Homfly polynomials from the hilbert schemes of a planar curve: [after D. Maulik, A. Oblomkov, V. Shende,...]

Among the most interesting invariants one can associate with a link ${\mathcal L} \subset S^3$ is its HOMFLY polynomial $P({\mathcal L},v,s) \in {\mathbb Z}[v^{\pm1}, (s-s^{-1})^{\pm1}].$ A. Oblomkov and V. Shende conjectured that this polynomial can be expressed in algebraic geometric terms when $\mathcal L$ is obtained as the intersection of a plane curve singularity $(C,p) \subset {\mathbb C}^2$ with a small sphere centered at $p$: if $f =0$ is the local equation of $C$, its Hilbert scheme $C_p^{[n]}$ is the algebraic variety whose points are the length $n$ subschemes of $C$ supported at $p$, or, equivalently, the ideals $I \subset {\mathbb C}[[x,y]]$ containing $f$ and such that $\dim {\mathbb C}[[x,y]]/I=n$. If $m: C_p^{[n]} \to {\mathbb Z}$ is the function associating with the ideal $I$ the minimal number $m(I)$ of its generators, they conjecture that the generating function $Z(C,v,s)=\sum_n s^n \int_{C_p^{[n]}}(1-v^2)^{m(I)}d\chi(I)$ coincides, after a renormalization, with $P({\mathcal L},v,s)$. In the formula the integral is done with respect to the Euler characteristic measure . A more refined version of this surprising identity, involving a ``colored" variant of P(L,v,s), was conjectured to hold by E. Diaconescu, Z. Hua and Y. Soibelman. The seminar will illustrate the techniques used by D. Maulik to prove this conjecture

DEVELOPMENT OF FUNCTIONAL NANOCOMPOSITE MATERIALS TOWARDS BIODEGRADABLE SOFT ROBOTICS AND FLEXIBLE ELECTRONICS

World population is continuously growing, as well as the influence we have on the ecosystem\u2019s natural equilibrium. Moreover, such growth is not homogeneous and it results in an overall increase of older people. Humanity\u2019s activity, growth and aging leads to many challenging issues to address: among them, there are the spread of suddenly and/or chronic diseases, malnutrition, resource pressure and environmental pollution. Research in the novel field of biodegradable soft robotics and electronics can help dealing with these issues. In fact, to face the aging of the population, it is necessary an improvement in rehabilitation technologies, physiological and continuous monitoring, as well as personalized care and therapy. Also in the agricultural sector, an accurate and efficient direct measure of the plants health conditions would be of help especially in the less-developed countries. But since living beings, such as humans and plants, are constituted by soft tissues that continuously change their size and shapes, today\u2019s traditional technologies, based on rigid materials, may not be able to provide an efficient interaction necessary to satisfy these needs: the mechanical mismatch is too prohibitive. Instead, soft robotic systems and devices can be designed to combine active functionalities with soft mechanical properties that can allow them to efficiently and safely interact with soft living tissues. Soft implantable biomedical devices, smart rehabilitation devices and compliant sensors for plants are all applications that can be achieved with soft technologies. The development of sophisticated autonomous soft systems needs the integration on a unique soft body or platform of many functionalities (such as mechanical actuation, energy harvesting, storage and delivery, sensing capabilities). A great research interest is recently arising on this topic, but yet not so many groups are focusing their efforts in the use of natural-derived and biodegradable raw materials. In fact, resource pressure and environmental pollution are becoming more and more critical problems. It should be completely avoided the use of in exhaustion, pollutant, toxic and non-degradable resources, such as lithium, petroleum derivatives, halogenated compounds and organic solvents. So-obtained biodegradable soft systems and devices could then be manufactured in high number and deployed in the environment to fulfil their duties without the need to recover them, since they can safely degrade in the environment. The aim of the current Ph.D. project is the use of natural-derived and biodegradable polymers and substances as building blocks for the development of smart composite materials that could operate as functional elements in a soft robotic system or device. Soft mechanical properties and electronic/ionic conductive properties are here combined together within smart nanocomposite materials. The use of supersonic cluster beam deposition (SCBD) technique enabled the fabrication of cluster-assembled Au electrodes that can partially penetrate into the surface of soft materials, providing an efficient solution to the challenge of coupling conductive metallic layers and soft deformable polymeric substrates. In this work, cellulose derivatives and poly(3-hydroxybutyrate) bioplastic are used as building blocks for the development of both underwater and in-air soft electromechanical actuators that are characterized and tested. A cellulosic matrix is blended with natural-derived ionic liquids to design and manufacture completely biodegradable supercapacitors, extremely interesting energy storage devices. Lastly, ultrathin Au electrodes are here deposited on biodegradable cellulose acetate sheets, in order to develop transparent flexible electronics as well as bidirectional resistive-type strain sensors. The results obtained in this work can be regarded as a preliminary study towards the realization of full natural-derived and biodegradable soft robotic and electronic systems and devices

Ocular hypertension in myopia: analysis of contrast sensitivity

Purpose: we evaluated the evolution of contrast sensitivity reduction in patients affected by ocular hypertension and glaucoma, with low to moderate myopia. We also evaluated the relationship between contrast sensitivity and mean deviation of visual field. Material and methods: 158 patients (316 eyes), aged between 38 and 57 years old, were enrolled and divided into 4 groups: emmetropes, myopes, myopes with ocular hypertension (IOP≥21 ±2 mmHg), myopes with glaucoma. All patients underwent anamnestic and complete eye evaluation, tonometric curves with Goldmann’s applanation tonometer, cup/disc ratio evaluation, gonioscopy by Goldmann’s three-mirrors lens, automated perimetry (Humphrey 30-2 full-threshold test) and contrast sensitivity evaluation by Pelli-Robson charts. A contrast sensitivity under 1,8 Logarithm of the Minimum Angle of Resolution (LogMAR) was considered abnormal. Results: contrast sensitivity was reduced in the group of myopes with ocular hypertension (1,788 LogMAR) and in the group of myopes with glaucoma (1,743 LogMAR), while it was preserved in the group of myopes (2,069 LogMAR) and in the group of emmetropes (1,990 LogMAR). We also found a strong correlation between contrast sensitivity reduction and mean deviation of visual fields in myopes with glaucoma (coefficient relation = 0.86) and in myopes with ocular hypertension (coefficient relation = 0.78). Conclusions: the contrast sensitivity assessment performed by the Pelli-Robson test should be performed in all patients with middle-grade myopia, ocular hypertension and optic disc suspected for glaucoma, as it may be useful in the early diagnosis of the disease. Introduction Contrast can be defined as the ability of the eye to discriminate differences in luminance between the stimulus and the background. The sensitivity to contrast is represented by the inverse of the minimal contrast necessary to make an object visible; the lower the contrast the greater the sensitivity, and the other way around. Contrast sensitivity is a fundamental aspect of vision together with visual acuity: the latter defines the smallest spatial detail that the subject manages to discriminate under optimal conditions, but it only provides information about the size of the stimulus that the eye is capable to perceive; instead, the evaluation of contrast sensitivity provides information not obtainable with only the measurement of visual acuity, as it establishes the minimum difference in luminance that must be present between the stimulus and its background so that the retina is adequately stimulated to perceive the stimulus itself. The clinical methods of examining contrast sensitivity (lattices, luminance gradients, variable-contrast optotypic tables and lowcontrast optotypic tables) relate the two parameters on which the ability to distinctly perceive an object depends, namely the different luminance degree of the two adjacent areas and the spatial frequency, which is linked to the size of the object. The measurement of contrast sensitivity becomes valuable in the diagnosis and follow up of some important eye conditions such as glaucoma. Studies show that contrast sensitivity can be related to data obtained with the visual perimetry, especially with the perimetric damage of the central area and of the optic nerve head

Recomendações para o cultivo da goiabeira no Rio Grande do Sul.

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Recomendações para produção de videiras americanas e híbridas para processamento na região de Pelotas.

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The caregiving experiences of fathers and mothers of children with rare diseases in Italy: Challenges and social support perceptions

Family caregiving is a growing phenomenon with the increased prevalence of chronic illness and shorter hospitalizations. Rare diseases pose significant challenges not only to patients living with these kinds of pathologies but also to those who care for these patients. The caregiving role has specific characteristics. The present work aims to increase knowledge of the challenges that are common or specific to fathers and mothers of children diagnosed with a rare disease. Moreover, the paper analyses the kinds of social support they experience according to gender. A descriptive study was conducted using grounded theory methodology. A semi-structured interview with open-ended questions was conducted with 15 parents of children with a rare disease. The interview was organized into three main areas: personal experiences in caring for a child with a rare disease, family changes and perceived social support. The transcriptions were analyzed using NVivo 11 software. From data analysis, themes emerged regarding the challenges shared by fathers and mothers, but some aspects also emerged that were gender-specific. The analyses of differences between mothers' and fathers' narratives showed that there is a specific experience of the impact that caregiving has on parents' relationships with their jobs and on their worries. Self-help group is the main source of social support for all respondents. We discuss these findings in relation to possible appropriate specific interventions and support for family caregiving

How could self-determination theory be useful for facing health innovation challenges?

This paper offers a presentation of the characteristics of self-determination theory (SDT) in the health context as well as attempts to identify how this theory could be useful for facing health innovation challenges. Health innovation is based on scientific advances that have more complex relationships with health. This paper encourages the use of the SDT approach to face health innovation, both for physiological and pathological processes. In particular, the focus is on the changes and lifestyle choices related to physiological pregnancy and birth and to oncological genetic tests in the Italian context. The health innovation paradigm focuses on patients taking responsibility for making important health-related choices, and we think that SDT can offer new stimuli in light of the changes implemented from innovations in the field of health. The aim is that this manuscript will stimulate researchers to test the potential of this theory in the field of changing health-related processes. Practitioners are called upon to revise their orientation toward patients and, according to SDT, they should support autonomy rather than control the promotion of health-related change

A support theorem for the Hitchin fibration: the case of GLnGL_n and KCK_C

We compute the supports of the perverse cohomology sheaves of the Hitchin fibration for $GL_n$ over the locus of reduced spectral curves. In contrast to the case of meromorphic Higgs fields we find additional supports at the loci of reducible spectral curves. Their contribution to the global cohomology is governed by a finite twist of Hitchin fibrations for Levi subgroups. The corresponding summands give non-trivial contributions to the cohomology of the moduli spaces for every $n \geq 3$. A key ingredient is a restriction result for intersection cohomology sheaves that allows us to compare the fibration to the one defined over the versal deformations of spectral curves