ABSTRACT. Objective. To compare the ages, by gender, at which normally developing children acquire individual toilet-training skills and to describe the typical sequence by which children achieve complete toileting success.Methods. A longitudinal survey was conducted of a cohort of children who were 15 to 42 months of age and attending 4 pediatric practices in the Milwaukee area (2 inner city and 2 suburban) from 1995 through 1997. Parents completed background surveys, and each child's development was assessed using the Bayley Scales of Infant Development II. Each week for 12 to 16 months, parents completed a training status survey (TSS). The TSS, designed for this project, included information on daily toilet-training status (eg, number of urine successes on a 5-point scale) and 28 weekly toilet-training behaviors rated on a 5-point Likert scale from 1 (never) to 5 (always). Children were considered to have acquired a particular skill when they received a rating of 4 or 5 on the TSS scale. The median age and interquartile range for children for each toilet-training skill are reported for girls and boys separately using survival curve analysis. Ages at which each gender achieved these skills are compared using a log-rank test.Results. The study included 126 girls and 141 boys; 88% were white. Parents submitted a total of 10 741 weekly surveys (range: 1-73; median: 49 per child). Girls demonstrated toilet-training skills at earlier ages than boys. The median ages for "staying dry during the day" were 32.5 months (95% confidence interval: 30.9 -33.7) and 35.0 months (95% confidence interval: 33.3-36.7) for girls and boys, respectively. The median ages for readiness skills for girls and boys, respectively, were as follows: "showing an interest in using the potty," 24 and 26 months; "staying dry for 2 hours," 26 and 29 months; "indicating a need to go to the bathroom," 26 and 29 months. There was a marked concordance in the sequences in which girls and boys achieve individual skills. In addition, the interquartile ranges of the toileting skills varied from 6.9 to 11.4 months in girls and from 7.5 to 14.6 months in boys.Conclusions. In this study population, girls achieve nearly all toilet-training skills earlier than boys, including successful completion. Most children do not master the readiness skills until after the second birthday. T he medical literature on toilet training is woefully deficient. Toilet training is a universally acquired skill for normally developing children, yet there is no information about the requisite skills that children learn sequentially, beginning with the signs of readiness and ending with successful completion of toileting.Current pediatric literature stresses the importance of the child's readiness before initiating toilet training. 1-3 Despite this perceived importance, a commonly used developmental screening test in general pediatrics does not reference any specific toilet-training skills. 4 A critical review of the literature reveals 2 broad categories of readiness skills: global...

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Time and circumstances for the disappearance of Neanderthals and its relationship with the advent of Modern Humans are not yet sufficiently resolved, especially in case of the Iberian Peninsula. Reconstructing palaeoenvironmental conditions during the last glacial period is crucial to clarifying whether climate deteriorations or competition and contacts with Modern Humans played the pivotal role in driving Neanderthals to extinction. A high-resolution loess record from the Upper Tagus Basin in central Spain demonstrates that the Neanderthal abandonment of inner Iberian territories 42 kyr ago coincided with the evolvement of hostile environmental conditions, while archaeological evidence testifies that this desertion took place regardless of modern humans’ activities. According to stratigraphic findings and stable isotope analyses, this period corresponded to the driest environmental conditions of the last glacial apart from an even drier period linked to Heinrich Stadial 3. Our results show that during Marine Isotope Stages (MIS) 4 and 2 climate deteriorations in interior Iberia temporally coincided with northern hemisphere cold periods (Heinrich stadials). Solely during the middle MIS 3, in a period surrounding 42 kyr ago, this relation seems not straightforward, which may demonstrate the complexity of terrestrial climate conditions during glacial periods.

The appearances of palaeosurfaces intercalated into palaeo-dune fields on Fuerteventura are multifaceted. Although reddened layers in these dune sediments might suggest that strong soil-formation processes have taken place, the combination of aridity and parent material, namely biogenic carbonate sand of shelf origin, reveals that strong soil formation seems unlikely. These sediments rather represent de- and recalcification processes only. Solely in the case of admixed material of volcanic origin and dust deposits further soil-forming processes seem to be possible. Hematite-rich Saharan dust contributes to reddish colouration of the palaeosurfaces. In addition, CaCO3-coated iron particles appear to be ingredients of dust being leached after deposition and transformed to hematite. Overall, we propose much weaker soil-forming processes during the Pleistocene than previously postulated. Our findings support the relevance of local environments. Carbonate sands of shelf origin hinder strong soil formation and the reddish layers separating dune generations are palaeosurfaces, which mainly consist of Saharan dust. After deposition of allochthonous material, these layers are overprinted by weak soil-forming processes. The formation of palaeosurfaces primarily depends on morphodynamically stable periods during limited sand supply. Our data suggest a cyclicity of processes in the following order: (1) sand accumulation, (2) dust accumulation and weak soil formation, and (3) water-induced erosion. For the Canary Islands, we support the assumption of glacial maxima being periods of increased levels of moisture. In combination with rising sea level, we propose that favorable conditions of surface stability occur immediately after glacial maxima during periods of starting transgression, whereas regression periods immediately after sea-level high stands seem to yield the highest sand supply for the study area.

The formation of loess deposits strongly depends on the availability of deflatable dust-sized material. Identification of source areas and mechanisms of dust production is essential for an appropriate characterization of related palaeoenvironmental conditions. So far, little research has been done on loess deposits in the Mediterranean region and information about mechanisms of dust production is very rare. In this context, it is not clear from where the loess deposits from the upper Tagus Basin in central Spain originated. The main objective of this study was to find out whether these loess deposits were formed primarily by mountain processes and fluvial comminution, or whether they have their origin in the weathering of Tertiary marls in the centre of the Madrid Basin. A further concern was to link the determined source areas with loess formation mechanisms and concomitant environmental contexts. Following a comprehensive approach using heavy minerals and grain-size data, together with information on stratigraphic features and geomorphic positions, different local loess sources could be identified. This study shows that during the last 35 kyr a major proportion of the Tagus loess deposits was deflated from river floodplains, while the mountain region of the Iberian Range was identified as a significant source of respective floodplain sediments. Based on heavy mineral compositions and dating results, it was found that during Heinrich Stadial 3, sediment supply from the Iberian Range strongly increased, suggesting an environmental shift from initially warmer towards colder temperatures in late Marine Isotope Stage 3. Furthermore, it was found that grain-size patterns clearly indicate maximum wind strengths during Heinrich Stadial 3, followed by Heinrich Stadial 2 and Heinrich Stadial 1. These results demonstrate that the formation of dustsized particles in this part of the Mediterranean operated similar to many other places in temperate and continental regions, and that weathering processes linked to hot and dry environments were only of minor importance.