799 research outputs found
Land use and season affect fluxes of CO2, CH4, CO, N2O, H2 and isotopic source signatures in Panama : evidence from nocturnal boundary layer profiles
No full textConversion of tropical rainforests to pastures and plantations is associated with changes in soil properties and biogeochemical cycling, with implications for carbon cycling and trace gas fluxes. The stable isotopic composition of ecosystem respiration (δ13CR and δ18OR) is used in inversion models to quantify regional patterns of CO2 sources and sinks, but models are limited by sparse measurements in tropical regions. We measured soil respiration rates, concentrations of CO2, CH4, CO, N2O and H2 and the isotopic composition of CO2, CH4 and H2 at four heights in the nocturnal boundary layer (NBL) above three common land-use types in central Panama, during dry and rainy seasons. Soil respiration rates were lowest in Plantation (average 3.4 μmol m-2 s-1), highest in Pasture (8.3 μmol m-2 s-1) and intermediate in Rainforest (5.2 μmol m-2 s-1) δ13CR closely reflected land use and increased during the dry season where C3 vegetation was present δ18OR did not differ by land use but was lower during the rainy than the dry season. CO2 was correlated with other species in approximately half of the NBL profiles, allowing us to estimate trace gas fluxes that were generally within the range of literature values. The Rainforest soil was a sink for CH4 but emissions were observed in Pasture and Plantation, especially during the wet season. N2O emissions were higher in Pasture and Plantation than Rainforest, contrary to expectations. Soil H2 uptake was highest in Rainforest and was not observable in Pasture and Plantation during the wet season. We observed soil CO uptake during the dry season and emissions during the wet season across land-use types. This study demonstrated that strong impacts of land-use change on soil-atmosphere trace gas exchange can be detected in the NBL, and provides useful observational constraints for top-down and bottom-up biogeochemistry models
The formula for the fermenting capacity of a single cell
No full textIn his criticism of the paper of Bayne-Jones and Rhees (1929), Wetzel (1929) claims that the rate of heat production of a single bacterium in these experiments cannot be represented by the Buchanan formula. Since there is no essential difference between heat production and the formation of any other fermentation prod-ucts, the Buchanan formula could not be applied anywhere if Wetzel's criticisms were justified. The author believes, however, that Wetzel's deductions have missed the essential point. To understand this, we must go back to the historical development of the formula. If multiplying cells cause a fermentation, the rate of fermenta-tion can be stated correctly only by determining the amount of product formed per cell and per hour. This can be estimated by taking the average between the initial count of bacteria a and the final count b, and dividing the total amount of products S by this. average and by the time t. Thus, the fermenting capacity per cell and hour would be S 2S x = t (a + b) t (a + b) Since the simple average does not actually present the average number of fermenting cells in a rapidly multiplying culture, Rahn (1912) developed the following formula S (log b- log a) t (b- a) 0.301 This formula was developed and used for short time intervals only; t did not mean the entire time of the experiment, but th
All-in all-out magnetic order and propagating spin-waves in Sm2Ir2O7
No full textUsing resonant magnetic x-ray scattering we address the unresolved nature of the magnetic groundstate and the low-energy effective Hamiltonian of Sm2Ir2O7, a prototypical pyrochlore iridate with a finite temperature metal-insulator transition. Through a combination of elastic and inelastic measurements, we show that the magnetic ground state is an all-in all-out (AIAO) antiferromagnet. The magnon dispersion indicates significant electronic correlations and can be well-described by a minimal Hamiltonian that includes Heisenberg exchange (J = 27.3(6) meV) and DzyaloshinskiiMoriya interaction (D = 4.9(3) meV), which provides a consistent description of the magnetic order and excitations. In establishing that Sm2Ir2O7 has the requisite inversion symmetry preserving AIAO magnetic groundstate, our results support the notion that pyrochlore iridates may host correlated Weyl semimetals
Kognitive Leistungen und Adhärenzverhalten bei Patienten mit schizophrenen Psychosen
No full textSpiekermann A, Schulz M, Behrens J, Driessen M, Rahn E, Beblo T. Kognitive Leistungen und Adhärenzverhalten bei Patienten mit schizophrenen Psychosen. Fortschritte der Neurologie · Psychiatrie. 2011;79(02):73-82.Hintergrund: Es ist bekannt, dass viele Patienten mit schizophrenen Erkrankungen Non-Adhärenz bzgl. der regelmäßigen Einnahme antipsychotischer Medikamente zeigen. Zum anderen weisen viele Studien auf kognitive Defizite der Betroffenen hin. In dieser Übersichtsarbeit sollen die Ergebnisse von Studien, die den Zusammenhang von Non-Adhärenz und kognitiver Leistungsfähigkeit untersucht haben, gegenübergestellt werden. Methode: Mittels einer systematischen Literaturrecherche wurde der Zusammenhang kognitiver Leistungsparameter mit dem Ausmaß der Adhärenz schizophrener Patienten untersucht. Ergebnisse: Es konnten 18 Studien ermittelt werden, in welchen der Zusammenhang zwischen kognitiver Leistungsfähigkeit und adhärentem Verhalten untersucht wurde. Ein Großteil der Studien belegt, dass Patienten mit stärkeren kognitiven Beeinträchtigungen weniger adhärentes Verhalten zeigen. Die möglichen kausalen Mechanismen dieses Zusammenhangs werden diskutiert
Behaviour of buried pipelines subjected to external loading.
No full textThe research presented in this Thesis was carried out at the University of Sheffield under
the supervision of Dr I. C. Pyrah and Dr W. F. Anderson, and Mr G. Leach at British Gas
Engineering Research Station (ERS). The research was financially supported by a British
Gas Research Scholarship and by the Overseas Research Students Awards Scheme.
The Author would like to express his sincere gratitude to his supervisors for their invaluable
help, guidance and encouragement during the development of the research.
The Author is also grateful to Dr S. R. Mi for his interest and assistance throughout the
research. Special thanks also go to Dr S. J. Wheeler for his supervision during the first year
of the research and sound advice in the initial stage of the work.
The Author would like to express his gratitude to all members of the geotechnics group at
the University of Sheffield for the useful discussions and comments. Special thanks and
appreciation are extended to the staff at the ERS, particularly Mr E. Middleton for
providing the data of the field tests and constructive comments.
The laboratory tests were performed at ERS Soils Laboratory for which the Author is
thankful to the laboratory staff. The Author must also thank British Gas for providing the
computer hardware and software for performing the numerical analyses, and the printing
facilities to produce the Thesis. Thanks also go to Mr D. Reay and Mr B. Bellwood at the
Gas Research Centre of British Gas for ensuring continuous financial support throughout
the award period.
Finally, the Author wishes to thank his family and friends for their endless support and
encouragement throughout the period of study in the UK. Without them, this Thesis may
never have been completed
The New Mercersburg Review, no. 10
No full textDigitized copy of the Autumn 1991 issue, Journal of the Mercersburg Society. Electronic PDF document. 61 pages.Contents: Editorial Introduction -- Ecumenical Efforts at Liturgical Reconciliation: Word and Sacrament / Horace T. Allen, Jr. -- The Formative Character of Liturgy: An Anglican Perspective for the Oecumene / David R. Holeton -- With All the Saints: Ecumenical Liturgics and Mercersburg Theology / Deborah Rahn Clemens -- Mercersburg and Old First / Robert A. Schneider -- This May Sound Mystical, But... A Sermon / Linden J. De Bie -- Holding and Folding: A Sermon / Wayne L. Smith
Economic and Religious Significance of the Islamic and Conventional Pawnbroking in Malaysia: Behavioural and Perception Analysis
No full textOperating alongside with the formal financial sector, there has been less recognition about the important role played by informal finance through their complementary role in providing credit to the society. Among informal finance, pawnshop has grown in importance over the past few years especially during the tough economic climate. In Malaysia for instance, the pawnbroking business has served people in need of small instant cash since the 19th century in various forms. Due to the excessive interest rate and other malpractices imposed by the conventional pawnshops, Malaysian government initiated the first Islamic pawnbroking in 1992 which was set up by the Terengganu Islamic Religious and Malay Customs Council namely as the Muassasah Gadaian Islam Terengganu, which has experienced an overwhelming success in terms of expanding in the informal economy. In 2010, there were 329 of institutions offering Islamic pawnbroking operating side by side with 259 licensed conventional pawnshops which shows a remarkable increase in the Islamic pawnbroking.
Given this background, the research aim is to explore and analyse the socio-economic consequences of pawnshops crediting in Malaysia through the perceptions of the participants. In doing so, this study will examine the factors determining people’s preferences for pawnshop and also exploring the perceptions and opinions of the customers and the participating pawnbrokers in Malaysia on various aspects and consequences of pawnbroking. Importantly, it will analyse specifically the impact of Islamic pawnbroking on the socio-economy of the Malaysian society.
In an attempt to fulfill the aims of the research study, first, the questionnaires survey were administered to both customers and pawnbrokers of the conventional and Islamic pawnshops in order to distinguish the processes of lending, factors determining pawnshops’ selection, and also the perceptions of Malaysian customers and pawnbrokers regarding the role of pawnshop institution in social development hence in economic development related issues. Second, a semi-structured interview were subsequently conducted with the leading individuals of the Islamic pawnbrokers in order to develop in-depth ideas and understanding about the underlying principle of Islamic pawnbroking and other issues related. Furthermore, a SWOT analysis is employed to analyse the prospect of Islamic pawnbroking in future with possible recommendations that could be considered by the government, pawnbrokers, and the customers as well.
The findings from the surveys analysis demonstrate that the customers of Islamic pawnshops attest the positive role of pawnshop in both economic and social aspects of their lives especially in the case of low-income groups as compared to the conventional pawnshops. On the other hand, the results from the pawnbrokers’ analysis revealed that Islamic pawnbrokers demonstrated a promising prospect of the pawnshops’ business as compared to the conventional pawnbrokers as the latter operates with profit maximization and neglect the social welfare of the customer. Importantly, while the findings of the study renders valuable information in terms of behavioural dimension and customer preferences in pawnbroking, the findings are also useful for the businesses and government in considering the future development related to ar-rahn shops
Exclusive electroproduction of rho0 and J / psi mesons at HERA
No full textExclusive production of rho(0) and J/psi mesons in e(+)p collisions has been studied with the ZEUS detector in the kinematic range 0.25 < Q(2) < 50 GeV2, 20 < W < 167 GeV for the rho(0) data and 2 < Q(2) < 40 GeV2, 50 < IS' < 150 GeV for the J/psi data. Cross sections for exclusive rho(0) and J/psi, production have been measured as a function of Q2, W and t. The spin-density matrix elements r(00)(04), r(1-1)(1) and Rer(10)(5) have been determined for exclusive rho(0) production as well as r(00)(04) and r(1-1)(04) for exclusive J/psi production. The results are discussed in the context of theoretical models invoking soft and hard phenomena
Parameter-induced uncertainty quantification of soil N₂O, NO and CO₂ emission from Höglwald spruce forest (Germany) using the LandscapeDNDC model
No full textAssessing the uncertainties of simulation results of ecological models is becoming increasingly important, specifically if these models are used to estimate greenhouse gas emissions on site to regional/national levels. Four general sources of uncertainty effect the outcome of process-based models: (i) uncertainty of information used to initialise and drive the model, (ii) uncertainty of model parameters describing specific ecosystem processes, (iii) uncertainty of the model structure, and (iv) accurateness of measurements (e.g., soil-atmosphere greenhouse gas exchange) which are used for model testing and development.
The aim of our study was to assess the simulation uncertainty of the process-based biogeochemical model LandscapeDNDC. For this we set up a Bayesian framework using a Markov Chain Monte Carlo (MCMC) method, to estimate the joint model parameter distribution. Data for model testing, parameter estimation and uncertainty assessment were taken from observations of soil fluxes of nitrous oxide (N2O), nitric oxide (NO) and carbon dioxide (CO2) as observed over a 10 yr period at the spruce site of the Höglwald Forest, Germany. By running four independent Markov Chains in parallel with identical properties (except for the parameter start values), an objective criteria for chain convergence developed by Gelman et al. (2003) could be used.
Our approach shows that by means of the joint parameter distribution, we were able not only to limit the parameter space and specify the probability of parameter values, but also to assess the complex dependencies among model parameters used for simulating soil C and N trace gas emissions. This helped to improve the understanding of the behaviour of the complex LandscapeDNDC model while simulating soil C and N turnover processes and associated C and N soil-atmosphere exchange. In a final step the parameter distribution of the most sensitive parameters determining soil-atmosphere C and N exchange were used to obtain the parameter-induced uncertainty of simulated N2O, NO and CO2 emissions. These were compared to observational data of an calibration set (6 yr) and an independent validation set of 4 yr. The comparison showed that most of the annual observed trace gas emissions were in the range of simulated values and were predicted with a high certainty (Root-mean-squared error (RMSE) NO: 2.4 to 18.95 g N ha−1 d−1, N2O: 0.14 to 21.12 g N ha−1 d−1, CO2: 5.4 to 11.9 kg C ha−1 d−1). However, LandscapeDNDC simulations were sometimes still limited to accurately predict observed seasonal variations in fluxes
Revue d'histoire de la culture matérielle #49
No full textEditorial -- Articles: Razors, Shaving and Gender Construction: An Inquiry into the Material Culture of Shaving by G. Bruce Retallack -- Painting Without Permission: An Ethnographic Study of Hip-Hop Grafitti Culture by Janice Rahn -- Centres of 'Home-Like Influence': Residences for Women at the University of Toronto by Alyson E. King -- A Shocking Business: The Technology and Practice of Electrotherapeutics in Canada, 1840s to 1940s by J. T. H. Connor and Felicity Pope -- Exhibit Review: The Bata Shoe Museum, Toronto by Wendy Cooper -- Book Reviews -- Contributors.The Material History Bulletin was published 1976-Fall 1990 (nos. 1-32). The name was then changed to the Material History Review, published Spring 1991-Fall 2005 (nos. 33-62). The name changed again to Material Culture Review, Spring 2006 (no. 63)-present. Published semiannually
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