bluuebunny/crossref_metadata_2025 huggingface dataset:
Molecular dynamics simulations of graphoepitaxy of organic semiconductors, sexithiophene, and pentacene: Molecular-scale mechanisms of organic graphoepitaxy
Authors: Ikeda Susumu
Published: January 2018

Molecular dynamics (MD) simulations of the organic semiconductors α-sexithiophene (6T) and pentacene were carried out to clarify the mechanism of organic graphoepitaxy at the molecular level. First, the models of the grooved substrates were made and the surfaces of the inside of the grooves were modified with –OH or –OSi(CH3)3, making the surfaces hydrophilic or hydrophobic. By the MD simulations of 6T, it was found that three stable azimuthal directions exist (0, ∼45, and 90°; the angle that the c-axis makes with the groove), being consistent with experimental results. MD simulations of deposition processes of 6T and pentacene were also carried out, and pentacene molecules showed the spontaneous formation of herringbone packing during deposition. Some pentacene molecules stood on the surface and formed a cluster whose a-axis was parallel to the groove. It is expected that a deep understanding of the molecular-scale mechanisms will lead graphoepitaxy to practical applications, improving the performance of organic devices.
Activities concentration of radiocesium in wild mushroom collected in Ukraine 30 years after the Chernobyl power plant accident
Authors: Orita Makiko , Kimura Yuko , Taira Yasuyuki , Fukuda Toshiki , Takahashi Jumpei , Gutevych Oleksandr , Chornyi Serghii , Kudo Takashi , Yamashita Shunichi , Takamura Noboru
Published: January 2018

Mushrooms are recognized as one of the main contributors to internal radiation exposure from the activity concentration of radiocesium released by the accident at the Chernobyl nuclear power plant (CNNP). We evaluated the activity concentrations of the artificial radionuclides (radiocesium) in wild mushrooms collected in 2015 from Korosten and Lugine, Zhitomir region, Ukraine, located 120 km away from the CNPP. Cesium-137 was detected in 110 of 127 mushroom samples (86.6%). Based on the average mushroom consumption (5 kg per year), we calculated committed effective doses ranging from 0.001–0.12 mSv. Cesium-137 remains in the wild mushrooms even 30 years after the accident, but the committed effective doses are limited by the amount of contaminated mushrooms consumed. However, evaluation of internal radiation exposure and assessment of environmental radioactivity in the surrounding area affected by the nuclear accident are still necessary in order to relieve anxiety about internal radiation exposure, as long as the possibility of consumption of contaminated mushrooms remains.
The Benefit of Ultrasound in Deciding Between Tube Thoracostomy and Observative Management in Hemothorax Resulting from Blunt Chest Trauma
Authors: Chung Meng‐Hsuan , Hsiao Chen‐Yuan , Nian Nai‐Shin , Chen Yen‐Chia , Wang Chien‐Ying , Wen Yi‐Szu , Shih Hsin‐Chin , Yen David Hung‐Tsang
Published: January 2018

Background

Hemothorax is most commonly resulted from a closed chest trauma, while a tube thoracostomy (TT) is usually the first procedure attempted to treat it. However, TT may lead to unexpected results and complications in some cases. The advantage of thoracic ultrasound (TUS) over a physical examination combined with chest radiograph (CXR) for diagnosing hemothorax1 has been proposed previously. However, its benefits in terms of avoiding non‐therapeutic TT have not yet been confirmed. Therefore, this study is aimed to evaluate the severity of hemothorax in blunt chest trauma patients by using TUS in order to avoid non‐therapeutic TT in stable cases.

Methods

The data from 46,036 consecutive patient visits to our trauma center over a four‐year period were collected, and those with blunt chest trauma were identified. Patients who met any of the following criteria were excluded: transferred from another facility, with an abbreviated injury scale (AIS) score ≥ 2 for any region except the chest region, with a documented finding of tension pneumothorax or pneumothorax >10%, younger than 16 years old and with indications requiring any non‐thoracic major operation. The decision to perform TT for those patients in the non‐TUS group was made on the basis of CXR findings and clinical symptoms. The continuous data were analyzed by using the two‐tailed Student’s t test, and the discrete data were analyzed by Chi‐square test.

Results

A total of 84 patients met the criteria for inclusion in the final analysis, with TT having been performed on 42 (50%) of those patients. The mean volume of the drainage amount was 860 ml after TT. The TT drainage was less than 500 ml in 12 patients in the non‐TUS group (40%), while none was less than 500 ml in the TUS group (p = 0.036, Fisher’s exact test). In terms of the positive rate of subsequent effective TT, the sensitivity of TUS was 90% and the specificity was 100%. There were 3 patients with delayed hemothorax: 2 of the 58 (3.6%) in the non‐TUS group and 1 of 26 (4.5%) in the TUS group (p > 0.05, Fisher’s exact test). The hospital length of stay in the non‐TUS group with non‐therapeutic TT was significantly longer than in the TUS group without TT (8.2 vs. 5.4 days, p = 0.018). There were no other major complications or deaths in either group during the 90‐day follow‐up period.

Conclusion

In the case of blunt trauma, TUS can rapidly and accurately evaluate hemothorax to avoid TT in patients who may not benefit much from it. As a result, the rate of non‐therapeutic TT can be decreased, and the influence on shortening hospital length of stay may be further evaluated with prospective controlled study.
Cognitive load predicts point-of-care ultrasound simulator performance
Authors: Aldekhyl Sara , Cavalcanti Rodrigo B. , Naismith Laura M.
Published: January 2018

Introduction The ability to maintain good performance with low cognitive load is an important marker of expertise. Incorporating cognitive load measurements in the context of simulation training may help to inform judgements of competence. This exploratory study investigated relationships between demographic markers of expertise, cognitive load measures, and simulator performance in the context of point-of-care ultrasonography.

Methods Twenty-nine medical trainees and clinicians at the University of Toronto with a range of clinical ultrasound experience were recruited. Participants answered a demographic questionnaire then used an ultrasound simulator to perform targeted scanning tasks based on clinical vignettes. Participants were scored on their ability to both acquire and interpret ultrasound images. Cognitive load measures included participant self-report, eye-based physiological indices, and behavioural measures. Data were analyzed using a multilevel linear modelling approach, wherein observations were clustered by participants.

Results Experienced participants outperformed novice participants on ultrasound image acquisition. Ultrasound image interpretation was comparable between the two groups. Ultrasound image acquisition performance was predicted by level of training, prior ultrasound training, and cognitive load. There was significant convergence between cognitive load measurement techniques. A marginal model of ultrasound image acquisition performance including prior ultrasound training and cognitive load as fixed effects provided the best overall fit for the observed data.

Discussion In this proof-of-principle study, the combination of demographic and cognitive load measures provided more sensitive metrics to predict ultrasound simulator performance.
Measuring cognitive load
Authors: Sweller John
Published: January 2018

None
Medical students are not blank slates: Positionality and curriculum interact to develop professional identity
Authors: Fergus Kirkpatrick B. , Teale Bronte , Sivapragasam Milani , Mesina Omar , Stergiopoulos Erene
Published: January 2018

None
Insight into tribological problems of green ship and corresponding research progresses
Authors: Sun Yuwei , Yan Xinping , Yuan Chengqing , Bai Xiuqin
Published: January 2018

The so-called “green ship” is being regarded as a potential solution to the problems that the shipping industry faces, such as energy conservation and environmental protection. Some new features, such as integrated renewable energy application, biomimetic materials, and antifriction and wear resistant coating have been accepted as the typical characteristics of a green ship, but the tribology problems involved in these domains have not been precisely redefined yet. Further, the related research work is generally focused on the technology or material itself, but not on the integration of the applicable object or green ship, marine environment, and tribological systematical analysis from the viewpoint of the energy efficiency design index (EEDI) and ship energy efficiency management plan (SEEMP) improvements. Aiming at the tribology problems of the green ship, this paper reviews the research status of this issue from three specific domains, which are the tribology problems of the renewable energy system, tribological research for hull resistance reduction, and energy efficiency enhancement. Some typical tribological problems in the sail‐auxiliary system are discussed, along with the solar photovoltaic system and hull drag reduction in traditional marine mechanical equipment. Correspondingly, four domains that should be further considered for the future development target of the green ship are prospected.
A robust single and multiple moving object detection, tracking and classification
Authors: Mahalingam T. , Subramoniam M.
Published: January 2018

Surveillance is the emerging concept in the current technology, as it plays a vital role in monitoring keen activities at the nooks and corner of the world. Among which moving object identifying and tracking by means of computer vision techniques is the major part in surveillance. If we consider moving object detection in video analysis is the initial step among the various computer applications. The main drawbacks of the existing object tracking method is a time-consuming approach if the video contains a high volume of information. There arise certain issues in choosing the optimum tracking technique for this huge volume of data. Further, the situation becomes worse when the tracked object varies orientation over time and also it is difficult to predict multiple objects at the same time. In order to overcome these issues here, we have intended to propose an effective method for object detection and movement tracking. In this paper, we proposed robust video object detection and tracking technique. The proposed technique is divided into three phases namely detection phase, tracking phase and evaluation phase in which detection phase contains Foreground segmentation and Noise reduction. Mixture of Adaptive Gaussian (MoAG) model is proposed to achieve the efficient foreground segmentation. In addition to it the fuzzy morphological filter model is implemented for removing the noise present in the foreground segmented frames. Moving object tracking is achieved by the blob detection which comes under tracking phase. Finally, the evaluation phase has feature extraction and classification. Texture based and quality based features are extracted from the processed frames which is given for classification. For classification we are using J48 ie, decision tree based classifier. The performance of the proposed technique is analyzed with existing techniques k-NN and MLP in terms of precision, recall, f-measure and ROC.
Avaliação da reprodutibilidade da classificação de Dejour para instabilidade femoropatelar
Authors: Mousinho Rodrigo de Souza Mendes Santiago , Ribeiro José Neias Araújo , Pedrosa Francisco Kartney Sarmento , Lima Diego Ariel de , Gonçalves Romeu Krause , Leite José Alberto Dias
Published: January 2018

Objetivo Avaliar, pela reprodutibilidade interobservador e intraobservador, a classificação proposta por David Dejour para descrever a displasia troclear do joelho.

Métodos Foram estudados dez pacientes com diagnóstico de displasia troclear. Três médicos membros da Sociedade Brasileira de Cirurgia do Joelho foram convidados para avaliar as imagens. Análises intra- e interobservador foram feitas com intervalo de uma semana. A reprodutibilidade foi avaliada em quatro cenários: uso de radiografia; uso de radiografia e tomografia; uso de radiografia, consultando-se a classificação no momento; e uso de radiografia e tomografia, consultando-se a classificação no momento.

Resultados A avaliação intraobservador apresentou resultados discordantes. Na análise interobservador, o grau de concordância foi baixo para as análises que usavam apenas a radiografia e excelente para aquelas que associavam radiografia e tomografia.

Conclusão A classificação de Dejour apresentou uma baixa reprodutibilidade intra e interobservador quando usada somente a radiografia em perfil. Demonstrou-se que o uso apenas da radiografia para classificar pode gerar falta de uniformidade até mesmo entre observadores experientes. Contudo, quando radiografia e tomografia foram associadas, a reprodutibilidade melhorou.
A ‘Shaftesburian Agenda’? Lord Burlington, Lord Shaftesbury and the Intellectual Origins of English Palladianism
Authors: Echlin Alexander , Kelley William
Published: January 2018

In this article we argue against the widely held view that Lord Burlington's love for architecture was inspired by the writings of the third Earl of Shaftesbury, particularly his Letter Concerning Design. First, we seek to demonstrate that Burlington could not have been familiar with, or even aware of, Shaftesbury's Letter until long after the development of his interest in architecture. Secondly, we argue that Shaftesbury's true architectural heirs advanced an agenda that was distinct from, and even hostile to, Burlingtonian Palladianism; and that the supposed link between the Letter and Burlington has served to distract historians from this. We suggest, thirdly, that the importance assigned to the Letter by architectural historians has derived from a longstanding and hugely influential interpretation of the rise of Burlingtonian Palladianism, an interpretation undermined by much recent work by revisionist architectural historians but still prevalent. Finally, having argued against the link between Shaftesbury and Burlington, we posit an alternative source for Burlingtonian Palladianism.
The Dynamic of Design: ‘Source’ Buildings and Contract Making in England in the Later Middle Ages
Authors: Byng Gabriel
Published: January 2018

Art historians usually find little evidence for the nature of communication between patrons and architects in the Middle Ages. Scholarly opinion has often placed the burden of new design with masons, but over the course of the later twentieth century this claim has been revised and nuanced. This paper uses the evidence of wills and contracts in order to answer two questions: what techniques did medieval patrons use to describe their wishes to their masons; and how prescriptive were their requirements? Its conclusions suggest that patrons, even of local or parochial projects, could make highly specific and creative demands for new works, based on critical and perceptive judgements of recently constructed buildings in their local area. It recreates the discursive and disputatious design process adopted in several parishes as they planned, contracted and executed new church buildings.
Conception and Construction: Galeazzo Alessi and the Use of Drawings in Sixteenth-Century Architectural Practice
Authors: Gill Rebecca M.
Published: January 2018

This article examines drawings associated with the sixteenth-century Italian architect, Galeazzo Alessi, focusing primarily on two important collections: the 112 folios held in the Biblioteca Ambrosiana in Milan for the Milanese church of S. Maria presso S. Celso and the so-called Libro dei Misteri in Varallo's Biblioteca Civica, which contains 318 drawings for the pilgrimage site of the Sacro Monte there. By comparing Alessi's handwriting and drawing style across a variety of different letters and drawings present in archives in Genoa, Milan and Varallo, it is argued that all the drawings held in the Biblioteca Ambrosiana folder and in the Libro dei Misteri must be the work of Alessi himself. The article then moves on to a discussion of Alessi's use of drawings in his practice and the developing role of the architect in the sixteenth century , which, it is argued, was increasingly defined by the ability of the architect to invent and to draw rather than to build.
Stones of Science: Charles Harriot Smith and the Importance of Geology in Architecture, 1834–64
Authors: Gillin Edward John
Published: January 2018

In mid nineteenth-century Britain, the study of geology involved radical new understandings of the earth's history. This had ramifications for architecture, providing new ways of seeing stone and designing buildings. This article examines the works of stone-mason Charles Smith. Following the destruction of the Houses of Parliament in 1834, the government initiated a national survey to select a stone for Britain's new legislature. Alongside geologists Henry De la Beche and William Smith, Charles Smith toured the buildings and quarries of Britain, producing a report that was intended to guide not only the choice of stone at Westminster, but all future architectural projects. He spent the following two decades promoting geological knowledge for architectural work. His reading of texts that examined the earth's geological formation, such as Charles Lyell's, shaped new understandings of stone and cement. This article demonstrates how, in a rapidly industrialising society, geology and architecture became increasingly inseparable.
The Rhetoric of Fictive Architecture:CopiaandAmplificatioin Altichiero Da Zevio's Paintings at the Oratory of St George in Padua
Authors: Lupi Livia
Published: January 2018

This article examines the relationship between architecture in painting and rhetorical theory, proposing that fictive buildings are often a powerful form of visual rhetoric aiming to entice the viewer and showcase the artist's skill. Illustrating the potential of a rhetorical approach for the interpretation of architecture more widely, the article focuses on Altichiero da Zevio's fresco cycle in the Oratory of St George in Padua (c.1379–84), suggesting that his structurally inventive and intricately decorated architectural settings can be interpreted through the rhetorical tropescopiaandamplificatio. It argues that fourteenth-century Padua was an environment particularly receptive to rhetorical theory, and suggests that viewers would have experienced Altichiero's fictive buildings as a visual equivalent of the persuasive strategies employed in contemporary textual composition. The analysis highlights the rhetorical messages of architectural forms, underscoring the porosity between two and three-dimensional buildings for a more integrated consideration of architecture and its communicative powers.
The Rise and Fall of Cork Model Collections in Britain
Authors: Gillespie Richard
Published: January 2018

Commencing in the late 1760s, cork models of classical monuments in Italy were purchased by wealthy British collectors while on their Grand Tour. Initially commissioned by tourists with specific antiquarian and architectural interests, the models were an expression of the collector's knowledge of classical history and of their Neoclassical sensibility. Models soon appeared in the Society of Antiquaries of London and the British Museum, in the private displays of Charles Townley and John Stuart, Earl of Bute, and in George III's royal collection. In the early 1800s, architect John Soane began purchasing models from the secondary market for his house museum. Interest in cork architectural models waned during the Nineteenth Century. Descendants of the original owners transferred them to public institutions, while museums that had at first enthusiastically welcomed the donations or made their own purchases, relegated the models to storage. In the twentieth century the majority of the models were discarded or lost. This paper explores the reasons for the enthusiastic acquisition of architectural cork models and their subsequent demise.
Relations and Reflections to the Eye and Understanding: Architectural Models and the Rebuilding of the Royal Exchange, 1839–44
Authors: Wells M. J.
Published: January 2018

Historians have overlooked the ways in which architects perceived and used models during the nineteenth century. Drawing on a wide range of documentary sources, as well as drawings, prints and a surviving model, this essay examines how architectural models were deployed in the competition for the Royal Exchange and its design and construction (1839–44). Many figures saw models as important arbiters in choosing designs and, after the initial competition process, C.R. Cockerell and William Tite demonstrated the use of models as poetic and rhetoric tools in architectural practice. Drawing especially on the example of Tite's model of the Royal Exchange portico, which survives at the Victoria & Albert Museum, the essay discusses how architectural models played an important role in the social activities surrounding the profession including ceremonial events,conversazioniand international exhibitions.
On the propagation of acoustic–gravity waves under elastic ice sheets
Authors: Abdolali Ali , Kadri Usama , Parsons Wade , Kirby James T.
Published: January 2018

The propagation of wave disturbances in water of varying depth bounded above by ice sheets is discussed, accounting for gravity, compressibility and elasticity effects. Considering the more realistic scenario of elastic ice sheets reveals a continuous spectrum of acoustic–gravity modes that propagate even below the cutoff frequency of the rigid surface solution where surface (gravity) waves cannot exist. The balance between gravitational forces and oscillations in the ice sheet defines a new dimensionless quantity $\mathfrak{Ka}$. When the ice sheet is relatively thin and the prescribed frequency is relatively low ($\mathfrak{Ka}\ll 1$), the free-surface bottom-pressure solution is retrieved in full. However, thicker ice sheets or propagation of relatively higher frequency modes ($\mathfrak{Ka}\gg 1$) alter the solution fundamentally, which is reflected in an amplified asymmetric signature and different characteristics of the eigenvalues, such that the bottom pressure is amplified when acoustic–gravity waves are transmitted to shallower waters. To analyse these scenarios, an analytical solution and a depth-integrated equation are derived for the cases of constant and varying depths, respectively. Together, these are capable of modelling realistic ocean geometries and an inhomogeneous distribution of ice sheets.
Free-stream coherent structures in a planar jet
Authors: Deguchi Kengo , Hall Philip
Published: January 2018

The free-stream coherent structure theory developed by Deguchi & Hall (J. Fluid Mech., vol. 752, 2014, pp. 602–625), valid in the large-Reynolds-number asymptotic limit, is extended and applied to jet flows. It is shown that a nonlinear exact coherent structure can be supported at the edge of the jet, and the structure induces a much bigger streaky flow in the centre of the jet. The lambda-shaped vortices that characterise the coherent structure are qualitatively consistent with those seen in experimental observations. Here a planar incompressible jet is investigated for the sake of simplicity, but the structure we describe could be used as a basis of more complex theories for incompressible and compressible jets of practical importance.
Bounds on heat transfer for Bénard–Marangoni convection at infinite Prandtl number
Authors: Fantuzzi Giovanni , Pershin Anton , Wynn Andrew
Published: January 2018

The vertical heat transfer in Bénard–Marangoni convection of a fluid layer with infinite Prandtl number is studied by means of upper bounds on the Nusselt number $Nu$ as a function of the Marangoni number $Ma$. Using the background method for the temperature field, it has recently been proved by Hagstrom & Doering (Phys. Rev. E, vol. 81, 2010, art. 047301) that $Nu\leqslant 0.838Ma^{2/7}$. In this work we extend previous background method analysis to include balance parameters and derive a variational principle for the bound on $Nu$, expressed in terms of a scaled background field, that yields a better bound than Hagstrom & Doering’s formulation at a given $Ma$. Using a piecewise-linear, monotonically decreasing profile we then show that $Nu\leqslant 0.803Ma^{2/7}$, lowering the previous prefactor by 4.2 %. However, we also demonstrate that optimisation of the balance parameters does not affect the asymptotic scaling of the optimal bound achievable with Hagstrom & Doering’s original formulation. We subsequently utilise convex optimisation to optimise the bound on $Nu$ over all admissible background fields, as well as over two smaller families of profiles constrained by monotonicity and convexity. The results show that $Nu\leqslant O(Ma^{2/7}(\ln Ma)^{-1/2})$ when the background field has a non-monotonic boundary layer near the surface, while a power-law bound with exponent $2/7$ is optimal within the class of monotonic background fields. Further analysis of our upper-bounding principle reveals the role of non-monotonicity, and how it may be exploited in a rigorous mathematical argument.
Inclined porous medium convection at large Rayleigh number
Authors: Wen Baole , Chini Gregory P.
Published: January 2018

High-Rayleigh-number ($Ra$) convection in an inclined two-dimensional porous layer is investigated using direct numerical simulations (DNS) and stability and variational upper-bound analyses. When the inclination angle $\unicode[STIX]{x1D719}$ of the layer satisfies $0^{\circ }<\unicode[STIX]{x1D719}\lesssim 25^{\circ }$, DNS confirm that the flow exhibits a three-region wall-normal asymptotic structure in accord with the strictly horizontal ($\unicode[STIX]{x1D719}=0^{\circ }$) case, except that as $\unicode[STIX]{x1D719}$ is increased the time-mean spacing between neighbouring interior plumes also increases substantially. Both DNS and upper-bound analysis indicate that the heat transport enhancement factor (i.e. the Nusselt number) $Nu\sim CRa$ with a $\unicode[STIX]{x1D719}$-dependent prefactor $C$. When $\unicode[STIX]{x1D719}>\unicode[STIX]{x1D719}_{t}$, however, where $30^{\circ }<\unicode[STIX]{x1D719}_{t}<32^{\circ }$ independently of $Ra$, the columnar flow structure is completely broken down: the flow transitions to a large-scale travelling-wave convective roll state, and the heat transport is significantly reduced. To better understand the physics of inclined porous medium convection at large $Ra$ and modest inclination angles, a spatial Floquet analysis is performed, yielding predictions of the linear stability of numerically computed, fully nonlinear steady convective states. The results show that there exist two types of instability when $\unicode[STIX]{x1D719}\neq 0^{\circ }$: a bulk-mode instability and a wall-mode instability, consistent with previous findings for $\unicode[STIX]{x1D719}=0^{\circ }$ (Wen et al., J. Fluid Mech., vol. 772, 2015, pp. 197–224). The background flow induced by the inclination of the layer intensifies the bulk-mode instability during its subsequent nonlinear evolution, thereby favouring increased spacing between the interior plumes relative to that observed in convection in a horizontal porous layer.
A parallel stability analysis of a trailing vortex wake
Authors: Edstrand Adam M. , Schmid Peter J. , Taira Kunihiko , Cattafesta Louis N.
Published: January 2018

Trailing vortices are generated in aeronautical and maritime applications and produce a variety of adverse effects that remain difficult to control. A stability analysis can direct flow control designers towards pertinent frequencies, wavelengths and locations that may lead to the excitation of instabilities, resulting in the eventual breakup of the vortex. Most models for trailing vortices, however, are far-field models, making implementation of the findings from stability analyses challenging. As such, we perform a stability analysis in the formative region where the numerically computed base flow contains both a two-dimensional wake and a tip vortex generated from a NACA0012 at a$5^{\circ }$angle of attack and a chord-based Reynolds number of$Re_{c}=1000$. The parallel temporal and spatial analyses show that at three chord lengths downstream of the trailing edge, seven unstable modes are present: three stemming from the temporal analysis and four arising in the spatial analysis. The three temporal instabilities are analogues to three unstable modes in the spatial analysis, with the wake instability dominating in both analyses. The helical mode localized to the vortex co-rotates with the base flow, which is converse with the counter-rotating$m=-1$instabilities of a Batchelor vortex model, which may be a result of the formative nature of the base-flow vortex. The fourth spatial mode is localized to the tip vortex region. The continuous part of the spectrum contains oscillatory and wavepacket solutions prompting the utilization of a wavepacket analysis to analyse the flow field and group velocity. The structure and details of the full bi-global spectrum will help navigate the design space of effective control strategies to hasten decay of persistent wingtip vortices.
Impact of domain anisotropy on the inverse cascade in geostrophic turbulent convection
Authors: Julien Keith , Knobloch Edgar , Plumley Meredith
Published: January 2018

The effect of domain anisotropy on the inverse cascade occurring within the geostrophic turbulence regime of rapidly rotating Rayleigh–Bénard convection is investigated. In periodic domains with square cross-section in the horizontal, a domain-filling dipole state is present. For rectangular periodic domains, a Kolmogorov-like flow parallel to the short side and consisting of a periodic array of alternating unidirectional jets with embedded vortices is observed, together with an underlying weak meandering transverse jet. Similar transitions occurring in weakly dissipative two-dimensional flows driven by externally imposed small-amplitude noise and in classical hydrostatic geostrophic turbulence are a consequence of inviscid conservation of energy and potential enstrophy, and can be understood using statistical mechanics considerations. Rotating Rayleigh–Bénard convection represents an important three-dimensional system with only one inviscid invariant which nonetheless exhibits large-scale structures driven by intrinsically generated fluctuations.
Bounds for Rayleigh–Bénard convection between free-slip boundaries with an imposed heat flux
Authors: Fantuzzi Giovanni
Published: January 2018

We prove the first rigorous bound on the heat transfer for three-dimensional Rayleigh–Bénard convection of finite-Prandtl-number fluids between free-slip boundaries with an imposed heat flux. Using the auxiliary functional method with a quadratic functional, which is equivalent to the background method, we prove that the Nusselt number $\mathit{Nu}$ is bounded by $\mathit{Nu}\leqslant 0.5999\mathit{R}^{1/3}$ uniformly in the Prandtl number, where $\mathit{R}$ is the Rayleigh number based on the imposed heat flux. In terms of the Rayleigh number based on the mean vertical temperature drop, $\mathit{Ra}$, we obtain $\mathit{Nu}\leqslant 0.4646\mathit{Ra}^{1/2}$. The scaling with Rayleigh number is the same as that of bounds obtained with no-slip isothermal, free-slip isothermal and no-slip fixed-flux boundaries, and numerical optimisation of the bound suggests that it cannot be improved within our bounding framework. Contrary to the two-dimensional case, therefore, the $\mathit{Ra}$-dependence of rigorous upper bounds on the heat transfer obtained with the background method for three-dimensional Rayleigh–Bénard convection is insensitive to both the thermal and the velocity boundary conditions.
Nixoning the Moon
Authors: Brownell Kathryn Cramer
Published: January 2018

On the cratered surface of the moon, a small stainless steel plaque commemorates the remarkable visit made by “men from the planet earth” who “came in peace for all mankind” in the summer of 1969. It bears the name of the three men who made the journey, Neil Armstrong, Edwin Aldrin, and Michael Collins. And it features the name of one man who did not: President Richard M. Nixon.
The World and the Garden: Ekphrasis and “Overterritorialization” in Jamaica Kincaid’s Garden Writing
Authors: Wong Shirley Lau
Published: January 2018

The garden is often regarded as a feminine space of withdrawal. By contrast, this essay examines how Jamaica Kincaid envisions the garden not as a retreat from the world but as an opportunity to delve into the colonial histories of plants. Kincaid traces the twinned histories of botany and empire, highlighting how the botanic garden served as a laboratory for the development of plantation crops and therefore played a pivotal role in imperial and capitalist expansion. I concentrate on Kincaid’s use of ekphrasis, which reveals the many aesthetic, scientific, and colonial discourses that construct the garden as a both discursive and material space. Kincaid’s ekphrastic prose produces an effect of “overterritorialization,” in which loco-descriptive details do not provide the reader with a sense of place; rather, the overabundance of details overwhelms and even unsettles the reader. Kincaid’s garden writing thus shows us an alternative model of reading postcolonial environmental literature.
Creativity and the Governance of Universities: Encounters of the Third Kind
Authors: Drori Gili S.
Published: January 2018

Discussions of creativity and university governance often conflate multiple kinds of creativity–governance relations. Focusing on the ‘third kind’ of creativity–governance relations in universities, I discuss the role of creativity in prospecting governance models. In other words, this paper focuses on the methods forcreativelyseeking (third kind)creativegovernance models (second kind) that foster academiccreativity(first kind). I argue that the methods of prospecting governance models are subject to institutional dynamics that steer such search off the path of creativity. I note in particular two such institutional dynamics that track the prospecting process – namely, professional expertise and referentiality – and I argue that these institutional dynamics generate inherent tension in the governance of creativity in universities. I illustrate these claims with findings from a large-scope research project on the branding of universities.
Klinische und psychosoziale Charakteristika bei Suchtpatienten mit und ohne PTBS
Authors: Hildebrand Anja , Vollmer Heinz C. , Domma-Reichart Julia
Published: January 2018

Zusammenfassung. Hintergrund: In Deutschland liegen nur vereinzelte Studien zur PTBS-Prävalenzquote bei Suchtpatienten und zu deren psychischen Befund vor. Fragestellung: Wie hoch ist die relative Häufigkeit einer PTBS bei Patienten mit substanzbezogenen Störungen und wie unterscheiden sich die Patienten mit und ohne PTBS hinsichtlich klinischer und psychosozialer Charakteristika? Methode: Mittels Chi-Quadrat- und t-Tests wurden 376 mittels Propensity Scores gematchte Patienten aus einer Stichprobe von 4105 konsekutiv aufgenommenen Abhängigen in diagnostischen und psychischen Merkmalen retrospektiv miteinander verglichen. Ergebnisse: Die relative Häufigkeit von PTBS lag bei den Patienten mit einer alkoholbezogenen Störung bei 3,8 %, bei den restlichen Suchtpatienten mit Störungen durch andere psychotrope Substanzen bei 10,5 %. Bei den PTBS Patienten lag häufiger eine Persönlichkeitsstörung vor. Außerdem waren die PTBS Patienten stärker psychisch belastet, in ihrem Interaktionsstil abweisender, introvertierter, und nachgiebiger sowie im Bindungsstil vermeidender. Schlussfolgerungen: Die Unterschiede verdeutlichen die Notwendigkeit von auf den Interaktions- und Bindungsstil individuell angepassten Interventionen im Rahmen der Standardbehandlungen für Suchtpatienten mit PTBS.
Forschungstransparenz als hohes wissenschaftliches Gut stärken
Authors: Schönbrodt Felix D. , Maier Markus , Heene Moritz , Bühner Markus
Published: January 2018

Zusammenfassung. Groß angelegte Replikationsprojekte der letzten Jahre legen ein aus unserer Sicht beunruhigendes Ausmaß an nicht-replizierbaren Befunden in der wissenschaftlichen Literatur nahe, sowohl in der Psychologie als auch in anderen Disziplinen. Basierend auf einer Analyse einiger Ursachen dieser Situation argumentieren wir, dass der Wandel hin zu einer offenen Wissenschaft („Open Science“) eine Konsequenz aus der Glaubwürdigkeitskrise sein muss. Wir plädieren für konkrete und machbare Änderungen in den Arbeitseinheiten und Instituten vor Ort, und zeigen exemplarisch, welche Schritte am Department Psychologie der Ludwig-Maximilians-Universität München umgesetzt wurden. Diese Schritte betreffen Anreizstrukturen, die Forschungskultur, die Lehre und die Verzahnung mit der Ethikkommission. Sie haben das Ziel, eine reproduzierbarere und glaubwürdigere Forschung zu unterstützen, ohne unnötige bürokratische Belastungen zu erzeugen.
Tracing Electric Currents That Flow Along Earth’s Magnetic Field
Authors: Witman Sarah
Published: January 2018

A new study uses satellite data to examine a worldwide system of electric currents in greater detail than ever before.
Corn’s Ancestor Could Help It Go Green
Authors: Fox Alex
Published: January 2018

The grandfather of modern corn may hold the key to reducing its need for chemical fertilizers.
Impact on short-lived climate forcers increases projected warming due to deforestation
Authors: Scott C. E. , Monks S. A. , Spracklen D. V. , Arnold S. R. , Forster P. M. , Rap A. , Äijälä M. , Artaxo P. , Carslaw K. S. , Chipperfield M. P. , Ehn M. , Gilardoni S. , Heikkinen L. , Kulmala M. , Petäjä T. , Reddington C. L. S. , Rizzo L. V. , Swietlicki E. , Vignati E. , Wilson C.
Published: January 2018

The climate impact of deforestation depends on the relative strength of several biogeochemical and biogeophysical effects. In addition to affecting the exchange of carbon dioxide (CO2) and moisture with the atmosphere and surface albedo, vegetation emits biogenic volatile organic compounds (BVOCs) that alter the formation of short-lived climate forcers (SLCFs), which include aerosol, ozone and methane. Here we show that a scenario of complete global deforestation results in a net positive radiative forcing (RF; 0.12 W m−2) from SLCFs, with the negative RF from decreases in ozone and methane concentrations partially offsetting the positive aerosol RF. Combining RFs due to CO2, surface albedo and SLCFs suggests that global deforestation could cause 0.8 K warming after 100 years, with SLCFs contributing 8% of the effect. However, deforestation as projected by the RCP8.5 scenario leads to zero net RF from SLCF, primarily due to nonlinearities in the aerosol indirect effect.
Impaired autophagy bridges lysosomal storage disease and epithelial dysfunction in the kidney
Authors: Festa Beatrice Paola , Chen Zhiyong , Berquez Marine , Debaix Huguette , Tokonami Natsuko , Prange Jenny Ann , Hoek Glenn van de , Alessio Cremonesi , Raimondi Andrea , Nevo Nathalie , Giles Rachel H. , Devuyst Olivier , Luciani Alessandro
Published: January 2018

The endolysosomal system sustains the reabsorptive activity of specialized epithelial cells. Lysosomal storage diseases such as nephropathic cystinosis cause a major dysfunction of epithelial cells lining the kidney tubule, resulting in massive losses of vital solutes in the urine. The mechanisms linking lysosomal defects and epithelial dysfunction remain unknown, preventing the development of disease-modifying therapies. Here we demonstrate, by combining genetic and pharmacologic approaches, that lysosomal dysfunction in cystinosis results in defective autophagy-mediated clearance of damaged mitochondria. This promotes the generation of oxidative stress that stimulates Gα12/Src-mediated phosphorylation of tight junction ZO-1 and triggers a signaling cascade involving ZO-1-associated Y-box factor ZONAB, which leads to cell proliferation and transport defects. Correction of the primary lysosomal defect, neutralization of mitochondrial oxidative stress, and blockage of tight junction-associated ZONAB signaling rescue the epithelial function. We suggest a link between defective lysosome-autophagy degradation pathways and epithelial dysfunction, providing new therapeutic perspectives for lysosomal storage disorders.
Wet-dry cycles enable the parallel origin of canonical and non-canonical nucleosides by continuous synthesis
Authors: Becker Sidney , Schneider Christina , Okamura Hidenori , Crisp Antony , Amatov Tynchtyk , Dejmek Milan , Carell Thomas
Published: January 2018

The molecules of life were created by a continuous physicochemical process on an early Earth. In this hadean environment, chemical transformations were driven by fluctuations of the naturally given physical parameters established for example by wet–dry cycles. These conditions might have allowed for the formation of (self)-replicating RNA as the fundamental biopolymer during chemical evolution. The question of how a complex multistep chemical synthesis of RNA building blocks was possible in such an environment remains unanswered. Here we report that geothermal fields could provide the right setup for establishing wet–dry cycles that allow for the synthesis of RNA nucleosides by continuous synthesis. Our model provides both the canonical and many ubiquitous non-canonical purine nucleosides in parallel by simple changes of physical parameters such as temperature, pH and concentration. The data show that modified nucleosides were potentially formed as competitor molecules. They could in this sense be considered as molecular fossils.
Discovery of superconductivity in quasicrystal
Authors: Kamiya K. , Takeuchi T. , Kabeya N. , Wada N. , Ishimasa T. , Ochiai A. , Deguchi K. , Imura K. , Sato N. K.
Published: January 2018

Superconductivity is ubiquitous as evidenced by the observation in many crystals including carrier-doped oxides and diamond. Amorphous solids are no exception. However, it remains to be discovered in quasicrystals, in which atoms are ordered over long distances but not in a periodically repeating arrangement. Here we report electrical resistivity, magnetization, and specific-heat measurements of Al–Zn–Mg quasicrystal, presenting convincing evidence for the emergence of bulk superconductivity at a very low transition temperature of $$T_{\rm c} \cong 0.05$$

T

c

≅
0.05
K. We also find superconductivity in its approximant crystals, structures that are periodic, but that are very similar to quasicrystals. These observations demonstrate that the effective interaction between electrons remains attractive under variation of the atomic arrangement from periodic to quasiperiodic one. The discovery of the superconducting quasicrystal, in which the fractal geometry interplays with superconductivity, opens the door to a new type of superconductivity, fractal superconductivity.
E2112: randomized phase iii trial of endocrine therapy plus entinostat/placebo in patients with hormone receptor-positive advanced breast cancer
Authors: Yeruva Sri Lakshmi Hyndavi , Zhao Fengmin , Miller Kathy D. , Tevaarwerk Amye J. , Wagner Lynne I. , Gray Robert J. , Sparano Joseph A. , Connolly Roisin M.
Published: January 2018

Endocrine therapies are effective in the treatment of hormone receptor (HR)-positive breast cancer, however, de novo or acquired treatment resistance is a significant clinical problem. A potential mechanism of resistance involves changes in gene expression secondary to epigenetic modifications, which might be reversed with the use of histone deacetylase (HDAC) inhibitors such as entinostat. The ENCORE 301 phase II randomized, placebo-controlled study demonstrated a significant improvement in progression-free survival (PFS) and overall survival (OS), with the addition of entinostat to exemestane in patients with HR-positive advanced breast cancer with disease progression after prior non-steroidal aromatase inhibitor (AI). These results prompted the development of E2112, a phase III registration trial which is investigating entinostat/placebo in combination with exemestane in patients with locally advanced or metastatic breast cancer who have experienced disease progression after a non-steroidal AI. E2112 aims to validate the preclinical and clinical findings supporting the role of HDAC inhibitors in overcoming resistance to endocrine therapy in breast cancer, and ultimately improve outcomes for patients with advanced breast cancer.
Pan-cancer screen for mutations in non-coding elements with conservation and cancer specificity reveals correlations with expression and survival
Authors: Hornshøj Henrik , Nielsen Morten Muhlig , Sinnott-Armstrong Nicholas A. , Świtnicki Michał P. , Juul Malene , Madsen Tobias , Sallari Richard , Kellis Manolis , Ørntoft Torben , Hobolth Asger , Pedersen Jakob Skou
Published: January 2018

Cancer develops by accumulation of somatic driver mutations, which impact cellular function. Mutations in non-coding regulatory regions can now be studied genome-wide and further characterized by correlation with gene expression and clinical outcome to identify driver candidates. Using a new two-stage procedure, called ncDriver, we first screened 507 ICGC whole-genomes from 10 cancer types for non-coding elements, in which mutations are both recurrent and have elevated conservation or cancer specificity. This identified 160 significant non-coding elements, including theTERTpromoter, a well-known non-coding driver element, as well as elements associated with known cancer genes and regulatory genes (e.g.,PAX5,TOX3,PCF11,MAPRE3). However, in some significant elements, mutations appear to stem from localized mutational processes rather than recurrent positive selection in some cases. To further characterize the driver potential of the identified elements and shortlist candidates, we identified elements where presence of mutations correlated significantly with expression levels (e.g.,TERTandCDH10) and survival (e.g.,CDH9andCDH10) in an independent set of 505 TCGA whole-genome samples. In a larger pan-cancer set of 4128 TCGA exomes with expression profiling, we identified mutational correlation with expression for additional elements (e.g., nearGATA3,CDC6,ZNF217, andCTCFtranscription factor binding sites). Survival analysis further pointed toMIR122, a known marker of poor prognosis in liver cancer. In conclusion, the screen for significant mutation patterns coupled with correlative mutational analysis identified new individual driver candidates and suggest that some non-coding mutations recurrently affect expression and play a role in cancer development.
Quantum logic using correlated one-dimensional quantum walks
Authors: Lahini Yoav , Steinbrecher Gregory R. , Bookatz Adam D. , Englund Dirk
Published: January 2018

Quantum Walks are unitary processes describing the evolution of an initially localized wavefunction on a lattice potential. The complexity of the dynamics increases significantly when several indistinguishable quantum walkers propagate on the same lattice simultaneously, as these develop non-trivial spatial correlations that depend on the particle’s quantum statistics, mutual interactions, initial positions, and the lattice potential. We show that even in the simplest case of a quantum walk on a one dimensional graph, these correlations can be shaped to yield a complete set of compact quantum logic operations. We provide detailed recipes for implementing quantum logic on one-dimensional quantum walks in two general cases. For non-interacting bosons—such as photons in waveguide lattices—we find high-fidelity probabilistic quantum gates that could be integrated into linear optics quantum computation schemes. For interacting quantum-walkers on a one-dimensional lattice—a situation that has recently been demonstrated using ultra-cold atoms—we find deterministic logic operations that are universal for quantum information processing. The suggested implementation requires minimal resources and a level of control that is within reach using recently demonstrated techniques. Further work is required to address error-correction.