Draining us dry: scarcity discourses in contention over bottled water extraction

Water scarcity is a highly contested concept. The dominant narratives of water scarcity in policy debates have been criticised for prioritising purely quantitative metrics and eliding questions of inequality and power. While much scholarship on water scarcity examines contexts in the global South where potable water infrastructures do not reach most residents, this article examines conflict over commercial water extraction in a Northern setting where access to potable tap water is nearly universal, yet local water supplies are increasingly constrained. It addresses three main questions: (1) How are narratives or discourses of water scarcity mobilised by a range of actors in local conflicts over groundwater extraction for water bottling?; (2) To what extent do these discourses invoke biophysical versus socially produced scarcity, current versus future scarcity, and local versus regional or global scales of scarcity?; and (3) What are the implications of the findings for efforts by environmental advocates and communities to protect local water supplies? We explore these questions by analysing a local case study of conflict over groundwater extraction by the leading bottled water firm, Nestlé Waters, in southwestern Ontario, Canada. We find that the scarcity narratives deployed by local residents, activists, public officials, and bottling industry representatives illustrate the use of several forms of figurative conflation involving geographic and temporal scales of water scarcity, and economic and volumetric forms of scarcity. We argue that this conflation illuminates deeper issues of economic and social justice at the heart of the conflict, which transcend reductionist hydrological assessments of scarcity or abundance.     

Application of decision tools to ethical analysis in biodiversity conservation

Achieving ethically responsible decisions is crucial for the success of biodiversity conservation projects. We adapted the ethical matrix, decision tree, and Bateson's cube to assist in the ethical analysis of complex conservation scenarios by structuring these tools so that they can implement the different value dimensions (environmental, social, and animal welfare) involved in conservation ethics. We then applied them to a case study relative to the decision-making process regarding whether or not to continue collecting biomaterial on the oldest of the two remaining northern white rhinoceroses (Ceratotherium simum cottoni), a functionally extinct subspecies of the white rhinoceros. We used the ethical matrix to gather ethical pros and cons and as a starting point for a participatory approach to ethical decision-making. We used decision trees to compare the different options at stake on the basis of a set of ethical desiderata. We used Bateson's cube to establish a threshold of ethical acceptability and model the results of a simple survey. The application of these tools proved to be pivotal in structuring the decision-making process and in helping reach a shared, reasoned, and transparent decision on the best option from an ethical point of view among those available.     

A framework for definition of logical scenarios for safety assurance of automated driving

Abstract

Objective: In order to introduce automated vehicles on public roads, it is necessary to ensure that these vehicles are safe to operate in traffic. One challenge is to prove that all physically possible variations of situations can be handled safely within the operational design domain of the vehicle. A promising approach to handling the set of possible situations is to identify a manageable number of logical scenarios, which provide an abstraction for object properties and behavior within the situations. These can then be transferred into concrete scenarios defining all parameters necessary to reproduce the situation in different test environments.

Methods: This article proposes a framework for defining safety-relevant scenarios based on the potential collision between the subject vehicle and a challenging object, which forces the subject vehicle to depart from its planned course of action to avoid a collision. This allows defining only safety-relevant scenarios, which can directly be related to accident classification. The first criterion for defining a scenario is the area of the subject vehicle with which the object would collide. As a second criterion, 8 different positions around the subject vehicle are considered. To account for other relevant objects in the scenario, factors that influence the challenge for the subject vehicle can be added to the scenario. These are grouped as action constraints, dynamic occlusions, and causal chains.

Results: By applying the proposed systematics, a catalog of base scenarios for a vehicle traveling on controlled-access highways has been generated, which can directly be linked to parameters in accident classification. The catalog serves as a basis for scenario classification within the PEGASUS project.

Conclusions: Defining a limited number of safety-relevant scenarios helps to realize a systematic safety assurance process for automated vehicles. Scenarios are defined based on the point of the potential collision of a challenging object with the subject vehicle and its initial position. This approach allows defining scenarios for different environments and different driving states of the subject vehicle using the same mechanisms. A next step is the generation of logical scenarios for other driving states of the subject vehicle and for other traffic environments.     

The scent of sun worship: basking experience alters scent mark composition in male lizards

Signals used in female choice should honestly advertise the benefits that males can provide, with direct benefits often argued as being more important than indirect benefits. However, the nature of direct benefits in species without paternal care or nuptial gifts is poorly understood. Previous studies on lizards suggest that females decide where to settle and assumedly who to mate with based on information contained in scent marks from territorial males. Access to high-quality thermal resources is crucial for female reproductive success. Females may therefore be able to detect and exploit thermal-induced variation in the chemical composition of male scent marks when assessing the quality of his territory. We show that the amount of time male wall lizards (Podarcis muralis) are allowed to bask significantly alters the chemical composition of their femoral secretions used in scent marking. The direction of the change is consistent with adaptive plasticity to maintain signalling efficacy under warm conditions that increase evaporation of femoral secretions. The compounds affected by basking experience included those previously associated with male quality or shown to mediate male–male competition in lizards. However, whilst female lizards could discriminate between scent marks of males that had experienced different basking conditions, they did not preferentially associate with the scent from males from high-quality thermal conditions. These results highlight the potential importance of a previously neglected environmental effect on chemical signalling. We suggest thermal effects may have significant consequences for scent-mark composition in variable environments, with potential repercussions on olfactory communication in lizards.     

Raw single-walled carbon nanotube-induced cytotoxic effects in human bronchial epithelial cells: comparison to asbestos

Single-walled carbon nanotubes (SWCNT) are being developed to be used in many industrial and biomedical applications. However, SWCNT's durability and likely fibrous morphology have raised health concerns. The present investigations were focused on understanding the cellular and molecular mechanisms induced by raw SWCNT (SWCNT) in human bronchial-epithelial cells (BEAS-2B). Asbestos (crocidolite) was used as a positive control. Exposure of BEAS-2B cells to SWCNT induced apoptosis, DNA damage, and oxidative stress. The generation of hydroxyl radical (^?OH) and increase of superoxide dismutase (SOD) activity were concentration-dependent. The increase in apoptosis was associated with activation of caspase-3, caspase-7, and poly (ADP-ribose) polymerase-1 (PARP-1). A short recovery period of 6?h of cells from SWCNT exposure resulted in reversal of caspase-3 and caspase-7, and a partial reversal of PARP-1 activation. The activation of PARP-1, caspase-3, and caspase-7 was only partially diminished after a recovery of 6?h from the exposure to crocidolite. Exposure of BEAS-2B cells to SWCNT resulted in the phosphorylation of protein p42/44 (p42/44) and protein p38 (p38). SWCNT did not induce protein serine-threonine kinase (AKT) phosphorylation. For all the above end points, crocidolite induced a greater response compared to SWCNT. SWCNT induced a significant activation of activator protein-1 (AP-1) and nuclear factor kappa B (NF-κB), and the effect was inhibited by mitogen-activated protein kinase (MAPK) inhibitors. SWCNT also induced significant increase in the expression levels of c-Jun, βIGH3, and CD44 genes. The results of this study show that the molecular mechanism for raw SWCNT-mediated toxicity in BEAS-2B cells is through the activation of caspase-3, caspase-7, and PARP-1. Furthermore, the mechanism of AP-1 and NF-κB activation is through MAPK. This bioactivity of raw SWCNT is associated with the generation of oxidative stress and DNA damage. Considering the role of airway epithelium as a critical barrier for normal pulmonary function and focal point for tumor development, this study demonstrates that raw SWCNT activate molecular events which may be linked to adverse biological responses implicated in pulmonary diseases.     

Assessment of the Nested Grid Model Estimates for Driving Regional Visibility Models in the Southwestern United States

ABSTRACT

The Nested Grid Model (NGM) is a primitive-equation meteorological model that is routinely exercised over North America for forecasting purposes by the National Meteorological Center. While prognostic meteorological models are being increasingly used to drive air quality models, their use in conducting annual simulations requires significant resources. NGM estimates of wind fields and other meteorological variables provide an attractive alternative since they are typically archived and readily available for an entire year. Preliminary evaluation of NGM winds during the summer of 1992 for application to the region surrounding the Grand Canyon National Park showed serious shortcomings. The NGM winds along the borders between California, Arizona and Mexico tend to be northwesterly with a speed of about 6 m/sec, while the observed flow is predominantly southerly at about 2-5 m/sec. The mesoscale effect of a thermal low pressure area over the highly heated Southern California and western Arizona deserts does not appear to be represented by the NGM because of its coarse resolution and the use of sparse observations in that region. Tracer simulations and statistical evaluation against special high resolution observations of winds in the southwest United States clearly demonstrate the northwest bias in NGM winds and its adverse effect on predictions of an air quality model. The “enhanced” NGM winds, in which selected wind observations are incorporated in the NGM winds using a diagnostic meteorological model provide additional confirmation on the primary cause of the northwest bias. This study has demonstrated that in situations where limited resources prevent the use of prognostic meteorological models, previously archived coarse resolution wind fields in which additional observations are incorporated to correct known biases provide an attractive option.     

Applying artificial neural network methodology to ocean color remote sensing

Artificial neural networks (ANN) are widely used as continuous models to fit non-linear transfer functions. In this study we used ANN to retrieve chlorophyll pigments in the near-surface of oceans from Ocean Color measurements. This bio-optical inversion is established by analyzing concomitant sun-light spectral reflectances over the ocean surface and pigment concentration. The relationships are complex, non-linear, and their biological nature implies a significant variability. Moreover, the sun-light reflectances are usually measured by satellite radiometers flying at 800 km over the ocean surface, which affect the data by adding radiometric noise and atmospheric correction errors. By comparison with the polynomial fit usually employed to treat this problem, we show the advantages of neural function approximation like the association of non-linear complexity and noise filtering.     

ESTIMATION OF LONG-TERM DISCHARGE STATISTICS BY REGIONAL ADJUSTMENT1

ABSTRACT: A regional adjustment relationship was developed to estimate long-term (30-year) monthly median discharges from short term (three-year) records. This method differs from traditional approaches in that it is based on site-specific discharge data but does not require correlation of these data with discharges from a single hydrologically similar long-term gage. The method is shown to be statistically robust, and applicable to statistics other than the median.     

Tagging Diesel and Residential Oil Furnace Emissions in Roanoke,Virginia, with Enriched Isotopes of Samarium

Stable isotopic tracers were used in Roanoke, Virginia, to tag particulate emissions from diesel trucks and residential oil furnaces, two sources of soot and PAHs which cannot be differentiated on the basis of known constituents. Approximately 1.6 g of enriched ¹⁴⁹Sm were used to tag 264 m³ of diesel fuel burned by the city bus and truck fleets; 0.39 g of ¹⁵⁰Sm were used to tag 106 m³ of residential heating oil. Picogram amounts of the tracers were determined simultaneously by thermal-ionization mass spectrometry in fine particles collected within the city at signal-to-noise ratios as large as 6000. These results demonstrate the feasibility of tracing particles from multiple combustion sources with stable, separated isotopes.