancy, provision of adequate complementary feeding to children with inclusion of meat in their daily diet and reduction of their exposure to biomass fuel smoke.
Mass occurrence of Salpa fusiformis and records of the rare salps Cyclosalpa bakerii and Thetys vagina from northern Scotland
Authors: Shucksmith Rachel J.
Published: September 2015

Gelatinous zooplankton including salps are an important but often overlooked component of marine ecosystems. This study documents a bloom ofSalpa fusiformisat five locations to the north of mainland Scotland. The bloom was observed at Sula Stack, Sula Sgeir, North Rona and at two other locations to the west coast of the Orkney Islands. Salp blooms have the potential to deplete phytoplankton biomass, impacting on other zooplankton, including copepods and fish larvae. New records of two rare salpsCyclosalpa bakeriiandThetys vaginaare also documented from North Rona and Skirza Head, Caithness. These specimens were observed in the aggregate (sexual) form. These observations represent the second record in the UK ofC. bakeriiand the third and fourth records ofT. vagina.