Artículos de revistas sobre el tema "Bergstrom Method"

The exact discrete model satisfied by equispaced data generated by a linear stochastic differential equations system is derived by a method that does not imply restrictions on observed discrete data per se. The method involves integrating the solution of the continuous time model in state space form and a nonstandard change in the order of three types of integration, facilitating the representation of the exact discrete model as an asymptotically time-invariant vector autoregressive moving average model. The method applying to the state space form is general and is illustrated using the prototypical higher order model for mixed stock and flow data discussed by Bergstrom (1986, Econometric Theory 2, 350–373).

Our paper is in the spirit of Rex Bergstrom's interests and research in cyclical growth models and his meticulous attention to underlying data series. We develop a new quarterly real GDP series for post–World War II New Zealand, derive a new “benchmark” set of classical business cycle turning points, and establish nonparametric classical cycle characteristics. Markov-switching models, estimated by Gibbs-sampling methods, are used to derive mean growth rate and volatility regimes and to add to existing knowledge. The resulting properties, involving cycle asymmetries, volatility, diversity and duration dependence, and differing mean growth rate and volatility regimes, can be used to underpin a next generation of cyclical growth models for New Zealand, in the Bergstrom tradition.

This paper offers a perspective on A.R. Bergstrom’s contribution to continuous-time modeling, focusing on his preferred method of estimating the parameters of a structural continuous-time model using an exact discrete-time analog. Some inherent difficulties in this approach are discussed, which help to explain why, in spite of his prescience, the methods around his time were not universally adopted as he had hoped. Even so, it is argued that Bergstrom’s contribution and legacy is secure and retains some relevance today for the analysis of macroeconomic and financial time series.

We use the composition method to analyse the convolutions of probability distributions by emploing the Appell polynomials and Bergström identity. Our approximation is based on the probability distributions which have the inverse generalized measure of bounded variation. The idea to use the accompanying probability distribution eλ(F−E), λ > 0, was first proposed by B.V. Gnedenko [1].

Hot deformation behavior of Fe-3%Si steel within temperature range of 1073~1473K and strain rate range of 0.01~5s−1was investigated by isothermal compression test using thermo-simulation method. Over the applied deformation conditions, steady state flow behavior was well described by the power law relationship with dislocation climb as the rate-controlling mechanism, and the high apparent activation energy can be attributed to the high yield stress. A modified Bergström model was proposed by introducing yield stress, and consequently the whole stress-strain curves can be accurately predicted.

Abstract Objective We propose the use of ultrasound-guided muscle biopsy as a viable method of obtaining muscle specimen to aid the diagnosis of myopathy. We retrospectively review the diagnostic accuracy and patient feedback of ultrasound-guided muscle biopsies in our neuromuscular service. Method Multidisciplinary team meeting reviewed select patients and agreed on those suitable for ultrasound-guided muscle biopsy. They then underwent biopsy using direct ultrasound guidance and a modified Bergström needle. The specimens were sent for histopathological analysis, and patients were given a feedback form. Results Ten patients underwent 11 ultrasound-guided muscle biopsies. Of these 11, one was processed incorrectly, but all others were good quality specimens suitable for analysis. All 10 of those processed correctly aided diagnosis. All patient feedback was rated good or excellent. In 4 patients with a previous unsuccessful surgical biopsy, ultrasound-guided biopsy was successful in obtaining suitable muscle. Of those 4 patients, 3 preferred ultrasound-guided biopsy, and 1 did not state a preference. Discussion Our ultrasound-guided muscle biopsy technique offers a viable alternative to surgical biopsy. It yields high-quality specimen that aids diagnosis and receives good feedback from patients. It can be performed quickly as a day case and does not require theatre space. Furthermore, direct visualization of structures minimizes the risk of complications and allows biopsy of otherwise difficult to access targets. Conclusion Utilization of ultrasound guided–modified Bergström needle technique for muscle biopsy provides comparable success rates to other techniques and has practical, clinical, operational, and patient-centred benefits compared with alternative techniques.

Abstract Bučas, M., Bergström, U., Downie, A-L., Sundblad, G., Gullström, M., von Numers, M., Šiaulys, A., and Lindegarth, M. 2013. Empirical modelling of benthic species distribution, abundance, and diversity in the Baltic Sea: evaluating the scope for predictive mapping using different modelling approaches. – ICES Journal of Marine Science, 70: 1233–1243. The predictive performance of distribution models of common benthic species in the Baltic Sea was compared using four non-linear methods: generalized additive models (GAMs), multivariate adaptive regression splines, random forest (RF), and maximum entropy modelling (MAXENT). The effects of data traits were also tested. In total, 292 occurrence models and 204 quantitative (abundance and diversity) models were assessed. The main conclusions are that (i) the spatial distribution, abundance, and diversity of benthic species in the Baltic Sea can be successfully predicted using several non-linear predictive modelling techniques; (ii) RF was the most accurate method for both models, closely followed by GAM and MAXENT; (iii) correlation coefficients of predictive performance among the modelling techniques were relatively low, suggesting that the performance of methods is related to specific responses; (iv) the differences in predictive performance among the modelling methods could only partly be explained by data traits; (v) the response prevalence was the most important explanatory variable for predictive accuracy of GAM and MAXENT on occurrence data; (vi) RF on the occurrence data was the only method sensitive to sampling density; (vii) a higher predictive accuracy of abundance models could be achieved by reducing variance in the response data and increasing the sample size.

AbstractMost concepts to characterize crack propagation were developed for elastic materials. When applying these methods to elastomers, the question is how the inherent energy dissipation of the material affects the cracking behavior. This contribution presents a numerical analysis of crack growth in natural rubber taking energy dissipation due to the visco-elastic material behavior into account. For this purpose, experimental tests were first carried out under different load conditions to parameterize a Prony series as well as a Bergström–Boyce model with the results. The parameterized Prony series was then used to perform numerical investigations with respect to the cracking behavior. Using the FE-software system ANSYS and the concept of material forces, the influence and proportion of the dissipative components were discussed.

This study aims at standardizing the pre-incubation and incubation pH and temperature used in the metachromatic staining method of myofibrillar ATPase activity of myosin (mATPase) used for asses and mules. Twenty four donkeys and 10 mules, seven females and three males, were used in the study. From each animal, fragments from the Gluteus medius muscle were collected and percutaneous muscle biopsy was performed using a 6.0-mm Bergström-type needle. In addition to the metachromatic staining method of mATPase, the technique of nicotinamide adenine dinucleotide tetrazolium reductase (NADH-TR) was also performed to confirm the histochemical data. The histochemical result of mATPase for acidic pre-incubation (pH=4.50) and alkaline incubation (pH=10.50), at a temperature of 37ºC, yielded the best differentiation of fibers stained with toluidine blue. Muscle fibers were identified according to the following colors: type I (oxidative, light blue), type IIA (oxidative-glycolytic, intermediate blue) and type IIX (glycolytic, dark blue). There are no reports in the literature regarding the characterization and distribution of different types of muscle fibers used by donkeys and mules when performing traction work, cargo transportation, endurance sports (horseback riding) and marching competitions. Therefore, this study is the first report on the standardization of the mATPase technique for donkeys and mules.

This study evaluated the needle muscle biopsy technique using a 6G Bergström percutaneous needle combined with histological and histochemical methods to analyze the skeletal muscle of dogs. There are few studies about canine skeletal muscles and a lack of reports in the literature about tissue collection and analysis for canine species. Evaluation of 32 German Shepherd samples collected from the gluteus medius, at a depth of 3 cm, was performed. The choice of gluteus medius and the 3-cm depth provided good quantity fragments with sufficient sizes (3–5 mm), which permitted optimal visualization of muscle fibers. Myosin ATPase, at pH 9.4, 4.6, and 4.3, and SDH reactions revealed that all muscle samples analyzed had fibers in the classic mosaic arrangement, enabling counting and typification. The mean percentages of fibers were 29.95% for type I and 70.05% for type II. On the basis of these results, we concluded that the percutaneous needle biopsy technique for canine skeletal muscles is a safe and easy procedure that obtains fragments of proper sizes, thereby enabling the study of muscle fibers. Standardization of the muscle of choice and the depth of muscle sample collection significantly contributed to this success. This is an important method to evaluate muscle fiber types of dogs and diagnose important diseases affecting the skeletal muscles.

ABSTRACTAdvanced ultra-high strength steels (A-UHSS) are revolutionizing both the steel and automotive industries, therefore it is imperative to study their hot plastic deformation behavior and modeling. The flow characteristics of all hot forming processes consist basically of two competitive phenomena: strain hardening and softening due to dynamic mechanisms (recovery and/or recrystallization). In this research work, the softening parameter was determined in a low carbon A-UHSS microalloyed steel with different amounts of boron (0, 14 and 214 ppm). Experimental stress–strain data of uniaxial hot-compression tests at different temperatures (950, 1000, 1050 and 1100 °C) and strain rates (10–3, 10–2 and 10–1 s–1) were used. The stress–strain relationships as a function of temperature and strain rate were described on the basis of the Estrin, Mecking, and Bergström model. The experimental values of the softening parameter Ω were adjusted using the least-squares method. In general, the results reveal that the softening parameter increases with increasing boron content.

1. For the diagnosis of electrolyte disorders, data on skeletal muscle composition are often valuable, but rarely available. We have therefore developed a simple and rapid needle biopsy procedure for the determination of the concentrations of K+, Na+, Mg2+ and Na+, K+-pumps in muscle. 2. Using a Bergström needle, biopsies weighing around 25 mg were taken from the vastus lateralis muscle of 18 normal subjects (aged 44–86 years) and extracted with trichloroacetic acid (TCA). The concentrations of K+, Na+ and Mg2+ were 90.7 ± 1.8, 31.9 ± 1.6 and 9.5 ± 0.2 μmol/g wet wt., respectively (means ± se). 3. The TCA extraction gave the same values as digestion with 65% HNO3 or 35% H2O2, could be used over the weight range 10–55 mg and showed a Mg2+ recovery of 101.7%. 4. The concentration of Na+, K+-pumps was quantified as the total capacity for [3H]ouabain binding. In vastus lateralis biopsies obtained from six normal subjects the mean value was 258 ± 16 pmol/g wet wt. 5. Comparison of the concentrations of K+, Mg2+ and [3H]ouabain-binding sites in samples obtained post mortem showed modest variation among different muscles with varying fibre composition. 6. Measurements of the concentrations of K+, Na+, Mg2+ and Na+, K+-pumps in duplicate biopsies of the vastus lateralis yield values which seem representative for the total pool of skeletal muscle fibres and can be performed within a few hours. 7. Measurements on patients receiving chronic diuretic treatment demonstrated that these procedures allow the detection of reduced levels of K+, Mg2+ and Na+, K+-pumps in skeletal muscle, as well as a partial recovery after oral Mg2+ supplementation.

Large eddy simulations (LES) are performed for single and multiphase jets in crossflow (JICF). The multiphase JICF are compared to the single-phase case for the same momentum and mass flow ratios but with droplets of different sizes. Multiphase JICF have stronger counterrotating vortex pairs (CVPs) than a corresponding single-phase JICF. Moreover, their trajectories are higher and their induced wakes weaker. The smaller the Stokes number of the droplets, the more the solution approaches the solution for single-phase flow. The computed results show the formation of a CVP and horseshoe vortices, which are convected downstream. LES also reveals the intermittent formation of upright wake vortices from the horseshoe vortices on the ground toward the CVP. The dispersion of polydisperse spray droplets is computed using the stochastic parcel method. Atomization and droplet breakup are modeled by a combination of the breakup model by Reitz and the Taylor analogy breakup model (see Caraeni, D., Bergström, C., and Fuchs, L., 2000, Flow, Turbul. Combust., 65(2), pp. 223–244). Evaporation and droplet collision are also modeled. The flow solver uses two-way coupling. Averages of the velocity and gaseous fuel mass fraction are computed. The single-phase JICF is validated against experimental data obtained by PIV. Additionally, the PDFs and frequency spectra are presented.

Abstract Kingsley, M. C. S., Wieland, K., Bergström, B., and Rosing, M. 2008. Calibration of bottom trawls for northern shrimp. – ICES Journal of Marine Science, 65: 873–881. The Skjervøy 3000 trawl used since 1988 in the West Greenland bottom-trawl survey has been replaced by a Cosmos 2000. To be able to compare old data on the northern shrimp (Pandalus borealis) with new data, calibration experiments were carried out by trawling twice consecutively along the same track, using either the same gear twice or the two different gears in one order or the other. Catch models were fitted to the shrimp data—both size-aggregated catch weights and size-specific counts—by likelihood and Bayesian methods. The catch in the second haul relative to that in the first depended not only on the gear used in the two hauls, but also on density, the second catches being a smaller proportion of first catches when densities were high, and often larger than the first catches at low-density stations. This density-dependence of the catch ratio was larger for small shrimp than for big ones. The Cosmos trawl was estimated to fish with ∼87% of the catchability of the Skjervøy trawl after correction for its greater wingspread. Catchability ratio varied with the size of shrimp caught, but the differences were not statistically significant.

Abstract. Optical properties of flame-generated black carbon (BC) containing soot particles were quantified at multiple wavelengths for particles produced using two different flames: a methane diffusion flame and an ethylene premixed flame. Measurements were made for (i) nascent soot particles, (ii) thermally denuded nascent particles, and (iii) particles that were coated and then thermally denuded, leading to the collapse of the initially lacy, fractal-like morphology. The measured mass absorption coefficients (MACs) depended on soot maturity and generation but were similar between flames for similar conditions. For mature soot, here corresponding to particles with volume-equivalent diameters >∼160 nm, the MAC and absorption Ångström exponent (AAE) values were independent of particle collapse while the single-scatter albedo increased. The MAC values for these larger particles were also size-independent. The mean MAC value at 532 nm for larger particles was 9.1±1.1 m2 g−1, about 17 % higher than that recommended by Bond and Bergstrom (2006), and the AAE was close to unity. Effective, theory-specific complex refractive index (RI) values are derived from the observations with two widely used methods: Lorenz–Mie theory and the Rayleigh–Debye–Gans (RDG) approximation. Mie theory systematically underpredicts the observed absorption cross sections at all wavelengths for larger particles (with x>0.9) independent of the complex RI used, while RDG provides good agreement. (The dimensionless size parameter x=πdp/λ, where dp is particle diameter and λ is wavelength.) Importantly, this implies that the use of Mie theory within air quality and climate models, as is common, likely leads to underpredictions in the absorption by BC, with the extent of underprediction depending on the assumed BC size distribution and complex RI used. We suggest that it is more appropriate to assume a constant, size-independent (but wavelength-specific) MAC to represent absorption by uncoated BC particles within models.

Abstract Objectives In this qualitative study, we examined the impact of the COVID-19 pandemic on motivations, decision-making, and food shopping among dollar store shoppers in Fresno, CA and Boston, MA. Eligible participants were ≥18 years old, lived in Boston or Fresno, spoke English or Spanish, and shopped at a dollar store within the past month. Methods Using convenience sampling, participants were recruited via flyers at 10 dollar stores in low-income neighborhoods in Fresno and Boston and posts in community Facebook groups. Interviews in Boston (n = 25) and Fresno (n = 26) were conducted remotely from August-December 2020. Results Our participants were primarily low-income, English-speaking women who shopped at dollar stores about once per week. Preliminary qualitative content analysis shows that key shopper motivations included low prices, product variety, and convenience. Shelf-stable foods and snacks were frequently purchased, especially for children. Shoppers in Fresno relied more on dollar stores for groceries and fresh produce, while Boston shoppers primarily purchased shelf-stable foods or snacks. Shoppers in both cities desired increased availability of fresh foods. Shoppers reported fear of shopping, limited stock, financial stress, and fewer trips early in the pandemic. Shopping increased by summer. Shoppers with children reported increased food expenditures during the pandemic, including at dollar stores, as closed schools meant that children consumed meals at home. Conclusions Dollar stores continue to be an important food resource despite challenges related to the pandemic. Considering frequent use, food purchases, and desire for more fresh foods among shoppers, dollar stores chains may find a receptive audience for increasing their fresh food stock. Funding Sources Ethical approval was provided by the Tufts University Social, Behavioral & Educational Research Institutional Review Board. Funding was provided by the Bergstrom Foundation and Tufts Friedman School of Nutrition Science and Policy.

Objective Our current programs (CPs) were compared to PD Adequest 2.0 (PD-A) for calculations of peritoneal membrane transport and dialysis adequacy. Design Thirty peritoneal equilibration tests (PETs) and 24-hour balances (24hBs) were conducted and calculated using our CPs and PD-A. Patients and Methods Thirty hospital-controlled peritoneal dialysis (PD) patients were studied. The inclusion of correction factors (for glucose or plasmatic water) and of residual volume, and the use of 3 or 6 peritoneal samples were analyzed to discover the differences between programs. The main outcome measures were peritoneal permeability and adequacy parameters, evaluated by Student t-test (mean and paired comparisons) and linear regression for correlation. Results No significant differences were found in D/P values for small solutes. At the first step, mass transfer area coefficient (MTAC) urea and MTAC creatinine were significantly higher in DP-A than in CP, but MTAC glucose did not differ. The causes of differences were: ( 1 ) inclusion of a correction factor for aqueous plasmatic concentration of small solutes in CP; ( 2 ) lack of inclusion of residual volume in peritoneal volumes in CP; and ( 3 ) use of 6 peritoneal samples in CP versus 3 in PD-A. At the second step, when the input data were made equivalent for both programs, the differences disappeared for MTAC urea, creatinine, and glucose (mean comparison), but creatinine and glucose remained different by paired comparison. Similar results were obtained when a correction for plasmatic aqueous concentration was applied to the data in both programs [MTAC urea: 22.60 ± 4.27 mL/min (CP) vs 22.43 ± 4.61 mL/min (PD-A), nonsignificant, r = 0.97; MTAC creatinine: 9.76 ± 3.83 mL/min (CP) vs 10.61 ± 3.07 mL/min (PD-A), nonsignificant, r = 0.98; MTAC glucose: 13.30 ± 3.12 mL/min (CP) vs 11.87 ± 3.41 mL/min (PD-A), nonsignificant, r = 0.92]. Creatinine and glucose were different by paired t-test. No significant differences were found in Kt/V and urea generation rate. Weekly creatinine clearance [WCCr: 70.71±16.71 L (CP) versus 79.33±18.73 L (PD-A), p < 0.001] and creatinine generation rate [CrGR: 0.56 ± 0.18 mg/min (CP) versus 0.61±0.19 mg/min (PD-A), p < 0.001) were significantly higher in PD-A than in CP owing to the lack of creatinine correction according to glucose concentration in the PD-A adequacy program. Finally, normalized protein nitrogen appearance according to Bergström [1.09 ± 0.20 g/kg/d (CP) versus 1.03 ± 0.21 g/kg/d (PD-A), p = 0.01] was different owing to the different algorithms and normalization method: standardized body weight in CP and actual body weight in PD-A. Conclusions Provided that equivalent data are used, PD-A and CP yield similar results. The PD-A program needs external correction of data input: ( 1 ) for plasmatic water concentration in MTAC calculations, and ( 2 ) for peritoneal glucose interference with creatinine analysis (Jaffé method) in WCCr and CrGR calculations; otherwise, it may give falsely optimistic results.

Background:Comparing drug effectiveness in observational settings is hampered by several major threats, among them confounding and attrition bias bias (patients who stop treatment no longer contribute information, which may overestimate true drug effectiveness).Objectives:To present points to consider (PtC) when analysing and reporting comparative effectiveness with observational data in rheumatology (EULAR-funded taskforce).Methods:The task force comprises 18 experts: epidemiologists, statisticians, rheumatologists, patients, and health professionals.Results:A systematic literature review of methods currently used for comparative effectiveness research in rheumatology and a statistical simulation study were used to inform the PtC (table). Overarching principles focused on defining treatment effectiveness and promoting robust and transparent epidemiological and statistical methods increase the trustworthiness of the results.Points to considerReporting of comparative effectiveness observational studies must follow the STROBE guidelinesAuthors should prepare a statistical analysis plan in advanceTo provide a more complete picture of effectiveness, several outcomes across multiple health domains should be comparedLost to follow-up from the study sample must be reported by the exposure of interestThe proportion of patients who stop and/or change therapy over time, as well as the reasons for treatment discontinuation must be reportedCovariates should be chosen based on subject matter knowledge and model selection should be justifiedThe study baseline should be at treatment initiation and a description of how covariate measurements relate to baseline should be includedThe analysis should be based on all patients starting a treatment and not limited to patients remaining on treatment at a certain time pointWhen treatment discontinuation occurs before the time of outcome assessment, this attrition should be taken into account in the analysis.Sensitivity analyses should be undertaken to explore the influence of assumptions related to missingness, particularly in case of attritionConclusion:The increased use of real-world comparative effectiveness studies makes it imperative to reduce divergent or contradictory results due to biases. Having clear recommendations for the analysis and reporting of these studies should promote agreement of observational studies, and improve studies’ trustworthiness, which may also facilitate meta-analysis of observational data.Disclosure of Interests:Delphine Courvoisier: None declared, Kim Lauper: None declared, Sytske Anne Bergstra: None declared, Maarten de Wit Grant/research support from: Dr. de Wit reports personal fees from Ely Lilly, 2019, personal fees from Celgene, 2019, personal fees from Pfizer, 2019, personal fees from Janssen-Cilag, 2017, outside the submitted work., Consultant of: Dr. de Wit reports personal fees from Ely Lilly, 2019, personal fees from Celgene, 2019, personal fees from Pfizer, 2019, personal fees from Janssen-Cilag, 2017, outside the submitted work., Speakers bureau: Dr. de Wit reports personal fees from Ely Lilly, 2019, personal fees from Celgene, 2019, personal fees from Pfizer, 2019, personal fees from Janssen-Cilag, 2017, outside the submitted work., Bruno Fautrel Grant/research support from: AbbVie, Lilly, MSD, Pfizer, Consultant of: AbbVie, Biogen, BMS, Boehringer Ingelheim, Celgene, Lilly, Janssen, Medac MSD France, Nordic Pharma, Novartis, Pfizer, Roche, Sanofi Aventis, SOBI and UCB, Thomas Frisell: None declared, Kimme Hyrich Grant/research support from: Pfizer, UCB, BMS, Speakers bureau: Abbvie, Florenzo Iannone Consultant of: Speaker and consulting fees from AbbVie, Eli Lilly, Novartis, Pfizer, Roche, Sanofi, UCB, MSD, Speakers bureau: Speaker and consulting fees from AbbVie, Eli Lilly, Novartis, Pfizer, Roche, Sanofi, UCB, MSD, Joanna KEDRA: None declared, Pedro M Machado Consultant of: PMM: Abbvie, Celgene, Janssen, Lilly, MSD, Novartis, Pfizer, Roche and UCB, Speakers bureau: PMM: Abbvie, BMS, Lilly, MSD, Novartis, Pfizer, Roche and UCB, Lykke Midtbøll Ørnbjerg Grant/research support from: Novartis, Ziga Rotar Consultant of: Speaker and consulting fees from Abbvie, Amgen, Biogen, Eli Lilly, Medis, MSD, Novartis, Pfizer, Roche, Sanofi., Speakers bureau: Speaker and consulting fees from Abbvie, Amgen, Biogen, Eli Lilly, Medis, MSD, Novartis, Pfizer, Roche, Sanofi., Maria Jose Santos Speakers bureau: Novartis and Pfizer, Tanja Stamm Grant/research support from: AbbVie, Roche, Consultant of: AbbVie, Sanofi Genzyme, Speakers bureau: AbbVie, Roche, Sanofi, Simon Stones Consultant of: I have been a paid consultant for Envision Pharma Group and Parexel. This does not relate to this abstract., Speakers bureau: I have been a paid speaker for Actelion and Janssen. These do not relate to this abstract., Anja Strangfeld Speakers bureau: AbbVie, BMS, Pfizer, Roche, Sanofi-Aventis, Robert B.M. Landewé Consultant of: AbbVie; AstraZeneca; Bristol-Myers Squibb; Eli Lilly & Co.; Galapagos NV; Novartis; Pfizer; UCB Pharma, Axel Finckh Grant/research support from: Pfizer: Unrestricted research grant, Eli-Lilly: Unrestricted research grant, Consultant of: Sanofi, AB2BIO, Abbvie, Pfizer, MSD, Speakers bureau: Sanofi, Pfizer, Roche, Thermo Fisher Scientific

Background:Comparative effectiveness studies using observational data are increasingly used. Despite their high potential for bias, there are no detailed recommendations on how these studies should best be analysed and reported in rheumatology.Objectives:To conduct a systematic literature review of comparative effectiveness research in rheumatology to inform the EULAR task force developing points to consider when analysing and reporting comparative effectiveness research with observational data.Methods:All original articles comparing drug effectiveness in longitudinal observational studies of ≥100 patients published in key rheumatology journals (Scientific Citation Index > 2) between 1.01.2008 and 25.03.2019 available in Ovid MEDLINE® were included. Titles and abstracts were screened by two reviewers for the first 1000 abstracts and independently checked to ensure sufficient agreement has been reached. The main information extracted included the types of outcomes used to assess effectiveness, and the types of analyses performed, focusing particularly on confounding and attrition.Results:9969 abstracts were screened, with 218 articles proceeding to full-text extraction (Figure 1), representing a number of rheumatic and musculoskeletal diseases. Agreement between the two reviewers for the first 1000 abstracts was 92.7% with a kappa of 0.6. The majority of the studies used several outcomes to evaluate effectiveness (Figure 2A). Most of the studies did not explain how they addressed missing data on the covariates (70%) (Figure 2B). When addressed (30%), 44% used complete case analysis and 10% last observation carried forward (LOCF). 25% of studies did not adjust for confounding factors and there was no clear correlation between the number of factors used to adjust and the number of participants in the studies. An important number of studies selected covariates using bivariate screening and/or stepwise selection. 86% of the studies did not acknowledge attrition (Figure 2C). When trying to correct for attrition (14%), 38% used non-responder (NR) imputation, 24% used LUNDEX1, a form of NR imputation, and 21% LOCF.Conclusion:Most of studies used multiple outcomes. However, the vast majority did not acknowledge missing data and attrition, and a quarter did not adjust for any confounding factors. Moreover, when attempting to account for attrition, several studies used methods which potentially increase bias (LOCF, complete case analysis, bivariate screening…). This systematic review confirms the need for the development of recommendations for the assessment and reporting of comparative drug effectiveness in observational data in rheumatology.References:[1]Kristensen et al. A&R. 2006 Feb;54(2):600-6.Acknowledgments:Support of the Standing Committee on Epidemiology and Health Services ResearchDisclosure of Interests:Kim Lauper: None declared, Joanna KEDRA: None declared, Maarten de Wit Grant/research support from: Dr. de Wit reports personal fees from Ely Lilly, 2019, personal fees from Celgene, 2019, personal fees from Pfizer, 2019, personal fees from Janssen-Cilag, 2017, outside the submitted work., Consultant of: Dr. de Wit reports personal fees from Ely Lilly, 2019, personal fees from Celgene, 2019, personal fees from Pfizer, 2019, personal fees from Janssen-Cilag, 2017, outside the submitted work., Speakers bureau: Dr. de Wit reports personal fees from Ely Lilly, 2019, personal fees from Celgene, 2019, personal fees from Pfizer, 2019, personal fees from Janssen-Cilag, 2017, outside the submitted work., Bruno Fautrel Grant/research support from: AbbVie, Lilly, MSD, Pfizer, Consultant of: AbbVie, Biogen, BMS, Boehringer Ingelheim, Celgene, Lilly, Janssen, Medac MSD France, Nordic Pharma, Novartis, Pfizer, Roche, Sanofi Aventis, SOBI and UCB, Thomas Frisell: None declared, Kimme Hyrich Grant/research support from: Pfizer, UCB, BMS, Speakers bureau: Abbvie, Florenzo Iannone Consultant of: Speaker and consulting fees from AbbVie, Eli Lilly, Novartis, Pfizer, Roche, Sanofi, UCB, MSD, Speakers bureau: Speaker and consulting fees from AbbVie, Eli Lilly, Novartis, Pfizer, Roche, Sanofi, UCB, MSD, Pedro M Machado Consultant of: PMM: Abbvie, Celgene, Janssen, Lilly, MSD, Novartis, Pfizer, Roche and UCB, Speakers bureau: PMM: Abbvie, BMS, Lilly, MSD, Novartis, Pfizer, Roche and UCB, Lykke Midtbøll Ørnbjerg Grant/research support from: Novartis, Ziga Rotar Consultant of: Speaker and consulting fees from Abbvie, Amgen, Biogen, Eli Lilly, Medis, MSD, Novartis, Pfizer, Roche, Sanofi., Speakers bureau: Speaker and consulting fees from Abbvie, Amgen, Biogen, Eli Lilly, Medis, MSD, Novartis, Pfizer, Roche, Sanofi., Maria Jose Santos Speakers bureau: Novartis and Pfizer, Tanja Stamm Grant/research support from: AbbVie, Roche, Consultant of: AbbVie, Sanofi Genzyme, Speakers bureau: AbbVie, Roche, Sanofi, Simon Stones Consultant of: I have been a paid consultant for Envision Pharma Group and Parexel. This does not relate to this abstract., Speakers bureau: I have been a paid speaker for Actelion and Janssen. These do not relate to this abstract., Anja Strangfeld Speakers bureau: AbbVie, BMS, Pfizer, Roche, Sanofi-Aventis, Robert B.M. Landewé Consultant of: AbbVie; AstraZeneca; Bristol-Myers Squibb; Eli Lilly & Co.; Galapagos NV; Novartis; Pfizer; UCB Pharma, Axel Finckh Grant/research support from: Pfizer: Unrestricted research grant, Eli-Lilly: Unrestricted research grant, Consultant of: Sanofi, AB2BIO, Abbvie, Pfizer, MSD, Speakers bureau: Sanofi, Pfizer, Roche, Thermo Fisher Scientific, Sytske Anne Bergstra: None declared, Delphine Courvoisier: None declared

Abstract Ultra-high molecular weight polyethylene (UHMWPE) used in biomedical applications, e.g. as a bearing surface in total joint arthroplasty, has to possess superior tribological properties, high mechanical strength, and toughness. Recently, equal channel angular extrusion (ECAE) was proposed as a processing method to introduce large shear strains to achieve higher molecular entanglement and superior mechanical properties of this material. Finite element analysis (FEA) can be utilized to evaluate the influence of important manufacturing parameters such as the extrusion rate, temperature, geometry of the die, back pressure, and friction effects. In this paper we present efficient FEA models of ECAE for UHMWPE. Our studies demonstrate that the choice of the constitutive model is extremely important for the accuracy of numerical modeling predictions. Three considered material models (J2-plasticity, Bergstrom-Boyce, and the Three Network Model) predict different extrusion loads, deformed shapes and accumulated shear strain distributions. The work has also shown that the friction coefficient significantly influences the punch force and that the 2D plane strain assumption can become inaccurate in the presence of friction between the billet and the extrusion channel. Additionally, a sharp corner in the die can lead to the formation of the so-called “dead zone” due to a portion of the material lodging into the corner and separating from the billet. Our study shows that the presence of this material in the corner substantially affects the extrusion force and the resulting distribution of accumulated shear strain within the billet

In October of 2020, a grower in Boyle County, KY, reported mold and blight symptoms on flowers of field-grown hemp. Plants were approaching harvest, and the mold was affecting 100% of the cultivar ‘White CBG’ being grown for cannabinoid (CBD) extraction. Mycelium colonized the flower heads and any seeds within bracts. Affected flower bracts were necrotic, and mycelium and necrosis in the most severe cases also encompassed adjacent (sugar) leaves. Necrotic symptomatic tissue was collected, disinfested in 10% bleach for one minute, and cultured on acidified potato dextrose agar (APDA). Each isolate was single-spored, transferred to PDA, stored in 15% glycerol at -80°C and maintained at room temperature under blacklight blue and fluorescent bulbs on a 12-hour light-dark cycle. Colonies produced white-pink mycelia with a dark red pigment on the undersides. Conidia collected after 7-9 days were falcate and septate (5 to 6). No microconidia were produced. Macroconidia measured 35.4-49.7 µm x 3.4-5.8 µm (n=50). The strains produced blue-black fertile perithecia on carrot agar when induced according to the method of (Bowden and Leslie, 1999). To confirm pathogenicity, flowers of hemp cultivars ‘Lifter’, ‘Trump Towers’, ‘Wife’ and ‘White CBG’ were inoculated in the greenhouse with a representative fungal strain (20Hemp010). Plants were inoculated at two different stages: when the styles were still green or after they had become senescent. Macroconidia were collected from 7- to 9-day-old cultures grown under a 12-hour light-dark cycle. Plants were spray-inoculated with a 5 x 105 per ml conidial suspension in 0.05% Tween 20 until runoff. Flower heads were individually covered with clear plastic bags and incubated for 72 h at 95-100% humidity under greenhouse benches to avoid direct light. Bags were removed after 72 h and returned to the bench. Greenhouse conditions were 23-25°C with a 14-hour photoperiod and 50% RH. Symptoms developed 7 dai in 1% of the flowers inoculated when styles were green, and 36% of the flowers that had senescent styles. Symptoms were similar to those initially noticed in Boyle County, including necrotic flower bracts and sugar leaves, and visible fungal growth. Symptoms were more severe on plants inoculated when styles were necrotic. Recovered fungi were morphologically similar to 20Hemp010. Genomic DNA was extracted from the mycelium with the Zymo Research Quick-DNA Fungal/Bacterial Miniprep Kit. A fragment of the translation elongation factor 1-alpha 1 gene was amplified with primers EF1 and EF2 as described by (O’Donnell et al. 1998). Amplicons were sequenced and the consensus (MZ407909) was compared with the NCBI GenBank Refseq database by BLASTn. The top hit was Fusarium graminearum with 100% identity (JF270185.1). Pairwise alignments via MycoBank Fusarium MLST and Fusarium-ID also revealed a top hit of F. graminearum with 100% identity (AY452957.1). Conidial and colony morphology were also consistent with F. graminearum (Leslie and Summerell, 2006), thus we conclude that this species was the causal agent of the flower blight and mold. The same disease was subsequently confirmed on hemp in Breathitt and Franklin Counties in KY in 2020. This is the first report of this disease in KY, although F. graminearum has been reported previously causing a similar flower blight on hemp in NY and NC (Bergstrom et al., 2019, Thiessen et al. 2020). Fusarium graminearum is common in KY as a cause of Fusarium head blight on wheat and Gibberella ear rot on corn. In cereals, fungal infection is facilitated by the production of the mycotoxin deoxynivalenol (DON), which is harmful to humans and livestock (Desjardins and Hohn, 1997). As hemp production in Kentucky continues to rise for production of CBD products and edible grains, accumulation and concentration of DON in these products could become a concern.

The paper develops an important method related to using algebraic inequalities for uncertainty and risk reduction and enhancing systems performance. The method consists of creating relevant meaning for the variables and different parts of the inequalities and linking them with real physical systems or processes. The paper shows that inequalities based on multivariable sub-additive functions can be interpreted meaningfully and the generated new knowledge used for optimising systems and processes in diverse areas of science and technology. In this respect, an interpretation of the Bergström inequality, which is based on a sub-additive function, has been used to increase the accumulated strain energy in components loaded in tension and bending. The paper also presents an interpretation of the Chebyshev’s sum inequality that can be used to avoid the risk of overestimation of returns from investments and an interpretation of a new algebraic inequality that can be used to construct the most reliable series-parallel system. The meaningful interpretation of other algebraic inequalities yielded a highly counter-intuitive result related to assigning devices of different types to missions composed of identical tasks. In the case where the probabilities of a successful accomplishment of a task, characterising the devices, are unknown, the best strategy for a successful accomplishment of the mission consists of selecting randomly an arrangement including devices of the same type. This strategy is always correct, irrespective of existing uknown interdependencies among the probabilities of successful accomplishment of the tasks characterising the devices.

Abstract Background and Aims S3 Physidia monitor is a dedicated system for short frequent hemodialysis at home based on push pull dialysis mode. Clinical data is provided to show the Beta 2 microglobulin elimination, used as a model for middle molecule removal. The aim of the study is to compare Beta 2 microglobulin removal between hemodialysis systems with low dialysate flow rate and conventional hemodialysis or hemodiafiltration. Method Analyzed data is collected during multicentric clinical study performed to evaluate the safety and performances level with S3 Physidia system. This clinical investigation has been conducted in accordance with the Good Clinical Practices (Helsinki Declaration), every patient was informed by the investigator and has signed the consent form prior to the completion of the study. The project has been approved by the local Committee and authorities. Anonymized data of 10 patients (age: 55.3 +/- 12.3 years, weight: 72.8 +/- 17.2 kg) is collected during 126 dialysis sessions (blood flow rate: 293 +/- 24 ml/min, dialysate flow rate: 190 +/- 14 ml/min). The convection volume (Ultrafiltration and back filtration generated by the push pull technique) is between 1 to 8 l per session (dialyzer used: Smartflux HFP190). For each session, Beta 2 microglobulin (β2M) removal rate is calculated by using pre and post dialysis β2M blood concentrations. Post concentration is corrected by using Bergström formula to take into account the hemoconcentration and rebound. Both single session (2hours) and weekly (12 hours/week) β2m removal rates were calculated. Single session and weekly β2m removal levels are compared to published data with conventional hemodialysis or post dilution hemodiafiltration. Weekly dialysis performance is evaluated according to the standardized Kt / V (sdt) according to the Gotch calculation method. Results Using S3 daily hemodialysis, weekly dialysis diffusive performance for urea (standardized Kt / V is 2.56 +/- 0.39, higher than KDIGO recommendations for frequent dialysis (min 2.1). β2M removal rate per session is 52.9 +/- 6.6 % with pre dialytic concentration average value of 25 mg/l corresponding to 73 mg of β2M removed per session. Calculated weekly β2M removal is 438 mg. These results are compared to β2M removal obtained by standard treatment procedures (ref1) and by short frequent hemodialysis using diffusive low dialysate flow (Nx Stage system One, ref 2). During conventional hemodialysis (4h, 3 sessions per week), the β2M removal rate is between 60 to 80 % corresponding to a removal of 300 to 380 mg/week (ref 1) During high volume post dilution hemofiltration (4h, 3 sessions per week, convection &gt; 20 l per session), the average β2M removal rate is 80% corresponding to a removal of 380 mg/week (ref 1) With Nx Stage device, without convective component, single session β2M removal rate is between 40 and 50 % depending on blood flow rate (maximum obtained with blood flow rate 400 ml/min) (ref 2) Ref 1: J. Potier et al, Int J Artif Organs. 2016 Nov 11;39(9):460-470 Ref 2 : M. Leclerc et al, Blood Purif 2018;46:279–285 Conclusion β2M reduction rate obtained with the S3 Physidia system is greater than 50%, removing any dowry concerning the performance of a low dialysate flow rate system. The convective component, provided by the push pull technique, must be confirmed, but these initial results are encouraging (reduction rate &gt; 50% despite a relatively low blood flow rate). Due to the frequency, the quantity of β2M weekly removed is higher than that obtained with conventional treatment methods.

Wandering the aisles of my local Woolworths in April this year, I noticed a large number of chocolate bilbies replacing chocolate rabbits. In these harsh economic times it seems that even the Easter bunny is in danger of losing his Easter job. While the changing shape of Easter chocolate may seem to be a harmless affair, the expulsion of the rabbit from Easter celebrations has a darker side. In this paper I look at the campaign to replace the Easter bunny with the Easter bilby, and the implications this mediated conservation move has for living rabbits in the Australian ecosystem. Essential to this discussion is the premise that studies of ecology must take into account the impact of media and culture on environmental issues. Of particular interest is the role of narrative, and the way the stories we tell about rabbits determine how they are treated in real life. While I recognise that the Australian bilby’s struggle for survival is a tale which should be told, I also argue that the vilification of the European-Australian rabbit is part of the native/invasive dualism which has ceased to be helpful, and has instead become a motivator of unproductive violence. In place of this simplified dichotomous narrative, I propose an ethic of "ecological remembrance" to combat the totalising eradication of the European rabbit from the Australian environment and culture. The Bilby vs the Bunny: A Case Study in "Media Selection" Easter Bunny says, ‘Bilby, I want you to have my job.You know about sharing and taking care.I think Australia should have an Easter Bilby.We rabbits have become too greedy and careless.Rabbits must learn from bilbies and other bush creatures’. The lines above are taken from Ali Garnett and Kaye Kessing’s children’s story, Easter Bilby, co-published by the Australian Anti-Rabbit Research Foundation as part of the campaign to replace the Easter bunny with the eco-politically correct Easter bilby. The first chocolate bilbies were made in 1982, but the concept really took off when major chocolate retailer Darrell Lea became involved in 2002. Since this time Haigh’s chocolate, Cadbury, and Pink Lady have also released delicious cocoa natives for consumption, and both Darrell Lea and Haigh’s use their profits to support bilby assistance programs, creating the “pleasant Easter sensation” that “eating a chocolate bilby is helping save the real thing” (Phillips). The Easter bilby campaign is a highly mediated approach to conservation which demonstrates the new biological principle Phil Bagust has recognised as “media selection.” Bagust observes that in our “hybridised global society” it is impossible to separate “the world of genetic selection from the world of human symbolic and material diversity as if they exist in different universes” (8). The Australian rabbit thrives in “natural selection,” having adapted to the Australian environment so successfully it threatens native species and the economic productivity of farmers. But the rabbit loses out in “cultural selection” where it is vilified in the media for its role in environmental degradation. The campaign to conserve the bilby depends, in a large part, on the rabbit’s failures in “media selection”. On Good Friday 2012 Sky News Australia quoted Mike Drinkwater of Wild Life Sydney’s support of the Easter bilby campaign: Look, the reason that we want to highlight the bilby as an iconic Easter animal is, number one, rabbits are a pest in Australia. Secondly, the bilby has these lovely endearing rabbit-like qualities. And thirdly, the bilby is a beautiful, iconic, native animal that is struggling. It is endangered so it’s important that we do all we can to support that. Drinkwater’s appeal to the bilby’s “endearing rabbit-like qualities” demonstrates that it is not the Australian rabbit’s individual embodiment which detracts from its charisma in Australian society. In this paper I will argue that the stories we tell about the European-Australian rabbit’s alienation from Indigenous country diminish the species cultural appeal. These stories are told with passionate conviction to save and protect native flora and fauna, but, too often, this promotion of the native relies on the devaluation of non-native life, to the point where individual rabbits are no longer morally considerable. Such a hierarchical approach to conservation is not only ethically problematic, but can also be ineffective because the native/invasive approach to ecology is overly simplistic. A History of Rabbit Stories In the Easter Bilby children’s book the illustrated rabbit offers to make itself disappear from the “Easter job.” The reason for this act of self-destruction is a despairing recognition of its “greedy and careless” nature, and at the same time, its selfless offer to be replaced by the ecologically conscious Bilby. In this sacrificial gesture is the implicit offering of all rabbit life for the salvation of native ecosystems and animal life. This plot line slots into a much larger series of stories we have been telling about the Australian environment. Libby Robin has observed that settler Australians have always had a love-hate relationship with the native flora and fauna of the continent (6), either devaluing native plants, animals, and ecosystems, or launching into an “overcompensating patriotic strut about the Australian biota” (Robin 9). The colonising dynamic of early Australian society was built on the devaluation of animals such as the bilby. This was reflected in the introduction of feral animals by “acclimatisation societies” and the privileging of “pets” such as cats and dogs over native animals (Plumwood). Alfred Crosby has made the persuasive argument that the invasion of Australia, and other “neo-European” countries, was, necessarily, more-than-human. In his work, Ecological Imperialism, Crosby charts the historical partnership between human European colonisers in Indigenous lands and the “grunting, lowing, neighing, crowing, chirping, snarling, buzzing, self-replicating and world-altering avalanche” (194) of introduced life that they brought with them. In response to this “guilt by association” Australians have reversed the values in the dichotomous colonial dynamic to devalue the introduced and so “empower” the colonised native. In this new “anti-colonial” story, rabbits signify a wound of colonisation which has spread across and infected indigenous country. J. M. Arthur’s (130) analysis of language in relation to colonisation highlights some of the important lexical characteristics in the rabbit stories we now tell. He observes that the rabbits’ impact on the county is described using a vocabulary of contamination: “It is a ‘menace’, a ‘problem’, an ‘infestation’, a ‘nuisance’, a ‘plague’” (170). This narrative of disease encourages a redemptive violence against living rabbits to “cure” the rabbit problem in order to atone for human mistakes in a colonial past. Redemptive Violence in Action Rabbits in Australia have been subject to a wide range of eradication measures over the past century including shooting, the destruction of burrows, poisoning, ferreting, trapping, and the well-known rabbit proof fence in Western Australia. Particularly noteworthy in this slaughter has been the introduction of biological control measures with the release of the savage and painful disease Myxomatosis in late December 1950, followed by the release of the Calicivirus (Rabbit Haemorrhage Disease, or RHD) in 1996. As recently as March 2012 the New South Wales Department of Primary Industries announced a 1.5 million dollar program called “RHD Boost” which is attempting to develop a more effective biological control agent for rabbits who have become immune to the Calicivirus. In this perverse narrative, disease becomes a cure for the rabbit’s contamination of Australian environments. Calicivirus is highly infectious, spreads rapidly, and kills rabbits en masse. Following the release of Calicivirus in 1995 it killed 10 million rabbits in eight weeks (Ponsonby Veterinary Centre). While Calicivirus appears to be more humane than the earlier biological control, Myxomatosis, there are indications that it causes rabbits pain and stress. Victims are described as becoming very quiet, refusing to eat, straining for breath, losing coordination, becoming feverish, and excreting bloody nasal discharge (Heishman, 2011). Post-mortem dissection generally reveals a “pale and mottled liver, many small streaks or blotches on the lungs and an enlarged spleen... small thrombi or blood clots” (Coman 173). Public criticism of the cruel methods involved in killing rabbits is often assuaged with appeals to the greater good of the ecosystem. The Anti-Rabbit research foundation state on their Website, Rabbit-Free Australia, that: though killing rabbits may sound inhumane, wild rabbits are affecting the survival of native Australian plants and animals. It is our responsibility to control them. We brought the European rabbit here in the first place — they are an invasive pest. This assumption of personal and communal responsibility for the rabbit “problem” has a fundamental blind-spot. Arthur (130) observes that the progress of rabbits across the continent is often described as though they form a coordinated army: The rabbit extends its ‘dominion’, ‘dispossesses’ the indigenous bilby, causes sheep runs to be ‘abandoned’ and country ‘forfeited’, leaving the land in ‘ecological tatters’. While this language of battle pervades rabbit stories, humans rarely refer to themselves as invaders into Aboriginal lands. Arthur notes that, by taking responsibility for the rabbit’s introduction and eradication, the coloniser assumes an indigenous status as they defend the country against the exotic invader (134). The apprehension of moral responsibility can, in this sense, be understood as the assumption of settler indigeneity. This does not negate the fact that assuming human responsibility for the native environment can be an act of genuine care. In a country scarred by a history of ecocide, movements like the Easter Bilby campaign seek to rectify the negligent mistakes of the past. The problem is that reactive responses to the colonial devaluation of native life can be unproductive because they preserve the basic structure of the native/invasive dichotomy by simplistically reversing its values, and fail to respond to more complex ecological contexts and requirements (Plumwood). This is also socially problematic because the native/invasive divide of nonhuman life overlays more complex human politics of colonisation in Australia. The Native/Invasive Dualism The bilby is currently listed as an “endangered” species in Queensland and as “vulnerable” nationally. Bilbies once inhabited 70% of the Australian landscape, but now inhabit less than 15% of the country (Save the Bilby Fund). This dramatic reduction in bilby numbers has multiple causes, but the European rabbit has played a significant role in threatening the bilby species by competing for burrows and food. Other threats come from the predation of introduced species, such as feral cats and foxes, and the impact of farmed introduced species, such as sheep and cattle, which also destroy bilby habitats. Because the rabbit directly competes with the bilby for food and shelter in the Australian environment, the bilby can be classed as the underdog native, appealing to that larger Australian story about “the fair go”. It seems that the Easter bilby campaign is intended to level out the threat posed by the highly successful and adaptive rabbit through promoting the bilby in the “cultural selection” stakes. This involves encouraging bilby-love, while actively discouraging love and care for the introduced rabbits which threaten the bilby’s survival. On the Rabbit Free Australia Website, the campaign rationale to replace the Easter bunny with the Easter bilby claims that: Very young children are indoctrinated with the concept that bunnies are nice soft fluffy creatures whereas in reality they are Australia’s greatest environmental feral pest and cause enormous damage to the arid zone. In this statement the lived corporeal presence of individual rabbits is denied as the “soft, fluffy” body disappears behind the environmentally problematic species’ behaviour. The assertion that children are “indoctrinated” to find rabbits love-able, and that this conflicts with the “reality” of the rabbit as environmentally destructive, denies the complexity of the living animal and the multiple possible responses to it. That children find rabbits “fluffy” is not the result of pro-rabbit propaganda, but because rabbits are fluffy! That Rabbit Free Australia could construe this to be some kind of elaborate falsehood demonstrates the disappearance of the individual rabbit in the native/invasive tale of colonisation. Rabbit-Free Australia seeks to eradicate the animal not only from Australian ecosystems, but from the hearts and minds of children who are told to replace the rabbit with the more fitting native bilby. There is no acceptance here of the rabbit as a complex animal that evokes ambivalent responses, being both worthy of moral consideration, care and love, and also an introduced and environmentally destructive species. The native/invasive dualism is a subject of sustained critique in environmental philosophy because it depends on a disjunctive temporal division drawn at the point of European settlement—1788. Environmental philosopher Thom van Dooren points out that the divide between animals who belong and animals who should be eradicated is “fundamentally premised on the reification of a specific historical moment that ignores the changing and dynamic nature of ecologies” (11). Mark Davis et al. explain that the practical value of the native/invasive dichotomy in conservation programs is seriously diminished and in some cases is becoming counterproductive (153). They note that “classifying biota according to their adherence to cultural standards of belonging, citizenship, fair play and morality does not advance our understanding of ecology” (153). Instead, they promote a more inclusive approach to conservation which accepts non-native species as part of Australia’s “new nature” (Low). Recent research into wildlife conservation indicates a striking lack of evidence for the case that pest control protects native diversity (see Bergstromn et al., Davis et al., Ewel & Putz, Reddiex & Forsyth). The problematic justification of “killing for conservation” becomes untenable when conservation outcomes are fundamentally uncertain. The mass slaughter which rabbits have been subjected to in Australia has been enacted with the goal of fostering life. This pursuit of creation through destruction, of re-birth through violent death, enacts a disturbing twist where death comes to signal the presence of life. This means, perversely, that a rabbit’s dead body becomes a valuable sign of environmental health. Conservation researchers Ben Reddiex and David M. Forsyth observe that this leads to a situation where environmental managers are “more interested in estimating how many pests they killed rather than the status of biodiversity they claimed to be able to protect” (715). What Other Stories Can We Tell about the Rabbit? With an ecological narrative that is failing, producing damage and death instead of fostering love and life, we are left with the question—what other stories can we tell about the place of the European rabbit in the Australian environment? How can the meaning ecologies of media and culture work in harmony with an ecological consciousness that promotes compassion for nonhuman life? Ignoring the native/invasive distinction entirely is deeply problematic because it registers the ecological history of Australia as continuity, and fails to acknowledge the colonising impact of European settlement on the environment. At the same time, continually reinforcing that divide through pro-invasive or pro-native stories drastically simplifies complex and interconnected ecological systems. Instead of the unproductive native/invasive dualism, ecologists and philosophers alike are suggesting “reconciliatory” approaches to the inhabitants of our shared environments which emphasise ecology as relational rather than classificatory. Evolutionary ecologist Scott P. Carroll uses the term “conciliation biology” as an alternative to invasion biology which focuses on the eradication of invasive species. “Conciliation biology recognises that many non-native species are permanent, that outcomes of native-nonnative interactions will vary depending on the scale of assessment and the values assigned to the biotic system, and that many non-native species will perform positive functions in one or more contexts” (186). This hospitable approach aligns with what Michael Rosensweig has termed “reconciliation ecology”—the modification and diversification of anthropogenic habitats to harbour a wider variety of species (201). Professor of Ecology and Evolutionary Biology Mark Bekoff encourages a “compassionate conservation” which avoids the “numbers game” of species thinking where certain taxonomies are valued above others and promotes approaches which “respect all life; treat individuals with respect and dignity; and tread lightly when stepping into the lives of animals”(24). In a similar vein environmental philosopher Deborah Bird Rose offers the term “Eco-reconciliation”, to describe a mode of “living generously with others, singing up relationships so that we all flourish” (Wild Dog 59). It may be that the rabbit cannot live in harmony with the bilby, and in this situation I am unsure of what a conciliation approach to ecology might look like in terms of managing both of these competing species. But I am sure what it should not look like if we are to promote approaches to ecology and conservation which avoid the simplistic dualism of native/invasive. The devaluation of rabbit life to the point of moral inconsiderability is fundamentally unethical. By classifying certain lives as “inappropriate,” and therefore expendable, the process of rabbit slaughter is simply too easy. The idea that the rabbit should disappear is disturbing in its abstract approach to these living, sentient creatures who share with us both place and history. A dynamic understanding of ecology dissipates the notion of a whole or static “nature.” This means that there can be no simple or comprehensive directives for how humans should interact with their environments. One of the most insidious aspects of the native/invasive divide is the way it makes violent death appear inevitable, as though rabbits must be culled. This obscures the many complex and contingent choices which determine the fate of nonhuman life. Understanding the dynamism of ecology requires an acceptance that nature does not provide simple prescriptive responses to problems, and instead “people are forced to choose the kind of environment they want” (189) and then take actions to engender it. This involves difficult decisions, one of which is culling to maintain rabbit numbers and facilitate environmental resilience. Living within a world of “discordant harmonies”, as Daniel Botkin evocatively describes it, environmental decisions are necessarily complex. The entanglement of ecological systems demands that we reject simplistic dualisms which offer illusory absolution from the consequences of the difficult choices humans make about life, ecologies, and how to manage them. Ecological Remembrance The vision of a rabbit-free Australia is unrealistic. As organisation like the Anti-Rabbit Research Foundation pursue this future ideal, they eradicate rabbits from the present, and seek to remove them from the past by replacing them culturally with the more suitable bilby. Culled rabbits lie rotting en masse in fields, food for no one, and even their cultural impact in human society is sought to be annihilated and replaced with more appropriate native creatures. The rabbits’ deaths do not turn back to life in transformative and regenerative processes that are ecological and cultural, but rather that death becomes “an event with no future” (Rose, Wild Dog 25). This is true oblivion, as the rabbit is entirely removed from the world. In this paper I have made a case for the importance of stories in ecology. I have argued that the kinds of stories we tell about rabbits determines how we treat them, and so have positioned stories as an essential part of an ecological system which takes “cultural selection” seriously. In keeping with this emphasis on story I offer to the conciliation push in ecological thinking the term “ecological remembrance” to capture an ethic of sharing time while sharing space. This spatio-temporal hospitality is focused on maintaining heterogeneous memories and histories of all beings who have impacted on the environment. In Deborah Bird Rose’s terms this is a “recuperative work” which commits to direct dialogical engagement with the past that is embedded in the present (Wild Country 23). In this sense it is a form of recuperation that promotes temporal and ecological continuity. Eco-remembrance aligns with dynamic understandings of ecology because it is counter-linear. Instead of approaching the past as a static idyll, preserved and archived, ecological remembrance celebrates the past as an ongoing, affective presence which is lived and performed. Ecological remembrance, applied to the European rabbit in Australia, would involve rejecting attempts to extricate the rabbit from Australian environments and cultures. It would seek acceptance of the rabbit as part of Australia’s “new nature” (Low), and aim for recognition of the rabbit’s impact on human society as part of dynamic multi-species ecologies. In this sense ecological remembrance of the rabbit directly opposes the goal of the Foundation for Rabbit Free Australia to eradicate the European rabbit from Australian environment and culture. On the Rabbit Free Australia website, the section on biological controls states that “the point is not how many rabbits are killed, but how many are left behind”. The implication is that the millions upon millions of rabbit lives extinguished have vanished from the earth, and need not be remembered or considered. However, as Deborah Rose argues, “all deaths matter” (Wild Dog 21) and “no death is a mere death” (Wild Dog 22). Every single rabbit is an individual being with its own unique life. To deny this is tantamount to claiming that each rabbit that dies from shooting or poisoning is the same rabbit dying again and again. Rose has written that “death makes claims upon all of us” (Wild Dog 19). These are claims of ethics and compassion, a claim that “we look into the eyes of the dying and not flinch, that we reach out to hold and to help” (Wild Dog 20). This claim is a duty of remembrance, a duty to “bear witness” (Wiesel 160) to life and death. The Nobel Peace Prize winning author, Elie Wiesel, argued that memory is a reconciliatory force that creates bonds as mass annihilation seeks to destroy them. Memory ensures that no life becomes truly life-less as it wrests the victims of mass slaughter from “oblivion” and allows the dead to “vanquish death” (21). In a continent inhabited by dead rabbits—a community of the dead—remembering these lost individuals and their lost lives is an important task for making sure that no death is a mere death. An ethic of ecological remembrance follows this recuperative aim. References Arthur, Jay M. The Default Country: A Lexical Cartography of Twentieth-Century Australia. Sydney: UNSW Press, 2003. Bagust, Phil. “Cuddly Koalas, Beautiful Brumbies, Exotic Olives: Fighting for Media Selection in the Attention Economy.” “Imaging Natures”: University of Tasmania Conference Proceedings (2004). 25 April 2012 ‹www.utas.edu.au/arts/imaging/bagust.pdf› Bekoff, Marc. “First Do No Harm.” New Scientist (28 August 2010): 24 – 25. Bergstrom, Dana M., Arko Lucieer, Kate Kiefer, Jane Wasley, Lee Belbin, Tore K. Pederson, and Steven L. Chown. “Indirect Effects of Invasive Species Removal Devastate World Heritage Island.” Journal of Applied Ecology 46 (2009): 73– 81. Botkin, Daniel. B. 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