scholarly journals Dead Reefs Keep Calcifying but Only by Day

Eos ◽  
2019 ◽  
Vol 100 ◽  
Author(s):  
Jerimiah Oetting
Keyword(s):  
Measurement Technique ◽  
Dual Role ◽  
New Mineral ◽  
Turf Algae ◽  
Mineral Material

A new measurement technique has revealed that turf algae communities colonizing dead reefs have a dual role, adding new mineral material to the reefs during the day and taking it away at night.

TEM/AEM characterization of fine-grained clay minerals in very-low-grade rocks: Evaluation of contamination by empa involving celadonite family minerals

1996 ◽  
Vol 54 ◽  
pp. 694-695
Author(s):  
Gejing Li ◽  
D. R. Peacor ◽  
D. S. Coombs ◽  
Y. Kawachi
Keyword(s):  
Electron Microscopy ◽  
Volcanic Rocks ◽  
Analytical Electron Microscopy ◽  
Metamorphic Rocks ◽  
New Mineral ◽  
Chemical Compositions ◽  
Low Grade ◽  
Fine Grained ◽  
Depth Analysis ◽  
Mineral Aggregates

Recent advances in transmission electron microscopy (TEM) and analytical electron microscopy (AEM) have led to many new insights into the structural and chemical characteristics of very finegrained, optically homogeneous mineral aggregates in sedimentary and very low-grade metamorphic rocks. Chemical compositions obtained by electron microprobe analysis (EMPA) on such materials have been shown by TEM/AEM to result from beam overlap on contaminant phases on a scale below resolution of EMPA, which in turn can lead to errors in interpretation and determination of formation conditions. Here we present an in-depth analysis of the relation between AEM and EMPA data, which leads also to the definition of new mineral phases, and demonstrate the resolution power of AEM relative to EMPA in investigations of very fine-grained mineral aggregates in sedimentary and very low-grade metamorphic rocks.Celadonite, having end-member composition KMgFe3+Si4O10(OH)2, and with minor substitution of Fe2+ for Mg and Al for Fe3+ on octahedral sites, is a fine-grained mica widespread in volcanic rocks and volcaniclastic sediments which have undergone low-temperature alteration in the oceanic crust and in burial metamorphic sequences.

Dual role of B7 costimulation in obesity-related non-alcoholic steatohepatitis (NASH) and metabolic dysregulation

2014 ◽  
Vol 122 (03) ◽  
Author(s):  
A Chatzigeorgiou ◽  
R Garcia-Martin ◽  
KJ Chung ◽  
I Alexaki ◽  
A Klotzsche-von Ameln ◽  
...  
Keyword(s):  
Dual Role ◽  
Alcoholic Steatohepatitis ◽  
Metabolic Dysregulation

A dual role of the N-terminal FQQI motif in GLUT4 trafficking

2008 ◽  
Vol 3 (S 1) ◽  
Author(s):  
U Bernhardt ◽  
HG Joost ◽  
H Al-Hasani
Keyword(s):  
Dual Role

Habitat fragmentation causes collapse of kelp recruitment

2020 ◽  
Vol 648 ◽  
pp. 111-123
Author(s):  
C Layton ◽  
MJ Cameron ◽  
M Tatsumi ◽  
V Shelamoff ◽  
JT Wright ◽  
...  
Keyword(s):  
Habitat Fragmentation ◽  
Patch Size ◽  
Life Stage ◽  
Extended Period ◽  
Anthropogenic Disturbances ◽  
Anthropogenic Sources ◽  
Kelp Forests ◽  
Natural Disturbances ◽  
Short Term ◽  
Turf Algae

Kelp forests in many regions are experiencing disturbance from anthropogenic sources such as ocean warming, pollution, and overgrazing. Unlike natural disturbances such as storms, anthropogenic disturbances often manifest as press perturbations that cause persistent alterations to the environment. One consequence is that some kelp forests are becoming increasingly sparse and fragmented. We manipulated patch size of the kelp Ecklonia radiata over 24 mo to simulate persistent habitat fragmentation and assessed how this influenced the demography of macro- and microscopic juvenile kelp within the patches. At the beginning of the experiment, patch formation resulted in short-term increases in E. radiata recruitment in patches <1 m2. However, recruitment collapsed in those same patches over the extended period, with no recruits observed after 15 mo. Experimental transplants of microscopic and macroscopic juvenile sporophytes into the patches failed to identify the life stage impacted by the reductions in patch size, indicating that the effects may be subtle and require extended periods to manifest, and/or that another life stage is responsible. Abiotic measurements within the patches indicated that kelp were less able to engineer the sub-canopy environment in smaller patches. In particular, reduced shading of the sub-canopy in smaller patches was associated with proliferation of sediments and turf algae, which potentially contributed to the collapse of recruitment. We demonstrate the consequences of short- and longer-term degradation of E. radiata habitats and conclude that habitat fragmentation can lead to severe disruptions to kelp demography.

In vitro study of Orexin alpha effects on factors involved in atherosclerosis: a dual role?

2019 ◽  
Author(s):  
Angeliki Karapanagioti ◽  
Flora Spenzta ◽  
Georgios K. Dimitriadis ◽  
Narjes Nasiri-Ansari ◽  
Evi Lianidou ◽  
...  
Keyword(s):  
In Vitro Study ◽  
Dual Role ◽  
Vitro Study
Sign in / Sign up

Export Citation Format

Share Document