Mechanism Of Movement Research Articles

Isotopic evidence for soil water sources and reciprocal movement in a semi-arid degraded wetland: Implications for wetland restoration

Understanding water dynamics is a prerequisite for the restoration of degraded ecosystems in arid and semiarid regions. In this study, we carried out δD and δ18O analyses of precipitation, unsaturated soil water, overland flow, surface runoff, and groundwater samples from a seasonally flooded wetland in the Momoge National Nature Reserve of the Songnen Plain, Northeast China, to identify the water sources and understand the mechanisms of unsaturated soil water movement. Unsaturated soil water content (W/W%) at every 20 cm along with a soil profile (0–100 cm) was collected during the growing season, and the HYDRUS-1D model was used to simulate temporal-spatial variations. The results showed that the local meteoric water line (δD=5.90δ18O-7.34, R2=0.95) had a smaller slope and intercept than the global meteoric water line because of strong evaporation at our study site under semi-arid climate. The groundwater was partly recharged by local precipitation via overland flow and unsaturated soil water infiltration. Unsaturated soil water was sourced from both precipitation and groundwater with variations at different depths. The upper soil layer at 0–15 cm was mainly sourced from limited precipitation, while the groundwater could move up to a 25 cm layer during the dry period. The unsaturated soil water content increased with soil depth in the top 40 cm, decreased at depths of 40 to 80 cm, and increased again at depths of 80 to 100 cm. The HYDRUS-1D model could simulate the unsaturated soil water dynamics well in the upper (0–40 cm) and lower (80–100 cm) sections, but poorly for depths of 40–80 cm due to the upward and downward flow. The bidirectional unsaturated soil water movement highlights the importance of capillary groundwater for wetland plants with similar climatic or hydrogeological conditions.

Animal Model for Diabetes Co-existing with Metabolic Syndrome

Metabolic syndrome includes diverse disorders together with truncal obesity, dyslipidemia, high blood pressure, and hyperglycemia. The occurrence of metabolic syndrome is growing globally. The unfavorable results of metabolic syndrome have brought on research efforts to broaden new interventions to reduce the weight of the healthcare system. Because of its multifactorial nature, it may be hard to pick out the best experimental version that high-quality represents the pathophysiology of human metabolic syndrome. Many animal models have evolved and been studied to clarify the molecular mechanisms and useful modifications associated with metabolic sicknesses. Properly characterized and clinically applicable experimental models are taken into consideration as crucial tools for testing new pills and information on their molecular foundation, their pathogenesis, and mechanism of movement. In this review, we collate and discuss the various animal models of metabolic syndrome and the suitability of diabetes co-existing with metabolic syndrome animal models for research also be discussed to provide the readers with a comprehensive overview of the selection of the best animal models to meet their research purpose. Keyword:Animal model, Metabolic syndrome, High fat diet, Rat

Conventional and intermittent drying modeling of agricultural products: A review

AbstractThe purpose of this article is to present a discussion about recent technologies applied to processes involving intermittent drying of agricultural products, in addition to verifying the adjustment of mathematical models, both for conventional and intermittent drying, based on recent research in the literature. It was found that new mathematical models are being studied to describe the drying kinetics, one of which is the generalized Lewis model. Regarding intermittent drying, mathematical models are generally based on mass and energy balances. Furthermore, to obtain the mathematical modeling of intermittent drying for intermittent products, some researchers employ the effective diffusivity technique to describe all possible mechanisms of moisture movement, being estimated by Fick's second law of diffusion. Energy savings were also analyzed for different raw materials, ranging from 6% to 75%. It has been shown that the tempering time, and the conditions of the samples under study, affect energy consumption.

Mechanisms of Movement of Mitochondria in the Cell

The balance between fusion and division determines most of the functions of mitochondria, controls their bioenergetic function, mitochondrial turnover, and also protects mitochondrial DNA. The division promotes equal segregation of mitochondria into daughter cells during cell division itself and enhances the distribution of mitochondria along the cytoskeletal pathways. In addition, division can help isolate damaged mitochondrial segments and thus promote autophagy. Fusion provides protein complementation, and equal distribution of metabolites. The movement of mitochondria in the dendrites, axons and perikaryons of neurons is an important aspect of the vital activity of nerve cells. Disorders of mitochondrial fusion, division, and mobility can lead to defects in the functioning of the nervous system, which makes it important to study these processes for improving methods of prevention, diagnosis, and correction of neurological diseases.

Modeling of self-driven directional movement of underwater oil droplets on bio-inspired nano-coated 3D-printed conical models

The contamination of water with oil from industrial processes has become a worldwide problem that requires the development of efficient, reliable and economical separation methods. Inspired by droplet movements on spider silk, we present in this contribution a model of the separation of oil and water that is based on the effect that liquid droplets move on cone-shaped structures, driven by capillary forces. We extend existing models to barrel-shaped oil droplets that move, completely surrounded by water, along suitably shaped filaments and derive the forces acting on the droplets from first principles of physics. By bringing together the results of the theoretical model and the corresponding experiments, the underlying mechanism of the directional movement of droplets in another liquid medium is thoroughly investigated and modeled. The resulting model predicts the dependence of the droplet motion on time and on “system defining” parameters, such as droplet size, viscosity, and dynamic contact angles formed between droplet and filament surface. We expect this work to pave the road for the design and preparation of bionic structures in the field of droplet transport phenomena, which is of great interest in various applications.

Cell-cell interactions and fluctuations in the direction of motility promote directed migration of osteoblasts in direct current electrotaxis.

Under both physiological (development, regeneration) and pathological conditions (cancer metastasis), cells migrate while sensing environmental cues in the form of mechanical, chemical or electrical stimuli. In the case of bone tissue, osteoblast migration is essential in bone regeneration. Although it is known that osteoblasts respond to exogenous electric fields, the underlying mechanism of electrotactic collective movement of human osteoblasts is unclear. Here, we present a computational model that describes the osteoblast cell migration in a direct current electric field as the motion of a collection of active self-propelled particles and takes into account fluctuations in the direction of single-cell migration, finite-range cell-cell interactions, and the interaction of a cell with the external electric field. By comparing this model with in vitro experiments in which human primary osteoblasts are exposed to a direct current electric field of different field strengths, we show that cell-cell interactions and fluctuations in the migration direction promote anode-directed collective migration of osteoblasts.

The structure inference of flocking systems based on the trajectories.

The interaction between the swarm individuals affects the dynamic behavior of the swarm, but it is difficult to obtain directly from outside observation. Therefore, the problem we focus on is inferring the structure of the interactions in the swarm from the individual behavior trajectories. Similar inference problems that existed in network science are named network reconstruction or network inference. It is a fundamental problem pervading research on complex systems. In this paper, a new method, called Motion Trajectory Similarity, is developed for inferring direct interactions from the motion state of individuals in the swarm. It constructs correlations by combining the similarity of the motion trajectories of each cross section of the time series, in which individuals with highly similar motion states are more likely to interact with each other. Experiments on the flocking systems demonstrate that our method can produce a reliable interaction inference and outperform traditional network inference methods. It can withstand a high level of noise and time delay introduced into flocking models, as well as parameter variation in the flocking system, to achieve robust reconstruction. The proposed method provides a new perspective for inferring the interaction structure of a swarm, which helps us to explore the mechanisms of collective movement in swarms and paves the way for developing the flocking models that can be quantified and predicted.

Electroencephalographic and Autonomic Correlates of Imaginary and Real Movements of Legs in Right-Handers and Left-Handers

—Changes in the spectral power (SP) of electroencephalogram (EEG) in the α-band and the heart rate variability (HRV) were studied in subjects with right and left motor dominance profiles during imaginary and real flexion of right and left feet. During the implementation of motor tasks, a pronounced desynchronization of α-rhythm in frontal and central leads and its less significant changes in parietal and occipital zones of both hemispheres were revealed. The peculiarity of right-handers during mental and real leg movements was the variable and asymmetric character of changes in the SP of α-rhythm in the bilateral leads from various cortical areas. In left-handed subjects, when imagining and performing movements, the desynchronization of α-rhythm in different leads had the same severity and there were practically no hemispheric asymmetry in SP. Right-handers had are latively stable vegetative status during the performance of motor tasks, and HRV changes occurred mainly with real leg movements. In left-handers HRV parameters changed more strongly and mainly during mental actions with their feet. Correlations were found between the α-rhythm SP and HRV parameters, depending on the type of movement and the motor dominance profile of subjects. The obtained data reflect the peculiarities of regulation mechanisms of voluntary leg movements and the differences in the vegetative support of motor activity in right-handed and left-handed people.

31EMF Intubatable 3D Printed Airway Manikin: A Feasibility Study for Replicating Real Patient Anatomy

31EMF Intubatable 3D Printed Airway Manikin: A Feasibility Study for Replicating Real Patient Anatomy

ЗАХИСТ МОРСЬКИХ КАНАЛІВ ВІД НАНОСІВ

Seaports of the world, which built in estuaries and bays, are connected to the seas by approach channels. When they crossing shallow water depths (milky water and surf zones), they are subjected to intensive drift by bottom sediments. It is main reason of decreasing of the depths in the channels over time and to reduce the terms between repair dredging works. The wave velocities are the main reason force of movement of bottom sediments. Projections of the velocities of water particles in waves on shallow water are described by various wave theories. Intensity of drifting to deposit due to a number of natural factors: topography of the sea beds; duration and the severity of storms; speeds of currents; types of bottom soils and their physical and mechanical characteristics. In addition, this process is influenced by the design profile of the channels and their planned position to the seaport gates. In the process of engineering studies and scientific support for the design of sea channels, the total volume of sediment flows and their general direction of transit are established, options for the planned location of channels routes, the angles of their slopes as well as options for protecting channels from drifting sediment are considered, taking into account the factors listed above. The analysis of all factors, as well as, the results physical and mathematical modeling allows take optimal design decisions on the location of the routes of sea channels, their dimensions taking into account the specifics of regions. The dimensions of estimated vessels, types of channels and cargo turnover of sea ports in the near future are also taken into account. The main requirements that apply to sea channels in their design are safe navigation of ships, the minimum amount of dredging works, as in the construction process, as well as exploitation. For this reason, the protection of sea channels from drifting by sediments is a very urgent technical problem. This problem was solved on the basis of analysis of existing methods for protection of sea channels in the shallow-water zones of the seas from the bottom sediments by developing a simple and inexpensive method. The mechanism of movement of bottom sediments under the action of wind waves and current was taking into account, when developing this method. The method proposed in this article is based on the principal of operation of a flexible floating breakwater, which patented in the state Ukraine.

INTERPRETATION OF MORPHOLOGICAL PICTURE OBSERVED IN HISTOLOGICAL PREPARATIONS FROM THE POINT THE VIEW OF STEREOLOGY

The study of a biological microobject from the standpoint of three-dimensionality gives more correct and realistic vision. The study material included 8 preparations of the palatine and labial salivary glands of adult human individuals fixed in 4% glutaraldehyde solution in phosphate buffer (pH 7.4). Following pre-fixation, the object was cut into individual slices and fixed in a freshly prepared similar fixator adding 1% calcium chloride solution at 4 °C for 12 hours. The tissue was washed after the fixation and then processed according to the requirements for electron microscopy. Tissues enclosed in epoxy resin were used to obtain semi-thin series of histological sections for further graphic and plastic reconstruction of epithelial components (including tubular) glands. Semi-thin sections were stained with 0.1% toluidine blue in phosphate buffer with different pH (from 5.5 to 8.5). Spiral, corkscrew, tortuous, arched and other forms of biological tubular structures at the microscopic level are no exception and, as our study shows, are natural phenomena along with their rectilinear shape. It can be assumed that the interdependence between the shape of the tubular transport microchannels and the laminar motion of the fluid naturally reflects the elements of curvilinear symmetry and, in particular, its spiral property. Conclusion. Thus, we could assume that the tortuous shape of transport channels of human and animal tissues is a useful stereomorphological device, and their study and three-dimensional modelling is of great scientific interest, in particular, for understanding the mechanism of laminar fluid movement through biological tubes.

Unsupervised Ethograms of a Vulnerable Bird Species: The Red-Footed Falcon in Northern Italy

Behavioral and movement ecology have quickly advanced as a result of the development of biotelemetry devices and analytical techniques. Global positioning system (GPS) transmitters assist scientists in gathering location and movement data at detailed spatial and temporal resolutions. Machine-learning methods can then be applied to GPS data to provide insights into the ecological mechanisms of animal behavior and movements. By means of accurate GPS data-loggers, in 2019, 2020, and 2021, we tracked 8 red-footed falcons at the two largest colonies in Italy. We collected 13,484 GPS points and used recently introduced machine-learning methodology Unsupervised Animal Behaviour Examiner (UABE) to deduce the regular, nested, and hourly ethograms of the tracked individuals. We found clear and significant patterns of the red-footed falcons’ behaviors on monthly, daily, and hourly bases. Our study is a step forward in advancing the knowledge of this threatened species, and provides a baseline assessment of the current behavioral patterns of this red-footed falcon population, with which results of future studies can be compared to detect potential behavioral changes that act as early warnings of increased human disturbance.

68Ga]Ga-Pentixafor and Sodium [18F]Fluoride PET Can Non-Invasively Identify and Monitor the Dynamics of Orthodontic Tooth Movement in Mouse Model.

The cellular and molecular mechanisms of orthodontic tooth movement (OTM) are not yet fully understood, partly due to the lack of dynamical datasets within the same subject. Inflammation and calcification are two main processes during OTM. Given the high sensitivity and specificity of [68Ga]Ga-Pentixafor and Sodium [18F]Fluoride (Na[18F]F) for inflammation and calcification, respectively, the aim of this study is to assess their ability to identify and monitor the dynamics of OTM in an established mouse model. To monitor the processes during OTM in real time, animals were scanned using a small animal PET/CT during week 1, 3, and 5 post-implantation, with [68Ga]Ga-Pentixafor and Na[18F]F. Both tracers showed an increased uptake in the region of interest compared to the control. For [68Ga]Ga-Pentixafor, an increased uptake was observed within the 5-week trial, suggesting the continuous presence of inflammatory markers. Na[18F]F showed an increased uptake during the trial, indicating an intensification of bone remodelling. Interim and end-of-experiment histological assessments visualised increased amounts of chemokine receptor CXCR4 and TRAP-positive cells in the periodontal ligament on the compression side. This approach establishes the first in vivo model for periodontal remodelling during OTM, which efficiently detects and monitors the intricate dynamics of periodontal ligament.

A Study on Inter-Provincial Environmental Pollution Movement in China Based on the Input–Output Method

In China, environmental pollution responsibilities are divided according to administrative regions. However, because of the strong externality of environmental pollution, the movement of environmental pollution undoubtedly increases the complexity of pollution governance. To divide the responsibility of environmental pollution governance in each province, we effectively quantify the unequal relationship between environmental pollution costs and economic benefits in each province to understand the mechanism and characteristics of inter-provincial environmental pollution movement. Based on the regional input–output model and an inventory we compiled of sulfur dioxide(SO2) emissions of air pollutants in 2012, we calculate the implied inter-provincial environmental pollution emissions and economic benefits from trade, based on production and consumption (supply-side and demand-side). In addition, the movement relationship is explored, and the cost and economic value-added indexes of air pollution control are further constructed to provide effective evidence for a reasonable division of responsibility for environmental pollution control. The results show that there are obvious environmental inequities in the regional trade process in each province, indicating that environmental pollution has been moved. Developed provinces have more economic benefits but pay less in the process of trading goods with less-developed provinces due to the advantages of their industrial structure, while the opposite is true for less-developed provinces. Finally, we propose corresponding policy recommendations to change this condition.

Atomic-scale study on particle movement mechanism during silicon substrate cleaning using ReaxFF MD

The cleaning of silicon wafer surfaces in the integrated circuits manufacturing has not yet been studied at the atomic scale, making it difficult to optimize. In this study, the atomistic mechanism of nanoparticle movement during the cleaning process of the substrate after chemical mechanical polishing (CMP) was investigated using ReaxFF reactive molecular dynamics simulations. The redeposition and removal processes of the silica nanoparticles on the Si (100) substrate with different ambient humidity and substrate state were simulated. Results indicated that water generally plays a positive role in cleaning process, preventing the silica nanoparticles from approaching the substrate and promoting the fracture of interfacial chemical bonds, and it also mitigates the substrate damage caused by particle removal. Aqueous H2O2 influences the substrate state by increasing the oxidizability and hydroxylation level of the substrate surface, which changes the interaction force between the substrate and the nanoparticles, thus impacting particle redeposition process. Additionally, the peroxide facilitates the formation of Si–O–Si bonds and inhibits the removal of the nanoparticles. This work provides atomistic insights into the wafer cleaning process, which is of great significance for the solution design.

Nanobots-based advancement in targeted drug delivery and imaging: An update.

Manipulation and targeted navigation of nanobots in complex biological conditions can be achieved by chemical reactions, by applying external forces, and via motile cells. Several studies have applied fuel-based and fuel-free propulsion mechanisms for nanobots movements in environmental sciences and robotics. However, their applications in biomedical sciences are still in the budding phase. Therefore, the current review introduces the fundamentals of different propulsion strategies based on the advantageous features of applied nanomaterials or cellular components. Furthermore, the recent developments reported in various literatures on next-generation nanobots, such as Xenobots with applications of in-vitro and in-vivo drug delivery and imaging were also explored in detail. The challenges and the future prospects are also highlighted with corresponding advantages and limitations of nanobots in biomedical applications. This review concludes that with ever booming research enthusiasm in this field and increasing multidisciplinary cooperation, micro-/nanorobots with intelligence and multifunctions will emerge in the near future, which would have a profound impact on the treatment of diseases.

Calcium in peroxisomes: An essential messenger in an essential cell organelle.

Calcium is a central signal transduction element in biology. Peroxisomes are essential cellular organelles, yet calcium handling in peroxisomes has been contentious. Recent advances show that peroxisomes are part of calcium homeostasis in cardiac myocytes and therefore may contribute to or even shape their calcium-dependent functionality. However, the mechanisms of calcium movement between peroxisomes and other cellular sites and their mediators remain elusive. Here, we review calcium handling in peroxisomes in concert with other organelles and summarize the most recent knowledge on peroxisomal involvement in calcium dynamics with a focus on mammalian cells.

Laboratory experiments and discrete element modeling on the surface failure induced by EPB tunneling: The effects of cutterhead open ratio and relative tunneling depth

This paper presents laboratory tests and high-fidelity numerical simulations to examine the ground failure induced by Earth Pressure Balance (EPB) Shield Tunneling in granular soils. Specifically, we designed and conducted laboratory tests using a reduced-scale EPB Shield Tunnel machine, and built corresponding three-dimensional (3D) discrete-element method (DEM) models to simulate the dynamic excavation process and to gain further understandings of the mechanisms of the ground movement. The study is particularly focused on the combined influences of the cutterhead open ratio and the relative tunnel depth on the ground motions and stress perturbations during the EPB tunneling, which remain understudied in existing studies. The results show that the open ratio of the cutterhead has significant effects on the ground failure in granular soils, especially in cases of relatively shallow tunnels. The larger the open ratio of the cutterhead, the wider the surface and subsurface settlement trough and the greater the soil pressure in the chamber. The pressure distribution in the soil chamber with a larger cutterhead open ratio is significantly more non-linear than that of the case with a smaller cutterhead open ratio. For a given cover-to-diameter ratio (C/D) of the tunnel, the width parameter (k) is generally constant regardless of the depth for the case with a large cutterhead open ratio, especially in the relatively shallow tunnels, while it increases non-linearly with the depth for the case with a small cutterhead open ratio, especially in relatively deep tunnels. Furthermore, soil arching mechanisms are analyzed qualitatively with respect to different cutterhead open ratios and C/Ds. The study demonstrates quantitatively the response of ground surface to the cutterhead open ratios and C/Ds as well as the associated ground failure mechanisms through a combination of laboratory experiments and 3D DEM simulations, providing further insights into the ground behaviors during the dynamic EPB tunneling process.

Evidence of metal migration over concealed gold deposit in loess terrain and its prospecting significance

There is a growing demand for sensitive penetrating geochemical techniques for prospecting transported covered terrains. However, it is difficult to determine whether geochemical anomalies are the result of deep-seated orebodies or lateral transportation. It remains unclear how metal elements migrate through the concealed layer to the surface, which has called into question these methods and limited their use. In this study, we used three approaches, including trace element patterns, isotope tracers, and microscopic observations, to provide evidence of metal migration over a concealed Au deposit in loess terrain. The results of the survey strongly suggest that the surface ore-forming elements are most likely derived from deep-seated orebodies in the study area. Metal migration to the surface resulted in the accumulation of metals in the surface media. Based on microscopic observations and discussion, we developed a model reflecting the main migration mechanism of metallic nanoparticle movement concerning ascending geogas and migration processes. Additionally, this study demonstrates that fine-fraction soil could be an effective approach for prospecting concealed deposits in loess terrains. We anticipate that this assay will enhance the confidence in using and developing penetrating geochemical techniques and enable them to play a greater role in mineral exploration.

On the mechanism of divergent cable movement: Contribution of the bistable flow activity in the critical flow regime

This paper studies the contribution of the bistable flow activity on the installation of incipient conditions to provoke divergent stayed-cable movement. The experiment consists of performing dynamic tests on a long (6.1 m) and genuine inclined and smooth-surfaced cable in a wind tunnel. The cable has an outer diameter of 0.219 m and is equipped with 128 pressure taps distributed on seven (7) rings. The range of the Reynolds numbers is covering the critical flow regime around a circular cylinder. The evolution of mean and instantaneous aerodynamic coefficients is discussed and Proper Orthogonal Modes of the pressure pattern are created. The results indicate that both transitory regimes in the critical flow regime could contribute to install cable instability incipient conditions. Seemingly, only the unsteady states in the critical flow regime appear to participate on imposing large cable displacement. The influence of the circularity defect on disturbing flow fields around the circular cylinder has also been confirmed. Furthermore, the bistable flow activity has been clearly identified to contribute strongly in the installation of large-amplitude wind-induced vibrations.