142 results on '"Andersen, D."'
Search Results
2. A participatory and comprehensive intervention to improve violence prevention in two high-risk occupations: effect and process evaluation of a stepped wedge cluster randomised trial.
- Author
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Andersen, Lars Peter, Jaspers, S., Andersen, D., Karlsen, I., and Aust, B.
- Subjects
VIOLENCE prevention ,INDUSTRIAL hygiene ,PRISON personnel ,WEDGES ,THREATS of violence - Abstract
Background: Work-related violence committed by clients, patients, and customers represents a major occupational health risk for employees that needs to be reduced. Methods: We tested a comprehensive violence prevention intervention involving active participation of both employees and managers in the Prison and Probation Service (PPS) and on psychiatric wards in Denmark. We used a stepped wedge cluster randomised controlled trial design. We measured the degree of implementation of the intervention by registration of fidelity, reach, and dose and used a mixed-effects regression analysis to estimate the effects of the intervention. Results: We recruited 16 work units for the intervention, but three work units dropped out. The average implementation rate was 73%. In the psychiatric wards, the intervention led to statistically significant improvements in the primary outcome (an increase in the degree to which managers and employees continuously work on violence prevention practices based on their registration and experiences), but none statistically significant improvements in any of the secondary outcomes. In the PPS units, the intervention did not lead to a statistically significant improvement in the primary outcome, but to statistically significant improvements in three secondary outcomes. Conclusion: Most work units were able to carry out the intervention as planned. The intervention showed mixed results regarding the primary outcome. Nevertheless, the results indicate improvements also in the sector where a change in the primary outcome was not achieved. The results point at that a participatory and comprehensive approach could be a viable way of working with violence prevention in high-risk workplaces. Trial registration: ISRCTN86993466: 20/12/2017 [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
3. A participatory and comprehensive intervention to improve violence prevention in two high-risk occupations: effect and process evaluation of a stepped wedge cluster randomised trial.
- Author
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Andersen, Lars Peter, Jaspers, S., Andersen, D., Karlsen, I., and Aust, B.
- Subjects
VIOLENCE prevention ,INDUSTRIAL hygiene ,PRISON personnel ,WEDGES ,THREATS of violence - Abstract
Background: Work-related violence committed by clients, patients, and customers represents a major occupational health risk for employees that needs to be reduced. Methods: We tested a comprehensive violence prevention intervention involving active participation of both employees and managers in the Prison and Probation Service (PPS) and on psychiatric wards in Denmark. We used a stepped wedge cluster randomised controlled trial design. We measured the degree of implementation of the intervention by registration of fidelity, reach, and dose and used a mixed-effects regression analysis to estimate the effects of the intervention. Results: We recruited 16 work units for the intervention, but three work units dropped out. The average implementation rate was 73%. In the psychiatric wards, the intervention led to statistically significant improvements in the primary outcome (an increase in the degree to which managers and employees continuously work on violence prevention practices based on their registration and experiences), but none statistically significant improvements in any of the secondary outcomes. In the PPS units, the intervention did not lead to a statistically significant improvement in the primary outcome, but to statistically significant improvements in three secondary outcomes. Conclusion: Most work units were able to carry out the intervention as planned. The intervention showed mixed results regarding the primary outcome. Nevertheless, the results indicate improvements also in the sector where a change in the primary outcome was not achieved. The results point at that a participatory and comprehensive approach could be a viable way of working with violence prevention in high-risk workplaces. Trial registration: ISRCTN86993466: 20/12/2017 [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
4. Influence of landscape and connectivity on anuran conservation: population viability analyses to designate protected areas.
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Andersen, D., Jang, Y., and Borzée, A.
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PROTECTED areas ,BIOLOGICAL extinction ,POPULATION viability analysis ,ECOLOGICAL models ,HABITATS ,ENDANGERED species ,PREDATION - Abstract
Threatened species with restricted ranges are at risk from habitat fragmentation and loss, which amplifies genetic bottleneck and impacts of small changes to their environments. Ecological models including population viability analyses (PVAs) can predict the trajectory of populations in a way that is not invasive or detrimental to the study species. They can therefore be a vital tool in modeling populations for conservation purposes. Although habitat suitability models have been used in studies to suggest areas for protected area designation, PVAs are generally not used in this regard. Dryophytes suweonensis and Dryophytes flaviventris are two threatened treefrog species endemic to the Korean Peninsula. The two species face threats of habitat loss and degradation and predation by invasive species among others. We used an integrated modeling approach combining ecological niche, connectivity, and PVAs in Vortex to determine the likelihood of extinction of each species under baseline and protected area designation scenarios. Designation scenarios were simulated in Vortex through halting future reduction in carrying capacity (halting future degradation to sites through protected area status), reducing effects of catastrophes (mitigating the effects of drought), and reducing mortality rates (controlling invasive predator populations and ex situ raising of tadpoles to maturity). We classified the combination of these management efforts as "active management" as opposed to "no management," which is currently being practiced. We additionally used a stepwise approach to determine designation priority of individual patches. Under current conditions (no management), the resulting effective metapopulations after 100 years were 167 ± 325 individuals with an 86.5% extinction probability for D. suweonensis and 165 ± 200 individuals with a 90.3% extinction probability for D. flaviventris. Under active management of all sites (93 sites covering 426.9 km2), the extinction probability was 0% for both species with significantly increased metapopulation sizes, 15 910 ± 2855 for D. suweonensis, and 4400 ± 874 for D. flaviventris. Determining designation priority can inform the regulatory bodies on which habitat to designate and whether active or passive management should be applied. Without intervention, these species will be likely to face imminent extinction. In addition to being useful for government‐imposed conservation management, our study can be followed by future studies as a methodology for prioritizing sites for protected area designation. [ABSTRACT FROM AUTHOR]
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- 2023
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5. THE SOCIAL RELEASE PARADIGM: INVESTIGATIONS OF RESTRAINER AVERSION.
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Blystad, M. H., Asare, P., Andersen, D., and Johansen, E. B.
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OPERANT behavior ,AVERSION ,SOCIAL contact ,SOCIAL interaction ,PROSOCIAL behavior ,RESEARCH personnel - Abstract
Copyright of Mexican Journal of Behavioral Analysis / Revista Mexicana de Análisis de la Conducta is the property of Sociedad Mexicana de Analisis de la Conducta and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
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- 2023
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6. Development and validation of a minimally invasive and image-guided tape stripping method to sample atopic skin in children.
- Author
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Yélamos, O, Andersen, D, Pont, M, Iglesias, P, Potrony, M, Domínguez, M, Herrero, A, Alejo, B, Mateu, J, Røpke, M, Danneskiold-Samsøe, N B, Malvehy, J, Guy, R H, Brix, S, and Puig, S
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SKIN imaging ,OPTICAL coherence tomography ,ATOPIC dermatitis ,COMPLEMENTARY DNA ,CONFOCAL microscopy - Abstract
Background Molecular skin profiling techniques, typically performed on skin samples taken by punch biopsy, have enhanced the understanding of the pathophysiology of atopic dermatitis (AD), thereby enabling the development of novel targeted therapeutics. However, punch biopsies are not always feasible or desirable, and novel minimally invasive methods such as skin tape stripping have been developed. Aim To develop, optimize and validate a novel tape stripping method guided by noninvasive in vivo skin imaging to sample atopic skin in children. Methods Skin tape stripping-based procedures were compared and optimized using data from 30 healthy controls (HCs: 5 adults, 25 children) and 39 atopic children. Evaluations were guided by high-resolution photography, reflectance confocal microscopy, optical coherence tomography and transepidermal water loss measurements. We assessed and compared adverse events (AEs), the time needed to perform the sampling and the cDNA levels obtained from the tapes. Results Tape stripping methods based on previously described protocols resulted in erosions in all participants and required a median time of 65 min to perform (range 60–70 min), but provided good cDNA yield. Shorter durations appeared less invasive but provided lower cDNA yield. The final optimized tape stripping protocol, using 11 tapes of 22 mm in diameter, each applied twice for 5 s with 90° rotation, did not produce significant AEs, was completed within a median time of 7 min (range 5–15 min) and provided good cDNA yield both in HCs and atopic children. Conclusion Our minimally invasive method is safe and reliable, and provides reproducible acquisition of cDNA in atopic children. In addition, it enables rapid sample collection, a crucial factor in clinical practice. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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7. A Dilp8-dependent time window ensures tissue size adjustment in Drosophila.
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Blanco-Obregon, D., El Marzkioui, K., Brutscher, F., Kapoor, V., Valzania, L., Andersen, D. S., Colombani, J., Narasimha, S., McCusker, D., Léopold, P., and Boulan, L.
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DROSOPHILA ,SYMMETRY (Biology) ,MORPHOGENESIS ,ECDYSONE ,TISSUES ,EPIDERMIS - Abstract
The control of organ size mainly relies on precise autonomous growth programs. However, organ development is subject to random variations, called developmental noise, best revealed by the fluctuating asymmetry observed between bilateral organs. The developmental mechanisms ensuring bilateral symmetry in organ size are mostly unknown. In Drosophila, null mutations for the relaxin-like hormone Dilp8 increase wing fluctuating asymmetry, suggesting that Dilp8 plays a role in buffering developmental noise. Here we show that size adjustment of the wing primordia involves a peak of dilp8 expression that takes place sharply at the end of juvenile growth. Wing size adjustment relies on a cross-organ communication involving the epidermis as the source of Dilp8. We identify ecdysone signaling as both the trigger for epidermal dilp8 expression and its downstream target in the wing primordia, thereby establishing reciprocal hormonal feedback as a systemic mechanism, which controls organ size and bilateral symmetry in a narrow developmental time window. Mechanisms ensuring developmental precision are poorly understood. Here Blanco-Obregon et al. report reciprocal feedback between Dilp8 and Ecdysone, two hormones required during a precise time window of Drosophila development for organ size adjustment. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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8. Effect of asymmetric strain relaxation on dislocation relaxation processes in heteroepitaxial semiconductors.
- Author
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Andersen, D. and Hull, R.
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SEMICONDUCTOR detectors ,NITRIDES ,HEAT resistant alloys ,ORTHOGONAL systems ,TENSILE strength - Abstract
The effect of asymmetric interfacial strain configurations upon the generation of misfit dislocation arrays in lattice mismatched epitaxy is considered. For example, elastic strain relaxation for Si
1-x Gex /Si(110) films is uniaxial, assuming glide on {111} planes as expected for the diamond cubic system, which leads to asymmetric strain relief. Here, we extend our previously developed relaxation model for generation of dislocation arrays in SiGe/Si, by accounting for how the different energetics of asymmetrically strained films affect the kinetics of the relaxation process. Similarly, non-polar III-nitride epitaxial films have asymmetric strain from the outset of growth due to the different c/a lattice parameter ratios. In both systems, the asymmetric strain is represented by an additional term in the misfit dislocation applied stress equation. In SiGe/Si(110), a simple elasticity analysis of the strain produced by the uniaxial array of dislocations predicts that the relaxation orthogonal to the dislocation line direction occurs at a faster rate than predicted by purely biaxial strain relief due to the contributions of the strain parallel to the dislocations. This difference is because the strain parallel to the dislocation line directions continues to resolve stress onto the misfit dislocations even as the orthogonal strain is minimized. As a result, the minimum strain energy is predicted to occur for a dislocation spacing, which produces tensile layer strain in the orthogonal direction. Such tensile strain may modify the (opto)electronic properties of a Si, Ge, or GeSi epilayer but is only predicted to occur for advanced stages of relaxation. These asymmetric derivations are applicable to any thin film system where strain is not strictly biaxial. [ABSTRACT FROM AUTHOR]- Published
- 2017
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9. Materials genomics of thin film strain relaxation by misfit dislocations.
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Hull, R., Parvaneh, H., Andersen, D., and Bean, John C.
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THIN films ,STRAINS & stresses (Mechanics) ,RELAXATION (Nuclear physics) ,DISLOCATIONS in metals ,LATTICE theory ,EPITAXY - Abstract
We summarize the development and implementation of a "process simulator" for modeling thin film strain relaxation by injection of misfit dislocations. The process simulator, initially developed for Ge
x Si1–x /Si(100) lattice-mismatched epitaxy, integrates elasticity and dislocation theory with experimental measurements of kinetic parameters describing dislocation nucleation, propagation, and interactions. This enables predictive simulation of the development of misfit dislocation arrays during growth and thermal annealing sequences. Further, in the spirit of the materials genome initiative, we show how once a relatively complete description is built for one materials system, extension to a related system may be implemented using a greatly reduced data set. We illustrate this concept by translation of the simulator for Gex Si1–x /Si(100) epitaxy into predictive simulation for the Gex Si1–x /Si(110) system (which has quite different dislocation microstructure and kinetics) using greatly reduced data sets for the latter system and incorporating data refinement methods to extract unknown kinetic parameters. This sets the platform for extension of these methods to a broader set of strained layer systems. [ABSTRACT FROM AUTHOR]- Published
- 2015
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10. Characteristics of patients with familial Mediterranean fever in Denmark: a retrospective nationwide register-based cohort study.
- Author
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Mortensen, SB, Hansen, AE, Lundgren, J, Barfod, TS, Ambye, L, Dunø, M, Schade Larsen, C, Andersen, DC, Jakobsen, MA, Johansen, IS, Mortensen, S B, Hansen, A E, Barfod, T S, Andersen, D C, Jakobsen, M A, and Johansen, I S
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FAMILIAL Mediterranean fever ,COHORT analysis ,HOSPITAL admission & discharge - Abstract
Objectives: To investigate epidemiology, demography, and genetic and clinical characteristics of patients with familial Mediterranean fever (FMF) in Denmark. Method: In this population-based, cross-sectional cohort study, we identified FMF patients from discharge diagnoses using ICD-10 codes in the Danish National Patient Register, and linked data from the Danish Civil Registration System and laboratory databases for results of MEFV gene variant screening. Results: We identified 495 FMF patients (prevalence 1:11 680) with a median age of 29 years and a female ratio of 51%. The median age at diagnosis of FMF was 13 (IQR 7-22) years, with an estimated median diagnostic delay of 3 (IQR 0.7-6.9) years. The predominant ethnicities were Turkish (41.8%), Lebanese (15.8%), Syrian (6.5%), South-West Asian (7.9%), and South-East Asian (3.0%). The MEFV genotype distribution was 18.7% homozygous, 21.2% compound heterozygous, 32.0% heterozygous, 11.0% with complex alleles or unresolved zygosity, and 17.1% with no detected variants. M694V was the most prevalent variant in the overall cohort (32.5%). Homozygous or compound heterozygous MEFV exon 10 variants were associated with younger age at diagnosis (p < 0.001) and reduced number of hospital contacts before diagnosis (p = 0.008). The Charlson Comorbidity Index was ≥ 2 in 8.1% of patients. The prevalence of amyloidosis was 1.0%. Conclusions: FMF in Denmark is rare and patients are mainly of Eastern Mediterranean ethnicity. Diagnostic delay was long but patients with exon 10 MEFV variants were diagnosed at a younger age. Prolonged diagnostic delay is probably caused by lack of FMF awareness in the Danish healthcare system. [ABSTRACT FROM AUTHOR]
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- 2020
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11. A coupled mode approach to modulation instability and envelope solitons.
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Andersen, D. R., Datta, S., and Gunshor, R. L.
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- 1983
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12. Monte Carlo calculation of the electron drift velocity in GaAs with a superlattice.
- Author
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Andersen, D. Lange and Aas, Einar J.
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- 1973
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13. SWINE FINISHING ROOM AIR INFILTRATION: PART 2. INFILTRATION AS AFFECTED BY ROOM CHARACTERISTICS.
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Jadhav, H. T., Hoff, S. J., Harmon, J. D., and Andersen, D. S.
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- 2018
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14. NARASIN AS A MANURE ADDITIVE TO REDUCE METHANE PRODUCTION FROM SWINE MANURE.
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Andersen, D. S., Yang, F., Trabue, S. L., Kerr, B. J., and Howe, A.
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- 2018
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15. SWINE FINISHING ROOM AIR INFILTRATION: PART 1. QUANTIFICATION AND PREDICTION.
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Jadhav, H. T., Hoff, S. J., Harmon, J. D., Alvarez, I., Andersen, D. S., and Passe, U.
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- 2018
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16. Stromatolite records of environmental change in perennially ice-covered Lake Joyce, McMurdo Dry Valleys, Antarctica.
- Author
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Mackey, T. J., Sumner, D. Y., Hawes, I., Leidman, S. Z., Andersen, D. T., and Jungblut, A. D.
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STROMATOLITES ,ICE sheets ,GLOBAL environmental change ,LAKES - Abstract
Calcite-rich columnar stromatolites grew in perennially ice-covered Lake Joyce in the McMurdo Dry Valleys, Antarctica, during a period of environmental change associated with rising lake level. Stromatolite calcite contains carbon and oxygen isotope records of changes to microbial activity in response to variable light environments and water chemistry through time. The stromatolites grew synchronously with correlative calcite zones. The innermost (oldest) calcite zone has a wide range of δC values consistent with variable photosynthetic effects on local DIC C/C. Subsequent calcite zones preserve a progressive enrichment in δC values of approximately + 2.6‰ through time, with δC values becoming less variable. This enrichment likely records the removal of C by photosynthesis from the DIC reservoir over decades, with photosynthetic effects decreasing as light levels became lower and more consistent through time. Mean δO values of the innermost calcified zone were at least 1‰ lower than those of the other calcified zones ( t test p-level < 0.001). The significant difference in δO values between the innermost and other calcified zones could be a product of mixing source waters with different isotopic values associated with the initiation of lake stratification associated with rising lake level. Overall, Lake Joyce stromatolites record significant lateral variability in relative photosynthetic rate and long-lived lake water stratification with microbial modification of the DIC pool. Such processes provide criteria for interpreting microbial activity within polar paleolake deposits and may shed light on variability in lake environments associated with changing climate in the McMurdo Dry Valleys. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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17. A COUNTY-LEVEL ASSESSMENT OF MANURE NUTRIENT AVAILABILITY RELATIVE TO CROP NUTRIENT CAPACITY IN IOWA: SPATIAL AND TEMPORAL TRENDS.
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Andersen, D. S. and Pepple, L. M.
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- 2017
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18. Narasin effects on energy, nutrient, and fiber digestibility in corn-soybean meal or corn-soybean meal-dried distillers grains with solubles diets fed to 16-, 92-, and 141-kg pigs.
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Kerr, B. J., Trabue, S. L., and Andersen, D. S.
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FIBER in animal nutrition ,CORN as feed ,SOYBEAN as feed ,SWINE nutrition ,DISTILLERY by-products - Abstract
Three experiments were conducted to determine the effect of narasin on growth performance and on GE and nutrient digestibility in nursery, grower, and finishing pigs fed either a corn-soybean meal (CSBM) diet or a CSBM diet supplemented with distillers dried grains with solubles (DDGS), in combination with either 0 or 30 mg narasin/kg of diet. In Exp. 1 (64 gilts, initial BW = 9.0 kg, SD = 1.0 kg) and Exp. 2 (60 gilts. initial BW = 81.1 kg, SD = 6.1 kg), gilts were allotted into individual pens and fed their experimental diets for 24 and 21 d, respectively. On the last 2 d of each experiment, fecal samples were collected to assess apparent total tract digestibility (ATTD) of GE and various nutrients. In Exp. 3, 2 separate groups of 24 gilts (initial BW = 145.1 kg, SD = 7.8 kg) were allotted to individual metabolism crates and fed their experimental diets for 30 d prior to a time-based 6-d total fecal collection period to assess GE and nutrient digestibility. In Exp. 1, there was an interaction between diet type and narasin addition for G:F and for many of the ATTD coefficients measured. When narasin was supplemented to the CSBM diet, ATTD of GE, DM, C, S, phosphorus, NDF, and ADF was either not changed or reduced, while when narasin was supplemented to DDGS diets, these same ATTD parameters were increased (interaction, P ≤ 0.05). Even though ADG and ADFI were not affected, G:F] was improved in pigs fed the CSBM diet with supplemental narasin, but was reduced in pigs fed the DDGS diet with supplemental narasin (interaction, P < 0.05). In Exp. 2, there was an interaction between diet type and narasin supplementation only for ATTD of Ca (interaction, P < 0.01), in that narasin supplementation did not change the ATTD of Ca in pigs fed the CSBM diet, while narasin supplementation reduced the ATTD of Ca in pigs fed the DDGS containing diet. In Exp. 3, there was an interaction between diet and narasin only for ATTD of C (interaction, P < 0.01) in that narasin supplementation resulted in an increased ATTD of C in pigs fed the CSBM diet, while narasin supplementation to the DDGS containing diet resulted in a reduced ATTD of Ca. In general, the data indicate that narasin interacted with and had its largest effect on pig performance and GE or nutrient digestibility in 9 to 23 kg pigs compared to pigs weighing greater than 80 kg. The data also indicate that the addition of DDGS reduced GE, DM, Ca, and N digestibility, regardless of BW. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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19. Using the multi-object adaptive optics demonstrator RAVEN to observe metal-poor stars in and towards the Galactic Centre.
- Author
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Lamb, M., Venn, K., Andersen, D., Oya, S., Shetrone, M., Fattahi, A., Howes, L., Asplund, M., Lardière, O., Akiyama, M., Ono, Y., Terada, H., Hayano, Y., Suzuki, G., Blain, C., Jackson, K., Correia, C., Youakim, K., and Bradley, C.
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METAL-poor stars ,STAR observations ,ADAPTIVE optics ,GALACTIC center ,COSMIC abundances ,INFRARED spectroscopy - Abstract
The chemical abundances for five metal-poor stars in and towards the Galactic bulge have been determined from the H-band infrared spectroscopy taken with the RAVEN multi-object adaptive optics science demonstrator and the Infrared Camera and Spectrograph at the Subaru 8.2-m telescope. Three of these stars are in the Galactic bulge and have metallicities between -2.1<[Fe/H]<-1.5, and high [α/Fe]~+0.3, typical of Galactic disc and bulge stars in this metallicity range; [Al/Fe] and [N/Fe] are also high, whereas [C/Fe] < +0.3. An examination of their orbits suggests that two of these stars may be confined to the Galactic bulge and one is a halo trespasser, though proper motion values used to calculate orbits are quite uncertain. An additional two stars in the globular cluster M22 show [Fe/H] values consistent to within 1σ, although one of these two stars has [Fe/H] = -2.01 ± 0.09, which is on the low end for this cluster. The [α/Fe] and [Ni/Fe] values differ by 2σ, with the most metal-poor star showing significantly higher values for these elements. M22 is known to show element abundance variations, consistent with a multipopulation scenario though our results cannot discriminate this clearly given our abundance uncertainties. This is the first science demonstration of multiobject adaptive optics with high-resolution infrared spectroscopy, and we also discuss the feasibility of this technique for use in the upcoming era of 30-m class telescope facilities. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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20. Growth of elaborate microbial pinnacles in Lake Vanda, Antarctica.
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Sumner, D. Y., Jungblut, A. D., Hawes, I., Andersen, D. T., Mackey, T. J., and Wall, K.
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LAKES ,LAKE microbiology ,CYANOBACTERIA ,FLUORIMETRY ,BIOMASS production - Abstract
Microbial pinnacles in ice-covered Lake Vanda, McMurdo Dry Valleys, Antarctica, extend from the base of the ice to more than 50 m water depth. The distribution of microbial communities, their photosynthetic potential, and pinnacle morphology affects the local accumulation of biomass, which in turn shapes pinnacle morphology. This feedback, plus environmental stability, promotes the growth of elaborate microbial structures. In Lake Vanda, all mats sampled from greater than 10 m water depth contained pinnacles with a gradation in size from <1-mm-tall tufts to pinnacles that were centimeters tall. Small pinnacles were cuspate, whereas larger ones had variable morphology. The largest pinnacles were up to ~30 cm tall and had cylindrical bases and cuspate tops. Pinnacle biomass was dominated by cyanobacteria from the morphological and genomic groups Leptolyngbya, Phormidium, and Tychonema. The photosynthetic potential of these cyanobacterial communities was high to depths of several millimeters into the mat based on PAM fluorometry, and sufficient light for photosynthesis penetrated ~5 mm into pinnacles. The distribution of photosynthetic potential and its correlation to pinnacle morphology suggests a working model for pinnacle growth. First, small tufts initiate from random irregularities in prostrate mat. Some tufts grow into pinnacles over the course of ~3 years. As pinnacles increase in size and age, their interiors become colonized by a more diverse community of cyanobacteria with high photosynthetic potential. Biomass accumulation within this subsurface community causes pinnacles to swell, expanding laminae thickness and creating distinctive cylindrical bases and cuspate tops. This change in shape suggests that pinnacle morphology emerges from a specific distribution of biomass accumulation that depends on multiple microbial communities fixing carbon in different parts of pinnacles. Similarly, complex patterns of biomass accumulation may be reflected in the morphology of elaborate ancient stromatolites. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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21. Astrometry with MCAO: HST-GeMS proper motions in the globular cluster NGC 6681.
- Author
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Massari, D., Fiorentino, G., Mcconnachie, A., Bellini, A., Tolstoy, E., Turri, P., Andersen, D., Bono, G., Stetson, P. B., and Veran, J.-p.
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ASTROMETRY ,ADAPTIVE optics ,GLOBULAR clusters ,MOTION analysis ,SAGITTARIUS dwarf spheroidal galaxy - Abstract
Aims. For the first time the astrometric capabilities of the Gemini Multi-Conjugate Adaptive Optics System (GeMS) facility at the Gemini South Adaptive Optics Imager (GSAOI) camera on Gemini-South are tested to quantify the accuracy in determining stellar proper motions in the Galactic globular cluster NGC 6681. Methods. Proper motions from the Hubble Space Telescope (HST) for a sample of its stars are already available, allowing us to construct a distortion-free reference at the epoch of GeMS observations that is used to measure and correct the temporally changing distortions for each GeMS exposure. In this way, we are able to compare the corrected GeMS images with a first-epoch of HST-Advanced Camera for Survey (ACS) images to recover the relative proper motion of the Sagittarius dwarf spheroidal galaxy with respect to NGC 6681. Results. We find this to be (μ
α cos δ, μδ ) = (4:09; -3:41) mas yr-1 , which matches previous HST/ACS measurements with a very good accuracy of 0.03 mas yr-1 and with a comparable precision (rms of 0.43 mas yr-1 ). Conclusions. This study successfully demonstrates that high-quality proper motions can be measured for relatively large fields of view (85" x 85") with MCAO-assisted, ground-based cameras and provides a first, successful test of the performances of GeMS on multi-epoch data. [ABSTRACT FROM AUTHOR]- Published
- 2016
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22. IMPACT OF DIETARY CARBOHYDRATE AND PROTEIN SOURCE AND CONTENT ON SWINE MANURE FOAMING PROPERTIES.
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Van Weelden, M. B., Andersen, D. S., Kerr, B. J., Trabue, S. L., Rosentrater, K. A., Pepple, L. M., and dos Santos, T. M. B.
- Published
- 2016
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23. Bacteriophages in Arctic and Antarctic low-temperature systems.
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Filippova, S., Surgucheva, N., Sorokin, V., Akimov, V., Karnysheva, E., Brushkov, A., Andersen, D., and Gal'chenko, V.
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BACTERIOPHAGES ,BACTERIAL diversity ,PHYSIOLOGY - Abstract
Comparative analysis of the presence of bacteriophages was carried out for the water column of a permanently ice-covered, extremely oligotrophic Lake Untersee (East Antarctica) and the ancient ice wedge of the Mamontova Gora outcrop (Aldan River, Central Yakutia). Microscopy revealed bacteriophages in the Mamontova Gora ice samples and in the lysates of the pure cultures of phage-sensitive bacteria isolated from the same samples. Bacteriophages isolated from these cultures were filamentous and interacted with bacteria as moderate (lysogenic) phages. A similar filamentous bacteriophage was isolated from the Lake Untersee water column. The highest morphological diversity of bacteriophages was revealed by microscopy in the oxic Lake Untersee water column in the chemocline zone (70-76 m) and in the sulfide layer (85 m). Detection of similar filamentous bacteriophages in a relic ice sample and in the samples from Antarctic Lake Untersee indicate wide occurrence of bacteriophages and lysogeny in microbial communities of low-temperature ecosystems. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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24. AN EVALUATION OF THE PHYSICOCHEMICAL AND BIOLOGICAL CHARACTERISTICS OF FOAMING SWINE MANURE.
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Van Weelden, M. B., Andersen, D. S., Trabue, S. L., Kerr, B. J., Rosentrater, K. A., and Pepple, L. M.
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ANIMAL waste ,LIVESTOCK ,SWINE ,STANDARDS - Abstract
Foam accumulation in deep-pit manure storages is an increasing concern for swine producers because of the logistical and safety-related problems it creates. To investigate this phenomenon, samples of swine manure were collected over a 13-month period from 58 swine production facilities in Iowa with varying levels of foam accumulation. Samples were tested for a number of physical, chemical, and biological parameters including pH, total and volatile solids, volatile fatty acid concentration, long-chain free fatty acid concentration, biochemical methane potential, methane production rate, surface tension, foaming capacity, and foam stability. Statistical analysis indicated that manure collected from facilities with foam accumulation produced methane at significantly (p < 0.05) faster rates than non-foaming manures (0.148 ±0.004 and 0.049 ±0.003 L CH
4 L-1 slurry d-1 , respectively) and consequently had significantly (p < 0.05) greater fluxes of biogas moving through the manure. The biochemical methane production assay suggested that manure from foaming pits had less potential to generate methane (123 ±9 mL CH4 g-1 VS) than manure from non-foaming pits (150 ±9 mL CH4 g-1 VS), presumably because more of the methane potential had previously been consumed, as indicated by the higher methane production rates. Short-chain fatty acid concentrations were significantly lower in foaming manures (4200 ±570 mg kg-1 ) than nonfoaming manures (9470 ±730 mg kg-1 ). The methane production rate, biochemical methane potential, and short-chain fatty acid assays suggest enhanced anaerobic digestion efficiency from foaming barns as compared to non-foaming barns. Other assays, such as surface tension and foaming capacity, indicated an accumulation of a surfactant at the manure-air interface of the foam, which may be capturing biogas bubbles generated within the manure. Most importantly, the foam layers exhibited a greatly enhanced ability to stabilize bubbles, which appeared to be correlated to the higher solids concentrations that stabilize the bubbles. [ABSTRACT FROM AUTHOR]- Published
- 2015
- Full Text
- View/download PDF
25. Cyanobacterial diversity in benthic mats of the McMurdo Dry Valley lakes, Antarctica.
- Author
-
Zhang, L., Jungblut, A., Hawes, I., Andersen, D., Sumner, D., and Mackey, T.
- Subjects
CYANOBACTERIA ,BACTERIAL diversity ,ICE sheets ,RIBOSOMAL RNA - Abstract
Perennially ice-covered, meromictic lakes in the McMurdo Dry Valleys, Antarctica, are useful models to study the relationship between cyanobacterial and environmental variables. They have rich benthic cyanobacterial mat accumulations and stable stratification of physical and chemical conditions. Here, we evaluated cyanobacteria from benthic mats from multiple depths in three geographically separated ice-covered lakes, Lakes Vanda, Hoare and Joyce, using 16S rRNA gene clone libraries. We identified 19 ribotypes, mostly Oscillatoriales and several Chroococcales, as well as potentially novel cyanobacterial ribotypes. The majority of ribotype diversity was shared between lakes, and only a weak relationship between ribotype community structure and environmental variables was evident. Multivariate analysis of all lake-depth combinations implied that photosynthetically active radiation, dissolved reactive phosphorus and conductivity were potentially important for shaping benthic communities in McMurdo Dry Valley lakes. Cyanobacterial-specific pigment signature analysis by high-performance liquid chromatography showed that the cyanobacterial communities responded to light conditions similarly, irrespective of community composition. The results imply a capability within a suite of cyanobacteria to colonise, adapt and grow across broad environmental ranges and geographic space, and such adaptability may provide a high degree of community resistance and resilience to future climate-driven environmental change in Antarctic terrestrial aquatic ecosystems. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
26. Modeling circulation and seasonal fluctuations in perennially ice-covered and ice-walled Lake Untersee, Antarctica.
- Author
-
Steel, H. C. B., McKay, C. P., and Andersen, D. T.
- Subjects
LAKE circulation ,GLACIERS ,ICE formation & growth ,BATHYMETRY ,MARINE geophysics - Abstract
Lake Untersee, Antarctica, is a freshwater perennially ice covered lake bounded along its north by the Anuchin glacier. The Massachusetts Institute of Technology general circulation model, used on a representative wedge-shaped lake and actual bathymetry for Lake Untersee, produces estimates for circulation and long-term temperature and mixing trends. Modeled circulation is dominated by an anticyclonic gyre in front of the glacier, with slower [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
27. Growth of modern branched columnar stromatolites in Lake Joyce, Antarctica.
- Author
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Mackey, T. J., Sumner, D. Y., Hawes, I., Jungblut, A. D., and Andersen, D. T.
- Subjects
DECIMETER waves ,STROMATOLITES ,SEDIMENTARY structures ,CALCITE crystals - Abstract
Modern decimeter-scale columnar stromatolites from Lake Joyce, Antarctica, show a change in branching pattern during a period of lake level rise. Branching patterns correspond to a change in cyanobacterial community composition as preserved in authigenic calcite crystals. The transition in stromatolite morphology is preserved by mineralized layers that contain microfossils and cylindrical molds of cyanobacterial filaments. The molds are composed of two populations with different diameters. Large diameter molds (>2.8 μm) are abundant in calcite forming the oldest stromatolite layers, but are absent from younger layers. In contrast, <2.3 μm diameter molds are common in all stromatolites layers. Loss of large diameter molds corresponds to the transition from smooth-sided stromatolitic columns to branched and irregular columns. Mold diameters are similar to trichome diameters of the four most abundant living cyanobacteria morphotypes in Lake Joyce: Phormidium autumnale morphotypes have trichome diameters >3.5 μm, whereas Leptolyngbya antarctica, L. fragilis, and Pseudanabaena frigida morphotypes have diameters <2.3 μm. P. autumnale morphotypes were only common in mats at <12 m depth. Mats containing abundant P. autumnale morphotypes were smooth, whereas mats with few P. autumnale morphotypes contained small peaks and protruding bundles of filaments, suggesting that the absence of P. autumnale morphotypes allowed small-scale topography to develop on mats. Comparisons of living filaments and mold diameters suggest that P. autumnale morphotypes were present early in stromatolite growth, but disappeared from the community through time. We hypothesize that the mat-smoothing behavior of P. autumnale morphotypes inhibited nucleation of stromatolite branches. When P. autumnale morphotypes were excluded from the community, potentially reflecting a rise in lake level, short-wavelength roughness provided nuclei for stromatolite branches. This growth history provides a conceptual model for initiation of branched stromatolite growth resulting from a change in microbial community composition. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
28. Long-term high fat feeding of rats results in increased numbers of circulating microvesicles with pro-inflammatory effects on endothelial cells.
- Author
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Heinrich, L. F., Andersen, D. K., Cleasby, M. E., and Lawson, C.
- Subjects
REACTIVE oxygen species ,ANALYSIS of variance ,ANIMAL experimentation ,BIOLOGICAL models ,CELL adhesion molecules ,ENDOTHELIUM ,FLOW cytometry ,FAT content of food ,INFLAMMATION ,OBESITY ,PROBABILITY theory ,STATISTICS ,T-test (Statistics) ,PHENOTYPES ,DATA analysis ,OXIDATIVE stress ,REPEATED measures design ,DATA analysis software ,MANN Whitney U Test ,KRUSKAL-Wallis Test - Abstract
Obesity and type 2 diabetes lead to dramatically increased risks of atherosclerosis and CHD. Multiple mechanisms converge to promote atherosclerosis by increasing endothelial oxidative stress and up-regulating expression of pro-inflammatory molecules. Microvesicles (MV) are small ( < 1 μm) circulating particles that transport proteins and genetic material, through which they are able to mediate cell–cell communication and influence gene expression. Since MV are increased in plasma of obese, insulin-resistant and diabetic individuals, who often exhibit chronic vascular inflammation, and long-term feeding of a high-fat diet (HFD) to rats is a well-described model of obesity and insulin resistance, we hypothesised that this may be a useful model to study the impact of MV on endothelial inflammation. The number and cellular origin of MV from HFD-fed obese rats were characterised by flow cytometry. Total MV were significantly increased after feeding HFD compared to feeding chow (P< 0·001), with significantly elevated numbers of MV derived from leucocyte, endothelial and platelet compartments (P< 0·01 for each cell type). MV were isolated from plasma and their ability to induce reactive oxygen species (ROS) formation and vascular cell adhesion molecule (VCAM)-1 expression was measured in primary rat cardiac endothelial cells in vitro. MV from HFD-fed rats induced significant ROS (P< 0·001) and VCAM-1 expression (P= 0·0275), indicative of a pro-inflammatory MV phenotype in this model of obesity. These findings confirm that this is a useful model to further study the mechanisms by which diet can influence MV release and subsequent effects on cardio-metabolic health. [ABSTRACT FROM PUBLISHER]
- Published
- 2015
- Full Text
- View/download PDF
29. Post-independence fledgling ecology in a migratory songbird: implications for breeding-grounds conservation.
- Author
-
Streby, H. M., Peterson, S. M., Kramer, G. R., and Andersen, D. E.
- Subjects
MIGRATORY birds ,BIRD breeding ,HABITATS ,ARTIFICIAL habitats ,NEST building ,BABY birds - Abstract
For migratory songbirds, breeding-grounds conservation and management plans are generally focused on habitat associated with locations of singing males and sometimes nesting females. However, habitat structure is often different in areas used for raising fledglings compared with areas used for song territories, and very little is known about habitat use by fledglings after independence from adult care. From 2010 to 2012, we used radiotelemetry to monitor 68 fledgling golden-winged warblers V ermivora chrysoptera after independence from adult care in mixed managed forests of Minnesota, US and Manitoba, Canada. This species is of high conservation concern in the US, is listed as threatened in Canada and is listed as near threatened on the International Union for Conservation of Nature Red List. We assessed distance and orientation of independent fledgling movements and we used compositional analysis to test for selection among cover types. Fledglings of this species, commonly described as a shrubland specialist, selected mature forest (78% of locations) over all other cover types, and foraged in forest canopy and understory in mixed-species flocks. Fledgling golden-winged warbler movements were apparently associated with habitat optimization (although prioritizing foraging over predator avoidance), and likely not with commencement of migration, or scouting future breeding territories. Ten days after independence, fledglings were an average of 1238 m north of their nest, which may be related to homing-target formation and the species' northward range expansion. We conclude that consideration for independent fledgling habitat associations is necessary for developing full-fledged forest management plans on the breeding grounds of migratory songbirds. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
30. Hulu in the neighborhood.
- Author
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Han, D., Andersen, D., Kaminsky, M., Papagiannaki, D., and Seshan, S.
- Published
- 2011
- Full Text
- View/download PDF
31. NFIRAOS: TMT narrow field near-infrared facility adaptive optics.
- Author
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Herriot, Glen, Hickson, Paul, Ellerbroek, B. L., Andersen, D. A., Davidge, T., Erickson, D. A., Powell, I. P., Clare, R., Gilles, L., Boyer, C., Smith, M., Saddlemyer, L., and Véran, J.-P.
- Published
- 2006
- Full Text
- View/download PDF
32. LINC-NIRVANA: the single arm MCAO experiment.
- Author
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Egner, Sebastian E., Gaessler, Wolfgang, Herbst, Tom M., Ragazzoni, Roberto, Stuik, Remko, Andersen, D. A., Arcidiacono, C., Baumeister, H., Beckmann, U., Behrend, J., Bertram, T., Bizenberger, P., Boehnhardt, H., Diolaiti, E., Driebe, T., Eckhardt, A., Farinato, J., Kuerster, M., Laun, W., and Ligori, S.
- Published
- 2004
- Full Text
- View/download PDF
33. WHAT IS IT WORTH? THE ECONOMIC VALUE OF MANURE TESTING.
- Author
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Regan, K. B. and Andersen, D. S.
- Subjects
MANURES ,AGRICULTURAL productivity ,DECISION making ,AGRONOMY ,ECONOMICS ,MANAGEMENT - Abstract
Animal manure is a valuable fertilizer for crop production, but effective utilization requires knowledge of the manure's nutrient content. This warrants that the manure be sampled and tested to make informed management decisions. However, there has been low adoption of annual manure testing (ca. 20% of farms). Presumably, this is because farmers view the costs and efforts of testing to be greater than the benefits. To evaluate the monetary value of manure testing, a model was developed. Using published literature values of manure nutrient concentrations and other agronomic factors as inputs, this model assesses how production expenses and incomes change with knowledge of manure's nutrient content. The model suggests that when applying manure at a nitrogen-limited rate, sampling manure before application increases profits by $20 to $68 ha
-1 , and sampling during application increases profits by $3 to $50 ha-1 . When applying manure at a phosphorus-limited rate, profits increase by $4 to $22 ha-1 when samples are analyzed either before or during application. These results illustrate that manure testing is economically beneficial and indicate that when application is nitrogen limited, manure should be sampled prior to application. If applying manure at a phosphorus-limited rate, sampling during application is recommended. [ABSTRACT FROM AUTHOR]- Published
- 2014
- Full Text
- View/download PDF
34. Local overexpression of the myostatin propeptide increases glucose transporter expression and enhances skeletal muscle glucose disposal.
- Author
-
Cleasby, M. E., Jarmin, S., Eilers, W., Elashry, M., Andersen, D. K., Dickson, G., and Foster, K.
- Subjects
GLUCOSE transporters ,GENE expression ,MYOSTATIN ,OBESITY treatment ,INSULIN resistance ,SKELETAL muscle ,SOMATOMEDIN C - Abstract
Insulin resistance (IR) in skeletal muscle is a prerequisite for type 2 diabetes and is often associated with obesity. IR also develops alongside muscle atrophy in older individuals in sarcopenic obesity. The molecular defects that underpin this syndrome are not well characterized, and there is no licensed treatment. Deletion of the transforming growth factor-β family member myostatin, or sequestration of the active peptide by overexpression of the myostatin propeptide/latency-associated peptide (ProMyo) results in both muscle hypertrophy and reduced obesity and IR. We aimed to establish whether local myostatin inhibition would have a paracrine/autocrine effect to enhance glucose disposal beyond that simply generated by increased muscle mass, and the mechanisms involved. We directly injected adenoassociated virus expressing ProMyo in right tibialis cranialis/extensor digitorum longus muscles of rats and saline in left muscles and compared the effects after 17 days. Both test muscles were increased in size (by 7 and 11%) and showed increased radiolabeled 2-deoxyglucose uptake (26 and 47%) and glycogen storage (28 and 41%) per unit mass during an intraperitoneal glucose tolerance test. This was likely mediated through increased membrane protein levels of GLUT1 (19% higher) and GLUT4 (63% higher). Interestingly, phosphorylation of phosphoinositol 3-kinase signaling intermediates and AMPactivated kinase was slightly decreased, possibly because of reduced expression of insulin-like growth factor-I in these muscles. Thus, myostatin inhibition has direct effects to enhance glucose disposal in muscle beyond that expected of hypertrophy alone, and this approach may offer potential for the therapy of IR syndromes. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
35. VEGETATIVE TREATMENT SYSTEM IMPACTS ON GROUNDWATER QUALITY.
- Author
-
Andersen, D. S., Burns, R. T., Helmers, M. J., and Moody, L. B.
- Subjects
FEEDLOT runoff ,ENVIRONMENTAL security ,WATER quality ,GROUNDWATER ,NITROGEN - Abstract
Increased environmental awareness has prompted the need for improved feedlot runoff control. Vegetative treatment systems (VTSs) provide a cost-effective option that may enhance environmental security by protecting water quality. Vegetative treatment systems are typically designed on the basis of hydraulic performance, which may result in excess application of some nutrients, specifically nitrogen and phosphorus. Groundwater quality monitoring is required to determine the effect, if any, that VTSs have on groundwater. Shallow groundwater (2 to 10 m) quality beneath six VTSs in Iowa was monitored over a four-year period. Monitoring wells were located upgradient, within, and downgradient of the VTSs. Groundwater samples were collected on a monthly basis and analyzed for ammoniacal nitrogen, chloride, nitratenitrogen, and fecal coliforms. A trend analysis was conducted to evaluate groundwater response patterns to VTS construction and use. In general, monitoring wells located within and downgradient of the VTS showed increasing trends in chloride and decreasing trends in nitrate concentrations. No trends for fecal coliforms or ammoniacal nitrogen were seen. Statistical analysis was performed to test for concentration differences between upgradient, within, and downgradient monitoring wells. In general, no differences in ammoniacal nitrogen concentration were seen. Fecal coliform concentrations were generally highest at the monitoring well within the VTS, but no difference was found between upgradient and downgradient concentrations. Chloride concentrations were generally significantly higher within and downgradient of the VTS when compared to the upgradient well; nitrate concentrations were generally significantly lower within and downgradient of the VTA than upgradient. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
36. The prokaryotic community of subglacial bottom sediments of Antarctic Lake Untersee: Detection by cultural and direct microscopic techniques.
- Author
-
Mulyukin, A., Demkina, E., Manucharova, N., Akimov, V., Andersen, D., McKay, C., and Gal'chenko, V.
- Subjects
PROKARYOTES ,MARINE sediments ,MICROSCOPY ,FLUORESCENCE in situ hybridization ,PERMAFROST ,BACTERIAL cells - Abstract
The heterotrophic mesophilic microbial component was studied in microbial communities of the samples of frozen regolith collected from the glacier near Lake Untersee collected in 2011 during the joint Russian-American expedition to central Dronning Maud Land (Eastern Antarctica). Cultural techniques revealed high bacterial numbers in the samples. For enumeration of viable cells, the most probable numbers (MPN) method proved more efficient than plating on agar media. Fluorescent in situ hybridization with the relevant oligonucleotide probes revealed members of the groups Eubacteria ( Actinobacteria, Firmicutes) and Archaea. The application of the methods of cell resuscitation, such as the use of diluted media and prevention of oxidative stress, did not result in a significant increase in the numbers of viable cells retrieved from subglacial sediment samples. Our previous investigations demonstrated the necessity for special procedures for efficient reactivation of the cells from microbial communities of replace with buried soil and permafrost samples collected in the Arctic zone. The differing responses to the special resuscitation procedures may reflect the differences in the physiological and morphological state of bacterial cells in microbial communities subject to continuous or periodic low temperatures and dehydration. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
37. THE USE OF PHOSPHORUS SORPTION ISOTHERMS TO PROJECT VEGETATIVE TREATMENT AREA LIFE.
- Author
-
Baker, J. F., Andersen, D. S., Burns, R. T., and Moody, L. B.
- Subjects
FEEDLOTS ,COST effectiveness ,FEEDLOT runoff ,SUSTAINABILITY ,PHOSPHORUS ,SOIL absorption & adsorption - Abstract
Beef feedlots of all sizes are looking for cost-effective solutions to manage feedlot runoff. Vegetative treatment systems (VTSs) are a potential option. VTSs consist of a solids settling structure followed by additional treatment components, such as vegetative infiltration basins (VIBs) and/or vegetative treatment areas (VTAs) that use soil and vegetation to treat nutrients in the applied runoff Investigations have shown that VTSs can provide a cost-effective means of controlling feedlot runoff" however, their sustainability and life expectancy have not yet been determined. Thus, the objective of this work is to evaluate, based on the VTA's ability to sorb and utilize phosphorus, the expected phosphorus sink life of VTSs on beef feedlots in Iowa. In doing so, we evaluated three things: (1) phosphorus removal with vegetation harvest, (2) the extent of vertical redistribution of phosphorus in the soil profile, and (3) if a mass balance approach was capable of predicting changes in soil test phosphorus. Vegetation harvest removed 6% to 16% of the applied phosphorus, and a P mass balance did an adequate job of predicting the significant increases in soil P test concentrations. Deep soil cores (1.2 m) showed that phosphorus accumulation tended to be limited to the top 0.3 m but that vertical migration was increasing. Based on this success, we proposed a P mass balance and soil sorption model to project VTA life expectancy and evaluated the sensitivity of the estimated life to different design and management alternatives. The sensitivity analysis showed that phosphorus sorption capacity and loading rate were important, but the critical depth of the soil that can be saturated has the largest impact on VTA life. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
38. Detection of phage infection in the bacterial population of Lake Untersee (Antarctica).
- Author
-
Filippova, S., Surgucheva, N., Kulikov, E., Sorokin, V., Akimov, V., Bej, A., McKay, C., Andersen, D., and Galchenko, V.
- Subjects
BACTERIOPHAGES ,AEROBIC bacteria ,BIOGEOCHEMICAL cycles ,BIOTIC communities - Abstract
The article presents information on a study conducted to determine the importance of bacteriophage population of aerobic microorganism in Untersee lake located in Antarctica. The study revealed the importance of bacteriophages in the formation of microbiota as well as maintenance of biogeochemical and ecological processes which occurs in the aquatic ecosystems.
- Published
- 2013
- Full Text
- View/download PDF
39. Impact of a physician-staffed helicopter on a regional trauma system: a prospective, controlled, observational study.
- Author
-
HESSELFELDT, R., STEINMETZ, J., JANS, H., JACOBSSON, M.‐L. B, ANDERSEN, D. L., BUGGESKOV, K., KOWALSKI, M., PRÆST, M., ØLLGAARD, L., HÖIBY, P., and RASMUSSEN, L. S.
- Subjects
HELICOPTER ambulances ,EMERGENCY medical services ,TRAUMA centers ,PATIENTS ,LOGISTIC regression analysis ,WOUNDS & injuries - Abstract
Introduction This study aims to compare the trauma system before and after implementing a physician-staffed helicopter emergency medical service ( PS-HEMS). Our hypothesis was that PS-HEMS would reduce time from injury to definitive care for severely injured patients. Methods This was a prospective, controlled, observational study, involving seven local hospitals and one level I trauma centre using a before and after design. All patients treated by a trauma team within a 5-month period (1 December 2009-30 April 2010) prior to and a 12-month period (1 May 2010-30 April 2011) after implementing a PS-HEMS were included. We compared time from dispatch of the first ground ambulance to arrival in the trauma centre for patients with Injury Severity Score ( ISS) > 15. Secondary end points were the proportion of secondary transfers and 30-day mortality. Results We included 1788 patients, of which 204 had an ISS > 15. The PS-HEMS transported 44 severely injured directly to the trauma centre resulting in a reduction of secondary transfers from 50% before to 34% after implementation ( P = 0.04). Median delay for definitive care for severely injured patients was 218 min before and 90 min after implementation ( P < 0.01). The 30-day mortality was reduced from 29% (16/56) before to 14% (21/147) after PS-HEMS ( P = 0.02). Logistic regression showed PS-HEMS had an odds ratio ( OR) for survival of 6.9 compared with ground transport. Conclusions Implementation of a PS-HEMS was associated with significant reduction in time to the trauma centre for severely injured patients. We also observed significantly reduced proportions of secondary transfers and 30-day mortality. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
40. Outcome of mentalization-based and supportive psychotherapy in patients with borderline personality disorder: a randomized trial.
- Author
-
Jørgensen, C. R., Freund, C., Bøye, R., Jordet, H., Andersen, D., and Kjølbye, M.
- Subjects
SUPPORTIVE psychotherapy ,TREATMENT of borderline personality disorder ,RANDOMIZED controlled trials ,PSYCHODYNAMIC psychotherapy ,MENTAL depression - Abstract
Objective: This study presents data from a randomized outcome study comparing mentalization-based and supportive psychotherapy for patients with borderline personality disorder (BPD). Method: Eighty-five SCID-II diagnosed borderline patients were randomized to either i) 2 years of intensive (twice weekly) combined (individual and group), mentalization-based psychotherapy (MBT) or ii) 2 years of less-intensive (biweekly) supportive group therapy. Treatment outcome was assessed using a battery of self-report questionnaires, SCID-II interviews and therapist-rated global assessment of functioning (GAF). Results: Fifty-eight patients completed 2 years of treatment. Significant changes in both treatment groups were identified for several outcome measures, including self-reported measures of general functioning, depression, social functioning and number of diagnostic criteria met for BPD, as outlined by the SCID-II interview. General linear modelling was used to compare treatment outcome in the two groups. Only GAF showed a significantly higher outcome in the MBT group. A trend was found for a higher rate of recovery from BPD in the MBT group. Pre-post effect sizes were high (0.5-2.1) and for the most part highly significant in both groups. Conclusion: The study indicates that both MBT and supportive treatment are highly effective in treating BPD when conducted by a well-trained and experienced psychodynamic staff in a well-organized clinic. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
41. Novel plant communities limit the effects of a managed flood to restore riparian forests along a large regulated river.
- Author
-
Cooper, D. J. and Andersen, D. C.
- Published
- 2012
- Full Text
- View/download PDF
42. Legacies of recent environmental change in the benthic communities of Lake Joyce, a perennially ice-covered Antarctic lake.
- Author
-
HAWES, I., SUMNER, D. Y., ANDERSEN, D. T., and MACKEY, T. J.
- Subjects
GLOBAL environmental change ,LAKES ,IRRADIATION ,PHOTOSYNTHESIS - Abstract
Many Antarctic lakes provide habitat for extensive microbial mats that respond on various timescales to environmental change. Lake Joyce contains calcifying microbialites and provides a natural laboratory to constrain how environmental changes influence microbialite development. In Lake Joyce, depth-specific distributions of calcitic microbialites, organic carbon, photosynthetic pigments and photosynthetic potential cannot be explained by current growth conditions, but are a legacy of a 7-m lake level rise between 1973 and 2009. In the well-illuminated margins of the lake, photosynthetically active benthic communities colonised surfaces submerged for just a few years. However, observed increases in accumulated organic material with depth from 5 to 20 m (2-40 mg ash-free dry weight cm
−2 ) and the presence of decimetre-scale calcite microbialites at 20-22 m depth, apparently related to in situ photosynthetic growth, are inconsistent with the current distributions of irradiance, photosynthetic pigments and mat photosynthetic potential (as revealed by pulse-amplitude-modulated fluorometry). The microbialites appeared photosynthetically active in 1986 and 1997, but were outside the depth zone where significant phototrophic growth was possible and were weakly photosynthetically competent in 2009. These complex microbial structures have persisted after growth has ceased, demonstrating how fluctuating environmental conditions and the hysteresis between environmental change, biological response and microbialite development can be important factors to consider when interpreting modern, and by inference ancient, microbially mediated structures. [ABSTRACT FROM AUTHOR]- Published
- 2011
- Full Text
- View/download PDF
43. Essential Pharmacokinetic Information for Drug Dosage Decisions: A Concise Visual Presentation in the Drug Label.
- Author
-
Menon-Andersen, D., Yu, B., Madabushi, R., Bhattaram, V., Hao, W., Uppoor, R. S., Mehta, M., Lesko, L., Temple, R., Stockbridge, N., Laughren, T., and Gobburu, J. V.
- Subjects
PHARMACOKINETICS ,PHARMACEUTICAL arithmetic ,LABELS ,INTRINSIC factor (Physiology) ,DRUG interactions - Abstract
A critical issue in labeling is to succinctly communicate, in a manner that is readily understandable and actionable, changes in systemic exposure that affect drug dosing. Current practices in labeling make it difficult for prescribers to locate the most important information influencing their dosing decisions. In this report, we propose the use of forest plots for communicating the pharmacokinetic consequences of intrinsic and extrinsic factors in a concise and readily interpretable manner. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
- View/download PDF
44. PHYSICAL AND CHEMICAL PROPERTIES OF RUNOFF EFFLUENT FROM BEEF FEEDLOTS IN IOWA.
- Author
-
Pepple, L. M., Andersen, D. S., Burns, R. T., and Moody, L. B.
- Subjects
FEEDLOT runoff ,WATER pollution ,WATER quality ,CATTLE ,NITROGEN ,PHOSPHORUS ,PARTICLE size distribution - Abstract
Beef feedlot runoff is a potential environmental contaminant. As such, it should be managed properly to preserve water quality. Primary treatment of feedlot runoff often relies on sedimentation techniques; thus, accurate knowledge of feedlot runoff physical properties is required. This study characterized the physical and chemical properties of runoff effluent from earthen and concrete beef feedlots in Iowa with the objective\of providing the necessary information to improve solid settling basin design and performance. Results, although not statistically significant (p = 0.11), indicated that solids in runoff from concrete lots tended to settle more slowly than solids from earthen lots. Particle size distribution and particle density measurements indicated that the poorer settle ability of concrete lot runoff was primarily caused by lower particle densities: 1.47 ±0.17 g cm
-3 (average ± SD) for concrete lots as compared to 1.89 ±0.11 g cm-3 for earthen lots. Runoff composition was analyzed before and after settling to relate nutrient reduction to solids removal. Results indicated an average of 41 g total Kjeldahl nitrogen per kg total solids and 16 g total phosphorus per kg total solids were removed during settling. [ABSTRACT FROM AUTHOR]- Published
- 2011
- Full Text
- View/download PDF
45. Discovery of large conical stromatolites in Lake Untersee, Antarctica.
- Author
-
ANDERSEN, D. T., SUMNER, D. Y., HAWES, I., WEBSTER-BROWN, J., and MCKAY, C. P.
- Subjects
STROMATOLITES ,SEDIMENTARY structures ,MICROBIAL mats ,MICROBIAL aggregation ,LAKES - Abstract
Lake Untersee is one of the largest (11.4 km) and deepest (>160 m) freshwater lakes in East Antarctica. Located at 71°S the lake has a perennial ice cover, a water column that, with the exception of a small anoxic basin in the southwest of the lake, is well mixed, supersaturated with dissolved oxygen, alkaline (pH 10.4) and exceedingly clear. The floor of the lake is covered with photosynthetic microbial mats to depths of at least 100 m. These mats are primarily composed of filamentous cyanophytes and form two distinct macroscopic structures, one of which - cm-scale cuspate pinnacles dominated by Leptolyngbya spp. - is common in Antarctica, but the second - laminated, conical stromatolites that rise up to 0.5 m above the lake floor, dominated by Phormidium spp. - has not previously been reported in any modern environment. The laminae that form the conical stromatolites are 0.2-0.8 mm in thickness consisting of fine clays and organic material; carbon dating implies that laminations may occur on near decadal timescales. The uniformly steep sides (59.6 ± 2.5°) and the regular laminar structure of the cones suggest that they may provide a modern analog for growth of some of the oldest well-described Archean stromatolites. Mechanisms underlying the formation of these stromatolites are as yet unclear, but their growth is distinct from that of the cuspate pinnacles. The sympatric occurrence of pinnacles and cones related to microbial communities with distinct cyanobacterial compositions suggest that specific microbial behaviors underpin the morphological differences in the structures. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
- View/download PDF
46. Wood Preservation Utilizing Organotin Polymers.
- Author
-
Andersen, D. and Becka, A.
- Published
- 1983
- Full Text
- View/download PDF
47. USE OF THE SOIL-PLANT-AIR-WATER MODEL TO PREDICT HYDRAULIC PERFORMANCE OF VEGETATIVE TREATMENT AREAS CONTROLLING OPEN LOT RUNOFF.
- Author
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Andersen, D. S., Burns, R. T., Moody, L. B., Helmers, M. J., Horton, R., and Pederson, C.
- Subjects
FEEDLOT runoff ,WATER quality management ,WATER quality ,MATHEMATICAL models ,AGRICULTURE ,ANIMAL waste - Abstract
Alternative treatment systems to control runoff from open beef feedlots may enhance environmental security and protect water quality. Several Midwestern states have issued National Pollution Discharge Elimination System permits allowing beef feedlots to use vegetative treatment systems (VTSs) to control and treat feedlot runoff. Monitoring VTSs has provided data to validate performance modeling strategies. The objective of this study was to evaluate the ability of the Soil-Plant-Air-Water (SPAW) model to predict the hydraulic performance of vegetative treatment areas (VTAs). Two approaches, one using the field module and the other the pond module of the SPAW model were investigated. The model results from the SPA W field and pond modules were compared to monitored performance data from five VTAs in Iowa. Modeling statistics were calculated to evaluate SPAW's ability to predict VTA hydraulic performance. Based on the 18 site-years of data collected, the Nash-Sutcliffe efficiency (NSE), percent bias (BIAS), and ratio of the root mean square error to the standard deviation (RSR) were 0.95, 8%, and 0.22, respectively, on an annual basis. The NSE, BIAS, and RSR for the field module were 0.32, 32%, and 0.83, respectively. The results showed that the SPAW model could be used successfully to predict the hydraulic performance of VTAs, with the pond module being more successful than the field module. [ABSTRACT FROM AUTHOR]
- Published
- 2010
- Full Text
- View/download PDF
48. COMPARISON OF THE IOWA STATE UNIVERSITY EFFLUENT LIMITATION GUIDELINES MODEL WITH THE SOIL-PLANT-AIR-WATER MODEL FOR EVALUATING CONTAINMENT BASIN PERFORMANCE.
- Author
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Andersen, D. S., Burns, R. T., Moody, L. B., Helmers, M. J., and Horton, R.
- Subjects
STORM water retention basins ,FEEDLOT runoff ,SOIL moisture ,LAND treatment of wastewater - Abstract
This article compares results from the Iowa State University Effluent Limitations Guidelines (ISU-ELG) model to results obtained using the Soil-Plant-Air-Water (SPAW) model to simulate feedlot runoff containment basin overflow volume. The objective was to verify that the ISU-ELG model was providing a reasonable prediction of basin overflow. The ISU-ELG model uses a set of guidelines to determine if land application is acceptable, whereas the SPAW model uses a soil moisture criterion. The criterion for determining if a particular day was suitable for land application of basin effluent was investigated to determine the effect on basin overflow volumes. The results show that the ISU-ELG model overpredicted the percentage of feedlot runoff controlled in comparison to the SPAW model at all five locations investigated. For wetter areas in Iowa, the number of drying days had a large effect on basin overflow volumes, whereas for the drier northwest region of Iowa, this effect was limited. Possible methods of improving the ISU-ELG model predictions include adding a soil moisture accounting function to model moisture levels in the land application area or calibrating the number of drying days required before land application can commence. Alternatively, the SPAW model can be used, but this requires additional user inputs and increases complexity in modeling the runoff control system. [ABSTRACT FROM AUTHOR]
- Published
- 2010
- Full Text
- View/download PDF
49. Low genetic diversity in the masked palm civet Paguma larvata (Viverridae).
- Author
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Patou, M.-L., Chen, J., Cosson, L., Andersen, D. H., Cruaud, C., Couloux, A., Randi, E., Zhang, S., and Veron, G.
- Subjects
PAGUMA larvata ,SARS disease ,CYTOCHROMES ,HABITATS ,VIVERRIDAE ,ANIMAL species - Abstract
The masked palm civet is distributed through south-east Asia, China and the Himalayas. Because of its potential role in the severe acute respiratory syndrome (SARS) epidemic, it has become important to gather information on this species, and notably to provide a tool to determine the origin of farm and market animals. For this purpose, we studied the genetic variability and the phylogeographic pattern of the masked palm civet Paguma larvata. First, two portions of mitochondrial genes, cytochrome b and the control region, were sequenced for a total of 76 individuals sampled from China, the Indochinese region and the Sundaic region. Results indicated a low genetic variability and suggested a lack of a phylogeographic structure in this species, which do not allow inferring the geographic origin of samples of unknown origin, although it is possible to distinguish individuals from China and the Sundaic region. This low variation is in contrast to the well-marked morphological differentiation between the populations in the Sundaic and Chinese–Indochinese regions. We also used five microsatellite loci to genotype 149 samples from two wild and four farmed populations in China, where the masked palm civet is farmed and where the SARS coronavirus was isolated. These analyses also showed a reduced variability in Chinese civets and showed that farmed populations did not exhibit a lower genetic diversity than wild populations, suggesting frequent introductions of wild individuals into farms. [ABSTRACT FROM AUTHOR]
- Published
- 2009
- Full Text
- View/download PDF
50. Integrating modes of policy analysis and strategic management practice: requisite elements and dilemmas.
- Author
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Eden, C., Ackermann, F., Bryson, J. M., Richardson, G. P., Andersen, D. F., and Finn, C. B.
- Subjects
POLICY analysis ,STRATEGIC planning ,LEADERSHIP ,STAKEHOLDERS ,MANAGEMENT - Abstract
There is a need to bring methods to bear on public problems that are inclusive, analytic, and quick. This paper describes the efforts of three pairs of academics working from three different though complementary theoretical foundations and intervention backgrounds (ie ways of working) who set out together to meet this challenge. Each of the three pairs had conducted dozens of interventions that had been regarded as successful or very successful by the client groups in dealing with complex policy and strategic problems. One approach focused on leadership issues and stakeholders, another on negotiating competitive strategic intent with attention to stakeholder responses, and the third on analysis of feedback ramifications in developing policies. This paper describes the 10-year longitudinal research project designed to address the above challenge. The important outcomes are reported: the requisite elements of a general integrated approach and the enduring puzzles and tensions that arose from seeking to design a wide-ranging multi-method approach. [ABSTRACT FROM AUTHOR]
- Published
- 2009
- Full Text
- View/download PDF
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