•Concentration of deep electron traps is in the range of 1019 cm−3 posing challenges for electrostatic control of HfO2- and HZO-based ferroelectric devices.•Trap energy distribution universally ...exhibit three characteristic optical energy levels: around 2 eV, 3 eV, and 4 eV below the oxide CB.•The observed traps are likely intrinsic to HfO2 lattice rather than related to dopants or ZrO2 sub-network.
Electron traps in HfO2-based ferroelectric layers are known to be a major performance-degrading factor. We use room temperature charge injection and photodepopulation techniques to reveal the trap density and energy distribution in ferroelectric HfO2 and HfZrO4. The concentration of occupied electron traps is in the order of 1019 cm−3 for all analyzed samples which provides the lower limit of the defect concentration in the film. Energy distributions universally exhibit three characteristic optical energy levels: around 2 eV, 3 eV, and 4 eV below the HfO2 conduction band edge. The latter energy level was not observed previously and, according to previous DFT calculations, is too deep to be either of polaronic or O-vacancy-related nature. Nevertheless, the trap energy spectrum remains very similar in all studied samples suggesting the same sorts of the dominant electron traps both in HfO2 and HfZrO4 probably related to intrinsic defects of the HfO2 sub-network.
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•We revealed trap energies and densities in FE and non-FE HfO2 and HfZrO4 layers.•The high deep trap density (~1019 cm−3) poses challenges for electrostatic control.•The observed traps are likely ...intrinsic to hafnia/zirconia lattice (polarons).
Electron trapping in ferroelectric and non-ferroelectric HfO2-based layers was studied at room temperature by charge injection and photodepopulation techniques. The comparison of inferred energy distribution and density of trapped electrons in differently processed samples shows insignificant impact of Al- and Si-doping on trapping properties suggesting intrinsic nature of the observed traps. A comparison to the HfZrO4 layers is provided. The volume concentration of deep traps, most of which are energetically distributed between 2 and 3.5 eV below the HfO2 conduction band, is found to be in the range of 1019 cm−3.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Renal cancer ranks 10
in the mortality structure of the Russian Federation. The introduction of checkpoint inhibitors has changed the paradigm of treatment of patients with malignant neoplasms.
Data ...from clinical trials have shown good progression-free median and median overall survival. Each cancer center has been accumulating its own experience in treating patients with renal cell cancer by applying modern target drugs and immunotherapy.
In routine clinical practice, oncologists do not get the results that have been demonstrated in clinical trials when evaluating the effectiveness of the therapy.
In this single-center clinical study, we discuss the results of using nivolumab as mono-therapy and the combination of nivolumab with ipilimumab in metastatic renal parenchyma cancer patients.
•We present a universal method for shallow traps characterization in high-k oxides.•We observed a huge number of shallow traps (1019–1020 cm−3) in all studied samples.•Shallow trapping behavior is ...similar in studied oxide materials (HfO2, ZrO2, LaSiOx).
In the present work the use of low temperature (77 K) charge injection and thermally activated emission is proposed as a universal method for characterization of shallow traps in high permittivity insulating oxides (HfO2, ZrO2, LaSiOx). A broad temperature range (77 K–300 K) allows one to evaluate density and energy distribution of electron traps within the energy depth range ≈1 eV below the oxide conduction band. The volume concentration of these traps is found to be in the range of 1019–1020 cm−3 in all studied materials indicating that shallow trapping will significantly affect performance of the high-k oxide-based devices operating at low temperature and/or very short pulse times.
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A new rotating generalization of the Damour–Solodukhin wormhole (RDSWH), called Kerr-like wormhole, has recently been proposed and investigated by Bueno et al. for echoes in the gravitational wave ...signal. We show a novel feature of the RDSWH, viz., that the kinematic properties such as the ISCO or marginally stable radius
r
ms
, efficiency
ϵ
and the disk potential
V
eff
are
independent
of
λ
(which means they are identical to their KBH counterparts for any given spin). Differences however appear in the emissivity properties for higher values
0.1
<
λ
≤
1
(say) and for the extreme spin
a
⋆
=
0.998
. The kinematic and emissivity are generic properties as variations of the wormhole mass and the rate of accretion within the model preserve these properties. Specifically, the behavior of the luminosity peak is quite opposite to each other for the two objects, which could be useful from the viewpoint of observations. Apart from this, an estimate of the difference
Δ
λ
in the maxima of flux of radiation
F
(
r
) shows non-zero values but is too tiny to be observable at present for
λ
<
10
-
3
permitted by the strong lensing bound. The broad conclusion is that RDSWH are experimentally indistinguishable from KBH by accretion characteristics.
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It seems surprising that the emissivity properties of the accretion disk (
à la
Page and Thorne) surrounding the Gibbons–Maeda–Garfinkle–Horowitz–Strominger (GMGHS) black holes of heterotic string ...theory have not yet been studied. To fill this gap in the literature, we study the emissivity properties of the thin accretion disks around these black holes both in the Einstein and in the string frame using the Page–Thorne model. For illustration, we choose as a toy model a stellar-sized spherically symmetric black hole and find that, while the emissivity properties do not significantly differ from those of Reissner–Nordström and Schwarzschild black holes, they remarkably differ at GMGHS extreme limits corresponding to naked singularity and wormhole at higher frequencies. These differences provide a novel way to speculatively conclude about different types of objects from the observational point of view.
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We first advance a mathematical novelty that the three geometrically and topologically distinct objects mentioned in the title can be exactly obtained from the Jordan frame vacuum Brans I solution by ...a combination of coordinate transformations, trigonometric identities and complex Wick rotation. Next, we study their respective accretion properties using the Page–Thorne model which studies accretion properties exclusively for
r
≥
r
ms
(the minimally stable radius of particle orbits), while the radii of singularity/throat/horizon
r
<
r
ms
. Also, its Page–Thorne efficiency
ϵ
is found to increase with decreasing
r
ms
and also yields
ϵ
=
0.0572
for Schwarzschild black hole (SBH). But in the singular limit
r
→
r
s
(radius of singularity), we have
ϵ
→
1
giving rise to
100
%
efficiency in agreement with the efficiency of the naked singularity constructed in 10. We show that the differential accretion luminosity
d
L
∞
d
ln
r
of Buchdahl naked singularity (BNS) is always substantially larger than that of SBH, while Eddington luminosity at infinity
L
Edd
∞
for BNS could be arbitrarily large at
r
→
r
s
due to the scalar field
ϕ
that is defined in
(
r
s
,
∞
)
. It is concluded that BNS accretion profiles can still be higher than those of regular objects in the universe.
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A method for determining the basic energy characteristics of a hybrid car engine is presented. The technique takes into account parameters of the vehicle and parameters of the driving mode during ...operation. The basis of the technique is traction power and energy calculation. According to the source data, the flow of energy passing through mechanical, electrical chains and through the storage of electrical energy is determined. The technique is implemented in the form of algorithms for the calculation program and allows one to simultaneously receive the main technical characteristics of the vehicle when it is equipped with a hybrid engine of a sequential, parallel and mixed type. The presented method allows one to obtain the following values: the required power of the internal combustion engine, the required power of the motor generator, the minimum capacity of the electrical energy storage device, the estimated fuel consumption. This article presents an example of calculating the basic parameters of a combined power plant for a car weighing 1500 kg when driving it along the standard European driving test cycle. Similar calculations can also be carried out for any other cycle and parameters of the vehicle, including the bus, truck, and tractor.
Proteins perform their functions in solution but their structures are most frequently studied inside crystals. Here we probe how the crystal packing alters microsecond dynamics, using solid-state NMR ...measurements and multi-microsecond MD simulations of different crystal forms of ubiquitin. In particular, near-rotary-resonance relaxation dispersion (NERRD) experiments probe angular backbone motion, while Bloch-McConnell relaxation dispersion data report on fluctuations of the local electronic environment. These experiments and simulations reveal that the packing of the protein can significantly alter the thermodynamics and kinetics of local conformational exchange. Moreover, we report small-amplitude reorientational motion of protein molecules in the crystal lattice with an ~3-5° amplitude on a tens-of-microseconds time scale in one of the crystals, but not in others. An intriguing possibility arises that overall motion is to some extent coupled to local dynamics. Our study highlights the importance of considering the packing when analyzing dynamics of crystalline proteins.X-ray crystallography is the main method for protein structure determination. Here the authors combine solid-state NMR measurements and molecular dynamics simulations and show that crystal packing alters the thermodynamics and kinetics of local conformational exchange as well as overall rocking motion of protein molecules in the crystal lattice.
It is well known that the Einstein-scalar system of general relativity can in principle yield non-unique exact spinning naked singularities, which lead to unique Kerr black hole when the scalar field ...is switched off. It is a challenging task to observationally distinguish these two types of objects. Since accretion process could be a viable diagnostic for this distinction, the purpose of the present work is to explore whether there could be features in the accretion profiles distinguishing the singularity from a Kerr black hole. Here we study the Novikov–Thorne thin accretion to a
new
spinning naked singularity with a scalar charge
σ
recently reported by Bogush and Gal’tsov (BG). Our study reveals that: (1) the conversion efficiency
ϵ
of the BG naked singularity is
independent
of
σ
and (2) the maxima of emissivity profiles for the BG singularity tend to shift towards the inner disk ISCO boundary
r
=
r
ms
and peak at a value significantly larger than those of a Kerr black hole with the increase of
a
,
σ
and relative shrinking of
-
g
. All these effects are
quantitatively
tabulated, which reveal, for instance, that the flux from the naked singularity could be as high as
10
5
times larger than that of a Kerr black hole. Since these distinguishing features are known to be shared also by other models of naked singularity, it is tempting to speculate that such behavior could be hallmark of naked singularities.
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