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A terrestrial (lacustrine and fluvial) palaeoclimate record from Hoxne (Suffolk, UK) shows two temperate phases separated by a cold episode, correlated with MIS 11 subdivisions corresponding to isotopic events 11.3 (Hoxnian interglacial period), 11.24 (Stratum C cold interval), and 11.23 (warm interval with evidence of human presence). A robust, reproducible multiproxy consensus approach validates and combines quantitative palaeotemperature reconstructions from three invertebrate groups (beetles, chironomids, and ostracods) and plant indicator taxa with qualitative implications of molluscs and small vertebrates. Compared with the present, interglacial mean monthly air temperatures were similar or up to 4.0°C higher in summer, but similar or as much as 3.0°C lower in winter; the Stratum C cold interval, following prolonged nondeposition or erosion of the lake bed, experienced summers 2.5°C cooler and winters between 5°C and 10°C cooler than at present. Possible reworking of fossils into Stratum C from underlying interglacial assemblages is taken into account. Oxygen and carbon isotopes from ostracod shells indicate evaporatively enriched lake water during Stratum C deposition. Comparative evaluation shows that proxy-based palaeoclimate reconstruction methods are best tested against each other and, if validated, can be used to generate more refined and robust results through multiproxy consensus.
Political event data are widely used in studies of political violence. Recent years have seen notable advances in the automated coding of political event data from international news sources. Yet, the validity of machine-coded event data remains disputed, especially in the context of event geolocation. We analyze the frequencies of human- and machine-geocoded event data agreement in relation to an independent (ground truth) source. The events are human rights violations in Colombia. We perform our evaluation for a key, 8-year period of the Colombian conflict and in three 2-year subperiods as well as for a selected set of (non)journalistically remote municipalities. As a complement to this analysis, we estimate spatial probit models based on the three datasets. These models assume Gaussian Markov Random Field error processes; they are constructed using a stochastic partial differential equation and estimated with integrated nested Laplacian approximation. The estimated models tell us whether the three datasets produce comparable predictions, underreport events in relation to the same covariates, and have similar patterns of prediction error. Together the two analyses show that, for this subnational conflict, the machine- and human-geocoded datasets are comparable in terms of external validity but, according to the geostatistical models, produce prediction errors that differ in important respects.
Morbidities and mortalities caused by malaria are still a serious issue in Nigeria, with the country accounting for 25% of malaria morbidities and 24% of malaria mortalities globally in 2018. Treated bed nets reduce the incidence of malaria, but not all Nigerians use them. This study aimed to examine the factors associated with treated bed net usage, including perceived severity of malaria, and the rural–urban differences in the relationship between socio-demographic factors and use of treated bed nets in Nigeria. The analytic sample size comprised 40,693 women aged 15–49 years. Poisson regression and bivariable and multivariable analyses were used to test the study hypothesis that women who agreed that malaria could potentially lead to death would be more likely to adopt malaria preventive measures, including treated bed net use. About 48% of the women slept under a treated mosquito net the night before the survey. Those who perceived that malaria could lead to death had a higher likelihood of using a treated bed net in the urban, rural and combined samples. However, in the multivariable model, the association between perceived malaria severity and use of a treated bed net was only significant for rural women (APR=0.964, 95% CI: 0.933, 0.996). The results unexpectedly suggest that rural Nigerian women who perceive malaria to be severe have a lower likelihood of using treated bed nets. Also, rural–urban variations in the relationship between the socio-demographic variables and use of treated bed nets were observed. Policies should consider the observed rural–urban dichotomy in the influence of perceived severity of malaria and other socio-demographic factors on women’s use of treated bed nets in Nigeria.
Studies that reveal detailed information about trilobite growth, particularly early developmental stages, are crucial for improving our understanding of the phylogenetic relationships within this iconic group of fossil arthropods. Here we document an essentially complete ontogeny of the trilobite Redlichia cf. versabunda from the Cambrian Series 2 (late Stage 4) Ramsay Limestone of Yorke Peninsula in South Australia, including some of the best-preserved protaspides (the earliest biomineralized trilobite larval stage) known for any Cambrian trilobite. These protaspid stages exhibit similar morphological characteristics to many other taxa within the Suborder Redlichiina, especially to closely related species such as Metaredlichia cylindrica from the early Cambrian period of China. Morphological patterns observed across early developmental stages of different groups within the Order Redlichiida are discussed. Although redlichiine protaspides exhibit similar overall morphologies, certain ontogenetic characters within this suborder have potential phylogenetic signal, with different superfamilies characterized by unique trait combinations in these early growth stages.
In order to maximize the utility of future studies of trilobite ontogeny, we propose a set of standard practices that relate to the collection, nomenclature, description, depiction, and interpretation of ontogenetic series inferred from articulated specimens belonging to individual species. In some cases, these suggestions may also apply to ontogenetic studies of other fossilized taxa.
This work investigated the photophysical pathways for light absorption, charge generation, and charge separation in donor–acceptor nanoparticle blends of poly(3-hexylthiophene) and indene-C60-bisadduct. Optical modeling combined with steady-state and time-resolved optoelectronic characterization revealed that the nanoparticle blends experience a photocurrent limited to 60% of a bulk solution mixture. This discrepancy resulted from imperfect free charge generation inside the nanoparticles. High-resolution transmission electron microscopy and chemically resolved X-ray mapping showed that enhanced miscibility of materials did improve the donor–acceptor blending at the center of the nanoparticles; however, a residual shell of almost pure donor still restricted energy generation from these nanoparticles.
The scarcity of Romano-British human remains from north-west England has hindered understanding of burial practice in this region. Here, we report on the excavation of human and non-human animal remains1 and material culture from Dog Hole Cave, Haverbrack. Foetal and neonatal infants had been interred alongside a horse burial and puppies, lambs, calves and piglets in the very latest Iron Age to early Romano-British period, while the mid- to late Roman period is characterised by burials of older individuals with copper-alloy jewellery and beads. This material culture is more characteristic of urban sites, while isotope analysis indicates that the later individuals were largely from the local area. We discuss these results in terms of burial ritual in Cumbria and rural acculturation. Supplementary material is available online (https://doi.org/10.1017/S0068113X20000136), and contains further information about the site and excavations, small finds, zooarchaeology, human osteology, site taphonomy, the palaeoenvironment, isotope methods and analysis, and finds listed in Benson and Bland 1963.
Mutual responsiveness is necessary to sustain a close relationship and, to achieve it, people must protect their overall motivation to act in a caring way against the costs naturally arising from the challenges of maintaining interdependence. These challenges are universal and require solutions that constitute relatively automatic habit structures. The solutions allow people to “keep their eyes on the prize” and sustain their overall rewards without being distracted by the localized costs that occur along the way. For instance, one important challenge involves partners’ behavior that will on occasion interfere with one’s personal goals, by either pursuing their own interests first or failing to coordinate dyadic goals. In a case of motivation cognition, the automatic response to such experiences is to rationalize the negative, costly behavior by exaggerating the partners’ positive features and compensating cognitively for it. However, consistent with the MODE model, if people have the cognitive resources for deliberation, those whose broader goals are more self-protective rather than connective will overturn the pro-relationship impulses, to their ultimate detriment. Research exploring three different automatic procedural rules that illustrate this process of motivated cognition will be described.
Urban areas generate 80 per cent of global GDP (CBD, 1992; Ammann, 2016; Gressel, 2007) and no country has developed without urbanisation, according to Paul Collier (Dobbs et al., 2012; Collier, 2015). Just 2 per cent of the world’s population was urbanised in 1800; the figure passed 50 per cent by 2008, and on current trends it will reach 60 per cent by 2030. Virtually all this urban future growth will take place in developing countries, emulating Western Europe and North America, so that by 2025 it is estimated that 235 million households earning more than US$20,000 pa ppp will live in cities in the emerging economies, compared to 210 million in cities in the developed regions (Department for Business, Innovation and Skills, 2013). Cities are able to harness economies of scale and specialisation through the economies of agglomeration, but they consume 75 per cent of the world’s energy and are responsible for up to 70 per cent of global greenhouse gases (GHGs) (Satterthwaite, 2008).
We propose the concept of the “Fish Revolution” to demarcate the dramatic increase in North Atlantic fisheries after AD 1500, which led to a 15-fold increase of cod (Gadus morhua) catch volumes and likely a tripling of fish protein to the European market. We consider three key questions: (1) What were the environmental parameters of the Fish Revolution? (2) What were the globalising effects of the Fish Revolution? (3) What were the consequences of the Fish Revolution for fishing communities? While these questions would have been considered unknowable a decade or two ago, methodological developments in marine environmental history and historical ecology have moved information about both supply and demand into the realm of the discernible. Although much research remains to be done, we conclude that this was a major event in the history of resource extraction from the sea, mediated by forces of climate change and globalisation, and is likely to provide a fruitful agenda for future multidisciplinary research.
This paper examines retirement saving policy for independent – or contingent – workers, a growing segment of the workforce. Because few of these workers are covered by employer-sponsored retirement plans, they often do not benefit from payroll deduction, employer matching contributions, automatic enrollment, and other provisions that encourage retirement saving. Better use of fintech, judicious changes to tax policy, and expanded Automatic IRAs would help independent workers save for retirement. In addition, we propose the creation of retirement saving accounts that attach to the worker as a supplement to, and possible replacement for, the current system of employer-sponsored accounts.
Background: Despite the global impact of bipolar disorder (BD), treatment success is limited. Challenges include syndromal and subsyndromal mood instability, comorbid anxiety, and uncertainty around mechanisms to target. The Oxford Mood Action Psychology Programme (OxMAPP) offered a novel approach within a cognitive behavioural framework, via mental imagery-focused cognitive therapy (ImCT). Aims: This clinical audit evaluated referral rates, clinical outcomes and patient satisfaction with the OxMAPP service. Method: Eleven outpatients with BD received ImCT in addition to standard psychiatric care. Mood data were collected weekly from 6 months pre-treatment to 6 months post-treatment via routine mood monitoring. Anxiety was measured weekly from start of treatment until 1 month post-treatment. Patient feedback was provided via questionnaire. Results: Referral and treatment uptake rates indicated acceptability to referrers and patients. From pre- to post-treatment, there was (i) a significant reduction in the duration of depressive episode relapses, and (ii) a non-significant trend towards a reduction in the number of episodes, with small to medium effect size. There was a large effect size for the reduction in weekly anxiety symptoms from assessment to 1 month follow-up. Patient feedback indicated high levels of satisfaction with ImCT, and underscored the importance of the mental imagery focus. Conclusions: This clinical audit provides preliminary evidence that ImCT can help improve depressive and anxiety symptoms in BD as part of integrated clinical care, with high patient satisfaction and acceptability. Formal assessment designs are needed to further test the feasibility and efficacy of the new ImCT treatment on anxiety and mood instability.
Textual data are plagued by underreporting bias. For example, news sources often fail to report human rights violations. Cook et al. propose a multi-source estimator to gauge, and to account for, the underreporting of state repression events within human codings of news texts produced by the Agence France-Presse and Associated Press. We evaluate this estimator with Monte Carlo experiments, and then use it to compare the prevalence and seriousness of underreporting when comparable texts are machine coded and recorded in the World-Integrated Crisis Early Warning System dataset. We replicate Cook et al.’s investigation of human-coded state repression events with our machine-coded events, and validate both models against an external measure of human rights protections in Africa. We then use the Cook et al. estimator to gauge the seriousness and prevalence of underreporting in machine and human-coded event data on human rights violations in Colombia. We find in both applications that machine-coded data are as valid as human-coded data.
Growing crops that exhibit a high level of competition with weeds increases opportunities to practice integrated weed management and reduce herbicide inputs. The recent development and market dominance of hybrid canola cultivars provides an opportunity to reassess the relative competitive ability of canola cultivars with small-grain cereals. Direct-seeded (no-till) experiments were conducted at five western Canada locations from 2006 to 2008 to compare the competitive ability of canola cultivars vs. small-grain cereals. The relative competitive ability of the species and cultivars was determined by assessing monocot and dicot weed biomass at different times throughout the growing season as well as oat (simulated weed) seed production. Under most conditions, but especially under warm and relatively dry environments, barley cultivars had the greatest relative competitive ability. Rye and triticale were also highly competitive species under most environmental conditions. Canada Prairie Spring Red wheat and Canada Western Red Spring wheat cultivars usually were the least competitive cereal crops, but there were exceptions in some environments. Canola hybrids were more competitive than open-pollinated canola cultivars. More importantly, under cool, low growing degree day conditions, canola hybrids were as competitive as barley, especially with dicot weeds. Under most conditions, hybrid canola growers on the Canadian Prairies are well advised to avoid the additional selection pressure inherent with a second in-crop herbicide application. Combining competitive cultivars of any species with optimal agronomic practices that facilitate crop health will enhance cropping system sustainability and allow growers to extend the life of their valuable herbicide tools.
There is no published information on the impact of volunteer barley on wheat yield loss or on the economics of controlling barley with a herbicide. With the registration of imazamox-resistant wheat, it is now possible to control volunteer barley in wheat. Thus, the likelihood of growing wheat in rotation with barley may increase. Field experiments were conducted in 2003 and 2004 at Beaverlodge, Lacombe, and Edmonton, AB, Canada, and Saskatoon, SK, Canada, to determine the impact of volunteer barley on yield of imazamox-resistant spring wheat seeded at relatively low (100 kg ha−1) and high (175 kg ha−1) rates. Barley was seeded at different densities to simulate volunteer barley infestations. Regression analysis indicated that wheat-plant density influenced the effects of volunteer barley interference on wheat yield loss, economic threshold values, and volunteer barley fecundity among locations and years. Economic thresholds varied from as few volunteer barley plants as 3 m−2 at Beaverlodge in 2003 and 2004 to 48 m−2 at Lacombe in 2003. In most cases, wheat yield loss and volunteer barley fecundity were lower and economic thresholds were higher when wheat was seeded at the higher rate. For example, averaged over both years at Beaverlodge initial slope values (percentage of wheat yield loss at low barley density) were 4.5 and 1.7%, and economic threshold values of volunteer barley plants were 3 m−2 and 8 m−2 at low and high wheat seeding rates, respectively. Results indicate that volunteer barley can be highly competitive in wheat, but yield losses and wheat seed contamination due to volunteer barley can be alleviated by seeding wheat at a relatively high rate.
The age and number of important fossil-producing late Pleistocene terraces in the Tunica Hills have recently become quite controversial. One hypothesis holds that only a single loess-mantled Farmdalian terrace flanks the streams in this area. The other maintains that there are two terraces. The youngest is considered essentially Holocene in age while the older is Sangamon in age. Radiometric and stratigraphic evidence collected for this study indicates that there are two terraces. The youngest is late Woodfordian to Holocene in age while the other is Farmdalian.
As a weed, wheat has recently gained greater profile. Determining wheat persistence in cropping systems will facilitate the development of effective volunteer wheat management strategies. In October of 2000, glyphosate-resistant (GR) spring wheat seeds were scattered on plots at eight western Canada sites. From 2001 to 2003, the plots were seeded to a canola–barley–field-pea rotation or a fallow–barley–fallow rotation, with five seeding systems involving seeding dates and soil disturbance levels, and monitored for wheat plant density. Herbicides and tillage (in fallow systems) were used to ensure that no wheat plants produced seed. Seeding systems with greater levels of soil disturbance usually had greater wheat densities. Volunteer wheat densities at 2 (2002) and 3 (2003) yr after seed dispersal were close to zero but still detectable at most locations. At the end of 2003, viable wheat seeds were not detected in the soil seed bank at any location. The majority of wheat seedlings were recruited in the year following seed dispersal (2001) at the in-crop, prespray (PRES) interval. At the PRES interval in 2001, across all locations and treatments, wheat density averaged 2.6 plants m−2. At the preplanting interval (PREP), overall wheat density averaged only 0.2 plants m−2. By restricting density data to include only continuous cropping, low-disturbance direct-seeding (LDS) systems, the latter mean dropped below 0.1 plants m−2. Only at one site were preplanting GR wheat densities sufficient (4.2 plants m−2) to justify a preseeding herbicide treatment in addition to glyphosate in LDS systems. Overall volunteer wheat recruitment at all spring and summer intervals in the continuous cropping rotation in 2001 was 1.7% (3.3 plants m−2). Despite the fact that volunteer wheat has become more common in the central and northern Great Plains, there is little evidence from this study to suggest that its persistence will be a major agronomic problem.
The assumption of independence of irrelevant alternatives in a sequential contingent valuation format should be questioned. Statistically, most valuation studies treat nonindependence as a consequence of unobserved individual effects. Another approach is to consider an inferential process in which any particular choice is part of a general choosing strategy of a survey respondent. A stochastic model is suggested, consistent with the reflexivity, transitivity, and continuity axioms of utility analysis. An application of this theoretical model to the valuation of watershed ecosystem restoration demonstrates that an empirical model recognizing reflexivity and transitivity, and also allowing for continuity, shows the highest in-sample predictive ability.