Results 11 to 20 of about 288,938 (268)
The Electronic Journal of Combinatorics, 2015 Let $2 \leq k_1 < k_2 < \ldots < k_t $, $3 \leq g_1 < g_2 < \ldots < g_s < N$ be integer parameters. A $(k_1,k_2,\ldots,k_t;g_1,g_2,\dots,g_s;N)$-graph is a graph that contains vertices of degrees $k_1,k_2,\ldots,k_t$ but no other degrees and cycles of lengths $g_1,g_2,\dots,g_s$ but no other cycles of length $< N$.
Boben, Marko +2 more
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Discrete Mathematics & Theoretical Computer Science, 2023 Mixed graphs have both directed and undirected edges. A mixed cage is a regular mixed graph of given girth with minimum possible order. In this paper mixed cages are studied. Upper bounds are obtained by general construction methods and computer searches.
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Deglacial bottom water warming intensified Arctic methane seepage in the NW Barents Sea
Communications Earth & Environment, 2021 Phases of high bottom water temperature in the northwestern Barents Sea caused repeated destabilization of methane gas hydrates since the last glacial, according to a foraminifera Mg/Ca bottom water temperature record and hydrate stability ...
Naima El bani Altuna +5 more
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European Spine Journal, 2000 Restoring a stable anterior column is essential to achieve normal spinal biomechanics. A variety of mechanical spacers have been developed and advocated for both anterior and posterior approaches. The ability to radiographically assess the "biology" of bone incorporation in these mechanical (metal) spacers is an inherent limitation.
M E, Janssen +3 more
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High-resolution underwater laser spectrometer sensing provides new insights into methane distribution at an Arctic seepage site [PDF]
Ocean Science, 2019 Methane (CH4) in marine sediments has the potential to contribute to changes in the ocean and climate system. Physical and biochemical processes that are difficult to quantify with current standard methods such as acoustic surveys and discrete sampling ...
P. Jansson +6 more
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Geophysical and geochemical controls on the megafaunal community of a high Arctic cold seep [PDF]
Biogeosciences, 2018 Cold-seep megafaunal communities around gas hydrate mounds (pingos) in the western Barents Sea (76° N, 16° E, ∼ 400 m depth) were investigated with high-resolution, geographically referenced images acquired with an ROV and towed camera.
A. Sen +10 more
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Nature Chemistry, 2009 A 'Russian doll' endohedral fullerene has been made, comprising a carbon dimer within a scandium tetrahedron, all encased by a C80 cage.
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Ice-sheet-driven methane storage and release in the Arctic
Nature Communications, 2016 Methane release across the Arctic continental shelf has been attributed to modern dissociation of gas hydrate, accelerated by ocean warming. Here, the authors show that thermogenic methane was stored as subglacial gas hydrate during the last glaciation ...
Alexey Portnov +3 more
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Graphs and Combinatorics, 2019 We introduce the notion of a $[z, r; g]$-mixed cage. A $[z, r; g]$-mixed cage is a mixed graph $G$, $z$-regular by arcs, $r$-regular by edges, with girth $g$ and minimum order. In this paper we prove the existence of $[z, r ;g]$-mixed cages and exhibit families of mixed cages for some specific values.
Gabriela Araujo-Pardo +2 more
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Shallow carbon storage in ancient buried thermokarst in the South Kara Sea
Scientific Reports, 2018 Geophysical data from the South Kara Sea reveal U-shaped erosional structures buried beneath the 50–250 m deep seafloor of the continental shelf across an area of ~32 000 km2.
Alexey Portnov +6 more
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