Results 31 to 40 of about 464 (129)

The impact of isosmotic conditions on the metabolism and hypoxia tolerance of a reportedly oxyconforming teleost

Journal of Fish Biology, EarlyView.
Abstract Fish must manage the competing demands of ion balance and gas exchange across the gills – a physiological tension known as the osmorespiratory compromise. In dynamic estuarine environments, the osmorespiratory compromise may be exacerbated by variable salinity and periods of hypoxia that demand high respiratory work.
Timothy D. Clark, Luis L. Kuchenmüller, Elizabeth C. Hoots, Maryane Gradito, Jake M. Martin   +4 more
wiley   +1 more source

Além das galáxias brilhantes: a descoberta da matéria escura e o papel de Vera Rubin [PDF]

Revista Brasileira de Ensino de Física
Desde a década de 1930 os cientistas enfrentavam dificuldades para calcular a massa de aglomerados de galáxias a partir da luminosidade, pois os efeitos gravitacionais observados não correspondiam à soma das massas visíveis.
Julia Medeiros, Gabriela Kaiana Ferreira
doaj   +1 more source

Swimming Under the Radar: Trout‐Free Kōaro Populations in Aotearoa Lakes and Tarns Are Rare, Understudied, and Disappearing

New Zealand Journal of Marine and Freshwater Research, Volume 60, Issue 2, June 2026.
Over the last 150 years, most large, easily accessible lakes and tarns in Aotearoa (New Zealand) have experienced trout introductions or incursions, leaving few salmonid‐free reference lakes. Using database information and field surveys, we characterized lake, pond/tarn, and wetland systems found throughout Aotearoa that support populations of kōaro ...
Lauren G. Hitt, Simon D. Stewart, Nixie C. Boddy, Angus R. McIntosh   +3 more
wiley   +1 more source

Two Germans, a Swede, and a Giant kōkopu: The Background to the Earliest Documented Description of a New Zealand Freshwater Fish

New Zealand Journal of Marine and Freshwater Research, Volume 60, Issue 2, June 2026.
Galaxiids are a family of scaleless and mostly small freshwater fish which are distributed across the temperate latitudes of the southern hemisphere. The largest member of this family is the giant kōkopu (Galaxias argenteus), which has the added distinction of being the first New Zealand freshwater fish of any kind to be scientifically described.
James Braund
wiley   +1 more source

Rayos cósmicos ultra-energéticos y lentes magnéticas

Momento, 2000
I discuss the effects associated to the defiection of ultra- high energy cosmic rays by galactic magnetic fields. These are of particular interest for the study and localization of extragalactic sources, which is one of the primary objectives of the ...
Esteban Roulet
doaj  

Matéria Escura no Ensino Médio

Revista Brasileira de Ensino de Física, 2023
Apresentamos uma abordagem do conceito de matéria escura, desenvolvida visando o ensino médio. Evidências da existência de matéria escura são estudadas a partir das curvas de rotação de galáxias, utilizando apenas elementos presentes na grade curricular ...
Samuel Jorge Carvalho Ximenes, Carlos Eduardo Aguiar   +1 more
doaj   +1 more source

Virial theorem and gravitational equilibrium with a cosmological constant

Momento, 2001
Starting from the Newtonian limit of Einstein's equations in the presence of a positive cosmological constant, we obtain a new version of the virial theorem and a condition for gravitational equilibrium. Such a condition takes the form ρ > λρvac, where ρ
Marek Nowakowski, Juan Carlos Sanabria, Alejandro García   +2 more
doaj  

Balancing Harvest and Habitat: A Framework for the Sustainable Management of Diadromous Galaxiids

New Zealand Journal of Marine and Freshwater Research, Volume 60, Issue 1, March 2026.
Managing New Zealand's diadromous Galaxias species and the associated whitebait fishery presents a complex challenge due to species‐specific differences in life‐history strategies, habitat requirements, and population dynamics that underpin responses to anthropogenic and environmental pressures.
Ben R. J. Crichton, Michael J. H. Hickford, Angus R. McIntosh, David R. Schiel, Andrew S. Watson   +4 more
wiley   +1 more source

Commentary: Trends and Tensions in Freshwater and Fisheries Management in Central Otago, New Zealand

New Zealand Journal of Marine and Freshwater Research, Volume 60, Issue 1, March 2026.
Recent resource management planning processes and decisions in Central Otago, New Zealand, illustrate changes in policy direction for freshwater management. These processes and decisions also highlight interactions between, and values associated with, indigenous and introduced sports fish.
Harvey C. Perkins, Niall R. N. Watson
wiley   +1 more source

Perturbações cosmológicas e a taxa de crescimento das flutuações da matéria

Revista Brasileira de Ensino de Física
As estruturas observadas no universo (galáxias, aglomerados e superaglomerados de galáxias) são resultados da instabilidade gravitacional. Esta instabilidade amplifica perturbações, originalmente muito pequenas, até o regime não linear.
R.F. Vom Marttens, F.K. Ribeiro, W. Zimdahl   +2 more
doaj   +1 more source