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1.Purpose of the research We observed frequent application of chemical pesticides and herbicides at the pear orchards near our school. Our concerning questions are the influences of agricultural chemicals on soil ecosystem which may be slowly deteriorating. There are many other orchards where the farmers are practicing environmentally-friendly agriculture using organic fertilizers such as composed manure instead of sycnthetic fertilizers. The purpose of this research is to examine chemical and mocrobiological quality of the orchard soil. We report biological control of pear disease using antagonistic microorganisms and suggest improvement of soil quality as a result of nature friendly agricultural practice. 2.Procedures and Data Two orchards were selected: Conventional fertilizers and chemical pesticide application farm; Environmentally friendly farm using organic plant manure and biological control of disease. Several different aspects of soil micro-flora, indicator microorganisms, physiological characteristics of pear fruit, residues of synthetic chemicals in the soil, soil chemical properties were examined. We could observe that use of organic manure and biological control agents for disease control by indigenous microorganisms improved biological and chemical quality of the orchard soil. Results are summarized as follow: A. Microbial diversity could be observed in organic farming orchard soil. Among 42 fungal genus, 7 species of penicillium including P. decumns, 3 Alternaria species, 4 Fusarium species including Fusarium graminearum, 6 Aspergillus species including Aspergillus niger were identified. In case of bacteria, 59 samples were isolated and 17 genus including Cystophaga johsonae were identified. B. Beneficial indigenous bacteria having several biological functions were isolated: Enterobacter intermedium produces organic acid therefore this bacterium can solubilize insoluble phosphate. Several Pseudomonas species were isolated. These bacteria produce iron chelating compound under iron limited environments and can control plant disease. Interestingly, we could find indigenous biocontrol agent Hypocrea vinosa which can effectively control black star disease on pear surface. C. We have formulated ten different microbial-pesticides using several combinations of indigeous microorganisms such as Hypocrea vinosa, Trichoderma atroviride, Rhizopus microsporus etc. These microbial-pesticides could inhibit 100% of black star disease on pear surface which showed similar inhibition effect as commercial pesticides indicate that these microbial-pesticides may replace synthetic chemicals in the near furture. 3.Conclusions Our research demonstrates the eco-friendly organic farming system could improve soil eco-system of pear orchard, where no synthetic fertilizers and pesticides are applied. As a result of manure application, the soil chemical properties are more stable and microbiological flora was more diverse. Use of microbial and bio-pesticide resulted in strong inhibition of black-star disease incidence on pear surface. We suggest that eco-friendly farming systems are needed to diminish environmental pollution in soil and water caused by frequent and abundant use of agricultural chemicals.

Previously, I studied the acute effects of a common broadleaf herbicide, Killex (by Montsano) and a pesticide, Spidercide (by Wilson), on cytoplasmic streaming in detached leaves from the pond weed, Elodea canadensis. I found that Killex, active ingredient 2-4D, an auxin analog, applied at the recommended dose decreased the rate of cytoplasmic streaming by 64% over a 20 minute observational period. The Spidercide, active ingredient d-trans allethrin, a Na+ channel activator, stopped cytoplasmic streaming after a 5 minute exposure and no recovery was observed during the 20 minute observational period.

The purpose of this experiment is to determine whether or not wood can be used as an alternative testing method for sunscreens and which species of wood are good for this objective. This will be accomplished by applying varying strengths, or SPFs, of sunscreens onto thin wood veneers. They will then be exposed using a weatherometer, in which real light and sun conditions will be simulated. Using a device called a Pulmac, the samples of wood will be pulled apart from the centre at zero span. Based on the consistency of the strengths, it can be determined how the wood reacts to the sunscreen and whether that species of wood is suitable as a testing medium. Trees are an important commodity which enrich the lives of many people, particularly those who live in British Columbia. They provide the means of living and recreation for numerous people, whether it is employment, business, housing, or camping. Since trees are a renewable resource, they are convenient and realistic to use for testing. There are two possible extensions to this project. If the active ingredients in sunscreens can be determined, then we may be able to use these elements to create a new type of stain for fences and other structures. This could make the necessity for painting less frequent, creating cheaper options for the homeowner. The second possible extension of this project is to use the results to as an initiative to reduce the amount of animal and human testing done by manufacturers. This is important, as animal testing not only causes unnecessary pain, but often the results are not very accurate. Overall, I determined that this method of testing sunscreens would work quite well, especially with the following species, listed in decreasing order. 1) Yellow Cedar 2) Yellow Poplar 3) Maple 4) Hemlock These results were based on how tightly grouped together the means of the strength values were for each species. The closer they were, the more consistent that type of wood and therefore the better they are for testing. Overall, I think this method of testing sunscreens would work quite well, particularly with the yellow cedar, maple, yellow poplar and hemlock, as they resulted in fairly consistent strength values. Generally, the sunscreens with a high SPF, or Sun Protection Factor, resulted in a lower strength loss than the sunscreen with SPF 15. In addition to proving that sunscreen is a good method for preventing UV rays from reaching the skin, this experiment has also confirmed that there are other methods of testing sunscreens, which can be researched further. Along with my main presentation I will be showing various graphs, statistics, and pictures. They will be supplemented by a booklet of “Commonly Asked Questions and Answers” and species descriptions for each type of wood.

In the last two decades, there has been increased interest in the utility of quantum scale semiconductors. These fluorescent single crystals can be as small as 1 nm in diameter, and their size and shape has been shown to be controlled by the duration, temperature, and ligand molecules used in their synthesis. Quantum dots, provide clear benefits over the organic dyes currently used for tracking biological processes. Yet, as the production of quantum dots is often very costly, the search continues for finding an industry-ready synthesis for a quantum scale semiconductor which would have high yield, optimal durability, high luminescence, and a broad absorbance range. Silicon, in particular, has been of great interest as it is the second most abundant element on the Earth’s crust and is generally a bioinert and electrochemically stable element. We report the synthesis of water-soluble, luminescent silicon nanoparticles with potential applications to bioimaging. Through a solution state top-down approach, the synthesis of hydrogen capped silicon nanoparticles was achieved in various organic solvents. The surface of the nanoparticles was capped with the functional organic molecules rendering the Si-QDs both air and water stable. Cell studies performed with our silicon nanoparticles and human monocytes show the direct applications these particles could have for tracking biological processes and the progression of cancer in the human body. In attempt to shift the luminescence of these particles, alterations of experimental methodology was also explored in the areas of reaction solvent and heating time. Through these changes, shape control of silicon nanoparticles was achieved in the form of silicon nanorods. The synthesis of this new shape of silicon at the quantum scale was confirmed by ultraviolet spectroscopy, photoluminescence, and transmission electron microscopy. The results of this study indicate that the use of silicon nanocrystals for biomedical applications is feasible.

To measure the air quality of the city of Prince George by using lichen as bio-indicators of pollution.

Smoothened (SMO) is a critical component of Hedgehog (HH) pathway that is essential for stem cell renewal and is dysregulated in many cancer types. SMO is a seven transmembrane domain protein with three intracellular loops. Primary structures of SMO intracellular loops are unique and very much conserved among the species, which is indicative of significant and unique roles in intermolecular or intramolecular interactions. The hypothesis was that synthetic analogs of SMO intracellular loops may function as HH pathway inhibitors. Derivatives of second intracellular loop were synthesized utilizing automated solid phase peptide synthesis based on Fmoc chemistry. Peptides were purified by HPLC and there anti-proliferative activity tested on melanoma cells by MTT assay. Targeted libraries of second loop derivatives of varying length helped to identify compounds that inhibited the growth of melanoma cells in vitro with IC50 in nanomolar range. The most potent of antagonists obtained is the palmitoyl derivative of the Nterminal half of the loop, and is 12 residues long. Lipidation proved to be critical for the activity. Remarkably, retro-inverso versions of the peptide, in which all amino acids are in D-configuration, are even more potent and have IC50 in subnanomolar range. Circular dichroism studies proved that the peptides are folded both in aqueous solutions and in the presence of lipids mimicking the membrane environment. They also suggested that retroinverso analogs have a different fold, which may contribute to higher activity. The new compounds are promising drug candidates and present convenient tools for solving the\r mechanisms of hedgehog signaling.

Background:\r Delivery of anticancer drugs in vivo can be achieved by using targetspecific\r drug carriers of various types – e.g. microspheres and liposomes –\r which can be applied intravenously, or subcutaneously via a hypodermal\r patch, etc. as appropriate to the type of drug carrier employed. Recently,\r interest has surged in the usage of amphiphilic polymeric micelles for this\r purpose, as they prove superior to other drug carriers in many ways. They\r have highly-hydrated hydrophilic shells, and hydrophobic cores wherein\r hydrophobic anticancer drugs such as adriamycin can be encapsulated\r during transport in the blood. Their main advantages include their\r smallness of size – enabling them to elude capture by the\r reticuloendothelial system (RES) – their stability in the bloodstream as\r shown in their low critical micelle concentration (CMC) values, their\r passive targeting of tumour sites via the enhanced permeability and\r retention (EPR) effect, and their ability to integrate an active targeting\r mechanism, e.g. antibody-antigen recognition, pH-sensitivity, etc.

The Bay Mau Lake inside the Thong Nhat Park in Hanoi is the second largest lake in\r Hanoi. The lake serves not just as an equitable tank for the rainwater, as a reservoir for\r intake of wastewater, as a wastewater treatment pond, but also as a recreation area for\r Hanoi people and visitors from other provinces. The Bay Mau Lake is polluted at\r alarming level.\r The author has carried out a study on the water pollution level and the sources of\r pollution. The study revealed that the lake polluted mainly by domestic wastewater\r discharging from living quarters with total about 800,000 inhabitants. The author\r demonstrated different measures to reduce the pollution level in the lake such as raising\r environmental awareness for the public, a simple, reasonable cheap measure, which can\r be both realistic and effective. Besides, the author proposed to use bio-treatment of the\r water discharging into the Bay Mau Lake, building of a pumping station, fish farming...\r The clay-paper fibre mixture is used for the biological treatment of wastewater at the\r inlets. The advantage of this method is that it is a simple, cheap and realistic solution.\r Treatment of the water using clay and paper fibre mixture for filtration and plantation of\r aquatic plants as lotus and water lily together will provide oxygen for the aquatic\r environment of the lake. As results of the study, it is recommended to use both methods,\r namely raising environmental awareness for the public and biotreatement method using\r clay and paper fibre, to improve water quality of the lake.

Many biological processes in the human body take place in intracellular environments under crowded conditions. This means that such cellular activities occur in the presence of inert macromolecules. These macromolecules are thought to have large effects on reaction rates and equilibria. However, under conventional conditions, these same processes are studied in vitro under uncrowded conditions in dilute buffers and therefore not reflective of physiological conditions. Hence, this project aims to study the effect of macromolecular crowding on antigen-antibody reactions in an attempt to mimic intracellular environments. It also aims to highlight the importance of introducing crowders as a factor of study in conventional in vitro experiments involving cellular reactions. The model reaction investigated involves human collagen type 1 on skin samples and specific antibodies against these antigens. Inert macromolecules of defined hydrodynamic radius and charge were added into the reaction media while quantitative tests are conducted to determine the effect of crowding on the rate and extent of reaction. The macromolecular crowders used were Dextran Sulphate, Ficol170, Ficol1400 and Polyvinylpyrrolidone360. Results were than analysed with the Metamorph 7 imaging system to determine signal strength under crowded and non-crowded conditions. At high primary antibody dilutions, skin samples incubated with a primary antibody solution crowded with a combination of inert macromolecules showed improve signal strength. This could be because crowding tends to shift reaction equilibria such as to minimise the amount of excluded volume, leading to association of the antigen and its specific antibody. This is known as the excluded volume effect. In addition, crowding the primary antibody solution helped increase the rate of reaction. The results also suggest that the addition of crowders may reduce the amount of antibodies needed per sample and decrease the necessary incubation time. Therefore, antigen-antibody reactions can be done more cost-effectively, However, the presence of charged macromolecules such as Dextran Sulphate has an inhibitory effect. Further work is also needed to establish whether macromolecular crowding enhances specificity and thereby reduce autoflourescence of the skin sample.