Results 41 to 50 of about 4,776 (172)

Environmental DNA as a Detection and Quantitative Tool for Brown Bullhead Catfish (Ameiurus nebulosus): A Comparison With Conventional Netting

Environmental DNA, Volume 8, Issue 4, July‐August 2026.
Multiple environmental DNA (eDNA) methods were compared with each other and with fyke netting for detecting invasive brown bullhead catfish. eDNA sampling combined with catfish‐specific metabarcoding provides sensitive detection and effectively complements traditional netting for biosecurity.
Nicola Rose Pyper, Shaun Wilkinson, Angela McGaughran   +2 more
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  

Distribution, identification and biology of freshwater fishes in south-western Australia [PDF]

, 1998
A total of 410 sites in the major watersheds in the south-western corner of Australia, bounded by Bunbury in the north-west and just east of Albany in the south-east, were sampled for fish.
Morgan, D.L., Potter, I.C., Gill, H.S.
core  

Impacts of climate change on temperature and dissolved oxygen in an oligotrophic deep lake

Limnology and Oceanography, Volume 71, Issue 7, July 2026.
Abstract Climate change has significant effects on freshwater ecosystems, including lakes, influencing key water quality indicators such as water temperature and dissolved oxygen concentrations (DO). This study uses a 3D hydrodynamic model (AEM3D) coupled with a simple biogeochemical module (iWQ) alongside observations to examine historical changes in ...
Aidin Jabbari, Piet Verburg, David Plew, Simon D. Stewart, Mat Allan, Christian Zammit   +5 more
wiley   +1 more source

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

Potential Impacts of Low Flows on Fish Foodscapes and Production in a Braided River

River Research and Applications, Volume 42, Issue 6, Page 1366-1382, July 2026.
ABSTRACT Changes in river discharge affect the physical composition and connectivity of habitats which, in turn, may shape the spatial distribution of fish food abundance, accessibility and quality—the ‘foodscape’—of river ecosystems. However, the influence of river flows on fish foodscapes has received very little attention from scientists. We studied
Rick J. Stoffels, Richard S. A. White, Gergely T. Torok, Richard J. Measures, Kristy L. Hogsden, Alex F. Rose, Paul W. Lambert, Jaret P. Bilewitch, S. Elizabeth Graham, Lisa Smith, Amber R. Brooks, Brian J. Smith   +11 more
wiley   +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  

Espectroscopia de Hidrocarburos Aromáticos Policíclos en Núcleos Activos de Galaxias y Galaxias con actividad estelar [PDF]

, 2012
En esta contribución se presenta el comportamiento de las emisiones en la región espectral del infrarrojo cercano y medio (NIR-MIR) de los Hidrocarburos Aromáticos Policíclicos (PAHs), provenientes de distintos tipos de objetos extragalácticos: Núcleos ...
Ramos Padilla, Andrés Felipe, Higuera Garzón, Mario Armando   +1 more
core  

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

Galaxias Activas: alimentando al monstruo [PDF]

, 2015
Uno de los resultados más relevantes de la astrofísica en los últimos años es que muchas galaxias (incluida nuestra propia Vía Láctea) contienen un gran agujero negro de gran masa en el centro. Cuando uno de estos agujeros negros despierta de su letargo,
Villar, Montserrat
core