Experiences Of Women Leaders In Secondary Education: Negotiating Gender Scripts In An Age Of Accountability

The purpose of this study was to understand the experiences of the women principals. Specifically, the research explored their understanding of gender scripts that exist in the discourse of secondary education and how these women accept, reject, or negotiate scripts in an effort to lead their high schools. A semi-structured interview with each participant allowed for information to be gathered regarding the lived experiences of each participant. Through this research and an analysis of each case, followed by a cross-case analysis, nine themes emerged: 1) expectation to be nurturing; 2) avoidance of appearing too emotional 3) expectations around appearance; 4) higher expectations for women principals; 5) feeling voiceless with male colleagues; 6) expectation to collaborate; 7) lack of credibility: 8) lack of support among faculty and staff and 9) lack of support from female faculty and staff. The findings of this study can be used by principal preparation programs as they work to prepare women principals to work in secondary leadership positions. In addition, the findings may be useful to district leaders as they work to place and support women leaders

Estudio de las propiedades a flexión del cemento con filler de carbonato de calcio

Estudio de la influencia del carbonato cálcico obtenido mediante la precipitación de anhídrido carbónico en la durabilidad, resistencia y ductilidad de la pasta de cemento mediante ensayos de probetas en el laboratorio

Rewiring Chemical Networks Based on Dynamic Dithioacetal and Disulfide Bonds

The control of the connectivity between nodes of synthetic networks is still largely unexplored. To address this point we take advantage of a simple dynamic chemical system with two exchange levels that are mutually connected and can be activated simultaneously or sequentially. Dithioacetals and disulfides can be exchanged simultaneously under UV light in the presence of a sensitizer. Crossover reactions between both exchange processes produce a fully connected chemical network. On the other hand, the use of acid, base or UV light connects different nodes allowing network rewiring.Fil: Orrillo, Alfredo Gastón. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones para el Descubrimiento de Fármacos de Rosario. Universidad Nacional de Rosario. Instituto de Investigaciones para el Descubrimiento de Fármacos de Rosario; ArgentinaFil: la Venia, Agustina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Química Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Química Rosario; ArgentinaFil: Escalante, Andrea Marta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones para el Descubrimiento de Fármacos de Rosario. Universidad Nacional de Rosario. Instituto de Investigaciones para el Descubrimiento de Fármacos de Rosario; ArgentinaFil: Furlan, Ricardo Luis Eugenio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones para el Descubrimiento de Fármacos de Rosario. Universidad Nacional de Rosario. Instituto de Investigaciones para el Descubrimiento de Fármacos de Rosario; Argentin

Therapeutic Radionuclides: Making the Right Choice

Recently, there has been a resurgence of interest in nuclear medicine therapeutic procedures. Using unsealed sources for therapy is not a new concept; it has been around since the beginnings of nuclear medicine. Treatment of thyroid disorders with radioiodine is a classic example. The availability of radionuclides with suitable therapeutic properties for specific applications, as well as methods for their selective targeting to diseased tissue have, however, remained the main obstacles for therapy to assume a more widespread role in nuclear medicine. Nonetheless, a number of new techniques that have recently emerged, (e.g., tumor therapy with radiolabeled monoclonal antibodies, treatment of metastatic bone pain, etc.) appear to have provided a substantial impetus to research on production of new therapeutic radionuclides. Although there are a number of new therapeutic approaches requiring specific radionuclides, only selected broad areas will be used as examples in this article

Disulfide-based dynamic combinatorial libraries of macrocyclic pseudopeptides as bio-inspired complex chemical systems

[cat] Les quimioteques dinàmiques (DCLs de “dynamic combinatorial libraries”) estan formades per una mescla de compostos interconnectats per mitjà de processos químics reversibles. Aquests sistemes dinàmics presenten la capacitat d’adaptar la seva composició a la presència d’un estímul extern. L’objectiu principal d’aquesta tesi és utilitzar DCLs com a sistemes químics complexos pel modelatge experimental de diversos processos d’interès biològic. En el Capítol 1 es van dissenyar, sintetitzar i caracteritzar catorze ditiols amb informació estructural de tipus peptídic, cadenes laterals amb diferents càrregues i informació quiral. A continuació, en el Capítol 2, es van establir unes condicions experimentals adequades per a generar DCLs de disulfurs a partir de l’oxidació dels ditiols sintetitzats. En aquest sentit, l’ús de DMSO com a codissolvent orgànic va demostrar tenir una sèrie d’efectes beneficiosos. Seguidament, en el Capítol 3, es va utilitzar una DCL minimalista de disseny bioinspirat per a reproduir tendències adaptatives pròpies de processos evolutius biològics. Així, es va observar que els canvis que provoca l’increment de la salinitat en la composició d’una DCL de pseudopèptids macrocíclics, tenen una notable similitud amb l’evolució natural de les proteïnes dels microorganismes halòfils. En el Capítol 4 es va estudiar l’efecte del mateix estímul extern en la composició d’una DCL complexa formada per espècies amb diferents càrregues. S’evidencià que el comportament de cada membre de la quimioteca està determinat per la seva informació estructural i per les múltiples relacions coadaptatives que aquest estableix amb la resta de membres de la xarxa molecular. Finalment, en el Capítol 5, es va utilitzar una DCL minimalista formada per espècies estereoisomèriques per estudiar el fenomen d’autoordenació homoquiral.[eng] Dynamic combinatorial chemistry proposes the creation of a library of compounds (dynamic combinatorial library, DCL) inter-connected through reversible chemical processes. The concentrations in a DCL are determined by differences in the free energy between the constituents and, therefore, the variations in the composition of the library contain valuable information about changes in the stability of the members. The adaptive nature of DCLs can be intimately correlated with a very simple expression of molecular evolution. The main objective of this thesis is to use DCLs as bio-inspired complex chemical systems for the minimalistic experimental modeling of different processes of biological interest. In Chapter 1, fourteen new pseudopeptidic dithiols were designed, synthesized and fully characterized in order to be used as bipodal building blocks (BBs). Their design is based on a C2-symmetric scaffold consisting of a central m-phenylenediamine chromophore that rigidly joins two identical arms, each formed by an amino acid with a mercaptoacetyl moiety attached to the N-terminus. The pseudopeptidic nature provides the BBs with peptide-like information, differently charged functional groups and chiral information. In Chapter 2, suitable experimental conditions were developed for the generation of disulfide-based DCLs from the mixture of the synthesized BBs. For this purpose, the use of DMSO as a co-solvent has beneficial effects in the thiol-disulfide dynamic covalent chemistry. Apart from the general gain in the aqueous solubility of the organic molecules, it promotes the thiol oxidation, highly reducing the reaction time for the disulfide formation. Besides, it accelerates the disulfide exchange, allowing the system to fully equilibrate even at slightly acidic pH. In Chapter 3, a minimalistic DCL was used to reproduce adaptive trends described for the evolution of biological systems. Thus, the addition of salt to a dynamic library of macrocyclic pseudopeptides induces the amplification of those species concentrating anionic amino acids, with the Asp derivatives showing a better salt-adaptation than the Glu counterparts. Structural studies suggest a folded conformation for the amplified members and reveal the selection of those species showing a smaller accessible surface area. The adaptive process is driven by the increase of the ionic strength and has a remarkable resemblance with the natural evolution of the proteins of halophilic microorganisms for surviving in hypersaline media. In Chapter 4, the same external stimulus was studied in a larger DCL consisting of 21 differently charged dimeric macrocycles. The salt-induced adaptation of this complex system was characterized in a top-down fashion by the dynamic deconvolution into the minimal components. Additionally, structural studies were performed for selected species. The salt-response of the members of the library can be classified in different families attending to the charges, and the behavior of each member is determined by a combination of its structural information and the co-adaptive relationships with the other members of the complex network. Finally, in Chapter 5, a simple DCL consisting of homo- and heterochiral dimeric pseudopeptides was used to study how the chiral information is transmitted from the molecular to the macromolecular level. A decrease in the polarity of the medium induces a homochiral self-sorting process driven by polar intramolecular interactions. Additionally, the homochiral selectivity also increases with the temperature, indicating a positive entropic contribution. Preliminary NMR experiments suggest significantly different conformations for the homo- and heterochiral species. Overall, the adaptive nature of DCLs, together with a suitable bio-inspired design, have demonstrated to allow the minimalistic experimental modeling of different processes of biological interest such as the natural evolution of the halophilic proteins, the co-adaptive relationships in a complex network and the homochiral self-sorting phenomenon

I\u27m Lending You To Uncle Sammy

https://digitalcommons.library.umaine.edu/mmb-vp-copyright/2319/thumbnail.jp

Goin\u27 South

https://digitalcommons.library.umaine.edu/mmb-vp-copyright/1903/thumbnail.jp

Answer to You are My Sunshine

https://digitalcommons.library.umaine.edu/mmb-vp-copyright/1121/thumbnail.jp

Don\u27t Say Good Bye Little Darling

https://digitalcommons.library.umaine.edu/mmb-vp-copyright/1655/thumbnail.jp

Argonne National Laboratory Reports

A current emphasis in nuclear medicine is to better match the physical lifetime of the radionuclides used in vivo for diagnosis and treatment to the biological lifetime of the diagnostic procedure or to minimize radiation dose to areas other than those to be treated. In many cases the biological lifetime is on the order of minutes. Since the direct production of radionuclides with half lives of minutes requires the user to be near a suitable reactor or accelerator, this study was undertaken to produce short-lived radionuclides indirectly. If a long-lived radionuclide decays into a short-lived radionuclide, quick separation of the daughter activity from the parent enables the user to have a short-lived daughter while freeing him from the constraint of proximity to a cyclotron. Systems where a short-lived daughter is separated from a long-lived parent are called radionuclide generators. Two generator systems were developed for use in nuclear medicine, one in diagnostic work and the other for therapeutic work. The yield and breakthrough characteristics were within the limits required to minimize unnecessary radiation exposure in patients. Two parent radionuclides were produced using the beams available from medium energy cyclotrons. The yield was high enough to produce generators that would be useful in clinical applications