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991.
Seasonal effects of 19 plant species on COD removal in subsurface treatment wetland microcosms 总被引:1,自引:0,他引:1
Carrie R. TaylorPaul B. Hook Otto R. Stein Cathy A. Zabinski 《Ecological Engineering》2011,37(5):703-710
Plants have many well-documented influences in treatment wetlands, but differences in individual species’ effects on year-round and seasonal performance are poorly understood. In this study, we evaluated plant effects on seasonal patterns of organic carbon removal (measured as COD) and sulfate concentration (used as an indicator of rootzone oxidation) in replicated, batch-loaded, greenhouse microcosms simulating subsurface treatment wetlands. Microcosms were planted with monocultures of 19 plant species or left unplanted as controls, dosed every 20 days with synthetic secondary wastewater, and operated over 20 months at temperatures from 4 to 24 °C. Study-long COD removal averaged 70% for controls and 70-97% for individual species. Most species enhanced COD removal significantly and the benefits of plants were greatest at 4-8 °C because COD removal decreased at low temperatures in controls but displayed limited seasonal variation in planted microcosms. Removal was significantly better at 24 °C than 4 °C with two species (Panicum virgatum and Leymus cinereus), significantly poorer with two species (Carex utriculata and Phalaris arundinacea), and did not differ with 15 species. Only one species showed a significant positive correlation between temperature and COD removal (Iris missouriensis, r = 0.67), while two species showed significant negative correlations (better when colder: Carex nebrascensis, r = −0.67; C. utriculata, r = −0.93). High COD removal throughout the study was strongly associated with high SO4 concentrations at low temperatures, suggesting that plant performance is related to rootzone oxidation and species’ abilities to promote aerobic over anaerobic microbial processes, particularly in winter. Results indicate that improved year-round and cold-season COD removal is common across diverse wetland plant species and novel species can be as good or better than those typically used. Better performing species were largely in the sedge and rush families (Cyperaceae and Juncaceae), while poorer performing species were largely in the grass family (Poaceae). 相似文献
992.
Sandra Strong Jennifer Federico Ron Banks Cathy Williams 《Journal of applied animal welfare science : JAAWS》2019,22(3):267-278
Companion-animal hoarding is a significant problem in the United States and internationally. Hoarding situations can incubate for years before a case is reported to law enforcement or animal control agencies. According to a survey by Gary Patronek, animal control agencies have estimated there are approximately 3000 reportable cases of animal hoarding annually in the United States. Animal hoarding cases vary in size from fewer than 20 animals to hundreds of animals. Every case of animal hoarding results in suboptimal animal welfare. Wake County, North Carolina, developed a proactive plan for addressing companion-animal hoarding that implemented a team approach to assist animals at risk, hold people accountable, address the mental health component of this problem, and create a more humane community. The plan involved animal control officers, crisis intervention counselors, law enforcement officers, veterinarians, veterinary technicians, and animal rescue partners. This intervention strategy was implemented in 2015, and cases were tracked to document animal outcomes. The conclusion of this experience is that a diverse team approach can best address the animal and human welfare challenges and the environmental concerns associated with animal hoarding. 相似文献
993.
Determination of Glutathione and ATP in Ganglia and Individual Neurons of Aplysia californica 总被引:1,自引:0,他引:1
The levels of two gamma-glutamyl cycle substrates, glutathione and ATP, were determined in single identified nerve cell bodies from the CNS of Aplysia californica. The glutathione content of single cells averaged 30 +/- 4.9 mumol/g protein. Glutathione levels were similar in identified cholinergic, serotonergic, and histaminergic cells, as well as in neurons whose transmitters are not yet identified. The abdominal rostral white cells, which are enriched in glycine, a component amino acid of glutathione, did not possess distinctively higher glutathione concentrations. The ATP content of single Aplysia nerve cell bodies averaged 15.0 +/- 1.5 mumol/g protein. Despite the vast chemical, anatomical, and functional heterogeneity between Aplysia central neurons, no cells were found that contained unusually high or low ATP levels. 相似文献
994.
Summary The effect of isoproterenol (IPR) on acinar cell mitoses was studied in regenerating submandibular glands of the rat following partial extirpation. In controls, mitoses of acinar cells were markedly higher on the cut surface (reactive zone) than in the remainder of the gland through 10 ds post-operation. In experimental animals by 5 ds, a burst of mitoses of acinar cells was seen in all areas of the gland except the reactive zone. In the reactive zone, IPR appears to suppress or inhibit the induced mitoses seen in controls.This study was supported by NIDR Grant # DE 05072-02 相似文献
995.
Natalia E. Schlabritz-Loutsevitch Adrian M. Whatmore Christine R. Quance Mark S. Koylass L. Bill Cummins Edward J. Dick Jr Cathy L. Snider David Cappelli Jeffrey L. Ebersole Peter W. Nathanielsz & Gene B. Hubbard 《Journal of medical primatology》2009,38(1):70-73
Background Brucellosis is veterinary and human health problem.
Methods A 13-year-old wild caught multiparous and an 8-year-old colony-born nulliparous baboon had stillbirths in the second trimester of pregnancy. Culture isolates from both postpartum uteruses were characterized using traditional biochemical analysis, PCR, and multilocus sequencing.
Results The isolates morphologically resembled Brucella although their phenotypic characteristics were not consistent with any currently described species. The isolates represent a novel lineage within the genus with unique alleles, not previously seen in surveys of greater than 300 isolates representing the known diversity of the genus, present at 5/9 loci examined.
Conclusions The described cases are to the best of our knowledge the first presentation of a naturally acquired Brucella infection in non-human primates associated with stillbirths from the same colony where Brucella seropositivity in the baboons was described 45 years ago. The organism appears to represent a previously undescribed Brucella species. 相似文献
Methods A 13-year-old wild caught multiparous and an 8-year-old colony-born nulliparous baboon had stillbirths in the second trimester of pregnancy. Culture isolates from both postpartum uteruses were characterized using traditional biochemical analysis, PCR, and multilocus sequencing.
Results The isolates morphologically resembled Brucella although their phenotypic characteristics were not consistent with any currently described species. The isolates represent a novel lineage within the genus with unique alleles, not previously seen in surveys of greater than 300 isolates representing the known diversity of the genus, present at 5/9 loci examined.
Conclusions The described cases are to the best of our knowledge the first presentation of a naturally acquired Brucella infection in non-human primates associated with stillbirths from the same colony where Brucella seropositivity in the baboons was described 45 years ago. The organism appears to represent a previously undescribed Brucella species. 相似文献
996.
Hydrobiologia - Scyphozoan jellyfish blooms display high interannual variability in terms of timing of appearance and size of the bloom. To understand the causes of this variability, the conditions... 相似文献
997.
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1000.
The effect on immunisation coverage of applying guiding principles to the management of primary health care services in a province in Papua New Guinea is described. These principles were: (a) Each health centre should have a defined geographical area of responsibility. (b) Each health centre should be responsible for a defined population. (c) Each health centre should have defined target groups for immunisation and child health clinic enrolment. (d) An accurate and meaningful reporting system is essential. (e) Each health centre should receive regular feedback on its achievements. Immunisation coverage in the province, as judged by the proportion of children under 1 year of age receiving their second dose of triple antigen, improved from 57-67% in 1980-2 to 89-94% in 1983-4.Immunisation is the most cost effective preventive activity undertaken in child health care. The application of these guiding principles would be relevant in the United Kingdom. 相似文献