ABSTRACT We present a formulation of the immersed boundary method for incompressible flows over bodies with surface slip described by the Navier boundary condition. In the present method, the wall slip velocity and the boundary force are implicitly determined through a projection that enforces both the boundary conditions and the divergence‐free constraint of the velocity field. The present method is first‐order accurate in space and fourth‐order accurate in time, providing a consistent way to evaluate the velocity gradient on the boundary, which is challenging in conventional continuous forcing approaches. The validation results from the simulation of the flow past two‐dimensional stationary and moving bodies are in good agreement with previous experimental and numerical results for a wide range of slip lengths on the surface, including the no‐slip case. The spatial resolution required to reproduce the body‐fitted mesh solution is numerically evaluated for Reynolds numbers below 100, where the wall slip velocity plays an important role.
Standard DSGE solution practice closes forward-looking equilibrium problems by combining model specification with criteria that select one operational equilibrium from multiple candidate paths, yet this closure step typically remains implicit. This paper formalizes that closure step as a substantive operation in standard DSGE solution practice. By separating the economic specification (S), the self-referential operator (T), and the equilibrium selection rule (Π), the (S, T, Π) triad provides a descriptive semantic grammar for comparing closure choices across familiar solution environments. The framework clarifies what standard solver diagnostics actually report, captures the regime-iteration logic of piecewise-linear methods like OccBin, explains why independent linear solvers often reproduce the same selected equilibrium, and distinguishes within-model refinements from specification-augmenting closure changes under indeterminacy.
. Bowden, Hensel, and Webb constructed infinitely many quasi-mophisms on the diffeomorphism groups of orientable surfaces. In this paper, we extend their result to nonorientable surfaces. Namely, we prove that the space of nontrivial quasimorphisms g QH (Diff 0 ( N g )) on the identity component of the diffeomorphism group Diff 0 ( N g ) on a closed nonorientable surface N g of genus g ≥ 3 is infinite dimensional. As a corollary, we obtain the unbound-edness of the commutator length and the fragmentation length on Diff 0 ( N g ).
Margarine, a water-in-oil (W/O) emulsion, offers advantages such as lower costs in comparison to similar products, but large amounts of saturated fats pose health risks. Reduction of saturated fat content is difficult and often leads to “oil-off,” i.e., the seepage of liquid oil from the mixture, resulting in undesirable appearance and texture. Investigations into the phenomenon have often focused on morphology at the water-oil interfaces, and this work establishes Raman imaging as a powerful application for observing microscopic morphologies of W/O emulsions. We analyze morphologies of 5 distinct margarine spreads that differ in manufacturing date, formulation, and manufacturing process. More robust H-bonding in the oil phase of the emulsions co-occurred with smaller amounts of oil-off, suggesting that H-bonding interactions between emulsifier molecules, water, and crystallized fats in the lipid phase of the W/O emulsions results in an emulsion that is less susceptible to the production of oil-off.
Compared to adults, prepubertal children exhibit underdeveloped cholinergic sweating. How maturation affects cholinergic sweating through early adulthood remains unclear. We assessed the influence of age and sex on cholinergic sweating, including seasonal acclimatization, in groups of prepubescent to young adult males and females. A total of 405 children and adolescents (ages 6-17; 229 boys and 176 girls) and 52 young adults (ages 18-25; 25 males and 27 females) underwent pilocarpine iontophoresis on the ventral forearm to induce cholinergic sweating during summer (n = 111) and non-summer (n = 457). Sweat gland output, calculated as sweat rate divided by activated sweat gland density, was compared between sexes and across age groups in 2-year intervals until age 17. We observed statistically significant sex-related differences in sweat gland output in children as young as 8-9 years of age, with even greater differences between sexes in groups 14-15 years of age and older. The changes in cholinergic sweating function occurred independently of maturational changes in body morphology. Our results offer insight into the sex differences in cholinergic sweating activity during maturation from childhood to adolescence.
