bluuebunny/crossref_metadata_2025_split huggingface dataset:
Recent advances in regulating cholesterol and bile acid metabolism
Authors: Sato Ryuichiro 
Published: July 2020

Abstract
Cholesterol is an important component of lipids in animal membranes. All living cells can synthesize cholesterol, but the amount of synthesis is not sufficient, and therefore cholesterol synthesized in the liver is delivered to extrahepatic tissues as a form of LDL. The liver is a primary organ to not only synthesize but also catabolize cholesterol into bile acids, which ends up to excrete with the feces. The synthetic and catabolic pathways are precisely regulated under the negative-feedback control system under the transcriptional regulation driven by several transcription factors such as the sterol regulatory element-binding proteins (SREBPs), the liver x receptor, and the farnesoid x receptor. This review summarizes various findings including our recent discoveries in the molecular mechanism of activation of SREBP that is involved in the regulation of hepatic cholesterol biosynthesis, and a novel function of the metabolic end product of cholesterol, bile acids, in skeletal muscles.
Effective equation of state in modified gravity and observational constraints
Authors: Arora Simran , Meng Xin-he , Pacif S K J , Sahoo P K 
Published: July 2020

Abstract
In this article, the bulk viscosity is introduced in a modified gravity model. The gravitational action has a general f(R, T) form, where R and T are the curvature scalar and the trace of energy momentum tensor respectively. An effective equation of state (EoS) has been investigated in the cosmological evolution with bulk viscosity. In the present scenario, the Hubble parameter which has a scaling relation with the redshift can be obtained generically. The role of deceleration parameter q and EoS parameter ω is discussed to explain the late-time accelerating expansion of the Universe. The statefinder parameters and Om diagnostic analysis are discussed for our obtained model to distinguish from other dark energy models together with the analysis of energy conditions and velocity of sound for the model. We have also numerically investigated the model by detailed maximum likelihood analysis of 580 type Ia supernovae from Union 2.1 compilation datasets and updated 57 Hubble datasets (31 data points from differential age method and 26 points from BAO and other methods). It is with efforts found that the present model is in good agreement with observations.
Quantum geometry from higher gauge theory
Authors: Asante Seth K , Dittrich Bianca , Girelli Florian , Riello Aldo , Tsimiklis Panagiotis 
Published: July 2020

Abstract
Higher gauge theories play a prominent role in the construction of 4D topological invariants and have been long ago proposed as a tool for 4D quantum gravity. The Yetter lattice model and its continuum counterpart, the BFCG theory, generalize BF theory to 2-gauge groups and—when specialized to 4D and the Poincaré 2-group—they provide an exactly solvable topologically-flat version of 4D general relativity. The 2-Poincaré Yetter model was conjectured to be equivalent to a state sum model of quantum flat spacetime developed by Baratin and Freidel after work by Korepanov (KBF model). This conjecture was motivated by the origin of the KBF model in the theory of two-representations of the Poincaré 2-group. Its proof, however, has remained elusive due to the lack of a generalized Peter–Weyl theorem for 2-groups. In this work we prove this conjecture. Our proof avoids the Peter–Weyl theorem and rather leverages the geometrical content of the Yetter model. Key for the proof is the introduction of a kinematical boundary Hilbert space on which 1- and two-Lorentz invariance is imposed. Geometrically this allows the identification of (quantum) tetrad variables and of the associated (quantum) Levi-Civita connection. States in this Hilbert space are labelled by quantum numbers that match the two-group representation labels. Our results open exciting opportunities for the construction of new representations of quantum geometries. Compared to loop quantum gravity, the higher gauge theory framework provides a quantum representation of the ADM—Regge initial data, including an identification of the intrinsic and extrinsic curvature. Furthermore, it leads to a version of the diffeomorphism and Hamiltonian constraints that acts on the vertices of the discretization, thus providing a prospect for a quantum realization of the hypersurface deformation algebra in 4D.
Quantum field theory on global anti-de Sitter space-time with Robin boundary conditions
Authors: Morley Thomas , Taylor Peter , Winstanley Elizabeth 
Published: July 2020

Abstract
We compute the vacuum polarization for a massless, conformally coupled scalar field on the covering space of global, four-dimensional, anti-de Sitter space-time. Since anti-de Sitter space is not globally hyperbolic, boundary conditions must be applied to the scalar field. We consider general Robin (mixed) boundary conditions for which the classical evolution of the field is well-defined and stable. The vacuum expectation value of the square of the field is not constant unless either Dirichlet or Neumann boundary conditions are applied. We also compute the thermal expectation value of the square of the field. For Dirichlet boundary conditions, both thermal and vacuum expectation values approach the same well-known limit on the space-time boundary. For all other Robin boundary conditions (including Neumann boundary conditions), the vacuum and thermal expectation values have the same limit on the space-time boundary, but this limit does not equal that in the Dirichlet case.
Heavy ion induced single-event-transient effects in nanoscale ferroelectric vertical tunneling transistors by TCAD simulation
Authors: Tian Guoliang , Bi Jinshun , Xu Gaobo , Xi Kai , Yang Xueqin , Yin Huaxiang , Xu Qiuxia , Wang Wenwu 
Published: July 2020

Abstract
Tunnel field-effect transistors (TFETs) are strong candidates for ‘Internet of Things’ electronic devices, due to their ultra-low power consumption. In this work, we propose a novel nanoscale silicon-on-insulator double-gate ferroelectric tunneling ﬁeld-eﬀect transistor (SOI DG-FeTFET), and single-event-transient (SET) eﬀects are investigated by means of two-dimensional technology computer-aided design simulations. In addition, we perform systematic analysis and comparison with a silicon-on-insulator double-gate ferroelectric ﬁeld-eﬀect transistor (SOI DG-FeET) . The simulation results show that the peak value of the drain transient current achieved by our DG-FeTFET is up to 2.72 × 10–4 A at 10 MeV·cm2 mg−1, which is much higher than the on-state current (I
on) ∼ 7.63 × 10−5 A at V
d = 0.5 V. Moreover, our results show that the DG-FeTFET is more susceptible to SET eﬀects than FeFET. The results also show that the bipolar ampliﬁcation eﬀect can be neglected, and that the drift-diﬀusion mechanism is dominant in the carrier collection process in the DG-FeTFET. The transient responses of the single event eﬀect are also strongly correlated with the strike location of heavy ions, with the most sensitive part being close to the area where interband tunneling occurs and the electric ﬁeld is the strongest. These analyses may prove relevant for applications SOI DG-FeTFETs/FeFETs in environments where radiation is present.
Experimental evidence of intrabeam scattering in a free-electron laser driver
Authors: Di Mitri S , Perosa G , Brynes A , Setija I , Spampinati S , Williams P H , Wolski A , Allaria E , Brussaard S , Giannessi L , Penco G , Rebernik P R , Trovò M 
Published: July 2020

Abstract
The effect of multiple small-angle Coulomb scattering, or intrabeam scattering (IBS) is routinely observed in electron storage rings over the typical damping time scale of milliseconds. So far, IBS has not been observed in single pass electron accelerators because charge density orders of magnitude higher than in storage rings would be needed. We show that such density is now available at high brightness electron linacs for free-electron lasers (FELs). We report measurements of the beam energy spread in the FERMI linac in the presence of the microbunching instability, which are consistent with a revisited IBS model for single pass systems. We also show that neglecting the hereby demonstrated effect of IBS in the parameter range typical of seeded VUV and soft x-ray FELs, results in too conservative a facility design, or failure to realise the accessible potential performance. As an example, an optimization of the FERMI parameters driven by an experimentally benchmarked model, opens the door to the extension of stable single spectral line emission to the water window (2.3–4.4 nm), with far-reaching implications for experiments in a variety of disciplines, ranging from physics and chemistry to biology and material sciences, and including nonlinear x-ray optics based on the four-wave-mixing approach.
What are the best combinations of fuel-vehicle technologies to mitigate climate change and air pollution effects across the United States?
Authors: Tong Fan , Azevedo Inês M L 
Published: July 2020

Abstract
The transportation sector is the largest contributor to CO2 emissions and a major source of criteria air pollutants in the United States. The impact of climate change and that of air pollution differ in space and time, but spatially-explicit, systematic evaluations of the effectiveness of alternative fuels and advanced vehicle technologies in mitigating both climate change and air pollution are lacking. In this work, we estimate the life cycle monetized damages due to greenhouse gas emissions and criteria air pollutant emissions for different types of passenger-moving vehicles in the United States. We find substantial spatial variability in the monetized damages for all fuel-vehicle technologies studied. None of the fuel-vehicle technologies leads simultaneously to the lowest climate change damages and the lowest air pollution damages across all U.S. counties. Instead, the fuel-vehicle technology that best mitigates climate change in one region is different from that for the best air quality (i.e. the trade-off between decarbonization and air pollution mitigation). For example, for the state of Pennsylvania, battery-electric cars lead to the lowest population-weighted-average climate change damages (a climate change damage of 0.87 cent/mile and an air pollution damage of 1.71 cent/mile). In contrast, gasoline hybrid-electric cars lead to the lowest population-weighted-average air pollution damages (a climate change damage of 0.92 cent/mile and an air pollution damage of 0.77 cent/mile). Vehicle electrification has great potential to reduce climate change damages but may increase air pollution damages substantially in regions with high shares of coal-fired power plants compared to conventional vehicles. However, clean electricity grid could help battery electric vehicles to achieve low damages in both climate change and air pollution.
Are biodiversity losses valued differently when they are caused by human activities? A meta-analysis of the non-use valuation literature
Authors: Nobel Anne , Lizin Sebastien , Brouwer Roy , Bruns Stephan B , Stern David I , Malina Robert 
Published: July 2020

Abstract
Many countries committed to climate action by adopting the Paris Agreement and Sustainable Development Goals in 2015. This study synthesizes 40 years of scientific evidence of what may be an important benefit of these commitments: the non-use value of biodiversity conservation. The synthesis investigates whether biodiversity values can be integrated into climate change damage estimates based on non-use valuation studies of different threats to biodiversity. In the absence of estimates of public willingness to pay (WTP) to avoid the adverse impacts of anthropogenic climate change on biodiversity, we synthesize non-use values for biodiversity conservation from stated preference studies that account for a heterogeneous set of biodiversity threats. We test whether biodiversity non-use values are affected by the threats that policies aim to address, be it human activities or other threats. We estimate meta-regression models in which we explain the variation in these non-use values by accounting for the observed heterogeneity in good, methodology, sample, and context characteristics. We estimate meta-regression models using 159 observations from 62 publications. The models suggest that non-use values for biodiversity conservation addressing human impacts may be larger than those addressing other threats. We also find that non-use values are generally not sensitive to which biodiversity indicators, habitat types, or taxonomic groups are valued. We predict that the mean annual WTP for avoiding human-caused biodiversity losses ranges from 0.2 to 0.4% of GDP per capita. Our findings suggest that state-of-the-art climate change damage functions in integrated assessment models may underestimate actual damage costs because they do not incorporate the premium that the public is willing to pay to avoid human-caused biodiversity losses.
Climate and growing season variability impacted the intensity and distribution of Fremont maize farmers during and after the Medieval Climate Anomaly based on a statistically downscaled climate model
Authors: Thomson Marcus J , MacDonald Glen M 
Published: July 2020

AbstractThe rise and decline of many complex, pre-European maize-farming cultures in the American Southwest coincides with the warm, climatically quiescent Medieval Climate Anomaly (MCA, ca. 850–1350 CE) and transition to the cool, hydrologically variable Little Ice Age (LIA, ca. 1350–1850 CE). The effects of drought on early subsistence agriculture in the Southwest is well studied, but the impact of temperature stress and variability on the growth of maize crops and which areas were most resilient to such stress remain open questions. We statistically downscaled outputs from a paleo-climate model experiment (CESM1 LME) to map changes to cumulative growing degree days for maize (GDD, 30/10 °C) and precipitation over Utah between 850 and 1449 CE, and downscaled GDD changes to local Fremont Culture archaeological site occupations from radiocarbon-dated contexts mapped as spatially discrete kernel density estimates of summed probability distributions (SPDs). We then analyzed correspondences between Fremont SPDs and GDD/precipitation between 850 and 1449 CE. In general, we found (1) high Fremont occupation intensity coincident with GDD that is less volatile than the long term average, and low occupation intensity coincident with, or following, periods of volatile GDD; (2) intensified occupation of high-elevation sites during the MCA, followed by a retreat to lower elevation sites coincident with a sudden rise in annual temperature volatility and increasing drought conditions; and (3) these occupation changes occurred in spite of the greater temperatures and variability in GDD at low-elevation sites. We found evidence that increased inter-annual variability of growing seasons prior to the onset of the LIA, was likely a determinant of Fremont subsistence strategy decision making, and high-elevation site occupation. The most resilient Fremont occupations in the face of these challenges were sited where growing season lengths were least variable.
Hydrology is the key factor for nitrogen export from tile-drained catchments under consistent land-management
Authors: Bauwe Andreas , Kahle Petra , Tiemeyer Bärbel , Lennartz Bernd 
Published: July 2020

Abstract
In this study, 14 years of climate, stream flow, land management, nitrate-nitrogen (NO3
–N) load and concentration data were analyzed to identify potential drivers for NO3
–N losses at two tile-drained catchments under cropland use in northeastern Germany. Mean (±standard deviation) annual NO3
–N concentrations were 9.7 ± 2.9 (drainage plot) and 6.8 ± 2.4 mg l−1 (ditch catchment), while mean annual NO3
–N loads amounted to 22 ± 16 and 20 ± 16 kg ha−1, respectively. Significant positive relationships between annual discharge and annual NO3
–N losses underlined the importance of hydrologic conditions on NO3
–N export mechanisms. No direct relationships were found between N soil surface surpluses and NO3
–N losses. Any possible impact of N soil surface surpluses on NO3
–N export rates was overridden by the hydro-meteorological conditions in the catchment. Positive correlations between the climatic water balance and NO3
–N losses suggest that agricultural catchments with similar characteristics as ours may face—without countermeasures—increased N losses in the future as regional climate projections predict wetter winters in the coming decades. Our analysis has further shown that effects of land management strategies aiming at reducing N losses into surface waters might only become visible with a delay of years or even decades.
Predicting Sediment transport in sewers using integrative harmony search-ANN model and factor analysis
Authors: Zounemat-Kermani Mohammad , Fadaee Marzieh , Adarsh S , Hinkelmann Reinhard 
Published: July 2020

Abstract
This study evaluates the performance of an integrated version of artificial neural network namely HS-ANN (which is a combination of neural network and heuristic harmony search algorithm) as an alternative approach to predict the sediment transport in terms of sediment volumetric concentration (Cv) in sewer pipe systems. To overcome the complexities of choosing the optimum number of the input variables and to consider the effective parameters of the model, the factor analysis technique is utilized. In addition to the HS-ANN model, an empirical equation, as well as a multiple linear regression model, are also considered. The mean square error (RMSE), mean absolute percentage error (MAPE), and Pearson correlation coefficients (PCC) are used for evaluating the accuracy of the applied models. As the comparisons demonstrate, the HS-ANN model (PCC = 0.97) is more accurate than the existing empirical equation and MLR model and could be successfully employed in predicting sediment transport in sewer networks.
Excess Soluble fms-like Tyrosine Kinase 1 Correlates With Endothelial Dysfunction and Organ Failure in Critically Ill Coronavirus Disease 2019 Patients
Authors: Dupont Vincent , Kanagaratnam Lukshe , Goury Antoine , Poitevin Gaël , Bard Mathieu , Julien Gauthier , Bonnivard Michel , Champenois Vanessa , Noel Violaine , Mourvillier Bruno , Nguyen Philippe 
Published: July 2020

Abstract
Excess soluble fms-like tyrosine kinase 1 (sFlt-1), a soluble inhibitor of vascular endothelial growth factor pathway, has been demonstrated to promote endothelial dysfunction. Here, we demonstrate that sFlt-1 plasma levels correlate with respiratory symptom severity, expression of endothelial dysfunction biomarker, and incidence of organ failure in coronavirus disease 2019 patients.
Clinical Trials Registration: NCT04394195.
Implications of Efavirenz Pharmacogenetics When Switching From Efavirenz- to Dolutegravir-containing Antiretroviral Regimens
Authors: Haas David W , Acosta Edward P 
Published: July 2020

Abstract
Many patients switch from efavirenz- to dolutegravir-based regimens. In a phase 1 dolutegravir-efavirenz interaction study, mean dolutegravir minimum concentration decreased by 60% and 85% among CYP2B6 normal and slow/intermediate metabolizers, respectively. Mean efavirenz half-life was 2.7 times greater in slow vs normal metabolizers. Slow metabolizers will experience more prolonged subtherapeutic dolutegravir concentrations.
Severe Acute Respiratory Syndrome Coronavirus 2 Infects and Damages the Mature and Immature Olfactory Sensory Neurons of Hamsters
Authors: Zhang Anna Jinxia , Lee Andrew Chak-Yiu , Chu Hin , Chan Jasper Fuk-Woo , Fan Zhimeng , Li Can , Liu Feifei , Chen Yanxia , Yuan Shuofeng , Poon Vincent Kwok-Man , Chan Chris Chung-Sing , Cai Jian-Piao , Wu Kenneth Lap-Kei , Sridhar Siddharth , Chan Ying-Shing , Yuen Kwok-Yung 
Published: July 2020

Abstract

Background
Coronavirus disease 2019 (COVID-19) is primarily an acute respiratory tract infection. Distinctively, a substantial proportion of COVID-19 patients develop olfactory dysfunction. Especially in young patients, loss of smell can be the first or only symptom. The roles of inflammatory obstruction of the olfactory clefts, inflammatory cytokines affecting olfactory neuronal function, destruction of olfactory neurons or their supporting cells, and direct invasion of olfactory bulbs in causing olfactory dysfunction are uncertain.

Methods
We investigated the location for the pathogenesis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from the olfactory epithelium (OE) to the olfactory bulb in golden Syrian hamsters.

Results
After intranasal inoculation with SARS-CoV-2, inflammatory cell infiltration and proinflammatory cytokine/chemokine responses were detected in the nasal turbinate tissues. The responses peaked between 2 and 4 days postinfection, with the highest viral load detected at day 2 postinfection. In addition to the pseudo-columnar ciliated respiratory epithelial cells, SARS-CoV-2 viral antigens were also detected in the mature olfactory sensory neurons labeled by olfactory marker protein, in the less mature olfactory neurons labeled by neuron-specific class III β-tubulin at the more basal position, and in the sustentacular cells, resulting in apoptosis and severe destruction of the OE. During the entire course of infection, SARS-CoV-2 viral antigens were not detected in the olfactory bulb.

Conclusions
In addition to acute inflammation at the OE, infection of mature and immature olfactory neurons and the supporting sustentacular cells by SARS-CoV-2 may contribute to the unique olfactory dysfunction related to COVID-19, which is not reported with SARS-CoV-2.
Finite-element EM modelling on hexahedral grids with an FD solver as a pre-conditioner
Authors: Yavich Nikolay , Zhdanov Michael S 
Published: July 2020

SUMMARY
The finite-element (FE) method is one of the most powerful numerical techniques for modelling 3-D electromagnetic fields. At the same time, there still exists the problem of efficient and economical solution of the respective system of FE equations in the frequency domain. In this paper, we concentrate on modelling with adapted hexahedral or logically rectangular grids. These grids are easy to generate, yet they are flexible enough to incorporate real topography and seismic horizons. The goal of this work is to show how a finite-difference (FD) solver can be used as a pre-conditioner for hexahedral FE modelling. Applying the lowest order Nédélec elements, we present a novel pre-conditioned iterative solver for the arising system of linear equations that combines an FD solver and simple smoothing procedure. The particular FD solver that we use relies on the implicit factorization of the horizontally layered earth matrix. We assessed runtime and accuracy of the presented approach on synthetic and real resistivity models (topography of the Black Sea continental slope). We further compared performance of our program versus publicly available Mare2DEM, ModEM and MUMPS programs/libraries. Our examples involve plane-wave and controlled source modelling. The numerical examples demonstrate that the presented approach is fast and robust for models with moderate contrast, supports highly deformed cells, and is quite memory-economical.