Droplet microactuator system

The present invention relates to a droplet microactuator system. According to one embodiment, the droplet microactuator system includes: (a) a droplet microactuator configured to conduct droplet operations; (b) a magnetic field source arranged to immobilize magnetically responsive beads in a droplet during droplet operations; (c) a sensor configured in a sensing relationship with the droplet microactuator, such that the sensor is capable of sensing a signal from and/or a property of one or more droplets on the droplet microactuator; and (d) one or more processors electronically coupled to the droplet microactuator and programmed to control electrowetting-mediated droplet operations on the droplet actuator and process electronic signals from the sensor

Microplastics and nanoplastics in the marine-atmosphere environment

The discovery of atmospheric micro(nano)plastic transport and ocean-atmosphere exchange points to a highly complex marine plastic cycle, with negative implications for human and ecosystem health. Yet, observations are currently limited. In this Perspective, we quantify the processes and fluxes of the marine-atmospheric micro(nano)plastic cycle, with the aim of highlighting the remaining unknowns in atmospheric micro(nano)plastic transport. Between 0.013 and 25 million metric tons per year of micro(nano)plastics are potentially being transported within the marine atmosphere and deposited in the oceans. However, the high uncertainty in these marine-atmospheric fluxes is related to data limitations and a lack of study intercomparability. To address the uncertainties and remaining knowledge gaps in the marine-atmospheric micro(nano)plastic cycle, we propose a future global marine-atmospheric micro(nano)plastic observation strategy, incorporating novel sampling methods and the creation of a comparable, harmonized and global data set. Together with long-term observations and intensive investigations, this strategy will help to define the trends in marine-atmospheric pollution and any responses to future policy and management actions. Atmospheric transport of microplastics could be a major source of plastic pollution to the ocean, yet observations currently remain limited. This Perspective quantifies the known budgets of the marine-atmospheric micro(nano)plastic cycle and proposes a future global observation strategy.Peer reviewe

Eyes wide open: perceived exploitation and its consequences

Drawing on the array of literature on exploitation from several social science disciplines, we propose a new way of seeing employer-employee relationships by introducing the concept of perceived exploitative employee-organization relationships, distinguish it from related concepts, and conduct five studies to develop a scale and test our theoretical model of the effects of such employee perceptions. Contributing to the Employee-Organization Relationships and workplace emotions literatures, perceived exploitation is defined as employees’ perceptions that they have been purposefully taken advantage of in their relationship with the organization, to the benefit of the organization itself. We propose and find that such perceptions are associated with both outward-focused emotions of anger and hostility toward the organization and inward-focused ones of shame and guilt at remaining in an exploitative job. In two studies including construction workers and a time-lagged study of medical residents, we find that the emotions of anger and hostility partially mediate the effects of perceived exploitation on employee engagement, revenge against the organization, organizational commitment, and turnover intentions, whereas the emotions of shame and guilt partially mediate the effects of perceived exploitation on employee burnout, silence, and psychological withdrawal

Effects of conversion of native cerrado vegetation to pasture on soil hydro-physical properties, evapotranspiration and streamflow on the Amazonian agricultural frontier

Understanding the impacts of land-use change on landscape-hydrological dynamics is one of the main challenges in the Northern Brazilian Cerrado biome, where the Amazon agricultural frontier is located. Motivated by the gap in literature assessing these impacts, we characterized the soil hydro-physical properties and quantified surface water fluxes from catchments under contrasting land-use in this region. We used data from field measurements in two headwater micro-catchments with similar physical characteristics and different land use, i.e. cerrado sensu stricto vegetation and pasture for extensive cattle ranching. We determined hydraulic and physical properties of the soils, applied ground-based remote sensing techniques to estimate evapotranspiration, and monitored streamflow from October 2012 to September 2014. Our results show significant differences in soil hydro-physical properties between the catchments, with greater bulk density and smaller total porosity in the pasture catchment. We found that evapotranspiration is smaller in the pasture (639 ± 31% mm yr-1) than in the cerrado catchment (1,004 ± 24% mm yr-1), and that streamflow from the pasture catchment is greater with runoff coefficients of 0.40 for the pasture and 0.27 for the cerrado catchment. Overall, our results confirm that conversion of cerrado vegetation to pasture causes soil hydro-physical properties deterioration, reduction in evapotranspiration reduction, and increased streamflow

Distinct β-arrestin- and G protein-dependent pathways for parathyroid hormone receptor-stimulated ERK1/2 activation

International audienc

Potential impacts of climate change on groundwater supplies to the Doñana wetland, Spain

Climate change impacts on natural recharge and groundwater-wetland dynamics were investigated for the Almonte-Marismas aquifer, Spain, which supports the internationally important Doñana wetland. Simulations were carried out using outputs from 13 global climate models to assess the impacts of climate change. Reductions in flow from the aquifer to streams and springs flooding the wetland, induced by changes in recharge according to different climate projections, were modelled. The results project that the change in climate by the 2080s, under a medium-high greenhouse gas emissions scenario, leads to a reduction in groundwater resources. The reduction in mean recharge ranges from 14%–57%. The simulations show that there is an impact on hydraulic head in terms of the overall water table configuration with decreases in groundwater level ranging from 0–17 m. Most simulations produce lower discharge rates from the aquifer to stream basins, with significant reductions in the larger La Rocina (between −55% and −25%) and Marismas (between −68% and −43%) catchments. Water flows from these two basins are critical to maintain aquatic life in the wetland and riparian ecosystems. Modelled climate-induced reductions in total groundwater discharge to the surface are generally larger than current groundwater abstraction rates. The results highlight that effective strategies for groundwater resources management in response to future climate change are imperative