This work examined the design, fabrication, and testing of a bio-mimetic MEMS earthworm crawler with external actuators. The micro-earthworm consisted of a passive mobile shuttle with two flexible diamond shaped segments; each segment was independently squeezed by a pair of stationary chevron-shaped thermal actuators. By applying a specific sequence of squeezes to the earthworm segments, the shuttle could be driven backwards or forwards. Unlike existing inchworm drives, which use separate clamping and thrusting motors, the earthworm motor applies only clamping forces and lateral thrust is produced by the shuttle’s compliant geometry. A study of existing crawler work was performed; to the author’s knowledge, this was the first micro-crawler to achieve both clamping force and lateral motion using the same actuators. The earthworm assembly was fabricated using the POLYMUMPs process, with planar dimensions of 400 µm wide by 800 µm long. The stationary earthworm motors operated within the range of 4-9 V, and 0-10 kHz; these motors provided a maximum shuttle range of motion of 350 µm (~half the size of the device), a maximum shuttle speed of 17,000 µm /s at 10 kHz, and a maximum DC shuttle force of 80 µN. The shuttle speed was found to vary linearly with both input voltage and input frequency; the shuttle force was found to vary linearly with actuator voltage. The tested design had higher force, range, and speed (per device footprint) than most other existing designs. Future work recommendations included the implementation of multiple motors and a closed loop control system to allow an indefinite range of motion, as well as the investigation of a two degree of freedom crawler. / THE DESIGN AND TESTING OF A BIO-INSPIRED HIGH PRECISION, HIGH SPEED, LONG RANGE PERISTALTIC MICRO-MOTOR

Thesis (Ph.D.) - University of Queensland, 2002. / Includes bibliography.

Orientadores: José Roberto Guimarães, Edson Aparecido Abdul Nour / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-25T08:51:38Z (GMT). No. of bitstreams: 1 Candello_FernandoPena_M.pdf: 1963368 bytes, checksum: 78504c5406b503757532a0a28430340c (MD5) Previous issue date: 2014 / Resumo: Os fármacos veterinários utilizados para aumentar a produtividade agropecuária podem atingir o solo, via excreção animal, e causar impactos sobre os ecossistemas aquáticos e terrestres. Nesse trabalho, implantou-se o recente ensaio padronizado pela ABNT de comportamento de fuga com minhocas Eisenia andrei (representantes da macrofauna terrestre) para avaliar o efeito subletal do antimicrobiano sulfadiazina (fármaco sintético da classe das sulfonamidas), utilizada de forma extensiva na produção animal. Dessa forma, desenvolveu-se metodologia alternativa de cultivo dessa espécie de minhoca conhecida como vermelha-da-califórnia a partir de restos vegetais domésticos, visando à obtenção de organismos viáveis para os testes. Validou-se o ensaio com uma substância de referência, obtendo-se uma CE50-48h de 819 mg H3BO3 kg-1 (intervalo a 95%: 628 a 1066 mg kg-1), caracterizando-o como uma ferramenta padronizada para avaliação ecotoxicológica rápida de solos contaminados. Também foram executados ensaios com a substância-teste sulfadiazina em solo artificial tropical, obtendo-se baixas respostas de fuga (máxima: 30%), afastando-se da curva concentração-resposta linear, mas permitindo uma discussão acerca dos efeitos assimétricos dos xenobióticos no ambiente / Abstract: Veterinary pharmaceuticals used to increase agricultural productivity can reach soil via animal excretions, and cause impacts on aquatic and terrestrial ecosystems. In this work, the recent standardized ABNT avoidance behavior test was implanted using earthworms Eisenia andrei (terrestrial macrofauna representatives) to assess the sublethal effects of antimicrobial sulfadiazine (a sulfonamide synthetic drug), extensively used in animal production. It was developed an alternative cultivation method of this red worms species made of household vegetable wastes, in order to obtain viable organisms for testing. The escape essay was validated with reference substance, resulting a EC50-48h of 819 mg H3BO3 kg-1 (95% confidence interval: 628-1066 mg kg-1), characterizing it as a standardized tool for rapid ecotoxicological screening of contaminated soil. Some essays were performed with the test-substance sulfadiazine in tropical artificial soil, resulting in low response avoidance (maximum 30 %), away from the linear concentration-response curve, but allowing a discussion on the xenobiotics asymmetric effects over the environment / Mestrado / Saneamento e Ambiente / Mestre em Engenharia Civil

Vermicomposting is an eco-friendly waste management strategy. Its successful performance necessitate that key functioning parameters like earthworm stocking density, nutrient enrichment be established for each target waste/waste mixture. One main target waste mixture in South Africa, and in the University of Fort Hare in particular is waste paper mixed with cow dung and rock phosphate (RP) for phosphorus (P) enrichment. This study was carried out to address the following specific objectives, to determine (i) the effect of Eisenia fetida stocking density on the bioconversion of cow dung waste paper mixtures enriched with rock phosphate, (ii) an optimum application rate of low grade South African Rock Phosphate and time required for efficient vermicomposting of cow dung-waste paper mixtures, and (iii) to determine if the phosphorus in RP is responsible for improved biodegradation during the vermicomposting of cow dung-waste paper mixtures. Results of this study revealed that bioconversion of cow dung waste paper mixtures enriched with RP was highly dependent on E. fetida stocking density and time. The stocking density of 12.5 g-worms kg-1 feedstock of the mixtures resulted in highest earthworm growth rate and humification of the waste mixture as reflected by a C: N ratio of < 12, polymerization index (PI) or humic acid/fulvic acid ratio of > 1.9, and a humification index of >13 for the cow dung waste paper mixtures. A germination test carried out also revealed that the resultant vermicompost had no inhibitory effect on the germination of tomato, carrot, and radish. Extractable P increased with stocking density up to 22.5 g-worm kg-1 feedstock, suggesting that for maximum P release from RP enriched wastes, a high stocking density should be considered. Informed by an earlier study which demonstrated that RP improved vermidegration, a follow up study was done to determine the optimum amount of rock phosphate necessary for efficient vermidegradation of cow dung waste paper mixtures while ensuring a phosphorus rich vermicompost. The results showed that addition of RP at rates ≤ 1% P as RP efficiently enhanced the bioconversion of cow dung waste paper mixtures as reflected by low C: N ratio, high polymerization index (PI), HI and HR used as maturity indicators for matured compost. Final vermicompost products obtained at minimum amounts of RP application rates resulted highly humified vermicompost with finer morphological structure, with no inhibitory effect on the germination of tomato, carrot, and radish similar to the ones obtained at higher RP rates. The findings suggest that 1%P as RP application rate is optimum for efficient vermidegradation of cow dung waste paper mixtures. Since P or Ca happen to be the most prevalent elements in most rock phosphate used for compost enrichment, a study was carried out to determine if P or Ca in RP is predominantly responsible for the improved biodegradation of cow-dung waste paper mixture observed during vermicomposting. Phosphorus sources in form of triple superphosphate (TSP), phosphoric acid (PHA) and Ca in form of calcium chloride (CaCl2) salt were compared with rock phosphate. The results from the study indicated that TSP, a water soluble P source, resulted in greater and faster degradation of the waste mixtures than RP while the Ca source had the least effect. With TSP incorporation the compost maturity C: N ratio of 12 was reached within 28 days while RP, PHA and CaCl2 needed 42, 56 and more than 56 days, respectively. The results indicated that P was largely responsible for the enhanced bioconversion of the waste mixtures. This appeared linked to the effect of P to stimulate microbial growth as reflected by higher microbial biomass carbon levels where water soluble P sources were applied. The C: N ratios of the final vermicomposts at day 56 were 10, 11.5, 13, 14, and 23 for TSP, RP,PHA, Control (No P added) and CaCl2 treatments, respectively. Although TSP gave superior superior performance, RP may still be the preferred additive in the vermicomposting of cow dung waste paper mixtures as it is cheaper and produces mature compost in a shorter period of 8 weeks. Generally, the results of this study have shown that the vemidegradation of cow dung waste paper mixtures can be optimized through adoption of an E. fetida stocking density of 12.5g- worm kg-1 and an RP incorporation rate of 1% P as RP. However, higher rates of RPincorporation may be adopted where final vermicomposts with higher P fertilizer value are desired. Phosphorus appears to be the RP constituent responsible for its ability to enhance the vermidegradation of cow dung waste paper mixtures. Future studies should explore the effectiveness of other P-bearing minerals for their effectiveness in enhancing vemidegradation.

No description available.

This research defines the morphological characteristics of the immune cells, coelomocytes, of the earthworm, Lumbricus terrestris. Such a definition of coelomocyte morphology can be correlated with immune function which will be of value in the development of a nonmammalian surrogate system to assess the immunotoxic potential of a terrestrial xenobiotics. Earthworms exposed to artificial soil dilutions of two complex xenobiotic mixtures, refuse derived fuel fly ash and a Superfund sire soil demonstrated an enhanced ability to produce hemolytic factors.

No description available.

In addition to their potential value for in situ bioremediation, the earthworm as a laboratory model may offer insight into mechanisms of xenobiotic toxicity. Using the filter paper contact toxicity test, the LD50s of a series of salicylates and phenolics were determined. The rank order in toxicity of these chemicals was compared with mammalian (rat, oral dosing) LD50s and found to be similar. To determine if protein secretion from chemical stress would be a more sensitive toxicity marker for the above xenobiotics, worms were exposed to either sodium salicylate or acetaminophen at a no effect level (NOAEL) and at the LD100 through filter paper contact. The ability of L. terrestris to metabolize drugs was investigated by using worm homogenate to treat various drugs in both encapsulated and free enzyme forms.

Urban forests perform essential ecological functions, and their performance is dependent on soil quality, which is often degraded by human activity. Because earthworms play a key role in soil health, augmenting earthworm populations in urban soils may improve tree performance. However, we know very little about earthworm ecology in highly urbanized soils. The objectives of our study were: (1) to assess earthworm demographics across a range of urban land uses and (2) to evaluate earthworm augmentation techniques for rehabilitating disturbed soils and improving tree growth. 1. We conducted an observational study across three landuse types to assess earthworm abundance and diversity as well as associated soil properties. Earthworm abundance and biomass in were affected by land use type, disturbance time frame, and seasonality. Earthworm abundance and biomass were affected by a suite of complex soil and temporal variables, and soil temperature and moisture seemed to be the most influential properties. 2. We conducted an earthworm inoculation experiment on a compacted cut-fill field soil with a very low existing earthworm population. In 2008, three soil treatments (control, compost, and compost + earthworm) were applied to 2 m2 plots into which two common urban tree species with contrasting soil tolerances were planted (Acer rubrum and Cornus florida). We measured soil physical and chemical properties along with earthworm survival and soil respiration. Earthworm inoculation did not succeed in improving bulk density or increasing soil organic matter, yet it was successful in increasing soil CEC, Fe, and Mn relative to compost only effects. / Master of Science

The raising earthworms by cassava waste is a useful solution to reduce environmental pollution caused by cassava starch processing. In this study, cassava waste (including cassava peel, cassava pieces and soil) was used as a food source for raising African Nightcrawler (Eudrilus eugeniae) with three experiments: E1, earthworms were raised in crushed cassava waste right after being discharged; E2, earthworms raised in crushed cassava waste that had been incubated with organic matter after decomposing microbiological preparation for the previous two weeks; E3, earthworms were raised in crushed cassava waste that had self-decomposed naturally for the previous two weeks. The cassava waste was decomposed naturally for 4 weeks for control. The results showed that the content of organic matter, humic acid and total nitrogen in organic cassava humus, obtaining from experiments, increased compared to the control; the total organic matter content reached from 10.4%-15.7%, higher than the control (8.2%) from 1.27-1.92 times, humic acid content reached 0.6 - 0.8% and total nitrogen reached 0.3%. Experiment 3 had the highest quality of humus (organic matter content 15.7%, total nitrogen 0.3%, humic acid 0.7% and fulvic acid 0.5%). The experiment 3 also had the highest earthworm biomass (3.6kg), increasing 30.5% compared to experiment 1 and 19.4% comparing to experiment 2. Therefore, experiment 3 was proposed for application in treatment of cassava waste at larger scale. The organic humus obtaining from raising earthworms by cassava waste can be used as raw material for vermicompost production. The earthworm biomass can be used as protein-rich food for domestic animals (such as chicken, tortoise, eel, fish, etc) or used as nutritious fertilizer. / Nuôi giun bằng phế liệu sắn là giải pháp hữu ích nhằm giảm thiểu ô nhiễm môi trường do chế biến tinh bột sắn gây ra. Trong nghiên cứu này, bã thải sắn (bao gồm vỏ, đầu mẩu sắn và bùn đất) được sử dụng làm nguồn thức ăn giun đất Châu Phi (African Nightcrawler (Eudrilus eugeniae) với các thí nghiệm như sau: Thí nghiệm 1: Giun quế được nuôi trong bã thải sắn nghiền ngay sau khi được loại bỏ; Thí nghiệm 2: giun đất được nuôi trong bã thải sắn nghiền đã được ủ với chế phẩm vi sinh phân hủy chất hữu cơ trong hai tuần trước đó; Thí nghiệm 3: Giun đất được nuôi trong bã thải sắn nghiền được để tự phân hủy tự nhiên trong hai tuần trước đó. Đối chứng là bã thải sắn để phân hủy tự nhiên trong 4 tuần. Bên cạnh đó, bã thải sắn nghiền còn được ủ bằng chế phẩm vi sinh phân hủy chất hữu cơ trong 4 tuần để cung cấp thêm số liệu so sánh giữa các thí nghiệm (Thí nghiệm 4). Các thí nghiệm được theo dõi trong 4 tuần. Kết quả cho thấy: Kết quả cho thấy: hàm lượng chất hữu cơ, axit humic và nitơ tổng trong mùn sắn hữu cơ thu được từ thí nghiệm đều tăng so với đối chứng: hàm lượng chất hữu cơ tổng số đạt từ 10,4% -15,7%, cao hơn đối chứng (8,2%) so với 1,27-1,92 lần, hàm lượng axit humic đạt 0,6 - 0,8% và nitơ tổng số đạt 0,3%. Trong đó, thí nghiệm 3 có chất lượng mùn cao nhất (hàm lượng chất hữu cơ 15,7%, đạm tổng số 0,3%, axit humic 0,7% và axit fulvic 0,5%). Thí nghiệm 3 cũng có sinh khối giun quế cao nhất (3,6kg), tăng 30,5% so với thí nghiệm 1 và 19,4% so với thí nghiệm 2. Do đó, thí nghiệm 3 đã được đề xuất ứng dụng để xử lý phế thải sắn ở quy mô lớn hơn. Chất mùn hữu cơ thu được từ việc nuôi trùn quế bằng phế thải sắn có thể được sử dụng làm nguyên liệu để sản xuất phân trùn quế. Sinh khối trùn quế có thể dùng làm thức ăn giàu đạm cho vật nuôi (như gà, ba ba, lươn, cá ...) hoặc làm phân bón dinh dưỡng.