Physical,Human and Divine attraction in the life and thought of George Cheyne

This paper is a study of the mental environment of the Newtonian conception of attraction in the case of George Cheyne, M.D. (1671–1743), physician of the early 18th century and author of a number of popular medical works. It traces the growth of his notions of a spiritual attraction between God and his creatures and between the creatures themselves, and the relation of these ideas both to his use of the Newtonian model of short-range attraction, and to his conception of the creatures as reflections of the divine essence. The paper contends that the development of these aspects of Cheyne's thought harmonizes with the changing pattern of his life, and that this harmony is expressed by his general technique of reasoning by analogy between the various spheres of experience.     

Vaspin inhibits kallikrein 7 by serpin mechanism

The molecular target of the adipokine vaspin (visceral adipose tissue-derived serpin; serpinA12) and its mode of action are unknown. Here, we provide the vaspin crystal structure and identify human kallikrein 7 (hK7) as a first protease target of vaspin inhibited by classical serpin mechanism with high specificity in vitro. We detect vaspin–hK7 complexes in human plasma and find co-expression of both proteins in murine pancreatic β-cells. We further demonstrate that hK7 cleaves human insulin in the A- and B-chain. Vaspin treatment of isolated pancreatic islets leads to increased insulin concentration in the media upon glucose stimulation without influencing insulin secretion. By application of vaspin and generated inactive mutants, we find the significantly improved glucose tolerance in C57BL/6NTac and db/db mice treated with recombinant vaspin fully dependent on the vaspin serpin activity and not related to vaspin-mediated changes in insulin sensitivity as determined by euglycemic-hyperinsulinemic clamp studies. Improved glucose metabolism could be mediated by increased insulin plasma concentrations 150 min after a glucose challenge in db/db mice, supporting the hypothesis that vaspin may inhibit insulin degradation by hK7 in the circulation. In conclusion, we demonstrate the inhibitory serpin nature and the first protease target of the adipose tissue-derived serpin vaspin, and our findings suggest hK7 inhibition by vaspin as an underlying physiological mechanism for its compensatory actions on obesity-induced insulin resistance.     

Enhancing momentum investment strategy using leverage

Previous studies examine investment strategies based on leverage and momentum; none investigates both variables jointly as an investment strategy. This paper is the first incorporating leverage and momentum together. We show that low past returns (losers) forecast future negative abnormal returns only among stocks with high leverage levels, but not among stocks with low leverage levels. However, high past returns (winners) forecast future positive abnormal returns independently of leverage level. As a result, the negative relation between leverage and future abnormal returns is only observed among loser stocks, and the positive relation between past returns and future abnormal returns is only shown among non‐low leverage stocks. Our results are important in achieving better investment strategies: buying winners' stocks (independently of their level of leverage) and short‐selling losers' stocks with high leverage yield higher abnormal returns than strategies based on only one of these variables. Our two‐dimensional strategy yields risk‐adjusted abnormal returns of 15.66% per annum, whereas the single leverage or momentum strategies yield 7.70% and 7.96% per annum, respectively. The difference is nearly 8% and economically significant. If leverage is considered as proxy for default risk, our results, contrary to previous evidence, show that momentum profits are not exclusive of default stocks, and that momentum returns are not only driven by negative returns yielded by distress stocks.     

The occurrence and function of the sphragis in the zerynthiine genera Zerynthia,Allancastria and Bhutanitis (Lepidoptera: Papilionoidea: Papilionidae)

In some butterfly species males attach a large external mating plug termed a sphragis to the female abdomen during mating. This is derived from male accessory secretions and covers the female ostium bursae and surrounding areas, thus preventing or delaying remating. Specimens of all 12 species of the genera Zerynthia, Allancastria and Bhutanitis (Lepidoptera: papilionidae), which form a natural clade within the Zerynthiini, were examined for presence or absence of a sphragis and their male and female genitalia were studied. In all three genera female genitalia lack a typical sinus vaginalis and the sterigma is modified to form an exposed, shiny, well-sclerotized genital plate, derived from the fusion and expansion of the lamellae ante- and postvaginales. The exposed ostium bursae is situated near the posterior end of the genital plate in Zerynthia, whereas in Allancastria and Bhutanitis it is near the anterior end. A crude irregularly formed sphragis was found at least facultatively in all species. The sphragides of Zerynthia and Bhutanitis were generally poorly developed, in most cases only partially covering the female genital plate. In Allancastria the sphragis mostly covered the genital plate entirely, and generally incorporated numerous long scales derived from the male’s 8th abdominal segment; scales were sometimes sparse or absent, probably due to depletion from repeated matings by males. In Zerynthia, males lacked the dense terminal abdominal tuft of elongated scales found in Allancastria, and their sphragis lacked scales. The sphragis of Bhutanitis thaidina incorporated scales from the male valves, whereas in the B. lidderdalii sphragis (and probably B. ludlowi) the scales derived from the male’s 8th abdominal segment. The role of the scales and possible reasons for the difference in the development of the sphragis among these genera are discussed.     

Parasite community of the golden cownose ray Rhinoptera steindachneri Evermann and Jenkins 1891 (Chondrichthyes: Myliobatidae), in Acapulco Bay,Guerrero, Mexico

The parasite community of the ray Rhinoptera steindachneri from Acapulco Bay was examined and quantified; analyses were based on the sex of the host and the date of sampling. A total of 171 specimens of R. steindachneri were examined during July–August of 2010, and May and July of 2012. Twenty-one species of parasites were found: three species of Monogenea; eight adult and one larval species of Cestoda; one larval species of Nematoda; five species of Copepoda; two species of Isopoda; and one species of Hirudinea. Cestodes had the greatest species richness (43% of the total species), followed by the copepods (24%). Two species of cestode, Glyphobothrium sp. and Rhinebothrium sp., were collected only from adult rays. At the component community level, species richness showed statistically significant variation between 13 and 16 species, which is similar to previous reports for other species of rays. The parasite component communities and infracommunities of R. steindachneri exhibited similar patterns: high species number and low numerical dominance by a particular species of parasite. The differences of body size of male vs. female rays, and a change in diet and feeding behaviour with the age of R. steindachneri, are likely important factors in the structuring of their parasite communities.