2%); this is further shown in Table 3 However, it should be furt

2%); this is further shown in Table 3. However, it should be further noted that in both cases the performance of the APCI-MS as a tool for geographical provenance determination was very good considering the high intrinsic variability due to the use of commercial samples. LY294002 Whilst the use of commercial samples does allow the inclusion of true sample variability, it does not permit strict control of process parameters that support a mechanistic explanation of the model (e.g. cultivation and irrigation practices, environmental factors, edaphological parameters, post-harvesting practices). In both internal and external validation datasets the samples originating from New Zealand

were all successfully classified, and of the total 135 samples only 4 were misclassified, resulting in an error rate of <3%. There was a similar correlation of m/z to principle components, to that observed previously ( Fig. 4b). More specifically, the first axis is proposed to be related to alkyl-esters (m/z 61, 75, 85, 89,

103, 117, 131, 145) and dehydrated alcohols (i.e. m/z 85 for 1-hexanol, m/z 57 for 1-butanol) in the form of fragments or parent ions. The second most powerful discriminating factor is shown on PC 2 and was found to associated with the green-grassy odour like volatiles such as 1-hexanal and trans-2-hexenal (m/z 101 and 99, respectively), or 1-hexanal and cis-hex-3-en-ol selleck chemical (m/z 83). Thus, complete discrimination between New Zealand and South Africa juices appear to be dependent on the ester-related flavour notes (fruity–flowery), whilst the Chilean samples appear to be discriminated by moderate ester concentration and low amounts of green-grassy flavour type volatiles. Finally, it should be noted that the variability of the New Zealand and South Africa labelled juices based on the green-grassy flavour criterion was quite high which would indicate differences in the ripening level of the sampled apples. In conclusion, a PLS-DA chemometric approach was demonstrated to be a viable tool for the interpretation of raw APCI-MS data. The models generated were robust enough to reliably discriminate (100% correct

classification with external validation set) Tolmetin apple juices prepared from Braeburn, Golden Delicious, Granny Smith, Jazz and Pink Lady varieties, furthermore developments on the model allowed the reliable (94.2% correct classification with external validation set) discrimination of the geographical provenance of monovarietal clarified apples from Chile, New Zealand and South Africa. “
“Coffee is one of the most valuable basic products, constituting the second major commodity just after oil (ICO, 2012 and Nabais et al., 2008). According to the International Coffee Organization – ICO (2012), the total coffee production in crop year 2011/2012 was about 131.3 million bags (each bag weighing 60 kg), with approximately 33.1% produced in Brazil.

The fact that different concentrations of Cu(II) were found using

The fact that different concentrations of Cu(II) were found using both methods in the samples analyzed is not surprising since the coffee samples were produced in areas distant from one another. As a consequence, the mineral soil composition, as well as the fertilizers used, could influence the

results. Similar results were found by other authors ( Oleszczuk et al., 2007 and Onianwa et al., 1999) for the content of copper in solid coffee samples from different areas around the world, however, no results could be found in the literature concerning the content of copper in samples of instant coffee. The standard addition method and the recovery experiments were carried out using the electroanalytical Ipatasertib molecular weight sensor. The recovery values ranged from 90.0% to 110.0% for sample A, 112.0% to

120.0% for sample B, and 118.0% to 120.0% for sample C. According to the literature ( Ribani, Bottoli, Collins, Jardim, & Melo, 2004), the acceptable range of recovery values is generally between 70% and 120% and, depending on the analytic complexity of the sample, may be extended to 50%–120%. The results obtained indicate that the accuracy of the proposed method using the CPE-CTS is not affected by the matrix complexity. Taking into consideration these results we can conclude that the sensor is suitable for Cu(II) determination in instant coffee samples. A novel Small molecule library research buy carbon paste electrode containing chitosan crosslinked with the chelating Tobramycin agent 8-hydroxyquinoline-5-sulphonic acid and glutaraldehyde was developed for determination of Cu(II). The analysis was carried out employing a pre-concentration step at controlled-potential and detection by square wave voltammetry. The results showed that the response of the proposed modified

electrode was more than six times better than that of the bare carbon paste electrode. The optimisation of experimental conditions showed that the pH of the solution strongly affects the voltammetric response and pH 6.0 was the optimal value found. The validation parameters determined using the optimal experimental conditions showed a linear range for quantitative determination of Cu(II) from 5.0 × 10−7 to 1.4 × 10−5 mol L−1 and good detection limit with a pre-concentration time of 180 s. The analytical application of the method employing standard addition showed a recovery that was only slightly dependent on the matrix complexity, verifying the viability of the proposed sensor for Cu(II) determination. The use of the spray drying technique in the preparation of CPE-CTS highlighted the great potential of this technique as an alternative for developing new compounds for further use in the construction of modified carbon paste electrodes and for application in various electroanalytical processes. The authors are grateful to CNPq-Brazil for financial support. L.V. wishes to thank Prof. Valfredo T. Fávere for providing the microspheres of chitosan and 8-hydroxyquinoline-5-sulphonic acid.

It did not evaluate in any detail the release mechanisms The mai

It did not evaluate in any detail the release mechanisms. The main conclusions from that work are as follows (Nowack et al., 2012): The release of CNTs from products or articles containing CNT-composites may occur over a long time scale and thus this material will probably alter at a slow rate. It was considered that CNTs can be released upon photochemical Tanespimycin nmr degradation of CNT-containing composites. These released CNTs can be transported

to wastewater treatment plants (WWTP) or be directly deposited into environmental compartments where they would undergo transformation by photochemistry, oxidation, adsorption of natural organic matter and other organic BMS-754807 in vivo colloids, biotransformation, and continued abrasive forces. These transformation processes are thought to change CNT aggregation, dispersibility, and interaction with biota in the environmental compartment. The disposal methods, i.e., incineration, WWTPs, and landfill disposal apply to both the CNT composite as well as released CNTs. The incineration of CNT composites subjects them to high temperatures that might result in the airborne release of CNTs if the CNTs survive at

low temperature for a short time. Theoretically CNTs should be burned and mineralized during incineration, as the temperature (around 1000 °C) is higher than the ignition temperature of CNTs (normally below 600 °C) (Sobek and Bucheli, 2009) and the waste is incinerated in the presence of oxygen. However, poorly controlled incineration might result in lower temperatures that would not destroy the CNTs. Disposal of CNT composites in landfills could lead to degradation

or transformation of the polymers, resulting in possible release of CNTs, depending on the presence and efficiency of landfill liners. The main conclusion from this generic release scenario is that after release of CNTs to the environment a multitude of reactions can affect the form of the CNTs and result either in complete destruction or change of properties. The potential release scenarios that are formulated in this review begin with formation of the solid product (master batch) and move Monoiodotyrosine through its life-cycle as a product and article, ending with the article’s reuse or disposal. Exposure scenarios during formation of the master batch as presented by (Fleury et al., in press) are therefore not part of our analysis. The synthesis of CNTs and the making of the master batch (extrusion) are not included in the evaluation. The pelletizing of the master batch is the first process considered. The life-cycle may roughly be broken into three stages: – Manufacturing of CNT/matrix, i.e. the introduction of CNTs into the matrix, and the ultimate product, e.g. a master batch or paint, or article made from/with the CNT/matrix.

During the setting up of the experiment in 1994, a control transp

During the setting up of the experiment in 1994, a control transplantation was made at the site of lichen collection, Skånberget, Ramsjö, in the province of Hälsingland, in south boreal Sweden, ca 300 km north of the experimental area. On the north and south sides of 20 trees material of two types was mounted, such that had been frozen for more than one month, i.e. resembling the treatment in the experiment, and also fresh material, in total amounting to 80 transplants. The survival and vitality of these transplants were re-assessed in August 2008. Generalized linear mixed models (GLMMs) with logit link

functions and Laplace approximation (Bolker et al., 2009) were first applied to test the effect of tree retention, aspect, and transplantation time for transplant survival and vitality

in 2008, Gefitinib and MAPK Inhibitor Library second to assess if there was a significant difference in the variables that described survival and vitality in both survey years. The effect of tree retention was tested in two different models, one testing if transplant survival and vitality differed between trees in the forest and clearcut, and the second one testing if there was a difference in transplant survival and vitality between grouped and scattered retention trees. The following binary response variables (1/0) were used: survival was defined as the transplanted thallus being present (1) or absent (0), and vitality as ⩾50% of the thallus being vital (1) or <50% of the thallus being vital (0). The global start model for the data of 2008 included forest stand and tree as random factors, and aspect (north or south), forest type (forest or clearcut) or clearcut type (grouped or scattered retention trees), tree diameter (measured in 1996), and transplantation time (spring 1994 or autumn 1994) as fixed effect variables. In the second model, survey year (1996 or 2008) was used as an additional fixed effect variable.

Tree diameter was not used in this model since we were not interested if the effect of tree diameter had changed between both survey years. For better comparison between the two survey years we also tested a third model, including only the data of 1996, but running the model in the same way as described for the data of 2008. This was done since the data analysis Non-specific serine/threonine protein kinase in Hazell and Gustafsson (1999) used a different statistical approach. Biological meaningful interaction terms were added and all fixed explanatory variables in the interaction terms were centered and scaled (in the case of tree diameter) in order to achieve biologically interpretable estimates (Schielzeth, 2010). Akaike’s Information Criterion (AIC, or AICc for small sample sizes) and Akaike weights were used to assess the relative strength of support for all biologically considerable models, given the chosen explanatory variables (Akaike, 1974 and Burnham and Anderson, 2002).

, 2013) and research on temperate trees indicates that high genet

, 2013) and research on temperate trees indicates that high genetic variation helps support ecosystem functions (Whitham et al., 2006). When out-crossing indigenous trees exist only at very low densities in farmland, however, as is often the case when they are remnants from Palbociclib order natural forest otherwise cleared for crop planting (Lengkeek et al., 2005), they are vulnerable to the absence of neighbours in the landscape to support pollination, reducing the opportunities for reproduction and potentially leading to lower seed set and inbreeding depression (Lowe et al., 2005). This is a particular

concern for trees that provide fruit for human consumption, as no cross-pollination/the absence of fruit set may mean there is no reason for farmers to retain these trees in the agricultural landscape (Dawson et al., 2009). In the worst case scenario, rare, isolated trees in farm landscapes may be the ‘living dead’ (sensu Janzen, 1986; i.e., unable to pollinate and set seed) and will only survive for the current generation. Some have argued that further promoting tree domestication has negative impacts for the diversity of agricultural landscapes at both inter- and intra-specific levels, and this is most clearly seen if it leads to clonal tree monocultures (see Section 4.3). On the other hand, without the improvements in tree yield and quality associated with domestication, farmers may choose

not to plant trees at all on their land, but to cultivate other plants that are (otherwise) more productive (Sunderland, 2011). At an intra-specific level, domestication processes always cause shifts and/or losses in underlying genetic selleck kinase inhibitor diversity in the manipulated populations (Dawson et al., 2009), but the extent and nature of these changes depends on the domestication method adopted, with some approaches more favourable for maintaining diversity (Cornelius et al., 2006). The participatory domestication approach (Appendix B, Fluorometholone Acetate Section 3.2), which is based on bringing selected indigenous trees from local wild stands into farms, appears to provide a good balance between farm-level productivity gains and the landscape-level conservation of genetic

resources (Leakey, 2010). Genetic-model analysis of a participatory domestication project with peach palm in Peru, for example, showed that the risk of genetic erosion in a regional context was low (Cornelius et al., 2006). The wide use of clonal propagation methods during participatory domestication could, however, cause longer-term challenges for intra-specific diversity, especially if substantial inter-village germplasm exchange occurs (expansion of a few clones). Tree commodity crops represent something of an exception to the sparse information available on the value of other tree products (as exemplified in Sections 2 and 3), as export data are compiled widely by national governments and are further assembled by FAO’s Statistics Division (FAOSTAT, 2013).

Full profiles were obtained from the five individuals with swabs

Full profiles were obtained from the five individuals with swabs ranging from 14 days to 395 days old demonstrating

the effectiveness of the system to process older swabs. Average peak heights ranged from 400 to 4600 RFUs, and average heterozygote peak height ratios ranged from 85.1 to 88.8%. All profiles were concordant with the reference profiles demonstrating the reproducibility of the system with aged buccal swabs. Analysis of 2 ng positive control DNA 007 (n = 4) run on four different instruments showed similar average peak heights (range 1629–4324 RFU) and average heterozygote peak height ratios (range 85.6–88.2%). selleck chemicals Differences in average intracolor balance were minimal and ranged Selleckchem Vemurafenib from 5 to 14% (data not shown). Twenty-one buccal swabs that had previously been run on the RapidHIT and re-extracted on the bench had DNA yields ranging from 2.3 ng to 1.6 μg. Profiles obtained after amplification of the re-extracted DNA with the GlobalFiler Express kit yielded concordant profiles with their GlobalFiler Express profile generated on the RapidHIT as well as their profile in the reference database (data not shown). These developmental validation studies have demonstrated that the GlobalFiler Express assay run on the RapidHIT System is a reliable system for generating profiles after forensic review

from references samples. While the quality of the STR profile can be affected by the thermal cycling parameters, the results from boundary studies around the optimized conditions illustrate the robustness of the protocol and system to generate STR profiles within ±2 °C degree changes in temperature and up to 2-fold changes in extraction conditions studied. These optimized PCR conditions maintained the same primate specificity of the GlobalFiler

Express assay as previously validated eltoprazine by the kit manufacturer, ThermoFisher Scientific [12]. PCR inhibitors can impact the generation of a complete STR profile [19], [20] and [21]. DNA extraction and purification with mock inhibitors showed that the system is effective at removing inhibitors and can process buccal swabs and blood samples. PCR and extraction conditions were optimized on the RapidHIT System to generate full profiles from buccal swabs. In the sensitivity studies, full profiles were obtained with 6260 cells (37.5 ng) and 2.5 μL of blood (25 ng) applied to swabs indicating the sensitivity of detection is clearly within the limits needed to recover a profile from oral buccal swabs. Likewise, a single touch of swab to cheek shows there is a sufficient amount of cells and DNA (e.g. ∼25 ng) being recovered to yield full DNA profiles. Partial profiles were obtained with 3125 cells (∼19 ng) and 1 μL blood equivalent of ∼10 ng of DNA. Modification of the protocol, such as increasing the number of PCR cycles, could extend the sensitivity of the system to handle samples with lower DNA input.

1% crystal violet, and the viral plaques were counted For the 96

1% crystal violet, and the viral plaques were counted. For the 96-h assays and Androgen Receptor Antagonist nmr for experiments using recombinant VACV-WR expressing mutated F13L, 1% 2-methylcellulose was added to the medium at 0 h. The percentage of inhibition of plaque formation was calculated as follows: 100 − [(mean number of plaques in test × 100)/(mean number of plaques in control)]. The EC50 values (effective concentration of drug required to inhibit 50% of virus replication) were derived from the plots. In some experiments, cytopathic effect reduction assays were conducted to measure the effective concentration

of compound that inhibited 50% of the virus induced CPE. BSC-40 monolayers were seeded in 96-well plates at 1 × 104 cells per well in 180 μl of growth media. ST-246 was added directly to the assay plates at 24 concentrations (0.001–5 μM) using the HP D300 digital titration instrument (Hewlett Packard, Corvallis, OR). Cell monolayers were infected with wild-type vaccinia virus or the vaccinia virus recombinants containing the D217N amino acid substitution using an amount of virus that would cause 95% CPE at 3 days post-infection. The assay was terminated at 3 days post-infection by fixing the cells in 5% glutaraldehyde solution and the amount of CPE was visualized by staining the monolayers with 0.1% crystal

violet. Virus-induced CPE were quantified by measuring absorbance at 570 nm. www.selleckchem.com/products/pci-32765.html The EC50 values were calculated by fitting the data to a four-parameter logistic model Glycogen branching enzyme to generate dose–response curve using XLfit 4.1 (IBDS, Emeryville, CA). Monolayers of BSC-40 cells (1 × 106 cells/well) were infected with 200 PFUs of the recombinant viruses CTGV-βGal or VACV-WR-βGal

and cells were either treated with 0.01, 0.02 or 0.05 μM ST-246 or with 0.05% DMSO (control). At 48 h post-infection, the monolayers were fixed with 4% paraformaldehyde, washed twice with PBS 1× and incubated 18 h at room temperature with a solution containing 0.4 mg/ml X-Gal, 4 mM potassium ferrocyanide, 4 mM potassium ferricyanide, and 2 mM MgCl2 (Sanes et al., 1986). The sites of enzyme activity were detected through the visualization of blue viral plaques. For measurement of β-galactosidase activity, the monolayers were infected and treated with ST-246 as described above, and after 48 h the cells were processed as described (Chakrabarti et al., 1985). Cellular extracts were mixed vigorously with chloroform/SDS, and incubated with 4 mg/ml ONPG [O-nitrophenyl-B-d-galactopyranoside] until a light yellow color was developed. The samples were quantified at A420nm. BSC-40 cells grown in 6-well plates (1 × 106 cells/well) were infected with 50 PFU of CTGV or VACV-WR and either treated with 0.05% DMSO (control) or with different concentrations of ST-246. The plates were incubated tilted at a 5° angle for 3–4 days at 34.6 °C and then stained with 0.1% crystal violet. Comet tail formation in vehicle-treated group and ST-246 treated cells was compared by visual inspection.

Based on emergence and loss patterns, the floods had a net effect

Based on emergence and loss patterns, the floods had a net effect of redistributing sediments from areas Venetoclax in vitro exposed to river currents at all stages to more protected areas

which only experience significant flow during high water. Between 1975 and 1989 both growth and loss occurred. Rapid emergence occurred between 1975 and 1979, faster than any other period in the historical record. Loss occurred again in 1979–1989, and almost all areas that had emerged in 1975–1979 disappeared. In 1989, land area in LP6 was only 0.01 km2 greater than it had been in 1975. This dynamism appears to be real rather than a result of differences in water levels between datasets, because water levels in 1975 and 1979 were only 3 cm different, and in 1989 the stage is only 16 cm higher than in the 1979 photograph. Overall, land area in 1989 was 45% smaller than it had been in 1940 (Table 3). The largest losses took place along the Minnesota and Wisconsin shorelines and the Island 81 complex, including the complete loss of its

middle portion. The only area in LP6 where net growth occurred was in the Mobile Islands. Between 1895 and 1989, mid-channel island and bank-attached land exhibited parallel patterns of growth and loss (i.e., if islands lost area during a period, MG-132 datasheet bank-attached land lost a similar percent of area). The only exception to this pattern was 1962–1975, when bank-attached land lost 24% of its area relative to 1962, but islands increased in area by 17% relative to 1962. 1962–1975 corresponds with the period in which Lower Mobile Island emerged. Land emergence prevailed from 1989 to 2010

(Fig. 4), with more rapid growth in mid-channel islands than bank-attached land. Since 1989, the Island 81 complex substantially infilled, and new islands are developing downstream in areas that were emergent and contiguous with Island 81 in the 1895 and 1931 surveys. Overall, by 2010, the area of the Island 81 complex increased 77% relative to its 1989 land area (Table Enzalutamide 3). The Mobile Islands increased 146% during the period, with lower Mobile Island accounting for most of the growth. A new island (“Gull Island”, Fig. 5) emerged between the Mobile Islands and the Island 81 complex and rapidly grew to ∼2.8 times larger than the Mobile Islands. This new island emerged following the 1993 flood, first appearing as a sand bar with a large tree embedded. The island enlarged significantly following the 1997 flood (Jefferson, personal observation). Gull Island developed in an area that was largely submerged in 1895 but had emerged by 1931. By 2010, its area was nearly the same size as it had been in 1931. Gull Island also lies on top of and between submerged wing dikes, which were built in a secondary channel largely obstructed by a closing dike. Mid-channel islands comprised 62% of LP6 land area in 1895, decreased to 50% by 1962, but subsequently increased to 67% of LP6 land area by 2010.

Combined with the long-term trend toward increasing aridity, exti

Combined with the long-term trend toward increasing aridity, extinctions may have resulted from a complex feedback loop where the loss of large herbivores increased fuel loads and generated more intense fires that were increasingly ignited by humans (Barnosky et al., 2004 and Wroe et al., 2006). Edwards and MacDonald (1991) identified increases in charcoal abundance and shifts in pollen assemblages, but arguments still remain over the chronological resolution and whether or not these are tied to natural or anthropogenic burning

(Bowman, 1998). Evidence for anthropogenic burning in the Americas and Eurasia is more ephemeral, although Robinson et al. (2005) reported evidence for increased charcoal and human burning in eastern North America in the terminal Pleistocene.

Similar to some earlier syntheses (e.g., Nogués-Bravo et al., 2008), Fillios et al. (2010), argue that humans provided the coup de grâce in megafaunal extinctions Raf inhibitor in Australia, with environmental factors acting as the primary driver. In a recent study, Lorenzen et al. (2011) synthesized archeological, genetic, and climatic data to study the demographic histories of six megafauna species, the wooly rhinoceros, wooly mammoth, wild horse, reindeer, bison, and musk ox. They found that climatic fluctuation was the major driver of population change over the last 50,000 years, but not the sole mechanism. Climate change alone can explain the extinction of the Eurasian musk ox and the wooly rhinoceros, buy PD0332991 for example, but the extinction of the Eurasian steppe bison and wild horse was the result of both climatic and anthropogenic influences. Lorenzen et al.’s (2011) findings demonstrate the need for a species by species approach to understanding megafaunal extinctions. The most powerful argument supporting a mix of humans and climate for late Quaternary megafauna extinctions may be the simplest. Given current best age estimates for the arrival of AMH in Australia, Eurasia, and the Americas, a wave of extinctions appears to have occurred shortly

after human colonization of all three continents. In some cases, climate probably contributed significantly to these extinctions, Thiamet G in other cases, the connection is not as obvious. Climate and vegetation changes at the Pleistocene–Holocene transition, for example, likely stressed megafauna in North America and South America (Barnosky et al., 2004 and Metcalfe et al., 2010). The early extinction pulse in Eurasia (see Table 3) generally coincides with the arrival of AMH and the later pulse may have resulted from human demographic expansion and the invention of new tool technologies (Barnosky et al., 2004:71). This latter pulse also coincides with warming and vegetation changes at the Pleistocene–Holocene transition. Extinctions in Australia appear to occur shortly after human colonization and are not clearly linked to any climate events (Roberts et al.

A similar strategy was used recently to show that Nespas macro nc

A similar strategy was used recently to show that Nespas macro ncRNA in the Gnas cluster silences Nesp, but the impact of the ncRNA truncation on the other promoters in the cluster has not yet been reported [ 7••]. Genes showing ML imprinted expression may or may not be overlapped by the regulating macro ncRNA. However, all genes showing EXEL imprinted expression are not overlapped and lie further away

from the ncRNA, making them MK8776 a better model to understand long-range cis-silencing by ncRNAs. EXEL imprinted expression is restricted to certain cell types in extra-embryonic tissues, meaning studies of EXEL gene regulation can be compromised when using an intact organ like placenta that contains non-EXEL embryonic cell types as well as maternal endothelial and blood tissue. We have recently shown that visceral endoderm, an EXEL cell type, can be efficiently isolated from

visceral yolk sac providing a homogenous cell population to study EXEL gene regulation in vivo [ 11••]. This review examines recent findings that provide information on how imprinted macro ncRNAs may cause long-range cis-silencing of EXEL genes, focusing on silencing by Airn and Kcnq1ot1 in the Igf2r and Kcnq1 clusters ( Figure 1). The Kcnq1ot1 macro ncRNA is transcribed from the unmethylated paternal ICE located in intron 10 of Kcnq1 and silences four ML genes and six EXEL genes on the paternal

allele ( Figure 1a). Using quantitative polymerase chain reaction (qPCR) assays, it was recently reported that Kcnq1ot1 is 471 kb click here long in all examined tissues, and therefore overlaps all downstream genes, including EXEL genes [ 26]. However, this finding conflicts with previous reports using qPCR and RNase protection assays that mapped Kcnq1ot1 to be 91 kb or 121 kb [ 22 and 27]. In addition, our own RNA sequencing data and the distribution of reported ESTs are consistent with the earlier either studies, mapping Kcnq1ot1 to be between 83 and 121 kb, meaning that it would only overlap Kcnq1 introns 10–11 ( Figure 1a) [ 28]. The Kcnq1ot1 RNA is reported to have different behaviour in embryonic versus extra-embryonic tissues. The Kcnq1ot1 RNA fluorescence in situ hybridization (FISH) signal is larger in placenta than in embryo, correlating with the greater number of genes silenced in the placenta [ 22]. Kcnq1ot1 also shows a greater association with chromatin in placenta than embryo, implying an association between the ncRNA product and the chromosome in placenta [ 27]. In Trophoblast Stem (TS) cells, the precursor of EXEL cell types in the placenta, Kcnq1ot1 colocalises with a contracted chromosome compartment containing the entire Kcnq1 imprinted cluster and the repressive chromatin modifications H3K9me3, H2A119u1 and H3K27me3 [ 29••].