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The interaction of river and marine processes in the fluvial to marine transition zone fundamentally impacts delta plain morphology and sedimentary dynamics. This study aims to improve existing models of the facies distribution, stratigraphic architecture and preservation in the fluvial to marine transition zone of mixed‐process deltas, using a comprehensive sedimentological and stratigraphic dataset from the Middle Miocene Lambir Formation, Baram Delta Province, north‐west Borneo. Eleven facies associations are identified and interpreted to preserve the interaction of fluvial and marine processes in a mixed‐energy delta, where fluvial, wave and tidal processes display spatially and temporally variable interactions. Stratigraphic successions in axial areas associated with active distributary channels are sandstone‐rich, comprising fluvial‐dominated and wave‐dominated units. Successions in lateral areas, which lack active distributary channels, are mudstone‐rich, comprising fluvial‐dominated, tide‐dominated and wave‐dominated units, including mangrove swamps. Widespread mudstone preservation in axial and lateral areas suggests well‐developed turbidity maximum zones, a consequence of high suspended‐sediment concentrations resulting from tropical weathering of a mudstone‐rich hinterland. Within the fluvial to marine transition zone of distributary channels, interpreted proximal–distal sedimentological and stratigraphic trends suggest: (i) a proximal fluvial‐dominated, tide‐influenced subzone; (ii) a distal fluvial‐dominated to wave‐dominated subzone; and (iii) a conspicuously absent tide‐dominated subzone. Lateral areas preserve a more diverse spectrum of facies and stratigraphic elements reflecting combined storm, tidal and subordinate river processes. During coupled storm and river floods, fluvial processes dominated the fluvial to marine transition zone along major and minor distributary channels and channel mouths, causing significant overprinting of preceding interflood deposits. Despite interpreted fluvial–tidal channel units and mangrove influence implying tidal processes, there is a paucity of unequivocal tidal indicators (for example, cyclical heterolithic layering). This suggests that process preservation in the fluvial to marine transition zone preserved in the Lambir Formation primarily records episodic (flashy) river discharge, river flood and storm overprinting of tidal processes, and possible backwater dynamics. [ABSTRACT FROM AUTHOR]

The 2 to 5 km thick, sandstone‐dominated (>90%) Jura Quartzite is an extreme example of a mature Neoproterozoic sandstone, previously interpreted as a tide‐influenced shelf deposit and herein re‐interpreted within a fluvio‐tidal deltaic depositional model. Three issues are addressed: (i) evidence for the re‐interpretation from tidal shelf to tidal delta; (ii) reasons for vertical facies uniformity; and (iii) sand supply mechanisms to form thick tidal‐shelf sandstones. The predominant facies (compound cross‐bedded, coarse‐grained sandstones) represents the lower parts of metres to tens of metres high, transverse fluvio‐tidal bedforms with superimposed smaller bedforms. Ubiquitous erosional surfaces, some with granule–pebble lags, record erosion of the upper parts of those bedforms. There was selective preservation of the higher energy, topographically‐lower, parts of channel‐bar systems. Strongly asymmetrical, bimodal, palaeocurrents are interpreted as due to associated selective preservation of fluvially‐enhanced ebb tidal currents. Finer‐grained facies are scarce, due largely to suspended sediment bypass. They record deposition in lower‐energy environments, including channel mouth bars, between and down depositional‐dip of higher energy fluvio‐ebb tidal bars. The lack of wave‐formed sedimentary structures and low continuity of mudstone and sandstone interbeds, support deposition in a non‐shelf setting. Hence, a sand‐rich, fluvial–tidal, current‐dominated, largely sub‐tidal, delta setting is proposed. This new interpretation avoids the problem of transporting large amounts of coarse sand to a shelf. Facies uniformity and vertical stacking are likely due to sediment oversupply and bypass rather than balanced sediment supply and subsidence rates. However, facies evidence of relative sea level changes is difficult to recognise, which is attributed to: (i) the areally extensive and polygenetic nature of the preserved facies, and (ii) a large stored sediment buffer that dampened response to relative sea‐level and/or sediment supply changes. Consideration of preservation bias towards high‐energy deposits may be more generally relevant, especially to thick Neoproterozoic and Lower Palaeozoic marine sandstones. [ABSTRACT FROM AUTHOR]

This paper studies the expressive and computational power of discrete Ordinary Differential Equations (ODEs), a.k.a. (Ordinary) Difference Equations. It presents a new framework using these equations as a central tool for computation and algorithm design. We present the general theory of discrete ODEs for computation theory, we illustrate this with various examples of algorithms, and we provide several implicit characterizations of complexity and computability classes. The proposed framework presents an original point of view on complexity and computation classes. It unifies several constructions that have been proposed for characterizing these classes including classical approaches in implicit complexity using restricted recursion schemes, as well as recent characterizations of computability and complexity by classes of continuous ordinary differential equations. It also helps understanding the relationships between analog computations and classical discrete models of computation theory. At a more technical point of view, this paper points out the fundamental role of linear (discrete) ODEs and classical ODE tools such as changes of variables to capture computability and complexity measures, or as a tool for programming many algorithms. [ABSTRACT FROM AUTHOR]

Scientific determinations are often at the heart of environmental disputes. When those disputes take the form of litigation, the courts may be called on to determine whether an administrative agency's treatment of the science warrants deference. For several reasons, judges are inclined to apply deferential review to agency factual and science-based policy determinations. Most judges are not trained in the language and methods of science. They may be reluctant to intervene on matters on which their lack of expertise risks producing uninformed judgments. If a statute delegates to an agency the responsibility of making those determinations, courts may be loath to usurp that authority by substituting their judgment for the agency's. If the statutory delegations authorize agencies to premise their decisions on the best available information, courts may regard that authorization as a signal not to take agencies to task for failing to do the impossible. Those mandates reflect a congressional judgment that agency determinations should pass judicial muster even if they fall short of conclusiveness, which may be impossible to achieve. Finally, when technical issues arise in the context of uncertainty at "the frontiers of scientific knowledge," the Supreme Court has warned judges that highly deferential review is required. This Article describes a study analyzing cases decided by the federal courts over a period of thirty years that presented issues involving scientific uncertainty tied to climate change that arose under two key environmental statutes, the National Environmental Policy Act and the Endangered Species Act. The Article provides both quantitative and qualitative analyses of those cases, focusing on ascertaining the factors that drove courts to apply either deferential or non-deferential review. We found, as might be expected, that the courts applied deferential review in the majority of climate change cases arising under these two laws that presented disputes in which litigants challenged agency resolution of factual or policy matters characterized by scientific uncertainty. In the remaining cases, however, the courts, applying the arbitrary and capricious standard of judicial review, refused to defer, engaging instead in relatively rigorous review of agency science. They did so for any one of several reasons, including irrationality in agency reasoning, incomplete analysis of record science, evidentiary shortcomings, and end result-oriented reasoning. These practices induced courts to reject rote acceptance of agency pleas for deference to their scientific expertise. The Article concludes by suggesting further studies that may be useful in understanding how courts can be expected to strike the balance between deferential review and insistence that agencies provide adequate reasons for their actions in contexts of scientific uncertainty. [ABSTRACT FROM AUTHOR]

The rise of food security up international political, societal and academic agendas has led to increasing interest in novel means of improving primary food production and reducing waste. There are however, also many 'post-farm gate' activities that are critical to food security, including processing, packaging, distributing, retailing, cooking and consuming. These activities all affect a range of important food security elements, notably availability, affordability and other aspects of access, nutrition and safety. Addressing the challenge of universal food security, in the context of a number of other policy goals (e.g. social, economic and environmental sustainability), is of keen interest to a range of UK stakeholders but requires an up-to-date evidence base and continuous innovation. An exercise was therefore conducted, under the auspices of the UK Global Food Security Programme, to identify priority research questions with a focus on the UK food system (though the outcomes may be broadly applicable to other developed nations). Emphasis was placed on incorporating a wide range of perspectives ('world views') from different stakeholder groups: policy, private sector, non-governmental organisations, advocacy groups and academia. A total of 456 individuals submitted 820 questions from which 100 were selected by a process of online voting and a three-stage workshop voting exercise. These 100 final questions were sorted into 10 themes and the 'top' question for each theme identified by a further voting exercise. This step also allowed four different stakeholder groups to select the top 7-8 questions from their perspectives. Results of these voting exercises are presented. It is clear from the wide range of questions prioritised in this exercise that the different stakeholder groups identified specific research needs on a range of post-farm gate activities and food security outcomes. Evidence needs related to food affordability, nutrition and food safety (all key elements of food security) featured highly in the exercise. While there were some questions relating to climate impacts on production, other important topics for food security (e.g. trade, transport, preference and cultural needs) were not viewed as strongly by the participants. [ABSTRACT FROM AUTHOR]

This paper compares the comovement of individual stock returns across emerging markets. Campbell et al. and Morck et al. have shown that the United States saw rising firm-specific stock return variations, and thus declining comovement, over the second half of the twentieth century. We detect a similar, albeit weaker, pattern in most, but not all, emerging markets. We further find that higher firm-specific variation is associated with greater capital market openness, but not goods market openness. Moreover, this relationship is magnified by institutional integrity (good government). Goods market openness is associated with higher marketwide variation. [ABSTRACT FROM AUTHOR]

The article presents a list of the reviewers of the periodical including the C. Brown, Jay Carlisle and the David Irons.