Broadband light absorption is a basis for the proper functionality of various materials, microstructures, and devices. Despite numerous studies, however, many aspects of broadband absorption remain ...uncovered. In this paper, we demonstrate an inverse-problem approach to designing nanostructures with a very low optical reflection and high absorption through a frequency band. Particular emphasis is made on a subwavelength transparent film as a top layer and anisotropic substrate. The polarization-dependent metamaterial absorber based on a subwavelenth semiconductor multicomponent multilayer structure is proposed and numerically investigated. For an illustration, we consider a four-component heavily doped silicon lattice with a thin undoped silicon top layer. The dielectric response of the structure is engineered by controlling the free carrier density and filling factor of each layer. A simulation study reveals a power law dependence of the bandwidth on the maximum reflectivity within the band.
A system of four magnets which is a part of the SPASCHARM experimental setup at the U-70 accelerator facility for the study of spin effects in hadronic interactions is described. An unique magnet ...with the field of 2.4 T and a field uniformity at the level of 10
–4
in a working volume of 60 cm
3
is used to pump up and hold polarization in a polarized proton frozen target. A special wide-aperture magnet is the central part of the spectrometer of the setup based on the drift tubes. For precision steering the beam to the center of the target, two small magnets correctors developed by the Efremov Research Institute of Electrophysical Equipment have been manufactured and introduced into the setup.
Persistence is a phenomenon in which bacteria avoid the lethal effects of antibiotics due to their transition to a physiological state, which enables tolerance to antibacterial drugs. Among the ...factors that contribute to persistence, a special role belongs to toxin–antitoxin (TA) systems, which are involved in the regulation of a wide range of physiological processes and have a significant effect on the results of antibiotic therapy. This review examines the mechanisms of the participation of TA systems in the formation of persistent bacteria, as well as the clinical importance of the phenomenon of persistence and methods for the control of phenotypically tolerant cells via regulation of the activity level of TA modules.
—
A high-resolution scintillating fiber hodoscope comprising multi-anode photomultiplier tubes is presented. The technologies for manufacturing fiber bundles and mounting them into the detector ...housing are described in detail. The functional diagram of the anode-signal discriminator and the characteristics of the hodoscope operating as the part of an experimental setup at the beamline 14 of the U-70 accelerator complex are presented.
First results on
-dependence measurements in inclusive
meson production in
interactions (
, Al, Cu, Sn, and W) are presented at
GeV/
c
. The ratios of the differential cross sections of four of these ...nuclei to the differential cross section on aluminum were measured and the dependence of these cross sections on the atomic of the nucleus was studied. The measurements were carried out in the kinematic region of the Feynman variable
and transverse momentum
GeV/
c
.
mesons were detected in the decay mode
at the SPASCHARM experimental setup using negative charged beams at beamline 14 of the U-70 accelerator complex.
Two new hybrid iodoantimonates(
iii
), (3-C
5
H
12
NO)
4
Sb
4
I
16
· 2 H
2
O (
1
, 3-C
5
H
12
NO
+
is 3-hydroxypiperidinium) and (4-C
5
H
12
NO)
4
Sb
4
I
16
· 3 H
2
O (
2
, 4-C
5
H
12
NO
+
is 4- ...hydroxypiperidinium), were synthesized. Their crystal structures were established. The anionic substructures of the new compounds are composed of the same tetranuclear complex anions Sb
4
I
16
4−
. The differences in the structure of 3-hydroxypiperidine and 4-hydroxypiperidine are responsible for the differences in the supramolecular organization of the cationic substructures and in the packing of the structural units. The comparative analysis of hydrogen bonding systems in the structures of compounds
1
and
2
was carried out. The band gap width for compound
1
was estimated at 2.38 eV according to the direct band gap model and at 2.28 eV in terms of the indirect band gap model.
The review is devoted to the use of the CRISPR/Cas system for obtaining knockdowns of target bacterial genes by CRISPR-mediated interference (CRISPRi). CRISPRi is based on the preservation of the ...ability of the inactivated dCas nuclease in complex with guide RNA to bind a target, which leads to reversible repression of the selected genes. The review describes the principle of operation of CRISPR/Cas and CRISPRi/dCas and provides examples of various approaches to the use of CRISPRi with the most popular inactivated nucleases dCas9 and dCas12a. Also, attention is paid to the use of CRISPRi screening for genome-wide studies and the modular system for identifying many important patterns at the Mobile-CRISPRi genome level. In addition, we discuss the use of CRISPRi to optimize biotechnological production, such as the synthesis of malonyl-CoA, L-lysine, L-glutamate, and other significant products.
New organic-inorganic hybrid halometallates of the general formula (HpipeH
2
)-M
2
X
10
· 2H
2
O, where M = Sb, Bi; X = Br, I; Hpipe is homopiperazine (C
5
N
2
H
12
), were synthesized. The crystal ...structures of three new compounds, α-(HpipeH
2
)
2
Sb
2
I
10
· 2H
2
O
(1)
, β-(HpipeH
2
)
2
Sb
2
I
10
)-2H
2
O
(2)
, and (HpipeH
2
)
2
Bi
2
Br
10
· 2H
2
O
(3)
, were determined and analyzed in comparison with the previously synthesized analog (HpipeH
2
)
2
Bi
2
I
10
· 2H
2
O
(4).
All four compounds have similar crystal structures, in which inorganic dioctahedral M
2
X
10
4−
anions alternate with organic (HpipeH
2
)
2+
cations and water molecules to form 3D systems based on (N)H⋯X, (N)H⋯O, and (O)H⋯X hydrogen bonds. In all structures, the (HpipeH
2
)
2+
cation serves the same template function, forming three (N)H⋯X hydrogen bonds with halogen atoms of the inorganic anion and one (N)H⋯O bond with a water molecule. In going from Sb to Bi and from I to Br, the band gap width increases and reaches 2.89 eV for compound
3
.
Generation of ultrawideband electromagnetic radiation by a vacuum photodiode with a plane cesium antimonide photocathode is studied. Thin aluminum plates deposited on a sapphire input window serve as ...the anode of the photodiode. Electron emission from the photocathode is initiated by the second-harmonic radiation (λ = 385 nm) of a titanium–sapphire laser system with a pulse duration of about 200 fs. Variations in the electric component of the electromagnetic radiation due to changes of the voltage across the interelectrode gap from 13 to 140 kV are measured.
Identification of the inbred lines perspective for combining abilities of winter rye is an important stage in the hybrid breeding cycle. The objective of the surveys is to evaluate the general and ...specific combining abilities of the inbred lines of winter rye with a topcross method. Thirty rye homozygous lines carrying the sterility-inducing cytoplasm of the Pampa type served as the maternal inheritance patterns. Four male fertile homozygous lines mfН-1432, mfН-1423, mfН-1147, and mfН-1842 were used as testers. Test crossings were performed on the spatially isolated fields in 2019. Overall, 120 simple interlinear F1 hybrids were produced. Their testing was carried out on the plots of 8.0-m
2
area with two field replicates. The Valdai cultivar was used as a standard at the population level. The F1 hybrid crop yields varied from 5.08 to 7.55 t/ha at the parameter average value of 6.27 t/ha within the experiment. The hybrids containing lines msН-1185-1 were considered highest-yielding crops. Their crop yields varied from 6.92 to 7.48 t/ha relative to the tester. Frequency of occurrence of hybrids F1 with reliably high competitive heterosis comprised 20 of 120, or 16.7%. Both the general (GCA) and specific (SCA) combining abilities made the essential contribution to dispersion of the crop-related traits. In addition, the portions of the GCA and SCA effects comprised 91.2 and 6.9% of dispersion of the crop-related traits, respectively. A high variance GCA/SCA ratio indicates rather substantial genetic divergence between the inbred lines used in breeding. Rather high GCA is recorded for seven sterile lines, such as msH-1185-1, msH-1185-2, msН-1179, msН-1238, msН-700, msН-48, and msН-1247. The line mfН-1147 was considered best on GCA among the tester lines. Lines msН-451, msН-577, msН-842, msH-1185-2, and msН-1190 and testers mfН-1432 and mfН-1423 showed great SCA effects. The average crop yield of the hybrids containing lines of high GCA was reliably higher than that in the hybrids containing lines of high SCA (6.76 vs. 6.24 t/ha, true T-value
T
fact
= 3.38 >
T
05
= 2.22). However, nine sterile lines possessed significantly lower GCA. A positive correlation between the line GCA effects and the levels of their crop yields was revealed (
r
= 0.59, true T-value
T
fact
= 2.30 >
T
05
= 2.22).
