bluuebunny/crossref_metadata_2025 huggingface dataset:
Engineering Ultrathin MoS2 Nanosheets Anchored on N‐Doped Carbon Microspheres with Pseudocapacitive Properties for High‐Performance Lithium‐Ion Capacitors
Authors: Jiang Jiangmin , Zhang Yadi , An Yufeng , Wu Langyuan , Zhu Qi , Dou Hui , Zhang Xiaogang
Published: April 2019

Lithium‐ion capacitors (LICs) are emerging as one of the most advanced energy storage devices by combining the virtues of both supercapacitor and lithium‐ion battery. The key point of constructing high‐performance LICs is to balance the electrochemical kinetics and capacity mismatch between battery‐type anode and capacitive‐type cathode materials. Herein, a strategy is presented for simultaneous manipulation of a MoS2/N‐doped carbon microspheres anode and hierarchical porous carbon cathode by using polyimide precursor. Owing to the fast lithium diffusion rate, high pseudocapacitive behavior, and expanding the interlayer of the MoS2 composite network architecture, the material can achieve excellent rate capacity and cyclic stability. Hierarchical porous carbon has an ultrahigh specific surface area and superior capacitive behavior. A high‐performance LIC is successfully constructed by using the superior anode and cathode materials. The device can deliver a maximum energy density of 120 Wh kg−1 and keep the capacity retention of 85.5% after 4000 cycles, revealing the competition in advanced energy storage devices. Accordingly, the simultaneous manipulation of metal sulfide and hierarchical porous carbon by the same precursor can be used toward fabricating other ideal electrode structures for energy storage.
Monitoring the riverine pulse: Applying high‐frequency nitrate data to advance integrative understanding of biogeochemical and hydrological processes
Authors: Burns Douglas A. , Pellerin Brian A. , Miller Matthew P. , Capel Paul D. , Tesoriero Anthony J. , Duncan Jonathan M.
Published: April 2019

Widespread deployment of sensors that measure river nitrate (NO3−) concentrations has led to many recent publications in water resources journals including review papers focused on data quality assurance, improved load calculations, and better nutrient management. The principal objective of this study is to review and synthesize studies of high‐frequency NO3− data that have aimed to improve understanding of the hydrologic and biogeochemical processes underlying episodic, diel, and long‐term stream NO3− dynamics. Investigations have provided unprecedented detail on hysteresis and flushing patterns during high flow, seasonal variation during baseflow, and responses to multiyear climate variation. Analyses of high‐frequency data have led to notable advances in understanding how climate variation affects spatial and temporal NO3− patterns, especially dry–wet cycles and antecedent moisture. Further advances have been limited by few investigations that include high‐frequency measurements outside the channel and the short duration of many records. High‐frequency data for multiple constituents have provided new insight to the relative roles of hydrology and biogeochemistry as highlighted by studies of the roles of autotrophic uptake, denitrification, riparian evapotranspiration, and temperature‐driven changes in viscosity as drivers of diel patterns. Comparisons of short duration high‐frequency data with long duration low‐frequency data have described similarities and differences in concentration–discharge patterns and highlighted the role of legacy stores. Investigators have applied innovative analysis approaches not previously possible with low‐frequency or temporally irregular data. Future availability of long duration high‐frequency data will provide new insight to processes, resulting in improved conceptual models and a deeper understanding of the role of climate variation.

This article is categorized under:

Science of Water > Water Quality

Science of Water > Methods

Water and Life > Nature of Freshwater Ecosystems
Enhanced adsorption and slow release of phosphate by dolomite–alginate composite beads as potential fertilizer
Authors: Huang Yu‐Xi , Liu Meng‐Jie , Chen Shi , Jasmi Irfan Iskandar , Tang Yuanzhi , Lin Shihong
Published: April 2019

The recovery and reuse of phosphorus (P) from wastewater treatment process is a critical and viable target for sustainable P utilization. This study explores a novel approach of integrating ultrafine mineral particles into hydrogel matrixes for enhancing the capacity of phosphate adsorption. Dolomite‐alginate (DA) hydrogel beads were prepared by integrating ball‐milled, ultrafine dolomite powders into calcium cross‐linked alginate hydrogel matrix. The adsorption isotherms followed a Langmuir–Freundlich adsorption model with higher specific adsorption capacity than those reported in literature. The kinetics of phosphate adsorption suggest that the adsorption is diffusion controlled. Investigation of adsorption capacity at different pH showed a maximum adsorption capacity in the pH range of 7–10. Lastly, we demonstrated that the DA beads are capable of slowly releasing most of the adsorbed phosphate, which is an important criterion for them to be an effective phosphorous fertilizer. This study, using DA composite hydrogel as an example, demonstrates a promising strategy of immobilizing ultrafine mineral adsorbents into biocompatible hydrogel matrix for effective recovery of phosphorous resource from wastewater.

Practitioner points

Integration of dolomite and alginate hydrogel beads is demonstrated using ball milling.

Ball milling process increases the specific adsorption capacity of dolomite on phosphorus.

Adsorption isotherms, kinetics, and pH effects of the dolomite–alginate beads are investigated.

The dolomite–alginate beads can be used as slow‐release phosphorus fertilizer.
Does It Really Matter? Assessing the Performance Effects of Changes in Leadership and Management Structures in Nordic Higher Education
Authors: Pulkkinen Kirsi , Aarrevaara Timo , Berg Laila Nordstrand , Geschwind Lars , Hansen Hanne Foss , Hernes Helge , Kivistö Jussi , Lind Jonas Krog , Lyytinen Anu , Pekkola Elias , Pinheiro Rómulo , Stensaker Bjørn , Söderlind Johan
Published: April 2019

Universities are public organisations, which operate in a highly institutionalised environment. They are heavily dependent on public resources. As such, universities are susceptible to shifts in governance arrangements but are also far from being passive recipients of reform agendas. They face demands from multiple internal constituencies (academics, administrators, students, managers) and from a variety of external stakeholders. This chapter explores the interplay between governance arrangements resulting from policy shifts and university dynamics. It sets the stage for the book, asking the following research questions: (1) what characterises changes in governance regimes in Nordic universities in the last decade and a half, and (2) what effects have these changes had in the evolution of higher education systems? The chapter takes a comparative approach and identifies similarities and differences across the Nordic countries. This chapter serves as a frame of reference for the book and includes a common methods and data section.
Performance in Higher Education Institutions and Its Variations in Nordic Policy
Authors: Kivistö Jussi , Pekkola Elias , Berg Laila Nordstrand , Hansen Hanne Foss , Geschwind Lars , Lyytinen Anu
Published: April 2019

The need for greater efficiency, productivity and quality in the higher education sector has triggered increased governmental interest towards different mechanisms of accountability, especially evaluation and performance measurement. This interest has developed over a relatively long period of time, but it has now reached its culmination point in many ways. For instance, advances in citation tracking, performance data collection and databases and the professionalisation of evaluative practices and methods have opened new avenues for verifying accountability. This chapter offers definitions for the key concepts used throughout the book, as follows: accountability, evaluation, and performance measurement and management. Each section is followed by a short contextualisation of the concept in Denmark, Finland, Norway and Sweden. The chapter ends with a short discussion about the policy convergence between Nordic countries and the reasons for it.
The MacMahon R-matrix
Authors: Awata Hidetoshi , Kanno Hiroaki , Mironov Andrei , Morozov Alexei , Suetake Kazuma , Zenkevich Yegor
Published: April 2019

Abstract

We introduce an R-matrix acting on the tensor product of MacMahon representations of Ding-Iohara-Miki (DIM) algebra

$$ {U}_{q,t}\left({\widehat{\widehat{\mathfrak{gl}}}}_1\right) $$

U

q
,
t

g
l

^

^

1

. This R-matrix acts on pairs of 3d Young diagrams and retains the nice symmetry of the DIM algebra under the permutation of three deformation parameters q, t
−1 and

$$ \frac{t}{q} $$

t
q

. We construct the intertwining operator for a tensor product of the horizontal Fock representation and the vertical MacMahon representation and show that the intertwiners are permuted using the MacMahon R-matrix.
p-adic Mellin amplitudes
Authors: Jepsen Christian Baadsgaard , Parikh Sarthak
Published: April 2019

Abstract

In this paper, we propose a p-adic analog of Mellin amplitudes for scalar operators, and present the computation of the general contact amplitude as well as arbitrary-point tree-level amplitudes for bulk diagrams involving up to three internal lines, and along the way obtain the p-adic version of the split representation formula. These amplitudes share noteworthy similarities with the usual (real) Mellin amplitudes for scalars, but are also significantly simpler, admitting closed-form expressions where none are available over the reals. The dramatic simplicity can be attributed to the absence of descendant fields in the p-adic formulation.
The worldsheet dual of the symmetric product CFT
Authors: Eberhardt Lorenz , Gaberdiel Matthias R. , Gopakumar Rajesh
Published: April 2019

Abstract

Superstring theory on

$$ {\mathrm{AdS}}_3 \times {S}^3\times {\mathbb{T}}^4 $$

AdS
3

×

S
3

×

T
4

with the smallest amount of NS-NS flux (“k = 1”) is shown to be dual to the spacetime CFT given by the large N limit of the free symmetric product orbifold Sym
N

$$ \left({\mathbb{T}}^4\right) $$

T
4

. To define the worldsheet theory at k = 1, we employ the hybrid formalism in which the AdS3 × S3 part is described by the

$$ \mathfrak{p}\mathfrak{s}\mathfrak{u}{\left(1,1\Big|2\right)}_1 $$

p
s
u

1
,
1
|
2

1

WZW model (which is well defined). Unlike the case for k ≥ 2, it turns out that the string spectrum at k = 1 does not exhibit the long string continuum, and perfectly matches with the large N limit of the symmetric product. We also demonstrate that the fusion rules of the symmetric orbifold are reproduced from the worldsheet perspective. Our proposal therefore affords a tractable worldsheet description of a tensionless limit in string theory, for which the dual CFT is also explicitly known.
Biomechanical and Functional Improvements Gained by Proximal Tibia Osteotomy Correction of Genu Varum in Patients with Knee Pain
Authors: Da Cunha Rachael J. , Kraszewski Andrew P. , Hillstrom Howard J. , Fragomen Austin T. , Rozbruch S. Robert
Published: April 2019

Background

Mechanical axis malalignment contributes to abnormal forces across the knee joint. Genu varum, or increased medial mechanical axis deviation (MAD), increases force transmission and contact pressures to the medial compartment. With increasing MAD and femoral-tibial mechanical axis angle (MAA), contact forces within the medial or lateral compartment of the knee significantly increase with increasing deformity. This may lead to knee pain, further deformity, and medial compartment degenerative joint disease, which can interfere with participation in sports and diminish quality of life.

Purposes/Questions

We sought to evaluate patients with knee pain with bilateral genu varum and determine the effect of bilateral proximal tibial osteotomies on knee biomechanics, deformity correction, and functional outcomes.

Methods

This was a single-center, prospective study of eight limbs in four patients. Consecutive patients presenting with knee pain and bilateral genu varum originating from the proximal tibia were included. All patients underwent staged bilateral proximal tibial osteotomies with gradual deformity correction with an external fixator. Subjects underwent a three-dimensional (3D) instrumented motion analysis during level walking. A 3D lower extremity model was built and bilateral knee frontal plane kinematics and kinetics during the stance phase of gait were determined. Radiographic analysis was performed including assessment of MAD, MAA, and medial proximal tibial angle (MPTA). Functional outcomes were assessed with the Knee Injury and Osteoarthritis Outcome Score (KOOS), the 36-item Short-Form Survey (SF-36), the Lower Limb Questionnaire (LLQ), and a visual analog scale (VAS) for pain.

Results

The average time in the external fixator for a single limb was 97 days. The average follow-up period was 310 days. All biomechanical outcomes significantly improved, including knee adduction angle (7.8° to 1.8°), knee adduction moments (first peak, − 0.450 to − 0.281 nm/kg, and second peak, − 0.381 to − 0.244 nm/kg), and knee adduction moment impulse (− 0.233 to − 0.150 nm s/kg). There was a significant improvement in MAA, MAD, and MPTA. All patients showed qualitative improvement in mean scores on VAS (11.8 to 0.0), LLQ (77 to 93), KOOS (64 to 84), and SF-36 (71 to 88).

Conclusion

These findings suggest that bilateral proximal tibial osteotomy may be effective in improving knee biomechanics during gait and correcting mechanical alignment in patients with bilateral genu varum. Patients also demonstrated improvement in functional outcome scores. This technique should thus be considered in patients with varus knee osteoarthritis in the setting of genu varum to alleviate symptoms and potentially decrease further clinical deterioration.
Life threatening hyperkalemia treated with prolonged continuous insulin infusion
Authors: Thani Saif Awlad , Farsi Muzna Al , Omrani Sara Al
Published: April 2019

Hyperkalemia is a life threatening electrolyte imbalance that may be fatal if not treated appropriately. There are multiple medications used to treat hyperkalemia to lower it to a safe level. We report a case of a 4-month old infant with Pseudohypoaldosteronism who had cardiac arrest secondary to severe hyperkalemia of 12.3mmol/l. It was refractory to anti hyperkalemic medications that necessitated the transfer of the patient to a tertiary hospital for dialysis. The potassium level has dropped gradually to a normal level with continuous insulin infusion and dextrose for almost 12 hours that waved the need of the dialysis. This case highlights the effectiveness of prolonged continuous insulin infusion in treating life-threatening hyperkalemia especially in hospitals where there are no dialysis services available or until the dialysis is initiated.
Effectiveness of Hall current and exponential heat source on unsteady heat transport of dusty TiO2-EO nanoliquid with nonlinear radiative heat
Authors: Mahanthesh Basavarajappa , Shashikumar Nagavangala Shankarappa , Gireesha Bijjanal Jayanna , Animasaun Isac Lare
Published: April 2019

The problem of exponential heat source across a flowing nanofluid (TiO2-EO; titanium oxide-Engine oil) containing tiny dust particles on a deformable planar plate has been an open question in meteorology. In this paper, the boundary layer transient two-phase flow of dusty nanoliquid on an isothermal plate which is deforming with time-dependent velocity in the presence of exponential heat source is studied. The impacts of Hall current, nonlinear radiative heat and an irregular heat source (temperature based heat source and exponential space-based heat source) are also accounted. Dusty nanofluid is the composition of dust particles and nanoliquid (TiO2-EO). Using relevant transformations, the system of PDEs is rehabilitated to the system of ODEs and then treated numerically. Exploration of the impacts of pertinent parameters on velocity and temperature fields is performed via graphical illustrations. Numeric data for skin friction factor and the Nusselt number is presented and their characteristics are analyzed/quantified through the slope of linear regression via data points.

Highlights Boundary layer flow of dusty nanoliquid past a isothermal plate is studied. Impacts of Hall current and irregular heat source are also accounted. Role of physical parameters are focused in momentum and heat transport distributions. Numeric data for skin friction factor and the Nusselt number is presented.
Direct numerical simulation of high-speed transition due to roughness elements
Authors: Shrestha Prakash , Candler Graham V.
Published: April 2019

We study and compare instability mechanisms of a Mach 5.65 laminar boundary layer tripped by an isolated diamond-shaped trip and by an array of diamond-shaped trips using direct numerical simulations. A low-Reynolds-number experiment, consisting of the trip array (Semper & Bowersox, AIAA J., vol. 55 (3), 2017, pp. 808–817), is used to validate our simulations. Three dynamically prominent flow structures are observed in both trip configurations. These flow structures are the upstream vortex system, the shock system, and the downstream shear layers/counter-rotating streamwise vortices that originate from the top and sides of the trips. Analysis of the power spectral density of pressure reveals the source of instability to be an interaction between the shear layers and the counter-rotating streamwise vortices downstream of both trip configurations. The interaction leads to the formation of hairpin-like structures that eventually break down to turbulent flow. This finding contrasts with that of an isolated cylindrical trip (Subbareddy et al., J. Fluid Mech., vol. 748, 2014, pp. 848–878) where the upstream vortex system is found to be the source of instability. Therefore, the shape of a trip plays an important role in the instability mechanism. Furthermore, dynamic mode decomposition (Rowley et al., J. Fluid Mech., vol. 641, 2009, pp. 115–127; Schmid, J. Fluid Mech., vol. 656, 2010, pp. 5–28) of three-dimensional snapshots of pressure fluctuations unveil globally dominant modes consistent with the power spectral density analysis in both diamond-shaped trip configurations.
First report of Eocene gadiform fishes from the Trans-Urals (Sverdlovsk and Tyumen regions, Russia)
Authors: Marramà Giuseppe , Carnevale Giorgio , Smirnov Pavel V. , Trubin Yaroslav S. , Kriwet Jürgen
Published: April 2019

The recent 2014–2017 controlled excavations carried out in quarries of Sverdlovsk and Tyumen regions, Ural and Western Siberia, are contributing to the knowledge of the middle to late Eocene marine fauna from the Turgay Strait, mainly composed of invertebrates and cartilaginous and bony fishes. Here we present a preliminary report of the bony fishes collected during the campaigns carried out in two Eocene Trans-Urals localities. The sediments of these localities were deposited in a large epicontinental marine basin during the middle to late Eocene, when the Turgay Strait connected the Arctic waters to the North and the Peritethys to the South. Most of the bony fish material examined can be assigned to codfishes (Gadiformes) according to morphological comparison with living and fossil taxa. In particular, nearly complete three-dimensionally preserved lower jaws are confidently assigned to the Merlucciidae, whereas isolated vertebrae and bones are referred to as Gadiformes incertae sedis. This report documents the easternmost occurrence of this group of fishes in the northern hemisphere during the early phases of their radiation, revealing their presence into the Turgay Strait before its closure.
The range of linguistic units: Distance effects in English mandative subjunctive constructions
Authors: BERG THOMAS , ZINGLER TIM , LOHMANN ARNE
Published: April 2019

This study examines the role of distance in the decision among grammatical variants. The empirical test case is the English mandative subjunctive construction, which co-occurs with an embedded modal auxiliary, a subjunctive or an indicative verb form. The fact that the subjunctive is triggered by specific lexical items allows one to measure the distance between the triggering unit and the target verb. This distance is found to play a significant role in the grammatical decision process. With increasing distance between trigger and target, the probability of selecting a modal auxiliary increases and the probability of selecting the subjunctive decreases. The theoretical account hinges on the range and strength of linguistic units. Syntactic units (i.e. modals) are claimed to have a wider range than morphological units (i.e. indicative and subjunctive). Furthermore, the indicative is claimed to have a wider range than the subjunctive. Varying ranges are interpreted as varying decay rates. The lower decay rate of syntactic as compared to morphological units results from the syntactic level being superordinated to the morphological level in language production. The inclusion of the semantic and the phonological levels confirms that the position of a level in the structural hierarchy determines its range.
IndexCub: a ready-to-use set of routines for X-ray diffraction line profile analysis
Authors: Contreras-Torres F. F.
Published: April 2019

The growing interest in the use of powder X-ray diffractometry for materials’ characterization has led to the introduction of relevant concepts (e.g. microstructure, strain, anisotropy, texture) to undergraduate teaching in engineering and science. In this concern, the study of polycrystalline materials underlays the use of appropriate software: free, licensed, proprietary, or commercial to assist research on structure determination, structure refinement, and microstructure characterization. Today with the easy access to personal computers, routines for powder diffractometry also becomes feasible to use for non-specialist. Therefore, it would be relevant that students with computing knowledge may decide to improve routines on such three tasks incorporating their own computational approaches. In this study, we show the development of a ready-to-use and open source program written in GNU-Octave (v4.2.1) focused on X-ray diffraction line-profile analysis. The programing language platform was chosen mainly because of two reasons: (1) there is no requirement for commercial licenses, meaning that both programing language and routines can be downloaded online, facilitating collaborative efforts between students, instructors, and developers, and (2) easy re-coding of evaluation strategies is always allowed through fast implementation of modules into the code. The code, IndexCub, features routines for background subtraction, whole profile smoothing, and Kα2 radiation removal, location of diffraction peaks positions, indexing for cubic specimens, multi peak separation of individual peaks, and evaluation of full-width at half-maximum and integral breadth values. Microstructure properties are characterized through the use of integral breadth methods (e.g. Williamson–Hall) and Fourier analysis (e.g. Warren–Averbach), and the anisotropy effects are incorporated introducing calculations of contrast factors. In terms of diffraction domain sizes, size distribution, and the lattice microstrain, the analysis of the microstructure is discussed along with examples for polycrystalline coarse-grained materials (NaCl), epitaxial film (Si), and thin-films (Au) specimens. The code facilitates the understanding of microstructure analysis by using theoretical approaches well established and in state-steady level.
Increased QT and P-wave dispersion during attack-free period in pediatric patients with migraine attacks
Authors: Tosun Oyku , Karatoprak Elif
Published: April 2019

Introduction:

Migraine is a common neurovascular disease characterised with recurrent attacks by pain-free periods. It has been suggested that both sympathetic and parasympathetic dysfunctions play a role in its pathophysiology.

Aim:

The aim of our study was to investigate the ECG changes during attack-free period in children with migraine, in terms of QTc interval, QTc, and P-wave dispersion to evaluate the autonomic nervous system disturbance.

Methods:

Sixty children who were diagnosed with migraine were included as patient group and 50 healthy, age- and body mass index-matched children who were examined for innocent murmur were included as control group. The patients’ routine ECG records were screened from the outpatient clinic files. The durations of P-wave, QT, and QTc intervals and dispersion values and heart rates (beats/minute) were compared between the patient and control groups.

Results:

P maximum and P dispersion were significantly higher, and P minimum was significantly lower in the migraine group compared with the control group. QT–QTc maximum and QT–QTc dispersion were significantly higher and QT–QTc minimum was significantly lower in the migraine group compared with the control group.

Conclusion:

According to our findings, although migraine patients were asymptomatic and no arrhythmia was detected in the surface ECG, sympathovagal balance in the sympathetic system, which may be disrupted in favour of the sympathetic system, should continue even in the attack-free period, and we should be careful in terms of serious arrhythmias that may develop in these patients.
A pilot study of acceptance-based behavioural weight loss for adolescents with obesity
Authors: Tronieri Jena Shaw , Wadden Thomas A. , Leonard Sharon M. , Berkowitz Robert I.
Published: April 2019

Background:

Acceptance and commitment therapy (ACT) is a psychological treatment that has been found to increase weight loss in adults when combined with lifestyle modification, compared with the latter treatment alone. However, an ACT-based treatment for weight loss has never been tested in adolescents.

Methods:

The present pilot study assessed the feasibility and acceptability of a 16-week, group ACT-based lifestyle modification treatment for adolescents and their parents/guardians. The co-primary outcomes were: (1) mean acceptability scores from up to 8 biweekly ratings; and (2) the percentage reduction in body mass index (BMI) from baseline to week 16. The effect size for changes in cardiometabolic and psychosocial outcomes from baseline to week 16 also was examined.

Results:

Seven families enrolled and six completed treatment (14.3% attrition). The mean acceptability score was 8.8 for adolescents and 9.0 for parents (on a 1–10 scale), indicating high acceptability. The six adolescents who completed treatment experienced a 1.3% reduction in BMI (SD = 2.3, d = 0.54). They reported a medium increase in cognitive restraint, a small reduction in hunger, and a small increase in physical activity. They experienced small improvements in most quality of life domains and a large reduction in depression.

Conclusions:

These preliminary findings indicate that ACT plus lifestyle modification was a highly acceptable treatment that improved weight, cognitive restraint, hunger, physical activity, and psychosocial outcomes in adolescents with obesity.
Observing Synchrony in Dyads
Authors: Marques-Quinteiro Pedro , Mata André , Simão Cláudia , Gaspar Rui , Farias Ana Rita
Published: April 2019

Abstract. This research tested whether observing members of a dyad behave in synchrony influences observers’ expectations and intentions about that dyad. In four studies, participants observed a dyad move in synchrony and were asked to make inferences about them. Results suggest that interpersonal synchrony serves as a social cue, such that observers expect the members of the dyad to work well together. Moreover, synchrony makes observers more likely to want to affiliate with the dyad. These findings shed light on how the social function of synchrony extends beyond the people who experience it to those who observe it.
Projected Changes in United States Regional Extreme Heat Days Derived From Bivariate Quantile Mapping of CMIP5 Simulations
Authors: Schoof J. T. , Pryor S. C. , Ford T. W.
Published: April 2019

Projections of multivariate climate extremes require methodological approaches that can maintain relationships among variables. Here we apply a piecewise multivariate quantile mapping approach to temperature and humidity projections from a subset of models from the Fifth Coupled Model Intercomparison Project and analyze the resulting climatology of extreme heat days (EHDs) with explicit consideration of the prevailing humidity. The piecewise multivariate bias correction method shows good fidelity in reproducing the frequency of different types of extreme heat events in the historical period. Projections for U.S. regions and individual cities for both the middle and end of the century are characterized by increases in the frequency of EHDs, and especially those characterized by high humidity. For many regions and individual cities, there is no overlap between the frequency of high‐humidity EHDs in general circulation model ensembles from the historical and future periods, indicating that increases in extreme heat are robust. Analysis of 500‐mb height, sea‐level pressure, and low‐level circulation composites for historical and future periods indicates that the Fifth Coupled Model Intercomparison Project models reproduce basic large‐scale circulation features associated with EHDs in U.S. regions and that future changes in extreme heat are related primarily to large‐scale warming rather than enhancement of regional circulation anomalies.
A New Efficient Method to Solve the Stream Power Law Model Taking Into Account Sediment Deposition
Authors: Yuan X. P. , Braun J. , Guerit L. , Rouby D. , Cordonnier G.
Published: April 2019

The stream power law model has been widely used to represent erosion by rivers but does not take into account the role played by sediment in modulating erosion and deposition rates. Davy and Lague (2009, https://doi.org/10.1029/2008JF001146) provide an approach to address this issue, but it is computationally demanding because the local balance between erosion and deposition depends on sediment flux resulting from net upstream erosion. Here, we propose an efficient (i.e., O(N) and implicit) method to solve their equation. This means that, unlike other methods used to study the complete dynamics of fluvial systems (e.g., including the transition from detachment‐limited to transport‐limited behavior), our method is unconditionally stable even when large time steps are used. We demonstrate its applicability by performing a range of simulations based on a simple setup composed of an uplifting region adjacent to a stable foreland basin. As uplift and erosion progress, the mean elevations of the uplifting relief and the foreland increase, together with the average slope in the foreland. Sediments aggrade in the foreland and prograde to reach the base level where sediments are allowed to leave the system. We show how the topography of the uplifting relief and the stratigraphy of the foreland basin are controlled by the efficiency of river erosion and the efficiency of sediment transport by rivers. We observe the formation of a steady‐state geometry in the uplifting region, and a dynamic steady state (i.e., autocyclic aggradation and incision) in the foreland, with aggradation and incision thicknesses up to tens of meters.
Significant Climate Impact of Highly Hygroscopic Atmospheric Aerosols in Delhi, India
Authors: Wang Yu , Chen Ying
Published: April 2019

Hygroscopicity of aerosol (κchem) is a key factor affecting its direct and indirect climate effects, however, long‐term observation in Delhi is absent. Here we demonstrate an approach to derive κchem from publicly available data sets and validate it (bias of 5%–30%) with long‐term observations in Beijing. Using this approach, we report the first estimation of κchem in Delhi and discuss its climate implications. The bulk‐averaged κchem of aerosols in Delhi is estimated to be 0.42 ± 0.07 during 2016–2018, implying a higher activation ability as cloud condensation nuclei in Delhi compared with Beijing and continental averages worldwide. To activate a 0.1‐μm particle, it averagely requires just a supersaturation of ~0.18% ± 0.015% in Delhi but ~0.3% (Beijing), 0.28%–0.31% (Asia, Africa, and South America) and ~0.22% (Europe and North America). Our results imply that representing κchem of Delhi using Asian/Beijing average may result in a significant underestimation of aerosol climate effects.
SRTM2gravity: An Ultrahigh Resolution Global Model of Gravimetric Terrain Corrections
Authors: Hirt Christian , Yang Meng , Kuhn Michael , Bucha Blažej , Kurzmann Andre , Pail Roland
Published: April 2019

We present a new global model of spherical gravimetric terrain corrections that take into account the gravitational attraction of Earth's global topographic masses at 3″ (~90 m) spatial resolution. The conversion of Shuttle Radar Topography Mission‐based digital elevation data to implied gravity effects relies on the global evaluation of Newton's law of gravitation, which represents a computational challenge for 3″ global topography data. We tackled this task by combining spatial and spectral gravity forward modeling techniques at the 0.2‐mGal accuracy level and used advanced computational resources in parallel to complete the 1 million CPU‐hour‐long computation within ~2 months. Key outcome is a 3″ map of topographic gravity effects reflecting the total gravitational attraction of Earth's global topography at ~28 billion computation points. The data, freely available for use in science, teaching, and industry, are immediately applicable as new in situ terrain correction to reduce gravimetric surveys around the globe.
Seasonal Water “Pump” in the Atmosphere of Mars: Vertical Transport to the Thermosphere
Authors: Shaposhnikov Dmitry S. , Medvedev Alexander S. , Rodin Alexander V. , Hartogh Paul
Published: April 2019

We present results of simulations with the Max Planck Institute Martian general circulation model implementing a hydrological cycle scheme. The simulations reveal a seasonal water “pump” mechanism responsible for the upward transport of water vapor. This mechanism occurs in high latitudes above 60° of the southern hemisphere at perihelion, when the upward branch of the meridional circulation is particularly strong. A combination of the mean vertical flux with variations induced by solar tides facilitates penetration of water across the “bottleneck” at approximately 60 km. The meridional circulation then transports water across the globe to the northern hemisphere. Since the intensity of the meridional cell is tightly controlled by airborne dust, the water abundance in the thermosphere strongly increases during dust storms.
Stress‐Induced Anomalous Transport in Natural Fracture Networks
Authors: Kang Peter K. , Lei Qinghua , Dentz Marco , Juanes Ruben
Published: April 2019

We investigate the effects of geological stress on fluid flow and tracer transport in natural fracture networks. We show the emergence of non‐Fickian (anomalous) transport from the interplay among fracture network geometry, aperture heterogeneity, and geological stress. In this study, we extract the fracture network geometry from the geological map of an actual rock outcrop, and we simulate the geomechanical behavior of fractured rock using a hybrid finite‐discrete element method. We analyze the impact of stress on the aperture distribution, fluid flow field, and tracer transport properties. Both stress magnitude and orientation have strong effects on the fracture aperture field, which in turn affects fluid flow and tracer transport through the system. We observe that stress anisotropy may cause significant shear dilation along long, curved fractures that are preferentially oriented to the stress loading. This, in turn, induces preferential flow paths and anomalous early arrival of tracers. An increase in stress magnitude enhances aperture heterogeneity by introducing more small apertures, which exacerbates late‐time tailing. This effect is stronger when there is higher heterogeneity in the initial aperture field. To honor the flow field with strong preferential flow paths, we extend the Bernoulli Continuous Time Random Walk model to incorporate dual velocity correlation length scales. The proposed upscaled transport model captures anomalous transport through stressed fracture networks and agrees quantitatively with the high‐fidelity numerical simulations.
Single cell fluorescence imaging of glycan uptake by intestinal bacteria
Authors: Hehemann Jan-Hendrik , Reintjes Greta , Klassen Leeann , Smith Adam D , Ndeh Didier , Arnosti Carol , Amann Rudolf , Abbott D Wade
Published: April 2019

Microbes in the intestines of mammals degrade dietary glycans for energy and growth. The pathways required for polysaccharide utilization are functionally diverse; moreover, they are unequally dispersed between bacterial genomes. Hence, assigning metabolic phenotypes to genotypes remains a challenge in microbiome research. Here we demonstrate that glycan uptake in gut bacteria can be visualized with fluorescent glycan conjugates (FGCs) using epifluorescence microscopy. Yeast α-mannan and rhamnogalacturonan-II, two structurally distinct glycans from the cell walls of yeast and plants, respectively, were fluorescently labeled and fed to Bacteroides thetaiotaomicron VPI-5482. Wild-type cells rapidly consumed the FGCs and became fluorescent; whereas, strains that had deleted pathways for glycan degradation and transport were non-fluorescent. Uptake of FGCs, therefore, is direct evidence of genetic function and provides a direct method to assess specific glycan metabolism in intestinal bacteria at the single cell level.
Enhanced discriminative aversive learning and amygdala responsivity in 5-HT transporter mutant mice
Authors: Lima João , Sharp Trevor , Bannerman David M. , McHugh Stephen B.
Published: April 2019

Genetic variation in the human serotonin transporter (5-HTT) has been linked to altered fear learning but the data are inconsistent and the mechanism is unclear. The present study investigated conditioned aversive learning in 5-HTT knockout (KO) mice while simultaneously recording neural network activity (theta oscillations) and hemodynamic responses (tissue oxygen delivery) from the amygdala, a brain region necessary for forming fearful memories. Conditioned aversive learning was measured using a discrimination learning task in which one auditory cue was paired with foot-shock, whereas a second auditory cue was not. Compared with wild-type mice, 5-HTTKO mice exhibited faster discrimination learning. This effect was associated with stronger theta frequency oscillations and greater hemodynamic changes in the amygdala in response to both the emotionally relevant cues and the unconditioned foot-shock stimulus. Furthermore, hemodynamic responses to the unconditioned stimulus predicted behavioral discrimination performance the following day. Acute pharmacological 5-HTT blockade in wild-type mice produced a similar effect, to the extent that administration of citalopram during the fear conditioning sessions enhanced fear memory recall. Collectively, our data argue that loss of 5-HTT function enhances amygdala responsivity to aversive events and facilitates learning for emotionally relevant cues.
Small molecule electro-optical binding assay using nanopores
Authors: Cai Shenglin , Sze Jasmine Y. Y. , Ivanov Aleksandar P. , Edel Joshua B.
Published: April 2019

The identification of short nucleic acids and proteins at the single molecule level is a major driving force for the development of novel detection strategies. Nanopore sensing has been gaining in prominence due to its label-free operation and single molecule sensitivity. However, it remains challenging to detect small molecules selectively. Here we propose to combine the electrical sensing modality of a nanopore with fluorescence-based detection. Selectivity is achieved by grafting either molecular beacons, complementary DNA, or proteins to a DNA molecular carrier. We show that the fraction of synchronised events between the electrical and optical channels, can be used to perform single molecule binding assays without the need to directly label the analyte. Such a strategy can be used to detect targets in complex biological fluids such as human serum and urine. Future optimisation of this technology may enable novel assays for quantitative protein detection as well as gene mutation analysis with applications in next-generation clinical sample analysis.
Therapeutic role of miR-19a/19b in cardiac regeneration and protection from myocardial infarction
Authors: Gao Feng , Kataoka Masaharu , Liu Ning , Liang Tian , Huang Zhan-Peng , Gu Fei , Ding Jian , Liu Jianming , Zhang Feng , Ma Qing , Wang Yingchao , Zhang Mingming , Hu Xiaoyun , Kyselovic Jan , Hu Xinyang , Pu William T. , Wang Jian’an , Chen Jinghai , Wang Da-Zhi
Published: April 2019

The primary cause of heart failure is the loss of cardiomyocytes in the diseased adult heart. Previously, we reported that the miR-17-92 cluster plays a key role in cardiomyocyte proliferation. Here, we report that expression of miR-19a/19b, members of the miR-17-92 cluster, is induced in heart failure patients. We show that intra-cardiac injection of miR-19a/19b mimics enhances cardiomyocyte proliferation and stimulates cardiac regeneration in response to myocardial infarction (MI) injury. miR-19a/19b protected the adult heart in two distinctive phases: an early phase immediately after MI and long-term protection. Genome-wide transcriptome analysis demonstrates that genes related to the immune response are repressed by miR-19a/19b. Using an adeno-associated virus approach, we validate that miR-19a/19b reduces MI-induced cardiac damage and protects cardiac function. Finally, we confirm the therapeutic potential of miR-19a/19b in protecting cardiac function by systemically delivering miR-19a/19b into mice post-MI. Our study establishes miR-19a/19b as potential therapeutic targets to treat heart failure.
Major vault protein suppresses obesity and atherosclerosis through inhibiting IKK–NF-κB signaling mediated inflammation
Authors: Ben Jingjing , Jiang Bin , Wang Dongdong , Liu Qingling , Zhang Yongjing , Qi Yu , Tong Xing , Chen Lili , Liu Xianzhong , Zhang Yan , Zhu Xudong , Li Xiaoyu , Zhang Hanwen , Bai Hui , Yang Qing , Ma Junqing , Wiemer Erik A. C. , Xu Yong , Chen Qi
Published: April 2019

Macrophage-orchestrated, low-grade chronic inflammation plays a pivotal role in obesity and atherogenesis. However, the underlying regulatory mechanisms remain incompletely understood. Here, we identify major vault protein (MVP), the main component of unique cellular ribonucleoprotein particles, as a suppressor for NF-κB signaling in macrophages. Both global and myeloid-specific MVP gene knockout aggravates high-fat diet induced obesity, insulin resistance, hepatic steatosis and atherosclerosis in mice. The exacerbated metabolic disorders caused by MVP deficiency are accompanied with increased macrophage infiltration and heightened inflammatory responses in the microenvironments. In vitro studies reveal that MVP interacts with TRAF6 preventing its recruitment to IRAK1 and subsequent oligomerization and ubiquitination. Overexpression of MVP and its α-helical domain inhibits the activity of TRAF6 and suppresses macrophage inflammation. Our results demonstrate that macrophage MVP constitutes a key constraint of NF-κB signaling thereby suppressing metabolic diseases.
Bacterial glycosyltransferase-mediated cell-surface chemoenzymatic glycan modification
Authors: Hong Senlian , Shi Yujie , Wu Nicholas C. , Grande Geramie , Douthit Lacey , Wang Hua , Zhou Wen , Sharpless K. Barry , Wilson Ian A. , Xie Jia , Wu Peng
Published: April 2019

Chemoenzymatic modification of cell-surface glycan structures has emerged as a complementary approach to metabolic oligosaccharide engineering. Here, we identify Pasteurella multocida α2-3-sialyltransferase M144D mutant, Photobacterium damsela α2-6-sialyltransferase, and Helicobacter mustelae α1-2-fucosyltransferase, as efficient tools for live-cell glycan modification. Combining these enzymes with Helicobacter pylori α1-3-fucosyltransferase, we develop a host-cell-based assay to probe glycan-mediated influenza A virus (IAV) infection including wild-type and mutant strains of H1N1 and H3N2 subtypes. At high NeuAcα2-6-Gal levels, the IAV-induced host-cell death is positively correlated with haemagglutinin (HA) binding affinity to NeuAcα2-6-Gal. Remarkably, an increment of host-cell-surface sialyl Lewis X (sLeX) exacerbates the killing by several wild-type IAV strains and a previously engineered mutant HK68-MTA. Structural alignment of HAs from HK68 and HK68-MTA suggests formation of a putative hydrogen bond between Trp222 of HA-HK68-MTA and the C-4 hydroxyl group of the α1-3-linked fucose of sLeX, which may account for the enhanced host cell killing of that mutant.
Hydrophobic carbon dots with blue dispersed emission and red aggregation-induced emission
Authors: Yang Haiyao , Liu Yingliang , Guo Zhouyi , Lei Bingfu , Zhuang Jianle , Zhang Xuejie , Liu Zhiming , Hu Chaofan
Published: April 2019

Carbon dots (CDs) have been studied for years as one of the most promising fluorescent nanomaterials. However, CDs with red or solid-state fluorescence are rarely reported. Herein, through a one-pot solvothermal treatment, hydrophobic CDs (H-CDs) with blue dispersed emission and red aggregation-induced emission are obtained. When water is introduced, the hydrophobic interaction leads to aggregation of the H-CDs. The formation of H-CD clusters induces the turning off of the blue emission, as the carbonized cores suffer from π-π stacking interactions, and the turning on of the red fluorescence, due to restriction of the surfaces’ intramolecular rotation around disulfide bonds, which conforms to the aggregation-induced-emission phenomenon. This on-off fluorescence of the H-CDs is reversible when the H-CD powder is completely dissolved. Moreover, the H-CD solution dispersed in filter paper is nearly colorless. Finally, we develop a reversible two switch-mode luminescence ink for advanced anti-counterfeiting and dual-encryption.
Author Correction: One-plasmid double-expression His-tag system for rapid production and easy purification of MS2 phage-like particles
Authors: Mikel Pavel , Vasickova Petra , Kralik Petr
Published: April 2019

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.
Author Correction: Reply to ‘Sigmoidal Acquisition Curves are Good Indicators of Conformist Transmission’
Authors: Acerbi Alberto , van Leeuwen Edwin J. C. , Haun Daniel B. M. , Tennie Claudio
Published: April 2019

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.