Division of labour and worker size polymorphism in ant colonies: the impact of social and genetic factors

Division of labour among workers is central to the organisation and ecological success of insect societies. If there is a genetic component to worker size, morphology or task preference, an increase in colony genetic diversity arising from the presence of multiple breeders per colony might improve division of labour. We studied the genetic basis of worker size and task preference in Formica selysi, an ant species that shows natural variation in the number of mates per queen and the number of queens per colony. Worker size had a heritable component in colonies headed by a doubly mated queen (h 2=0.26) and differed significantly among matrilines in multiple-queen colonies. However, higher levels of genetic diversity did not result in more polymorphic workers across single- or multiple-queen colonies. In addition, workers from multiple-queen colonies were consistently smaller and less polymorphic than workers from single-queen colonies. The relationship between task, body size and genetic lineage appeared to be complex. Foragers were significantly larger than brood-tenders, which may provide energetic or ergonomic advantages to the colony. Task specialisation was also often associated with genetic lineage. However, genetic lineage and body size were often correlated with task independently of each other, suggesting that the allocation of workers to tasks is modulated by multiple factors. Overall, these results indicate that an increase in colony genetic diversity does not increase worker size polymorphism but might improve colony homeostasi

Система обработки данных по оптическим и микрофизическим характеристикам аэродисперсной среды для оценки ослабления лучистой энергии

Разработана информационно-вычислительная система, реализующая численный эксперимент по определению ослабления и пропускания оптического излучения аэродисперсной средой. В качестве моделей отдельных рассеивателей рассмотрены столбики, пластинки, сферы, а также их агрегатов. В систему включаются архивы баз данных Aeronet и Hitran оптических и микрофизических характеристик кристаллических облаков. Программный комплекс ориентирован на обработку данных по ослаблению видимого и ИК излучения. Сравнительный анализ данных численного и натурного экспериментов показал возможность оценки физико-химических параметров среды

Woman – victim, culprit and witness in three medieval legal texts

The paper analyzes three medieval Slavic legal documents, two of which were written in Cyrillic and one in Glagolitic. The oldest Slavic medieval legal text was written in Cyrillic. It is known as the Russian Justice, its oldest parts date back to the 11th century, but the text underwent numerous revisions up until the 17th century. The Poljica Statute is also in Cyrillic, and despite being dated to the year 1440, the document contains considerably older records. The third document is the Vinodol Code, the only explicitly dated text of the three to January 6, 1288, but whose transcript dates from the 16th century. This is the oldest Croatian legal text, while the said Russian Justice is the oldest Slavic legal text. The analysis focuses on the position of women within these three legal documents. Additionally, the first Croatian translation of the Russian Justice is contained in this article

Woman – victim, culprit and witness in three medieval legal texts

The paper analyzes three medieval Slavic legal documents, two of which were written in Cyrillic and one in Glagolitic. The oldest Slavic medieval legal text was written in Cyrillic. It is known as the Russian Justice, its oldest parts date back to the 11th century, but the text underwent numerous revisions up until the 17th century. The Poljica Statute is also in Cyrillic, and despite being dated to the year 1440, the document contains considerably older records. The third document is the Vinodol Code, the only explicitly dated text of the three to January 6, 1288, but whose transcript dates from the 16th century. This is the oldest Croatian legal text, while the said Russian Justice is the oldest Slavic legal text. The analysis focuses on the position of women within these three legal documents. Additionally, the first Croatian translation of the Russian Justice is contained in this article

Pathophysiological Factors in the Relationship between Chronological Age and Calculated Lung Age as Detected in a Screening Setting in Community-Dwelling Subjects

Aim: To explore the relationship between pathophysiological factors and premature lung ageing in a cohort of community-dwelling subjects in a health-screening setting. Methods: 16,107 pharmacy customers in Germany (5954 males, 10153 females; mean age 59.7 years)) participated in a lung function screening project by providing demographic data including smoking status and known airway conditions and performing spirometry with a Vitalograph, a spirometry screening device. Lung age was calculated from the spirometric findings, and the difference between chronological age and calculated lung age was analyzed in its relationship to the demographic data in general linear models. Results: In the overall cohort, calculated lung age exceeded chronological age by 10.0 years. Based on the subset of non-smokers not reporting any airway conditions, Vitalograph data in this setting may underestimate FEV1 to some degree but this apparently had little impact on the detection of association of lung age with pathophysiological factors or the corresponding effect sizes. The most important factors associated with greater lung age based on strength of association were presence of dyspnea, being a smoker and reporting a history of COPD or asthma. Corresponding effect sizes for the difference between age and lung age were 6.5, 5.7, 13.9 and 8.3 years over the chronological age. Discussion and Conclusions: These data confirm the usefulness of screening devices of lung function testing for epidemiological but potentially also for pharmaco-epidemiological studies

An advanced glioma cell invasion assay based on organotypic brain slice cultures

Background: The poor prognosis for glioblastoma patients is caused by the diffuse infiltrative growth pattern of the tumor. Therefore, the molecular and cellular processes underlying cell migration continue to be a major focus of glioblastoma research. Emerging evidence supports the concept that the tumor microenvironment has a profound influence on the functional properties of tumor cells. Accordingly, substantial effort must be devoted to move from traditional two-dimensional migration assays to three-dimensional systems that more faithfully recapitulate the complex in vivo tumor microenvironment. Methods: In order to mimic the tumor microenvironment of adult gliomas, we used adult organotypic brain slices as an invasion matrix for implanted, fluorescently labeled tumor spheroids. Cell invasion was imaged by confocal or epi-fluorescence microscopy and quantified by determining the average cumulative sprout length per spheroid. The tumor microenvironment was manipulated by treatment of the slice with small molecule inhibitors or using different genetically engineered mouse models as donors. Results: Both epi-fluorescence and confocal microscopy were applied to precisely quantify cell invasion in this ex vivo approach. Usage of a red-emitting membrane dye in addition to tissue clearing drastically improved epi-fluorescence imaging. Preparation of brain slices from of a genetically engineered mouse with a loss of a specific cell surface protein resulted in significantly impaired tumor cell invasion. Furthermore, jasplakinolide treatment of either tumor cells or brain slice significantly reduced tumor cell invasion. Conclusion: We present an optimized invasion assay that closely reflects in vivo invasion by the implantation of glioma cells into organotypic adult brain slice cultures with a preserved cytoarchitecture. The diversity of applications including manipulation of the tumor cells as well as the microenvironment, permits the investigation of rate limiting factors of cell migration in a reliable context. This model will be a valuable tool for the discovery of the molecular mechanisms underlying glioma cell invasion and, ultimately, the development of novel therapeutic strategies

Artemin and an Artemin-Derived Peptide, Artefin, Induce Neuronal Survival, and Differentiation Through Ret and NCAM

Artemin (ARTN) is a neurotrophic factor from the GDNF family ligands (GFLs) that is involved in development of the nervous system and neuronal differentiation and survival. ARTN signals through a complex receptor system consisting of the RET receptor tyrosine kinase and a glycosylphosphatidylinositol-anchored co-receptor GFL receptor α, GFRα3. We found that ARTN binds directly to neural cell adhesion molecule (NCAM) and that ARTN-induced neuritogenesis requires NCAM expression and activation of NCAM-associated signaling partners, thus corroborating that NCAM is an alternative receptor for ARTN. We designed a small peptide, artefin, that could interact with GFRα3 and demonstrated that this peptide agonist induces RET phosphorylation and mimics the biological functions of ARTN – neuroprotection and neurite outgrowth. Moreover, artefin mimicked the binding of ARTN to NCAM and required NCAM expression and activation for its neurite elongation effect, thereby suggesting that artefin represents a binding site for NCAM within ARTN. We showed that biological effects of ARTN and artefin can be inhibited by abrogation of both NCAM and RET, suggesting a more complex signaling mechanism that previously thought. As NCAM plays a significant role in neurodevelopment, regeneration, and synaptic plasticity we suggest that ARTN and its mimetics are promising candidates for treatment of neurological disorders and warrant further investigations

eGeo-Riddle - videounterstützte eExkursionen zur Physischen Geographie

Der Artikel zeigt neue multimediale Kommunikationswege und Lernstrategien für eine moderne Hochschullehre auf, wie Vorlesungsinhalte aus der Physischen Geographie mit Hilfe von eExkursionen ortsbezogen vermittelt werden und für mobile Endgeräte digital abrufbar gemacht werden können. E-Learning wird mit praktischer Exkursionsarbeit und multimedialer Umweltbildung vor Ort verknüpft und dient als Baustein für mobile und flexible Lernprozesse. Das Konzept bietet ein nachhaltiges und zusätzliches Lehrangebot von und für Geographiestudierende im Gelände. Es ist auf alle Vorlesungsinhalte mit einem räumlichen Bezug übertragbar. 24.04.2014 | Elisa Michel, Tanja Decrouppé & Jochen Wiesner (Bochum