A Smart-bin prototype for in-house waste management

Thesis submitted in partial fulfillment of the requirements for the Degree of Master of Science in Information Technology (MSIT) at Strathmore UniversityA healthy environment is imperative to a healthy and happy community. Clean and well monitored environments are a key need in human habitable environments. In-House management and monitoring of waste is a key aspect in achieving this. The existing system of using waste monitoring personnel to regularly check and empty filled dustbins, the process has been prone to delays or neglect. Additionally, due to different frequency of usage of dustbins in different areas, routine checks which are based on time crevices is inefficient because a dustbin might get filled early and may need immediate attention or there might not be any need of a routine check for a long period of time. This makes present system resource expensive and ineffectual, as overflowing, stinking dustbins become more of a problem than a solution. This study presents a solution about the Smart-Bin Prototype for In-House Waste Management which integrates the idea of IoT with Wireless Sensor Networks. Arduino ATmega328P Microcontroller is used to interface the sensor system and the IoT hub. Dustbins in an area are embedded with low power and low cost smart ultrasonic and gas sensors that are connected to an IoT device, which acts as a central hub for all bins. The bins transmit their gas content and its fill-level status to the central hub which relays this data to a cloud platform. The cloud platform further pushes the data to the client app a GUI (Web or mobile) in which the current gas content and their state (filled or not) is displayed. The client app GUI can be used by the waste management personnel and data can be used to plan their routine check. This timely garbage monitoring would optimize resources, reduce cases of neglect and is easy to adopt

Dietary Impact on Antibiotic Resistance in Feedlot Manure

There is a growing public concern regarding antibiotic resistance and the use of antibiotics, including in livestock management. Understanding the ecology of antibiotic resistance among microbes, identifying resistance gene reservoirs, and implementing antibiotic resistance mitigation practices in livestock production are critical to protecting animal and human health while meeting increasing food demands. This research is one of several studies seeking to assess risk for livestock- to- human transfer of antibiotic resistance and to identify mechanisms for reducing that risk where possible. This study evaluated the impact of forage concentration and supplemental essential oil in beef cattle finishing diets on antibiotic resistance in freshly excreted and consolidated beef feedlot manure. Results indicate that antibiotic resistance in manure was not impacted by either of the two dietary treatments considered

Resistome and mobilome in surface runoff from manured soil as affected by setback distance

Land application of livestock manure introduces antibiotic resistance genes (ARGs) and mobile genetic elements (MGEs) into the soil environment. The objectives of this study were to examine the changes of resistome and mobilome in runoff and soil as a function of setback distance, i.e., the distance between manured soil and surface water, and to quantify the contributions of manure and background soil to the ARGs and MGEs in surface runoff. The resistome and mobilome in runoff and soil from a field-scale plot study were characterized using a high throughput quantitative polymerase chain reaction (HT-qPCR) array. It was estimated that a setback distance of ~40 m is required to reduce the total abundance of ARGs and MGEs in runoff from amended plots to that in control runoff. The resistome and mobilome of the soil in the setback region was not affected by manure-borne ARGs and MGEs. SourceTracker analyses revealed that background soil gradually became the predominant source of the ARGs and MGEs in runoff as setback distance increased. The results demonstrate how manure-borne ARGs and MGEs dissipated in agricultural runoff with increasing setback distance and had limited impacts on the resistome and mobilome of soil within the setback region

The role of the whitefly, Bemisia tabaci (Gennadius), and farmer practices in the spread of cassava brown streak ipomoviruses

Cassava brown streak disease (CBSD) is arguably the most dangerous current threat to cassava, which is Africa's most important food security crop. CBSD is caused by two RNA viruses: Cassava brown streak virus (CBSV) and Ugandan cassava brown streak virus (UCBSV). The roles of the whitefly Bemisia tabaci (Gennadius) and farmer practices in the spread of CBSD were investigated in a set of field and laboratory experiments. The virus was acquired and transmitted by B. tabaci within a short time (5–10 min each for virus acquisition and inoculation), and was retained for up to 48 hr. Highest virus transmission (60%) was achieved using 20–25 suspected viruliferous whiteflies per plant that were given acquisition and inoculation periods of 24 and 48 hr, respectively. Experiments mimicking the agronomic practices of cassava leaf picking or the use of contaminated tools for making cassava stem cuttings did not show the transmission of CBSV or UCBSV. Screenhouse and field experiments in Tanzania showed that the spread of CBSD next to spreader rows was high, and that the rate of spread decreased with increasing distance from the source of inoculum. The disease spread in the field up to a maximum of 17 m in a cropping season. These results collectively confirm that CBSV and UCBSV are transmitted by B. tabaci semipersistently, but for only short distances in the field. This implies that spread over longer distances is due to movements of infected stem cuttings used for planting material. These findings have important implications for developing appropriate management strategies for CBSD

Cassava brown streak disease: historical timeline, current knowledge and future prospects

Cassava is the second most important staple food crop in terms of per capita calories consumed in Africa and holds potential for climate change adaptation. Unfortunately, productivity in East and Central Africa is severely constrained by two viral diseases: cassava mosaic disease (CMD) and cassava brown streak disease (CBSD). CBSD was first reported in 1936 from northeast Tanzania. For approximately seventy years CBSD was restricted to coastal East Africa and so had a relatively low impact on food security compared to CMD. However, at the turn of the 21st century CBSD re-emerged further inland, in areas around Lake Victoria and it has since spread through many East and Central African countries, causing high yield losses and jeopardising the food security of subsistence farmers. This recent re-emergence has attracted intense scientific interest, with studies shedding light on CBSD viral epidemiology, sequence diversity, host interactions and potential sources of resistance within the cassava genome. This review reflects on 80 years of CBSD research history (1936 – 2016) with a timeline of key events. We provide insights into current CBSD knowledge, management efforts and future prospects for improved understanding needed to underpin effective control and mitigation of impacts on food security

Mitigation Strategies for Antimicrobial Resistance and Nutrients at Critical Control Points in Livestock Manure Management Systems

Livestock waste is regarded as an important source of antimicrobial resistance (AMR) and nutrients in the environment. This study focuses on developing novel manure management practices to mitigate the dissemination of AMR and nutrients at critical control points within the manure management system. The interventions tested include 1) lime amendment of pen floor surface materials in open feedlots for the reduction of AMR bacteria and genes, 2) heat treatment by conductive concrete slabs for the transformation of phosphorus P and nitrogen N in beef cattle manure stockpiles, and 3) setback distance, the distance between manured soil and surface water, as a means to reduce AMR genes in surface runoff following the land application of swine manure slurry. First, the application of lime to pen floor surface materials in open cattle feedlots significantly reduced the concentrations of AMR bacteria and genes. Stockpiles of lime-amended manure showed a significantly lower AMR bacteria and gene levels compared to stockpiled manure from control pens that received no lime. Beta diversity analysis showed that lime altered the microbial compositions in both pen floor surface materials and stockpiled manure. Second, bench-scale tests showed that the heat from a conductive concrete slab increased the fraction of the readily available NaHCO3-P in stockpiled manure. The concentrations of ammonium-N, total N, and total P were greater in runoff generated from the heat-treated manure after 10 days of stockpiling. Third, a high throughput quantitative polymerase chain reaction array was used to assess the resistome and mobilome in runoff and soil from field plots. The abundance of AMR genes and mobile genetic elements (MGEs) in runoff from manured plots decreased with increasing setback distance. A setback distance of ~40 m was estimated to reduce the total abundance of AMR genes and MGEs in runoff from manured plots to that of control runoff. SourceTracker analysis revealed that background soil gradually became the predominant source of AMR genes and MGEs in runoff as setback distance increased. These findings highlight potential mitigation strategies that stakeholders and farmers can use as best management practices to reduce AMR dissemination and nutrient loss from livestock manure

Development of banana bunchy top virus resistance in bananas: RNAi approach

Bunchy top, caused by banana bunchy top virus (BBTV), is the most important viral disease affecting banana worldwide, for which control is very difficult. In this thesis, a molecular approach was used to generate genetically modified banana plants, some of which were resistant to BBTV infection. Further, sources of natural resistance to BBTV were identified in a range of different banana cultivars which may be exploited in future control strategies. The results from this study provide a strong platform for the future development of BBTV-resistant banana plants

Vinyatsi Mjila (Grass on the road)

"Much grass on the road, take it all. When we walk we get tired of too much grass on the road." It is not easy to walk on dry grass as it is to slippery and the feet slip backwards and make you tired. The old player reflects a portion of country commonplace truth in this repetative little song. Humorous song with one string lute, Karigo