13 research outputs found
Methods for detecting channel bed surface changes in a mountain torrent – experiences from the Dorfbach torrent
The erosion of and depositions on channel bed surfaces are instrumental to
understanding debris flow processes. We present an overview of existing
field methods and highlight their respective advantages and disadvantages.
Terrestrial laser scanning (TLS), airborne laser scanning (ALS), erosion
sensors, cross sections (CS) and geomorphological mapping are compared.
Additionally, two of these approaches (i.e. TLS and CS) are tested and
applied in the channel reaches of the torrent catchments. The results of the
comparison indicate that the methods are associated with variable temporal
and spatial resolution as well as data quality and invested effort. TLS data
were able to quantify small-scale variations of erosion and deposition
volumes. While the same changes could be detected with CS and
geomorphological mapping, it was only possible with lower precision and
coarser spatial resolution. The study presents a range of potential methods
that can be applied accordingly to address the objectives and to support the
analyses of specific applications. The availability of erosion data,
acquired mainly by TLS and ALS, in combination with debris-flow monitoring
data, provides promising sources of information to further support torrent
risk management
Methods for detecting channel bed surface changes in a mountain torrent – experiences from the Dorfbach torrent
Monitoring of erythropoiesis by the serum transferrin receptor and erythropoietin.
Virtually all cells have transferrin receptors (a transmembrane glycoprotein) on their surface but in a normal adult, 80% of them are in the erythroid marrow. Some of them are lost into the circulation where they can be measured by immuno-assays. A direct and highly significant correlation exists between serum transferrin receptor level and erythron transferrin uptake in humans. The measurement of serum transferrin receptor has wide clinical applications for the quantitation of erythropoiesis. It can be used to study erythropoiesis in situations in which ferrokinetics is not acceptable such as pregnancy. It is particularly useful for serial studies, e.i., for monitoring the recovery of erythropoiesis after stem cell transplantation or after treatment with erythropoietin. Combined with the determination of serum erythropoietin, both evaluated in relation to the degree of anemia, they provide a physiological approach to the diagnosis of anemia. Thus, the simultaneous determination of hematocrit, reticulocytes, serum transferrin receptor and serum erythropoietin has high discriminatory value in distinguishing between a defect in erythroid proliferation, maturation or red cell survival. It is also particularly useful for detecting the presence of multiple mechanisms of anemia in the same patient