scholarly journals A 1.4-million-year-old bone handaxe from Konso, Ethiopia, shows advanced tool technology in the early Acheulean

2020 ◽  
Vol 117 (31) ◽  
pp. 18393-18400 ◽  
Author(s):  
Katsuhiro Sano ◽  
Yonas Beyene ◽  
Shigehiro Katoh ◽  
Daisuke Koyabu ◽  
Hideki Endo ◽  
...  
Keyword(s):  
Early Pleistocene ◽  
Southern Ethiopia ◽  
Bone Tools ◽  
The Past ◽  
Lithic Assemblages ◽  
Use Wear ◽  
Core Reduction ◽  
Active Research ◽  
Tool Technology ◽  
Advanced Tool

In the past decade, the early Acheulean before 1 Mya has been a focus of active research. Acheulean lithic assemblages have been shown to extend back to ∼1.75 Mya, and considerable advances in core reduction technologies are seen by 1.5 to 1.4 Mya. Here we report a bifacially flaked bone fragment (maximum dimension ∼13 cm) of a hippopotamus femur from the ∼1.4 Mya sediments of the Konso Formation in southern Ethiopia. The large number of flake scars and their distribution pattern, together with the high frequency of cone fractures, indicate anthropogenic flaking into handaxe-like form. Use-wear analyses show quasi-continuous alternate microflake scars, wear polish, edge rounding, and striae patches along an ∼5-cm-long edge toward the handaxe tip. The striae run predominantly oblique to the edge, with some perpendicular, on both the cortical and inner faces. The combined evidence is consistent with the use of this bone artifact in longitudinal motions, such as in cutting and/or sawing. This bone handaxe is the oldest known extensively flaked example from the Early Pleistocene. Despite scarcity of well-shaped bone tools, its presence at Konso shows that sophisticated flaking was practiced by ∼1.4 Mya, not only on a range of lithic materials, but also occasionally on bone, thus expanding the documented technological repertoire of African Early PleistoceneHomo.

scholarly journals Recent Advances in bis-Chalcone-Based Photoinitiators of Polymerization: From Mechanistic Investigations to Applications

Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3192
Author(s):  
Nicolas Giacoletto ◽  
Frédéric Dumur
Keyword(s):  
Free Radical ◽  
Radical Polymerization ◽  
Cationic Polymerization ◽  
Free Radical Polymerization ◽  
Research Field ◽  
4D Printing ◽  
Unique Structure ◽  
The Past ◽  
Mechanistic Investigations ◽  
Active Research

Over the past several decades, photopolymerization has become an active research field, and the ongoing efforts to develop new photoinitiating systems are supported by the different applications in which this polymerization technique is involved—including dentistry, 3D and 4D printing, adhesives, and laser writing. In the search for new structures, bis-chalcones that combine two chalcones’ moieties within a unique structure were determined as being promising photosensitizers to initiate both the free-radical polymerization of acrylates and the cationic polymerization of epoxides. In this review, an overview of the different bis-chalcones reported to date is provided. Parallel to the mechanistic investigations aiming at elucidating the polymerization mechanisms, bis-chalcones-based photoinitiating systems were used for different applications, which are detailed in this review.

Research trends in sociological studies on social security and welfare

2021 ◽  
pp. 026858092110053
Author(s):  
Koichi Hiraoka
Keyword(s):  
Social Security ◽  
Research Trends ◽  
Important Research ◽  
Research Results ◽  
The Past ◽  
Active Research ◽  
The Many ◽  
Sociological Studies ◽  
Broad Overview

This article reviews the research trends in welfare sociology (sociological studies on social security and welfare), one of the many subfields of active research in sociology in Japan. For this purpose, several research streams formed from the 1970s to the 2000s are described, and some of the most important research results produced within these in the past two decades are introduced. In the latter part of this article, a broad overview of the research trends in Japanese welfare sociology is attempted by focusing on the contents of the journal published by the Japan Welfare Sociology Association (JWSA).

Epithelial-Stromal Interactions in Pancreatic Cancer

2019 ◽  
Vol 81 (1) ◽  
pp. 211-233 ◽  
Author(s):  
Yaqing Zhang ◽  
Howard C. Crawford ◽  
Marina Pasca di Magliano
Keyword(s):  
Pancreatic Cancer ◽  
Extracellular Matrix ◽  
Immune Cells ◽  
Lymphatic Vessels ◽  
Cancer Microenvironment ◽  
Cancer Stroma ◽  
The Past ◽  
Overwhelming Evidence ◽  
Cancer Initiation ◽  
Active Research

Pancreatic cancer is characterized by an extensive fibroinflammatory reaction that includes immune cells, fibroblasts, extracellular matrix, vascular and lymphatic vessels, and nerves. Overwhelming evidence indicates that the pancreatic cancer microenvironment regulates cancer initiation, progression, and maintenance. Pancreatic cancer treatment has progressed little over the past several decades, and the prognosis remains one of the worst for any cancer. The contribution of the microenvironment to carcinogenesis is a key area of research, offering new potential targets for treating the disease. Here, we explore the composition of the pancreatic cancer stroma, discuss the network of interactions between different components, and describe recent attempts to target the stroma therapeutically. We also discuss current areas of active research related to the tumor microenvironment.

scholarly journals A 115,000-year-old expedient bone technology at Lingjing, Henan, China

2020 ◽  
Author(s):  
Luc Doyon ◽  
Li Zhanyang ◽  
Wang Hua ◽  
Lila Geis ◽  
Francesco d'Errico
Keyword(s):  
Long Bone ◽  
Faunal Remains ◽  
Faunal Assemblage ◽  
Bone Tools ◽  
Qualitative And Quantitative ◽  
Lithic Assemblages ◽  
Technological Potential ◽  
Bone Fragments ◽  
Anthropogenic Processes ◽  
Stone Knapping

Activities attested since at least 2.6 Myr, such as stone knapping, marrow extraction, and woodworking may have allowed early hominins to recognize the technological potential of discarded skeletal remains and equipped them with a transferable skillset fit for the marginal modification and utilization of bone flakes. Identifying precisely when and where expedient bone tools were used in prehistory nonetheless remains a challenging task owing to the multiple natural and anthropogenic processes that can mimic deliberately knapped bones. Here, we compare a large sample of the faunal remains from Lingjing, a 115 ka-old site from China which has yielded important hominin remains and rich faunal and lithic assemblages, with bone fragments produced by experimentally fracturing Equus caballus long bones. Our results provide a set of qualitative and quantitative criteria that can help zooarchaeologists and bone technologists distinguish faunal remains with intentional flake removal scars from those resulting from carcass processing activities. Experimental data shows marrow extraction seldom generates diaphyseal fragments bearing more than six flake scars arranged contiguously or in interspersed series. Long bone fragments presenting such characteristics can, therefore, be interpreted as being purposefully knapped to be used as expediency tools. The identification, based on the above experimental criteria, of 56 bone tools in the Lingjing faunal assemblage is consistent with the smaller size of the lithics found in the same layer. The continuity gradient observed in the size of lithics and knapped bones suggest the latter were used for tasks in which the former were less or not effective.

scholarly journals Elephant bones for the Middle Pleistocene toolmaker

PLoS ONE ◽  
2021 ◽  
Vol 16 (8) ◽  
pp. e0256090
Author(s):  
Paola Villa ◽  
Giovanni Boschian ◽  
Luca Pollarolo ◽  
Daniela Saccà ◽  
Fabrizio Marra ◽  
...  
Keyword(s):  
Upper Paleolithic ◽  
Raw Material ◽  
General Idea ◽  
Early Pleistocene ◽  
Stone Tool ◽  
Middle Pleistocene ◽  
Medium Size ◽  
Bone Tools ◽  
Lithic Industry ◽  
Taphonomic Analysis

The use of bone as raw material for implements is documented since the Early Pleistocene. Throughout the Early and Middle Pleistocene bone tool shaping was done by percussion flaking, the same technique used for knapping stone artifacts, although bone shaping was rare compared to stone tool flaking. Until recently the generally accepted idea was that early bone technology was essentially immediate and expedient, based on single-stage operations, using available bone fragments of large to medium size animals. Only Upper Paleolithic bone tools would involve several stages of manufacture with clear evidence of primary flaking or breaking of bone to produce the kind of fragments required for different kinds of tools. Our technological and taphonomic analysis of the bone assemblage of Castel di Guido, a Middle Pleistocene site in Italy, now dated by 40Ar/39Ar to about 400 ka, shows that this general idea is inexact. In spite of the fact that the number of bone bifaces at the site had been largely overestimated in previous publications, the number of verified, human-made bone tools is 98. This is the highest number of flaked bone tools made by pre-modern hominids published so far. Moreover the Castel di Guido bone assemblage is characterized by systematic production of standardized blanks (elephant diaphysis fragments) and clear diversity of tool types. Bone smoothers and intermediate pieces prove that some features of Aurignacian technology have roots that go beyond the late Mousterian, back to the Middle Pleistocene. Clearly the Castel di Guido hominids had done the first step in the process of increasing complexity of bone technology. We discuss the reasons why this innovation was not developed. The analysis of the lithic industry is done for comparison with the bone industry.

scholarly journals ELIXIR and Toxicology: a community in development

F1000Research ◽  
2021 ◽  
Vol 10 ◽  
pp. 1129
Author(s):  
Marvin Martens ◽  
Rob Stierum ◽  
Emma L. Schymanski ◽  
Chris T. Evelo ◽  
Reza Aalizadeh ◽  
...  
Keyword(s):  
Life Science ◽  
High Gain ◽  
Research Field ◽  
Predictive Toxicology ◽  
Chemical Risk Assessment ◽  
The Past ◽  
Government Involvement ◽  
Active Research ◽  
New Community ◽  
The Eu

Toxicology has been an active research field for many decades, with academic, industrial and government involvement. Modern omics and computational approaches are changing the field, from merely disease-specific observational models into target-specific predictive models. Traditionally, toxicology has strong links with other fields such as biology, chemistry, pharmacology and medicine. With the rise of synthetic and new engineered materials, alongside ongoing prioritisation needs in chemical risk assessment for existing chemicals, early predictive evaluations are becoming of utmost importance to both scientific and regulatory purposes. ELIXIR is an intergovernmental organisation that brings together life science resources from across Europe. To coordinate the linkage of various life science efforts around modern predictive toxicology, the establishment of a new ELIXIR Community is seen as instrumental. In the past few years, joint efforts, building on incidental overlap, have been piloted in the context of ELIXIR. For example, the EU-ToxRisk, diXa, HeCaToS, transQST, and the nanotoxicology community have worked with the ELIXIR TeSS, Bioschemas, and Compute Platforms and activities. In 2018, a core group of interested parties wrote a proposal, outlining a sketch of what this new ELIXIR Toxicology Community would look like. A recent workshop (held September 30th to October 1st, 2020) extended this into an ELIXIR Toxicology roadmap and a shortlist of limited investment-high gain collaborations to give body to this new community. This Whitepaper outlines the results of these efforts and defines our vision of the ELIXIR Toxicology Community and how it complements other ELIXIR activities.

Inference of Diets of Early Hominins from Primate Molar Form and Microwear

2019 ◽  
Vol 98 (4) ◽  
pp. 398-405 ◽  
Author(s):  
P.S. Ungar
Keyword(s):  
Food Preferences ◽  
Tooth Wear ◽  
Early Pleistocene ◽  
Dental Microwear ◽  
Dietary Specialization ◽  
The Past ◽  
Early Homo ◽  
Occlusal Surfaces ◽  
Adaptive Nature ◽  
Fossil Hominin

Paleontologists use fossil teeth to reconstruct the diets of early hominins and other extinct species. Some evidence is adaptive: nature selects for tooth size, shape, and structure best suited to specific food types. Other evidence includes traces left by actual foods eaten, such as microscopic tooth wear. This critical review considers how molars work, how they are used, and how occlusal topography and dental microwear can be used to infer diet and food preferences in the past, particularly for hominins of the Pliocene and early Pleistocene. Understanding that cheek teeth function as guides for chewing and tools for fracturing allows us to characterize aspects of occlusal form that reflect mechanical properties of foods to which a species is adapted. Living primates that often eat leaves, for example, have longer crests and more sloping occlusal surfaces than those that prefer hard foods. Studies of feeding ecology have shown, however, that tooth shape does not always correspond to preferred food items. It often follows mechanically challenging foods whether eaten often or rarely. Other lines of evidence that reflect actual tooth use are required to work out food preferences. Microwear textures, for example, reflect foods eaten by individuals in the past such that hard seeds and bone tend to leave complex, pitted surface textures, whereas tough leaves and meat more often leave anisotropic ones covered in long, parallel scratches. The study of fossil hominin molars shows how these various attributes are combined to infer diet and food preference in the past. A trend in occlusal morphology suggests decreased dietary specialization from Australopithecus to early Homo, and increasing dispersion in microwear complexity values is consistent with this. On the other hand, occlusal morphology may suggest dietary specialization in Paranthropus, although different species of this genus have different microwear texture patterns despite similar craniodental adaptations.

scholarly journals New agents on the horizon in hepatocellular carcinoma

2012 ◽  
Vol 5 (1) ◽  
pp. 41-50 ◽  
Author(s):  
Andrew X. Zhu
Keyword(s):  
Hepatocellular Carcinoma ◽  
Phase Iii ◽  
Current Status ◽  
Advanced Hepatocellular Carcinoma ◽  
Targeted Agents ◽  
New Agents ◽  
The Past ◽  
Early Evidence ◽  
Molecularly Targeted Agents ◽  
Active Research

Despite the successful approval and extensive application of sorafenib, the prognosis for patients with advanced hepatocellular carcinoma (HCC) remains poor. Fortunately, there have been renewed and continued interests and active research in developing other molecularly targeted agents in HCC during the past few years. While there is early evidence of antitumor activity of several agents in phase I/II studies, phase III efforts with a few targeted agents have failed, highlighting the challenges of new drug development in HCC. This review summarizes the current status of other molecularly targeted agents under development in advanced HCC.

The Olduvai buffaloPelorovisand the origin ofBos

2007 ◽  
Vol 68 (2) ◽  
pp. 220-226 ◽  
Author(s):  
Bienvenido Martínez-Navarro ◽  
Juan Antonio Pérez-Claros ◽  
Maria Rita Palombo ◽  
Lorenzo Rook ◽  
Paul Palmqvist
Keyword(s):  
Western Europe ◽  
Sensu Stricto ◽  
Early Pleistocene ◽  
Middle Pleistocene ◽  
Morphometric Study ◽  
Large Size ◽  
Morphological Differences ◽  
Mammal Assemblages ◽  
Tool Technology ◽  
Different Origin

AbstractThe origin of the genusBosis a debated issue. From ∼ 0.5 Ma until historic times, the genus is well known in the Eurasian large mammal assemblages, where it is represented byBos primigenius. This species has a highly derived cranial anatomy that shows important morphological differences from other Plio-Pleistocene Eurasian genera of the tribe Bovini such asLeptobos,Bison,Proamphibos-Hemibos, andBubalus. The oldest clear evidence ofBosis the skull fragment ASB-198-1 from the middle Pleistocene (∼ 0.6–0.8 Ma) site of Asbole (Lower Awash Valley, Ethiopia). The first appearance ofBosin Europe is at the site of Venosa-Notarchirico, Italy (∼ 0.5–0.6 Ma). Although the origin ofBoshas traditionally been connected withLeptobosandBison, after a detailed anatomical and morphometric study we propose here a different origin, connecting the middle Pleistocene Eurasian forms ofB. primigeniuswith the African Late Pliocene and early Pleistocene large size member of the tribe BoviniPelorovis sensu stricto. The dispersal of theBoslineage in Western Europe during middle Pleistocene times seems to coincide with the arrival of the Acheulean tool technology in this continent.

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