Assuming that the first Chilia lobe was partially built during it

Assuming that the first Chilia lobe was partially built during its first depositional cycle, the estimated rate of sediment deposition for the entire lobe must have been less than 5.9 MT/year (see Supplementary data). Subsequently, during the Chilia II lobe growth to completion, the depositional rate remained similar PD0332991 solubility dmso at ∼4.5 MT/year but it increased by an order of magnitude to over 60 MT/year during the open coast Chilia III lobe growth phase (Table 2 in Supplementary data). Thus, Danube’s partial avulsion that reactivated

the Chilia branch was gradual since the 8th century BC and its discharge reached its maximum only around 1700 AD. This sustained increase in sediment load brought down by the Danube to the delta was explained by Giosan et al. (2012) by an increase in erosion in the lower watershed. Ecological changes in the Black Sea best constrain the age of the maximum sediment load to the last 700–600 years, when an upsurge in soil-derived nutrients (i.e., Si, N) lead to the makeover of the entire marine ecosystem (Giosan et al., 2012 and Coolen et al., 2013). Past hydroclimate changes in

the lower Danube basin are currently little known but detailed reconstructions in the Alps (Glur et al., 2013) document repeated intervals of higher precipitation in the last thousand years associated with cooler periods in Central Europe (Büntgen et al., 2011). Stronger and higher floods during this period may help explain the successive Danube avulsions, first toward the St George, and then toward the Chilia branch. However, the lack of a strong sensitivity to changes in discharge in a large river like Danube (McCarney-Castle et al., 2012) leaves the dramatic increase in sediment load unexplained without a late deforestation

of the lower watershed (Giosan et al., 2012), which provides the bulk of the Danube’s load (McCarney-Castle et al., 2012). Similar increased sensitivity to land use for continental scale rivers have been documented in other cases, whether through modeling (e.g., for Ebro River by Xing et al., 2014) or field-based studies (e.g., Rhine GPX6 by Hoffmann et al., 2009). However, climate variability expressed as floods probably contributed to this intense denudation as the erosion sensitivity of landscapes increases on deforested lands (Lang et al., 2003). What could explain the rapid deforestation in the lower Danube basin since the 15th century (Giurescu, 1976), hundreds of years later than in the upper watershed of Central Europe (Kaplan et al., 2009)? The Columbian Exchange (Crosby, 2003), which led to the adoption of more productive species such as maize probably led to “a demographic revival” ( White, 2011), which certainly required the expansion of agricultural lands. However, this alone cannot explain the extensive clearing of forest in agriculturally marginal highlands of the Carpathian and Balkan mountain ranges (e.g., Feurdean et al., 2012).

As the formed clusters and particles were polydisperse (>30% in s

As the formed clusters and particles were polydisperse (>30% in some cases), cluster sizes derived from DLS are only interpreted as trends (van Leeuwen et al., 2012b). Samples were dried on a carbon-coated copper grid prior to transmission electron microscopy (TEM) performed on a Tecnai 12 or scanning electron

microscopy (SEM) using a Phenom scanning electron microscope, both from FEI Company. All samples for spectrophotometry were prepared to contain the same concentration of iron (0.7 mM). Samples were diluted to the correct concentration prior to analysis. All systems were at or close to pH 5 after dilution. Excess gallic acid (3.5 mM) was added and the cuvette sealed air-tight for spectrophotometry

using a Perkin-Elmer Lambda-35 spectrophotometer. Samples were thermostated at 23 °C and magnetically stirred during spectrophotometry. The influence PS341 of (a change in) sample Erastin molecular weight turbidity on the absorbance was countered by using the dispersion at the same concentration but without gallic acid as reference. The gallic acid addition and vial sealing could not be done inside the spectrophotometer while the measurement was running. Therefore, the blanks were placed first and the samples with gallic acid were then prepared in quick succession. No more than two samples with gallic acid were analysed during a single experiment, so that the time between addition of gallic acid and the first measurement was never more than a few seconds. The preparation of metal pyrophosphate particles by coprecipitation of the precursor salts has been previously investigated Selleck Hydroxychloroquine (van Leeuwen et al., 2012a and van Leeuwen et al., 2012c). While this method

resulted in stable colloidal dispersions of iron pyrophosphate (FePPi), it was shown that pyrophosphate coprecipitated with a divalent metal (M2+PPi) in general formed particles that were too large to remain in suspension. Furthermore, stable dispersions of mixed systems were only prepared at a high iron content (>80%) (van Leeuwen et al., 2012c), while a lower iron content was preferable in order to reduce the reactivity of the contained iron. Preparation by coprecipitation of pure FePPi or mixed systems at a low M (Na or M2+) content resulted in clusters of small, amorphous particles, shown in Fig. 1a and observed previously (van Leeuwen et al., 2012c). The FePPi-zein preparation method yielded polydisperse particles of around 150 nm containing the insoluble salt as can be observed in Fig. 1b. An empty zein particle is shown for reference in Fig. 1c. Due to the fact that coprecipitation by slow addition is an ill-defined method of preparation, this study also used pH-dependent precipitation as a more controlled way of preparing M2+PPi particles.

6-soluble fraction proved to be an important tool to complement t

6-soluble fraction proved to be an important tool to complement the determinations of NS-pH 4.6/NT*100. Among the proteolytic agents that act during Prato cheese ripening, residual coagulant is of great importance and has a crucial role in proteolysis. The results obtained for the proteolytic indices during the 60 days of ripening for cheeses made with coagulant form T. indicae-seudaticae N31 did not differ statistically from the ones obtained for cheeses made with commercial coagulant. Furthermore, casein hydrolysis throughout the ripening of cheeses made with either

R428 mw coagulants, presented some differences as visualised by urea–PAGE and HPLC. However, making of Prato cheese with coagulant from T. indicae-seudaticae N31 was well executed under conventional production conditions resulting in a product with good technological quality. The authors would like to acknowledge the financial assistance

provided by Fundação de Amparo à Pesquisa do Estado de São Paulo, FAPESP. “
“Quinoa (Chenopodium quinoa Wild) is a pseudocereal of Andean origin and is used principally in the same manner as wheat and rice ( Hirose, Fujita, Ishii, & Ueno, 2010). There has been increasing interest in quinoa due to its superior nutritional quality compared to other grains and for not having gluten. Thus, quinoa is an alternative ingredient in the gluten-free diet and can be used by persons who suffer find more from celiac disease ( Alvarez-Jubete, Arendt, & Gallagher, 2010). For these reasons, different

studies have been carried out on the chemical composition of the quinoa seeds in the last decade and this pseudocereal has been noted as a new foodstuff in the world ( Hirose et al., 2010). The studies concerning their proteins revealed that it contains a balanced essential amino acid composition, with a high content of essential amino acids, and is thus superior to that of common cereals (Drzewiecki et al., 2003). Lipid content of quinoa is also higher (between 2 and 3 times) than in common cereals and rich in unsaturated fatty acids, which are desirable from a nutritional point of view (Alvarez-Jubete, Arendt, et al., 2010). Moreover, quinoa contains adequate levels of important micronutrients such as minerals and vitamins and significant amounts of other bioactive components, such as polyphenols, which exerts antioxidative properties (Alvarez-Jubete, Ribonucleotide reductase Wijngaard et al., 2010 and Hirose et al., 2010). Concerning the carbohydrates, they consists the major component in quinoa, and varies from 67% to 74% of the dry matter (Jancurová, Minarovicová, & Dandár, 2009). Starch is the only carbohydrate reported and its content varies from 51% to 61%, being stored in the cells of the perisperm. It can be used for specialized industrial applications due to its small granules, high viscosity and good freeze–thaw stability (Watanabe, Peng, Tang, & Mitsunaga, 2007). Moreover, studies have shown that quinoa represent a good source of dietary fiber, with a range from 1.1% to 16.

Permethrin, a synthetic pyrethroid insecticide, was selected for

Permethrin, a synthetic pyrethroid insecticide, was selected for the previous aggregate SHEDS-Multimedia model application in Zartarian et al. (2012) because it is the most commonly used pyrethroid pesticide and the first pyrethroid reviewed under FQPA. This paper extends that research, applying SHEDS-Multimedia to a cumulative seven pyrethroids case study (permethrin, cypermethrin, cyfluthrin, allethrin, resmethrin, deltamethrin, and esfenvalerate), including variability analyses for key pathways and chemicals, and selleck products model evaluation results. To select the seven pyrethroid pesticides for this case study, we used the 2001–2002

Residential Exposure Joint Venture (REJV) consumer pesticide product use survey provided to the U.S. EPA (Jacobs et al., 2003) and NHANES biomarker data (Barr et al., 2010Table 1). To our knowledge, this is the first comprehensive cumulative exposure assessment using SHEDS-Multimedia combined with publicly available datasets. The objectives of this case study were to: (1) quantify children’s pyrethroid exposures from residential and dietary routes, identifying major chemicals and A-1210477 research buy pathways; (2) provide reliable input data and methods for cumulative risk assessment; and (3) evaluate SHEDS-Multimedia

using NHANES biomarker data. The SHEDS-Multimedia technical manuals describe in detail the model algorithms, methodologies, and input and output capabilities (Glen et al., 2010 and Xue et al., 2010b). SHEDS-Multimedia is comprised of both a residential module (SHEDS-Residential version 4.0; Glen

et al., 2010, Isaacs et al., 2010a and Zartarian et al., 2008), and a dietary module (SHEDS-Dietary version 1.0; Xue et al., 2010a, Xue et al., 2010b, Xue et al., 2012 and Isaacs et al., 2010b) linked by a methodology illustrated in Fig. 1. This case study quantifies population cumulative exposures for 3–5 year olds (one of the EPA recommended age groups in U.S. EPA, 2005) from both dietary ingestion and nine residential application scenarios of seven pyrethroids. The seven pyrethroids were selected based on residential usage patterns and degradation to the common metabolites, 3-PBA and Calpain DCCA (Barr et al., 2010). For this multiple pyrethroids case study, nine residential exposure scenarios were selected based on analyses of the REJV data (Jacobs et al., 2003), including indoor crack and crevice (aerosol and liquid), indoor flying insect killer (aerosol), indoor fogger (broadcast), lawn (granular – push spreader and liquid – hand wand), pet treatment (liquid and spot-on), and vegetable garden (dust, powder). Model input values for chemical-specific and non-specific data inputs for these seven pyrethroids were mined from peer-reviewed publications, OPP’s Residential Exposure Standard Operating Procedures (U.S. EPA, 2012), recommendations by OPP’s FIFRA SAP, EPA’s Exposure Factors Handbook and Child-Specific Exposure Factors Handbook (U.S. EPA, 1997 and U.S.

Thus, the present results suggest an important exception from thi

Thus, the present results suggest an important exception from this rule. Exogenous control appears fluent and interference-resistant only once it is established and when it merely needs to be maintained across trials. In fact, what we know about the difference between exogenous buy AZD2281 and endogenous selection comes from studies using such “maintenance” conditions (i.e., pure blocks and no interruptions; e.g., Müller and Rabbitt, 1989 and Posner, 1980). The current results show that the process of intentionally selecting an exogenous mode of control seems at least as vulnerable as the process of selecting endogenous settings, at least when LTM

contains traces about competing, endogenous control settings. A remaining open question is how exactly endogenous-task interference disrupts processing on post-interruption, exogenous-task trials. Responses to sudden-onset stimuli have been proposed to reflect an unconditional, reflex-like response (e.g., Theeuwes, 2004). Therefore it would be a particularly noteworthy (and for this notion damaging) result RG7204 purchase if exogenous-task selection costs arise because the potency of the

exogenous stimulus to attract attention is reduced on post-interruption trials. Alternatively, it is also possible that the initial, exogenous pull of the exogenous stimulus remains intact and that it is only after visiting the exogenous stimulus that attention is (erroneously) brought back to inspect the central cue. We are currently investigating this important question by applying eye-tracking analyses to the exogenous/endogenous control paradigm. The LTM encoding/retrieval model of task selection that is supported by the current data has the potential of explaining traditional task-switching effects without invoking the need for passive, trial-to-trial carry-over of information. Such passive carry-over

is a hallmark of connectionist explanations for task-switch effects (Brown, Reynolds, & Braver, 2007; Gilbert and Shallice, 2002, Yeung and Monsell, 2003a and Yeung and Monsell, 2003b). Obviously, such models cannot explain selection costs that arise in the absence of any switch from the competing task. Also, these results cannot be explained by the kind of hybrid carry-over/LTM retrieval Astemizole model proposed by Waszak et al. (2003, Waszak, Hommel, & Allport, 2005). According to this account, interference does result—just as we assume––from LTM traces of earlier selection instances. However, it is the trial-to-trial carry-over of the no-longer relevant task representation (i.e., “task-set inertia”) that generates the vulnerability towards these LTM traces on switch trials. Instead, our results suggest that the a switch between competing tasks is only one instance of a broader category of events that lead to a working-memory updating state, which in turn allows interference from LTM traces to enter the system.

, 2005) Overall, birch accounted for 56% of regenerating sapling

, 2005). Overall, birch accounted for 56% of regenerating saplings in our study. The density of birch regeneration on clearfelled upland moorland on our study sites is similar to that recorded in a storm damaged lowland conifer site in Britain (Harmer and Morgan, 2009) and to clearfelled upland conifer sites in Scotland (Wallace, 1998). Despite the presence of mature individuals of ash, beech, juniper and hazel adjacent to clearfelled sites only a handful of saplings of these species were noted. selleck Overall we found that pioneer, shade-intolerant species such

as birch, rowan and willow regenerated more frequently than shade-tolerant species such as beech and holly (Brzeiziecki and Kienast, 1994). We explored the role of distance from seed source on regeneration density for distances up to 100 m from the source. The regeneration of the small-seeded and wind-dispersed alder and birch species were found to be strongly dependent on the distance from parent trees. The majority of the saplings were

found within 20 m of a parent tree, although for birch there was a long tail, limited in our study to the width of the clearfelled site. The patchy distribution which results from this clumping around seed sources is not necessarily a disadvantage for establishment of natural woodland. Rodwell and Patterson (1994) suggest that 20–50% of woodland sites should be retained as open ground to enhance structural diversity and wildlife Ceritinib value. The fluctuations in sapling density may result in a more natural woodland structure to that produced through planting. The shoulder of the regeneration curve at distances less than 10 m from the woodland edge could be attributable to an edge effect – root competition

or light and rain interception from the mature trees counteracting the increased regeneration caused by the rise in seed density as you approach the edge. The seed dispersion curve for a point source (Harper, 1977 and Nathan et al., 2001) is similarly shaped to the regeneration curves for solitary trees in having a peak in seed fall density a short distance from the parent tree. Regeneration of oak Tyrosine-protein kinase BLK and rowan was found to be significantly clumped although not significantly dependent on distance from the seed source. Rowan is primarily dispersed through ingestion by birds, particularly various thrush species (Raspe et al., 2000), while oak relies on hoarding by both birds and mammals but especially Garrulus glandarius (jay) and Apodemus sylvaticus (wood mouse) ( Forget et al., 2004), both of which occur at the study sites. The distribution of regenerating saplings will therefore be partly controlled by the behaviour of the dispersing animal. Previous work in central Europe has demonstrated that the majority of oak regeneration occurs within 100 m of a seed source and declines rapidly at greater distances ( Mirschel et al., 2011).

These results alongside with those previously obtained by other a

These results alongside with those previously obtained by other authors suggest that this group of natural compounds might be promising for future antiviral

drug design. This study was supported by CNPq/MCT/Brazil (grant number 470235/2009-8). J.W. Bertol, C.M.O. Simões, F.C. Braga, R.M. Pádua and C.R.M. Barardi are grateful to CNPq for their research fellowships, as well as C. Rigotto thanks to CAPES/MEC/Brazil for her postdoc fellowship. “
“Herpes GSK1120212 mouse Simplex Virus types 1 and 2 (HSV-1 and HSV-2) are human neurotropic viruses usually associated with infections of the skin and mucosae of different locations, most commonly the oral and genital regions. Although infections are often subclinical, HSV can cause mild to severe diseases, especially in neonates and immunocompromised individuals. Currently, there is no cure for check details the persistent infection, and prolonged therapy with the available antiherpes drugs has induced the emergence of drug-resistant virus strains.

Moreover, HSV has been described as a risk factor for HIV infection (Roizman et al., 2007). This scenario has triggered the search for new antiherpetic agents, especially those with mechanisms of action different from that of nucleoside analogs, the major class of antiviral agents used for the management of HSV infections. Besides, a treatment based on the combination of different antiviral agents can be considered a promising approach to increase antiviral selectivity while simultaneously enabling the reduction of the mafosfamide active concentrations of the drugs (Chou, 2006). Many synthetic or naturally occurring sulfated polysaccharides from different species of marine algae, bacteria, fungi, and animals have been previously shown to have antiviral activity against human and animal viruses (Ghosh et al., 2009). In the case of fungi, cell wall polysaccharides have been chemically modified to increase their solubility and enhance their biological activities (Liu et al., 2010), including their antiviral action (Zhang et al., 2004). The pharmacological effects of Agaricus brasiliensis,

a Basidiomycete fungus native to the Brazilian Atlantic forest region, have been mainly related to the presence of polysaccharides and protein–polysaccharide complexes ( Firenzuoli et al., 2008). Concerning its previous antiviral evaluation, Sorimachi et al. (2001) showed that the ethanolic fractions of A. brasiliensis mycelium and fruiting bodies inhibited HSV, poliovirus, and Western equine encephalitis virus replication. The inhibition of HSV-1 and herpes bovine virus by an aqueous extract of A. brasiliensis fruiting bodies was also demonstrated by Bruggemann et al. (2006). Additionally, both aqueous and ethanolic fruiting bodies extracts and an isolated polysaccharide from this species displayed antiviral activity against poliovirus 1, as reported by Faccin et al. (2007).

No www

No relevant change was observed from week 32 to week 40. At week 88, a reversion was observed at positions F121Y, Q137H and V151I to the wild type amino acid, maintaining T97A and showing the emergence of K42R, V72I, L234I, V258I and the major resistance mutation Y143R. T97A is a polymorphic substitution, selected by raltegravir

and is related to Y143R/C (Canducci et al., 2009). Although not directly associated to resistance, this mutation is synergic to Y143 resistant mutants, as it is capable of restoring the replication capacity of the virus (fitness), and it is expected to emerge after the fixation of 143R (Delelis et al., 2010 and Reigadas et al., 2011). The viral load documented during the presence of F121Y and T97A is over half log below historical values. However, it was also documented during previous regimens (SD-3) and therefore cannot associate these mutations to a change in replicative fitness. To determine the proportion of polymorphic

positions in the integrase gene and contextualize the amino acid substitutions of the patient’s virus, all 5102 complete integrase sequences available at LANL were downloaded. Subtype B sequences (“B global” alignment, n = 2523) were selected for amino acid composition comparison. As expected, the consensus of those sequences was identical to the Consensus B available at LANL. The RAL-NAÏVE sample did not exhibit resistance mutations to integrase inhibitors, but had mutations both in polymorphic positions, as E11D, observed in 26.9% of the B global alignment, as well as in non polymorphic positions, Selleck Tanespimycin such as Q164 K, occurring in only 0.0004% of sequences. See Supplementary data 4 for amino acid alignment of all study time points. In addition to amino acid substitutions, silent nucleotide substitutions were observed. In a total of 13 nucleotide substitutions in 143-strains, five were observed only in 121-strains. This could indicate an evolution of 143-strains from a 121-strain precursor. Analysis of the phylogenetic reconstruction shows an evolutionary pattern, with the RAL-Naïve

sequences situated closer to the main subtype B branches, with raltegravir resistant strains further away on the branch. However, the weeks 32/40 (121-strains) and week 88 sequences (143-strains) are located at two Montelukast Sodium separate terminal branches (bootstrap 89), which may suggest an independent evolution of both “121Y” and “143R” strains. Our data therefore cannot determine if a 121Y variant is the origin of the 143R variants of if it evolved directly from other precursors. In conclusion, this study documents the association of the emergence of F121Y plus L74I, T97A, Q137H and V151I mutational pattern to the virological failure of RAL-containing regimen, followed by a reversion of the F121Y substitution and appearance of Y143R after continuous exposure to the drug.

48) and test block (F[8, 120] = 3 831, p < 0 001, η2 = 0 20), as

48) and test block (F[8, 120] = 3.831, p < 0.001, η2 = 0.20), as in the AO group. We also found an interaction of session × gamble pair (F[3, 45] = 12.15, p < 0.0001, η2 = 0.45) which was, as in Experiment

1, driven by observers lower accuracy for the 40/20 pwin pair compared to actors (t[15] = 5.89, p < 0.0001) (see Fig. S4). The between-subject effect of group, i.e. Experiment 1 versus Experiment check details 3, interacted only with the main effects of session (F[1, 30] = 4.39, p < 0.05, η2 = 0.13) and of gamble pair (F[3, 90] = 3.36, p < 0.05, η2 = 0.10). Therefore, the session × gamble pair interaction in choice accuracy, seen in Experiment 1, was replicated but now within the loss domain, with this effect being driven solely by observers’ impaired accuracy for the lowest value 40/20

win pair (now 60/80 loss pair). In the explicit estimates, there was a significant main effect of session (F[1, 15] = 12.86, p < 0.005, η2 = 0.46) and of gamble (F[3, 45] = 75.85, p < 0.0001, η2 = 0.84), along with a gamble × session interaction (F[3, 45] = 8.87, p < 0.0005, η2 = 0.37). Therefore, participants’ explicit estimates of ploss for each stimulus also replicated the results of Experiment 1, supporting an over-valuing of the lowest value options (i.e. participants underestimated ploss for the 80% loss option) rather than an over-estimation of small probabilities (participants showed high estimation accuracy for options with the lower ploss) (see Fig. S5). However, in the context of this argument, it is not SCH772984 obvious why the 40% win option was not also overvalued. One possibility is that the 20% win option may be qualitatively, as well as quantitatively, of lower value since it is the only option never paired with an option of an even lower value. This might explain why we find over-valuation only for the 20% win option, but we accept that this conjecture needs to be tested directly. In Experiment 3, we also found a slight

undervaluation of 80% loss (t[15] = −2.48, p < 0.05). Observer accuracy when choosing between the 80/20 win pair also showed a trend to be lower than for actors (t[15] = 1.83, p < 0.1). The magnitude of this effect was much smaller than in the 20/40 condition and this asymmetrical effect cannot be explained solely by an error in probability assessment. However, this finding hints that both a large over-valuation for low-value options and also a smaller mis-estimation Sulfite dehydrogenase of low probabilities may be at play in Experiment 3. Experiments 1 and 3 both show an over-valuation for low-value options during observational learning, an effect evident across implicit (i.e. choice preference) and explicit indices of subjective value. This difference was evident despite the observational and operant learning tasks being matched for visual information, and for monetary incentives to learn. In contrast, Experiment 2 shows that learning is generally improved between two active learning sessions despite the time delay and the novel stimuli being learned.

It is interesting to note that the recent definition of the begin

It is interesting to note that the recent definition of the beginning of the Holocene with reference to ice cores (Walker et al., 2009) fails the criterion of

being recognizable well into the future because of the geologically ephemeral nature of ice. Some geological boundaries are characterized by distinct geochemical markers; for example, the iridium anomaly at the Cretaceous–Neogene boundary, which is thought to have find more been caused by a meteorite impact. The Anthropocene will leave numerous clear markers including synthetic organic compounds and radionuclides as well as sedimentological memories of sudden CO2 release and ocean acidification (Zalasiewicz et al., 2011b). Many older geological boundaries were defined by disjunctures in the fossil record marked by first appearances or extinctions (Sedgwick, 1852). However, the age of these has changed with improvements in radiometric age dating; for example, the beginning of the Cambrian has moved by 28 million years since 1980. There is abundant evidence that we are currently experiencing the Earth’s sixth great mass extinction event (Barnosky et al., 2011), which will be another hallmark of the Anthropocene. The changes that mark the beginning of the Anthropocene are certainly changes of sufficient magnitude to justify a geological boundary (Steffen et al., 2011), whereas the gradual

or small-scale changes in regional environments at earlier times were not. The term Palaeoanthropocene is introduced here to mark the time interval before the industrial revolution during which anthropogenic effects MEK inhibitor clinical trial on landscape and environment can be recognized but before the burning of fossil fuels produced a huge crescendo in anthropogenic effects. The beginning

of the Palaeoanthropocene is difficult to define and will remain so: it is intended as a transitional period, which is not easily fixed in time. We emphasize that we do not intend it to compete for recognition as a geological epoch: it serves to delineate the time interval in which anthropogenic environmental change began to occur but in which changes were insufficient to leave a global record for millions of years. Although it covers a time period of interest to many scientific disciplines stretching from archaeology Phosphoprotein phosphatase and anthropology to palaeobotany, palaeogeography, palaeoecology and palaeoclimate, its beginning is necessarily transitional on a global scale because it involves changes that are small in magnitude and regional in scale. The history of human interference with the environment can be represented on a logarithmic timescale ( Fig. 1), resulting in three approximately equal areas. In the Anthropocene, major changes (orange) have been imposed on natural element cycles (black bar) that were typical of pre-human times. The Palaeoanthropocene includes the Holocene (beginning 11,700 years ago) and probably much of the Pleistocene (2.