Pyroxenite xenoliths from Marsabit (Northern Kenya): evidence for different magmatic events in the lithospheric mantle and interaction between peridotite and pyroxenite

Garnet-bearing and garnet-free pyroxenite xenoliths from Quaternary basanites of Marsabit, northern Kenya, were analysed for microstructures and mineral compositions (major and trace elements) to constrain the thermal and compositional evolution of the lithospheric mantle in this region. Garnet-bearing rocks are amphibole-bearing websterite with ~5-10 vol% orthopyroxene. Clinopyroxene is LREE-depleted and garnet has high HREE contents, in agreement with an origin as cumulates from basaltic mantle melts. Primary orthopyroxene inclusions in garnet suggest that the parental melts were orthopyroxene-saturated. Rock fabrics vary from weakly to strongly deformed. Thermobarometry indicates extensive decompression and cooling (~970-1,100°C at ~2.3-2.6GPa to ~700-800°C at ~0.5-1.0GPa) during deformation, best interpreted as pyroxenite intrusion into thick Paleozoic continental lithosphere subsequently followed by continental rifting (i.e., formation of the Mesozoic Anza Graben). During continental rifting, garnet websterites were decompressed (garnet-to-spinel transition) and experienced the same P-T evolution as their host peridotites. Strongly deformed samples show compositional overlaps with cpx-rich, initially garnet-bearing lherzolite, best explained by partial re-equilibration of peridotite and pyroxenite during deformation and mechanical mingling. In contrast, garnet-free pyroxenites include undeformed, cumulate-like samples, indicating that they are younger than the garnet websterites. Major and trace element compositions of clinopyroxene and calculated equilibrium melts suggest crystallisation from alkaline basaltic melt similar to the host basanite, which suggests formation in the context of alkaline magmatism during the development of the Kenya rif

Entwicklung und Anwendung eines Computerprogrammes zur numerischen Modellierung von Diffusionsprofilen in Mineralkörnern

Zur Durchführung von numerischen Diffusionsmodellierungen wurde ein neues Modell entwickelt. Dieses beruht auf dem Crank-Nicolson-Algorithmus und simuliert die dreidimensionale isotrope Diffusion beliebiger Elemente in einem kugelförmigen Mineral. Für die Anwendung wurden drei lithologisch unterschiedliche Probensuiten aus verschiedenen tektonischen Szenarien ausgewählt. Die granatpyroxenitischen und -websteritischen Xenolithe des Marsabit-Schildvulkans dokumentieren eine dreiphasige thermobarische Entwicklung. Die seit dem Miozän stattfindene Abkühlung mit einer Abkühlungsrate von -20 bis -60 °C/Ma wurde durch die thermische Subsidenz im Bereich des Anza-Grabens verursacht. Während oder nach der Abkühlung erfolgte eine Dekompression um ca. 0.3-0.8 GPa entsprechend einer Anhebung um ca. 9-24 km. Dieses Ereignis kann mit sehr jungen Extensionsbewegungen im Bereich des Anza-Grabens in Verbindung gebracht werden. Die sehr junge (16-260 ka) Aufheizung wurde durch die Verlagerung des Vulkanismus vom Kenia-Rift auf die östliche Grabenschulter verusacht. Die Modellierung von Spurenelement-Zonierungen in den Granaten ergab folgende relative Diffusionskoeffizienten: Fe-Mg > Ni > Ti > Sc ª V. Die für die Granate des Alpe-Arami-Peridotit-Körpers durchgeführten Modellierungen belegen sehr hohe Abkühlungsraten von -120 bis -2600 °C/Ma innerhalb von 0.1-3.2 Ma. Diese Abkühlung wurde höchst wahrscheinlich durch die Einschuppung des heißen Peridotit-Körpers in die kalte Cima-Lunga-Decke verursacht. Die Zeitdauer der Hochtemperatur-Metamorphose (T = 870-980 °C, P * 1.0-1.5 GPa) der Granulite aus den 'metamorphic soles' des 'Central Dinaric Opiolite Belt' konnte auf < 1 Ma festgelegt werden. Dieser sehr kurze Zeitraum unterstützt die Annahme einer innerozeanischen Überschiebung zweier Bereiche von junger ozeanischer Lithosphäre und die damit einhergehende Kontaktmetamorphose als Ursache für die Bildung dieser 'metamorphic soles'

Erbulak (Altan)

Taha Toros Arşivi, Dosya No:38-40-Altan Erbula

Effects of atrazine and climate change on amphibian larval development and growth

University of Minnesota Ph.D. dissertation. April 2014. Major: Integrated Biosciences. Advisor: Lucinda Johnson. 1 computer file (PDF); xiv, 222 pages.The distribution and population persistence of many North American amphibians depends on environmental factors at multiple spatial scales. Anthropogenic and naturally occurring stressors, including contaminants, predators, and pond-drying, have been shown to affect amphibian growth, development, and health. The herbicide atrazine (2-chloro-4-ethylamino-6-isoproyl-amino-s-triazine) is a widely used pesticide in the U.S., and in some amphibians has been shown to reduce size and health at metamorphosis and alter gonadal function, presumably through endocrine disruption. Environmental changes predicted by climate models could exacerbate these impacts, as well as directly affect amphibian development and population persistence through accelerated pond-drying and habitat loss or modification. Objectives of this project were to: 1) Quantify developmental responses to the combined effects of atrazine exposure and accelerated pond-drying rates; and 2) Quantify potential effects of these and other environmental stressors on amphibian occurrence and health. Growth, development, and physiological state (skeletal/eye malformations and gonadal development) were assessed in northern leopard frog (Rana pipiens) and wood frog (Rana sylvatica) in experimental exposures and field surveys in the U.S. Prairie Pothole Region across a range of environmentally relevant atrazine concentrations (0.1, 20, and 200 &mu;g/L) and in combination with climate change and other environmental factors suspected to affect amphibian larval development. Atrazine exposure during larval development decreased survival and had sub-lethal impacts on growth and development, which could negatively impact populations by reducing annual recruitment and survival of juveniles. Presence, abundance, and severity of testicular oocytes (TOs) did not appear to be related to atrazine exposure in experimental or field specimens; however, TO prevalence differed greatly between species (>40% in R. pipiens and R. sylvatica). These results suggest that TOs are not likely due solely to endocrine disruption by atrazine and more research is needed to understand reproductive or population-level impacts of TOs. Amphibian metrics (presence, breeding, skeletal malformations, and TOs) responded differently to environmental variables from wetland, local, and landscape scales, and amphibian breeding (presence or success) was identified as a better indicator of environmental condition than species presence, calling, or TOs

The impacts of sex and the 5xFAD model of Alzheimer’s disease on the sleep and spatial learning responses to feeding time

IntroductionThe relationships between the feeding rhythm, sleep and cognition in Alzheimer’s disease (AD) are incompletely understood, but meal time could provide an easy-to-implement method of curtailing disease-associated disruptions in sleep and cognition. Furthermore, known sex differences in AD incidence could relate to sex differences in circadian rhythm/sleep/cognition interactions.MethodsThe 5xFAD transgenic mouse model of AD and non-transgenic wild-type controls were studied. Both female and male mice were used. Food access was restricted each day to either the 12-h light phase (light-fed groups) or the 12-h dark phase (dark-fed groups). Sleep (electroencephalographic/electromyographic) recording and cognitive behavior measures were collected.ResultsThe 5xFAD genotype reduces NREM and REM as well as the number of sleep spindles. In wild-type mice, light-fed groups had disrupted vigilance state amounts, characteristics, and rhythms relative to dark-fed groups. These feeding time differences were reduced in 5xFAD mice. Sex modulates these effects. 5xFAD mice display poorer spatial memory that, in female mice, is curtailed by dark phase feeding. Similarly, female 5xFAD mice have decreased anxiety-associated behavior. These emotional and cognitive measures are correlated with REM amount.DiscussionOur study demonstrates that the timing of feeding can alter many aspects of wake, NREM and REM. Unexpectedly, 5xFAD mice are less sensitive to these feeding time effects. 5xFAD mice demonstrate deficits in cognition which are correlated with REM, suggesting that this circadian-timed aspect of sleep may link feeding time and cognition. Sex plays an important role in regulating the impact of feeding time on sleep and cognition in both wild-type and 5xFAD mice, with females showing a greater cognitive response to feeding time than males

EPIC OF FATIMAH

Daughter of Prophet Muhammad, wife of Ali and mother of Hasan and Husayn, Fatimah was a very important person in the history of Islam. She is a role model to Muslim women with her morality and piousness. It is said that six months after the death of Prophet Muhammad, Fatimah died because of deep sorrow. In this piece of work, Fatimah's sorrow for her father's death, her sorrow and worry for her two children - Hasan and Husayn - upon learning that she would die, her two children's grief for their mother, and Ali's lament for his wife are profoundly reflected in a plain language. Like many religious and sufic work, there are many copies of this work in Turkish libraries. The copies we have worked with are the ones archived with the number of 5905 and 5906, among the manuscripts of Konya Koyunoglu City and Museum Library. In the writing no. 5905, it is clearly written that the date of 3 Muharram 1239 (9th of September, 1823) was the completion date of the writing. The writings we have worked contained wovel points, and therefore we had the chance to examine labial harmony. With this information, it is understood that writing no. 5906 was copied beginning from 18th century. The work is a typical example of Old Oghuz Turkish language. The copyright form of the writing belongs to the 15th century and after, and the copied form belongs to the 18th century and after. There are studies of Mehmet Mahfuz Soylemez, Muhammet Kuzubas and Saban Dogan, on different copies. With this study, we aim to bring this representative work of Old Oghuz Turkish and Islamic Turkish literature in the world of science. Future studies in line with this purpose are very important to show the historical process of Turkish language

COMPANY TOWNS: THE PATRONAGE SYSTEM FROM MEDIEVAL EUROPE TO THE AMERICAN SOUTH AND BEYOND

M.A.L.S.Many people assume the patronage system was a passing form of control in Medieval Europe, and the system simply vanished. This thesis argues that the patronage system moved from Medieval Europe to the American South and many of the aspects seen in Europe were able to adapt or evolve to fit the modern times. This system was built on large-scale land holdings, agrarian societies, reciprocal obligations, and a control that came from the local area without interference from any national powers. It is because of these aspects that patronage is not confined to any specific time, but has persisted to the modern day.This paper discusses the historiography of the system of patronage found both in Medieval Europe and the American South. By comparing what is written about these systems it is possible to extrapolate the importance of patronage in these societies. Although few write about the system of patronage moving from one period to another, the descriptions used to discuss the periods have striking similarities.In addition to discussing the similarities between the systems it is also imperative to discuss the differences. This allows us to determine whether the differences are a product of the system evolving, or whether the difference proves that an aspect is inherent to one period and not a necessity of patronage.Finally, the paper will briefly discuss how patronage has the power to exist into modern times. While the system has mostly disappeared from the developed countries it still exists in countries that are less advanced and still have unstable national governments and an overreliance on agricultural production. This section shows the patronage system as one that has not only continued over a thousand years, but also one that has the power to continue ad infinitum.Patronage has proven to be a deceptive system. While it no longer has the international power it once did, it has quietly remained a system that controls the lives of many people. It is this ability to quietly adapt that has allowed patronage to stay long after many thought it ended

SHOULDER INSTABILITY

Shoulder instability, particularly of the glenohumeral joint, is common in nowadays medicine, ranging from minor subluxations to complete dislocations caused by trauma or hereditary factors. Anterior dislocations are the most prevalent, often necessitating surgical intervention for associated Bankart lesions. The incidence of traumatic shoulder instability is 1.7% in the general population, with significant recurrence rates. Multidirectional instability (MDI) is notable in patients with hypermobility conditions, increasing the risk of recurrent instability. The shoulder's stability depends on its complex anatomy, including ligaments, muscles, and neurovascular structures. The Stanmore Instability Classification helps categorize instability into structural and non-structural types. Imaging techniques such as MRI and MR arthrography are crucial for diagnosing ligamentous and labral injuries, but they are also essential for planning surgical repairs. Treatment involves both conservative rehabilitations, focusing on muscle strengthening and proprioception, and surgical interventions like Bankart repair and capsular shift, depending on the instability's type and severity. Effective management requires a comprehensive understanding of the shoulder's anatomy, accurate diagnosis, and individualized treatment plans to restore function and prevent recurrence. It is important to note that each patient must be viewed as an individual. Every information given in this thesis is retrospective statistics. The appropriate treatment and care must be provided for each patient individually