Modernism, postmodernism, and corporate power : historicizing the architectural typology of the corporate campus

This paper explores the potential for a ‘marriage’ of history and critical organization studies through a conceptual synthesis of critical sociology and historiography and its application to a specific organizational phenomenon. It presents a case study of the architecture of the corporate campus headquarters, a type of business complex built in exurban, rural settings, focusing on a series of campuses built in the period 1945–2005. The main purpose of this research is to identify what the transition from architectural Modernism to Postmodernism tells us about the evolution of ideologies that animate corporations in relation to wider developments in capitalism. Our conceptual framework has temporal and spatial dimensions, drawing on architectural historiography and sociological concepts, thus allowing us to connect architecture and the social in relation to the production and projection of corporate power through a delimited historical period. We identify two main drivers behind the construction of the campuses: internally, to integrate the staff as a community, and externally, to project a desired corporate image. We also demonstrate how our conceptual synthesis sheds light on the rise and fall of individual corporations. We make the following contributions to management and organizational history: first, we demonstrate how studying organizations through the lens of corporate architecture helps us understand the connections between symbolic, social and physical space and forms of corporate power. Second, we show how a marriage of history and critical sociology can help us to understand how certain ideologically freighted architectural features endure – or return – within the changing configurations of capitalism and finally, methodologically, we demonstrate how historicizing architecture can shed light on the rise and fall of individual corporations within a given socio-historical context

Lag effects in the impacts of mass coral bleaching on coral reef fish, fisheries, and ecosystems

Recent episodes of coral bleaching have led to wide-scale loss of reef corals and raised concerns over the effectiveness of existing conservation and management efforts. The 1998 bleaching event was most severe in the western Indian Ocean, where coral declined by up to 90% in some locations. Using fisheries-independent data, we assessed the long-term impacts of this event on fishery target species in the Seychelles, the overall size structure of the fish assemblage, and the effectiveness of two marine protected areas (MPAs) in protecting fish communities. The biomass of fished species above the size retained in fish traps changed little between 1994 and 2005, indicating no current effect on fishery yields. Biomass remained higher in MPAs, indicating they were effective in protecting fish stocks. Nevertheless, the size structure of the fish communities, as described with size-spectra analysis, changed in both fished areas and MPAs, with a decline in smaller fish (<30 cm) and an increase in larger fish (>45 cm). We believe this represents a time-lag response to a reduction in reef structural complexity brought about because fishes are being lost through natural mortality and fishing, and are not being replaced by juveniles. This effect is expected to be greater in terms of fisheries productivity and, because congruent patterns are observed for herbivores, suggests that MPAs do not offer coral reefs long-term resilience to bleaching events. Corallivores and planktivores declined strikingly in abundance, particularly in MPAs, and this decline was associated with a similar pattern of decline in their preferred corals. We suggest that climate-mediated disturbances, such as coral bleaching, be at the fore of conservation planning for coral reefs.\u

Boom and bust of keystone structure on coral reefs

Repeated bouts of coral bleaching threaten the long-term persistence of coral reefs and associated communities. Here, we document the short- and long-term impacts of heatwave events on coral and fish assemblages, based on regular surveys of 18 reefs of the granitic islands of Seychelles over 23 yr. Extreme heat events in 1998 and 2016 led to bleaching-associated declines in coral cover, whilst between these years there was an interim period of coral recovery on some reefs. Coral decline and recovery were primarily due to changes in the cover of branching coral, particularly those from the families Acroporidae and Pocilloporidae. Surveys during the 2016 bleaching found that 95% of the 468 Acropora and Pocillopora colonies observed were either bleached or recently dead. The extent of bleaching and subsequent mortality were best explained by a priori assessments of community susceptibility to heat stress. One year later (2017), coral cover had fallen by 70% and average coverage across the 18 reefs was at 6%, similar to levels recorded in 2005, 7 yr after the 1998 bleaching. Decline in coral following the 2016 bleaching coincided with reduced abundance of fish < 11 cm TL, particularly corallivores, invertivores and mixed diet feeders. These changes are likely to foreshadow more widespread loss once the habitat structure erodes. Accordingly, 7 yr after the 1998 bleaching, when coral skeletons and reef structure had collapsed on some reefs, abundance of both large- and small-bodied fish had declined. We show that fluctuation in the cover of branching coral is positively associated with changes in the abundance of small-bodied fish which contribute to ecological processes and high diversity, suggesting branching corals are a keystone structure. Increased frequency of bleaching threatens the capacity of branching corals to fully recover after disturbances, reducing the amplitude of boom bust cycles of these corals and the keystone habitat structure they provide reef fish

Thermal stress induces persistently altered coral reef fish assemblages

Ecological communities are reorganizing in response to warming temperatures. For continuous ocean habitats this reorganization is characterized by large-scale species redistribution, but for tropical discontinuous habitats such as coral reefs, spatial isolation coupled with strong habitat dependence of fish species imply that turnover and local extinctions are more significant mechanisms. In these systems, transient marine heatwaves are causing coral bleaching and profoundly altering habitat structure, yet despite severe bleaching events becoming more frequent and projections indicating annual severe bleaching by the 2050s at most reefs, long-term effects on the diversity and structure of fish assemblages remain unclear. Using a 23-year time series spanning a thermal stress event, we describe and model structural changes and recovery trajectories of fish communities after mass bleaching. Communities changed fundamentally, with the new emergent communities dominated by herbivores and persisting for >15 years, a period exceeding realized and projected intervals between thermal stress events on coral reefs. Reefs which shifted to macroalgal states had the lowest species richness and highest compositional dissimilarity, whereas reefs where live coral recovered exceeded prebleaching fish richness, but remained dissimilar to prebleaching compositions. Given realized and projected frequencies of bleaching events, our results show that fish communities historically associated with coral reefs will not re-establish, requiring substantial adaptation by managers and resource users

Abiotic and biotic controls on coral recovery 16 years after mass bleaching

As climate changes increase heat stress on tropical ecosystems, the long-term persistence of coral reefs requires rapid coral recovery following coral bleaching events. Using the extent of coral cover return to a pre-bleaching baseline as a benchmark, recovery of fast-growing and stress-tolerant coral growth forms suggests that reefs can bounce back between repeated disturbances if given adequate time and protection from anthropogenic disturbances. However, long-term recovery dynamics of coral communities following severe bleaching and mass mortality are limited, particularly for fringing reefs along inhabited coastlines where human stressors may compromise recovery potential. Here, we examine the dynamics and drivers of coral recovery in Seychelles, where 12 reefs returned to pre-bleaching coral cover levels after a severe bleaching event caused > 95% coral mortality. Six reefs with initially low cover (<25%) recovered within 7–12 yr and, after 16 yr, exceeded pre-bleaching cover levels by 132–305%. In contrast, six reefs with initially high cover (20–60%) remained at 48–93% of pre-bleaching levels, with recovery projected to take 17–29 yr. Abiotic and historic conditions constrained recovery rates, with the slowest recovery times observed on deep and wave-exposed reefs with high pre-bleaching coral cover. Reefs with high juvenile coral densities and low nitrogen levels recovered fastest, possibly due to the interplay between nutrient enrichment, algal proliferation, and coral recruitment. Our findings emphasize the importance of understanding small-scale variation in recovery potential, whereby recovery times were governed by natural limits on growth rates and modified by coral recruitment and nutrient enrichment. Ultimately, climate-impacted reefs can recover to moderate coral cover levels, but, if bleaching causes repeated high coral mortality, short recovery windows will prevent a return to historic levels of coral dominance. © 2019, The Author(s)

Probability density function of turbulent velocity fluctuations in rough-wall boundary layer

The probability density function of single-point velocity fluctuations in turbulence is studied systematically using Fourier coefficients in the energy-containing range. In ideal turbulence where energy-containing motions are random and independent, the Fourier coefficients tend to Gaussian and independent of each other. Velocity fluctuations accordingly tend to Gaussian. However, if energy-containing motions are intermittent or contaminated with bounded-amplitude motions such as wavy wakes, the Fourier coefficients tend to non-Gaussian and dependent of each other. Velocity fluctuations accordingly tend to non-Gaussian. These situations are found in our experiment of a rough-wall boundary layer.Comment: 6 pages, to appear in Physical Review

Neutral Plasma Oscillations at Zero Temperature

We use cold plasma theory to calculate the response of an ultracold neutral plasma to an applied rf field. The free oscillation of the system has a continuous spectrum and an associated damped quasimode. We show that this quasimode dominates the driven response. We use this model to simulate plasma oscillations in an expanding ultracold neutral plasma, providing insights into the assumptions used to interpret experimental data [Phys. Rev. Lett. 85, 318 (2000)].Comment: 4.3 pages, including 3 figure

Spin density wave dislocation in chromium probed by coherent x-ray diffraction

We report on the study of a magnetic dislocation in pure chromium. Coherent x-ray diffraction profiles obtained on the incommensurate Spin Density Wave (SDW) reflection are consistent with the presence of a dislocation of the magnetic order, embedded at a few micrometers from the surface of the sample. Beyond the specific case of magnetic dislocations in chromium, this work may open up a new method for the study of magnetic defects embedded in the bulk.Comment: 8 pages, 7 figure

Comparative analysis of pedestrian injuries using police, emergency department, and death certificate data sources in North Carolina, U.S., 2007–2012

Pedestrian safety programs are needed to address the rising incidence of pedestrian fatalities. Unfortunately, most communities lack comprehensive information on the circumstances of pedestrian crashes and resulting injuries that could help guide decision-making for prevention program development and implementation. This study aimed to evaluate how three commonly available data sources (police-reported pedestrian crashes, emergency department [ED] visits, and death certificates) define and capture pedestrian injury data, and to compare the distribution of pedestrian injuries and fatalities across these data sources. Existing state-wide data sources in North Carolina, U.S.A.,—police-reported pedestrian crashes, ED visits, and death certificates—were used to perform a descriptive analysis of temporal and demographic pedestrian injury severity distributions for a 6-year period (2007–2012). After excluding non-relevant cases, there were 12,646 police-reported pedestrian crashes, 17,369 pedestrian-injury-related ED visits, and 993 pedestrian-related death certificate cases. Pedestrian injury distributions appeared similar across the three data sets in relation to pedestrian sex, age, and temporality. Police data (which represented crashes rather than all pedestrians involved in a crash) likely underrepresented pedestrian injury incidence, while ED data (which represented ED visits, with multiple visits per person possible) likely overrepresented pedestrian injury incidence. The study provides a better understanding of the discrepancies between pedestrian injury data sources and key considerations when using police, ED, and death certificate data for surveillance or injury prevention efforts

Vortex interaction in patches of randomly placed emergent cylinders

The flow field of multiple-cylinder configurations exhibits complex interactions between shear layers, vortexes and wakes. For high stem-Reynolds numbers, the flow is turbulent and, low and intermediate areal number-densities of cylinders, and turbulence is produced mostly by the work of Reynolds shear stresses in the horizontal plane (uv component) against the time-averaged shear rate characteristic of vertical-axis vortex shedding in the wake of cylinders. The spatial pattern of turbulent production and of other terms of the equation of conservation of Turbulent Kinetic Energy (TKE) is thus mostly determined by the interaction of vortexes shed by individual cylinders and by the distance between cylinders. The main objective of this paper is to advance on the understanding of vortex interaction in patches of randomly placed emergent and rigid cylinders. In particular, the relation between cylinder Strouhal numbers, vortex decay and vortex path statistics is investigated for isolated cylinder and for a cylinder within an array of randomly placed cylinders with a areal-number density of 980 cylinders/m2. Results are compared to shed light on the influence of neighbouring cylinders. An experimental database acquired with 2D Particle Image Velocimetry (PIV) was explored. A methodology to detect vortexes in 2D flow fields is proposed. It features a point-based criterion and a global search to detect all the possible vortex core locations, combined with a curve-based criterion, to decide whether the detected point corresponds to a vortex, depending on the geometry of streamlines. The results show a decrease on the amount of vortexes and a shorter vortex life for the cylinder within the array when compared with the isolated cylinder. The averaged vortex path is also affected by the presence of neighbouring cylinders. Concerning the Strouhal number, the normalized shedding frequency is approximately the same for both studied cases