Wohlfarth et al.: Rapid ecosystem response to abrupt climate changes during the last glacial period in Western Europe, kyr BP.

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1 1 GSA Data Repository Analytical Methods and Geochronology Tables DR1 and DR2 Figures DR1 and DR2 References Analytical Methods Whole core magnetic susceptibility (χ) was measured on split half cores at 5 mm resolution with a Bartington MS2EI point sensor core logger (at khz, with a low field intensity of 80 A/m). Dry density was calculated as the dry mass of the sample divided by its volume and is expressed as (g cm - 3 ). Grain-size distribution was determined by laser diffraction using a Fritsch A22 Laser Particle Sizer and is reported as sand (>63 μm), silt ( μm) and clay (<5.5 μm). For loss-on-ignition (LOI) analyses, the samples were dried at 105 C and combusted at 550 C. LOI is expressed as percentage loss of the original weight. TOC and TN elemental and isotopic (δ 13 C org ) compositions were determined on a Carlo Erba NC2500 elemental analyzer coupled with a Finnigan MAT Delta + mass spectrometer. Samples were treated with 2N HCl to remove carbonates prior to C org analyses, while TN was determined before carbonate removal. The relative error for both measurements was <1%. δ 13 C org is expressed as δ ( ) relative to the Vienna PeeDee Belemnite (VPDB) standard and measurement reproducibility is better than HI and OI contents were measured with a Rock-Eval Turbo 6 device (Lafargue et al., 1998). HI represents the hydrogenous products liberated per g of organic carbon (mg HC g -1 C org ) during the pyrolysis phase (between C), while OI represents mg of produced CO 2 per g of organic carbon (mgco 2 g -1 C org ) at temperatures below 390 C. BSi was determined using a wet alkaline extraction technique (DeMaster, 1981). Diatoms were separated by standard methods and at most levels a minimum of 400 diatom valves was counted. Planktonic and benthic diatom abundances are expressed as percentages relative to the total number of counted valves. Samples for pollen analysis were prepared for pollen identification following Goeury and de Beaulieu (1979). The mean pollen sum ranges between 250 and 450.

2 2 AMS radiocarbon dating A total of 48 AMS 14 C measurements were obtained on plant macrofossils, pollen and the insoluble bulk sediment fraction (Table DR1). Samples containing plant remains were prepared by wet sieving of the sediment and collection of plant macrofossils under a binocular microscope. Plant remains were acidified (10% HCl), cleaned with distilled water and dried in pre-cleaned (distilled water) glass vials at 105 C overnight. The dried samples were then submitted to radiocarbon laboratories, where pretreatment procedures varied slightly. At the Lund Radiocarbon Laboratory (LuS) plant macrofossil samples with <4 mg weight were not pre-treated, while samples >4 mg weight were pre-treated as follows: 0.5% NaOH at room temperature for 0.5 hours, followed by HCl at 80 C for 1 hour, rinsing with distilled water and drying at 105 C overnight. The insoluble (INS) fraction was pre-treated with 2% HCl at 80 C overnight, followed by 2% NaOH at 80 C for 5 hours. At the Poznań (Poz- ) and Uppsala (Ua- ) Radiocarbon Laboratories samples were subjected to an acid-alkali-acid treatment that consisted of 1% HCl for 8-10 hours just below the boiling point, 0.5% NaOH for 1 hour at 60 C, and acidification to ph 3 (Table DR1). δ 13 C was measured in a conventional mass spectrometer (VG OPTIMA) only on a few selected samples. Pollen and spores were isolated from sediment samples following chemical and micro-sieving methods (Brown et al., 1989, 1992; Regnel, 1992; Brown, 1994): treatment with 10% KOH, 10% HCl, sieving of residue at 100 μm, HF, 10% HCl, 2% NaOCl, sieving of residue at 20 μm, and H 2 SO 4. The resulting pollen concentrate consisted primarily of bisaccate conifer pollen. Pollen concentrates were rinsed with distilled water and dried at 105 C overnight prior to graphitization at the radiocarbon laboratory. The δ 13 C results show that samples labelled plant detritus were mainly composed of limnic plant material (δ 13 C -11 to -20 ), although some samples also contained terrestrial plant material (δ 13 C >20 ) (Table DR1). Limnic plant material from hard water lakes is prone to a hard-water effect since limnic plants take up carbon from the ambient lake water during photosynthesis. However in the case of Les Echets we judged that this effect is negligible except for Poz-2492, because (i) pollen concentrates from comparable levels resulted in similar age determinations; and (ii) the 95% confidence interval of the measurements is larger than the hypothetical hard water error (Björck and Wohlfarth, 2001).

3 3 Infrared stimulated luminescence dating Sampling and preparation for infrared stimulated luminescence (IRSL) dating was carried out under subdued red-light conditions. The outer parts of the half-cores were removed and the inner part that was not exposed to daylight was sampled for dating. Altogether, 32 samples were removed from Core EC 1 from which 21 have been investigated so far (Fig. DR1, Table DR2). The polymineral fine grain fraction (4-11 µm) was extracted after chemical pre-treatments (HCl, H 2 O 2, Na-Oxalate) by settling using Stokes' law. The silt fraction was used because sufficient amounts of sand size grains were not available in the lacustrine deposits. We did not attempt to extract the quartz fraction from the samples since usually this mineral has poor luminescence properties in areas around young orogenic systems, such as the Alps (Klasen et al., 2006; Preusser et al., 2006). However, previous experience suggests that K-feldspars, which will dominate the investigated IRSL signal from polymineral fine grains, are a reliable natural dosimeter in the Alpine realm (Preusser, 2003; Preusser et al., 2003; Preusser and Schlüchter, 2004). Determination of D E was carried out using the modified single-aliquot regenerative-dose (SAR) protocol (Preusser, 2003) (Fig. DR2). A preheat temperature of 290 C and a cut heat of 200 C were applied. This procedure was crosschecked by preheat and dose recovery tests, applying a dose of the same magnitude as the natural dose. The average ratio of applied/regenerated dose for the investigated samples is 1.04 ± Measurements were carried out using Risø TL/OSL readers. The detection filter was a combination of a Schott BG-39, a Schott GG400, and a Corning 7-59 giving a peak emission at ~410 nm. IRSL was recorded during a 300 s shine-down of IR-diodes (Fig. DR2). The integral s was subtracted from the rest of the IRSL decay curves as late-light and the signal of the first 5 s was used for constructing dose response curves (Fig. DR2). All samples showed recycling ratios close to 1.00 and low recuperation (3-4%). At least seven aliquots were measured for each sample. The plot of D E versus stimulation time shows a flat plateau (Fig. DR2). This is one indication of complete bleaching of IRSL prior to deposition. Furthermore, many previous studies have demonstrated that lacustrine samples are usually well bleached (Doran et al., 1999; Wolfe et al., 2000; Berger and Doran, 2001; Lang and Zolitschka, 2001; Berger et al., 2004; Preusser et al., 2005; Vandergoes et al., 2005). Although optical dating of feldspar from some regions seems to systematically underestimate the known age of a sample due to fading of the luminescence signal, previous luminescence dating in the Alpine region (Preusser, 1999, 2003; Viscoceaks and Guérin, 2006) indicates that feldspars from these areas are not affected by this phenomenon.

4 4 Dose rate relevant elements of all samples were determined by ICP-MS (Preusser and Kasper, 2001) using updated conversions factors (Adamiec and Aitken, 1998). The validity of the analytic procedures was cross-checked by measuring certified reference material. The samples could not be tested for radioactive equilibrium due to the limited amount of material available for high-resolution gamma spectrometry. However, sediments such as the silts investigated in the present study are usually not significantly affected by radioactive disequilibrium (Lang and Zolitschka, 2001; Thomas et al., 2003; Preusser et al., 2005). The contribution from cosmic rays to the total dose rate was calculated using present day depth (Prescott and Hutton, 1994). Dose rates were determined using a mean a-value (Preusser, 1999) of 0.07 ± Present day moisture was used for calculating the effect of attenuation of radioactive radiation by water in the sediment pores. Past changes in water content are seen as the major source of uncertainty in IRSL dating at Les Echets. Due to the consolidation of lacustrine sediments, it is likely that average moisture in the past was higher than today. As a consequence, we consider all IRSL ages as minimum estimates but it is expected that the true age of a sample may not differ by more than 10% from the given calculation (Juchus et al., 2007). Age model construction Because most of the 14 C dates of Les Echets core EC 1 fall beyond the oldest ages of the internationally agreed IntCal04 calibration curve (Reimer et al., 2004), we evaluated alternative comparison (van der Plicht et al., 2004) curves (Kitagawa and van der Plicht, 1998; Beck et al., 2001; Fairbanks et al., 2005; Hughen et al., 2006) before computing an age model. We chose the updated calibration data set of (Hughen et al., 2006), which is based on a match between the Cariaco Basin 14 C chronology and the 230 Th-dated Hulu Cave speleothem records. Despite the increased resolution offered by this updated calibration set, it has not yet been securely anchored to known calendar years and its 14 C dates suffer from an imprecisely known and possibly varying marine reservoir effect. Therefore we refrain from using the term calibration (van der Plicht et al., 2004) and refer to calendar ages as Age (years BP). Although we are aware of the limitations of our age model, it is the best option with the data and methods presently available. In total 48 AMS 14 C dates (Table DR1) and 21 IRSL dates (Table DR2) were used to build the age model, which was constrained by the following prior information, using the Bayesian software Bpeat (Blaauw and Christen, 2005): i) the depositional setting dictates that the dated depths must be ordered chronologically; ii) deposition rates of 5-15 years/cm are most likely, but other accumulation rates are

5 5 possible (AlphaM 12, AlphaStd 4) (Blaauw and Christen 2005); iii) the variable stratigraphy suggests that rapid accumulation rate changes and hiatuses could have occurred (Epsilon 3) (Blaauw et al., 2007); iv) hiatuses are most likely to be very short, but could at times last millennia (HiatusA , HiatusB ) (Blaauw and Christen, 2005); and v) every date has a prior probability of being an outlier (5% for most 14 C dates; 20% for all IRSL dates and for those 14 C dates which could not be pretreated, had a sample weight <1 mg or were possibly altered by a hard-water effect; Table DR1). We applied 66 section breaks to obtain an age model based on linear interpolation between (IRSL or 14 C) dated levels, constrained by the prior information stated above. The 14 C dates were translated into calendar ages using the Cariaco comparison curve (Hughen et al., 2006), while the IRSL dates were already in calendar ages and were included as reported. We ran >1 billion Monte Carlo Markov Chain iterations (Blaauw and Christen, 2005) in order to find the best age model. Although most 14 C dates were placed on the comparison curve, many IRSL dates differ greatly from their given calendar ages and this reflects their large uncertainty range. Outlying dates were not removed but were identified and down-weighted automatically (Blaauw and Christen, 2005). The independent chronology for the Les Echets sequence permits a direct comparison between our palaeoenvironmental proxies and other independently-dated records such as the δ 18 O record for NorthGRIP (Andersen et al., 2006) without having to resort to tuning or wiggle-matching. References Adamiec, G., and Aitken, M.J., 1998, Dose-rate conversion factors: update: Ancient TL, v.16, p Andersen, K.K., Svensson, A., Rasmussen, S.O., Steffensen, J.P., Johnsen, S.J., Bigler, M., Röthlisberger, R., Ruth, U., Siggaard-Andersen, M.-L., Dahl-Jensen, D., Vinther, B.M., and Clausen, H.B., 2006, The Greenland Ice Core Chronology 2005, ka. Part 1: constructing the time scale: Quaternary Science Reviews, v. 25, p Beck, J.W., Richards, D.A., Edwards, R.L., Silverman, B.W., Smart, P.L., Donahue, D.J., Hererra- Osterheld, S., Burr, G.S., Calsoyas, L., Jull, A.J.T., and Biddulph, D., 2001, Extremely large variations of atmospheric 14 C concentration during the Last Glacial period: Science, v. 292, p Berger, G.W., and Doran, P.T., 2001, Luminescence-dating zeroing tests in Lake Hoare, Taylor Valley, Antarctica: Journal of Paleolimnology, v. 25, p

6 6 Berger, G.W., Melles, M., Banerjee, D., Andrew S. Murray, A.S., and Raab, A., 2004, Luminescence chronology of non-glacial sediments in Changeable Lake, Russian High Arctic, and implications for limited Eurasian ice-sheet extent during the LGM: Journal of Quaternary Science, v. 19, p Björck, S., and Wohlfarth, B., 2001, 14 C chronostratigraphic techniques in paleolimnology, in Last, W.M., and Smol, J.P., eds., Tracking environmental change using lake sediments: Basin analysis, coring and chronological techniques: Kluwer Academic Publishers, Dordrecht, p Blaauw, M., and Christen, J.A., 2005, Radiocarbon and peat chronologies and environmental change: Applied Statistics, v. 54, p Blaauw, M., Bakker, R., Christen, J.A., Hall, V.A., and van der Plicht, J., 2007, Bayesian framework for age-modelling of radiocarbon dated peat deposits: case studies from the Netherlands: Radiocarbon, v. 49, p Brown, T.A., 1994, Radiocarbon dating of pollen by accelerator mass spectrometry: Ph.D. Thesis, University of Washington. Brown, T.A., Nelson, D.E., Mathewes, R.W., Vogel, J.S., and Southon, J.R., 1989, Radiocarbon dating of pollen by accelerator mass spectrometry: Quaternary Research, v. 32, p Brown, T.A., Farwell, G.W., Grootes, P.M., and Schmidt, F.H., 1992, Radiocarbon AMS dating of pollen extracted from peat samples: Radiocarbon, v. 34, p DeMaster, D.J., 1981, The supply and accumulation of silica in the marine environment. Geochimica et Cosmochimica Acta, v. 45, p , doi: / (81) Doran, P.T., Berger, G.W., Lyons, W.B., Wharton, R.A., Davisson, M.L., Southon, J., and Dibb, J.E., 1999, Dating Quaternary lacustrine sediments in the McMurdo Dry Valleys, Antarctica: Palaeogeography, Palaeoclimatology, Palaeoecology, v. 147, p Fairbanks, R.G., Mortlock, R.A., Chiu, T.-C., Cao, L., Kaplan, L.A., Guilderson, T.P., Fairbanks, T.W., Bloom, A.L., Grootes, P.M., and Nadeau, M.-J., 2005, Radiocarbon calibration curve spanning 0 to 50,000 years BP based on paired 230 Th/ 234 U/ 238 U and 14 C dates on pristine corals: Quaternary Science Reviews, v. 24, p Goeury, C., and de Beaulieu, J.-L., 1979, A propos de la concentration du pollen à l aide de la liqueur de Thoulet dans les édiments mineraux: Pollen et Spores, v. XXI, p

7 7 Hughen, K., Southon, J., Lehman, S., Bertrand, C., and Turnbull, J., 2006, Marine-derived 14 C calibration and activity record for the past 50,000 years updated from the Cariaco Basin: Quaternary Science Reviews, v. 25, p Juschus, O., Preusser, F., Melles, M., and Radtke, U., 2007, Applying SAR-IRSL methodology for dating fine-grained sediments from Lake El'gygytgyn, north-eastern Siberia: Quaternary Geochronology, v. 2, p Kitagawa, H., and van der Plicht, J., 1998, Atmospheric radiocarbon calibration to 45,000 yr B.P.: Late Glacial fluctuations and cosmogenic isotope production: Science, v. 279, p Klasen, N., Preusser, F., Fiebig, M., Blei, A., and Radtke, U., 2006, Luminescence properties of glaciofluvial sediments from the Bavarian Alpine Foreland: Radiation Measurements, v. 41, p Lafarque, E., Marquis, F., and Pillot, D., 1988, Rock-Eval 6 applications in hydrocarbon exploration, production, and soil contamination studies. Révue de l Institut Français du Pétrol, v. 53, p Lang, A., and Zolitschka, B., 2001, Optical dating of annually laminated lake sediments: A test case from Holzmaar/Germany: Quaternary Science Reviews, v. 20, p van der Plicht, J., Beck, J.W., Bard, E., Baillie, M.G.L., Blackwell, P.G., Buck, C.E., Friedrich, M., Guilderson, T.P., Hughen, K.A., Kromer, B., McCormac, F.G., Bronk Ramsey, C., Reimer, P.J., Reimer, R.W., Remmele, S., Richards, D.A., Southon, J.R., Stuiver, M., and Weyhenmeyer, C.E., 2004, Notcal04-Comparison/Calibration 14 C records cal kyr BP: Radiocarbon, v. 48, p Prescott, J.R., and Hutton, J.T., 1994, Cosmic ray contributions to dose rates for luminescence and ESR dating: large depth and long time variations: Radiation Measurements, v. 23, p Preusser, F., 1999, Lumineszenzdatierung fluviatiler Sedimente - Fallbeispiele aus der Schweiz und Norddeutschland: Kölner Forum für Geologie und Paläontologie, v. 3, 63 pp. Preusser, F., and Kasper, H.U., 2001, Comparison of dose rate determination using high-resolution gamma spectrometry and inductively coupled plasma-mass spectrometry: Ancient TL, v. 19, p Preusser, F., 2003, IRSL dating of K-rich feldspars using the SAR protocol: Comparison with independent age control: Ancient TL, v. 21, p

8 8 Preusser, F., Geyh, M.A., and Schlüchter, C., 2003, Timing of Late Pleistocene climate change in lowland Switzerland: Quaternary Science Reviews, v. 22, p Preusser F., and Schlüchter, C., 2004, Dates from an important early Late Pleistocene ice advance in the Aare Valley, Switzerland: Eclogae Geologicae Helvetiae, v. 97, p Preusser, F., Drescher-Schneider, R., Fiebig, M., and Schlüchter, C., 2005, Re-interpretation of the Meikirch pollen record, Swiss Alpine Foreland, and implications for Middle Pleistocene chronostratigraphy: Journal of Quaternary Science, v. 20, p Preusser, F., Ramseyer, K., and Schlüchter, C., 2006, Characterisation of low luminescence intensity quartz from Westland, New Zealand: Radiation Measurements, v. 41, p Regnell, J., 1992, Preparing pollen concentrates for AMS dating: a methodological study from a hard-water lake in southern Sweden: Boreas, v. 21, p Reimer, P.J., Baillie, M.G.L., Bard, E., Bayliss, A., Beck, J.W., Bertrand, C.J.H., Blackwell, P.G., Buck, C.E., Burr, G.S., Cutler, K.B., Damon, P.E., Edwards, R.L., Fairbanks, R.G., Friedrich, M., Guilderson, T.P., Hogg, A.G., Hughen, K.A., Kromer, B., McCormac, F.G., Manning, S.W., Ramsey, C.B., Reimer, R., Remmele, S., Southon, J. R., Stuiver, M., Talamo, S., Taylor, F.W., van der Plicht, J., and Weyhenmeyer, C.E., 2004, IntCal04 terrestrial radiocarbon age calibration, 26-0 ka BP: Radiocarbon, v. 46, p Thomas, P.J., Murray, A.S., and Sandgren, P., 2003: Age limit and age underestimation using different OSL signal from lacustrine quartz and polymineral fine grains: Quaternary Science Reviews, v. 22, p Vandergoes, M., Newnham, R., Preusser, F., Hendy, C., Lowell, T., Fitzsimons, S., Hogg, A., Kasper, H.U., and Schlüchter, C., 2005, Southern Ocean terrestrial record showing local modification of glacial-interglacial climate signals: Nature, v. 436, p Visocekas, R., and Guérin, G., 2006, TL dating of feldspars using their far-red emission to deal with anomalous fading: Radiation Measurements, v. 41, p

9 9 TABLE DR1. AMS 14 C MEASUREMENTS ON LES ÉCHETS CORE EC 1 Lab ID Depth Material Sample Pre-treatment δ 13 C 14 C yr BP (cm) dated weight (mg) (±1s) Poz ±3 Plant detritus 19 HCl, NaOH, HCl ,090±90# LuS ±0.5 Plant detritus ,310±160* LuS ±0.5 Plant detritus ,100±400* LuS ±1 Plant detritus ,030±140* LuS ±0.5 Plant remains 8 NaOH, HCl -- 22,625±120 LuS ±0.5 Plant remains 5 NaOH, HCl -- 22,210±120 LuS ±1 Plant remains 8 NaOH, HCl -- 23,175±105 Poz ±0.5 Plant remains 48 HCl, NaOH, HCl -12,3 23,890±150 LuS ±1 Pollen 4 Rinsed with dist. H 2 O -- 23,500±150 LuS ±0.5 Plant remains 8 NaOH, HCl -- 24,490±170 LuS ±0.5 Plant remains ,090±170* LuS ±0.5 Plant remains 15 NaOH, HCl -- 23,820±140 LuS ±0.5 Plant remains 13 NaOH, HCl -- 24,945±120 LuS ±0.5 Plant remains 9 NaOH, HCl -- 24,350±250 Ua ±0.5 Plant remains 1.5 HCl, NaOH, HCl -12,4 24,310±470 LuS ±0.5 Plant remains 10 NaOH, HCl -- 24,725±140 LuS ±0.5 Plant remains ,455±210* Ua ±0.5 Plant remains 2.3 HCl, NaOH, HCl -15,6 26,115±195 LuS ±1 Sediment/INS >50 HCl, NaOH -- 27,700±250 Ua ±0.5 Plant remains 0.5 HCl, NaOH, HCl -21,5 21,245±220* LuS ±1 Sediment/INS >50 HCl, NaOH -- 30,850±350 LuS ±1 Pollen 4 Rinsed with dist. H 2 O -- 23,200±150 LuS ±1 Sediment/INS >50 HCl, NaOH -- 30,150±400 LuS ±1 Sediment/INS >50 HCl, NaOH -- 28,600±300 LuS ±1 Pollen 12 Rinsed with dist. H 2 O -- 28,800±300 LuS ±1 Sediment/INS >50 HCl, NaOH -- 29,450±300 Ua ±1 Plant remains 2.4 HCl, NaOH, HCl -25,9 30,005±190 LuS ±1 Pollen 6 Rinsed with dist. H 2 O -- 26,950±200 LuS ±1 Plant remains ,600±500* LuS ±1 Pollen 4 Rinsed with dist. H 2 O -- 29,750±200 Ua ±0.5 Plant remains 1.8 HCl, NaOH, HCl -13,2 30,705±195 Ua ±1 Plant remains 2.5 HCl, NaOH, HCl -22,8 31,200±350

10 10 TABLE DR1 (continued). AMS 14 C MEASUREMENTS ON LES ÉCHETS CORE EC 1 Lab ID Depth Material Sample Pre-treatment δ 13 C 14 C yr BP (cm) dated weight (mg) (±1s) LuS ±1 Pollen 13 Rinsed with dist. H 2 O -- 27,400±200 LuS ±1 Pollen 12 Rinsed with dist. H 2 O -- 31,200±350 Ua ±1 Plant remains 1.7 HCl, NaOH, HCl -11,1 30,815±340 Ua ±1 Plant remains 2.3 HCl, NaOH, HCl -16,1 32,010±225 LuS ±2 Pollen 4 Rinsed with dist. H 2 O -- 31,950±250 LuS ±1 Pollen 12 Rinsed with dist. H 2 O -- 31,800±350 LuS ±0.5 Sediment/INS 10 HCl, NaOH -- 32,700±400 LuS ±0.5 Plant remains ,450±700* Ua ±0.5 Plant remains 2.3 HCl, NaOH, HCl -16,9 35,300±365 LuS ±1 Sediment/INS >50 HCl, NaOH -- 39,400±1400 LuS ±0.5 Sediment/INS 10 HCl, NaOH -- 40,000±800 LuS ±0.5 Sediment/INS 3 HCl, NaOH -- 42,200±1000 LuS ±1 Sediment/INS >50 HCl, NaOH -- >45,000** LuS ±1 Sediment/INS >50 HCl, NaOH -- >40,000** LuS ±1 Sediment/INS >50 HCl, NaOH -- 38,550±1300 LuS ±0.5 Plant remains ,320±600* INS is the insoluble fraction. Sample weight is reported after laboratory pre-treatment. # Sample treated as a potential outlier in Bpeat because we suspected that it might have been influenced by a hard water effect. * Samples treated as potential outliers in Bpeat, because their weight was < 1mg and/or they were not subjected to pre-treatment, which increases the risk of contamination. ** Samples not included in the age model because the measurements gave infinite ages.

11 11 TABLE DR2. IRSL MEASUREMENTS ON LES ÉCHETS CORE EC 1 Depth K Th U D ED Age Sample (cm) (%) (ppm) (ppm) (Gy kyr -1 ) (Gy) (kyr) LE ± ± ± ± ± ± 3.2 LE ± ± ± ± ± ± 3.1 LE ± ± ± ± ± ± 2.7 LE ± ± ± ± ± ± 3.0 LE ± ± ± ± ± ± 3.2 LE ± ± ± ± ± ± 3.0 LE ± ± ± ± ± ± 4.3 LE ± ± ± ± ± ± 3.7 LE ± ± ± ± ± ± 3.8 LE ± ± ± ± ± ± 3.8 LE ± ± ± ± ± ± 6.3 LE ± ± ± ± ± ± 4.4 LE ± ± ± ± ± ± 4.4 LE ± ± ± ± ± ± 5.3 LE ± ± ± ± ± ± 5.0 LE ± ± ± ± ± ± 6.0 LE ± ± ± ± ± ± 9.0 LE ± ± ± ± ± ± 9.2 LE ± ± ± ± ± ± 11.8 LE ± ± ± ± ± ± 13.0

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