The geospace response to variable inputs from the lower atmosphere:a review of the progress made by Task Group 4 of CAWSES-II

The advent of new satellite missions, ground-based instrumentation networks, and the development of whole atmosphere models over the past decade resulted in a paradigm shift in understanding the variability of geospace, that is, the region of the atmosphere between the stratosphere and several thousand kilometers above ground where atmosphere-ionosphere-magnetosphere interactions occur. It has now been realized that conditions in geospace are linked strongly to terrestrial weather and climate below, contradicting previous textbook knowledge that the space weather of Earth's near space environment is driven by energy injections at high latitudes connected with magnetosphere-ionosphere coupling and solar radiation variation at extreme ultraviolet wavelengths alone. The primary mechanism through which energy and momentum are transferred from the lower atmosphere is through the generation, propagation, and dissipation of atmospheric waves over a wide range of spatial and temporal scales including electrodynamic coupling through dynamo processes and plasma bubble seeding. The main task of Task Group 4 of SCOSTEP's CAWSES-II program, 2009 to 2013, was to study the geospace response to waves generated by meteorological events, their interaction with the mean flow, and their impact on the ionosphere and their relation to competing thermospheric disturbances generated by energy inputs from above, such as auroral processes at high latitudes. This paper reviews the progress made during the CAWSES-II time period, emphasizing the role of gravity waves, planetary waves and tides, and their ionospheric impacts. Specific campaign contributions from Task Group 4 are highlighted, and future research directions are discussed

Synthetic and mechanistic studies of polyazole Cyclopeptide natural products: Aurantizolicin and Urukthapelstatin A

This PhD thesis describes the development of an effective total synthesis of the strongly cytotoxic polyazole cyclopeptide natural product aurantizolicin. The synthesis design combined building block synthesis in solution with solid-phase peptide synthesis to enable the rapid diversification of the natural product. Macrothiolactonization and aza-Wittig chemistry allowed the formation of the macrocyclically embedded thiazole. Thereby, the stereochemical assignment of the natural product and the formation of an extensive library of analogs have been achieved. Profiling the analog library for its growth inhibitory effect on human cancer cells revealed crucial structural features and significantly expanded the knowledge of the structure–activity relationships (SAR) of this natural product class. Based on the SAR, chemical probes have been designed and synthesized to enable further investigations towards the elucidation of the mechanism of action of aurantizolicin. These probes included cyclopeptide–dye conjugates, compounds for photoaffinity labeling, and immobilized cyclopeptides. Initial investigations utilizing the immobilized cyclopeptides in compound-centric chemical proteomics experiments suggested an RNA-associated mechanism of action. Beyond natural product chemistry, 5-sulfamoyloxy-oxazoles have been developed as competent C–O electrophiles for Suzuki–Miyaura cross-coupling reactions as well as for aromatic nucleophilic substitutions/conjugate additions of various heteroatom nucleophiles. The reactivity of peptide-integrated oxazolyl-sulfamates has been profiled to allow the divergent synthesis of oxazolyl-arenes, 5-amino-oxazoles, oxazolyl-sulfides, and oxazolyl-aryl ethers. The relevance of the organic synthesis method has been demonstrated by the total synthesis of the natural product almazole D

Leveraging the Cloud for Software Security Services.

This thesis seeks to leverage the advances in cloud computing in order to address modern security threats, allowing for completely novel architectures that provide dramatic improvements and asymmetric gains beyond what is possible using current approaches. Indeed, many of the critical security problems facing the Internet and its users are inadequately addressed by current security technologies. Current security measures often are deployed in an exclusively network-based or host-based model, limiting their efficacy against modern threats. However, recent advancements in the past decade in cloud computing and high-speed networking have ushered in a new era of software services. Software services that were previously deployed on-premise in organizations and enterprises are now being outsourced to the cloud, leading to fundamentally new models in how software services are sold, consumed, and managed. This thesis focuses on how novel software security services can be deployed that leverage the cloud to scale elegantly in their capabilities, performance, and management. First, we introduce a novel architecture for malware detection in the cloud. Next, we propose a cloud service to protect modern mobile devices, an ever-increasing target for malicious attackers. Then, we discuss and demonstrate the ability for attackers to leverage the same benefits of cloud-centric services for malicious purposes. Next, we present new techniques for the large-scale analysis and classification of malicious software. Lastly, to demonstrate the benefits of cloud-centric architectures outside the realm of malicious software, we present a threshold signature scheme that leverages the cloud for robustness and resiliency.PhDComputer Science & EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/91385/1/jonojono_1.pd

The mesospheric inversion layer and sprites

The vertical structure of temperature observed by SABER (Sounding of Atmosphere using Broadband Emission Radiometry) aboard TIMED (Thermosphere, Ionosphere, Mesosphere Energetics and Dynamics) and sprites observations made during the Eurosprite 2003 to 2007 observational campaign were analyzed. Sprite observations were made at two locations in France, namely Puy de Dome in the French Massif Central and at the Pic du Midi in the French Pyrenees. It is observed that the vertical structure of temperature shows evidence for a Mesospheric Inversion Layer (MIL) on those days on which sprites were observed. A few events are also reported in which sprites were not recorded, although there is evidence of a MIL in the vertical structure of the temperature. It is proposed that breaking gravity waves produced by convective thunderstorms facilitate the production of (a) sprites by modulating the neutral air-density and (b) MILs via the deposition of energy. The same proposition has been used to explain observations of lightings as well as both MILs and lightning arising out of deep convections.Comment: 34 pages, 5figures. Accepted in Journal of Geophysical Research, US

El Impacto del Pacto Global de las Naciones Unidas en la Responsabilidad Social Empresarial de la Industria Chilena del Litio

Whereas in the last century public problem-solving took place almost exclusively in intergovernmental forums, in recent decades the locus of control has shifted towards multi-actor participation in global governance. In this context, the private sector is increasingly seen not only as part of the problem, but also as part of the solution. To harness its reach, expertise and transformative power, various international organisations, including the United Nations, are shifting to promote global public-private partnerships. In this context, the United Nations Global Compact (UNGC) has become the largest global framework for sustainability promoting Corporate Social Responsibility (CSR). A current aspect of sustainable change is the decarbonisation of global societies to mitigate climate change. To facilitate this endeavour, the global demand for battery technology increases, which highlights the important and sensitive role of the lithium sector, especially in terms of social and environmental factors. Therefore, this case study explores the impact of the UNGC on CSR development in the Chilean lithium sector by looking at three different perspectives: The UNGC as a learning network and its influence on operational as well as governance aspects of CSR. The findings of the case study underscore the importance of the UNGC in creating protected spaces that enable mutual learning and the exchange of good practices. However, an important prerequisite for the effectiveness of the UNGC is an active participation of member organisations. As the Chilean lithium industry has only recently joined the UNGC, its current role consists in sharing knowledge with other actors, while its own participation in programmes is rather low. Nevertheless, this case study highlights the importance of a collaborative approach, thus calling for the exploitation of synergies between organisations facing similar CSR-related issues to integrate sustainability into core business strategy in line with the global hypernorms driven by the UNGC.Mientras que en el siglo pasado la resolución de problemas públicos tenía lugar casi exclusivamente en foros intergubernamentales, en las últimas décadas el locus de control se ha desplazado hacia la participación de múltiples actores en la gobernanza global. Así, el sector privado se considera no sólo parte del problema, sino también de la solución. Para aprovechar sus contribuciones, las Naciones Unidas están promoviendo asociaciones público-privadas a escala mundial. En este contexto, el Pacto Global de las Naciones Unidas (UNGC) se convirtió en el mayor marco mundial de sostenibilidad que promueve la Responsabilidad Social Empresarial (RSE). Un aspecto actual del cambio sostenible es la descarbonización de las sociedades mitigando el cambio climático, que tiene como consecuencia el aumento en la demanda global de tecnología de baterías, destacando el delicado papel del sector del litio, especialmente en relación con factores sociales y medioambientales. Por lo tanto, este estudio de caso explora el impacto del UNGC en el desarrollo de RSE en el sector chileno del litio desde tres perspectivas diferentes: El UNGC como red de aprendizaje y su influencia en los aspectos operativos y de gobernanza de la RSE. Las conclusiones subrayan la importancia del UNGC en la creación de espacios protegidos que permitan aprendizajes mutuos de buenas prácticas. Sin embargo, un requisito importante para la eficacia del UNGC es la participación activa de las organizaciones miembros. Dado que la industria chilena del litio se ha incorporado recientemente al UNGC, su papel actual consiste en compartir conocimientos con otros actores, mientras que su propia participación en los programas es escasa. No obstante, este estudio de caso demuestra la importancia de un enfoque colaborativo, por lo que, aboga por el aprovechamiento de sinergias para integrar la sostenibilidad en la estrategia empresarial, en consonancia con las hipernormas globales impulsadas por el UNGC

Industrial relations dynamics and gender dynamics : a comparative study on the effectiveness of workplace unions in advocating for work-life balance and gender equality in Germany and Chile

Despite challenges, workplace unions play a crucial role in advocating for progress in Work-Life Balance (WLB) and gender equality, leveraging opportunity structures to renew their bargaining agendas. This thesis examines union effectiveness by exploring how two sets of factors, IR dynamics (representation support, topic involvement, management relations, union experience) and gender dynamics (feminization of organization, feminization of union, gender of the union's president), influence unions' contributions to organizational progress in WLB and gender equality. Considering the lack of comparisons between Chile and Germany given their distinct IR regimes, this study aims to bridge this gap through a cross-case synthesis technique and binary logistic regressions. The empirical findings present mixed results, revealing no universal conclusion regarding the applicability of IR and gender dynamics. While core IR aspects in Germany and Chile empower unions to advocate for WLB, promoting gender equality demands a more nuanced approach. In Germany, effective union advocacy for gender equality relies on reliable management support, experience, and organizational feminization. Conversely, Chilean unions benefit from a facilitative relationship with management and a broader focus on contemporary topics like WLB. Thus, union effectiveness varies by country, underscoring the complexity to tailor union strategies to the unique national and issuebased contexts.Versión original del auto

Loss of the Na(+)/H(+) exchanger NHE8 causes male infertility in mice by disrupting acrosome formation

Mammalian sperm feature a specialized secretory organelle on the anterior part of the sperm nucleus, the acrosome, which is essential for male fertility. It is formed by a fusion of Golgi-derived vesicles. We show here that the predominantly Golgi-resident Na+/H+ exchanger NHE8 localizes to the developing acrosome of spermatids. Similar to wild-type mice, Nhe8-/- mice generated Golgi-derived vesicles positive for acrosomal markers and attached to nuclei, but these vesicles failed to form large acrosomal granules and the acrosomal cap. Spermatozoa from Nhe8-/- mice completely lacked acrosomes, were round-headed, exhibited abnormal mitochondrial distribution and displayed decreased motility, resulting in selective male infertility. Of note, similar features are also found in globozoospermia, one of the causes of male infertility in humans. Germ cell-specific, but not Sertoli cell-specific Nhe8 disruption recapitulated the globozoospermia phenotype, demonstrating that NHE8's role in spermiogenesis is germ cell-intrinsic. Our work has uncovered a crucial role of NHE8 in acrosome biogenesis and suggests that some forms of human globozoospermia might be caused by a loss of function of this Na+/H+ exchanger. It points to NHE8 as a candidate gene for human globozoospermia and a possible drug target for male contraception

Entwicklung eines bildgebenden Verfahrens für die Darstellung biologischen Gewebes basierend auf laserinduziertem Ultraschall

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Divergent Synthesis of C5‐Heteroatom Substituted Oxazoles

5‐Oxazoyl‐sulfamates have been profiled as versatile building blocks for modifications of oxazoles with various nucleophiles. The unified approach provides a diversification platform to directly access 5‐amino‐oxazoles, 5‐oxazolyl‐sulfides, and 5‐oxazoyl‐aryl ethers from a single precursor