bluuebunny/crossref_metadata_2025 huggingface dataset:
Reservoir Crude Oil Viscosity Estimation From Wireline NMR Measurements - Rajasthan, India
Authors: Zittel R. J. , Beliveau D. , O'Sullivan T. , Mohanty R. , Miles J.
Published: July 2008

In 2004, the Mangala, Aishwariya, and Bhagyam fields were discovered in Rajasthan, India. In these high-permeability paraffinic reservoirs, viscosity is one of the main factors controlling performance. Pressure, volume, and temperature (PVT) data show areal and vertical variations in crude properties. Meter-by-meter geo-chemical core analyses corroborate vertical variations in oil composition. Continuous wireline measurements of nuclear magnetic resonance (NMR) properties and station NMR properties from wells drilled with both water-based muds (WBM) and synthetic oil-based muds (OBM) were also used to calculate a viscosity profile. This paper correlates results from all techniques and shows how NMR measurements can provide oil viscosity profiles in com-positionally complex pools.

Black-oil PVT samples typically test several meters of reservoir, while Rajasthan geochemical data are available at meter scale. NMR logs provide continuous data, and calibrated to PVT and geochemistry, they can provide the most detailed picture of in-situ viscosity variations.

Results were used to construct a detailed spatial description of the reservoir's in-situ oil viscosity. The NMR data helped to define a zone of biodegraded oil up to ∼25 m thick above the oil-water contact (OWC) and showed thin accumulations of higher-viscosity oil on top of minor shale layers within oil columns. The major conclusion is that detailed in-situ oil viscosity profiles can be developed from conventional wireline T2 measurements.
Modeling the Effect of Viscosity Ratio on Spontaneous Imbibition
Authors: Fischer Herbert , Wo Shaochang , Morrow Norman R.
Published: July 2008

Spontaneous-imbibition data for Berea sandstone cores, which are very strongly wetted by the aqueous phase and initially 100% saturated with mineral oil, are reported for linear, radial, and allfaces-open boundary conditions. Oil viscosities were 4, 63, and 173 cp, and aqueous-phase viscosities ranged from 1 to 495 cp. Oil-/aqueous-phase-viscosity ratios were varied by more than four orders of magnitude (0.01 to 173.1). Near-linear relationships (with slopes close to one-half), between the frontal position and imbibition time on a log-log scale, were obtained for both linear and radial countercurrent flow. Behavior is consistent, with near piston-like displacement by the imbibing aqueous phase. The results are analyzed by a new mathematical model that accounts for countercurrent spontaneous imbibition with symmetrical flow patterns. The model assumes that saturation and permeabilities to counterflowing phases behind the front are constant and that any effect of local change in interfacial curvature with distance is negligible. The results from the model are used to extend scaling to include the measured effect of viscosity ratio for linear and radial flow. For the all-faces-open boundary condition, commonly used in core-analysis studies, oil recovery vs. imbibition time is estimated by a combination of spherical and radial flow. Consistently close agreement was obtained between experiments and behavior predicted by the model.
Success Story of a Waterflood Project in a Geologically Complex, High-Viscosity Oil Reservoir in a Major Brownfield in South Oman
Authors: Choudhuri Biswajit , Al-Rawahi Mahir S.
Published: July 2008

This paper presents the success story of waterflooding in a geologically complex reservoir that contains high-viscosity (90 cp) oil. This reservoir is part of a large brownfield in south Oman and has been on production for more than 25 years. The reservoir comprises glacial sandstones of Palaeozoic age and is highly heterogeneous, with wide variation in reservoir characteristics at scales smaller than well spacing. The reservoir geology is complicated because of the presence of faults and fractures.

The reservoir has been subdivided into different areas that we call "catchments," characterized by their geological setting and dynamic reservoir behavior. Full-field water injection was started in the field after approximately 18 years of primary depletion. Different water-injection philosophies for different areas of the field have been adopted with consideration to factors such as primary drive mechanism operative in the reservoir, presence or absence of vertical-flow barriers; pre-existing field-development pattern; and more importantly, future development beyond waterflood to maximize the value of the reservoir in its entire life cycle.

The paper illustrates that the success of a waterflood in a complex reservoir relies on the implementation of a tailor-made development plan with flexibility to be changed on the basis of data from reservoir surveillance. The importance of well and reservoir management (WRM) to improve the value of waterflood is emphasized.
Controlling Water Production Using Gelled Polymer Systems
Authors: Willhite G. P. , Pancake R. E.
Published: July 2008

Arbuckle reservoirs in central Kansas produce by natural water-drive. Although clean oil is usually produced on initial completion of a well, the water cut increases with time. Water cuts of 99% and water production rates of 400 to 3,000 B/D are common. Wells cannot be pumped off. Water production has been reduced selectively by treating wells with a chrome acetate-polyacrylamide gelant. In most cases, incremental oil is produced following the treatment. This paper describes results from a seven-well program in which production wells were treated with chrome acetate-polyacrylamide gelant. Pressure data were obtained before the treatment, during the gel treatment and after gel treatment. Buildup data were interpreted to estimate kh before the treatment, and the extent of permeability reduction to oil and water caused by the treatment. Bottomhole-pressure (BHP) data obtained during the treatment provided were used to monitor gelant placement. Production data following the treatments were analyzed to determine incremental oil production and correlate the treatments to the production response. Water-production rates were reduced in every well, and reductions were persistent during intervals ranging from 7 to 36 months. Incremental oil was produced in four of seven wells treated in the program. The amount of incremental oil increased with volume of gelant injected in wells with openhole completions. Results of this test program suggest how to distinguish wells that are likely to take large treatments from those that can be treated only with small amounts of gelant. These results should improve treatment design and identify wells that are good candidates for successful treatment.
A Semianalytic Model for the Productivity Testing of Multiple Wells
Authors: Fokker Peter A. , Verga Francesca
Published: July 2008

We present a semianalytic method for modeling the productivity testing of vertical, horizontal, slanted, or multilateral wells. The method is applicable to both oil and gas reservoirs and automatically accounts for well interference. The use of analytic expressions ensures that short-time transient behavior and long-time semisteady-state behavior are handled appropriately, whether close to the well or further into the reservoir. Calculation times are still very limited—on the order of a few minutes to a few seconds when all wells are vertical. This makes the tool suitable for evaluating well testing and determining well productivity.

We based the approach on an earlier derived productivity prediction tool, in which the steady-state equations were solved. It has now been extended to solve the time-dependent diffusion equation. In our current method, the equations have first been transformed using the Laplace transformation. The expressions for the producing wells are combined with auxiliary sources outside the reservoir. The crux of the semianalytic method involves an adjustment of the positions and strengths of these sources in order to approximate the boundary conditions at the reservoir boundaries. The solution obtained is transformed back into the time domain by use of a Stehfest algorithm.

The new approach has been validated with numeric tools, including both reservoir simulators and well-test interpretation software. Validations were performed with artificial cases and with field production data, using both single-well and multiple-well production tests. The results of these tests were excellent.
A Survey of North Sea Enhanced-Oil-Recovery Projects Initiated During the Years 1975 to 2005
Authors: Awan A. R. , Teigland R. , Kleppe J.
Published: July 2008

This paper provides a summary and a guide of the enhanced-oil-recovery (EOR) technologies initiated in the North Sea in the period from 1975 until beginning of 2005. The five EOR technologies that have been initiated in this region are hydrocarbon (HC) miscible gas injection, water-alternating-gas (WAG) injection injection, simultaneous water-and-gas (SWAG) injection, foam-assisted WAG (FAWAG) injection, and microbial EOR (MEOR). Each EOR technology that has been initiated in the North Sea was identified with its respective maturity level and/or maturation time frame, technology use restrictions, and process efficiency on the basis of incremental oil.

Apart from WAG at Ekofisk and FAWAG at Snorre central fault block (CFB), all technologies have been applied successfully (i.e., positive in economic terms) to the associated fields. HC miscible gas injection and WAG injection can be considered mature technologies in the North Sea. The most commonly used EOR technology in the North Sea has been WAG, and it is recognized as the most successful EOR technology.

The main problems experienced were injectivity (WAG, SWAG, and FAWAG projects), injection system monitoring, and reservoir heterogeneities (HC miscible gas injection, WAG, SWAG, and FAWAG projects). Approximately 63% of all the reported EOR field applications have been initiated on the Norwegian continental shelf (NCS), 32% on the UK continental shelf, and the remainder on the Danish continental shelf. Statoil has been the leader in conducting EOR field applications in the North Sea. The majority of future research will concentrate on microbial processes, CO2 injection, and WAG (including SWAG) injection schemes.

In this review, laboratory techniques, global statistics, simulation tools, and economical evaluation were not considered and are considered outside of the scope of this paper.
The use of tritium content as an indicator of the groundwater contamination by sanitary landfills leachates in the region of Belo Horizonte City, Brazil
Authors: Bandeira J. V. , Mingote R. M. , Baptista M. B. , Oliveira D. M. , Lima F. P.
Published: July 2008

Tritium content in the leachate of sanitary landfills, in concentrations well above those observed in global precipitation, can be used as a tracer for the evaluation of the contamination of groundwater in piezometers of the landfills and in neighbouring tubular wells. This possibility was first investigated in Brazil for sanitary landfills in the region of Belo Horizonte City. Tritium levels together with the content of metals present in water and the measurement of soil electrical conductivity, proved to be valuable for these studies and also as a tracer for hydrodynamic studies of the surface water in the Ressaca creek.
Practical application of wastewater reuse in tourist resorts
Authors: Antakyalı D. , Krampe J. , Steinmetz H.
Published: July 2008

A medium-scale membrane bioreactor was tested in a large tourist resort on the south-western coast of Turkey with the treated wastewater subsequently being used for irrigational purposes. The wastewater treatment system was designed to eliminate carbonaceous and nitrogenous substances. Treatment efficiency was monitored by means of regular chemical and microbiological analyses. Information was collected on water use at different locations of the hotel. Specific values based on the number of guests were determined. Wastewater streams from kitchen, laundry and rooms were analysed to investigate the various contribution from these points. The social acceptance of the guests concerning the on-site wastewater treatment and reuse in the hotel was analysed using a questionnaire. The investigations indicated that the treated wastewater provides the required chemical and hygienic conditions to satisfy requirement for its reuse in irrigation. The acceptance by guests was encouraging for such applications.
Nitrogen loading on groundwater from the discharge of on-site domestic wastewater effluent into different subsoils in Ireland
Authors: Gill L. W. , O'Suilleabhain C. , Misstear B. D. R. , Johnston P. , Patel T. , O'Luanaigh N.
Published: July 2008

The performance of six separate percolation areas has been intensively monitored to ascertain the attenuation effects of the unsaturated subsoil with respect to on-site wastewater effluent. Septic tank effluent on three sites and secondary treated effluent on the other three sites was discharged into subsoils of varying percolation values. Samples of the percolating effluent were taken using suction lysimeters installed to nominal depths of 0.3, 0.6 and 1.0 m below the invert of the percolation trenches. The results clearly showed that the development of a biomat across the percolation areas receiving secondary treated effluent was muted on these sites compared to the sites receiving septic tank effluent. Significant differences were found between the sites receiving septic tank and secondary treated effluent in terms of the potential nitrogen loading to groundwater. The average nitrogen loading after 1.0 m depth of unsaturated subsoil per capita equated to 5.5, 3.3 and 3.2 gTotal-N/d for the sites receiving secondary treated effluent compared to 4.2, 1.7 and 0.3 gTotal-N/d for the sites receiving septic tank effluent. The noticeably higher nitrogen loading on one of the septic tank sites corresponded to the effluent percolating through highly permeable subsoil that counteracted any significant denitrification.
Recovery oriented phosphorus adsorption process in decentralized advanced Johkasou
Authors: Ebie Y. , Kondo T. , Kadoya N. , Mouri M. , Maruyama O. , Noritake S. , Inamori Y. , Xu K.
Published: July 2008

Decentralized advanced wastewater treatment using adsorption and desorption process for recovery and recycling oriented phosphorus removal was developed. Adsorbent particles made of zirconium were set in a column, and it was installed as subsequent stage of BOD and nitrogen removal type Johkasou, a household domestic wastewater treatment facility. The water quality of the effluent of adsorption column in a number of experimental sites was monitored. The effluent phosphorus concentration was kept below 1 mg l−1 during 90 days at all the sites. Furthermore, over 80% of the sites achieved 1 mg l−1 of T-P during 200 days. This adsorbent was durable, and deterioration of the particles was not observed over a long duration. The adsorbent collected from each site was immersed in alkali solution to desorb phosphorus. Then the adsorbent was reactivated by soaking in acid solution. The reactivated adsorbent was reused and showed almost the same phosphorus adsorption capacity as a new one. Meanwhile, the desorbed phosphorus was recovered with high purity as trisodium phosphate by crystallization. It is proposed as a new decentralized system for recycling phosphorus that paves the way to high-purity recovery of finite phosphorus.
Degradation of macromolecular tannic acid by O3/H2O2
Authors: Ji-min S. , Xue-yan L. , Zhong-lin C. , Xiao-hong G. , Xue Z. , Zhen-zhen X.
Published: July 2008

Tannic acid, being polyhydroxyl, is a macromolecule natural organic matter. The efficiency and mechanism of degradation of tannic acid by O3 and O3/H2O2 was studied. The results showed that the addition of H2O2 had no obvious improvement on the ozonation efficiency of tannin. It was observed that the addition of H2O2 decreased the removal efficiency of TOC by 10%. The relative intensity of ∙OH generated in the O3-H2O2 system was detected by electronic spin resonance (ESR) and it was found that tannin consumed the ∙OH radicals, which may be associated with the polyhydroxyl structure of tannin. Derived with PFBBr and analysed by GC-ECD, the by-products of tannin ozonation were found to be aldehydes such as acetaldehyde, glyoxal and methyl glyoxal. Analysis with an ion chromatogram showed that the final products of tannin were oxalic acid, ketomalonic acid and oxalic acid, which consisted of 35% of TOC in both systems.
Use of comprehensive two-dimensional gas chromatography for the broad screening of hazardous contaminants in urban wastewaters
Authors: Semard Gaëlle , Bruchet Auguste , Cardinaël Pascal , Bouillon Jean-Philippe
Published: July 2008

The list of priority chemicals included in various regulations such as the European Water Framework Directive, as well as the list of hazardous contaminants identified in the aquatic environment, are increasing at an accelerated pace. Therefore, there is a need for broad spectrum methods capable of simultaneously determining hundreds, if not thousands, of contaminants. For the analysis of non-polar or semi-polar contaminants, comprehensive two-dimensional gas chromatography (GC × GC) is more powerful than conventional gas chromatography thanks to a separation on two different stationary phases. This paper reports the use of GC × GC for a broad screening of hazardous contaminants in an urban wastewater plant. Comparison between the raw and treated wastewater has been carried out using a semi-quantitative approach. A variety of drugs, personal care products, pesticides, carcinogens and compounds toxic for reproduction, were identified. Most of these compounds were removed or decreased by this wastewater treatment plant. Preliminary results from this single plant will need to be confirmed by a more extensive study before drawing conclusions on the removal efficiency of 2D-GC amenable compounds.
Semi-quantitative analysis of a specific database on priority and emerging substances in wastewater and sludge
Authors: Ruel S. Martin , Choubert J. M. , Ginestet P. , Coquery M.
Published: July 2008

The Water Framework Directive (WFD) has drawn attention to a series of metals and organic compounds because of their demonstrated or potential harmfulness for aquatic environments. The aim of our work was to build and to process a “practical” database focused on the role of wastewater treatment plants for the removal of the 37 priority compounds that have to be reduced or stopped by 2015, and of 34 additional relevant contaminants. About 11,000 concentration values in raw and treated wastewater and sludge, from more than 100 peer-reviewed articles and six French national screening programs, were integrated. A systematic approach showed the global low quality of data for most of the compounds, with missing information about the treatment process, sampling and analysis, leading to 10% of the data available for removal efficiency calculations. A semi-quantitative analysis allowed the identification of 20 priority and 10 additional relevant substances more frequently quantified at significant concentrations in raw wastewater and treated wastewater. Conventional activated sludge was able to remove more than 70% of half of the studied compounds, leaving only 10% of them with less than 50% removal. Physical–chemical treatments appeared to be about 30% less efficient than biological treatments. In addition, very few data are available concerning some compounds and some processes, especially sludge treatment and tertiary wastewater treatment processes. Therefore, complementary on-site measurements and modeling are required to propose adapted solutions for the treatment of priority and emerging substances in wastewater treatment plants.
Multicriteria Evaluation of Wildlife Management Units in Campeche, Mexico
Authors: GARCÍA‐MARMOLEJO GABRIELA , ESCALONA‐SEGURA GRISELDA , VAN DER WAL HANS
Published: July 2008

Abstract: Since 1997 the Mexican government has promoted Management Units for Conservation and Sustainable Use of Wildlife (UMAs) on private and community lands as an economically attractive mean for the conservation of biodiversity. To date, compliance of UMAs with stated sustainability goals has not been evaluated. Thus, we designed multicriteria evaluation framework based on the stated objectives of the national UMA program and applied it to a sample of 6 UMAs operating in peasant communities near or in the Calakmul Biosphere Reserve in Campeche, Mexico. Evaluation criteria covered thematic areas of environment, economy, social development, and laws and rules. We formulated 15 criteria with 29 indicators, and 133 verifiers. Data for the verifiers were based on direct observation, interviews with key actors in the peasant communities, participation in regional meetings, scrutiny of government reports, and databases. We calculated sustainability indexes by weighting, summing, and standardizing verifiers to percentage scales, and aggregating to the successive higher hierarchical levels of the evaluation framework. We found an average overall sustainability index of 45.7% for the UMAs evaluated. Scores were highest for the environment thematic area (55.2%), followed by economy (43.4%), social development (42.3%), and laws and rules (41.7%). We observed particularly low indicators for management strategies, habitat monitoring, environmental education, and knowledge of wildlife laws. We conclude that the contribution of UMAs to the conservation and sustainable use of biodiversity could be improved by a number of actions. These include developing wildlife management educational programs with a strong environmental legislation component, the correct enforcement of wildlife laws, and creating country‐wise links among academic and governmental institutions promoting the work with regional and national wildlife experts.
Abundance Estimation With a Transient Model Under the Robust Design
Authors: CLAVEL JOANNE , ROBERT ALEXANDRE , DEVICTOR VINCENT , JULLIARD ROMAIN
Published: July 2008

Abstract: A common situation in capture‐mark‐recapture (CMR) studies on birds and other organisms is to capture individuals not belonging to the studied population only present during the short time of the capture session. Presence of such transient individuals affects demographic parameter estimation from CMR data. Methods exist to reduce biases on survival estimates in the presence of transients and have been shown to be particularly efficient within the Robust Design framework (several secondary capture sessions within a short time interval during which the studied population can be assumed closed). We present a new model to estimate population size accounting for transients. We first used simulated data to show that the method reduces positive biases due to transients. In a second step, we applied the method to a real CMR dataset on a reed warbler (Acrocephalus scirpaceus) population. Population size estimates are reduced by up to 50% when correcting for the presence of transients. Many field studies on managed animal populations use capture‐recapture methodology to obtain crucial parameters of the focal population demography. The resulting data sets are used either to estimate population size ignoring the presence of transients, or to estimate vital rates, accounting for transients but overlooking abundance estimation. Our method conciliates these 2 approaches.
Field Use of Isoflurane for Safe Squirrel and Woodrat Anesthesia
Authors: PARKER WILLIAM T. , MULLER LISA I. , GERHARDT REID R. , O'ROURKE DORCAS P. , RAMSAY EDWARD C.
Published: July 2008

Abstract: We evaluated a chamber and nose cone method of isoflurane delivery for anesthetizing eastern gray squirrels (Sciurus carolinensis; summer n = 43, winter n = 48) and Allegheny woodrats (Neotoma magister; summer n = 24, winter n = 13) for use when pain or stress was possible from sampling procedures. Mean induction time for squirrels (from beginning of isoflurane administration to safe removal from trap), was 4.63 ± 0.58 minutes. Squirrels awoke more quickly in summer (1.40 ± 0.15 min) than in winter (3.62 ± 0.24 min) after removal of the nose cone. We manually restrained woodrats and administered the nose cone for 0.5 minutes to each animal. Woodrats awoke after 4.76 ± 0.58 minutes following the final dose of isoflurane for both seasons. These methods are useful for working with small mammals in the field and provide an appropriate anesthetic when there may be more than slight pain or distress.
Estimating Sustainable Harvest in Wolverine Populations Using Logistic Regression
Authors: DALERUM FREDRIK , SHULTS BRAD , KUNKEL KYRAN
Published: July 2008

Abstract: Population viability analysis (PVA) is a common tool to evaluate population vulnerability. However, most techniques require reliable estimates of underlying population parameters, which are often difficult to obtain and PVA are, therefore, best used in a qualitative context. Logistic regression is a powerful alternative to traditional PVA methods but has received surprisingly limited attention. Logistic regression fits regression equations to binary output from PVA models at a specific point in time to predict probability of a binary response over a range of parameter values. We used logistic regression on output from stochastic population models to evaluate the relative importance of demographic parameters for wolverine (Gulo gulo) populations and to estimate sustainable harvest in a wolverine population in Alaska. Our analysis indicated that adult survival is the most important demographic parameter to reliably estimate in wolverine populations because it had a greater effect on population persistence than did both fecundity and subadult survival. In accordance with this, harvest rate had a greater effect on population persistence than did any of the other harvest‐ and migration‐related variables we tested. Furthermore, a high proportion of harvested females strengthened the effect of harvest. Hypothetical wolverine populations suffered high probabilities of both extinction and population decline over a range of realistic population sizes and harvest regimes. We suggest that harvested wolverine populations must be regarded as sink populations and that source populations in combination with sufficient dispersal corridors must be secured for any wolverine harvest to be sustainable.
Effects of Season and Scale on Response of Elk and Mule Deer to Habitat Manipulation
Authors: LONG RYAN A. , RACHLOW JANET L. , KIE JOHN G.
Published: July 2008

Abstract:Manipulation of forest habitat via mechanical thinning or prescribed fire has become increasingly common across western North America. Nevertheless, empirical research on effects of those activities on wildlife is limited, although prescribed fire in particular often is assumed to benefit large herbivores. We evaluated effects of season and spatial scale on response of Rocky Mountain elk (Cervus elaphus) and mule deer (Odocoileus hemionus) to experimental habitat manipulation at the Starkey Experimental Forest and Range in northeastern Oregon, USA. From 2001 to 2003, 26 densely stocked stands of true fir (Abies spp.) and Douglas‐fir (Pseudotsuga menziesii) were thinned and burned whereas 27 similar stands were left untreated to serve as experimental controls. We used location data for elk and mule deer collected during spring (1 Apr‐14 Jun) and summer (15 Jun‐31 Aug) of 1999–2006 to compare use of treated and untreated stands and to model effects of environmental covariates on use of treated stands. In spring, elk selected burned stands and avoided control stands within the study area (second‐order selection; large scale). Within home ranges (third‐order selection; small scale), however, elk did not exhibit selection. In addition, selection of treatment stands by elk in spring was not strongly related to environmental covariates. Conversely, in summer elk selected control stands and either avoided or used burned stands proportional to their availability at the large scale; patterns of space use within home ranges were similar to those observed in spring. Use of treatment stands by elk in summer was related to topography, proximity to roads, stand size and shape, and presence of cattle, and a model of stand use explained 50% of variation in selection ratios. Patterns of stand use by mule deer did not change following habitat manipulation, and mule deer avoided or used all stand types proportional to their availability across seasons and scales. In systems similar to Starkey, manipulating forest habitat with prescribed fire might be of greater benefit to elk than mule deer where these species are sympatric, and thus maintaining a mixture of burned and unburned (late successional) habitat might provide better long‐term foraging opportunities for both species than would burning a large proportion of a landscape.
Fuel‐Reduction Treatment Effects on Avian Community Structure and Diversity
Authors: HURTEAU SARAH R. , SISK THOMAS D. , BLOCK WILLIAM M. , DICKSON BRETT G.
Published: July 2008

Abstract:We assessed responses of the breeding bird community to mechanical thinning and prescribed surface fire, alone and in combination, between 2000 and 2006 in ponderosa pine (Pinus ponderosa) forests in northern Arizona, USA. Fuel‐reduction treatments did not affect species richness or evenness, and effects on density of 5 commonly detected species varied among species. Populations of some species, such as the western bluebird (Sialia mexicana), increased following burning treatments, whereas others, such as the mountain chickadee (Poecile gambeli), decreased in response to thinning treatments. Our results also identified a temporal response component, where avian community composition and structure changed synchronously on all treatments over time. Given the modest effects these small‐scale fuel‐reduction treatments had on avian composition and the specific density responses of particular species, our results suggest that land managers should consider implementing prescribed surface fire after thinning projects, where appropriate.
Influence of Landscape Composition and Structure on Antler Size of White‐Tailed Deer
Authors: STRICKLAND BRONSON K. , DEMARAIS STEPHEN
Published: July 2008

Abstract: Cause for spatial variation in phenotypic quality of white‐tailed deer (Odocoileus virginianus) populations is of great interest to wildlife managers. Relating phenotypic variation of populations to large‐scale land‐use patterns may provide insight into why populations exhibit spatial variation and elucidate how management can influence population phenotype. We used an information‐theoretic approach to relate average antler size of 203 deer populations to composition and structure of the habitat occupied by those populations. We used interspersion, edge, and diversity indices to represent habitat structure and percentage of area in vegetation types to represent habitat composition. Landscape composition was a better predictor of deer population antler size than was landscape structure. Percentages of the management unit in agriculture, pasture, and pine forest were variables commonly found in the region‐specific set of best models. Model‐averaged estimates of agriculture and pasture parameters were always positive and estimates of pine forest parameters were always negative, which suggests that land‐use types that promote growth of early successional herbaceous plants will positively influence antler size and, most likely, body growth and reproduction of white‐tailed deer populations. Conversely, our findings suggest landscapes dominated by pine forests did not provide optimal amounts of quality forages for white‐tailed deer. Pine forest effects should be mitigated using a combination of increased harvest to lower deer density and silvicultural practices like thinning, prescribed burning, and selective herbicide applications that stimulate growth of high‐quality forages beneath the forest canopy to improve deer phenotypic quality.
Exploring Migration Data Using Interval‐Censored Time‐to‐Event Models
Authors: FIEBERG JOHN , DELGIUDICE GLENN
Published: July 2008

Abstract:Ecologists and wildlife biologists rely on periodic observation of radiocollared animals to study habitat use, survival, movement, and migration, resulting in response times (e.g., mortality and migration) known only to occur within an interval of time. We illustrate methods for analyzing interval‐censored data using data on the timing of fall migration (from spring‐summer‐fall to winter ranges) for white‐tailed deer (Odocoileus virginianus) in northern Minnesota, USA, during years 1991–1992 to 2005–2006. We compare both nonparametric and parametric methods for estimating the cumulative distribution function of migration times, and we suggest a parametric (cure rate) model that accounts for conditional (facultative) migrators as a potential alternative to traditional parametric models. Lastly, we illustrate methods for exploring the effect of environmental covariates on migration timing. Models with time‐dependent covariates (snow depth, temp) were sensitive to the treatment of the data (as interval‐censored or known event times), suggesting the need to account for interval‐censoring when modeling the effect of these covariates.
Chiral Metal Surfaces and Nanoparticles
Authors: Gautier Cyrille , Bürgi Thomas
Published: July 2008

The surface of metals can exhibit intrinsic chiral structure. Furthermore, chirality can be bestowed onto achiral metal surfaces by adsorption of chiral molecules. Such chiral metal surfaces are promising as heterogeneous enantioselective catalysts and may furthermore be used for the
separation and detection of enantiomers. Similarly, metal nanoparticles can be chiral, which is reflected by their optical activity in metal-based electronic transitions. The transfer of chirality from adsorbate to the metal surface depends on the structure of the former, which is however
difficult to elucidate. It is shown that vibrational circular dichroism can be used to determine the structure of a chiral adsorbed molecule and the way it interacts with the metal.
Catalytic Methods for Direct Access to Chiral High-Added-Value Products
Authors: Peters René , Fischer Daniel F. , Jautze Sascha , Koch Florian M. , Kull Thomas , Tiseni Paolo S. , Xin Zhuo-Qun , Zajac Marian
Published: July 2008

This account summarizes the activities of the first three years of our young research group working in the field of homogeneous asymmetric catalysis.
The Role of Architecture in Society: Structuring of the Family Unit among Moorish Pastoral Nomads of Mauritania
Authors: Boulay Sébastien
Published: July 2008

This paper sheds new light on the existence of a multitude of architectural concepts amongst Moorish nomadic herders of Western Sahara. The description and the analysis of its three variations help us to better understand the nuclear family's genesis in this society and the important role of architectures and, more generally, of objects in this process. In the Mauritanian nomadic society, the type of habitation most used and the best known is the tent, the khayma.1 Its most likely heritage is from the progressive arrival of Arab Bedouin tribes into the Western Sahara regions starting in the thirteenth and fourteenth centuries AD. (Feilberg 1944). It consists of a rectangular cloth about 7 m by 6 m, made up of strips woven from black wool and the hair of camels (often replaced today by strips of imported cotton cloth) and supported at the centre by the crossing of two long slanted wooden poles, giving the whole a pointed and pyramidal form. The khayma is at the base of the strong metonymical relationship with the family living there,2 benefiting from a privileged status in the Moor's system of representations and in their contemporary identity among the Bedouins and the rest of the population (Boulay 2004). Nevertheless, on-site investigations have allowed us to discover that the khayma is not the only kind of tent used by pastoral Mauritanians.3 There is, in effect, another type, or more precisely another architectural concept, less known and named the benye. This feminine noun, based on the Arab root BNY, expresses the idea of 'build', 'erect' or 'construct'4 and takes the form not of the two long slanted poles of the khayma but rather is based on arcs or stakes placed vertically. Through a careful examination of the three current uses of the word benye - 'secret' shelter of a young couple, double roof 'discreet' of the black tent, light structure for long migrations - we will see how the study of this architectural concept can instruct us regarding the process of forming the marital couple and family in a Muslim society. We will also better understand how, even today, this contributes to the confidentiality and marginality of this important factor and its different known materials in this part of the Western Sahara.
The Economics of Mobile Pastoralism: A Global Summary
Authors: Davies Jonathan , Hatfield Richard
Published: July 2008

The World Initiative for Sustainable Pastoralism (WISP) recently commissioned a series of reviews on the economics of pastoralism. Eight regional desk studies were conducted: (1) Southern Africa and the Horn, (2) West Africa, (3) East Africa, (4) North Africa, (5) South America, (6) Asia, (7) the Middle East, and (8) Europe. The studies sought to identify the contribution of pastoralism to domestic and global markets, by gathering productivity indicators and market behaviour, and identifying indirect values and methodologies for analysing indirect values. This review is intended to add to the global understanding on the importance of mobile pastoralism as a form of productive and sustainable land management. By gathering information, the review highlights existing knowledge on the value of pastoralism, gaps in this knowledge, trends in pastoral economies, and policy options that can support rangeland economies most effectively. Presented here is a summary of the main points relating to economic valuation of mobile pastoralism.
Small-scale spatio-temporal characteristics of accumulation rates in western Dronning Maud Land, Antarctica
Authors: Anschütz Helgard , Steinhage Daniel , Eisen Olaf , Oerter Hans , Horwath Martin , Ruth Urs
Published: July 2008

Spatio-temporal variations of the recently determined accumulation rate are investigated using ground-penetrating radar (GPR) measurements and firn-core studies. The study area is located on Ritscherflya in western Dronning Maud Land, Antarctica, at an elevation range 1400–1560 m. Accumulation rates are derived from internal reflection horizons (IRHs), tracked with GPR, which are connected to a dated firn core. GPR-derived internal layer depths show small relief along a 22 km profile on an ice flowline. Average accumulation rates are about 190 kg m−2 a−1 (1980–2005) with spatial variability (1σ) of 5% along the GPR profile. The interannual variability obtained from four dated firn cores is one order of magnitude higher, showing 1σ standard deviations around 30%. Mean temporal variations of GPRderived accumulation rates are of the same magnitude or even higher than spatial variations. Temporal differences between 1980–90 and 1990–2005, obtained from two dated IRHs along the GPR profile, indicate temporally non-stationary processes, linked to spatial variations. Comparison with similarly obtained accumulation data from another coastal area in central Dronning Maud Land confirms this observation. Our results contribute to understanding spatio-temporal variations of the accumulation processes, necessary for the validation of satellite data (e.g. altimetry studies and gravity missions such as Gravity Recovery and Climate Experiment (GRACE)).
Chronic Fatigue Syndrome: Implications for Women and their Health Care Providers During the Childbearing Years
Authors: Allen Peggy Rosati
Published: June 2008

Chronic fatigue syndrome is a complex debilitating medical disorder that affects approximately 4 million persons in the United States, predominantly women. There has been little scientific exploration about the experience of pregnancy, childbirth, and the postpartum period for women with this disorder. A review of the literature and current research findings addressing the epidemiology, diagnosis, symptoms, and treatment of chronic fatigue syndrome are presented, as well as the currently available data regarding the experience of women with chronic fatigue syndrome anticipating or experiencing pregnancy and the postpartum period. Expert opinion is presented along with current evidence to provide guidelines for the care of women with chronic fatigue syndrome during pregnancy, labor and birth, lactation, and the postpartum period.
Tests for screening olfactory and gustatory function in school‐age children
Authors: Laing David G. , Segovia C. , Fark T. , Laing O.N. , Jinks A.L. , Nikolaus J. , Hummel T.
Published: June 2008

Objective

Determine the suitability of three tests based on the identification of familiar odors and tastes for the clinical assessment of olfaction and gustation in children.

Study Design and Setting

A total of 232 children aged 5 to 7 years from Sydney public schools and 56 adults aged 18 to 51 years participated in a cross‐sectional study.

Results

The children demonstrated they can identify the majority of the 16 test odorants and 4 common tastes that describe gustatory function. The response distributions obtained for each test provide the basis for a set of normative data for young children.

Conclusion

Olfactory and gustatory function can be determined in school‐age children using the three tests described.

Significance

Currently no satisfactory clinical tests of olfaction and gustation for children or normative data are available. The present study resolves these shortcomings and provides normative data that can be used in the diagnosis of olfactory and gustatory impairment in school‐age children.
Polysomnographic outcome of adenotonsillectomy for obstructive sleep apnea in children under 5 years old
Authors: Walker Paul , Whitehead Bruce , Gulliver Tanya
Published: June 2008

Objective

To determine success rates after adenotonsillectomy for obstructive sleep apnea (OSA); postoperative polysomnogram (PSG) results were compared with preoperative results in children younger than 5 years.

Methods

Thirty‐four children with a preoperative respiratory disturbance index (RDI) greater than 5 in rapid eye movement (REM) sleep underwent both preoperative and postoperative PSG with at least five of seven parameters recorded.

Results

Preoperatively, mean total RDI was 15.5, mean REM RDI was 39.6, and 25 (74%) had severe OSA (REM RDI > 20). Postoperatively, mean total RDI improved to 3 (P > 0.001), mean REM RDI to 7.4 (P < 0.001), and 4 remained severe. Overall 22 (65%) showed REM RDI in the normal range (<5), including all with a preoperative REM RDI less than 30.

Conclusion

On PSG criteria, most children with OSA significantly improved after adenotonsillectomy, but a number had persisting abnormalities. Postoperative PSG should be considered to identify unresolved OSA.
Outcome of mobile ear surgery for chronic otitis media in remote areas
Authors: Homøe Preben , Siim Christian , Bretlau Poul
Published: June 2008

Objectives

The Inuit of Greenland, Canada and Alaska suffer from chronic otitis media (COM). In Greenland these patients used to be referred to Denmark for ear surgery. This was expensive and unsatisfactory, and the results were poor. A mobile ear surgery project was developed.

Design

The study is longitudinal and prospective with follow‐up.

Subjects and Methods

The 274 patients were selected according to severity of COM and hearing loss. Only air conduction (AC) audiometry was obtained. Median age was 27 years and 55% were females.

Results

Closure rates at three weeks, one year, and two years were 67 percent, 72 percent, and 76 percent, respectively. Median AC pure tone average improvement was 15 dB and 12 dB after one year and two years, and 73 percent and 67 percent were satisfied. Outcome was associated with quality of the surgical skills (P < 0.002). We found marked spontaneous fluctuations between the follow‐ups.

Conclusion

The results of mobile ear surgery in Greenland are acceptable. Mobile ear surgery may be implemented in areas with limited access to health care, eg, in developing countries.
Angioedema and angiotensin‐converting enzyme inhibitors: Are demographics a risk?
Authors: Mahoney Elizabeth J. , Devaiah Anand K.
Published: June 2008

Objectives

The use of angiotensin‐converting enzyme inhibitors (ACEI) has become the leading cause of acquired angioedema. Previous studies have suggested that certain patient populations may be at a higher risk for ACEI‐induced angioedema. The objective of this study was to evaluate any demographic associations.

Study Design

A retrospective chart review.

Materials and Methods

Angioedema patients from 1999 to 2004 treated at a tertiary care hospital were reviewed. Demographics, inciting factors, and comorbid conditions were examined.

Results

One hundred eighty‐two patients met inclusion criteria. Sixty‐three percent of patients with angioedema had ACEI triggers. Eighty‐one percent of all ACEI angioedema occurred in black patients. Of all angioedema patients, 70% (95% confidence interval [CI], 62%‐78%) of black patients noted an ACEI as the inciting agent compared with 44% (95% CI, 30%‐59%) in other patient groups. Black patients were 3.03 times more likely to have angioedema from an ACEI than all other patient groups (95% CI, 1.54‐5.94).

Conclusion

This study represents the largest series of patients with angioedema. Although retrospective in nature, the data show that black patients are at a higher risk for ACEI‐induced angioedema.
A New Approach for Determining Exchange-Rate Level Preferences
Authors: Walter Stefanie
Published: July 2008

In research on the political economy of exchange rates, a good understanding of who will endorse and who will oppose certain exchange-rate policies is central to understanding how actual exchange-rate policies are made and how the global exchange-rate system changes over time. Since existing classifications of exchange-rate level preferences have several shortcomings, this article proposes a new and more nuanced strategy for identifying preferences on exchange-rate valuation. This approach takes into account the complex interrelationship between exchange-rate and monetary policy, and the effects of these policies on balance sheets. In addition, the approach accounts for the dynamics of preference formation and change. Comparative case studies of currency crises in Hong Kong, South Korea, Thailand, and Taiwan show that considering actors' vulnerabilities to exchange-rate and interest-rate changes enhances understanding of their exchange-rate level preferences. The case studies also indicate that societal preferences affect policy outcomes. Exchange-rate stability was maintained in countries where private actors' vulnerabilities to depreciation were high. However, when pressure intensified, exchange rates were subsequently depreciated in countries where vulnerabilities to a monetary tightening exceeded the potential costs of depreciation.