Strong effect of the cluster environment on the size of protoplanetary discs?

Context. Most stars are born in clusters, thus the protoplanetary discs surrounding the newly formed stars might be influenced by this environment. Isolated star-disc encounters have previously been studied, and it was shown that very close encounters are necessary to completely destroy discs. However, relatively distant encounters are still able to change the disc size considerably. Aims. We quantify the importance of disc-size reduction that is due to stellar encounters in an entire stellar population. Methods. We modelled young, massive clusters of different densities using the code Nbody6 to determine the statistics of stellar encounter parameters. In a second step, we used these parameters to investigate the effect of the environments on the disc size. For this purpose, we performed a numerical experiment with an artificial initial disc size of 105 AU. Results. We quantify to which degree the disc size is more sensitive to the cluster environment than to the disc mass or frequency. We show that in all investigated clusters a large portion of discs is significantly reduced in size. After 5 Myr, the fraction of discs smaller than 1000 AU in ONC-like clusters with an average number density of 60pc$^3$, the fraction of discs smaller than 1000 AU is 65%, while discs smaller than 100 AU make up 15%. These fractions increase to 84% and 39% for discs in denser clusters like IC 348 (500pc$^3$). Even in clusters with a density four times lower than in the ONC (15pc$^3$), about 43% of all discs are reduced to sizes below 1 000 AU and roughly 9% to sizes below 100 AU. Conclusions. For any disc in the ONC that initially was larger than 1 000 AU, the probability to be truncated to smaller disc sizes as a result of stellar encounters is quite high. Thus, among other effects, encounters are important in shaping discs and potentially forming planetary systems in stellar clusters.Comment: accepted for publication in A&

Fashion\u27s Destruction of Unsold Goods: Responsible Solutions for an Environmentally Conscious Future

Over the past two years, headlines of fast-fashion and luxury brands burning their merchandise have flooded media outlets. While this came as a shock to the general public, it has actually been a standard industry practice for decades. As societal norms are leaning more towards environmentally conscious practices, destroying unsold products is no longer viewed as an acceptable option. Brands are facing increased scrutiny related to their environmental impact—such as the amount of textile waste that ends up in a landfill—and how they address the issue. While the media have criticized brands for these practices, they have not suggested long-term solutions to resolve the problem. Brands are left in the dark without a road map showing them how to modernize their systems. Furthermore, when governments introduce new bills focused on textile waste, brands experience added pressure. France is in the process of requiring brands to recycle or reuse their unsold goods by January 2020. However, there is no one-size-fits-all solution for any brand or country: what may work for a fast-fashion brand will not necessarily work for a luxury brand. In the same vein, what may work for France may not work for the United States. This Note explores a number of potential solutions to this problem which range from legal solutions, to reusing, manufacturing, technological, and crisis management solutions. Brands must start to address this issue within their supply chain in a thorough and transparent manner, as this is not a fleeting trend

The relation between bar formation, galaxy luminosity, and environment

We derive the bar fraction in three different environments ranging from the field to Virgo and Coma clusters, covering an unprecedentedly large range of galaxy luminosities (or, equivalently, stellar masses). We confirm that the fraction of barred galaxies strongly depends on galaxy luminosity. We also show that the difference between the bar fraction distributions as a function of galaxy luminosity (and mass) in the field and Coma cluster are statistically significant, with Virgo being an intermediate case. We interpret this result as a variation of the effect of environment on bar formation depending on galaxy luminosity. We speculate that brighter disk galaxies are stable enough against interactions to keep their cold structure, thus, the interactions are able to trigger bar formation. For fainter galaxies the interactions become strong enough to heat up the disks inhibiting bar formation and even destroying the disks. Finally, we point out that the controversy regarding whether the bar fraction depends on environment could be resolved by taking into account the different luminosity ranges of the galaxy samples studied so far.Comment: 4 pages, 2 figures. To appear in the proceedings of EWASS 2012 Special Session 4, Structure of galaxy disks shaped by secular evolution and environmental processes, ed. P. Di Matteo and C. Jog, Memorie della Societ\`a Astronomica Italiana Supplement Serie

Penetration and effectiveness of micronized copper in refractory wood species

The North American wood decking market mostly relies on easily treatable Southern yellow pine (SYP), which is being impregnated with micronized copper (MC) wood preservatives since 2006. These formulations are composed of copper (Cu) carbonate particles (CuCO3 center dot Cu(OH)(2)), with sizes ranging from 1 nm to 250 mu m, according to manufacturers. MC-treated SYP wood is protected against decay by solubilized Cu2+ ions and unreacted CuCO3 center dot Cu(OH)(2) particles that successively release Cu2+ ions (reservoir effect). The wood species used for the European wood decking market differ from the North American SYP. One of the most common species is Norway spruce wood, which is poorly treatable i.e. refractory due to the anatomical properties, like pore size and structure, and chemical composition, like pit membrane components or presence of wood extractives. Therefore, MC formulations may not suitable for refractory wood species common in the European market, despite their good performance in SYP. We evaluated the penetration effectiveness of MC azole (MCA) in easily treatable Scots pine and in refractory Norway spruce wood. We assessed the effectiveness against the Cu-tolerant wood-destroying fungus Rhodonia placenta. Our findings show that MCA cannot easily penetrate refractory wood species and could not confirm the presence of a reservoir effect

Technological discontinuities, outsiders and social capital: a case study from Formula 1

Purpose – The purpose of this paper is to examine how and why outsiders, rather than incumbents, are able to take advantage of technological discontinuities. Design/ methodology/approach – The paper employs a case study of a single innovation that transformed the technology of Formula 1 motor racing. Findings – The findings show how social capital made up of ‘weak ties’ in the form of informal personal networks, enabled an outsider to successfully make the leap to a new technological regime. Practical implications – The findings show that where new product development involves a shift to new technologies, social capital can have an important part to play. Originality/value – It is widely accepted that radical innovations are often competence destroying, making it difficult for incumbents to make the transition to a new technology. The findings show how the social capital of outsiders can place them at a particular advantage in utilizing new technologies

Are the 'weak measurements' really measurements?

Weak measurements can be seen as an attempt at answering the 'Which way?' question without destroying interference between the pathways involved. Unusual mean values obtained in such measurements represent the response of a quantum system to this 'forbidden' question, in which the 'true' composition of virtual pathways is hidden from the observer. Such values indicate a failure of a measurement where the uncertainty principle says it must fail, rather than provide an additional insight into physical reality

La desurbanización y el derecho a la ciudad desurbanizada

Cities are historically created as a collaborative work of different generations and derive from the possibilities created bylocal and climatic conditions, social relations and culture. Today, urbanization may appear as a way of organizing everyday hierarchical, exclusive, discriminatory and exploitative life through industrialized mass production of temporary, privatized, homogenized, fragmented, and power-oriented spaces. This mind-set and application generates several social and ecological problems. This article discusses the right to the city concept, and links it to the deurbanization approach as a social and ecological answer to the problems associated with current urban development. The methodology is supported by a review of the literature and an analysis of examples of works created in the De-Urban Design Studio. Results indicate that the deurbanization approach envisions creating resilient, equitable, non-hierarchical cities composed of communities that replace consumption via harmony with nature, that replace individualism and competition viacollaboration and solidarity, and that replace hegemonic relations via an equitable distribution of powerLas ciudades se crean históricamente como un trabajo colaborativo de diferentes generaciones y derivan de las posibilidades de las condiciones locales y climáticas, las relaciones sociales y la cultura. Hoy en día, la urbanización puede aparecer como una forma de organizar la vida cotidiana jerárquica, exclusiva, discriminativa y explotadora a través de la producción en masa industrializada de espacios temporales, privatizados, homogeneizados, fragmentados y orientados hacia el poder. Esta mentalidad y aplicación genera varios problemas sociales y ecológicos. Este artículo pretende discutir el concepto de derecho a la ciudad y vincularlo con el enfoque de desurbanización como una respuesta social y ecológica a los problemas de la urbanización actual. La metodología se apoya en la revisión de la literatura y el análisis de ejemplos de los trabajos creados en De-UrbanDesign Studio.Los resultados indican que el enfoque de desurbanización prevé crear ciudades resilientes, equitativas y no jerárquicas, compuestas por comunidades que reemplazan el consumo por la creación en armonía con la naturaleza; que reemplazan el individualismo y la competencia por la colaboración y la solidaridad y que reemplazan las relaciones hegemónicas por la distribución equitativa del poder

Tear Down This Wall?: The Destruction of Sanctioned Street Art Under U.S. and Italian Law

The United States and Italy are important countries for art and artists, including “street art”—also known as “aerosol art.” How does the law treat street artists in the two countries? Specifically, what are the legal consequences if an artist creates aerosol art on a wall or building with the property owner’s permission, and the property owner tears down the wall or building, thus destroying the artwork? In the United States, the 2018 decision in the 5Pointz case provided a detailed analysis of the applicable law; the court found in favor of a group of aerosol artists against the property owner. How would the same situation be adjudicated in Italy? Which party’s interests would be protected? It appears that, even though works of street art are generally copyrightable in Italy, the conflict between property owners and street artists would most likely be resolved in favor of the property owner. The authors recommend that Italy enact a statute affirmatively protecting sanctioned street art