Assessment of Chemical Inhibitor Addition to Improve the Gas Production from Biowaste

The coexistence of sulphate-reducing bacteria and methanogenic archaea in the reactors during the anaerobic digestion from sulphate-containing waste could favor the accumulation of sulfide on the biogas, and therefore reduce its quality. In this study, the effect of sulphate-reducing bacteria inhibitor (MoO−2 4 ) addition in a two phase system from sulphate-containing municipal solid waste to improve the quality of the biogas has been investigated. The results showed that although SRB and sulphide production decreased, the use of inhibitor was not effective to improve the anaerobic digestion in a two phase system from sulphate-containing waste, since a significant decrease on biogas and organic matter removal were observed. Before MoO−2 4 addition the average values of volatile solid were around 12 g/kg, after 5 days of inhibitor use, those values did exceed to 28 g/kg. Molybdate caused acidification in the reactor and it was according to decrease in the pH values. In relation to microbial consortia, the effect of inhibitor was a decrease in Bacteria (44%; 60% in sulphate-reducing bacteria) and Archaea (38%) population

Real-time process plant fault diagnosis

Operators can become confused while diagnosing faults in process plant while in operation. This may prevent remedial actions being taken before hazardous consequences can occur. The work in this thesis proposes a method to aid plant operators in systematically finding the causes of any fault in the process plant. A computer aided fault diagnosis package has been developed for use on the widely available IBM PC compatible microcomputer. The program displays a coloured diagram of a fault tree on the VDU of the microcomputer, so that the operator can see the link between the fault and its causes. The consequences of the fault and the causes of the fault are also shown to provide a warning of what may happen if the fault is not remedied. The cause and effect data needed by the package are obtained from a hazard and operability (HAZOP) study on the process plant. The result of the HAZOP study is recorded as cause and symptom equations which are translated into a data structure and stored in the computer as a file for the package to access. Probability values are assigned to the events that constitute the basic causes of any deviation. From these probability values, the a priori probabilities of occurrence of other events are evaluated. A top-down recursive algorithm, called TDRA, for evaluating the probability of every event in a fault tree has been developed. From the a priori probabilities, the conditional probabilities of the causes of the fault are then evaluated using Bayes' conditional probability theorem. The posteriori probability values could then be used by the operators to check in an orderly manner the cause of the fault. The package has been tested using the results of a HAZOP study on a pilot distillation plant. The results from the test show how easy it is to trace the chain of events that leads to the primary cause of a fault. This method could be applied in a real process environment

Evaluating Morphological Computation in Muscle and DC-motor Driven Models of Human Hopping

In the context of embodied artificial intelligence, morphological computation refers to processes which are conducted by the body (and environment) that otherwise would have to be performed by the brain. Exploiting environmental and morphological properties is an important feature of embodied systems. The main reason is that it allows to significantly reduce the controller complexity. An important aspect of morphological computation is that it cannot be assigned to an embodied system per se, but that it is, as we show, behavior- and state-dependent. In this work, we evaluate two different measures of morphological computation that can be applied in robotic systems and in computer simulations of biological movement. As an example, these measures were evaluated on muscle and DC-motor driven hopping models. We show that a state-dependent analysis of the hopping behaviors provides additional insights that cannot be gained from the averaged measures alone. This work includes algorithms and computer code for the measures.Comment: 10 pages, 4 figures, 1 table, 5 algorithm

Morphological and molecular characterization of a new species of Isospora Schneider, 1881 (Apicomplexa: Eimeriidae) from the western wattlebird Anthochaera lunulata Gould in Western Australia

A new coccidian species, Isospora lunulatae n. sp., from the western wattlebird Anthochaera lunulata Gould in Western Australia is described and characterised molecularly. Microscopic analysis of a faecal sample identified subspheroidal oöcysts measuring 27–34 × 26–31 (30.6 × 29.4) μm (n = 20), with a length/width (L/W) ratio of 1.0–1.1 (1.0). Oöcysts have a bi-layered wall, 0.9–1.2 (1.0) μm thick; the outer layer is smooth, representing c.2/3 of total thickness. Micropyle and oöcyst residuum are both absent, but a polar granule is present. Sporocysts are ovoidal, 17–19 × 10–12 (18.3 × 10.7) μm, with a L/W ratio of 1.6–1.8 (1.7) and occupying about 21% of the area (each one) within the oöcyst. Stieda body is flattened to rounded, measuring on average 0.9 × 1.8 μm; sub-Stieda body is rounded to rectangular, measuring on average 1.5 × 2.6 μm; para-Stieda body is absent. Sporocyst residuum has an irregular shape consisting of numerous granules and appears membrane-bound. Sporozoites are vermiform 12.8 × 3.0 μm on average, with prominent striations at the more pointed end and two refractile bodies below striations. Segments of three gene loci (18S rRNA, 28S rRNA and cox1) were sequenced and I. lunulatae n. sp. exhibited 99.6% genetic similarity to Isospora phylidonyrisae Yang, Brice, Berto & Ryan, 2021 at the 18S rRNA gene locus, 99.8% genetic similarity to Isospora anthochaerae Yang, Brice & Ryan, 2014 and shared a 98.1% genetic similarity with Isospora manorinae Yang, Brice, Jian & Ryan, 2016 at the cox1 gene locus. Morphological and molecular data support the distinct species status of the new species

Cleaning of Floating Photovoltaic Systems: A Critical Review on Approaches from Technical and Economic Perspectives

There are some environmental factors, such as ambient temperature, dust, etc., which cause a reduction in the efficiency of Photovoltaic (PV) systems. Installation of PV panels on the water surface, commonly known as Floating Photovoltaic (FPV) systems, is one solution to employ PV panels in a cooler environment, achieve higher efficiency, and reduce water evaporation. FPV systems open up new opportunities for scaling up solar generating capacity, especially in countries with high population density and valuable lands, as well as countries with high evaporation rates and water resources deficiency. Since the FPV system is an almost new concept, its cleaning techniques have not been comprehensively studied. While FPV systems are located on the surface of water resources and reservoirs, the water quality can limit the application of different cleaning techniques. Therefore, this paper investigates different techniques of FPV systems cleaning and categorizes them into water-based and water-free approaches. In addition, their cleaning frequencies, as well as economic aspects, are presented and discussed to determine their merits and demerits for using them in FPV system

A Theory of Cheap Control in Embodied Systems

We present a framework for designing cheap control architectures for embodied agents. Our derivation is guided by the classical problem of universal approximation, whereby we explore the possibility of exploiting the agent's embodiment for a new and more efficient universal approximation of behaviors generated by sensorimotor control. This embodied universal approximation is compared with the classical non-embodied universal approximation. To exemplify our approach, we present a detailed quantitative case study for policy models defined in terms of conditional restricted Boltzmann machines. In contrast to non-embodied universal approximation, which requires an exponential number of parameters, in the embodied setting we are able to generate all possible behaviors with a drastically smaller model, thus obtaining cheap universal approximation. We test and corroborate the theory experimentally with a six-legged walking machine. The experiments show that the sufficient controller complexity predicted by our theory is tight, which means that the theory has direct practical implications. Keywords: cheap design, embodiment, sensorimotor loop, universal approximation, conditional restricted Boltzmann machineComment: 27 pages, 10 figure

3D printing and morphological characterisation of polymeric composite scaffolds

© 2020 Elsevier Ltd. All rights reserved. This manuscript is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International Licence http://creativecommons.org/licenses/by-nc-nd/4.0/.3D-printing is an efficient method of designing customised structures and producing synthetic bone grafts appropriate for bone implants. This research aimed to manufacture a new multi-functionalised 3D-printed poly(lactic acid)/carbonated hydroxyapatite (PLA/cHA) scaffolds with mass proportions of 100/0, 95/5 and 90/10 in a bid to verify their potential application in tissue regeneration. The filaments of these hybrid materials were obtained by extrusion technique and subsequently used to manufacture the 3D-printed scaffolds, using a fused deposition modelling (FDM) technique. The scaffolds were characterised based on their thermal properties, microstructure and geometry by differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and energy dispersive x-ray spectroscopy (EDS), respectively, in addition to determination of their apparent porosities. The degradation of the scaffolds and the liberation of degradation products were evaluated in in vitro for different days under simulated physiological conditions. New microanalyses of mechanical behaviour of the materials: tensile and compression stresses, density, frequency analysis and optimisation with DSC were performed. While, evaluation of the surface luminance structure and the profile structure of the nanostructured PLA composite materials was done by SEM, in 3D printed form. The filter profile of cross-sectional view of the specimen was extracted and evaluated with Firestone curve of the Gaussian filter; checking the roughness and waviness profile of the structure. It was observed that the thermal properties of the composites were not affected by the manufacturing process. The microstructural analysis showed the effective incorporation of the ceramic filler in the polymer matrix as well as an acceptable PLA/cHA interaction. The degradation tests showed the presence of calcium and phosphorus in the studied medium, confirming their liberation from the composites during the incubation periods.Peer reviewedFinal Accepted Versio

Eimeria spp. and Tyzzeria perniciosa Allen, 1936 (Apicomplexa: Eimeriidae) from a Pacific black duck, Anas superciliosa Gmelin (Aves: Anseriformes), in western Australia

Four species of the Eimeriidae, Eimeria anatis Scholtyseck, 1955, Eimeria aythyae Farr, 1965, Eimeria krylovi Svanbaev & Rakhmatullina, 1967 and Tyzzeria perniciosa Allen, 1936, were morphologically identified from oöcysts recovered from a Pacific black duck, Anas superciliosa Gmelin. Additionally, genotypic characterization of E. anatis is provided via sequencing of the mitochondrial cytochrome c oxidase subunit 1 (cox1) and the small subunit ribosomal RNA (18S) genes. The four species are redescribed, providing additional morphological details. The validity of genera and coccidian species parasitizing birds of the order Anseriformes such as Wenyonella Hoare, 1933 and some Tyzzeria spp. are discussed. Molecular phylogenetic analyses for the cox1 and 18S rRNA genes resulted in monophylies of Eimeria spp. from Anseriformes which included the sequences obtained from E. anatis oöcysts

Organoids and bioengineered intestinal models: Potential solutions to the Cryptosporidium culturing dilemma

Cryptosporidium is a major cause of severe diarrhea-related disease in children in developing countries, but currently no vaccine or effective treatment exists for those who are most at risk of serious illness. This is partly due to the lack of in vitro culturing methods that are able to support the entire Cryptosporidium life cycle, which has led to research in Cryptosporidium biology lagging behind other protozoan parasites. In vivo models such as gnotobiotic piglets are complex, and standard in vitro culturing methods in transformed cell lines, such as HCT-8 cells, have not been able to fully support fertilization occurring in vitro. Additionally, the Cryptosporidium life cycle has also been reported to occur in the absence of host cells. Recently developed bioengineered intestinal models, however, have shown more promising results and are able to reproduce a whole cycle of infectivity in one model system. This review evaluates the recent advances in Cryptosporidium culturing techniques and proposes future directions for research that may build upon these successes