Results 61 to 70 of about 13,981 (252)

Polar bears observed climbing steep slopes to graze on scurvy grass in Svalbard

Polar Research, 2017
It is well known that polar bears feed on vegetation. Here, I report novel observations of polar bears grazing on polar scurvy grass (Cochlearia groenlandica) at the foot of a large seabird colony on a cliff on Spitsbergen, Svalbard, in the summers of ...
Lech Stempniewicz
doaj   +1 more source

Modular Critical Element Recycling Platform Using a Nanoporous Additively Manufactured Gyroid

Advanced Engineering Materials, EarlyView.
A modular recycling platform integrates 3D‐printed nanoporous gyroid structures to enable efficient critical element recovery. This system utilizes a hierarchical architecture, combining macroscopic channels with polymerization‐induced nanoscale porosity. By systematically tuning structural wall thickness and resin formulation, the platform achieves an
Xiangyu Gao, Keldy Mason, Mert Gülçür, Rachel Paddock‐Lamb, Prince Alvin Fofanah, Zachariah A. Page, Michael Cullinan   +6 more
wiley   +1 more source

Mama Grizzly and the polar bears [PDF]

The EMBO Reports, 2012
Mis-reporting of the science behind climate change has called into question the judgement and integrity of scientists. Howy argues that better communication between scientists and journalists is needed, to restore public confidence in both.
openaire   +2 more sources

Microstructure, Thermal Transport, and Dry‐Sliding Tribology of Powder‐Metallurgy Al7075 Composites Reinforced With Sol–Gel‐Derived ZnO–rGO Hybrid Nanoparticles

Advanced Engineering Materials, EarlyView.
Sol–gel‐derived ZnO–rGO hybrid nanoparticles enable Al7075 powder‐metallurgy composites to achieve concurrent gains in hardness and thermal conductivity while markedly lowering friction and wear. The hybrid architecture couples ZnO‐based load support with rGO‐assisted lamellar sliding and heat spreading, revealing a promising route toward lightweight ...
Bunyamin Aksakal, Cevher Kursat Macit, Merve Ayık, Hakan Tutumlu   +3 more
wiley   +1 more source

Testosterone concentrations in juvenile male polar bears (Ursus maritimus)

Theriogenology Wild
The ex situ polar bear population in the United States is not sustainable. Current management practices include pairing mates at five to six years of age, but there is evidence that wild bears have sired cubs as early as two years old. Timing acquisition
Jessye Wojtusik, Megan Philpott, Elizabeth Donelan, Monica A. Stoops, Terri L. Roth, Erin Curry   +5 more
doaj   +1 more source

Defect Evolution and Mechanical Performance of Fused Filament Fabrication‐Manufactured 17‐4PH Stainless Steel Revealed by X‐Ray Computed Tomography

Advanced Engineering Materials, EarlyView.
X‐ray computed tomography reveals how process‐induced defects evolve from green to sintered states in Fused Filament Fabrication (FFF)‐manufactured 17‐4PH stainless steel. Internal porosity, weakest cross‐sections, and fracture locations show strong correlation with tensile performance, demonstrating the potential of computed tomography (CT)‐based ...
György Ledniczky, Márk Sárközi, Ibolya Zsoldos, Zoltán Weltsch   +3 more
wiley   +1 more source

Design and Analysis of Compression–Torsion Coupling Metamaterials Using the Golden Section Method

Advanced Engineering Materials, EarlyView.
A novel compression–torsion metamaterial is engineered using inclined rods and symmetry breaking. To optimize its torsional performance, the golden section method is employed. The mechanical response of the metamaterial is validated through both numerical analysis and experimental validation.
Amirhossein Hassani, Sara Bagherifard
wiley   +1 more source

The ecological and behavioral significance of short-term food caching in polar bears (Ursus maritimus)

Arctic Science, 2020
The paucity of observations of wild polar bears (Ursus maritimus) caching of food (including hoarding, i.e., burying and remaining with a kill for up to a few days) has led to the conclusion that such behavior does not occur or is negligible in this ...
Ian Stirling, Kristin L. Laidre, Andrew E. Derocher, Rinie Van Meurs   +3 more
doaj   +1 more source

Influence of Scan Strategies in Electron Beam Powder Bed Fusion on Solidification, Microstructure, and High‐Temperature Compressive Properties of γ′‐Strengthened Inconel 738LC

Advanced Engineering Materials, EarlyView.
Experiments and thermophysical simulations were conducted to investigate the electron beam powder bed fusion electron beam (PBF‐EB/M) process for the γ′‐strengthened nickel‐based superalloy Inconel 738LC. The results demonstrate the impact of process‐induced microstructural variations on high‐temperature mechanical behavior, providing a basis for ...
Jan Niklas Petenati, Karthik Kumar Banku, Prasanth Bondi, Ivan Zhirnov, Yangyiwei Yang, Gordon Schmidt, Jürgen Christen, Georg Hasemann, Manja Krüger, Bai‐Xiang Xu, Bilal Gökce, Silja‐Katharina Rittinghaus   +11 more
wiley   +1 more source

Polar Bears

The polar bear (Ursus maritimus) is the largest carnivore on land and the 19 subpopulations roam the territory and ice-covered waters of Canada, Greenland, Svalbard, Russia and Alaska. The 1973 Agreement on the Conservation of Polar Bears was a direct response to the over-hunting of the species.
Fahrenkrug, Leoni, Bastmeijer, Kees
openaire   +2 more sources