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Effects of Surface Drag and Mid-level Shear Magnitude on Idealized High-Shear, Low-CAPE Quasi-Linear Convective System Cold Pools and Vortex Development
No full textHigh-shear low-CAPE (HSLC) tornadic convective events have been of particular interest in recent years, given their complex environments and propensity to occur at times and locations that increase threats to life and property. Past numerical and observational studies have identified the potential for baroclinically generated vorticity that develops in quasi-linear convective system (QLCS) downdrafts to play a role in the development of mesovortices and tornadoes, but it is not certain how prevalent these mechanisms are in HSLC QLCSs. To investigate the importance of baroclinic vorticity generation for vortexgenesis, this study presents six idealized QLCS simulations, four of which are HSLC. These simulations are initialized with varying mid-level shear and lower boundary conditions (free-slip and semislip) that affect cold-pool characteristics and thus baroclinic vorticity generation.
Increasing mid-level shear reduces the number of TLVs that develop over a 3-hour period, due to weaker updrafts and possible inhibition of horizontal shearing instability release. Semislip simulations also have fewer and less intense TLVs than the free-slip simulations due to weaker convergence at the surface which results in broader vortices. Vortices develop and are maintained due to various combinations of the following mechanisms: environmental vorticity being depressed by a downdraft ahead of the surface cold pool, horizontal shearing instability release, tilting of frictionally generated vorticity into the vertical, and baroclinic vorticity generation. Additionally, a novel mechanism is identified that involves baroclinic and frictional vortex lines being tilted in opposite directions at different heights via cold-pool lobes and clefts, resulting in positive and negative vertical vorticity stacked in the same locations, leading to deeper vortices. The array of vorticity sources identified here suggest that while baroclinic vorticity generation is playing both direct and indirect roles in vortexgenesis in these simulations, the relative importance of specific baroclinic mechanisms is difficult to deduce as several vorticity genesis mechanisms can be concurrently active in a single vortex
SWCPC 438 #63 Samuel Burks Burnett (duplicate), undated.
No full textThe collection features portraits of sixty-one prominent cattle ranchers, both male and female, who were considered to be the “Cattle Kings of Texas.
SWCPC 438 Negatives #68 Kerville, Texas (?), undated.
No full textThe collection features portraits of sixty-one prominent cattle ranchers, both male and female, who were considered to be the “Cattle Kings of Texas.
Tuning a magnetic energy scale with pressure and field in UTe2
No full textWhen a fragile ordered state is suppressed to zero temperature, a quantum phase transition occurs, which is often marked by the appearance of unconventional superconductivity. While the quantum critical point can be hidden, the influence of the quantum criticality extends to fairly high temperatures, manifesting non-Fermi liquid behavior in a wide range of the field-temperature-pressure phase space. Here, we report the tuning of a magnetic energy scale in the heavy-fermion superconductor UTe2, previously identified with a peak in the c-axis electrical transport temperature dependence, using applied hydrostatic pressures and a-axis-oriented magnetic fields as complementary (and opposing) tuning parameters: the characteristic peak in c-axis resistivity decreases in temperature with applied pressure before vanishing near the critical pressure of 15 kbar (1.5 GPa), while the application of field shifts the peak to a higher temperature and broadens it under all studied pressures. At the critical pressure, the transport behavior deviates from Fermi liquid behavior, exhibiting a nearly linear temperature dependence of resistivity with an enhanced pre-factor. Our results shed light on the microscopic origin of the c-axis resistivity peak and provide a clear picture of magnetic energy scale evolution relevant to quantum criticality in UTe2
SWCPC 438 Negatives #5 John B. Slaughter, undated.
No full textThe collection features portraits of sixty-one prominent cattle ranchers, both male and female, who were considered to be the “Cattle Kings of Texas.
SWCPC 438 Negatives #48 F. G. Oxsheer, undated.
No full textThe collection features portraits of sixty-one prominent cattle ranchers, both male and female, who were considered to be the “Cattle Kings of Texas.
SWCPC 438 Negatives #16 John Glenn Halsell, undated.
No full textThe collection features portraits of sixty-one prominent cattle ranchers, both male and female, who were considered to be the “Cattle Kings of Texas.
Portable Cell Tracking Velocimetry for Quantification of Intracellular Fe Concentration of Blood Cells
No full textHematological analysis is crucial for diagnosing and monitoring blood-related disorders. Nevertheless, conventional hematology analyzers remain confined to laboratory settings due to their high cost, substantial space requirements, and maintenance needs. Herein, we present a portable cell tracking velocimetry (CTV) device for the precise measurement of the magnetic susceptibility of biological entities at the single-cell level, focusing on red blood cells (RBCs) in this work. The system integrates a microfluidic channel positioned between permanent magnets that generate a well-defined magnetic field gradient (191.82 TA/mm2). When the cells are injected into the chamber, their particular response to the magnetic field is recorded and used to estimate their properties and quantify their intracellular hemoglobin (Hb) concentration. We successfully track over 400 RBCs per condition using imaging and trajectory analysis, enabling detailed characterizations of their physical and magnetic properties. A comparison of the mean corpuscular hemoglobin measurements revealed a strong correlation between our CTV system and standard ultraviolet–visible (UV-Vis) spectrophotometry (23.1 ± 5.8 pg vs. 22.4 ± 3.9 pg, p > 0.05), validating the accuracy of our measurements. The system’s single-cell resolution reveals population distributions unobtainable through conventional bulk analysis methods. Thus, this portable CTV technology provides a rapid, label-free approach for magnetic cell characterization, offering new possibilities for point-of-care hematological analysis and field-based research applications
SWCPC 438 Negatives #57 Gus L. Ford, undated.
No full textThe collection features portraits of sixty-one prominent cattle ranchers, both male and female, who were considered to be the “Cattle Kings of Texas.
