Flow Anomalies Research Articles

Multicompartment Dynamic Contrast Magnetic Resonance Lymphangiography in Diagnosis of Complicated Lymphatic Anomaly.

Background: To describe the dynamic contrast magnetic resonance lymphangiography (DCMRL) findings of three patients with complicated lymphatic anomaly (CLA) and protein losing enteropathy. We further discuss the importance of a multicompartment (intrahepatic [IH], intramesenteric [IM], and intranodal [IN]) DCMRL in delineating central lymphatic flow pathologies. Methods and Results: This is a retrospective study of three patients-one adult and two children who individually underwent the three-compartment DCMRL, namely IN-DCMRL, IH-DCMRL, and IM-DCMCRL. Findings from the results of the DCMRL for these three patients were obtained from the medical records and compared. Using the multicompartment imaging modalities, chylous fluid leakage into the peritoneum was observed using IM-DCMRL and IH-DCMRL but not IN-DCMRL for one of the patients in the case series. In contrast, leakage of chyle into the mediastinum was noted using IN-DCMRL but not IH-DCMRL and IM-DCMRL on another patient in this case series. Conclusion: Owing to the variability in outlining lymphatic flow pathologies, multicompartment imaging gives a more global picture of individual conduction disorders, has the potential to improve clinical assessment, and in some cases leads to a diagnosis of the abnormality and thus provides a better understanding of lymphatic flow anomalies in patients with CLAs.

Experimental methods in chemical engineering: Pressure

AbstractPressure and temperature are the most important state variables for monitoring physicochemical processes to detect deviations that might lead to explosions and to verify levels, flow rate, and solids/gas hold‐up. Pressure fluctuations in multi‐phase systems identify regime changes and flow anomalies. Pressure signals are the first indicator of a process upset and are tied into distributed control systems (DCS) to sound alarms when they drift to high or low and activate safety interlocks in the case of high, high‐high, low, and low‐low conditions. To maximize the information, it requires that pressure gauges (transducers) are installed and calibrated precisely. Pressure measuring devices include manometers, aneroid devices like bellows and Bourdon gauges, and electronic instruments—piezoresistive, piezoelectric, and capacitive. The electronic elements have the advantage of higher precision and faster response times to measure fluctuations. The Bourdon gauges are standard equipment for pressure regulators and are mounted on the exterior of vessels and pipes to facilitate visual inspections. Over 2 million articles indexed by the Web of Science Core collection mention pressure, and in 2021, chemical engineering ranks had over 7000 articles—only multidisciplinary material sciences and energy and fuels had more. A bibliometric analysis identified five research clusters: temperature, combustion, and kinetics; separation, membranes, and energy efficiency; carbon dioxide (capture and storage), water, and thermodynamics; methane, adsorption, and transport phenomena (e.g., diffusion and permeability); and modelling, optimization, and computational fluid dynamics (CFD).

Anomaly inflow for subsystem symmetries

We study 't Hooft anomalies and the related anomaly inflow for subsystem global symmetries. These symmetries and anomalies arise in a number of exotic systems, including models with fracton order such as the $X$-cube model. As is the case for ordinary global symmetries, anomalies for subsystem symmetries can be canceled by anomaly inflow from a bulk theory in one higher dimension; the corresponding bulk is therefore a nontrivial subsystem symmetry protected topological (SSPT) phase. We demonstrate these phenomena in several examples with continuous and discrete subsystem global symmetries, as well as time-reversal symmetry. For each example we describe the boundary anomaly, and present classical continuum actions for the corresponding bulk SSPT phases, which describe the response of background gauge fields associated with the subsystem symmetries. Interestingly, we show that the anomaly does not uniquely specify the bulk SSPT phase. In general, the latter may also depend on how the symmetry and the associated foliation structure on the boundary are extended into the bulk.

Heat flow and gravity anomalies in some presumed hidden geothermal prospects in Java

The currently developed geothermal fields in Java are hosted by Quaternary volcanic complexes in the central zone of the island. Those fields have many vigorous thermal manifestations. However, seismic tomography shows the presence of an east-west-trending, low P-wave velocity (Vp) zones along the island. This indicates the presence of some hot, molten mass at depth, and provides the possibility of the existence of subsurface heat energy resource that can be utilized despite the rarity of surface manifestations. We investigate the heat flow and gravity anomalies in the areas lacking thermal manifestations, namely Paguyangan, Candi Umbul-Telomoyo, Pablengan, and Parang Wedang. The first three are associated with Slamet, Telomoyo, and Lawu volcanoes, respectively. Parang Wedang is far from the active Merapi volcano, but close to the Opak Fault – one of the major strike-slip faults of Java. This research is a preliminary effort in exploring those presumed hidden geothermal prospects. The results shows that all the investigated areas have high heat flow anomaly (145 – 160 mW/m2). Their gravity anomaly varies. The highest (>70 mGal) and medium values (12 - 24 mGal) are found in Pablengan, and Candi Umbul-Telomoyo, respectively. The lowest values (< 5 mGal) occur in Parang Wedang.

Statistical Study of Favorable Foreshock Ion Properties for the Formation of Hot Flow Anomalies and Foreshock Bubbles

AbstractHot flow anomalies (HFAs) and foreshock bubbles (FBs) are frequently observed in Earth's foreshock, which can significantly disturb the bow shock and therefore the magnetosphere‐ionosphere system and can accelerate particles. Previous statistical studies have identified the solar wind conditions (high solar wind speed and high Mach number, etc.) that favor their generation. However, backstreaming foreshock ions are expected to most directly control how HFAs and FBs form, whereas the solar wind may partake in the formation process indirectly by determining foreshock ion properties. Using Magnetospheric Multiscale mission and Time History of Events and Macroscale Interactions during Substorms mission, we perform a statistical study of foreshock ion properties around 275 HFAs and FBs. We show that foreshock ions with a high foreshock‐to‐solar wind density ratio (&gt;∼3%), high kinetic energy (&gt;∼600 eV), large ratio of kinetic energy to thermal energy (&gt;∼0.1), and large ratio of perpendicular temperature to parallel temperature (&gt;∼1.4) favor HFA and FB formation. We also examine how these properties are related to solar wind conditions: high solar wind speed and oblique bow shock (angle between the interplanetary magnetic field and the bow shock normal ) favor high kinetic energy of foreshock ions; foreshock ions have large ratio of kinetic energy to thermal energy at large (&gt;30°); small (&lt;30°), high Mach number, and closeness to the bow shock favor a high foreshock‐to‐solar wind density ratio. Our results provide further understanding of HFA and FB formation.

Induced topological gravity and anomaly inflow from Kähler-Dirac fermions in odd dimensions

We show that the effective action that results from integrating out massive K\"ahler-Dirac fermions propagating on a curved three-dimensional space is a topological gravity theory of Chern-Simons type. In the presence of a domain wall, massless, two-dimensional K\"ahler-Dirac fermions appear that are localized to the wall. Potential gravitational anomalies arising for these domain wall fermions are canceled via anomaly inflow from the bulk gravitational theory. We also study the invariance of the theory under large gauge transformations. The analysis and conclusions generalize straightforwardly to higher dimensions.

Hydrological and Meteorological Variability in the Volga River Basin under Global Warming by 1.5 and 2 Degrees

The idea of the research to assess the impact of 1.5 °C and 2 °C global warming in the 21st century on the runoff formation in the Volga basin corresponds to the Paris agreement on climate change 2016 with the main goal to keep the global air temperature rise to below 2 °C relative to the pre-industrial level and to take measures to limit warming to 1.5 °C by the end of the 21st century. The purpose of this study was to obtain physically based results of changes in the water regime of the Volga basin rivers under global warming by 1.5 °C and 2 °C relative to pre-industrial values. The physical and mathematical model of runoff generation ECOMAG (ECOlogical Model for Applied Geophysics) was applied in calculations using data from global climate models (GCMs). The estimation of flow anomalies of the Volga River and its major tributaries showed a decrease in annual runoff by 10–11% relative to the period from 1970 to 1999. The largest relative decrease in runoff by 17–20% was noted for the Oka and Upper Volga rivers, while the Kama River had only a 1–5% decrease. The Volga winter runoff increased by 17% and 28% under global warming by 1.5 °C and 2 °C, respectively, and negative runoff anomalies during the spring flood and the summer–autumn period turned out to be in the range of 21 to 23%. Despite the increase in precipitation, the role of evaporation in the water balance of the Volga basin will only increase.

Missing eddy feedback may explain weak signal-to-noise ratios in climate predictions

The signal-to-noise paradox that climate models are better at predicting the real world than their own ensemble forecast members highlights a serious and currently unresolved model error, adversely affecting climate predictions and introducing uncertainty into climate projections. By computing the magnitude of feedback between transient eddies and large-scale flow anomalies in multiple seasonal forecast systems, this study shows that current systems underestimate this positive eddy feedback, and that this deficiency is strongly linked to weak signal-to-noise ratios in ensemble mean predictions. Improved eddy feedback is further shown to be linked to greater teleconnection strength between the El Niño Southern Oscillation and the Arctic Oscillation and to stronger predictable signals. We also present a technique to estimate the potential gain in skill that may come from eliminating eddy feedback deficiency, showing that skill could double in some extratropical regions, significantly improving predictions of the Arctic Oscillation.

Network Flow Anomaly Detection Based on Improved Echo State Network

Aiming at the problems existing in the current network flow anomaly detection, a network flow prediction model based on echo state network of double loop reserve pool is designed, which solves the problem of reserve pool generated randomly in traditional echo state network and improves the accuracy and instantaneity of network flow prediction. Then, an anomaly detection method based on dynamic threshold is proposed, which takes the difference between the predicted value and the real value as the basis for judging the occurrence of anomalies. Simulation results show that the improved prediction model and anomaly detection method can effectively detect the abnormal behavior of network flow, and the detection effect is better than other models.

Effect of Advection by Upper-Tropospheric Background Zonal Wind on MJO Phase Speed

Abstract A robust linear regression algorithm is applied to estimate 95% confidence intervals on the background wind associated with Madden–Julian oscillation (MJO) upper-tropospheric atmospheric circulation signals characterized by different phase speeds. Data reconstructed from the ERA5 to represent advection by the upper-tropospheric background flow and MJO-associated zonal wind anomalies, together with satellite outgoing longwave radiation anomalies, all in the equatorial plane, are regressed against advection data filtered for zonal wavenumber 2 and phase speeds of 3, 4, 5, and 7 m s−1. The regressed advection by the background flow is then divided by the negative of the zonal gradient of regressed zonal wind across the central Indian Ocean base longitude at 80°E to estimate the associated background wind that leads to the given advection. The median estimates of background wind associated with these phase speeds are 13.4, 11.2, 10.5, and 10.3 m s−1 easterly. The differences between estimated values at neighboring speeds suggests that advection acts most strongly in slow MJO events, indicating that the slowest events happen to be slow because they experience stronger easterly advection by the upper-tropospheric background wind. Significance Statement The Madden–Julian oscillation (MJO) is the dominant subseasonal rainfall signal of the tropical atmosphere. This project shows that the background wind of the tropical atmosphere most especially slows down the slowest MJO events. Understanding what controls its speed might help scientists better predict events.

Detection of intrusions into the internet of things network by analyzing the presence of anomalies in the network traffic flow of aaa protocols

Detection of intrusions into the internet of things network by analyzing the presence of anomalies in the network traffic flow of aaa protocols

What Governs the Interannual Variability of Recurving North Atlantic Tropical Cyclones?

Abstract Recurving tropical cyclones (TCs) can cause extensive damage along the U.S. East Coast and later in their life cycle over Europe as post-tropical cyclones. While the existing literature attempts to understand the drivers of basinwide and regional TC variability, less work has been undertaken looking at recurving TCs. The roles played by the interannual variabilities of TC frequency and the steering flow in governing recurving TC interannual variability are investigated in this study. Using a track-matching algorithm, we identify observed TC tracks from the NHC “best track” hurricane database, version 2 (HURDAT2) in the ERA5 and MERRA2 reanalyses. This allows for detailed analysis of the post-tropical stages of the tracks in the observational TC record, enabling robust identification and separation of TCs that recurve. We show that over 75% of the interannual variance in annual recurving TC frequency can be explained by just two predictors—the frequency of TCs forming in the subtropical Atlantic, and hurricanes (TCs with wind speeds &gt; 33 m s−1) forming in the main development region (MDR). An index describing the seasonal mean meridional steering flow shows a weak, nonsignificant relationship with recurving TC frequency, supported by composite analysis. These results show that the interannual variability in recurving TC frequency is primarily driven by the seasonal TC activity of the MDR and the subtropical Atlantic, with seasonal anomalies in the steering flow playing a much smaller, secondary role. These results help to quantify the extent to which skillful seasonal forecasts of Atlantic hurricane activity benefit regions vulnerable to recurving TCs. Significance Statement Recurving tropical cyclones (TCs) can cause extensive damage to the U.S. East Coast, eastern Canada, and Europe. It is, therefore, crucial to understand why some years have a higher frequency of recurving TCs than other years. In this study, we show that the frequency of recurving TCs is very strongly linked to the frequency that hurricanes (TCs with wind speeds &gt; 33 m s−1) form in the main development region, and the frequency that TCs form in the subtropical Atlantic. This result suggests that skillful seasonal prediction of hurricane activity could be used to give enhanced seasonal warning to the regions often impacted by recurving TCs.

About geological theory

The author’s advection-polymorphic hypothesis of deep processes in the tectonosphere is based on V.V. Belousov’s system of endogenous regimes, a certain source of energy (radioactive decay in crustal and upper mantle rocks), and the method of energy transfer (advection). Elementary volumes of transported material have been termed «quanta of tectonic action» (QTA) with the diameter of about 50―70 km. The physical reality of such objects is proved. The choice of endogenous regime is related to the type of the preceding thermal model.&#x0D; The mechanism of the tectonosphere’s «heat machine», which relies firmly established facts and quantitatively explains the main events of geological history within the energy conservation law, has been substantiated.&#x0D; For any period, from the Early Archaean to our time, it is possible to numerically justify the pattern of heat and mass transfer, to select the endogenous regimes, and construct a non-stationary heat model and variation in time of the distribution of physical properties of rocks. By using the findings and solving only direct problems, one can determine the geological manifestations of the process and the anomalies of the physical fields. The results are compared with the observed ones (without fitting), and the discrepancies do not exceed the values due to the observation and calculation errors.&#x0D; Pursuant to the advection-polymorphic hypothesis, it became possible for the first time to predict: 1. The emergence of quanta of tectonic action. 2. Stability of parameters (depth and temperature) of magma chambers in the mantle in the history of the Earth. 3. Existence of the global asthenosphere (depth about 700―1000 km). 4. Velocity distribution of longitudinal seismic waves in the upper mantle of regions with all types of endogenous regimes. 5. The difference in the nature of earthquakes at various depths in the focal zones. Successful verification of predictions transfers the hypothesis into the rank of theory.&#x0D; The theory is used to explain the following at the quantitative level: dating of active processes on all platforms of the Earth, temperature distribution in the crust and upper mantle of platforms and active regions, sediment thickness in geosynclines and post-rift depressions, changes in mass flow in geological history, heat flow and gravitational field anomalies.&#x0D; Several applications of the theory to studies of seismicity and UHP-blocks problems and prospecting for mineral deposits (hydrocarbons, hydrothermal sulfide ores, diamonds, and geothermal energy resources) have been considered.

Hybrid Simulations of a Tangential Discontinuity‐Driven Foreshock Bubble Formation in Comparison With a Hot Flow Anomaly Formation

AbstractHot flow anomalies (HFAs) and foreshock bubbles (FBs) are significant foreshock transients that can accelerate particles and disturb the magnetosphere‐ionosphere system. Yet, their early formation mechanisms are still not fully understood. To investigate the formation of tangential discontinuity (TD)‐driven FBs and HFAs, we use 2‐D local hybrid simulations where a reflected or an injected warm foreshock ion beam can interact with a TD whose half‐thickness is comparable to the ion inertial scale. We show that the foreshock ions perform a partial gyration within, or across, the TD. Bulk motion differences between partially‐gyrating foreshock ions and fluid‐electrons lead to the generation of currents. As the trigger, these foreshock‐driven currents change the magnetic field topology around the TD and force the frozen‐in solar wind plasma to redistribute along with the field lines, shaping the foreshock transient. This confirms a recently proposed kinetic formation model. The extent of the magnetic field direction change across the TD within the foreshock ion gyromotion determines the current profile and thus the type of foreshock transient that forms. For a thin TD, the foreshock ions generate a current that is much stronger on the upstream side than the downstream side, forming an FB with one upstream compressional boundary. For the same foreshock ion gyroradius and magnetic shear, a thick TD yields comparable foreshock‐driven currents on the upstream and downstream sides, forming an HFA with two compressional boundaries. Our study suggests that the TD thickness is one of the factors that determine the formation of FBs and HFAs.

Chiral anomaly in Euler fluid and Beltrami flow

We show that barotropic flows of a perfect, charged, classical fluid exhibit an anomaly analogous to the chiral anomaly known in quantum field theories with Dirac fermions. A prominent effect of the chiral anomaly is the transport electric current in the fluid at equilibrium with the chiral reservoir. We find that it is also a property of celebrated Beltrami flows — stationary solutions of the Euler equation with an extensive helicity.

Heat transfer effect of SiC-GN hybrid nanocomposite with viscoplastic fluid in aircraft jet engine hoses

The flow characteristics of the heat-conducting viscoplastic fluid, namely Bingham added with high potential nanoparticles, such as Graphene nanoparticles(GN) and Silicon Carbide (SiC), have been investigated in the entry section of the intensified sustainable energy system. Hybrid nanocomposite GN-SiC has been prepared sampled with 25 wt% and synthesized using the reaction of hydrothermal, and its heat transfer effects have been studied using mathematical analysis. The prepared nanocomposite morphology has been examined by Scanning Electron Microscope (SEM). It has been observed that the GN-SiC is present in the composites, which indicates the presence of the above-mentioned hybrid nanocomposite that remains unchanging over the surface. Further, X-Ray Diffraction (XRD) has been used to characterize the prepared samples. Ethylene glycol has been used as a base fluid to prepare the nanofluids. The motionless concentric smooth surface hoses are considered as an intensified system in an aircraft jet engine. The efficiency of heat transfer with the influence of different velocities and pressure has been analyzed and reported. This analysis may lead to a better understanding of the flow characteristics and anomalies of coolant, which may be of interest in the engine systems and may help in the industrial equipment and possibly in their process.

Generalized relation of bitumen stress at shear to its penetration in a range from softening point temperature to breaking point temperature

The problem of assessing the quality of bitumen is in the fact that the common quality indicators are empirical. They do not allow the objective characterization neither the consistency of bitumen no its transition from one state of matter to other. Goal. The solution to this problem is based on the principle that the resistance of bitumen to the penetration of the needle is a shear characteristic under conditions of complete adhesion to the surface of the needle. Methodology. The practical confirmation of this approach is based on the Core &amp; Laurent method, which takes into account the rate of the bitumen layer and the resistance force to this displacement based on the geometric parameters of the needle and the force applied to it. Attempts to estimate bitumen viscosity with the depth of needle penetration have failed for two reasons. Firstly, bitumen viscosity is principally a technological characteristic. Secondly, in the simple conversion of the penetration value into viscosity neither the shear rate nor flow anomalies and a units ratio were taken into account. Results. In this research work the shear stress at penetration at the softening point temperature and breaking point temperature is taken as a mechanical characteristic of the states of matter. This statement of the problem is based on the linearity of the relationship between the test temperature and log of penetration, established by Hekelom. Later, this relationship was supplemented with a temperature of equal penetration T31 as a midpoint of the plasticity interval of bitumen with the same penetration but different penetration indexes. Practical value of this work is results in finding the relation between penetration and the reverse pliability G*/sin φ, which is applied in the Superpave system to evaluate the bitumen component in the rutting resistance of asphalt concrete.

Exploring the association between anomalies and multifractality variations in river flow time series

ABSTRACT Monitoring and predicting river floods have always been of concern for hydrologists. Anomalies in flow patterns alert us of upcoming events. The effect of such anomalies on the multifractality and nonlinear dynamics of the river flow is investigated in this research. The river flow of the River Trent in England from 2018 to 2019 was dissected using the multifractal, power spectrum, and phase space reconstruction techniques. Results show a reduction in multifractality strength before the anomalies in the time series. Moreover, receding trajectories from the attractor in the phase space and augmentation of the power spectrum confirmed a decline in flow multifractality due to anomalies. A compliance comparison of multifractality reduction before anomalies in river flow leads to predicting river floods approximately 12 days in advance. Furthermore, if the multifractal strength does not return to its equilibrium, this is a warning that floods are expected in the near future (less than 10 days).

Influence of wall slip, thixotropy and lubrication regime on the instrumental sensory evaluation of topical formulations.

Drawing parallels from rheotribology can be used to develop a robust instrumental protocol for non-subjective characterization, product development and design of topical dosage forms with desired sensory attributes. However, instrumental characterization of cosmetic products can be influenced by the measurement protocol, thixotropy, flow anomalies like shear banding or wall slip and nature of the film formed on the skin surface. In this study, we evaluated the influence of above parameters on the instrumental sensory evaluation of 12 topical formulations of different galenic forms. Oscillatory strain sweep measurements (SAOS and LAOS) were performed to investigate the influence of frequency and wall slip on the material parameters. The textural attributes at different consumer touchpoints were evaluated by accounting time-dependent simulation of viscoelastic flow. Further, the influence of film thickness and sample drying on the tactile properties of the topical formulations were studied on a non-biological skin model using a sliding probe tribometer. The study shows that the flow properties of the semi-solid formulations depend on the timescale of the problem. A few formulations exhibited wall slip to varying degrees in the linear viscoelastic regime where the behaviour was found not to be characteristic of a particular topical dosage form. The material functions obtained from the Lissajous plots suggest that the non-linear flow behaviour of different galenic forms is least influenced by the boundary conditions imposed by the measurement geometry. The results were statistically analysed using principal component analysis where the attributes used for discriminating skin creams during pick up and rub out are found to be closely associated with non-linear rheology. The friction coefficient exhibited speed dependence where it formed different parametric group with rheological data depending on the lubrication regime. The study highlights that correlations are possible amongst rheological, tribological and instrumental textural analysis data, which can act an impetus for the development of models to predict attributes that drive perception at different consumer touchpoints. However, the choice of instrumental settings, anomalies associated with rheological measurements and friction dependence on a number of parameters can influence the model prediction.

Regional thermal anomalies derived from magnetic spectral analysis and 3D gravity inversion: Implications for potential geothermal sites in Tanzania

Tanzania is one of the several countries intersected by the East African Rift System (EARS) endowed by a geothermal potential that has been explored only to a limited extent. Here we present the first heat flux map over the region based on the Curie point depth (CPD) estimation from aeromagnetic data. We have estimated the base of magnetic sources as a proxy for the CPD from the radially average power spectra of the total magnetic field using the centroid and the de-fractal methods. Our results show that the CPDs range ca. 11 to 43 km and are comparable to, but more detailed than global CPD estimates. The heat flow has then been computed assuming a constant thermal conductivity. In order to evaluate the results against crustal thickness, we have inverted the gravimetric regional field data constrained by the existing Moho depth from seismic receiver functions. Our analysis has revealed high heat flow values (over 100 mW/m2) along the EARS and at the Proterozoic collision boundaries that have been reactivated by the EARS. In general, the high heat flow anomalies coincide with known surface geothermal manifestations and shallow Moho depth in the range ca. 30 to 35 km. A high heat flow anomaly is also found in the central part of the Tanzanian craton, likely related to the mantle plume imaged by seismic tomography. The most interesting areas for geothermal exploration in Tanzania, according to our results, are the EARS triple junction in the Rungwe volcanic province, the north Tanzania divergent zone and the areas of the Proterozoic collision boundaries reactivated by the EARS.