bluuebunny/crossref_metadata_2025_split huggingface dataset:
Scalarized Einstein–Maxwell-scalar black holes in anti-de Sitter spacetime
Authors: Guo Guangzhou , Wang Peng , Wu Houwen , Yang Haitang 
Published: October 2021

AbstractIn this paper, we study spontaneous scalarization of asymptotically anti-de Sitter charged black holes in an Einstein–Maxwell-scalar model with a non-minimal coupling between the scalar and Maxwell fields. In this model, Reissner–Nordström-AdS (RNAdS) black holes are scalar-free black hole solutions, and may induce scalarized black holes due to the presence of a tachyonic instability of the scalar field near the event horizon. For RNAdS and scalarized black hole solutions, we investigate the domain of existence, perturbative stability against spherical perturbations and phase structure. In a micro-canonical ensemble, scalarized solutions are always thermodynamically preferred over RNAdS black holes. However, the system has much richer phase structure and phase transitions in a canonical ensemble. In particular, we report a RNAdS BH/scalarized BH/RNAdS BH reentrant phase transition, which is composed of a zeroth-order phase transition and a second-order one.
Covariant density and velocity perturbations of the quasi-Newtonian cosmological model in f(T) gravity
Authors: Sami Heba , Sahlu Shambel , Abebe Amare , Dunsby Peter K. S. 
Published: October 2021

AbstractWe investigate classes of shear-free cosmological dust models with irrotational fluid flows within the framework off(T) gravity. In particular, we use the$$1 + 3$$1+3covariant formalism and present the covariant linearised evolution and constraint equations describing such models. We then derive the integrability conditions describing a consistent evolution of the linearised field equations of thesequasi-Newtonianuniverses in thef(T) gravitational theory. Finally, we derive the evolution equations for the density and velocity perturbations of the quasi-Newtonian universe. We explore the behaviour of the matter density contrast for two models –$$f(T)= \mu T_{0}(T/T_{0})^{n}$$f(T)=μT0(T/T0)nand the more generalised case, where$$f(T)= T+ \mu T_{0} (T/T_{0})^{n}$$f(T)=T+μT0(T/T0)n, with and without the application of the quasi-static approximation. Our numerical solutions show that thesef(T) theories can be suitable alternatives to study the background dynamics, whereas the growth of energy density fluctuations change dramatically from the expected$$\Lambda $$ΛCDM behaviour even for small deviation from the general relativistic limits of the underlyingf(T) theory. Moreover, applying the so-called quasi-static approximation yields exact-solution results that are orders of magnitude different from the numerically integrated solutions of the full system, suggesting that these approximations are not applicable here.
Thermodynamics of graviton condensate
Authors: Alfaro Jorge , Mancilla Robinson 
Published: October 2021

AbstractIn this work, we present the thermodynamic study of a model that considers the black hole as a condensate of gravitons. In this model, the spacetime is not asymptotically flat because of a topological defect that introduces an angle deficit in the spacetime like in Global Monopole solutions. We have obtained a correction to the Hawking temperature plus a negative pressure associated with the black hole of mass M. In this way, the graviton condensate, which is assumed to be at the critical point defined by the condition $$\mu _{ch}=0,$$

μ

ch

=
0
,

has well-defined thermodynamic quantities P, V, $$T_{h}$$

T
h

, S, and U as any other Bose–Einstein condensate (BEC). In addition, we present a formal equivalence between the Letelier spacetime and the line element that describes the graviton condensate. We also discuss the Kiselev black hole, which can parametrize the most well-known spherically symmetric black holes. Finally, we present a new metric, which we will call the BEC–Kiselev solution, that allows us to extend the graviton condensate to the case of solutions with different matter contents.
Probing the parameters of a Schwarzschild black hole surrounded by quintessence and cloud of strings through four standard astrophysical tests
Authors: Cárdenas Víctor H. , Fathi Mohsen , Olivares Marco , Villanueva J. R. 
Published: October 2021

AbstractIn this paper, we concern about applying general relativistic tests on the spacetime produced by a static black hole associated with cloud of strings, in a universe filled with quintessence. The four tests we apply are precession of the perihelion in the planetary orbits, gravitational redshift, deflection of light, and the Shapiro time delay. Through this process, we constrain the spacetime’s parameters in the context of the observational data, which results in about $$\sim 10^{-9}$$

∼

10

-
9

for the cloud of strings parameter, and $$\sim 10^{-20}$$

∼

10

-
20

m$$^{-1}$$

-
1

for that of quintessence. The response of the black hole to the gravitational perturbations is also discussed.
Rotating spacetimes generalizing Lifshitz black holes
Authors: Herrera-Aguilar Alfredo , Herrera-Mendoza Jhony A. , Higuita-Borja Daniel F. 
Published: October 2021

AbstractWe present a spinning black hole solution in d dimensions with a maximal number of rotation parameters in the context of the Einstein–Maxwell-Dilaton theory. An interesting feature of such a solution is that it accommodates Lifshitz black holes when the rotation parameters are set to zero. We verify the rotating nature of the black hole solution by performing the quasi-local analysis of conserved charges and defining the corresponding angular momenta. In addition, we perform the thermodynamical analysis of the black hole configuration, show that the first law of thermodynamics is completely consistent, and obtain a Smarr-like formula. We further study the thermodynamic stability of the constructed solution from a local viewpoint, by computing the associated specific heats, and from a global perspective, by using the so-called new thermodynamic geometry. We finally make some comments related to a pathology found in the causal structure of the obtained rotating black hole spacetime and compute some of its curvature invariants.
NONLINEAR DYNAMIC CHARACTERISTICS AND OPTIMAL DESIGN OF VENTILATOR PIPELINE POLYMER COMPOSITE DAMPER UNDER RANDOM EXCITATION
Authors: LIU MINGLIANG , XU JIA , ZHU ZHIWEN 
Published: October 2021

For severe patients with new coronavirus pneumonia, the use and stability of the ventilator are important. In this paper, we proposed a new type of shock-absorbing structure that can be used to improve the stability of the ventilator’s gas pipeline, thereby reducing the risk of the gas pipeline falling due to external interference. The film shape memory alloy (SMA) compared with bulk SMA is more suitable for gas pipeline shock absorption due to its large volume ratio and extremely high energy density. In order to optimize the performance of actuator and enhance the utilization rate of SMA, the nonlinear characteristics of Ti-Ni thin film actuator are researched and the effect of SMA film position on the system are investigated. The van der Pol term is introduced to fit the hysteresis loop of shape memory materials. Thus, the nonlinear dynamic response of SMA thin film actuator under stochastic excitation is studied. The numerical and experiment results show that the position of SMA can change the system’s stability, the proposed structure can reduce the system’s vibration to the maximum extent. The results indicate that the new proposed polymer/SMA composite film micro-actuator exhibits high energy dissipation ability, and the utilization rate of smart material is enhanced. Therefore, the new damping structure proposed in this paper is of great significance to the damping of gas pipelines.
Multiple Environmental Influences on the Lightning of Cold-Based Continental Convection. Part II: Sensitivity Tests for Its Charge Structure and Land–Ocean Contrast
Authors: Phillips Vaughan T. J. , Patade Sachin 
Published: October 2021

Abstract
In Part I, an electrification scheme was described and a simulation of an observed cold-based storm from the U.S. Great Plains was validated with electrical observations. Most charge in the storm was separated by rebounding collisions of secondary ice originating from prior graupel–snow collisions. In this Part II, sensitivity tests are performed with the control simulation (Part I) and influences from environmental factors (aerosols, temperature, moisture, and shear) on lightning are elucidated. Environmental factors [e.g., convective available potential energy (CAPE)] controlling updraft speed are salient. When ascent is reduced by 30% and 70%, flashes become 70% fewer and disappear, respectively; faster ascent promotes positive cloud-to-ground (+CGs) flashes. Since cloud base is too cold (1°C) for coalescence, cloud condensation nucleus aerosol concentrations do not influence the lightning appreciably. The electrical response to varying concentrations of active ice nuclei is limited by most ice particles being secondary and less sensitive—a natural “buffer.” Imposing a maritime sounding suggests that the land–sea contrast in lightning for such storms is due to the vertical structure of environmental temperature and humidity. Weak CAPE, and both entrainment and condensate weight from a low cloud base, suppress ascent and charging. Maritime thermodynamic conditions reduce simulated flash rates by two orders of magnitude. Reducing aerosol loadings from continental to maritime only slightly reinforces this suppression. Last, a conceptual model is provided for how any simulated storm is either normal because graupel/hail is mostly positively charged or else is inverted/anomalous because graupel/hail is mostly negatively charged, with environmental factors controlling the charging. Impacts from microphysical processes, including three processes of secondary ice production, on lightning are analyzed.
Transient Eddy Kinetic Energetics on Mars in Three Reanalysis Datasets
Authors: Battalio J. Michael 
Published: October 2021

AbstractThe ability of Martian reanalysis datasets to represent the growth and decay of short-period (1.5 <P< 8 sol) transient eddies is compared across the Mars Analysis Correction Data Assimilation (MACDA), Open access to Mars Assimilated Remote Soundings (OpenMARS), and Ensemble Mars Atmosphere Reanalysis System (EMARS). Short-period eddies are predominantly surface based, have the largest amplitudes in the Northern Hemisphere, and are found, in order of decreasing eddy kinetic energy amplitude, in Utopia, Acidalia, and Arcadia Planitae in the Northern Hemisphere, and south of the Tharsis Plateau and between Argyre and Hellas basins in the Southern Hemisphere. Short-period eddies grow on the upstream (western) sides of basins via baroclinic energy conversion and by extracting energy from the mean flow and long-period (P> 8 sol) eddies when interacting with high relief. Overall, the combined impact of barotropic energy conversion is a net loss of eddy kinetic energy, which rectifies previous conflicting results. When Thermal Emission Spectrometer observations are assimilated (Mars years 24–27), all three reanalyses agree on eddy amplitude and timing, but during the Mars Climate Sounder (MCS) observational era (Mars years 28–33), eddies are less constrained. The EMARS ensemble member has considerably higher eddy generation than the ensemble mean, and bulk eddy amplitudes in the deterministic OpenMARS reanalysis agree with the EMARS ensemble rather than the EMARS member. Thus, analysis of individual eddies during the MCS era should only be performed when eddy amplitudes are large and when there is agreement across reanalyses.Significance StatementDust storms on Mars are initiated by traveling atmospheric waves, so understanding the relationships between waves and dust is critical to surface spacecraft safety. The growth and decay of waves are compared in three datasets to evaluate whether waves behave consistently across datasets and are represented similarly across different eras of instrumentation. Waves grow by instabilities caused by horizontal and vertical temperature gradients and lose energy to slower-traveling waves at higher altitudes, but agreement across datasets declines using more recent observations because of problems measuring temperatures near the surface. Regardless, combining dust storm observations and descriptions of traveling waves provides a new avenue for explaining dust storm variability on Mars.
Multiscale Aspects of the 26–27 April 2011 Tornado Outbreak. Part I: Outbreak Chronology and Environmental Evolution
Authors: Chasteen Manda B. , Koch Steven E. 
Published: October 2021

Abstract
One of the most prolific tornado outbreaks ever documented occurred on 26–27 April 2011 and comprised three successive episodes of tornadic convection that primarily impacted the southeastern United States, including two quasi-linear convective systems (hereinafter QLCS1 and QLCS2) that preceded the notorious outbreak of long-track, violent tornadoes spawned by numerous supercells on the afternoon of 27 April. The ∼36-h period encompassing these three episodes was part of a longer multiday outbreak that occurred ahead of a slowly moving upper-level trough over the Rocky Mountains. Here in Part I, we detail how the environment evolved to support this extended outbreak, with particular attention given to the three successive systems that each exhibited a different morphology and severity. The amplifying upper-level trough and attendant jet streak resulted from a Rossby wave–breaking event that yielded a complex tropopause structure and supported three prominent shortwave troughs that sequentially moved into the south-central United States. QLCS1 formed ahead of the second shortwave and was accompanied by rapid flow modifications, including considerable low-level jet (LLJ) intensification. The third shortwave moved into the lee of the Rockies early on 27 April to yield destabilization behind QLCS1 and support the formation of QLCS2, which was followed by further LLJ intensification and helped to establish favorable deep-layer shear profiles over the warm sector. The afternoon supercell outbreak commenced following the movement of this shortwave into the Mississippi Valley, which was attended by a deep tropopause fold, cold front aloft, and dryline that promoted two prominent bands of tornadic supercells over the Southeast.

Significance Statement
The tornado outbreak that impacted the United States on 26–27 April 2011 was part of an extended outbreak that produced 343 tornadoes and numerous fatalities. This paper is Part I of a study that describes the meteorological factors supporting such a prolific event. We focus on a 36-h period encompassing three convective episodes that impacted the Southeast and culminated in the widespread formation of long-track, violent tornadoes. Flow enhancements accompanying the first two episodes and the movement of a cold front aloft into the Southeast were found to contribute to the evolution of the final and most devastating episode. Part II describes how the first two episodes directly modified the environment to enhance the severity of this outbreak.
Creativity in Scientific Research: Multidisciplinarity Fosters Depth of Ideas Among Scientists in Electronic “Brainwriting” Groups
Authors: Michinov Nicolas , Jeanson Sophie 
Published: October 2021

Objective The aim of this study was to examine the potential benefits of multidisciplinarity among agri-food researchers working in small groups to generate ideas to stimulate innovation in the context of a laboratory project. Background Research on the role of multidisciplinarity in scientific research teams remains limited, particularly regarding the generation of ideas to innovate in a real laboratory project, and on a task with a real challenge for innovation. Method Researchers and agri-food research staff were assigned to small groups of either multidisciplinary or unidisciplinary composition to produce ideas on a cross-cutting theme for an innovative laboratory project using an electronic “brainwriting” application. Results A greater depth in idea generation (number of ideas per category) was observed in the multidisciplinary condition than in the unidisciplinary condition. Conclusion The main benefits of this study were to experimentally examine the effects of multidisciplinarity in small scientific research groups on the production of ideas in a field study conducted on the premises of an agri-food laboratory. Application This study provides advice on how to promote innovative projects by stimulating ideation processes, which includes constructing small multidisciplinary groups and using an electronic “brainwriting” technique.
Accuracy in recognising happy facial expressions is associated with antidepressant response to a NOP receptor antagonist but not placebo treatment
Authors: Dawson Gerard R , Post Anke , Smart Trevor S , Browning Michael , Harmer Catherine J 
Published: October 2021

Background: Clinical trials with putative antidepressants can be difficult to execute as it can take up to 8 weeks before differences emerge between drug and placebo, and long expensive trials often fail. Implementation of early response biomarkers could aid this process significantly with potential to identify new treatments. Aims: In a secondary analysis, we examined the association of early effects on emotional processing with later clinical outcome following treatment with the novel NOP antagonist LY2940094 versus placebo. We hypothesised that early induction of positive bias would be associated with reduced severity of depression after 8 weeks of treatment. Methods: This was a multicentre, randomised, double-blind, parallel-group, fixed-dose, placebo-controlled, 8 week study to assess sensitivity of the facial emotional recognition task (FERT) to early changes in emotional bias induced by LY2940094. Patients who met diagnostic criteria for major depression were randomised to receive LY2940094 ( N = 70) or placebo ( N = 66). At week 1 and 6, the FERT was completed by 33 patients in the LY2940094 group and 34 in the placebo group. Results: Patients identified happy faces with higher accuracy (Wald χ2(1,33) = 14.25, p < 0.001) after 1 week treatment with LY290094 compared to placebo (Wald χ2(1,32) = 0.83, p = 0.36) and this correlated with eventual treatment response measured by the Hamilton Depression Rating Scale 7 weeks later. Conclusion: These data suggest that emotional processing biomarkers may be sensitive to early effects of antidepressant treatment indicative of later clinical response. Further studies in this area may be useful in developing new treatments and clinical trial designs for predicting antidepressant response.
Risk factors for rebleeding in patients with obscure gastrointestinal bleeding from southern China
Authors: Liu Boying , Liu Sudong , Wen Pingwu , Wang Shengbing , Wang Fuqun , Gu Xiaodong 
Published: October 2021

Background To identify the risk factors associated with rebleeding in obscure gastrointestinal bleeding (OGIB) patients from southern China. Methods This retrospective study involved 229 patients who underwent small bowel endoscopy in our hospital between 1 January 2018 and 1 December 2020. The clinical characteristics and risk factors related to rebleeding were retrospectively evaluated. Results Rebleeding patients were significantly older than non-rebleeding patients (53.0 ± 15.9 vs. 46.2 ± 17.8 years), had lower hemoglobin concentrations (89.2 ± 28.1 vs. 126.2 ± 25.1 g/L), and higher blood urea nitrogen concentrations (5.4 ± 2.6 vs. 4.5 ± 2.2 µmol/L), respectively. A higher percentage of rebleeding patients had diabetes mellitus (13.9% vs. 2.9%) and overt bleeding (70.4% vs. 38.6%), and required blood transfusions (43.1% vs. 8.0%), compared with non-rebleeding patients, respectively. Multivariate logistic analysis indicated that drinking alcohol (odds ratio (OR): 9.27; 95% confidence interval (CI) = 1.35–63.78), anemia (OR: 17.38; 95% CI = 5.48–55.10), and blood transfusion (OR: 3.76; 95% CI = 1.04–13.56) increased the risk of rebleeding in OGIB patients. Conclusion Our data suggested that OGIB patients who drink alcohol, have anemia, and require blood transfusion have an increased risk of rebleeding.
Protective Influence of Breastfeeding on Cardiovascular Risk Factors in Women With Previous Gestational Diabetes Mellitus and Their Children: A Systematic Review and Meta-Analysis
Authors: Pathirana Maleesa M. , Ali Anna , Lassi Zohra S , Arstall Margaret A. , Roberts Claire T. , Andraweera Prabha H. 
Published: October 2021

Background: There is evidence that breastfeeding may provide protection against cardiovascular risk factors in mothers with a history of gestational diabetes mellitus and their children who were exposed in utero. Research Aim: To perform a systematic review and meta-analysis of observational studies to ascertain the effects of breastfeeding on cardiovascular risk factors in women with previous gestational diabetes mellitus and their children exposed in utero. Methods: Studies assessing conventional cardiovascular risk factors in women with previous gestational diabetes mellitus and children exposed in utero stratified by breastfeeding/no breastfeeding or breastfed/not breastfed were included. Gestational diabetes mellitus was defined based on the International Association of Diabetes in Pregnancy Study Group definition or previous accepted definitions. Breastfeeding was defined as reported in each study. Results: The literature search yielded 260 titles, of which 17 studies were selected to be in the review. Women with previous gestational diabetes mellitus who did not breastfeed had higher blood glucose ( SMD: 0.32, 95% CI [0.12, 0.53]) and a greater risk of developing Type 2 diabetes mellitus ( RR: 2.08 95% CI [1.44, 3.00]) compared to women with no history. There were not enough studies to conduct a meta-analysis on the effects of breastfeeding on risk factors for cardiovascular disease among children exposed to gestational diabetes mellitus in utero. Conclusion: Breastfeeding appears to be protective against cardiovascular risk factors among women who experience gestational diabetes mellitus.
Mining the Past: History Scripting Strategies and Competitive Advantage in a Family Business
Authors: Ge Bingbing , De Massis Alfredo , Kotlar Josip 
Published: October 2021

History is increasingly recognized as a distinctive source of competitive advantage for family businesses. Taking a rhetorical history perspective, we study how a family business leveraged the family’s three generations long history of entrepreneurship to sustain profitable growth over 16 years. Through our analysis, we identify three history scripting strategies—embedding, elaborating, and building family history—that created important sources of competitive advantage for the family business, facilitating acceptance by broader communities, building a reputation of continuity, and inspiring innovation through tradition. These findings advance the history-informed understanding of family firms’ idiosyncratic sources of superior performance.