bluuebunny/crossref_metadata_2025 huggingface dataset:
Strain‐Mediated Phase Stabilization: A New Strategy for Ultrastable α‐CsPbI3 Perovskite by Nanoconfined Growth
Authors: Ma Sunihl , Kim Seong Hun , Jeong Beomjin , Kwon Hyeok‐Chan , Yun Seong‐Cheol , Jang Gyumin , Yang Hyunha , Park Cheolmin , Lee Donghwa , Moon Jooho
Published: April 2019

All‐inorganic cesium lead triiodide (CsPbI3) perovskite is considered a promising solution‐processable semiconductor for highly stable optoelectronic and photovoltaic applications. However, despite its excellent optoelectronic properties, the phase instability of CsPbI3 poses a critical hurdle for practical application. In this study, a novel stain‐mediated phase stabilization strategy is demonstrated to significantly enhance the phase stability of cubic α‐phase CsPbI3. Careful control of the degree of spatial confinement induced by anodized aluminum oxide (AAO) templates with varying pore sizes leads to effective manipulation of the phase stability of α‐CsPbI3. The Williamson–Hall method in conjunction with density functional theory calculations clearly confirms that the strain imposed on the perovskite lattice when confined in vertically aligned nanopores can alter the formation energy of the system, stabilizing α‐CsPbI3 at room temperature. Finally, the CsPbI3 grown inside nanoporous AAO templates exhibits exceptional phase stability over three months under ambient conditions, in which the resulting light‐emitting diode reveals a natural red color emission with very narrow bandwidth (full width at half maximum of 33 nm) at 702 nm. The universally applicable template‐based stabilization strategy can give in‐depth insights on the strain‐mediated phase transition mechanism in all‐inorganic perovskites.
Spin‐Dependent Electron–Hole Recombination and Dissociation in Nonfullerene Acceptor ITIC‐Based Organic Photovoltaic Systems
Authors: Zhao Fenggui , Wang Kai , Duan Jiashun , Zhu Xixiang , Lu Kai , Zhao Chongguang , Zhang Caixia , Yu Haomiao , Hu Bin
Published: April 2019

A nonfullerene acceptor (NFA), named 3,9‐bis(2‐methylene‐(3‐(1,1‐dicyanomethylene)‐indanone))‐5,5,11,11‐tetrakis(4‐hexylphenyl)‐dithieno[2,3‐d:2′,3′‐d′]‐s‐indaceno[1,2‐b:5,6‐b′] dithiophene (ITIC) with the fused aromatic conjugated backbone structure, is an intriguing small molecular semiconductor in the application of organic bulk heterojunction (BHJ) solar cells. However, the underlying spin‐dependent photo‐physics in the photovoltaic process remains deficient. Here, ITIC‐based thin solid film, binary, and ternary organic blends are designed and fabricated with two polymeric donors, poly[(2,6‐(4,8‐bis(5‐(2‐ethylhexyl)thiophen‐2‐yl)‐benzo[1,2‐b:4,5‐b′]‐dithiophene))‐alt‐(5,5‐(1′,3′‐di‐2‐thienyl‐5′,7′‐bis(2‐ethylhexyl)benzo[1′,2′‐c:4′,5′‐c′]dithiophene‐4,8‐dione))] (PBDB‐T) and poly[(2,6‐(4,8‐Bis(3‐((2‐ethylhexyl)oxy)‐phenyl)‐benzo[1,2‐b:4,5‐b′]‐dithiophene))‐alt‐(5,5‐(1′,3′‐di‐2‐thienyl‐5′,7′‐bis(2‐ethylhexyl)benzo[1′,2′‐c:4′,5′‐c′]dithiophene‐4,8‐dione))] (PBPD‐Th). With the spin‐sensitive magneto‐photocurrent and magneto‐electroluminescence measurements, ITIC always exhibits large magnetic field effects with negative signs in the ambient temperature. The effect is attributed to the exciton‐charge reaction. However, both positive and negative signs are detected in the binary and ternary organic blends at small and large fields, respectively. The results elucidate that the mutual combination of the spin‐dependent polaron pair dissociation and exciton‐charge reaction plays a decisive role in the photovoltaic process. Furthermore, with photo‐induced electron paramagnetic resonance (EPR) studies, the full width at half maximum (FWHM) of the line shape for the positive magneto‐photocurrent is firmly associated to the magnitude of the effective g‐factor. The present study may shed a new light on the deep understanding of spin‐dependent photo‐physical process in NFA‐based solar cells for organic opto‐spintronic developments.
Impact of aerodynamic modeling on seakeeping performance of a floating horizontal axis wind turbine
Authors: Leroy Vincent , Gilloteaux Jean‐Christophe , Lynch Mattias , Babarit Aurélien , Ferrant Pierre
Published: April 2019

Over the last decade, several coupled simulation tools have been developed in order to design and optimize floating wind turbines (FWTs). In most of these tools, the aerodynamic modeling is based on quasi‐steady aerodynamic models such as the blade element momentum (BEM). It may not be accurate enough for FWTs as the motion of the platform induces highly unsteady phenomena around the rotor. To address this issue, a new design tool has been developed coupling a seakeeping solver with an unsteady aerodynamic solver based on the free vortex wake (FVW) theory. This tool is here compared with the reference code FAST, which is based on the BEM theory in order to characterize the impact of the aerodynamic model on the seakeeping of a floating horizontal axis wind turbine (HAWT). Aerodynamic solvers are compared for the case of the free floating NREL 5MW HAWT supported by the OC3Hywind SPAR. Differences obtained between the models have been analyzed through a study of the aerodynamic loads acting on the same turbine in imposed harmonic surge and pitch motions. This provides a better understanding of the intrinsic differences between the quasi‐steady and unsteady aerodynamic solvers. The study shows that differences can be observed between the three aerodynamic solvers, especially at high tip speed ratio (TSR) for which unsteady aerodynamic phenomena and complex wake dynamics occur. Observed discrepancies in the predictions of the FWT dynamic response can raise issues when designing such a system with a state‐of‐the‐art design tool.
Curvature squared invariants in six-dimensional $$ \mathcal{N} $$ = (1, 0) supergravity
Authors: Butter Daniel , Novak Joseph , Ozkan Mehmet , Pang Yi , Tartaglino-Mazzucchelli Gabriele
Published: April 2019

Abstract

We describe the supersymmetric completion of several curvature-squared invariants for $$ \mathcal{N} $$
N
= (1, 0) supergravity in six dimensions. The construction of the invariants is based on a close interplay between superconformal tensor calculus and recently developed superspace techniques to study general off-shell supergravity-matter couplings. In the case of minimal off-shell Poincaré supergravity based on the dilaton-Weyl multiplet coupled to a linear multiplet as a conformal compensator, we describe off-shell supersymmetric completions for all the three possible purely gravitational curvature-squared terms in six dimensions: Riemann, Ricci, and scalar curvature squared. A linear combination of these invariants describes the off-shell completion of the Gauss-Bonnet term, recently presented in arXiv:1706.09330. We study properties of the Einstein-Gauss-Bonnet super-gravity, which plays a central role in the effective low-energy description of α′-corrected string theory compactified to six dimensions, including a detailed analysis of the spectrum about the AdS3 × S3 solution. We also present a novel locally superconformal invariant based on a higher-derivative action for the linear multiplet. This invariant, which includes gravitational curvature-squared terms, can be defined both coupled to the standard-Weyl or dilaton-Weyl multiplet for conformal supergravity. In the first case, we show how the addition of this invariant to the supersymmetric Einstein-Hilbert term leads to a dynamically generated cosmological constant and non-supersymmetric (A)dS6 solutions. In the dilaton-Weyl multiplet, the new off-shell invariant includes Ricci and scalar curvaturesquared terms and possesses a nontrivial dependence on the dilaton field.
Recursive representations of arbitrary Virasoro conformal blocks
Authors: Cho Minjae , Collier Scott , Yin Xi
Published: April 2019

Abstract

We derive recursive representations in the internal weights of N -point Virasoro conformal blocks in the sphere linear channel and the torus necklace channel, and recursive representations in the central charge of arbitrary Virasoro conformal blocks on the sphere, the torus, and higher genus Riemann surfaces in the plumbing frame.
The conservation status assessment of Natura 2000 forest habitats in Europe: capabilities, potentials and challenges of national forest inventories data
Authors: Alberdi Iciar , Nunes Leónia , Kovac Marko , Bonheme Ingrid , Cañellas Isabel , Rego Francisco Castro , Dias Susana , Duarte Inês , Notarangelo Monica , Rizzo Maria , Gasparini Patrizia
Published: April 2019

Key message

There is a need to improve the consistency of international information concerning the conservation status assessment of the species and habitat types in the Natura 2000 reports. National Forest Inventories could contribute towards a more objective and harmonised assessment although their use shows some challenges as low precision for rare or small area habitats. Recommendations for a set of 12 structural and functional indicators are provided.

Context

There are differences among Member States as regards applying conservation status assessment and priorities according to the Directive on the conservation of natural habitats (Habitats Directive).

Aims

This paper aims to analyse the consistency as regards forest habitat types reporting and the use and suitability of National Forest Inventories (NFIs) to assess their conservation status, as well as to provide recommendations for harmonised assessments through NFIs.

Methods

A survey was carried out concerning the use of NFI data to report within the commitments of the Habitat Directive. The survey covered 13 European countries, accounting for 62% of forest habitat area. Additionally, case studies were carried out in four countries.

Results

The identification of forest habitat types and the set of quantitative and/or qualitative indicators differ between countries. The use of NFI data is being considered in seven countries and it is expected to increase for the 2013–2018 reporting period. The main challenges reported of use of NFI data are related to the habitat identification and their mapping, and the monitoring frequency, design and costs (i.e. rare or small area habitats).

Conclusion

It is necessary to improve the comparability of the conservation status assessments between countries.
Compressible fluids and active potentials
Authors: Constantin Peter , Drivas Theodore D. , Nguyen Huy Q. , Pasqualotto Federico
Published: April 2019

We consider a class of one dimensional compressible systems with degenerate diffusion coefficients. We establish the fact that the solutions remain smooth as long as the diffusion coefficients do not vanish, and give local and global existence results. The models include the barotropic compressible Navier-Stokes equations, shallow water systems and the lubrication approximation of slender jets. In all these models the momentum equation is forced by the gradient of a solution-dependent potential: the active potential. The method of proof uses the Bresch-Desjardins entropy and the analysis of the evolution of the active potential.
The Museum as Rift Zone – The Construction and Representation of “East” and “Central” Africa in the (Belgian) Congo Museum/Royal Museum for Central Africa
Authors: Couttenier Maarten
Published: April 2019

This article discusses how the (post)colonial museum in Tervuren helped to create an artificial separation between “East” and “Central” Africa on both sides of Lake Tanganyika, while in reality this was and still is a zone of encounter. The exclusion of the “Arab” was twofold. First, East African objects were not exhibited. Second, “Eastern” material culture that was collected in Central Africa, became represented as imported traces of “barbary,” only highlighting the “civilizing mission” of European colonization.
The Metropolitan Effect: Colonial Influence on the Internationalization of Francophone African Firms
Authors: Meouloud Tah Ahmed , Mudambi Ram , Hill TL
Published: April 2019

Drawing on the experience of firms of various sizes from Francophone Africa, we explore how the internationalization trajectories of frontier economy firms may vary from those predicted by theory. The firms studied followed social, linguistic, cultural, and institutional gradients to internationalize first to France, rather than to neighboring countries, and did so in search of not only markets and resources but also legitimacy. In turn, the sales, resources, and legitimacy acquired in France supported further international expansion, sometimes even to neighboring countries. Although our insights derive from the experience of Francophone firms from Africa, we argue that for firms from all former colonies, the internationalization trajectory leads through the colonial center. Our findings underline the roles of legitimacy-seeking and network ties in the internationalization of frontier market firms and serve as a salutatory reminder of the lingering influence of colonial ties on international business.
STRUCTURE AND PERSUASION IN SUETONIUS’DE VITA CAESARVM
Authors: Garrett Phoebe
Published: April 2019

At the sentence level Suetonius often appears to be neutral, but I argue here that the persuasive force in the arrangement of his material creates a portrait that is absolutely not neutral. As David Wardle put it in a 2016 review, ‘Anyone who reads Suetonius without regard to the careful structures within which the biographer places his material can produce almost any picture.’ Yet these ‘careful structures’ are a mystery known only to the initiated. This paper lays out the complex and varied ways in which Suetonius uses structure, specifically the ‘rubric system’ of arranging his material under subheadings and those subheadings in sequences, in the hope that with this knowledge we see more accurately what ‘picture’ the biographer creates.
THE POETICS OF LATER GREEK ECPHRASIS: CHRISTODORUS COPTUS, THEPALATINE ANTHOLOGYAND THEPERIOCHAEOF NONNUS’DIONYSIACA
Authors: Middleton Fran
Published: April 2019

There is increasing interest in what might be thought ‘special’ about late antique poetry. Two volumes of recent years have focused on Latin poetry of this time,Classics Renewed: Reception and Innovation in the Latin Poetry of Late Antiquityedited by Scott McGill and Joseph Pucci (2016) as well asThe Poetics of Late Latin Literatureedited by Jaś Elsner and Jesús Hernández Lobato (2017), while it has become increasingly acceptable to remark on late antiquity as a cultural period in its own right, rather than a point of transition between high antiquity and the middle ages. Greek poetry of late antiquity has yet to receive the level of attention offered to Latin literature of this time, and so it is to help answer the question of what may be thought special about late antique Greek poetry that I here discuss the poetics of later Greek ecphrasis.
BMI and adiposity based approach to obesity: the need for ethnic specificity. A reply to Kapooret al. (2019)
Authors: Kryst Łukasz , Żegleń Magdalena , Wronka Iwona , Woronkowicz Agnieszka , Bilińska-Pawlak Inez , Das Rituparna , Saha Rana , Das Sukanta , Dasgupta Parasmani
Published: April 2019

The ethnicity of the studied group is one of the key characteristics that should be taken into consideration when analysing the problem of overweight and obesity. It is especially crucial in populations of countries such as India, where the proportion of the fat to lean mass and general adiposity are significantly different from those observed among Europeans. This can cause a higher risk of various metabolic-related diseases to appear at relatively lower absolute adiposity. Therefore, there is a need for further research regarding the issues of body mass and composition in Indian populations, to obtain additional information as well as to develop ethnically specific cut-off points.
Clinical and theoretical relevance of responses to analogues of psychotic experiences in people with psychotic experiences with and without a need-for-care: an experimental study
Authors: Ward Thomas , Garety Philippa. A , Jackson Mike , Peters Emmanuelle
Published: April 2019

Background

Certain ways of responding to psychotic experiences (PEs) appear more commonly associated with clinical distress (e.g. avoidance) and other ways with benign or positive outcomes (e.g. reappraisal and acceptance). Past research has largely been limited to retrospective self-report. We aimed to compare clinical and non-clinical individuals on experimental analogues of anomalous experiences.

Method

Response styles of two groups with persistent PEs (clinical n = 84; non-clinical n = 92) and a control group without PEs (n = 83) were compared following experimental analogues of thought interference (Cards Task, Telepath) and hearing voices (Virtual Acoustic Space Paradigm).

Results

The non-clinical group with PEs were less likely to endorse unhelpful response styles, such as passive responding or attempts to avoid, suppress, worry about or control mental experiences, compared with the clinical group on all three tasks. The clinical group were more likely to endorse unhelpful response styles compared with controls on two out of three tasks (Cards Task and Telepath). The non-clinical group performed similarly to controls on unhelpful responding across all tasks. There were no group differences for helpful response styles, such as cognitive reappraisal or mindful acceptance of experiences.

Conclusions

In line with cognitive models of psychosis, the findings suggest that the way in which individuals respond to unusual experiences may be an important factor in understanding clinical distress, supporting the therapeutic rationale of targeting potentially unhelpful patterns of response.
Video for Knowledge Translation: Engaging Older Adults in Social and Physical Activity
Authors: Ottoni Callista A. , Sims-Gould Joanie , McKay Heather A.
Published: April 2019

Une vaste majorité des Canadiens âgés ne pratiquent pas suffisamment d’activité physique. Le développement de stratégies originales et innovantes encourageant et appuyant les modes de vie actifs est donc urgent. La vidéo est un outil prometteur pour l’application de connaissances (AC) visant l’engagement de divers publics dans la discussion et l’adoption de comportements favorisant la santé. L’Approche systématique pour les vidéos fondées sur des données probantes (Systematic Approach to Evidence-informed Video, SAEV), qui fournit un cadre pour guider et structurer le développement de vidéos ayant pour objectif l’AC, a été utilisée pour la création et la diffusion d’un documentaire de 19 minutes,I’d Rather Stay(https://vimeo.com/80503957). Quarante-huit participants âgés de 60 ans et plus ont visionné la vidéo, participé à des groupes de discussion et rempli des questionnaires concernant cette vidéo. Les données ont été recueillies après le visionnement et lors d’un suivi organisé six mois plus tard. La vidéo a éduqué, encouragé et mobilisé les personnes âgées sur les questions liées à l’autonomie, à l’activité physique et aux liens sociaux. Nous encourageons les chercheurs à adopter des stratégies d’AC auxquelles les personnes âgées peuvent s’identifier, qui sont accessibles et par lesquelles elles peuvent s’engager à un niveau critique, autant sur le plan émotionnel qu’intellectuel, comme les vidéos basées sur des preuves scientifiques.
Effects of a mobile game-based English vocabulary learning app on learners’ perceptions and learning performance: A case study of Taiwanese EFL learners
Authors: Chen Chih-Ming , Liu Huimei , Huang Hong-Bin
Published: April 2019

Many studies have demonstrated that vocabulary size plays a key role in learning English as a foreign language (EFL). In recent years, mobile game-based learning (MGBL) has been considered a promising scheme for successful acquisition and retention of knowledge. Thus, this study applies a mixed methodology that combines quantitative and qualitative approaches to assess the effects of PHONE Words, a novel mobile English vocabulary learning app (application) designed with game-related functions (MEVLA-GF) and without game-related functions (MEVLA-NGF), on learners’ perceptions and learning performance. During a four-week experiment, 20 sophomore students were randomly assigned to the experimental group with MEVLA-GF support or the control group with MEVLA-NGF support for English vocabulary learning. Analytical results show that performance in vocabulary acquisition and retention by the experimental group was significantly higher than that of the control group. Moreover, questionnaire results confirm that MEVLA-GF is more effective and satisfying for English vocabulary learning than MEVLA-NGF. Spearman rank correlation results show that involvement and dependence on gamified functions were positively correlated with vocabulary learning performance.
Measuring lunchtime consumption in school cafeterias: a validation study of the use of digital photography
Authors: Marcano-Olivier Mariel , Erjavec Mihela , Horne Pauline J , Viktor Simon , Pearson Ruth
Published: April 2019

Objective

The present study tested the validity of a digital image-capture measure of food consumption suitable for use in busy school cafeterias.

Design

Lunches were photographed pre- and post-consumption, and food items were weighed pre- and post-consumption for comparison.

Setting

A small research team recorded children’s lunchtime consumption in one primary and one secondary school over seven working days.

Participants

A primary-school sample of 121 children from North Wales and a secondary-school sample of 124 children from the West Midlands, UK, were utilised. Nineteen children were excluded because of incomplete data, leaving a final sample of 239 participants.

Results

Results indicated that (i) consumption estimates based on images were accurate, yielding only small differences between the weight- and image-based judgements (median bias=0·15–1·64 g, equating to 0·45–3·42 % of consumed weight) and (ii) good levels of inter-rater agreement were achieved, ranging from moderate to near perfect (Cohen’sκ=0·535–0·819). This confirmed that consumption estimates derived from digital images were accurate and could be used in lieu of objective weighed measures.

Conclusions

Our protocol minimised disruption to daily lunchtime routine, kept the attrition low, and enabled better agreement between measures and raters than was the case in the existing literature. Accurate measurements are a necessary tool for all those engaged in nutrition research, intervention evaluation, prevention and public health work. We conclude that our simple and practical method of assessment could be used with children across a range of settings, ages and lunch types.
The Top‐Down Solidification of Iron Asteroids Driving Dynamo Evolution
Authors: Neufeld Jerome A. , Bryson James F. J. , Nimmo Francis
Published: April 2019

The cores of some small planetesimals, such as asteroid (16) Psyche, are thought to have been exposed through collisions during the early solar system that removed their mantles. These small bodies likely solidified from the top down representing a fundamentally different solidification regime to that of Earth's core. Here we derive simplified models of the downward solidification of the metallic crust and consider thermal convection and the potential for viscous delamination of the weak, warm base of the crust to provide a buoyancy flux sufficient to drive a dynamo. Thermal buoyancy is very short lived (∼1,000 years) and therefore cannot be the source of measured paleomagnetic remanence. In contrast, viscous delamination is found to provide a long‐lasting buoyancy flux sufficient to generate an intense, multipolar magnetic field, while not greatly affecting the crustal solidification time. Our results suggest that a Psyche‐sized (150‐km radius) body solidified in roughly 6.7–20 Myr and that delamination produced a strong magnetic field over much of this time. Finally, including light, insoluble impurities, such as sulfur, results in a partially solid mushy zone at the base of the crust. This further weakens the base of the crust and results in smaller‐scale delamination events. Despite a significant change in the dynamics of delamination, the time to total solidification and the predicted properties of the magnetic field are broadly comparable to the sulfur‐free case, though we argue this may result in observable compositional stratification of the body.
Fan‐Surface Evidence for Debris‐Flow Avulsion Controls and Probabilities, Saline Valley, California
Authors: de Haas T. , Densmore A. L. , den Hond T. , Cox N. J.
Published: April 2019

Debris‐flow fans form by shifts of the active channel, termed avulsions. Field and experimental evidence suggest that debris‐flow avulsions may be induced by depositional lobes that locally plug a channel or superelevation of the channel bed above the surrounding fan surface, by analogy to fluvial fans. To understand debris‐flow avulsion processes, we differentiate between these controls by quantifying the spatial distribution of debris‐flow lobe and channel dimensions, along with channel‐bed superelevation, on nine debris‐flow fans in Saline Valley, California, USA. Channel beds are generally superelevated by 2–5 channel depths above the fan surface, and locally by more than 7 channel depths, thereby substantially exceeding superelevation on fluvial fans. Depositional‐lobe thickness and channel depth decrease with distance from the fan apex, although both are highly variable across the fans. Median channel depths roughly correspond to the 50th–75th percentiles of lobe thicknesses, while minimum channel depths roughly correspond to the 10th–25th percentiles. In contrast, the thicknesses of lobes that have triggered avulsions roughly equal local channel depths and are on average twice as thick as the local median lobe thickness. The spatial correspondence between avulsion locations and thick lobe deposits, and the lack of correlation with channel‐bed superelevation, leads us to infer that avulsions on these fans are mostly caused by thick lobes forming channel plugs. Although results may vary with climatic and tectonic setting, our findings indicate that avulsion hazard assessment on populated fans should include mapping and monitoring of channel depths relative to typical deposit thicknesses on a given fan.
Classification of the human phox homology (PX) domains based on their phosphoinositide binding specificities
Authors: Chandra Mintu , Chin Yanni K.-Y. , Mas Caroline , Feathers J. Ryan , Paul Blessy , Datta Sanchari , Chen Kai-En , Jia Xinying , Yang Zhe , Norwood Suzanne J. , Mohanty Biswaranjan , Bugarcic Andrea , Teasdale Rohan D. , Henne W. Mike , Mobli Mehdi , Collins Brett M.
Published: April 2019

Phox homology (PX) domains are membrane interacting domains that bind to phosphatidylinositol phospholipids or phosphoinositides, markers of organelle identity in the endocytic system. Although many PX domains bind the canonical endosome-enriched lipid PtdIns3P, others interact with alternative phosphoinositides, and a precise understanding of how these specificities arise has remained elusive. Here we systematically screen all human PX domains for their phospholipid preferences using liposome binding assays, biolayer interferometry and isothermal titration calorimetry. These analyses define four distinct classes of human PX domains that either bind specifically to PtdIns3P, non-specifically to various di- and tri-phosphorylated phosphoinositides, bind both PtdIns3P and other phosphoinositides, or associate with none of the lipids tested. A comprehensive evaluation of PX domain structures reveals two distinct binding sites that explain these specificities, providing a basis for defining and predicting the functional membrane interactions of the entire PX domain protein family.
Mad1 destabilizes p53 by preventing PML from sequestering MDM2
Authors: Wan Jun , Block Samuel , Scribano Christina M. , Thiry Rebecca , Esbona Karla , Audhya Anjon , Weaver Beth A.
Published: April 2019

Mitotic arrest deficient 1 (Mad1) plays a well-characterized role in the mitotic checkpoint. However, interphase roles of Mad1 that do not impact mitotic checkpoint function remain largely uncharacterized. Here we show that upregulation of Mad1, which is common in human breast cancer, prevents stress-induced stabilization of the tumor suppressor p53 in multiple cell types. Upregulated Mad1 localizes to ProMyelocytic Leukemia (PML) nuclear bodies in breast cancer and cultured cells. The C-terminus of Mad1 directly interacts with PML, and this interaction is enhanced by sumoylation. PML stabilizes p53 by sequestering MDM2, an E3 ubiquitin ligase that targets p53 for degradation, to the nucleolus. Upregulated Mad1 displaces MDM2 from PML, freeing it to ubiquitinate p53. Upregulation of Mad1 accelerates growth of orthotopic mammary tumors, which show decreased levels of p53 and its downstream effector p21. These results demonstrate an unexpected interphase role for Mad1 in tumor promotion via p53 destabilization.
A TetR-family transcription factor regulates fatty acid metabolism in the archaeal model organism Sulfolobus acidocaldarius
Authors: Wang Kun , Sybers David , Maklad Hassan Ramadan , Lemmens Liesbeth , Lewyllie Charlotte , Zhou Xiaoxiao , Schult Frank , Bräsen Christopher , Siebers Bettina , Valegård Karin , Lindås Ann-Christin , Peeters Eveline
Published: April 2019

Fatty acid metabolism and its regulation are known to play important roles in bacteria and eukaryotes. By contrast, although certain archaea appear to metabolize fatty acids, the regulation of the underlying pathways in these organisms remains unclear. Here, we show that a TetR-family transcriptional regulator (FadRSa) is involved in regulation of fatty acid metabolism in the crenarchaeon Sulfolobus acidocaldarius. Functional and structural analyses show that FadRSa binds to DNA at semi-palindromic recognition sites in two distinct stoichiometric binding modes depending on the operator sequence. Genome-wide transcriptomic and chromatin immunoprecipitation analyses demonstrate that the protein binds to only four genomic sites, acting as a repressor of a 30-kb gene cluster comprising 23 open reading frames encoding lipases and β-oxidation enzymes. Fatty acyl-CoA molecules cause dissociation of FadRSa binding by inducing conformational changes in the protein. Our results indicate that, despite its similarity in overall structure to bacterial TetR-family FadR regulators, FadRSa displays a different acyl-CoA binding mode and a distinct regulatory mechanism.
Single-molecule characterization of extrinsic transcription termination by Sen1 helicase
Authors: Wang S. , Han Z. , Libri D. , Porrua O. , Strick T. R.
Published: April 2019

Extrinsic transcription termination typically involves remodeling of RNA polymerase by an accessory helicase. In yeast this is accomplished by the Sen1 helicase homologous to human senataxin (SETX). To gain insight into these processes we develop a DNA scaffold construct compatible with magnetic-trapping assays and from which S. cerevisiae RNA polymerase II (Pol II), as well as E. coli RNA polymerase (ecRNAP), can efficiently initiate transcription without transcription factors, elongate, and undergo extrinsic termination. By stalling Pol II TECs on the construct we can monitor Sen1-induced termination in real-time, revealing the formation of an intermediate in which the Pol II transcription bubble appears half-rewound. This intermediate requires ~40 sec to form and lasts ~20 sec prior to final dissociation of the stalled Pol II. The experiments enabled by the scaffold construct permit detailed statistical and kinetic analysis of Pol II interactions with a range of cofactors in a multi-round, high-throughput fashion.
High carbon emissions from thermokarst lakes of Western Siberia
Authors: Serikova S. , Pokrovsky O. S. , Laudon H. , Krickov I. V. , Lim A. G. , Manasypov R. M. , Karlsson J.
Published: April 2019

The Western Siberia Lowland (WSL), the world’s largest permafrost peatland, is of importance for understanding the high-latitude carbon (C) cycle and its response to climate change. Warming temperatures increase permafrost thaw and production of greenhouse gases. Also, permafrost thaw leads to the formation of lakes which are hotspots for atmospheric C emissions. Although lakes occupy ~6% of WSL, lake C emissions from WSL remain poorly quantified. Here we show high C emissions from lakes across all permafrost zones of WSL. The C emissions were especially high in shoulder seasons and in colder permafrost-rich regions. The total C emission from permafrost-affected lakes of WSL equals ~12 ± 2.6 Tg C yr−1 and is 2-times greater than region’s C export to the Arctic coast. The results show that C emission from WSL lakes is a significant component in the high-latitude C cycle, but also suggest that C emission may decrease with warming.
Identification of the kinase STK25 as an upstream activator of LATS signaling
Authors: Lim Sanghee , Hermance Nicole , Mudianto Tenny , Mustaly Hatim M. , Mauricio Ian Paolo Morelos , Vittoria Marc A. , Quinton Ryan J. , Howell Brian W. , Cornils Hauke , Manning Amity L. , Ganem Neil J.
Published: April 2019

The Hippo pathway maintains tissue homeostasis by negatively regulating the oncogenic transcriptional co-activators YAP and TAZ. Though functional inactivation of the Hippo pathway is common in tumors, mutations in core pathway components are rare. Thus, understanding how tumor cells inactivate Hippo signaling remains a key unresolved question. Here, we identify the kinase STK25 as an activator of Hippo signaling. We demonstrate that loss of STK25 promotes YAP/TAZ activation and enhanced cellular proliferation, even under normally growth-suppressive conditions both in vitro and in vivo. Notably, STK25 activates LATS by promoting LATS activation loop phosphorylation independent of a preceding phosphorylation event at the hydrophobic motif, which represents a form of Hippo activation distinct from other kinase activators of LATS. STK25 is significantly focally deleted across a wide spectrum of human cancers, suggesting STK25 loss may represent a common mechanism by which tumor cells functionally impair the Hippo tumor suppressor pathway.
Novel insights into gene expression regulation during meiosis revealed by translation elongation dynamics
Authors: Sabi Renana , Tuller Tamir
Published: April 2019

The ability to dynamically control mRNA translation has a great impact on many intracellular processes. Whereas it is believed that translational control in eukaryotes occurs mainly at initiation, the condition-specific changes at the elongation level and their potential regulatory role remain unclear. Using computational approaches applied to ribosome profiling data, we show that elongation rate is dynamic and can change considerably during the yeast meiosis to facilitate the selective translation of stage-specific transcripts. We observed unique elongation changes during meiosis II, including a global inhibition of translation elongation at the onset of anaphase II accompanied by a sharp shift toward increased elongation for genes required at this meiotic stage. We also show that ribosomal proteins counteract the global decreased elongation by maintaining high initiation rates. Our findings provide new insights into gene expression regulation during meiosis and demonstrate that codon usage evolved, among others, to optimize timely translation.
Domestic cats (Felis catus) discriminate their names from other words
Authors: Saito Atsuko , Shinozuka Kazutaka , Ito Yuki , Hasegawa Toshikazu
Published: April 2019

Two of the most common nonhuman animals that interact with humans are domestic dogs (Canis familiaris) and cats (Felis catus). In contrast to dogs, the ability of domestic cats to communicate with humans has not been explored thoroughly. We used a habituation-dishabituation method to investigate whether domestic cats could discriminate human utterances, which consisted of cats’ own names, general nouns, and other cohabiting cats’ names. Cats from ordinary households and from a ‘cat café’ participated in the experiments. Among cats from ordinary households, cats habituated to the serial presentation of four different general nouns or four names of cohabiting cats showed a significant rebound in response to the subsequent presentation of their own names; these cats discriminated their own names from general nouns even when unfamiliar persons uttered them. These results indicate that cats are able to discriminate their own names from other words. There was no difference in discrimination of their own names from general nouns between cats from the cat café and household cats, but café cats did not discriminate their own names from other cohabiting cats’ names. We conclude that cats can discriminate the content of human utterances based on phonemic differences.
Publisher Correction: Quantitative Evaluation of the Mechanical Risks Caused by Focal Cartilage Defects in the Knee
Authors: Venäläinen Mikko S. , Mononen Mika E. , Salo Jari , Räsänen Lasse P. , Jurvelin Jukka S. , Töyräs Juha , Virén Tuomas , Korhonen Rami K.
Published: April 2019

A correction has been published and is appended to both the HTML and PDF versions of this paper. The error has not been fixed in the paper.
The asymmetry of plasma membranes and their cholesterol content influence the uptake of cisplatin
Authors: Rivel Timothée , Ramseyer Christophe , Yesylevskyy Semen
Published: April 2019

The composition of the plasma membrane of malignant cells is thought to influence the cellular uptake of cisplatin and to take part in developing resistance to this widespread anti-cancer drug. In this work we study the permeation of cisplatin through the model membranes of normal and cancer cells using molecular dynamics simulations. A special attention is paid to lipid asymmetry and cholesterol content of the membranes. The loss of lipid asymmetry, which is common for cancer cells, leads to a decrease in their permeability to cisplatin by one order of magnitude in comparison to the membranes of normal cells. The change in the cholesterol molar ratio from 0% to 33% also decreases the permeability of the membrane by approximately one order of magnitude. The permeability of pure DOPC membrane is 5–6 orders of magnitude higher than one of the membranes with realistic lipid composition, which makes it as an inadequate model for the studies of drug permeability.
Area-dependent change of response in the rat’s inferior colliculus to intracochlear electrical stimulation following neonatal cochlear damage
Authors: Hatano Miyako , Kelly Jack B. , Zhang Huiming
Published: April 2019

To understand brain changes caused by auditory sensory deprivation, we recorded local-field potentials in the inferior colliculus of young adult rats with neonatal cochlear damage produced by systemic injections of amikacin. The responses were elicited by electrical stimulation of the entire cochlea and recorded at various locations along a dorsolateral-ventromedial axis of the inferior colliculus. We found that hair cells were completely destroyed and spiral ganglion neurons were severely damaged in the basal cochleae of amikacin-treated animals. Hair cells as well as spiral ganglion neurons were damaged also in the middle and apical areas of the cochlea, with the damage being greater in the middle than the apical area. Amplitudes of local-field potentials were reduced in the ventromedial inferior colliculus, but enhanced in the dorsolateral inferior colliculus. Latencies of responses were increased over the entire structure. The enhancement of responses in the dorsolateral inferior colliculus was in contrast with the damage of hair cells and spiral ganglion cells in the apical part of the cochlea. This contrast along with the overall increase of latencies suggests that early cochlear damage can alter neural mechanisms within the inferior colliculus and/or the inputs to this midbrain structure.
Encapsulation of Lactobacillus fermentum K73 by Refractance Window drying
Authors: Aragón-Rojas Stephania , Quintanilla-Carvajal María Ximena , Hernández-Sánchez Humberto , Hernández-Álvarez Alan Javier , Moreno Fabian Leonardo
Published: April 2019

The purpose of this work was to model the survival of the microorganism and the kinetics of drying during the encapsulation ofLactobacillus fermentumK73 by Refractance Window drying. A whey culture medium with and without addition of maltodextrin were used as encapsulation matrices. The microorganism with the encapsulation matrices was dried at three water temperatures (333, 343 and 353 K) until reaching balanced moisture. Microorganism survival and thin layer drying kinetics were studied by using mathematical models. Results showed that modified Gompertz model and Midilli model described the survival of the microorganism and the drying kinetics, respectively. The most favorable process conditions found with the mathematical modelling were a drying time of 2460 s, at a temperature of 353 K. At these conditions, a product with 9.1 Log CFU/g and a final humidity of 10% [wet basis] using the culture medium as encapsulation matrix was obtained. The result shows that Refractance Window can be applied to encapsulate the microorganism probiotic with a proper survival of the microorganism.
Inhibition of the thioredoxin system by PX-12 (1-methylpropyl 2-imidazolyl disulfide) impedes HIV-1 infection in TZM-bl cells
Authors: Lundberg Mathias , Mattsson Åse , Reiser Kathrin , Holmgren Arne , Curbo Sophie
Published: April 2019

Human immunodeficiency virus (HIV-1) entry is initiated by the binding between the viral envelope glycoprotein gp120 and the host receptor CD4, and followed by reduction of structural disulfides of gp120 and CD4. The host thioredoxin-1 (Trx1) efficiently reduces disulfides of gp120 and CD4 in vitro, and recently CD4-dependent HIV-1 entry was shown to be inhibited by anti-Trx1-antibodies, indicating a central role for Trx1. 1-methylpropyl-2-imidazolyl disulfide (PX-12) is a reversible inhibitor of the Trx1 system that may also cause a slow irreversible thioalkylation of Trx1. It was developed as an antitumor agent, however, the current study aimed to determine if it also has an anti-HIV-1 effect. We show that PX-12 has anti-HIV-1(IIIB) activity in TZM-bl cells, in fact, no virus was detected inside the cells in the presence of 10 µM PX-12. Moreover, PX-12 inhibited the enzymatic activity of Trx1 and the Trx1-dependent disulfide reduction of gp120. Microtubule polymerization and formation of acetylated microtubules were also inhibited, activities shown to be required for HIV-1 life cycle propagation. In conclusion, our data strengthens the notion that the early steps of the HIV-1 life cycle depends on the Trx1 system and indicate that the Trx1 system may be a rational drug target for HIV-1 treatment.
Ocean acidification causes mortality in the medusa stage of the cubozoan Carybdea xaymacana
Authors: Chuard Pierre J. C. , Johnson Maggie D. , Guichard Frédéric
Published: April 2019

Ocean pH is decreasing due to anthropogenic activities, and the consequences of this acidification on marine fauna and ecosystems are the subject of an increasing number of studies. Yet, the impact of ocean acidification (OA) on several abundant and ecologically important taxa, such as medusozoans, is poorly documented. To date there have been no studies on the effect of post-2050 OA projections on the medusa stage of jellyfish. As medusae represent the reproductive stage of cnidarians, negative impacts on adult jellyfish could severely impact the long-term survival of this group. Using a laboratory experiment, we investigated the effect of 2300 OA projections (i.e. pH of 7.5) on the mortality rate of the medusa-stage of the cubozoan species Carybdea xaymacana, compared to ambient seawater pH conditions (i.e. pH of 8.1). After a 12-h exposure to OA, C. xaymacana medusae suffered higher mortality rates compared to ambient conditions. This study represents the first evidence of the potential lethal effects of post-2050 OA projections on jellyfish. The higher metabolic rates of cubozoans compared to other cnidarians might make box jellyfish more vulnerable to OA. A decrease in the density of cnidarians could lead to harmful ecological events, such as algal blooms.
Supervised machine learning of ultracold atoms with speckle disorder
Authors: Pilati S. , Pieri P.
Published: April 2019

We analyze how accurately supervised machine learning techniques can predict the lowest energy levels of one-dimensional noninteracting ultracold atoms subject to the correlated disorder due to an optical speckle field. Deep neural networks with different numbers of hidden layers and neurons per layer are trained on large sets of instances of the speckle field, whose energy levels have been preventively determined via a high-order finite difference technique. The Fourier components of the speckle field are used as the feature vector to represent the speckle-field instances. A comprehensive analysis of the details that determine the possible success of supervised machine learning tasks, namely the depth and the width of the neural network, the size of the training set, and the magnitude of the regularization parameter, is presented. It is found that ground state energies of previously unseen instances can be predicted with an essentially negligible error given a computationally feasible number of training instances. First and second excited state energies can be predicted too, albeit with slightly lower accuracy and using more layers of hidden neurons. We also find that a three-layer neural network is remarkably resilient to Gaussian noise added to the training-set data (up to 10% noise level), suggesting that cold-atom quantum simulators could be used to train artificial neural networks.
Lp-PLA2 activity and mass and CRP are associated with incident symptomatic peripheral arterial disease
Authors: Fatemi Shahab , Gottsäter Anders , Zarrouk Moncef , Engström Gunnar , Melander Olle , Persson Margaretha , Acosta Stefan
Published: April 2019

Long follow up is needed in prospective cohort study evaluation of plasma biomarkers for incident peripheral arterial disease (PAD) Middle-aged PAD-free individuals from the cardiovascular cohort of the Malmö Diet and Cancer study (n = 5550; 1991–94) were followed prospectively for a median time of 23.4 years. The plasma biomarkers lipoprotein-associated phospholipase A2 (Lp-PLA2) activity and mass, proneurotensin, and CRP, were studied in relation to incidence of PAD until December 31st, 2016. The diagnosis of PAD could be validated and confirmed in 98%. Cox regression was used to calculate hazard ratios (HR) per 1 standard deviation increment of each respective log transformed plasma biomarker. Cumulative incidence of PAD was 4.4% (men 5.9%, women 3.3%). Adjusting for age, gender, smoking, body mass index, hypertension, diabetes mellitus, Lp-PLA2 activity (HR 1.33; 95% CI 1.17–1.52), Lp-PLA2 mass (HR 1.20; 95% CI 1.05–1.37) and CRP (HR 1.55; 95% CI 1.36–1.76) remained independently associated with incident PAD. The plasma biomarkers Lp-PLA2 activity and mass, and CRP were markers of PAD risk, implying that they might be useful biomarkers for subclinical atherosclerosis and atherosclerotic disease.