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Archaeological sites in northern Africa provide a rich record of increasing importance for the origins of modern human behaviour and for understanding human dispersal out of Africa. However, the timing and nature of Palaeolithic human behaviour and dispersal across north-western Africa (the Maghreb), and their relationship to local environmental conditions, remain poorly understood. The cave of Rhafas (northeast Morocco) provides valuable chronological information about cultural changes in the Maghreb during the Palaeolithic due to its long stratified archaeological sequence comprising Middle Stone Age (MSA), Later Stone Age (LSA) and Neolithic occupation layers. In this study, we apply optically stimulated luminescence (OSL) dating on sand-sized quartz grains to the cave deposits of Rhafas, as well as to a recently excavated section on the terrace in front of the cave entrance. We hereby provide a revised chronostratigraphy for the archaeological sequence at the site. We combine these results with geological and sedimentological multi-proxy investigations to gain insights into site formation processes and the palaeoenvironmental record of the region. The older sedimentological units at Rhafas were deposited between 135 ka and 57 ka (MIS 6 -MIS 3) and are associated with the MSA technocomplex. Tanged pieces start to occur in the archaeological layers around 109 ka, which is consistent with previously published chronological data from the Maghreb. A well indurated duricrust indicates favourable climatic conditions for the pedogenic cementation by carbonates of sediment layers at the site after 57 ka. Overlying deposits attributed to the LSA technocomplex yield ages of ~21 ka and ~15 ka, corresponding to the last glacial period, and fall well within the previously established occupation phase in the Maghreb. The last occupation phase at Rhafas took place during the Neolithic and is dated to ~7.8 ka.

Women scholars have contributed to the study of loess. Charlotte Hibbert made the first map of loess distribution and there were many subsequent achievements. The twenty people selected represent a subjective choice; there is no overall biobibliographical metric that can be applied. The twenty are mss: Hibbert, Owen, Swineford, Conea, Marković-Marjanović, Fotakieva, Ivanova, Davin, Coude-Gaussen, Wintle, Matviishina, Gerasimenko, Billard, Grabowska-Olszewska, Sycheva, Mavlyanova, Rendell,Łanczont, Klukanova, Morozova. The INQUA Loess Commission provides a convenient temporal divide, and also a divide in style of loess investigation: early studies pre-Commission; Loess Commission activities; modern scientific loess research post-Commission (after 2003).

The Messinian lagoonal carbonate–evaporite sequence of Cyrenaica, north‐east Libya, hosts: (i) opaline nodules in gypsiferous microbial‐rich mudstone; (ii) nodules replacing poikilotopic gypsum cementing bioclastic carbonates; and (iii) bedded porcelanite with large lenticular gypsum pseudomorphs intercalated with recrystallized microbial mats. Optical microscopy, scanning electron microscopy, backscattered electron images – secondary electron images, X‐ray fluorescence, X‐ray diffraction and cathodoluminescence techniques were employed to elucidate on the early stages of chert diagenesis and demonstrate the role of moganite in the formation of varieties of chalcedony during silicification. The opaline nodules composed of opal‐A, exhibit shrinkage cracks lined by isopachous fibrous quartzine underlain by a thin birefringent zone. This suggests that quartzine may develop by crystallization and conversion of opal‐A through a transitional moganite. The quartzine is followed by amorphous silica gel that converts into length‐fast chalcedony. By contrast, lutecite evolved by silica replacement of gypsum through a transitional moganite phase, which forms an amorphous zone in apparent optical continuity with the fibrous lutecite; as moganite advances by pseudo‐crystalline terminations controlled by the gypsum cleavage. In gypsified oyster shells, intercrystalline organic matter enveloping pseudomorphed shell microstructures enabled moganite nucleation that merges syntaxially around the gypsum crystal rim. The associated lutecite occurs as radial‐fibrous beekite aggregates that are consistent with early shell silicification. The bedded porcelanite consists of opal‐CT groundmass undergoing recrystallization and enclosing micro‐cavities lined by quartzine. The associated pseudomorphs display phases of gypsum replacement by moganite and lutecite at the outer margin, followed by dissolution and cavity filling by quartz varieties in response to fluid flushing. In all cases, organic matter and microbes played a vital role in the silicification process. [ABSTRACT FROM AUTHOR]

Abstract Background Children with poor motor ability have been found to engage less in physical activities than other children, and a lack of physical activity has been linked to problems such as obesity, lowered bone mineral density and cardiovascular risk factors. Furthermore, if children are confident with their fine and gross motor skills, they are more likely to engage in physical activities such as sports, crafts, dancing and other physical activity programs outside of the school curriculum which are important activities for psychosocial development. The primary objective of this project is to comprehensively evaluate a whole of class physical activity program called Animal Fun designed for Pre-Primary children. This program was designed to improve the child's movement skills, both fine and gross, and their perceptions of their movement ability, promote appropriate social skills and improve social-emotional development. Methods The proposed randomized and controlled trial uses a multivariate nested cohort design to examine the physical (motor coordination) and psychosocial (self perceptions, anxiety, social competence) outcomes of the program. The Animal Fun program is a teacher delivered universal program incorporating animal actions to facilitate motor skill and social skill acquisition and practice. Pre-intervention scores on motor and psychosocial variables for six control schools and six intervention schools will be compared with post-intervention scores (end of Pre-Primary year) and scores taken 12 months later after the children's transition to primary school Year 1. 520 children aged 4.5 to 6 years will be recruited and it is anticipated that 360 children will be retained to the 1 year follow-up. There will be equal numbers of boys and girls. Discussion If this program is found to improve the child's motor and psychosocial skills, this will assist in the child's transition into the first year of school. As a result of these changes, it is anticipated that children will have greater enjoyment participating in physical activities which will further promote long term physical and mental health. Trial registration This trial is registered in the Australian and New Zealand Clinical trials Registry (ACTRN12609000869279).

2005, Past Human Activity and Geomorphological Change in a Guano-Rich Tropical Cave Mouth: Initial Interpretations of the Late Quaternary Succession in the Great Cave of Niah, Sarawak. Asian Perspectives: Journal [...]