bluuebunny/crossref_metadata_2025 huggingface dataset:
Lower troponin expression in the right ventricle of rats explains interventricular differences in E–C coupling
Authors: Jeon Young Keul , Kwon Jae Won , Jang Jihyun , Choi Seong Woo , Woo Joohan , Cho Su Han , Yu Byeong Il , Chun Yang Sook , Youm Jae Boum , Zhang Yin Hua , Kim Sung Joon
Published: January 2022

Despite distinctive functional and anatomic differences, a precise understanding of the cardiac interventricular differences in excitation–contraction (E–C) coupling mechanisms is still lacking. Here, we directly compared rat right and left cardiomyocytes (RVCM and LVCM). Whole-cell patch clamp, the IonOptix system, and fura-2 fluorimetry were used to measure electrical properties (action potential and ionic currents), single-cell contractility, and cytosolic Ca2+ ([Ca2+]i), respectively. Myofilament proteins were analyzed by immunoblotting. RVCM showed significantly shorter action potential duration (APD) and higher density of transient outward K+ current (Ito). However, the triggered [Ca2+]i change (Ca2+ transient) was not different, while the decay rate of the Ca2+ transient was slower in RVCM. Although the relaxation speed was also slower, the sarcomere shortening amplitude (ΔSL) was smaller in RVCM. SERCA activity was ∼60% lower in RVCM, which is partly responsible for the slower decay of the Ca2+ transient. Immunoblot analysis revealed lower expression of the cardiac troponin complex (cTn) in RVCM, implying a smaller Ca2+ buffering capacity (κS), which was proved by in situ analysis. The introduction of these new levels of cTn, Ito, and SERCA into a mathematical model of rat LVCM reproduced the similar Ca2+ transient, slower Ca2+ decay, shorter APD, and smaller ΔSL of RVCM. Taken together, these data show reduced expression of cTn proteins in the RVCM, which provides an explanation for the interventricular difference in the E–C coupling kinetics.
Unitarity, clock dependence and quantum recollapse in quantum cosmology
Authors: Gielen Steffen , Menéndez-Pidal Lucía
Published: January 2022

We continue our analysis of a quantum cosmology model describing a flat Friedmann–Lemaître–Robertson–Walker Universe filled with a (free) massless scalar field and an arbitrary perfect fluid. For positive energy density in the scalar and fluid, each classical solution has a singularity and expands to infinite volume. When quantising we view the cosmological dynamics in relational terms, using one degree of freedom as a clock for the others. Three natural candidates for this clock are the volume, a time variable conjugate to the perfect fluid, and the scalar field. We have previously shown that requiring unitary evolution in the ‘fluid’ time leads to a boundary condition at the singularity and generic singularity resolution, while in the volume time semiclassical states follow the classical singular trajectories. Here we analyse the third option of using the scalar field as a clock, finding further dramatic differences to the previous cases: the boundary condition arising from unitarity is now at infinity. Rather than singularity resolution, this theory features a quantum recollapse of the Universe at large volume, as was shown in a similar context by Pawłowski and Ashtekar. We illustrate the properties of the theory analytically and numerically, showing that the ways in which the different quantum theories do or do not depart from classical behaviour directly arise from demanding unitarity with respect to different clocks. We argue that using a Dirac quantisation would not resolve the issue. Our results further illustrate the problem of time in quantum gravity.
Effective cosmology from one-body operators in group field theory
Authors: Gielen Steffen , Marchetti Luca , Oriti Daniele , Polaczek Axel
Published: January 2022

We propose a new method for obtaining an effective Friedmann–Lemaître–Robertson–Walker (FLRW) cosmology from the quantum gravity dynamics of group field theory (GFT), based on the idea that an FLRW universe is characterised by a few macroscopic observables. Rather than relying on assuming a particular type of quantum state and computing expectation values in such a state, here we directly start from relations between macroscopic observables (defined as one-body operators) and formulate dynamics only for those observables. We apply the effective approach to constrained quantum systems (as developed by Bojowald and collaborators) to GFT, providing a systematic expansion in powers of ℏ. We obtain a kinematical phase space of expectation values and moments, which does not require an a priori choice of clock variable. We identify a gauge fixing of the system which corresponds to choosing one of the cosmological variables (with the role of extrinsic curvature) as a clock and which allows us to rewrite the effective dynamics in relational form. We show necessary and sufficient conditions for the resulting dynamics of expectation values to be compatible with those of classical FLRW cosmology and discuss the impact of quantum fluctuations.
Temperature dependent carrier transport in few-layered MoS2: from hopping to band transport
Authors: Cheng Junao , Poehler Scott , Laskar Masihhur , Ma Lu , Kannappan Santhakumar , Rajan Siddharth , Wu Yiying , Lu Wu
Published: January 2022

Understanding the carrier transport mechanisms is critical for electronic devices based on 2D semiconductors. Here, using a two-terminal device configuration, we show that the carrier transport behaviours in chemical vapour deposited few-layer MoS2 transition from resonant tunnelling to hopping, and eventually to band transport as the temperature increases from 5 K to 370 K. Specifically, the transport in the channel is dominated by resonant tunnelling when T < 30 K is reflected in the temperature-independent conductance. At 50 K < T < 110 K, the channel conductance exhibits a dependence of exp(T
1/2), a signature of Efros–Shklovskii type variable range hopping (VRH). At 110 K < T < 160 K, carrier transport behaves in a transition region with potential attribution to Mott-type VRH. At 160 K < T < 210 K, the nearest neighbour hopping mechanism is confirmed by the linear dependence from the resistance curve derivative analysis. For VRH, the localization length, hopping distance and energy, Coulomb gap energy and density of states are extracted. At T > 210 K, the carrier transport is dominated by thermally activated band transport based on AC conductance and mobility analysis. These findings are significant for revealing the material properties for future 2D semiconductor device applications.
Control of sensitivity in vortex-type magnetic tunnel junction magnetometer sensors by the pinned layer geometry
Authors: Endo Motoki , Al-Mahdawi Muftah , Oogane Mikihiko , Ando Yasuo
Published: January 2022

The tuning of sensitivity and dynamic range in linear magnetic sensors is required in various applications. We demonstrate the control and design of the sensitivity in magnetic tunnel junction (MTJ) sensors with a vortex-type sensing layer. In this work, we develop sensor MTJs with NiFe sensing layers having a vortex magnetic configuration. We demonstrate that by varying the pinned layer size, the sensitivity to magnetic field is tuned linearly. We obtain a high magnetoresistance ratio of 140%, and we demonstrate a controllable sensitivity from 0.85% Oe−1 to 4.43% Oe−1, while keeping the vortex layer fixed in size. We compare our experimental results with micromagnetic simulations. We find that the linear displacement of vortex core by an applied field makes the design of vortex sensors simple. The control of the pinned layer geometry is an effective method to increase the sensitivity, without affecting the vortex state of the sensing layer. Furthermore, we propose that the location of the pinned layer can be used to realize more sensing functionalities from a single sensor.
The effect of particle size and relative humidity on triboelectric charge saturation
Authors: Cruise Reuben D , Hadler Kathryn , Starr Stanley O , Cilliers Jan J
Published: January 2022

Triboelectric charging is present in numerous technologies and everyday processes, providing both problems and opportunities. Despite this, there is no generalised model for the amount of charge that will build up on surfaces in contact. Here, we develop a new model for the saturation charge on triboelectrically charged spherical insulators, accounting for both equalisation of surface potentials and electrical breakdown of the surrounding medium. Experiments are conducted under controlled temperature and humidity using two independent methods, measuring the saturation charge on polymer spheres contacting grounded stainless steel. The results verify our equalisation of surface potentials model which describes how saturation charge density increases for smaller particle sizes. Key triboelectric properties are calculated: The estimated saturation charge on a flat surface and the equalisation potential between different materials, which can be used to predict charge saturation and quantify a triboelectric series. The transition radius below which electrical breakdown will cause saturation of charge is also calculated theoretically. Limitations to the model are demonstrated experimentally. As particle size reduces, a point is reached at which the electrostatic adhesion of particles to the grounded charging surface prevents further charge build-up. Furthermore, it is found that the saturation charge for smaller particles in humid conditions is greatly reduced. These calculations, and the demonstrated procedure, can serve as a tool for the design of technologies and processes influenced by triboelectric charge build-up, including triboelectric nanogenerators and electrostatic mineral separators.
Janus 2H-VSSe monolayer: two-dimensional valleytronic semiconductor with nonvolatile valley polarization
Authors: Abdollahi Mahsa , Bagheri Tagani Meysam
Published: January 2022

Valleytronic as a hot topic in recent years focuses on electrons’ valley degree of freedom as a quantum information carrier. Here, by combining two-band k.p model with high-throughput density functional theory (DFT) calculations, the valley states of Janus 2H-VSSe monolayer are studied which have spontaneous polarization. Nonvolatile valley polarization state is mainly arises from intrinsic ferromagnetism contributed by V-3d electronic configuration and not the spontaneous out-of-plane dipole moment of VSSe monolayer. The effective Hamiltonian model and DFT calculations both showed that the valley splitting mainly originates from the smaller spin splitting coming from the spin–orbit coupling effect rather than the spin splitting of magnetic exchange field. By using the effective Dirac Hamiltonian and Kubo formula, we further calculated the longitudinal and transversal conductivities and absorption spectra of VSSe monolayer which exhibits an anomalous valley Hall effect and clear valley-selective circular dichroism. Our calculations indicate that the modification of valley and spin splitting related to Berry curvature by applying an external strain is more noticeable than by the change of the magnetic moment orientation and electric field. We found that carriers accumulation with particular spin and valley label can be manipulated by tuning effective Hamiltonian parameters. The coexistence of robust in-plane magnetic ordering and spontaneous valley polarization of 2H-VSSe monolayer supports the possibility of applications in spintronics, valleytronics and optoelectronics devices.
Multi-frequency sequential sparse Bayesian learning for DOA estimation of the moving wideband sound source
Authors: Chen Guo , Lu Yonggang
Published: January 2022

To obtain the direction of arrival (DOA) of the moving sound source from the sequential measurements collected by the microphone array is the main task in acoustic tracking and detection. Thanks to the development of compressive sensing and sparse Bayesian learning (SBL), treating time-varying DOA estimation as time-varying sparse signal recovery is considered to be a promising idea. However, most methods have assumed that the source is narrowband and the DOA is on the predefined sparse grid at each estimation step. In fact, most sound sources in the air are wideband and the DOA varies continuously. Therefore, the multi-frequency sequential SBL is proposed for the DOA estimation of the moving wideband sound source in this paper. In this method, gamma hyperprior is used as sparsity-promoting prior for multi-frequency bins so that the multi-frequency measurements can be utilized simultaneously, and with an inexact dynamic model, the sparsity-dependent information from the multi-frequency sequential measurements can be propagated to the next estimation step to improve the performance. Besides, the off-grid refinement is incorporated into the framework to adapt to the continuously varying DOA. Simulation results demonstrate that the proposed method has better performances under low signal-to-noise conditions with higher estimation accuracy and less computation time compared to other state-of-the-art methods. The field experiments show that our proposed method can has a stronger ability to suppress grating lobes and spatial aliasing than conventional methods in the estimation for wideband DOA and adapt to the scenarios where the number of sources also changes.
Implementation of the Marangoni effect in an open-source software environment and the influence of surface tension modeling in the mushy region in laser powder bed fusion (LPBF)
Authors: Wirth Florian , Tonn Teresa , Schöberl Markus , Hermann Stefan , Birkhofer Hannes , Ploshikhin Vasily
Published: January 2022

Tangential surface tension forces on a gas–liquid interface due to surface tension gradients have been implemented in the computational fluid dynamics (CFD) solver icoReactingMultiphaseInterFoam provided by the open-source software environment of OpenFOAM OpenCFD Ltd (ESI Group) OpenFOAM (online) https://www.openfoam.com/ (accessed 21 May 2021), so that the Marangoni effect can be taken into account, which is a main driver of heat transfer in additive manufacturing processes that comprise a melt pool. The solver surpasses the capabilities of similar open-source projects by considering a wide range of physical effects, e.g. multiple phases, melting, solidification, evaporation, and laser beam heat sources with an arbitrary intensity distribution and thus makes it an appealing framework, especially for the simulation of the laser powder bed fusion (LPBF) process. Herein, all relevant details and derivation considering the Marangoni effect are provided and validated by means of a benchmark problem by comparing the obtained results with the available analytical solution, with the results obtained from a commercial CFD tool and with the results of other authors. The modified solver is additionally validated by comparing the results from LPBF simulations with experimental data. Furthermore, the influence of the surface tension modeling on the mushy region is investigated. The optimized implementation shows improvements of the simulation results in both the dimensions and shape of the melt pool and the resulting surface with regard to the experimental data.
On the modified fractional Korteweg–de Vries and related equations
Authors: Klein Christian , Saut Jean-Claude , Wang Yuexun
Published: January 2022

We consider in this paper modified fractional Korteweg–de Vries and related equations (modified Burgers–Hilbert and Whitham). They have the advantage with respect to the usual fractional KdV equation to have a defocusing case with a different dynamics. We will distinguish the weakly dispersive case where the phase velocity is unbounded for low frequencies and tends to zero at infinity and the strongly dispersive case where the phase velocity vanishes at the origin and goes to infinity at infinity. In the former case, the nonlinear hyperbolic effects dominate for large data, leading to the possibility of shock formation though the dispersive effects manifest for small initial data where scattering is possible. In the latter case, finite time blow-up is possible in the focusing case but not the shock formation. In the defocusing case global existence and scattering is expected in the energy subcritical case, while finite time blow-up is expected in the energy supercritical case. We establish rigorously the existence of shocks with blow-up time and location being explicitly computed in the weakly dispersive case, while most of the results on the strongly dispersive case are derived via numerical simulations, for large solutions. Moreover, the shock formation result can be extended to the weakly dispersive equation with some generalized nonlinearity. We will also comment briefly on the BBM versions of those equations.
Embedding information onto a dynamical system
Authors: Manjunath G
Published: January 2022

The celebrated Takens’ embedding theorem concerns embedding an attractor of a dynamical system in a Euclidean space of appropriate dimension through a generic delay-observation map. The embedding also establishes a topological conjugacy. In this paper, we show how an arbitrary sequence can be mapped into another space as an attractive solution of a nonautonomous dynamical system. Such mapping also entails a topological conjugacy and an embedding between the sequence and the attractive solution spaces. This result is not a generalisation of Takens embedding theorem but helps us understand what exactly is required by discrete-time state space models widely used in applications to embed an external stimulus onto its solution space. Our results settle another basic problem concerning the perturbation of an autonomous dynamical system. We describe what exactly happens to the dynamics when exogenous noise perturbs continuously a local irreducible attracting set (such as a stable fixed point) of a discrete-time autonomous dynamical system.
Spectral Moran measures on

R2

*
Authors: Yan Zhi-Hui
Published: January 2022

In this paper, we consider the spectral properties of the Moran measure

μ

R
,
D

on

R

2

generated by the pair

(

R
,
D

)

, where

R
=

b

1

0

0

b

2

is an expanding real matrix, and

D
=

{

D

i

}

i
=
1

∞

⊆

Z

2

with

#

D

i

=
p

, where

sup

i
∈
N
,
d
∈

D

i

|
d
|
<
∞

, and p is a prime number. Let

B

(

p

)

:

≡

1

p

j

k

:
1
⩽
j
,
k
⩽
p
−
1

and

Z

(

δ

^

E

)

=

{

x
∈

R

2

:

δ

^

E

(

x

)

=
0

}

, where

δ

E

=

1

#
E

∑

e
∈
E

δ

e

, δ

e
denotes the Dirac measure at e. We show that under the conditions that

Z

(

δ

^

D

i

)

=

⋃

j
=
1

p
−
1

(

j

a

i

+

Z

2

)

for some

a

i

∈
B

(

p

)

, and

{

x
∈

0
,
1

2

:
|

δ

^

D

i

(

x

)

|
=
1

}

=

0

0

, then

μ

R
,
D

is a spectral measure if and only if

R
=

p

k

1

0

0

p

k

2

for some

k

1

,

k

2

∈
N

. A special case is the self-affine Sierpinski-type measure with

D
=

0

0

,

1

0

,

0

1

, which was considered by Dai, Fu and the author [ACHA, 2021], over which

R
=

3

k

1

0

0

3

k

2

for some

k

i

∈
N

, i = 1, 2.
Understanding Newton’s cradle. I: modelling the ideal cradle
Authors: Gauld Colin , Cross Rod
Published: January 2022

Newton’s cradle is often discussed in science classrooms as a clear example of the laws of conservation of momentum and energy although it has been shown that this use is somewhat misleading. Approaches to understanding the behaviour of this apparatus are often over-simplified and deficient or over-complex and with little impact among teachers. In this paper, basic principles of mechanics are used to explain the behaviour of ideal cradles of various lengths and to use a simple model by which to simulate its operation. The purpose is to demonstrate that the real behaviour of Newton’s cradle provides a rich source of application of those principles in coming to terms with how the apparatus behaves and experiencing the process of modelling in physics.
Covariant effective action for generalized Proca theories
Authors: Panda Sukanta , Tinwala Abbas Altafhussain , Vidyarthi Archit
Published: January 2022

We investigate the quantum stability of generalised Proca theories in curved spacetime treating gravity as a dynamical field. To compute the quantum gravitational corrections, we evaluate the divergent part of the effective action at one-loop level using Vilkovisky-DeWitt formalism, which gives us a gauge invariant and gauge condition independent effective action. It is shown that the quantum corrections are suppressed by a UV cutoff parametrically higher than the Proca mass, if the coupling constants are restricted to lie in a certain range. Furthermore, it is shown that the quantum corrections remain suppressed even at scales where classical non-linearities dominate over kinetic terms, allowing Vainshtein mechanism to work.
Investigation and control of laser pointing fluctuations on stability of terahertz time domain spectrometer
Authors: Mumtaz Muhammad , D Khan Sabih , Aslam Zia M , Shahzad Arslan , Ahmad Izhar
Published: January 2022

Terahertz time domain spectroscopy (THz-TDS) is a well known technique for analyzing materials in terahertz regime. The stability and reproducibility of the THz signal amplitude is most crucial for reliable measurements using this technique. In this article, an extensive investigation on the origin and the impact of beam pointing fluctuations on amplitude of THz signal is performed. These fluctuations have been reduced to minimum level with control on sources of beam pointing fluctuation including air turbulences and temperature drifts. Under these controlled conditions, the standard deviation in the measurement of refractive index and absorption coefficient have been reduced up to

1.3
×

10

−
4

and 0.2 cm−1, respectively.
Summary of the 13th IAEA technical meeting on plasma control systems, data management and remote experiments in fusion research
Authors: Waterhouse John , Barbarino Matteo
Published: January 2022

This report summarizes the contributions presented at the IAEA technical meeting on 13th IAEA technical meeting on plasma control systems, data management and remote experiments in fusion research, hosted by UKAEA and held virtually, on 5–8 July 2021. The meeting brought together 90 experts from nuclear fusion research sites worldwide. The main topics of the meeting were plasma control; machine control, monitoring, safety and remote manipulation; data acquisition and signal processing; database techniques for information storage and retrieval; advanced computing and massive data analysis; remote participation and virtual laboratory; and fast network technology and its application.
Violent relaxation in the Hamiltonian mean field model: II. Non-equilibrium phase diagrams
Authors: Santini Alessandro , Giachetti Guido , Casetti Lapo
Published: January 2022

A classical long-range-interacting N-particle system relaxes to thermal equilibrium on time scales growing with N; in the limit N → ∞ such a relaxation time diverges. However, a completely non-collisional relaxation process, known as violent relaxation, takes place on a much shorter time scale independent of N and brings the system towards a non-thermal quasi-stationary state (QSS). A finite system will eventually reach thermal equilibrium, while an infinite system will remain trapped in the QSS forever. For times smaller than the relaxation time, the distribution function of the system obeys the collisionless Boltzmann equation, also known as the Vlasov equation. The Vlasov dynamics are invariant under time reversal so that they do not ‘naturally’ describe the relaxational dynamics. However, as time grows the dynamics affect smaller and smaller scales in phase space, so that observables not depending upon small-scale details appear as relaxed after a short time. Herewith we present an approximation scheme able to describe violent relaxation in a one-dimensional toy-model, the Hamiltonian mean field. The approach described here generalizes the one proposed in Giachetti and Casetti (2019 J. Stat. Mech. 043201), which was limited to ‘cold’ initial conditions, to generic initial conditions, allowing us to predict non-equilibrium phase diagrams that turn out to be in good agreement with those obtained from the numerical integration of the Vlasov equation.
Direction-sweep Markov chains
Authors: Qin Liang , Höllmer Philipp , Krauth Werner
Published: January 2022

We discuss a non-reversible, lifted Markov-chain Monte Carlo (MCMC) algorithm for particle systems in which the direction of proposed displacements is changed deterministically. This algorithm sweeps through directions analogously to the popular MCMC sweep methods for particle or spin indices. Direction-sweep MCMC can be applied to a wide range of reversible or non-reversible Markov chains, such as the Metropolis algorithm or the event-chain Monte Carlo algorithm. For a single two-dimensional tethered hard-disk dipole, we consider direction-sweep MCMC in the limit where restricted equilibrium is reached among the accessible configurations for a fixed direction before incrementing it. We show rigorously that direction-sweep MCMC leaves the stationary probability distribution unchanged and that it profoundly modifies the Markov-chain trajectory. Long excursions, with persistent rotation in one direction, alternate with long sequences of rapid zigzags resulting in persistent rotation in the opposite direction in the limit of small direction increments. The mapping to a Langevin equation then yields the exact scaling of excursions while the zigzags are described through a non-linear differential equation that is solved exactly. We show that the direction-sweep algorithm can have shorter mixing times than the algorithms with random updates of directions. We point out possible applications of direction-sweep MCMC in polymer physics and in molecular simulation.
Locally equivalent quasifree states and index theory
Authors: Bourne Chris
Published: January 2022

We consider quasifree ground states of Araki’s self-dual canonical anti-commutation relation algebra from the viewpoint of index theory and symmetry protected topological (SPT) phases. We first review how Clifford module indices characterise a topological obstruction to connect pairs of symmetric gapped ground states. This construction is then generalised to give invariants inKO*(Ar)withAaC*,r-algebra of allowed deformations. WhenA=C*(X), the Roe algebra of a coarse spaceX, and we restrict to gapped ground states that are locally equivalent with respectX, aK-homology class is also constructed. The coarse assembly map relates these two classes and clarifies the relevance ofK-homology to free-fermionic SPT phases.
Model experiments for Czochralski crystal growth processes using inductive and resistive heating
Authors: Enders-Seidlitz A , Pal J , Dadzis K
Published: January 2022

The Czochralski (CZ) growth technique is widely applied in crystal growth, using both induction and resistance heaters. In this work, a novel model experiment platform with comprehensive in-situ measurement capability is introduced. Growth experiments with the model material tin applying both heating concepts are performed and analyzed, e.g., in terms of the maximum achievable crystal diameter. Strong asymmetries in the magnetic field of the induction heater are measured and temperature distribution on the resistance heater is found to be non-uniform. Furthermore, significant losses are observed in the power supplies of the resistance heater. The heating efficiency of both concepts is compared considering different insulation geometries. The obtained results show the capability of model experiments for design optimization and will provide valuable input for further validation of numerical simulations.
Twenty Years’ Research on Microwave Application to Metal Production and Recycling
Authors: Yoshikawa Noboru
Published: January 2022

Ever since discovery of microwave heating in 1946, its application has been developed in various fields. Our research group has performed intensive studies on microwave heating application to metal production and recycling for these twenty years. In this article, it is intended to introduce our attempts having made for different projects. They are 1. Microwave processing of Ti bearing blast furnace slag, microstructural alteration and comminution. 2. Microwave carbo-thermic reduction of valuable metals from various oxides. 3. Microwave drying and dehydration of wet wastes. 4. Vapor de-phosphorization by microwave rapid heating. It is to be emphasized that we utilized a single mode microwave applicator for the purpose of clarification on the heating mechanisms of various metallurgical matters and compounds, and it was intended to discuss the reaction kinetics excited by microwave heating.
Durable, self-cleaning and anti-fouling superhydrophobic coating based on double epoxy layer
Authors: Li Xiang , Liu Hua , Zhang Yingbing , Liu Zuozhen
Published: January 2022

The practical application of superhydrophobic coatings has been greatly restricted due to the complicated preparation and fragile hierarchical structures on the surface. In this study, we prepared a robust superhydrophobic coating with a double-layer structure via a low-cost and facile method, adhering the non-wettability layer composed of silica nanoparticles and fluorine-modified epoxy resin to a binder resin layer on aluminum. The fluorine-modified epoxy resin with low surface energy can fix the silica nanoparticles after curing and cross-link with the adhesive layer. When the SiO2 content in the surface layer is 40%, the water contact angle (WCA) of the coating is 162°, and the sliding angle (SA) is 2°. In the mechanical performance test, the durable coating can remain superhydrophobic even after 260 cycles of friction or 160 cycles of tape peeling. In addition, the superhydrophobic coating with self-cleaning and anti-fouling properties also has the performance of acid-base solution resistance. Hence, the combination of the rough layer and the adhesive layer makes the practical application of artificial superhydrophobic coatings possible.
On Variance of the Treatment Effect in the Treated When Estimated by Inverse Probability Weighting
Authors: Reifeis Sarah A , Hudgens Michael G
Published: January 2022

In the analysis of observational studies, inverse probability weighting (IPW) is commonly used to consistently estimate the average treatment effect (ATE) or the average treatment effect in the treated (ATT). The variance of the IPW ATE estimator is often estimated by assuming that the weights are known and then using the so-called “robust” (Huber-White) sandwich estimator, which results in conservative standard errors (SEs). Here we show that using such an approach when estimating the variance of the IPW ATT estimator does not necessarily result in conservative SE estimates. That is, assuming the weights are known, the robust sandwich estimator may be either conservative or anticonservative. Thus, confidence intervals for the ATT using the robust SE estimate will not be valid, in general. Instead, stacked estimating equations which account for the weight estimation can be used to compute a consistent, closed-form variance estimator for the IPW ATT estimator. The 2 variance estimators are compared via simulation studies and in a data analysis of the association between smoking and gene expression.
Evaluating Confounding Control in Estimations of Influenza Antiviral Effectiveness in Electronic Health Plan Data
Authors: Htoo Phyo T , Measer Gregory , Orr Robert , Bohn Justin , Sorbello Alfred , Francis Henry , Dutcher Sarah K , Cosgrove Austin , Carruth Amanda , Toh Sengwee , Cocoros Noelle M
Published: January 2022

Observational studies of oseltamivir use and influenza complications could suffer from residual confounding. Using negative control risk periods and a negative control outcome, we examined confounding control in a health-insurance-claims–based study of oseltamivir and influenza complications (pneumonia, all-cause hospitalization, and dispensing of an antibiotic). Within the Food and Drug Administration’s Sentinel System, we identified individuals aged ≥18 years who initiated oseltamivir use on the influenza diagnosis date versus those who did not, during 3 influenza seasons (2014–2017). We evaluated primary outcomes within the following 1–30 days (the primary risk period) and 61–90 days (the negative control period) and nonvertebral fractures (the negative control outcome) within days 1–30. We estimated propensity-score–matched risk ratios (RRs) per season. During the 2014–2015 influenza season, oseltamivir use was associated with a reduction in the risk of pneumonia (RR = 0.72, 95% confidence interval (CI): 0.70, 0.75) and all-cause hospitalization (RR = 0.54, 95% CI: 0.53, 0.55) in days 1–30. During days 61–90, estimates were near-null for pneumonia (RR = 1.04, 95% CI: 0.95, 1.15) and hospitalization (RR = 0.94, 95% CI: 0.91, 0.98) but slightly increased for antibiotic dispensing (RR = 1.14, 95% CI: 1.08, 1.21). The RR for fractures was near-null (RR = 1.09, 95% CI: 0.99, 1.20). Estimates for the 2016–2017 influenza season were comparable, while the 2015–2016 season had conflicting results. Our study suggests minimal residual confounding for specific outcomes, but results differed by season.
Living in mixed-sex groups limits sexual selection as a driver of pelage dimorphism in bovids
Authors: D’Ammando Giacomo , Franks Daniel W , Bro-Jørgensen Jakob
Published: January 2022

Among mammals, bovids provide some of the most striking examples of sexual dimorphism in colouration and pelage appendages, such as beards and manes. This dimorphism is usually assumed to have evolved through sexual selection on males in the context of intra- or intersexual communication. However, the sexes coloration and pelage appendages look similar between the two sexes in several bovid species thought to be characterized by large opportunities for sexual selection, hinting at fitness costs of dimorphic traits due to other selection pressures. This study applies the comparative method with phylogenetic control to identify the factors promoting and constraining the evolution of dimorphism in coloration and pelage appendages across bovids. We found that trait dimorphism correlated positively with large breeding group size, an indicator of the intensity of sexual selection, and negatively with male territoriality, which is also likely to affect the operation of sexual selection. The relative rarity of color and pelage dimorphism in species with territorial mating systems may be explained by weaker sexual selection due to difficulty in monopolizing females and/or sexual selection targeting other traits, such as territorial quality as an extended phenotype. We also found that dimorphism in color and pelage was reduced in species spending more time in mixed-sex groups outside the breeding season, possibly due to increased predation costs from non-uniformity. This suggests that benefits from integration into mixed-sex groups select against the extravagant male morphologies otherwise promoted by sexual selection.
Evolution of European carnivorous mammal assemblages through the Palaeogene
Authors: Solé Floréal , Fischer Valentin , Le Verger Kévin , Mennecart Bastien , Speijer Robert P , Peigné Stéphane , Smith Thierry
Published: January 2022

The rise of Carnivora (Mammalia: Laurasiatheria) is an important evolutionary event that changed the structure of terrestrial ecosystems, starting at the dawn of the Eocene, 56 Mya. This radiation has been mainly analysed in North America, leaving the evolution of carnivoran diversity in other regions of the globe poorly known. To tackle this issue, we review the evolution of terrestrial carnivorous mammal diversity (Mesonychidae, Oxyaenidae, Hyaenodonta and Carnivoramorpha) in Europe. We reveal four episodes of intense faunal turnovers that helped establish the dominance of carnivoramorphans over their main competitors. We also identify two periods of general endemism. The remaining time intervals are characterized by dispersals of new taxa from North America, Asia and Africa. The European Palaeogene carnivorous mammal fauna appears to have been almost constantly in a transient state, strongly influenced by dispersals. Many of the bioevents we highlight for European carnivorous mammals are probably best seen as ecosystem-wide responses to environmental changes. In contrast to the North American record, European hyaenodonts remain more diverse than the carnivoramorphans for the entire Eocene. The replacement of hyaenodonts by carnivoramorphans as the most diverse and dominant predators only occurred after the ‘Grande Coupure’ at 33 Mya, about 16 Myr later than in North America.
Five questions toward mRNA degradation in oocytes and preimplantation embryos: when, who, to whom, how, and why?
Authors: Jiang Zhi-Yan , Fan Heng-Yu
Published: January 2022

RNA—the primary product of the genome—is subject to various biological events during its lifetime. During mammalian gametogenesis and early embryogenesis, germ cells and preimplantation embryos undergo marked changes in the transcriptome, including mRNA turnover. Various factors, including specialized proteins, RNAs, and organelles, function in an intricate degradation system, and the degradation selectivity is determined by effectors and their target mRNAs. RNA homeostasis regulators and surveillance factors function in the global transcriptome of oocytes and somatic cells. Other factors, including BTG4, PABPN1L, the CCR4-NOT subunits, CNOT6L and CNOT7, and TUTs, are responsible for two maternal mRNA avalanches: M- and Z-decay. In this review, we discuss recent advances in mRNA degradation mechanisms in mammalian oocytes and preimplantation embryos. We focused on the studies in mice, as a model mammalian species, and on RNA turnover effectors and the cis-elements in targeting RNAs.
Future of biomedical, agricultural, and biological systems research using domesticated animals
Authors: Spencer Thomas E , Wells Kevin D , Lee Kiho , Telugu Bhanu P , Hansen Peter J , Bartol Frank F , Blomberg LeAnn , Schook Lawrence B , Dawson Harry , Lunney Joan K , Driver John P , Davis Teresa A , Donovan Sharon M , Dilger Ryan N , Saif Linda J , Moeser Adam , McGill Jodi L , Smith George , Ireland James J
Published: January 2022

Increased knowledge of reproduction and health of domesticated animals is integral to sustain and improve global competitiveness of U.S. animal agriculture, understand and resolve complex animal and human diseases, and advance fundamental research in sciences that are critical to understanding mechanisms of action and identifying future targets for interventions. Historically, federal and state budgets have dwindled and funding for the United States Department of Agriculture (USDA) National Institute of Food and Agriculture (NIFA) competitive grants programs remained relatively stagnant from 1985 through 2010. This shortage in critical financial support for basic and applied research, coupled with the underappreciated knowledge of the utility of non-rodent species for biomedical research, hindered funding opportunities for research involving livestock and limited improvements in both animal agriculture and animal and human health. In 2010, the National Institutes of Health and USDA NIFA established an interagency partnership to promote the use of agriculturally important animal species in basic and translational research relevant to both biomedicine and agriculture. This interagency program supported 61 grants totaling over $107 million with 23 awards to new or early-stage investigators. This article will review the success of the 9-year Dual Purpose effort and highlight opportunities for utilizing domesticated agricultural animals in research.
The interleukin-6 trans-signaling promotes progesterone production in human granulosa-lutein cells
Authors: Li Sai-Jiao , Chang Hsun-Ming , Wang Jeremy H , Yang Jing , Leung Peter C K
Published: January 2022

As a critical paracrine regulator of multiple reproductive functions, the cytokine interleukin-6 (IL-6) is expressed in human granulosa cells and can be detected in follicular fluid. At present, the functional role of IL-6 in the regulation of ovarian steroidogenesis is controversial. Moreover, the detailed molecular mechanisms by which IL-6 regulates the production of progesterone in human granulosa cells remain to be elucidated. In the present study, we used primary and immortalized human granulosa-lutein (hGL) cells to investigate the effects of IL-6 on progesterone synthesis and the underlying molecular mechanisms. We found that IL-6 trans-signaling by the combined addition of IL-6 and soluble IL-6 receptor (sIL-6Rα)-induced steroidogenic acute regulatory expression and progesterone production in hGL cells. Additionally, IL-6/sIL-6Rα activated the phosphorylation of Janus activated kinase 2 (JAK2) and signal transducer and activator of transcription 3 (STAT3), and the cellular effects were abolished by AG490 (JAK2 inhibitor), C188-9 (STAT3 inhibitor), or siRNA-mediated knockdown of STAT3. IL-6 trans-signaling-induced activation of JAK2/STAT3 also upregulated the expression of suppressor of cytokine signaling 3, which, in turn, negatively regulated the JAK2/STAT3 pathway by suppressing STAT3 activation and its downstream effects. Our findings provide insight into the molecular mechanisms by which IL-6 trans-signaling modulates steroidogenesis in hGL cells.
Blocking serine protease activity prevents semenogelin degradation leading to hyperviscous semen in humans
Authors: Anamthathmakula Prashanth , Erickson Jeffery A , Winuthayanon Wipawee
Published: January 2022

Prostate-specific antigen (PSA) is a prostate-specific serine protease enzyme that hydrolyzes gel-forming proteins (semenogelins) and changes the semen from gel-like to watery viscosity, a process called semen liquefaction. Highly viscous semen and abnormal liquefaction reduce sperm motility and contribute to infertility. Previously, we showed that nonspecific serine protease inhibitor (AEBSF) prevented proteolytic degradation of semenogelin in mice. However, it is unclear whether similar effect could be recapitulated in fresh human ejaculates. Therefore, in this study we evaluated the effect of AEBSF on the degradation of semenogelin (SEMG1) and its subsequent impact on semen liquefaction and sperm motility in fresh semen ejaculates collected from healthy men. We found that AEBSF showed a dual contraceptive action where it effectively 1) prevented degradation of SEMG1 resulting in viscous semen and 2) decreased sperm motility in human semen samples. However, the impact of AEBSF on sperm motility and viability could be due to its inhibitory activity toward other serine proteases or simply due to its toxicity. Therefore, to determine whether inhibition of PSA activity alone could disrupt SEMG1 degradation and contribute to hyperviscous semen, a neutralizing PSA antibody was used. We found that PSA antibody effectively prevented SEMG1 degradation with a subtle impact on sperm motility. These findings suggest that the target inhibition of PSA activity can prevent proteolytic degradation of SEMG1 and block liquefaction process, resulting in hyperviscous semen. As it is currently unknown if blocking semen liquefaction alone could prevent pregnancy, it needs further extensive studies before drawing any translational conclusions.
The Coronavirus Act’s Easements to the Care Act 2014: A Pragmatic Response or a Red Herring?
Authors: Baginsky Mary , Thomas Emily , Manthorpe Jill
Published: January 2022

Easements to the Care Act 2014 were introduced in England in Spring 2020 to support local authorities (LAs) who were dealing with the impact of COVID-19 on adult social care. They were adopted by a small number of LAs that only kept them in place for a very short period. This article draws on the limited literature covering easements and on a synthesis of the views of twenty key informants with professional experiences of social care policy, advocacy, practice and law. It covers the way they were introduced and the opposition which they attracted, as well as contrasting views on the nature and necessity of easements. It also records the perceptions of interviewees on the rationale for the decisions taken to adopt or not adopt them. The article examines the reasons why government thought they should be in place and the concerns of some of those in the voluntary, human rights and legal sectors who challenged their introduction and operation. Whilst the findings contain messages for how to approach the management of a similar crisis in the future, the study identified a lack of evidence of the impact of easements on those using social care as well as their carers.
Devolved Budgets in Children’s Social Care: A Logic Model Based on Three Pilot Evaluations
Authors: Westlake David , Corliss Cindy , Thompson Sarah , Meindl Melissa , Diaz Clive , Talwar Ria , Folkes Louise
Published: January 2022

A lack of basic resources and financial difficulties affect many families and increase risks to children. Social workers’ ability to help is limited by scarce resources, and managers usually control the financial and material help that is available, making it difficult to access directly. This article reports on a mixed methods evaluation of ‘devolved budgets’ (DBs), an intervention where social workers could use up to £10,000 to help families directly and reduce the need for children to enter care. The devolution of decision making to workers was a key feature of the intervention, and many needed encouragement and support to use DBs, exercised caution and spent less than expected. Resources were used to access additional help quickly, though often in circumstances where there was no immediate likelihood of a child entering care. We present a logic model which delineates two pathways through which we theorise DBs to operate: by (1) resources being dedicated to a family’s needs and (2) improved worker–family relationships. By illustrating the erosion of practical support within the social work role, our findings substantiate critiques of managerialism. As a way forward, we argue for greater trust in social workers’ judgement.
Preliminary studies on variation in the micromorphology of the seed coat inHabenaria s.l.(Orchidaceae) and relatives
Authors: Rewicz Agnieszka , Kolanowska Marta , Kras Marta , Szlachetko Dariusz L
Published: January 2022

There are many studies on the biology, ecology and infrageneric classification of the cosmopolitan orchid genus Habenaria. However, there are few data on the seed morphology of species in this genus. The aim of this study was to analyse the seed morphology of Habenaria and related taxa (111 species in total). The species of Habenaria s.l. studied are mostly characterized by a scobiform seed, but the form of individual seed coat cells varies between and among some species. In most of the species analysed, the cell walls are arranged mostly along the main axis of a seed. The size of the embryos and the volume of seeds and embryos also varied in Habenaria. The periclinal wall of the cells in the seed coat of most of the taxa examined is smooth, but there are several species with distinct ornamentation on this wall (slanting ridges, transverse ridges, reticulate ridges). The periclinal wall could be used in taxonomic delimitations, especially when combined with additional features such as seed size, shape and arrangement of the cells in the seed coat. Although many of the morphological groups in Habenaria s.l. were included in this study, no qualitative seed characters that could be helpful in establishing an alternative infrageneric division of this taxon were previously recognized.