bluuebunny/crossref_metadata_2025 huggingface dataset:
Probability density functions for fluctuations in turbulent two-phase flames
Authors: Borghi R. , Anselmet F.
Published: March 2021

Probability density function methods for characterizing various fluctuating quantities in the reacting gas phase of turbulent spray flames are presented, for the development of which O'Brien has been a pioneer. Balance equations for two-phase flows considered as a piecewise continuous medium are first presented with the interface conditions containing the vaporization–condensation equilibrium. From these, the equation for the joint probability density function of temperature and composition in the gas phase is derived, in which specific terms related to vaporization are identified. The terms that require modeling are then highlighted. The first one is the classical micromixing term, which has to include all the features already discussed for single phase reacting flows, but adaptation to two-phase flows has to be questioned. Mainly, several unclosed terms deal with vaporization, requiring specific attention. It is shown that proposals for their modeling can be obtained on the same basis as in the so-called Eulerian–Lagrangian models, which will directly induce changes in the shape of the probability density function. We finally discuss the model presented herein and comment on its connection with recently published literature for this subject. Specific attention is devoted to the combustion regimes and to the presence of diffusion flamelets surrounding fuel droplets or groups of droplets. The proposals presented here go one step further compared to the recent studies, and now, they have to be compared with well-defined experiments, numerical experiments with direct numerical simulations, or real experiments in conveniently controlled conditions.
Direct numerical simulation of supercritical oxy-methane mixing layers with CO2 substituted counterparts
Authors: Ovais Syed Mohammad , Kemenov Konstantin A. , Miller Richard S.
Published: March 2021

Direct numerical simulations of temporally developing, three-dimensional, CH4/CO2, CH4/O2, and CO2/O2 mixing layers are conducted at a supercritical pressure of 300 atm. To effectively model the supercritical regime, the employed formulation includes the compressible form of the governing equations, the cubic Peng–Robinson equation of state and a generalized formulation for heat and mass flux vectors derived from non-equilibrium thermodynamics and fluctuation theory. A linear inviscid stability analysis is also performed for each case, to determine its most unstable wavelength. Flow visualizations reveal the presence of high density gradient magnitude regions for all three mixing layers, with conditional averages indicating increased presence of heavier fluid species within these regions. No significant departures are observed from perfect gas behavior, with compressibility factors very close to unity for all three mixing cases. Applicability of presumed probability density function methods is examined for the three supercritical mixing layers. An a priori analysis is also conducted to investigate various simplifying assumptions employed in modeling various subgrid scale (SGS) flux models. Two additional terms are identified in the large eddy simulation equations, the gradient of SGS contribution of pressure in the momentum equation and the gradient of SGS contribution of heat flux in energy equation, whose magnitudes are similar and comparable with their respective resolved terms. The performance of the scale similarity model to represent these additional terms is investigated. Finally, the performance of Smagorinsky, gradient, and scale similarity models is also investigated.
Dispersive sensing of charge states in a bilayer graphene quantum dot
Authors: Banszerus L. , Möller S. , Icking E. , Steiner C. , Neumaier D. , Otto M. , Watanabe K. , Taniguchi T. , Volk C. , Stampfer C.
Published: March 2021

We demonstrate dispersive readout of individual charge states in a gate-defined few-electron quantum dot in bilayer graphene. We employ a radio frequency reflectometry circuit, where an LC resonator with a resonance frequency close to 280 MHz is directly coupled to an Ohmic contact of the quantum dot device. The detection scheme based on changes in the quantum capacitance operates over a wide gate-voltage range and allows us to probe excited states down to the single-electron regime. Crucially, the presented sensing technique avoids the use of an additional, capacitively coupled quantum device such as a quantum point contact or single electron transistor, making dispersive sensing particularly interesting for gate-defined graphene quantum dots.
An enhanced dual-resonator metamaterial beam for low-frequency vibration suppression
Authors: Bao Huihuang , Wu Chuanyu , Wang Ke , Yan Bo
Published: March 2021

Structural vibrations seriously affect the working performance of and even cause fatal hazards in host structures. The use of a metamaterial is a novel way to suppress structural vibrations across a wide frequency band. This paper presents an enhanced dual-resonator metamaterial beam (DRMB), where the free end of a traditional series dual-resonator is periodically connected to the rigid body with a spring. The mass and frequency response of the enhanced dual-resonator is derived. The theoretical dispersion relation and band structure are obtained using a transfer matrix method. The effects of the number of cells, mass ratio, and spring stiffness ratio on the bandgap and transmissibility performance of the proposed DRMB are analyzed and discussed. An experiment is carried out to verify the theoretical model. The results show that with increasing number of cells, mass ratio, and spring stiffness ratio of the DRMB, the bandgap changes significantly, thereby enhancing the vibration suppression performance in a low-frequency range. The dual-resonator with three springs suppresses beam vibration.
Thermal performance analysis for moderate Rayleigh numbers of Newtonian hybrid nanofluid-filled U-shaped cavity with various thermal profiles
Authors: Asmadi M. S. , Md. Kasmani R. , Siri Z. , Saleh H.
Published: March 2021

The numerical study of natural convection heat transfer inside a U-shaped enclosure with various thermal profiles by using copper–alumina/water hybrid nanofluid is reported. The study focuses on the effect of constant, linear, quadratic, and sinusoidal with different amplitudes and periods and absolute sinusoidal thermal profiles to the heat transfer efficiency inside the lid. A weighted residual Galerkin triangular finite element method is used alongside the damped Newton–Raphson algorithm to calculate the heat transfer rate of the system in terms of averaged and local Nusselt number. The result from the present model is compared with the previously published experimental and numerical data. The isotherms and streamlines of the fluid flow for each thermal profile are presented with a nanoparticle volume fraction of between 0 and 0.1 for Rayleigh number of 104–106. It is found that the constant heating profile gives the best heat dissipation performance, while the sinusoidal thermal profile performed the worst. The results gained from this paper will be useful in understanding how heat can be transferred effectively as it can be applied to many different industries, including the electronics field.
Probability of COVID-19 infection by cough of a normal person and a super-spreader
Authors: Agrawal Amit , Bhardwaj Rajneesh
Published: March 2021

In this work, we estimate the probability of an infected person infecting another person in the vicinity by coughing in the context of COVID-19. The analysis relies on the experimental data of Simha and Rao [“Universal trends in human cough airflows at large distances,” Phys. Fluids 32, 081905 (2020)] and similarity analysis of Agrawal and Bhardwaj [“Reducing chances of COVID-19 infection by a cough cloud in a closed space,” Phys. Fluids 32, 101704 (2020)] to determine the variation of the concentration of infected aerosols with some distance from the source. The analysis reveals a large probability of infection within the volume of the cough cloud and a rapid exponential decay beyond it. The benefit of using a mask is clearly brought out through a reduction in the probability of infection. The increase in the probability of transmission by a super-spreader is also quantified for the first time. At a distance of 1 m, the probability of infection from a super-spreader is found to be 185% larger than a normal person. Our results support the current recommendation of maintaining a 2 m distance between two people. The analysis is enough to be applied to the transmission of other diseases by coughing, while the probability of transmission of COVID-19 due to other respiratory events can be obtained using our proposed approach.
CAS without SCF—Why to use CASCI and where to get the orbitals
Authors: Levine Benjamin G. , Durden Andrew S. , Esch Michael P. , Liang Fangchun , Shu Yinan
Published: March 2021

The complete active space self-consistent field (CASSCF) method has seen broad adoption due to its ability to describe the electronic structure of both the ground and excited states of molecules over a broader swath of the potential energy surface than is possible with the simpler Hartree–Fock approximation. However, it also has a reputation for being unwieldy, computationally costly, and un-black-box. Here, we discuss a class of alternatives, complete active space configuration interaction (CASCI) methods, paying particular attention to their application to electronic excited states. The goal of this Perspective is fourfold. First, we argue that CASCI is not merely an approximation to CASSCF, in that it can be designed to have important qualitative advantages over CASSCF. Second, we present several insights drawn from our experience experimenting with different schemes for computing orbitals to be employed in CASCI. Third, we argue that CASCI is well suited for application to nanomaterials. Finally, we reason that, with the rise in new low-scaling approaches for describing multireference systems, there is a greater need than ever to develop new methods for defining orbitals that provide an efficient and accurate description of both static correlation and electronic excitations in a limited active space.
The Gregory–Laflamme instability of the Schwarzschild black string exterior
Authors: Collingbourne Sam C.
Published: March 2021

In this paper, a direct rigorous mathematical proof of the Gregory–Laflamme instability for the five-dimensional Schwarzschild black string is presented. Under a choice of ansatz for the perturbation and a gauge choice, the linearized vacuum Einstein equation reduces to an ordinary differential equation (ODE) problem for a single function. In this work, a suitable rescaling and change of variables is applied, which casts the ODE into a Schrödinger eigenvalue equation to which an energy functional is assigned. It is then shown by direct variational methods that the lowest eigenfunction gives rise to an exponentially growing mode solution, which has admissible behavior at the future event horizon and spacelike infinity. After the addition of a pure gauge solution, this gives rise to a regular exponentially growing mode solution of the linearized vacuum Einstein equation in harmonic/transverse-traceless gauge.
Domain wall mobility engineering by a perpendicular magnetic field in microwires with a gradient of perpendicular anisotropy
Authors: Fecova L. , Richter K. , Varga R.
Published: March 2021

Fast domain wall propagation is a typical feature of amorphous glass-coated microwires with positive magnetostriction. The high domain wall velocity can be effectively tailored either by sample postprocessing or temperature. In this work, we show that the domain wall dynamics can be engineered by a perpendicular magnetic field. We perform the domain wall mobility measurements in microwires with a varying gradient of the perpendicular magnetic anisotropy. It is shown that domain wall mobility is mainly determined by counterplay between the amplitude of perpendicular anisotropy and externally applied perpendicular field. The presence of perpendicular magnetic anisotropy is observed by Scanning electron microscopy. The relation between the maximum applied perpendicular magnetic field, and the wire dimensions are provided based on the measured data.
Negative regulation of plastidial isoprenoid pathway by herbivore-induced β-cyclocitral in
Arabidopsis thaliana
Authors: Mitra Sirsha , Estrada-Tejedor Roger , Volke Daniel C. , Phillips Michael A. , Gershenzon Jonathan , Wright Louwrance P.
Published: March 2021

Significance

Plants are known to respond to insect herbivory in multiple ways. Under herbivore attack, plants increase their commitment to defense but decrease their commitment to growth and carbon assimilation. Unfortunately, this second aspect is less studied. Here we report the discovery of an herbivore-triggered signal (β-cyclocitral) that enhances plant resistance and down-regulates the methylerythritol-4-phosphate (MEP) pathway of terpenoid biosynthesis. The MEP pathway supplies the precursors for many metabolites important in photosynthesis such as chlorophylls, carotenoids, plastoquinones, phylloquinones, and tocopherols. We also elucidated the mechanism responsible for the reduction of MEP pathway flux under herbivory and found that β-cyclocitral inhibits the activity of the first step of the pathway, which was also shown to control flux under normal growth conditions.
Complexity and graded regulation of neuronal cell-type–specific alternative splicing revealed by single-cell RNA sequencing
Authors: Feng Huijuan , Moakley Daniel F. , Chen Shuonan , McKenzie Melissa G. , Menon Vilas , Zhang Chaolin
Published: March 2021

Significance

Alternative splicing (AS) is extensively used in the mammalian brain, but its contribution to the molecular and cellular diversity across neuronal cell types remains poorly understood. Through systematic and integrative analysis of over 100 transcriptomically defined cortical neuronal types, we found neuronal subclass-specific splicing-regulatory programs consist of overlapping alternative exons showing differential splicing at multiple hierarchical levels. Evidence is provided that this graded AS regulation is controlled by unique combinations of RNA-binding proteins (RBPs). Importantly, these RBPs also contribute to splicing dynamics across neuronal cell types that do not conform to the hierarchical taxonomy established based on transcriptional profiles, suggesting that the graded AS regulation may provide a molecular mechanism orthogonal to transcriptional regulation in specifying neuronal identity and function.
Seipin accumulates and traps diacylglycerols and triglycerides in its ring-like structure
Authors: Zoni Valeria , Khaddaj Rasha , Lukmantara Ivan , Shinoda Wataru , Yang Hongyuan , Schneiter Roger , Vanni Stefano
Published: March 2021

Significance

Metabolic disorders related to aberrant fat accumulation, including lipodystrophy and obesity, are a serious health concern. Inside cells, fat accumulates in organelles named lipid droplets (LDs). LDs form in the endoplasmic reticulum (ER), where triglycerides (TG), the most abundant form of fat, are produced. The Berardinelli–Seip congenital lipodystrophy type 2 protein, seipin, has been identified as a key regulator of LD formation, but its mechanism of action remains debated and its molecular details mostly obscure. Here, we use molecular dynamics simulations to investigate the mechanism of seipin action. We find that seipin clusters and traps both TG and its precursor, diacylglycerol. Our results suggest that seipin organizes the lipid composition of specific ER sites to prime them for LD biogenesis.
POLArIS, a versatile probe for molecular orientation, revealed actin filaments associated with microtubule asters in early embryos
Authors: Sugizaki Ayana , Sato Keisuke , Chiba Kazuyoshi , Saito Kenta , Kawagishi Masahiko , Tomabechi Yuri , Mehta Shalin B. , Ishii Hirokazu , Sakai Naoki , Shirouzu Mikako , Tani Tomomi , Terada Sumio
Published: March 2021

Significance

Monitoring orientation of biological molecules in living cells is a key approach to understanding the mechanisms of emergence/dissolution of molecular architectures. However, it has been challenging due to lack of general methodologies that can be used for living cells. We developed POLArIS, a genetically encoded and versatile probe for molecular orientation imaging. POLArIS is a recombinant binder rigidly connected to a fluorescent protein and can target biomolecules of interest by combining with phage display screening. Live imaging of starfish embryos expressing POLArIS that specifically binds to F-actin revealed that actin filaments radially extend in association with microtubule asters during mitosis. POLArIS can be applied in a variety of living specimens including whole bodies of or specific cell types in animals.
Pressure Driven Structural Evolutions of 0.935(Na0.5Bi0.5)TiO3-0.065BaTiO3 Lead-Free Ferroelectric Single Crystal through Raman Spectroscopy
Authors: Zheng Qunfei , Li Qiang , Xue Saidong , Wu Yanhui , Wang Lijuan , Zhang Qian , Qin Xiaomei , Zhao Xiangyong , Wang Feifei , Yang Wenge
Published: March 2021

Pressure evolution of local structure and vibrational dynamics of the perovskite-type relaxor ferroelectric single crystal of 0.935(Na0.5Bi0.5)TiO3-0.065BaTiO3 (NBT-6.5BT) is systematically investigated via in situ Raman spectroscopy. The pressure dependence of phonon modes up to 30 GPa reveals two characteristic pressures: one is at around 4.6 GPa which corresponds to the rhombohedral-to-tetragonal phase transition, showing that the pressure strongly suppresses the coupling between the off-centered A- and B-site cations; the other structural transition involving the oxygen octahedral tilt and vibration occurs at pressure ∼13–15 GPa with certain degree of order-disorder transition, evidenced by the abnormal changes of intensity and FWHM in Raman spectrum.
Directional Design of Materials Based on Multi-Objective Optimization: A Case Study of Two-Dimensional Thermoelectric SnSe
Authors: Yan Shenshen , Wang Yi , Gao Zhibin , Long Yang , Ren Jie
Published: March 2021

The directional design of functional materials with multi-objective constraints is a big challenge, in which performance and stability are determined by a complicated interconnection of different physical factors. We apply multi-objective optimization, based on the Pareto Efficiency and Particle-Swarm Optimization methods, to design new functional materials directionally. As a demonstration, we achieve the thermoelectric design of 2D SnSe materials via the above methods. We identify several novel metastable 2D SnSe structures with simultaneously lower free energy and better thermoelectric performance in their experimentally reported monolayer structures. We hope that the results of our work on the multi-objective Pareto Optimization method will represent a step forward in the integrative design of future multi-objective and multi-functional materials.
Metal-Element-Incorporation Induced Superconducting Hydrogen Clathrate Structure at High Pressure
Authors: Ma Jiayu , Kuang Junlin , Cui Wenwen , Chen Ju , Gao Kun , Hao Jian , Shi Jingming , Li Yinwei
Published: March 2021

The recent observation of high critical temperature T
c in lanthanum and Yttrium hydrides confirms the key role of hydrogen cage (H-cage) in determining high superconductivity. Here, we present a new class of metastable H12 clathrate structures based on the icosahedral cI24-Na that can be stabilized by incorporation of metal elements. Analysis shows that the charge transfer from metal atoms to H atoms contributes to forming the H12 clathrate. Nine dynamically stable structures are identified to exhibit superconductivity, and a maximum T
c of 28 K is found in voids-doped Mo6H24. Calculations reveal that the low T
c is attributed to the weak interaction between H atoms in each cage due to the long H–H distance. The current results provide a possible route to design H-cage containing superconductors.
Wide-Angle Ultra-Broadband Metamaterial Absorber with Polarization-Insensitive Characteristics
Authors: Chen Peng , Kong Xianglin , Han Jianfei , Wang Weihua , Han Kui , Ma Hongyu , Zhao Lei , Shen Xiaopeng
Published: March 2021

An ultra-wideband metamaterial absorber is developed, which is polarized-insensitive and angular-stable. Three layers of square resistive films comprise the proposed metamaterial. The optimal values of geometric parameters are obtained, such that the designed absorber can achieve an ultra-broadband absorption response from 4.73 to 39.04 GHz (relative bandwidth of 156.7%) for both transverse electricity and transverse magnetic waves. Moreover, impedance matching theory and an equivalent circuit model are utilized for the absorption mechanism analysis. The compatibility of equivalent circuit calculation results, together with both full-wave simulation and experimental results, demonstrates the excellent performance and applicability of the proposed metamaterial absorber.
Design of a Class of New sp
2 – sp
3 Carbons Constructed by Graphite and Diamond Building Blocks
Authors: Luo Kun , Liu Bing , Sun Lei , Zhao Zhisheng , Tian Yongjun
Published: March 2021

The sp
2–sp
3-hybridized carbon allotropes with the advantage of two hybrid structures possess rich and fascinating electronic and mechanical properties and they have received long-standing attention. We design a class of versatile sp
2–sp
3 carbons composed of graphite and diamond structural units with variable sizes. This class of sp
2–sp
3 carbons is energetically more favorable than graphite under high pressure, and their mechanical and dynamical stabilities are further confirmed at ambient pressure. The calculations of band structure and mechanical properties indicate that this class of sp
2–sp
3 carbons not only exhibits peculiar electronic characteristics adjusted from semiconducting to metallic nature but also presents excellent mechanical characteristics, such as superhigh hardness and high ductility. These sp
2–sp
3 carbons have desirable properties across a broad range of potential applications.
Nodal superconducting gap in LiFeP revealed by NMR: Contrast with LiFeAs*
Authors: Fang A F , Zhou R , Tukada H , Yang J , Deng Z , Wang X C , Jin C Q , Zheng Guo-Qing
Published: March 2021

Identifying the uniqueness of FeP-based superconductors may shed new lights on the mechanism of superconductivity in iron-pnictides. Here, we report nuclear magnetic resonance (NMR) studies on LiFeP and LiFeAs which have the same crystal structure but different pnictogen atoms. The NMR spectrum is sensitive to inhomogeneous magnetic fields in the vortex state and can provide the information on the superconducting pairing symmetry through the temperature dependence of London penetration depth λ
L. We find that λ
L saturates below T ∼ 0.2 T
c in LiFeAs, where T
c is the superconducting transition temperature, indicating nodeless superconducting gaps. Furthermore, by using a two-gaps model, we simulate the temperature dependence of λ
L and obtain the superconducting gaps of LiFeAs, as Δ
1 = 1.2 k
B
T
c and Δ2 = 2.8 k
B
T
c, in agreement with previous result from spin-lattice relaxation. For LiFeP, in contrast, λ
L does not show any saturation down to T ∼ 0.03 T
c, indicating nodes in the superconducting gap function. Finally, we demonstrate that strong spin fluctuations with diffusive characteristics exist in LiFeP, as in some cuprate high temperature superconductors.
Laser induced fluorescence diagnostic for velocity distribution functions: applications, physics, methods and developments
Authors: YIP Chi-Shung , JIANG Di
Published: March 2021

With more than 30 years of development, laser-induced fluorescence (LIF) is becoming an increasingly common diagnostic to measure ion and neutral velocity distribution functions in different fields of studies in plasma science including Hall thrusters, linear devices, plasma processing, and basic plasma physical processes. In this paper, technical methods used in the LIF diagnostic, including modulation, collection optics, and wavelength calibration techniques are reviewed in detail. A few basic physical processes along with applications and future development associated with the LIF diagnostics are also reviewed.
Mutant Nmnat1 leads to a retina-specific decrease of NAD+ accompanied by increased poly(ADP-ribose) in a mouse model of NMNAT1-associated retinal degeneration
Authors: Greenwald Scott H , Brown Emily E , Scandura Michael J , Hennessey Erin , Farmer Raymond , Du Jianhai , Wang Yekai , Pierce Eric A
Published: March 2021

Nicotinamide mononucleotide adenylyltransferase 1 (NMNAT1) is required for nuclear nicotinamide adenine mononucleotide (NAD+) biosynthesis in all nucleated cells, and despite its functional ubiquity, mutations in this gene lead to an isolated retinal degeneration. The mechanisms underlying how mutant NMNAT1 causes disease are not well understood, nor is the reason why the pathology is confined to the retina. Using a mouse model of NMNAT1-associated retinal degeneration that harbors the p.Val9Met mutation, we tested the hypothesis that decreased function of mutant NMNAT1 has a greater effect on the levels of NAD+ in the retina than elsewhere in the body. Measurements by liquid chromatography with tandem mass spectrometry showed an early and sustained decrease of NAD+ in mutant retinas that was not observed in other tissues. To understand how consumers of nuclear NAD+ are affected by the reduced availability of NAD+ in mutant retinas, poly(ADP-ribose) polymerase (PARP) and nuclear sirtuin activity were evaluated. PARP activity was elevated during disease progression, as evidenced by overproduction of poly(ADP-ribose) (PAR) in photoreceptors, whereas histone deacetylation activity of nuclear sirtuins was not altered. We hypothesized that PARP could be activated because of elevated levels of oxidative stress; however, we did not observe oxidative DNA damage, lipid peroxidation, or a low glutathione to oxidized glutathione ratio. Terminal deoxynucleotidyl transferase dUTP nick end labeling staining revealed that photoreceptors appear to ultimately die by apoptosis, although the low NAD+ levels and overproduction of PAR suggest that cell death may include aspects of the parthanatos cell death pathway.
Disruption of Long-Term Depression Potentiates Latent Inhibition: Key Role for Central Nucleus of the Amygdala
Authors: Ashby Donovan M , Dias Carine , Aleksandrova Lily R , Lapish Christopher C , Wang Yu Tian , Phillips Anthony G
Published: March 2021

Background

Latent inhibition (LI) reflects an adaptive form of learning impaired in certain forms of mental illness. Glutamate receptor activity is linked to LI, but the potential role of synaptic plasticity remains unspecified.

Methods

Accordingly, the present study examined the possible role of long-term depression (LTD) in LI induced by prior exposure of rats to an auditory stimulus used subsequently as a conditional stimulus to signal a pending footshock. We employed 2 mechanistically distinct LTD inhibitors, the Tat-GluA23Y peptide that blocks endocytosis of the GluA2-containing glutamate α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor, or the selective glutamate n-methyl-d-aspartate receptor 2B antagonist, Ro25-6981, administered prior to the acquisition of 2-way conditioned avoidance with or without tone pre-exposure.

Results

Systemic LTD blockade with the Tat-GluA23Y peptide strengthened the LI effect by further impairing acquisition of conditioned avoidance in conditional stimulus-preexposed rats compared with normal conditioning in non-preexposed controls. Systemic Ro25-6981 had no significant effects. Brain region–specific microinjections of the Tat-GluA23Y peptide into the nucleus accumbens, medial prefrontal cortex, or central or basolateral amygdala demonstrated that disruption of glutamate α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor endocytosis in the central amygdala also potentiated the LI effect.

Conclusions

These data revealed a previously unknown role for central amygdala LTD in LI as a key mediator of cognitive flexibility required to respond to previously irrelevant stimuli that acquire significance through reinforcement. The findings may have relevance both for our mechanistic understanding of LI and its alteration in disease states such as schizophrenia, while further elucidating the role of LTD in learning and memory.
Monetary Incentives in Large-Scale Face-to-Face Surveys: Evidence from a Series of Experiments
Authors: Blohm Michael , Koch Achim
Published: March 2021

Monetary respondent incentives are a means to counteract the trend toward declining response rates. This article summarizes the results of a series of experiments conducted in the past decade in the German General Social Survey. We found that prepaid monetary incentives led to a higher increase in response than promised incentives. There was no evidence that either promised or prepaid incentives had a systematic effect on sample composition. The incentives helped to reduce fieldwork efforts. Thus, the costs of incentives can—at least partially—be offset by a reduction in the number of contact attempts required to achieve a certain number of completed interviews. Our findings are highly credible due to the replicative design of the experiments.
Partial Regularity of Harmonic Maps From Alexandrov Spaces
Authors: Ge Huabin , Jiang Wenshuai , Zhang Hui-Chun
Published: March 2021

In this paper, we prove the Lipschitz regularity of continuous harmonic maps from a finite-dimensional Alexandrov space to a compact smooth Riemannian manifold. This solves a conjecture of F. H. Lin in [38]. The proof extends the argument of Huang-Wang [28].
Use of machine learning to predict clinical decision support compliance, reduce alert burden, and evaluate duplicate laboratory test ordering alerts
Authors: Baron Jason M , Huang Richard , McEvoy Dustin , Dighe Anand S
Published: March 2021

Objectives

While well-designed clinical decision support (CDS) alerts can improve patient care, utilization management, and population health, excessive alerting may be counterproductive, leading to clinician burden and alert fatigue. We sought to develop machine learning models to predict whether a clinician will accept the advice provided by a CDS alert. Such models could reduce alert burden by targeting CDS alerts to specific cases where they are most likely to be effective.

Materials and Methods

We focused on a set of laboratory test ordering alerts, deployed at 8 hospitals within the Partners Healthcare System. The alerts notified clinicians of duplicate laboratory test orders and advised discontinuation. We captured key attributes surrounding 60 399 alert firings, including clinician and patient variables, and whether the clinician complied with the alert. Using these data, we developed logistic regression models to predict alert compliance.

Results

We identified key factors that predicted alert compliance; for example, clinicians were less likely to comply with duplicate test alerts triggered in patients with a prior abnormal result for the test or in the context of a nonvisit-based encounter (eg, phone call). Likewise, differences in practice patterns between clinicians appeared to impact alert compliance. Our best-performing predictive model achieved an area under the receiver operating characteristic curve (AUC) of 0.82. Incorporating this model into the alerting logic could have averted more than 1900 alerts at a cost of fewer than 200 additional duplicate tests.

Conclusions

Deploying predictive models to target CDS alerts may substantially reduce clinician alert burden while maintaining most or all the CDS benefit.
Assessment of Semiochemical Repellents for Protecting Walnut Trees From Walnut Twig Beetle (Coleoptera: Curculionidae) Attack in a Commercial Orchard Setting in California
Authors: Audley Jackson P , Bostock Richard M , Seybold Steven J
Published: March 2021

The walnut twig beetle, Pityophthorus juglandis Blackman, the vector of thousand cankers disease (TCD), poses a significant threat to North American walnut (Juglandaceae Juglans) trees. Despite discovery of TCD-related tree mortality over a decade ago, management options are lacking. This study represents the culmination of several years of investigating the chemical ecology of P. juglandis in hopes of developing a semiochemical repellent to disrupt the beetle’s host colonization and aggregation behaviors. Numbers of P. juglandis landing on semiochemical-treated Juglans regia L. trees in a commercial walnut orchard were compared based on captures on sticky traps. Two repellent combinations were tested: R-(+)-limonene and trans-conophthorin (LimeCon), and R-(+)-limonene, trans-conophthorin, and R-(+)-verbenone (LCV). Both repellents reduced P. juglandis aggregation (captures) equally; thus, we proceeded with the LimeCon combination to reduce potential treatment cost. Subsequent trials included a 2× dose (Dual) of LimeCon. Both LimeCon and Dual significantly reduced the number of P. juglandis caught compared with the baited control, however, only for the lower of two trap positions. Beetle landings were modeled by trap distance from repellent placement on each tree. Beetle responses to the pheromone lure were surprisingly localized and did not bring the whole tree under attack. LimeCon, LCV, and Dual treatments averaged fewer than a single beetle caught for all trap distances; however, performance of the repellents beyond 150 cm is not clear due to the localized landing response of P. juglandis to pheromone lures. Further testing is required to fully analyze the zone of inhibition of the LimeCon repellent.
Risk factors of post-operative pneumonia in elderly patients with gastric cancer: a retrospective cohort study
Authors: Cho Haruhiko , Tsuchida Kazuhito , Iwasaki Kenichi , Maezawa Yukio
Published: March 2021

Background

Post-operative pneumonia is a major complication after general elective surgery in elderly patients and is often caused by aspiration associated with oesophageal reflux. The aim of this study was to identify the risk factors of post-operative pneumonia after gastrectomy in elderly patients with gastric cancer with two potential risk factors of ageing and oesophageal reflux.

Methods

We retrospectively examined the data of 251 patients ≥75 years old who underwent gastrectomy between January 2014 and December 2018 in our institution. The reconstruction methods were Billroth-I or Roux-Y after distal gastrectomy, jejunal interposition or double tract after proximal gastrectomy and Roux-Y after total gastrectomy. The severity of pneumonia was evaluated by the Clavien–Dindo classification.

Results

Post-operative pneumonia was identified in 15 patients (5.9%) and was significantly associated with an age ≥80 years old, poor performance status, history of smoking and cardia-non-preserving gastrectomy (total gastrectomy and proximal gastrectomy) in univariate analyses. Multivariate analyses showed that a poor performance status and cardia-non-preserving gastrectomy were independent risk factors for post-operative pneumonia. The patients who suffered post-operative pneumonia required a longer hospital stay than those without post-operative pneumonia (P = 0.002).

Conclusion

We identified a poor performance status and cardia-non-preserving gastrectomy, which are likely to lead to oesophageal reflux, as risk factors for post-operative pneumonia in elderly patients with gastric cancer. These results warrant further prospective studies to evaluate their utility for reducing the rate of post-operative pneumonia in elderly patients through cardia-preserving gastrectomy or anti-reflux reconstruction.
Evolution of State Aid Rules
Authors: Kreuschitz Viktor , Nehl Hanns Peter
Published: March 2021

This chapter looks at the evolution of the legal framework for State aid during the past six decades of economic integration and addresses State aid rules in the context of balancing national policy objectives with the necessity to review aids at a supranational level. A dual trend emerges from the evolution of State aid rules over the last sixty years. On the one hand, the Court of Justice has played a key role in establishing new principles and designing rules governing State aid. In parallel, the Commission also acts as a rule-maker, by introducing relevant soft law and regulatory texts. In this context, the adoption of the Procedural Regulation in 1999 can be regarded as a turning point in the codification and development of State aid rules. The development of State aid is, however, not completed, as reflected in the last reforms of the State Aid Action Plan and the State Aid Modernization initiative.
The Legal Framework to Subsidies and State Aid Review
Authors: Kreuschitz Viktor , Nehl Hanns Peter
Published: March 2021

This chapter assesses the legal framework of the multi-level system of State aid and subsidies control not only on the level of the EU but also on the international level—the World Trade Organization (WTO)—and the national level by EU Member States. The control of subsidies and State aids as a multi-level phenomenon has been a laboratory of design solutions for procedural law provisions, enforcement techniques, and the development of general principles of law. It is one of the fields of law which has been most influential for the development of modern public law as a multi-level legal system with several constitutionalized levels. Not only by the sheer force of numbers and issues raised, State aid and subsidies cases have had a great influence on the development of procedural rights such as defence rights. It also added to the clarification of notions of discretion, the protection of legitimate interests, and principles of equality.
De Jure Compatible Aid under Article 107(2) TFEU
Authors: Kreuschitz Viktor , Nehl Hanns Peter
Published: March 2021

This chapter assesses the de jure compatible aid under Article 107(2) TFEU. As is well known, Article 107(1) TFEU introduces a general prohibition on granting State aid in the EU legal order. Nevertheless, this prohibition is not absolute because the same article permits derogations provided for in the TFEU. Article 107(2) provides for these de jure derogations, that is to say State aid which is compatible with the Treaty. According to this provision, three categories of State aid accord with the internal market, namely: (a) aid of a social character granted to individual consumers, provided that such aid is granted without discrimination related to the origin of the product concerned; (b) aid to make good the damage caused by natural disasters or exceptional occurrences; and (c) aid granted to certain areas of Germany affected by the division of that country.
Transport Aid
Authors: Kreuschitz Viktor , Nehl Hanns Peter
Published: March 2021

This chapter focuses on transport aid. Transport has, in many regards, always had a special place in EU law. In this diverse sector, the Union's powers are constrained and wide-ranging at the same time. On the one hand, the freedom to provide services only applies to transport if the Union legislators have adopted secondary legislation on market opening. On the other hand, the Court has emphasized on several occasions that the Treaty chapter on transport, Title VI, confers wide-ranging competences on the Union, enabling it to develop a common transport policy. Within this, the Union's powers with regards to State aid have steadily been growing in significance. The transport sector is not only ‘special’ when it comes to its place within EU law and State aid law in general, but also with regards to its place in services of general economic interest.
The Different Stages in the State Aid Procedure
Authors: Kreuschitz Viktor , Nehl Hanns Peter
Published: March 2021

This chapter discusses the different stages in the State aid procedure. Regulation 2015/1589 distinguishes mainly between two categories of aid: those that have been duly notified and those that are considered as ‘unlawful State aid’ because they have not been notified to the Commission prior to implementation. The Procedural Regulation 2015/1589 is firmly based on two related concepts: (i) loyal cooperation between the Member States and the Commission; and (ii) the conduct of the administrative procedures as a form of privileged dialogue between these two parties. In so far as the Member State cooperates loyally, by notifying a planned measure together with all the relevant information such as to allow the Commission to reach a preliminary decision on the measure, the Regulation provides at least for the Member State concerned a clear framework for the investigation in its first phase.
Vertical Agreements in EU Competition Law
Authors: Tuytschaever Filip , Wijckmans Frank
Published: March 2021

The book discusses the EU competition law regime and practice in respect of vertical agreements. The concept of vertical agreements is not limited to distribution arrangements, but covers also supply and subcontracting scenarios. Particular attention is paid to e-commerce and the sector-specific rules applicable to the automotive industry (Regulation 461/2010). The book covers systematically the various aspects of Regulation 330/2010, which is the European block exemption regulation generally applicable to vertical agreements, as well as the Vertical Guidelines related thereto. In addition to a systematic presentation of the relevant legal concepts, the book provides practical guidance and concrete cases. Such cases include European precedents and decisions adopted in national competition law proceedings. The authors have inserted concrete examples stemming from their private practice in the field. The book offers concrete guidance for vertical agreements falling outside of the scope of Regulation 330/2010 where the parties may need to conduct a so-called self-assessment. It describes the economic theories underpinning such assessment and presents the relevant economic concepts in a digestible manner. The book is intended as an easy reference tool for private practitioners and legal scholars. The second edition of the book has been labelled by many practitioners as their ‘bible’ on vertical agreements.
Motor Vehicle Distribution
Authors: Wijckmans Frank , Tuytschaever Filip
Published: March 2021

This chapter addresses the specific block exemption regime that applies to the automotive industry. The relevant regime is contained in Regulation 461/2010. Different from past practice, Regulation 461/2010 closely resembles the general block exemption (Regulation 330/2010) and limits itself to adding certain hardcore restrictions applicable in the secondary markets. The chapter provides an overview of the impact of the block exemption from the perspective of the various stakeholders active in the sector. It then goes on to describe separately the block exemption principles governing the distribution of motor vehicles, the provision of after-sales services, and the distribution of spare parts.
France
Authors: Chagny Muriel
Published: March 2021

This chapter examines how the Antitrust Damages Directive has been transposed in France. It begins with an overview of the transposition procedure, focusing on the French private enforcement context from the Ordinance of 1 December 1986—the ‘Magna Carta’ of French competition law—to Law no. 2008-776 of 4 August 2008 and the Consumer Law Act of 17 March 2014 (Hamon Law). It then discusses the scope of the transposition measure, noting that the French government went beyond the Directive and instituted a single regime for damages actions, before analysing specific issues that arose during the transposition, including those relating to the concept of an undertaking, the binding effect of competition authorities' decisions, the presumption of harm, the passing-on of overcharges, types of harm and assessment of damages, joint and several liability and the recovery of contributions from co-infringers, consensual dispute resolution, time-barring deadlines, access to evidence, and class actions.
Italy
Authors: Lopopolo Susanna
Published: March 2021

This chapter focuses on the transposition of the Antitrust Damages Directive in Italy. It first considers the transposition procedure, with emphasis on the Italian competition law system and more specifically public enforcement of antitrust law under the Autorità Garante per la concorrenza ed il mercato (AGCM), before discussing the issue of the ‘topographic’ location of the implementing regulation within the current legal system. It then examines the substantive and temporal scope of Italy’s transposition measure, known as Legge Delega, as well as specific issues that arose during the transposition, including those relating to disclosure of evidence, penalties, the binding force of National Competition Authority (NCA) decisions and judicial review, time limitation rules, joint and several liability, parent company liability, the passing-on of overcharges, the use of AGCM expertise in quantifying damages, consensual resolution of disputes, collective redress, and the concentration of jurisdiction.
Luxembourg
Authors: Cauffman Caroline
Published: March 2021

This chapter discusses the transposition of the Antitrust Damages Directive in Luxembourg. It first provides a general overview of the transposition procedure, focusing on the Transposition Act that was adopted by first vote in the plenary session of the Chambre des députés of 15 November 2016 and entered into force on 11 December 2016. It then considers the substantive and temporal scope of Luxembourg’s Transposition Act before concluding with an analysis of specific issues that arose during the transposition, including those relating to certain articles of the Directive that have not been specifically transposed, the protection of confidential information, principles of joint and several liability, the probative value of decisions of National Competition Authorities of other Member States, the presumption and quantification of harm by cartels, time-barring deadlines, sanctions, actions for damages by claimants from different levels in the supply chain, consensual dispute resolution, and parent company liability.
Transposition Context, Processes, Measures, and Scope
Authors: Rodger Barry , Ferro Miguel Sousa , Marcos Francisco
Published: March 2021

This chapter discusses the context, processes, measures, and scope of transposition of the Antitrust Damages Directive across 16 Member States. It first provides a general overview of the competition litigation context in MS, including Cyprus, France, Greece, Hungary, Italy, Spain, and the Netherlands, before considering the timescale for the Directive’s implementation. It then examines other particular aspects of the national processes involved in the adoption of the Directive transposition measures, including the authorities responsible for overseeing the implementation, as well as the form, level, and extent of consultation undertaken with interested parties and stakeholders. The chapter also analyses the nature of the transposition measures adopted across the Member States, key aspects of the debates and issues surrounding the substantive and temporal scope of the Directive’s application, and the difficulties that might arise in the interpretation of transposition measures by the national courts.
Concluding Remarks
Authors: Rodger Barry , Ferro Miguel Sousa , Marcos Francisco
Published: March 2021

This chapter reflects on how the book has examined the implementation of the EU's Antitrust Damages Directive across a selected number of key Member States and how its transposition has impacted on one particular aspect of the EU competition law enforcement framework: private enforcement through competition damages claims. It has discussed the national transposition processes, debates, and final measures introduced and implemented, and how best to incorporate the Directive within the pre-existing national legal provision, as well as considering some of the key problems in implementing the Directive. A number of unresolved and complicated issues have been identified, such as those relating to the practical application of the rules on the presumption of harm, passing-on and quantification of damages, how to determine liability within groups of companies, how to apportion joint and several liability between co-infringers, and consumer/collective redress in the competition law context.