Explicitly searching for useful inventions: dynamic relatedness and the costs of connecting versus synthesizing

Inventions combine technological features. When features are barely related, burdensomely broad knowledge is required to identify the situations that they share. When features are overly related, burdensomely broad knowledge is required to identify the situations that distinguish them. Thus, according to my first hypothesis, when features are moderately related, the costs of connecting and costs of synthesizing are cumulatively minimized, and the most useful inventions emerge. I also hypothesize that continued experimentation with a specific set of features is likely to lead to the discovery of decreasingly useful inventions; the earlier-identified connections reflect the more common consumer situations. Covering data from all industries, the empirical analysis provides broad support for the first hypothesis. Regressions to test the second hypothesis are inconclusive when examining industry types individually. Yet, this study represents an exploratory investigation, and future research should test refined hypotheses with more sophisticated data, such as that found in literature-based discovery research

Extra-articular fractures of the proximal phalanges of the fingers: a comparison of 2 methods of functional, conservative treatment

PURPOSE: For nonsurgical treatment of fractures of the proximal phalanges of the triphalangeal fingers, different dynamic casts have been described. The main principle behind these casts is advancement and tightening of the extensor hood, caused by a combination of blocking the metacarpophalangeal joints in flexion and actively flexing the proximal interphalangeal joints. In contrast to established treatment protocols using functional forearm casts, the Lucerne cast allows for free mobilization of the wrist joint. The purpose of the current multicenter study was to compare the results of conservative, functional treatment using 2 different methods, either a forearm cast or a Lucerne cast. METHODS: Over a 2-year-period, a prospective, randomized, multicenter study was conducted at 4 hospitals in Switzerland. Clinical and radiological results of 66 consecutive patients having 75 extra-articular fractures of the proximal phalanges were recorded through a minimum follow-up of 3 months. Intra-articular and physeal fractures, pathological fractures, open fractures, concomitant injuries of the tendons or collateral ligaments, and accidents more than 7 days before presentation were excluded from the study. RESULTS: Radiographically, there were no statistically significant differences between the 2 groups in terms of palmar apex angulation and radial or ulnar angulation. There were no differences in total active range of finger motion. Wrist joint motion at the time of cast removal was statistically superior in patients treated with Lucerne cast. However, there were no significant differences in wrist joint motion at 12 weeks of follow-up. CONCLUSIONS: The clinical and radiological results achieved with the Lucerne cast are comparable to those of established treatment. Well-reduced, minimally angulated, or nonangulated fractures of the proximal phalanges of the fingers can be effectively treated using functional casts without immobilizing the wrist. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic II

Towards a molecular epidemiology of alcohol dependence analysing the interplay of genetic and environmental risk factors

Background Progress in identifying genetic factors protective against alcohol dependence (AlcD) requires a paradigm shift in psychiatric epidemiology. Aims To integrate analysis of research into the genetics of alcoholism. Method Data from prospective questionnaire and interview surveys of the Australian twin panel, and from a subsample who underwent alcohol challenge, were analysed. Results In men, effects of alcohol dehydrogenase ADH2*1/*2 genotype or high alcohol sensitivity (risk-decreasing), and of history of childhood conduct disorder, or having monozygotic co-twin or twin sister with AlcD (risk-increasing) were significant and comparable in magnitude. Religious affiliation (Anglican versus other) was associated with the ADH2 genotype, but did not explain the associations with AlcD symptoms. No protective effect of the ADH2*1/*2 genotype was observed in women. Conclusions The early onset and strong familial aggregation of AlcD, and opportunity for within-family tests of genetic association to avoid confounding effects, make epidemiological family studies of adolescents and young adults and their families a priority