bluuebunny/crossref_metadata_2025 huggingface dataset:
SOFIA MID-INFRARED IMAGING AND CSO SUBMILLIMETER POLARIMETRY OBSERVATIONS OF G034.43+00.24 MM1*
Authors: Jones T. J. , Gordon Michael , Shenoy Dinesh , Gehrz R. D. , Vaillancourt John E. , Krejny M.
Published: May 2016

We present 11.1 to 37.1 μm imaging observations of the very dense molecular cloud core MM1 in G034.43+00.24 using FORCAST on SOFIA and submillimeter (submm) polarimetry using SHARP on the Caltech Submillimeter Observatory. We find that at the spatial resolution of SOFIA, the point-spread function (PSF) of MM1 is consistent with being a single source, as expected based on millimeter (mm) and submm observations. The spectral energy distributions (SEDs) of MM1 and MM2 have a warm component at the shorter wavelengths not seen in mm and submm SEDs. Examination of H(1.65 μm) stellar polarimetry from the Galactic Plane Infrared Polarization Survey shows that G034 is embedded in an external magnetic field aligned with the Galactic Plane. The SHARP polarimetry at 450 μm shows a magnetic field geometry in the vicinity of MM1 that does not line up with either the Galactic Plane or the mean field direction inferred from the CARMA interferometric polarization map of the central cloud core, but is perpendicular to the long filament in which G034 is embedded. The CARMA polarimetry does show evidence for grain alignment in the central region of the cloud core, and thus does trace the magnetic field geometry near the embedded Class 0 YSO.
A DEEP SEARCH FOR ADDITIONAL SATELLITES AROUND THE DWARF PLANET HAUMEA
Authors: Burkhart Luke D. , Ragozzine Darin , Brown Michael E.
Published: May 2016

Haumea is a dwarf planet with two known satellites, an unusually high spin rate, and a large collisional family, making it one of the most interesting objects in the outer solar system. A fully self-consistent formation scenario responsible for the satellite and family formation is still elusive, but some processes predict the initial formation of many small moons, similar to the small moons recently discovered around Pluto. Deep searches for regular satellites around Kuiper belt objects are difficult due to observational limitations, but Haumea is one of the few for which sufficient data exist. We analyze Hubble Space Telescope (HST) observations, focusing on a 10-consecutive-orbit sequence obtained in 2010 July, to search for new very small satellites. To maximize the search depth, we implement and validate a nonlinear shift-and-stack method. No additional satellites of Haumea are found, but by implanting and recovering artificial sources, we characterize our sensitivity. At distances between ∼10,000 and ∼350,000 km from Haumea, satellites with radii as small as ∼10 km are ruled out, assuming an albedo (

) similar to Haumea. We also rule out satellites larger than ≳40 km in most of the Hill sphere using other HST data. This search method rules out objects similar in size to the small moons of Pluto. By developing clear criteria for determining the number of nonlinear rates to use, we find that far fewer shift rates are required (∼35) than might be expected. The nonlinear shift-and-stack method to discover satellites (and other moving transients) is tractable, particularly in the regime where nonlinear motion begins to manifest itself.
3.6 AND 4.5 μm SPITZER PHASE CURVES OF THE HIGHLY IRRADIATED HOT JUPITERS WASP-19b AND HAT-P-7b
Authors: Wong Ian , Knutson Heather A. , Kataria Tiffany , Lewis Nikole K. , Burrows Adam , Fortney Jonathan J. , Schwartz Joel , Shporer Avi , Agol Eric , Cowan Nicolas B. , Deming Drake , Désert Jean-Michel , Fulton Benjamin J. , Howard Andrew W. , Langton Jonathan , Laughlin Gregory , Showman Adam P. , Todorov Kamen
Published: May 2016

We analyze full-orbit phase curve observations of the transiting hot Jupiters WASP-19b and HAT-P-7b at 3.6 and 4.5 μm, obtained using the Spitzer Space Telescope. For WASP-19b, we measure secondary eclipse depths of

and

at 3.6 and 4.5 μm, which are consistent with a single blackbody with effective temperature 2372 ± 60 K. The measured 3.6 and 4.5 μm secondary eclipse depths for HAT-P-7b are

and

, which are well described by a single blackbody with effective temperature 2667 ± 57 K. Comparing the phase curves to the predictions of one-dimensional and three-dimensional atmospheric models, we find that WASP-19b’s dayside emission is consistent with a model atmosphere with no dayside thermal inversion and moderately efficient day–night circulation. We also detect an eastward-shifted hotspot, which suggests the presence of a superrotating equatorial jet. In contrast, HAT-P-7b’s dayside emission suggests a dayside thermal inversion and relatively inefficient day–night circulation; no hotspot shift is detected. For both planets, these same models do not agree with the measured nightside emission. The discrepancies in the model-data comparisons for WASP-19b might be explained by high-altitude silicate clouds on the nightside and/or high atmospheric metallicity, while the very low 3.6 μm nightside planetary brightness for HAT-P-7b may be indicative of an enhanced global C/O ratio. We compute Bond albedos of 0.38 ± 0.06 and 0 (

at

) for WASP-19b and HAT-P-7b, respectively. In the context of other planets with thermal phase curve measurements, we show that WASP-19b and HAT-P-7b fit the general trend of decreasing day–night heat recirculation with increasing irradiation.
THE DETECTABILITY OF MILLIMETER-WAVE MOLECULAR ROTATIONAL TRANSITIONS
Authors: Liszt Harvey S. , Pety Jerome
Published: May 2016

Elaborating on a formalism that was first expressed some 40 years ago, we consider the brightness of low-lying millimeter-wave rotational lines of strongly polar molecules at the threshold of detectability. We derive a simple expression relating the brightness to the line-of-sight integral of the product of the total gas and molecular number densities and a suitably defined temperature-dependent excitation rate into the upper level of the transition. Detectability of a line is contingent only on the ability of a molecule to channel enough of the ambient thermal energy into the line, and the excitation can be computed in bulk by summing over rates without solving the multi-level rate equations, or computing optical depths and excitation temperatures. Results for

, HNC, and CS are compared with escape-probability solutions of the rate equations using closed-form expressions for the expected range of validity of our ansatz, with the result that gas number densities as high as

or optical depths as high as 100 can be accommodated in some cases. For densities below a well-defined upper bound, the range of validity of the discussion can be cast as an upper bound on the line brightness which is 0.3 K for the J = 1–0 lines and 0.8–1.7 K for the J = 2–1 lines of these species. The discussion casts new light on the interpretation of line brightnesses under conditions of weak excitation, simplifies derivation of physical parameters, and eliminates the need to construct grids of numerical solutions of the rate equations.
« Le collège c’est une prison, ici c’est le cachot ». Un apprentissage de la déviance scolaire sous surveillance
Authors: Garnier Juliette
Published: May 2016

Face à une école qui peine à gérer l’hétérogénéité de son public, les réponses éducatives apportées aux élèves qui posent problème à l’institution sont individualisées, en fonction de besoins supposés spécifiques de certains élèves, et notamment de ceux vivant sur les territoires cibles des politiques d’éducation prioritaire. Les pouvoirs locaux, en multipliant les « dispositifs » tentant de répondre à chacune des difficultés rencontrées dans l’espace de l’école, se saisissent des questions de « déviances scolaires ». Cet article est issu d’une recherche de type ethnographique menée sur une structure associative prenant en charge, à l’intérieur d’un collège, les élèves exclus temporairement. Il revient sur les effets d’une ségrégation scolaire organisée en interne sur les comportements perturbateurs qu’elle est supposée enrayer.
Territoires, offre de formation et expérience du décrochage scolaire : une étude de cas
Authors: Bell Lucy , Bernard Pierre-Yves
Published: May 2016

La mobilisation autour de la question du décrochage scolaire répond à la difficulté grandissante rencontrée par les non diplômés à trouver un emploi. Les facteurs de risque individuels et familiaux sont aujourd’hui connus. Toutefois, une dimension moins explorée des inégalités de décrochage scolaire relève des spécificités territoriales dans lesquelles s’inscrit l’expérience scolaire des élèves. À partir d’une enquête quantitative dans le département de Loire-Atlantique, nous avons mis en évidence des différences significatives de motifs de décrochage scolaire selon l’offre de formation initiale en enseignement secondaire de second cycle. En distinguant trois types de territoires en fonction de leurs offres de formation, ce travail révèle que, paradoxalement, ce sont les territoires périurbains qui favorisent le cumul de motifs de décrochage.
Devenir élève au Brésil en contexte ségrégué. Un défi impossible ?
Authors: Baumann Burgos Marcelo
Published: May 2016

La massification de l’accès à l’école au Brésil se développe à partir des années 1970, avec l’arrivée croissante des enfants et des adolescents issus de familles populaires. Ce processus est directement lié à la transition démocratique du pays, alors que la Constitution de 1988 donne une place nouvelle aux droits de l’enfant et de l’adolescent dans le système juridique brésilien, et affirme le droit à l’apprentissage scolaire. Cet article décrit le contexte général de développement de ce processus de massification et, plus spécifiquement, interroge les modalités de construction de l’identité d’élève chez les enfants et adolescents de classes populaires, en lien avec les “effets de lieu”. Cet article s’appuie sur une étude de cas qui analyse l’accès au droit à l’éducation scolaire des enfants et des adolescents qui vivent dans une grande favela de Rio de Janeiro.
« Je pouvais espérer, j’étais en droit de penser que cela pouvait se passer autrement. »
Authors: Beneduce Roberto , Taliani Simona , Martinez Odile
Published: May 2016

L’article questionne un aspect particulier de ce que les auteurs appellent les « archives postcoloniales » : les pratiques menant à l’adoptabilité d’enfants nés de parents immigrés. En s’appuyant sur les données de leur recherche ethnographique concernant la condition de parents immigrés dans le nord de l’Italie, les auteurs interrogent la généalogie coloniale des procédures thérapeutiques et des formes d’assistance sociale appliquées aux familles étrangères, ainsi que le « dispositif » qui les transforme en descendances dépossédées.
La tombe de Benito Mussolini à Predappio
Authors: Giampaoli Michelangelo
Published: May 2016

Soixante-dix ans après la fin de la Seconde Guerre mondiale et la mort de Mussolini, la tombe du Duce à Predappio, en Emilie-Romagne, est un lieu de rencontre et de commémoration pour les nostalgiques de la période fasciste. Chaque année, à l’occasion de dates particulièrement symboliques, des milliers de personnes venues de toute l’Italie se rendent à Predappio pour rendre hommage au fondateur du fascisme, à travers des formes et pratiques de dévotion qui ne manquent pas de susciter les critiques de l’opinion publique. L’administration de la ville peine à faire face à ces « pèlerins » – touristes, dont la présence crée l’embarras mais qui contribuent, dans le même temps, de façon significative à enrichir l’économie locale. Cet article examine toutes ces contradictions.
De Cellamare à Pontcallec. Une mise en scène dumasienne de la Régence
Authors: Andre Valérie
Published: May 2016

« Vous avez plus appris d’histoire au peuple que tous les historiens réunis » ! La phrase de Michelet est célèbre. Elle consacre avec autorité l’importance de l’écriture dumasienne de l’Histoire, du roman au théâtre en passant par les scènes historiques et bien sûr la chronique. Les études consacrées à Dumas sont innombrables, tous les aspects de l’œuvre du polygraphe semblent avoir été abordés et mis en relation les uns avec les autres. Le romancier et le dramaturge n’ont pas fait oublier l’historien. La critique dénombre trois grands cycles – le Moyen Âge et les guerres de religion, le xvii e siècle et la Révolution –, les deux premiers ayant quelque peu oblitéré l’importance du troisième. Le regard rétrospectif porté par Dumas sur le xviii e siècle et la fracture révolutionnaire est pourtant essentiel : le discours historique lui permet en effet de parler du présent, la conception téléologico-providentialiste qu’il professe infléchit sa lecture de l’événement ou de l’anecdote en fonction du temps de l’écriture. Une courte période se détache dans ce xviii e siècle foisonnant et multiple, huit années d’exception qui assurent une coupure radicale avec le siècle de Louis XIV : la Régence de Philippe d’Orléans à laquelle Dumas consacra plusieurs grands ouvrages. Pour l’écrivain, la Régence constitue en effet un moment charnière de l’Histoire que la fiction et la chronique permettent de mettre au jour.
Beyond Program Objectives
Authors: Baessler Matthew , Best William , Sexton Martha
Published: May 2016

Graduate students in eight diverse health care professional programs participated together in a pilot course entitled, “An Interprofessional Approach to Patient Care.” Through postcourse discussions with the clinical nurse leader students, faculty discovered that beyond meeting program objectives, the nursing learners gained numerous unexpected insights about interprofessional collaborative practice.

J Contin Educ Nurs.
2016;47(6):248–249.
Moving on From Millennials: Preparing for Generation Z
Authors: Shatto Bobbi , Erwin Kelly
Published: May 2016

Much has been written about teaching Millennials; however, little has been discussed about Generation Z—those just entering college. Nursing instructors must adapt to the upcoming generation's mobile tech-savviness and self-directed learning, which often is accompanied by a lack of critical thinking skills. Teaching strategies and incorporating technology are highlighted.

J Contin Educ Nurs.
2016;47(6):253–254.
La semantica della preposizione ὑπέρ nel greco omerico
Authors: Zanchi Chiara
Published: May 2016

[it] Le preposizioni sono parole altamente polisemiche, che, nel greco omerico, mantengono o non hanno ancora sviluppato significati, poi eliminati o convenzionalizzati nel greco postomerico. In questo articolo, analizzo la semantica della preposizione ὑπέρ nel greco omerico, usando la terminologia della grammatica cognitiva. Inoltre, adotto il modello della polisemia strutturata per individuare il significato originario di ὑπέρ e per distinguere, tra i suoi significati, quelli innescati dal contesto di occorrenza da quelli immagazzinati in modo indipendente nella memoria del parlante. Facendo questa distinzione, tengo conto anche dello sviluppo dei significati di ὑπέρ nel greco postomerico, e dell’interazione tra preposizione e caso morfologico. Organizzo poi i significati indipendenti in una rete semantica, collegandoli direttamente o indirettamente al significato originario di tipo spaziale. Infine, mostro in quali modi dal significato spaziale di base si sviluppano gli altri significati, spaziali o astratti.
Ecos del Ión platónico en los escritos de Filón de Alejandría
Authors: Delgado Carolina
Published: May 2016

El presente artículo se propone identificar la presencia del Ión platónico en los escritos de Filón de Alejandría; campo de trabajo éste que, a diferencia de otros diálogos platónicos, no ha sido aún explorado en la investigación dedicada al alejandrino. Para ello se efectúa aquí un rastreo intertextual, atendiendo a los lugares de esta temprana obra platónica que resuenan en el corpus filoniano. Los datos que resultan de esa confrontación son relevantes en vistas a delimitar si, y en qué medida, Filón se ha apropiado del motivo platónico de la inspiración divina.
Amiano Marcelino y las Res gestae
Authors: Harto Trujillo Mª Luisa
Published: May 2016

Nos planteamos la intención de Amiano Marcelino al escribir su obra y, sobre todo, por qué escribió ese tipo de obra, enlazando con la historiografía anterior y oponiéndose a las corrientes imperantes en su época.
A Study of Crack-Face Boundary Conditions for Piezoelectric Strip Cut Along Two Equal Collinear Cracks
Authors: Bhargava R. R. , Verma Pooja Raj
Published: May 2016

A problem of two equal, semi-permeable, collinear cracks, situated normal to the edges of an infinitely long piezoelectric strip is considered. Piezoelectric strip being prescribed out-of-plane shear stress and in-plane electric-displacement. The Fourier series and integral equation methods are adopted to obtain analytical solution of the problem. Closed-form analytic expressions are derived for various fracture parameters viz. crack-sliding displacement, crack opening potential drop, field intensity factors and energy release rate. An numerical case study is considered for poled PZT–5H, BaTiO3 and PZT–6B piezoelectric ceramics to study the effect of applied electro-mechanical loadings, crack-face boundary conditions as well as inter-crack distance on fracture parameters. The obtained results are presented graphically, discussed and concluded.
Deep ocean mass fluxes in the coastal upwelling off Mauritania from 1988 to 2012: variability on seasonal to decadal timescales
Authors: Fischer Gerhard , Romero Oscar , Merkel Ute , Donner Barbara , Iversen Morten , Nowald Nico , Ratmeyer Volker , Ruhland Götz , Klann Marco , Wefer Gerold
Published: May 2016

Abstract. A more than two-decadal sediment trap record from the Eastern Boundary Upwelling Ecosystem (EBUE) off Cape Blanc, Mauritania, is analysed with respect to deep ocean mass fluxes, flux components and their variability on seasonal to decadal timescales. The total mass flux revealed interannual fluctuations which were superimposed by fluctuations on decadal timescales. High winter fluxes of biogenic silica (BSi), used as a measure of marine production (mostly by diatoms) largely correspond to a positive North Atlantic Oscillation (NAO) index (December–March). However, this relationship is weak. The highest positive BSi anomaly was in winter 2004–2005 when the NAO was in a neutral state. More episodic BSi sedimentation events occurred in several summer seasons between 2001 and 2005, when the previous winter NAO was neutral or even negative. We suggest that distinct dust outbreaks and deposition in the surface ocean in winter and occasionally in summer/autumn enhanced particle sedimentation and carbon export on short timescales via the ballasting effect. Episodic perturbations of the marine carbon cycle by dust outbreaks (e.g. in 2005) might have weakened the relationships between fluxes and large-scale climatic oscillations. As phytoplankton biomass is high throughout the year, any dry (in winter) or wet (in summer) deposition of fine-grained dust particles is assumed to enhance the efficiency of the biological pump by incorporating dust into dense and fast settling organic-rich aggregates. A good correspondence between BSi and dust fluxes was observed for the dusty year 2005, following a period of rather dry conditions in the Sahara/Sahel region. Large changes of all bulk fluxes occurred during the strongest El Niño-Southern Oscillation (ENSO) in 1997–1999 where low fluxes were obtained for almost 1 year during the warm El Niño and high fluxes in the following cold La Niña phase. For decadal timescales, Bakun (1990) suggested an intensification of coastal upwelling due to increased winds (''Bakun upwelling intensification hypothesis''; Cropper et al., 2014) and global climate change. We did not observe an increase of any flux component off Cape Blanc during the past 2 and a half decades which might support this. Furthermore, fluxes of mineral dust did not show any positive or negative trends over time which might suggest enhanced desertification or ''Saharan greening'' during the last few decades.
Monitoring the temperature dependent elastic and anelastic properties in isotropic polycrystalline ice using resonant ultrasound spectroscopy
Authors: Vaughan Matthew J. , van Wijk Kasper , Prior David J. , Bowman M. Hamish
Published: May 2016

Abstract. The elastic and anelastic properties of ice are of interest in the study of the dynamics of sea ice, glaciers and ice sheets. Resonant ultrasound spectroscopy allows quantitative estimates of these properties and aids calibration of active and passive seismic data gathered in the field. The elastic constants and attenuation constant in man-made polycrystalline isotropic ice cores decrease (reversibly) with increasing temperature. All elastic properties and attenuation vary with ice temperature, but especially compressional-wave speed and attenuation prove sensitive to temperature, indicative of pre-melting of the ice. This method of resonant ultrasound can be deployed in the field, for those situations where shipping samples is difficult (e.g. remote locations), or where the properties of ice change rapidly after extraction (e.g., in the case of sea ice)
Late Correction of Neck Deformity in Healed Severe Slipped Capital Femoral Epiphysis: Short-Term Clinical Outcomes
Authors: Balakumar Balasubramanian , Madan Sanjeev
Published: May 2016

Purpose

Contemporary methods for the management of neck deformity following a healed severe slipped capital femoral epiphysis (SCFE) include subcapital neck osteotomy.

Methods

18 patients with chronic severe SCFE in the oblique plane (mean slip angle = 70°) constituted the study group. 6 patients with an open physis underwent modified Dunn capital realignment and 12 patients with a closed physis underwent surgical dislocation with a corrective neck osteotomy. 10 patients already had an in-situ pinning.

Results

The mean follow-up was 4.5 years (3-6 years). The mean preoperative modified Harris Hip Score (mHHS) and nonarthritic hip score (NAHS) were 24 and 40 respectively, followed by a score of 89 and 92 respectively at the last follow-up (p = 0.0002). Radiologically, all the parameters showed a significant correction. The mean pre- and postoperative values of alpha angle were 79.8 and 34.5 respectively (p = 0.0002); AP slip angle being 36.7 and 14.8 (p = 0.002); lateral slip angle being 54.2 and 13.6 (p = 0.0002); oblique plane slip angle being 70.7 and 20.8 (p = 0.0002) and centre trochanter distance being -6.9 and 1.2 (p = 0.002). The major complications seen were nonunion of the neck osteotomy (n = 1/12) and chondrolysis (n = 1/6) in the modified Dunn's group. The overall complication rate was 11%. There was no statistically significant difference in outcome between the 2 groups clinically and radiologically.

Conclusions

Femoral neck osteotomy is a potentially rewarding technique to correct severe neck deformities and restoring hip function in the short term.
Beam Species Characteristics of High Current Ion Source for EAST Neutral Beam Injector
Authors: Wang Y , Liu Z M , Yan J Y , Liang L Z , Hu C D
Published: May 2016

During the experiment of high-current ion source on EAST NBI test bed, the Doppler shift spectroscopy (DSS) is used to measure the hydrogen alpha lines emitted by excited atoms. The multi-peak Gaussian fitting gives the distribution of the original DSS spectra data, the beam energy and the fractions of the beam species can be calculated for different operation parameters of ion source. It is known that the proton ratio increases with the arc power, the beam energy and the perveance, this phenomenon can provide a reference for higher power neutral beam extraction. According to the experimental results, the maximum proton ratio is near 78% under the arc power is about 65kW. This result indicates that the high-current ion source extraction match the design requirements.
The Role of Socioeconomic Factor in Promoting Higher Education in the State of Kuwait
Authors: Darwish Salwa Al
Published: May 2016

The purpose of this research study is to determine the level of influence of parental education, social and financial status on their senior college students by encouraging them to pursue higher degrees. The sample of the study was 313 senior college students randomly selected from private and public universities in Kuwait to answer the questionnaire. Then followed by interviewing some of these 313 students for triangulation. The result of the findings shows that the impact of parents on college student’s academic achievement should be mediated through college student’s own self-perception and the environments in which students grew up. The findings show that there is a strong influence and positive motivations on the development of the students’ own beliefs. Moreover, the study shows other factors such as the family socioeconomic background, the students’ social influences, the students’ academic achievement, in addition to the educational achievement of both parents which all have impact on students’ decisions to pursue higher degrees.
Method of improving image sharpness for annular-illumination scanning electron microscopes
Authors: Enyama Momoyo , Hamada Koichi , Fukuda Muneyuki , Kazumi Hideyuki
Published: May 2016

Annular illumination is effective in enhancing the depth of focus for scanning electron microscopes (SEMs). However, owing to high side lobes of the point-spread function (PSF), annular illumination results in poor image sharpness. The conventional deconvolution method, which converts the PSF to a delta function, can improve image sharpness, but results in artifacts due to noise amplification. In this paper, we propose an image processing method that can reduce the deterioration of image sharpness. With this method, the PSF under annular illumination is converted to that under standard illumination. Through simulations, we verified that the image sharpness of SEM images under annular illumination with the proposed method can be improved without noise amplification.
In situ patterning of organic molecules in aqueous solutions using an
inverted electron-beam lithography system
Authors: Miyazako Hiroki , Ishihara Kazuhiko , Mabuchi Kunihiko , Hoshino Takayuki
Published: May 2016

A method for in situ controlling the detachment and deposition of organic
molecules such as sugars and biocompatible polymers in aqueous solutions by
electron-beam (EB) scan is proposed and evaluated. It was demonstrated that EB
irradiation could detach 2-methacryloyloxyethyl phosphorylcholine (MPC) polymers
from a silicon nitride membrane. Moreover, organic molecules such as cationic
polymers and sugars could be deposited on the membrane by EB irradiation.
Spatial distributions of scattered electrons were numerically simulated, and
acceleration voltage dependences of the detachment and deposition phenomena were
experimentally measured. The simulations and experimental results suggest that
the detachment of MPC polymers is mainly due to electrical effects of primary
electrons, and that the deposition of organic molecules is mainly due to
chemical reactions induced by primary electrons. In view of these findings, the
proposed method can be applied to in situ and nanoscale patterning such as the
fabrication of cell scaffolds.
Ferroelectric properties of (Pb,La)(Zr,Ti)O3 capacitors employing Al-doped ZnO top electrodes prepared by pulsed laser deposition under different oxygen pressures
Authors: Takada Yoko , Okamoto Naoki , Saito Takeyasu , Kondo Kazuo , Yoshimura Takeshi , Fujimura Norifumi , Higuchi Koji , Kitajima Akira
Published: May 2016

Al-doped ZnO (AZO) top electrodes were deposited under oxygen pressures from 0.02 to 20 Pa using pulsed laser deposition (PLD) to fabricate ferroelectric (Pb,La)(Zr,Ti)O3 capacitors. The oxygen pressure during PLD affected the surface morphology of the AZO top electrodes as well as the ferroelectric properties. In particular, the surface morphologies were dramatically altered by increasing oxygen pressure. We obtained desirable ferroelectric properties with the highest maximum polarization and lowest coercive voltage at around 2.0 Pa. The saturation characteristics, hydrogen degradation resistance, and fatigue resistance were almost unrelated to the oxygen pressure during PLD.
Effects of forming gas plasma treatment on low-temperature Cu–Cu direct bonding
Authors: Kim Sungdong , Nam Youngju , Kim Sarah Eunkyung
Published: May 2016

Low-temperature Cu–Cu direct bonding becomes of great importance as Cu is widely used as an interconnection material in the packaging industry. Preparing a clean surface is a key to successful Cu–Cu direct bonding. We investigated the effects of forming gas plasma treatment on the reduction of Cu oxide and Cu–Cu bonding temperature. As plasma input power and treatment time increased, Cu oxide could be effectively reduced, and this could be attributed to the enhanced chemical reaction between forming gas plasma and Cu oxide. When the bonding temperature was reduced from 415 to 300 °C, the bonding strength of the plasma-treated interface was increased from 1.8 to 5.55 J/m2 while that of the wet-treated interface was decreased.
PAUPAR lncRNA suppresses tumourigenesis by H3K4 demethylation in uveal melanoma
Authors: Ding Xia , Wang Xi , Lin Ming , Xing Yue , Ge Shengfang , Jia Renbing , Zhang He , Fan Xianqun , Li Jin
Published: May 2016

Uveal melanoma (UM) is the most common primary intraocular tumour in adults and has a high incidence. Nearly 50% of patients with UM develop metastases after diagnosis. Long noncoding RNAs (lncRNAs) are involved in both oncogenic and tumour suppression pathways. We show that lncRNA PAUPAR is present at low levels in UM tissues and cell lines and modulates the tumourigenesis of UM in vitro and in vivo. The ectopic expression of PAUPAR in UM cells revealed that PAUPAR acts as a necessary UM suppressor and induces the silencing of HES1 expression, which significantly reduces tumour metastasis. Mechanistically, PAUPAR modulates HES1 expression by inhibiting histone H3K4 methylation. These data support a role of this lncRNA as a novel therapeutic target in cancer prevention and treatment.
Convective transport of formaldehyde to the upper troposphere and lower stratosphere and associated scavenging in thunderstorms over the central United States during the 2012 DC3 study
Authors: Fried A. , Barth M.C. , Bela M. , Weibring P. , Richter D. , Walega J. , Li Y. , Pickering K. , Apel E. , Hornbrook R. , Hills A. , Riemer D. D. , Blake N. , Blake D.R. , Schroeder J. R. , Luo Z. J. , Crawford J. H. , Olson J. , Rutledge S. , Betten D. , Biggerstaff M. I. , Diskin G.S. , Sachse G. , Campos T. , Flocke F. , Weinheimer A. , Cantrell C. , Pollack I. , Peischl J. , Froyd K. , Wisthaler A. , Mikoviny T. , Woods S.
Published: May 2016

We have developed semi‐independent methods for determining CH2O scavenging efficiencies (SEs) during strong midlatitude convection over the western, south‐central Great Plains, and southeastern regions of the United States during the 2012 Deep Convective Clouds and Chemistry (DC3) Study. The Weather Research and Forecasting model coupled with chemistry (WRF‐Chem) was employed to simulate one DC3 case to provide an independent approach of estimating SEs and the opportunity to study CH2O retention in ice when liquid drops freeze. Measurements of CH2O in storm inflow and outflow were acquired on board the NASA DC‐8 and the NSF/National Center for Atmospheric Research Gulfstream V (GV) aircraft employing cross‐calibrated infrared absorption spectrometers. This study also relied heavily on the nonreactive tracersi‐/n‐butane andi‐/n‐pentane measured on both aircraft in determining lateral entrainment rates during convection as well as their ratios to ensure that inflow and outflow air masses did not have different origins. Of the five storm cases studied, the various tracer measurements showed that the inflow and outflow from four storms were coherently related. The combined average of the various approaches from these storms yield remarkably consistent CH2O scavenging efficiency percentages of: 54% ± 3% for 29 May; 54% ± 6% for 6 June; 58% ± 13% for 11 June; and 41 ± 4% for 22 June. The WRF‐Chem SE result of 53% for 29 May was achieved only when assuming complete CH2O degassing from ice. Further analysis indicated that proper selection of corresponding inflow and outflow time segments is more important than the particular mixing model employed.
Slot‐Die‐Coated V2O5 as Hole Transport Layer for Flexible Organic Solar Cells and Optoelectronic Devices
Authors: Beliatis Michail J. , Helgesen Martin , García‐Valverde Rafael , Corazza Michael , Roth Bérenger , Carlé Jon E. , Jørgensen Mikkel , Krebs Frederik C. , Gevorgyan Suren A.
Published: May 2016

Vanadium pentoxide has been proposed as a good alternative hole transport layer for improving device lifetime of organic photovoltaics. The article presents a study on the optimization of slot‐die‐coated vanadium oxide films produced with a roll coating machine with the aim of achieving scalable organic solar cells and photo‐detectors with improved performance. The effect of different diluents on the electrical properties of the vanadium oxide films is investigated, and methodologies for efficient interfacing of the anode are studied. Furthermore, the lifetime of the cells with incorporated vanadium oxide is investigated employing different encapsulation methods. Finally, an application of the manufactured scalable devices in proximity sensors is demonstrated using a 3D‐printed scaffold.
Visible Light Triggered CO2 Liberation from Silver Nanocrystals Incorporated Metal–Organic Frameworks
Authors: Li Haiqing , Hill Matthew R. , Doblin Christian , Lim Seng , Hill Anita J. , Falcaro Paolo
Published: May 2016

Widespread deployment of metal–organic frameworks (MOFs) for CO2 capture remains challenging due to the great energy‐penalty associated with their regeneration. To overcome this challenge, a new type of photodynamic carbon capture material synthesized by incorporating Ag nanocrystals with UiO‐66 (Ag/UiO‐66) framework is presented. Upon the irradiation of visible light, Ag nanocrystals within the composites serve as “nanoheaters” to convert photon energy into thermal energy locally. Driven by such light‐induced localized heat (LLH), the adsorbed CO2 within MOFs is remotely released. The CO2 desorption capacity of such Ag/UiO‐66 composites can be readily regulated by control over their Ag contents and the applied light intensity. Up to 90.5% of CO2 desorption is achieved under the investigated conditions. Distinct from the traditional light‐responsive MOFs for gas trigger release, currently developed LLH‐driven CO2 release method not only offers a promising solution to the heat‐insulating nature of MOFs, but also demonstrates a potentially low energy method to remotely regenerate MOF adsorbents given the utilization of naturally abundant visible light as efficient stimulus.
Strong, Machinable Carbon Aerogels for High Performance Supercapacitors
Authors: Kim Christine H. J. , Zhao Dandan , Lee Gyeonghee , Liu Jie
Published: May 2016

Designing macroscopic, 3D porous conductive materials with high mechanical strength is of great importance in many fields, including energy storage, catalysis, etc. This study reports a novel approach to fabricate polyaniline‐coated 3D carbon x‐aerogels, a special type of aerogels with mechanically strong, highly cross‐linked structure that allows the originally brittle aerogels machinable. This approach is accomplished by introducing a small amount of graphene into the sol–gel process of resorcinol and formaldehyde, followed by physical activation and subsequent cross‐linking with polyaniline via electropolymerization. The resulting x‐aerogels are not only porous and conductive, but also mechanically robust with high compressibility and fast recovery. The strong combination of these properties makes the x‐aerogels promising for high performance supercapacitors that are designed to provide additional functionality for wearable and portable electronics. Such multi‐functionality leads to a significant increase in electrochemical performance, in particular high volumetric capacitance, which results from the more densely packed electroactive structure in three dimensions. More importantly, monoliths of carbon x‐aerogels are machinable into thin slices without losing their properties, thus enabling effective integration into devices with different sizes and shapes.
Controlling Bone Graft Substitute Microstructure to Improve Bone Augmentation
Authors: Sheikh Zeeshan , Drager Justin , Zhang Yu Ling , Abdallah Mohamed‐Nur , Tamimi Faleh , Barralet Jake
Published: May 2016

Vertical bone augmentation procedures are frequently carried out to allow successful placement of dental implants in otherwise atrophic ridges and represent one of the most common bone grafting procedures currently performed. Onlay autografting is one of the most prevalent and predictable techniques to achieve this; however, there are several well documented complications and drawbacks associated with it and synthetic alternatives are being sought. Monetite is a bioresorbable dicalcium phosphate with osteoconductive and osteoinductive potential that has been previously investigated for onlay bone grafting and it is routinely made by autoclaving brushite to simultaneously sterilize and phase convert. In this study, monetite disc‐shaped grafts are produced by both wet and dry heating methods which alter their physical properties such as porosity, surface area, and mechanical strength. Histological observations after 12 weeks of onlay grafting on rabbit calvaria reveal higher bone volume (38%) in autoclaved monetite grafts in comparison with the dry heated monetite grafts (26%). The vertical bone height gained is similar for both the types of monetite grafts (up to 3.2 mm). However, it is observed that the augmented bone height is greater in the lateral than the medial areas of both types of monetite grafts. It is also noted that the higher porosity of autoclaved monetite grafts increases the bioresorbability, whereas the dry heated monetite grafts having lower porosity but higher surface area resorb to a significantly lesser extent. This study provides information regarding two types of monetite onlay grafts prepared with different physical properties that can be further investigated for clinical vertical bone augmentation applications.
Localized Surface Plasmon‐Enhanced Ultrathin Film Broadband Nanoporous Absorbers
Authors: Lu Jin You , Nam Sang Hoon , Wilke Kyle , Raza Aikifa , Lee Yoonkyung E. , AlGhaferi Amal , Fang Nicholas X. , Zhang TieJun
Published: May 2016

Ultrathin lossy films have attracted much attention due to their strong interference persisting inside the lossy dielectric film on a reflective substrate. Here, a plasmon‐enhanced ultrathin film broadband absorber is proposed by combining the ultrathin film absorber with localized surface plasmon resonances. This concept can be realized by patterning nanoholes on an absorber comprised of an absorptive ultrathin Ge film and a reflective Au layer, where the localized surface plasmon mode is activated by metallic pore‐shaped holes. The plasmonic enhancement is resulting from the pore‐shape localized resonance mode, which increases the optical path length through scattering and concentrates the incident light field near the interface of Ge/Au. The experimental characterization results of a nanoporous ultrathin film absorber, which is fabricated with a scalable laser interference lithography approach, demonstrate its superior light absorption performance. Several materials, such as Ag, Al, and Cu, are proposed as an alternative to Au, and they can also provide plasmonic enhancement to ultrathin films. Furthermore, through an efficient way to optimize the structural dimensions of the nanoporous ultrathin film absorber, a trilayer system of TiO2/Ge/Au achieves the total solar absorptance over 89.3% with a wavelength range of 400–1100 nm.
Fabrication of Highly Transparent and Flexible NanoMesh Electrode via Self‐assembly of Ultrathin Gold Nanowires
Authors: Gong Shu , Zhao Yunmeng , Yap Lim Wei , Shi Qianqian , Wang Yan , Bay Johanis Aryo P. B. , Lai Daniel T. H. , Uddin Hemayet , Cheng Wenlong
Published: May 2016

Transparent electrodes simultaneously require high electrical conductivity and high optical transparency, which have been achieved with mesh metal structures. However, most currently fabricated micro‐ and nanoelectronic devices are produced via top‐down lithography methods. Here, a bottom‐up self‐assembly approach to fabricate mesh electrode using ultrathin gold nanowires (AuNWs) at the air/water interface is reported. Slow partial ligand removal during the aging process is the key for the formation of such self‐assembled mesh structures. The resulting mesh film has a typical mesh pore size of 8–52 μm, with a sheet resistance of ≈40 times smaller than our previously reported nonmeshed AuNWs electrodes under similar optical transmittance. Our self‐assembled mesh electrodes are mechanically flexible, easily transferrable to a variety of substrates, and also patternable by marker pen lithography or cutting machine lithography, and washable, and can be directly used for touch screen and flexible interconnects for light‐emitting devices. The entire fabrication process is under ambient conditions without the need for any special equipment. These attributes indicate the potential applications of self‐assembled gold mesh electrodes in flexible solar cells, touch screen displays, and wearable electronics.
Optimization models for planning shale gas well refracture treatments
Authors: Cafaro Diego C. , Drouven Markus G. , Grossmann Ignacio E.
Published: May 2016

Refracturing is a promising option for addressing the characteristically steep decline curves of shale gas wells. In this work we propose two optimization models to address the refracturing planning problem. First, we present a continuous‐time nonlinear programming model based on a novel forecast function that predicts pre‐ and post‐treatment productivity declines. Next, we propose a discrete‐time, multi‐period mixed‐integer linear programming (MILP) model that explicitly accounts for the possibility of multiple refracture treatments over the lifespan of a well. In an attempt to reduce solution times to a minimum, we compare three alternative formulations against each other (big‐M formulation, disjunctive formulation using Standard and Compact Hull‐Reformulations) and find that the disjunctive models yield the best computational performance. Finally, we apply the proposed MILP model to two case studies to demonstrate how refracturing can increase the expected recovery of a well and improve its profitability by several hundred thousand USD. © 2016 American Institute of Chemical Engineers AIChE J, 62: 4297–4307, 2016
Trifluoromethylation of Arylsilanes with [(phen)CuCF3]
Authors: Morstein Johannes , Hou Haiyun , Cheng Chen , Hartwig John F.
Published: May 2016

A method for the trifluoromethylation of arylsilanes is reported. The reaction proceeds with [(phen)CuCF3] as the CF3 source under mild, oxidative conditions with high functional‐group compatibility. This transformation complements prior trifluoromethylation of arenes in several ways. Most important, this method converts arylsilanes formed by the silylation of aryl C−H bonds to trifluoromethylarenes, thereby allowing the conversion of arenes to trifluoromethylarenes. The unique capabilities of the reported method are demonstrated by the conversion of a C−H bond into a C−CF3 bond in active pharmaceutical ingredients which do not undergo this overall transformation by alternative functionalization processes, including a combination of borylation and trifluoromethylation.
Synthesis of α‐alkenyl‐β‐hydroxy adducts by α‐addition of unprotected 4‐bromocrotonic acid and amides with aldehydes and ketones by chromium(II)‐mediated reactions
Authors: Wessjohann Ludger A. , Wild Harry , Ferreira Leonildo A. , Schrekker Henri S.
Published: May 2016

The regioselective and diastereoselective chromium(II)‐mediated reactions of 4‐bromocrotonic acid or amides with aldehydes and ketones can proceed without the need to protect protic sites to generate the respective α‐alkenyl‐β‐hydroxy adducts, i.e. formally the addition of the α‐anion of a carboxylic acid or amide to an oxo‐compound is featured. Copyright © 2016 John Wiley & Sons, Ltd.
Effective catalytic oxidation of alcohols and alkenes with monomeric versus dimeric manganese(II) catalysts and t‐BuOOH
Authors: Kani Ibrahim , Bolat Serkan
Published: May 2016

Two new Mn(II) complexes, [Mn(C6H5COO)(H2O)(phen)2](ClO4)(CH3OH) (1) and [Mn2(μ‐C6H5COO)2(bipy)4]⋅2(ClO4) (2) (phen = 1,10‐phenanthroline; bipy = 2,2′‐bipyridine), were synthesized and characterized using UV–visible and infrared spectroscopies and single‐crystal X‐ray diffraction analyses. Complexes 1 and 2 have six‐coordinate octahedral geometry around the Mn(II) centre. Complex 1 is a monomer and consists of a deprotonated monodentate benzoate ligand together with two neutral bidentate amine ligands (phen) and a water molecule. Complex 2 has a dinuclear structure in which two Mn(II) ions share two carboxylate groups, adopting a two‐atom bridging mode, and two chelated bipy ligands. Both complexes catalyse the oxidation of alcohols and alkenes in a homogeneous catalytic system consisting of the Mn(II) complex and tert‐butyl hydroperoxide (TBHP) in acetonitrile. The system yields good to quantitative conversions of various alkenes and alcohols, such as styrene, ethylbenzene and cyclohexene to their corresponding ketones, and primary alcohols and 1‐octanol, 1‐heptanol, cyclohexanol, benzyl alcohols and cinnamyl alcohol to their corresponding aldehydes and carboxylic acids. Complexes 1 and 2 exhibit very high activity in the oxidation of cyclohexene to cyclohexanone (ca 80% selectivity) as the main product (ca 94% conversion in 1 h) and of cinnamyl alcohol to cinnamaldehyde (ca 64% selectivity) as the main product (ca 100% conversion in 0.5 h) with TBHP at 70°C in acetonitrile. In addition, optimum reaction conditions were also determined for benzyl alcohol with complexes 1 and 2 and TBHP. Copyright © 2016 John Wiley & Sons, Ltd.
Effect of crosslinking procedure on structural, thermal, and functional performances of cellulosic nanofibers: A comparison between chemical and photochemical crosslinking
Authors: Khorshidi Sajedeh , Solouk Atefeh , Karkhaneh Akbar , Mirzadeh Hamid , Sharifi Shahriar , Mazinani Saeedeh
Published: May 2016

In the current study, hydroxyethyl cellulose (HEC) based nanofibers were fabricated through electrospinning and then made water insoluble by chemical and photochemical crosslinking. Structural, thermal, and functional performances of electrospun fibers before and after crosslinking were fully assessed by a numerous techniques including microscopy, porosimetry, mechanical analysis, and cell culture study. Both crosslinking procures were found to able to preserve fibrous structure in an aqueous environment for short times, however; chemical process conferred better long‐term morphological stability and cell compatibility. These findings suggest that chemically crosslinked HEC mats may perform as a promising electrospun tissue engineering scaffold. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43832.