bluuebunny/crossref_metadata_2025 huggingface dataset:
Quantitative electromyography in ambulatory boys with Duchenne muscular dystrophy
Authors: Verma Sumit , Lin Jenny , Travers Curtis , McCracken Courtney , Shah Durga
Published: April 2017

Introduction

This study's objective was to evaluate quantitative electromyography (QEMG) using multiple‐motor‐unit (multi‐MUP) analysis in Duchenne muscular dystrophy (DMD).

Methods

Ambulatory DMD boys, aged 5–15 years, were evaluated with QEMG at 6‐month intervals over 14 months. EMG was performed in the right biceps brachii (BB) and tibialis anterior (TA) muscles. Normative QEMG data were obtained from age‐matched healthy boys. Wilcoxon signed‐rank tests were performed.

Results

Eighteen DMD subjects were enrolled, with a median age of 7 (interquartile range 7–10) years. Six‐month evaluations were performed on 14 subjects. QEMG showed significantly abnormal mean MUP duration in BB and TA muscles, with no significant change over 6 months.

Conclusions

QEMG is a sensitive electrophysiological marker of myopathy in DMD. Preliminary data do not reflect a significant change in MUP parameters over a 6‐month interval; long‐term follow‐up QEMG studies are needed to understand its role as a biomarker for disease progression. Muscle Nerve 56: 1361–1364, 2017
Modulation of ionization and structural properties of weak polyelectrolytes due to 1D, 2D, and 3D confinement
Authors: Mella Massimo , Izzo Lorella
Published: May 2017

What is the impact of reducing the space available to molecules onto their properties is a fundamental question for capillary systems, molecular biology and transport, protein and material sciences. Possibly influenced by space restriction, ionization degree has rarely been studied for confined polyelectrolytes; Monte Carlo titrations and coarse‐grained models are thus used to investigate structural and ionization changes induced on a single polyelectrolyte chain by confinement into slit (1D), cylindrical (2D), or spherical (3D) cavities. Four polyelectrolyte models differing in chain stiffness and the possible formation of charged hydrogen bonds (cHbonds) are studied. Low pH effective ionization constants (pKa) of confined chains are lower than for the free species if cHbonds can be formed. This is especially evident for 3D‐confined stiff chains, a finding rationalized by the impact of global compression onto chain conformations. If no cHbonds are allowed, chain ionization is largely unaffected by 1D or 2D confinement, while it is depressed by 3D. Chain confinement Helmholtz energy (ΔAconf) was computed as a function of both pH and confining width (W) to gauge the impact of ionization‐induced stiffening onto ΔAconf versus W behavior, the partition coefficient
governing absorption, and the average number of cHbond formed. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017, 55, 1088–1102
Reading‐Related Causal Attributions for Success and Failure: Dynamic Links With Reading Skill
Authors: Frijters Jan C. , Tsujimoto Kimberley C. , Boada Richard , Gottwald Stephanie , Hill Dina , Jacobson Lisa A. , Lovett Maureen W. , Mahone E. Mark , Willcutt Erik G. , Wolf Maryanne , Bosson‐Heenan Joan , Gruen Jeffrey R.
Published: April 2017

The present study investigated the relation among reading skills and attributions, naming speed, and phonological awareness across a wide range of reading skill. Participants were 1,105 school‐age children and youths from two understudied populations: African Americans and Hispanic Americans. Individual assessments of children ranging in age from 8 to 15 years were conducted for reading outcomes, cognitive and linguistic predictors of reading, and attributions for success and failure in reading situations. Quantile regressions were formulated to estimate these relations across the full skill span of each outcome. Reading‐related attributions predicted contextual word recognition, sight word and decoding fluency, and comprehension skills. Attributions to ability in success situations were positively related to each outcome across the full span. On three reading outcomes, this relation strengthened at higher skill levels. Attributions to effort in success situations were consistently and negatively related to all reading outcomes. The results provide evidence that the strength of the relation between reading and attributions varies according to reading skill levels, with the strongest evidence for ability‐based attributions in situations of reading success.
Goal Attainment Scaling in Action Research: Enhancing a Systems Thinking Orientation
Authors: Piggot‐Irvine Eileen , Ferkins Lesley , Cady Phil
Published: May 2017

Awareness of conducting action research (AR) with a systems thinking orientation is increasing. We consider such orientation to be a fundamental, grounding, feature of AR. However, little exploration has occurred of how evaluation activity within AR, using a tool such as Goal Attainment Scaling (GAS), might enhance this orientation. We offer an argument for utilizing GAS to not only broaden action and deepen the research in individual AR projects, but also, for learning more about AR at a meta‐level where there is the increased complexity when evaluating multiple AR projects in diverse contexts. As well as theorizing the concepts noted, an outline of the way the evaluative study of action research (ESAR) customized and deployed GAS for evaluation of AR at both individual and meta‐levels is provided. The paper is a unique contribution to the domains of AR, systems thinking and evaluation methods. Copyright © 2017 John Wiley & Sons, Ltd.
Systems biology of cellular membranes: a convergence with biophysics
Authors: Chabanon Morgan , Stachowiak Jeanne C. , Rangamani Padmini
Published: May 2017

Systems biology and systems medicine have played an important role in the last two decades in shaping our understanding of biological processes. While systems biology is synonymous with network maps and ‘‐omics’ approaches, it is not often associated with mechanical processes. Here, we make the case for considering the mechanical and geometrical aspects of biological membranes as a key step in pushing the frontiers of systems biology of cellular membranes forward. We begin by introducing the basic components of cellular membranes, and highlight their dynamical aspects. We then survey the functions of the plasma membrane and the endomembrane system in signaling, and discuss the role and origin of membrane curvature in these diverse cellular processes. We further give an overview of the experimental and modeling approaches to study membrane phenomena. We close with a perspective on the converging futures of systems biology and membrane biophysics, invoking the need to include physical variables such as location and geometry in the study of cellular membranes. WIREs Syst Biol Med 2017, 9:e1386. doi: 10.1002/wsbm.1386

This article is categorized under:

Models of Systems Properties and Processes > Cellular Models

Biological Mechanisms > Cell Signaling

Models of Systems Properties and Processes > Mechanistic Models
A Different Kind of Craving: Incidence and Treatment of Pica After Laparoscopic Roux‐en‐Y Gastric Bypass
Authors: Van Osdol Andrew D. , Kallies Kara J. , Fredrickson Kyla A. , Kothari Shanu N.
Published: May 2017

Background

Iron deficiency can occur in patients after Roux‐en‐y gastric bypass due to altered absorption. Pica, the compulsive craving and intake of non‐nutritive substances, is a rare and poorly understood presentation of iron deficiency. To our knowledge, the rate of pica after RYGB has never been reported.

Methods

The medical records of patients who underwent laparoscopic RYGB from 2001 to 2011 were reviewed. Patients with pica or other abnormal cravings were identified.

Results

Pica was identified in 16/959 (1.7%) patients who underwent RYGB during the study period. The most common presenting sign was pagophagia. All patients with pica were female and had multiple risk factors for iron deficiency with 13/16 being premenopausal and 7/16 non‐compliant with oral iron supplementation. Pica symptoms presented at a mean of 3.9 ± 1.9 years after RYGB. Iron deficiency was identified in all 16 patients, with a median ferritin level of 5.0 ng/mL (range 2–27). All 16 patients received intravenous iron and pica symptoms resolved.

Conclusions

Pica is a rare phenomenon associated with iron deficiency and can occur despite oral iron supplementation. In our experience, intravenous iron can relieve symptoms. Patients considering bariatric surgery should be counseled on pica. Patients with unusual cravings should be evaluated for iron deficiency.
Description and genetic characterization of a newContracaecumlarval type (Nematoda: Anisakidae) from Australia
Authors: Shamsi S. , Turner A. , Wassens S.
Published: May 2017

Nematode parasites belonging to the genusContracaecumare economically important parasites with zoonotic significance. AdultContracaecumspp. are found in the stomach of marine mammals or piscivorous birds, and larval stages infect a wide range of invertebrates and fish species. Human infection withContracaecumlarvae has been reported in Australia and other countries after the consumption of infected fish. Although the genusContracaecumcomprises numerous species, thus far only fourContracaecumlarval types have been specifically identified, therefore their life cycle and biology are not yet fully understood. In this study, a newContracaecumlarva (type IV), found in the intestinal tissue of carp caught from Coonancoocabil Lagoon, New South Wales, Australia, is described and characterized genetically. It was identified asContracaecum bancrofti,a unique Australian species reported previously from the Australian pelican in Northern Territory, New South Wales, Victoria and South Australia. This study highlights the role of migratory birds and introduced fish species, such as carp, in distributing zoonotic pathogens not only across the continent but also from marine to freshwater systems. Coonancoocabil Lagoon is located in the Murrumbidgee Valley National Park, a highly managed conservation area with native fish in wetlands located in close proximity to several fish farms and hatcheries. Infection of a highly resilient invasive fish species, such as carp, with a zoonotic parasite of low host specificity, such asContracaecumlarvae, should be alarming for aquaculture and environmental authorities.
The role of PD‐1 in regulation of macrophage apoptosis and its subversion by Leishmania donovani
Authors: Roy Shalini , Gupta Purnima , Palit Shreyasi , Basu Moumita , Ukil Anindita , Das Pijush K
Published: May 2017

Programmed death‐1 receptor (PD‐1) expressed in many immune cells is known to trigger T‐cell exhaustion but the significance of macrophage‐associated PD‐1 in relevance to macrophage apoptosis is not known. This study is aimed to delineate whether PD‐1 pathway has any role in eliciting macrophage apoptosis and, if so, then how the intra‐macrophage parasite, Leishmania donovani modulates PD‐1 pathway for protecting its niche. Resting macrophages when treated with H2O2 showed increased PD‐1 expression and apoptosis, which was further enhanced on PD‐1 agonist treatment. The administration of either PD‐1 receptor or PD‐1 ligand‐blocking antibodies reversed the process thus documenting the involvement of PD‐1 in macrophage apoptosis. On the contrary, L. donovani‐infected macrophages showed decreased PD‐1 expression concurrent with inhibition of apoptosis. The activation of PD‐1 pathway was found to negatively regulate the phosphorylation of pro‐survival AKT, which was reversed during infection. Infection‐induced PD‐1 downregulation led to the activation of AKT resulting in phosphorylation and subsequent inhibition of proapoptotic protein BAD. Strong association of SHP2 (a SH2‐containing ubiquitously expressed tyrosine‐specific protein phosphatase) with PD‐1 along with AKT deactivation observed in H2O2‐treated macrophages was reversed by L. donovani infection. Kinetic analysis coupled with inhibitor‐based approach and knockdown experiments demonstrated that L. donovani infection actively downregulated the PD‐1 by deactivating NFATc1 as revealed by its reduced nuclear translocation. The study thus elucidates the detailed mechanism of the role of PD‐1 in macrophage apoptosis and its negative modulation by Leishmania for their intracellular survival.
Nickel-catalysed retro-hydroamidocarbonylation of aliphatic amides to olefins
Authors: Hu Jiefeng , Wang Minyan , Pu Xinghui , Shi Zhuangzhi
Published: May 2017

Amide and olefins are important synthetic intermediates with complementary reactivity which play a key role in the construction of natural products, pharmaceuticals and manmade materials. Converting the normally highly stable aliphatic amides into olefins directly is a challenging task. Here we show that a Ni/NHC-catalytic system has been established for decarbonylative elimination of aliphatic amides to generate various olefins via C–N and C–C bond cleavage. This study not only overcomes the acyl C–N bond activation in aliphatic amides, but also encompasses distinct chemical advances on a new type of elimination reaction called retro-hydroamidocarbonylation. This transformation shows good functional group compatibility and can serve as a powerful synthetic tool for late-stage olefination of amide groups in complex compounds.
ZnO@C (core@shell) microspheres derived from spent coffee grounds as applicable non-precious electrode material for DMFCs
Authors: Ghouri Zafar Khan , Al-Meer Saeed , Barakat Nasser A. M. , Kim Hak Yong
Published: May 2017

Although numerous reports have introduced non precious electrocatalysts for methanol oxidation, most of those studies did not consider the corresponding high onset potential which restricts utilization in real fuel cells. In this study, an −90 mV [vs. Ag/AgCl] onset potential non-precious electrocatalyst is introduced as an applicable anode material for the direct methanol fuel cells. Moreover, the proposed material was prepared from a cheap and abundantly existing resource; the spent coffee grounds. Typically, the spent coffee grounds were facilely converted to core@shell (ZnO@C) microspheres through a two-step approach, involving chemical activation and a subsequent calcination at temperature of 700 °C. Activation of the carbon derived from the spent coffee grounds was performed with ZnCl2 which acts as pore-forming agent as well as a precursor for the ZnO. The structure and morphology were characterized by (XRD), (SEM), and (TEM) analyses while the electrochemical characterizations was evaluated by cyclic voltammetry (CV) technique. Besides the comparatively very low onset potential, the introduced microspheres exhibited relatively high current density; 17 mA/cm2. Overall, based on the advantages of the green source of carbon and the good electrocatalytic activity, the spent coffee grounds-derived carbon can be considered a promise anode material for the DMFCs.
A Photochemical Avenue to Photoluminescent N-Dots and their Upconversion Cell Imaging
Authors: Jin Qingqing , Gubu Amu , Chen Xiuxian , Tang Xinjing
Published: May 2017

A photochemical avenue to synthesize nitrogen-rich quantum dots (N-dots) using 2-azido imidazole as the starting material was established for the first time. A production yield of up to 92.7% was obtained. The N-dots were then fully characterized by elemental analysis, IR, XPS, XRD, AFM and TEM. On the basis of the N2 production and in situ IR results, the underlying mechanism for the photochemical formation of N-dots was proposed. These N-dots showed promising optical properties including wavelength-dependent upconversion photoluminescence, and were successfully used in upconversion cell imaging.
Symmetry breaking during homodimeric assembly activates an E3 ubiquitin ligase
Authors: Ye Zhaofeng , Needham Patrick G. , Estabrooks Samuel K. , Whitaker Susan K. , Garcia Brandon L. , Misra Saurav , Brodsky Jeffrey L. , Camacho Carlos J.
Published: May 2017

C-terminus of Hsc/p70-Interacting Protein (CHIP) is a homodimeric E3 ubiquitin ligase. Each CHIP monomer consists of a tetratricopeptide-repeat (TPR), helix-turn-helix (HH), and U-box domain. In contrast to nearly all homodimeric proteins, CHIP is asymmetric. To uncover the origins of asymmetry, we performed molecular dynamics simulations of dimer assembly. We determined that a CHIP monomer is most stable when the HH domain has an extended helix that supports intra-monomer TPR-U-box interaction, blocking the E2-binding surface of the U-box. We also discovered that monomers first dimerize symmetrically through their HH domains, which then triggers U-box dimerization. This brings the extended helices into close proximity, including a repulsive stretch of positively charged residues. Unable to smoothly unwind, this conflict bends the helices until the helix of one protomer breaks to relieve the repulsion. The abrupt snapping of the helix forces the C-terminal residues of the other protomer to disrupt that protomer’s TPR-U-box tight binding interface, swiftly exposing and activating one of the E2 binding sites. Mutagenesis and biochemical experiments confirm that C-terminal residues are necessary both to maintain CHIP stability and function. This novel mechanism indicates how a ubiquitin ligase maintains an inactive monomeric form that rapidly activates only after asymmetric assembly.
Systematic evaluation for effects of urine pH on calcium oxalate crystallization, crystal-cell adhesion and internalization into renal tubular cells
Authors: Manissorn Juthatip , Fong-ngern Kedsarin , Peerapen Paleerath , Thongboonkerd Visith
Published: May 2017

Urine pH has been thought to be an important factor that can modulate kidney stone formation. Nevertheless, there was no systematic evaluation of such pH effect. Our present study thus addressed effects of differential urine pH (4.0–8.0) on calcium oxalate (CaOx) crystallization, crystal-cell adhesion, crystal internalization into renal tubular cells, and binding of apical membrane proteins to the crystals. Microscopic examination revealed that CaOx monohydrate (COM), the pathogenic form, was crystallized with greatest size, number and total mass at pH 4.0 and least crystallized at pH 8.0, whereas COD was crystallized with the vice versa order. Fourier-transform infrared (FT-IR) spectroscopy confirmed such morphological study. Crystal-cell adhesion assay showed the greatest degree of crystal-cell adhesion at the most acidic pH and least at the most basic pH. Crystal internalization assay using fluorescein isothiocyanate (FITC)-labelled crystals and flow cytometry demonstrated that crystal internalization into renal tubular cells was maximal at the neutral pH (7.0). Finally, there were no significant differences in binding capacity of the crystals to apical membrane proteins at different pH. We concluded that the acidic urine pH may promote CaOx kidney stone formation, whereas the basic urine pH (i.e. by alkalinization) may help to prevent CaOx kidney stone disease.
Enhanced sub-bandgap efficiency of a solid-state organic intermediate band solar cell using triplet–triplet annihilation
Authors: Lin YunHui L. , Koch Marius , Brigeman Alyssa N. , Freeman David M. E. , Zhao Lianfeng , Bronstein Hugo , Giebink Noel C. , Scholes Gregory D. , Rand Barry P.
Published: May 2017

A novel solid-state design is presented for an organic intermediate band solar cell with electrically integrated triplet–triplet annihilation upconversion.
Rotational spectra of tetracyclic quinolizidine alkaloids: does a water molecule flip sparteine?
Authors: Lesarri Alberto , Pinacho Ruth , Enríquez Lourdes , Rubio José E. , Jaraíz Martín , Abad José L. , Gigosos Marco A.
Published: May 2017

Flipping or not flipping? The sparteine–water dimer generated in a jet expansion retains thetransconformation of the parent molecule.
Structure–functionality relationship and pharmacological profiles of Pseudomonas aeruginosa alkylquinolone quorum sensing modulators
Authors: Kamal Ahmed A. M. , Petrera Lucia , Eberhard Jens , Hartmann Rolf W.
Published: May 2017

Alkylquinolone derived compounds revealed four pharmacological profiles for PqsR modulation. Molecular docking illuminated the structural requirements. Only inverse agonists were effective pathoblockers inhibiting pyocyanin.
Molecular mechanisms of Dicer: endonuclease and enzymatic activity
Authors: Song Min-Sun , Rossi John J.
Published: May 2017

The enzyme Dicer is best known for its role as a riboendonuclease in the small RNA pathway. In this canonical role, Dicer is a critical regulator of the biogenesis of microRNA and small interfering RNA, as well as a growing number of additional small RNAs derived from various sources. Emerging evidence demonstrates that Dicer's endonuclease role extends beyond the generation of small RNAs; it is also involved in processing additional endogenous and exogenous substrates, and is becoming increasingly implicated in regulating a variety of other cellular processes, outside of its endonuclease function. This review will describe the canonical and newly identified functions of Dicer.
Effect of Message Type on the Visual Attention of Adults With Traumatic Brain Injury
Authors: Thiessen Amber , Brown Jessica , Beukelman David , Hux Karen , Myers Angela
Published: May 2017

Purpose

The purpose of this investigation was to measure the effect of message type (i.e., action, naming) on the visual attention patterns of individuals with and without traumatic brain injury (TBI) when viewing grids composed of 3 types of images (i.e., icons, decontextualized photographs, and contextualized photographs).

Method

Fourteen adults with TBI and 14 without TBI—assigned either to an action or naming message condition—viewed grids composed of 3 different image types. Participants' task was to select/sustain visual fixation on the image they felt best represented a stated message (i.e., action or naming).

Results

With final fixation location serving as a proxy for selection, participants in the naming message condition selected decontextualized photographs significantly more often than the other 2 image types. Participants in the action message condition selected contextualized photographs significantly more frequently than the other 2 image types. Minimal differences were noted between participant groups.

Conclusions

This investigation provides preliminary evidence of the relationship between image and message type. Clinicians involved in the selection of images used for message representation should consider the message being represented when designing supports for people with TBI. Further research is necessary to fully understand the relationship between images and message type.
Secrecy outage analysis and power allocation for decode‐and‐forward relay systems
Authors: Qian Mujun , Liu Chen , Fu Youhua
Published: May 2017

The decode‐and‐forward multi‐relay system with the presence of an eavesdropper is researched in this study. Two widely used transmission schemes are considered, namely, the best‐relay selection scheme and the all‐relay‐based beamforming scheme. To be specific, the former scheme adopts only the single best relay among all the candidate relays that have succeeded in decoding the source signal to assist the transmission, whereas the all‐relay‐based beamforming scheme allows all the candidates to assist the source simultaneously in a beamforming manner. The authors reveal that in both schemes, if the total transmit power of the two hops is constrained, contradiction exists between the two means of improving physical‐layer security: (i) letting more relays succeed in decoding the source signal; (ii) increasing the transmit power of the selected relay(s). The authors thus analyse the secrecy outage behaviour of the two schemes and derive expressions of secrecy outage probability (SOP), based on which, the optimal power allocation solutions are obtained. It is demonstrated that in both schemes, the analysis results match well with the simulation results. Moreover, the proposed power allocation solutions surpass the conventional average power solution in SOP in both schemes.
Synthesis of 3-Formylbenzenesulfonyl Chloride Derivatives
Authors: Chen Guoliang , Bao Xuefei , Liu Ziao , Liang Xinjie , Song Dake , Shi Tao , Zhao Xuan , Bao Changshun
Published: May 2017

A synthetic route to 3-formylbenzenesulfonyl chloride derivatives from the corresponding benzaldehydes has been developed. The key step in this procedure is the conversion of aldehyde bisulfite adducts to target compounds via a two-stage reaction in the presence of Na2SO4. A series of 3-formylbenzenesulfonyl chloride derivatives were prepared by this method and identified by chemical derivatization method.
Management of early gastric cancer with positive horizontal or indeterminable margins after endoscopic submucosal dissection: multicenter survey
Authors: Ishii Naoki , Omata Fumio , Fujisaki Junko , Hirasawa Toshiaki , Kaise Mitsuru , Hoteya Shu , Tanabe Satoshi , Ishido Kenji , Ohata Ken , Takita Maiko , Mine Tetsuya , Igarashi Muneki , Yoshida Tatsuya , Takeda Yuichi , Furumoto Yohei , Matsumoto Kenshi , Yahagi Naohisa , Nakashima Hirotaka , Wada Tomonori , Tagata Tomoko , Mitsunaga Atsushi
Published: May 2017

Background and study aims Positive horizontal margins in resected specimens are sometimes encountered after endoscopic submucosal dissection (ESD) for early gastric cancers, and appropriate treatment strategies for these cases are not established. The aim of this study was to evaluate current empirical treatments for patients with positive horizontal or indeterminable margins after ESD.

Patients and methods We performed a multicenter survey and data from 14 hospitals were collected. The pooled proportions of positive horizontal or indeterminable margins and those of patients followed up without early intervention were calculated using a logistic-normal random-effects model. For calculating pooled estimates, subgroup analyses of high- and non-high-volume centers were conducted.

Results A total of 11,796 ESD cases were enrolled and 229 patients (2 %) had positive horizontal or indeterminable margins. Ninety-eight cases were treated within 30 days of ESD and 131 cases were followed up without early treatments. Pooled estimates of positive margins in high- and non-high-volume centers were 1 % (95 % CI: 1 % – 2 %) and 2 % (95 % CI: 1 % – 4 %), respectively, and were not heterogeneous (P = 0.191). The proportion of patients followed up without early intervention ranged from 30 % to 100 %. The pooled estimate was 68 % (95 % CI: 50 % – 83 %). The pooled estimates of high- and non-high-volume centers were 65 % (95 % CI: 38 % – 85 %) and 72 % (95 % CI: 44 % – 89 %), respectively, and were not heterogeneous (P = 0.692).

Conclusion There was insufficient consensus regarding treatment strategies used for early gastric cancer with positive horizontal or indeterminable margins after ESD. Further studies are required to establish a consensus.
Use of over-the-scope clips (OTSC) for hemostasis in gastrointestinal bleeding in patients under antithrombotic therapy
Authors: Lamberts Regina , Koch Anna , Binner Christian , Zachäus Marcus , Knigge Ingrid , Bernhardt Mark , Halm Ulrich
Published: May 2017

Background and study aims In patients taking different regimens of antithrombotic and/or anticoagulant therapy, endoscopic management of gastrointestinal bleeding represents a major challenge due to failing endogenous hemostasis. In this retrospective study we report on success rates with the over-the-scope clip (OTSC) system in upper and lower gastrointestinal bleeding in this high-risk patient population.

Patients and methods Between February 2011 and June 2014, 75 patients were treated with an OTSC for active gastrointestinal bleeding. Success rates with the first endoscopic therapy, rebleeding episodes, their management and the influence of antithrombotic or anticoagulant therapy were analyzed retrospectively.

Results Application of the OTSC resulted in immediate hemostasis (primary success rate) in all 75 patients. However, in 34.7 % a rebleeding episode was noted that could be treated by further endoscopic interventions. Only 3 patients had to be sent to the operating room because of failure of endoscopic therapy. In the rebleeding group the use of antiplatelet therapies was higher (73.1 % vs. 48.9 %).

Conclusions Application of the OTSC in GI bleeding results in a high rate of primary hemostasis. Rebleeding occurs in up to 35 % of patients receiving antithrombotic/anticoagulant therapy but can be managed successfully with further endoscopic treatments. Patients in the rebleeding group were more frequently treated with antiplatelet agents. Radiological or surgical therapy was reserved for a small subgroup not successfully managed by repeated endoscopic therapies. OTSC application is the treatment of choice in high-risk patients when conventional clips used as first-line treatment fail.
The chemical bond as an emergent phenomenon
Authors: Golden Jon C. , Ho Vinh , Lubchenko Vassiliy
Published: May 2017

We first argue that the covalent bond and the various closed-shell interactions can be thought of as symmetry broken versions of one and the same interaction, viz., the multi-center bond. We use specially chosen molecular units to show that the symmetry breaking is controlled by density and electronegativity variation. We show that the bond order changes with bond deformation but in a step-like fashion, regions of near constancy separated by electronic localization transitions. These will often cause displacive transitions as well so that the bond strength, order, and length are established self-consistently. We further argue on the inherent relation of the covalent, closed-shell, and multi-center interactions with ionic and metallic bonding. All of these interactions can be viewed as distinct sectors on a phase diagram with density and electronegativity variation as control variables; the ionic and covalent/secondary sectors are associated with on-site and bond-order charge density wave, respectively, the metallic sector with an electronic fluid. While displaying a contiguity at low densities, the metallic and ionic interactions represent distinct phases separated by discontinuous transitions at sufficiently high densities. Multi-center interactions emerge as a hybrid of the metallic and ionic bond that results from spatial coexistence of delocalized and localized electrons. In the present description, the issue of the stability of a compound is that of the mutual miscibility of electronic fluids with distinct degrees of electron localization, supra-atomic ordering in complex inorganic compounds coming about naturally. The notions of electronic localization advanced hereby suggest a high throughput, automated procedure for screening candidate compounds and structures with regard to stability, without the need for computationally costly geometric optimization.
Understanding the maximum dynamical heterogeneity during the unfreezing process in metallic glasses
Authors: Wang B. , Wang L. J. , Wang W. H. , Bai H. Y. , Gao X. Q. , Pan M. X. , Guan P. F.
Published: May 2017

The dynamic behaviors displayed during the unfreezing process of metallic glasses are investigated using molecular dynamics simulations. The non-monotonic variation of dynamical heterogeneity as temperature increases can be understood microscopically by the flow unit perspective. This variation of dynamical heterogeneity exhibits a peak at the temperature Tα2,max below the related α-relaxation temperature. Meanwhile, the Tα2,max signaling the maximum dynamical heterogeneity is found to be the onset temperature at which the largest activated cluster starts to present the percolation property. Our results give hints to the understanding of low temperature relaxation and the related correlation with α relaxation in metallic glasses.
Upper limit to the thermal penetration depth during modulated heating of multilayer thin films with pulsed and continuous wave lasers: A numerical study
Authors: Braun Jeffrey L. , Hopkins Patrick E.
Published: May 2017

In this study, we present a method to calculate the temperature and heat flux profiles as a function of depth and radius for bulk, homogeneous materials and samples with layered thin-film structures, including geometries supporting bidirectional heat fluxes, during pulsed and continuous wave (CW) laser heating. We calculate the temperature profiles for both modulated and unmodulated heating events to reveal that the thermal penetration depth (defined as the depth at which temperature decays to 1/e of the surface temperature) for a pulsed laser is highly dependent on time and repetition rate. In the high repetition rate limit, the temperature profile relaxes to that of a CW source profile, while in the opposite extreme, a single pulse response is observed such that the concept of the thermal penetration depth loses any practical meaning. For modulated heating events such as those used in time- and frequency-domain thermoreflectance, we show that there is a limit to the thermal penetration depth obtainable in an experiment, such that simple analytical expressions commonly used to determine thermal penetration depth break down. This effect is further compounded in samples with multiple layers, including the case when a ∼100 nm metallic transducer is deposited onto a bulk substrate, revealing that many recent studies relying on this estimation significantly over-predict the thermal penetration depth. Considering a bidirectional heat flow geometry (e.g., substrate/metal film/liquid), we find that heating from an unmodulated source results in an asymmetric heat flux about the plane of laser absorption to preserve a symmetric temperature profile when interfacial thermal resistance is negligible. However, the modulated case reveals a temperature asymmetry such that the thermal penetration depths in each side fall in line with those resulting from an insulated boundary condition.
Interfacial characteristics and multiferroic properties of ion-doped BiFeO3/NiFe2O4 thin films
Authors: Guo Meiyou , Tan Guoqiang , Zheng Yujuan , Liu Wenlong , Ren Huijun , Xia Ao
Published: May 2017

Multi-ion doped BiFeO3/NiFe2O4 bilayered thin films were successfully prepared on fluorine-doped SnO2/glass (SnO2:F) substrates by sol-gel method. The crystalline structure, leakage current, interfacial characteristics, and multiferroic properties were investigated in detail. The results of Rietveld refinement showed that the structure of BSrSFMC layer is transformed from rhombohedral to tetragonal structure by the means of ion-doping. The difference of leakage current density of the BSrSFMC/NiFe2O4 (NFO) bilayered films of the −40 V to 40 V and 40 V to −40 V are 0.32 × 10−5 and 1.13 × 10−5 A/cm2, respectively. It was observed that there are obvious interface effects between BSrSFMC and NFO layers, which will cause the accumulation of space charges and the establishment of built-in internal electric field (EI) at the interface. Therefore, different EI directions will affect the dipoles reversal and migration of carriers in the BSrSFMC layer, which will result in different values of transient current with the same applied voltage in the opposite directions. The larger coercive field (Ec ∼ 750 kV/cm) of BSrSFMC/NFO film indicated that there is a tensile stress at the interface between BSrSFMC and NFO layers, making the polarization difficult. These results showed that the above interesting phenomena of the J-V are closely related to the interface effects between the layer of BiFeO3 and NiFe2O4.
Polymorphs of Neutral Red, a Redox-Mediating Phenazine in Biological Systems
Authors: Labine-Romain Mackenzie , Beckmann Sabrina , Bhadbhade Mohan , Bhattacharyya Saroj , Manefield Michael , Marjo Christopher E. , Rich Anne M.
Published: April 2017

Neutral red 1 is a heterocyclic phenazine that, as a crystalline solid, has been observed to accelerate microbial methane generation from coal. Scale-up to an industrial process will require large quantities of neutral red crystals, hence an understanding of any polymorphic behaviour is essential for careful control of this process. A room-temperature structure of 1 (Form I) has been reported previously, and this study describes a new polymorph (Form II) crystallising from aqueous solution at 50°C, or transforming from Form I over an incubation time of one week at 70°C. Single-crystal X-ray diffraction has been used to study the molecular arrangements and intermolecular interactions in the new polymorph, and compared with those found in the room temperature form. Both polymorphs have been characterised using Raman and infrared spectroscopy, and a synthetic mixture of polymorphs successfully imaged using Raman spectroscopy. Raman imaging is proposed as a quality control method for small quantities of sample to ensure the correct polymorph is produced as a feedstock for this new methanogenesis process.
Sorption of selected radionuclides on different MnO2 phases
Authors: Athon Matthew T. , Fryxell Glen E. , Chuang Chia-Ying , Santschi Peter H.
Published: April 2017

Environmental contextReleases to the aquatic environment from radiological dispersal devices, accidents or leaking waste disposal sites require close monitoring for radionuclide identification. A novel in situ gamma spectrometer deployable on platforms in coastal waters can provide detailed radioisotopic, however, only after the radionuclides are pre-concentrated on efficient sorbents. Here, we report results of particle–water distribution coefficients, KD, on three novel MnO2 sorbents using a set of artificial and natural radionuclides in small batch experiments.
AbstractAfter nuclear disasters, there is a need to monitor released radionuclides in aquatic systems. A novel in situ gamma spectrometer deployable on mobile and stationary platforms can detect individual radionuclides, provided concentrations are high enough. Owing to rapid dilution effects, efficient sorbents are needed for preconcentration of radionuclides. Here, we report results of particle–water distribution coefficients, KD, on three novel MnO2 sorbents mounted in high-capacity cartridges using a set of artificial (57Co, 106Ru, 125Sb, 133Ba, 137Cs) and natural (7Be, 210Pb, 233Pa, 234Th) radionuclides in small batch experiments. Compared with conventionally impregnated MnO2 sorbents, novel nanostructured MnO2 sorbents displayed superior sorption for some artificial radionuclides, displaying up to one order of magnitude greater KD values than traditionally impregnated MnO2. In particular, the log KD value of 210Pb was highest (4.48±0.23) compared with all values using the other MnO2 sorbents, whereas that of 233Pa was among the lowest (3.24±0.16). These results promise some improvements for capturing not only artificially produced radionuclides, but also naturally produced 7Be from seawater using nanostructured MnO2. We also show that colloidal forms of selected radionuclides are not captured by MnO2 phases. If they could be sorbed by another sorbent, KD values could be considerably higher for Th, Po and other radionuclides. Finally, our results might add further complexities to the discussion of the potential of Th/Pa fractionation by MnO2 phases in seawater.
Is Knowledge Power? Information and Switching Costs in Agricultural Markets
Authors: Mitchell Tara
Published: April 2017

This article investigates an important channel through which access to information about market prices could increase the prices that producers receive from middlemen. I develop a model of trade between a farmer and a middleman, allowing for middlemen to differ in terms of their social preferences, and provide an empirical test of the theory using a framed field experiment carried out in India. The model predicts a non‐monotonic relationship between the benefit of information and the cost of switching to a new middleman. I find that actual middlemen do differ with regard to their social preferences, and that the benefit of information to the farmer varies with the cost of switching. While it is not possible to confirm a non‐monotonic relationship between the benefit of information and the cost of switching based on these data, the results are consistent with the predictions of the model.
Missing dust signature in the cosmic microwave background
Authors: Vavryčuk Václav
Published: May 2017

I examine a possible spectral distortion of the cosmic microwave background (CMB) due to its absorption by galactic and intergalactic dust. I show that even subtle intergalactic opacity of 1 × 10−7 mag h Gpc−1 at the CMB wavelengths in the local Universe causes non-negligible CMB absorption and decline of the CMB intensity because the opacity steeply increases with redshift. The CMB should be distorted even during the epoch of the Universe defined by redshifts z < 10. For this epoch, the maximum spectral distortion of the CMB is at least 20 × 10−22 W m−2 Hz−1 sr−1 at 300 GHz, which is well above the sensitivity of the COBE/FIRAS, WMAP or Planck flux measurements. If dust mass is considered to be redshift dependent with noticeable dust abundance at redshifts 2–4, the predicted CMB distortion would be even higher. The CMB would also be distorted in a perfectly transparent universe due to dust in galaxies, but this effect is lower by one order than that due to intergalactic opacity. The fact that the distortion of the CMB by dust is not observed is intriguing and questions either opacity and extinction law measurements or validity of the current model of the Universe.
Mindfulness-based Cognitive Therapy and Persistent Pain in Women Treated for Primary Breast Cancer
Authors: Johannsen Maja , O’Connor Maja , O’Toole Mia S. , Jensen Anders B. , Zachariae Robert
Published: May 2017

Objectives:

The aim of this study was to investigate possible statistical mediators in a randomized controlled trial of mindfulness-based cognitive therapy (MBCT) on pain intensity in women treated for primary breast cancer.

Materials and Methods:

The sample consisted of 129 women treated for breast cancer, presenting with persistent pain, who were randomly assigned to MBCT or a wait-list control. We previously reported a statistically significant and robust effect of MBCT on pain intensity (11-point numeric rating scale), which was included as the primary outcome. The proposed mediators were mindfulness (the Five Facet Mindfulness Questionnaire), self-compassion (the Short-Form Self-Compassion Scale), and pain catastrophizing (the Pain Catastrophizing Scale). Measurement points included baseline (T1), postintervention (T2), and 3- (T3) and 6-month (T4) follow-ups. All indirect effects of the mediators were tested in separate Multilevel Models, using the product-of-coefficients approach with bias-corrected confidence intervals (95% BSCI). The statistically significant mediators were then included in a multiple mediator model.

Results:

Statistically significant indirect effects were found for mindfulness nonreactivity (B=−0.17, BSCI [−0.32 to −0.04]) and pain catastrophizing (B=−0.76, BSCI [−1.25 to −0.47]). No statistically significant indirect effect was found for self-compassion (B=−0.09, BSCI [−0.30 to 0.04]). In a multiple mediator model, including mindfulness nonreactivity and pain catastrophizing, only pain catastrophizing remained statistically significant (B=−0.72, BSCI [−1.19 to −0.33]), explaining 78% of the effect.

Discussion:

The results of the present study may have clinical implications. An increased focus on the proposed mediators may optimize the clinical use of MBCT for persistent pain in women treated for breast cancer.
High Concentrations of Tranexamic Acid Inhibit Ionotropic Glutamate Receptors
Authors: Lecker Irene , Wang Dian-Shi , Kaneshwaran Kirusanthy , Mazer C. David , Orser Beverley A.
Published: May 2017

Background

The antifibrinolytic drug tranexamic acid is structurally similar to the amino acid glycine and may cause seizures and myoclonus by acting as a competitive antagonist of glycine receptors. Glycine is an obligatory co-agonist of the N-methyl-d-aspartate (NMDA) subtype of glutamate receptors. Thus, it is plausible that tranexamic acid inhibits NMDA receptors by acting as a competitive antagonist at the glycine binding site. The aim of this study was to determine whether tranexamic acid inhibits NMDA receptors, as well as α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid and kainate subtypes of ionotropic glutamate receptors.

Methods

Tranexamic acid modulation of NMDA, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid, and kainate receptors was studied using whole cell voltage-clamp recordings of current from cultured mouse hippocampal neurons.

Results

Tranexamic acid rapidly and reversibly inhibited NMDA receptors (half maximal inhibitory concentration = 241 ± 45 mM, mean ± SD; 95% CI, 200 to 281; n = 5) and shifted the glycine concentration–response curve for NMDA-evoked current to the right. Tranexamic acid also inhibited α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (half maximal inhibitory concentration = 231 ± 91 mM; 95% CI, 148 to 314; n = 5 to 6) and kainate receptors (half maximal inhibitory concentration = 90 ± 24 mM; 95% CI, 68 to 112; n = 5).

Conclusions

Tranexamic acid inhibits NMDA receptors likely by reducing the binding of the co-agonist glycine and also inhibits α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid and kainate receptors. Receptor blockade occurs at high millimolar concentrations of tranexamic acid, similar to the concentrations that occur after topical application to peripheral tissues. Glutamate receptors in tissues including bone, heart, and nerves play various physiologic roles, and tranexamic acid inhibition of these receptors may contribute to adverse drug effects.
Effects of Stimulus Duration on Event-Related Potentials Recorded From Cochlear-Implant Users
Authors: Presacco Alessandro , Innes-Brown Hamish , Goupell Matthew J. , Anderson Samira
Published: May 2017

Objectives:

Several studies have investigated the feasibility of using electrophysiology as an objective tool to efficiently map cochlear implants. A pervasive problem when measuring event-related potentials is the need to remove the direct-current (DC) artifact produced by the cochlear implant. Here, we describe how DC artifact removal can corrupt the response waveform and how the appropriate choice of stimulus duration may minimize this corruption.

Design:

Event-related potentials were recorded to a synthesized vowel /a/ with a 170- or 400-ms duration.

Results:

The P2 response, which occurs between 150 and 250 ms, was corrupted by the DC artifact removal algorithm for a 170-ms stimulus duration but was relatively uncorrupted for a 400-ms stimulus duration.

Conclusions:

To avoid response waveform corruption from DC artifact removal, one should choose a stimulus duration such that the offset of the stimulus does not temporally coincide with the specific peak of interest. While our data have been analyzed with only one specific algorithm, we argue that the length of the stimulus may be a critical factor for any DC artifact removal algorithm.
Palisaded Neutrophilic and Granulomatous Dermatitis/Interstitial Granulomatous Dermatitis Overlap: A Striking Clinical and Histologic Presentation With “Burning Rope Sign” and Subsequent Mirror-Image Contralateral Recurrence
Authors: Kern Malan , Shiver Mallory B. , Addis Kristen M. , Gardner Jerad M.
Published: May 2017

Palisaded neutrophilic and granulomatous dermatitis and interstitial granulomatous dermatitis are uncommon granulomatous dermatoses that often arise in association with rheumatoid arthritis. These 2 entities have overlapping features and may exist on a spectrum. We report an intriguing case of a 53-year-old man with advanced rheumatoid arthritis who presented with a large indurated painful truncal plaque with a palpable cord in addition to a papulonodular eruption on his dorsal hands. Furthermore, our patient had a recurrence in a near-identical mirror-image pattern on the contralateral trunk. The constellation of clinical and histopathological findings in our patient further suggests that palisaded neutrophilic and granulomatous dermatitis and interstitial granulomatous dermatitis exist as overlapping disease entities on a continuum. In addition, we propose that recurrence of skin findings may be indicative of the severity of the underlying systemic disease process.