Individuals engaged in street prostitution constitute one of the most precarious sectors of modern societies (Mac and Smith, 2018), where migrant women face increased difficulties related to their ...vulnerable position, resulting from the overlay of multiple categories of oppression to which they are subjected (Oliveira, 2011). In countries where sex work either lacks regulation or is not completely decriminalised – as is the case of Portugal –, these women must face obstacles to their admittance to full citizenship (Alvim, 2013). The purpose of this research was to examine a better understanding of the social reality of Lisbon’s street prostitutes, through an ethnographic field work project where individual perceptions about their living and working standards where questioned, taking into account the diversity and complexity of their life paths.
Hydroelectricity provides 6% of U.S. electrical power needs, but hydro‐dams block migrations of both anadromous and catadromous fishes. Engineered fishways have been built to facilitate fish ...movements past dams, but many have performed poorly. Dam removal is an effective way of restoring dwindling migratory fish populations by allowing unrestricted pathways to their spawning areas and for the downstream migrations of post‐spawning adults and juveniles. However, hydro‐dam removals result in a loss of electricity production. For the replacement of energy foregone from a dam removal, various alternative energy installations are now feasible. Here, we present a one‐to‐one conceptual replacement of hydropower with photovoltaic (PV) outputs for large and small river systems in Maine. We estimate that the equivalent land area needed to replace 14 hydro‐dams with PV panels in the Kennebec River watershed—producing an annual mean (±SE) of 1,101.7 ± 37.9 gigawatt‐hours—is 950.7 ± 32.8 ha, which is equivalent to 22% of the existing reservoir area. For the Mousam River, three hydro‐dams could be replaced with 0.38 ha of PV. Our results indicate that modest land areas are needed to replace hydroelectricity with PV from even heavily dammed rivers, providing a realistic and potentially highly effective conservation policy option for Maine and for elsewhere.
A total of 16 polycyclic aromatic hydrocarbons (PAHs) were measured in 28 soil column samples from two contaminated industrial sites in Eastern China. The total concentration of 16 PAHs (∑PAHs) in ...the surface soil (0–20 cm) was measured up to 52,600 ng/g (dry weight basis) with a remarkable spatial difference in the studied contaminated sites. The concentrations of the ∑PAHs in soils decreased with the increase in soil depth (0–10 m). The surface and subsurface soil presented a tenfold higher concentration than the soil with depth greater than 4 m. Additionally, the vertical migration tendency of the PAHs was found to be correlated significantly with their hydrophobicity (
R
2
= 0.79,
P
< 0.01). Naphthalene (with lowest octanol–water partition coefficient among the studied PAHs) showed the greatest average soil depth at which its peak concentration occurred. Furthermore, risk quotient analysis by using benzoapyrene as reference compound showed that 71.4% of the samples exhibited high ecological risk for soil. Moreover, the total carcinogenic risk of the PAHs in the surface soil samples was assessed at 5.61 × 10
–5
–1.28 × 10
–4
and 4.41 × 10
–6
–9.43 × 10
–5
for male and female workers, respectively, in which 67.9%–71.4% of the samples showed potential risk. Generally, these results suggest a further consideration of ecological and health risks associated with PAHs in contaminated sites in Eastern China.
Graphical abstract
Abstract In this article we explore universes of circulations, flows and mobilities along two interconnected axes. We propose a reflection on the dynamics of managing bodies and populations in ...transit through categories that regulate journeys and stays, and produce (mal)adaptations. In complementary form, we also question the classificatory processes that pervade the experiences of migrants when they enter distinct regimes of producing difference and are racialized, ethnicized and generified. Our hypothesis is that the connection between these two axes involves the production, at diverse levels, of ‘out of place’ bodies.
Resumo O objetivo do artigo é abordar universos de circulações, fluxos e mobilidades a partir de dois eixos interligados. Por um lado, propomos uma reflexão sobre as dinâmicas de gerenciamento dos corpos e populações em trânsito por meio de categorias que regulam passagens e estadias e produzem (in)adequações. Complementarmente, questionamos os processos classificatórios que perpassam as experiências dos migrantes quando adentram distintos regimes de produção da diferença e são racializados, etnicizados e generificados. Nossa hipótese é a de que a conexão entre os dois eixos abordados se dá pela produção, em diversos níveis, de corpos “fora de lugar”.
To understand hydrocarbon migration in terms of the mechanisms, accumulations and exploration targets, it is essential to correctly identify and characterize the carrier systems that control ...fluid-migration history and oil/gas reservoir formation. The Yinggehai Basin in China is an important area for natural gas exploration and production. However, due to the argillaceous sand sedimentary environment and the absence of faults from the Neogene thermal subsidence period, traditional migration pathways are absent in the Yinggehai Basin, posing significant challenges to target evaluation in this area. Exploration shows that most of the existing gas reservoirs are associated with vertical migration. In this work, coherence cube and curvature seismic techniques are used in the central diapir zone of the Yinggehai Basin to identify diapir-associated fractures and regional stress. Together with geological analysis, two categories of carrier system are discussed in detail to explain the complex migration and accumulation patterns that have puzzled the area. Diapirs have five evolutionary phases, i.e., pressurization, piercing, equilibrium, release and collapse, which have different fracture development patterns, leading to different mechanisms of hydrocarbon migration and accumulation. The carbon isotopes of gaseous hydrocarbons in DF shallow layers and mid-deep layers have an inverted order distribution, indicating mixed accumulation with different maturity, whereas in the mid-deep layers of the diapir-affected areas, there is a single accumulation with low maturity. Early diapiric activity allowed the natural gas produced from deep source rocks to migrate upward along the diapiric carrier system and accumulate in suitable traps to form gas reservoirs. For regional-stress related fractures, the gradual loss of overpressure and fluids from deep to shallow in high-pressure fractures results in the gas accumulation time of deep traps in the regional stress-related carrier system being relatively late and the gas accumulation time of shallow traps being relatively early.
Diel vertical migration (DVM) is the most common behavioral phenomenon in zooplankton, and numerous studies have evaluated DVM under strong seasonality at higher latitudes. Yet, our understanding of ...the environmental drivers of DVM at low latitudes, where seasonal variation is less pronounced, remains limited. Therefore, we here examined patterns of vertical distribution in copepods in six subtropical Bahamian blue holes with different food web structure and tested the role of several key environmental variables potentially affecting this behavior. Day and night samplings showed that copepods generally performed DVM, characterized by downward migration to deeper depths during the day and upward migration to surface waters at night. Across all blue holes, the daytime vertical depth distribution of calanoid copepods correlated positively with both predation risk and depth of food resources (Chlorophyll
a
), but was less affected by ultraviolet radiation (UVR). A potential explanation is that since UVR is a continuous threat across seasons, zooplankton have established photoprotective pigmentation making them less vulnerable to this threat. The copepods also showed a size-structured depth segregation, where larger individuals were found at deeper depths during the day, which further strengthens the suggestion that predation is a major driver of DVM in these systems. Hence, in contrast to studies performed at higher latitudes, we show that despite the constant exposure to UVR, predator avoidance and food availability are the most pronounced drivers of copepod DVM at those low latitudes, suggesting that the main driver of DVM may vary among systems, but also systematically by latitude.
In the last decades, the migration phenomenon has become one of the greatest humanitarian crises. The generalized solution by the international community has been the reception in refugee camps as a ...temporary solution to the displacement. Nonetheless, conflicts are frequently prolonged in time and migrants are stagnated in protracted situations. The objective of this project is to explore alternatives to refugee camps, namely, the reception of migrants in cities. The project is centered around the idea that this strategy will not only be beneficial for the migrants, who will be able to break the dependency built in the camps, but also for the development of the economies of the host countries, by creating more employment, generating a more competitive market, and promoting the development of the infrastructures of the cities. This is going to be studied from the perspective of Ecuador, the country of Latin America that hosts more refugees and migrants, without the establishment of camps.
Survival of post‐larval and juvenile organisms can depend on multiple seasonally‐fluctuating features, including thermal conditions and food availability. Alterations in the phenology of either ...consumers or their prey might decouple trophic relationships and reduce consumer growth and survival, and this potential for mismatches is especially pronounced in migratory organisms that change habitats. Juvenile sockeye salmon (Oncorhynchus nerka) migrate from natal streams to lake habitats, and we hypothesised that their in‐lake growth and survival depends on whether timing of migration matches suitable lake conditions.
We used mixed effects models to test the hypotheses that: (a) the most successful entry times correspond to favourable prey densities and lake thermal conditions; and (b) a mismatch in fish entry time and seasonal lake dynamics can reduce fish growth and survival. These models were applied to an 11‐year time series of migration timing, capture rate and size at smolting for juvenile sockeye salmon in Lake Washington, WA, USA.
Juvenile sockeye salmon entering Lake Washington later in the season encountered higher zooplankton abundance and warmer water, and experienced higher average rates of growth and survival, but the optimal date for lake entry ranged across years by up to a month. Zooplankton abundance and bloom timing affected fish growth and relative survival more than lake temperature, and survival was most influenced by zooplankton abundance in the spring when fish entered the lake. In contrast, fish size at seaward migration from the lake depended primarily on zooplankton abundance in the spring as they left the lake rather than the previous spring when they entered.
These results suggest that maintaining a wide window of lake entry dates allows this population to capture the annually‐varying period of favourable conditions, minimising mismatches between juvenile fish and their resources and thereby enabling successful recruitment in an unpredictable environment.
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