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In this paper, the Lidov–Kozai mechanism was studied in the region of the Hilda group and Jupiter Trojans. Asteroids of these populations move in 3:2 and 1:1 orbital resonances with Jupiter. The study was carried out using numerical integration of real asteroids’ equations of motion. A simplified dynamical model was adopted. Perturbations from only Jupiter moving in a fixed elliptical orbit were taken into account. Classical secular perturbations were excluded from osculating elements at every print step, and derived orbital inclinations and eccentricities were plotted versus a perihelion argument ω. As a result, it was found that usual positions of a maximum of the eccentricity and, accordingly, a minimum of the inclination (ω=90∘, 270∘) are shifted in these resonant regions. For Hildas, the maximum of the eccentricity is achieved with perihelion argument values ω=0∘, 180∘. For L4 Trojans, it is achieved with ω=30∘, 210∘, and for L5 Trojans—with ω=150∘, 330∘.

Unprecedented changes in Earth’s water budget and a recent boom in salinity observations prompted the use of long-term salinity trends to fingerprint the amount of freshwater entering and leaving the oceans (the ocean water cycle). Here changes in the ocean water cycle in the past two decades are examined to evaluate whether the rain-gauge notion can be extended to shorter time scales. Using a novel framework it is demonstrated that there have been persistent changes (defined as significant trends) in both salinity and the ocean water cycle in many ocean regions, including the subtropical gyres in both hemispheres, low latitudes of the tropical Pacific, the North Atlantic Subpolar Gyre, and the Arctic Ocean. On average, the ocean water cycle has amplified by approximately 5%since 1993, but strong regional variations exist (as well as dependency on the surface freshwater flux products chosen). Despite an intensified ocean water cycle in the last two decades, changes in surface salinity do not follow expected patterns of amplified salinity contrasts, challenging the perception that if it rains more the seas always get fresher and if it evaporates more the seas always get saltier. These findings imply a time of emergence of anthropogenic hydrological signals shorter in surface freshwater fluxes than in surface salinity and point to the importance of ocean circulation, salt transports, and natural climate variability in shaping patterns of decadal change in surface salinity. Therefore, the use of salinity measurements in conjunction with ocean salt fluxes can provide a more meaningful way of fingerprinting changes in the global water cycle on decadal time scales.

Photosynthetic electron transport rates in higher plants and green algae are light-saturated at approximately one quarter of full sunlight intensity. This is due to the large optical cross section of plant light harvesting antenna complexes which capture photons at a rate nearly 10-fold faster than the rate-limiting step in electron transport. As a result, 75% of the light captured at full sunlight intensities is reradiated as heat or fluorescence. Previously, it has been demonstrated that reductions in the optical cross-section of the light-harvesting antenna can lead to substantial improvements in algal photosynthetic rates and biomass yield. By surveying a range of light harvesting antenna sizes achieved by reduction in chlorophyll b levels, we have determined that there is an optimal light-harvesting antenna size that results in the greatest whole plant photosynthetic performance. We also uncover a sharp transition point where further reductions or increases in antenna size reduce photosynthetic efficiency, tolerance to light stress, and impact thylakoid membrane architecture. Plants with optimized antenna sizes are shown to perform well not only in controlled greenhouse conditions, but also in the field achieving a 40% increase in biomass yield.

Multifunctional activity of the PDX1 gene product is reviewed. The PDX1 protein is unique in that being expressed exclusively in the pancreas it exhibits various functional activities in this organ both during embryonic development and during induction and progression of pancreatic cancer. Hence, PDX1 belongs to the family of master regulators with multiple and often antagonistic functions.

Insights about climate are being uncovered thanks to improved capacities to observe ocean salinity, an essential climate variable. However, cracks are beginning to appear in the ocean observing system that require prompt attention if we are to maintain the existing, hard-won capacity into the near future.

Three likely scenarios of debris flow development in the valley of the Gerkhozhan-Su river are discussed: (I) the passage of a debris flow comparable with that in 2017; (II) a shift of Buzulgan rockslide and the formation of a rock-dammed lake with a dam 20 m high; (III) a catastrophic shift with the formation of a lake with a dam 40 m high. The characteristics of the flow in the area of potential debris flow site were calculated with the use of Yu.B. Vinogradov model of transport–shift debris flow formation. The horizontal distribution of flow velocity and depth in the valley was evaluated with the use of FLO-2D two-dimensional hydrodynamic model with different debris flow parameters. The sources of hydrological data were the hydrographs of debris flow waves derived from transport-shift model. The data on the relief for the transport-shift and hydrodynamic models were derived from processing images from an unmanned flying vehicle obtained by the authors during a reconnaissance study of the debris flow a month after its anomalous shift. The characteristics calculated under each scenario included the debris flow discharges at its source and at the head of the debris cone, flow density, and the spatial distribution of flow rate and depth. The maximal debris flow discharges at the head of the debris cone was 1203 for scenario I, 1662 for scenario II, and 3743 m 3 /s for scenario III. Under all scenarios, the debris flow will overflow over flume sides and inundation of a considerable part of Tyrnyauz Town.

The annual exchange of water between the continents and oceans is observed by GPS, gravimetry, and altimetry. However, the global average amplitude of this annual cycle (observed amplitude of ∼8 mm) is not representative of the effects that would be observed at individual tide gauges or at ocean bottom pressure recorders because of self‐attraction and loading effects (SAL). In this paper, we examine the spatial variation of sea level change caused by the three main components that load the Earth and contribute to the water cycle: hydrology (including snow), the atmosphere, and the dynamic ocean. The SAL effects cause annual amplitudes at tide gauges (modeled here with a global average of ∼9 mm) to vary from less than 2 mm to more than 18 mm. We find a variance reduction (global average of 3 to 4%) after removing the modeled time series from a global set of tide gauges. We conclude that SAL effects are significant in places (e.g., the south central Pacific and coastal regions in Southeast Asia and west central Africa) and should be considered when interpreting these data sets and using them to constrain ocean circulation models.

Debris flows are one of the most dangerous and common hydrological phenomena in mountainous regions. They are extremely various in their type and character, but they are always mountain flows consisting of a mixture of water and loose-fragmental debris. The problem of calculation and forecasting the mudflows still remains intractable. There are several reasons for that: Firstly, the representatives of the whole spectrum of the Earth Sciences (Hydrology, Geology, Geomorphology, Geography, Mechanics, Rheology) deal with this problem from their point of view. Secondly, systematic monitoring of passing debris flows are currently held only in several countries only (USA, Canada, Austria, Switzerland, Japan, China), because they require significant funding. Thirdly, the calculation methods, having been accepted for the present time, give certain errors. In this article, the results of the artificially triggered debris flow experiments conducted in 1972–1976 in the Chemolgan river basin, organized by the Kazakh Research Hydrometeorological Institute are described. These were the first full-scale experiments with the detailed recording of the numerous debris flows characteristics ever conducted. The movie is attached as supplementary material to the Editorial of the Special Issue. The information about the used measurement equipment, the obtained characteristics of debris flows, the debris flow classification accepted as a result of the experiments is given. Conducting such experiments in nature allowed us to assess various aspects of the formation of these natural phenomena and made it possible to build the mathematical models of the debris flow processes.

AbstractThe results of a study of sensors based on thin semiconductor films of CdxPb1 – xS solid solutions intended for the determination of nitrogen dioxide in air are described. For a comparative assessment of the composition, morphology, and functional properties of the films, they were synthesized from reaction mixtures containing various cadmium salts. It was found that the maximum response is provided by layers obtained using cadmium acetate, in which the composition of the solid solution differs in the maximum supersaturation level in CdS. The films were formed of crystallites with average sizes of ~200 nm. When the concentration of nitrogen dioxide in air was 0.05‒200 mg/m3, the relative change in the ohmic resistance of sensors ranged from 8 to 80%. It was shown that the threshold concentration of NO2 in air was about 0.02 mg/m3. The reversible nature of the gas adsorption process opens a possibility for the creation of reusable chemical sensors based on CdxPb1 – xS films, differing in a relatively low threshold concentration of NO2 detection and selective response in the presence of significantly higher concentrations of O2, CO2, and H2.

The oceanic response to surface loading, such as that related to atmospheric pressure, freshwater exchange, and changes in the gravity field, is essential to our understanding of sea level variability. In particular, so-called self-attraction and loading (SAL) effects caused by the redistribution of mass within the land–atmosphere–ocean system can have a measurable impact on sea level. In this study, the nature of SAL-induced variability in sea level is examined in terms of its equilibrium (static) and nonequilibrium (dynamic) components, using a general circulation model that implicitly includes the physics of SAL. The additional SAL forcing is derived by decomposing ocean mass anomalies into spherical harmonics and then applying Love numbers to infer associated crustal displacements and gravitational shifts. This implementation of SAL physics incurs only a relatively small computational cost. Effects of SAL on sea level amount to about 10% of the applied surface loading on average but depend strongly on location. The dynamic component exhibits large-scale basinwide patterns, with considerable contributions from subweekly time scales. Departures from equilibrium decrease toward longer time scales but are not totally negligible in many places. Ocean modeling studies should benefit from using a dynamical implementation of SAL as used here.