Results 91 to 100 of about 22,151 (252)

Case Studies of Bear Cub Development Under Unique Rearing Conditions [PDF]

Animal Behavior and Cognition
Zoo-based polar bear (Ursus maritimus) literature is heavily biased towards reproduction and neonate development, or the behavioral management of adult individuals, often excluding the critical juvenile developmental period between den emergence and ...
Kylen N. Gartland, Grace Fuller
doaj   +1 more source

Direct Metal Deposition of Graphene–Ti28Nb35.4Zr Matrix Composites With Enhanced Mechanical, Corrosion, and Biocompatibility Properties for Bone Implants

Advanced Engineering Materials, EarlyView.
Graphene nanoplatelet (0.1 wt.%) reinforcement significantly enhances the performance of β Ti‐28Nb‐35.4Zr alloy. Grain refinement, reduced water contact angle, and improved surface characteristics promote osteoblast adhesion and complete surface coverage after 7 days.
Khurram Munir, Jixing Lin, Yuncang Li, Li Zhu, Paul F. A. Wright, Cuie Wen   +5 more
wiley   +1 more source

Nondestructive Testing of Welded Composite Metal Foams

Advanced Engineering Materials, EarlyView.
X‐ray computed tomography (CT) is used to evaluate welded steel–steel composite metal foam (CMF) joints of two density classes. It reports variation in postweld spatial void distribution and correlates it to weld‐induced changes, mechanical performance, and failure within welded CMF panels.
Chinmaya Prerana Inguva, Aman Kaushik, Afsaneh Rabiei   +2 more
wiley   +1 more source

Stable isotope food-web analysis and mercury biomagnification in polar bears ( Ursus maritimus ) [PDF]

, 2009
Mercury (Hg) biomagnification occurs in many ecosystems, resulting in a greater potential for toxicological effects in higher-level trophic feeders. However, Hg transport pathways through different food-web channels are not well known, particularly in ...
Chamberlain, C. Page, Michael Hren, Horton, Travis W., Zhouqing Xie, Hren, Michael, Travis W. Horton, Blum, Joel D., Xie, Zhouqing, Joel D. Blum, Blum, Joel D   +9 more
core   +1 more source

Encyclopedia of 2D β′‐In2Se3 Growth Using Chemical Vapor Deposition: The Effects of Synthesis Parameters Onto Material Quality

Advanced Engineering Materials, EarlyView.
A distinct semi‐confined inner‐tube chemical vapor deposition geometry enables reproducible, large‐area growth of phase‐pure 2D β′‐In2Se3 from InI + Se precursors. Engineering local vapor transport and optimizing precursor delivery and temperature–time conditions yield uniform continuous films.
Dasun P. W. Guruge, P. Sanju S. Panawala, Joseph F. S. Fernando, Zhenhuan Chen, Chao Zhang, Dong‐Chen Qi, Liangzhi Kou, Konstantin L. Firestein, Dmitri V. Golberg   +8 more
wiley   +1 more source

Ancestral polymorphisms and sex-biased migration shaped the demographic history of brown bears and polar bears.

PLoS ONE, 2013
Recent studies have reported discordant gene trees in the evolution of brown bears and polar bears. Genealogical histories are different among independent nuclear loci and between biparentally inherited autosomal DNA (aDNA) and matrilineal mitochondrial ...
Shigeki Nakagome, Shuhei Mano, Masami Hasegawa   +2 more
doaj   +1 more source

Influence of Surface Finish on the Tribological Performance of AlTiBN Coatings Deposited on Forming Tools

Advanced Engineering Materials, EarlyView.
Aluminum and nitride coatings are used in industry because they are hard, resist wear, and protect against oxidation. Adding boron can improve friction behavior and other properties. This study tests coatings on surfaces with different finishes. Results show smoother surfaces perform better, while rough ones wear faster, although coatings can reduce ...
Adrián Claver, Iker Alfonso, Eneko Barba, Javier León, José Antonio García, Iñaki Zalakain, Iván Fernández Martínez, Arley García‐Carrero, Christian Almeyda, Daniel Salcedo   +9 more
wiley   +1 more source

Low Cycle Repetitive Loading of Ti‐6Al‐4V‐Epoxy Composite Lattice Structures for Enhanced Energy Dissipation and Damage Tolerance

Advanced Engineering Materials, EarlyView.
Composite Ti–6Al–4V–epoxy lattice structures are additively manufactured and epoxy infiltrated for cyclic loading. At low lattice volume fractions, hybridization produces synergistic gains in stiffness and energy dissipation. At higher volume fractions, synergy diminishes, although composites still exceed metallic lattices in specific energy ...
Joey Tallon, Jordan Noronha, Justin Dirrenberger, Andrey Molotnikov   +3 more
wiley   +1 more source

Climate change and the increasing impact of polar bears on bird populations

Frontiers in Ecology and Evolution, 2015
The Arctic is becoming warmer at a high rate, and contractions in the extent of sea ice are currently changing the habitats of marine top-predators dependent on ice. Polar bears (Ursus maritimus) depend on sea ice for hunting seals.
Jouke eProp, Jon eAars, Bård-Jørgen eBårdsen, Sveinn Are eHanssen, Claus eBech, Sophie eBourgeon, Jimmy ede Fouw, Geir Wing eGabrielsen, Johannes eLang, Johannes eLang, Elin eNoreen, Thomas eOudman, Benoit eSittler, Benoit eSittler, Lech eStempniewicz, Ingunn eTombre, Eva eWolters, Børge eMoe   +17 more
doaj   +1 more source

From Shear to Sound: Mechanics–Acoustics Mapping of TPMS Lattices

Advanced Engineering Materials, EarlyView.
Triply periodic minimal surface (TPMS) lattices are mapped across mechanical and acoustic performance, revealing that descriptors validated in compression fail under shear. First‐time comparison with trusses included. A transition from porous to resonance‐driven absorption emerges at 25% density.
Lucía Doyle, María Ángeles Navacerrada, Johan Christensen, Carlos González   +3 more
wiley   +1 more source