8 resultados para toxicity of hair dyes
em Brock University, Canada
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Lock of hair from Charles Band – an envelope within another envelope containing Charles Band’s hair. This is from a haircut for Granny’s anniversary. The writing of the envelope says “Pussy’s hair” Nov. 21, 1922.
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Envelope containing a four leaf clover “for luck” and little Margaret’s hair (9 mos. old), Sept. 3, 1937.
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In light of the fact that literature on toxicity of heavy metals in non-acidified
freshwater systems is sparse, this project was initiated to conduct an environmental
assessment of Lake Gibson. Chemistry of soils from adjacent areas and vineyards in the
region provide a comparative background database. Water quality determinations were used
to identify and highlight areas of environmental concern within the Lake Gibson watershed.
A Shelby Corer was used to obtain 66 sediment cores from Lake Gibson. These were
sectioned according to lithology and color to yield 298 samples. A suite of 122 soil samples
was collected in the region and vicinity of Lake Gibson. All were tested for metals and
some for Total Petroleum Hydrocarbons (TPH). Evaluation of the results leads to the
following conclusions:
1. Metal concentrations ofAI, Cd, Cu, Cr, Pb, Ni, Fe and Zn in soils from the Niagara
Region are well below background limits set by the Ministry of the Environment
and Energy (MOEE) for provincial soils.
2. There is a spatial and depth difference for some of the metals within the various
soils. The Cr, Ni and Pb contents of soils vary throughout the region (p
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Sediment samples were taken from seven locations in the
WeIland River in December 1986 and April 1987. The DMSO extracts
of these sediment samples showed a significant (p
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The goal of this thesis was to study factors related to the development of Brassica juncea as a sustainable nematicide. Brassica juncea is characterized by the glycoside (glucosinolate) sinigrin. Various methods were developed for the determination of sinigrin in Brassica juncea tissue extracts. Sinigrin concentrations in plant tissues at various stages of growth were monitored. Sinigrin enzymatically breaks down into allylisothiocyanate (AITC). AITC is unstable in aqueous solution and degradation was studied in water and in soil. Finally, the toxicity of AITC against the root-lesion nematode (Pratylenchus penetrans) was determined. A method was developed to extract sinigrin from whole Brassica j uncea tissues. The optimal time of extraction wi th boiling phosphate buffer (0.7mM, pH=6.38) and methanol/water (70:30 v/v) solutions were both 25 minutes. Methanol/water extracted 13% greater amount of sinigrin than phosphate buffer solution. Degradation of sinigrin in boiling phosphate buffer solution (0.13%/minute) was similar to the loss of sinigrin during the extraction procedure. The loss of sinigrin from boiling methanol/water was estimated to be O.Ol%/minute. Brassica juncea extract clean up was accomplished by an ion-pair solid phase extraction (SPE) method. The recovery of sinigrin was 92.6% and coextractive impurities were not detected in the cleaned up extract. Several high performance liquid chromatography (HPLC) methods were developed for the determination of sinigrin. All the developed methods employed an isocratic mobile phase system wi th a low concentration of phosphate buffer solution, ammonium acetate solution or an ion-pair reagent solution. A step gradient system was also developed. The method involved preconditioning the analytical column with phosphate buffer solution and then switching the mobile phase to 100% water after sample injection.Sinigrin and benzyl-glucosinolate were both studied by HPLC particle beam negative chemical ionization mass spectrometry (HPLCPB- NCI-MS). Comparison of the mass spectra revealed the presence of fragments arising from the ~hioglucose moiety and glucosinolate side-chain. Variation in the slnlgrin concentration within Brassica juncea plants was studied (Domo and Cutlass cuItivars). The sinigrin concentration in the top three leaves was studied during growth of each cultivar. For Cutlass, the minimum (200~100~g/g) and maximum (1300~200~g/g) concentrations were observed at the third and seventh week after planting, respectively. For Domo, the minimum (190~70~g/g) and maximum (1100~400~g/g) concentrations were observed at the fourth and eighth week after planting, respectively. The highest sinigrin concentration was observed in flower tissues 2050±90~g/g and 2300±100~g/g for Cutlass and Domo cultivars, respectively. Physical properties of AITC were studied. The solubility of AITC in water was determined to be approximately 1290~g/ml at 24°C. An HPLC method was developed for the separation of degradation compounds from aqueous AITC sample solutions. Some of the degradation compounds identified have not been reported in the literature: allyl-thiourea, allyl-thiocyanate and diallyl-sulfide. In water, AITC degradation to' diallyl-thiourea was favored at basic pH (9.07) and degradation to diallyl-sulfide was favored at acidic pH (4 . 97). It wap necessary to amend the aqueous AITC sample solution with acetonitrile ?efore injection into the HPLC system. The acetonitrile amendment considerably improved AITC recovery and the reproducibility of the results. The half-life of aqueous AITC degradation at room temperature did not follow first-order kinetics. Beginning with a 1084~g/ml solution, the half-life was 633 hours. Wi th an ini tial AITC concentration of 335~g/ml the half-life was 865 hours. At 35°C the half-life AITC was 76+4 hours essentially independent of the iiisolution pH over the range of pH=4.97 to 9.07 (1000~g/ml). AITC degradation was also studied in soil at 35°C; after 24 hours approximately 75% of the initial AITC addition was unrecoverable by water extraction. The ECso of aqueous AITC against the root-lesion nematode (Pratylenchus penetrans) was determined to be approximately 20~g/ml at one hour exposure of the nematode to the test solution. The toxicological study was also performed with a myrosinase treated Brassica juncea extract. Myrosinase treatment of the Brassica juncea extract gave nearly quantitative conversion of sinigrin into AITC. The myrosinase treated extract was of the same efficacy as an aqueous AITC solution of equivalent concentration. The work of this thesis was focused upon understanding parameters relevant to the development of Brassica juncea as a sustainable nematicide. The broad range of experiments were undertaken in support of a research priority at Agriculture and Agri-Food Canada.
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A miniature portrait of Captain John Brock, 81st Regiment of Foot. There is an inscription on parchment attached to the reverse which reads "Major Gen. Sir Isaac Brock Lieut. Govenor of Upper Canada Fell at Queenston Heights on 13th Oct 1812" "The Hero of Canada". Above this inscription is a picture of an Indian on a battlement, holding what appears to be a tomahawk. Directly below this picture is a banner with the word "Canada" on it. The entire inscription is surrounded by a braided lock of hair which is enclosed in the case. This inscription contains a number of historical inaccuracies. The portrait also shows the buttons of the 81st Regiment. Sir Isaac Brock belonged to the 49th Regiment of Foot. It has thus been determined that the portrait is not of Isaac Brock but of his brother John.
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Artist’s rendering in colour of Isobel Price in an oval frame with a hook at the top and a section at the back which contains a lock of hair. This painting was done by Gerald Sinclair Hayward who was a renowned artist whose work was displayed at an exhibition in New York in 1899. He painted Theodore Roosevelt, William K. Vanderbilt and members of the ruling families of Britain, Germany and Russia. The frame is enclosed in a folding case lined with velvet and silk. The silk is quite worn. The outside of the case appears to be leather and has a stand for setting it upright. It closes with a metal latch. This is accompanied by a note by R. Band.
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The article focuses on the temperament of cattle depending on the position of hair whorl. The article was published in the journal Applied Animal Behaviour Science.