Thousands of studies have examined party competition in the American states, finding significant consequences for voter turnout, policy adoptions, and more. Long-term patterns of party control have received less attention. Here, we reexamine the operationalization of party competition. We then update Klarner’s state partisan balance data to include state house and senate composition and gubernatorial vote share since the 1930s, adding—in light of the nationalization of American politics—presidential vote share and the proportion of Democrats in each state’s congressional delegation. After establishing a threshold for one-party dominance, we examine the frequency and duration of subnational party monopolies, highlighting regional variations in the relationship between the state and national measures and applying the index to voter turnout. Our analysis reveals that extended periods of one-party dominance – currently on the uptick – are the rule, not the exception, in the American states and are a phenomenon ripe for further exploration.

Meeting the complex demands of conservation requires a multi-skilled workforce operating in a sector that is respected and supported. Although professionalization of conservation is widely seen as desirable, there is no consistent understanding of what that entails. Here, we review whether and how eight elements of professionalization observed in other sectors are applicable to conservation: (1) a defined and respected occupation; (2) official recognition; (3) knowledge, learning, competences and standards; (4) paid employment; (5) codes of conduct and ethics; (6) individual commitment; (7) organizational capacity; and (8) professional associations. Despite significant achievements in many of these areas, overall progress is patchy, and conventional concepts of professionalization are not always a good fit for conservation. Reasons for this include the multidisciplinary nature of conservation work, the disproportionate influence of elite groups on the development and direction of the profession, and under-representation of field practitioners and of Indigenous peoples and local communities with professional-equivalent skills. We propose a more inclusive approach to professionalization that reflects the full range of practitioners in the sector and the need for increased recognition in countries and regions of high biodiversity. We offer a new definition that characterizes conservation professionals as practitioners who act as essential links between conservation action and conservation knowledge and policy, and provide seven recommendations for building a more effective, inclusive and representative profession.

Bottom-heated convection in rotating spherical shells provides a simple analogue for many astrophysical and geophysical fluid systems. We construct a database of 74 three-dimensional numerical convection models to investigate the scaling behaviour of seven diagnostics over a range of Ekman $(10^{-6}\leqslant E\leqslant 10^{-3})$ and Rayleigh $(15\leqslant \widetilde{Ra}\leqslant 18\,000)$ numbers while using a Prandtl number of unity. Our configuration is chosen to model Earth’s core as defined by the fixed flux thermal boundary conditions, radius ratio $r_{i}/r_{o}$ of $0.35$ and a gravity profile that varies linearly with radius. The quantities of interest are the viscous and thermal boundary layer thickness, mean temperature gradient, mean interior temperature, Nusselt number, horizontal flow length scale, and Reynolds number. We find four parameter regimes characterised by different scaling behaviour. For $E\leqslant 10^{-4}$ and low $Ra$ the weakly nonlinear regime is characterised by a balance between viscous, Archimedean and Coriolis forces and the heat transfer is described by weakly nonlinear theory. At low $E$ and moderate $Ra$, the rapidly rotating regime sees inertia take over from viscosity in the global force balance. In this regime the heat transfer scaling has increasing exponent with decreasing Ekman number and shows no saturation to the diffusion free $Ra^{3/2}E^{2}$ scaling. At high $Ra$ and all $E$ the importance of the Coriolis force gradually decreases and all diagnostics continually change in the transitional regime before approaching the scaling behaviour of non-rotating convection.

Global climate change poses significant threats to the Caribbean islands. Yet, little is known about the long-term disturbance regimes in island ecosystems. This research investigates 2000 yr of natural and anthropogenic fire disturbance through the analysis of a latitudinal transect of sediment records from coastal salt ponds in the British Virgin Islands (BVI). The two research objectives in this study are (1) to determine the fire regime history for the BVI over the last 2000 yr and (2) to explore ecological impacts from anthropogenic landscape modification pre- and post-European settlement. The magnitude of anthropogenic landscape modification, including the introduction of agriculture, was investigated through a multiproxy approach using sedimentary records of fossil pollen and charcoal. Our results suggest fire regimes from Belmont Pond, Thatch Island, and Skeleton Pond have been influenced by human activity, particularly during the postsettlement era, from 500 cal yr BP to modern. Our results suggest that fire regimes during the Medieval Climate Anomaly were responding to changes in climate via dominant atmospheric drivers. The presettlement fire regimes from these islands suggest that fires occurred every 90 to 120 yr. This research represents a significant data contribution to a region with little disturbance and vegetation data available.

Five vermiculite samples collected from Béni Bousera, Morocco and four from Palabora, South Africa were investigated by X-ray diffraction, chemical analysis, 57Fe Mössbauer spectroscopy, and 27Al magic angle spinning nuclear magnetic resonance. The X-ray diffraction studies indicate that all vermiculites have very similar crystallographic parameters. The chemical analyses and the NMR spectra indicate that the Béni Bousera vermiculites contain Al3+ cations in both octahedral and tetrahedral sheets and the Palabora vermiculites contain Al3+ in the tetrahedral sheet. The Mössbauer spectra indicate that the Béni Bousera vermiculites contain more Fe2+ cations than the Palabora vermiculites and do not contain tetrahedral Fe3+ cations. The different cation compositions and distribution in the two sets of vermiculites may result from different parent minerals, i.e. chlorite in the case of Béni Bousera and phlogopite in the case of Palabora, and different genetic processes, i.e. weathering in Béni Bousera and hydrothermal alteration in Palabora.

Two phlogopite, two mixed-layer phlogopite-vermiculite, and two vermiculite samples collected from the Palabora Complex of South Africa have been investigated at 295 K by X-ray diffraction, chemical analysis, and Mössbauer spectroscopy. In addition the temperature dependence of the Mössbauer spectra has been measured between 95 and 295 K for one phlogopite and one mixed-layer sample. The results of the chemical analyses and the Mössbauer spectra improve our knowledge of the vermiculitization process in the Palabora Complex. Both techniques indicate oxidation of the Fe ions during the sequence: phlogopite → mixed-layer → vermiculite. Further, the Mössbauer spectra indicate that Fe oxidation occurs mainly in the octahedral sites and suggest that migration and oxidation of the Fe2+ ions from the octahedral sites to the tetrahedral sites may occur during the transformation of phlogopite into a mixed-layer phase. Finally, the vermiculitization process involves both Fe oxidation and loss of K with a concomitant increase in the Mg content.

We consider pressure-driven flow of an ion-carrying viscous Newtonian fluid through a non-uniformly shaped channel coated with a charged deformable porous layer, as a model for blood flow through microvessels that are lined with an endothelial glycocalyx layer (EGL). The EGL is negatively charged and electrically interacts with ions dissolved in the blood plasma. The focus here is on the interplay between electrochemical effects, and the pressure-driven flow through the microvessel. To analyse these effects we use triphasic mixture theory (TMT) which describes the coupled dynamics of the fluid phase, the elastic EGL, ion transport within the fluid and electric fields within the microvessel. The resulting equations are solved numerically using a coupled boundary–finite element method (BEM-FEM) scheme. However, in the physiological regime considered here, ion concentrations and electric potentials vary rapidly over a thin transitional region (Debye layer) that straddles the lumen–EGL interface, which is difficult to resolve numerically. Accordingly we analyse this region asymptotically, to determine effective jump conditions across the interface for BEM-FEM computations within the bulk EGL/lumen. Our results demonstrate that ion–EGL electrical interactions can influence the near-wall flow, causing it to become reversed. This alters the stresses exerted upon the vessel wall, which has implications for the hypothesised role of the EGL as a transmitter of mechanical signals from the blood flow to the endothelial vessel surface.

Using a combination of satellite sensors, field measurements and satellite-uplinked in situ observing stations, we examine the evolution of several large icebergs drifting east of the Antarctic Peninsula towards South Georgia Island. Three styles of calving are observed during drift: ‘rift calvings’, ‘edge wasting’ and ‘rapid disintegration’. Rift calvings exploit large pre-existing fractures generated in the shelf environment and can occur at any stage of drift. Edge wasting is calving of the iceberg perimeter by numerous small edge-parallel, sliver-shaped icebergs, preserving the general shape of the main iceberg as it shrinks. This process is observed only in areas north of the sea-ice edge. Rapid disintegration, where numerous small calvings occur in rapid succession, is consistently associated with indications of surface melt saturation (surface lakes, firn-pit ponding). Freeboard measurements by ICESat indicate substantial increases in ice-thinning rates north of the sea-ice edge (from <10 m a−1 to >30 m a−1), but surface densification is shown to be an important correction (>2 m freeboard loss before the firn saturates). Edge wasting of icebergs in ‘warm’ surface water (sea-ice-free, >−1.8°C) implies a mechanism based on waterline erosion. Rapid disintegration (‘Larsen B-style’ break-up) is likely due to the effects of surface or saturated-firn water acting on pre-existing crevasses, or on wave- or tidally induced fractures. Changes in microwave backscatter of iceberg firn as icebergs drift into warmer climate and experience increased surface melt suggest a means of predicting when floating ice plates are evolving towards disintegration.

We conducted a longitudinal assessment in 466 underweight and 446 normal-weight children aged 6–24 months living in the urban slum of Dhaka, Bangladesh to determine the association between vitamin D and other micronutrient status with upper respiratory tract infection (URI) and acute lower respiratory infection (ALRI). Incidence rate ratios of URI and ALRI were estimated using multivariable generalized estimating equations. Our results indicate that underweight children with insufficient and deficient vitamin D status were associated with 20% and 23–25% reduced risk of URI, respectively, compared to children with sufficient status. Underweight children, those with serum retinol deficiency were at 1·8 [95% confidence interval (CI) 1·4–2·4] times higher risk of ALRI than those with retinol sufficiency. In normal-weight children there were no significant differences between different vitamin D status and the incidence of URI and ALRI. However, normal-weight children with zinc insufficiency and those that were serum retinol deficient had 1·2 (95% CI 1·0–1·5) times higher risk of URI and 1·9 (95% CI 1·4–2·6) times higher risk of ALRI, respectively. Thus, our results should encourage efforts to increase the intake of retinol-enriched food or supplementation in this population. However, the mechanisms through which vitamin D exerts beneficial effects on the incidence of childhood respiratory tract infection still needs further research.

The endothelial glycocalyx layer (EGL) is a macromolecular layer that lines the inner surface of blood vessels. It is believed to serve a number of physiological functions in the microvasculature, including protection of the vessel walls from potentially harmful levels of fluid shear, as a molecular sieve that acts to regulate transendothelial mass transport, and as a transducer of mechanical stress from the vessel lumen. To best fulfil some of its roles, it has been suggested that the EGL redistributes, so that it is thickest at the cell–cell junctions. It has also been suggested that the majority of mechanotransduction occurs through the solid phase of the EGL, rather than via its fluid phase. The difficulties associated with measuring the distribution of the EGL in vivo make these hypotheses difficult to confirm experimentally. Consequently, to gauge the impact of EGL redistribution from a theoretical standpoint, we compute the flow through a porous-lined microvessel, the endothelial surface of which has been informed by confocal microscopy images of a postcapillary venule. Following earlier studies, we model the poroelastohydrodynamics of the EGL using biphasic mixture theory, taking advantage of a recently developed boundary integral representation of these equations to solve the coupled poroelastohydrodynamics using the boundary element method. However, the low permeabilities of the EGL mean that viscous effects are confined to thin layers, thereby also enabling an asymptotic treatment of the dynamics in this limit. In this asymptotic regime, we also consider a two-layer Stokes flow model for the lumen flow to approximate the effect of red blood cells within the lumen. We demonstrate that redistribution of the EGL can have a substantial impact upon microvessel haemodynamics. We also confirm that the bulk of the mechanical stress is indeed carried through the solid phase of the EGL.

Audiometric tests do not adequately reflect the hearing handicap experienced by individuals with hearing loss and account for only part of the variance in hearing handicap perceptions (Weinstein & Ventry, 1983). The present study investigates the relationship between degree of hearing impairment, psychosocial factors and hearing handicap in a New Zealand war veteran sample. Forty-seven veterans (Mean age = 77.51, SD = 5.99) with some degree of hearing impairment completed a questionnaire which included the Hearing Handicap Inventory (HHI) (Newman et al., 1990), the SF36 sub-scales for general health and mental health (Ware, Kosinski & Keller, 1994), questions relating to hearing aid use and demographic details. Audiometric test information for each veteran was accessed through the national war pensions organisation. Analyses revealed no significant relationship between percentage hearing loss and perceptions of hearing handicap. Those who reported lower satisfaction with their hearing aids, those in poorer physical health and those who had been using hearing aids for a longer time reported higher scores on the HHI. These findings suggest that aspects of the rehabilitation process are important factors in the individual's experience of hearing handicap and that non-auditory factors (such as general health) may be essential considerations in this process.