341 results on '"Bunce, R"'
Search Results
302. ChemInform Abstract: (.+-.)-3,4,4a,5,6,7-Hexahydro-4a-methyl-7,7-diphenyl-1(2H)- naphthalenone.
- Author
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BUNCE, R. A. and CHILDRESS, R. S.
- Published
- 1997
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303. ChemInform Abstract: A Ring Expansion Procedure Based on the Tandem Dealkoxycarbonylation- Michael Addition Reaction.
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BUNCE, R. A. and SCHILLING, C. L. III.
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- 1995
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304. ChemInform Abstract: Functionalized Carbocycles by Tandem Dealkoxycarbonylation-Michael Addition Reactions.
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BUNCE, R. A., DOWDY, E. D., JONES, P. B., and HOLT, E. M.
- Published
- 1994
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305. Integrating global and regional analyses of the effects of climate change: a case study of land use in England and Wales
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Rosenzweig, C., Tranter, R. B., Marsh, J. S., Hossell, J. E., Carson, I. G., Parry, M. L., Bunce, R. G. H., Jones, P. J., Rehman, T., and Fischer, G.
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CROP yields - Published
- 1996
306. The thermoelectric properties of heavily doped hot-pressed germanium-silicon alloys.
- Author
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Rowe, D. M. and Bunce, R. W.
- Published
- 1969
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307. Regression Sampling with Allometrically Related Variables, with Particular Reference to Production Studies
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Bunce, R. G. H. and Mountford, M. D.
- Published
- 1973
308. Woodland Survey of Great Britain 1971-2001.
- Author
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Wood, C. M., Smart, S. M., and Bunce, R. G. H.
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- *
FORESTRY research , *ECOLOGICAL research , *FORESTS & forestry - Abstract
The Woodland Survey of Great Britain is a unique data set, consisting of a detailed range of ecological measurements at a national scale, covering a time span of 30 years. A set of 103 woods spread across Britain were first surveyed in 1971, which were again surveyed in 2000-2003 (for convenience referred to subsequently as the "2001 survey"). Standardised methods of describing the trees, shrubs, ground flora, soils and general habitats present were used for both sets of surveys. The sample of 1648 plots spread through 103 woodland sites located across Britain makes it probably the most extensive quantitative ecological woodland survey undertaken in Britain; it is also notable for the range of sites that have been revisited after such a long interval. The data set provides a unique opportunity to explore the effects of a range of potential drivers of woodland change that operated between 1971 and 2001. The data set is available in four discrete parts, which have been assigned the following DOIs: doi:10.5285/4d93f9ac-68e3-49cf-8a41-4d02a7ead81a (Kirby et al., 2013b), doi:10.5285/d6409d40-58fe-4fa7-b7c8-71a105b965b4 (Kirby et al., 2013d), doi:10.5285/fb1e474d-456b-42a9- 9a10-a02c35af10d2 (Kirby et al., 2013c), doi:10.5285/2d023ce9-6dbe-4b4f-a0cd-34768e1455ae (Kirby et al., 2013a). [ABSTRACT FROM AUTHOR]
- Published
- 2015
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309. High proper motion objects from the UKIDSS Galactic plane survey.
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Smith, Leigh, Lucas, P. W., Bunce, R., Burningham, B., Jones, H. R. A., Smart, R. L., Skrzypek, N., Rodriguez, D. R., Faherty, J., Barentsen, G., Drew, J. E., Andrei, A. H., Catalán, S., Pinfield, D. J., and Redburn, D.
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GALACTIC nuclei , *BROWN dwarf stars , *BINARY stars , *RADIAL velocity of stars , *STAR observations - Abstract
The UKIDSS Galactic Plane Survey (GPS) began in 2005 as a seven year effort to survey ∼1800 deg2 of the northern Galactic plane in the J, H, and K passbands. The survey included a second epoch of K-band data, with a baseline of two to eight years, for the purpose of investigating variability and measuring proper motions. We have calculated proper motions for 167 million sources in a 900 deg2 area located at l > 60° in order to search for new high proper motion objects. Visual inspection has verified 617 high proper motion sources (>200 mas yr−1) down to K = 17, of which 153 are new discoveries. Among these, we have a new spectroscopically confirmed T5 dwarf, an additional T dwarf with estimated type T6, 13 new L dwarf candidates, and two new common proper motion systems containing ultracool dwarf candidates. We provide improved proper motions for an additional 12 high proper motion stars that were independently discovered in the WISE data set during the course of this investigation. [ABSTRACT FROM PUBLISHER]
- Published
- 2014
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310. The photochemistry of a two-carbon ortho-ortho phenyl-bridged 4,4-diphenyl-2-cyclohexen-1-one
- Author
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Bunce, R. A., Taylor, V. L., and Holt, E. M.
- Published
- 1992
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311. Application of robotics In the clinical laboratory
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A. Bunce, R., M. G. Broughton, P., M. Browning, D., E. C. Gibbons, J., and J. Kricka, L.
- Abstract
The basic types of robot are explained, and the performances and costs of some commercial examples are given. The potential advantages and problems of introducing robots into clinical laboratories are identified and the specifcation of a suitable robot is developed. None of the commercially available robots meets all aspects of the specificalion, and currently the purchase of a robot is considered premature for most clinical laboratories.
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- 1989
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312. European farm scale habitat descriptors for the evaluation of biodiversity.
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Herzog, F., Lüscher, G., Arndorfer, M., Bogers, M., Balázs, K., Bunce, R. G. H., Dennis, P., Falusi, E., Friedel, J. K., Geijzendorffer, I. R., Gomiero, T., Jeanneret, P., Moreno, G., Oschatz, M.-L., Paoletti, M. G., Sarthou, J.-P., Stoyanova, S., Szerencsits, E., Wolfrum, S., and Fjellstad, W.
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- *
BIODIVERSITY , *HABITATS - Published
- 2017
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313. Relationships between the species composition of forest field-layer vegetation and environmental drivers, assessed using a national scale survey.
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Corney, P. M., Le Duc, M. G., Smart, S. M., Kirby, K. J., Bunce, R. G. H., and Marrs, R. H.
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SIMULATION methods & models , *FOREST dynamics , *VEGETATION dynamics , *BIOTIC communities , *FOREST microclimatology , *PLANT canopies , *SPATIAL variation , *ENVIRONMENTAL engineering , *PLANT species - Abstract
1 Simulation models of forest stand dynamics have increased understanding of over-storey vegetation functioning, and have facilitated the development of tools capable of assessing possible successional trajectories. However, few models incorporate the response of the field layer vegetation despite it being another key component of forest ecosystems. 2 Our main objective was to assess the degree to which field-layer vegetation composition in forests is determined by variables operating at different scales, from regional (e.g. climate, location) to local factors (e.g. basal area of canopy trees, management). 3 We used data gathered during a nationwide forest survey to assess the relative effects of a broad spectrum of environmental variables on species composition. Variation partitioning was used to examine the relative contribution of subsets of environmental variables such as site spatial variation, boundary type and presence of herbivores. 4 Ordination confirmed hypotheses that field layer vegetation is primarily structured by two composite geo-climatic gradients. However, variation partitioning demonstrated that site- and plot-scale management factors also strongly influence the floristic composition of forest patches. 5 Disturbance variables (site boundary type/regional presence of deer) accounted for considerable species variation, exceeding that due to either site spatial variation or forest structure. 6 This is the first time variation attributable to such a comprehensive range of environmental variables has been quantified for forests surveyed at a national scale. We thus provide a context within which regional studies, or analyses considering a more limited range of factors, can be viewed, and a framework from which robust models of floristic response to gradual and episodic natural and anthropogenic disturbances may be developed. 7 The methodology we present, including a novel technique for the identification and removal of outliers in large data sets, provides a unique and standardized means of assessing the relative importance of diverse environmental drivers across a range of habitat types at the landscape scale, and is readily applicable elsewhere. [ABSTRACT FROM AUTHOR]
- Published
- 2006
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314. Harmonization of the Land Cover Classification System (LCCS) withthe General Habitat Categories (GHC) classification system
- Author
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Valeria Tomaselli, Caspar A. Mücher, Palma Blonda, Vasiliki Kosmidou, Ioannis Manakos, M.M.B. Bogers, Zisis I. Petrou, Richard Lucas, Emilio Padoa-Schioppa, Robert G. H. Bunce, Maria Petrou, Rob H. G. Jongman, Kosmidou, V, Petrou, Z, Bunce, R, Mücher, C, Jongman, R, Bogersc, M, Lucas, R, Tomaselli, V, Blonda, P, PADOA SCHIOPPA, E, Manakosa, I, and Maria Petrou, M
- Subjects
Earth Observation and Environmental Informatics ,010504 meteorology & atmospheric sciences ,Computer science ,0211 other engineering and technologies ,Biodiversity ,General Decision Sciences ,Harmonization ,02 engineering and technology ,Land cover ,Biodiversity and Policy ,01 natural sciences ,Landscape Centre ,Aardobservatie en omgevingsinformatica ,Biodiversiteit en Beleid ,Contextual information ,Ecology, Evolution, Behavior and Systematics ,biodiversity ,021101 geological & geomatics engineering ,0105 earth and related environmental sciences ,BIO/03 - BOTANICA AMBIENTALE E APPLICATA ,Ecology ,business.industry ,Environmental resource management ,Alterra - Centrum Landschap ,15. Life on land ,Habitat ,13. Climate action ,Remote sensing (archaeology) ,Key (cryptography) ,BIO/07 - ECOLOGIA ,Protected area ,business ,Habitat, Land cover, Biodiversity monitoring, Remote sensing, Plant life forms, Strategic survey - Abstract
Monitoring land cover and habitat change is a key issue for conservation managers because of its potential negative impact on biodiversity. The Land Cover Classification System (LCCS) and the General Habitat Categories (GHC) System have been proposed by the remote sensing and ecological research community, respectively, for the classification of land covers and habitats across various scales. Linking the two systems can be a major step forward towards biodiversity monitoring using remote sensing. The translation between the two systems has proved to be challenging, largely because of differences in definitions and related difficulties in creating one-to-one relationships between the two systems. This paper proposes a system of rules for linking the two systems and additionally identifies requirements for site-specific contextual and environmental information to enable the translation. As an illustration, the LCCS classification of the Le Cesine protected area in Italy is used to show rules for translating the LCCS classes to GHCs. This study demonstrates the benefits of a translation system for biodiversity monitoring using remote sensing data but also shows that a successful translation is often depending on the degree of ecological knowledge of the habitats and its relationship with land cover and contextual information.
- Published
- 2014
315. A standardized procedure for surveillance and monitoring European habitats and provision of spatial data
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Rob H. G. Jongman, G. de Blust, H. Skånes, Isabel Loupa Ramos, Marc J. Metzger, Jesper Brandt, David Howard, G. Hofer, Lubos Halada, R.G.H Bunce, Philip Roche, Marta Pérez-Soba, R. Elena-Rosselló, Caspar A. Mücher, G. B. Groom, A. palo, D. Paelinx, Emilio Padoa-Schioppa, P. kovar, Thomas Wrbka, Bunce, R, Metzger, M, Jongman, R, Brandt, J, de Blust, G, Elena Rossello, R, Groom, G, Halada, L, Hofer, G, Howard, D, Kovár, P, Mücher, C, PADOA SCHIOPPA, E, Paelinx, D, Palo, A, Perez Soba, M, Ramos, I, Roche, P, Skånes, H, and Wrbka, T
- Subjects
0106 biological sciences ,010504 meteorology & atmospheric sciences ,Geography, Planning and Development ,01 natural sciences ,Laboratory of Geo-information Science and Remote Sensing ,Wageningen Environmental Research ,biodiversity ,Ecology ,strategic ecological survey ,Environmental resource management ,Centre Geo-information ,PE&RC ,biodiversity, species richness ,raunkiaer plant life forms ,biodiversitet, artsrigdom ,classification ,Milieusysteemanalyse ,surveillance ,Plantenecologie en Natuurbeheer ,BIO/07 - ECOLOGIA ,general habitat categories ,Alterra - Centrum Geo-informatie ,Ecology (disciplines) ,Plant Ecology and Nature Conservation ,Land cover ,principles ,Biology ,stratified sampling ,010603 evolutionary biology ,Landscape Centre ,stratification ,field recording ,Laboratorium voor Geo-informatiekunde en Remote Sensing ,land-cover ,Baseline (configuration management) ,Spatial analysis ,0105 earth and related environmental sciences ,Nature and Landscape Conservation ,Sustainable development ,WIMEK ,business.industry ,Alterra - Centrum Landschap ,15. Life on land ,Field (geography) ,Raunkiaer plant life form ,monitoring ,Environmental Systems Analysis ,dyr og planter ,britain ,Landscape ecology ,business ,Scale (map) - Abstract
Both science and policy require a practical, transmissible, and reproducible procedure for surveillance and monitoring of European habitats, which can produce statistics integrated at the landscape level. Over the last 30 years, landscape ecology has developed rapidly, and many studies now require spatial data on habitats. Without rigorous rules, changes from baseline records cannot be separated reliably from background noise. A procedure is described that satisfies these requirements and can provide consistent data for Europe, to support a range of policy initiatives and scientific projects. The methodology is based on classical plant life forms, used in biogeography since the nineteenth century, and on their statistical correlation with the primary environmental gradient. Further categories can therefore be identified for other continents to assist large scale comparisons and modelling. The model has been validated statistically and the recording procedure tested in the field throughout Europe. A total of 130 General Habitat Categories (GHCs) is defined. These are enhanced by recording environmental, site and management qualifiers to enable flexible database interrogation. The same categories are applied to areal, linear and point features to assist recording and subsequent interpretation at the landscape level. The distribution and change of landscape ecological parameters, such as connectivity and fragmentation, can then be derived and their significance interpreted.
- Published
- 2008
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316. Landscape character assessments and fellow travellers across Europe: a review
- Author
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Groom, G., Wascher, D.M., Potschin, M., Haines-Young, R., Bunce, R. G. H., and Jongman, R. H. G.
- Subjects
Landscape Centre ,Alterra - Centrum Landschap ,Life Science ,Wageningen Environmental Research - Published
- 2006
317. Handbook for Surveillance and Monitoring of European Habitats
- Author
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Bunce, RGH, Groom, GB, Jongman, RHG, PADOA SCHIOPPA, EMILIO, Bunce, R, Groom, G, Jongman, R, and PADOA SCHIOPPA, E
- Subjects
Habitat ,Surveillance ,Monitoring ,Field recording ,Life Forms ,BIO/07 - ECOLOGIA ,Biodiversity ,Stratification - Published
- 2005
318. PROGRAMMED SAMPLE IRRADIATION SYSTEM.
- Author
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Bunce, R
- Published
- 1967
319. Biotope Models and Nature Quality
- Author
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Münier, B., Nygaard, B., Ejrnæs, R., Fredshavn, J. R., Dover, J. W., and Bunce, R. G. H.
- Subjects
poster paper - Published
- 1998
320. Agroforestry research in the hills and uplands
- Author
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Sibbald, A. R., Maxwell, T. J., Griffiths, J. H., Nicholas Hutchings, Taylor, C. M. A., Tabbush, P. M., White, I. M. S., Bell, M., and Bunce, R. G. H.
- Subjects
agroforestry hill upland conservation agriculture
321. Here to Stay, Here to Fight : A Race Today Anthology
- Author
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Field, Paul, Bunce, Robin, Hassan, Leila, Peacock, Margaret, Field, Paul, Bunce, Robin, Hassan, Leila, and Peacock, Margaret
- Published
- 2019
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322. Ammonia-based intermittent aeration control optimized for efficient nitrogen removal.
- Author
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Regmi P, Bunce R, Miller MW, Park H, Chandran K, Wett B, Murthy S, and Bott CB
- Subjects
- Aerobiosis, Alkalies metabolism, Carbon metabolism, Culture Media chemistry, Oxygen analysis, Temperature, Water Purification methods, Ammonia metabolism, Nitrogen metabolism
- Abstract
This work describes the development of an intermittently aerated pilot-scale process (V = 0.45 m(3) ) operated for optimized efficient nitrogen removal in terms of volume, supplemental carbon and alkalinity requirements. The intermittent aeration pattern was controlled using a strategy based on effluent ammonia concentration set-points. The unique feature of the ammonia-based aeration control was that a fixed dissolved oxygen (DO) set-point was used and the length of the aerobic and anoxic time (anoxic time ≥25% of total cycle time) were changed based on the effluent ammonia concentration. Unlike continuously aerated ammonia-based aeration control strategies, this approach offered control over the aerobic solids retention time (SRT) to deal with fluctuating ammonia loading without solely relying on changes to the total SRT. This approach allowed the system to be operated at a total SRT with a small safety factor. The benefits of operating at an aggressive SRT were reduced hydraulic retention time (HRT) for nitrogen removal. As a result of such an operation, nitrite oxidizing bacteria (NOB) out-selection was also obtained (ammonia oxidizing bacteria [AOB] maximum activity: 400 ± 79 mgN/L/d, NOB maximum activity: 257 ± 133 mgN/L/d, P < 0.001) expanding opportunities for short-cut nitrogen removal. The pilot demonstrated a total inorganic nitrogen (TIN) removal rate of 95 ± 30 mgN/L/d at an influent chemical oxygen demand: ammonia (COD/NH4 (+) -N) ratio of 10.2 ± 2.2 at 25°C within the hydraulic retention time (HRT) of 4 h and within a total SRT of 5-10 days. The TIN removal efficiency up to 91% was observed during the study, while effluent TIN was 9.6 ± 4.4 mgN/L. Therefore, this pilot-scale study demonstrates that application of the proposed on-line aeration control is capable of relatively high nitrogen removal without supplemental carbon and alkalinity addition at a low HRT., (© 2015 Wiley Periodicals, Inc.)
- Published
- 2015
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323. Extrapolation of in situ data from 1-km squares to adjacent squares using remote sensed imagery and airborne lidar data for the assessment of habitat diversity and extent.
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Lang M, Vain A, Bunce RG, Jongman RH, Raet J, Sepp K, Kuusemets V, Kikas T, and Liba N
- Subjects
- Environment, Estonia, Light, Biodiversity, Ecosystem, Environmental Monitoring methods, Satellite Imagery
- Abstract
Habitat surveillance and subsequent monitoring at a national level is usually carried out by recording data from in situ sample sites located according to predefined strata. This paper describes the application of remote sensing to the extension of such field data recorded in 1-km squares to adjacent squares, in order to increase sample number without further field visits. Habitats were mapped in eight central squares in northeast Estonia in 2010 using a standardized recording procedure. Around one of the squares, a special study site was established which consisted of the central square and eight surrounding squares. A Landsat-7 Enhanced Thematic Mapper Plus (ETM+) image was used for correlation with in situ data. An airborne light detection and ranging (lidar) vegetation height map was also included in the classification. A series of tests were carried out by including the lidar data and contrasting analytical techniques, which are described in detail in the paper. Training accuracy in the central square varied from 75 to 100 %. In the extrapolation procedure to the surrounding squares, accuracy varied from 53.1 to 63.1 %, which improved by 10 % with the inclusion of lidar data. The reasons for this relatively low classification accuracy were mainly inherent variability in the spectral signatures of habitats but also differences between the dates of imagery acquisition and field sampling. Improvements could therefore be made by better synchronization of the field survey and image acquisition as well as by dividing general habitat categories (GHCs) into units which are more likely to have similar spectral signatures. However, the increase in the number of sample kilometre squares compensates for the loss of accuracy in the measurements of individual squares. The methodology can be applied in other studies as the procedures used are readily available.
- Published
- 2015
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324. Using patient passports to improve A&E asthma care.
- Author
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Newell K, Bunce R, and Hume S
- Subjects
- Adolescent, Adult, Child, Emergencies, Female, Humans, Male, Middle Aged, United Kingdom, Young Adult, Asthma therapy, Patient Care Planning organization & administration, Patient Identification Systems, State Medicine organization & administration
- Abstract
The asthma patient passport (APP) is a patient-specific asthma plan that details what to do when asthma is out of control. It helps patients who have severe, difficult-to-manage asthma, and health professionals when these patients present at accident and emergency. This article shows that, while the APP acts as a patient's advocate, it also facilitates accessing emergency care by making it more streamlined. Case studies explore why people with asthma have avoided going to A&E, putting their lives at risk, and provide an insight into how difficult it can be for people to navigate the healthcare system when they are at their most vulnerable.
- Published
- 2015
325. Control of aeration, aerobic SRT and COD input for mainstream nitritation/denitritation.
- Author
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Regmi P, Miller MW, Holgate B, Bunce R, Park H, Chandran K, Wett B, Murthy S, and Bott CB
- Subjects
- Bacteria metabolism, Biological Oxygen Demand Analysis, Bioreactors microbiology, Carbon metabolism, Oxidation-Reduction, Oxygen metabolism, Pilot Projects, Time Factors, Wastewater analysis, Ammonia metabolism, Nitrates metabolism, Nitrites metabolism, Waste Disposal, Fluid methods
- Abstract
This work describes the development of an intermittently aerated pilot-scale process (V = 0.34 m(3)) operated without oxidized nitrogen recycle and supplemental carbon addition optimized for nitrogen removal via nitritation/denitritation. The aeration pattern was controlled using a novel aeration strategy based on set-points for reactor ammonia, nitrite and nitrate concentrations with the aim of maintaining equal effluent ammonia and nitrate + nitrite (NOx) concentrations. Further, unique operational and process control strategies were developed to facilitate the out-selection of nitrite oxidizing bacteria (NOB) based on optimizing the chemical oxygen demand (COD) input, imposing transient anoxia, aggressive solids retention time (SRT) operation towards ammonia oxidizing bacteria (AOB) washout and high dissolved oxygen (DO) (>1.5 mg/L). Sustained nitrite accumulation (NO2-N/NOx-N = 0.36 ± 0.27) was observed while AOB activity was greater than NOB activity (AOB: 391 ± 124 mgN/L/d, NOB: 233 ± 151 mgN/L/d, p < 0.001) during the entire study. The reactor demonstrated total inorganic nitrogen (TIN) removal rate of 151 ± 74 mgN/L/d at an influent COD/ [Formula: see text] -N ratio of 10.4 ± 1.9 at 25 °C. The TIN removal efficiency was 57 ± 25% within the hydraulic retention time (HRT) of 3 h and within an SRT of 4-8 days. Therefore, this pilot-scale study demonstrates that application of the proposed online aeration control is able to out-select NOB in mainstream conditions providing relatively high nitrogen removal without supplemental carbon and alkalinity at a low HRT., (Copyright © 2014 Elsevier Ltd. All rights reserved.)
- Published
- 2014
- Full Text
- View/download PDF
326. Inhibition of antibiotic-resistant Staphylococcus aureus by the broad-spectrum dihydrofolate reductase inhibitor RAB1.
- Author
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Bourne CR, Barrow EW, Bunce RA, Bourne PC, Berlin KD, and Barrow WW
- Subjects
- Anti-Bacterial Agents chemistry, Enzyme Inhibitors chemistry, Inhibitory Concentration 50, Microbial Sensitivity Tests, Protein Structure, Secondary, Protein Structure, Tertiary, Tetrahydrofolate Dehydrogenase chemistry, Anti-Bacterial Agents pharmacology, Enzyme Inhibitors pharmacology, Staphylococcus aureus drug effects, Staphylococcus aureus enzymology, Tetrahydrofolate Dehydrogenase metabolism
- Abstract
The bacterial burden on human health is quickly outweighing available therapeutics. Our long-term goal is the development of antimicrobials with the potential for broad-spectrum activity. We previously reported phthalazine-based inhibitors of dihydrofolate reductase (DHFR) with potent activity against Bacillus anthracis, a major component of Project BioShield. The most active molecule, named RAB1, performs well in vitro and, in a cocrystal structure, was found deep within the active site of B. anthracis DHFR. We have now examined the activity of RAB1 against a panel of bacteria relevant to human health and found broad-spectrum applicability, particularly with regard to gram-positive organisms. RAB1 was most effective against Staphylococcus aureus, including methicillin- and vancomycin-resistant (MRSA/VRSA) strains. We have determined the cocrystal structure of the wild-type and trimethoprim-resistant (Phe 98 Tyr) DHFR enzyme from S. aureus with RAB1, and we found that rotational freedom of the acryloyl linker region allows the phthalazine moiety to occupy two conformations. This freedom in placement also allows either enantiomer of RAB1 to bind to S. aureus, in contrast to the specificity of B. anthracis for the S-enantiomer. Additionally, one of the conformations of RAB1 defines a unique surface cavity that increases the strength of interaction with S. aureus. These observations provide insights into the binding capacity of S. aureus DHFR and highlight atypical features critical for future exploitation in drug development.
- Published
- 2010
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327. An assessment of long term ecosystem research activities across European socio-ecological gradients.
- Author
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Metzger MJ, Bunce RG, van Eupen M, and Mirtl M
- Subjects
- Europe, Research, Ecology, Ecosystem
- Abstract
Integration of European long term ecosystem research (LTER) would provide important support for the management of the pan-European environment and ecosystems, as well as international policy commitments. This does require appropriate coverage of Europe and standardised frameworks and research methods between countries. Emerging interest in socio-ecological systems prompted the present assessment of the distribution of LTER activities across European socio-ecological gradients. This paper presents a European stratification with a 1 km(2) resolution, delineating 48 broad socio-ecological regions. The dataset is based on an existing biogeophysical stratification constructed using multivariate clustering of mainly climatic variables and a newly developed socio-economic stratification based on an economic density indicator. The coverage of European LTER facilities across the socio-ecological gradients is tested using this dataset. The analysis shows two strong biases in the present LTER effort. Firstly, urban and disturbed regions are consistently under-represented, illustrating a bias for traditional ecological research away from human activity. Secondly, the Mediterranean, for which some of the most extreme global change impacts are projected, is receiving comparatively little attention. Both findings can help guide future investment in the European LTER network - and especially in a Long Term Socio-Ecological Research (LTSER) component- to provide a more balanced coverage. This will provide better scientific understanding of pan-European environmental concerns and support the management of natural resources and international policy commitments in the European Union., ((c) 2010 Elsevier Ltd. All rights reserved.)
- Published
- 2010
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328. Assessing stock and change in land cover and biodiversity in GB: an introduction to Countryside Survey 2000.
- Author
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Firbank LG, Barr CJ, Bunce RG, Furse MT, Haines-Young R, Hornung M, Howard DC, Sheail J, Sier A, and Smart SM
- Subjects
- Animals, Data Collection, Environment, Plants, United Kingdom, Ecosystem, Environment Design, Environmental Monitoring
- Abstract
Countryside Survey 2000 (CS2000) is the latest in a series of surveys designed to measure and evaluate stock and change of land cover, landscape features, freshwaters, habitats and the vegetation of Great Britain. The ideas behind CS2000 developed during the 1960s and 1970s and culminated in the first survey of vegetation and land cover in 1978. One kilometer sample squares were selected at random using an environmental stratification. Subsequent surveys took place in 1984, 1990 and 1998, revisiting the original sample locations, whilst progressively expanding in scope and sample size; CS2000 included soils, breeding birds, remotely sensed imagery, freshwater biota and hydromorphology. Countryside Survey data may be interpreted using the pressure-state-response model, by selecting indicators of process and quality, and by identifying models of expected responses to different pressures. Thus, results showing losses of hedgerows between 1984 and 1990 stimulated new protection for these features. Ideally, CS2000 data should be used to stimulate experiments to distinguish between different pressures, in order to ensure that policy and management responses are both appropriate and achievable.The experience from CS2000 may prove helpful for the design and management of other large scale monitoring programmes of ecosystems. In particular, the scope of the survey, and the use to which the data are applied, have evolved through time, and yet continuity was essential for change to be detected efficiently. These objectives were reconciled by collecting the data in a disaggregated form, allowing a high degree of flexibility in both analysis and reporting.
- Published
- 2003
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329. National-scale vegetation change across Britain; an analysis of sample-based surveillance data from the Countryside Surveys of 1990 and 1998.
- Author
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Smart SM, Clarke RT, van de Poll HM, Robertson EJ, Shield ER, Bunce RG, and Maskell LC
- Subjects
- Data Collection, Ecosystem, Light, Nitrogen, Phosphorus, Population Dynamics, United Kingdom, Conservation of Natural Resources, Environmental Monitoring, Plants
- Abstract
Patterns of vegetation across Great Britain (GB) between 1990 and 1998 were quantified based on an analysis of plant species data from a total of 9596 fixed plots. Plots were established on a stratified random basis within 501 1 km sample squares located as part of the Countryside Survey of GB. Results are primarily conveyed in terms of a classification of national land-cover into 22 mutually exclusive Broad Habitat types. Each of the fixed vegetation plots could be assigned to the Broad Habitat in which they were located in either year. Two types of analysis are reported, both based on changes in plant species composition within monitoring plots. The first examined turnover and net change between Broad Habitat types. The second quantified more subtle changes that had occurred within each Broad Habitat using a series of condition measures that summarized multivariate plant species data as a single scalar value for each plot at each time. There are major difficulties in using uncontrolled, large-scale surveillance data to unravel causal linkages and no attempt was made to quantitatively partition variation among competing causes. However, it was clear that results were broadly consistent with environmental drivers known to have operated prior to and during the survey interval. Large-scale vegetation changes could be summarized in terms of shifts along gradients of substrate fertility and disturbance. Changes implied increased nutrient availability across upland and lowland ecosystems while, in lowland landscapes, linear features and small biotope fragments saw a marked shift to species compositions associated with greater shade and less disturbance.
- Published
- 2003
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330. A comparison of different biogeographical classifications of Europe, Great Britain and Spain.
- Author
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Bunce RG, Carey PD, Elena-Rossello R, Orr J, Watkins J, and Fuller R
- Subjects
- England, Europe, Reference Values, Spain, Climate, Environment, Geographic Information Systems, Models, Theoretical
- Abstract
Various biogeographical and bioclimatic classifications of a number of regions, countries and continents have been created to meet different objectives. A policy maker might ask the question 'why is there no single accepted classification and how do the different classifications compare with one another?' In order to answer these two questions three classifications created by different methods for Great Britain and two for Spain are compared using the Kappa statistic. All of the classifications were created from data on cellular grids with a set window size. Further non-statistical comparisons are made with other classifications. The biogeographic classifications studied in this paper produced three different types of zone: those that were always identified whatever the method; those that were broadly similar but where the boundaries differed; and those that were unique to a particular classification. These different types of zone are likely to exist for any comparison between classifications of a particular region. The extent of the geographic window from which data were obtained had a major effect on the classification of grid cells at the edges of the window. For example, the few grid cells in the south of England, with characteristics of continental Europe, are not detected if data from Great Britain alone are used for the classification. We conclude that the data window should always be larger than the area for which the classification is being made. The objective Kappa statistic, although useful, was not capable of discerning similarities and dissimilarities that appear obvious to the subjective human eye. Although the details of the classifications differed there were broad similarities between the classifications and these differences reflect important divisions along major environmental axes that have been inferred by earlier biogeographers. As the divisions are real there is a sound basis for their use in future land use or environmental policy.
- Published
- 2002
- Full Text
- View/download PDF
331. Diastereoselective synthesis of substituted tetrahydroquinoline-4-carboxylic esters by a tandem reduction-reductive amination reaction.
- Author
-
Bunce RA, Herron DM, Johnson LB, and Kotturi SV
- Subjects
- Stereoisomerism, Esters chemical synthesis, Quinolines chemical synthesis
- Abstract
A diastereoselective synthesis of 1-methyl-2-alkyl- and 2-alkyl-1,2,3,4-tetrahydroquinoline-4-carboxylic esters has been developed from methyl (2-nitrophenyl)acetate (1). The method involves alkylation of 1 with an allylic halide, ozonolysis of the double bond, and catalytic hydrogenation. The final hydrogenation initiates a tandem sequence involving (1) reduction of the aromatic nitro group, (2) condensation of the aniline or hydroxylamine(8) nitrogen with the side chain carbonyl, (3) reduction of the resulting nitrogen intermediate, and (4) reductive amination of the tetrahydroquinoline with formaldehyde produced in the ozonolysis to give a methyl (+/-)-1-methyl-2-alkyl-1,2,3,4-tetrahydroquinoline-4-carboxylate. Removal of the formaldehyde prior to hydrogenation gives the simple (+/-)-2-alkyl derivatives. The products are isolated in high yield as single diastereomers having the C-2 alkyl group cis to the C-4 carboxylic ester. The reaction has been extended to the synthesis of tricyclic structures with similar high diastereoselection.
- Published
- 2001
- Full Text
- View/download PDF
332. Aryl-fused nitrogen heterocycles by a tandem reduction--Michael addition reaction.
- Author
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Bunce RA, Herron DM, and Ackerman ML
- Subjects
- Oxidation-Reduction, Spectrum Analysis, Heterocyclic Compounds chemistry, Nitrogen chemistry
- Published
- 2000
- Full Text
- View/download PDF
333. An electrochemical study of the factors responsible for modulating the reduction potential of putidaredoxin.
- Author
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Avila L, Wirtz M, Bunce RA, and Rivera M
- Subjects
- Amino Acid Sequence, Base Sequence, Cytochrome P-450 Enzyme System chemistry, Electrochemistry, Electron Transport, Escherichia coli, Ferredoxins genetics, Models, Molecular, Molecular Sequence Data, Oxidation-Reduction, Polylysine chemistry, Ferredoxins chemistry
- Abstract
The gene coding for putidaredoxin has been synthesized using a combination of chemical and enzymatic methods and subsequently expressed in Escherichia coli. The recombinant protein characterized by electronic spectroscopy, mass spectrometry, and electrochemistry was found to be identical to putidaredoxin obtained from Pseudomonas putida. Polylysine was found to promote the fast and reversible electrochemistry of putidaredoxin at negatively charged electrodes such as indium-doped tin oxide or gold surfaces modified with mercaptoalkanoate groups. The value of the heterogeneous electron transfer rate constant obtained from solutions containing a mixture of putidaredoxin and polylysine (k(s) = 1.3 x 10(-3) cm/s) is one order of magnitude larger than the values reported previously at gold electrodes modified with mercaptoethylamine or at antimony-doped tin oxide semiconductor electrodes. It was observed that when the reduction potential of putidaredoxin is measured by cyclic voltammetry, the resultant value is consistently more positive (64 mV) than the reduction potential measured with potentiometric titrations. A comparison between the electrochemical responses of putidaredoxin and spinach ferredoxin, combined with the examination of their corresponding three-dimensional structures, indicates that the positive shift in the reduction potential of putidaredoxin originates from the formation of a transient complex between putidaredoxin and polylysine at the electrode surface. The formation of this transient complex modulates the reduction potential of putidaredoxin by lowering the value of the dielectric constant around its iron-sulfur cluster microenvironment, specifically by neutralizing negative charges surrounding the active site and by excluding water from the solvent exposed iron sulfur cluster. The observed positive shift in E degrees ', which is induced by complexation with polylysine at the electrode-surface, suggests that similar factors are likely to contribute to the anodic shift in the E degrees ' of cytochrome P450(cam)-bound putidaredoxin (+44 mV) with respect to the E degrees ' measured for free putidaredoxin.
- Published
- 1999
- Full Text
- View/download PDF
334. Complete isomer-specific 1H and 13C NMR assignments of the heme resonances of rat liver outer mitochondrial membrane cytochrome b5.
- Author
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Rivera M, Qiu F, Bunce RA, and Stark RE
- Subjects
- Aminolevulinic Acid chemistry, Animals, Carbon Isotopes, Intracellular Membranes enzymology, Isomerism, Isotope Labeling methods, Magnetic Resonance Spectroscopy methods, Protons, Rats, Cytochromes b5 chemistry, Heme chemistry, Mitochondria, Liver enzymology
- Abstract
Singly and doubly labeled delta-aminolevulinic acid derivatives were used to prepare rat liver outer mitochondrial membrane (OM) cytochrome b5 containing a 13C-labeled heme active site. A variety of NMR experiments, including HMBC and INADEQUATE in conjunction with the more commonly used HMQC, NOESY, and COSY, were conducted to make unambiguous assignments of protonated carbons and the quaternary pyrrole-alpha and -beta carbons in both isomeric forms of the paramagnetic active center of OM cytochrome b5. Because the long interpulse delays in the HMBC experiment have a detrimental effect on the detectability of fast relaxing paramagnetically affected resonances. INADEQUATE is proposed as the experiment of choice for assigning quaternary carbons in paramagnetic hemes with carefully chosen macrocycle labeling patterns. Furthermore, the applicability of the INADEQUATE experiment to paramagnetic heme active sites should be facilitated greatly by the availability of biosynthetic methods for producing isotopically labeled b-hemes and, more recently, isotopically labeled c-hemes.
- Published
- 1999
- Full Text
- View/download PDF
335. A simple near-patient test for nicotine and its metabolites in urine to assess smoking habit.
- Author
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Cope G, Nayyar P, Holder R, Gibbons J, and Bunce R
- Subjects
- Chromatography, Gas standards, Cotinine standards, Cotinine urine, Disposable Equipment, Humans, Nicotine analogs & derivatives, Reagent Kits, Diagnostic standards, Smoking psychology, Nicotine metabolism, Nicotine urine, Smoking urine
- Abstract
We describe a disposable, near-patient urine test to monitor cigarette smoking. A plastic device contains the sealed dried reagents to measure nicotine and its metabolites, by a colorimetric assay. The device can be used to give a qualitative assessment of tobacco consumption, simply by observing a colour change. Alternatively, the test can be quantified by measuring the light absorbance with a simple colorimeter, and a concentration of nicotinic metabolites obtained with reference to a cotinine standard. A correction factor for the concentration of the urine sample, based on light absorbance, allows the result to be expressed as a ratio to urine concentration. This method correlates with reported daily cigarette consumption (r = 0.69, p < 0.0001) and compares favourably with cotinine, as measured by gas chromatography (r = 0.89, p < 0.0001). The method provides a simple-to-use, inexpensive way to monitoring tobacco consumption in extralaboratory situations.
- Published
- 1996
- Full Text
- View/download PDF
336. 13C NMR spectroscopic and X-ray crystallographic study of the role played by mitochondrial cytochrome b5 heme propionates in the electrostatic binding to cytochrome c.
- Author
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Rodríguez-Marañón MJ, Qiu F, Stark RE, White SP, Zhang X, Foundling SI, Rodríguez V, Schilling CL 3rd, Bunce RA, and Rivera M
- Subjects
- Animals, Binding Sites, Carbon Isotopes, Cattle, Crystallography, X-Ray, Heme metabolism, Horses, Intracellular Membranes metabolism, Kinetics, Magnetic Resonance Spectroscopy, Mitochondria, Heart metabolism, Mitochondria, Liver metabolism, Models, Chemical, Models, Molecular, Osmolar Concentration, Rats, Static Electricity, Cytochrome c Group chemistry, Cytochrome c Group metabolism, Cytochromes b5 chemistry, Cytochromes b5 metabolism, Heme chemistry, Protein Structure, Secondary
- Abstract
The role played by the outer mitochondrial membrane (OM) cytochrome b5 heme propionate groups in the electrostatic binding between OM cytochrome b5 and horse heart cytochrome c was investigated by 13C NMR spectroscopy and X-ray crystallography. To achieve these aims, 13C-labeled heme OM cytochrome b5 was expressed in Escherichia coli as previously described [Rivera M., Walker, F.A. (1995) Anal. Biochem. 230, 295-302]. Assignment of the resonances arising from the heme propionate carbons in ferricytochrome b5 was carried out by a combination of one- and two-dimensional NMR experiments. Titrations of [13C]heme-labeled OM cytochrome b5 with horse heart cytochrome c were carried out in order to monitor the resonances arising from the heme propionate carbonyl carbons in OM cytochrome b5. The results from these titrations clearly show that only the heme propionate located on the exposed heme edge in OM cytochrome b5 participates in the electrostatic stabilization of the complex between OM cytochrome b5 and horse heart cytochrome c. Similar experiments carried out monitoring 13C resonances arising from several other heme substituents demonstrated that the stoichiometry of the complex is 1:1. A conditional binding constant, K which equals 3.8 x 10(4) +/- 1.4 x 10(4) at mu = 0.02 M, was obtained for the formation of the complex by fitting the binding curves obtained experimentally to a model based on this stoichiometry. The X-ray crystal structure of rat liver OM cytochrome b5 solved to 2.7 A resolution shows that the structures of bovine liver microsomal cytochrome b5 and rat liver OM cytochrome b5 are almost identical when compared at medium resolution. The similarity between the two structures, combined with the findings that only the heme propionate located on the exposed heme edge of OM cytochrome b5 participates in the electrostatic binding to cytochrome c and that the stability of this complex is similar to that measured for the association between microsomal cytochrome b5 and cytochrome c, clearly indicates that the site of interaction on OM cytochrome b5 is almost identical to the one elucidated for microsomal cytochrome b5. It is therefore possible to conclude that the large body of information gathered by many investigators for the nonphysiological interaction between microsomal cytochrome b5 and cytochrome c (recently reviewed) [Mauk, A. G. Mauk, M. R., Moore, G. R., & Northrup, S. H. (1995) Bioenerg. Biomembr. 27, 311-330] has indeed biological as well as pedagogical validity.
- Published
- 1996
- Full Text
- View/download PDF
337. Histidine decarboxylase activity in trauma-resistant rats.
- Author
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Reichard SM, Bunce R, and Galvin MJ Jr
- Subjects
- Animals, Blood Volume, Female, Hemoglobinometry, Histidine Decarboxylase blood, Rats, Carboxy-Lyases metabolism, Histidine Decarboxylase metabolism, Lung enzymology, Shock, Traumatic enzymology, Spleen enzymology
- Abstract
Studies have been carried out to determine the possible role of nascent histamine in the development of traumatic shock. This was done by examining histidine decarboxylase (HD) activity of the lung, spleen, and plasma following exposure to trauma in normal and trauma-resistant rats. In normal rats, there was a significant increase in lung HD activity at 15 min and 4 h; and in the spleen the HD activity increased significantly at 4 h. In trauma-resistant rats exposed to trauma, there were no changes in enzyme activity in the lung and less pronounced changes in the spleen. The plasma HD activity remained stable in normal and resistant rats following episodes of trauma. Changes in total erythrocyte hemoglobin were observed in both normal and trauma-adapted rats following exposure to this stress, increasing significantly in normal rats, but decreasing in trauma-resistant rats. Blood volume decreased significantly at 4 h after trauma in normal animals; whereas only a slight decrease was noted in resistant animals. The data support the concept that newly formed histamine contributes to the pathogenesis of shock. It is also proposed that the increased resistance, characteristic of trauma-adapted rats, could be partly due to an inhibition of enzyme activation following trauma.
- Published
- 1976
- Full Text
- View/download PDF
338. Histidine decarboxylase activity in traumatic shock.
- Author
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Galvin MJ Jr, Bunce R, and Reichard SM
- Subjects
- Animals, Carboxy-Lyases blood, Female, Histidine, Rats, Spleen enzymology, Time Factors, Carboxy-Lyases metabolism, Lung enzymology, Shock, Traumatic enzymology
- Published
- 1974
- Full Text
- View/download PDF
339. Camera luminometer for use with luminescent assays.
- Author
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Bunce RA, Thorpe GH, Gibbons JE, Killeen PR, Ogden G, Kricka LJ, and Whitehead TP
- Subjects
- Humans, Luminol, Photography, Ferritins blood, Luminescence
- Published
- 1985
- Full Text
- View/download PDF
340. A mercuric iodide detector unit implantable and externally powered for use in radionuclide tracer studies in small animals.
- Author
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Singh B, Vadstrup S, Pearce G, Bunce RW, and Bojsen J
- Subjects
- Animals, Cricetinae, Iodides, Mercury, Mercury Compounds, Radioactive Tracers, Radioisotopes
- Abstract
A small externally powered implantable gamma-radiation detector unit (35 X 12 mm diameter containing a mercuric iodide detector (HgI2), charge amplifier, radiotransmitter and an inductive power supply has been constructed. Since the total weight of the device is 5 g, it is suitable for implantation in laboratory animals such as rats or hamsters. A comparison between the implanted HgI2 detector unit and a conventional stationary 2 X 2 inch NaI(TI) detector has been performed by simultaneous measurements of the 133Xe clearance from a depot. Using 125I-iothalamate a kidney function study of an unrestrained hamster is shown as an example of measurements in the unrestrained animal.
- Published
- 1981
341. A syringe system for rapid and accurate pipetting of microlitre samples of serum.
- Author
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Bradwell AR and Bunce RA
- Subjects
- Blood Proteins analysis, Blood Chemical Analysis instrumentation, Syringes
- Published
- 1976
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