The human occupation history of Southeast Asia (SEA) remains heavily debated. Current evidence suggests that SEA was occupied by Hòabìnhian hunter-gatherers until ~4000 years ago, when farming economies developed and expanded, restricting foraging groups to remote habitats. Some argue that agricultural development was indigenous; others favor the "two-layer" hypothesis that posits a southward expansion of farmers giving rise to present-day Southeast Asian genetic diversity. By sequencing 26 ancient human genomes (25 from SEA, 1 Japanese Jōmon), we show that neither interpretation fits the complexity of Southeast Asian history: Both Hòabìnhian hunter-gatherers and East Asian farmers contributed to current Southeast Asian diversity, with further migrations affecting island SEA and Vietnam. Our results help resolve one of the long-standing controversies in Southeast Asian prehistory.

Although free-cement-based alkali-activated paste, mortar, and concrete have been recognised as sustainable and environmental-friendly materials, a considerable amount of effort is still being channeled to ascertain the best binary or ternary binders that would satisfy the requirements of strength and durability as well as environmental aspects. In this study, the mechanical properties of alkali-activated mortar (AAM) made with binary binders, involving fly ash (FA) and granulated blast-furnace slag (GBFS) as well as bottle glass waste nano-silica powder (BGWNP), were opti-mised using both experimentally and optimisation modelling through three scenarios. In the first scenario, the addition of BGWNP varied from 5% to 20%, while FA and GBFS were kept constant (30:70). In the second and third scenarios, BGWNP (5–20%) was added as the partial replacement of FA and GBFS, separately. The results show that the combination of binary binders (FA and GBFS) and BGWNP increased AAM’s strength compared to that of the control mixture for all scenarios. In addition, the findings also demonstrated that the replacement of FA by BGWNP was the most significant, while the effect of GBFS replacement by BGWNP was less significant. In particular, the highest improvement in compressive strength was recorded when FA, GBFS, and BGWNP were 61.6%, 30%, and 8.4%, respectively. Furthermore, the results of ANOVA (p values < 0.0001 and high F-values) as well as several statistical validation methods (R > 0.9, RAE < 0.1, RSE < 0.013, and RRSE < 0.116) confirmed that all the models were robust, reliable, and significant. Similarly, the data variation was found to be less than 5%, and the difference between the predicted R2 and adj. R2 was very small (<0.2), thus confirming that the proposed non-linear quadratic equations had the capability to predict for further observation. In conclusion, the use of BGWNP in AAM could act as a beneficial and sustainable strategy, not only to address environmental issues (e.g., landfill) but to also enhance strength properties.

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61. CC-BY-NC-ND 4.0 International license It is made available under a was not peer-reviewed) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity.The copyright holder for this preprint (which . http://dx.doi.org/10.1101/278374 doi: bioRxiv preprint first posted online Mar. 8, 2018; and directly test the two competing hypotheses. We find that early genomes from Asian phenotypic affinity, suggesting that human diversity in SEA was strongly influenced by 82 population expansions from the north (4). Yet, the extent to which the movements from East 83 Asia (EA) impacted on the genetic and cultural makeup of the people of SEA remains 84 controversial. 85Two distinct population models have been proposed to account for the biological and was not peer-reviewed) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. hybridisation to baits that cover the entire mappable human genome (15). 119We performed comparative testing of three different capture approaches for human was not peer-reviewed) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity.The copyright holder for this preprint (which . http://dx.doi.org/10.1101/278374 doi: bioRxiv preprint first posted online Mar. 8, 2018; Biosciences) -with the aim of applying the most effective method to ancient human remains 124 from tropical SEA (SOM1). We found a modified version of MYbaits Whole Genome 125Enrichment to be the best-performing method. We applied this method, in combination with 126 shotgun sequencing approaches where sufficient endogenous DNA allowed it, to samples from 127 Malaysia, Thailand, Philippines, Vietnam, Indonesia and Laos, dating between 0.2 and 8 kya 128 (SOM2). We obtained 25 low-coverage ancient genomes (Table 1), along with mtDNA and 129 nuclear DNA from an additional set of 16 individuals (Table S3), belonging to hunter-gatherers 130 from the Hoabinhian culture, as well as Neolithic, Bronze Age and Iron Age farmers (SOM3). 131All samples showed damage patterns typical of ancient DNA (38) ( Table S3). 132To address the genetic relationships among the ancient individuals, we performed a constructed solely with present-day samples (40) (SOM4). We then used ADMIXTURE (41) 136 to find reference latent ancestry components that could best fit our present-day data, and then Vietnam, Laos and Thailand) populations, along with a broad East Asian component. 152We used outgroup f3 statistics (f3(Mbuti;X,Ancient samples)) to determine which 153 populations have the highest levels of shared drift with each of the ancient individuals (SOM6). 154. CC-BY-NC-ND 4.0 International license It is made available under a was not peer-reviewed) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity.The copyright holder for this preprint (which . http://dx.doi.org/10.1101/278374 doi: bioRxiv preprint first posted online Mar. 8, 2018; Group 1 shares the most drift with certain ancient mainland samples ( ...