Random patterns of lanthanide(III) ion–doped zeolites were used to create a tamper-proof optical authentication system.

Europium(iii) dipicolinate complexes have been a model system in lanthanide solution chemistry for decades, here it is investigated in unprecedented detail.

ObjectiveTo compare results of obese patients with knee osteoarthritis (OA) who, after an intensive weight loss regimen, received 1 year of either dietary support (D), a knee-exercise program (E), or “no attention” (C; control group).MethodsWe conducted a randomized, 2-phase, parallel-group trial. A total of 192 obese participants with knee OA were enrolled; the mean age was 62.5 years and 81% were women with a mean entry weight of 103.2 kg. In phase 1, all participants were randomly assigned to 1 of 3 groups and began a dietary regimen of 400–810 and 1,250 kcal/day for 16 weeks (2 8-week phases) to achieve a major weight loss. Phase 2 consisted of 52 weeks' maintenance in either group D, E, or C. Outcomes were changes from randomization in pain on a 100-mm visual analog scale, weight, and response according to the Outcome Measures in Rheumatology-Osteoarthritis Research Society International criteria.ResultsMean weight loss for phase 1 was 12.8 kg. After 1 year on maintenance therapy, the D group sustained a lower weight (11.0 kg, 95% confidence interval [95% CI] 9.0, 12.8 kg) than those in the E (6.2, 95% CI 4.4, 8.1 kg) and C (8.2, 95% CI 6.4, 10.1 kg) groups (P = 0.002 by analysis of covariance [ANCOVA]). Adherence was low in the E group. All groups had statistically significant pain reduction (D: 6.1; E: 5.6; and C: 5.5 mm) with no difference between groups (P = 0.98 by ANCOVA). In each group 32 (50%), 26 (41%), and 33 (52%) participants responded to treatment in the D, E, and C groups, respectively, with no statistically significant difference in the number of responders (P = 0.41).ConclusionA significant weight reduction with a 1-year maintenance program improves knee OA symptoms irrespective of maintenance program.

Counterfeit consumer products, electronic components, and medicines generate heavy economic losses, pose a massive security risk, and endanger human lives on a daily basis. Combatting counterfeits requires incorporation of uncopiable or unclonable features in each and every product. By exploiting the inherent randomness of stochastic processes, an optical authentication system based on physical unclonable functions (PUFs) was developed. The system relies on placing unique tagsPUF-tagson the individual products. The tags can be created using commercial printing and coating technologies using several combinations of carrier materials and taggant materials. The authentication system was found to be independent of how contrast was generated, and examples of PUF-tags based on scattering, absorption, and luminescence were made. A version of the authentication using the combination of scattering-based PUF-tags and a smartphone-based reader was validated on a sample size of 9720 unique codes. With zero false positives in 29 154 matches, an encoding capacity of 2.5 × 10 120 , and a low cost of manufacture, the scattering-based authentication system was found to have the potential to solve the problem of counterfeit products.

The physicochemical properties of lanthanide-(III) ions are directly linked to the structure of the surrounding ligands. Rapid ligand exchange prohibits direct structure−property relationships from being formed for simple complexes in solution because the property measured will be an average over several structures. For kinetically inert lanthanide(III) complexes, the simpler speciation may alleviate the problem, yet the archetypical complexes formed by ligands derived from cyclen are known to have at least four different forms in solutioneach with a variation in the crystal field that gives rise to significantly different properties. Slow interchange between forms has been engineered, so that a single complex geometry can be studied, but fast or intermediate interchange between forms is much more commonly observed. The rapid structural fluctuation can report on the changing chemical environment and can be disregarded if a specific property of a lanthanide(III) complex is exploited in an application. However, if we are to understand the chemistry of the lanthanide(III) ions in solution, we must include the structural fluctuation that takes place even in kinetically inert lanthanide(III) complexes in our studies. Here, we have scrutinized the processes that determine the speciation of lanthanide(III) complexes of 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetate (DOTA)-like ligands, in particular the processes that enable exchange between forms that have different physicochemical properties, exemplified by the exchange between the diastereomeric capped square-antiprismatic (cSAP) and capped twisted-square-antiprismatic (cTSAP) forms of DOTA-like lanthanide(III) complexes. In the characterization of a kinetically inert f-element complex, understanding the structural fluctuation in the system is critical because a single observed property can arise from a weighted average, from all forms present, or from a single form with a dominating contribution. Further, the experimental condition will influence both the distribution of lanthanide(III) species in solution and the rates of the processes that change the coordination sphere of the lanthanide(III) ions. This is highlighted using data from a series of cyclen-derived ligands with different pendant arms and different denticity. The data were obtained in experiments that take place on different time scales to show that the rate of the process that results in a structural change must be considered against the time of the experiment. We conclude that the structural fluctuations must be taken into account and that they cannot be predicted from the ligand structure. Thus, an estimate of the exchange rates between forms, the relative concentrations of the specific forms, and the effect of the specific structure of each form of the complex must be included in the description of the solution properties of f-element chelates.