text:
- Research article
- Open Access
Genetic dissection of maize phenology using an intraspecific introgression library
© Salvi et al; licensee BioMed Central Ltd. 2011
- Received: 4 June 2010
- Accepted: 6 January 2011
- Published: 6 January 2011
Collections of nearly isogenic lines where each line carries a delimited portion of a donor source genome into a common recipient genetic background are known as introgression libraries and have already shown to be instrumental for the dissection of quantitative traits. By means of marker-assisted backcrossing, we have produced an introgression library using the extremely early-flowering maize (Zea mays L.) variety Gaspé Flint and the elite line B73 as donor and recipient genotypes, respectively, and utilized this collection to investigate the genetic basis of flowering time and related traits of adaptive and agronomic importance in maize.
The collection includes 75 lines with an average Gaspé Flint introgression length of 43.1 cM. The collection was evaluated for flowering time, internode length, number of ears, number of nodes (phytomeres), number of nodes above the ear, number and proportion of nodes below the ear and plant height. Five QTLs for flowering time were mapped, all corresponding to major QTLs for number of nodes. Three additional QTLs for number of nodes were mapped. Besides flowering time, the QTLs for number of nodes drove phenotypic variation for plant height and number of nodes below and above the top ear, but not for internode length. A number of apparently Mendelian-inherited phenotypes were also observed.
While the inheritance of flowering time was dominated by the well-known QTL Vgt1, a number of other important flowering time QTLs were identified and, thanks to the type of plant material here utilized, immediately isogenized and made available for fine mapping. At each flowering time QTL, early flowering correlated with fewer vegetative phytomeres, indicating the latter as a key developmental strategy to adapt the maize crop from the original tropical environment to the northern border of the temperate zone (southern Canada), where Gaspé Flint was originally cultivated. Because of the trait differences between the two parental genotypes, this collection will serve as a permanent source of nearly isogenic materials for multiple studies of QTL analysis and cloning.
- Quantitative Trait Locus
- Plant Height
- Flowering Time
- Flint
- Quantitative Trait Locus Analysis
The production and the phenotypic analysis of pairs of nearly isogenic lines (NILs) differing only for the allele constitution at given chromosome regions provides the opportunity to test for the presence at such regions of genetic factors involved in the inheritance of a quantitative trait [1, 2]. In comparison with Quantitative Trait Locus (QTL) analysis carried out based on classical biparental mapping populations such as F2, recombinant inbred lines (RILs), etc., this should in principle enhance the statistical power of QTL detection by eliminating the blurring effect of multiple, and possibly interacting, segregating QTLs. A collection of NILs, each one differing from a reference recipient genotype for a known limited chromosome region, and altogether representing most of a donor genome, is known as introgression library (IL) [3, 4]. In an IL, the donor genome is usually provided by an interfertile accession (usually a landrace or a wild relative), while a breeding elite strain is used as the recipient genetic stock. The process of IL production invariably involves some backcrossing scheme with the assistance of marker surveys during or after the backcross. ILs have been produced for a number of model and crop plant species (Reviewed in [5]; see also [6, 7]), and even for model animal species such as mouse [8] and Caenorhabditis [9]. A pair of fully reciprocal IL populations were produced in Arabidopsis [10], with the two accessions used once as donor and once as recipient. One IL was described in maize involving two inbred lines, Tx303 and B73, as donor and recipient genotypes, respectively [11].
An IL enables moving and testing alleles from wild or landraces accessions into the elite gene pool of a crop, thus making possible their exploitation in plant breeding [4]. Accordingly, introgression lines belonging to partial or complete IL were proven to have breeding potential in cotton [12], maize [13], rice [14] and tomato [15]. Additionally, IL lines played a major role in enabling the positional cloning of major QTLs (eg. [16, 17]), by providing the starting plant material where the genetic effect of the target QTL could be followed as any other Mendelian locus.
Here we describe the general features and the initial phenotyping of a maize intraspecific IL obtained using Gaspé Flint as the donor genotype and the elite line B73 as the recipient genotype. Gaspé Flint is a variety belonging to the Northern Flint maize race group [18], which was cultivated by American Native populations in southeastern Canada [19]. It is virtually the earliest known maize genotype and such earliness is the basis of its adaptation to the very short summer growing season of Canada. One of the genetic determinants of Gaspé Flint extreme earliness, the Vegetative to generative transition1 (Vgt1) QTL [20, 21] has already been identified by positional cloning and shown to correspond to a non-coding, enhancer-like regulatory element of the AP-2 class transcription factor ZmRap2.7 [22]. The herein described B73 × Gaspé Flint IL lays the foundations for the genetic and molecular characterization of additional genetic determinants of flowering time and other traits of agronomic and adaptive importance in maize.
Features and coverage of the introgression library
Main features of the B73 × Gaspé Flint introgression library
IL lines characteristics
% of maize genome a
IL lines (No.)
Mean length of introgression in frame (cM)
Range of introgression length 'in frame' (cM)b
4.5 - 104.0
0.3 - 5.8
IL lines with completely homozygous introgression (No.)
IL lines with partially homozygous introgression (No.)
IL lines with completely heterozygous introgression (No.)
IL lines with verified additional introgressions (No.)
Mean length of verified additional introgressions (cM)
Mean length of total introgression per line (cM)
Chromosome regions with four or more adjacent monomorphic SSR markers between B73 and Gaspé Flint
Chromosome bin
Markers included (No.) a
Marker interval
Total (% maize genome)
Chromosome coverage of the B73 × Gaspé Flint introgression library
Coverage of
Maize genome
Whole IL
With the only aim to support and verify the QTL analysis results based on the IL population, we additionally characterized two small populations, a BC1 (88 plants) and an F2 (65 plants) both derived from B73 × Gaspé Flint crosses (see Methods).
Phenotypic analysis
Summary of phenotypic values for B73, F1 B73 × Gaspé Flint and Gaspé Flint, and trait heritability (h2)
Acronym (unit)
Gaspé Flint
Days from planting to pollen shed
DPS (days)
Number of ears
EARN (count)
Growing degree unit
GDU (unit)
Internode length
INDL (cm)
Number of nodes
ND (count)
Number of nodes above the top ear
NDAE (count)
Number of nodes below the top ear
NDBE (count)
Plant height
PH (cm)
Proportion of nodes below the top ear
PNDBE (rate)
The majority of the IL lines had DPS, GDU, ND, NDBE and PH values close to B73 and only mildly skewed distributions toward the Gaspé Flint values were observed, accordingly with the recovery of most of the B73 genome (and therefore QTL alleles) in all lines (Additional file 1). ND, NDAE and NDBE values were non-normally distributed (P < 0.01). EARN and ND resulted non-normally distributed in the BC1, similarly to EARN, ND and ND-related traits in the F2.
The BC1 population showed a DPS frequency distribution shifted to lower values when compared with the F2 population (Additional file 1). The shift was likely observed because the BC1 population was grown later in the summer, in conditions of higher mean temperatures (not shown). As a confirmation, the shift disappeared when GDU were considered instead of DPS (Additional file 1). The ANOVA (or Kruskal-Wallis test), evidenced significant variation among IL lines (P < 0.001; not shown) for all traits. Broad sense heritability values ranged between 0.57 for PNDBE to 0.98 for ND (Table 4). Generally, plant (for F2 and BC1) or line (for IL) values were within parental values and little or no transgressivity was observed for the three populations with the exceptions of PH and INDL (Additional file 1). For PH and INDL, transgression was observed in the F2 and BC1 populations, with values higher than the high parent. This type of transgression (beyond the high-value parent) for plant height and related phenotypes is not unexpected given the inherent heterozygosity of F2 and BC1 populations that typically positively influences hybrid vigor. The transgressivity observed in the IL population is specifically treated in the QTL section.
Correlation among traits
Genotypic (above diagonal) and phenotypic (below diagonal) correlations between traits based on the B73 × Gaspé Flint introgression library
QTLs for flowering time
Features of the QTLs identified in the B73 × Gaspé Flint introgression library
QTL a
cM b
Marker interval c
Effect d
25.8 - 69.6
108.7 - 134.0
69.2 - 144.5
59.2 - 82.4
25.8 - 69.6
108.7 - 134.0
69.2 - 144.5
70.7 - 91.6
59.2 - 82.4
59.2 - 82.4
ns (0.10)
25.8 - 69.6
108.7 - 134.0
36.1 - 49.2
69.2 - 144.5
58.8 - 82.6
70.7 - 91.6
59.2 - 82.4
43.8 - 97.7
58.8 - 82.6
69.2 - 144.5
70.7 - 91.6
25.8 - 69.6
108.7 - 134.0
69.2 - 144.5
70.7 - 91.6
59.2 - 82.4
43.8 - 97.7
108.7 - 134.0
69.2 - 144.5
70.7 - 91.6
43.8 - 97.7
The strongest QTL was identified at bin 8.04-8.05 in the IL, F2 and BC1 populations, accordingly with the known position of Vgt1 and Vgt2 [20]. The additive effect (ai, with i = IL or F2) attributed to Vgt1-Vgt2 complex locus in this study was estimated as aIL = -2.0 and aF2 = -1.5 nodes (sign indicates direction of effect induced by a Gaspé Flint allele). The Gaspé allele showed partial dominance. The Vgt1-Vgt2 region showed additional effects on DPS, NDBE, NDAE, and PH in the IL, on NDBE, DPS, and PH in the F2, and on DPS and PH in the BC1.
The second strongest effect QTL was qVgt-3.05/7 (aIL = -1.1). Additional significant effects were recorded for DPS, NDBE, NDAE, and PH. On the same chromosome, we identified qVgt-3.03 (aIL = -0.7). The BC1 QTL analysis confirmed the presence of flowering time QTL(s) on chr. 3, although the small population size likely precluded the clear separation of LOD peaks.
Two QTLs, qVgt-1.02/3 and qVgt-1.05/6, were identified on chr. 1. Such QTLs showed similar genetic effects for ND (aIL = ca. -0.8 and -0.9 nodes, respectively) and the same effect for DPS (aIL = ca. -1.6 days). The F2 LOD profiles indicated the presence of small effect QTLs for DPS at bin 1.02/3 and for PH at bin 1.05/6. The QTL analysis on BC1 identified a DPS QTL at an intermediate position between the two previous locations.
One QTL was identified on chr. 4 (qVgt-4.04/5) with aIL = -0.4 nodes. An ND QTL peak (although at sub-significance level, LOD peak = 2.6, threshold at LOD = 2.8) was identified at the same position in the BC1 population.
One QTL, qVgt-9.03/4, with aIL = -0.7 nodes was identified on chr. 9. The IL lines sharing similar chr. 9 introgressions showed a consistent although not significant effect on DPS as well. The presence of a QTL was confirmed by significant ND and NDBE LOD peaks and a consistent DPS LOD profile in the F2 population while the BC1 map did not properly cover this chromosome region.
On chr. 10, the qVgt-10.04/5 QTL was detected with a rather conspicuous additive genetic effect (aIL = -1.0 nodes) and with correlated effects on NDBE and PH and just below significance on DPS (not shown). Confirmation of map location was obtained with the F2 QTL analysis for ND, DPS, NDBE, NDAE and PH. No QTL was identified in this region in the BC1 population probably because of the reduced effect of the QTL in the BC1, since the B73 alleles showed partial dominance (at least for DPS, NDBE and NDAE). Alternatively, this QTL could be particularly sensitive to environmental cues, since the BC1 population was grown in a different year as compared to the IL and the F2, and with a late planting date. Interestingly, a QTL for photoperiod sensitivity was mapped right at bin 10.04 in several other studies [24–26].
The results of the QTL analysis for GDU were virtually equivalent to those for DPS (Table 6) and will not be discussed further.
Other IL lines showing remarkable flowering phenotypes
A limited number of IL lines, namely ILL4, ILL12, ILL44, ILL51 and ILL63 (Figure 1B), showed flowering time-related phenotypes and yet their introgressed regions were not considered in the QTL summary because of lack of further experimental evidence from other lines or lack of coincidence with the F2 and the BC1 results. It should be noted that ILL4, ILL12 and ILL44, while not showing any ND change when compared to B73, flowered significantly later than the latter. Such subtle effect likely went undetected in the BC1 and F2 populations.
QTLs for other traits
In keeping with the high phenotypic and genotypic correlation values, lines showing an effect on ND almost invariably influenced NDBE, with the only exception being the two minor QTLs qVgt-3.03 and qVgt-4.04/5. A similar trend was observed for NDAE, although in this case only three Vgt QTLs reached significance. The F2 QTL analysis confirmed the effects of Vgt QTLs on NDBE and NDBE, albeit at fewer QTLs, in accordance with the lower detection power of the F2 experiment.
The Gaspé Flint introgressions corresponding to qVgt-1.05/6, qVgt-3.05/7, Vgt1-Vgt2 and qVgt-10.04/5 significantly affected PH within the IL, with the Gaspé allele reducing PH. Additionally, PH mean values were similarly reduced, albeit not significantly, by the Gaspé allele at the other qVgts. The analyses of the F2 and BC1 identified two additional PH QTLs, at bins 8.06/8 and 10.01/4, respectively, which did not correspond to any qVgts. For the latter QTL, Gaspé Flint provided the allele with the positive effect.
One line (ILL71, bin 9.03/4) showed a significant effect on INDL, with the Gaspé Flint allele increasing the trait value (aIL = 1.0 cm; P < 0.05). Additionally, all other lines carrying introgressions at the same bin (corresponding to qVgt-9.03/4) showed a concordant direction of genetic effect (aIL = 0.5 cm; P < 0.10). The presence of the INDL QTL was confirmed in the F2 (aF2 = 2.1 cm). The lack of any detectable effect on PH at this chromosome region is probably caused by the balancing effect on PH due to a decrease of ND with a contemporary increase of INDL. Minor effect INDL QTLs were identified at bins 5.06/8 and 8.05/7 in the BC1, with Gaspé Flint providing the positive allele in both cases.
No EARN and PNDBE QTLs were detected in the three populations.
IL lines with multiple Vgtintrogressions
A number of IL lines were identified with trait values significantly different from B73 and carrying multiple introgressed Vgt QTLs. While their phenotypic values were not utilized to estimate the QTL effects, such lines are potentially useful for downstream analyses of QTL interaction or for marker-assisted applications. Examples of such lines are ILL25 (introgressions at qVgt-3.03 and qVgt-3.05/7), ILL28, ILL54, ILL55 and ILL57 (introgressions at qVgt-3.05/7 and Vgt1).
Qualitative traits
Genetic basis of flowering time in maize
The molecular dissection of quantitative traits is moving quickly from QTL to trait mapping, which is not only mapping and cloning one or few QTLs but rather the identification of all the major components responsible for the genetic variability of a given trait in a crop species. Buckler and co-workers [28], using the nested-association mapping approach identified ca. 50 QTLs for flowering time at relatively high-resolution. However, even if such QTL map information can now be linked directly to the maize genome sequence [29] and thus to candidate genes, the identification of the causal genes or sequence features (also known as quantitative trait nucleotides - QTN [30]) remains unsolved, and will still require the development of targeted cross populations for positional cloning.
The IL lines and the QTL results described here provide a starting point for the positional cloning of seven additional flowering time QTLs, similarly to what has been achieved for Vgt1. Although the genetic effects estimated for these Vgt loci were considerably smaller than the Vgt1 one (ca. a = 1.8 ND [22]), the Mendelization of even the smallest effect QTL (qVgt-4.04/5, a = 0.4 ND), assuming a single causal gene per locus, could be obtained by phenotyping the segmental nearly-isogenic lines for ND based on a low level of replication (ca. three, on an eight-plant plot basis).
The full genetic dissection of the phenotypic differences between B73 and Gaspé Flint undoubtedly suffered by the incomplete coverage of the Gaspé Flint genome (ca 70%) and by the partial genotyping. The incomplete coverage could have prevented the identification of additional flowering time QTLs while the partial genotyping could have precluded the identification of multiple introgressions within IL lines. The latter situation could have lead to both false positive (the effect was wrongly attributed to an introgressed chromosome region while it was actually due to a QTL laying into a hidden introgression) and false negative (the effect of an identified introgression was counterbalanced by the effect of a hidden one), or more generally to biased estimation of effects. Such drawbacks were at least partially prevented by carrying out parallel QTL analyses on the B73 × Gaspé Flint-derived BC1 and F2 populations. In this regard, the comparison of the results of the QTL analyses from the three populations showed that all flowering time QTLs (in terms of ND and DPS) highlighted within the BC1 and the F2 populations were identified in the analysis of the IL. Such QTLs were the strongest in terms of genetic effect estimated in the IL, making unlikely that additional major QTLs went unnoticed within the IL.
Several important biological questions can be addressed based on the availability of this IL. As previously observed [20, 23], we confirmed a high correlation between ND and DPS. Such correlation was also evident if direction and intensity of gene effect at the DPS and ND QTL are considered (Table 6). Correlation between two traits paralleled by the coincidence of QTLs and concurrent direction of QTL genetic effects have been recognized as indications of prevalent pleiotropy [31]. In our case, the causative QTNs at the flowering time QTLs would influence both ND and DPS. Because of the developmental architecture of cereals, this translates in allele variation influencing primarily ND and consequently DPS. However, linkage of different genes for ND and DPS at some of the flowering time QTLs cannot be excluded until molecular cloning of these QTLs will be accomplished. Additionally, we showed that QTLs for DPS were fewer than QTLs for ND and that QTLs for DPS coincided with QTLs for ND. Such observations imply that allelic variation at genes influencing the time of switch to the reproductive phase prevails over genetic variation for the rate of development (both plastochron and/or phyllochron, that is, the rate of phytomere differentiation and distension, respectively). Accordingly, genes known to be involved in maize plastochron (corngrass1/mir156 mapped on chr. 3, at 24.4 cM and PLA3/Vp8, mapped on chr. 1, at 243 cM [32, 33]) map outside the confidence interval of the Vgt QTLs. The lack of any QTL involved in plastochron/phyllochron is puzzling. Perhaps strong allelic variation for plastochron/phyllochron genes is not compatible with extreme earliness and satisfactory crop production, in such a way that strong plastochron/phyllochron new early alleles were (are) eliminated unconsciously during the domestication and/or the breeding processes. Alternatively, in the early phases of maize domestication and expansion, variation at such genes (at least between B73 and Gaspé Flint) was lost. It is noteworthy that three lines (ILL4, ILL12, and ILL44) were identified that showed delayed DPS without significant effect on ND. Unfortunately, the existence of such QTLs was not corroborated by multiple IL lines and by the BC1 and F2 QTL results. For these lines, the Gaspé Flint allele contributed the late allele. Altogether, the existence of Gaspé Flint alleles delaying DPS without affecting ND cannot be completely excluded. The observed delay in flowering time could result from i) a general slow plant development or ii) specific delay of tassel and/or flower development and anther extrusion.
As expected and previously observed [23], ND variation also tightly drove variation for PH (the more numerous the phytomeres, the higher the plant) and NDBE (if apical dominance is constant or independently controlled from ND, a change in ND will directly reflect to NDBE). Unexpectedly, ND variation (and therefore Vgt QTLs) also correlated with NDAE, with the ND vs. NDAE phenotypic correlation r = 0.88 (P < 0.01) (Table 5). One explanation is that NDAE (therefore the extension of the apical dominance signal) is related to plant height by the presence of a root- or crown-originated acropetal promoting-signal counterbalancing the apical dominance basipetally driven by auxin [34]. Alternatively, co-segregation for QTLs influencing apical dominance along with flowering time is possible. As a matter of fact, the NDAE effect detected in this study at bin 3.05/7 coincides with a QTL previously reported for the same trait [23, 35], and a well-supported candidate gene (barren stalk1 [36]). Additionally, the Lfy locus, influencing the number of leaves above the ear [37], maps on 3L [27].
Only bin 9.02/4 consistently showed an effect on INDL, based on IL and F2 QTL analyses. Interestingly, the gene Dwarf3, that codes for a P-450 cytochrome involved in gibberelline biosynthetic pathway [38] maps within such interval.
PH and INDL QTLs with positive Gaspé Flint allelic effect were identified in the BC1 and F2 populations and not in the IL (Additional files 4 and 5). Such result was likely the consequence of the residual heterozygosity of the BC1 and F2 populations, which drove the expression of heterotic effects on PH and INDL.
By producing and testing IL lines with introgressions at two or more loci, epistatic interactions among QTLs can be addressed in a (statistically) powerful way [39, 40]. Within the B73 × Gaspé Flint genetic background and for flowering traits, the presence of such interactions can be anticipated. The ND genetic effects of all Vgt QTLs under a fully additive mode summed to 14.7 nodes where the B73 - Gaspé Flint difference was 9.5 nodes; on the contrary Vgt QTL effects on DPS summed to 18.2 days, whereas the B73 - Gaspé Flint difference was 29.7 days. Such discrepancy is likely the consequence of multiple epistatic effects between different Vgt QTLs, which could reflect upon ND and DPS in different ways. However, additional causes could be (i) the segregation between B73 and Gaspé Flint of additional flowering loci lacking the strict ND-DPS pleiotropism and not represented within the IL, and (ii) the effect on the Gaspé Flint phenotypic mean value of a dominance component originated by the inherent Gaspé Flint heterozygosity.
Molecular bases of flowering time
This IL provides the opportunity to test the old hypothesis that the amount of nuclear DNA (C-value) influences flowering time. Maize genome size was shown to be negatively correlated with latitude and length of growing season [41, 42] and selection for earliness was linked with a reduction of C-values [43]. Similarly, a correlation was found between the presence of knobs (cytologically-detectable centromere-related chromosome regions, known to contain a large number of repeat units [44]) and delayed flowering time [45]. Gaspé Flint has been repeatedly shown to have one of the lowest C-values among the genus Zea [46] and to carry the least number of knobs-resident DNA repetitive elements in comparison with other investigated inbreds [47].
A number of coincidences of Vgt QTLs with flowering time QTLs mapped in other studies were found. Vgt1-Vgt2 and qVgt-10.04/5 coincided with two of the three highly recurrent consensus QTLs identified in a recent survey of 441 flowering time QTLs [48] and four Vgt QTLs (qVgt-1.05/6, Vgt1 and Vgt2, qVgt-9.03/4 an qVgt-10.04/5) overlapped with 'hot-spot' QTLs identified after QTL meta-analysis [49]. Additionally, all the other Vgt QTLs mapped at regions of relatively high QTL density [47]. Part of the explanation for such coincidence is likely the redundant use of B73 and related inbred lines as parents in many experimental populations [48].
Beside Vgt1, no other Vgt locus has been resolved at the level of candidate sequence and/or QTN. However, evidence of genes possibly involved in flowering time and corresponding to Vgt loci (based on comparative and/or fine mapping) have been collected in at least four studies. An FT-like gene, ZCN8, co-mapping with Vgt2 (bin 8.04) was proposed as candidate based on the FT strict homology and pattern of expression profile [50]. Glossy15, an Ap2-like gene closely related with ZmRap2.7 and shown to regulate the juvenility traits and the time to flowering [51] co-maps with qVgt-9.03. qVgt-1.05/6 overlaps with bif2, a gene for which natural allelic variation has been correlated with flowering time and node number [52] and with an SPL-like gene implicated with flowering time in Arabidopsis [23]. The region of qVgt-10.04/5 harbors a photoperiod-sensitive locus shown to include a CTT-like gene homologous to a heading-date gene of rice [25].
Genetics of adaptation to a short growing season environment
Our results showed that the extreme earliness of Gaspé Flint, if compared to standard Corn Belt lines, is due to allelic variation at several loci, generally detected in other crosses [48], one of which (Vgt1, in this study linked with Vgt2) with sizeable effect. As a next step, it would be valuable to verify to what extent Gaspé Flint earliness is due to the combination of early alleles commonly present in the maize germplasm or to unique early alleles. The first hypothesis seems to be supported by the results obtained from the positional cloning of Vgt1, the major of such flowering time QTLs. At Vgt1, Gaspé has been shown to carry a relatively common haplotype, shared even by medium-late Corn Belt dent lines [22], tropical germplasms and teosintes [53]. Additionally, the coincidence of the Vgt QTLs with many other flowering time QTLs supports the notion that Gaspé Flint alleles are present in other genetic backgrounds. Therefore, Gaspé Flint could be the prototype of an unconscious QTL-allele pyramidization process, carried out by pre-Columbian, Native American farmers to adapt a tropical species to cultivation at the northern limit of the temperate zone by recruiting alleles for earliness at a number of loci. The importance of the molecular verification of such hypothesis cannot be overemphasized, since QTL pyramiding is at the core of the current genomics-assisted breeding paradigm [5].
Nonetheless, it is possible that mutations contributing new early alleles arose uniquely in the gene-pool under selection for earliness, and such mutations remained confined in the Northern Flints. Recurrent mutation at the sugary1 locus has already been shown to have occurred during the process that led to the release of modern sweet maize inbreds and cultivars [54]. A high mutation rate was also hypothesized to be responsible for the linear response to selection for flowering time, in a selection experiment starting from a small, highly inbred maize population [55]. Additionally, the extreme plasticity of the maize genome caused by the activity of transposable elements at coding as well as at intergenic regions [56, 57] makes it likely that changes at the regulatory region of flowering time genes could have caused early flowering, and could have recurrently been selected. Reinforcing this hypothesis, Gaspé Flint was already reported to show an unusually high rate of spontaneous mutations [58]. If confirmed, such high mutation rate could have provided the unique early alleles upon which selection for earliness acted.
The adaptation of maize, a tropical species, to the northern latitudes, and the molecular changes enabling it, can be set in a rather precise timeframe. Maize was domesticated from teosinte in the Balsas basin of southern Mexico ca. 6,000 - 10,000 years ago [59], then reached south western United States ca. 3,000 years ago and northern United States and Canada only 1,000 years ago, at the time when the very well-defined maize race group, the Northern Flint, originated [18, 60]. The short early maize grown by the Penobscot Algonkins people in the Gaspé peninsula and described by the Canadian explorer Jacques Cartier in 1555 was likely Gaspé Flint [61]. The relatively late northward expansion of maize could have partially been caused by the complex genetic adaptations (e.g. extreme early flowering) required for the short growing season [18].
The genetic basis of maize flowering time was investigated using an introgression library developed using the virtually earliest maize cultivar, Gaspé Flint, and the elite reference inbred line B73. At least eight chromosome regions, including the well-known flowering time locus Vgt1, showed allelic variation influencing flowering time. These detected flowering time QTLs are involved in determining the number of vegetative phytomeres developed by the maize plant before switching to reproductive phase and do not appear to influence the rate of development (i.e.: plastochron/phyllochron). Thus, reducing the number of phytomeres seems to have been the key developmental feature enabling the adaptation of a tropical crop species like maize to much northern environments such as southern Canada. Thanks to the genetic constitution of the plant material (nearly isogenic lines) here described, all QTLs have been isogenized and are thus available for fine mapping. We anticipate that the availability of this introgression library will further contribute to the dissection and identification of the molecular bases of the rather impressive adapting plasticity of maize.
Plant material and production of the library
Gaspé Flint is an open-pollinated cultivar belonging to the Northern Flint germplasm race group [18] and characterized by extreme earliness, low stature, high tillering and multiple ears. Seed of Gaspé Flint was kindly donated by Ronald Phillips, University of Minnesota, St. Paul, USA. B73 is an elite inbred line belonging to the Iowa Stiff Stalk Synthetic heterotic group [62]. From the starting cross (B73 × Gaspé Flint), two F1 plants were utilized in a backcross with B73. Following the production of 88 B73 × (B73 × Gaspé Flint) BC1 plants, each plant was sampled for DNA extraction and profiled with 140 SSR markers (see below). Based on this molecular profiling, a set of heterozygous target chromosome regions (approximately one per BC1 plant), marked by two SSR flanking markers, were defined. From such plants, four additional generations of backcross using B73 as recurrent genotype were carried out, followed by three cycles of selfing. For each backcross or self generation and for each backcross family, approximately 20 plants were grown in the field and genotyped for the two markers flanking the target chromosome region. From BC2 to BC5, for each family, one plant (the one with more seed) heterozygous at the target region was advanced to the subsequent backcross generation. At the BC5 stage, plants heterozygous for the target introgression were selfed, producing BC5F2 seed. Plants of each BC5F2 family were screened with the assigned flanking SSR in order to identify and self plants (one per family) carrying the homozygous Gaspé Flint introgression. BC5F3 families were then grown and selfed for seed increase and storage. The plants utilized for this experiment corresponded to BC5F4 whereas available IL seed stocks correspond to BC5F4 or BC5F5.
Marker analysis
Genomic DNA was prepared from young leaf tissues as previously described [63]. A total of 180 SSR markers (Additional file 6) were utilized for searching polymorphisms between B73 and Gaspé Flint, 173 of which were informative and seven failed to do so. From the same set, SSR markers were selected for genotyping the IL. Primer information was downloaded from the Maize Genome Database at http://www.maizegdb.org. One additional marker, Vgt1-Mite, was utilized based on the information provided in [22]. PCR analyses for SSR were carried out as described [21] and separation and visualization followed standard agarose-gel electrophoresis protocols.
Genome coverage and features of the IL
Position for all markers as well as the length of chromosomes and introgressions are given in cM based on the maize reference map 'Genetic 2008' (available at http://www.maizegdb.org/map.php). Coverage of the IL was computed by summing unique Gaspé introgressions across the IL. Introgression start- and end-points were taken as the mid-points from/to the nearest evaluated markers or the telomeres. The same approach was used to estimate the proportion of the Gaspé genome polymorphic with B73 and not represented in the library. Chromosome regions containing four or more adjacent monomorphic SSR markers were also similarly sized and considered technically non-representable (see Results).
Production of the F2 and BC1populations and linkage maps
Along with the IL, an F2 population and a BC1 population were produced and utilized for linkage map construction and QTL analysis. The 88 (B73 × Gaspé Flint) × B73 BC1 plants corresponded to the ones used to establish the IL and were genotyped with 70 SSRs evenly spread on the 10 maize chromosome. Linkage map construction was carried out using JoinMap 3.0 [64], with a LOD threshold for linkage grouping of 3.0 and produced 10 linkage groups which covered 1278 cM (71% of the reference map). The B73 × Gaspé Flint F2 population included 65 plants and was genotyped with 26 polymorphic SSR markers covering maize chromosomes 1, 3, 8, 9 and 10. This linkage map covered 641 cM, corresponding to 78% of the same five linkage groups from the reference maize map 'Genetic 2008'. For the two maps, marker order was always in agreement with the one in the reference map.
Field experiment and collection of phenotypic data
All field experiments were carried out at the experimental station of the University of Bologna, near Cadriano (Lat.: N 44°33'03'', Lon.: E 11°24'36'', 33 m altitude), Italy. For the IL, 77 genotypes (75 IL lines, B73 and B73 × Gaspè Flint F1) were planted following a randomized complete block design, with four repetitions. Gaspé Flint was grown in adjacent plots and not included in the IL experiment because its reduced stature and vigor would have biased the phenotypic score of neighbouring plots. The experiment was planted on April, 20, 2006, in 1.4 m-long and 0.8 m-wide single-row plots, with eight plants per row, for a final density of 6.25 plants m-2. Nine phenotypic traits were recorded or computed (Table 1): number of days from planting to pollen shed (DPS) measured when 50% of the plants in a plot had extruded at least one anther; number of ears (EARN) per plant counted at flowering; growing degree units (GDU) as alternative score for flowering time as described (Equation 1 in [65]); number of plant nodes (ND), measured as total number of leaves at flowering (the 6th and 12th leaves were marked to account for the early developed leaves not visible at flowering); number of nodes below the top ear (NDBE) were counted with reference to the 6th and/or the 12th marks, including the leaf (node) of the top ear; number of nodes above the top ear (NDAE) were computed as ND - NDBE; proportion of nodes below the ear (PNDBE) was computed as NDBE/ND; plant height (PH) measured at the tip of the tassel; internode length (INDL) computed as the ratio PH/ND. The F2 population was grown contemporary and adjacent to the IL experiment, in plots of equal size. Phenotypic traits recorded or computed were the same as for the IL experiment. The BC1 population was planted on May 28, 2002, in 3 m-long and 1 m-wide plots, 0.2 m between plants (corresponding to 5 plants m-2). Phenotypic traits recorded or computed were DPS, EARN, GDU, INDL, ND and PH, as described for the IL experiment, while NDBE, NDAE and PNDBE were not considered.
Phenotypic data and QTL analyses
Normality of distribution for all trait values was tested by the Shapiro-Wilk test implemented in GenStat11 (VSN international Ltd, UK). For the IL data, ANOVA (Kruskall-Wallis for not normally distributed traits), phenotypic and genotypic correlations and heritability were computed using PLABSTAT version 3A [66]. IL line mean values for normally distributed traits (DPS, EARN, GDU, INDL, PH and PNDBE) were compared with the B73 mean values following a two-sided Dunnet's test as implemented in Statistica 8.0 (StatSoft, Inc.), with an alpha level of 0.05, while for non-normally distributed traits (ND, NDBE and NDAE) a Steel's test was carried out as implemented in GenStat11. We additionally tested for the presence of a QTL in a given chromosome interval by means of a "bin mapping" approach where IL lines sharing the same introgression were grouped and the trait mean value tested against B73. Because in several cases the same introgression was shared by several lines, such test for the presence of a QTL was expected to have more statistical power than the simple comparison of each single line with B73. For normally distributed traits, bin mapping was carried out by a two-sided t-test, assuming unequal variance, as described in [9]. For the non-normally distributed traits, the non-parametric Mann-Whitney U-test was adopted instead. Both the t- and the U-tests were carried out using GenStat11.
A QTL for a given trait was declared to correspond to a Gaspé Flint chromosome introgression (marked by SSR markers), when i) more than one IL line carrying such introgression significantly differed from B73 and no other Gaspè Flint introgression was shared by the same IL lines, or ii) a single IL line was significantly different from B73 and QTL evidence was obtained at the same chromosome region by the BC1 or the F2 QTL analyses with concordance of the genetic effect direction. In this case, correspondence was declared when the introgressed chromosome region and the 2-LOD support interval overlapped and the F2 and/or the BC1 QTL LOD peak was included in the IL introgression region. The genetic effect for each QTL was computed as (mILL - mB73)/2, were mILL was the mean value for the IL line(s) with a given introgression and mB73 was the B73 value.
For the BC1 and the F2 datasets, QTL analyses was carried out using Composite Interval Mapping as implemented in PLABQTL [67]. The default cofactor selection parameters (cov SELECT option with a log of the likelihood (LOD) score of > 3.0 to enter into the model) were used. The maps were scanned at 1-centimorgan (cM) intervals. LOD threshold for QTL significance (P < 0.05) were obtained after 1,000 permutations and ranged from 2.94 for PH in the F2 population to 3.20 for PNDBE in the BC1 population. The reported genetic effects and the proportion of phenotypic variance explained (PVE) by each QTL were obtained after fitting a multi-QTL model with the 'final simultaneous fitting' routine. QTL positions (corresponding to relevant introgression regions identified in the IL experiment and to the 2-LOD drop supporting intervals computed for the F2 and BC1 populations) were projected using MapChart 2.2 [68] with cM distances based on the maize reference map 'Genetic 2008' available at http://www.maizegdb.org. QTL nomenclature followed rules proposed by [69].
We thank Ronald Phillips for providing seed of Gaspé Flint and Matteo Ferri, Stefano Vecchi and Elena Govoni for technical support. We thank Francesca Ventura for providing meteorological data (temperature) for the GDU analysis. We acknowledge the contribution of the Interdepartmental Centre for Biotechnology, University of Bologna.
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When the arts and creativity are part of family life, as well as the classroom, everyone wins! Arts activities can deepen family bonds, provide lifelong memories, and enhance childrens' learning. Tips to spark your child's creativity and deepen their interest in the arts appear below. It's never too early…or too late to get started.
Tip 1: Create Time and Space for the Arts
Creating the time and space for your child to play music, perform, paint or draw, write a poem, or do other projects can help ignite their creative spark. Even if it's temporary, setting up a special spot for artistic activity is invaluable.
- Stock your child's creative space with musical instruments, markers, paper, costumes, or "found objectsFound object originates from the French objet trouvé, describing art created from undisguised, but often modified, objects or products that are not normally considered art, often because they already have a non-art function." that can be used in the art-making process.
- Make the space comfy and personal by decorating it with your child's art, framed photographs, or stuffed animals. Ensure the space is brightly lit.
- Create a supply basket or carrying-case so your kids can keep supplies organized and easily move them from room-to-room or take them on a trip.
- Don't rush! Make sure your child has regular downtime free of organized activities where they can make art, experiment, or just daydream. Kids need time to let their minds wander.
- Ensure that your kids can enjoy a messy, trial-and-error process of creating without worrying about "getting it right." Nothing inhibits creativity like too many restrictions—or too many people looking over their shoulders.
- Whether your child is just starting dance, music, or dram classes or hopes to become a "world-class" performer, the development of good practice habits is an art in itself. Establish a regular schedule and place to practice. Consider age appropriate ways to positively reinforce or encourage practice.
- Don't forget to set aside ample time for clean-up … just like they do at school.
Tip 2: Celebrate Your Child's Artwork and Artistic Process
The arts offer valuable opportunities for children, teens, and adults to express themselves and gain confidence in their abilities and ideas. They also provide great opportunities to share and reflect on what they know and think.
- Hang your child's artwork on a wall or refrigerator or create a "gallery space" and host a family exhibition. Make it a party!
- Talk to your kids about their artwork. Ask them questions about their dance, music, theater, and visual arts creations. Encourage them to talk about their artistic thinking and process.
- Try not to judge. Try saying, "Tell me about your sculpture" or "What was your inspiration for this song?" rather than "I love your painting," "What is that?," or "That doesn't really look like your sister."
- Failing"An essential aspect of creativity is not being afraid to fail." Edwin Land, inventor of the Polaroid camera & film is an essential part of the creative process. Children who are pressured to be perfect will sometimes stop trying new things because they didn't do it perfectly the first time around.
Remember, the process itself counts! Not every artistic product will be perfect or even "good." The process of creating the work—and the effort put into the process—is as valuable as the product.
Tip 3: Take Family Trips to Museums and Performances
Kids are never too young, or too old, to enjoy community events and cultural institutions, museums, theater, summer concerts, or childrens' film festivals. Just check first to make sure events are age-appropriate.
- Cultural institutions often offer low-cost or free family workshops or days to visit. Check out their websites or visit the site of your local arts council or department of cultural affairs for information on family events. Also, check with your child's school for free or discounted offers.
- Check for fun family arts activities around town in community and family newsletters, parent blogs, your local newspaper, or your town's website or Facebook page.
- Talk with your child about the experience before, during (when appropriate), and after. Share your thoughts, hear what they think, and be prepared to explore and learn in more depth after your visit.
Tip 4: Notice the Arts All Around...and Start a Conversation
Be on the lookout for art in public spaces. Parks, building lobbies, and subway stations often have murals, sculptures, and other art that can inspire imagination, conversation, and creativity.
- Ask your child what they notice and encourage them to ask questions about the art around you. You don't need to have all the answers. Ask open-ended questions, such as, "What do you see in that work of art?" or "What makes you say that?"
- Share art, dance, and music from your culture, as well as other cultures, with your children. Use the arts to celebrate and teach them about holidays, history, and cultural beliefs and practices.
- Encourage your kids to take photos when you are walking around the city, make sketches of what they see, or write a poem. Create a song or dance about their experiences.
- Look up—local architecture can be a source of wonder and inspire a passion for history and design.
- Be a role model. If you show an interest and appreciation for the arts and culture, your child is likely to make the arts a part of their lives.
Tip 5: Read With Your Children
As is true for all subject areas, reading is key to increasing knowledge and understanding and to fostering curiosity and good work habits. This is particularly true for the arts.
- Read picture and board books with your young children. Ask them to identify colors, shapes, objects, and more. Sing along with storybook songs and bring characters in the books to life with your voice, facial expressions, etc.
- Read with and encourage independent reading in your older children. Your kids are never too old to be read to, and reading to them is a great way to cap off a bedtime routine. Have them read to you as well.
- Ensure your kids read a mix of fiction and non-fiction. There are great books about musicians and artists that can serve as an inspiration to kids and young adults. Ask your local librarian for suggestions.
- Show your love of reading … by reading for yourself. Share stories with your children, fill your home with books, and make regular trips to the library.

subset: commoncrawl


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Do you take pleasure in making wreaths and other crafts? Do you may have a flair for design? Have you ever dreamed of beginning your own house-primarily based business? It may be that a house-based wreath making business is your good niche. I'm definitely saying that foreigners aren't allowed to work in Thailand with no permit by legislation. What I was stating is that many foreigners skirt the regulation by having a Thai companion run the front of the business while the foreigner (actual owner) runs the business in the background. In order that they don't have any need for a piece allow. I concur with this publish, it has some marvelous substance in it. I'd propose going and buying some modest dynamic USA and UK based mostly Twitter supporters from -usauk-twitter… as they offer high quality, shoddy and reasonable adherents for $1, $9 for one thousand devotees.
I just love the factor I do not like concerning the is battle every time. They are so misundersting within the human ought to unite we are not animals. Start with the packaged blanks and envelopes accessible on the craft stores. Experiment with them and see if card making is something you wish to do. We now have simply begun, a business journey here. My father has just bought a franchise of an English faculty in Koh Samui. I've been teaching right here for the final year so I suppose that is the natural progression! Common product lines on Amazon embody toys, child merchandise, sporting items, health, magnificence, clothes, groceries, DVDs, books, and consumer electronics. It now additionally provides e-book sales for the Kindle, Immediate Watch motion pictures, and MP3 downloads.
There are a number of inventive individuals on the market creating great work along with all the mass produced products on the market. You must make yourself stand out. This involves good advertising, promotion, branding, and of course good merchandise. When asked about this omission, they still just spoke about commerce unions and workers rights. That is what provides the media the opportunity to painting Labour as 'anti-business', whether or not it's true or not. Even major corporations go bankrupt as a result of they misunderstand the last two elements on the listing that do not appear as important. Nonetheless, I'll give a couple of examples as to why the final two fundamental success rules, can outweigh the more prominently known business needs.
Businesses which have gone public are topic to laws concerning their inner governance, resembling how government officers' compensation is decided, and when and the way information is disclosed to shareholders and to the general public. Within the United States, these rules are primarily applied and enforced by the United States Securities and Exchange Fee (SEC). Different Western nations have comparable regulatory bodies. The rules are implemented and enforced by the China Securities Regulation Commission (CSRC) in China. In Singapore, the regulation authority is the Monetary Authority of Singapore (MAS), and in Hong Kong, it is the Securities and Futures Commission (SFC).
My advice to somebody wanting into DS is to seek out one thing that you simply actually love and know that you may share with different individuals, not sell it to them, but share with them why you like it. I do fairs and occasions and I share with folks how wonderful these little hair clips are. I get enthusiastic about them and it reveals. ninety% of the women who strive them on, end up buying them because they love them. So find one thing you LOVE and never something simply to sell.


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$16T in debt and a president and elite media and voters demanding we squander yet more of our future. The Left, of course, has no future – they have no children. To expect them to care about freedom or liberty or property in a future in which they don't believe is foolish at best – and dangerous at worst.
I quote:
When in the course of human events, it becomes necessary for one people to dissolve the political bands which have connected them with another, and to assume among the powers of the earth, the separate and equal station to which the laws of Nature and of Nature's God entitle them, a decent respect to the opinions of mankind requires that they should declare the cases which impel them to the separation.
We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable rights, that among these are Life, Liberty and the Pursuit of Happiness — that to secure these rights, governments are instituted among men, deriving their just powers from the consent of the governed, that when any form of government becomes destructive of these ends, it is the right of the people to alter or abolish it. [emphasis mine]
It is time for the citizens of the Red States, the only states with growing populations and so a proven interest in the future of American freedom and liberty, to dissolve the bands that connect us with the subjects of the Blue States, those whose subjects demand to indebt the children of Red State citizens for the folly of Blue State policy, Blue States being in population decline nearly across-the-board.
Blue State voters do NOT believe in the future – so why are we paying them to devour our wealth, liberties and freedoms now? Why do we allow them to set policy for the future, from schools their nonexistent children will not attend – but ours will, to the environment in which their nonexistent children will not live – but ours will?
We two groups – Red and Blue – no longer believe in the same culture, philosophy, economics or laws. We no longer both believe in freedom, hard work, earned property… or America – which always has been more an idea than a geography.
No reason on earth exists for me to lower the standard of living of MY children to support the policies of a Progressive Left that is anti-American, anti-Liberty, anti-Freedom and anti-Property to its very core. Nor for ANY Conservative or Centrist parent to do so. Throughout history, the policies of Progressives have resulted in the destruction of nations, cities, communities, hopes, families and lives.
There are NO exceptions in the historical record.
We have wasted $13T dollars in Blue anti-poverty policies since 1964. The povery rate is the same. But we now are $16T in debt.
It is time to go. Sooner is better. And it is not written, anywhere, that our current state boundaries are sacred. CA, CO and other Blue states are, geographically, mostly Red counties. They, too, must separate for the sake of freedom and their childrens' futures.
At some point the question no longer is "If," but "when."
The "if" has been answered.
"Now" is the answer to "when."
It is time to go.


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Feb. 18, 2007
Box Score | Notes | AP Photo Gallery
Box Score in PDF Format
MINNEAPOLIS (AP) -The last time Ohio State was No. 1 in the AP men's basketball poll, John Havlicek, Jerry Lucas and a sub named Bob Knight were leading the Buckeyes to the NCAA championship game.
That was 45 years ago, but after Greg Oden and No. 2 Ohio State breezed to an 85-67 victory over Minnesota on Sunday, Hondo and the General might finally have some company.
Oden had 19 points nine rebounds and two blocks, Ron Lewis scored 16 points and Mike Conley Jr. finished with 10 assists and five steals for Ohio State, which is looking for its first No. 1 ranking since 1962.
"Right now it doesn't mean as much as it would at the end of March in the tournament," Conley said. "Regardless of what ranking we are – 1, 2, 3, 4 – it doesn't matter to us. We're trying to get better as a team and hopefully make a run."
The Buckeyes (24-3, 12-1 Big Ten) have won 11 in a row, with losses only to heavyweights Florida, North Carolina and Wisconsin this season.
Lawrence McKenzie scored 22 points for the Gophers (9-18, 3-10), but he didn't get near the help from his supporting cast that Oden did. The Gophers lost their fifth straight and 10th in their last 12.
The No. 1 ranking is up for grabs Monday after top-ranked Florida lost at Vanderbilt on Saturday night, but Ohio State isn't the only team to have a legitimate claim.
Third-ranked Wisconsin (26-2) is the only Big Ten team to beat the Buckeyes this year and travels to Columbus for a showdown with Ohio State next Sunday.
Fifth-ranked UCLA (23-3) also could make the jump to No. 1 after soundly beating No. 19 Arizona 81-66 on Saturday.
Being ranked No. 1 heading into selection day would give Ohio State the inside track on the top seed in the St. Louis bracket. Coach Thad Matta was asked after the game about the advantages of staying close to home as opposed to being seeded in, say, the Meadowlands.
"You just named sites and I didn't even know there were sites," Matta said. "Maybe it's superstitious of me, but if we start thinking about a seeding, my mind is not on this team and getting better."
Interim Gophers coach Jim Molinari has no such worries. His team looked to its past Sunday, not a tournament seeding.
Minnesota honored the 25th anniversary of its 1982 Big Ten championship team, bringing back such former players as Trent Tucker, Darryl Mitchell and Randy Breuer to be recognized in the second half.
Also in attendance was Detroit Pistons coach and Minnesota alum Flip Saunders, who was an assistant on that 1982 team. When he was introduced, Saunders was serenaded with chants of "We want Flip!" by a crowd hoping he leaves Motown to coach the Gophers next season.
Molinari is filling in after Dan Monson was fired seven games into this season, and Gopher basketball is reeling. Monson struggled mightily in recruiting, and the Gophers have been overmatched in most Big Ten games this season.
Sunday was no different.
"A lot of them are pros," Molinari said of the Buckeyes.
Ohio State took control early, scoring eight straight points to open a 14-7 lead in the first 6:30. But McKenzie came right back, scoring 13 points in a three-minute stretch to keep the Gophers in it. His three-point play pulled Minnesota within 24-23.
Oden was able to get position easily throughout the first half, but foul trouble kept him from taking over the game until the second half.
After McKenzie's three-point play, Oden backed down the 6-foot-9, 240-pound Bryce Webster with ease, then turned and dunked right over him as if he wasn't there. Webster responded by drawing Oden's second foul on the next possession down the floor, sending the 7-footer to the bench with 7:30 to play.
That's when Oden's high school teammate took over. Conley had a steal and layup to get things going, then added another steal and alley-oop pass to Lewis to give Ohio State a 38-26 lead.
"It felt good for that time when it was close," McKenzie said. "That's the same thing we have to sustain. … We have to do more than score in spurts."
The Buckeyes never looked back, and now they're looking toward a No. 1 ranking.


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Google's Indexation CapBlog Post: December 01, 2009
"...We've talked previously about metrics like a domain-level calculation of PageRank (Domain mozRank is an example of this). It's likely that Google would make this a backbone of the indexation cap estimate, as sites that tend to be more important and well-linked-to by other important sites tend to also have content worthy of being in the index...
-- will make me rethink my own opinions of PR...exceptional catch here!!!"
Agree with you JVRudnick


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I phoned Col. Chace at his home in Florida a couple of years ago. We talked for
about 30 minutes during which time I enjoyed his sense of humor that left me in stitches and his quick memory about certain events in Vietnam. When I referred to him as Col. Chace he quickly said, "Call me Stub." I thought about his request. I even tried it out on myself, silently saying, "Remember Stub when..." but I immediately realized that there was no way that I would have been able to address this man as anything but Col. Chace! He was my Commanding Officer in Vietnam and even though this conversation was happening 30 plus years after I'd been discharged from the USMC, I found that this man and officer continued to warrant that irrevocable status as SIR!
I doubt that Col. Chace was even aware of the respect that he still commanded but we continued our conversation and I found myself asking him if he remembered commanding a brief operation. We had moved a leper colony to a safer location. It was basically a relatively routine procedure. We took a handful of sniper rounds when we picked up the lepers but other than that it went smoothly. We successfully moved their colony to a new home but what remained in my memory over the years was that Col. Chace, CO of "B" Co. and then XCO of 3rd Amtrac Bn. went out on these operations with his men. A lot of us enlisted men in "B" Company thought this was one KICK ASS Marine.
I've been on the Colonel's email list now for a couple of years. He has shown his ongoing care for the people he writes. Col. Chace has also revealed a personal side of himself in these emails that many would never consider showing. His sense of humor is heart warming and I'm one Marine that feels very special not only to receive email from Col. Chace but to have followed him into battle while a radio operator with 3rd Amtrac Bn.
Did I ask Col. Chace's permission to put this here on this website? HELL NO I didn't! I wanted my feelings and I'm sure many other Marine's feelings who served under Col. Chace placed on the Internet. I'm fairly certain that if I asked him if he would mind if I put up a page like this, it would probably have embarassed him and I would have had to abide by his wishes when he asked me to remove it.
It's heart breaking to see "OUR" list of Amtracer's Online lose beloved Marines. I really needed to put this page up while Col. Chace is healthy, alive and with us. Any other Marines feel the same way about Col. Chace simply email me and I'll be very happy to place your comments right here.
I'm not a Marine, but I grew up with Col. Chace. His father was principal of our high school and we were in the same class. He's a great guy. We e-mail each other and sometimes he sends his Marine message to me too. He's a true hero. My grandson is at the Air Force Academy and I pray he turns into the kind of officer Frank was.
Thank you for appreciating him.
Marilyn Fowlie


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With our 37 year tradition of craftsmanship, Lithocraft takes pride in being recognized as a quality company. We are committed to providing high quality products and services through the continuous analysis and improvement of our processes and procedures.
If you are not currently a Lithocraft customer we welcome the opportunity to earn your business.
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The Gum Litter Taskforce (GLT) is part of a joint initiative that aims to achieve a long-term sustainable solution to the irresponsible disposal of chewing gum litter.
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April 02, 2018 Press
The Minister for Communications, Climate Action and Environment, Mr. Denis Naughten, T.D., and Food Drink Ireland (FDI) have today (April 2nd, 2018) announced the renewal of the negotiated agreement between the Department and the Chewing Gum Industry for a further three-year period (2018 - 2020). The initiative aims to build on the success of public awareness campaigns and education programmes to date, and introduce new elements to help raise awareness of the impact of gum litter and encourage proper gum disposal. The agreement represents a €10.2 million commitment by industry over a three-year period and includes new agreed mechanisms to further enhance and reinvigorate the campaign.
Welcoming the renewal of the agreement, Minister Naughten said:
"The agreement to renew this initiative for the three-year period to 2020 represents a genuine commitment by industry to finding a solution to improper gum disposal. Monitoring results since 2008 have demonstrated an improvement in gum litter levels over the course of each Gum Litter Taskforce campaign, with a consistent reduction in gum litter as a proportion of total litter from 30.8% in 2008, falling annually to a low of 11.2% in 2015, as measured by the National Litter Pollution Monitoring System Report. This demonstrates that the campaign has had a positive impact and I am confident that this new agreement will see further reductions in gum litter levels."
The renewed programme will continue to focus on achieving a lasting change in gum disposal behaviour, by encouraging people to put used gum in a bin. Several important elements will be continued, including the 'Bin It' school tour- a school educational workshop programme aimed at 14-16 year olds. The new agreement will also include a multi-media gum disposal messaging campaign, responsible chewing gum disposal messaging on packaging and standalone experiential events.
The programme is comprehensive and highly targeted in order to address the root cause of the problem. Acknowledging the industry's commitment to continuing to invest in tackling the issue of gum litter through research and development, the Minister said that he believes industry is genuinely committed to finding a solution to the particular problems caused by the improper disposal of chewing gum.
"This is a well thought out example of Government and industry working positively and constructively together to improve our environment to the benefit of all our citizens."
May 12, 2017 Press
Minister Denis Naughten today officially launched the Gum Litter Taskforce's gum litter education campaign in his native Roscommon.
The campaign has had huge success to date in changing the public's behaviour to gum disposal and in encouraging correct gum disposal through a targeted education awareness campaign. According to research carried out by Millward Brown on behalf of the Gum Litter Taskforce (GLT) during the 2016 campaign, the highest number of people to date (93%) agree that dropping gum is littering and almost six in seven people (84%) claiming they always dispose of their gum correctly.
Speaking at the official launch of the 2017 campaign, Minister for Communications, Climate Action and Environment Denis Naughten said: "It is always great to be involved with the Gum Litter Taskforce campaign and to launch this year's campaign here in my local constituency is particularly significant for me. Litter is a bugbear of mine. Gum litter like all litter is something we must work together on to eradicate. This campaign aims to change attitudes and behaviour when it comes to the disposal of used gum and to date it has seen very positive results. Complacency is not an option for any of us that are determined to see our environment and our communities free from litter. I hope this year's campaign enjoys just as much success as it did last year and it has my full support and that of the Government."
Also commenting on the launch, the Cathaoirleach Cllr. Tony Ward said: "This is a great initiative to bring communities together in support of this campaign both here in Roscommon and in towns across the country. The GLT campaign contributes significantly to the fight against gum litter and we're delighted to be a part of it again this year."
Paul Kelly, Chairman of the GLT added: "Each year the campaign seeks to educate people on the correct disposal of gum and while we have seen very positive results to date, we want to continue encouraging a positive behaviour change amongst the small minority who are still disposing of gum incorrectly. The latest research results highlighted a significant increase in those who say they never drop gum which points towards the success of the campaign since its inception at targeting younger people who are taking the message home with them and into households across Ireland. The national launch today is just one element of this nationwide campaign which also includes a national advertising campaign and a schools education programme, Bin It!"
Industry representative Alex West; Senior Manager, Corporate Affairs – UK & Ireland for the Wrigley Company (a subsidiary of Mars Inc) said: "The Wrigley Company is delighted to be the industry representative on the GLT and be part of such a successful campaign. The Gum Litter Taskforce is a unique industry funded initiative that runs in partnership with local and national government and civic society to tackle a common goal through awareness and education. The campaign results to date have demonstrated the success our approach has had in changing behaviour and attitudes to gum littering."
This is the third year of the latest campaign, the result of an agreement between the Department of Communications, Climate Action and the Environment and Food Drink Ireland (FDI) representing the gum industry, to fund a national gum litter awareness programme from 2015-2017.
Each of the local authorities will launch their own campaigns in the coming weeks. The 27 participating authorities are: Clare County Council, Longford County Council, Cavan County Council, Cork County Council, Cork City Council, Donegal County Council, Dublin City Council, Dun Laoghaire/Rathdown County Council, Fingal County Council, Galway City Council, Galway County Council, Kerry County Council, Kildare County Council, Kilkenny County Council, Laois County Council, Leitrim County Council, Louth County Council, Limerick City and County Council, Monaghan County Council, Roscommon County Council, Sligo County Council, Sough Dublin County Council, Tipperary County Council, Waterford County Council, Westmeath County Council, Wexford County Council and Wicklow County Council.
Email us here
+353 (0)1 605 1511
GLT Executive, Ibec, Confederation House 84-86 Lower Baggot Street, Dublin


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Ways to Volunteer
Check with your local Salvation Army (click to find the location nearest you) for specific details on volunteer opportunities in your area. There are so many ways you can volunteer with The Salvation Army—some of the most common ways are listed below.
Disaster Volunteering
Disaster Relief and Emergency Assistance is provided for fires, hurricanes, floods, and other devastating events. Volunteers help provide more than just meals and physical needs, they also help provide the emotional support needed in times of disaster. To become a Salvation Army Disaster Services Volunteer, you will need to register for training in advance.
Click here to learn about becoming a Disaster Relief Volunteer.
Year–Round Volunteering
Food Pantry
Food pantry organization and upkeep is needed all year. You could also support your local Salvation Army food pantry by donating non–perishable items.
Youth Activities
Character building youth programs which could use volunteers include music and arts school, as well as after school sporting and tutoring opportunities.
Holiday Volunteering
Holiday Meals
Volunteers serve meals at the Army Shelter or deliver meals to shut-ins on Thanksgiving and Christmas.
Holiday Food Boxes
Volunteers fill boxes with selected non-perishables.
Angel Tree
Individuals, families, and groups select a child (ages 1-13) or senior (age 55 and older) for whom they provide a special Christmas.
Kettle Campaign
The money raised during the Kettle Campaign helps pay for all the Christmas programs listed here as well as other needs through the year. Contact your local Salvation Army location to sign up to ring a bell. Bell ringers are always needed, or consider creating an Online Red Kettle and share your kettle's link and #RedKettleReason on social media to encourage your friends and family to join you in giving!


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Purchasing property in the West End is a major transaction, but Globe Apartments can make the process simple and convenient. Providing a bespoke and personal service to suit any buyer or seller's needs, Globe have a dedicated team on hand to help with all your questions and make your home ownership dreams come true.
Please call us on +44 (0) 207 935 9512 or email email@example.com if you are interested in buying or selling a house or a flat in London's West End, to discuss how we can market and sell your property, or assist in your purchase.
Thinking of selling?If you own a leasehold property, do you know how long is left on your lease?
Globe Apartments' affiliate company, myleasehold ltd, are Chartered Valuation Surveyors specialising in residential lease extensions and freehold purchases.
Call today for a free 10 minute consultation.


text: I've noticed some very odd mileage and Wh/mi readouts on my dash recently, with mileage numbers jumping up seemingly randomly and energy use numbers that diverge beyond explanation. If I fully charge, unplug, and start driving immediately, the "Since XX:XX AM" and "Since Last Charge" readouts should be identical (or at least close to it), no? Here are some readouts from this morning, driving at roughly 70 MPH: 9:01 AM, Odometer 54,428: Since 8:27 AM: 41.2 mi, 34 min, 302 Wh/mi Since Last Charge: 35.4 mi, 9.7 kWh, 273 Wh/mi 9:02 AM, Odometer 54,430: Since 8:27 AM: 41.2 mi, 35 min, 302 Wh/mi Since Last Charge: 41.9 mi, 11.4 kWh, 273 Wh/mi 9:06 AM, Odometer 54,433: Since 8:27 AM: 41.3 mi, 38 min, 302 Wh/mi Since Last Charge: 41.9 mi, 11.4 kWh, 273 Wh/mi 9:09 AM, Odometer 54,438: Since 8:27 AM: 45.9 mi, 42 min, 304 Wh/mi Since Last Charge: 50.1 mi, 13.8 kWh, 276 Wh/mi - Why is the "Since 8:27 AM" Wh/mi reading about 10% higher than "Since Last Charge"? My last charge was at 8:27 AM, so shouldn't they be the same? Which is more accurate? - The odometer seems to be going up normally, so why aren't the distances provided on the dash going up at the same rate? I'd understand if there was just a lag in that the distance updated only once every X seconds, but sometimes the distance goes up 0.1 miles, other times it jumps up several miles in an instant. Sometimes the "Since Last Charge" is way ahead, other times its way behind. What is going on here? I love the car (54,000 miles and going strong on a software-limited 40 kWh), but this just seems...weird...and makes me question other values displayed (e.g. range remaining).


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I just bought these (in the sale at Schuh!):
And boy are they comfy! They are squishy inside so it's like walking on rubber, which you are actually – it's latex, a natural rubber. In fact everything about these trainers is great, from the comfort factor to the ribbon laces to the fact that they are completely ethically produced.
Here's what the inside of the box tells me about the ingredients of my new shoes:
Latex (as mentioned just now)
Recycled car tyres – 'we collect used and landfill-bound car tires, cut them up and use them as outsoles.
Bamboo – bamboo is an endless resource because it is so plentiful. It's super soft too!
Organic cotton – Our cotton is 100% organic – that means no synthetic pesticides, fertilizers or additives.
Water based glue – we use all water based glues. Better for the shoe makers and better for you.
Crepe – crepe is another natural rubber. It's tapped from the hevea tree in the same way maple syrup is tapped from the maple tree.
Recycled inner tubes – we reuse the rubber from landfill bound car tire inner tubes on many of our shoes.
Hemp – not only is hemp soft but it is one of the wtrongest vegetable fibres available and it grows like a weed!
They call their brand 'shoes for a happy planet'. Happy me, too.


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Θοδωρής & Ρένα
What can you say about this couple? You can see the love in their eyes when they look at each other. Their smile is endless and friends together with the family is responsible for that. True happiness is all around them!! Enjoy the love and happiness!Read More


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2019 Australian Grand Prix: Pre-Race Press Conference
The first pre-race conference of the 2019 season was centred on the sad loss of FIA race director Charlie Whiting, who passed in the early hours of Thursday morning. Listen in as the drivers pay their respects, and also look ahead to the race weekend's action. For more F1® videos, visit http://www.Formula1.com Like F1® on Facebook: https://www.facebook.com/Formula1/ Follow F1® on Twitter: http://www.twitter.com/F1 Follow F1® on Instagram: http://www.instagram.com/F1 #F1 #AusGP


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Have an question? Call 310-hire
Have an question? Call 310-hire
There is a growing need for assistance with homeless persons, children with special needs, and those with substance abuse problems. Growth is also expected in the area of First Nations outreach and community development, especially for youth and those in rehabilitation. Employment opportunities are much better for those who have appropriate post-secondary education.
Community and social service workers administer and implement a variety of social assistance programs and community services (life skills workshops, substance abuse treatment programs, and other community and social service programs). They assist clients in dealing with personal and social problems. They are employed by social service and government agencies, group homes, correctional facilities, and other establishments.
Community and social service workers may interview clients to obtain their case histories and other background information. They may prepare intake reports, assess their clients, and investigate their eligibility for social benefits. If necessary, they will refer their clients to other social services. Later, they meet again with their clients to assess their progress, give them support, and discuss any difficulties or problems. Community and social service workers may work in schools as para-professionals assisting with children with special needs along side occupational therapists or provide respite for families with children with special needs.
This work is done under the supervision of social workers or health care professionals. They also can assist in evaluating the effectiveness of these treatment programs by tracking clients' behavioural changes and responses to interventions. Community and social service workers maintain contact with other social service agencies involved with their clients to provide information and to obtain feedback on clients' overall progress.
Note: Students have the option of taking two 100 hour practicums (CS500 and CS600) or one 200 hour practicum (CS700) to fulfill the program work experience hours.
Learning Objectives
Practicum may include any shifts other than day shift (i.e. evenings – 3 to 11 pm or nights – 11 pm to 7 am and possible weekends).
Students are responsible for their own transportation to and from designated offsite training and practicum sites.
Practicum training is conducted in shifts of a minimum of 5 hours per day for a total of 100 hours or 4 weeks.
Placement sites are subject to availability.
Practicum sites may require more current CRC and TB testing (to be done at student's expense)
This program includes the Nonviolent Crisis Intervention© Seminar using the Crisis Prevention Institute, Inc. curriculum and certified training. All students will be able to take the exam to become Blue Card™ endorsed.
My name is Caroline. I am an army wife and mother of two teenagers. Most of my adult life has … Read More
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Before starting school I was extremely unsatisfied with the employment options available without furthering my education. While attending Sprott Shaw … Read More
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