Gradient Of Solution Research Articles

On Instability of a Dusty Stellar Atmosphere in Stern’s Type Configuration

The thermal-convective instability of a stellar atmosphere in the presence of a stable solute gradient in Stern’s type configuration is studied in the presence of suspended particles. The criteria for monotonic instability are derived which are found to hold well in the presence of uniform rotation and uniform magnetic field, separately, on the thermosolutal-convective instability of a stellar atmosphere in the presence of suspended particles.

MP43-02 COMBINATION OF MICROSCOPIC TESTICULAR SPERM EXTRACTION (MTESE) AND DENSITY GRADIENT PROCESSING TO OPTIMIZE SPERM RETRIEVAL AND PREGNANCY OUTCOMES IN MEN WITH NONOBSTRUCTIVE AZOOSPERMIA (NOA)

You have accessJournal of UrologyCME1 Apr 2023MP43-02 COMBINATION OF MICROSCOPIC TESTICULAR SPERM EXTRACTION (MTESE) AND DENSITY GRADIENT PROCESSING TO OPTIMIZE SPERM RETRIEVAL AND PREGNANCY OUTCOMES IN MEN WITH NONOBSTRUCTIVE AZOOSPERMIA (NOA) Nicholas Deebel, Banafsheh Nikmehr, Janmejay Hingu, Collette O'Connor, Rachel Ruble, Yueqiang Song, Ayse Vuruskan, Anuradha Devineni, Cihan Halicigil, Stuart Howards, Tamer Yalcinkaya, and Hooman Sadri-Ardekani Nicholas DeebelNicholas Deebel More articles by this author , Banafsheh NikmehrBanafsheh Nikmehr More articles by this author , Janmejay HinguJanmejay Hingu More articles by this author , Collette O'ConnorCollette O'Connor More articles by this author , Rachel RubleRachel Ruble More articles by this author , Yueqiang SongYueqiang Song More articles by this author , Ayse VuruskanAyse Vuruskan More articles by this author , Anuradha DevineniAnuradha Devineni More articles by this author , Cihan HalicigilCihan Halicigil More articles by this author , Stuart HowardsStuart Howards More articles by this author , Tamer YalcinkayaTamer Yalcinkaya More articles by this author , and Hooman Sadri-ArdekaniHooman Sadri-Ardekani More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003289.02AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: mTESE with Intracytoplasmic sperm injection (ICSI) is the gold standard for treating infertile couples when NOA in the male is present. However, using conventional tissue processing techniques, many patients will remain negative for sperm on mTESE. Standard practice in assisted reproduction technology (ART) does not utilize the density gradient centrifugation process following mTESE. We hypothesize that gradient utilization can enrich sperm retrieval following mTESE. METHODS: Men with NOA underwent mTESE from 2019-2022 by a single surgeon. The biopsy specimens underwent mechanical dissection. Subsequent tissue processing and gradient wash were carried out through a gradient column including 90% and 50% gradient solution diluted in standard sperm wash medium. Upon verification of sperm, the post-gradient sperm and remaining un-dissociated tissue were cryopreserved separately. On the day of ICSI, the frozen gradient sperm were thawed to recover viable sperm. If needed, frozen tissue was thawed, subjected to mechanical dissociation, and a subsequent gradient to obtain enough viable sperm. Fertilization and embryo development were assessed morphologically with the Embryoscope and genetically with preimplantation genetic testing for aneuploidy (PGT-A). Following embryo transfer, biochemical (ß-HCG) and clinical (gestational sac) pregnancy were assessed. RESULTS: Overall, 24 male patients (36±1.5 years old) with NOA underwent mTESE for an average operating time of 110.6±6.9 minutes (range: 37-177). The primary sperm identification rate after mechanical dissociation of tissue was 37.5% (n=9). The use of the density gradient led to an overall sperm retrieval rate of 70.8% (n=17) (p<0.05) and secondary sperm retrieval rate (sperm identification in initially negative patients) of 53.3% (n=8). Retrieved sperm were cryopreserved to be used for ICSI. Thirteen couples (average female age and AMH 32.1±1.6 and 3.2±0.8 ng/ml respectively) underwent ICSI using extracted sperm. The overall fertilization, per-cycle pregnancy, and per-transfer pregnancy rates were 66%, 76%, and 100% respectively. Amongst these couples, 6 underwent PGT-A, and 70.0% of tested blastocysts were euploid. CONCLUSIONS: Utilization of mTESE with subsequent gradient technology may serve as a highly sensitive sperm detection and enrichment method for NOA patients in order to obtain superior ART outcomes. Source of Funding: NA © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e601 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Nicholas Deebel More articles by this author Banafsheh Nikmehr More articles by this author Janmejay Hingu More articles by this author Collette O'Connor More articles by this author Rachel Ruble More articles by this author Yueqiang Song More articles by this author Ayse Vuruskan More articles by this author Anuradha Devineni More articles by this author Cihan Halicigil More articles by this author Stuart Howards More articles by this author Tamer Yalcinkaya More articles by this author Hooman Sadri-Ardekani More articles by this author Expand All Advertisement PDF downloadLoading ...

Effect of polymer/surfactant complexation on diffusiophoresis of colloids in surfactant concentration gradients

HypothesisA concentration gradient of surfactants in the presence of polymers that non-covalently associate with surfactants will exhibit a continually varying distribution of complexes with different composition, charge, and size. Since diffusiophoresis of colloids suspended in a solute concentration gradient depends on the relaxation of the gradient and on the interactions between solutes and particles, polymer/surfactant complexation will alter the rate of diffusiophoresis driven by surfactant gradients relative to that observed in the same concentration gradient in the absence of polymers. ExperimentsA microfluidic device was used to measure diffusiophoresis of colloids suspended in solutions containing a gradient of sodium dodecylsulfate (SDS) in the presence or absence of a uniform concentration of Pluronic P123 poly(ethylene oxide-b-propylene oxide-b-ethylene oxide) nonionic triblock copolymers. To interpret the effect of P123 on the rate of colloid diffusiophoresis, electrophoretic mobility and dynamic light scattering measurements of the colloid/solute systems were performed, and a numerical model was constructed to account for the effects of complexation on diffusiophoresis. FindingsPolymer/surfactant complexation in solute gradients significantly enhanced diffusiophoretic transport of colloids. Large P123/SDS complexes formed at low SDS concentrations yielded low collective solute diffusion coefficients that prolonged the existence of strong concentration gradients relative to those without P123 to drive diffusiophoresis.

Weak differentiability to nonuniform nonlinear degenerate elliptic systems under p,q-growth condition on the Heisenberg group

The paper concerns the weak differentiability of weak solutions to two kinds of nonuniform nonlinear degenerate elliptic systems under the p,q-growth condition on the Heisenberg Group. We use the iteration to fractional difference quotients on the Heisenberg Group to get the weak differentiability of weak solution u in the vertical direction (i.e., Lp(1<p<4) integrability of Tu) and then the second order weak differentiability of weak solution in the horizontal directions (i.e., L2 integrability of ∇H2u) and weak differentiability of gradient of weak solution in the vertical direction (i.e., L2 integrability of T∇Hu)).

Adjoint-based robust optimization design of laminar flow wing under flight condition uncertainties

It is an inherent uncertainty problem that the application of laminar flow technology to the wing of large passenger aircraft is affected by flight conditions. In order to seek a more robust natural laminar flow control effect, it is necessary to develop an effective optimization design method. Meanwhile, attention must be given to the impact of crossflow (CF) instability brought on by the sweep angle. This paper constructs a robust optimization design framework based on discrete adjoint methods and non-intrusive polynomial chaos. Transition prediction is implemented by coupled Reynolds-Averaged Navier-Stokes (RANS) and simplified eN method, which can consider both Tollmien-Schlichting (TS) wave and crossflow vortex instability. We have performed gradient enhancement processing on the general Polynomial Chaos Expansion (PCE), which is advantageous to reduce the computational cost of single uncertainty propagation. This processing takes advantage of the gradient information obtained by solving the coupled adjoint equations considering transition. The statistical moment gradient solution used for the robust optimization design also uses the derivatives of coupled adjoint equations. The framework is applied to the robust design of a 25° swept wing with infinite span in transonic flow. The uncertainty quantification and sensitivity analysis on the baseline wing shows that the uncertainty quantification method in this paper has high accuracy, and qualitatively reveals the factors that dominate in different flow field regions. By the robust optimization design, the mean and standard deviation of the drag coefficient can be reduced by 29% and 45%, respectively, and compared with the deterministic optimization design results, there is less possibility of forming shock waves under flight condition uncertainties. Robust optimization results illustrate the trade-off between the transition delay and the wave drag reduction.

A numerical investigation to determine longitudinal dispersion coefficient in ideal and randomized reticulated porous structures using transient direct pore level simulation

The purpose of this numerical investigation is to characterize the longitudinal dispersion coefficients in open-cell reticulated porous structures. Open-cell foams are modelled using idealized Kelvin cell structures. Using the conventional Navier–Stokes equation, airflow has been calculated through various porous structures. Along with the flow, the dispersion of a tracer fluid is traced across the structures and analyzed in terms of the effective dispersion coefficient. Using direct pore level simulations (DPLS), a parametric study is performed to understand the influence of geometrical parameters on the dispersion in porous media. To evaluate the longitudinal dispersion coefficient (LDC), the analytic solution gradients were fitted into the simulated gradients. From the results, a new characteristic length correlation is proposed to calculate the Peclet number, and it is compared with experimental and numerical data that are available in the literature.

Soil microbial communities regulate the threshold effect of salinity stress on SOM decomposition in coastal salt marshes

Salinity stress is one of the critical environmental drivers of soil organic matter (SOM) decomposition in coastal ecosystems. Although the temperature sensitivity (Q10) of SOM decomposition has been widely applied in Earth system models to forecast carbon processes, the impact of salinity on SOM decomposition by restructuring microbial communities remains uncovered. Here, we conducted a microcosm experiment with soils collected from the coastal salt marsh in the Yellow River Estuary, which is subjected to strong dynamics of salinity due to both tidal flooding and drainage. By setting a gradient of salt solutions, soil salinity was adjusted to simulate salinity stress and soil carbon emission (CO2) rate was measured over the period. Results showed that as salinity increased, the estimated decomposition constants based on first-order kinetics gradually decreased at different temperatures. Below the 20‰ salinity treatments, which doubled the soil salinity, Q10 increased with increasing salinity; but higher salinity constrained the temperature-related response of SOM decomposition by inhibiting microbial growth and carbon metabolisms. Soil bacteria were more sensitive to salinity stress than fungi, which can be inferred from the response of microbial beta-diversity to changing salinity. Among them, the phylotypes assigned to Gammaproteobacteria and Bacilli showed higher salt tolerance, whereas taxa affiliated with Alphaproteobacteria and Bacteroidota were more easily inhibited by the salinity stress. Several fungal taxa belonging to Ascomycota had higher adaptability to the stress. As the substrate was consumed with the incubation, bacterial competition intensified, but the fungal co-occurrence pattern changed weakly during decomposition. Collectively, these findings revealed the threshold effect of salinity on SOM decomposition in coastal salt marshes and emphasized that salt stress plays a key role in carbon sequestration by regulating microbial keystone taxa, metabolisms, and interactions.

Optimal Regularity for Elliptic Equations With Measurable Nonlinearities Under Nonstandard Growth

Abstract We are concerned with weak solutions of elliptic equations involving measurable nonlinearities with Orlicz growth to address what would be the weakest regularity condition on the associated nonlinearity for the Calderón–Zygmund theory. We prove that the gradient of weak solution is as integrable as the nonhomogeneous term under the assumption that the nonlinearity is only measurable in one of the variables while it has a small BMO assumption in the other variables. To this end, we develop a nonlinear Moser-type iteration argument for such a homogeneous reference problem with one variable–dependent nonlinearity under Orlicz growth to establish $W^{1,q}$–regularity for every $q&amp;gt;1$. Our results open a new path into the comprehensive understanding of the problem with nonstandard growth in the literature of optimal regularity theory in highly nonlinear elliptic and parabolic equations.

Hybrid asynchronous isogeometric Perfectly Matched Layer for transient elastodynamics

This paper presents an isogeometric formulation (IGA) of the Perfectly Matched Layer (PML) for two-dimensional time-domain elastodynamics in unbounded media. The displacement-based unsplit-field PML formulation is first discretized in space using B-spline basis functions of increasing polynomial order p, from 2 to 10, able to deal with the strong solution gradients in the thickness of the PML thanks to the high order continuity provided by the B-spline basis functions. In order to keep the high accuracy of IGA, implicit time integration is chosen in the PML subdomains, whereas the physical domain is integrated with an explicit time integration scheme. The domain decomposition is based on a dual formulation and Heterogeneous Asynchronous Time Integrator (HATI) approach. The coupling between non-conforming IGA-patches for the PML subdomains and the physical domain is carried out using a standard mortar method. It enables us to select for the IGA-PML subdomains both the appropriate space discretization and the appropriate time discretization with an implicit time integrator and a larger time step size. The hybrid multi-time step IGA-PML performance in terms of computation time, is assessed for two-dimensional elastodynamic problems in single and multi-layer media depending on the chosen discretization parameters in space and time.

Flow behavior of nano-silica solutions in cement cracks/fractures

One of the most prevalent causes of failure in oil and gas wells is the formation of cracks in the wellbore cement. The cracks can lead to loss of zonal isolation and fluid leakage to the surface. Compared to cement slurry which is difficult to squeeze into the cracks due to its high-solid content, nanoparticle (NP) gels have gained significant attraction for sealing fractures/cracks in oil and gas wells. It is highly desirable to know the flow behavior of NP solutions in the cracks. This study investigated the flow of nano-silica solutions through narrow rectangular cross-sections simulating sealant flow in cracks of oil well cement sheath. Pressure gradient was tested at 4 flow rates for various aspect ratios of the rectangular cross-sections. For a given cross-section of conduit, pressure drop increased with flow rate. For a given conduit height, the pressure drop decreased with conduit width due to increased flow area. Pressure drop increased as the conduit height reduced. These characteristics of nan-particle solution flow are like those found for conventional fluids. The pressure gradient of nano-silica solution flow in a conduit of a given rectangular cross-section is nearly proportional to flow velocity at tested flow rates, indicating laminar flow conditions in the tested flow conditions. The proportionality factor (rate of increase) increases as the aspect ratio of the cross-section decreases (slot becomes narrower). This is because a system with a lower aspect ratio has four boundaries that generate a 2-dimensional velocity profile, while a system with a higher aspect ratio has essentially two boundaries that generate a 1-dimensional velocity profile. More boundaries mean more frictional resistance to fluid flow. Hydraulics models for conventional fluid flow through conduits of rectangular cross-sections under-predict the pressure gradient of nano-silica solution. The discrepancy/difference is over 90% in pressure gradient prediction in general. The hydraulics model presented by Guo et al. (2022) with aspect ratio is better than the classical hydraulics model with hydraulic diameter. However, both models fail to predict the pressure gradient along the conduits with slot-like cross sections. The excessive pressure drop is attributed to the interactions between the nano-particles and conduit walls. Further investigations are required to gain a thorough understanding of nano-silica flow.

Asymptotic behavior of solutions to the Monge-Ampère equations with slow convergence rate at infinity

Abstract We consider the asymptotic behavior of solutions to the Monge-Ampère equations with slow convergence rate at infinity and fulfill previous results under faster convergence rate by Bao et al. [Monge-Ampère equation on exterior domains, Calc. Var PDE. 52 (2015), 39–63]. Different from known results, we obtain the limit of Hessian and/or gradient of solution at infinity relying on the convergence rate. The basic idea is to use a revised level set method, the spherical harmonic expansion, and the iteration method.

Investigating mechanisms of laser pulse-induced reflectivity modulations in photoacoustic remote sensing with a 10 million frames-per-second camera

Photoacoustic remote sensing has been recently developed as an all-optical imaging modality capable of imaging a variety of endogenous contrast agents label-free. Initially predicted laser pulse-induced refractive index perturbation-based interrogation beam reflectivity modulations have been found to be orders of magnitude smaller than those typically observed experimentally. In this report we utilize a 10 million frames-per-second camera to further investigate these predicted reflectivity modulations, while also exploring other potential mechanisms of laser pulse-induced reflectivity modulations. Laser-induced motion is demonstrated both laterally for gold wires suspended and submerged in air and water, respectively, and carbon fibers submerged in water, and axial motion is observed in gold wires submerged in a depth gradient of intralipid solution. This laser-induced sample motion is anticipated to cause reflectivity modulations local to the interrogation beam profile in microscopy set-ups. Non-motion-based maximum intensity modulations of 3% are also observed in gold wires submerged in water, indicating the presence of the originally predicted reflectivity modulations. Overall, these observations are important as they provide a widefield view of laser-pulse interactions unavailable in previous point scanning-based photoacoustic remote sensing microscopy configurations, where observed mechanisms occur on time-scales orders of magnitude faster than equivalent field of view point scanning capabilities.

Diffusiophoresis of hydrophobic spherical particles in a solution of general electrolyte

The present article deals with the diffusiophoresis of hydrophobic rigid colloids bearing arbitrary ζ-potential. We derived the generic expression for the diffusiophoretic velocity of such a colloid exposed in an externally applied concentration gradient of the general electrolyte solution. The derived expression takes into account the relaxation effect and is applicable for all values of surface ζ-potential and hydrodynamic slip length at large κa (κa≥ca.50), where κ−1 is the thickness of the electric double layer and a is the particle radius. We further derived several closed-form expressions for particle velocity derived under various electrostatic and hydrodynamic conditions when the particle is exposed in an applied concentration gradient of binary symmetric (e.g., z:z), asymmetric (1:2, 2:1, 3:1, 1:3), and a mixed electrolyte (mixture of 1:1 and 2:1 electrolytes). The results for diffusiophoretic velocity are further illustrated graphically to indicate the mutual interaction of chemiphoresis, induced electrophoresis due to unequal mobilities of cations and anions of the electrolyte, and the mechanism by which the sufficiently charged particle migrates opposite to the direction of the applied concentration gradient. The impact of hydrophobicity is further discussed.

Local bounds of the gradient of weak solutions to the porous medium equation

Let $u$ be a nonnegative, local, weak solution to the porous medium equation for $m\ge2$ in a space-time cylinder $\Omega_T$. Fix a point $(x_o,t_o)\in\Omega_T$: if the average \[ a{\buildrel\mbox{def}\over{=}}\frac1{|B_r(x_o)|}\int_{B_r(x_o)}u(x,t_o)\,dx>0, \] then the quantity $|\nabla u^{m-1}|$ is locally bounded in a proper cylinder, whose center lies at time $t_o+a^{1-m}r^2$. This implies that in the same cylinder the solution $u$ is H\"older continuous with exponent $\alpha=\frac1{m-1}$, which is known to be optimal. Moreover, $u$ presents a sort of instantaneous regularisation, which we quantify.

A general sufficient criterion for energy conservation in the Navier–Stokes system

In this paper, we derive an energy conservation criterion based on a combination of velocity and its gradient for the weak solutions of both the homogeneous incompressible Navier–Stokes equations and the general compressible Navier–Stokes equations. For the incompressible case, this class implies almost known corresponding results on periodic domain via either the velocity or its gradient including the famous Lions' energy conservation criterion obtained in [1, Rend. Semin. Mat. Univ. Padova, 30 (1960)]. For the compressible case, this helps us to extend the previously known criteria for the energy conservation of weak solutions from the incompressible fluid to compressible flow and improve the recent results due to Nguyen‐Nguyen‐Tang in [26, Nonlinearity, 32 (2019)] and Liang in [27, Proc. Roy. Soc. Edinburgh Sect. A, (2020)].

Oscillatory instability caused by the interplay of Soret effect and cross-diffusion

We show that a subtle coupling between the thermal and solutal gradients driven by the thermodiffusion, cross-diffusion, and buoyancy force can lead to oscillatory dynamic behavior of a ternary mixture in the thermogravitational column. The potentially unstable stratification results from the interplay of mass fluxes of the two heaviest components where the leading role belongs to one of them. Our experiments and numerical analysis not only evidence the presence of oscillatory instability but also demonstrate the emergence of the secondary instability in the form of swinging pattern in addition to the large-scale standing wave. We suggest that the region, where oscillatory instability occurs, is characterized by opposite signs of Soret ST1′ and thermodiffusion DT1′ coefficients due to large cross-diffusion contribution.

Feature Selection for Airbone LiDAR Point Cloud Classification

The classification of airborne LiDAR data is a prerequisite for many spatial data elaborations and analysis. In the domain of power supply networks, it is of utmost importance to be able to discern at least five classes for further processing—ground, buildings, vegetation, poles, and catenaries. This process is mainly performed manually by domain experts with the use of advanced point cloud manipulation software. The goal of this paper is to find a set of features which would divide space well enough to achieve accurate automatic classification on all relevant classes within the domain, thus reducing manual labor. To tackle this problem, we propose a single multi-class approach to classify all four basic classes (excluding ground) in a power supply domain with single pass-through, using one network. The proposed solution implements random forests and gradient boosting to create a feature-based per-point classifier which achieved an accuracy and F1 score of over 99% on all tested cases, with the maximum of 99.7% for accuracy and 99.5% for F1 score. Moreover, we achieved a maximum of 81.7% F1 score for the most sparse class. The results show that the proposed set of features for the LiDAR data cloud is effective in power supply line classification.

A FFT accelerated fourth order finite difference method for solving three-dimensional elliptic interface problems

In this paper, a fourth order augmented matched interface and boundary (AMIB) method is proposed for solving a three-dimensional elliptic interface problem which involves a smooth material interface inside a cuboid domain. On the boundary of the cuboid domain, the fourth order AMIB method can handle different types of boundary conditions, including Dirichlet, Neumann, Robin and their mix combinations in fictitious value generation. Moreover, zero-padding solutions are introduced so that the fast Fourier transform (FFT) algorithm is still valid near the boundary. In dealing with the interior interface, a fourth order ray-casting matched interface and boundary (MIB) scheme is proposed, which enforces the jump conditions along the normal direction for calculating fictitious values. Comparing with the existing MIB scheme, the ray-casting scheme naturally bypasses the corner issue and becomes more robust in handling complex geometry. Based on fictitious values generated near interface and boundary, the fourth order central difference can be corrected at various irregular points including corner points, by introducing Cartesian derivative jumps as auxiliary variables. This gives rise to an enlarged linear system, which can be efficiently solved by the Schur complement procedure together with the FFT inversion of the discrete Laplacian. Extensive numerical experiments have been carried to test the proposed ray-casting AMIB method for numerical accuracy, efficiency, and robustness in corner treatment. The numerical results demonstrate that the ray-casting AMIB scheme not only maintains a fourth order of accuracy in treating various interfaces and boundaries for both solutions and solution gradients, but also attains an overall efficiency on the order of O(n3log⁡n) for a n×n×n uniform grid.

On the ore-formational affiliation of gold deposits of the Beltau-Kuramin volcano-plutonic belt in Eastern Uzbekistan (according to thermobarogeochemical data)

&#x0D; &#x0D; &#x0D; Gold deposits in the Beltau-Kuramin volcano-plutonic belt (Eastern Uzbekistan) are traditionally considered mineral products of the volcanogenic-hydrothermal class of shallow formations. However, geological, geochemical, isotope-geochemical and precise thermo- barogeochemical studies of the physical and chemical conditions of their formation give reason to question their shallow nature. Comparison of the thermobaric conditions of ore-genesis, the chemical composition of the fluid’s aqueous and gas phases, the value of the paleotemperature gradient (ΔT/100 m) of the hydrothermal solutions of the Kochbulak and Kyzil-Alma deposits with those belonging to the medium-depth formation of the plutonic-hydrothermal class (Lyahov, 1988; Lyahov, Pavlun, Piznyur, Popivnyak, 1995) shows that there are much more similarities than differences with genotypic deposits of medium depths. Signs that call into question the shallow nature of gold deposits in the Beltau-Kuramin volcanic-plutonic belt include the following: interspersion of gold ore process and dike magmatism; high-medium temperature level of hydrothermal processes (&gt; 390–200 °С); relatively high pressure in the mineral formation system (from 40 to &gt; 58 MPa); a high content of Na+ and Cl– ions in solutions of fluid inclusions according to the data of triple water extractions and a significant predominance of Na+ over K+ (by two to five times); high and predominant content in the gas phase of the productive stage solutions of CO2 (up to 97 %) and CH4 (up to 45%); the presence in fluid inclusions at room temperature of a liquid phase of CO2 of relatively high density (up to 0.560 g/cm3); high purity of native gold of early generations; exclusively electronic electrical conductivity of galena; relatively insignificant paleotemperature gradient (ΔТ/100 m) in ore bodies of different morphology (15–20 °С/100 m for vein structures and 9–12 °С/100 m for ore-explosive ones). Geological data indicate a large erosion section of ore-conjugated morphostructures, which is at least 2000–2500 m, depending on the depression or domed nature of the volcanic morphostructures. At shallow depths of the formation of the syn-ore paleosurface, the gold deposits would have been completely eroded, while in the modern erosion section there is a large scale of vertical mineralization. Ore-formation correlation of gold deposits in Eastern Uzbekistan increases the prospect of deep horizons of these deposits, as well as gold-bearing areas and ore occurrences, where prospecting and evaluation work will be carried out.&#x0D; &#x0D; &#x0D;

Convection Confounds Measurements of Osmophoresis for Lipid Vesicles in Solute Gradients.

Lipid vesicles immersed in solute gradients are predicted to migrate from regions of high to low solute concentration due to osmotic flows induced across their semipermeable membranes. This process─known as osmophoresis─is potentially relevant to biological processes such as vesicle trafficking and cell migration; however, there exist significant discrepancies (several orders of magnitude) between experimental observations and theoretical predictions for the vesicle speed. Here, we seek to reconcile predictions of osmophoresis with observations of vesicle motion in osmotic gradients. We prepare quasi-steady solute gradients in a microfluidic chamber using density-matched solutions of sucrose and glucose to eliminate buoyancy-driven flows. We quantify the motions of giant DLPC vesicles and Brownian tracer particles in such gradients using Bayesian analysis of particle tracking data. Despite efforts to mitigate convective flows, we observe directed motion of both lipid vesicles and tracer particles in a common direction at comparable speeds of order 10 nm/s. These observations are not inconsistent with models of osmophoresis, which predict slower motion at ca. 1 nm/s; however, experimental uncertainty and the confounding effects of fluid convection prohibit a quantitative comparison. In contrast to previous reports, we find no evidence for anomalously fast osmophoresis of lipid vesicles when fluid convection is mitigated and quantified. We discuss strategies for enhancing the speed of osmophoresis using high permeability membranes and geometric confinement.