The influence of topographic microstructures on the initial adhesion of L929 fibroblasts studied by single-cell force spectroscopy

Single-cell force spectroscopy was used to investigate the initial adhesion of L929 fibroblasts onto periodically grooved titanium microstructures (height ~6 μm, groove width 20 μm). The position-dependent local adhesion strength of the cells was correlated with their rheological behavior. Spherical cells exhibited a significantly lower Young’s modulus (<1 kPa) than that reported for spread cells, and their elastic properties can roughly be explained by the Hertz model for an elastic sphere. While in contact with the planar regions of the substrate, the cells started to adapt their shape through slight ventral flattening. The process was found to be independent of the applied contact force for values between 100 and 1,000 pN. The degree of flattening correlated with the adhesion strength during the first 60 s. Adhesion strength can be described by fast exponential kinetics as \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$C_{1} \left[ {1 - \exp \left( { - C_{2} \cdot t} \right)} \right]$$\end{document} with C1 = 2.34 ± 0.19 nN and C2 = 0.09 ± 0.02 s−1. A significant drop in the adhesion strength of up to 50% was found near the groove edges. The effect can be interpreted by the geometric decrease of the contact area, which indicates the inability of the fibroblasts to adapt to the shape of the substrate. Our results explain the role of the substrate’s topography in contact guidance and suggest that rheological cell properties must be considered in cell adhesion modeling

Ethylene-responsive element binding protein (EREBP) expression and the transcriptional regulation of class I β-1,3-glucanase during tobacco seed germination

Class I β-1,3-glucanase (βGLU I) is transcriptionally induced in the micropylar endosperm just before its rupture prior to the germination (i.e. radicle emergence) of Nicotiana tabacum L. cv. ‘Havana 425' seeds. Ethylene is involved in endosperm rupture and high-level βGLU I expression; but, it does not affect the spatial and temporal pattern of βGLU I expression. A promoter deletion analysis of the tobacco βGLU I B gene suggests that (1) the distal −1452 to −1193 region, which contains the positively acting ethylene-responsive element (ERE), is required for high-level, ethylene-sensitive expression, (2) the regions −1452 to −1193 and −402 to 0 contribute to down-regulation by abscisic acid (ABA), and (3) the region −402 to −211 is necessary and sufficient for low-level micropylar-endosperm-specific expression. Transcripts of the ERE-binding proteins (EREBPs) showed a novel pattern of expression during seed germination: light or gibberellin was required for EREBP-3 and EREBP-4 expression; EREBP-4 expression was constitutive and unaffected by ABA or ethylene; EREBP-3 showed transient induction just before endosperm rupture, which was earlier in ethylene-treated seeds and inhibited by ABA. No expression of EREBP-1 and EREBP-2 was detected. In contrast to βGLU I, EREBP-3 and EREBP-4 were not expressed specifically in the micropylar endosperm. The results suggest that transcriptional regulation of βGLU I could depend on: activation of ethylene signalling pathways acting via EREBP-3 with the ERE as the target, and ethylene-independent signalling pathways with targets in the proximal promoter region that are likely to determine spatial and temporal patterns of expressio

Kulturtourismus – Rittergüter und Herrenhäuser im Kohrener Land und in der Region Leipzig

Die Region Leipzig weist eine hohe Dichte an Burgen, Schlössern und Herrenhäusern auf. Jedoch bleiben viele, besonders die kleinen historischen Bauten dem kulturhistorisch interessierten Gast verborgen. Sie werden beim Durchqueren der Lande auf den ersten Blick nicht wahrgenommen und sind zumeist in keinen touristischen Broschüren verortet. Diesen geschichtsprägenden Herrensitzen soll anhand der vorliegenden Karte die gebührende Aufmerksamkeit geschenkt werden. Der Auto-, Rad- und Fußwanderer erhält damit einen Überblick über eine besondere Sachgruppe des reichen kulturellen Erbes, das gleichrangig neben den bekannten touristischen Anziehungspunkten, wie Dome, Klöster, Kirchen, städtebauliche Ensembles, technische Denkmale oder auch Gaststätten rangiert: die ehemaligen Rittergüter. Im gesamten Untersuchungsgebiet gibt es über 200 Objekte in unterschiedlichen baulichen Zuständen und mit diversen Nutzungskonzepten. Die Redaktion wird die umfangreichen Recherchearbeiten weiterführen, um das Thema Interessierten zugänglich zu machen

The influence of the governance and innovation indexes on the environmental performance of countries

In a period marked by ascending international independence and integration, governance and innovation are considered important tools in the sustainable growing process of countries, highlighting a constant search for positive development. The present paper intends to analyze the influence of the innovation and governance indexes on the environmental performance of nations around the globe. This is a descriptive study, we chose a quantitative approach and the data were collected on the Worldwide Governance Indicators (2018), Global Innovation Index (2018) and Environmental Performance Index (2018) websites. Subsequently, the data were organized and tabulated on the software SPSS®, version 22. Our analysis happened with the aid of descriptive statistics and linear regression. The main results indicate that countries do not show better environmental performance - where we take environmental health and the vitality of the ecosystems into consideration - due to the confidence and respect to the process in which governments are elected and observed.  In the innovation perspective and context, we could infer that it influences the environmental performance among the 108 countries that compose the sample. Therefore, the opinion regarding the importance of innovation is essential to comprehend the development of countries, and that includes the environmental field

Evidence for a role of β‐1,3‐glucanase in dicot seed germination

Class I β‐1,3‐glucanases are antifungal vacuolar proteins implicated in plant defense that show developmental, hormonal, and pathogenesis‐related regulation. The expression was studied in germinating tobacco seeds of a chimeric β‐glucuronidase (GUS) reporter gene fused to 1.6 kb of the 5′ flanking sequence of the tobacco class I β‐1,3‐glucanase B (GLB) promoter. Histological staining for GUS activity showed that expression of the GLB promoter is highly localized in a specific zone of the endosperm in germinating seeds. The temporal and spatial patterns of GUS and β‐1,3‐glucanase activity found, suggest a novel function for class I β‐1,3‐glucanases during seed germination in a dicotyledonous plant. Copyright © 1994, Wiley Blackwell. All rights reserve

Increased abundance of MTD1 and MTD2 mRNAs in nodules of decapitated Medicago truncatula.

To gain insight into the molecular processes occurring in root nodule metabolism after stress, we used a mRNA differential display (DDRT-PCR) approach to identify cDNAs corresponding to genes whose expression is enhanced in nodules of decapitated Medicago truncatula plants. Two full-length cDNAs of plant origin were isolated (MTD1 and MTD2). Sequence analysis revealed that MTD1 is identical to an EST clone (accession number AW559774) expressed in roots of M. truncatula upon infection with Phytophthora medicaginis, while MTD2 is highly homologous to an Arabidopsis thaliana gene (accession number AL133292) coding for a RNA binding-like protein. The two mRNAs started to accumulate in root nodules at 4 h after plant decapitation and reached even higher transcript levels at 24 h from the imposition of the treatment. MTD1 and MTD2 mRNAs were mainly induced in nodules, with very little induction in roots. The abundance of the two transcripts did not change in response to other perturbations known to decrease nitrogenase activity, such as nitrate and Ar/O2 treatments. Our results suggest that MTD1 and MTD2 represent transcripts that accumulate locally in nodules and may be involved in changes in nodule metabolism in response to decapitation

Os aprendizes marinheiros no Paraná oitocentista

This work pinpoints the vicissitudes experienced by boys concerning the learning of a sailor’s job, after the creation of the ‘Companhia de Aprendizes Marinheiros’ (Company of Apprentice Sailors) in Paraná-Brazil, in 1864. Recruited among poor children, mainly orphans, the apprentices were given basic school, and professional instruction. This educational process is discussed according to the guidelines of the work society in nineteenth-century Brazil. This work also addresses the limitations imposed on the learning of a job under adverse conditions regarding the survival and health conditions of the conscripted boys. The conscript many times ocurred illegally and the boys were considered ugly and wicked by those who conscripted them.O trabalho aponta as vicissitudes do aprendizado dos ofícios do mar vivenciado por meninos, após a criação da Companhia de Aprendizes Marinheiros no Paraná-Brasil, em 1864. Recrutados entre crianças pobres, especialmente órfãs, os aprendizes passavam por uma educação tanto em nível elementar quanto profissional. Essa formação é discutida à luz das propostas de constituição da sociedade do trabalho no Brasil, daqueles tempos. Revelam-se, ademais, as limitações impostas ao aprendizado de um ofício em condições adversas no que diz respeito à sobrevivência e condições de saúde desses meninos alistados, muitas vezes ilegalmente, considerados feios e malvados por aqueles que os recrutavam

Simulation of the Electric Field Distribution Near a Topographically Nanostructured Titanium-Electrolyte Interface: Influence of the Passivation Layer

A major challenge in biomaterials research is the regulation of protein adsorption at metallic implant surfaces. Recently, a number of studies have shown that protein adsorption can be influenced by metallic nanotopographies, which are discussed to increase electric field strengths near sharp edges and spikes. Since many metallic biomaterials form a native passivation layer with semiconducting properties, we have analyzed the influence of this layer on the near-surface electric field distribution of a nanostructure using finite element simulations. The Poisson-Boltzmann equation was solved for a titanium nanostructure covered by a TiO2 passivation layer in contact with a physiological NaCl solution (bulk concentration 0.137 mol/L). In contrast to a purely metallic nanostructure, the electric field strengths near sharp edges and spikes can be lower than in planar regions if a passivation layer is considered. Our results demonstrate that the passivation layer has a significant influence on the near-surface electric field distribution and must be considered for theoretical treatments of protein adsorption on passivated metals like titanium

Coagulation using organic carbonates opens up a sustainable route towards regenerated cellulose films

Due to their biodegradability, biocompatibility and sustainable nature, regenerated cellulose (RC) films are of enormous relevance for green applications including medicinal, environmental and separation technologies. However, the processes used so far are very hazardous to the environment and health. Here, we disclose a simple, fast, environmentally friendly, nontoxic and cost-effective processing method for preparing RC films. High quality non-transparent and transparent RC films and powders can be produced by dissolution with tetrabutylphosphonium hydroxide [TBPH]/[TBP]+[OH]− followed by coagulation with organic carbonates. Investigations on the coagulation mechanism revealed an extremely fast reaction between the carbonates and the hydroxide ions. The high-quality powders and films were fully characterized with respect to structure, surface morphology, permeation and selectivity. This method represents a future-oriented green alternative to known industrial processes. © 2020, The Author(s)