Lichens and their importance for the monitoring of environmental changes in Southern Africa : with special reference to soil-inhabiting lichens.

Lichens are the object of investigation within the framework of the BIOTA Southern Africa project, subproject S04 (http://www.biota-africa.org). This interdisciplinary research project, installed in 2000, focuses on the analysis of biodiversity and its changes along climatic and vegetation gradients (transects) in Namibia and in the Republic of South Africa. In the context of this project, studies on the diversity of lichens are carriedout. Special reference is given to the monitoring of lichens growing on soil, which form the so called biological soil crusts.Lichen diversity is assessed and analysed with respect to its spatial and temporal changes. These are related to various abioticand biotic factors such as climate, soil features and land use. The indicator value of certain terricolouslichen taxaand/or lichen groups (communities) is investigated for the study area, and it is intended to use itin a future long-term monitoring programme in the region. In this brochure, we whish to explain what lichens are, how do they live and where do they grow, and why they are so important as bioindicatorsin arid and semi-arid areas of the world. The activities of the S04 subproject along the BIOTA transect are described, as well as the methods used for monitoring environmental changes in Southern Africa using soil-inhabiting lichens

Mitochondrial Dynamics at the Interface of Immune Cell Metabolism and Function

Immune cell differentiation and function are crucially dependent on specific metabolic programs dictated by mitochondria, including the generation of ATP from the oxidation of nutrients and supplying precursors for the synthesis of macromolecules and post-translational modifications. The many processes that occur in mitochondria are intimately linked to their morphology that is shaped by opposing fusion and fission events. Exciting evidence is now emerging that demonstrates reciprocal crosstalk between mitochondrial dynamics and metabolism. Metabolic cues can control the mitochondrial fission and fusion machinery to acquire specific morphologies that shape their activity. We review the dynamic properties of mitochondria and discuss how these organelles interlace with immune cell metabolism and function

Cell biology, SevERing mitochondria

The endoplasmic reticulum is an active participant in the division of another organelle, the mitochondrion

TransparentHMD: Revealing the HMD User's Face to Bystanders

While the eyes are very important in human communication, once a user puts on a head mounted display (HMD), the face is obscured from the outside world's perspective. This leads to communication problems when bystanders approach or collaborate with an HMD user. We introduce transparentHMD, which employs a head-coupled perspective technique to produce an illusion of a transparent HMD to bystanders. We created a self contained system, based on a mobile device mounted on the HMD with the screen facing bystanders. By tracking the relative position of the bystander using the smartphone's camera, we render an adapting perspective view in realtime that creates the illusion of a transparent HMD. By revealing the user's face to bystanders, our easy to implement system allows for opportunities to investigate a plethora of research questions particularly related to collaborative VR systems

Targeting of the prion protein to the cytosol: mechanisms and consequences

Prion diseases are characterized by the conformational transition of the cellular prion protein (PrPC) into an aberrant protein conformer, designated scrapie-prion protein (PrPSc). A causal link between protein misfolding and neurodegeneration has been established for a variety of neurodegenerative disease, such as Alzheimer's disease, Parkinson's disease and polyglutamine diseases, but there is an ongoing debate about the nature of the neurotoxic species and how non-native conformers can damage neuronal populations. PrP is normally imported into the endoplasmic reticulum (ER) and targeted to the outer leaflet of the plasma membrane via a glycosylphosphatidylinositol (GPI) anchor. However, several conditions, such as ER stress or some pathogenic mutations in the PrP gene, can induce the mislocalization of PrP in the cytosol, where it has a neurotoxic potential as demonstrated in cell culture and transgenic mouse models. In this review we focus on intrinsic factors and cellular pathways implicated in the import of PrP into the ER and its mistargeting to the cytosol. The findings summarized here not only reveal a complex regulation of the biogenesis of PrP, but also provide interesting new insight into toxic activities of pathogenic protein conformers and quality control pathways of ER-targeted proteins

Testing of the Semicircular Canal Function in Vertigo and Dizziness

Testing the function of the semicircular canals (SCC) in vertigo and dizziness is an important step towards a diagnosis. There are different vestibular tests available: rotatory testing, bithermal caloric irrigation (CI) and the video-head-impulse test (vHIT). This chapter describes the basic methods, the current knowledge and economic aspects focused on the vHIT and CI. After a general section, common vertigo diseases are discussed with respect to the functional tests. From this chapter, it is clear that not only one method has to be applied to test vestibular function but a battery including the CI and the vHIT in three dimensions

Mechanisms of mitochondria and autophagy crosstalk

Autophagy is a cellular survival pathway that recycles intracellular components to compensate for nutrient depletion and ensures the appropriate degradation of organelles. Mitochondrial number and health are regulated by mitophagy, a process by which excessive or damaged mitochondria are subjected to autophagic degradation. Autophagy is thus a key determinant for mitochondrial health and proper cell function. Mitophagic malfunction has been recently proposed to contribute to progressive neuronal loss in Parkinson's disease. In addition to autophagy's significance in mitochondrial integrity, several lines of evidence suggest that mitochondria can also substantially influence the autophagic process. The mitochondria's ability to influence and be influenced by autophagy places both elements (mitochondria and autophagy) in a unique position where defects in one or the other system could increase the risk to various metabolic and autophagic related diseases

Types of identification keys

A number of terms related to identification tools are introduced and the advantages of selected types of identification keys are compared

Fatty acid trafficking in starved cells: regulation by lipid droplet lipolysis, authophagy and mitochondrial fusion dynamics

Fatty acids (FAs) provide cellular energy under starvation, yet how they mobilize and move into mitochondria in starved cells, driving oxidative respiration, is unclear. Here, we clarify this process by visualizing FA trafficking with a fluorescent FA probe. The labeled FA accumulated in lipid droplets (LDs) in well-fed cells but moved from LDs into mitochondria when cells were starved. Autophagy in starved cells replenished LDs with FAs, increasing LD number over time. Cytoplasmic lipases removed FAs from LDs, enabling their transfer into mitochondria. This required mitochondria to be highly fused and localized near LDs. When mitochondrial fusion was prevented in starved cells, FAs neither homogeneously distributed within mitochondria nor became efficiently metabolized. Instead, FAs reassociated with LDs and fluxed into neighboring cells. Thus, FAs engage in complex trafficking itineraries regulated by cytoplasmic lipases, autophagy, and mitochondrial fusion dynamics, ensuring maximum oxidative metabolism and avoidance of FA toxicity in starved cells