Über die Eignung ein- und zehnjährigen Pappelholzes zur Zellstoffgewinnung

Zusammenfassung Auszug aus dem Schrifttum. Morphologie der Pappelholzfasern. Chemische Untersuchung ein- und zehnj?hrigen Pappelholzes. Vergleich mit anderen H?lzern. Aufschlu?versuche nach dem Sulfat- und Sulfitverfahren. Erkl?rung für die sehr hohe Festigkeit der Pappelholz-Sulfatzellstoffe. Zusammenfassung. 10. Mitteilung aus dem Institut für Zellstoff- und Papierchemie, Darmstadt.     

Biopolymers as green-based food packaging materials: A focus on modified and unmodified starch-based films

The ideal food packaging materials are recyclable, biodegradable, and compostable. Starch from plant sources, such as tubers, legumes, cereals, and agro-industrial plant residues, is considered one of the most suitable biopolymers for producing biodegradable films due to its natural abundance and low cost. The chemical modification of starch makes it possible to produce films with better technological properties by changing the functional groups into starch. Using biopolymers extracted from agro-industrial waste can add value to a raw material that would otherwise be discarded. The recent COVID-19 pandemic has driven a rise in demand for single-use plastics, intensifying pressure on this already out-of-control issue. This review provides an overview of biopolymers, with a particular focus on starch, to develop sustainable materials for food packaging. This study summarizes the methods and provides a potential approach to starch modification for improving the mechanical and barrier properties of starch-based films. This review also updates some trends pointed out by the food packaging sector in the last years, considering the impacts of the COVID-19 pandemic. Perspectives to achieve more sustainable food packaging toward a more circular economy are drawn.     

Linear-time algorithms for eliminating claws in graphs

Since many -complete graph problems are polynomial-time solvable when restricted to claw-free graphs, we study the problem of determining the distance of a given graph to a claw-free graph, considering vertex elimination a measure. Claw-free Vertex Deletion (CFVD) consists of determining the minimum number of vertices to be removed from a graph such that the resulting graph is claw-free. Although CFVD is -hard in general and recognizing claw-free graphs is still a challenge, where the current best deterministic algorithm for a graph G consists of performing executions of the best algorithm for matrix multiplication, we present linear-time algorithms for CFVD on weighted block graphs and weighted graphs with bounded treewidth. Furthermore, we show that this problem on forests can be solved in linear time by a simpler algorithm, and we determine the exact values for full k-ary trees. On the other hand, we show that CFVD is -hard even when the input graph is a split graph. We also show that the problem is hard to be approximated within any constant factor better than 2, assuming the unique games conjecture.     

Mannosylerythritol lipids as green pesticides and plant biostimulants

Biosurfactants can be applied in the formulation of personal care products, as food additives, and as biocontrol agents in the agricultural sector. Glycolipids and lipopeptides represent an important group of microbial-based biosurfactants with biostimulating properties. Among them, the mannosylerythritol lipids also presented antimicrobial activity, mostly against Gram-positive bacteria and phytopathogenic fungi. In this sense, mannosylerythritol lipids are a potential safer green alternative for partially replacing synthetic pesticides. This review aimed to critically discuss the current state of the art and future trends of mannosylerythritol lipids as green pesticides and biostimulants for seed germination and plant growth. Due to their chemical structure, mannosylerythritol lipids are likely related to energy pathways such as glycolysis and Krebs cycle, i.e. a direct cellular biostimulant potential. In this case, experimental evidence from other glycolipids indicated that structural and chemical changes as a potential drug vehicle due to morphological changes caused by biosurfactant–membrane interaction. In addition, like other biosurfactants, mannosylerythritol lipids can trigger self-defense mechanisms, leading to a lower frequency of phytopathogen infections. Therefore, mannosylerythritol lipids have the potential for biostimulation and antiphytopathogenic action, despite that to date no data are available on mannosylerythritol lipids as biostimulants and green pesticides simultaneously. Based on the current state of the art, mannosylerythritol lipids have great potential for a biotechnological advance toward more sustainable agriculture. © 2022 Society of Chemical Industry.     

Material Articulation: Computing and Constructing Continuous Differentiation

Free-form geometric designs make use of continuously differentiated components that exist within a multidimensional envelope of material performance, fabrication capabilities, logistics and cost. In this article, Cristiano Ceccato explains how geometric form-rationalisation and analysis of constructability at the functional as well as the computational level form the basis for achieving advanced designs in terms of articulation of material through mass-customised industrial production. Taking examples from the current work of Zaha Hadid Architects (ZHA), he presents a necessarily evolving framework of computational design and associated practice of architecture that is attempting to close the gaps between computational design, digitally controlled manufacturing and evolving mechanisms of contemporary construction and project delivery. Copyright © 2012 John Wiley & Sons, Ltd.     

Comparison between line and surface integral formulations of the hybrid mode‐matching/two‐dimensional finite element method

The hybrid mode‐matching/two‐dimensional‐finite‐element (MM/FEM2D) technique has been proposed for the analysis of discontinuities with waveguides of arbitrary cross section; this technique combines the computational efficiency of modal analysis with the versatility and flexibility of the FEM approach. In this paper, we present in detail a surface‐integrals and a line‐integrals formulation of the hybrid MM/FEM2D technique, in case the ‘Standard Formulation’ is used as FEM2D formulation. Such formulations allow computing analytically both the normalization and the coupling integrals. Furthermore, we compare the accuracy obtained by using the line‐integrals and the corresponding surface‐integrals formulation. To these aims we present several numerical results. Copyright © 2004 John Wiley & Sons, Ltd.     

Synthesis,Characterization, and Biological Activity Evaluation of Magnetite-Functionalized Eugenol

This work reports the magnetite-functionalization and biological evaluation of eugenol by the co-precipitation method employed only Fe²⁺ under mild conditions and control from the amount of the incorporated magnetite. Magnetic nanoparticles were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR), hydrodynamic size distribution (Zetasizer), and vibrating sample magnetometer (VSM). SEM images showed that EUG·Fe₃O₄ similar in shape to a nanoflower. The FTIR spectrum confirmed the presence of characteristic EUG and Fe₃O₄ bands in the EUG·Fe₃O₄ sample, the XRD analysis showed that the magnetite functionalization with eugenol slightly affected the Fe₃O₄ crystal structure, while the VSM measurements demonstrate that EUG·Fe₃O₄ 1:1 shows a superparamagnetic behavior, suggesting small non-interacting particles. The in vitro safety profile and cytotoxicity of free eugenol, magnetite pristine, EUG·Fe₃O₄ 1:1, EUG·Fe₃O₄ 1:5, and EUG·Fe₃O₄ 1:10 was investigated using human cell lines (keratinocytes and melanoma). The results demonstrate the high biocompatibility of EUG·Fe₃O₄ in HaCat cells and the greater specificity for the A375 cell line. Furthermore, the magnetite-functionalization with eugenol decreased the toxic effects of free eugenol on healthy cells. Antibacterial tests were performed in different bacterial strains. The experimental data showed that among the magnetic compounds, the microorganisms were only sensitive to treatment with EUG·Fe₃O₄ 1:1. Regarding the antibiofilm activity assay, it can be observed that only the EUG·Fe₃O₄ caused a significant decrease in biomass when compared to the positive control. Finally, it can be concluded that EUG·Fe₃O₄ proves to be a potential candidate for future studies for drug delivery of cancer and bacterial infections treatments.

Graphical Abstract

     

A combined approach for improving humanoid robots autonomous cognitive capabilities

Recent technologies advancements promise to change our lives dramatically in the near future. A new different living society is progressively emerging, witnessed from the conception of novel digital ecosystems, where humans are expected to share their own spaces and habits with machines. Humanoid robots are more and more being developed and provided with enriched functionalities; however, they are still lacking in many ways. One important goal in this sense is to enrich their cognitive capabilities, to make them more “intelligent” in order to better support humans in both daily and special activities. The goal of this research is to set a step in bridging the gap between symbolic AI and connectionist approaches in the context of knowledge acquisition and conceptualization. Hence, we present a combined approach based on semantics and machine learning techniques for improving robots cognitive capabilities. This is part of a wider framework that covers several aspects of knowledge management, from representation and conceptualization, to acquisition, sharing and interaction with humans. Our focus in this work is in particular on the development and implementation of techniques for knowledge acquisition. Such techniques are discussed and validated through experiments, carried out on a real robotic platform, showing the effectiveness of our approach. The results obtained confirmed that the combination of the approaches gives superior performance with respect to when they are considered individually.