Local Topological Obstruction For Divisors

Given a smooth, projective variety $X$ and an effective divisor $D\,\subseteq\, X$, it is well-known that the (topological) obstruction to the deformation of the fundamental class of $D$ as a Hodge class, lies in $H^2(\mathcal{O}_X)$. In this article, we replace $H^2(\mathcal{O}_X)$ by $H^2_D(\mathcal{O}_X)$ and give an analogous topological obstruction theory. We compare the resulting local topological obstruction theory with the geometric obstruction theory (i.e., the obstruction to the deformation of $D$ as an effective Cartier divisor of a first order infinitesimal deformations of $X$). We apply this to study the jumping locus of families of linear systems and the Noether-Lefschetz locus. Finally, we give examples of first order deformations $X_t$ of $X$ for which the cohomology class $[D]$ deforms as a Hodge class but $D$ \emph{does not} lift as an effective Cartier divisor of $X_t$

Criterion for logarithmic connections with prescribed residues

A theorem of Weil and Atiyah says that a holomorphic vector bundle $E$ on a compact Riemann surface $X$ admits a holomorphic connection if and only if the degree of every direct summand of $E$ is zero. Fix a finite subset $S$ of $X$, and fix an endomorphism $A(x)\, \in\, \text{End}(E_x)$ for every $x\, \in\, S$. It is natural to ask when there is a logarithmic connection on $E$ singular over $S$ with residue $A(x)$ at every $x\, \in\, S$. We give a necessary and sufficient condition for it under the assumption that the residues $A(x)$ are rigid

Access to healthcare and alternative health-seeking strategies among undocumented migrants in Denmark

<p>Abstract</p> <p>Background</p> <p>As in many European countries, undocumented migrants in Denmark have restricted access to healthcare. The aim of this study is to describe and analyse undocumented migrants' experiences of access to healthcare, use of alternative health-seeking strategies; and ER nurses' experiences in encounters with undocumented migrants.</p> <p>Methods</p> <p>Qualitative design using semi-structured interviews and observations. The participants included ten undocumented South Asian migrants and eight ER nurses.</p> <p>Results</p> <p>Undocumented migrants reported difficulties accessing healthcare. The barriers to healthcare were: limited medical rights, arbitrariness in healthcare professionals' attitudes, fear of being reported to the police, poor language skills, lack of network with Danish citizens, lack of knowledge about the healthcare system and lack of knowledge about informal networks of healthcare professionals. These barriers induced alternative health-seeking strategies, such as self-medication, contacting doctors in home countries and borrowing health insurance cards from Danish citizens. ER nurses expressed willingness to treat all patients regardless of their migratory status, but also reported challenges in the encounters with undocumented migrants. The challenges for ER nurses were: language barriers, issues of false identification, insecurities about the correct standard procedures and not always being able to provide appropriate care.</p> <p>Conclusions</p> <p>Undocumented migrants face formal and informal barriers to the Danish healthcare system, which lead to alternative health-seeking strategies that may have adverse effects on their health. This study shows the need for policies and guidelines, which in accordance with international human rights law, ensure access to healthcare for undocumented migrants and give clarity to healthcare professionals.</p

Logarithmic connections on principal bundles over a Riemann surface

Let $E_G$ be a holomorphic principal $G$--bundle on a compact connected Riemann surface $X$, where $G$ is a connected reductive complex affine algebraic group. Fix a finite subset $D\, \subset\, X$, and for each $x\,\in\, D$ fix $w_x\, \in\, \text{ad}(E_G)_x$. Let $T$ be a maximal torus in the group of all holomorphic automorphisms of $E_G$. We give a necessary and sufficient condition for the existence of a $T$--invariant logarithmic connection on $E_G$ singular over $D$ such that the residue over each $x\, \in\, D$ is $w_x$. We also give a necessary and sufficient condition for the existence of a logarithmic connection on $E_G$ singular over $D$ such that the residue over each $x\, \in\, D$ is $w_x$, under the assumption that each $w_x$ is $T$--rigid

Do learning by teaching environments with metacognitive support help students develop better learning behaviors

We have developed Teachable Agent environments that use learning by teaching with metacognitive support to help middle school students learn about complex science topics. To demonstrate the effectiveness of this approach, we have run studies that compare three systems where (i) students are taught by an agent, (ii) students teach a computer agent, and (iii) students teach a computer agent and receive metacognitive support while teaching. Students ’ activities on the system, captured in log files, were coded using six primary learning activities. In this paper, we analyze behavior fragments systematically derived from the activity sequences, and identify behaviors that correlate well with high and low student performance. Our results show that students who teach and receive metacognitive support exhibit more of the high performing behaviors than the other two groups

In 'Descent' Proposal: Pathologies of Embodiment in Nietzsche, Kafka, and Foucault

This paper advances the argument that Foucault's notion of 'bodily inscription' can be found in more rudimentary form in the Nietzschean notion of 'bodily descent'- the path qua pathology of 'going under' first outlined by Nietzsche in Thus Spoke Zarathustra. The argument is set within context of the ongoing debate in Foucault studies about whether a non-discursive dimension of the body can be posited or whether the body is always already and inevitably discursive. Following Judith Butler's assessment that there is in Foucault's work the presence of a body outside of signification, the present paper argues that Foucaultian bodily inscription is akin to Nietzschean bodily descent: both are predicated on and depend upon the occluded presence of an inherently 'indecent' or 'undisciplined' body, one that disrupts the discursive economy of subjectivization (assujettissement). Through the detailed reading of an exemplary tale by Franz Kafka ('In the Penal Colony'), we attempt to describe the structural axes or disciplinary matrix that descends and is imposed upon 'undisciplined' or 'indecent' bodies, revealing in so doing the 'indecent' body subject to this descent, the body 'crossed over' and 'crossed out' - 'double crossed' - by these axes, by this matrix. We suggest that it is at the crossroads or the crossing of these axes, precisely at the point where the indecent and untidy body is 'inscribed' and 'disciplined', that Foucault, like Nietzsche, locates a point that points beyond the structure, beyond axial and axiomatic binaries, to a body of inherent possibilities, affective virtualities, and spirited resistance

Laboratory Investigation of Skid Resistance for Steel Slag Utilization as Chip Seal

Slag as waste material of steel-making process has similar characteristics with aggregate that has been widely used in pavement construction. The use of slag as chip seal aggregate to provide skid resistance needs to be analyzed. In this laboratory study, the chip seal samples are made using steel slag and natural aggregate. The bonding materials used are asphalt and epoxy resin. Skid resistance tests for all chip seal samples and also hot rolled sheet pavement without chip seal application are performed using the Portable British Pendulum Tester. The results show the variations of chip seal aggregate weight are inconsistent. The natural aggregate used as chip seal material could produce high skid resistance value of 10.3% higher than that using steel slag. Also the skid resistance of chip seal with the ALD 3 mm are not significantly different with that of ALD 6 mm. Similar results occur on the skid resistance of chip seals using epoxy resin and asphalt

Light and myopia: from epidemiological studies to neurobiological mechanisms

Myopia is far beyond its inconvenience and represents a true, highly prevalent, sight-threatening ocular condition, especially in Asia. Without adequate interventions, the current epidemic of myopia is projected to affect 50% of the world population by 2050, becoming the leading cause of irreversible blindness. Although blurred vision, the predominant symptom of myopia, can be improved by contact lenses, glasses, or refractive surgery, corrected myopia, particularly high myopia, still carries the risk of secondary blinding complications such as glaucoma, myopic maculopathy, and retinal detachment, prompting the need for prevention. Epidemiological studies have reported an association between outdoor time and myopia prevention in children. The protective effect of time spent outdoors could be due to the unique characteristics (intensity, spectral distribution, temporal pattern, etc.) of sunlight that is lacking in artificial lighting. Concomitantly, studies in animal models have highlighted the efficacy of light and its components in delaying or even stopping the development of myopia and endeavoured to elucidate possible mechanisms involved in this process. In this narrative review, we (1) summarize the current knowledge concerning light modulation of ocular growth and refractive error development based on studies in human and animal models, (2) summarize potential neurobiological mechanisms involved in the effects of light on ocular growth and emmetropization and (3) highlight a potential pathway for the translational development of noninvasive light-therapy strategies for myopia prevention in children.info:eu-repo/semantics/publishedVersio