Density Disturbances Research Articles

X‐Raying Neutral Density Disturbances in the Mesosphere and Lower Thermosphere Induced by the 2022 Hunga‐Tonga Volcano Eruption‐Explosion

AbstractWe present X‐ray observations of the upper atmospheric density disturbance caused by the explosive eruption of the Hunga Tonga‐Hunga Ha'apai (HTHH) volcano on 15 January 2022. From 14 January to 16 January, the Chinese X‐ray astronomy satellite, Insight‐HXMT, was observing the supernova remnant Cassiopeia A. The X‐ray data obtained during Earth's atmospheric occultations allowed us to measure neutral densities in the altitude range of 90–150 km. The density profiles above 110 km altitude obtained before the major eruption are in reasonable agreement with expectations by both GAIA and NRLMSIS 2.0 models. In contrast, after the HTHH eruption, a severe density depletion was found up to 1,000 km away from the epicenter, and a relatively weak depletion extending up to km for over 8 hr after the eruption. In addition, density profiles showed wavy structures with a typical length scale of either 20 km (vertical) or 1,000 km (horizontal). This may be caused by Lamb waves or gravity waves triggered by the volcanic eruption.

Flexible migration by woodland caribou in Ontario, Canada

AbstractRecent studies of ungulate movement ecology suggest that seasonal movement tactics often vary within a population. The forest‐tundra and forest‐dwelling ecotypes of woodland caribou (Rangifer tarandus caribou) in Ontario, Canada, are traditionally presumed to differ in migratory strategy; however, their potential for facultative migration, the practice of interannual switching between migratory and non‐migratory strategies, has yet to be explored. Understanding facultative migration, and any inherent variation and influences could help improve habitat management. We acquired global positioning system (GPS) telemetry‐based movement data from 109 radio‐collared caribou across the Hudson Bay lowlands between 2009 and 2019. We compared the data with estimates of vegetation density, snow cover, and human disturbance to identify environmental influences associated with the probability and magnitude of migration. We also compared seasonal resource selection between migratory and sedentary individuals. Caribou demonstrated plasticity in migration, with evidence of facultative migration by the forest‐tundra and the forest‐dwelling ecotypes. Variation in migration was likely a combination of local adaptation and acute response to changing environmental factors, particularly snow. Probability and distance of migration were positively correlated with snow, while distance also showed spatial dependency. Plasticity in migration has significant implications in relation to future shifts in climate and should be considered in relevant predictive analyses.

STATISTICAL CHARACTERISTICS OF THE GEOPHYSICAL FIELDS DISTURBED BY WEATHER FRONTS

The Earth (internal spheres) — atmosphere — ionosphere — magnetosphere (EAIM) formation is a single integrated system with direct and reverse, positive and negative coupling, as well as with their combination. The high-energy sources of natural and anthropogenic origins activate coupling between the components of the EAIM. The effects that the sources of various physi- cal nature have on the EAIM system have been studied quite well, while the influence of the weather fronts and other powerful atmospheric sources on the EAIM system and its components has been studied only partly. The scientific objective of this study is to conduct a statistical analysis of variations in the basic parameters of the geophysical fields that accompany the movement of atmospheric fronts. The histograms have been constructed that show the atmospheric pressure difference, atmospheric tem- perature difference, duration of the action of the atmospheric front, and the rate of change in the pressure and temperature, as well as the histograms showing the distribution of variations in the atmospheric electric field, the atmospheric current density, and in the magnetic field. The analysis undertaken has shown that these parameters exhibit variations within a broad range of values. The mean values of these parameters are estimated to be 145 Pa, 6 °C, 70 min, 2.4 Pa/min, 0.23 °C/min, 3.2 kV/m, 63 nA/m2, and 20 nT, respectively. The analysis of the scatter diagrams shows that the correlation between the variation in physi- cal parameters is almost always absent. This means that a single governing parameter along the path of the atmospheric front does not exi st. A simplified analytical relation has been derived to estimate the perturbation in the electric field strength caused by the atmospheric front, which yields ~6–60 kV/m values that increase by an order of magnitude during thunderstorms. Under disturbed conditions, the atmospheric current density is shown to increase from 10 –12 A/m2 to 10–11—10–10 A/m 2. The fol- lowing three mechanisms of an increase in the magnetic induction under the influence of the atmospheric front are considered: the disturbances of the external current density, electromagnetic induction, and the magnetic effect of turbulence. All these mechanisms yield the value of the effect less than ~1 nT. Only the magnetic effect of the ionosphere can explain an increase of 10—70 nT in the magnetic field variations. The energetics of the pressure, temperature, electric, and magnetic fields has been estimated to be (~10 16—10 17 J, ~1013—1014 W), (~1018—1019 J, 1015—1016 W), (~109—1011 J, ~106—108 W), (~1010 — 10 11 J, 107—108 W), respectively. The following channels have been validated through which the components of the EAIM sys- tem couple under the action of atmospheric fronts: atmospheric pressure differences, ionospheric electron density differences, the generation of infrasound and gravity waves, the generation of electromagnetic waves by lightning flashes, and the perturba- tions in the global electric circuit.

An Index Description of the General Characteristics of Thermospheric Density Based on the Two‐Line‐Element Data Sets and the Spectral Whitening Method

AbstractThe thermospheric density and its variations are crucial to aerospace activities as well as space weather research and operation. However, due to the difficulties in observing the thermosphere, there has been a lack of effective descriptions for the general characteristics of thermospheric density. In this paper, the Two‐Line‐Element data sets (TLEs) from multi‐target low Earth orbit satellites are used to derive a proxy of the daily average atmospheric density in the thermospheric shell located in the vicinity of LEOs' orbital altitude. It captures the overall characteristics of the thermosphere and exhibits good correlations (∼0.9) with modeled and observed thermospheric density. By applying the spectral whitening method to this proxy, a new index is derived to describe non‐periodic perturbation of the density where the specific satellite passed by. The fact that the obtained from different satellites within the same thermospheric shell presents significant consistency to each other means that the new index is a good indicator for the overall feature of the variations of thermospheric density, and it is possible to define a unified regional index to describe density disturbances for the thermospheric shell where these satellites fly through. Moreover, the at different altitudes also present good consistency suggesting the possibility of defining a global index , capable of describing the density variation of the entire thermosphere.

Spatial Structure of Plasma Density Disturbances in the Topside Ionosphere Caused by High-Power HF Heating of the F2 Layer

Spatial Structure of Plasma Density Disturbances in the Topside Ionosphere Caused by High-Power HF Heating of the F2 Layer

Demography, Structure, and Composition of a Low-Disturbance Forest in Luzon, Philippines

Tropical forests continue to face deforestation in countries such as the Philippines. To look at the long-term behavior of forests in response to intrinsic and extrinsic factors, continual monitoring of forest dynamics is needed. To do this, we established a 2-ha permanent tropical forest plot in a low-disturbance area in Maluyon, Philippines. We addressed three main questions: 1) How does the plot change through time? 2) How do different species in the plot change through time? 3) Would the responses differ by tree size? We measured, mapped, and identified all trees >1 cm in diameter in 2011. In 2015, we re-measured surviving trees and measured, mapped, and identified recruits. A total of 177 tree species were found in the plot. The forest exhibited a mean growth rate of 0.054 cm/year, mortality rate of 0.011%/year, and recruitment rate of 0.019%/year. Overall growth and mortality rates were lower in Maluyon than in other plots, possibly due to the forest’s high tree density and low disturbance. Species-specific rates revealed the presence of both the growth-survival and the stature-recruitment trade-offs. Size class analysis showed higher growth rates in large-sized than in small-sized trees. In contrast, small-sized trees exhibited a higher mortality rate compared to large-sized trees, likely due to density dependence. Key findings of the study may be utilized to increase the success rate of restoration efforts in this watershed. Using a mix of fast-growing, generalist species with high survival rates (e.g., Allophyllus cobbe and Anisoptera thurifera) is highly recommended.

Increased power capture efficiency of large-scale wind turbines using model-free coordinated pitch, yaw, and torque control with wind direction estimation in diverse environmental conditions

Offshore large-scale wind turbine systems (LSWTS) face challenges in pitch and yaw management mainly due to unreliable wind direction measurements, delayed responses, and redundant yaw movements, reducing their optimal efficiency under various offshore renewable environmental conditions. To address this problem and increase power capture, this study introduces a model-free coordinated super-twisting pitch, yaw, and generator torque control for LSWTS under various wind speed and direction conditions. To achieve this, a dynamic model of the weather vane is first designed to accurately measure the wind directions under fluctuating wind speed and environmental conditions. At the same time, the onshore/offshore LSWTS weather vane model is formulated to operate under optimal conditions considering air density, temperature, humidity, and external disturbances. Then, super-twisting control based on an enhanced adaptive barrier function is proposed for the coordinated control operation of the pitch, yaw, and generator torque actuators for stable maximum power extraction of the offshore LSWTS. Finally, simulation and comparative studies are presented to signify the increased power capture ability of the proposed scheme for both a 4.8 MW benchmark and a 20 MW PMVG-based offshore LSWTS to verify robustness against wind gusts, direction changes, and model uncertainties.

Quantitative asymptotic stability of the quasi-linearly stratified densities in the IPM equation with the sharp decay rates

We analyze the asymptotic stability of the quasi-linearly stratified densities in the 2D inviscid incompressible porous medium equation on R2 with respect to the buoyancy frequency N. Our target density of stratification is the sum of the large background linear profile with its slope N and the small perturbation that could be both non-linear and non-monotone. Quantification in N will be performed not only on how large the initial density disturbance is allowed to be but also on how much the target densities can deviate from the purely linear density stratification without losing their stability.For the purely linear density stratification, our method robustly applies to the three fundamental domains R2, T2, and T×[−1,1], improving both the previous result by Elgindi (2017) [18] on R2 and T2, and the study by Castro et al. (2019) [12] on T×[−1,1]. The obtained temporal decay rates to the stratified density on R2 and to the newly found asymptotic density profiles on T2 and T×[−1,1] are all sharp, fully realizing the level of the linearized system. We require the initial disturbance to be small in Hm for any integer m≥4, which we even relax to any positive number m>3 via a suitable anisotropic commutator estimate.

Solar Wind Plasma Parameters in Relation with Good Quality Magnetic Cloud Related Geomagnetic Storms

We have analyzed magnetic cloud related geomagnetic storms detected during the period of solar cycle 23 and 24 with disturbances in solar wind plasma parameters. We have observed that all the MC related geomagnetic storms are accompanying with disturbances in solar wind plasma parameters. The magnitude of magnetic cloud related geomagnetic storms is soundly correlated with peak disturbances values of solar wind plasma parameters solar wind plasma velocity (SWPV), solar wind plasma density (SWPD), solar wind plasma temperature (SWPT), interplanetary magnetic fields (IMFB) and southward component of interplanetary magnetic fields (IMFBz). Large positive correlation with correlation coefficient 0.60 have found between magnitude of MC related GMS and peak value of related disturbances in IMFB and 0.67 between magnitude of MC related geomagnetic storms and peak value of associated disturbances in IMFBz. Additionally positive correlations with correlation coefficient 0.54 have been found between magnitude of MC related GMS and peak value of associated disturbances in solar wind plasma temperature ,0.40 between magnitude of MC related GMS and peak value of associated disturbances in solar wind plasma velocity, 0.27 between magnitude of MC related geomagnetic storms and peak value of disturbances in soar wind plasma density.

Using soundscape to monitor population size, demographics, and antipredator behavior in a dense aggregation of colonial seabirds

Migratory seabirds are vulnerable to decline due to climate change and anthropogenic disturbances. Common terns (Sterna hirundo) are highly vocal colonial seabirds that serve as bioindicators of their foraging grounds throughout their migratory range. Historically, monitoring colonial seabirds is invasive and time-consuming, and traditional acoustic approaches are complicated by high amounts of call overlap. Monitoring the behavioral ramifications of disturbance, as well as overall colony size and health, is crucial to implementing effective management decisions. However, methods are needed to do so efficiently and with minimal disturbance. In this study, we demonstrate that population size, demographics, and behavior can be assessed acoustically through changes in acoustic energy across varying temporal scales. To do this, we compared acoustic energy to in-person observations of nest density, chick-hatching, and investigator disturbance. We found that trends in acoustic energy align with observations of nest density, and the distribution of acoustic energy across frequency bands is indicative of colony demographics. Furthermore, we found a significant relationship between acoustic energy and investigator disturbance within 20 meters of an acoustic recorder. Overall, our findings suggest that colony-wide trends in population size, demographics, and behavior can be monitored via acoustic energy without the time-consuming analysis of individual calls.

Drivers of functional diversity in small-bodied mammals across a deforestation frontier in the Southern Brazilian Amazon

Deforestation remains the most pervasive driver of biodiversity erosion across tropical forests. Understanding how species can cope with such habitat changes is particularly important along the rapidly expanding agricultural frontiers. To do so, we used a functional perspective examining small mammal responses to habitat loss, fragmentation, and degradation across the ‘Arc of Deforestation’ in the Southern Brazilian Amazon. Small mammals were surveyed using a combination of conventional and pitfall traps across 20 forest fragments—ranging from 42 to 4743 ha—in addition to two relatively continuous forest sites (> 7000 ha). These fragments lie isolated by a cattle pasture matrix of varying grazing intensity. We then analysed taxonomic and functional diversity patterns—represented by Simpson Diversity and Rao Quadratic entropy indices—in Generalised Linear Models containing local- to landscape-scale predictors of variation. Further, we used a functional trait composition approach based on community-weighted mean trait values to depict and predict small mammal functional variations across this degradation gradient. From a total of 847 individuals recorded belonging to 24 taxa, functional responses tended to follow the taxonomic diversity, both increasing with fragment area. The functional dimension further was promoted by low fire-related disturbance. Functional trait composition was mainly driven by habitat quality, represented by tree density, arthropod biomass, and fire-related disturbance. Our results reinforce that small forest fragments sustain depauperate small mammal assemblages both taxonomically and functionally. Accounting for habitat quality further allows for boosting the persistence across functional groups. Our findings can be used to improve the efficiency of management practices thereby maximising the multiple dimensions of small mammal diversity and their associated ecosystem services across tropical deforestation frontiers.

Assessment of Retinal Microangiopathy in Patients with Balkan Endemic Nephropathy Using Optical Coherence Tomography Angiography-A Pilot Study.

Background and Objectives: It is well known that alterations in microvascular structure and function contribute to the development of ocular, renal, and cardiovascular diseases. Accordingly, the presence of fundus vascular changes in patients suffering from chronic kidney disease (CKD) and Balkan endemic nephropathy (BEN) may provide information of prognostic value regarding the progression of renal disease. This study aimed to examine the associations between clinical characteristics and retinal optical coherence tomography angiography (OCTA) parameters in patients with BEN and compare them with those in CKD. Materials and Methods: This pilot study, conducted from March 2021 to April 2022, included 63 patients who were divided into two groups: the first group consisted of 29 patients suffering from BEN, and the second was a control group of 34 patients with CKD. Demographic, laboratory, clinical, and medication data were noted for all the patients included in this study. Each eye underwent OCT angiography, and the results were interpreted in accordance with the practical guide for the interpretation of OCTA findings. Results: Statistically significantly higher levels of total serum protein and triglycerides were recorded in the BEN group than in the CKD group, while the level of HDL cholesterol was lower. Based on the performed urinalysis, statistically significantly higher values of total protein and creatinine were detected in patients with CKD compared to the BEN group. It was demonstrated that the OCTA vascular plexus density of certain parts of the retina was in significant association with systolic and diastolic blood pressure, creatinine clearance, urinary creatinine, total cholesterol, diabetes mellitus type 2, age, body mass index, total serum and urinary protein, sCRP, and diuretic and antihypertensive treatment. Conclusions: In comparison with CKD, BEN leads to more significant disturbances in retinal vasculature density.

Polystyrene microplastics induced disturbances in neuronal arborization and dendritic spine density in mice prefrontal cortex

An increasing use of plastics in daily life leads to the accumulation of microplastics (MPs) in the environment, posing a serious threat to the ecosystem, including humans. It has been reported that MPs cause neurotoxicity, but the deleterious effect of polystyrene (PS) MPs on neuronal cytoarchitectural morphology in the prefrontal cortex (PFC) region of mice brain remains to be established. In the present study, Swiss albino male mice were orally exposed to 0.1, 1, and 10 ppm PS-MPs for 28 days. After exposure, we found a significant accumulation of PS-MPs with a decreased number of Nissl bodies in the PFC region of the entire treated group compared to the control. Morphometric analysis in the PFC neurons using Golgi-Cox staining accompanied by Sholl analysis showed a significant reduction in basal dendritic length, dendritic intersections, nodes, and number of intersections at seventh branch order in PFC neurons of 1 ppm treated PS-MPs. In neurons of 0.1 ppm treated mice, we found only decrease in the number of intersections at the seventh branch order. While 10 ppm treated neurons decreased in basal dendritic length, dendritic intersections, followed by the number of intersections at the third and seventh branch order were observed. As well, spine density on the apical secondary branches along with mRNA level of BDNF was significantly reduced in all the PS-MPs treated PFC neurons, mainly at 1 ppm versus control. These results suggest that PS-MPs exposure affects overall basal neuronal arborization, with the highest levels at 1 and 10 ppm, followed by 0.1 ppm treated neurons, which may be related to the down-regulation of BDNF expression in PFC.

The Effect of Disturbances on Plant-Model Mismatch Detection using the Plant-Model Ratio: A Surge Tank Case Study

The surge tank in a bulk tailings treatment plant aims to reject flow and density disturbances. However, for large disturbances, there may be an inversion in the gain between the water inflow and tank slurry density for a linearized model of the plant. The plant-model ratio (PMR) is a method to diagnose model-plant mismatch (MPM), such as gain-inversion, in the absence of disturbances. This article evaluates the influence of disturbances on the ability of the PMR to diagnose MPM for the surge tank. If the disturbance is measured, as in the case of the surge tank, the PMR is able to detect MPM such as gain-inversion. A controller can be adapted according to the MPM information from the PMR diagnosis.

Fine-tuned local coordination environment of Pt-N in nanocarbons for efficient propane dehydrogenation.

Based on the disturbance of electronic density, nitrogen-doped nanocarbons show promising properties to anchor metal clusters. However, precisely regulating the coordination mode between N species and the active site remains challenging. Herein, we rationally designed three N types (graphitic N, pyridinic N and pyrrolic N) in nanocarbons to anchor Pt clusters for the benchmark propane dehydrogenation. The specific activity of the pyridinic-N-doped catalyst was 147.54 molC3H6 molPt-1 h-1 at 550 °C, which was 1.3 times higher than those of graphitic- and pyrrolic-N-doped catalysts. Unlike the regular tetrahedron Pt cluster in the graphitic-N catalyst or the distorted three-layered Pt cluster in the pyrrolic-N catalyst, the Pt cluster in the pyridinic-N catalyst was an inverted tetrahedron, which increased the contact degree without geometric repulsion towards C-H bond scission. The geometric parameters of detached H and C atoms in the methylene group for the pyridinic N catalyst was decreased to strengthen the C-H bond scission. After CH3CHCH3* adsorption, the Bader charge of the Pt active site also became highly positive, which tailored the d-band center closer to the Fermi level and provided more vacant orbitals for C-H bond breakage. Therefore, pyridinic N in nanocarbons is promising to anchor small-sized Pt for alkane dehydrogenation in terms of geometric and electronic effects.

Observations and simulations of large-scale traveling ionospheric disturbances during the January 14-15, 2022 geomagnetic storm

Using the total electron content (TEC) observations from GPS, and simulations from the Thermosphere Ionosphere Electrodynamic General Circulation Model (TIEGCM), this work investigates the large-scale traveling ionospheric disturbances (LSTIDs) and the possible involved drivers during the geomagnetic storm on January 14-15, 2022. Based on the term analysis of O+ continuity equation in TIEGCM, it is found that the traveling atmospheric disturbances in equatorward winds are responsible for the LSTIDs, with minor contributions from plasma drifts owing to the prompt penetration electric field. A strong interhemispheric asymmetry of the LSTIDs is observed, which might be attributed to both the equatorward wind disturbances and background plasma. The stronger wind (plasma) disturbances occurs in the winter hemisphere than that in the summer hemisphere. The maximum magnitude of LSTIDs in electron density disturbances occurs at ∼250 and ∼270 km in the northern and southern hemispheres, respectively, owing to both the thermospheric equatorward winds and background plasma. An interesting phenomenon that tail-like LSTIDs occur at the dip equator and low latitudes might be related to the eruption of the Tonga volcano, but it is not well reproduced in TIEGCM that deserves further exploration in a future study.

THE CORRELATION OF SHORT-PERIOD WAVE DISTURBANCES IN THE PEAK ELECTRON DENSITY OF THE F2 LAYER AND THE TOTAL ELECTRON CONTENT (TEC) IN THE IONOSPHERE

Using data of the vertical sounding ionosonde and the GNSS receiver operating in Irkutsk, we analyzed the correlation of short-period (periods less than 24 hours) wave disturbances of the peak electron density of the F2 layer (NmF2) and the total electron content (TEC) in the ionosphere. The measurement data for the period 2003–2020, which included almost two solar cycles, were processed. It has been established that the most probable case is a high positive correlation of short-period disturbances of NmF2 and TEC. With the growth of solar and geomagnetic activity, the number of cases of strong positive correlation increases (from 53% to 66%) and the number of cases of both positive and negative weak correlation decreases (from 46% to 33%). During powerful geomagnetic storms, the highest correlation (up to R = 0.89) is observed in the storm main phase and then decreases in the recovery phase up to negative R values. Possible physical mechanisms of the obtained results are considered.

Statistical Relationship of Ionospheric Disturbances Caused by Typhoon Extinction on the Sea

AbstractBased on the data of magnetic field and electronic density of SWARM, and Total Electron Content, this paper screened six typhoons that died out on the sea. We studied how typhoons affected the ionosphere when they died out without the influence of topography and other factors. The statistical results show that during the extinction of typhoons, the magnetic disturbances all appeared, and the electron density disturbances were observed in five typhoons. The frequency of the electronic density disturbance is slightly higher than the magnetic disturbance. The range of the electronic density disturbance is mostly five or six hundred kilometers and relatively concentrated. The range of the magnetic disturbance can reach about two thousand kilometers and is relatively scattered. Our results indicate that the extinction of typhoon may affect the ionosphere through acoustic gravity waves (AGWs). The AGWs is not generated by friction, but may be from the typhoon itself or a new phenomenon when the typhoon dies out.

Склеростин-залежні механізми формування остеопорозу у хворих цукровим діабетом 2 типу та ожирінням

при обстеженні 103 пацієнтів на цукровий діабет 2 типу (ЦД), що у 83 випадкахперебігав на тлі збільшеної маси тіла або ожиріння, було встановлено вірогідне збільшеннявмісту склеростину у сироватці крові, яке мало пряму кореляційну залежність з індексоммаси тіла. Висловлено припущення, що зміни даного глікопротеїну, який входить до групиантагоністів кісткових морфогенетичних білків, відбуваються внаслідок багатьох процесів ворганізмі: збільшення синтезу ФНП-α адипоцитами, ендотелієм судин, клітинами нейроглії натлі пре- та менопаузи, що сприяє порушенню мінеральної щільності кісткової тканини, тобтоформуванню остеопорозу. Ендокринний остеопороз становить найбільшу групу вторинногоостеопорозу, провідною причиною якого є цукровий діабет 2 типу. В разі наявності ЦД 2 типу,який перебігає на тлі ожиріння, формуються умови до розвитку остеопоротичних станів, одниміз механізмів розвитку яких може виступати глікопротеїн склеростин. Метою дослідженнястало визначення структурно-функціонального стану кісткової тканини шляхом дослідженнявмісту склеростину у хворих на цукровий діабет 2 типу, що перебігає на тлі топографічнихособливостей розподілу жирової тканини. До роботи було залучено 103 хворих на ЦД 2 типу,який у 83 випадках перебігав в поєднанні з надлишковою вагою або ожирінням (основна група). Догрупи порівняння увійшло 20 хворих на ЦД 2 типу, що був діагностований у пацієнтів з незмінениміндексом маси тіла (ІМТ). Вік хворих коливався від 31 до 55 років та в середньому по групах складав43±4,6 років та 44,1±2,1 роки відповідно. В обох групах хворих переважали чоловіки 44 (53%) та11 (55%) осіб. Тривалість захворювання реєструвалась в межах від 1 до 13 років. Визначеннярозподілу жирової тканини в організмі досліджували за допомогою ваг для характеристикискладу тіла - OMRON BF511 (Японія). Ідентифікували вміст вісцеральної жирової тканини(ВЖТ) та підшкірної жирової тканини (ПЖТ). Активність склеростину в сироватці крові
 визначали імуноферментним методом з використанням комерційних тест-систем «Biomedi-ca» (США) згідно інструкції на імуноферментному аналізаторі «Labline-90» (Австрія). Обробку
 отриманих даних здійснювали методом варіаційної статистики за допомогою ліцензійногопрограмного забезпечення Stata 10 («StatSoft Inc.», США). Перевірка на нормальність розподілуданих виконувалася за допомогою критерію Шапіро-Уілка. Для параметрів з нормальнимрозподілом розраховували середню величину (M) ± стандартну помилку середньої (m). Отриманірезультати розглядалися як статистично значущі при p<0,05. В результаті було визначено, щозбільшення ІМТ супроводжувалось підвищенням показника склеростину. Тобто, виявлені зміниглікопротеїну, який входить до групи антагоністів кісткових морфогенетичних білків, дають змогу припустити порушення процесу диференціації остеобластів. Тобто, як ЦД 2 типу, такі кількісна зміна жирової тканини з її перерозподілом, негативно впливають на метаболізмкісткової тканини. Так, перебіг цукрового діабету супроводжується збільшенням активностіпрозапальних цитокінів, а саме, ФНП-α – складового цитокінового каскаду жирової тканини.Цей феномен також пов’язують із залученням до процесу судин (ендотеліальні клітинипродукують даний цитокін), нервової тканини (залучення клітин нейроглії) та метаболічнимизсувами в організмі. Окрім того F.Xu та співавт. в експерименті доведено, що остеокластогенезпригнічується при гіперглікемічних та гіперінсулінемічних станах. Тобто, у хворих на ЦД призбільшенні ІМТ складається негативний «тандем» через додаткове надходження з багатьохклітин ФНП-α та збільшення синтезу склеростину, що не тільки «запускає» процес порушеннямінеральної щільності кісткової тканини (МЩКТ), але й підтримує його впродовж всьогоперебігу захворювання. Також певна роль відводиться віковому аспекту обстежених хворихна ЦД (середній вік менопаузи у здорових жінок нашої країни становить 45 років), що такожсприяє пригніченню кісткового метаболізму. В такому разі збільшення активності склеростинув поєднанні з негативним фоном (ожиріння, період менопаузи) можна розглядати як один ізмеханізмів формування остеопоротичних змін. При цьому поєднуються механізми первинного тавторинного ОП, що посилює і прискорює процес порушення архітектоніки кістки. Тому можназробити висновки, що у хворих на цукровий діабет 2 типу у поєднанні з ожирінням виникаютьумови до зниження якості кісткової тканини через уповільнення кісткового метаболізму, щосприяє формуванню остеопоротичних станів.

Simultaneous Global Ionospheric Disturbances Associated With Penetration Electric Fields During Intense and Minor Solar and Geomagnetic Disturbances

AbstractA new observational phenomenon, named Simultaneous Global Ionospheric Density Disturbance (SGD), is identified in GNSS total electron content (TEC) data during periods of three typical geospace disturbances: a Coronal Mass Ejection‐driven severe disturbance event, a high‐speed stream event, and a minor disturbance day with a maximum Kp of 4. SGDs occur frequently on dayside and dawn sectors, with a ∼1% TEC increase. Notably, SGDs can occur under minor solar‐geomagnetic disturbances. SGDs are likely caused by penetration electric fields (PEFs) of solar‐geomagnetic origin, as they are associated with Bz southward, increased auroral AL/AU, and solar wind pressure enhancements. These findings offer new insights into the nature of PEFs and their ionospheric impact while confirming some key earlier results obtained through alternative methods. Importantly, the accessibility of extensive GNSS networks, with at least 6,000 globally distributed receivers for ionospheric research, means that rich PEF information can be acquired, offering researchers numerous opportunities to investigate geospace electrodynamics.