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1. "Sole or Whole" – Quilting the Racialized Subject Calgary feminist and scholar Aruna Srivastava tackles the complex question of what it means to be "mixed-race/mixedblood/halfbreed/mestizo/hybrid/hyphenated?" in her editorial to Hyphe Nation (1996). In response to her question, this study of contemporary African-Canadian literature suggests that mixed-race Canadians are often constructed as the Other in Canadian society. In consequence, constructions of "racial hybridity" in African-Canadian literature usually aim at carving out a space that doesnt marginalize "racial" mixing but eviscerates restrictive Manichean constructions of identity in order to promulgate concepts of wholeness and self-definition. In consequence, African-Canadian mixed-race writers create hybrid identities that are infinite, multilayered, fragmented and yet whole. They reflect the processes of shifting, overlapping and re-creation in the process of creating identity and can hence be read as representations of complex, de-central, non-hierarchical identities. They are quilting multidimensional racialized subjects. 2. Signifying the In-Between: "Race", "Racial Hybridity" and Questions of Belonging "Race" is not a biological category. Rather it represents a social construction predicated upon the interpretation of difference. It was designed to establish, justify or perpetuate hegemonic social structures and is adherent to the principle of white supremacy. Contemporary "race" theory often neglects the experiences of racially mixed individuals because it fails to offer flexible models of identity in which bi- and multiracial people find themselves represented. This thesis argues in favor of a poetics of difference that accepts and recognizes the heterogeneity of subjectivities while taking into consideration the various dimensions of class, gender, sexuality and ethnicity. Accordingly, constructions of racial hybridity in contemporary African-Canadian literature demonstrate that racism must be acknowledged as an ideology in which people believe and upon which people act. Thus identities often bear the stamp of various histories of resistance and domination, while tackling the question of belonging and re-defining Canadianness. 3. African-Canadian Borderlands References to interracial contacts and the existence of bi- and multiracial people have been omitted from the official founding narratives of the Canadian nation. African-Canadian writers have therefore been successful chroniclers of the past and filled blanks in Canadian historiography in order to shed light on hitherto repressed or erased knowledge. Part of this process is also the inscription of the mixed-race experience into Canadas past. Along this line, bi- and multiracial Canadians often criticize that the state-proclaimed policy of multiculturalism fails to take their manifold racial and ethnic subjectivities into account. 4. "From Sole to Whole" – African-Canadian Mixed-Race Poetics Mixed-race characters in US-American literature often appear in the literary motif of the "tragic mulatto" and it is often implicitly suggested that the bi- or multiracial protagonist is categorized as black. In contrast, African-Canadian constructions of racial hybridity less frequently adhere to the stereotype of the "tragic mulatto" and leave more space for employing alternative modes of racial and ethnic identification. Canadian writers of mixed descent have created a mixed-race poetics that calls attention to contexts, relationships, intersections and wholes. They encourage sites of inclusiveness, incessant shifting and discontinuity in the process of constructing identities. Nevertheless, modes of identification among racially hybrid writers in Canada vary, ranging from detesting whiteness to claiming a Black Nationalist stance. In general, however, they support the idea of fluid and flexible identities. The answer to the initial question of Srivastava is hence given by a vast variety of African-Canadian subject positions. An essentially "black" or "racially mixed" Canadian subject does not exist. Instead, constructions of racial hybridity in African-Canadian literature offer a holistic view of identity and aim at re-conceptualizing the various senses of self and community in Canada. This strategy provides a significant means of self-empowerment and self-reclamation – making racially mixed African-Canadians "whole" instead of "sole".
Until today most social, historical and cultural studies of the American postwar era have contributed to the myth of a relatively homogeneous society and culture. Even though they understood these years as a turning point for modern American society, they failed to encompass the polyvalence and heterogeneity of American society. Focussing mostly on white and middle class males, these studies formed a onedimensional picture of sociocultural conformity, a picture in which issues of gender, race and class were largely absent. Crossing the boundaries of feminist, cultural and historical studies this dissertation starts from identifying the gaps and problems in current academic research. Those sociopolitical structures that affected non-white women are then juxtaposed with the dominant postwar discourse of womanhood. The literary texts by women of color show them grappling with the conflicting demands of socioecnomic realities and pervasive role definitions. On the surface these literary interventions seemed to submit to dominant ideologies while opposing them at the same time. Thus they are both anticipatory and antagonistic. The dissent and criticism in writings by women of color seem to have become a catalyst for the deep social transformations in the following decades.
The thesis is about ideological change of political parties and the way parties gather information, learn by updating their beliefs and ultimately make "rational choices". Analyzing 1451 policy moves of 137 parties in 22 OECD-countries from 1950 to 2013 it is a story about rational learning, about emulating other parties abroad and chasing public opinion. Yet, the "internal life" of a party conditions the effects when activists have some influence over the formation of party policy. As volunteers facing a scarcity of time and resources, members of the party on the ground have a different information horizon, and may arrive at the opposite decision where to move than party elites which (can) rest their decision on a broader set of information resources. In some parties the party on the ground thus constitutes an "internal wall of resistance" to the strategy party elites would choose, if they were free from constraints.
Microbial infections can be either caused by a single species or complex multi-species consortia. One of the most prominent opportunistic human pathogens leading to mono- or mixed-species infections is the Gram-negative bacterium Pseudomonas aeruginosa. Understanding the molecular basis of its adaptation to infection-related stresses is an essential prerequisite for the prevention and treatment of P. aeruginosa infections. We therefore employed state-of-the-art proteomics approaches to elucidate the molecular adaptation mechanisms of P. aeruginosa to infection-related conditions. Moreover, structure, function and interaction of complex microbial consortia containing P. aeruginosa and causing catheter-associated urinary tract infections were investigated by metaproteomics analyses. Our investigations revealed that the adaptation of P. aeruginosa during infection is either based on gene expression changes caused by environmental signal integration or by gene mutations leading to a selective advantage in a particular host environment. In study I, investigating the proteome response of P. aeruginosa biofilms to the clinical relevant antibiotic ciprofloxacin, global changes in the protein profile were observed. Ciprofloxacin induced the expression of proteins involved in the Lex-induced SOS-response, drug efflux pumps and gene products of the ciprofloxacin-responsive prophage cluster and repressed the expression of porins and DNA-binding proteins. In study II the transcriptome and proteome of two clonal P. aeruginosa lineages during long-term colonization of cystic fibrosis (CF) patient’s lungs were analyzed. Point mutations in global regulator genes, i.e. retS, gacS, and gacA, were identified by genomic sequencing. Inactivation of RetS, found two years after the initial colonization, induced the expression of genes involved in chronic infections and coding for the type 6-secretion system (T6SS). Additional mutations in the GacS/GacA two-component regulatory system (TCS) were found to repress the expression of T6SS proteins and to induce the expression of proteins belonging to the type 3-secretion system (T3SS). In study III we elucidated the niche-specific adaptation of P. aeruginosa isolates from different infection sites by investigating their protein expression patterns and glucose metabolic fluxes. We could show that isolates from the urinary tract express a higher amount of proteins involved in the acquisition of micronutrients (i.e. iron) and carbohydrates compared to isolates from the CF lung. In study IV 16S rDNA sequencing and metaproteomics were employed to demonstrate that the investigated CAUTI-related biofilms consisted of two to five different species with one or two species dominating the mixed community. Following this line of research, we investigated in study V structure and function of a biofilm of a long-term catheterized patient, which was predominantly composed of P. aeruginosa and Morganella morganii, but also contained a minor proportion of the obligate anaerobe Bacteroides sp.. The comparison of in vivo and in vitro protein expression profiles of P. aeruginosa and M. morganii indicated that iron and carbohydrates are the major growth-limiting factors in the bladder. These results indicate different nutritional strategies of the two pathogens in the bladder environment. A comparison of urinary protein profiles of healthy persons and catheterized patients suggested that the human innate immune system is induced by CAUTIs. Moreover, numerous proteins involved in nutritional immunity, e.g. iron-, calcium- and magnesium-binding proteins, were found to be more abundant in the urine of catheterized patients. A follow-up (meta)proteomics study (study VI) aiming at the elucidation of interspecies interactions during multi-species infections indicated that the urease-positive uropathogen Proteus mirabilis induces the precipitation of metal ions by urine alkalization and thereby limits the availability of these important micronutrients for other co-infecting bacteria. This limitation seems to be sensed by the P. aeruginosa PhoP-PhoQ two-component system (TCS) leading to an increased resistance to antimicrobial peptides and biofilm-forming capacity of the pathogen. Also during co-cultivation of P. aeruginosa with Staphylococcus aureus a slight increase in the expression of the PhoP-PhoQ TCS and the alkaline protease could be observed (study VII). In study VIII a combined metagenomics and metaproteomics approach was employed to investigate structure and function of the lichen Lobaria pulmonaria, a complex consortium consisting of a fungus, an algal partner, cyanobacteria, and a highly diverse bacterial microbiome. The results presented in this work contribute to a better understanding of the manifold and complex bacterial adaptation mechanisms to infection-related and environmental stress and thereby foster the development of novel treatment and prevention strategies.
Manipulating and utilizing plasmas becomes a more and more important task in various research fields of physics and in industrial developments. Especially in nowadays spacerelevant applications there are different ideas to modify plasmas concerning particular tasks.
One major point of interest is the ability to influence plasmas using magnetic fields. To study the underlying physical effects that were achieved by these magnetic fields for both scenarios Particle-in-Cell simulations were done. Two examples are discussed in this thesis.
The first example originates from an experiment performed by the European Space Agency ESA in collaboration with the German Space Agency DLR. To verify the possibility of heat-flux reduction by magnetic fields onto the thermal protection system of a space vehicle a simplified experiment on earth was developed. Most of the heat that is created during re-entry comes from compression of the air ahead of the hypersonic vehicle, as a result of the basic thermodynamic relation between temperature and pressure. The shock front, which builds up in front of the vehicle deflects most of the heat and prohibits the surface of the space vehicle from direct contact with the maximum flux. State of the art spacecrafts use highly developed materials like ceramics to handle the enormous heat. An attractive approach to reduce costs is to use magnetic fields for heat-flux reduction. This would allow the use of cheaper materials and thus reduce costs for the whole space mission. A partially-ionized Argon beam was used to create a certain heat-flux onto a target. The main finding of the experimental campaign was a large mitigation of heat-flux by applying a dipole-like magnetic field. The Particle-in-Cell method was able to reproduce experimental observations like the heat-flux reduction. An additionally implemented optical diagnostics module allowed to confirm the results of the spectroscopy done during the experiment. The underlying effect that is responsible for the heat-flux reduction was identified as a coupling between the modified plasma and the dominating neutral flux component. The plasma, that is guided towards the target, act as a shield in front of the target surface for arriving neutrals. These neutrals are slowed down by charge-exchange collisions. Furthermore the magnetic field induces an increased turbulent transport that is also needed to reach a reduction in heat-ux. The turbulent transport was also obtained by three-dimensional Direct Simulation Monte Carlo simulations. Unfortunately, such source driven turbulence can not be expected in space, so that a heat flux reduction in real space applications is questionable. Nevertheless, other effects like the induced turbulence by the rotating vehicle can compensate the missing source driven effect.
The second scenario in which a magnetic field is used to modify the heat flux of a plasma is the operation of the pulsed cathodic arc thruster. The same Particle-in-Cell code was used to simulate a typical pulse of this newly developed thruster of Neumann Space Pty Ltd. The typical behavior of the thruster could be reproduced numerically. The thrust is mainly produced by fast electrons. These electrons are accelerated by electric fields as a result of a plasma-beam instability. This plasma-beam instability was verified by a phase space diagnostics for the electrons. To demonstrate the influence of the magnetic field a simulation of the cathodic arc thruster without magnetic field and one with magnetic field were compared. It was shown that the use of a magnetic field leads to a ten times larger thrust by directing the heat ux. The resulting narrow plume is an additional Advantage of the particle guiding magnetic field. This narrowness of the plume reduces the danger of interaction with other components of the space vehicle.
Both scenarios demonstrate the different capabilities for electromagnetic fields to manipulate plasmas and especially the corresponding heat-flux with respect to certain tasks. The possibilities range from reducing the heat-flux onto a target to maximizing the thrust by directing the heat-ux. This thesis demonstrates that simulations are a great tool to support experiments and to deliver an improved physics understanding. They help to identify the basic physics principles in the different systems, because they can deliver information not accessible to experiments.
In particular, a better understanding of the influence of electromagnetic fields on the heat-flux distribution in space-relevant applications was obtained. This can be the basis for further simulation-guided optimization, e.g. for the design of more effective cathodic arc thrusters. Here, the goal is to minimize costs for prototypes by replacing the hardware by virtual prototypes in the simulations. This allows to test basic design ideas in advance and get more highly-optimized designs at a fraction of time and costs.
Until today, more than 17% of the population in Mecklenburg Western-Pomerania suffer from chronic kidney disease (CKD) which was revealed by the SHIP study (Study of Health in Pomerania). 20% of CKD cases can be traced back to glomerulopathies. One common characteristic of glomerulopathies is the morphologic change of the glomerular filtration barrier which consists of endothelial cells, the glomerular basement membrane and podocytes. Under healthy conditions, the foot processes of the podocytes interdigitate with the foot processes of the neighboring podocytes with a filtration slit in between. Apart from the slit membrane protein nephrin, typical adherens junction proteins like occludin or JAM-A are also expressed at this cell-cell junction. This junction is therefore considered to be a specialized type of adherens junction, necessary to maintain the size-selectivity of the filtration barrier. During podocyte injury, podocyte foot processes lose their characteristic morphology and the typical meandering filtration slit becomes linearized, a process which is described as foot process effacement.
Since morphological change is directly linked to change or loss of function, ultrastructural analysis of the foot processes is necessary for diagnostics and research. By using 3D-structured illumination microscopy (3D-SIM), we quantified these morphological changes as well as studied a possible biomarker, the tight junction protein claudin 5 (CLDN5). Our study showed a spatially restricted up-regulation of CLDN5 in effaced filtration slit areas in biopsies of patients suffering from minimal change disease (MCD), focal and segmental glomerulosclerosis (FSGS) as well as in mice after NTS injection and in the uninephrectomy DOCA-salt mouse model. CLDN5/nephrin ratios of biopsies from patients with glomerulopathies and of tissue received from NTS-treated mice were significantly higher compared to controls. We found that in patients the CLDN5/nephrin ratios were negatively correlated with the filtration slit density. Since CLDN5 up-regulation was observed in several areas of high filtration slit density, we hypothesized that CDLN5 upregulation preceded visible foot process effacement. Taken together, we suggest that CLDN5 could be a helpful biomarker to identify an early change of the foot process morphology in addition to filtration slit density measurement. Additionally, correlation analysis of foot process effacement with patient data showed a significant negative correlation of the filtration slit density with proteinuria in MCD patients.
Nowadays, a challenge in wildlife management and nature conservation is to reach a state of human-wildlife coexistence, integrating wildlife into the human-dominated landscape. Achieving a state of coexistence is urgent as human-wildlife conflicts increase over time. Thus a "route guide" for researchers and conservation practitioners will be needed to identify if a human-wildlife interaction is heading towards conflict or coexistence, enabling them to conduct management activities, when possible, to achieve human-wildlife coexistence. Researchers have used different individual-based attributes as a proxy to measure support towards wildlife species by the general public. Different operationalizations from Environmental Economics and Environmental and Conservation Psychology research fields have been used to measure support. Examples of operationalization are the willingness-to-pay and Likert-type scale, or rating scale, from the first and second research fields. In the first, participants must indicate how much they would be willing to pay to protect a specific wildlife species population in a particular area and time. In the second, participants are asked to rate statements through, e.g., a five-point ordinal rating scale with opposite alternatives between, e.g., strongly agree and strongly disagree. In the human dimension of natural resources management research, variations of these methodologies have been used to measure support, not only for one wildlife species but for a set. For the willingness-to-pay variation, i.e., money allocation, participants must distribute a constant sum of money among a set of wildlife species. For the rating scale variation, each of the wildlife species in the set corresponds to a statement to be rated. The thesis aims to contrast these two variations, i.e., money allocation and rating scale, in their capacity to assess support changes towards a set of 12 native wildlife species from different taxa.
A survey was applied in 2018 (n: 368) and replicated in 2019 (n: 359) among urban dwellers who cohabit with the wildlife species set, in Valdivia, south of Chile. The surveys were applied before and after information disclosure and exposure in an experimental and longitudinal research design structure, respectively. As information disclosure, the threatened and endemic status of the wildlife species was presented to the participants. On the other hand, mass media coverage of a human-wildlife conflict involving one of the species included in study, the South American Sea Lion, was used for information exposure. The results indicate that the money allocation method identified support changes among the wildlife species to a greater extent than the rating scale for both types of information (Chapters 2, 3, and 4). The money allocation in the experimental design structure grouped the wildlife species based on their threatened and endemic status, while the rating scale did not come with the same results (Chapter 3). In the longitudinal design structure, the South American Sea Lion support decreased based on the average values of the money allocation and rating scale after the information exposure (Chapter 4). Differently, when the South American Sea Lion position support is compared with the other wildlife species, based on the money allocation, there was a descent, while the rating scale presented an ascent after the mass media coverage of the human-wildlife conflict (Chapter 4). This difference between the results of the two methods, in both research design structures, can be explained to a certain extent due to their scaling technique characteristics. The money allocation is a comparative scale; therefore, the support given to one wildlife species will affect the possible support given to the other species. In contrast, the rating scale is a non-comparative scale, i.e., the support given to a wildlife species is independent of the support given to the other wildlife species in the set. In the experimental research design structure (Chapters 2 and 3), to give or increase the support to a threatened or endemic wildlife species, a bill should be taken from another wildlife species, usually not threatened nor endemic. On the contrary, in the rating scale, there was no need to choose; the support could be increased for a wildlife species without decreasing the support for other wildlife species. In the longitudinal study design structure, the money allocation allows direct comparison between wildlife species from one year to another, while the rating scale does not. For the money allocation, the possible amount of support to be given to a wildlife species, i.e., 12 bills of 1,000 CLP each, did not vary from 2018 to 2019. For the rating scale, the values received among the wildlife species can vary within the rating scale from one year to another, misleading to incorrect interpretations. The money allocation method can be suitable for monitoring human-wildlife interactions, i.e., to position and visualize support shifts. The money allocation could be used as an overview of human-wildlife interactions in a specific area, working as a first assessment.
Pentathiepins are cyclic polysulfides that exert antiproliferative and cytotoxic activity in cancer cells, induce oxidative stress and apoptosis, and potently inhibit GPx1. These properties render this class of compounds promising candidates for the development of anticancer drugs. However, the biological effects and how they intertwine to promote high cytotoxicity have not been systematically assessed throughout a panel of cancer cell lines from distinct tissues of origin. In this thesis, six novel pentathiepins were analyzed and constitute the second generation of compounds with additional properties such as fluorescence or improved water solubility to facilitate cellular testing. All compounds underwent extensive biological evaluation in 14 human cancer cell lines. These studies included investigations of the inhibitory potential with regards to GPx1 and cell proliferation, examined the cytotoxicity in human cancer cell lines, as well as the induction of oxidative stress and DNA strand breaks. Furthermore, selected hallmarks of apoptosis, ferroptosis, and autophagy were studied. Experimental approaches regarding these cellular mechanisms included observing morphological changes, detecting phosphatidyl serine exposure and caspase activity, and quantifying cleaved PARP1 and levels of LC3B II. In addition, the analysis of the cell cycle aimed to identify aberrations or arrests in cell division.
Five of the six tested pentathiepins proved to be potent inhibitors of the GPx1, while all six exerted high cytotoxic and antiproliferative activity, although to different extents. There was a clear connection observed between the potential to provoke oxidative stress and damage to DNA in the form of single- and double-strand breaks both extra- and intracellularly. Furthermore, various experiments supported apoptosis but not ferroptosis as the mechanism of cell death in four different cell lines. In particular, the externalization of PS, the detection of activated caspases, and the cleavage of PARP1 corroborated this conclusion. Additionally, indications for autophagy were found, but more investigations are required to verify the current data. The findings of this dissertation are mainly in line with the postulated mechanism of action proposed for pentathiepins and a previous publication from our group that described their biological activity. However, the influence of modulators such as oxygen and GSH on the biological effects was ambiguous and dependent on the compound. The expression profile of the cell lines concerning GPx1 and CAT did not influence the cellular response toward the treatment, whereas the cell doubling time correlated with the cytotoxicity.
As the various pentathiepins give rise to different biological responses, modulation of the biological effects depends on the distinct chemical structures fused to the sulfur ring. This may allow for future optimization of the anticancer activity of pentathiepins. An analysis of the structure-activity relationships revealed that the piperazine scaffold was associated with superior biological activity compared to the pyrrolo-pyrazine backbone. Furthermore, substituents with electron-withdrawing properties or those providing a free electron pair, such as fluorine or morpholine, were advantageous. These findings should help design and synthesize the next generation of pentathiepins, thereby expanding the library of compounds, allowing for the further deduction of structure-activity relationships and an improved understanding of their mechanism of action.
The present experimental work investigates plasma turbulence in the edge region of magnetized high-temperature plasmas. A main topic is the turbulent dynamics parallel to the magnetic field, where hitherto only a small data basis existed, especially for very long scale lengths in the order of ten of meters. A second point of special interest is the coupling of the dynamics parallel and perpendicular to the magnetic field. This anisotropic turbulent dynamics is investigated by two different approaches. Firstly, spatially and temporally high-resolution measurements of fluctuating plasma parameters are investigated by means of two-point correlation analysis. Secondly, the propagation of signals externally imposed into the turbulent plasma background is studied. For both approaches, Langmuir probe arrays were utilized for diagnostic purposes. The main findings can be summarized as follows: Greatly elongated fluctuation structures exist in plasma edge turbulence. The structures are aligned along the confining magnetic field (k|| = 0). The correlation degree of fluctuations for a short connection length of 0.75m is greater than 80%. For much longer connection lengths of 23m and 66m, the correlation degree is reduced to approximately 40%. A conceptual interpretation of these observations is the coexistence of two different fluctuation components. One component has a correlation length parallel to the magnetic field below 20m and the other component a correlation length greater than 70m. Sine signals in the frequency range 1-100 kHz were injected into the turbulent plasma background. The propagation parallel and perpendicular to the magnetic field of the signals was studied. In poloidal direction, an asymmetry is observed, that can be explained by a copropagation of the signal with the background E × B-rotation of the plasma. The signal propagation parallel to the magnetic field shows no such asymmetry. As an advanced approach, spatio-temporal wave patters were injected into the edge plasma. The waves launched that way can be seen as test waves' in a turbulent background. The coupling strength of the imposed wave patterns to the background turbulence relies on the match of the imposed waves to the dynamics of turbulent structures. If the propagation direction of the imposed waves is parallel to the propagation direction of the background plasma, improved coupling is observed. This finding underlines the importance of the background plasma rotation for future attempts of controlling the plasma edge turbulence. Further optimization of frequency and wave vector of the imposed waves is probably a promising approach for achieving a significant and systematic influence of turbulence. Taking into account the present experimental state-of-the-art, for a deeper insight into the mechanism of the plasma edge turbulence of magnetized high-temperature plasmas a joint effort of numerical modeling and experimental results is a valuable approach. Such a cooperation should cover the explanation of the correlation observations as well as the experiments on signal injection into background turbulence. A quantitative comparison between the results presented in this work and a dedicated numerical drift wave simulation would be a significant step forward to a better understanding of plasma edge turbulence.
Serbian Tertiary ultrapotassic province is part of widespread but not voluminous basaltic magmatism in Serbia. Two principal groups of ultrapotassic rocks are recognized; the lamproite affinity group (LAG) and the kamafugite affinity group (KAG). My results demonstrate three dominant low-pressure evolutional processes: magma mixing and fractional crystallization, analcimization and heteromorphism. The two suites of ultrapotassic rocks show large ranges of Sr and Nd isotopic values but a restricted variation of Pb isotopes. LAG is characterized by wide ranges of Sr and Nd isotopes (87Sr/86Sri 0.70735- 0.71299, 143Nd/144Ndi 0.51251-0.51216). KAG is isotopically homogeneous with a limited range of Sr-Nd isotopes (87Sr/86Sri 0.70599-0.70674, 143Nd/144Ndi 0.51263-0.51256). The Pb isotope compositions of both groups are similar (206Pb/204Pb 18.581-18.832, 207Pb/204Pb 15.624-15.696 and 208Pb/204Pb 38.744-38.987), and fall within the pelagic sediment field resembling Mesozoic flysch sediments from the Vardar ophiolitic composite suture zone. Highly variable Sr and Nd isotopic signatures of primitive-LAG rocks correlate with REE fractionation and enrichment of the HFSE. I explain this correlation using vein+wall-rock melting model, invoking the presence of different metasomatic domains (veins with phlogopite, Cpx and F-apatite) that are out of isotopic equilibrium with the peridotite wall rock. Relatively uniform Sr and Nd isotopic data of KAG rocks, similar trace element patterns and small but regular variations of HFSE ratios, indicate different degrees of melting of a relatively homogeneously metasomatized mantle source. Geochemical modelling implies the role of phlogopite, apatite and Ti-oxide in their mantle source.