Neuroanatomy of the Subadult and Fetal Brain of the Atlantic White-Sided Dolphin (Lagenorhynchus acutus) from In Situ Magnetic Resonance Images

This article provides the first anatomically labeled, magnetic resonance imaging (MRI) -based atlas of the subadult and fetal Atlantic white-sided dolphin (Lagenorhynchus acutus) brain. It differs from previous MRI-based atlases of cetaceans in that it was created from images of fresh, postmortem brains in situ rather than extracted, formalin-fixed brains. The in situ images displayed the classic hallmarks of odontocete brains: fore-shortened orbital lobes and pronounced temporal width. Olfactory structures were absent and auditory regions (e.g., temporal lobes and inferior colliculi) were enlarged. In the subadult and fetal postmortem MRI scans, the hippocampus was identifiable, despite the relatively small size of this structure in cetaceans. The white matter tracts of the fetal hindbrain and cerebellum were pronounced, but in the telencephalon, the white matter tracts were much less distinct, consistent with less myelin. The white matter tracts of the auditory pathways in the fetal brains were myelinated, as shown by the T2 hypointensity signals for the inferior colliculus, cochlear nuclei, and trapezoid bodies. This finding is consistent with hearing and auditory processing regions maturing in utero in L. acutus, as has been observed for most mammals. In situ MRI scanning of fresh, postmortem specimens can be used not only to study the evolution and developmental patterns of cetacean brains but also to investigate the impacts of natural toxins (such as domoic acid), anthropogenic chemicals (such as polychlorinated biphenyls, polybrominated diphenyl ethers, and their hydroxylated metabolites), biological agents (parasites), and noise on the central nervous system of marine mammal species

Stress Resistance and Longevity Are Not Directly Linked to Levels of Enzymatic Antioxidants in the Ponerine Ant Harpegnathos saltator

BACKGROUND: The molecular mechanisms of variations in individual longevity are not well understood, even though longevity can be increased substantially by means of diverse experimental manipulations. One of the factors supposed to be involved in the increase of longevity is a higher stress resistance. To test this hypothesis in a natural system, eusocial insects such as bees or ants are ideally suited. In contrast to most other eusocial insects, ponerine ants show a peculiar life history that comprises the possibility to switch during adult life from a normal worker to a reproductive gamergate, therewith increasing their life expectancy significantly. RESULTS: We show that increased resistance against major stressors, such as reactive oxygen species and infection accompanies the switch from a life-history trait with normal lifespan to one with a longer life expectancy. A short period of social isolation was sufficient to enhance stress resistance of workers from the ponerine ant species Harpegnathos saltator significantly. All ant groups with increased stress resistances (reproducing gamergates and socially isolated workers) have lower catalase activities and glutathione levels than normal workers. Therewith, these ants resemble the characteristics of the youngest ants in the colony. CONCLUSIONS: Social insects with their specific life history including a switch from normal workers to reproducing gamergates during adult life are well suited for ageing research. The regulation of stress resistance in gamergates seemed to be modified compared to foraging workers in an economic way. Interestingly, a switch towards more stress resistant animals can also be induced by a brief period of social isolation, which may already be associated with a shift to a reproductive trajectory. In Harpegnathos saltator, stress resistances are differently and potentially more economically regulated in reproductive individuals, highlighting the significance of reproduction for an increase in longevity in social insects. As already shown for other organisms with a long lifespan, this trait is not directly coupled to higher levels of enzymatic and non-enzymatic antioxidants

How a Diverse Research Ecosystem Has Generated New Rehabilitation Technologies: Review of NIDILRR’s Rehabilitation Engineering Research Centers

Over 50 million United States citizens (1 in 6 people in the US) have a developmental, acquired, or degenerative disability. The average US citizen can expect to live 20% of his or her life with a disability. Rehabilitation technologies play a major role in improving the quality of life for people with a disability, yet widespread and highly challenging needs remain. Within the US, a major effort aimed at the creation and evaluation of rehabilitation technology has been the Rehabilitation Engineering Research Centers (RERCs) sponsored by the National Institute on Disability, Independent Living, and Rehabilitation Research. As envisioned at their conception by a panel of the National Academy of Science in 1970, these centers were intended to take a “total approach to rehabilitation”, combining medicine, engineering, and related science, to improve the quality of life of individuals with a disability. Here, we review the scope, achievements, and ongoing projects of an unbiased sample of 19 currently active or recently terminated RERCs. Specifically, for each center, we briefly explain the needs it targets, summarize key historical advances, identify emerging innovations, and consider future directions. Our assessment from this review is that the RERC program indeed involves a multidisciplinary approach, with 36 professional fields involved, although 70% of research and development staff are in engineering fields, 23% in clinical fields, and only 7% in basic science fields; significantly, 11% of the professional staff have a disability related to their research. We observe that the RERC program has substantially diversified the scope of its work since the 1970’s, addressing more types of disabilities using more technologies, and, in particular, often now focusing on information technologies. RERC work also now often views users as integrated into an interdependent society through technologies that both people with and without disabilities co-use (such as the internet, wireless communication, and architecture). In addition, RERC research has evolved to view users as able at improving outcomes through learning, exercise, and plasticity (rather than being static), which can be optimally timed. We provide examples of rehabilitation technology innovation produced by the RERCs that illustrate this increasingly diversifying scope and evolving perspective. We conclude by discussing growth opportunities and possible future directions of the RERC program

The unexpected resurgence of Weyl geometry in late 20-th century physics

Weyl's original scale geometry of 1918 ("purely infinitesimal geometry") was withdrawn by its author from physical theorizing in the early 1920s. It had a comeback in the last third of the 20th century in different contexts: scalar tensor theories of gravity, foundations of gravity, foundations of quantum mechanics, elementary particle physics, and cosmology. It seems that Weyl geometry continues to offer an open research potential for the foundations of physics even after the turn to the new millennium.Comment: Completely rewritten conference paper 'Beyond Einstein', Mainz Sep 2008. Preprint ELHC (Epistemology of the LHC) 2017-02, 92 pages, 1 figur

improving mockup based requirement specification with end user annotations

Agile approaches, one of the key methodologies used in today's software projects, often rely on user interface mockups for capturing the goals that the system must satisfy. Mockups, as any other requirement artifact, may suffer from ambiguity and contradiction issues when several points of view are surveyed/elicited by different analysts. This article introduces a novel approach that enhances mockups with friendly end-user annotations that helps formalizing the requirements and reducing or identifying conflicts. We present an evaluation of the approach in order to measure how the use of annotations improves requirements quality

Geographical Distribution and Genetic Diversity of Bank Vole Hepaciviruses in Europe

The development of new diagnostic methods resulted in the discovery of novel hepaciviruses in wild populations of the bank vole (Myodes glareolus, syn. Clethrionomys glareolus). The naturally infected voles demonstrate signs of hepatitis similar to those induced by hepatitis C virus (HCV) in humans. The aim of the present research was to investigate the geographical distribution of bank vole-associated hepaciviruses (BvHVs) and their genetic diversity in Europe. Real-time reverse transcription polymerase chain reaction (RT-qPCR) screening revealed BvHV RNA in 442 out of 1838 (24.0%) bank voles from nine European countries and in one of seven northern red-backed voles (Myodes rutilus, syn. Clethrionomys rutilus). BvHV RNA was not found in any other small mammal species (n = 23) tested here. Phylogenetic and isolation-by-distance analyses confirmed the occurrence of both BvHV species (Hepacivirus F and Hepacivirus J) and their sympatric occurrence at several trapping sites in two countries. The broad geographical distribution of BvHVs across Europe was associated with their presence in bank voles of different evolutionary lineages. The extensive geographical distribution and high levels of genetic diversity of BvHVs, as well as the high population fluctuations of bank voles and occasional commensalism in some parts of Europe warrant future studies on the zoonotic potential of BvHVs.Peer reviewe