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Recent excavations at the early Middle Pleistocene site of Mata Menge in the So'a Basin of central Flores, Indonesia, have yielded hominin fossils (1) attributed to a population ancestral to Late Pleistocene Homo floresiensis (2). Here we describe the age and context of the Mata Menge hominin specimens and associated archaeological findings. The fluvial sandstone layer from which the in situ fossils were excavated in 2014 was deposited in a small valley stream around 700 thousand years ago, as indicated by [sup.40]Ar/[sup.39]Ar and fission track dates on stratigraphically bracketing volcanic ash and pyroclastic density current deposits, in combination with coupled uranium-series and electron spin resonance dating of fossil teeth. Palaeoenvironmental data indicate a relatively dry climate in the So'a Basin during the early Middle Pleistocene, while various lines of evidence suggest the hominins inhabited a savannah-like open grassland habitat with a wetland component. The hominin fossils occur alongside the remains of an insular fauna and a simple stone technology that is markedly similar to that associated with Late Pleistocene H. floresiensis., Mata Menge is located near the northwestern margin of the So'a Basin, a ~400[km.sup.2] geological depression in central Flores (Fig. 1). The basement substrate consists of the Ola Kile Formation [...]

New excavations in Sulawesi, where in situ stone artefacts associated with fossil remains of megafauna have been recovered from stratified deposits between 200,000 and 100,000 years ago, suggest that Sulawesi was host to a long-established population of archaic hominins. Sulawesi is the largest and oldest island within Wallacea, a vast zone of oceanic islands separating continental Asia from the Pleistocene landmass of Australia and Papua (Sahul). By one million years ago an unknown hominin lineage had colonized Flores immediately to the south.sup.1, and by about 50 thousand years ago, modern humans (Homo sapiens) had crossed to Sahul.sup.2,3. On the basis of position, oceanic currents and biogeographical context, Sulawesi probably played a pivotal part in these dispersals.sup.4. Uranium-series dating of speleothem deposits associated with rock art in the limestone karst region of Maros in southwest Sulawesi has revealed that humans were living on the island at least 40 thousand years ago (ref. 5). Here we report new excavations at Talepu in the Walanae Basin northeast of Maros, where in situ stone artefacts associated with fossil remains of megafauna (Bubalus sp., Stegodon and Celebochoerus) have been recovered from stratified deposits that accumulated from before 200 thousand years ago until about 100 thousand years ago. Our findings suggest that Sulawesi, like Flores, was host to a long-established population of archaic hominins, the ancestral origins and taxonomic status of which remain elusive., Author(s): Gerrit D. van den Bergh [sup.1] [sup.2] , Bo Li [sup.1] , Adam Brumm [sup.3] [sup.4] , Rainer Grün [sup.3] , Dida Yurnaldi [sup.1] [sup.5] , Mark W. Moore [...]

Tools of the trade The brain of Homo floresiensis, the small hominids popularly known as 'hobbits', was so small that the species' capacity for stone tool manufacture has been questioned. Instead, it is argued that modern humans made the stone tools found in association with H. floresiensis in Liang Bua cave, in western Flores, Indonesia. Now a new study of 840,000-year-old stone artefacts from Mata Menge in central Flores points to an immigration of toolmakers to the region long before Homo sapiens existed. These tools are similar to the much more recent artefacts found at Liang Bua, suggesting continuity, and probable tool-making abilities for H. floresiensis. Stylistic similarities of stone tools recovered from 800,000-year-old deposits in Flores with stone tools associated with the much later Homo floresiensis suggest continuity -- calling into question claims that the brain of Homo floresiensis was too small to have accommodated technology. In the Soa Basin of central Flores, eastern Indonesia, stratified archaeological sites, including Mata Menge, Boa Lesa and Kobatuwa (Fig. 1), contain stone artefacts associated with the fossilized remains of Stegodon florensis, Komodo dragon, rat and various other taxa. These sites have been dated to 840-700 kyr bp (thousand years before present).sup.1. The authenticity of the Soa Basin artefacts and their provenance have been demonstrated by previous work.sup.2,3,4,5,6, but to quell lingering doubts.sup.7, here we describe the context, attributes and production modes of 507 artefacts excavated at Mata Menge. We also note specific similarities, and apparent technological continuity, between the Mata Menge stone artefacts and those excavated from Late Pleistocene levels at Liang Bua cave, 50 km to the west. The latter artefacts, dated to between 95-74 and 12 kyr ago.sup.8,9, are associated with the remains of a dwarfed descendent of S. florensis, Komodo dragon, rat and a small-bodied hominin species, Homo floresiensis, which had a brain size of about 400 cubic centimetres.sup.10,11. The Mata Menge evidence negates claims that stone artefacts associated with H. floresiensis are so complex that they must have been made by modern humans (Homo sapiens).sup.7., Author(s): Adam Brumm [sup.1] , Fachroel Aziz [sup.2] , Gert D. van den Bergh [sup.3] , Michael J. Morwood [sup.4] , Mark W. Moore [sup.4] , Iwan Kurniawan [sup.2] , [...]

Toolmakers in Queensland Australia used ingenious knapping techniques to produce an implement with a large bulb of percussion and a gouge-shaped cutting edge: the 'gull-wing 'dze'. The author concludes that the tool results from a unique compromise between an inefficient knapping technique and a peculiar--but in this case desirable--phenomenon of fracture mechanics. Keywords: Lithics, Australia, Queensland., Introduction Lithic technologists are sometimes confronted with forms of stone tools which are hard to explain. To give an example from North America, the highly technical means used to flute [...]

The receptor system of the glial-cell-line-derived neurotrophic factor (GDNF) consists of the GDNFR-alpha protein as the ligand-binding factor and the tyrosine kinase receptor Ret as the signaling factor. GDNFR-alpha is a glycosyl-phosphatidylinositol-linked protein and induces tyrosine phosphorylation of Ret. It is expressed on cells that respond to GDNF and has a high binding affinity for GDNF. The similarities in Ret-deficient and GDNF-deficient mice indicate Ret's involvement in GDNF signaling.

Mice homozygous for a null glial-cell-line-derived neurotrophic factor (GDNF) allele exhibit the absence of kidneys, ureters and enteric nervous system (ENS). The mutants show defects in the sympathetic and nodose neurons, and dorsal root ganglion. The basal forebrain, cerebellum, striatum, neocortex, hippocampus, and the dopaminergic, catecholaminergic and noradrenergic neurons are normal. This indicates that GDNF is necessary for the development of ENS, kidney, and sympathetic and sensory neurons. The homozygous mice die within two days of birth while the heterozygous mice are normal in size.

The disruption of a single vascular endothelial growth factor (VEGF) gene in the embryonic stem (ES) cells causes lethality within 11-12 days in a nude mouse model. Defective angiogenesis and blood-island development produces several physiological and pathological abnormalities. This confirms the importance of VEGF in pathological angiogenesis. The ES cells lacking VEGF allele are inactive in tumorigenesis.

A study of mice, deficient in tumor necrosis factor (TNF) receptor, TNF-R2, shows that they have normal cell development although they are resistant to TNF-induced death. The findings prove that a deficiency of TNF-R2 results in a decreased TNF sensitivity although it does not influence the toxic effects of lipopolysaccharide and TNS. The deficiency leads to a reduction in tissue necrosis, which suggests that TNF-R2 affects the necrotic effects of TNF.

The Kimberley region of Western Australia is one of the largest and most diverse rock art provenances in the world, with a complex stylistic sequence spanning at least 16 ka, culminating in the modern art-making of the Wunumbal people. The Gunu Site Complex, in the remote Mitchell River region of the northwest Kimberley, is one of many local expressions of the Kimberley rock art sequence. Here we report excavations at two sites in this complex: Gunu Rock, a sand sheet adjacent to rock art panels; and Gunu Cave, a floor deposit within an extensive rockshelter. Excavations at Gunu Rock provide evidence for two phases of occupation, the first from 7–8 to 2.7 ka, and the second from 1064 cal BP. Excavations at Gunu Rock provide evidence for occupation from the end of the second phase to the recent past. Stone for tools in the early phase were procured from a variety of sources, but quartz crystal reduction dominated the second occupation phase. Small quartz crystals were reduced by freehand percussion to provide small flake tools and blanks for manufacturing small points called nguni by the Wunambal people today. Quartz crystals were prominent in historic ritual practices associated with the Wanjina belief system. Complex methods of making bifacially-thinned and pressure flaked quartzite projectile points emerged after 2.7 ka. Ochre pigments were common in both occupation phases, but evidence for occupation contemporaneous with the putative age of the oldest rock art styles was not discovered in the excavations. Our results show that developing a complete understanding of rock art production and local occupation patterns requires paired excavations inside and outside of the rockshelters that dominate the Kimberley. [ABSTRACT FROM AUTHOR]

Interleukin-8 (IL-8) is a proinflammatory cytokine that specifically attracts and activates human neutrophils. A murine gene with a high degree of homology to the two known human IL-8 receptors was [...]