bluuebunny/crossref_metadata_2025 huggingface dataset:
Modelling Tools to Analyze and Assess the Ecological Impact of Hydropower Dams
Authors: Nguyen Thi , Everaert Gert , Boets Pieter , Forio Marie , Bennetsen Elina , Volk Martin , Hoang Thu , Goethals Peter
Published: March 2018

We critically analyzed a set of ecological models that are used to assess the impact of hydropower dams on water quality and habitat suitability for biological communities. After a literature search, we developed an integrated conceptual model that illustrates the linkages between the main input variables, model approaches, the output variables and biotic-abiotic interactions in the ecosystems related to hydropower dams. We found that variations in water flow and water depth coupled with increased nutrient availability are major variables that contribute to structural and functional ecosystem changes. We also found that ecological models are an important tool to assess the impact of hydropower dams. For instance, model simulation of different scenarios (e.g., with and without the dam, different operation methods) can analyze and predict the related ecosystem shifts. However, one of the remaining shortcomings of these models is the limited capacity to separate dam-related impacts from other anthropogenic influences (e.g., agriculture, urbanization). Moreover, collecting sufficient high-quality data to increase the statistical power remains a challenge. The severely altered conditions (e.g., generation of very deep lakes) also lead to difficulties for standardized data collection. We see future opportunities in the integration of models to improve the understanding of the different processes affected by hydropower dam development and operation, as well as the use of remote sensing methods for data collection.
miR-30c Impedes Glioblastoma Cell Proliferation and Migration by Targeting SOX9
Authors: Liu Shihui , Li Xiuxiu , Zhuang Sujing
Published: March 2018

miR-30c has been acknowledged as a tumor suppressor in various human cancers, such as ovarian cancer, gastric cancer, and prostate cancer. However, the role of miR-30c in glioblastoma (GBM) needs to be investigated. In our study, we found that the expression of miR-30c was significantly
downregulated in GBM tissues and cell lines. We found that overexpression of miR-30c inhibited cellular proliferation of GBM cells in vitro and in vivo. More GBM cells were arrested in the G0 phase after miR-30c overexpression. Moreover, we showed that miR-30c overexpression suppressed
the migration and invasion of GBM cells. Mechanistically, we found that SOX9 was a direct target of miR-30c in GBM cells. Overexpression of miR-30c inhibited the mRNA and protein levels of SOX9 in GBM cells. Moreover, there was a negative correlation between the expression of miR-30c and SOX9
in GBM tissues. Finally, we showed that restoration of SOX9 in GBM cells reversed the proliferation, migration, and invasion of GBM cells transfected with miR-30c mimic. Collectively, our results demonstrated that miR-30c suppressed the proliferation, migration, and invasion of GBM cells via
targeting SOX9.
Investigations towards the stereoselective organocatalyzed Michael addition of dimethyl malonate to a racemic nitroalkene: possible route to the 4-methylpregabalin core structure
Authors: Vargová Denisa , Baran Rastislav , Šebesta Radovan
Published: March 2018

Chiral derivatives of γ-aminobutyric acid are widely used as medicines and can be obtained by organocatalytic Michael additions. We show here the stereoselective synthesis of 4-methylpregabalin stereoisomers using a Michael addition of dimethyl malonate to a racemic nitroalkene. The key step of the synthesis operates as a kinetic resolution with a chiral squaramide catalyst. Furthermore, specific organocatalysts can provide respective stereoisomers of the key Michael adduct in up to 99:1 er.
WIYN Open Cluster Study. LXXVI. Li Evolution Among Stars of Low/Intermediate Mass: The Metal-deficient Open Cluster NGC 2506
Authors: Anthony-Twarog Barbara J. , Lee-Brown Donald B. , Deliyannis Constantine P. , Twarog Bruce A.
Published: March 2018

HYDRA spectra of 287 stars in the field of NGC 2506 from the turnoff through the giant branch are analyzed. With previous data, 22 are identified as probable binaries; 90 more are classified as potential non-members. Spectroscopic analyses of ∼60 red giants and slowly rotating turnoff stars using line equivalent widths and a neural network approach lead to [Fe/H] = −0.27 ± 0.07 (s.d.) and [Fe/H] = −0.27 ± 0.06 (s.d.), respectively. Li abundances are derived for 145 probable single-star members, 44 being upper limits. Among turnoff stars outside the Li-dip, A(Li) = 3.04 ± 0.16 (s.d.), with no trend with color, luminosity, or rotation speed. Evolving from the turnoff across the subgiant branch, there is a well-delineated decline to A(Li) ∼1.25 at the giant branch base, coupled with the rotational spindown from between ∼20 and 70 km s−1 to less than 20 km s−1 for stars entering the subgiant branch and beyond. A(Li) remains effectively constant from the giant branch base to the red giant clump level. A new member above the clump redefines the path of the first-ascent red giant branch; its Li is 0.6 dex below the first-ascent red giants. With one exception, all post-He-flash stars have upper limits to A(Li), at or below the level of the brightest first-ascent red giant. The patterns are in excellent qualitative agreement with the model predictions for low/intermediate-mass stars which undergo rotation-induced mixing at the turnoff and subgiant branch, first dredge-up, and thermohaline mixing beyond the red giant bump.
On the RR Lyrae Stars in Globulars. V. The Complete Near-infrared (JHKs) Census of ω Centauri RR Lyrae Variables*
Authors: Braga V. F. , Stetson P. B. , Bono G. , Dall’Ora M. , Ferraro I. , Fiorentino G. , Iannicola G. , Marconi M. , Marengo M. , Monson A. J. , Neeley J. , Persson S. E. , Beaton R. L. , Buonanno R. , Calamida A. , Castellani M. , Carlo E. Di , Fabrizio M. , Freedman W. L. , Inno L. , Madore B. F. , Magurno D. , Marchetti E. , Marinoni S. , Marrese P. , Matsunaga N. , Minniti D. , Monelli M. , Nonino M. , Piersimoni A. M. , Pietrinferni A. , Prada-Moroni P. , Pulone L. , Stellingwerf R. , Tognelli E. , Walker A. R. , Valenti E. , Zoccali M.
Published: March 2018

We present a new complete near-infrared (NIR, JHK

s
) census of RR Lyrae stars (RRLs) in the globular ω Cen (NGC 5139). We collected 15,472 JHK

s
images with 4–8 m class telescopes over 15 years (2000–2015) covering a sky area around the cluster center of 60 × 34 arcmin2. These images provided calibrated photometry for 182 out of the 198 cluster RRL candidates with 10 to 60 measurements per band. We also provide new homogeneous estimates of the photometric amplitude for 180 (J), 176 (H) and 174 (K

s
) RRLs. These data were supplemented with single-epoch JK

s
magnitudes from VHS and with single-epoch H magnitudes from 2MASS. Using proprietary optical and NIR data together with new optical light curves (ASAS-SN) we also updated pulsation periods for 59 candidate RRLs. As a whole, we provide JHK

s
magnitudes for 90 RRab (fundamentals), 103 RRc (first overtones) and one RRd (mixed-mode pulsator). We found that NIR/optical photometric amplitude ratios increase when moving from first overtone to fundamental and to long-period (P > 0.7 days) fundamental RRLs. Using predicted period–luminosity–metallicity relations, we derive a true distance modulus of 13.674 ± 0.008 ± 0.038 mag (statistical error and standard deviation of the median) based on spectroscopic iron abundances, and of 13.698 ± 0.004 ± 0.048 mag based on photometric iron abundances. We also found evidence of possible systematics at the 5%–10% level in the zero-point of the period–luminosity relations based on the five calibrating RRLs whose parallaxes had been determined with the HST.
The Effect of Weak Resistivity and Weak Thermal Diffusion on Short-wavelength Magnetic Buoyancy Instability
Authors: Gradzki Marek J. , Mizerski Krzysztof A.
Published: March 2018

Magnetic buoyancy instability in weakly resistive and thermally conductive plasma is an important mechanism of magnetic field expulsion in astrophysical systems. It is often invoked, e.g., in the context of the solar interior. Here, we revisit a problem introduc`ed by Gilman: the short-wavelength linear stability of a plane layer of compressible isothermal and weakly diffusive fluid permeated by a horizontal magnetic field of strength decreasing with height. In this physical setting, we investigate the effect of weak resistivity and weak thermal conductivity on the short-wavelength perturbations, localized in the vertical direction, and show that the presence of diffusion allows to establish the wavelength of the most unstable mode, undetermined in an ideal fluid. When diffusive effects are neglected, the perturbations are amplified at a rate that monotonically increases as the wavelength tends to zero. We demonstrate that, when the resistivity and thermal conduction are introduced, the wavelength of the most unstable perturbation is established and its scaling law with the diffusion parameters depends on gradients of the mean magnetic field, temperature, and density. Three main dynamical regimes are identified, with the wavelength of the most unstable mode scaling as either

or

or

, where d is the layer thickness and

is the ratio of the characteristic thermal diffusion velocity scale to the free-fall velocity. Our analytic results are backed up by a series of numerical solutions. The two-dimensional interchange modes are shown to dominate over three-dimensional ones when the magnetic field and/or temperature gradients are strong enough.
Chronic Hepatitis E in a Heart Transplant Patient: Sofosbuvir and Ribavirin Regimen Not Fully Effective
Authors: Todesco Eve , Mazzola Alessandra , Akhavan Sepideh , Abravanel Florence , Poynard Thierry , Roque-Afonso Anne-Marie , Peytavin Gilles , Marcelin Anne-Geneviève , Calmus Yvon , Lecuyer Lucien , Guillemain Romain , Conti Filomena
Published: March 2018

Hepatitis E virus (HEV) can induce chronic infections in the case of immunosuppression, which are sometimes not cured with ribavirin. Furthermore, sofosbuvir is a highly potent inhibitor of HCV polymerase and was shown to inhibit HEV genotype-3 replication in vitro. We report here the outcome of sofosbuvir/ribavirin therapy on a chronic HEV infection in a heart transplant recipient non-responder to ribavirin. After 24 weeks, the regimen failed to cure the persistent HEV infection, highlighting the need of therapeutic options for HEV-infected immunosuppressed patients.
HCV Genotype-3h, a Difficult-to-Diagnose Sub-Genotype in the DAA Era
Authors: Minichini Carmine , Starace Mario , De Pascalis Stefania , Macera Margherita , Occhiello Laura , Caroprese Mara , Vitrone Martina , Iovinella Vincenzo , Guerrera Barbara , Masarone Mario , Coppola Nicola
Published: March 2018

Background

No data are available on the clinical presentation and virological pattern in the case of failure of interferon (IFN)-free regimens in patients with genotype-3h. In this paper authors identified the virological and clinical characteristics of patients with genotype-3h treated with suboptimal or not indicated IFN-free regimens for the misclassification of HCV genotype.

Methods

A total of 87 consecutive patients with failure to an IFN-free regimen were re-tested for HCV genotype by HCV NS5B sequencing; the 26 patients identified as harbouring HCV-3 were enrolled.

Results

Of the 26 patients enrolled, 4 (15.4%) harboured sub-genotype-3h and 22 (84.6%) 3a. All patients were Italian. Patients with genotype-3a infection were younger (median age 56 years, range 47–78) compared to those with genotype-3h infection (median 74 years, range 65–79; P<0.006). With regard to the failed direct-acting antiviral (DAA)-regimens, three of the four patients with genotype-3h (75%) had been treated with an ineffective DAA regimen (paritaprevir, ombitasvir, dasabuvir ± ribavirin for 3 months) more frequently than those with genotype-3a (13.6%; P=0.02), because of previous erroneous identification of HCV-1 genotype. NS5A resistance-associated substitutions (RASs) were observed in 10 (45.4%) genotype-3a-infected patients and in 2 (50%) with genotype-3h. NS5B RASs were observed in only two genotype-3a-infected patients and in none of the 3h-infected patients.

Conclusions

This is the first time genotype-3h has been identified in Italian patients failing an IFN-free regimen, in the majority of cases because of a misclassification of the HCV genotype.
IDHM e a taxa de matrículas no ensino médio: uma análise multivariada dos maiores municípios que nomeiam as microrregiões do estado do Paraná
Authors: Grike Fabiane , Santos Gilson Ditzel , Oliveira Marlize Rubin
Published: March 2018

A educação no processo de desenvolvimento humano pode transformar e melhorar a maneira dos sujeitos se apropriarem da realidade na qual estão inseridos. A partir desse pressuposto este artigo teve por objetivo analisar a relação entre o Índice de Desenvolvimento Humano Municipal (IDHM) e as taxas de matrículas no Ensino Médio por habitante dos maiores municípios das microrregiões do estado do Paraná. Realizou-se uma pesquisa com caráter quantitativo a partir da técnica multivariada de agrupamentos e como base de dados foram utilizados os dados do IBGE/Atlas de Desenvolvimento Humano no Brasil (PNUD, 2013) e Censo Escolar/INEP (BRASIL, 2010). Foi possível verificar por meio das análises que a educação é uma forte aliada no desenvolvimento de uma determinada região, pois há diferença de uma microrregião geográfica para a outra em função do percentual de alunos matriculados no Ensino Médio.
Entrée en scène
Authors: Douplitzky Karine
Published: March 2018

Chacune des apparitions du divin enfant, aujourd’hui âgé de dix ans, est une liturgie, baptisée keynote . Leur enchaînement raconte une histoire sainte, un peu trop simple, celle d’Apple, dont Steve Job aura été l’évangéliste.
Du phone au scope
Authors: Sicard Monique
Published: March 2018

Nul n’avait anticipé les usages du smartphone. Le nom même de l’appareil témoigne de cette imprévision. Intelligent (smart) sans doute, mais si peu « téléphone », désormais. On fait bien d’autres choses avec un smartphone, à commencer par des selfies.
Le temps digital de l’entreprise
Authors: Malaval Catherine
Published: March 2018

Être « moderne », de nos jours, c’est être démodé. Ringardisé. Postmoderne ne vaut guère mieux. Comment alors une entreprise peut-elle être de son temps et même un peu en avance, et surtout durer ?
Le temps brisé
Authors: Debray Régis
Published: March 2018

Changement de siècle, changement de tempo. La mutation numérique, sensible dans nos façons de vivre et de sentir le présent, se reflète aussi dans notre appréhension du passé, comme en témoigne un ouvrage d’histoire à succès : L’Histoire mondiale de la France.
Les enseignements d’une comparaison manquée. Les professionnels de la participation en France et au Québec
Authors: Mazeaud Alice , Nonjon Magali
Published: March 2018

Cet article procède à une auto-analyse d’une expérience de comparaison manquée des professionnels de la participation en France et au Québec. Les difficultés rencontrées soulignent que les circulations croisées de dispositifs participatifs et d’acteurs entre ces deux espaces ne facilitent pas la comparaison. Au contraire, elles font obstacle à l’analyse en donnant l’illusion du partage d’un même univers de sens et de pratiques. À ce titre, elles rappellent que les catégories de l’analyse comparative ne sont jamais données. Elles sont à construire, à travers une comparaison compréhensive, sensible aux significations et aux institutions nationales. Une telle démarche semble ici d’autant plus cruciale à adopter que les chercheurs ne sont pas extérieurs à l’espace de la participation, ils en sont même des acteurs de premier plan. Aussi, même si l’objectif comparatif n’a pas été atteint, notre expérience s’est avérée particulièrement féconde pour mieux comprendre notre terrain français. Le passage par le Québec nous a permis de voir et d’interroger des éléments que nous ne percevions pas ou plus.
Predictors of Underrepresented Nursing Students' School Satisfaction, Success, and Future Education Intent
Authors: Williams Lovoria B. , Bourgault Annette B. , Valenti Michael , Howie Melissa , Mathur Sunil
Published: March 2018

Background:

The United States is steadily becoming more diverse. If current trends continue, the minority population will be the majority by 2043. In contrast to the U.S. population, nursing (the largest health care workforce) is composed of a nearly 76% White population. The literature reports that underrepresented minorities (URM) in nursing programs encounter multiple barriers to academic success.

Method:

A secondary data analysis of a national cohort of URM accelerated nursing students was conducted to examine three factors associated with microaggression—predictors of academic (NCLEX) success, satisfaction, and intent to pursue advanced education—among a cohort of URM accelerated nursing students who had received a national diversity scholarship (
n
= 2,250).

Results:

These three factors were predicted by institutional climate, mentoring, social interactions, the prematriculation preparation program, and other psychological, social, and cultural barriers.

Conclusion:

To increase nursing diversity and ensure a culturally competent profession, programs must attend to these factors. [
J Nurs. Educ.
2018;57(3):142–149.]
Using Critical Creativity to Reveal Nursing Student Learning in Long-Term Care
Authors: Indar Alyssa , Espin Sherry , LeGrow Karen , Janes Nadine
Published: March 2018

Background:

The use of teaching–learning strategies that emphasize critical reflection aids students in making sense of complex clinical placement settings, such as those in long-term care (LTC) settings.

Method:

A qualitative descriptive research design was used to explore the assumptions, anticipations, and realizations of six undergraduate nursing students regarding aging, gerontological nursing, and LTC as they engaged in facilitated critical reflection activities during a 12-week LTC placement.

Results:

The content analysis process revealed four main categories describing the student learning experience: Exploring the Therapeutic Nurse–Resident Relationship, Navigating Preceptor Relationships, Expanding Awareness of Context, and Embracing Many Feelings.

Conclusion:

Students placed in LTC were challenged by the realization of LTC as a complex setting, especially with minimal support from preceptors. Educators should present LTC as a challenging environment, rich with complex issues. There is potential in easing the strain on preceptors by leveraging the faculty educator role in facilitating student learning through critically creative approaches. [J Nurs Educ.2018;57(3):150–153.]
Association Rule Mining for Selecting Proper Students to Take Part in Proper Discipline Competition: A Case Study of Zhejiang University of Finance and Economics
Authors: Huang Xiaoling , Xu Yangbing , Zhang Shuai , Zhang Wenyu
Published: March 2018

In recent years, the educational issues have attracted more and more researchers’ and teachers’ attention. On the other hand, the development of data mining technology, provides a new method to extract the useful information from the complex educational data. In order to increase the chance of students to be awarded in discipline competition, it is better to select the proper students to take part in the proper discipline competition. Therefore, in this study, we collect the information of 164 undergraduate students as a case study. All students majored in Software Engineering in Zhejiang University of Finance and Economics. The Apriori algorithm with group strategy is used to find the relationship between the students’ courses scores and competition awards. According to the results of association rule mining, we find that the students with higher scores of C# Development, Object-Oriented, Internet Web Design, Data Structure(C#), and Basic Programming will have a higher probability to be awarded in the competition.
Exploring the Educational Potential of a Game-Based Math Competition
Authors: Kiili Kristian , Ojansuu Kai , Lindstedt Antero , Ninaus Manuel
Published: March 2018

The main aim of this article was to investigate the educational potential of a game-based math game competition to engage students in training rational numbers. Finnish fourth (n = 59; Mage = 10.36) and sixth graders (n = 105; Mage = 12.34) participated in a math game competition relying on intra-classroom cooperation and inter-classroom competition. During a three-week period, the students were allowed to play a digital rational number game, which is founded on number line estimation task mechanics. The results indicated that students benefited significantly from participating in the competition and playing behaviour could be used to assess students rational number knowledge. Moreover, students were engaged in the competition and the results revealed that intrinsically motivating factors such as enjoyment and perceived learning gains predicted students' willingness to participate in math game competitions again. This article provides empirical support that educational game competition can be an effective, engaging, and a fair instructional approach.
Geography Map Knowledge Acquisition by Solving a Jigsaw Map Compared to Self-Study
Authors: Dang Srishti , Ved Arunima , Vemuri Kavita
Published: March 2018

Efficacy of games as learning medium is of interest to researchers and the gaming industry. A critical metric for learning is knowledge retention and very few studies have conducted in-depth comparisons of: a) game versus no-game learning, b) collaborative versus individual learning. Towards this, the study reported in this article will present the findings from an experiment using Asia and world maps, cut into pieces as in a jigsaw puzzle. The participants were primary school children who were randomly assigned to the puzzle and no-puzzle group. To understand the role of collaborative interactions in learning, each group was further divided into two subgroups. Each subgroup either solved the puzzle or studied the full map (no-puzzle) individually or collaboratively. Three post-tests were conducted over a period of 10 days. The mean scores and Mann Whitney test shows: a) In the no-puzzle condition, no difference in the average scores of the individual and collaborative groups for both maps was observed, b) In the puzzle condition, the collaborative group score was slightly more than that of the individual group for Asia map, while the difference was significant for the continent map, and c) Puzzle and no-puzzle individual group scores were comparative for Asia map but the continent map groups showed a major difference. The findings are mixed with collaborative puzzle solving showing higher retention while puzzle solving does not show significant effect on learning and retention.
From iTE to NQT
Authors: Mac Mahon Brendan , Grádaigh Seán Ó , Ghuidhir Sinéad Ní
Published: March 2018

This article outlines a study to examine if newly qualified teachers (NQTs) who had incorporated iPad within pedagogical practice during initial teacher education, continued to do so in their first two years of teaching, and also to identify the challenges to integration that emerged. Findings show that use of iPad in teaching, learning and assessment by NQTs during induction year was followed by a significant fall in Year 2. Deeply embedded external barriers at both system and individual school context level are shown to exert significant influence on the use of iPad within pedagogical practice. It is concluded that NQTs require ongoing support to maintain and develop their practice with technology, and also that significant reform is required at senior cycle in Irish secondary schools to enable technology integration.
eTexts and Teacher Education
Authors: Schugar Jordan , Schugar Heather
Published: March 2018

This article describes how misunderstandings about eTexts may misguide educators when choosing how to incorporate eTexts into teaching and learning. A review of the existing literature finds that generalizations across different types and forms of eTexts and a reader's purpose and proficiency yield only more confusion. However, having a better understanding of the types of texts (both structure and purpose) operationalized in the studies as well as why these constructs impact eReading elucidate the potential benefits for more mobile reading pedagogy. Furthermore, the adoption of mobile pedagogies, as they relate to digital literacy, can occur on a programmatic scale, but requires a large-scale understanding of the interdisciplinary nature of the learning and/or reading task, technology, and discipline.
Robust Secured Roaming in Wireless Local Area Networks
Authors: Suntu Shaldon L. , Odongo Nickson H. , Chege Samwel M. , Bishoge Obadia K.
Published: March 2018

ABSTRACT
Effects of Rate-Controlled Sintering on Phase Formation, Dielectric and Ferroelectric Properties of Cobalt Oxide Doped BNKT Ceramics
Authors: Kruae-In Chatchai , Inthong Suchittra , Leenakul Wilaiwan
Published: March 2018

Lead-free powders of Bi(Na0.81K0.19)O3 doped 0.3 wt.% CoO were prepared by a conventional mixed oxide technique. The sintering process was controlled with various rate up and down temperature. The samples were sintered at 1,050 °C for 4 h which difference heating rate controlled i.e. 100, 300, and 600 °C/h. The XRD pattern analysis of all studied samples showed a single phase perovskite structure Dielectric and ferroelectric properties of the ceramics were investigated as a function of rate controlled sintering temperature. The sample heating rate at 600 °C/h showed maximum dielectric constant (~5961) at Tm. In addition, the ferroelectric properties were analyzed and discussed.
Ka Band RF Front-End Design
Authors: Mecidoglu Harun , Torpi Hamid
Published: March 2018

In this thesis, the RF front-end was done at K/Ka (18-27 GHz/26.5-40 GHz) bands used for satellite communication and satellite TV [1]. In this study, vertical polarized signal transmission and horizontal polarized signal reception were performed. The design is set to be compatible with TURKSAT 4B [2]. RF front-end is consist of an offset dish providing high gain and low side lobe level (SLL) for collecting the signal, a circular horn antenna which is compatible with RHCP (Right Hand Circular Polarization) and LHCP (Left Hand Circular Polarization) polarizations at the focal point of the dish, to separate dual polarization an orthomode transducer (OMT) and a transmit reject filter to prevent the receiver from the strong signal generated at the transmitter side (cross-pol). In the design waveguide structures is used to work in microwave frequencies and for high power delivery requirements. AWR Microwave Office, Computer Simulation Technology (CST) and MATLAB (Matrix Laboratory) programs are used for simulation, optimization and calculations.
Spontaneous Adhesion of DOPA and Tryptophan Functionalized PEG to Polystyrene Nanobeads: An EPR Study
Authors: Göksel Yaman , Kırpat İklima , Akdogan Yasar
Published: March 2018

Wet adhesion is achieved by mussels so naturally. Their adhesion mechanism has inspired scientists to obtain wet adhesives for a long time. The amino acid 3,4-dihydroxyphenylalanine (DOPA) produced by mussels adheres to different types of surfaces and also contributes to cohesive interactions. Here, we showed the spontaneous adhesion of DOPA functionalized four armed poly (ethylene glycol) (PEG) polymer to spin labeled polystyrene (SL-PS) nanosurfaces by electron paramagnetic resonance (EPR) spectroscopy. In addition to DOPA, adhesion property of another amino acid of tryptophan (Trp) was studied. Trp attached four armed PEG polymers did not adhere to the surface of SL-PS in the force free condition. However, two armed DOPA and two armed Trp functionalized PEG adhere to the PS.
HTSC Bulk Magnetizing Control System for Cryogenic Alternators
Authors: Chubraeva Lidia , Evseev Eugeniy , Timofeev Sergey
Published: March 2018

The first HTSC alternators developed and tested mainly contained the bulks on the rotor. The presentation covers the problem of HTSC bulks magnetizing control in an assembled cryogenic alternator with axial flux. Cylindrical bulks are positioned on the rotor of a synchronous machine and form a multi-pole excitation system. The trapped magnetic field may vary under a number of processes, magnetic flux creep included. A special system to control the value of bulk magnetization and the temperature in the cryogenic zone is developed. Similar system may by applied in cryogenic disc-type alternators with permanent magnets on the rotor.
The Immunogenicity of a Proline-Substituted Altered Peptide Ligand toward the Cancer-Associated TEIPP Neoepitope Trh4 Is Unrelated to Complex Stability
Authors: Hafstrand Ida , Doorduijn Elien M. , Sun Renhua , Talyzina Anna , Sluijter Marjolein , Pellegrino Sara , Sandalova Tatyana , Duru Adil Doganay , van Hall Thorbald , Achour Adnane
Published: March 2018

Human cancers frequently display defects in Ag processing and presentation allowing for immune evasion, and they therefore constitute a significant challenge for T cell–based immunotherapy. We have previously demonstrated that the antigenicity of tumor-associated Ags can be significantly enhanced through unconventional residue modifications as a novel tool for MHC class I (MHC-I)–based immunotherapy approaches. We have also previously identified a novel category of cancer neo-epitopes, that is, T cell epitopes associated with impaired peptide processing (TEIPP), that are selectively presented by MHC-I on cells lacking the peptide transporter TAP. In this study, we demonstrate that substitution of the nonanchoring position 3 into a proline residue of the first identified TEIPP peptide, the murine Trh4, results in significantly enhanced recognition by antitumor CTLs toward the wild-type epitope. Although higher immunogenicity has in most cases been associated with increased MHC/peptide complex stability, our results demonstrate that the overall stability of H-2Db in complex with the highly immunogenic altered peptide ligand Trh4-p3P is significantly reduced compared with wild-type H-2Db/Trh4. Comparison of the crystal structures of the H-2Db/Trh4-p3P and H-2Db/Trh4 complexes revealed that the conformation of the nonconventional methionine anchor residue p5M is altered, deleting its capacity to form adequate sulfur–π interactions with H-2Db residues, thus reducing the overall longevity of the complex. Collectively, our results indicate that vaccination with Thr4-p3P significantly enhances T cell recognition of targets presenting the wild-type TEIPP epitope and that higher immunogenicity is not necessarily directly related to MHC/peptide complex stability, opening for the possibility to design novel peptide vaccines with reduced MHC/peptide complex stability.
Associations of Simian Immunodeficiency Virus (SIV)-Specific Follicular CD8+ T Cells with Other Follicular T Cells Suggest Complex Contributions to SIV Viremia Control
Authors: Rahman Mohammad Arif , McKinnon Katherine M. , Karpova Tatiana S. , Ball David A. , Venzon David J. , Fan Wenjin , Kang Guobin , Li Qingsheng , Robert-Guroff Marjorie
Published: March 2018

Follicular CD8+ T (fCD8) cells reside within B cell follicles and are thought to be immune-privileged sites of HIV/SIV infection. We have observed comparable levels of fCD8 cells between chronically SIV-infected rhesus macaques with low viral loads (LVL) and high viral loads (HVL), raising the question concerning their contribution to viremia control. In this study, we sought to clarify the role of SIV-specific fCD8 cells in lymph nodes during the course of SIV infection in rhesus macaques. We observed that fCD8 cells, T follicular helper (Tfh) cells, and T follicular regulatory cells (Tfreg) were all elevated in chronic SIV infection. fCD8 cells of LVL animals tended to express more Gag-specific granzyme B and exhibited significantly greater killing than did HVL animals, and their cell frequencies were negatively correlated with viremia, suggesting a role in viremia control. Env- and Gag-specific IL-21+ Tfh of LVL but not HVL macaques negatively correlated with viral load, suggesting better provision of T cell help to fCD8 cells. Tfreg positively correlated with fCD8 cells in LVL animals and negatively correlated with viremia, suggesting a potential benefit of Tfreg via suppression of chronic inflammation. In contrast, in HVL macaques, Tfreg and fCD8 cell frequencies tended to be negatively correlated, and a positive correlation was seen between Tfreg number and viremia, suggesting possible dysfunction and suppression of an effective fCD8 cell immune response. Our data suggest that control of virus-infected cells in B cell follicles not only depends on fCD8 cell cytotoxicity but also on complex fCD8 cell associations with Tfh cells and Tfreg.
Clec9A+ Dendritic Cells Are Not Essential for Antitumor CD8+ T Cell Responses Induced by Poly I:C Immunotherapy
Authors: Gilfillan Connie B. , Kuhn Sabine , Baey Camille , Hyde Evelyn J. , Yang Jianping , Ruedl Christiane , Ronchese Franca
Published: March 2018

In the steady state, tumors harbor several populations of dendritic cells (DCs) and myeloid cells that are key regulators of the intratumoral immune environment. Among these cells, migratory CD103+ cross-presenting DCs are thought to be critical for tumor-specific CTL responses and tumor resistance. However, it is unclear whether this prominent role also extends to immunotherapy. We used a murine orthotopic mammary tumor model, as well as Clec9A–diphtheria toxin receptor mice that can be depleted of the specialized cross-presenting CD8α+ and CD103+ DC1 subsets, to investigate the role of these DCs in immunotherapy. Treatment with monosodium urate crystals and mycobacteria at the tumor site delayed tumor growth and required DC1s for efficacy. In contrast, treatment with poly I:C was equally effective regardless of DC1 depletion. Neither treatment affected myeloid-derived suppressor cell numbers in the spleen or tumor. Similar experiments using subcutaneous B16 melanoma tumors in BATF3-knockout mice confirmed that CD103+ DCs were not necessary for successful poly I:C immunotherapy. Nevertheless, adaptive immune responses were essential for the response to poly I:C, because mice depleted of CD8+ T cells or all DC subsets were unable to delay tumor growth. In vivo experiments showed that DC1 and DC2 subsets were able to take up tumor Ags, with DC2s making up the larger proportion of lymph node DCs carrying tumor material. Both DC subsets were able to cross-present OVA to OT-I T cells in vitro. Thus, immunotherapy with poly I:C enables multiple DC subsets to cross-present tumor Ag for effective antitumor immune responses.
Epitope-Binding Characteristics for Risk versus Protective DRB1 Alleles for Visceral Leishmaniasis
Authors: Singh Toolika , Fakiola Michaela , Oommen Joyce , Singh Akhil Pratap , Singh Abhishek K. , Smith Noel , Chakravarty Jaya , Sundar Shyam , Blackwell Jenefer M.
Published: March 2018

HLA-DRB1 is the major genetic risk factor for visceral leishmaniasis (VL). We used SNP2HLA to impute HLA-DRB1 alleles and SNPTEST to carry out association analyses in 889 human cases and 977 controls from India. NetMHCIIpan 2.1 was used to map epitopes and binding affinities across 49 Leishmania vaccine candidates, as well as across peptide epitopes captured from dendritic cells treated with crude Leishmania Ag and identified using mass spectrometry and alignment to amino acid sequences of a reference Leishmania genome. Cytokines were measured in peptide-stimulated whole blood from 26 cured VL cases and eight endemic healthy controls. HLA-DRB1*1501 and DRB1*1404/DRB1*1301 were the most significant protective and risk alleles, respectively, with specific residues at aa positions 11 and 13 unique to protective alleles. We observed greater peptide promiscuity in sequence motifs for 9-mer core epitopes predicted to bind to risk (*1404/*1301) compared with protective (*1501) DRB1 alleles. There was a higher frequency of basic amino acids in DRB1*1404/*1301-specific epitopes compared with hydrophobic and polar amino acids in DRB1*1501-specific epitopes at anchor residues pocket 4 and pocket 6, which interact with residues at DRB1 positions 11 and 13. Cured VL patients made variable, but robust, IFN-γ, TNF, and IL-10 responses to 20-mer peptides based on captured epitopes, with peptides based on DRB1*1501-captured epitopes resulting in a higher proportion (odds ratio 2.23, 95% confidence interval 1.17–4.25, p = 0.017) of patients with IFN-γ/IL-10 ratios > 2-fold compared with peptides based on DRB1*1301-captured epitopes. Our data provide insight into the molecular mechanisms underpinning the association of HLA-DRB1 alleles with risk versus protection in VL in humans.
Resident Fuel Levels: Reframing, Assessing, and Addressing Well-Being
Authors: Scielzo Shannon Amerilda , Weigle David C. , Kazi Salahuddin (Dino)
Published: March 2018

Background 

To optimize resident learning, programs need to readily assess resident well-being. There is a lack of easy-to-use, acceptable instruments for this task.

Objective 

We created a well-being “fuel gauge,” and assessed the acceptability and feasibility of this weekly electronic communication pipeline for residents to report and discuss their well-being.

Methods 

A well-being fuel gauge assessment was administered weekly over the course of 1 academic year (July 2016 to June 2017) in a large internal medicine residency program. The well-being gauge asked residents to report their fuel levels using a 1 to 5 Likert-type scale (1, empty; 3, half tank; and 5, full tank). Residents who provided low scores (1 or 2) were contacted by program leadership, and the program director sent weekly e-mail updates that addressed residents' comments on their well-being fuel gauge.

Results 

Of 163 residents, 149 (91%) provided data on their well-being fuel gauge, with a 53% average weekly response rate. Fifty-four percent of residents (80 of 149) reported a low score over the course of the year, and 4 residents only used the assessment to report a low score. Comments on average consisted of 280 characters (SD = 357) and were lengthier and more prevalent with lower fuel gauge scores. We analyzed the relationship between scores and comments.

Conclusions 

The well-being fuel gauge was well accepted by most residents and was easy to administer and to oversee by program directors. It facilitated ongoing monitoring of well-being and follow-up to address factors contributing to low well-being.
A look at the advanced learners' use of mobile devices for English language study: Insights from interview data
Authors: Kruk Mariusz
Published: March 2018

The paper discusses the results of a study which explored advanced learners of English engagement with their mobile devices to develop learning experiences that meet their needs and goals as foreign language learners. The data were collected from 20 students by means of a semi-structured interview. The gathered data were subjected to qualitative and quantitative analysis. The results of the study demonstrated that, on the one hand, some subjects manifested heightened awareness relating to the advantageous role of mobile devices in their learning endeavors, their ability to reach for suitable tools and retrieve necessary information so as to achieve their goals, meet their needs and adjust their learning of English to their personal learning styles, and on the other, a rather intuitive and/or ad hoc use of their mobile devices in the classroom.
Combinación de fibras de acero de última generación para el refuerzo de hormigón autocompactante
Authors: Galvez Jaime , Alberti Marcos G. , Enfedaque Alejandro , Cortez Adriana
Published: March 2018

En las últimas décadas, el hormigón reforzado con fibras (HRF) ha avanzado hacia aplicaciones estructurales, permitiendo la sustitución del refuerzo con barras corrugadas por fibras, especialmente de acero [1, 2]. Para la utilización estructural del hormigón reforzado con fibras se utilizan normalmente valores de resistencia a la tracción por flexión, tal y como refleja la normativa existente de referencia [3, 4]. Los resultados de estos ensayos están fuertemente influidos por la orientación y distribución de las fibras en la superficie de fractura, por lo que la combinación del HRF con hormigón autocompactante (HAC) mejora los resultados de fractura en dicha dirección gracias a la orientación preferente que toman las fibras en la dirección del flujo de hormigonado [5, 6]. El hormigón reforzado con fibras de acero (HRFA) permite además el uso de fibras con los extremos formando patillas que, junto con un alto módulo de elasticidad, facilitan la obtención de resultados aptos para piezas estructurales [7, 8]. No obstante, la aportación durante el amasado de altos contenidos de fibras rígidas provoca una disminución de la trabajabilidad y no permite la obtención sencilla de un hormigón que mantenga las propiedades autcompactantes en estado fresco [9]. Por otro lado, las sinergias encontradas combinando distintas tecnologías de hormigón también se han encontrado combinando tipologías de fibras diferentes [10], lo que abre un importante abanico de posibilidades como la combinación de fibras con distinta longitud.En esta investigación se presentan los resultados de un trabajo experimental con el objetivo de optimizar los procesos de diseño de HAC reforzado con fibras de acero para  obtener mezclas robustas con alta resistencia y manteniendo sus propiedades en estado fresco. Se realizó una campaña experimental en la que se elaboró un HAC sin fibras de referencia (H0) al que después se añadieron 70kg/m3 de fibras de acero (H70). Además se combinaron por igual dos tipos de fibras de acero con un contenido total de 70kg/m3 (H70M). Con estas 3 mezclas se estudió la influencia de la incorporación de altos contenidos y tipos de fibras de acero en las propiedades en estado fresco del hormigón autocompactante. Posteriormente se caracterizaron las propiedades mecánicas y en fractura de los hormigones fabricados obteniendo resultados que mostraron las sinergias en la utilización de dos tipologías de fibras.DOI: http://dx.doi.org/10.4995/HAC2018.2018.5152
Concreto autoadensável: estudos de dosagem e validação de campo
Authors: Formagini Sidiclei , Barreto Lorraine Barbosa Mendes , Schanoski Paulo Sérgio , Riva Gilson Secco
Published: March 2018

Concretos autoadensáveis (CAA) apresentam características de alta fluidez em seu estado fresco, fluindo com relativa facilidade mesmo em elementos esbeltos ou com alta densidade de armadura, dispensando a necessidade de adensamento mecânico. No estado endurecido apresenta propriedades superiores ao concreto tradicional, como a resistência à compressão, maior integridade dos elementos e maior durabilidade e vida útil. Para que o CAA cumpra a todas estas propriedades é necessário: escolha correta dos materiais constituintes; proporcionamento eficiente da mistura granular seca, em função do máximo empacotamento granular; uso eficiente de um aditivo químico de terceira geração; processos eficientes de mistura, transporte e aplicação. Sendo assim, este trabalho apresenta estudo de dosagem experimental de misturas de CAA e suas caracterizações nos estados fresco e endurecido, bem como a validação em campo por meio de sua aplicação em paredes esbeltas de concreto. Os CAA foram produzidos com cimento CP V ARI RS, areia fina natural, agregado basáltico britado com diâmetro máximo de 9,5mm e aditivo químico a base de policarboxilato. O proporcionamento da mistura granular foi elaborado utilizando-se a teoria do modelo de empacotamento compressível, correlacionada com propriedades almejadas no estado fresco e no endurecido. Os CAA produzidos experimentalmente, de acordo com os parâmetros da norma NBR 15823-1 (ABNT, 2010), foram enquadrados no estado fresco como autoadensáveis nos testes de espalhamento pelo cone de Abrams, tempo de viscosidade plástica aparente, habilidade passante pela caixa L com utilização de três barras, viscosidade plástica aparente pelo funil V. No estado endurecido, apresentaram resistência à compressão aos 28 dias enquadrando-se na classe C40, com módulos estático de elasticidade à compressão superior a 30 GPa, e resistências à tração por compressão diametral na ordem de 10% da compressão simples. A validação do CAA foi realizada com produção em escala real, onde o CAA foi aplicado na construção de um empreendimento comercial cujas paredes são em concreto. Observou-se que o concreto manteve as propriedades obtidas em laboratório tanto nos estados fresco e endurecido, enquadrando-se dentro dos parâmetros da norma NBR 15823-1 (ABNT, 2010).DOI: http://dx.doi.org/10.4995/HAC2018.2018.5277
Influência da adição de fibras metálicas em concreto autoadensável no estado endurecido
Authors: Silva Gisele , Cristofoli Tiago , Tutikian Bernardo , Christ Roberto
Published: March 2018

A utilização do concreto autoadensável reforçado com fibras permite um grande avanço nas propriedades do concreto convencional. As fibras são adicionadas à mistura com a finalidade de melhorar suas propriedades mecânicas no estado endurecido, aliadas às características de alta trabalhabilidade e sem segregação, quando no estado fresco. Este compósito apresenta uma dispersão mais uniforme das fibras dentro dos elementos estruturais, graças à eliminação de compactação e vibrações, visto que as vibrações tendem a causar a segregação das fibras. Assim, podem ser executados elementos estruturais de espessuras reduzidas com alta qualidade, majorando sua resistência à tração na flexão e suavizando a curva de tensão-deformação, quando comparados ao concreto sem incorporação de fibras. Ainda, pode aumentar a segurança com a prevenção de fissuras e o aumento da tenacidade do concreto. Os tipos de fibras comumente utilizadas são de origem metálica, constituídas de aço carbono e sintéticas, com variações de polímeros inorgânicos. Elas exercem diferente influência no comportamento do material. De modo a verificar a influência da utilização da adição de fibras nas propriedades do material, foi dosado um traço de concreto autoadensável, com fibras de aço de três fatores de forma, nas porcentagens de 0,25%, 0,5% e 1,0% em relação ao volume total do material.  Após a avaliação dos resultados foi possível afirmar que a mistura testada com melhores resultados possui uma taxa de 1,0% da fibra com maior fator de forma. Apresentou perda de apenas 9,1% na resistência à compressão, aumento de 261% da resistência à tração na flexão e mais de 31 vezes o acréscimo do valor de fator de tenacidade em relação à mistura referência. Este estudo mostra que o concreto autoadensável com a incorporação de fibras metálicas tem aplicabilidade em situações onde é necessária elevada resistência a esforços de tração e elevada tenacidade, podendo ser utilizado em elementos onde se busca uma redução de armadura de tração e aumento da vida útil, contribuindo para a segurança e qualidade.DOI: http://dx.doi.org/10.4995/HAC2018.2018.5369