bluuebunny/crossref_metadata_2025 huggingface dataset:
Limited pollen dispersal, small genetic neighborhoods, and biparental inbreeding inVallisneria americana
Authors: Lloyd Michael W. , Tumas Hayley R. , Neel Maile C.
Published: March 2018

Premise of the Study

Pollen dispersal is a key process that influences ecological and evolutionary dynamics of plant populations by facilitating sexual reproduction and gene flow. Habitat loss and fragmentation have the potential to reduce pollen dispersal within and among habitat patches. We assessed aquatic pollen dispersal and mating system characteristics inVallisneria americana—a water‐pollinated plant with a distribution that has been reduced from historic levels.

Methods

We examined pollen neighborhood size, biparental inbreeding, and pollen dispersal, based on seed paternity using the indirect paternity method KinDist, from samples of 18–39 mothers and 14–20 progeny per mother from three sites across 2 years.

Key Results

On average, fruits contained seeds sired by seven fathers. We found significant biparental inbreeding and limited pollen dispersal distances (0.8–4.34 m). However, in a number of cases, correlated paternity did not decline with distance, and dispersal could not be reliably estimated.

Conclusions

Frequent pollen dispersal is not expected among patches, and even within patches, gene flow via pollen will be limited. Limited pollen dispersal establishes genetic neighborhoods, which, unless overcome by seed and propagule dispersal, will lead to genetic differentiation even in a continuous population. Unless loss and fragmentation drive populations to extreme sex bias, local pollen dispersal is likely to be unaffected by habitat loss and fragmentation per se because the spatial scale of patch isolation already exceeds pollen dispersal distances. Therefore, managing specifically for pollen connectivity is only relevant over very short distances.
T‐cell replete haploidentical stem cell transplantation attenuates the prognostic impact of FLT3‐ITD in acute myeloid leukemia: A report from the Acute Leukemia Working Party of the European Society for Blood and Marrow Transplantation
Authors: Canaani Jonathan , Labopin Myriam , Huang Xiao‐Jun , Arcese William , Ciceri Fabio , Blaise Didier , Irrera Giuseppe , Corral Lucia Lopez , Bruno Benedetto , Santarone Stella , Van Lint Maria Teresa , Vitek Antonin , Esteve Jordi , Mohty Mohamad , Nagler Arnon
Published: March 2018

Acute myeloid leukemia (AML) patients harboring the FLT3‐ITD mutation are considered a high risk patient subset preferentially allocated for allogeneic stem cell transplantation in first remission. Whether FLT3‐ITD retains a prognostic role in haploidentical stem cell transplantation (haplo‐SCT) is unknown. To analyze the prognostic impact of FLT3‐ITD in haplo‐SCT, we performed a retrospective analysis of the multicenter registry of the acute leukemia working party of the European Society for Blood and Marrow Transplantation. We included all adult AML patients with known FLT3 status who underwent a first T‐cell replete related haplo‐HCT in first complete remission from 2005 to 2016. We evaluated 293 patients of whom 202 were FLT3wt and 91 were FLT3‐ITD mutated. FLT3‐ITD patients were more likely to be NPM1 mutated as well as be in the intermediate risk cytogenetic risk category. In multivariate analysis, patients with FLT3‐ITD had comparable rates of relapse incidence [Hazard ratio (HR) = 1.34, confidence interval (CI) 95%, 0.67‐2.7; P = .9] and leukemia‐free survival (HR = 0.99, CI 95%, 0.62‐1.57; P = .9) to those of FLT3wt patients. Overall survival, the incidence of nonrelapse mortality, and graft versus host disease‐free/relapse‐free survival were not significantly impacted by FLT3‐ITD status. Furthermore, relapse and overall survival were comparable between FLT3‐ITD patients transplanted from various donor pools, namely matched siblings, unrelated donors, haplo‐SCT). Finally, subset analysis of patients with intermediate risk cytogenetics confirmed the absence of a prognostic impact of FLT3‐ITD also for this patient segment. In AML patients undergoing T‐cell replete haplo‐SCT, the FLT3‐ITD mutation possibly does not retain its prognostic significance.
Chemical Mapping by Macroscopic X‐ray Powder Diffraction (MA‐XRPD) of Van Gogh's Sunflowers: Identification of Areas with Higher Degradation Risk
Authors: Vanmeert Frederik , Hendriks Ella , Van der Snickt Geert , Monico Letizia , Dik Joris , Janssens Koen
Published: March 2018

The discoloration rate of chrome yellow (CY), a class of synthetic inorganic pigments (PbCr1−xSxO4) frequently used by Van Gogh and his contemporaries, strongly depends on its sulfate content and on its crystalline structure (either monoclinic or orthorhombic). Macroscopic X‐Ray powder diffraction imaging of selected areas on Van Gogh's Sunflowers (Van Gogh Museum, Amsterdam) revealed the presence of two subtypes of CY: the light‐fast monoclinic PbCrO4 (LF‐CY) and the light‐sensitive monoclinic PbCr1−xSxO4 (x≈0.5; LS‐CY). The latter was encountered in large parts of the painting (e.g., in the pale‐yellow background and the bright‐yellow petals, but also in the green stems and flower hearts), thus indicating their higher risk for past or future darkening. Overall, it is present in more than 50 % of the CY regions. Preferred orientation of LS‐CY allows observation of a significant ordering of the elongated crystallites along the direction of Van Gogh's brush strokes.
Shape‐Selective Zeolites Promote Ethylene Formation from Syngas via a Ketene Intermediate
Authors: Jiao Feng , Pan Xiulian , Gong Ke , Chen Yuxiang , Li Gen , Bao Xinhe
Published: March 2018

Syngas conversion by Fischer–Tropsch synthesis (FTS) is characterized by a wide distribution of hydrocarbon products ranging from one to a few carbon atoms. Reported here is that the product selectivity is effectively steered toward ethylene by employing the oxide‐zeolite (OX‐ZEO) catalyst concept with ZnCrOx‐mordenite (MOR). The selectivity of ethylene alone reaches as high as 73 % among other hydrocarbons at a 26 % CO conversion. This selectivity is significantly higher than those obtained in any other direct syngas conversion or the multistep process methanol‐to‐olefin conversion. This highly selective pathway is realized over the catalytic sites within the 8‐membered ring (8MR) side pockets of MOR via a ketene intermediate rather than methanol in the 8MR or 12MR channels. This study provides substantive evidence for a new type of syngas chemistry with ketene as the key reaction intermediate and enables extraordinary ethylene selectivity within the OX‐ZEO catalyst framework.
The Site‐Assembly Determines Catalytic Activity of Nanoparticles
Authors: Jørgensen Mikkel , Grönbeck Henrik
Published: March 2018

Heterogeneous catalysts are often designed as metal nanoparticles supported on oxide surfaces. Here, the relation between particle morphology and reaction kinetics is investigated by scaling relation kinetic Monte Carlo simulations using CO oxidation over Pt nanoparticles as a model reaction. We find that different particle morphologies result in vastly different catalytic activities. The activity is strongly affected by kinetic couplings between sites, and a wide site distribution generally enhances the activity. The present study highlights the role of site‐assemblies as a concept that, in addition to isolated active sites, can be used to understand catalytic reactions over nanoparticles.
SrB5O7F3 Functionalized with [B5O9F3]6− Chromophores: Accelerating the Rational Design of Deep‐Ultraviolet Nonlinear Optical Materials
Authors: Mutailipu Miriding , Zhang Min , Zhang Bingbing , Wang Liying , Yang Zhihua , Zhou Xin , Pan Shilie
Published: March 2018

Fluorooxoborates, benefiting from the large optical band gap, high anisotropy, and ever‐greater possibility to form non‐centrosymmetric structures activated by the large polarization of [BOxF4−x](x+1)− building blocks, have been considered as the new fertile fields for searching the ultraviolet (UV) and deep‐UV nonlinear optical (NLO) materials. Herein, we report the first asymmetric alkaline‐earth metal fluorooxoborate SrB5O7F3, which is rationally designed by taking the classic Sr2Be2B2O7 (SBBO) as a maternal structure. Its [B5O9F3]6− fundamental building block with near‐planar configuration composed by two edge‐sharing [B3O6F2]5− rings in SrB5O7F3 has not been reported in any other borates. Solid state 19F and 11B magic‐angle spinning NMR spectroscopy verifies the presence of covalent B−F bonds in SrB5O7F3. Property characterizations reveal that SrB5O7F3 possesses the optical properties required for deep‐UV NLO applications, which make SrB5O7F3 a promising crystal that could produce deep‐UV coherent light by the direct SHG process.
The effect of functional carbon nanotubes on the permeability of ultrafiltration nanocomposite PVDF membranes
Authors: Mofakhami Mehrabadi Mehran , Aghaei Alireza , Sahba Yaghmaee Maziar , Karimnezhad Masoud , Kamari Mosayyeb
Published: March 2018

Flux and antifouling performance of poly(vinylidnene fluoride) (PVDF) (15wt%.) nanocomposite ultrafiltration membrane with different functional carbon nanotubes (–COOH, –OH, –NH2) are considered. Membranes are prepared with phase‐inversion method using n‐methylpyrrolidone as solvent. This is the first time that hydrophilicity of different nanocomposite membranes are changing gradually, as performance of nanocomposite membrane are considered. Gradually changing of hydrophilicity explains behavior and performance of nanocomposite membrane. Scanning electron microscopy analysis of PVDF membrane with different functional multiwall carbon nanotube (FMWCNT) showed that all prepared membranes are asymmetric structure with a compact top layer and a bottom layer with large pore channels. All modified nanocomposite membranes show better hydrophilicity surface in compared with pristine PVDF membrane (87°). Results of pure water flux are approved by the result of contact angle and porosity. Measurement flux membranes with optimized percent FMWCNT is increased more than twofold compared to pristine membrane (146 L·m−2·hr−1). Atomic force microscopic also revealed that modified membranes have smaller roughness in compared with neat membrane (Sa = 270 nm). Flux recovery ratio analysis for all membranes is increased more than pure membrane (39%) because of better hydrophobicity and decrease of roughness. This subject is shown that FMWCNTs have no detrimental effect on mechanical resistance in modified membranes.
Polyhydroxyalkanoate coatings restrict moisture uptake and associated loss of barrier properties of thermoplastic starch films
Authors: Dilkes‐Hoffman Leela S. , Pratt Steven , Lant Paul A. , Levett Ian , Laycock Bronwyn
Published: March 2018

This work investigates the use of polyhydroxyalkanoate (PHA) films as moisture barriers for thermoplastic starch (TPS) films, to produce biodegradable, multi‐layer materials with high gas barrier properties. This is a necessary extension to the limited work available on this topic and confirms that PHAs are suitable coating materials for TPS films intended for use in food packaging. Under storage conditions of up to 75% relative humidity (RH) for 2 weeks, a PHA coating maintained the moisture content (MC) of the TPS below the point at which its barrier properties were detrimentally affected. Furthermore, for PHBV coating thicknesses of 91–115 μm, the MC of the TPS remains significantly lower than uncoated TPS for the duration of the experiment (>25 days). The flux of water into the coated TPS fit to a model based on Fick's law. However, when the multi‐layered films were stored at 95% RH delamination occurred within 24 h. Preliminary investigation into possible material design improvements showed that the addition of a small amount of PHA to the TPS layer prolonged the time to delamination. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46379.
A CD8α− Subset of CD4+SLAMF7+ Cytotoxic T Cells Is Expanded in Patients With IgG4‐Related Disease and Decreases Following Glucocorticoid Treatment
Authors: Della‐Torre Emanuel , Bozzalla‐Cassione Emanuele , Sciorati Clara , Ruggiero Eliana , Lanzillotta Marco , Bonfiglio Silvia , Mattoo Hamid , Perugino Cory A. , Bozzolo Enrica , Rovati Lucrezia , Arcidiacono Paolo Giorgio , Balzano Gianpaolo , Lazarevic Dejan , Bonini Chiara , Falconi Massimo , Stone John H. , Dagna Lorenzo , Pillai Shiv , Manfredi Angelo A.
Published: March 2018

Objective

An unconventional population of CD4+ signaling lymphocytic activation molecule family member 7–positive (SLAMF7+) cytotoxic effector memory T (TEM) cells (CD4+ cytotoxic T lymphocytes [CTLs]) has been linked causally to IgG4‐related disease (IgG4‐RD). Glucocorticoids represent the first‐line therapeutic approach in patients with IgG4‐RD, but their mechanism of action in this specific condition remains unknown. We undertook this study to determine the impact of glucocorticoids on CD4+ CTLs in IgG4‐RD.

Methods

Expression of CD8α, granzyme A, perforin, and SLAMF7 within the effector memory compartment of CD45RO+ (TEM) and CD45RA+ effector memory T (TEMRA) CD4+ cells was quantified by flow cytometry in 18 patients with active IgG4‐RD, both at baseline and after 6 months of glucocorticoid treatment. Eighteen healthy subjects were studied as controls. Next‐generation sequencing of the T cell receptor α‐ and β‐chain gene was performed on circulating CD4+ CTLs from patients with IgG4‐RD before and after treatment and in affected tissues.

Results

Circulating CD4+ TEM and TEMRA cells were not expanded in IgG4‐RD patients compared to healthy controls. CD4+SLAMF7+ TEM cells (but not TEMRA cells) were significantly increased among IgG4‐RD patients. Within CD4+SLAMF7+ TEM cells, CD8α− cells but not CD8αlow cells were elevated in IgG4‐RD patients. The same dominant clones of CD8α−CD4+SLAMF7+ TEM cells found in peripheral blood were also identified in affected tissue. CD8α− and CD8αlowCD4+SLAMF7+ TEM cells both expressed cytolytic molecules. Clonally expanded CD8α− but not CD8αlowCD4+SLAMF7+ TEM cells decreased following glucocorticoid‐induced disease remission.

Conclusion

A subset of CD8α−CD4+SLAMF7+ cytotoxic TEM cells is oligoclonally expanded in patients with active IgG4‐RD. This TEM cell population contracts following glucocorticoid‐induced remission. Further characterization of this cell population may provide prognostic information and targets for therapeutic intervention.
„Der erste zu sein.“[1] – Über den ersten Medizinnobelpreis für Emil von Behring im Jahr 1901
Authors: Enke Ulrike
Published: March 2018

“To be the first one.” – On the first Nobel Prize in Physiology or Medicine awarded to Emil von Behring in 1901. The German immunologist Emil von Behring (1854–1917) is the first Nobel Prize laureate in physiology or medicine. Behring received the award in 1901 “for his work on serum therapy, especially its application against diphtheria” (official prize motivation). Behring's name was strongly connected with progress in the field of diphtheria research through various publications. This study contextualizes the awarding of Behring and shows that not only significant scientific and practical results made him primus inter pares in the eyes of the Nobel committee, but also factors like Behring's representation in the daily press and the broad public interest in diphtheria research. After the beginning of the industrial serum production in 1894, Behring was not only a “visible scientist” (Massimiano Bucchi), he was also portrayed as the “savior of the children” and so ranked among the “great men” (Michael Gamper) of his era. The paper argues that his public visibility and the popularity of “Behring's Diphtherie‐Heilmittel” became a strong argument in favor of Behring during the selection process of the first Nobel laureate. The first part of the paper discusses the Nobel Prize nomination procedure from the views of the scientific community. Drawing on personal papers of the extended Behring Archives, the second part focusses on Behring from a private perspective and sheds light on the meaning and importance of the award for Behring and his family.
Hydrothermal growth of Zn2SnO4:Eu,Ca for red emission
Authors: Chembanthodi Kuttykrishnan Krishna Sagar , Mohammed Junaid Bushiri
Published: March 2018

Zinc stannate (Zn2SnO4) and Zn2SnO4 codoped with Eu3+ and Ca2+ (ZTO:Eu,Ca) were synthesized by hydrothermal method and characterized with X‐ray diffraction (XRD), energy‐dispersive X‐ray analysis (EDAX), Raman spectrometer, field emission scanning electron microscopy (FESEM), ultraviolet‐visible (UV‐vis) and photoluminescence (PL) spectrophotometers. PL analysis of Zn2SnO4 gives broad defect induced emission in the region 500–750 nm. The crystal structure of Zn2SnO4 was retained even with a nominal doping of Eu, Ca and its combination in the Zn2SnO4. The Eu3+ ions were found to occupy the non‐centrosymmetric sites of the Zn2SnO4 and gave emissions at 592, 615 and 702 nm. Zn2SnO4:Eu,Ca showed red emission at 615 nm attributed to the electronic transition from the excited state 5D0 → 7F2 of the 4f6 configuration of Eu3+. Nominal codoping of Eu3+ and Ca2+ ions promoted the quenching of orange emission from Eu3+ in Zn2SnO4:Eu,Ca.
Highly selective and sensitive coumarin–triazole‐based fluorometric ‘turn‐off’ sensor for detection of Pb2+ ions
Authors: Shaily  , Kumar Ajay , Parveen Iram , Ahmed Naseem
Published: March 2018

Exposure to even very low concentrations of Pb2+ is known to cause cardiovascular, neurological, developmental, and reproductive disorders, and affects children in particular more severely. Consequently, much effort has been dedicated to the development of colorimetric and fluorescent sensors that can selectively detect Pb2+ ions. Here, we describe the development of a triazole‐based fluorescent sensor L5 for Pb2+ ion detection. The fluorescence intensity of chemosensor L5 was selectively quenched by Pb2+ ions and a clear color change from colorless to yellow could be observed by the naked eye. Chemosensor L5 exhibited high sensitivity and selectivity towards Pb2+ ions in phosphate‐buffered solution [20 mM, 1:9 DMSO/H2O (v/v), pH 8.0] with a 1:1 binding stoichiometry, a detection limit of 1.9 nM and a 6.76 × 106 M−1 binding constant. Additionally, low‐cost and easy‐to‐prepare test strips impregnated with chemosensor L5 were also produced for efficient of Pb2+ detection and proved the practical use of this test.
Simultaneous determination of residues of thiamethoxam and its metabolite clothianidin in tobacco leaf and soil using liquid chromatography‐tandem mass spectrometry
Authors: Meng Banghua , Yu Yurong , Zhang Qingtao , Wang Shouyi , Hu Deyu , Zhang Kankan
Published: March 2018

A simple analytical method was developed to simultaneously determine thiamethoxam and its metabolite, clothianidin, in fresh tobacco leaf, soil and cured tobacco leaf using liquid chromatography with tandem mass spectrometry. Thiamethoxam and clothianidin in tobacco and soil samples were extracted with acetonitrile containing 0.1% formic acid and purified using an NH2‐SPE column. The optimized method provided good linearity with coefficients of determination R2 ≥ 0.9981. The limits of detection and quantification were between 0.006–0.12 and 0.02–0.4 mg/kg, respectively. Intra‐ and inter‐day recovery assays were used to validate the established method. The average recoveries of thiamethoxam and clothianidin in fresh tobacco leaf, soil and cured tobacco leaf were 75.04–100.47%, 75.86–86.40% and 89.83–99.39%, respectively. The intra‐ and inter‐day relative standard deviations were all <9%. The developed method was successfully applied for the analysis of thiamethoxam and clothianidin residues in actual tobacco and soil samples. The results indicated that the established method met the requirements for the analysis of trace amounts of thiamethoxam and clothianidin in fresh tobacco leaf, soil and cured tobacco leaf.
Threshold Flux for Vacuum Membrane Distillation to Concentrate Herbal Aqueous Solutions
Authors: Pan Linmei , Zhou Jing , Yang Chen , Zhu Huaxu
Published: March 2018

Vacuum membrane distillation (VMD) is considered an effective method for concentration of herbal aqueous solutions (HAS). However, membrane fouling and flux decline are complex problems in such concentration processes. The concept of threshold flux was proposed for optimizing the membrane process. Whether it is useful for guiding optimization of the VMD process on HAS concentration needs further investigation. The Semen Raphani aqueous solution (SRAS) was taken as an example to investigate the membrane flux behavior during SRAS concentration by VMD. The results confirmed that the threshold flux concept is applicable to concentrate HAS by VDM. At or below the threshold flux, the total resistance was independent of the flux, while above it membrane fouling increased with higher membrane flux. Moreover, limiting the flux should be avoided in the membrane process because of strong fouling and flux decline.
Increasing Porosity of Molded Calcium‐Based Sorbents by Glucose Templating for Cyclic CO2 Capture
Authors: Xu Yongqing , Ding Haoran , Luo Cong , Zheng Ying , Li Xiaoshan , Xu Yang , Zhang Zewu , Zhao Weixian , Zhang Liqi
Published: March 2018

With the aim to enhance the CO2 capture capacity and anti‐attrition property of CaO‐based sorbents simultaneously, a novel CaO‐based sphere was prepared by extrusion‐spheronization using Ca(OH)2 powder with glucose templating. The CO2 capture characteristics and attrition resistance property of the sorbent were examined and the microstructure of the sorbents was analyzed. The results demonstrate that the obtained spherical sorbents exhibit an outstanding anti‐attrition performance compared to limestone sorbent. After 100 cycles, all of the templated sorbents hold a CO2 capture capacity of more than one time higher than that of limestone. The optimum templating rate of glucose in the sorbent was 1–5 wt %.
A Capping Step During Automated Glycan Assembly Enables Access to Complex Glycans in High Yield
Authors: Yu Yang , Kononov Andrew , Delbianco Martina , Seeberger Peter H.
Published: March 2018

The products of multi‐step automated solid phase syntheses are purified after release from the resin. Capping of unreacted nucleophiles is commonplace in automated oligonucleotide synthesis to minimize accumulation of deletion sequences. To date, capping was not used routinely during automated glycan assembly (AGA) since previous capping protocols suffered from long reaction times and conditions incompatible with some protective groups. Here, a method using methanesulfonic acid and acetic anhydride for the fast and quantitative capping of hydroxyl groups that failed to be glycosylated is reported. Commonly used protective groups in AGA are stable under these capping conditions. The introduction of a capping step into the coupling cycle drastically improved overall yields by decreasing side‐products and simplifying purification, while reducing building block consumption. To illustrate the method, the biologically important tetrasaccharide Lc4, as well as a 50‐mer polymannoside were prepared.
Left hippocampal dosimetry correlates with visual and verbal memory outcomes in survivors of pediatric brain tumors
Authors: Zureick Andrew H. , Evans Casey L. , Niemierko Andrzej , Grieco Julie A. , Nichols Alexandra J. , Fullerton Barbara C. , Hess Clayton B. , Goebel Claire P. , Gallotto Sara L. , Weyman Elizabeth A. , Gaudet Dillon E. , Nartowicz Jessica A. , Ebb David H. , Jones Robin M. , MacDonald Shannon M. , Tarbell Nancy J. , Yock Torunn I. , Pulsifer Margaret B.
Published: March 2018

BACKGROUND

Radiotherapy (RT) in the pediatric brain tumor population causes late neurocognitive effects. In the current study, the authors investigated associations between clinical and dosimetric risk factors and memory outcomes in a cohort of patients treated with proton radiotherapy (PRT).

METHODS

A total of 70 patients (median age at PRT, 12.1 years [range, 5.0‐22.5 years]) who were treated with PRT were identified with baseline and follow‐up evaluations of visual and verbal memory (Children's Memory Scale and the third edition of the Wechsler Memory Scale). Whole‐brain as well as bilateral hippocampal and temporal lobe contours were delineated for the calculation of dosimetric indices. Multivariate analyses were performed to assess associations of score changes over time with clinical factors and dosimetric indices.

RESULTS

The median neurocognitive follow‐up was 3.0 years (range, 1.1‐11.4 years). For the entire cohort, delayed and immediate verbal memory scaled scores demonstrated small declines. The mean decline for delayed verbal memory scores was 0.6 (P = .01), and that for immediate verbal memory scores was 0.5 (P = .06). Immediate and delayed visual memory scores were not found to change significantly (+0.1 and ‐0.3, respectively; P>.30). A higher left hippocampal V20GyE (percentage of the volume of a particular anatomical region receiving at least a 20 gray equivalent) was correlated with a score decline in all 4 measures. Female sex was found to be predictive of lower delayed verbal memory follow‐up scores (P = .035).

CONCLUSIONS

Only delayed verbal memory scores were found to have declined statistically significantly at follow‐up after PRT, reflecting some weakness in verbal memory retrieval. Given a correlation of left hippocampal dosimetry and memory outcomes after PRT, left hippocampal‐sparing PRT plans may assist patients with pediatric brain tumors in preserving memory‐retrieval abilities. Cancer 2018;124:2238‐45. © 2018 American Cancer Society.
Substrate‐Induced Phase of a Benzothiophene Derivative Detected by Mid‐Infrared and Lattice Phonon Raman Spectroscopy
Authors: Schrode Benedikt , Jones Andrew O. F. , Resel Roland , Bedoya Natalia , Schennach Robert , Geerts Yves Henri , Ruzié Christian , Sferrazza Michele , Brillante Aldo , Salzillo Tommaso , Venuti Elisabetta
Published: March 2018

The presence of a substrate‐induced polymorph of 2,7‐dioctyloxy[1]benzothieno[3,2‐b]benzothiophene is probed in microscopic crystals and in thin films. Two experimental techniques are used: lattice phonon Raman and IR spectroscopy. The bulk crystal and substrate‐induced phase have an entirely different molecular packing, and therefore, their Raman spectra are characteristic fingerprints of the respective polymorphs. These spectra can be unambiguously assigned to the individual polymorphs. Drop‐cast and spin‐coated thin films on solid substrates are investigated in the as‐prepared state and after solvent‐vapor annealing. Because Raman spectroscopy is less sensitive with decreasing film thickness, IR spectroscopy is shown to be a more feasible tool for phase detection. The surface‐induced phase is mainly present in the as‐prepared thin films, whereas the bulk phase is present after solvent‐vapor annealing. This result suggests that the surface‐induced phase is a metastable polymorph.
Continuum kinetic modelling of cross‐separatrix plasma transport in a tokamak edge including self‐consistent electric fields
Authors: Dorf Mikhail , Dorr Milo
Published: March 2018

Eulerian kinetic calculations are presented for the axisymmetric cross‐separatrix plasma transport at the edge of a tokamak. The simulations are performed with a high‐order finite volume code COGENT, which solves the long‐wavelength limit of the full‐f ion gyrokinetic equation including the non‐linear Fokker–Plank collision model. Self‐consistent 2D electrostatic potential variations are obtained from the quasi‐neutrality (∇·j = 0) equation coupled to an isothermal fluid electron response. Illustrative solutions presented for parameters characteristic of the DIII‐D tokamak show qualitative agreement with experimental data.
UEDGE modelling of detached divertor operation for long‐leg divertor geometries in ARC
Authors: Wigram M. , LaBombard B. , Umansky M.V. , Kuang A.Q. , Brunner D. , Terry J.L. , Golfinopoulos T. , Rensink M.E. , Whyte D.G.
Published: March 2018

Simulations of the ARC scrape‐off layer and divertor configuration are carried out using UEDGE to perform the first power‐handling assessment for the divertor design. A convective–diffusive anomalous transport model is implemented in the code to reproduce the radial plasma profiles anticipated for the device at the outer mid‐plane. Levels of exhaust power from the core are varied, and a 0.5% fixed fraction neon impurity seeding is included in investigations to find steady‐state detached solutions. Initial studies employing a super‐X divertor configuration have shown that a stable detached divertor‐operational window exists for reactor exhaust powers in the range of 72–92 MW, which is close to projected levels of exhaust power of 105 MW across the separatrix anticipated for ARC. Under these conditions, the divertor heat flux is fully dissipated by radiation and radial losses to the sidewalls of the divertor channel, leading to acceptable levels of power flux density on plasma‐facing components. Simulations are being extended to study the performance of the X‐point target geometry and to explore the sensitivity to the physics model and input parameters.
Hybrid fluid–kinetic neutral model based on a kinetic correction on a fluid solution
Authors: Horsten N. , Samaey G. , Baelmans M.
Published: March 2018

We describe a hybrid fluid–kinetic approach for the neutral particles in the plasma edge for a simplified 1D model. This is done by means of a micro–macro decomposition of the kinetic equation. The closure terms from the fluid (macro) equations are modelled with a Monte Carlo (MC) simulation of the kinetic (micro) equation. We assess two hybrid neutral models with different underlying fluid models: (a) a pure pressure diffusion equation and (b) a pressure diffusion equation superposed with an energy equation. Both hybrid models reduce the statistical errors on the resulting particle and momentum sources by about a factor five for a given computational time, whereas the statistical error on the energy source is reduced by about a factor three compared to the full kinetic MC simulation. The hybrid model without the fluid energy equation slightly outperforms the model with the energy equation for the prediction of the particle and momentum sources, but adding an energy equation to the fluid model is beneficial for reducing the statistical error on the energy source.
Testing ontogenetic patterns of sexual size dimorphism against expectations of the expensive tissue hypothesis, an intraspecific example using oyster toadfish (Opsanus tau)
Authors: Dornburg Alex , Warren Dan L. , Zapfe Katerina L. , Morris Richard , Iglesias Teresa L. , Lamb April , Hogue Gabriela , Lukas Laura , Wong Richard
Published: March 2018

Trade‐offs associated with sexual size dimorphism (SSD) are well documented across the Tree of Life. However, studies of SSD often do not consider potential investment trade‐offs between metabolically expensive structures under sexual selection and other morphological modules. Based on the expectations of the expensive tissue hypothesis, investment in one metabolically expensive structure should come at the direct cost of investment in another. Here, we examine allometric trends in the ontogeny of oyster toadfish (Opsanus tau) to test whether investment in structures known to have been influenced by strong sexual selection conform to these expectations. Despite recovering clear changes in the ontogeny of a sexually selected trait between males and females, we find no evidence for predicted ontogenetic trade‐offs with metabolically expensive organs. Our results are part of a growing body of work demonstrating that increased investment in one structure does not necessarily drive a wholesale loss of mass in one or more organs.
Flood regimes driving vegetation and bird community transitions in semiarid floodplain woodlands
Authors: McGinness Heather M. , Arthur Anthony D. , Davies Micah
Published: March 2018

Water resource development in many parts of the world has resulted in serious reductions in the frequency, extent, and duration with which floodplain woodlands are inundated, resulting in significant habitat change and loss of productivity. Yet few studies have attempted to assess the effects of different flood regimes upon floodplain vegetation and fauna communities together, particularly during the terrestrial phase. We use new space‐for‐time substitution data from south‐eastern Australia to describe the nature of Eucalyptus largiflorens floodplain woodland communities under different flood regimes, from which inferences may be made about the consequences of water management decisions. We explore the hypothesis that differences in flood regime drive dissimilarities in vegetation structure and condition as well as variation in woodland bird abundance. Overall, insufficient flooding was associated with degradation of floodplain woodland condition and structure, as well as shifts in the relative abundance of key woodland bird groups. The results suggest that changes in flooding frequency are associated with significant shifts in site character and ultimately transitions in community composition, even within the same broad vegetation type. Importantly, these transitions are the result of interactions between water availability, vegetation changes, fauna habitat preferences, and interspecific interference competition. In addition, they indicate the influence of altered flood regimes upon terrestrial fauna of floodplain ecosystems rather than just aquatic components—a link that is relatively neglected by both scientists and managers to‐date. Such transitions and links have far‐reaching implications for ecosystem function at multiple scales and for how floodplains are understood, valued, and managed.
Effect of Residual Lithium Rearrangement on Ni‐rich Layered Oxide Cathodes for Lithium‐Ion Batteries
Authors: Park Jun‐Ho , Choi Byungjin , Kang Yoon‐Sok , Park Seong Yong , Yun Dong Jin , Park Insun , Shim Jae Ha , Park Jin‐Hwan , Han Heung Nam , Park Kwangjin
Published: March 2018

A water washing process can effectively reduce the presence of residual lithium with minimal effect on lithium‐ion battery cell performance. We investigated the effects of varying the amount of water used for washing and the temperature used to evaporate the water on Li1.00Ni0.80Co0.15Mn0.05O2. The residual lithium decreased and the cell performance deteriorated as the amount of water used for washing was increased from 0.7 to 5 times the amount of active material. The temperature at which the active material was dried after washing had a considerable effect on the reformation of the residual lithium layer after heat treatment. A ratio of water/active material of 1:1 and a drying temperature of 120 °C were selected as the optimal washing conditions, achieving a residual lithium content of less than 1000 ppm with minimum deterioration in cell performance; as a result of the treatment, the total volume of gas evolution was reduced by 25 %.
Development of a pendant experiment using melt indexer for correlation with the large‐size dripping in the UL‐94 test
Authors: Wang Yong , Kang Wendong , Zhang Xiaoyu , Chen Chao , Sun Peipei , Zhang Feng , Li Shaoxiang
Published: March 2018

The dripping phenomena affect fire hazards significantly. In the UL‐94 test, the dripping has been classified into the small‐size dripping due to surface melting and the large‐size dripping originating from bulk softening. Both types of dripping result from the gravity resisted by the forces including the viscous force. Based on the mechanical mechanism, a pendant experiment to reflect the ability of polymer melt to resist the gravity and a simple model equation were developed. The pendant experimental data of 7 polymers verified the model equation, and the regressed model parameter values of activation energy were close to reported data to some extent for most polymers. Correlations between the predicted pendant mass and the dripping behavior featured by the maximum drop mass showed that the pendant mass predicted at the glass transition temperature was proportional to the maximum drop mass. For polymers of large‐size dripping, the pendant mass predicted at typical decomposition temperatures such as the onset decomposition temperature was generally proportional to the maximum drop mass. Moreover, the model equation indicated that for the large‐size dripping the product of drop mass and first dripping time should be proportional to the specimen thickness, which was verified by reported dripping data.
Deep in the brain: Changes in subcortical function immediately preceding a migraine attack
Authors: Meylakh Noemi , Marciszewski Kasia K. , Di Pietro Flavia , Macefield Vaughan G. , Macey Paul M. , Henderson Luke A.
Published: March 2018

The neural mechanism responsible for migraine remains unclear. While the role of an external trigger in migraine initiation remains vigorously debated, it is generally assumed that migraineurs display altered brain function between attacks. This idea stems from relatively few brain imaging studies with even fewer studies exploring changes in the 24 h period immediately prior to a migraine attack. Using functional magnetic resonance imaging, we measured infra‐slow oscillatory activity, regional homogeneity, and connectivity strengths of resting activity in migraineurs directly before (n = 8), after (n = 11), and between migraine attacks (n = 26) and in healthy control subjects (n = 78). Comparisons between controls and each migraine group and between migraine groups were made for each of these measures. Directly prior to a migraine, increased infra‐slow oscillatory activity occurred in brainstem and hypothalamic regions that also display altered activity during a migraine itself, that is, the spinal trigeminal nucleus, dorsal pons, and hypothalamus. Furthermore, these midbrain and hypothalamic sites displayed increased connectivity strengths and regional homogeneity directly prior to a migraine. Remarkably, these resting oscillatory and connectivity changes did not occur directly after or between migraine attacks and were significantly different to control subjects. These data provide evidence of altered brainstem and hypothalamic function in the period immediately before a migraine and raise the prospect that such changes contribute to the expression of a migraine attack.
Impact of perioperative hyperglycemia in patients undergoing microvascular reconstruction
Authors: Bollig Craig A. , Spradling Claire S. , Dooley Laura M. , Galloway Tabitha L. , Jorgensen Jeffrey B.
Published: March 2018

Background

The effects of perioperative hyperglycemia on complications and outcomes in microvascular reconstruction have not been reported in the literature.

Methods

A retrospective cohort of 203 patients undergoing microvascular reconstruction was generated. Perioperative glucose levels and clinical factors were tested for associations with complications using simple and multivariate analyses.

Results

Hyperglycemia (blood glucose ≥ 180 mg/dL) occurred in 91 patients (44.8%) perioperatively, and was associated with increased rates of surgical complications, medical complications, surgical site infections, fistulas, and wound dehiscence. On univariate analysis, a more strict definition of hyperglycemia (blood glucose ≥ 165 mg/dL) was significantly associated with greater rates of venous thrombosis, although this lost statistical significance on multivariate analysis.

Conclusion

Perioperative hyperglycemia occurs commonly in patients undergoing microvascular reconstruction and is associated with higher rates of complications, independent of a preexisting diagnosis of diabetes mellitus. Further research is needed to define the ideal glycemic target in this population.
Prefer feeling bad? Subcultural differences in emotional preferences between Han Chinese and Mongolian Chinese
Authors: Deng Xinmei , Cheng Chen , Chow Hiu Mei , Ding Xuechen
Published: March 2018

As a multi‐ethnic country that is comprised of diverse cultural systems, there has been little research on the subcultural differences in emotional preferences in China. Also, little attention has been paid to examine how explicit and implicit attitudes towards emotions influence emotional preferences interactively. In this study, we manipulated explicit attitudes towards emotions among Han (N = 62) and Mongolian Chinese individuals (N = 70). We assessed participants' implicit attitudes towards emotions to explore their contributions to emotional preferences. (a) Han Chinese had lower preferences for pleasant emotions than Mongolian Chinese after inducing contra‐hedonic attitudes towards emotions, and (b) after priming contra‐hedonic attitudes towards emotions, the more Han Chinese participants evaluated pleasant emotions as negative implicitly, the less they preferred to engage in pleasant emotional activities. These findings contribute to the growing literature of subcultural differences and demonstrate that explicit and implicit attitudes towards emotions interactively influence individuals' emotional preferences between different subculture groups.
Scaffolding Critical Questions: Learning to Read the World in a Middle School Civics Class in Mexico
Authors: Gibson Melissa Leigh
Published: March 2018

This article shares the case of a student‐driven investigation into social issues from an eighth‐grade civics class at an American school in Mexico. Through vignettes about the teaching and learning process, the author argues that a focus on students’ inquiry into their social contexts rather than on specific social justice content is a key practice when teaching for critical democratic literacy, especially when teachers and students come from different social contexts. This article offers a concrete example of how foregrounding students’ critical questions can help move students toward social justice–oriented citizenship.
Wavelength‐dependent scattering in human eye with cataracts
Authors: Kelly‐Pérez Ismael , Méndez‐Aguilar Emilia M. , Treviño‐Palacios Carlos G. , Bruce Neil C. , Berriel‐Valdos Luis R. , Al‐Mohamedi Haroun , Bende Thomas
Published: March 2018

The gradual process in which the crystalline lens is cloudy due to the appearance of elements giving rise to variations in the refractive index is known as cataract. Clinical assessment is usually complicated because it considers patient's perception, and individuals with similar development have different visual deficits. This work presents a model which considers the fluctuations in the refractive index as spherical particles produce measurable scatter radial profiles patterns on the retina. Measurements for 2 different wavelengths simultaneously provide information on particle size and a quantitative assessment by measurement of the fluctuations of the refractive index.
High performance collision cross section calculation—HPCCS
Authors: Zanotto Leandro , Heerdt Gabriel , Souza Paulo C. T. , Araujo Guido , Skaf Munir S.
Published: March 2018

Since the commercial introduction of Ion Mobility coupled with Mass Spectrometry (IM‐MS) devices in 2003, a large number of research laboratories have embraced the technique. IM‐MS is a fairly rapid experiment used as a molecular separation tool and to obtain structural information. The interpretation of IM‐MS data is still challenging and relies heavily on theoretical calculations of the molecule's collision cross section (CCS) against a buffer gas. Here, a new software (HPCCS) is presented, which performs CCS calculations using high perfomance computing techniques. Based on the trajectory method, HPCCS can accurately calculate CCS for a great variety of molecules, ranging from small organic molecules to large protein complexes, using helium or nitrogen as buffer gas with considerable gains in computer time compared to publicly available codes under the same level of theory. HPCCS is available as free software under the Academic Use License at https://github.com/cepid-cces/hpccs. © 2018 Wiley Periodicals, Inc.
Discounting model selection with area‐based measures: A case for numerical integration
Authors: Gilroy Shawn P. , Hantula Donald A.
Published: March 2018

A novel method for analyzing delay discounting data is proposed. This newer metric, a model‐based Area Under Curve (AUC) combining approximate Bayesian model selection and numerical integration, was compared to the point‐based AUC methods developed by Myerson, Green, and Warusawitharana (2001) and extended by Borges, Kuang, Milhorn, and Yi (2016). Using data from computer simulation and a published study, comparisons of these methods indicated that a model‐based form of AUC offered a more consistent and statistically robust measurement of area than provided by using point‐based methods alone. Beyond providing a form of AUC directly from a discounting model, numerical integration methods permitted a general calculation in cases when the Effective Delay 50 (ED50) measure could not be calculated. This allowed discounting model selection to proceed in conditions where data are traditionally more challenging to model and measure, a situation where point‐based AUC methods are often enlisted. Results from simulation and existing data indicated that numerical integration methods extended both the area‐based interpretation of delay discounting as well as the discounting model selection approach. Limitations of point‐based AUC as a first‐line analysis of discounting and additional extensions of discounting model selection were also discussed.
Frontloading HIV financing maximizes the achievable impact of HIV prevention
Authors: Anderson Sarah‐Jane , Ghys Peter D , Ombam Regina , Hallett Timothy B
Published: March 2018

Introduction

Due to the nature of funding, national planners and international donors typically balance budgets over short time periods when designing HIV programmes (˜5‐year funding cycles). We aim to explicitly quantify the cost of short‐term funding arrangements on the success of future HIV prevention programmes.

Methods

Using mathematical models of HIV transmission in Kenya, we compare the impact of optimized combination prevention strategies under different constraints on investment over time. Each scenario has the same total budget for the 30‐year intervention period but the pattern of spending over time is allowed to vary. We look at the impact of programmes with decreasing, increasing or constant spending across 5‐year funding cycles for a 30‐year period. Interventions are optimized within each funding cycle such that strategies take a short‐term view of the epidemic. We compare these with two strategies with no spending pattern constraints: one with static intervention choices and another flexible strategy with interventions changed in year ten.

Results and Discussion

For the same total 30‐year budget, greatest impact is achieved if larger initial prevention spending is offset by later treatment savings which leads to accumulating benefits in reduced infections. The impact under funding cycle constraints is determined by the extent to which greater initial spending is permitted. Short‐term funding constraints and funds held back to later years may reduce impact by up to 18% relative to the flexible long‐term strategy.

Conclusions

Ensuring that funding arrangements are in place to support long‐term prevention strategies will make spending most impactful. Greater prevention spending now will bring considerable returns through reductions in new infections, greater population health and reductions in the burden on health services in the future.
The neuroprotective role of melatonin in neurological disorders
Authors: Alghamdi B. S.
Published: March 2018

Melatonin is a neurohormone secreted from the pineal gland and has a wide‐ranging regulatory and neuroprotective role. It has been reported that melatonin level is disturbed in some neurological conditions such as stroke, Alzheimer's disease, and Parkinson's disease, which indicates its involvement in the pathophysiology of these diseases. Its properties qualify it to be a promising potential therapeutic neuroprotective agent, with no side effects, for some neurological disorders. This review discusses and localizes the effect of melatonin in the pathophysiology of some diseases.