347 research outputs found
MANAJEMEN PRODUKSI PENANGKAPAN IKAN NELAYAN DI KELURAHAN TONDONGGEU KECAMATAN NAMBO KOTA KENDARI PERSPEKTIF EKONOMI ISLAM
This research aims to analyze the management of fish production by fishermen in Tondonggeu Village, Nambo District, Kendari City, from the perspective of Islamic Economics. This qualitative study used methods such as observation, interviews, and documentation for data collection. Data analysis included data reduction, presentation, drawing conclusions, and validating the data through source, technical, and time triangulation. The findings indicate that production management in Tondonggeu Village involves functions like planning, organizing, directing, and controlling the production process. Furthermore, when viewed through an Islamic economic lens, production management aligns with principles such as using simple and eco-friendly fishing equipment and marketing catches without harmful chemicals
Mechanical design and friction modelling of a cable-driven upper-limb exoskeleton
This paper presents a lightweight and low-inertia cable-driven upper-limb exoskeleton powerful enough to meet the requirements for activities of daily living. It presents the mechanical design, kinematic structure,the underlying actuation system, sensors, other electronic components as well as the controller of the exoskeleton.
The extensive effect of friction on cable-driven designs, such as the one presented in this paper, requires proper mathematical modelling for controller design. Thus, we propose a current actuator model that describes the relationship between the motor current, velocity, and external load. The model relies on an underlying Stribeck+Coulomb friction representation and an additional parameter that modifies its Coulomb friction representation with an offset to represent adhesion between a cable and sheath.
The model has been validated based on experimental data collected with the exoskeleton. The results show that the proposed model better captures the non-linear behaviour of the exoskeletonâs actuation system, increasing overall descriptive performance by 15%. However, adding the adhesion offset to extend the relation of static friction, does not improve the model
Using humanoid robots to study human behavior
Our understanding of human behavior advances as our humanoid robotics work progresses-and vice versa. This team's work focuses on trajectory formation and planning, learning from demonstration, oculomotor control and interactive behaviors. They are programming robotic behavior based on how we humans âprogramâ behavior in-or train-each other
Using 3D gastrointestinal tract in vitro models with microfold cells and mucus secreting ability to assess the hazard of copper oxide nanomaterials
Abstract:
Background: Copper oxide nanomaterials (CuO NMs) are exploited in many products including inks, cosmetics,
textiles, wood preservatives and food contact materials. Their incorporation into these products may enhance oral
exposure in consumer, environmental and occupational settings. Undifferentiated and differentiated monocultures of
Caco-2 cells are commonly used to assess NM toxicity to the intestine in vitro. However, the integration of other cell
types into Caco-2 in vitro models increases their physiological relevance. Therefore, the aim of this study is to evaluate
the toxicity of CuO NMs and copper sulphate (
CuSO4) to intestinal microfold (M) cell (Caco-2/Raji B) and mucus secreting
(Caco-2/HT29-MTX) co-culture in vitro models via assessment of their impact on barrier integrity, viability and
interleukin (IL)-8 secretion. The translocation of CuO NMs and CuSO4
across the intestinal barrier was also investigated
in vitro.
Results: CuO NMs and CuSO4
impaired the function of the intestinal barrier in the co-culture models [as indicated by
a reduction in transepithelial electrical resistance (TEER) and Zonular occludens (ZO-1) staining intensity]. Cu translocation
was observed in both models but was greatest in the Caco-2/Raji B co-culture. CuO NMs and CuSO4
stimulated
an increase in IL-8 secretion, which was greatest in the Caco-2/HT29-MTX co-culture model. CuO NMs and CuSO4
did not stimulate a loss of cell viability, when assessed using light microscopy, nuclei counts and scanning electron
microscopy. CuO NMs demonstrated a relatively similar level of toxicity to CuO4
in both Caco-2/Raji B and Caco-2/
HT29-MTX co- culture models.
Conclusions: The Caco-2/Raji B co-culture model was more sensitive to CuO NM and CuSO4
toxicity than the
Caco-2/HT29-MTX co-culture model. However, both co-culture models were less sensitive to CuO NM and CuSO4
toxicity than simple monocultures of undifferentiated and differentiated Caco-2 cells, which are more routinely used
to investigate NM toxicity to the intestine. Obtained data can therefore feed into the design of future studies which
assess the toxicity of substances (e.g. NMs) and pathogens to the intestine (e.g. by informing model and endpoint
selection). However, more testing with a wider panel of NMs would be beneficial in order to help select which in vitro
models and endpoints to prioritise when screening the safety of ingested NMs. Comparisons with in vivo findings will
also be essential to identify the most suitable in vitro model to screen the safety of ingested NMs
Investigation and evaluation of a 3D-printed optical modified cultivation vessel for improved scattered light measurement of biotechnologically relevant organisms
In the field of bioprocess development miniaturization, parallelization and flexibility play a key role reducing costs and time. To precisely meet these requirements, additive manufacturing (3D-printing) is an ideal technology. 3D-printing enables rapid prototyping and cost-effective fabrication of individually designed devices with complex geometries on demand. For successful bioprocess development, monitoring of process-relevant parameters, such as pH, dissolved oxygen (DO), and biomass, is crucial. Online monitoring is preferred as offline sampling is time-consuming and leads to loss of information. In this study, 3D-printed cultivation vessels with optical prisms are evaluated for the use in upstream processes of different industrially relevant microorganisms and cell lines. It was shown, that the 3D-printed optically modified well (OMW) is of benefit for a wide range of biotechnologically relevant microorganisms and even for mammalian suspension cells. Evaluation tests with Escherichia coli, Bacillus subtilis, Saccharomyces cerevisiae, and Chinese hamster ovary (CHO) cells were performed, providing highly reproducible results. Growth behavior of OMW cultures was comparable to behavior of shake flask (SF) cultivations and the signal to noise ratio in online biomass measurement was shown to be reduced up to 95.8% by using the OMW. Especially the cultivation phases with low turbidity respective optical densities below 1.0 rel.AU could be monitored accurately for the first time. Furthermore, it was demonstrated that the 3D-printed optics are transferable to different well geometries and sizes, enabling efficient biomass monitoring for individual requirements with tailor-made 3D-printed cultivation vessels in small scale
Analysis of genetic diversity in accessions of Irvingia gabonensis (Aubry-Lecomte ex O'Rorke) Baill
Amplified fragment length polymorphism (AFLP) was used to assess genetic diversity and relationships among 15 accessions of Irvingia gabonensis collected from Cameroun, Gabon, and Nigeria. Twelve AFLP+3 primers produced 384 polymorphic fragments. Average genetic distance (AGD) between the 15 accessions was 58.7% (32-88%). AGD and range of genetic distance among accessions from Cameroun, Nigeria and Gabon were 62% (53-76%), 52% (32.3 â 84.8%) and 50% (45- 53%), respectively, indicating more genetic diversity in Cameroun than Nigeria and Gabon. The unweighted pair-group method of the arithmetic average (UPGMA) and principal coordinate analysis (PCO) showed a clear distinction between the Gabon and Nigeria accessions into two separate clusters, with accessions from Cameroun overlapping them. Principal coordinate analysis (PCO) indicated a closer relationship between accessions from Cameroun and Gabon. In general the Cameroun germplasm appears to be a bridge between the genetically isolated Nigeria and Gabon accessions. This overlap of Gabon and Nigerian accessions by the accessions from Cameroun may be an indication that Cameroun is the center of diversity of I. gabonensis and also the primary source of original materials grown in the other countries. More collection in Cameroun is necessary to ensure the optimum collection and preservation of the existing genetic diversity in I. gabonensis.Keywords: Irvingia gabonensis, Accession, amplified fragment length polymorphism, genetic diversit
Presentation and Preliminary Results of DROĂD Project: Development of a Distributed Optical Fibre Dosimeter
International audienceABSTRACT DROĂD project is intended to develop a distributed optical fibre dosimeter based on Radiation-Induced Attenua-tion (RIA). The RIA will be measured by a high resolution Optical Time Domain Reflectometry (OTDR) technique that allows to locate the irradiated fibre section. The first part of the project focuses on designing a high radiation sensitive fibre. As a preliminary work, the attenu-ation of several fibres with various compositions has been recorded in situ during and after irradiation. The experimental setup and RIA values are presented and discussed. Several dopants and their combinations have been identified as a good starting point to design a highly radiation sensitive fibre
Characterization of Erbium-Doped Nanoparticles in Transparent Glass Ceramic Optical Fibres
We report on using nanometric mass spectroscopy and molecular dynamics modelling to characterize the composition and structure of self-grown erbium-doped nanoparticles in transparent glass ceramic optical fibres fabricated by modified chemical vapour deposition without post-ceramming
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