Toxicity of synthetic piperonyl compounds to leaf-cutting ants and their symbiotic fungus

The development of Leucoagaricus gongylophorus, the fungus cultured by the leaf-cutting ant Atta sexdens was inhibited in vitro by synthetic compounds containing the piperonyl group. In addition, worker ants that were fed daily on an artificial diet to which these compounds were added had a higher mortality rate than the controls. The inhibition of the fungal growth increased with the size of the carbon side chain ranging from C1 through C8 and decreasing thereafter. 1-(3,4-Methylenedioxybenzyloxy)octane (compound 5) was the most active compound and inhibited the fungal development by 80% at a concentration of 15 μg m1-1. With worker ants the toxic effects started with compound 5 and increased with the number of carbons in the side chain. Thus, for the same concentration (100 μg m1-1) the mortality rates observed after 8 days of diet ingestion were 82%, 66% and 42%, for 1-(3,4-methylenedioxybenzyloxy)decane, 1-(3,4-methylenedioxybenzyloxy)dodecane and compound 5, respectively, whereas with commercial piperonyl butoxide the mortality was 68%. The latter compound, which is known as a synergist insecticide, was as inhibitory to the symbiotic fungus as the synthetic compound 5. The possibility of controlling these insects in the future using compounds that can target simultaneously both organisms is discussed. © 2001 Society of Chemical Industry.

Extraction of oil from pressed palm oil (Elaes guineensis) fibers using supercritical CO2

Residual fibers from palm oil production are a good source of carotene, since they contain more than 5% of the original oil, with about 5000 ppm of carotenoids. As carotenoids are thermosensitive molecules, supercritical CO₂ can be used for oil recovery, because this technique employs low temperatures. In this work results of oil extraction experiments from pressed palm oil fibers are shown. Fibers were from AGROPALMA, an industry which is located in Tailândia (Pará, Brazil). Extractions were carried out at 200, 250 and 300 bar and at temperatures of 45 and 55oC. Oil was analyzed by UV/vis spectrophotometry for total carotene determination. Results showed a large increase in extraction rate from 200 to 250 bar and a small variation from 250 to 300 bar. The total amount of carotenes did not increase in the course of extraction at 300 bar, but it showed a large increase at 200 and at 250 bar. Free fatty acids are present in amounts larger than those found in commercial oils.

Effects of a synthetic gonadotrophin-releasing hormone agonist, leuprolide, on rut-associated events in male red deer

This study examined the effectiveness of leuprolide, a gonadotrophin-releasing hormone agonist, in suppressing rut-associated events in farmed male red deer. In mid-January (~6 weeks before the rut period in the southern hemisphere) adult red deer (Cervus elaphus scoticus) stags that had been allocated to three groups (n = 10 per group) received leuprolide, administered subcutaneously in a 90-day release formulation, at zero (control), low (22.5 mg) or high (45 mg) doses. Following treatment with leuprolide there was evidence of suppression of mean plasma luteinising hormone concentration that was significant (P < 0.05) at 9 weeks. Mean plasma testosterone concentration of all three groups rose following treatment, then declined prematurely in the low- and high-dose leuprolide-treated groups, so that it was significantly (P < 0.05) suppressed (0.66 ± 0.29 and 2.0 ± 0.88 ng mL–1, low and high dose respectively) in early April when the peak value (9.0 ± 1.94 ng mL–1) was recorded from control stags. A reduction in mean liveweight occurred in all three groups through February–April and this did not differ among treatments. However, a corresponding reduction in mean body condition score was greater in the control stags (P < 0.05). There was little effect of leuprolide treatment on aggressive behaviours, but it lowered roaring frequency in the latter period of the rut. The results indicate that this gonadotrophin-releasing hormone agonist has potential for application in the deer farming industry to suppress undesirable effects of the rut.

LYOCELL AND COTTON FIBERS AS REINFORCEMENTS FOR A THERMOSET POLYMER

Cellulose fibers obtained from the textile industry (lyocell) were investigated as a potential reinforcement for thermoset phenolic matrices, to improve their mechanical properties. Textile cotton fibers were also considered. The fibers were characterized in terms of their chemical composition and analyzed using TGA, SEM, and X-ray. The thermoset (non-reinforced) and composites (phenolic matrices reinforced with randomly dispersed fibers) were characterized using TG, DSC, SEM, DMTA, the Izod impact strength test, and water absorption capacity analysis. The composites that were reinforced with lyocell fibers exhibited impact strengths of nearly 240 Jm(-1), whereas those reinforced with cotton fibers exhibited impact strengths of up to 773 Jm(-1). In addition to the aspect ratio, the higher crystallinity of cotton fibers compared to lyocell likely plays a role in the impact strength of the composite reinforced by the fibers. The SEM images showed that the porosity of the textile fibers allowed good bulk diffusion of the phenolic resin, which, in turn, led to both good adhesion of fiber to matrix and fewer microvoids at the interface.

NON-CHROMATOGRAPHIC PURIFICATION OF SYNTHETIC BIO-OLIGOMERS

Synthetic oligonucleotides and peptides have found wide applications in industry and academic research labs. There are ~60 peptide drugs on the market and over 500 under development. The global annual sale of peptide drugs in 2010 was estimated to be $13 billion. There are three oligonucleotide-based drugs on market; among them, the FDA newly approved Kynamro was predicted to have a $100 million annual sale. The annual sale of oligonucleotides to academic labs was estimated to be $700 million. Both bio-oligomers are mostly synthesized on automated synthesizers using solid phase synthesis technology, in which nucleoside or amino acid monomers are added sequentially until the desired full-length sequence is reached. The additions cannot be complete, which generates truncated undesired failure sequences. For almost all applications, these impurities must be removed. The most widely used method is HPLC. However, the method is slow, expensive, labor-intensive, not amendable for automation, difficult to scale up, and unsuitable for high throughput purification. It needs large capital investment, and consumes large volumes of harmful solvents. The purification costs are estimated to be more than 50% of total production costs. Other methods for bio-oligomer purification also have drawbacks, and are less favored than HPLC for most applications. To overcome the problems of known biopolymer purification technologies, we have developed two non-chromatographic purification methods. They are (1) catching failure sequences by polymerization, and (2) catching full-length sequences by polymerization. In the first method, a polymerizable group is attached to the failure sequences of the bio-oligomers during automated synthesis; purification is achieved by simply polymerizing the failure sequences into an insoluble gel and extracting full-length sequences. In the second method, a polymerizable group is attached to the full-length sequences, which are then incorporated into a polymer; impurities are removed by washing, and pure product is cleaved from polymer. These methods do not need chromatography, and all drawbacks of HPLC no longer exist. Using them, purification is achieved by simple manipulations such as shaking and extraction. Therefore, they are suitable for large scale purification of oligonucleotide and peptide drugs, and also ideal for high throughput purification, which currently has a high demand for research projects involving total gene synthesis. The dissertation will present the details about the development of the techniques. Chapter 1 will make an introduction to oligodeoxynucleotides (ODNs), their synthesis and purification. Chapter 2 will describe the detailed studies of using the catching failure sequences by polymerization method to purify ODNs. Chapter 3 will describe the further optimization of the catching failure sequences by polymerization ODN purification technology to the level of practical use. Chapter 4 will present using the catching full-length sequence by polymerization method for ODN purification using acid-cleavable linker. Chapter 5 will make an introduction to peptides, their synthesis and purification. Chapter 6 will describe the studies using the catching full-length sequence by polymerization method for peptide purification.

La roca magica: Uses of natural zeolites in agriculture and industry

For nearly 200 years since their discovery in 1756, geologists considered the zeolite minerals to occur as fairly large crystals in the vugs and cavities of basalts and other traprock formations. Here, they were prized by mineral collectors, but their small abundance and polymineralic nature defied commercial exploitation. As the synthetic zeolite (molecular sieve) business began to take hold in the late 1950s, huge beds of zeolite-rich sediments, formed by the alteration of volcanic ash (glass) in lake and marine waters, were discovered in the western United States and elsewhere in the world. These beds were found to contain as much as 95% of a single zeolite; they were generally flat-lying and easily mined by surface methods. The properties of these low-cost natural materials mimicked those of many of their synthetic counterparts, and considerable effort has made since that time to develop applications for them based on their unique adsorption, cation-exchange, dehydration–rehydration, and catalytic properties. Natural zeolites (i.e., those found in volcanogenic sedimentary rocks) have been and are being used as building stone, as lightweight aggregate and pozzolans in cements and concretes, as filler in paper, in the take-up of Cs and Sr from nuclear waste and fallout, as soil amendments in agronomy and horticulture, in the removal of ammonia from municipal, industrial, and agricultural waste and drinking waters, as energy exchangers in solar refrigerators, as dietary supplements in animal diets, as consumer deodorizers, in pet litters, in taking up ammonia from animal manures, and as ammonia filters in kidney-dialysis units. From their use in construction during Roman times, to their role as hydroponic (zeoponic) substrate for growing plants on space missions, to their recent success in the healing of cuts and wounds, natural zeolites are now considered to be full-fledged mineral commodities, the use of which promise to expand even more in the future.

Commercial applications of speech interface technology: an industry at the threshold.

Speech interface technology, which includes automatic speech recognition, synthetic speech, and natural language processing, is beginning to have a significant impact on business and personal computer use. Today, powerful and inexpensive microprocessors and improved algorithms are driving commercial applications in computer command, consumer, data entry, speech-to-text, telephone, and voice verification. Robust speaker-independent recognition systems for command and navigation in personal computers are now available; telephone-based transaction and database inquiry systems using both speech synthesis and recognition are coming into use. Large-vocabulary speech interface systems for document creation and read-aloud proofing are expanding beyond niche markets. Today's applications represent a small preview of a rich future for speech interface technology that will eventually replace keyboards with microphones and loud-speakers to give easy accessibility to increasingly intelligent machines.

Assessment of best available technology economically achievable for synthetic rubber manufacturing wastewater /

Mode of access: Internet.

Pharmaceutical industry : hazardous waste generation, treatment, and disposal.

Final report (SW-508) describing work performed for the Federal Solid waste management program under Contract no. 68-01-2684.

Managing crises in defense industry : the PEPCON and Avtex cases /

Mode of access: Internet.

Asbestos standard for general industry.

"OSHA 3095."

High strength, high modulus fibers by pyrolysis of polymeric fibers

Mode of access: Internet.

Synthetic organic chemicals: United States production and sales.

Vols. issued as its TC publications.

Methanol as transportation fuel : hearings before the Subcommittee on Fossil and Synthetic Fuels and the Subcommittee on Energy Conservation and Power of the Committee on Energy and Commerce, House of Representatives, Ninety-eighth Congress, second session, on H.R. 4855 and H.R. 5075 ... April 4 and 25, 1984.

Mode of access: Internet.

Process inventory and pollution prevention overview for the citrus industry

Florida citrus represents approximately 70 percent of the industry production in the United States; therefore, any associated agricultural and industrial contamination is of concern and a focus of attention. The use of synthetic organic chemicals has become a farmer's necessity in order to supply consumers with high quality products, free of pest damage. However, industrial citrus wastes and chemical residual levels worry not only government agencies but also consumers since they indicate a serious habitat risk. This study assesses citrus industrial processes and the paths that chemical substances follow from the time the citrus seed is planted until consumers get a final product as either fresh fruit or processed product. The study is built on information from United States Environmental Protection Agency (US EPA) manuals, Dade County Environmental Resources Management (DERM) inspection records, United States Food and Drug Administration (US FDA) regulations, Florida standards, journal publications, and research reports. Pollution prevention (P2 or prevention-of-pollution) alternatives are identified; alternatives are proposed, evaluated, and included. Strategies are described and pollution prevention opportunities proposed to minimize citrus wastes generation, chemical residuals in products, their environmental impact and health risk aspects while maximizing product quality.