Abstract: Growing industrial interest in products from renewable alternative feedstocks has resulted in the creation of more industry-led federal research and development programs. The basis of this interest is introduced, followed by an overview of the various federal programs that support basic through applied research relevant to chemical products from renewable resources, and evidence of the increased coordination efforts between programs. The majority of the paper outlines a new program within the U.S. Department of Energy, the Alternative Feedstocks Program, which specifically targets chemicals from renewables which have the potential to become part of the next generation of high-volume chemical feedstocks for the manufacturing industries. The first product of the program, an iterative process technology decision analysis tool, is broadly presented using the first process development project: succinic acid from fermentable sugars. 相似文献
A comparative analysis of the conservation value of nine Hong Kong mangals spread across Hong Kong has been undertaken. The analysis is based on both biological and socio-economic attributes. Biological attributes used in the analysis include plant species richness, benthic and arboreal gastropod species richness, occurrence of rare species within each site, and site representativeness. A review of the past and present development and development plans around and within each site has been undertaken to assess the comparative degree of hazard to each mangal. The drastic decline of mangal habitats throughout Hong Kong highlights the need for conservation of what remains today. Priorities and strategies for conservation of these nine mangals are discussed with particular emphasis on the preservation of biodiversity and the management of these habitats as education and research sites.Department of Applied Biology & Chemical Technology, Hong Kong Polytechnic 相似文献
We examined the survival of a host Escherichia coli K-12 bacterium containing two transferable plasmids (pLM2, pSL222-4) and one poorly mobilizable plasmid (pBR322), and the transfer of these three plasmids to endogenous bacteria in the human intestinal tract. The survival of this plasmid-carrying host organism in four human volunteers was 3.5 to 6 days at recovery rates of 10?1 to 10?4. This finding was similar to our previous survival data on the same organism bearing a single plasmid. The K-12 strain appeared to be under a strong selective disadvantage in the human gut, since, even when bearing a tetracycline-resistant plasmid, its titer did not increase despite the administration of tetracycline. Studies of transferability showed that, while the transfer-depressed incFII plasmid pSL222-4 transferred at a frequency of 10?1 in culture, its transfer in the human gut was much less frequent. The number of new recipients per donor cell ingested was about 10?5, which included new recipients arising by multiplication. The recovery of pSL222-4 transcipients was enhanced by the administration of tetracycline on day 6. Neither the transfer-repressed, broad host range incP plasmid pLM2, nor the plasmid pBR322, could be detected in any endogenous host bacteria. Using the transfer and mobilization frequencies obtained in culture and the number of new recipients of pSL222-4 in the intestinal tract, we estimated that any in vivo mobilization of pBR322 to a new recipient could not occur at a frequency higher than 10?12. 相似文献
Summary To estimate worker exposures to, and environmental contamination from, test chemicals and organic solvents used in an in vitro
assay to assess the carcinogenic potential of chemicals, sodium fluorescein, a noncarcinogenic fluorescent material, was dissolved
in tissue culture medium used to maintain early passage hamster embryo cells. Personal and environmental samples were taken
over a 14-d period. The assay was performed according to standard procedures in a ventilated glove box or laminar flow safety
cabinet. Considerably more than 99% of the chemical contamination found was recovered from the interiors of the glove box
and hood and from disposable equipment. Contamination outside the containment units (less than 1 μg) resulted from intralaboratory
transport of chemicals, treated cultures, and contaminated equipment. We conclude that the standard operating practices and
procedures provided adequate safeguards for personnel and the environment.
Research sponsored by the National Cancer Institute under Contract N01-CO-75380, with Litton Bionetics, Inc. 相似文献
New thiophene (2–13) and thienopyrimidine (15–27) derivatives have been synthesized. Twenty three compounds were screened against five cell lines namely; hepatocellular carcinoma (liver) HepG-2, epidermoid carcinoma (larynx) Hep-2, mammary gland (breast) MCF-7, human prostate cancer PC-3 and epithelioid cervix carcinoma HeLa. The results revealed that compounds 15,16,17,24 and 25 showed the highest antitumor activity against all tested cell lines compared to Doxorubicin. In order to explain the expected mode of action of the observed anticancer activity, compounds 15,16,17,24 and 25 were selected to screen their DNA binding affinity and enzyme inhibitory activity against DNA polymerase, thymidylate synthase and tyrosine kinase. The results revealed that the tested compounds showed good DNA binding affinity as well as good inhibitory activity against the three enzymes which might explain the observed anticancer activity of the target compounds. 相似文献
1. 1. The objective of this paper is to investigate the indoor environment from the viewpoint of interaction between physical environment and the human responses. The field survey has been conducted over 1 year.
2. 2. A continuous measurement has been carried out for 1 week and distribution of variables have been measured for 1 day.
3. 3. The attitude of workers was investigated by a questionnaire.
4. 4. As the result, average luminance represented more than 1000 lx in the new building, in contrast with less tha 300 lx in the existing building.
5. 5. There was a significant difference of the occupants' response to the light environment between the two buildings.
6. 6. Measured thermal conditions are on the edge of the ASHRAE comfort envelope in summer, and in the neighborhood of the lower dry limit of the envelope in spring.
7. 7. The occupants' evaluations were remarkably changed before and after the moving. The office environment is better than that of the factory.
The success in biomedical sciences such as genomics and proteomics is not paralleled in the medical product development methods. The consequence of this is a lack of translation into improved drug safety and efficacy. Therefore the US Food and Drug Administration (FDA) introduced the Critical Path Initiative in 2004 to modernize drug development and safety pharmacology. Bone is that largest tissue by weight, and is continuously remodelled. Changes in bone turnover lead to complications such as osteoporosis and fracture, that is associated with an increased mortality. Recent findings have identified bone as a possible endocrine organ and the availability of valid biochemical bone markers suggests that assessing bone turnover should also play an important role in general safety pharmacology. 相似文献
Many insects possess adhesive organs that can produce extreme attachment forces of more than 100 times body weight but they can rapidly release adhesion to allow locomotion. During walking, weaver ants (Oecophylla smaragdina) use only a fraction of their maximally available contact area, even upside-down on a smooth surface. To test whether the reduced contact area makes the ants more susceptible to sudden and unexpected detachment forces, for example, by rain or wind gusts, we investigated the reaction of untethered ants to rapid horizontal displacements of the substrate. High-speed video recordings revealed that the pad''s contact area could more than double within the first millisecond after the perturbation. This contact area expansion is much faster than any neuromuscular reflex and therefore represents a passive ‘preflex’, resulting from the mechanical properties and geometrical arrangement of the (pre-)tarsus. This preflex reaction protects ants effectively against unexpected detachment, and allows them to use less contact area during locomotion. Contact area expanded most strongly when the substrate displacement generated a pull along the axis of the tarsus, showing that the ants'' preflex is direction-dependent. The preflex may be based on the ability of Hymenopteran adhesive pads to unfold when pulled towards the body. We tested Indian stick insects (Carausius morosus), which have smooth pads that lack this motility. Similar to the ants, they showed a rapid and direction-dependent expansion of the contact area mainly in the lateral direction. We propose that the preflex reaction in stick insects is based on the reorientation of internal cuticle fibrils in a constant-volume system, whereas the ants'' pad cuticle is probably not a hydrostat, and pad extension is achieved by the arcus, an endoscelerite of the arolium. 相似文献