bluuebunny/crossref_metadata_2025 huggingface dataset:
Poly(vinylidene fluoride) (PVDF)/potassium sodium niobate (KNN)–based nanofibrous web: A unique nanogenerator for renewable energy harvesting and investigating the role of KNN nanostructures
Authors: Teka Abebe , Bairagi Satyaranjan , Shahadat Md. , Joshi Mangala , Ziauddin Ahammad Sk. , Wazed Ali S.
Published: June 2018

In the recent era, finding renewable energy sources that are environmentally benign the main focus of scientific community around the globe. There is a plenty of renewable energy sources that are currently being researched such as solar power, thermal energy, wind energy, salinity gradients, and kinetic energy. Polymer‐ceramic–based nanocomposite piezoelectric material is known for quite some time for energy harvesting, but the real challenge lies as it requires very high loading of the ceramic part to obtain the required property and thus almost makes the system nonflexible. Developed material needs to be poled later on to use it as an electric energy generator from ambient mechanical movement. This current study is the first time attempt to produce a simple yet unique lightweight energy harvester using polyvinylidene fluoride (PVDF)/potassium sodium niobate (KNN) nanostructures–based nanocomposite flexible fibrous web where the material is in situ poled during its production using an electrospinning setup. At the beginning, various parameters were identified to synthesize and modulate KNN as nanostructural materials having higher aspect ratio, which is intended to provide a unique connection between KNN once these are embedded within the fibrous matrix. The incorporated KNN nanostructure having higher aspect ratio was also found to act as a beta nucleating agent in PVDF matrix and enhances the β‐phase crystal into the resultant fibrous web, which in turn increases the piezoelectric energy‐harvesting capacity manifold as compared with bare PVDF fibrous web. The in situ alignment of the nanostructured KNN (with a minimum loading, 5% only) into the fibrous nanocomposite is another achievement to obtain higher output. X‐ray diffraction and Fourier transform infrared analysis confirmed the mixture of α‐ and β‐crystalline phase of pure PVDF, which gets converted into β phase once KNN nanostructures are incorporated inside the nanofibrous web. An output voltage of 1.9 V was obtained from PVDF/KNN nanocomposite–based web, which is significantly higher (38 times) than generated voltage (50 mV) from the pure PVDF nanoweb without any subsequent poling operation.
Porous poly(vinyl formal) foam prepared using poly(vinyl alcohol) of low degree of polymerization
Authors: Li Yuanpeng , Deng Jianguo , Zhang Junhua
Published: June 2018

Poly(vinyl formal) (PVF) foams are usually prepared using poly(vinyl alcohol) (PVA) of high degree of polymerization, the most reported degree of polymerization being 1700. In the work reported, PVA of low degree of polymerization of 500 was used to prepare PVF foams, which is a great challenge because of the weaker hydrogen bond interaction than that for a higher degree of polymerization. By changing the concentration (from 10 to 20 wt%) of PVA solution, PVF foams were successfully obtained. It was found that a higher PVA concentration prevented foam volume shrinkage and the best concentration was 16 wt%. Scanning electron microscopy showed that the PVF foams had two kinds of pore structures, closed and open cell. The water absorption capacity and thermal properties of the PVF foams were carefully investigated. © 2018 Society of Chemical Industry
Diketopyrrolopyrrole‐based polymer fibrils formation by changing molecular conformation during film formation
Authors: Chen Liang , Zhao Kefeng , Cao Xinxiu , Liu Jiangang , Yu Xinhong , Han Yanchun
Published: June 2018

The microstructure of conjugated polymers film is strongly dependent on factors such as the conformation and the film formation processing. In this article, we show how to induce more planarization conformation of conjugated polymer backbone during film formation processing and finally leading to the fibrils formation of the cast film. The conjugated polymer we used is poly[[2,5‐bis(2‐octyldodecyl)‐2,3,5,6‐tetrahydro‐3,6‐dioxopyrrolo[3,4‐c]pyrrole‐1,4‐diyl]‐alt–[[2,2′‐(2,5‐thiophene)bis‐thieno[3,2‐b]thiophen]‐5,5′‐diyl]] (PDPPTT‐T). The main solvent is chloroform (CF), the aliphatic 1,8‐diiodooctane (DIO) is used as the additives, which has similar solubility parameter to the conjugated polymer side chain, is a bad solvent to the conjugated backbone and has a lower volatility than CF. Thus, during the film formation, chloroform was evaporated faster than the additive. After the chloroform evaporated completely, the side chain was still dissolved in the additive, which decreases the steric hindrance and improves planarization conformation of the conjugated backbone of PDPPTT‐T. Films processed using the aliphatic additives have fibrillar morphology while films cast from the CF solvent were featureless. TEM images reveal that the fibrils were about 30 nm in width and several hundred nanometers in length. The backbones of PDPPTT‐T were parallel to the long axis of fibrils. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2018, 56, 1079–1086
A Scalable Procedure for the Synthesis of BAMO
Authors: Azizi Ali Reza , Fakhraian Hossein , Karrabi Behzad
Published: June 2018

3,3‐bis(azidomethyl)oxetane (BAMO) homopolymer is used as binder in the formulation of some solid propellants. Herein, the synthesis of BAMO by two methods (three or two steps) has been reinvestigated following which, using pentaerythritol as a starting material, chlorination, oxetane ring formation and finally azidation of the produced oxetane have been performed. Following three steps method, the yield of the principal product of the first step (pentaerythritol trichloride) was increased by optimizing the reaction temperature, reaction time and proportional amount of the starting materials. The products of the first step were used in the second step without any further purification, using different amount of base and varying reaction time, affording 3,3‐bis(chloromethyl)oxethane (BCMO) as the principal product with increased yield. The reaction mixture of the second step was lead to the third step where, using excess amount of base and sodium azide, all the reactants coming from the first and second step (BCMO and other side products as pentaerythritol tetrachloride and 3‐chloromethyl‐3‐hydroxymethyl oxetane) were transformed to BAMO. Overall yield via three steps following optimized conditions was 60 % based on pentaerythritol. All products in each step were recognized by GC and GC‐MASS and BCMO and BAMO were also characterized by IR, 13C‐NMR and 1H‐NMR. In another attempt and following a two steps method, the products of the first step (chlorination of pentaerythritol) were used without any further purification in the second step where simultaneous usage of base and sodium azide (and conjoint formation of oxetane ring and its azidation) has afforded BAMO with an overall yield of 75 %.
Using MGD Gravitational Decoupling to Extend the Isotropic Solutions of Einstein Equations to the Anisotropical Domain
Authors: las Heras Camilo , León Pablo
Published: June 2018

The aim of this work is to obtain new analitical solutions for Einstein equations in the anisotropical domain. This will be done via the minimal geometric deformation (MGD) approach, that allow us to decouple the Einstein equations. It requires a perfect fluid known solution that we will choose to be Finch‐Skeas(FS) solution. Two different constraints were applied, and in each case we found an interval of values for the free parameters, where necesarly other physical solutions shall live.
Potential role for histone deacetylation in chronic diazepam‐induced downregulation of α1‐GABAA receptor subunit expression
Authors: Auta James , Gatta Eleonora , Davis John M. , Pandey Subhash C. , Guidotti Alessandro
Published: June 2018

Corroborating evidence indicate that the downregulation of GABAA receptor subunit expression may underlie tolerance to the anticonvulsant and anxiolytic actions of benzodiazepine (BZ) ligands that act as full allosteric modulators (FAMs) of GABA actions at a variety of GABAA receptor subtypes. We and others have shown that 10‐14 days treatment with increasing doses of diazepam (a FAM) resulted in anticonvulsant tolerance and decreased the expression of the α1 GABAA receptor subunit mRNA and protein in frontal cortex. In addition, we have also shown that long‐term treatment with imidazenil, a partial allosteric modulator of GABA action at selective GABAA receptor subtypes, fail to change the expression of the α1 subunit mRNA or induce tolerance to its anticonvulsant or anxiolytic action. However, little is known regarding the potential role of epigenetic mechanisms on long‐term BZ‐induced downregulation of GABAA receptor subunit. Therefore, we examined the role of histone acetylation and DNA methylation mechanisms on long‐term diazepam‐induced downregulation of the α1 subunit mRNA expression in rat frontal cortex. We found that 10 days treatment with increasing doses of diazepam but not imidazenil decreased the expression of the α1 GABAA receptor subunit mRNA and promoter acetylation in frontal cortex. In addition, we also found that 10 days treatment with diazepam but not imidazenil increased the expression of histone deacetylase (HDAC) 1 and 2 in frontal cortex. Thus, the increased expression of HDAC1 and HDAC2 (class 1 HDACs) and consequently increased histone deacetylation mechanism of this class 1 HDACs, may underlie long‐term diazepam‐induced decreased expression of the α1 GABAA receptor subunit mRNA in frontal cortex.
Polarimetric X‐band weather radars for quantitative precipitation estimation in mountainous regions
Authors: Yu Nan , Gaussiat Nicolas , Tabary Pierre
Published: June 2018

In order to minimize the economic and social impact of hazardous weather in the Alps, three X‐band dual‐polarization radars were deployed in the southeast of France during the RHYTMME project in 2011–2013 and more recently have been incorporated formally into the conventional radar network already operating S‐ and C‐band radars. In this mountainous region, the radars' beam shielding by the complex terrain, the very different altitudes of the radars, the significant attenuation at X‐band and the low density of rain‐gauges have made the integration of these radars into the operational service a challenging exercise. In this article, the framework used to evaluate the corrections applied to the volume data produced by the radars is presented and the residual errors related to the partial beam blockages, the attenuation by rain, the wet radome, and the melting layer are carefully studied and disentangled. The results of the analysis suggest that: (a) the beam blockage correction requires the use of a much higher resolution digital elevation model (DEM) in mountainous regions than the 250 m resolution DEM currently uses, (b) the dual‐pol reflectivity (Zh) attenuation correction used at Météo‐France performs well in the rain but the differential attenuation on Zdr is overestimated, (c) the attenuation of wet snow is underestimated and a mean error of 2 dB is induced by the melting layer in spring and autumn, (d) the wet radome, as well as producing significant attenuation on Zh, induces differential attenuation on Zdr. The attenuation in the melting layer is further investigated taking advantage of the height difference between the radar sites. A new specific attenuation coefficient for wet snow is suggested and it is shown to reduce the seasonal bias on three particular events observed in spring and autumn.
A Lagrangian vertical coordinate version of the ENDGame dynamical core. Part I: Formulation, remapping strategies, and robustness
Authors: Kavčič Iva , Thuburn John
Published: June 2018

Previous work provides evidence that Lagrangian conservation and related properties of a numerical model dynamical core can be improved by the use of a Lagrangian or quasi‐Lagrangian vertical coordinate (LVC). Most previous model developments based on this idea have made the hydrostatic approximation. Here the LVC is implemented in a non‐hydrostatic compressible Euler equation dynamical core using almost identical numerical methods to ENDGame, the operational dynamical core of the Met Office atmospheric Unified Model. This enables a clean comparison of LVC and height‐coordinate versions of the dynamical core using numerical methods that are as similar as possible. Since Lagrangian surfaces distort over time, model level heights are continually reset to certain “target levels” and the values of model fields are remapped onto their new locations. Different choices for these target levels are discussed, along with remapping strategies that focus on different conservation or balance properties. Sample results from a baroclinic instability test case are presented. The LVC formulation is found to be rather less robust than the height‐coordinate version; some reasons for this are discussed.
Rain attenuation statistics at Ka‐band estimated from weather radar observations in Belgium
Authors: Lukach Maryna , Quibus Laurent , Vanhoenacker‐Janvier Danielle , Delobbe Laurent
Published: June 2018

This paper presents rain attenuation statistics for satellite‐ground transmission links at Ka‐band based on 10‐year reflectivity observations from a C‐band weather radar. The ground receiving station and the radar are both located in Belgium. Only precipitation under the freezing level is considered, and the attenuation produced by hail is removed by applying a reflectivity threshold. The radar‐derived attenuations are analyzed to investigate the influence of elevation and azimuthal angles on the attenuation statistics. It is shown that the azimuthal dependence is extremely low. In contrast, the exceedance probability for a given attenuation threshold strongly increases with decreasing elevation angles, as foreseen by ITU‐R recommendations. The radar‐derived attenuations are used to estimate rain attenuation complementary cumulative distribution functions computed according to ITU‐R recommendations for a low Earth orbit satellite. The sensitivity to the hail reflectivity threshold is very limited. In contrast, our results show that reliable attenuation statistics cannot be obtained without taking carefully into account the height of the freezing level. Monthly averages of the freezing levels allow producing satisfactory results, but it is recommended to incorporate freezing level heights with high temporal and spatial resolutions.
Study on surface structure of plasma‐treated polydimethylsiloxane (PDMS) elastomer by slow positron beam
Authors: Wang Zheng , Luo Yi , Zheng Feng , Zhang Ni , Yin Chongshan , Li Jingjing , He Chunqing , Peng Xiangyang , Huang Zhen , Fang Pengfei
Published: June 2018

In this paper, the variations in surface structure of polydimethylsiloxane elastomers before and after argon plasma treatments have been investigated by X‐ray photoelectron spectroscopy, slow positron beam, and scanning electron microscope. An inorganic silica‐like layer was probed by X‐ray photoelectron spectroscopy after 3 minutes or longer time of treatments, and the sample surface turned into totally hydrophilic. Short time (1 and 2 min) plasma exposure mainly removed preexisting low molecular weighted (LMW) siloxanes on sample surface. By using slow positron beam, the thicknesses of silica‐like layer for 3‐, 5‐, and 10‐minute–treated samples were estimated to be around 30, 66, and 91 nm, respectively. Beneath the silica‐like layer, a loose polymeric structure was also detected, which was ascribed to the accumulation of LMW siloxanes. Scanning electron microscope images showed that the silica‐like layer cracked after 10 minutes of plasma treatment, which provided direct diffusion pathways for LMW siloxanes. Hence, 10‐minute–treated sample showed rather low organic composition near surface. Slow positron beam provides valuable depth profile information for evaluating the surface aging condition of polydimethylsiloxane composite.
Pyrimidine‐Pyrazole Hybrids as Morpholinopyrimidine‐Based Pyrazole Carboxamides: Synthesis, Characterisation, Docking, ADMET Study and Biological Evaluation
Authors: Vekariya Mayur K. , Vekariya Rajesh H. , Patel Kinjal D. , Raval Nirav P. , Shah Prapti U. , Rajani Dhanji P. , Shah Nisha K.
Published: June 2018

With the utilization of molecular hybridization, a series of novel morpholinopyrimidine based distinctive pyrazole carboxamides were designed and synthesized in an attempt to develop newer antimicrobial agents against the increasing bacterial resistance. Structure of final targeted compounds were confirmed by spectral analysis i. e. 1H‐NMR, 13C‐NMR and Mass spectra. The newly synthesized compounds were screened for their preliminary in‐vitro antibacterial activity against a panel of pathogenic strains of bacteria and fungi, antituberculosis activity against Mycobacterium tuberculosis H37Rv and antimalarial activity against Plasmodium falciparum. In addition to this, In‐silico molecular docking study and ADME properties were likewise studied for the targeted compounds. It was inferred that from the series, Fluorinated anilide derivatives of morpholinopyrimidine clubbed with pyrazole carboxylate emerged out as potential antimicrobial candidates from the in‐vitro antimicrobial assay.
Water Tetramer Confinement and Photosensitive Schottky Behavior of a 2D Coordination Polymer
Authors: Ahmed Faruk , Datta Joydeep , Sarkar Sirajuddin , Dutta Basudeb , Jana Atish Dipankar , Ray Partha Pratim , Mir Mohammad Hedayetullah
Published: June 2018

A mixed‐ligand divalent coordination polymer (CP) [Cu2(muco)2(py)4]⋅4H2O⋅2EtOH (1) has been synthesized by the reaction of Cu(ClO4)2⋅6H2O and pyridine (py) with trans, trans‐muconic acid (H2muco). The compound 1 has two‐dimensional (2D) sheet structure with approximately a square‐grid network containing one‐dimensional (1D) channels. Lattice water molecules are located in the void spaces and form discrete Z‐type water tetramer cluster. Interestingly, the compound 1 formed a Schottky interface with Al material which is supported from the impedance spectroscopy (IS) based network analysis. The photosensing parameters show that the material is well responsive to the illumination with sound detectivity power and rectification ratio. Therefore, this material has potential to be used as a Schottky diode as well as a photosensing device.
On the Relationship between the Chromium Concentration, the Z‐Phase Formation and the Creep Strength of Ferritic‐Martensitic Steels
Authors: Yu Hao , Xu Wei , van der Zwaag Sybrand
Published: June 2018

In this study, the long term creep strength behavior of commercial heat resistant martensitic/ferritic steels with Cr levels ranging from 1 to 15 wt% is analyzed by linking their computed equilibrium compositions to their creep properties. At lower Cr levels, the calculated strength due to precipitation hardening agrees well with the experimental results. At high chromium levels and longer exposure times, an accelerated strength loss due to the formation of Z‐phase precipitates has been reported. The accelerated strength loss is computationally analyzed and a correlation between accelerated strength loss and Z‐phase formation is confirmed. A study is made to explore the option of adjusting the chemical composition of existing high‐chromium steels to reduce the driving force for Z‐phase formation. However, no proper composition ranges are found which combine a high Cr concentration with a significantly lower driving force for Z‐phase formation.
Addressing the Barriers of Time
Authors: Morgan Denise N. , Bates Celeste C.
Published: June 2018

Teaching is a profession that requires ongoing professional development and learning. This ongoing learning can take place in professional learning communities, structured professional development settings, and literacy coaching contexts. This department highlights the ongoing professional development of literacy teachers.
RETRACTED: How reliable is fetal occiput and spine position assessment prior to induction of labor?
Authors: Kamel R. , Youssef A.
Published: June 2018

Objectives

To assess the reliability of fetal occiput and spine position determination in nulliparous women prior to induction of labor (IOL), and to evaluate identification of fetal occiput and spine positions prior to IOL in the prediction of labor outcome.

Methods

A series of 136 nulliparous women were recruited prospectively, immediately after the decision to perform IOL was made. Transabdominal ultrasound was performed to determine fetal head and spine positions. After at least 1 h, and prior to IOL, fetal occiput and spine positions were reassessed. Fetal occiput and spine positions were then compared between women who underwent vaginal delivery and those who delivered by Cesarean section.

Results

On the first and second assessments, respectively, fetal occiput position was anterior in 55 (40.4%) and 62 (45.6%) women, transverse in 52 (38.2%) and 49 (36.0%) women, and posterior in 29 (21.3%) and 25 (18.4%) women, while fetal spine position was anterior in 58 (42.6%) and 52 (38.2%) women, transverse in 42 (30.9%) and 50 (36.8%) women, and posterior in 36 (26.5%) and 34 (25.0%) women. Discordance between the first and second assessments of fetal occiput position was identified in 34 (25.0%) women, whereas discordance of fetal spine position was observed in 40 (29.4%) women. The incidence of fetal occiput posterior position in women undergoing Cesarean section was comparable to that in the vaginal‐delivery group (19 (18.8%) vs 6 (17.1%); P = 0.826), which was similarly the case for fetal posterior spine position (27 (26.7%) vs 7 (20%); P = 0.428). Women with fetal occiput posterior position had a longer induction‐to‐delivery interval in comparison to those with non‐occiput posterior fetal position (1786 ± 805 vs 1347 ± 784 min; P = 0.013).

Conclusions

Fetal occiput and spine positions are dynamic in a considerable proportion of women undergoing IOL, and their assessment does not seem to correlate with mode of delivery. Occiput and spine position assessment in women prior to IOL is unlikely to be clinically useful. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.
The all-loop conjecture for integrands of reggeon amplitudes in $$ \mathcal{N}=4 $$ SYM
Authors: Bolshov A. E. , Bork L. V. , Onishchenko A. I.
Published: June 2018

Abstract

In this paper we present the all-loop conjecture for integrands of Wilson line form factors, also known as reggeon amplitudes, in$$ \mathcal{N}=4 $$N=4SYM. In particular we present a new gluing operation in momentum twistor space used to obtain reggeon tree-level amplitudes and loop integrands starting from corresponding expressions for on-shell amplitudes. The introduced gluing procedure is used to derive the BCFW recursions both for tree-level reggeon amplitudes and their loop integrands. In addition we provide predictions for the reggeon loop integrands written in the basis of local integrals. As a check of the correctness of the gluing operation at loop level we derive the expression for LO BFKL kernel in$$ \mathcal{N}=4 $$N=4SYM.
Constraints on light Dark Matter fermions from relic density consideration and Tsallis statistics
Authors: Guha Atanu , Das Prasanta Kumar
Published: June 2018

Abstract

The cold dark matter fermions with mass MeV scale, pair produced inside the supernova SN1987A core, can freely stream away from the supernovae and hence contributes to its energy loss rate. Similar type of DM fermions (having similar kind of coupling to the standard model photon), produced from some other sources earlier, could have contributed to the relic density of the Universe. Working in a theory with an effective dark matter-photon coupling (inversely proportional to the scale Λ) in the formalism of Tsallis statistics, we find the dark matter contribution to the relic density and obtain a upper bound on Λ using the experimental bound on the relic density for cold non-baryonic matter i.e. Ωh
2 = 0.1186 ± 0.0020. The upper bound obtained from the relic density is shown with the lower bound obtained from the Raffelt’s criterion on the emissibity rate of the supernovae SN1987A energy loss

$$ \overset{\cdot }{\varepsilon}\left({e}^{+}{e}^{-}\to \chi \overline{\chi}\right)\le {10}^{19} $$

ε
⋅

e
+

e
−

→
χ

χ
¯

≤

10
19

erg g−1s−1 and the optical depth criteria on the free streaming of the dark matter fermion (produced inside the supernovae core). As the deformation parameter q changes from 1.0 (undeformed scenario) to 1.1 (deformed scenario), the relic density bound on Λ is found to vary from ∼ 4.9 × 107 TeV to 1.6 × 108 TeV for a fermion dark matter (χ) of mass m

χ
= 30 MeV, which is almost

10 times more than the lower bound obtained from the SN1987A energy loss rate and the optical depth criteria.
Quantizing the rotating string with massive endpoints
Authors: Sonnenschein Jacob , Weissman Dorin
Published: June 2018

Abstract

We compute leading order quantum corrections to the Regge trajectory of a rotating string with massive endpoints using semiclassical methods. We expand the bosonic string action around a classical rotating solution to quadratic order in the fluctuations and perform the canonical quantization of the resulting theory. For a rotating string in D dimensions the intercept receives contributions from D − 3 transverse modes and one mode in the plane of rotation, in addition to a contribution due to the Polchinski-Strominger term of the non-critical effective string action when D ≠ 26. The intercept at leading order is proportional to the expectation value of the worldsheet Hamiltonian of the fluctuations, and this is shown explicitly in several cases. All contributions to the intercept are considered, and we show a simple physical method to renormalize the divergences in them. The intercept converges to known results at the massless limit, and corrections from the masses are explicitly calculated at the long string limit. In the process we also determine the quantum spectrum of the string with massive endpoints, and analyze the asymmetric case of two different endpoint masses.
Clinical guidelines for primary sclerosing cholangitis 2017
Authors: Isayama Hiroyuki , Tazuma Susumu , Kokudo Norihiro , Tanaka Atsushi , Tsuyuguchi Toshio , Nakazawa Takahiro , Notohara Kenji , Mizuno Suguru , Akamatsu Nobuhisa , Serikawa Masahiro , Naitoh Itaru , Hirooka Yoshiki , Wakai Toshifumi , Itoi Takao , Ebata Tomoki , Okaniwa Shinji , Kamisawa Terumi , Kawashima Hiroki , Kanno Atsushi , Kubota Keiichi , Tabata Masami , Unno Michiaki , Takikawa Hajime ,   PSC guideline committee Members: Ministry of Health, Labour and Welfare (Japan) Research Project, The Intractable Hepatobiliary Disease Study Group
Published: June 2018

Background

Primary sclerosing cholangitis (PSC) is relatively rare disease and pathogenesis and methods of treatments were still not established. Then, we had conducted the making clinical guidelines to manage patients with PSC based on the literature review and expert opinions. These clinical guidelines were made for the medical doctors on the management of PSC, except child case of PSC.

Methods

We had employed modified Delphi method. The production committee decided guidelines, strength of recommendations and evidence level after reviewed literatures systematically, and The Expert panel evaluated those. The Scientific Committee of the Japan Biliary Association (JBA) evaluated revised guidelines, and the Public comments were collected on web site of JBA.

Results

We had made 16 guidelines about epidemiology/pathophysiology, diagnostics, therapy and prognosis. Also, we had made both diagnostic and therapeutic flow chart.

Conclusions

We hope that these guidelines will contribute to the improvement and development of the medical care of PSC.
Training Methods for Delivering Difficult News in Genetic Counseling and Genetics Residency Training Programs
Authors: Andoni Laila , Hobson Wendy L. , Carey John C. , Dent Karin M.
Published: June 2018

Genetic counselors and clinical geneticists are often in the position of delivering difficult news (DDN) to patients and families. Many studies show that healthcare providers require major improvement in the skills needed in DDN in a manner that is satisfactory to their patients. The purpose of this study was to assess the amount and methodology of DDN training received by genetic counselors and medical genetics residents in their training programs, such as observations of DDN or attending didactic lectures. To our knowledge, there is no previous assessment or study of DDN training in genetic counselor and medical genetics residency programs; therefore, we aim to both assess and compare the training in DDN received by genetic counselors and by genetics residents and determine whether there is a desire for recommendations on DDN training. We invited genetic counseling (GC) and genetics residency program directors to participate in an online survey designed to assess coursework, clinical experiences, and directors’ attitudes toward teaching DDN. Response rate was 85% (28/33) for GC program directors and 26% (14/53) for genetics residency program directors. One hundred percent of GC and genetics residency directors who responded to the survey agreed that it is important for genetic counselors and medical geneticists to be able to deliver difficult news effectively and that training programs should formally teach students how to deliver difficult news. Six of the eight common teaching methods are used by at least 75% of GC programs while two of eight are used by at least 75% of genetics residency programs. Seventy‐nine percent of GC and 93% of genetics residency program directors agree that there should be recommendations on how to teach students to deliver this news. Our results show that techniques for DDN are integrated more fully into GC program curricula than genetics residency curricula. Directors of both types of programs desire recommendations and more standardized education for training students to deliver difficult news.
Is Total Femur Replacement a Reliable Treatment Option for Patients With Metastatic Carcinoma of the Femur?
Authors: Sevelda Florian , Waldstein Wenzel , Panotopoulos Joannis , Kaider Alexandra , Funovics Philipp Theodor , Windhager Reinhard
Published: June 2018

Background

The majority of metastatic bone lesions to the femoral bone can be treated without surgery or with minimally invasive intramedullary nailing. In rare patients with extensive metastatic disease to the femur, total femur replacement may be the only surgical alternative to amputation; however, little is known about this approach.

Questions/purposes

In a highly selected small group of patients with metastatic carcinoma of the femur, we asked: (1) What was the patient survivorship after this treatment? (2) What was the implant survivorship free from all-cause revision and amputation, and what complications were associated with this treatment? (3) What functional outcomes were achieved by patients after total femur replacement for this indication?

Methods

Eleven patients (three men, eight women) with a mean age of 64 years (range, 41-78 years) received total femur replacements between 1986 and 2016; none were lost to followup. The most common primary disease was breast cancer. In general, during this period, our indications for this procedure were extensive metastatic disease precluding internal fixation or isolated proximal or distal femur replacement, and an anticipated lifespan exceeding 6 months. Our contraindication for this procedure during this time was expected lifespan less than 6 months. Patient survival was assessed by Kaplan-Meier analysis; implant survival free from revision surgery and amputation were assessed by competing risk analysis. Function was determined preoperatively and 6 to 12 weeks postoperatively with the Musculoskeletal Tumor Society (MSTS) score normalized to a 100-point scale, with higher scores representing better function from a longitudinally maintained institutional database.

Results

Eleven patients died at a median of 5 months (range, 1-31 months) after surgery. One-year revision-free and limb survival were 82% (95% CI, 51%-98%) and 91% (95% CI, 61%-99%), respectively. Reasons for reoperation were hip dislocation, infection and local recurrence in one patient each. The latter two complications resulted in amputation in two patients. The median MSTS score was 32 (range, 13-57).

Conclusions

Despite attempts to select patients who might have anticipated greater life expectancy, eight of 11 patients died by 6 months after surgery, and an additional two patients had undergone an amputation at 8 and at 17 months postoperatively. Most patients undergoing total femur replacement in this series did not recover from the procedure by the time they died, despite our best attempts to perform the procedure in patients whom we thought would live at least 6 months. Based on this, we believe that most patients with extensive metastatic disease to the femur should be offered palliative care, rather than major reconstruction.

Level of Evidence

Level IV, therapeutic study
Reduced-Order Microstructure-Sensitive Models for Damage Initiation in Two-Phase Composites
Authors: Montes de Oca Zapiain David , Popova Evdokia , Abdeljawad Fadi , Foulk James W. , Kalidindi Surya R. , Lim Hojun
Published: June 2018

Local features of the internal structure or the microstructure dominate the overall performance of materials. An open problem in materials design with enhanced properties is to accurately identify and quantify salient features of the microstructure and understand its correlation with the material’s performance. This task is exacerbated when dealing with failure related properties that show strong correlations to higher-order details of the material microstructure. This paper presents a novel data-driven framework for quantitatively determining the highly complex correlations that exist between the higher-order details of the material microstructure and its failure-related properties, specifically its damage initiation properties. The enclosed work will address this challenge by significantly extending the Materials Knowledge Systems (MKS) framework and by leveraging concepts in extreme value distributions and machine learning. The developed framework was capable of successfully sorting nine different classes of synthetically generated two-phase microstructures for their sensitivity to damage initiation. The framework and approaches presented here open new research avenues for studying the microstructure-sensitive damage initiation properties associated with heterogeneous materials, and pave the way forward for practical multiscale materials design.
Investigations of synthetic jet control effects on helicopter rotor in forward flight based on the CFD method
Authors: Zhao Q.-J. , Chen X. , Ma Y.-Yang , Zhao G.-Q.
Published: June 2018

To investigate the control effect of the synthetic jet on the aerodynamic characteristic of rotors, a numerical simulation procedure for the rotor flowfield is established. First, a moving-embedded grid method and an unsteady Reynolds Averaged Navier–Stokes (URANS) solver are established for predicting the complex flowfield of rotors. A velocity jet boundary condition over the jet actuator orifice is constructed, and a numerical method for simulating the active flow control on rotors is developed. Then, the effectiveness of the simulation method is validated by comparing the numerical results of jet control on NACA 0015 aerofoil with the experimental data. At last, the aerodynamic characteristic of rotors with synthetic jet actuators located on the suction surface of the blade in forward flight is calculated. The results indicate that the synthetic jet has the capability of improving the aerodynamic characteristic of rotors, especially in inhibiting the flow separation over the surface. In addition, the increase of the jet momentum coefficient and the jet angle can both enhance the lift coefficient in the retreating side. Compared with a single jet, jet arrays have better control effects on improving the aerodynamic characteristic of rotors in forward flight.
C.07 Calgary shunt protocol, an adaptation of the hydrocephalus clinical research network shunt protocol reduces risk of shunt infection in children
Authors: Yang M , Hader W , Bullivant K , Brindle M , Riva-Cambrin J
Published: June 2018

Background: The effectiveness of the Hydrocephalus Research Network (HCRN) shunt protocol has not been validated in a non-HCRN, small-to-medium volume pediatric neurosurgery center. This study evaluates whether the 9-step Calgary Shunt Protocol (CSP) adapted from the HCRN shunt protocol reduced shunt infections. Methods: The CSP was prospectively applied at Alberta Children’s Hospital from May 23rd, 2013 to all children undergoing any shunt procedure. Children undergoing shunt surgery before CSP implementation acted as a control-cohort. The strict HCRN definition of shunt infection was applied. Results: A total of 268 shunt procedures were performed. There was a significant absolute risk reduction of 10.0% ([95%CI 3.9%-15.9%], p=0.004) in shunt infections after implementation of the CSP. In univariate analyses, chlorhexidine compared to povidone skin prep reduced shunt infection by 8.2% ([95%CI 1.84-14.6%], p=0.02) and waiting ≥ 20 min between receiving preoperative antibiotics and skin incision reduced shunt infections by 9.6% ([95%CI 2.4%-16.9%], p=0.02). In multivariate analysis, only protocol implementation independently reduced shunt infections (OR 0.19 [95%CI 0.06-0.67], p=0.004). Conclusions: This study externally validates the published HCRN protocol for reducing shunt infection in an independent, non-HCRN, and small-to-medium volume neurosurgery setting. Chlorhexidine skin prep and waiting ≥ 20 min between preoperative antibiotic and skin incision may have contributed to the protocol’s quality improvement success.
P.008 Could Transient neurological Symptoms with subdural hematoma be explained by Cortical spreading depolarization Activity in Neurons? (CT-SCAN)
Authors: Levesque M , Deacon C , Bocti C , Moreau F , Vézina C , Iorio-Morin C
Published: June 2018

Background: Transient neurological symptoms in patients with subdural hematoma (SDH) are often attributed to secondary epilepsy despite a negative workup. We believe a significant proportion of these patients could rather suffer from cortical spreading depolarization (CSD). Methods: We performed a retrospective case-control study of patients with transient neurological symptoms post-SDH evacuation between 1996 and 2017. The clinical features of patients with negative EEG were compared to those with positive EEG (ictal or interictal abnormalities) and a clinical scoring system was created. Results: 59 patients were included, 20 (34%) with a positive EEG. Speech-related symptoms (OR 4.8, p=0.018) and prolonged episodes (OR 23.1, p=0.001) were associated with a negative EEG. Clonic movements (OR 0.014, p<0.0005), impaired awareness (OR 0.013, p<0.0005), positive symptoms (OR 0.05, p<0.0001), complete response to standard antiepileptic drugs (OR 0.06, p=0.007) and mortality (OR 0.021, p=0.003) were associated with a positive EEG. We built a clinical score based on these features, which showed a 90% sensitivity and 100% specificity. Conclusions: We believe that the differences observed between both groups were driven by the presence of CSD rather than seizure in the case group. Our proposed scoring system can help predict EEG results and may be useful to identify CSD in future trials.
P.009 Improving triaging of Infantile Spasm EEG referrals in a large Canadian institution
Authors: Djordjevic D , Go C
Published: June 2018

Background: Infantile spasms (IS) is a seizure disorder in young children which can be challenging to recognize. Early diagnosis and treatment of IS is critical for prevention of developmental delay. At the Hospital for Sick Children, rule-out IS accounts a large percentage of outpatient EEG referrals, while few result in a diagnosis. The goal of this study was to characterize the seizure semiology and source of referral, in order to explore ways in which triaging of these referrals may be improved. Methods: A retrospective review was done on all 84 rule-out IS EEG referrals within the last year at the Hospital for Sick Children. Source of referral, description of episodes, and result of EEG was extracted and data qualitatively analyzed. Results: Neurologists at Hospital for Sick Children accounted for the least number of referrals however contributed the greatest percentage of IS diagnoses. Non-neurologists contributed the most referrals, however 75% of these EEGs were normal. Common semiologies as described by referring physicians are discussed. Conclusions: Improved triaging of EEG referrals may be achieved through screening of referrals by paediatric neurologists, clarification of event semiology, and better IS education. This represents a critical opportunity for improvement of resource allocation as well as patient care and outcomes within all major referral centres.
P.027 Efficacy of a fourth alemtuzumab course in RRMS patients from CARE-MS II who experienced disease activity after three prior courses
Authors: Traboulsee A , Alroughani R , Boster A , Bass AD , Berkovich R , Fernández Ó , Kim H , Limmroth V , Lycke J , Macdonell RA , Singer BA , Vermersch P , Wiendl H , Ziemssen T , Melanson M , Daizadeh N , Comi G
Published: June 2018

Background: In RRMS patients with inadequate response to prior therapy, 2 alemtuzumab courses (12 mg/day; baseline: 5 days; 12 months later: 3 days) significantly improved outcomes versus SC IFNB-1a over 2 years (CARE-MS II [NCT00548405]). Efficacy remained durable in a 4-year extension (NCT00930553); patients could receive as-needed alemtuzumab retreatment (≥12 months apart) for disease activity, or another disease-modifying therapy (DMT). Through Year 6, 88% remained on study; 50% received neither alemtuzumab retreatment nor another DMT; 16% received ≥4 courses; 3% received ≥5 courses. We evaluated Course 4 (C4) efficacy in patients receiving ≥4 courses. Methods: Annualized relapse rate (ARR); improved/stable Expanded Disability Status Scale (EDSS) score (versus baseline); 6-month confirmed disability improvement (CDI). 11% of patients met inclusion criteria: ≥4 courses within 60 months of baseline; no DMT. Those receiving C5 were censored at that time. Results: ARR decreased after C4 (12 months pre-C4 [-12M]: 0.75; 12 months post-C4 [+12M]: 0.19; P<0.0001), remaining low (0.23) at Year 3 post-C4. More patients had stable/improved EDSS scores +12M (67.5%) versus at C4 administration (53.5%). Percentage with CDI increased post-C4 (-12M: 10.0%; +12M: 26.7%). Conclusions: C4 reduced relapses and stabilized/improved disability in patients with disease activity after initial treatment (C1, C2) plus one additional course (C3).
P.032 Cavernous sinus masses: An unusual case and review of the literature
Authors: Thorne MW
Published: June 2018

Background: We present a 67-year-old male with a two-week history of progressive double vision. Past medical history included oropharyngeal SCC, T4N2cM0, post-CCRT, and remote sarcoidosis. Clinically, the patient had multiple cranial nerve palsies affecting bilateral occular motor function. Neuroimaging showed an enhancing mass involving the sella and cavernous sinuses. Whole-body PET showed FDG-avid lesions in the sella and liver. Transsphenoidal biopsy of the sellar mass was obtained for tissue diagnosis. Methods: Details of the case were obtained from the patient’s EMR. Neuroimaging and neuropathology were reviewed with the appropriate subspecialists. A literature search was performed using multiple databases (PubMed, Web-of-Science) and relevant articles were included for review. Results: Sellar mass biopsy confirmed p16+ve SCC, identical to the patient’s known primary malignancy. On review of enhanced skull-base images, there was no evidence of direct tumor extension, favouring hematogenous spread. Conclusions: This case demonstrates the localizing potential of cavernous sinus masses. SCC metastases to the cavernous sinus are rare, and confer a poor prognosis.The presence of a p16 mutation has public health implications, as this mutation demonstrates more frequent and aggressive distant metastatic potential, and as a surrogate marker for high-risk HPV infection, represents a preventable risk-factor for a rapidly increasing cause of head and neck cancer in the Western world.
P.034 Supratentorial lateral ventricle hemangioblastoma in Von Hippel Lindau
Authors: Maroun FB , Galway B , Hache N , Stefanelli M , Engelbrecht A , Jacob JC
Published: June 2018

Background: Supratentorial ventricular hemangioblastoma (HB) associated with Von Hippel Lindau (VHL) are extremely rare. Due to their vascularity and location, their management can be difficult. Methods: A 35 year old female with VHL, has been followed for 25 years with multiple intracranial and spinal tumours. Surgical removal was carried out on one large cystic and solid posterior fossa lesion. In addition, she underwent adrenalectomy for pheochromocytoma. There were no pancreatic or renal lesions. On serial follow up for years, a left frontal ventricular lesion showed increasing size with clinical signs of increased ICP and marked hydrocephalus, requiring shunting procedures, which were carried out 11 years ago. She has been clinically stable since. Results: Hemangioblastomas of the CNS are rare and account for 2% of primary CNS tumours. Supratentorial location is estimated at 4% for sporadic and 13% for HB associated with VHL. The lateral ventricular location is extremely rare. Review of the literature revealed a total of 9 cases of supratentorial ventricular location. The majority of the lesions are associated with VHL and they are solid and vascular lesions. In our cases there was a cystic component. Conclusions: If removal is contemplated, angiography with possible preoperative embolization may be required.
P.039 In-hospital endocrinology consultation in post-operative pituitary surgery: is it necessary?
Authors: Clarke DB , Hebb AL , Massoud E , Imran S
Published: June 2018

Background: In-hospital Endocrinology consultation (IHEC) following transsphenoidal surgery is often routine but may be -unnecessary, lead to excessive blood testing, and prolong in-hospital stay. Purpose of this study: to determine whether the necessity of IHEC can be predicted by a standardized operative assessment tool. Methods: Retrospective review of all transsphenoidal surgeries from January 1, 2016, when we instituted an operative assessment tool to identify patients for which IHEC is required. Minimum follow-up: 3 months. Results: 78 patients (42 male; mean age: 57 yrs); the assessment tool identified 17 patients (22%) for IHEC and accurately identified those who would not require IHEC. IHEC patients had longer hospital stay (8.3 vs. 2.9 days), higher rate of new post-operative hormonal deficit (17.6% vs. 0%) and higher 30-day readmission rates (35% vs. 16%). Less than 10% had transient symptoms attributable to steroids; there were no long-term complications from routine post-operative steroid administration. Conclusions: Use of our operative assessment tool shows that at least three quarters of pituitary surgery patients can be managed safely without IHEC. Our data indicate that identifying these patients may reduce in-hospital stay and costs with no evidence of compromise of hormone-related care.