Workers' compensation in the United States: high costs, low benefits

Studies suggest that income replacement is low for many workers with serious occupational injuries and illnesses. This review discusses three areas that hold promise for raising benefits to workers while reducing workers' compensation costs to employers: improving safety, containing medical costs, and reducing litigation. In theory, workers' compensation increases the costs to employers of injuries and so provides incentives to improve safety. Yet, taken as a whole, research does not provide convincing evidence that workers' compensation reduces injury rates. Moreover, unlike safety and health regulation, workers' compensation focuses the attention of employers on individual workers. High costs may lead employers to discourage claims and litigate when claims are filed. Controlling medical costs can reduce workers' compensation costs. Most studies, however, have focused on costs and have not addressed the effectiveness of medical care or patient satisfaction. Research also has shown that workers' compensation systems can reduce the need for litigation. Without litigation, benefits can be delivered more quickly and at lower costs

Non-triviality of the MM-degree of the AA-polynomial

This note gives a proof that the $A$-polynomial of any nontrivial knot in $S^3$ has nontrivial $M$-degree.Comment: 5 page

The UK social security system for self-employed people

The UK system for social insurance has evolved over the past sixty years in response to both changes in government policy and changing social circumstances. The current system has moved away somewhat from the old Welfare State principles. The current social insurance system in the UK is targeted at supporting people in work to make work pay, is largely non-universal, emphasises personal provision (especially in areas such as old age pensions) and is means-tested. Self-employed people form a significant part of the UK labour force, perhaps largely as a result of government policy that has encouraged such a restructuring of the labour market. Self-employed people in the UK are an extremely heterogeneous group and also exhibit important differences in characteristics compared with employees. Self-employed people are more likely to be less well off financially and to be older than employees. -- Das britische System der Sozialversicherung hat sich in den vergangenen sechzig Jahren sowohl in Reaktion auf Änderungen in der Regierungspolitik als auch auf den sozialen Wandel entwickelt. Das gegenwärtige System hat sich dadurch von den ursprünglichen Wohlfahrtsstaatsprinzipen entfernt. Es zielt darauf ab, nach dem Prinzip, dass sich Arbeit lohnen soll (make work pay) Menschen in Beschäftigung zu bringen, es ist in hohem Maße nichtuniversalistisch, es betont persönlich geleistete Beiträge (besonders in Bereichen wie der Altersvorsorge) und es basiert auf Bedürftigkeitsprüfungen. Selbstständige stellen einen bedeutenden Teil der Erwerbstätigen im Vereinigten Königreich dar. Dies ist möglicherweise auch Folge einer Beschäftigungspolitik, welche die Restrukturierung des Arbeitsmarktes in dieser Weise gefördert hat. Selbstständige sind eine sehr heterogene Gruppe und sie weisen im Vergleich zu den abhängig Beschäftigten deutliche Unterschiede auf. So sind Selbstständige finanziell eher schlechter gestellt und älter als abhängig Beschäftigte.

Metabelian SL(n,C) representations of knot groups IV: twisted Alexander polynomials

In this paper we will study properties of twisted Alexander polynomials of knots corresponding to metabelian representations. In particular we answer a question of Wada about the twisted Alexander polynomial associated to the tensor product of two representations, and we settle several conjectures of Hirasawa and Murasugi

The SL(2,C) Casson invariant for Dehn surgeries on two-bridge knots

We investigate the behavior of the SL(2,C) Casson invariant for 3-manifolds obtained by Dehn surgery along two-bridge knots. Using the results of Hatcher and Thurston, and also results of Ohtsuki, we outline how to compute the Culler--Shalen seminorms, and we illustrate this approach by providing explicit computations for double twist knots. We then apply the surgery formula of Curtis to deduce the SL(2,C) Casson invariant for the 3-manifolds obtained by p/q-Dehn surgery on such knots. These results are applied to prove nontriviality of the SL(2,C) Casson invariant for nearly all 3-manifolds obtained by nontrivial Dehn surgery on a hyperbolic two-bridge knot. We relate the formulas derived to degrees of A-polynomials and use this information to identify factors of higher multiplicity in the $\hat{A}$-polynomial, which is the A-polynomial with multiplicities as defined by Boyer-Zhang.Comment: 32 pages, 2 figures, to be published in Algebraic and Geometric Topolog

Public health risk of Giardia and Cryptosporidium posed by reintroduction of beavers into Scotland

Following publication of ‘Scottish Beaver Trial Independent Public Health Monitoring 2009-2014 Report and Recommendations’ (Mackie, 2014), two pieces of complementary work were undertaken in parallel to assess the potential contribution of reintroduced beavers in Scotland to the public health burden of disease attributed to Giardia spp. and Cryptosporidium spp. parasites. The first, a risk assessment, addressing the question ‘What is the likelihood that re-introduced beavers will have a significant impact on the contamination of drinking water supplies with Cryptosporidium parvum and Giardia lamblia?’ (Appendix 1), was conducted by Scottish Government’s Centre of Expertise on Animal Disease Outbreaks (EPIC). This reviewed evidence from data and publications across the world, as well as evidence from the beaver trial and SNH’s Tayside beaver reports, and used this to assess the likely additional contribution of beavers to the risk associated with exposure to these parasites in Scotland. The second, ‘What is the likelihood that beavers will be an important source of contamination of drinking water supplies with Cryptosporidium parvum and Giardia intestinalis?’ (Appendix 2), was prepared by Health Protection Scotland (HPS), Scottish Parasite Diagnostic Reference Laboratory (SPDL) and Drinking Water Quality Regulator for Scotland (DWQR). This reviewed the diagnostics, surveillance and epidemiology of these infections in people in Scotland