bluuebunny/crossref_metadata_2025_split huggingface dataset:
A simple system for moist convection: the Rainy–Bénard model
Authors: Vallis Geoffrey K. , Parker Douglas J. , Tobias Steven M. 
Published: January 2019

Rayleigh–Bénard convection is one of the most well-studied models in fluid mechanics. Atmospheric convection, one of the most important components of the climate system, is by comparison complicated and poorly understood. A key attribute of atmospheric convection is the buoyancy source provided by the condensation of water vapour, but the presence of radiation, compressibility, liquid water and ice further complicate the system and our understanding of it. In this paper we present an idealized model of moist convection by taking the Boussinesq limit of the ideal-gas equations and adding a condensate that obeys a simplified Clausius–Clapeyron relation. The system allows moist convection to be explored at a fundamental level and reduces to the classical Rayleigh–Bénard model if the latent heat of condensation is taken to be zero. The model has an exact, Rayleigh-number-independent ‘drizzle’ solution in which the diffusion of water vapour from a saturated lower surface is balanced by condensation, with the temperature field (and so the saturation value of the moisture) determined self-consistently by the heat released in the condensation. This state is the moist analogue of the conductive solution in the classical problem. We numerically determine the linear stability properties of this solution as a function of Rayleigh number and a non-dimensional latent-heat parameter. We also present some two-dimensional, time-dependent, nonlinear solutions at various values of Rayleigh number and the non-dimensional condensational parameters. At sufficiently low Rayleigh number the system converges to the drizzle solution, and we find no evidence that two-dimensional self-sustained convection can occur when that solution is stable. The flow transitions from steady to turbulent as the Rayleigh number or the effects of condensation are increased, with plumes triggered by gravity waves emanating from other plumes. The interior dries as the level of turbulence increases, because the plumes entrain more dry air and because the saturated boundary layer at the top becomes thinner. The flow develops a broad relative humidity minimum in the domain interior, only weakly dependent on Rayleigh number when that is high.
Altered global brain network topology as a trait marker in patients with anorexia nervosa
Authors: Geisler Daniel , Borchardt Viola , Boehm Ilka , King Joseph A. , Tam Friederike I. , Marxen Michael , Biemann Ronald , Roessner Veit , Walter Martin , Ehrlich Stefan 
Published: January 2019

AbstractBackgroundResting state functional magnetic resonance imaging studies have identified functional connectivity patterns associated with acute undernutrition in anorexia nervosa (AN), but few have investigated recovered patients. Thus, a trait connectivity profile characteristic of the disorder remains elusive. Using state-of-the-art graph–theoretic methods in acute AN, the authors previously found abnormal global brain network architecture, possibly driven by local network alterations. To disentangle trait from starvation effects, the present study examines network organization in recovered patients.MethodsGraph–theoretic metrics were used to assess resting-state network properties in a large sample of female patients recovered from AN (recAN, n = 55) compared with pairwise age-matched healthy controls (HC, n = 55).ResultsIndicative of an altered global network structure, recAN showed increased assortativity and reduced global clustering as well as small-worldness compared with HC, while no group differences at an intermediate or local network level were evident. However, using support-vector classifier on local metrics, recAN and HC could be separated with an accuracy of 70.4%.ConclusionsThis pattern of results suggests that long-term recovered patients have an aberrant global brain network configuration, similar to acutely underweight patients. While the finding of increased assortativity may represent a trait marker of AN, the remaining findings could be seen as a scar following prolonged undernutrition.
Exploring the cultural flexibility of the ACT model as an effective therapeutic group intervention for Turkish speaking communities in East London
Authors: Perry Aradhana , Gardener Chelsea , Oliver Joseph E. , Taş Çiğdem , Özenç Cansu 
Published: January 2019

AbstractThis study describes a successful community-based partnership project between statutory and third-sector services in East London; The City and Hackney Black and Minority Ethnic (BME) Access Service [East London NHS Foundation Trust (ELFT)] collaborated with Derman, a local community organization supporting the well-being of Turkish-speaking communities, to explore the cultural adaptability of an empirically supported, third-wave cognitive behavioural intervention, Acceptance and Commitment Therapy (ACT). The aim was to develop a culturally acceptable group that was responsive to the therapeutic needs of participants from Turkish-speaking communities. The study implemented a mixed-method analysis with a one group pre/post-test design to examine the effectiveness of a 7-session culturally adapted ACT group intervention and a descriptive approach was implemented to assess usefulness, relevance and acceptability. Results demonstrated an overall positive effect of the culturally adapted ACT intervention in terms of both symptoms and patient-reported outcomes. Participants showed significant improvements on measures of depression (p= 0.014), anxiety (p= 0.041) and psychological distress (p= 0.003). The magnitude of these changes was categorized as large, with effect sizes from 0.90 to 2.03. Qualitative responses indicated that the group was experienced as enjoyable and useful and was considered to be an accessible and acceptable therapeutic format. Although a pilot within clinical practice, the findings provide preliminary support for the clinical utility of ACT as an effective, culturally acceptable therapeutic approach for Turkish-speaking communities living in an urban UK setting. The study highlights the importance of culturally appropriate service development and a need for further research within this area.
Representation of Synoptic‐Scale Rossby Wave Packets and Blocking in the S2S Prediction Project Database
Authors: Quinting J. F. , Vitart F. 
Published: January 2019

AbstractRossby wave packets (RWPs) are one of the dominating midlatitude atmospheric phenomena. A realistic representation of RWPs is essential for a skillful prediction of the day‐to‐day weather and its extremes. Using an objective RWP tracking technique, this study verifies the representation of RWPs for all models in the Subseasonal to Seasonal (S2S) Prediction Project Database. Consistent with reanalyses, the reforecasts show one RWP every 4 days. The three models with the coarsest grid spacing tend to overestimate the propagation distance due to a negative RWP decay frequency bias over the Atlantic‐European sector. A verification of atmospheric blocking suggests that this bias is related to a negative blocking frequency bias in the same region. The biases are reduced in models with finer grid spacing. However, that this bias reduction is not only dependent on the grid spacing highlights the effect of the different representation of key physical processes on RWPs and blocking.
Cassini Radio Occultation Observations of Titan's Ionosphere: The Complete Set of Electron Density Profiles
Authors: Dalba Paul A. , Withers Paul 
Published: January 2019

AbstractTitan's ionosphere is an important component of the moon's environment. Ionospheric densities above ≈900 km have been studied with in situ measurements, but few density profiles for lower altitudes has been reported. Here we report the generation of the complete set of twenty ionospheric electron density profiles from the Cassini Radio Science Subsystem instrument, including seven profiles not previously reported (inbound and outbound profiles for flybys T101, T102, and T117 and outbound profile for flyby T119). Uncertainties on average electron density profiles are generally 100–250 cm−3. On the whole, the main features of the new profiles are generally consistent with previous studies. Specifically, a single layer of plasma with peak density of 1,000–3,000 cm−3, peak altitude of 1,000–1,300 km, and full‐width at half maximum of a few hundred kilometers. Two new profiles are “disturbed” similar to three identified by previous studies. Based on inspection of the underlying individual profiles, which generally come from two ground stations on opposite sides of Earth, disturbed terrestrial ionospheric conditions are not responsible for the disturbed nature of these Titan ionospheric profiles. A significant plasma layer is present at 500–700 km in several profiles. This low‐altitude plasma layer can occur in profiles that are not disturbed.
Quantifying Emissions of CO and NOx Using Observations From MOPITT, OMI, TES, and OSIRIS
Authors: Zhang X. , Jones D. B. A. , Keller M. , Walker T. W. , Jiang Z. , Henze D. K. , Worden H. M. , Bourassa A. E. , Degenstein D. A. , Rochon Y. J. 
Published: January 2019

AbstractWe use the GEOS‐Chem four‐dimensional variational data assimilation system to estimate emissions of carbon monoxide (CO) and nitrogen oxides (NOx) in November 2009 and July 2010. We assimilated CO retrievals from The Measurements of Pollution In The Troposphere (MOPITT), ozone (O3) retrievals from the Tropospheric Emission Spectrometer (TES) and the Optical Spectrograph and InfraRed Imager System (OSIRIS), and NO2 columns from the Ozone Monitoring Instrument (OMI). By assimilating data for multiple chemical species with the four‐dimensional variational scheme we obtain a consistent chemical state over the assimilation period. The modeled O3 bias was reduced to less than 3.5 ppbv everywhere, relative to independent aircraft O3 data, except in the high‐latitude upper troposphere and lower stratosphere. We found that in November, the CO and NOx emission estimates obtained with the multiple species assimilation were generally comparable to those inferred from assimilating only MOPITT or OMI data, respectively, whereas in July the differences were larger. For the main anthropogenic source regions, the inferred North American and European emissions responded most strongly to the multispecies information in the assimilation. In July, North American and European CO emission estimates differed by 31% and 65% relative to the MOPITT‐only estimates, respectively. We also found large differences for the North American and European NOx emission estimates, which differed by 27% and 16% relative to the OMI‐only estimates, respectively. Our results highlight the potential benefit of exploiting the additional constraints offered by multispecies chemical data assimilation.
Benchmarking NAPL Redirection and Matrix Entry at Fracture Intersections Below the Water Table
Authors: Walton Kenneth M. , Unger Andre J. A. , Ioannidis Marios A. , Parker Beth L. 
Published: January 2019

AbstractThis paper examines a numerical modeling approach for two‐phase flow and considers the contribution of a simple network of fracture intersections to the whole discrete fracture‐matrix flow system; it develops a benchmark problem for a non‐wetting, dense, non‐aqueous phase liquid invading a water‐saturated, discretely fractured, porous medium near a fracture intersection under cases of invader fluid redirection at the intersection, breakthrough to a constricted fracture branch, or breakthrough into the rock matrix using capillary entry pressures. Numerical simulation is performed with a multiphase, compositional DFM software, using a finite difference discretization of the governing equations. In these simulation cases, the “star‐delta” method for eliminating line‐ and point‐control volumes at fracture intersections is contrasted to retaining all control volumes, the goal being to test the efficacy of the star‐delta simplification. Flux over the domain's boundaries and mass storage are comparison metrics. Results indicate that conduits (or lack thereof) have a strong effect on NAPL architecture with an accompanying change in efflux in the case of redirection; they have some early‐time effects on architecture and efflux in constricted fracture cases. The scenario presented herein leads to multiphase flow forecasts in intersection conduits which can serve as an experimentally testable hypothesis and as a benchmark for comparisons of simulator forecasts.
High-performance Raman quantum memory with optimal control in room temperature atoms
Authors: Guo Jinxian , Feng Xiaotian , Yang Peiyu , Yu Zhifei , Chen L. Q. , Yuan Chun-Hua , Zhang Weiping 
Published: January 2019

AbstractQuantum memories are essential for quantum information processing. Techniques have been developed for quantum memory based on atomic ensembles. The atomic memories through optical resonance usually suffer from the narrow-band limitation. The far off-resonant Raman process is a promising candidate for atomic memories due to broad bandwidths and high speeds. However, to date, the low memory efficiency remains an unsolved bottleneck. Here, we demonstrate a high-performance atomic Raman memory in 87Rb vapour with the development of an optimal control technique. A memory efficiency of above 82.0% for 6 ns~20 ns optical pulses is achieved. In particular, an unconditional fidelity of up to 98.0%, significantly exceeding the no-cloning limit, is obtained with the tomography reconstruction for a single-photon level coherent input. Our work marks an important advance of atomic memory towards practical applications in quantum information processing.
Solution structure of TbTFIIS2-2 PWWP domain from Trypanosoma brucei and its binding to H4K17me3 and H3K32me3
Authors: Wang Rui , Gao Jie , Zhang Jiahai , Zhang Xuecheng , Xu Chao , Liao Shanhui , Tu Xiaoming 
Published: January 2019

Abstract
Posttranslational modiﬁcations (PTMs) of core histones, such as histone methylation, play critical roles in a variety of biological processes including transcription regulation, chromatin condensation and DNA repair. In T. brucei, no domain recognizing methylated histone has been identified so far. TbTFIIS2-2, as a potential transcription elongation factors in T. brucei, contains a PWWP domain in the N-terminus which shares low sequence similarity compared with other PWWP domains and is absent from other TFIIS factors. In the present study, the solution structure of TbTFIIS2-2 PWWP domain was determined by NMR spectroscopy. TbTFIIS2-2 PWWP domain adopts a global fold containing a ﬁve-strand β-barrel and two C-terminal α-helices similar to other PWWP domains. Moreover, through systematic screening, we revealed that TbTFIIS2-2 PWWP domain is able to bind H4K17me3 and H3K32me3. Meanwhile, we identified the critical residues responsible for the binding ability of TbTFIIS2-2 PWWP domain. The conserved cage formed by the aromatic amino acids in TbTFIIS2-2 PWWP domain is essential for its binding to methylated histones.
The molecular basis of transient heme-protein interactions: analysis, concept and implementation
Authors: Wißbrock Amelie , Paul George Ajay Abisheck , Brewitz Hans Henning , Kühl Toni , Imhof Diana 
Published: January 2019

AbstractDeviant levels of available heme and related molecules can result from pathological situations such as impaired heme biosynthesis or increased hemolysis as a consequence of vascular trauma or bacterial infections. Heme-related biological processes are affected by these situations, and it is essential to fully understand the underlying mechanisms. While heme has long been known as an important prosthetic group of various proteins, its function as a regulatory and signaling molecule is poorly understood. Diseases such as porphyria are caused by impaired heme metabolism, and heme itself might be used as a drug in order to downregulate its own biosynthesis. In addition, heme-driven side effects and symptoms emerging from heme-related pathological conditions are not fully comprehended and thus impede adequate medical treatment. Several heme-regulated proteins have been identified in the past decades, however, the molecular basis of transient heme-protein interactions remains to be explored. Herein, we summarize the results of an in-depth analysis of heme binding to proteins, which revealed specific binding modes and affinities depending on the amino acid sequence. Evaluating the binding behavior of a plethora of heme-peptide complexes resulted in the implementation of a prediction tool (SeqD-HBM) for heme-binding motifs, which eventually led and will perspectively lead to the identification and verification of so far unknown heme-regulated proteins. This systematic approach resulted in a broader picture of the alternative functions of heme as a regulator of proteins. However, knowledge on heme regulation of proteins is still a bottomless barrel that leaves much scope for future research and development.
Low‐loss reverse blocking IGBT with PNM structure and trench collectors
Authors: Liu Fenghao , Huang Mingmin , Li Rui , Lai Li , Gong Min 
Published: January 2019

A reverse blocking insulated gate bipolar transistor (IGBT) with partially narrow mesa (PNM) structure and trench collectors is proposed. An n‐type carrier stored (n‐cs) layer is introduced between two trench gates with the bulgy bottom, forming the PNM structure, which nicely shields high electric field from the n‐cs layer at the forward blocking state. Hence, a highly doped n‐cs layer can be used to enhance the carrier storage effect in the n‐drift region at on‐state to reduce the on‐state voltage [VCE(sat)]. Besides, an n‐buffer layer is introduced between two trench collectors at the back side, acting as a field‐stop (FS) layer at forwarding blocking state. At the reverse blocking state, the trench collectors shield high electric field from the n‐buffer region and the n‐cs layer acts as an FS layer, which ensures a high reverse breakdown voltage. Numerical simulation results show that the 1.4 kV proposed reverse blocking‐IGBT can use a 38% thinner n‐drift region and obtain a 45% lower VCE(sat) than the conventional counterpart.
New interleaved fully soft switched pulse width modulation boost converter with one auxiliary switch
Authors: Rezvanyvardom Mahdi , Mirzaei Amin , Rahimi Saba 
Published: January 2019

This study proposes a new interleaved pulse width modulation boost converter that uses only one auxiliary switch in its structure to create soft‐switching condition for all semiconductor elements. This way leads that the proposed converter has a simpler structure in comparison with other similar interleaved topologies. Moreover, the auxiliary circuit is not located in the main power path from input to the output. So, the current rate of the elements in the auxiliary circuit is very low. Due to soft‐switching condition for all semiconductor elements, the proposed topology has low power losses and high efficiency. The efficiency of the converter is 97.6% at full load range. Besides, using the interleaved structure in the proposed converter leads to lower current stresses on the circuit elements. A 120 W prototype of the proposed converter is implemented. The experimental results confirm the aforementioned advantages of the proposed converter such as high efficiency in comparison with other similar topologies.
Link between trees of fragmenting granules and deep downflows in MHD simulation
Authors: Roudier T. , Malherbe J. M. , Stein R. F. , Frank Z. 
Published: January 2019

Context. Trees of fragmenting granules (TFG) and associated flows are suspected to play a major role in the formation of the network in the quiet Sun. We investigate the counterparts, in terms of dynamics, of surface structures detectable by high resolution observations in deeper layers up to 15 Mm, which are only available from numerical simulations.
Aims. The first aim is to demonstrate that TFG can be evidenced either from surface intensitites, vertical (Vz), or Doppler (Vdop) velocities. The second is to show that horizontal flows, which are derived from intensities or Vz/Vdop flows, are in good agreement, and that this is the case for observations and numerical simulations. The third objective is to apply this new Vz-based method to a 3D simulation to probe relationships between horizontal surface flows, TFG, and deep vertical motions.
Methods. The TFG were detected after oscillation filtering of intensities or Vz/Vdop flows, using a segmentation and labelling technique. Surface horizontal flows were derived from local correlation tracking (LCT) and from intensities or Vz/Vdop flows. These methods were applied to Hinode observations, 2D surface results of a first simulation, and 3D Vz data of a second simulation.
Results. We find that TFG and horizontal surface flows (provided by the LCT) can be detected either from intensities or Vz/Vdop component, for high resolution observations and numerical simulations. We apply this method to a 3D run providing the Vz component in depth. This reveals a close relationship between surface TFG (5 Mm mesoscale) and vertical downflows 5 Mm below the surface. We suggest that the dynamics of TFG form larger scales (the 15–20 Mm supergranulation) associated with 15 Mm downflowing cells below the surface.
Conclusions. The TFG and associated surface flows seem to be essential to understanding the formation and evolution of the network at the meso and supergranular scale.
Dégradation d’un anticancéreux dans les eaux usées
Authors:   Équipe iGEM GO Paris-Saclay 2018, Briand William , Dao Ousmane , Garnier Guillaume , Guegan Raphaël , Marta Britany , Maupu Clémence , Miesch Julie , Papadopoulo Kenn , Radoux Arthur , Rojahn Julie , Zhu Yueying , Aubry Céline , Bouloc Phillipe , Bury-Moné Stéphanie , Ferré Arnaud , Lautru Sylvie , Namy Olivier , Sabeti-Azad Mahnaz 
Published: January 2019

iGEM (pour international genetically engineered machine) est un concours international autour de la biologie synthétique réunissant des étudiants de toutes disciplines (mathématiques, physique, biologie, arts, etc.). « L’objectif est de construire un système biologique fonctionnel complexe, en assemblant des composants individuels moléculaires simples et standardisés (fragments d’ADN), appelés « briques biologiques » (biobriques), sorte de « legos » moléculaires, entreposés au MIT (Massachusetts Institute of Technology) (le registry of standard biological parts contient environ 20 000 biobriques). C’est une démarche proche de celle de l’ingénieur qui assemble des circuits électroniques ». En 2004, lors de sa création par le MIT (→), la compétition iGEM regroupait une quarantaine de projets ; 14 ans plus tard, elle accueille 350 équipes (6 000 étudiants, avec leurs instructeurs) issues des universités du monde entier. Elle culmine en un Giant Jamboree de quatre jours à Boston en novembre, au cours duquel les équipes présentent leur projet. Le « wiki » de la compétition (www.igem.org) présente l’ensemble des projets ainsi que le palmarès. Cette année, ont été décernées 114 médailles d’or, 68 d’argent et 107 de bronze. Neuf équipes françaises étaient engagées.
(→) Voir l’article de J. Peccoud et L. Coulombel, dont certains passages sont repris dans ce « chapo », m/s n° 5, mai 2007, page 551