Estimation of general Hamiltonian parameters via controlled energy measurements

The quantum Cram\'er-Rao theorem states that the quantum Fisher information (QFI) bounds the best achievable precision in the estimation of a quantum parameter $\xi$. This is true, however, under the assumption that the measurement employed to extract information on $\xi$ are regular, i.e. neither its sample space nor its positive-operator valued elements depend on the (true) value of the parameter. A better performance may be achieved by relaxing this assumption. In the case of a general Hamiltonian parameter, i.e. when the parameter enters the system's Hamiltonian in a non-linear way (making the energy eigenstates and eigenvalues $\xi$-dependent), a family of non-regular measurements, referred to as controlled energy measurements, is naturally available. We perform an analytic optimization of their performance, which enables us to compare the optimal controlled energy measurement with the optimal Braunstein-Caves measurement based on the symmetric logarithmic derivative. As the former may outperform the latter, the ultimate quantum bounds for general Hamiltonian parameters are different than those for phase (shift) parameters. We also discuss in detail a realistic implementation of controlled energy measurements based on the quantum phase estimation algorithm and work out a variety of examples to illustrate our results.Comment: revised and enlarged versio

The education of girls in the Early 20th century: Aurelia Josz’s educational and didactic experimentation

This paper illustrates the results of historical research on educational experimentation in the field of education of girls. In the early 20th century in Italy the debates on how girls and women were to be educated was very lively. Italy, which had recently been unified, saw for the first time, legislation that established that primary schooling should also be open to young girls and women. Even though the law established compulsory schooling for boys and girls at the time, actually, educational paths accessible to or reserved for girls were extremely limited. Within this framework, the experimentation of Aurelia Josz is interesting and little known: she was a teacher, trainer and writer who founded in 1902 the Women’s Practical School of Agriculture (Scuola Pratica Agraria Femminile). It was a training course for girls who wanted to become professionals in agriculture, breeding, floriculture, gardening. Aurelia Josz carried out a largely innovative experimentation as to curriculum, methodologies, design of spaces and materials. This contribution will analyse Josz’s experimentation and compare it with the contemporary pedagogical debate, starting from the study of the documents present at the Historical Archives of the Società Umanitaria and at the Contemporary Jewish Documentation Centre of Milan.Este artigo ilustra os resultados da pesquisa histórica sobre experimentação educacional no campo da educação de meninas. No início do século 20, na Itália, os debates sobre como meninas e mulheres deveriam ser educadas foi muito animado. A Itália, que havia sido recentemente unificada, viu pela primeira vez uma legislação que estabelecia que a educação primária também deveria ser aberta a meninas e mulheres jovens. Embora a lei estabeleça a escolaridade obrigatória para meninos e meninas na época, na verdade, os caminhos educacionais acessíveis ou reservados para as meninas eram extremamente limitados. Dentro desse quadro, a experimentação de Aurelia Josz é interessante e pouco conhecida: foi professora, formadora e escritora que fundou em 1902 a Escola Prática da Agricultura Feminina (Scuola Pratica Agraria Femminile). Foi um curso de treinamento para meninas que queriam se tornar profissionais em agricultura, criação, floricultura e jardinagem. Aurelia Josz realizou experiências amplamente inovadoras quanto ao currículo, metodologias e design de espaços e materiais. Esta contribuição analisará a experimentação de Josz e a comparará com o debate pedagógico contemporâneo, partindo do estudo dos documentos presentes no Arquivo Histórico da Società Umanitaria e no Centro de Documentação Judaica Contemporânea de Milão

Structural and functional investigation of underexplored carbohydrate-active enzyme families

The known consequences of the current fossil-based economy require a transition towards a bio-based economy. Development of biorefineries in which plant biomass can be utilized as a renewable source of energy and building blocks to produce both commodities and high-value products, is a key step in this transition. Lignocellulosic biomass has, however, evolved a highly complex architecture to be recalcitrant to degradation, and this represents a major challenge in its utilization. In nature, a wide variety of microorganisms has evolved to exploit lignocellulose as carbon source. They produce carbohydrate-active enzymes (CAZymes) to degrade lignocellulose polymers into components that can be utilized for their growth. CAZymes therefore represent powerful tools that could be utilized in industrial settings for the degradation of plant biomass.\ua0In this thesis, I investigated different CAZymes belonging to relatively unexplored families. The aim was to expand our yet limited knowledge and to gain further insights into their physiological roles. Bacterial enzymes belonging to the carbohydrate esterase family 15 (CE15) were identified in putative pectin-targeting polysaccharide utilization loci (PULs) – clusters of co-regulated genes coding for proteins involved in the degradation of specific polysaccharide motifs. These CE15 enzymes showed comparable activities on model substrates mimicking pectin-esters and on canonical model substrates. This result led to study their activity also on extracted pectins and pectin-rich biomass, although no new activities were revealed. X-ray protein crystallography was used to obtain structures of PvCE15, also in complex with the sugar moiety of the model substrates, to gain insight into its likely specificity. A broader selection of CE15 enzymes of both fungal and bacterial origin was characterized on an additional, non-conventional, model substrate to define their substrate specificity in regards of the position of the ester substituents in the targeted bond. Furthermore, one of the first bacterial copper radical oxidases, belonging to an unexplored clade of the Auxiliary Activity family 5 (AA5), was heterologously produced and characterized on a wide range of alcohol substrates. Finally, I determined the structure of a previously characterized AA9 lytic polysaccharide monooxygenase with broad substrate specificity, indicating certain structural features as possible determinants of the described specificity

Mesoscopic pinning forces in neutron star crusts

The crust of a neutron star is thought to be comprised of a lattice of nuclei immersed in a sea of free electrons and neutrons. As the neutrons are superfluid their angular momentum is carried by an array of quantized vortices. These vortices can pin to the nuclear lattice and prevent the neutron superfluid from spinning down, allowing it to store angular momentum which can then be released catastrophically, giving rise to a pulsar glitch. A crucial ingredient for this model is the maximum pinning force that the lattice can exert on the vortices, as this allows us to estimate the angular momentum that can be exchanged during a glitch. In this paper we perform, for the first time, a detailed and quantitative calculation of the pinning force \emph{per unit length} acting on a vortex immersed in the crust and resulting from the mesoscopic vortex-lattice interaction. We consider realistic vortex tensions, allow for displacement of the nuclei and average over all possible orientation of the crystal with respect to the vortex. We find that, as expected, the mesoscopic pinning force becomes weaker for longer vortices and is generally much smaller than previous estimates, based on vortices aligned with the crystal. Nevertheless the forces we obtain still have maximum values of order $f_{\rm{pin}}\approx 10^{15}$ dyn/cm, which would still allow for enough angular momentum to be stored in the crust to explain large Vela glitches, if part of the star is decoupled during the event.Comment: 17 pages, 16 figures, 5 table

Quantum sensing of curvature

We address the problem of sensing the curvature of a manifold by performing measurements on a particle constrained to the manifold itself. In particular, we consider situations where the dynamics of the particle is quantum mechanical and the manifold is a surface embedded in the three-dimensional Euclidean space. We exploit ideas and tools from quantum estimation theory to quantify the amount of information encoded into a state of the particle, and to seek for optimal probing schemes, able to actually extract this information. Explicit results are found for a free probing particle and in the presence of a magnetic field. We also address precision achievable by position measurement, and show that it provides a nearly optimal detection scheme, at least to estimate the radius of a sphere or a cylinder

Los beneficiarios del "Programa de Seguridad Comunitaria" ante los vecinos de la ciudad de San Luis. Una posible reconstrucción de sus miradas

Este trabajo presenta una serie de avances preliminares elaborados sobre una investigación en curso, cuyo propósito es el de indagar sobre la construcción subjetiva de la alteridad en el marco del Programa de Seguridad Comunitaria que es implementado en la ciudad de San Luís. Los protectores, que se desempeñan como centinelas urbanos en cierto barrios de la ciudad, se presentan a la vez como beneficiarios de la política de Estado, situación que ha llevado a una reacción ambivalente entre los vecinos. Marcados por su condición de clase, la sensibilidad colectiva desborda en rasgos polarizados; pinturas del mundo que culpabilizan/ criminalizan por diversas vías a los sujetos o bien los sitúan en el lugar del desamparo y la miserabilidad. Como vía de interpretación posible, planteamos que estas miradas sobre los sujetos se construyen como fragmento de una visión de dispensabilidad, lo cual en el marco de la política estatal hace eco de las condiciones de dominio a las cuales se encuentran sometidos.Fil: Seveso Zanin, Emilio José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones y Estudios Sobre Cultura y Sociedad. Universidad Nacional de Córdoba. Centro de Investigaciones y Estudios Sobre Cultura y Sociedad; Argentin