We are developing synthetic polymers for pharmaceutical and medical applications. These applications can be broadly grouped on how the polymer will be utilized e.g. material, excipient or molecule. Our focus is to develop polymers with more defined structures that are based on biological, physicochemical and/or materials criteria. Strategies are being developed to more efficiently optimize structure-property correlations during preclinical development. We describe two examples of our research on pharmaceutical polymer development: narrow molecular weight distribution (MWD) homopolymeric precursors which can be functionalized to give families of narrow MWD homo- and co-polymers, and hydrolytically degradable polymers.

Background: Headaches have not only medical but also great socioeconomic significance, therefore, it is necessary to evaluate the overall impact of headaches on a patient’s life, including their work and work efficiency. The aim of this study was to determine the impact of individual headache types on work and work efficiency. Methods: This research was designed as a cross-sectional study performed by administering a questionnaire among employees. The questionnaire consisted of general questions, questions about headache features, and questions about the impact of headaches on work. Results: Monthly absence from work was mostly represented by migraine sufferers (7.1%), significantly more than with sufferers with tension-type headaches (2.23%; p = 0.019) and other headache types (2.15%; p = 0.025). Migraine sufferers (30.2%) worked in spite of a headache for more than 25 h, which was more frequent than with sufferers from tension-type and other-type headaches (13.4%). On average, headache sufferers reported work efficiency ranging from 66% to 90%. With regard to individual headache types, this range was significantly more frequent in subjects with tension-type headaches, whereas 91–100% efficiency was significantly more frequent in subjects with other headache types. Lower efficiency, i.e., 0–40% and 41–65%, was significantly more frequent with migraine sufferers. Conclusions: Headaches, especially migraines, significantly affect the work and work efficiency of headache sufferers by reducing their productivity. Loss is greater due to reduced efficiency than due to absenteeism.

No abstract

The travelling salesman problem (TSP) belongs to the class of NP-hard problems, in which an optimal solution to the problem cannot be obtained within a reasonable computational time for large-sized problems. To address TSP, we propose a hybrid algorithm, called GA-TCTIA-LBSA, in which a genetic algorithm (GA), tour construction and tour improvement algorithms (TCTIAs) and a list-based simulated annealing (LBSA) algorithm are used. The TCTIAs are introduced to generate a first population, and after that, a search is continued with the GA. The problem of premature convergence of the GA to local optimum is tackled by a method called social disaster technique. Afterwards, the LBSA is applied to generate a new population based on one of two proposed operators called packing and judgement day. The proposed algorithm is implemented in the MATLAB environment, and its two variants, called GA-TCTIA-LBSA packing and GA-TCTIA-LBSA judgement day, are tested on symmetric and asymmetric instances from TSPLIB. The overall results demonstrate that the proposed GA-TCTIA-LBSAs offer promising results, particularly for small-sized instances.

The aloin‐like substance formerly referred to as Compound A1, has been resolved into four closely allied anthraquinone derivatives by paper chromatographic and countercurrent techniques. Two of these substances have been isolated in pure form and their general properties, melting point, optical rotation, RF values and ultra‐violet light absorption curves are recorded. Treatment with ferric chloride yields aloe‐emodin from both, and each on mild hydrolysis, produces barbaloin. The names Cascaroside A and Cascaroside B are proposed. Preliminary work on the other two components has shown that they are based on a compound similar to barbaloin but a derivative of chrysophanol instead of aloe‐emodin; the name chrysaloin is suggested for this substance.