Dynamics of Transformation from Segregation to Mixed Wealth Cities

We model the dynamics of the Schelling model for agents described simply by a continuously distributed variable - wealth. Agents move to neighborhoods where their wealth is not lesser than that of some proportion of their neighbors, the threshold level. As in the case of the classic Schelling model where segregation obtains between two races, we find here that wealth-based segregation occurs and persists. However, introducing uncertainty into the decision to move - that is, with some probability, if agents are allowed to move even though the threshold level condition is contravened - we find that even for small proportions of such disallowed moves, the dynamics no longer yield segregation but instead sharply transition into a persistent mixed wealth distribution. We investigate the nature of this sharp transformation between segregated and mixed states, and find that it is because of a non-linear relationship between allowed moves and disallowed moves. For small increases in disallowed moves, there is a rapid corresponding increase in allowed moves, but this tapers off as the fraction of disallowed moves increase further and finally settles at a stable value, remaining invariant to any further increase in disallowed moves. It is the overall effect of the dynamics in the initial region (with small numbers of disallowed moves) that shifts the system away from a state of segregation rapidly to a mixed wealth state. The contravention of the tolerance condition could be interpreted as public policy interventions like minimal levels of social housing or housing benefit transfers to poorer households. Our finding therefore suggests that it might require only very limited levels of such public intervention - just sufficient to enable a small fraction of disallowed moves, because the dynamics generated by such moves could spur the transformation from a segregated to mixed equilibrium.Comment: 12 pages, 7 figure

Economic evaluation of multiplex ligation-dependent probe amplification and karyotyping in prenatal diagnosis: a cost-minimization analysis

textabstractPurpose: To assess the cost-effectiveness of Multiplex Ligation-dependent Probe Amplification (MLPA, P095 kit) compared to karyotyping. Methods: A cost-minimization analysis alongside a nationwide prospective clinical study of 4,585 women undergoing amniocentesis on behalf of their age (≥36 years), an increased risk following first trimester prenatal screening or parental anxiety. Results: Diagnostic accuracy of MLPA (P095 kit) was comparable to karyotyping (1.0 95% CI 0.999-1.0). Health-related quality of life did not differ between the strategies (summary physical health: mean difference 0.31, p = 0.82; summary mental health: mean difference 1.91, p = 0.22). Short-term costs were lower for MLPA: mean difference €315.68 (bootstrap 95% CI €315.63-315.74; -44.4%). The long-term costs were slightly higher for MLPA: mean difference €76.42 (bootstrap 95% CI €71.32-81.52; +8.6%). Total costs were on average €240.13 (bootstrap 95% CI €235.02-245.23; -14.9%) lower in favor of MLPA. Cost differences were sensitive to proportion of terminated pregnancies, sample throughput, individual choice and performance of tests in one laboratory, but not to failure rate or the exclusion of polluted samples. Conclusion: From an economic perspective, MLPA is the preferred prenatal diagnostic strategy in women who undergo amniocentesis on behalf of their age, following prenatal screening or parental anxiety

Loss-of-function mutations in the X-linked biglycan gene cause a severe syndromic form of thoracic aortic aneurysms and dissections.

Thoracic aortic aneurysm and dissection (TAAD) is typically inherited in an autosomal dominant manner, but rare X-linked families have been described. So far, the only known X-linked gene is FLNA, which is associated with the periventricular nodular heterotopia type of Ehlers-Danlos syndrome. However, mutations in this gene explain only a small number of X-linked TAAD families. We performed targeted resequencing of 368 candidate genes in a cohort of 11 molecularly unexplained Marfan probands. Subsequently, Sanger sequencing of BGN in 360 male and 155 female molecularly unexplained TAAD probands was performed. We found five individuals with loss-of-function mutations in BGN encoding the small leucine-rich proteoglycan biglycan. The clinical phenotype is characterized by early-onset aortic aneurysm and dissection. Other recurrent findings include hypertelorism, pectus deformity, joint hypermobility, contractures, and mild skeletal dysplasia. Fluorescent staining revealed an increase in TGF-β signaling, evidenced by an increase in nuclear pSMAD2 in the aortic wall. Our results are in line with those of prior reports demonstrating that Bgn-deficient male BALB/cA mice die from aortic rupture. In conclusion, BGN gene defects in humans cause an X-linked syndromic form of severe TAAD that is associated with preservation of elastic fibers and increased TGF-β signaling.Genet Med 19 4, 386-395

International Consensus Statement on Rhinology and Allergy: Rhinosinusitis

Background: The 5 years since the publication of the first International Consensus Statement on Allergy and Rhinology: Rhinosinusitis (ICAR‐RS) has witnessed foundational progress in our understanding and treatment of rhinologic disease. These advances are reflected within the more than 40 new topics covered within the ICAR‐RS‐2021 as well as updates to the original 140 topics. This executive summary consolidates the evidence‐based findings of the document. Methods: ICAR‐RS presents over 180 topics in the forms of evidence‐based reviews with recommendations (EBRRs), evidence‐based reviews, and literature reviews. The highest grade structured recommendations of the EBRR sections are summarized in this executive summary. Results: ICAR‐RS‐2021 covers 22 topics regarding the medical management of RS, which are grade A/B and are presented in the executive summary. Additionally, 4 topics regarding the surgical management of RS are grade A/B and are presented in the executive summary. Finally, a comprehensive evidence‐based management algorithm is provided. Conclusion: This ICAR‐RS‐2021 executive summary provides a compilation of the evidence‐based recommendations for medical and surgical treatment of the most common forms of RS