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"Lebedev, V. A."
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حفريات تحت سفح الأهرامات : مصر في عيون الأثريين الروس
يتضمن هذا الكتـاب بين طياته سـردا مفصلا عن النجاحـات التى قام بها طاقم البعثة الأثرية الروسـية على مدار سنوات عديدة السـنوات، حيث يزيل اللثام عن الاكتشـافات التى توصلوا إليها حتى هذه اللحظة، كما يقدم نبذة عن أعمال البعثة اليومية وتفاصيل حياتها أيضا، فضلا عن التنقيبات التى قام بها الأثريـون فى مصر، بلغة علمية دقيقة. ويتضمن الكتاب جزأين الجزء الأول بعنوان \"حفريات تحت سفح الهرم\" ويتكون من ثمانية فصول، والجزء الثانى بعنوان \"علم الآثار المصرى فى بداية القرن الحادى والعشرون\"، ويتكون من ثلاثة فصول.
BOOK
COVID-19 conspiracy ideation is associated with the delusion proneness trait and resistance to update of beliefs
The rapid spread of conspiracy ideas associated with the recent COVID-19 pandemic represents a major threat to the ongoing and coming vaccination programs. Yet, the cognitive factors underlying the pandemic-related conspiracy beliefs are not well described. We hypothesized that such cognitive style is driven by delusion proneness, a trait phenotype associated with formation of delusion-like beliefs that exists on a continuum in the normal population. To probe this hypothesis, we developed a COVID-19 conspiracy questionnaire (CCQ) and assessed 577 subjects online. Their responses clustered into three factors that included Conspiracy, Distrust and Fear/Action as identified using principal component analysis. We then showed that CCQ (in particular the Conspiracy and Distrust factors) related both to general delusion proneness assessed with Peter’s Delusion Inventory (PDI) as well as resistance to belief update using a Bias Against Disconfirmatory Evidence (BADE) task. Further, linear regression and pathway analyses suggested a specific contribution of BADE to CCQ not directly explained by PDI. Importantly, the main results remained significant when using a truncated version of the PDI where questions on paranoia were removed (in order to avoid circular evidence), and when adjusting for ADHD- and autistic traits (that are known to be substantially related to delusion proneness). Altogether, our results strongly suggest that pandemic-related conspiracy ideation is associated with delusion proneness trait phenotype.
Journal Article
Arrow of time and its reversal on the IBM quantum computer
Uncovering the origin of the “arrow of time” remains a fundamental scientific challenge. Within the framework of statistical physics, this problem was inextricably associated with the Second Law of Thermodynamics, which declares that entropy growth proceeds from the system’s entanglement with the environment. This poses a question of whether it is possible to develop protocols for circumventing the irreversibility of time and if so to practically implement these protocols. Here we show that, while in nature the complex conjugation needed for time reversal may appear exponentially improbable, one can design a quantum algorithm that includes complex conjugation and thus reverses a given quantum state. Using this algorithm on an IBM quantum computer enables us to experimentally demonstrate a backward time dynamics for an electron scattered on a two-level impurity.
Journal Article
The (H2O) Reagent Ion: Mechanism of Increasing the Specificity of Ion Mobility Spectrometry Based Devices for Toxic Substances Detection in the Presence of Alkanes
In toxic substance detection devices based on ion mobility spectrometry with atmospheric pressure chemical ionization, hydrated ammonium
(H
2
O)
n
is increasingly used as a reagent ion instead of the commonly used hydrated hydroxonium H
3
O
+
(H
2
O)
n
ion and ions preceding and accompanying its formation. The use of hydrated ammonium makes it possible to increase the specificity of devices in the presence of such problematic interferences as exhaust gases of internal combustion engines and motor fuel vapors. In this paper, the mechanism of increasing specificity in the presence of alkanes, significantly predominant in these interferences, is justified. In the absence of ammonia, which is used to produce hydrated ammonium, the chemical ionization of alkanes occurs as a result of fast exergonic reactions with ions preceding (
,
,
, H
2
O
+
, and H
3
O
+
) and accompanying (NO
+
and NO
+
(H
2
O)) the formation of hydrated hydroxonium. When ammonia is added, these ions react with it and are almost completely consumed in fast exergonic reactions. Thereby ammonia suppresses the chemical ionization of alkanes by precursor and accompanying ions. The direct chemical ionization of alkanes with the help of hydrated ammonium does not occur due to the endergonicity of the reactions and the almost complete shift of their equilibrium towards the formation of the initial reagents. As a result, the devices do not give false-positive signals when exposed to alkanes. In addition, the devices do not produce false-negative signals when analytes are detected in a mixture with alkanes, since hydrated ammonium is practically not consumed in reactions with alkanes.
Journal Article
Water Consumption and Drip-Irrigation Regimes for Fruit and Berry Seedlings in the Central Non-Chernozem Region
A key issue in the production of fruit and berry seedlings is the improvement of cultivation technologies, including the use of irrigation. In recent years, global agricultural practices have increasingly favored environmentally safe irrigation methods, such as drip irrigation. The objective of this research is to develop scientifically-based irrigation regimes for drip-irrigated seedlings of fruit (plum, cherry, pear, apple) and berry (raspberry) crops under the conditions of the Central Region of the Non-Chernozem zone in Russia. The research was conducted from 2011 to 2022. Field experiments on the cultivation of 1-, 2-, and 3-year-old seedlings were conducted with three replications, with the following pattern: control (no irrigation) and maintaining soil moisture in the root zone within the ranges of 60 to 80%, 70 to 90%, and 80 to 100% of field capacity. The developed drip-irrigation regimes for fruit and berry seedlings shorten the interval between irrigations to an average of 2 to 9 days, with low irrigation rates (averaging 35.3–49.5 m
3
/ha), depending on the preirrigation threshold (60, 70, and 80% of field capacity) and moisture conditions during the growing season. These regimes maintain soil moisture in the root zone within the specified ranges. Under drip irrigation, the main contribution to total water consumption comes from precipitation (64%) and irrigation (24%). Overall water consumption increases with rising cumulative daily temperatures. The highest water consumption intensity occurs in the early stages of the growing season, while by its end, this rate decreases.
Journal Article
Dynamics of Mensuration Indicators in a Forest Pine Plantation Based on Data of the Long-Term Observations
The purpose of the study is to gain insight into the dynamics of the mensuration indicators, such as average height and diameter and the stand basal areas and standing timber stock, of planted pine forest of various initial densities over a 120-year period based on long-term observations on permanent sample plots. The study targets pine plantations on permanent trial plots of the Forest Experimental Station (Moscow). The growth and yield of forest stands planted on permanent plots was compared against tables of the growth course (yield) tables) of fully stocked pine stands in European Russia and yield tables of modal pine stands of European Russia (the southern boreal ecological region as well as zones of mixed and deciduous forests and forest-steppe). The real curves of the dynamics of the stand indicators are located across the entire range of the presented tabular values. The yield tables, however, offer an oversimplified representation of change in the mensuration indicators, which have a nonsteady dynamics in the actual stands over time. The time series (of dynamics) of average heights and diameters, basal areas, and stocks on sample plots are noted to deviate significantly from the yield tables’ data on fully stocked and modal pine forest stands. An alternative to traditional tables can be prognostic models of the dynamics of mensuration indicators with a different starting state of forest stands without strict alignment with the quality (bonitet) basis.
Journal Article
Temperature Effect on the Stability of the Polarized State Created by Local Electric Fields in Strontium Barium Niobate Single Crystals
The stability of ferroelectric domain patterns at the nanoscale has been a topic of much interest for many years. We investigated the relaxation of the polarized state created by application of a local electric field using a conductive tip of a scanning probe microscope for the model uniaxial relaxor system Sr
x
Ba
1−x
Nb
2
O
6
(SBN) in its pure and Ce-doped form. The temporal relaxation of the induced PFM contrast was measured at various temperatures. The average value of the induced contrast decreases during heating for all investigated crystals. Below the freezing temperature the induced state remains stable after an initial relaxation. Above the freezing temperature the induced state is unstable and gradually decays with time. The stability of the induced state is strongly affected by the measuring conditions, so continuous scanning results in a faster decay of the poled domain. The obtained effects are attributed to a decrease of the induced polarization and backswitching of the polarized area under the action of the depolarization field.
Journal Article
Magnetic Fluids Stabilized with Double Layers of Surfactants in Water Reject the Known Models of Rheology and Dipole–Dipole Interaction
Three samples of aqueous magnetic fluids based on magnetite particles stabilized with double layers of surfactants have been synthesized. The samples have been stabilized with lauric and oleic acids, as well as their salts, taken in three different combinations. The viscosity of the synthesized samples has been measured as depending on the concentration, temperature, and shear rate. With increasing temperature, the viscosity of a sample of the fluid stabilized with a double layer of lauric acid does not decrease relative to the viscosity of water, as has been previously observed for classical magnetic fluids, but rather increases. For a sample stabilized with two layers of lauric and oleic acids, the temperature dependence of the relative viscosity is nonmonotonic. The relative viscosity of a sample stabilized with a double layer of oleic acid is actually independent of temperature. To determine the concentrations of the samples, measurements of magnetization curves were carried out followed by their granulometric analysis. It has been found that the dispersity of the samples remains unchanged upon dilution. The initial magnetic susceptibility of the fluid samples has been shown to increase with concentration more slowly than it has been predicted by the modified effective field model. In contrast to the effective field model (and other ones), the coefficient at the quadratic term in the expansion of the initial susceptibility in terms of the Langevin susceptibility has turned out to be significantly lower than 1/3. Thus, new theories of dipole–dipole interparticle interaction must be developed to describe the properties of magnetic fluids stabilized with double layers of surfactants.
Journal Article
Measuring Magnetization Curves of Ferrofluids: Comparison of the Differential Sweep Method and a Vibrating-Sample Magnetometer
A setup design is proposed for measuring magnetization curves by the differential sweep method. On the described setup, a number of magnetization curves were measured for both classical magnetic fluids and samples obtained by their solidification. The measurement results are compared with the results obtained using a vibrating-sample magnetometer. It is shown that the vibrating-sample magnetometer gives significantly lower values compared to the differential method when measuring the magnetization of a magnetic fluid. When measuring the magnetization of a cured magnetic-fluid sample, a complete coincidence of the results obtained by both measurement methods is observed. The discovered phenomenon is explained by the aggregation of particles in the magnetic fluid under the influence of a magnetic field. Estimations of the relative delay in the movement of aggregates are consistent with the observed divergence in the magnetization magnitude.
Journal Article
Scientific-Based Drip Irrigation Regime for Raspberry Plants Cultivated in the Central Part of the Non-Black Earth Region
Raspberry is an important berry crop; its production volumes increase from year to year. To produce high-quality planting material and gain high and stable yields under unstable weather conditions, resource-saving technologies, including drip irrigation, are required. The purpose of this study was to develop a scientific-based drip irrigation regime for raspberry plants cultivated in the central part of the non-Black Earth Region of Russia. A two-factor field experiment was launched in autumn 2019. The first factor (factor A) was the drip irrigation regime; the moisture content in the root layer was maintained in the following ranges: 60–80, 70–90, and 80–100% of the field moisture capacity (FMC). The second factor (factor B) was the raspberry variety: Nagrada or Solnyshko. Drip watering can substantially reduce irrigation water consumption. In the variant involving drip irrigation and moisture content in the root layer maintained in the range of 80–100% of the field moisture capacity, irrigation water savings averaged 65% compared to traditional watering techniques; in the variant involving drip irrigation and moisture content in the root layer maintained in the range of 60–80% FMC, water savings averaged 78%. In addition, local irrigation creates the optimal air and water regime in the soil. In experimental variants involving irrigation, precipitation accounted for the main part of the total water consumption (71–81%); while irrigation water for only 15–22%. In variants with soil moisture maintained at levels exceeding 70% FMC, the stem diameter in seedlings was 20–40% larger compared to the control, the height of seedlings was 40–50% larger, and the yield was twice as much as in the control variant. This makes it possible to recommend such irrigation regimes as optimal ones.
Journal Article