The tuition tax credit: The historical battle between public and private schools continues

Parents who feared the power of the state have always sought to establish privately-run schools to safeguard the liberties of their children

Liquid-liquid transition in supercooled silicon determined by first-principles simulation

First principles molecular dynamics simulations reveal a liquid-liquid phase transition in supercooled elemental silicon. Two phases coexist below $T_c\approx 1232K$. The low density phase is nearly tetra-coordinated, with a pseudogap at the Fermi surface, while the high density phase is more highly coordinated and metallic in nature. The transition is observed through the formation of van der Waals loops in pressure-volume isotherms below $T_c$.Comment: 9 pages 4 figure

Selective targeting to glioma with nucleic acid aptamers

The term glioma encompasses brain tumours arising from the glial cells. Malignant glioma are characterised by a rapid growth rate and high capacity for invasive infiltration to surrounding brain tissue, hence diagnosis and treatment is difficult, and patient survival is poor. Aptamers are small molecular ligands composed of short oligonucleotides that bind to a target with high specificity and affinity. They are produced in vitro through a method called systematic evolution of ligands by exponential enrichment (SELEX). The aim of the study was to examine the binding selectivity of DNA aptamers on commercial glial cell lines and primary glioma tissues. RNA aptamers and their DNA homologues (SA44, SA43, SA56) were selected for study which showed strong binding affinity to the target U87MG cells as measured by flow cytometry. SA44 and SA43 showed higher uptake and cytoplasmic localisation in U87MG and 1321N1 glioma cell lines compared to non-cancerous SVGP12 cells and non-glioma MCF-7 and T24 cells as measured by confocal microscopy. The data was confirmed quantitatively by flow cytometry analysis, which showed that the aptamers were able to actively internalise in U87MG and 1321N1 tumorigenic cells compared to the non-cancerous and non-glioma cell types. Histochemistry staining on paraffin embedded, formalin fixed patient tissues revealed that the binding selectivity was found to be significantly higher for only SA43 aptamer (p < 0.05) in glioma tissues (grade I, II, III and IV) compared to the non-cancerous and tissues. Aptamer SA43 also showed cell type selectivity within the tissue. The results indicate that SA43 aptamer can differentiate between glioma and non-cancerous cells and tissues and therefore, show promise for histological diagnosis of glioma and targeted delivery. In the future, targeting tumour cells and tissues through the use of SA43 aptamer will help develop molecular imaging, targeted delivery by reduction of the non-specific toxicity of chemotherapy and selectively directing anti-cancer drugs to tumour cells

Annihilation radiation in cosmic gamma-ray bursts

The pair annihilation radiation in gamma-ray bursts is seen as broad lines with extended hard wings. This radiation is suggested to escape in a collimated beam from magnetic polar regions of neutron stars

Gifts Among Strangers: The Social Organization of Freecycle Giving

The Freecycle Network, with its millions of members gifting objects to strangers, is a stalwart fixture of the increasingly popular sharing economy. Unlike the wildly profitable Airbnb and Uber, the Freecycle Network prohibits profit-making, or even barter, providing an altruism-based alternative to capitalist markets while keeping tons of garbage out of landfills. Why do millions of people give through Freecycle instead of selling, donating, or throwing away items? Utilizing participant observation of two overlapping Freecycle groups and a survey of their members, I investigate motivations for giving and the social norms that guide it. I find that while members of other internet-based groups have been found to exhibit altruism and solidarity, altruism and solidarity in Freecycle appear to be secondary. Instead, green-washed convenience takes precedence as members are motivated to give in order to de-clutter their homes in an environmentally friendly fashion and in a way that can expiate guilt from overconsumption. Embedded in local contexts and governed by powerful cultural expectations based on gift exchange and charitable donation, Freecycle givers create a set of social structures that combine with the organization’s focus on the environment to downplay altruism and elide inequalities

Super-diversity as a Methodological Approach: Re-centering Power and Inequality

Super-diversity as a methodological lens calls for a study of dynamics of new and diversified social groups that moves away from more traditional approaches focused on ethnicity. In examining the potential of super-diversity as a methodological lens, I identify a risk of downplaying the effect of “old” categories of difference that are likely to continue to shape social structures as well as space. I propose a re-centering of power and inequality in the study of super-diversity by situating its study within an urban culturalist approach, with sociological tools borrowed from ethnomethodology and symbolic interactionism. This proposal is illustrated through the analysis of two public spaces in a super-diverse New York neighborhood. I conclude by raising questions about the use of super-diversity discourse in the public and policy spheres

Contexts of Exit in the Migration of Russian Speakers from the Baltic Countries to Ireland

Recently, Ireland has become a major destination for migrants from Estonia, Latvia, and Lithuania. Many of these migrants are members of Russian-speaking minorities leaving a context of restrictive citizenship and language laws and varying degrees of ethnic tension. This paper draws on interviews collected in Ireland to examine the role played by the contexts of exit in decisions to migrate among Russian-speaking minorities from the Baltics. The results suggest that Russian speakers from Estonia migrate because of their experiences as minorities, while those from Latvia and Lithuania migrate to escape low wages and irregular employment. This is so despite equally restrictive language and citizenship laws in Estonia and Latvia. I argue that the effect of state policy as a push factor for minority emigration is mediated by other contextual aspects, such as levels of contact, timbre of ethnic relations, and the degree of intersection between economic stratification and ethnicity

Making Sense of Naturalization: What Citizenship Means to Naturalizing Immigrants in Canada and the USA

Immigrant naturalization is both a barometer of inclusiveness and immigrant incorporation and a mechanism of social reproduction of the nation. This article reports on an interview-based study in suburban Toronto and New Jersey that investigated how immigrants explain their decisions to acquire citizenship. It analyzes respondents’ under- standings of naturalization in light of different theories of citizenship and different dimensions of the concept. The study contributes to the literature by showing how many American immigrants interviewed while going through the naturalization process resisted framing naturalization as identity-changing, situating it instead as a common-sense move following permanent settlement and belonging. In contrast, Canadian respondents were more likely to characterize naturalization as an active process that tied them to a positively valued nation. While immigrant respondents in both countries were interested in voting and travel benefits of citizenship, only American respondents sought the protection that citizenship would afford in an anti-immigrant policy climate. I discuss how naturalization as a tool of civic integration and political empowerment resonates with immigrants’ own understandings of the process and consider the role played by the institutional contexts around naturalization and immigration more generally