Results 71 to 80 of about 29,496 (263)

Thermophilic Sulfate Reduction in Hydrothermal Sediment of Lake Tanganyika, East Africa [PDF]

open access: yes, 1994
In environments with temperatures above 60 degrees C, thermophilic prokaryotes are the only metabolically active life-forms. By using the (SO42-)-S-35 tracer technique, we studied the activity of sulfate-reducing microorganisms (SRM) in hot sediment from
Elsgaard, L.   +3 more
core   +1 more source

The Origin of Life: Models and Data. [PDF]

open access: yes, 2017
A general framework for conventional models of the origin of life (OOL) is the specification of a 'privileged function.' A privileged function is an extant biological function that is excised from its biological context, elevated in importance over other
Lanier, Kathryn A, Williams, Loren Dean
core   +1 more source

Prebiotic aqueous reactions catalyzed by native nickel without hydrogen

open access: yesThe FEBS Journal, EarlyView.
Serpentinizing (H2‐producing) hydrothermal vents are candidate environments for metabolic origin. They generate highly reducing conditions that convert CO2 to formate and methane in abiotic reactions resembling reactions of the acetyl‐CoA pathway of CO2 fixation. They also contain natural catalysts. Native nickel (Ni0), like Fe0, Co0, and their alloys,
Carolina Garcia Garcia   +2 more
wiley   +1 more source

Primordial RNA Replication and Applications in PCR Technology [PDF]

open access: yes, 2013
The emergence of self-replication and information transmission in life's origin remains unexplained despite extensive research on the topic. A hypothesis explaining the transition from a simple organic world to a complex RNA world is offered here based ...
Palasek, Stan
core  

Rifting under steam – how rift magmatism triggers methane venting from sedimentary basins [PDF]

open access: yes, 2016
During opening of a new ocean magma intrudes into the surrounding sedimentary basins. Heat provided by the intrusions matures the host rock creating metamorphic aureoles potentially releasing large amounts of hydrocarbons.
Behrendt, Ruth   +23 more
core   +1 more source

The Role of Oxidative Stress in Periodontitis

open access: yesJournal of Periodontal Research, EarlyView.
Oxidative stress is involved in multiple chemical reactions that take place in different intracellular organelles: mitochondria, rough endoplasmic reticulum, peroxisomes, autophagy, and aging, and can be influenced by exogenous factors: nutrition, physical activity, psychological status, environmental conditions, microbiome, and drugs.
Pedro Bullon   +3 more
wiley   +1 more source

Understanding marine biodiversity patterns and drivers: The fall of Icarus

open access: yesMarine Ecology, EarlyView.
Abstract Biodiversity patterns are fundamental in our understanding of the distribution of life, ecosystem function, and conservation. In this concept analysis, A survey of the existing knowledge on marine biodiversity patterns and drivers across latitudes, longitudes, and depths indicates that none of the postulated patterns represent a rule.
Roberto Danovaro
wiley   +1 more source

Dispersion and Intersection of Hydrothermal Plumes in the Manus Back-Arc Basin, Western Pacific

open access: yesGeofluids, 2020
The composition of hydrothermal plumes reflects the physical and chemical characteristics of seafloor hydrothermal fluids, which in turn reflects the host rock and subseafloor reaction conditions as well as the water column processes that act to alter ...
Zhigang Zeng   +7 more
doaj   +1 more source

Vision in hydrothermal vent shrimp

open access: yesPhilosophical Transactions of the Royal Society of London. Series B: Biological Sciences, 2000
Bresiliid shrimp from hydrothermal vents on the Mid–Atlantic Ridge have non–imaging eyes adapted for photodetection in light environments of very low intensity. Comparison of retinal structures between both vent shrimp and surface–dwelling shrimp with imaging eyes, and between juvenile and adult vent shrimp, suggests that vent shrimp have evolved from ...
openaire   +3 more sources

Search for impact ejecta at the Paleocene–Eocene boundary

open access: yesMeteoritics &Planetary Science, EarlyView.
Abstract Almost 10 years have passed since microtektites and microkrystites were reported for the Paleocene–Eocene (P–E) boundary in drill cores and outcrop in New Jersey and in ODP Hole 1051B in the western North Atlantic. The glassy spherules were interpreted to reflect an impact trigger for the Paleocene–Eocene Thermal Maximum (PETM).
Birger Schmitz   +6 more
wiley   +1 more source

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