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Dental dimorphism is one of the primary means by which the mating systems of extinct hominins are studied. Its use has been particularly significant for describing the behaviors of Australopithecus and early Homo, and consequently the factors involved in the evolution of our own species. Analysis however, has tended to produce ambiguous and contrasting results, with no firm agreement as to what mating strategies these genera practiced. Interpretation is confounded by numerous problems such as a generally poor understanding of how dental dimorphism develops in primates, and what factors influence its expression. It is also not well known how these factors interact with different aspects of the dentition and to what relative extent these aspects are diagnostic of mating behavior. The failure in many cases to firmly establish the sex of fossil specimens has likewise hampered the interpretations of sexual dimorphism and by extension, mating behavior. Lastly, the ability to correlate dental dimorphism with mating systems, even in living primates, has met with only moderate success. For these reasons it is argued that dental dimorphism be used only to support the most general assertions about hominin social behavior.

[EN] Let (T(t))t>0 be a strongly continuous C0-semigroup of bounded linear operators on a Banach space X such that limt→∞ kT(t)/tk = 0. Characterizations of when (T(t))t>0 is uniformly mean ergodic, i.e., of when its Cesàro means r−1 R r 0 T(s) ds converge in operator norm as r → ∞, are known. For instance, this is so if and only if the infinitesimal generator A has closed range in X if and only if limλ↓0+ λR(λ, A) exists in the operator norm topology (where R(λ, A) is the resolvent operator of A at λ). These characterizations, and others, are shown to remain valid in the class of quojection Fréchet spaces, which includes all Banach spaces, countable products of Banach spaces, and many more. It is shown that the extension fails to hold for all Fréchet spaces. Applications of the results to concrete examples of C0-semigroups in particular Fréchet function and sequence spaces are presented, The second author was partially supported by MEC and FEDER Project MTM 2010-15200, GV Project PrometeoII/2013/013 and the net MTM 2007–30904–E (Spain).

For C-0-semigroups of continuous linear operators acting in a Banach space criteria are available which are equivalent to uniform mean ergodicity of the semigroup, meaning the existence of the limit (in the operator norm) of the Cesaro or Abel averages of the semigroup. Best known, perhaps, are criteria due to Lin, in terms of the range of the infinitesimal generator A being a closed subspace or, whether 0 belongs to the resolvent set of A or is a simple pole of the resolvent map lambda -> (lambda-A)(-1). It is shown in the setting of locally convex spaces (even in Frechet spaces), that neither of these criteria remain equivalent to uniform ergodicity of the semigroup (i.e., the averages should now converge for the topology of uniform convergence on bounded sets). Our aim is to exhibit new results dealing with uniform mean ergodicity of C-0-semigroups in more general spaces. A characterization of when a complete, barrelled space with a basis is Montel, in terms of uniform mean ergodicity of certain C-0-semigroups acting in the space, is also presented.

A 23-year-old man experiencing three episodes of acute pancreatitis of undetermined etiology is described. Repeated questioning revealed that all three events had occurred after intake of the drug pyritinol. Controlled rechallenge with a single dose of the drug led to a fourth episode of acute pancreatitis. Skin testing was negative, but lymphocyte stimulation tests and double fluorescence analysis detected pyritinol-activated CD4 and CD8 lymphocytes. Together with the clinical observation that the intervals between drug intake and start of symptoms of acute pancreatitis became shorter with repeated exposure, the data are consistent with an immune-mediated origin of the pancreatitis. Pyritinol has to be added to the list of drugs capable of inducing acute pancreatitis.

Immune-mediated adverse reactions to drugs are often due to T-cell reactivity, and cross-reactivity is an important problem in pharmacotherapy.We investigated whether chemical inert drugs can stimulate T cells through their T-cell receptor (TCR) and analyzed the cross-reactivities to related compounds.We transfected human TCRs isolated from two drug-reactive T-cell clones (TCCs) by PCR into a TCR-negative mouse T-cell hybridoma. The TCCs were isolated from a patient with drug hypersensitivity to the antibacterial sulfonamide sulfamethoxazole (SMX).The transfectants reacted to SMX only in the presence of antigen-presenting cells (APCs). Glutaraldehyde-fixed APCs, however, were sufficient to elicit T-cell stimulation, indicating a processing-independent direct interaction of the drug with the TCR and MHC molecule. The transfected hybridomas secreted IL-2 in a drug dose-dependent manner, whereas the degree of reactivity was dependent on the level of TCR expression. One transfectant reacted not only to SMX but also to related sulfonamide compounds. Interestingly, high TCR expression increased cross-reactivity to other structurally related compounds. In addition, SMX-specific TCR cross-reacted only with sulfonamides bearing a sulfanilamide core structure but not with sulfonamides such as celecoxib, furosemide, or glibenclamide.These results demonstrate that the T-cell reactivity to drugs is solely determined by the TCR. Moreover, these results show that cross-reactivity of structurally similar compounds correlates with the density of the TCR. Stably transfected T-cell hybridomas may represent a powerful screening tool for cross-reactivity of newly generated sulfonamide-containing compounds such as celecoxib.