Results 31 to 40 of about 252 (179)

Chironomid‐based summer temperature reconstruction of the Eemian–Weichselian transition at Lichtenberg, northern Germany

open access: yesBoreas, EarlyView.
Understanding the temperature variability of past interglacial cycles is essential to predict future climates. We present a new summer temperature reconstruction, based on the subfossil chironomid record from a small palaeolake adjacent to the Middle Palaeolithic site of Lichtenberg, northern Germany. The record spans from the Saalian late glacial over
Sonja Rigterink   +10 more
wiley   +1 more source

Rock Breaking Analysis and Process Parameter Optimization of Pneumatic DTH Hammer Bit

open access: yesShiyou jixie, 2022
In order to improve the rock-breaking efficiency and penetration ability of pneumatic DTH hammer in hard strata, based on the theory of nonlinear contact dynamics, the ABAQUS software was used to build a piston-pneumatic DTH hammer bit-rock(granite ...
Wang Shenglin   +5 more
doaj  

Impact Dynamics Prediction of a Rotary-Percussive Ultrasonic Drill With a Free Mass

open access: yesIEEE Access, 2018
The rotary-percussive ultrasonic drill (RPUD) employs vibrations on two sides of a piezoelectric stack to drive a drill tool to achieve simultaneous rotary-percussive motion.
Deen Bai   +5 more
doaj   +1 more source

Towards an ‘absolute’ timing of biostratigraphic and environmental phases from the Saalian late glacial to the Weichselian pleniglacial in central Europe—Insights from a lacustrine succession in Lichtenberg, northern Germany

open access: yesBoreas, EarlyView.
Palynological records are central to the biostratigraphic subdivision of the Late Pleistocene in central Europe. Yet many interglacial and interstadial phases—such as the Eemian, Brörup and Odderade—remain only poorly constrained in time due to limited numerical dating.
Michael Hein   +19 more
wiley   +1 more source

A bifacial paradise—The site of Ochtmissen, Germany, and its lithic assemblage in the context of the last glacial (early MIS 4) in the north‐central European Lowland

open access: yesBoreas, EarlyView.
The Palaeolithic site of Ochtmissen (Lower Saxony, Germany) was excavated in fluvial terrace deposits during the winter of 1993/1994. The current study presents, for the first time, a thorough analysis of the lithic assemblage, encompassing its primary technological and typological characteristics, as well as the type and age of the fluvial deposits ...
Gianpiero Di Maida   +4 more
wiley   +1 more source

Study on ROP Enhancement of Composite Percussive Drilling in Deep Tight Shale

open access: yesXinjiang shiyou tianranqi
To address the challenges of high compressive strength,low drillability,and extended drilling time in the deep tight shale of the Mabei Fengcheng Formation,an experimental study on drilling parameter optimization for axial-torsional coupled percussive ...
MU Zongjie   +5 more
doaj   +1 more source

Stem Cells From Dental Pulp, Periodontal Tissues, and Other Oral Sources: Biological Concepts and Regenerative Potential

open access: yesJournal of Periodontal Research, EarlyView.
A graphical abstract recapping the different sources of dental, periodontal, and other oral‐derived mesenchymal stromal cells (MSCs) and their regenerative mechanisms and potentials. The review's article findings bridge fundamental biological science with translational advances, highlighting the significance of MSCs in craniofacial regenerative ...
Karim M. Fawzy El‐Sayed   +6 more
wiley   +1 more source

Design, test, and verification of in-situ condition preserved coring and analysis system in lunar-based simulation environment

open access: yesInternational Journal of Mining Science and Technology
The lunar surface and its deep layers contain abundant resources and valuable information resources, the exploration and exploitation of which are important for the sustainable development of the human economy and society.
Haichun Hao   +12 more
doaj   +1 more source

Integrating Acoustic Telemetry and Stable Isotope Data Reveals Overlap in Resource Use by Large‐Bodied Fishes in a Temperate Lake

open access: yesEcology of Freshwater Fish, Volume 35, Issue 4, October 2026.
ABSTRACT Temperate lake ecosystems undergo seasonal shifts that disproportionately alter the availability of suitable habitat for fishes of different thermal guilds. While many studies have investigated fish habitat use patterns, few have estimated the degree to which fish species overlap in space across seasons from a three‐dimensional perspective ...
Ian A. Richter   +3 more
wiley   +1 more source

Impacted Bones: Can Extant Primates Help Identify Tool Use in Early Hominins?

open access: yesEvolutionary Anthropology: Issues, News, and Reviews, Volume 35, Issue 3, September 2026.
ABSTRACT Despite recent advances pushing back the earliest record of tool use, how and when it first emerged in hominins, and the extent to which it featured amongst the numerous co‐existing species, remain critical questions in paleoanthropology. In addition to analyzing fossils and lithic toolkits, novel strides in understanding this might be made by
Rachel M. Hurwitz   +3 more
wiley   +1 more source

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