266 research outputs found

    Composite Phaseolus vulgaris plants with transgenic roots as research tool

    Get PDF
    Large seeded grain legumes such as the common bean (Phaseolus vulgaris) and cowpea (Vigna unguiculata) are very important crops with seeds that are major protein source for people in developingcountries, but their yields and improvement lag behind the economically more important cereals. For research purposes, genetic transformation is a powerful tool to obtain valuable information on gene expression and putative gene functions. In addition, through genetic transformation, candidate genes can be evaluated for their potential in agricultural biotechnology applications, such as resistance against biotic stresses. However, it remains difficult to stable genetically transform large seeded grain legumes such as Phaseolus and cowpea using Agrobacterium tumefaciens. In this paper a system is described to obtain so-called transgenic composite plants from P. vulgaris. These have a transgenic root system, obtained through Agrobacterium rhizogenes transformation of de-rooted seedlings. Their potentials for studies on important processes in the root system will be discussed

    Potential merits for space robotics from novel concepts of actuation for soft robotics

    Get PDF
    Autonomous robots in dynamic and unstructured environments require high performance, energy efficient and reliable actuators. In this paper we give an overview of the first results of two lines of research regarding the novel actuation principle we introduced: Series-Parallel Elastic Actuation (SPEA). Firstly, we introduce the SPEA concept and present first prototypes and results. Secondly, we discuss the potential of self-healing materials in robotics, and discuss the results on the first self-healing pneumatic cell and selfhealing mechanical fuse. Both concepts have the potential to improve performance, energy efficiency and reliability

    The Role of Cu-Based Intermetallic on the Direct Growth of a ZnAl LDH Film on AA2024

    Get PDF
    The direct ZnAl layered double hydroxide growth on AA2024 is a fast-occurring reaction, yet is characterized by an inhomogeneous film thickness. It has been shown that at the periphery of Cu-rich intermetallic, the flakes tend to be larger and denser. A combination of in situ and ex situ measurements were used to monitor the changes in the layered double hydroxide film grown on the regions of intermetallics. Immediately after immersion, an activation of the intermetallic phases is observed due to the dealloying process with an almost immediate film growth. Dealloying is followed by trenching of the adjacent Al matrix leading to an excessive production of large and dense layered double hydroxide flakes at the periphery of the intermetallic. However, the scanning electron microscopy cross-section images revealed that the trenching process leads to defects in the area surrounding the intermetallic. This could weaken the corrosion resistance performance of the layered double hydroxide conversion coating and lead to adhesion failure of consecutive polymer coatings. Nevertheless, this work highlights a few advantages and drawbacks of the layered double hydroxide conversion coatings and pathways to its potential optimization and improvement

    Оцінка якості життя у вікових першовагітних та вагітних з великим інтергенетичним інтервалом

    Get PDF
    Проведено изучение показателей качества жизни у 120 возрастных первобеременных и 240 беременных с большим интергенетическим интервалом с использованием опросника SF-36 Health Status Survey, разработанного The Health Institute, New England Medical Center, Boston, USA. Исследование показало, что пациентки обеих групп имеют низкие показатели качества жизни. При сравнении большинство изучаемых параметров оценки качества жизни в обследованных группах не отличались, однако у пациенток с большим интергенетическим интервалом – достоверно выше оценка социальной роли и энергетичности. Оценка качества жизни у возрастных первобеременных и беременных с большим интергенетическим интервалом является важным сегментом наблюдения во время беременности, который оценивает перспективы развития беременности в психологическом, физическом и социальном аспектах.A study of the life quality of 120 over-age primigravidas and of 240 women with a large intergenetic interval has been carried out using the questionnaire SF-36 Health Status Survey developed by The Health Institute, New England Medical Center, Boston, USA. This research has shown that the patients in the both groups have a low quality of life. The major part of the life quality parameters were the same in the both groups, however, in patients with a large interval between births the values of the social role and the energy level were significantly higher. The life quality of over-age primigravidas and pregnant women with a large interval between successive births is an important sector of observation during pregnancy, which allows assessing the prospects of pregnancy in the psychological, physical, and social aspects

    Bioinspired Nanofeatured Substrates: Suitable Environment for Bone Regeneration.

    Get PDF
    Bone mimicking coatings provide a complex microenvironment in which material, through its inherent properties (such as nanostructure and composition), affects the commitment of stem cells into bone lineage and the production of bone tissue regulating factors required for bone healing and regeneration. Herein, a bioactive mineral/biopolymer composite made of calcium phosphate/chitosan and hyaluronic acid (CaP-CHI-HA) was elaborated using a versatile simultaneous spray coating of interacting species. The resulting CaP-CHI-HA coating was mainly constituted of bioactive, carbonated and crystalline hydroxyapatite with 277 ± 98 nm of roughness, 1 μm of thickness, and 2.3 ± 1 GPa of stiffness. After five days of culture, CaP-CHI-HA suggested a synergistic effect of intrinsic biophysical features and biopolymers on stem cell mechanobiology and nuclear organization, leading to the expression of an early osteoblast-like phenotype and the production of bone tissue regulating factors such as osteoprotegerin and vascular endothelial growth factor. More interestingly, amalgamation with biopolymers conferred to the mineral a bacterial antiadhesive property. These significant data shed light on the potential regenerative application of CaP-CHI-HA bioinspired coating in providing a suitable environment for stem cell bone regeneration and an ideal strategy to prevent implant-associated infections.journal article2017 Apr 122017 03 30importe

    Self-healing materials for soft-matter machines and electronics

    Get PDF
    The emergence of soft machines and electronics creates new opportunities to engineer robotic systems that are mechanically compliant, deformable, and safe for physical interaction with the human body. Progress, however, depends on new classes of soft multifunctional materials that can operate outside of a hard exterior and withstand the same real-world conditions that human skin and other soft biological materials are typically subjected to. As with their natural counterparts, these materials must be capable of self-repair and healing when damaged to maintain the longevity of the host system and prevent sudden or permanent failure. Here, we provide a perspective on current trends and future opportunities in self-healing soft systems that enhance the durability, mechanical robustness, and longevity of soft-matter machines and electronics

    Morphology and microstructure evolution of gold nanostructures in the limited volume porous matrices

    Get PDF
    The modern development of nanotechnology requires the discovery of simple approaches that ensure the controlled formation of functional nanostructures with a predetermined morphology. One of the simplest approaches is the self-assembly of nanostructures. The widespread implementation of self-assembly is limited by the complexity of controlled processes in a large volume where, due to the temperature, ion concentration, and other thermodynamics factors, local changes in diffusion-limited processes may occur, leading to unexpected nanostructure growth. The easiest ways to control the diffusion-limited processes are spatial limitation and localized growth of nanostructures in a porous matrix. In this paper, we propose to apply the method of controlled self-assembly of gold nanostructures in a limited pore volume of a silicon oxide matrix with submicron pore sizes. A detailed study of achieved gold nanostructures’ morphology, microstructure, and surface composition at different formation stages is carried out to understand the peculiarities of realized nanostructures. Based on the obtained results, a mechanism for the growth of gold nanostructures in a limited volume, which can be used for the controlled formation of nanostructures with a predetermined geometry and composition, has been proposed. The results observed in the present study can be useful for the design of plasmonic-active surfaces for surface-enhanced Raman spectroscopy-based detection of ultra-low concentration of different chemical or biological analytes, where the size of the localized gold nanostructures is comparable with the spot area of the focused laser beam. © 2020 by the authors. Licensee MDPI, Basel, Switzerland.3.1.5.1Ministry of Education and Science of the Russian Federation, Minobrnauka: К-2018-036, N 211Russian Foundation for Fundamental Investigations, RFFI: 19-32-50058European Commission, ECMinistry of Science and Technology, MOSTFunding: This research was funded by H2020-MSCA-RISE2017-778308-SPINMULTIFILM Project, the scientific– technical program, ‘Technology-SG’ [project number 3.1.5.1], Ministry of Education and Science of the Russian Federation in the framework of Increase Competitiveness Program of NUST «MISiS» [№ К-2018-036], implemented by a governmental decree dated 16th of March 2013, N 211 and Russian Foundation for Fundamental Investigations [project number 19-32-50058].Acknowledgments: D.V.Y. greatly acknowledges the World Federation of Scientists National Scholarship Program. E.Yu.K., D.V.Y., V.D.B., and V.S. greatly acknowledge the European Union program Mobility Scheme for Targeted People-to-People-Contacts (MOST) for supporting research visits

    Particulate barium tracing of significant mesopelagic carbon remineralisation in the North Atlantic

    Get PDF
    The remineralisation of sinking particles by prokaryotic heterotrophic activity is important for controlling oceanic carbon sequestration. Here, we report mesopelagic particulate organic carbon (POC) remineralisation fluxes in the North Atlantic along the GEOTRACES-GA01 section (GEOVIDE cruise; May-June 2014) using the particulate biogenic barium (excess barium; Baxs/ proxy. Important mesopelagic (100-1000 m) Baxs differences were observed along the transect depending on the intensity of past blooms, the phytoplankton community structure, and the physical forcing, including downwelling. The subpolar province was characterized by the highest mesopelagic Baxs content (up to 727 pmol L-1/, which was attributed to an intense bloom averaging 6 mg chl a m-3 between January and June 2014 and by an intense 1500m deep convection in the central Labrador Sea during the winter preceding the sampling. This downwelling could have promoted a deepening of the prokaryotic heterotrophic activity, increasing the Baxs content. In comparison, the temperate province, characterized by the lowest Baxs content (391 pmol L-1/, was sampled during the bloom period and phytoplankton appear to be dominated by small and calcifying species, such as coccolithophorids. The Baxs content, related to oxygen consumption, was converted into a remineralisation flux using an updated relationship, proposed for the first time in the North Atlantic. The estimated fluxes were of the same order of magnitude as other fluxes obtained using independent methods (moored sediment traps, incubations) in the North Atlantic. Interestingly, in the subpolar and subtropical provinces, mesopelagic POC remineralisation fluxes (up to 13 and 4.6 mmol Cm-2 d-1, respectively) were equalling and occasionally even exceeding upper-ocean POC export fluxes, deduced using the 234Th method. These results highlight the important impact of the mesopelagic remineralisation on the biological carbon pump of the studied area with a near-zero, deep (> 1000 m) carbon sequestration efficiency in spring 2014
    corecore