Authorship Trends Over the Past 30-Years in the Annals of Biomedical Engineering

In academia, manuscripts serve as an important component of career development. The past several years have seen heightened evaluation of the role of the gender gap in career advancement, as well as other bibliometric changes in publications. We therefore analyzed authorship and publication trends in the Annals of Biomedical Engineering over the past three decades (one complete year of manuscripts for each decade; 1986, 1996, 2006, and 2016). The variables analyzed were number of authors per manuscript, numerical position of the corresponding author, number of collaborating institutions and countries, number of references, and number of citations per manuscript. The gender of both the first and corresponding authors was identified and analyzed over time and by region. Globally, the percentage of female first and corresponding authors significantly increased from 0% in 1986 to 28.6% (p = 0.003) and 20.4% (p = 0.0009), respectively, in 2016. Although there were significant differences regarding female first and corresponding author over time, they did not vary by region of origin (p = 0.5 and 0.2, respectively). Overall, these findings highlight the improvements made and the challenges that still exist related to publishing within the bioengineering field

Skeletal adaptations in young male mice after 4 weeks aboard the International Space Station

Gravity has an important role in both the development and maintenance of bone mass. This is most evident in the rapid and intense bone loss observed in both humans and animals exposed to extended periods of microgravity in spaceflight. Here, cohabitating 9-week-old male C57BL/6 mice resided in spaceflight for ~4 weeks. A skeletal survey of these mice was compared to both habitat matched ground controls to determine the effects of microgravity and baseline samples in order to determine the effects of skeletal maturation on the resulting phenotype. We hypothesized that weight-bearing bones would experience an accelerated loss of bone mass compared to non-weight-bearing bones, and that spaceflight would also inhibit skeletal maturation in male mice. As expected, spaceflight had major negative effects on trabecular bone mass of the following weight-bearing bones: femur, tibia, and vertebrae. Interestingly, as opposed to the bone loss traditionally characterized for most weight-bearing skeletal compartments, the effects of spaceflight on the ribs and sternum resembled a failure to accumulate bone mass. Our study further adds to the insight that gravity has site-specific influences on the skeleton

Transparent exopolymer particles (TEP) in aquatic environments.

Since the development of methods to quantify transparent exopolymer particles (TEP) 1993, it has been shown that these gel-particles are not only ubiquitous and abundant, but also play a significant role in the biogeochemical cycling of elements and the structuring of food webs. TEP may be quantified either microscopically or colorimetrically. Although data based on measurements using one or other of these methods are not directly comparable, the results are consistent. TEP abundances in fresh and marine waters are in the same range as those of phytoplankton, with peak values occurring during phytoplankton blooms. TEP are very sticky particles that exhibit the characteristics of gels, and consist predominantly of acidic polysaccharides. In marine systems the majority of TEP are formed abiotically from dissolved precursors, which are released by phytoplankton that are either actively growing or are senescent. TEP are also generated during the sloughing of cell surface mucus and the disintegration of colonial matrices. The impact of exopolymers in the creation of microhabitats and in the cycling of trace compounds varies with the state in which the polymers occur, either as particles or as solute slimes. As particles, TEP provide surfaces for the colonization by bacteria and transfer by adsorption, trace solute substances into the particulate pool. As dissolved polymers they are mixed with the water and can neither be filtered nor aggregated. Because of their high abundances, large size and high stickiness, TEP enhance or even facilitate the aggregation of solid, non-sticky particles. They have been found to form the matrices of all marine aggregates investigated to date. By aggregating solid particles, TEP promote the sedimentation of particles, and, because their carbon content is high, their direct contribution to fluxes of carbon into deep water is significant. The direct sedimentation of TEP may represent a mechanism for the selective sequestration of carbon in deep water, because the C:N ratios of TEP lie well above the Redfield ratio. The turnover time of TEP as a result of bacterial degradation appears to range from hours to months, depending on the chemical composition and age of TEP. TEP may also be utilized not only by filter feeders (some protozoans and appendicularian) but TEP-rich microaggregates, consisting of pico- and nano-plankton are also readily grazed by euphausiids, thus permitting the uptake of particles that would otherwise be too small to be grazed directly by euphausiids. This short-circuits food chains and links the microbial food-web to the classical food-web. It is suggested that this expansion of the concept of food webs, linking the microbial loop with an aggregation web will provide a more complete description of particle dynamics. (C) 2002 Elsevier Science Ltd. All rights reserved