Evolution of linkages for prototyping of linkage based robots

Prototyping robotic systems is a time consuming process. Computer aided design, however, might speed up the process significantly. Quality-diversity evolutionary approaches optimise for novelty as well as performance, and can be used to generate a repertoire of diverse designs. This design repertoire could be used as a tool to guide a designer and kick-start the rapid prototyping process. This paper explores this idea in the context of mechanical linkage based robots. These robots can be a good test-bed for rapid prototyping, as they can be modified quickly for swift iterations in design. We compare three evolutionary algorithms for optimising 2D mechanical linkages: 1) a standard evolutionary algorithm, 2) the multi-objective algorithm NSGA-II, and 3) the quality-diversity algorithm MAP-Elites. Some of the found linkages are then realized on a physical hexapod robot through a prototyping process, and tested on two different floors. We find that all the tested approaches, except the standard evolutionary algorithm, are capable of finding mechanical linkages that creates a path similar to a specified desired path. However, the quality-diversity approaches that had the length of the linkage as a behaviour descriptor were the most useful when prototyping. This was due to the quality-diversity approaches having a larger variety of similar designs to choose from, and because the search could be constrained by the behaviour descriptors to make linkages that were viable for construction on our hexapod platform

Human miR-1271 is a miR-96 paralog with distinct non-conserved brain expression pattern

Recent deep-sequencing efforts have identified many novel non-conserved small RNAs that are expressed at low levels in certain mammalian cells. Whether these small RNAs are important for mammalian physiology is debatable, therefore we explored the function of one such RNA, human miR-1271. This small RNA is similar in sequence to miR-96, a highly conserved microRNA that when mutated causes hearing loss in humans and mice. Although the miR-1271 and miR-96 sequences differ slightly, our in vitro assays indicate that they have an identical regulatory activity. We have identified brain-expressed mRNAs from genes including, GPHN, RGS2, HOMER1 and KCC2, which share the same miR-96 and miR-1271 regulatory elements. Interestingly, human miR-1271 is expressed abundantly in brain tissue, where miR-96 is not highly expressed. The rodent miR-1271 precursor contains several sequence differences in the precursor stem, which appear to reduce the efficiency of microRNA processing. Our data indicate that although miR-1271 and miR-96 function identically in vitro, they function to some extent uniquely in vivo. Given the expression patterns and nature of the target genes, miR-1271 may have a significant, although non-conserved, role in regulating aspects of neural development or function in humans

Dwelling as the life basis of Ukrainians

На прикладі містечок Батурина, Глухова, Борзни та Кролевця у статті розглядається інтер’єр жител населення Чернігово-Сіверщини (друга половина ХVІІІ – середина ХІХ ст.). На основі значного описового матеріалу, стосовно звичаїв і побуту українців, який накопичився в середині і особливо в другій половині ХІХ ст. можна зробити науково-вивірені узагальнення з приводу порівняльної характеристики українців і росіян. Дослідженням цієї теми займалися М. Маркевич, І. Срезнєвський, П. Куліш та ін. Значний внесок до вивчення даної проблематики належить історику М. Костомарову, який виокремив український культурний і традиційно-буттєвий комплекс із загальноросійського, що утрадиційнилось як спільне за понад сторіччя співжиття в рамках однієї імперії. Також у даній статті характеризується поділ оселі на умовні частини та визначаються основні сакральні центри хати. Автор наголошує на глибокому символічному обрядово-ритуальному значенні, яке українці надавали всім предметам хатнього інтер’єру та наголошує на ліричній прив’язаності їх до місця свого проживання.На примере городков Батурина, Глухова, Борзны и Кролевца в статье рассматривается интерьер жилищ населения Чернигово-Северщины во второй половине XVIII – середине XIX вв. На основе материалов, описывающих украинские обычаи и быт, накопившихся в средине, а особенно во второй половине XIX в., можно сделать обобщения по поводу сравнительной характеристики украинцев и русских. Исследованием этой темы занимались Н. Маркевич, И. Срезневский, П. Кулиш и другие ученые. Значительный вклад в изучение данной проблематики принадлежит историку Н. Костомарову, который выделил украинский культурный и традиционно- бытейный комплекс из общероссийского, которые сосуществовали более столетия в границах одной империи. Также в данной статье характеризируется разделение жилища на условные части и определяются основные сакральные центры дома (хаты). Автор отмечает глубокое символическое ритуально-обрядовое значение, которое украинцы придавали всем предметам домашнего интерьера, а также подчеркивает лирическую привязанность населения к месту его проживания.Article deals with the interior of dwellings in Chernihiv-Siverskyi region (in the 2nd half of the ХVІІІ – 1st half of the ХІХ cent.). On the example of towns Baturyn, Glukhiv, Borzna and Krolevets the article deals with the house interiors of the population of Chernihovo-Sivershchyna (the second half of the XVIII – mid. XIX cent.). The analysis is based on considerable descriptive material concerning Ukrainian customs and way of life that has accumulated in the middle and especially in the second half of the XIX cent. and led to scientific adjusted conclusion about the comparative characteristics of Ukrainians and Russians. This topic was researched by M. Markevych, I. Sreznevskyi, P. Kulish and others. A significant contribution to the study of this subject belongs to historian M. Kostomarov, who singled Ukrainian cultural and traditional existential complex out of all-Russian complex, that was considered unified for more than three centuries of coexistence within a single empire. Also, this article characterizes the division of the house on special parts and identifies the main sacred centres of the house. The attention is given to the fact that the Ukrainian housing is associated with many beliefs and rituals. It indicates that the dwelling-house reflects not only people’s ideological and artistic heritage, but also a pragmatic idea. After all, the house seemed a model of nature and the universe, which protected both physically and spiritually. We know that house was not only a place where the family spent most of its life, but it was the family hearth around which ancient and beautiful traditions were preserved. The author emphasizes the deep symbolic ritual value that Ukrainians gave to all subjects of domestic interior and the lyrical attachment to their place of residence. After all, the house had a kind of sacred meaning for its tenants, that is why, to the house and all domestic things people gave some philosophical content. Complexity of representations of the world for humans began from the dwelling and was a dominant through all life. It is revealed that a Ukrainian house with its aesthetic appearance and its interior in particular, is an important factor in the understanding of the Ukrainian people and makes the character unique, and one that is very different from the characteristics of other nations. The author concluded that this topic needs a further study

The genomes of two key bumblebee species with primitive eusocial organization

Background: The shift from solitary to social behavior is one of the major evolutionary transitions. Primitively eusocial bumblebees are uniquely placed to illuminate the evolution of highly eusocial insect societies. Bumblebees are also invaluable natural and agricultural pollinators, and there is widespread concern over recent population declines in some species. High-quality genomic data will inform key aspects of bumblebee biology, including susceptibility to implicated population viability threats. Results: We report the high quality draft genome sequences of Bombus terrestris and Bombus impatiens, two ecologically dominant bumblebees and widely utilized study species. Comparing these new genomes to those of the highly eusocial honeybee Apis mellifera and other Hymenoptera, we identify deeply conserved similarities, as well as novelties key to the biology of these organisms. Some honeybee genome features thought to underpin advanced eusociality are also present in bumblebees, indicating an earlier evolution in the bee lineage. Xenobiotic detoxification and immune genes are similarly depauperate in bumblebees and honeybees, and multiple categories of genes linked to social organization, including development and behavior, show high conservation. Key differences identified include a bias in bumblebee chemoreception towards gustation from olfaction, and striking differences in microRNAs, potentially responsible for gene regulation underlying social and other traits. Conclusions: These two bumblebee genomes provide a foundation for post-genomic research on these key pollinators and insect societies. Overall, gene repertoires suggest that the route to advanced eusociality in bees was mediated by many small changes in many genes and processes, and not by notable expansion or depauperation

Importance of the Global Regulators Agr and SaeRS in the Pathogenesis of CA-MRSA USA300 Infection

CA-MRSA infection, driven by the emergence of the USA300 genetic background, has become epidemic in the United States. USA300 isolates are hypervirulent, compared with other CA- and HA-MRSA strains, in experimental models of necrotizing pneumonia and skin infection. Interestingly, USA300 isolates also have increased expression of core genomic global regulatory and virulence factor genes, including agr and saeRS. To test the hypothesis that agr and saeRS promote the observed hypervirulent phenotype of USA300, isogenic deletion mutants of each were constructed in USA300. The effects of gene deletion on expression and protein abundance of selected downstream virulence genes were assessed by semiquantitative real-time reverse-transcriptase PCR (qRT-PCR) and western blot, respectively. The effects of gene deletion were also assessed in mouse models of necrotizing pneumonia and skin infection. Deletion of saeRS, and, to a lesser extent, agr, resulted in attenuated expression of the genes encoding α-hemolysin (hla) and the Panton-Valentine leukocidin (lukSF-PV). Despite the differences in hla transcription, the toxin was undetectable in culture supernatants of either of the deletion mutants. Deletion of agr, but not saeRS, markedly increased the expression of the gene encoding protein A (spa), which correlated with increased protein abundance. Each deletion mutant demonstrated significant attenuation of virulence, compared with wild-type USA300, in mouse models of necrotizing pneumonia and skin infection. We conclude that agr and saeRS each independently contribute to the remarkable virulence of USA300, likely by means of their effects on expression of secreted toxins

The critical role of the linear plasmid lp36 in the infectious cycle of Borrelia burgdorferi

Borrelia burgdorferi, the aetiological agent of Lyme disease, follows a life cycle that involves passage between the tick vector and the mammalian host. To investigate the role of the 36 kb linear plasmid, lp36 (also designated the B. burgdorferi K plasmid), in the infectious cycle of B. burgdorferi, we examined a clone lacking this plasmid, but containing all other plasmids known to be required for infectivity. Our results indicated that lp36 was not required for spirochete survival in the tick, but the clone lacking lp36 demonstrated low infectivity in the mammal. Restoration of lp36 to the mutant strain confirmed that the infectivity defect was due to loss of lp36. Moreover, spirochetes lacking lp36 exhibited a nearly 4-log increase in ID50 relative to the isogenic lp36+ clone. The infectivity defect of lp36-minus spirochetes was localized, in part, to loss of the bbk17 (adeC) gene, which encodes an adenine deaminase. This work establishes a vital role for lp36 in the infectious cycle of B. burgdorferi and identifies the bbk17 gene as a component of this plasmid that contributes to mammalian infectivity

Genetic Cross-Interaction between APOE and PRNP in Sporadic Alzheimer's and Creutzfeldt-Jakob Diseases

Alzheimer's disease (AD) and Creutzfeldt-Jakob disease (CJD) represent two distinct clinical entities belonging to a wider group, generically named as conformational disorders that share common pathophysiologic mechanisms. It is well-established that the APOE ε4 allele and homozygosity at polymorphic codon 129 in the PRNP gene are the major genetic risk factors for AD and human prion diseases, respectively. However, the roles of PRNP in AD, and APOE in CJD are controversial. In this work, we investigated for the first time, APOE and PRNP genotypes simultaneously in 474 AD and 175 sporadic CJD (sCJD) patients compared to a common control population of 335 subjects. Differences in genotype distribution between patients and control subjects were studied by logistic regression analysis using age and gender as covariates. The effect size of risk association and synergy factors were calculated using the logistic odds ratio estimates. Our data confirmed that the presence of APOE ε4 allele is associated with a higher risk of developing AD, while homozygosity at PRNP gene constitutes a risk for sCJD. Opposite, we found no association for PRNP with AD, nor for APOE with sCJD. Interestingly, when AD and sCJD patients were stratified according to their respective main risk genes (APOE for AD, and PRNP for sCJD), we found statistically significant associations for the other gene in those strata at higher previous risk. Synergy factor analysis showed a synergistic age-dependent interaction between APOE and PRNP in both AD (SF = 3.59, p = 0.027), and sCJD (SF = 7.26, p = 0.005). We propose that this statistical epistasis can partially explain divergent data from different association studies. Moreover, these results suggest that the genetic interaction between APOE and PRNP may have a biological correlate that is indicative of shared neurodegenerative pathways involved in AD and sCJD