Arrival or Transient Spaces? Differentiated Politics of Mobilities, Socio-Technological Orderings and Migrants' Socio-Spatial Embeddedness

For the last decade there has been a lively debate on urban arrival spaces. Saunders’ (2011) widely received book Arrival Cities can be seen as catalyst of this debate. Taking a hitherto largely unexplored comparative approach, based on two empirical research studies on migrant workers and highly-skilled migrants in Singapore, this study debates the notion of arrival cities and spaces and argues for a differentiated perspective on the complex and interdependent processes of spatially and socially arriving. By comparing how the politics of mobilities, migration management and differential inclusion influence the migration trajectories of workers and professionals we argue that the concept of transient spaces might be a more fruitful approach for understanding the differentiated processes of arriving and (not) becoming socio-spatially embedded. In order to educe the relevance of a processual perspective, and for a systematic comparison, we apply four analytical dimensions that shed light on the process of migrating, arriving, and passing through. These four dimensions comprise (1) arriving, (2) settling, (3) mingling locally and translocally, and (4) planning ahead for future mobilities. We argue that the scholarship on politics of mobilities needs to take note of the combined effects of states’ and companies’ neoliberal politics of mobility throughout the migration process, and of the increasing relevance of socio-technological orderings, which imprint migrants’ socio-spatial embedding

City-Life No More? Young Adults' Disrupted Urban Experiences and Their Digital Mediation under Covid-19

The Covid-19 pandemic temporarily, yet significantly, reshuffled the position, functions and (mediated) constructions of cities and urban places. The national lockdown, implemented by Austria on 16 March 2020, turned cities overnight from centres of hybrid cultural, economic, social, political life and power to places where urban life(styles) were put on hold. This article begins by presenting first key results of a longitudinal study with young adults studying in educational institutions in the state of Tyrol through the harshest country-wide lockdown measures and their gradual withdrawal. We analyse how participants coped with the disruption of their urban lives and lifestyles and the strategies they employed to compensate. We highlight three main insights. First, participants who had originally migrated to the city from their (often rural) hometowns largely returned to join their families. From there, no longer being an object of physical experience, the city became a digitally imagined, constructed and communicated place, reiterating public discourses that condemned the city as a place where lockdown measures were breached, and the virus spread unchecked. Second, where possible and adapted to the affordances of digital media, students shifted their previous lifestyles to digital space as well as created innovative ways of socialising digitally—thus producing alternative digital forms of urban lifestyles and digitally-mediated urban experiences. Third, during the lockdown period, the importance, use intensity as well as a variety of digital media peaked tremendously. This trend, however, was short-lived as yearned-for offline sociability largely returned to the city once measures were relaxed, leaving those in rural homes detached from their urban peers

Benchmarking biochar with activated carbon for immobilizing leachable PAH and heterocyclic PAH in contaminated soils

Remediation of residually contaminated soils remains a widespread problem. Biochar can immobilize polycyclic aromatic hydrocarbons (PAH). However, studies on its ability to immobilize PAH and N, S, and O substituted PAH (hetero-PAH) in real soils, and benchmarking with commercial activated carbon are missing. Here, we compared the ability of pristine biochar (BC), steam-activated biochar (SABC), and commercial activated carbon (AC) to immobilize PAH and hetero-PAH. The three carbons were tested on soils from four different contami-nated sites in Austria. Different amendment rates (w/w) of the carbons were investigated (BC: 1.0, 2.5, and 5%; SABC: 0.5, 1.0, and 2.0%; AC: 1%) in batch experiments to cover meaningful ranges in relation to their per-formance. SABC performed better than AC, removing at least 80% PAH with the lowest application rate of 0.5%, and achieving a complete removal at an application rate of 1.0%. BC performed slightly worse but still acceptable in residually contaminated soils (40 and 100% removal at 1 and 5% amendment, respectively). The ability of BC and SABC to immobilize PAH decreased as the PAH-molar volume increased. PAH with three or more rings were preferentially removed by AC compared to SABC or BC. This can be explained by the difference in pore size distribution of the carbons which could limit the accessibility of PAH and hetero-PAH to reach sorption sites for pi-pi electron donor-acceptor interactions, which drive PAH and hetero-PAH sorption to carbons. Column percolation tests confirmed the results obtained in batch tests, indicating, that decisions for soil remediation can be derived from simpler batch experiments. In soil samples with 1% BC, a reduction of over 90% in the total concentration of PAH in the leached water was observed. Overall, BC and SABC were demonstrated to be valid substitutes for AC for stabilizing residually contaminated soils

Plastics can be used more sustainably in agriculture

Plastics have become an integral component in agricultural production as mulch films, nets, storage bins and in many other applications, but their widespread use has led to the accumulation of large quantities in soils. Rational use and reduction, collection, reuse, and innovative recycling are key measures to curb plastic pollution from agriculture. Plastics that cannot be collected after use must be biodegradable in an environmentally benign manner. Harmful plastic additives must be replaced with safer alternatives to reduce toxicity burdens and included in the ongoing negotiations surrounding the United Nations Plastics Treaty. Although full substitution of plastics is currently not possible without increasing the overall environmental footprint and jeopardizing food security, alternatives with smaller environmental impacts should be used and endorsed within a clear socio-economic framework. Better monitoring and reporting, technical innovation, education and training, and social and economic incentives are imperative to promote more sustainable use of plastics in agriculture

Are We Speaking the Same Language? Recommendations for a Definition and Categorization Framework for Plastic Debris

The accumulation of plastic litter in natural environments is a global issue. Concerns over potential negative impacts on the economy, wildlife, and human health provide strong incentives for improving the sustainable use of plastics. Despite the many voices raised on the issue, we lack a consensus on how to define and categorize plastic debris. This is evident for microplastics, where inconsistent size classes are used and where the materials to be included are under debate. While this is inherent in an emerging research field, an ambiguous terminology results in confusion and miscommunication that may compromise progress in research and mitigation measures. Therefore, we need to be explicit on what exactly we consider plastic debris. Thus, we critically discuss the advantages and disadvantages of a unified terminology, propose a definition and categorization framework, and highlight areas of uncertainty. Going beyond size classes, our framework includes physicochemical properties (polymer composition, solid state, solubility) as defining criteria and size, shape, color, and origin as classifiers for categorization. Acknowledging the rapid evolution of our knowledge on plastic pollution, our framework will promote consensus building within the scientific and regulatory community based on a solid scientific foundation

Microplastics as Vectors for Environmental Contaminants : Exploring Sorption, Desorption, and Transfer to Biota

The occurrence and effects of microplastics (MPs) in the aquatic environment are receiving increasing attention. In addition to their possible direct adverse effects on biota, the potential role of MPs as vectors for hydrophobic organic chemicals (HOCs), compared to natural pathways, is a topic of much debate. It is evident, however, that temporal and spatial variations of MP occurrence do (and will) occur. To further improve the estimations of the role of MPs as vectors for HOC transfer into biota under varying MP concentrations and environmental conditions, it is important to identify and understand the governing processes. Here, we explore HOC sorption to and desorption from MPs and the underlying principles for their interactions. We discuss intrinsic and extrinsic parameters influencing these processes and focus on the importance of the exposure route for diffusive mass transfer. Also, we outline research needed to fill knowledge gaps and improve model-based calculations of MP-facilitated HOC transfer in the environment. Integr Environ Assess Manag 2017;13:488–493. © 2017 SETA

Kohlenwasserstoffverbrückte Komplexe, XXX

Hydrocarbon-Bridged Complexes, XXX. - Nucleophilic Addition of Carbonylmetallates to Cationic Vinyl, Diene, Dienyl and Triene Complexes of Iron, Ruthenium and Cobalt: Di-, Tri-, Tetra- and Pentametallic Complexes with ,- and ,-Hydrocarbon Bridges[Note ][Herrn Professor Ekkehard Lindner zum 60. Geburtstag gewidmet.] The reactions of [Re(CO)5]-, [Ru(CO)2Cp]-, and [Os(CO)4]2- with [Cp2(OC)2Fe2(-CO)(-1:2-CH=CH2)]+, [Cp*Ru(2:4-1,3,7-octatriene)]+, [(OC)Fe(4-diene)(5-cycloheptadienyl)]+, and [CpCo(5-cyclodienyl)]+ give the nucleophilic adducts whereas with [Mn(CO)5]-, [W(CO)3Cp]-, and [Fe(CO)2Cp]- formation of the corresponding C-C coupling products and of the metal-metal-bonded dimers is observed. The structures of Cp*Ru(-1:2:3-1,5-octadienyl)Re(CO)5 (4), [Cp* Ru(-1:2:3-1,5-octadienyl)]2Os(CO)4 (6), and of (OC)-Fe(4-1,3-cyclohexadiene) (-1:4-1,3-cycloheptadiene)Re(CO)5 (9) have been determined by X-ray diffraction

Are We Speaking the Same Language? Recommendations for a Definition and Categorization Framework for Plastic Debris

Embargo until 04 Jan 2020The accumulation of plastic litter in natural environments is a global issue. Concerns over potential negative impacts on the economy, wildlife, and human health provide strong incentives for improving the sustainable use of plastics. Despite the many voices raised on the issue, we lack a consensus on how to define and categorize plastic debris. This is evident for microplastics, where inconsistent size classes are used and where the materials to be included are under debate. While this is inherent in an emerging research field, an ambiguous terminology results in confusion and miscommunication that may compromise progress in research and mitigation measures. Therefore, we need to be explicit on what exactly we consider plastic debris. Thus, we critically discuss the advantages and disadvantages of a unified terminology, propose a definition and categorization framework, and highlight areas of uncertainty. Going beyond size classes, our framework includes physicochemical properties (polymer composition, solid state, solubility) as defining criteria and size, shape, color, and origin as classifiers for categorization. Acknowledging the rapid evolution of our knowledge on plastic pollution, our framework will promote consensus building within the scientific and regulatory community based on a solid scientific foundation.acceptedVersio