Suchergebnisse

In this dissertation, hydroxyapatite-based and hydroxyapatite with carbon composite materials have been rationally designed, synthesized, characterized and applied to processes of environmental concern, namely wastewater remediation (as sorbents) and electrochemical CO2 reduction reaction, CO2RR (as electrocatalysts). Pristine hydroxyapatite (HAP, Ca10(PO4)6(OH)2) and composite HAP/carbon materials have been synthesized according to a simple wet co-precipitation route. Composition, structure and morphology of samples have been investigated by a plethora of physical-chemical techniques (i.e. ICP/OES elemental analyses, N2 adsorption/desorption isotherms, XRD, TEM (and STEM) imaging, TEM/EDX mapping, transmittance FT-IR and Raman spectroscopies, and XPS). Since adsorption onto materials' surface is crucial in both sorption and catalytic applications, a special attention has been devoted to surface properties, determined by means of zeta potential measurements, gas-solid calorimetric/volumetric titrations, and liquid-solid volumetric titrations, thus assessing the amphoteric nature of HAP-based surfaces. At first, pristine pristine HAP has been studied as sorbent for the remediation of inorganic pollution in wastewater (i.e. heavy metal cations such as Cu(II), Pb(II), Cr(III), Ni(II) and Co(II)). Stirred batch adsorption tests and collection of adsorption isotherms in solutions containing both individual and mixtures of heavy metal cations allowed to quantitatively assess HAP sorption ability. Ad-hoc experiments (i.e. microcalorimetric adsorption isotherms) and physical-chemical investigation of metal-loaded samples shed light on the adsorption mechanisms of several polluting species onto HAP surface. Eco-friendly HAP/carbon composites from renewable resources have been instead applied to the remediation of more complex effluents, where simultaneous organic and inorganic pollution may occur. Thanks to their dual nature, HAP/carbon composites exerted outstanding adsorption performances towards both class of polluting species. Both in the form of pristine HAP and HAP/carbon composites, the sorbents exhibited a strict retention of adsorbed pollutants when undergoing leach testing, therefore ensuring no secondary pollution issues. In an exploratory study, HAP/carbon composites have been also implemented as modifiers in self-standing and mechanically stable electrodes for the electrochemical detection of heavy metal cations traces in waterbodies. Benefitting from the pronounced HAP affinity towards such species, encouraging results have been obtained on the detection of some benchmark pollutants, although the registered limits of detection (ca. one order of magnitude improvement to match legislative requirements) and linearity ranges currently limit HAP/carbon modified electrodes applications. Finally, during a 6-months stay at University of California Irvine (UCI), hosted by Prof. Plamen Atanassov group, HAP has been applied as dopant in CO2RR electrocatalysts. The peculiar ability of HAP amphoteric surface to adsorb and destabilize CO2 (i.e. breakage of its linearity) has been exploited in composite electrocatalysts, composed by copper nanoparticles (active phase) and HAP (dopant), supported on N-doped 3D assembly of graphene nanosheets (3D-GNS, carbonaceous support). When tested in a lab scale CO2 electrolyzer, HAP-doped electrocatalysts displayed a faradic efficiency (FE) towards CO2RR ≥ 80% throughout the whole potential range under investigation, minimizing parasitic Hydrogen Evolution Reaction (HER). Interestingly, HAP doping actually altered CO2RR product distribution: in particular, small quantities of C2+ products were produced under low applied overpotential while at higher voltage formate production was boosted. Product distribution alteration has been rationalized taking into account the ability of HAP acid-basic surface groups to stabilize CO2 reduction intermediate species, directing the the selectivity of electrochemical CO2RR processes. Overall, the present study demonstrates that the unique features of HAP make it a versatile material which may be applied for the protection of the environment at 360 degrees, from water to air remediation, as pristine and/or composite material, as sorbent and/or catalysts' dopant.

The ideal of the cultured warrior is a recurrent theme in premodern Japanese writings. This paper aims to provide a critical analysis of discourses on violence and/in knowledge as synthesized in the motto bunbu nidō 文武二道, the "double path of writing and warring." Recent scholarship on the topic has shown how the bunbu binary changed constantly over time, adapting to the contingencies of each historical juncture. Between the late fifteenth and early sixteenth centuries, the weakening of Ashikaga authority opened the way for regional potentates, whose claim to power often found its legitimating source in this rhetorical weapon. Prescriptive textbooks from those years promote the "civil virtues" (bun) as an indispensable prerequisite for any would-be leader, exhorting him to pursue a variety of interests for the sake of good governance. However, the acquisition of cultural capital from literacy alone was arguably insufficient in an age of discord; thus the need arose to establish tighter control through the exercise of force (bu)—if not materially, at least discursively. As a consequence, contemporary warrior house precepts displayed a growing interest in the military sphere, significantly altering the bunbu equilibrium as it was expounded in previous sources. This paper sheds new light on medieval social representations by comparing the didactic pamphlet Sekyōshō (Mirror of the World) and other texts written by warriors of different provenance and status. In particular, I argue that the recursive trope of bunbu served the purpose of empowering an ever-shifting rule, substantiating warriors' essential traits and justifying their political primacy in inter- and intra-class conflicts. Furthermore, I show how this notion and the varying degrees of its components (bun/bu) spread across social classes and—borrowing Pierre Bourdieu's expression—emerged as a peculiar form of symbolic violence.

BACKGROUND: Individual differences in breast size are a conspicuous feature of variation in human females and have been associated with fecundity and advantage in selection of mates. To identify common variants that are associated with breast size, we conducted a large-scale genotyping association meta-analysis in 7169 women of European descent across three independent sample collections with digital or screen film mammograms. METHODS: The samples consisted of the Swedish KARMA, LIBRO-1 and SASBAC studies genotyped on iCOGS, a custom illumina iSelect genotyping array comprising of 211 155 single nucleotide polymorphisms (SNPs) designed for replication and fine mapping of common and rare variants with relevance to breast, ovary and prostate cancer. Breast size of each subject was ascertained by measuring total breast area (mm(2)) on a mammogram. RESULTS: We confirm genome-wide significant associations at 8p11.23 (rs10086016, p=1.3×10(-14)) and report a new locus at 22q13 (rs5995871, p=3.2×10(-8)). The latter region contains the MKL1 gene, which has been shown to impact endogenous oestrogen receptor α transcriptional activity and is recruited on oestradiol sensitive genes. We also replicated previous genome-wide association study findings for breast size at four other loci. CONCLUSIONS: A new locus at 22q13 may be associated with female breast size. ; KARMA and LIBRO-1 were supported by Märit and Hans Rausings Initiative Against Breast Cancer. SASBAC was supported by funding from the Agency for Science, Technology and Research of Singapore (A*STAR), the US National Institute of Health (NIH) and the Susan G. Komen Breast Cancer Foundation. All three studies are genotyped as part of the Collaborative Oncological Gene-environment Study (COGS), which is supported by the European Community's Seventh Framework Programme under grant agreement 223175 (HEALTH-F2-2009-223175) (COGS). Genotyping of the iCOGS array was funded by the European Union (HEALTH-F2-2009-223175), Cancer Research UK (C1287/A10710), the Canadian Institutes of Health Research (CIHR) for the CIHR Team in Familial Risks of Breast Cancer program and the Ministry of Economic Development, Innovation and Export Trade of Quebec (grant PSR-SIIRI-701). BCAC is funded by Cancer Research UK (C1287/A10118 and C1287/A12014). Combining the GWAS data was supported in part by the US National Institutes of Health (NIH) Cancer Post-Cancer GWAS initiative grant 1 U19 CA 148065-01 (DRIVE, part of the GAME-ON initiative). KC was financed by the Swedish Cancer Society (5128-B07-01PAF). KH was supported by the Swedish Research Council (523-2006-972) and the Swedish E Science Research Centre. This work was also supported, in part, by the Intramural Research Program of the U.S. National Cancer Institute, Department of Health and Human Services, USA. We wish to thank Aki Tuuliainen, Kimberley Sio Kim Chua, Sander Canisius, Grethe I.G. Alnæs, Torben Luders and Lodewyk Wessels for their help in data collection and analysis ; Sí

Ziel dieser Arbeit war es, auf der Grundlage einer theoretischen Analyse des Begriffes "Offener Unterricht" eine Begründung der zunehmenden Notwendigkeit einer Öffnung des Unterrichts, speziell in der Sekundarstufe I, zu erarbeiten. Ausgehend von einer präzisierenden Arbeitsdefinition wurde die Situation im Erdkundeunterricht an Brandenburger Real- und Gesamtschulen empirisch untersucht. Es wurde ein geeigneter Weg der Öffnung von Fachunterricht anhand eines erprobten und ausgewerteten Unterrichtskonzeptes vorgestellt. Der Begriff "Offener Unterricht" spielt seit dem Ende des 19. Jahrhunderts, der Zeit der Reformpädagogik, bis heute eine Rolle in der pädagogischen Diskussion. Auf der Grundlage der mit Beginn der 1980iger Jahre verstärkten Bemühungen, diesen Begriff neu zu bestimmen bzw. zu konkretisieren, wurde in der vorliegenden Arbeit einer Präzisierung des Begriffs "Öffnung von Unterricht" entwickelt, die als Arbeitsdefinition die Grundlage für diese Arbeit bildet. Die Notwendigkeit einer differenzierten und individualisierten Unterrichtsgestaltung für ein produktives Lernen bei Kindern und Jugendlichen führt zu Veränderungen in der organisatorisch-methodischen und inhaltlichen Gestaltung des Unterrichts hin zu mehr Offenheit. Derartige Unterrichtsarrangements sind geprägt von einem größeren Anteil demokratischer Entscheidungsfindungen auf der Grundlage von Kommunikation und Kooperation der am Unterricht Beteiligten. Dabei wird die Verschränkung mit den Begriffen Schlüsselqualifikationen, fächerübergreifendes Arbeiten und neue Medien aufgezeigt. Ausgehend von der These, dass eine schrittweise Öffnung des Unterrichts sowohl mit fast allen Schülern als auch durch jeden Lehrenden unter den Rahmenbedingungen des staatlichen Schulsystems möglich ist, leiteten sich die Fragestellungen der derzeitigen Verwirklichung und der Bedingungen und Möglichkeiten einer Öffnung von Unterricht unter Berücksichtigung der erreichbaren Ziele und Qualifikationen ab. Im Rahmen der empirischen Untersuchung konnte gezeigt werden, dass Erdkundelehrerinnen und -lehrer die Bausteine von offenem Unterricht mit ihren Vorstellungen von einem optimalen Unterricht im Fach Erdkunde assoziieren. Diese weichen von ihrem tatsächlich praktizierten Erdkundeunterricht höchst signifikant ab. Ebenfalls deutlich wurde, dass diese Ergebnisse in keinem deutlichen Zusammenhang zu dem Dienstalter der befragten Lehrkräfte stehen. Entscheidend für die Bereitschaft der Unterrichtenden, ihren Unterricht stärker zu öffnen, ist das Verhältnis von Vorbereitungsaufwand und Unterrichtserfolg. Auf der Grundlage der Untersuchungsergebnisse wurde ein Unterrichtskonzept zur Öffnung von Erdkundeunterricht entworfen und nach der praktischen Erprobung diskutiert. Dabei wurde bestätigt, dass sich die Unterrichtseinheit als ein Praxisbaustein zur Öffnung von Fachunterricht in der Sekundarstufe I eignet. ; The idea of this work was based on the necessity for open instruction, especially in secondary scholls based on theoretical analysis from the concept of "open instruction". For this reason, the situation in instruction in geography in the "Realschule" and "Gesamtschule" was empirical investigation, based on a precise definition of "open intruction". It was possible to show a suitable way for more openness in geography lessons with an experienced concept for geography lessons. The concept of "open instruction" has been of crucial importance in the educational discussion since the end of the 19th centuries, the time of reform-education. At the beginning of the 1980's the idea of open instruction was discussed. This work is based on the unfinished definition discussed at that time. The necessity of subtly differentiated and individual instruction for productive learning by children and young people leads to change in organisation, method and contents of instruction with the goal of more openness. These instructions show more democratic decisions. This is connected with definitions of key-qualifications, inter-disciplinary instruction and new medium. On the thesis, that more openness in instruction is possible step by step with nearly all pupils and every teacher on the conditions of state-owned schoolsystems, result in the question of realization, conditions, opportunitys, destinations and qualifications of more openness in instruction. In the empirical research it was possible to show, that geography teachers associate the parts of open instruction with their own ideas from optimal instruction in geography. These ideas are extremely different than the actual real practise instruction. The results are in no way connected with teachers experience. What is important for the teachers willigness for more openness in instrution is to relationship preparationtime and success of intruction. Based on the results of the elaborate empirical research that was implemented and disscussed in geography lessons, it was possible to show, that the concept of more openness is suitable for instruction in the secondary schools.