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Cell size is an important variable in the study of cellular growth, metabolism, and the cell cycle. The large size of "Amoeba proteus" and the ease with which it can be collected and cultured have made it a star in biology education--and it was a model for research on cell biology before the introduction of molecular genetic methods. Measuring the cytoplasmic density of a single amoeba without modern instrumentation seems like a difficult task, but this was done with supreme accuracy in the 1940s. The solution was based on the familiar Cartesian diver that is used to demonstrate Archimedes's principle. It required the fabrication of a tiny diver that would respond to the additional mass of a cell. Experiments using this method allowed investigators to study changes in size and density associated with feeding, starvation, and cell division. This research is an illustration of the ingenuity of cell biologists in the pre-molecular genetic era of their field, which is often overlooked by contemporary scientists. The consideration of the mass, density, and buoyancy of free-living amoebas encourages a new hypothesis about the evolution of testate amoebas.

This study examines the occurrence of humpback whale (Megaptera novaeangliae) song in the northeast Pacific from three years of continuous recordings off central California (36.713°N, 122.186°W). Song is prevalent in this feeding and migratory habitat, spanning nine months of the year (September-May), peaking in winter (November-January), and reaching a maximum of 86% temporal coverage (during November 2017). From the rise of song in fall through the end of peak occurrence in winter, song length increases significantly from month to month. The seasonal peak in song coincides with the seasonal trough in day length and sighting-based evidence of whales leaving Monterey Bay, consistent with seasonal migration. During the seasonal song peak, diel variation shows maximum occurrence at night (69% of the time), decreasing during dawn and dusk (52%), and further decreasing with increasing solar elevation during the day, reaching a minimum near solar noon (30%). Song occurrence increased 44% and 55% between successive years. Sighting data within the acoustic detection range of the hydrophone indicate that variation in local population density was an unlikely cause of this large interannual variation. Hydrographic data and modeling of acoustic transmission indicate that changes in neither habitat occupancy nor acoustic transmission were probable causes. Conversely, the positive interannual trend in song paralleled major ecosystem variations, including similarly large positive trends in wind-driven upwelling, primary productivity, and krill abundance. Further, the lowest song occurrence during the first year coincided with anomalously warm ocean temperatures and an extremely toxic harmful algal bloom that affected whales and other marine mammals in the region. These major ecosystem variations may have influenced the health and behavior of humpback whales during the study period.

The kagome metals AV3Sb5 (A = K, Rb, Cs) present an ideal sandbox to study the interrelation between multiple coexisting correlated phases such as charge order and superconductivity. So far, no consensus on the microscopic nature of these states has been reached as the proposals struggle to explain all their exotic physical properties. Among these, field-switchable electric magneto-chiral anisotropy (eMChA) in CsV3Sb5 provides intriguing evidence for a rewindable electronic chirality, yet the other family members have not been likewise investigated. Here, we present a comparative study of magneto-chiral transport between CsV3Sb5 and KV3Sb5. Despite their similar electronic structure, KV3Sb5 displays negligible eMChA, if any, and with no field switchability. This is in stark contrast to the non-saturating eMChA in CsV3Sb5 even in high fields up to 35 T. In light of their similar band structures, the stark difference in eMChA suggests its origin in the correlated states. Clearly, the V kagome nets alone are not sufficient to describe the physics and the interactions with their environment are crucial in determining the nature of their low-temperature state. [ABSTRACT FROM AUTHOR]

Comparative studies of carpal tunnel release with ultrasound guidance (CTR-US) vs. mini-open CTR (mOCTR) are limited, prompting development of this randomized trial to compare efficacy and safety of these techniques. Patients were randomized (2:1) to CTR-US or mOCTR, treated by experienced hand surgeons (median previous cases: 12 CTR-US; 1000 mOCTR), and followed for 3 months. Among 149 randomized patients, 122 received CTR-US (n = 94) or mOCTR (n = 28). Mean incision length was 6 ± 2 mm in the wrist (CTR-US) vs. 22 ± 7 mm in the palm (mOCTR) (p < 0.001). Median time to return to daily activities (2 vs. 2 days; p = 0.81) and work (3 vs. 4 days; p = 0.61) were similar. Both groups reported statistically significant and clinically important improvements in Boston Carpal Tunnel Questionnaire Symptom Severity and Functional Status Scales, Numeric Pain Scale, and EuroQoL-5 Dimension 5-Level, with no statistical differences between groups. Freedom from wound sensitivity and pain favored CTR-US (61.1% vs. 17.9%; p < 0.001). Adverse event rates were low in each group (2.1% vs. 3.6%; p = 0.55). The efficacy and safety of CTR-US were comparable to mOCTR despite less previous surgical experience with CTR-US. The choice of CTR technique should be determined by shared decision-making between patient and physician. identifier is NCT05405218. [ABSTRACT FROM AUTHOR]

When electric conductors differ from their mirror image, unusual chiral transport coefficients appear that are forbidden in achiral metals, such as a non-linear electric response known as electronic magnetochiral anisotropy (eMChA)1–6. Although chiral transport signatures are allowed by symmetry in many conductors without a centre of inversion, they reach appreciable levels only in rare cases in which an exceptionally strong chiral coupling to the itinerant electrons is present. So far, observations of chiral transport have been limited to materials in which the atomic positions strongly break mirror symmetries. Here, we report chiral transport in the centrosymmetric layered kagome metal CsV3Sb5 observed via second-harmonic generation under an in-plane magnetic field. The eMChA signal becomes significant only at temperatures below T ′ ≈ 35 K, deep within the charge-ordered state of CsV3Sb5 (TCDW ≈ 94 K). This temperature dependence reveals a direct correspondence between electronic chirality, unidirectional charge order7 and spontaneous time-reversal symmetry breaking due to putative orbital loop currents8–10. We show that the chirality is set by the out-of-plane field component and that a transition from left- to right-handed transport can be induced by changing the field sign. CsV3Sb5 is the first material in which strong chiral transport can be controlled and switched by small magnetic field changes, in stark contrast to structurally chiral materials, which is a prerequisite for applications in chiral electronics.Change of chirality from left- to right-handed transport in the layered kagome metal CsV3Sb5 can be controlled by small magnetic field changes, a required feature for chiral electronic applications. [ABSTRACT FROM AUTHOR]

This study combines field structural analysis with thin‐section petrography, U‐Pb dating, and strontium, carbon and oxygen isotopic analysis of calcite fracture fills to constrain the evolution of the 2‐5 km scale paleofluid system around the faulted, plunging fold nose comprising the southern termination of the Gypsum Valley salt wall in the Paradox Basin, U.S.A. Brittle deformation in this region began with the formation of a down‐to‐the‐northeast, counter‐regional fault and then progressed into jointing and faulting in a radial pattern, followed by jointing in a concentric pattern. Coupled with increases in fracture abundance toward the faults, multiple stages of mineralization suggest that the faults served as efficient and long‐lived conduits for vertical fluid migration. Although fracture cement textures and calcite colour are variable throughout the area, the distribution of these characteristics does not correlate with fracture orientation, relative age, stratigraphic or structural position. Irrespective of the type of calcite comprising the fracture cements, δ13C values average near −7‰ (VPDB), whereas δ18O values cluster into groups whose averages are roughly 6‰ apart, with the more negative grouping stratigraphically restricted to fracture cements in Jurassic rocks. The stratigraphic segregation of δ18O values suggests the paleofluid system contained two distinct paleofluids, a more recent one comprised of meteoric waters and an older one comprising brine that originated in Pennsylvanian strata. 87Sr/86Sr ratios in fracture‐filling calcite cements indicate that the older fluid underwent fluid‐rock interaction with Permian strata and that this evolved fluid migrated upwards along the faults until the Triassic or Jurassic. Thereafter, fluid migrating along the faults was more meteoric and appears to have migrated downward along the faults, where it interacted with Permian strata. Consistent U‐Pb dates from carbonates precipitated from the older fluid suggest this stage of the paleofluid system was active around 240 Ma. Local burial history models and published temperatures for fracture cements elsewhere in the basin suggest the younger stage of the paleofluid system occurred during the Latest Cretaceous to Oligocene. This study highlights the spatial and temporal complexity of fluid systems in the vicinity of salt structures and emphasises the need to interpret them through careful integration of high resolution stratigraphic and structural data in the context of evolving salt tectonics. [ABSTRACT FROM AUTHOR]

Cell size is an important variable in the study of cellular growth, metabolism, and the cell cycle. The large size of Amoeba proteus and the ease with which it can be collected and cultured have made it a star in biology education—and it was a model for research on cell biology before the introduction of molecular genetic methods. Measuring the cytoplasmic density of a single amoeba without modern instrumentation seems like a difficult task, but this was done with supreme accuracy in the 1940s. The solution was based on the familiar Cartesian diver that is used to demonstrate Archimedes's principle. It required the fabrication of a tiny diver that would respond to the additional mass of a cell. Experiments using this method allowed investigators to study changes in size and density associated with feeding, starvation, and cell division. This research is an illustration of the ingenuity of cell biologists in the pre-molecular genetic era of their field, which is often overlooked by contemporary scientists. The consideration of the mass, density, and buoyancy of free-living amoebas encourages a new hypothesis about the evolution of testate amoebas. [ABSTRACT FROM AUTHOR]

The interactions between salt diapirs, thrust welds and thrusts in contractional belts are poorly understood due to, first, the inability of seismic data to distinguish between thrusts and welds or resolve associated sub‐resolution deformation, and second, the paucity of good field examples. The Warraweena area in the Northern Flinders Ranges of South Australia contains examples of Neoproterozoic to Early Cambrian squeezed diapirs linked by steep reverse faults formed during the Delamerian Orogeny. Benefiting from good field exposures, we use geological mapping, cross‐section construction and conceptual structural models to assess the three‐dimensional geometry and evolution of the structures, the lateral transition from diapirs to linking faults and the variability of associated meso‐ and small‐scale deformation. Three discrete diapirs consist of narrow outcrops of Callanna Group megabreccia (Willouran in age) up to 5‐km long. Their diapiric origin is confirmed by local development of caprock, steepening of flanking strata in composite halokinetic sequences and reworked diapir and roof debris in adjacent strata. The surrounding rocks display only background levels of small‐scale deformation. In contrast, the linking faults show no evidence of precursor diapirism, have fault‐related anticlines up to 100s of m in wavelength in their hanging walls, and an associated increase in small‐scale deformation (i.e. millimetre to metre scale folds, fractures and shear fabrics). The transitions from diapirs to faults occur within less than 200 m as short thrust welds at the diapir terminations. The exposed structures are analogous to those found on the subsurface of other salt basins such as the Gulf of Mexico and the South Atlantic conjugate margins. The results of this work can aid geoscientists evaluating three‐way traps against squeezed diapirs, welds or faults, and can help them to predict the style and abundance of both halokinetic and small‐scale structures that are below seismic resolution. [ABSTRACT FROM AUTHOR]

Karl Rahner completed his in 1951 but did not receive permission to publish it from his Jesuit superiors. The work appeared in 2004, twenty years after Rahner's death. This essay examines his work on the Assumption and the censors' objections. Rahner's publication of 1947, "On the Theology of Death," was appended to the Marian treatise as an "excursus" but laid the foundation for the later work. Rahner interpreted the Assumption as an anticipation of the resurrection of the dead. This essay focuses on three speculations by Rahner: on the relation of the soul to the body, on the maturation of the soul after death, and on the final resurrection as the world's transformation. The censors criticized Rahner's theology of death as too speculative and his Mariology as too minimal. Yet 's treatment of Mary as a sign of hope until the second coming vindicated Rahner. [ABSTRACT FROM AUTHOR]

This essay traces the history of the Karl Rahner Society between the years 1998 and 2019. It lists the achievements of the society's coordinators, many of the books and articles about Rahner published by members of the society, and the role played in the society by Presidents of the Catholic Theological Society of America. The essay also identifies three persistent themes of the society: Rahner and his contemporaries, Rahner and the Catholic Church, and Rahner and ecumenism. [ABSTRACT FROM AUTHOR]

We conducted numerical simulations of coupled fluid and heat transport in an offshore, buried salt diapir environment to determine the effects of advective heat transport and its relation to the so-called “salt chimney effect.” Model sets were designed to investigate (1) salt geometry, (2) depth-dependent permeability, (3) geologic heterogeneity, and (4) the relative influence of each of these factors. Results show that decreasing the dip of the diapir induces advective heat transfer up the side of the diapir, elevating temperatures in the basin. Depth-dependent permeability causes upwelling of warm waters in the basin, which we show to be more sensitive to basal heat flux than brine concentration. In these model scenarios, heat is advected up the side of the diapir in a narrower zone of upward-flowing warm water, while cool waters away from the diapir flank circulate deeper into the basin. The resulting fluid circulation pattern causes increased discharge at the diapir margin and fluid flow downward, above the crest of the diapir. Geologic heterogeneity decreases the overall effects of advective heat transfer. The presence of low permeability sealing horizons reduces the vertical extent of convection cells, and fluid flow is dominantly up the diapir flank. The combined effects of depth-dependent permeability coupled with geologic heterogeneity simulate several geologic phenomena that are reported in the literature. In this model scenario, conductive heat transfer dominates in the basal units, whereas advection of heat begins to affect the middle layers of the model and dominates the upper units. Convection cells split by sealing layers develop within the upper units. From our highly simplified models, we can predict that advective heat transport (i.e., thermal convection) likely dominates in the early phases of diapirism when sediments have not undergone significant compaction and retain high porosity and permeability. As the salt structures mature into more complex geometries, advection will diminish due to the increase in dip of the salt-sediment interface and the increased hydraulic heterogeneity due to complex stratigraphic architecture. [ABSTRACT FROM AUTHOR]

Karl Rahner and Hans Urs von Balthasar differed in their approaches to Christian soteriology, especially in their understandings of redemption and the cross. These differences stem in part from Rahner’s emphasis on the Trinity in history (the economic Trinity) and Balthasar’s focus on the Trinity’s inner life (the immanent Trinity). While Balthasar’s soteriology better reflects the Church’s official descending Christology, Rahner’s ascending Christology (with its view of Jesus as the fullness of God united to human nature) is the more profound. [ABSTRACT FROM AUTHOR]

Millions of tons of fungal spores are dispersed in the atmosphere every year. These living cells, along with plant spores and pollen grains, may act as nuclei for condensation of water in clouds. Basidiospores released by mushrooms form a significant proportion of these aerosols, particularly above tropical forests. Mushroom spores are discharged from gills by the rapid displacement of a droplet of fluid on the cell surface. This droplet is formed by the condensation of water on the spore surface stimulated by the secretion of mannitol and other hygroscopic sugars. This fluid is carried with the spore during discharge, but evaporates once the spore is airborne. Using environmental electron microscopy, we have demonstrated that droplets reform on spores in humid air. The kinetics of this process suggest that basidiospores are especially effective as nuclei for the formation of large water drops in clouds. Through this mechanism, mushroom spores may promote rainfall in ecosystems that support large populations of ectomycorrhizal and saprotrophic basidiomycetes. Our research heightens interest in the global significance of the fungi and raises additional concerns about the sustainability of forests that depend on heavy precipitation. [ABSTRACT FROM AUTHOR]

The distinctive shapes of basidiomata in the bird's nest fungi reflect differences in the mechanism of splash discharge. In the present study, peridiole discharge was examined in Nidularia pulvinata using high-speed video. Nidularia pulvinata produces globose basidiomata that split open at maturity to expose 100 or more peridioles within a gelatinous matrix. Each peridiole contains an estimated 7 million spores. The impact of water drops splashed the peridioles horizontally from the fruit body, along with globs of mucilage, at a mean velocity of 1.2 m s −1 . Discharged peridioles travelled for a maximum horizontal distance of 1.5 cm. This launch process contrasts with the faster vertical splashes of peridioles over distances of up to one metre from the flute-shaped fruit bodies of bird's nest fungi in the genera Crucibulum and Cyathus . Peridioles in these genera are equipped with a funicular cord that attaches them to vegetation, placing them in an ideal location for ingestion by browsing herbivores. The absence of cords in N. pulvinata and its use of a sloppy discharge mechanism suggest that it is more likely to be dispersed by animals feeding on the forest floor. [ABSTRACT FROM AUTHOR]

The hexagonal superconductor SrPtAs exhibits time-reversal symmetry breaking below Tc, hinting at an unconventional pairing state. Therefore, the symmetry of the underlying crystal is important for the classification of possible gap structures and their mixing. Here, we use the generating point group D6h of SrPtAs for a comprehensive classification of the gap functions and to construct a tight-binding model. Our work clarifies questions of symmetry and topology in this non-symmorphic material and allows a better comparison with other hexagonal systems. [ABSTRACT FROM AUTHOR]

Objectives Complementary and alternative medicine ( CAM) is a diverse collection of approaches used to prevent or treat diseases. The goal of this study was to examine relationships between dental patient characteristics and current usage of CAM therapies. Methods The CAM definition encompassed 24 therapies excluding prayer. Associations and trends in usage were assessed for gender, income, education, and age. Multivariable logistic and negative binomial models were used to identify factors impacting the use and number of CAM therapies used. Results In dental patients ( n = 402), nearly 67 percent of subjects reported at least one CAM treatment. Gender was significantly associated with recent utilization of CAM, biological, manipulative (all P < 0.01), and mind-body ( P = 0.04) therapies, as well as the number ( P < 0.01) of therapies used. Higher education levels were significant in usage of any CAM, biological, and mind-body therapies ( P < 0.01). Conclusion A large proportion of dental patients reported use of CAM therapies. While CAM therapies and those who use them are diverse, given their widespread use, they clearly have potential impacts on the oral health of the public. Knowledge of the characteristics of dental patients who use CAM therapies is a first step in developing a broader understanding how CAM therapies and associated beliefs may affect oral health and public health programs. [ABSTRACT FROM AUTHOR]

For the database bibnet.org we have implemented a filter function to allow searches within the local holdings of an institution. To make this happen, we encoded KBART holding information into the reference of each article.

Traditionally, in three dimensions, the only symmetries essential for superconductivity are time reversal (T) and inversion (I). Here, we examine superconductivity in two dimensions and find that T and I are not required, and having a combination of either symmetry with a mirror operation (Mz) on the basal plane is sufficient. By combining energetic and topological arguments, we classify superconducting states when T and I are not present, a situation encountered in several experimentally relevant systems, such as transition metal dichalcogenides or a two-dimensional Rashba system, when subject to an applied field, and in superconducting monolayer FeSe with Néel antiferromagnetic order. Energetic arguments suggest interesting superconducting states arise. For example, we find a unique pure intraband pairing state with Majorana chiral edge states in Néel-ordered FeSe. Employing topological arguments, we find when the only symmetry is the combination of I with Mz, the superconducting states are generically fully gapped and can have topologically protected chiral Majorana edge modes. In all other cases, there are no chiral Majorana edge states, but the superconducting bulk can have point nodes with associated topologically protected flatband Majorana edge modes. Our analysis provides guidance on the design and search for novel two-dimensional superconductors and superconducting heterostructures. [ABSTRACT FROM AUTHOR]

Theoretically, it has been known that breaking spin degeneracy and effectively realizing spinless fermions is a promising path to topological superconductors. Yet, topological superconductors are rare to date. Here we propose to realize spinless fermions by splitting the spin degeneracy in momentum space. Specifically, we identify monolayer hole-doped transition metal dichalcogenide (TMD)s as candidates for topological superconductors out of such momentum-space-split spinless fermions. Although electron-doped TMDs have recently been found superconducting, the observed superconductivity is unlikely topological because of the near spin degeneracy. Meanwhile, hole-doped TMDs with momentum-space-split spinless fermions remain unexplored. Employing a renormalization group analysis, we propose that the unusual spin-valley locking in hole-doped TMDs together with repulsive interactions selectively favours two topological superconducting states: interpocket paired state with Chern number 2 and intrapocket paired state with finite pair momentum. A confirmation of our predictions will open up possibilities for manipulating topological superconductors on the device-friendly platform of monolayer TMDs. [ABSTRACT FROM AUTHOR]

Coupling a many-body-localized system to a dissipative bath necessarily leads to delocalization. Here, we investigate the nature of the ensuing relaxation dynamics and the information it holds on the many-body-localized state. We formulate the relevant Lindblad equation in terms of the local integrals of motion of the underlying localized Hamiltonian. This allows us to map the quantum evolution deep in the localized state to tractable classical rate equations. We consider two different types of dissipation relevant to systems of ultracold atoms: dephasing due to inelastic scattering on the lattice lasers and particle loss. Our approach allows us to characterize their different effects in the limiting cases of weak and strong interactions. [ABSTRACT FROM AUTHOR]

Heterostructures utilizing topological insulators exhibit a remarkable spin-torque efficiency. However, the exact origin of the strong torque, in particular whether it stems from the spin-momentum locking of the topological surface states or rather from spin-Hall physics of the topological-insulator bulk, remains unclear. Here, we explore a mechanism of spin-torque generation purely based on the topological surface states. We consider topological-insulator-based bilayers involving ferromagnetic metal (TI/FM) and magnetically doped topological insulators (TI/mdTI), respectively. By ascribing the key theoretical differences between the two setups to location and number of active surface states, we describe both setups within the same framework of spin diffusion of the nonequilibrium spin density of the topological surface states. For the TI/FM bilayer, we find large spin-torque efficiencies of roughly equal magnitude for both in-plane and out-of-plane spin torques. For the TI/mdTI bilayer, we elucidate the dominance of the spin-transfer-like torque. However, we cannot explain the orders of magnitude enhancement reported. Nevertheless, our model gives an intuitive picture of spin-torque generation in topological-insulator-based bilayers and provides theoretical constraints on spin-torque generation due to topological surface states. [ABSTRACT FROM AUTHOR]

For a tetragonal material, order parameters of px and py symmetry are related by rotation and hence have the same Tc at a mean-field level. This degeneracy can be lifted by a symmetry-breaking field, such as (uniaxial) in-plane strain, such that at Tc, the order parameter is only of px or py symmetry. Only at a lower temperature also the respective other order parameter condenses to form a chiral p-wave state. At the mean-field level, the derivative of Tc with strain is discontinuous at zero strain. We analyze the consequences of (thermal) fluctuations on the strain-temperature phase diagram within a Ginzburg-Landau approach. We find that the order-parameter fluctuations can drive the transition to be weakly first order, rounding off this discontinuity. We discuss the possibility of a second-order transition into a nonsuperconducting time-reversal-symmetry-breaking phase and consequences for the spin-triplet superconductor Sr2RuO4. [ABSTRACT FROM AUTHOR]

The fluid system within a critically tapering orogenic wedge is governed by complex interactions between topographic drive, thermal gradients, prograde dehydration reactions, internal structure, and regional tectonic compaction. Despite this complexity, topography is widely known to be the primary driving potential responsible for basin-scale fluid migration within the upper 7-10 km of an orogenic wedge. In recent years, investigators have revisited the problem of basin-scale fluid flow with an emphasis on depth-decaying permeability, which is a geologic phenomenon that is seldom accounted for in regional flow models. These recent investigations have shown that depth-dependent permeability at the basin scale strongly influences the relationship between local- and regional-scale flow paths. Here we investigate topography driven fluid flow within an orogenic wedge using a numerical modeling experiment designed to assess first-order fluid system behavior when permeability decreases systematically with depth. Critical taper theory is invoked to define two-dimensional basin geometry, and three subaerially exposed orogenic wedge models are presented with critical taper angles of 2°, 4°, and 10°. To assess the combined influence of topographic slope and depth-dependent permeability, a constant rate infiltration is applied at the wedge surface and a transient simulation is performed within each model for 20 m.y. Our results suggest that (1) depth-dependent permeability severely limits the penetration depth of infiltrating water within broadly tapering orogenic wedge systems, (2) fluid system evolution within a narrowly tapering orogenic wedge (i.e., ≤2°) is governed by local-scale topography superimposed on the regional gradient, (3) the influence of subbasin topography on local-scale fluid circulation is suppressed as the regional topographic gradient increases, and (4) the spatial distribution of groundwater residence time is fundamentally different when topographic slope exceeds 3°. [ABSTRACT FROM AUTHOR]

Much interest in the superconducting proximity effect in three-dimensional (3D) topological insulators (TIs) has been driven by the potential to induce Majorana bound states at the interface. Most candidate materials for 3D TI, however, are bulk metals, with bulk states at the Fermi level coexisting with well-defined surface states exhibiting spin-momentum locking. In such topological metals, the proximity effect can differ qualitatively from that in TIs. By studying a model topological metal-superconductor (TM-SC) heterostructure within the Bogoliubov-de Gennes formalism, we show that the pair amplitude reaches the naked surface, unlike in a topological insulator-superconductor (TI-SC) heterostructure where it is confined to the interface. Furthermore, we predict vortex-bound-state spectra to contain a Majorana zero mode localized at the naked surface, separated from the bulk vortex-bound-state spectra by a finite energy gap in such a TM-SC heterostructure. These nakedsurface- bound modes are amenable to experimental observation and manipulation, presenting advantages of TM-SC over TI-SC. [ABSTRACT FROM AUTHOR]

Background: Numerous studies have investigated the importance of visual clarity in simulated athletic performance and, surprisingly, have observed that several sports-related tasks are resilient to low-tomoderate levels of retinal defocus. The purpose of this study was to determine the effect of myopic defocus on baseball batting performance, as well as the influence of gender, preferred hand, refractive error, and previous baseball experience. Methods: Thirty visually normal (visual acuity at least 20/20, stereoacuity better than 50 arc seconds of stereoacuity) young-adult participants were pitched 20 baseballs from a pitching machine under four conditions in a randomized order: plano (control), +1.00 D, +2.00 D, and +3.00 D. All participants were tested under binocular viewing conditions, with their habitual distance correction in place. Two independent observers graded the batting performance via a quality-of-contact score. Results: Batting performance was significantly reduced under +2.00 D and +3.00 D conditions, but not under the +1.00 D condition. The overall effect of retinal defocus was significant (F = 9.137, p < 0.001). Previous baseball experience yielded a statistically significant difference in performance, but neither refractive error, hand, order, nor gender significantly influenced performance. A high linear correlation between both observers was found (R2 = 0.99). Conclusion: This study demonstrated that baseball batting performance was resilient to low levels of retinal defocus for amateur baseball players. The threshold level of myopic defocus where performance declined appears to be lower for baseball than for other simulated sportsrelated activities in the literature, including golf putting, cricket batting, and basketball free throws, suggesting that the influence of myopic defocus on athletic performance is likely task-dependent. [ABSTRACT FROM AUTHOR]

The modern understanding of topological insulators is based on Wannier obstructions in position space. Motivated by this insight, we study topological superconductors from a position-space perspective. For a one-dimensional superconductor, we show that the wave function of an individual Cooper pair decays exponentially with separation in the trivial phase and polynomially in the topological phase. For the position-space Majorana representation, we show that the topological phase is characterized by a nonzero Majorana polarization, which captures an irremovable and quantized separation of Majorana Wannier centers from the atomic positions. We apply our results to diagnose second-order topological superconducting phases in two dimensions. Our work establishes a vantage point for the generalization of topological quantum chemistry to superconductivity. [ABSTRACT FROM AUTHOR]