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The political atmosphere on US college campuses is overwhelmingly left-leaning and liberal, with the vast majority of faculty self-identifying as socially progressive. Considerable research on cognitive biases has demonstrated the pervasive role of people’s attitudes, which act as filters during thinking and reasoning – particularly about politically-valenced topics. The prevalence of faculty from one side of the political spectrum coupled with the omnipresence of cognitive biases means that college campuses and the research done by their faculty runs the risk of favoring one side during what should, scientifically-speaking, be a process of fair and open inquiry. We discuss these phenomena and document numerous examples in which lack of genuine viewpoint diversity has spelled trouble for sound science. We advocate a more ideologically-diverse scientific workforce to better enable true diversity of thinking on key issues of our time.
There are large between-country differences in measures of economic and noneconomic well-being. Many researchers view increasing the stock of human capital as the key to raising economic development, promoting democratization, and improving health, and hence improving overall societal well-being. The single most studied aspect of human capital concerns cognitive competence. Differences in population cognitive competence might explain these societal differences. Evidence suggests that education builds cognitive competence, and education and cognitive competence promote better social outcomes, in terms of both economic and noneconomic factors. However, measuring population cognitive competence for countries requires representative samples, culture-fair tests, equivalency in the relationship between test measures and other cognitive attributes, and comparability in testing situations. In most cases, none of this has been achieved.
The Minnesota Center for Twin and Family Research (MCTFR) comprises multiple longitudinal, community-representative investigations of twin and adoptive families that focus on psychological adjustment, personality, cognitive ability and brain function, with a special emphasis on substance use and related psychopathology. The MCTFR includes the Minnesota Twin Registry (MTR), a cohort of twins who have completed assessments in middle and older adulthood; the Minnesota Twin Family Study (MTFS) of twins assessed from childhood and adolescence into middle adulthood; the Enrichment Study (ES) of twins oversampled for high risk for substance-use disorders assessed from childhood into young adulthood; the Adolescent Brain (AdBrain) study, a neuroimaging study of adolescent twins; and the Siblings Interaction and Behavior Study (SIBS), a study of adoptive and nonadoptive families assessed from adolescence into young adulthood. Here we provide a brief overview of key features of these established studies and describe new MCTFR investigations that follow up and expand upon existing studies or recruit and assess new samples, including the MTR Study of Relationships, Personality, and Health (MTR-RPH); the Colorado-Minnesota (COMN) Marijuana Study; the Adolescent Brain Cognitive Development (ABCD) study; the Colorado Online Twins (CoTwins) study and the Children of Twins (CoT) study.
This volume has achieved a large coverage of the experimentally well-studied areas of the temperate and subtropical coasts of the world (see Figure 1.1) – venturing into the tropics in some regions (Chapter 14, South-East Asia) and including mangroves (Chapter 17). Coral reef systems have not been considered. Much of the emphasis has been on rocky habitats as this is where the majority of experimental work on interactions has been done (but see Chapter 6). As well as reviewing regions where there has been a long history of experimental research (e.g., Chapters 2–4, 6, 10, 11, 13, 15, 16), areas of emerging experimental research in the last twenty-five years (e.g., Chapter 8, western Mediterranean; Chapter 12, south-east Pacific) and understudied regions (e.g., Chapter 7, Argentina; Chapter 14, South-East Asia) have also been included, allowing more comprehensive insights into the processes important for shaping these communities. In this short synthesis chapter, we first consider the main processes determining patterns covered by the previous chapters. We then consider major human impacts in these regions. Finally, we identify gaps in knowledge and make some suggestions for the way forward. We make the case for combining phylogeographic studies with macro-ecology and biogeography, coupled with well-designed hypothesis testing experiments, to better understand processes generating patterns on micro-evolutionary (hundreds to thousands of years) and ecological (up to hundreds of years) time scales.
The synthesis of the Aquatic Biodiversity and Ecosystems Conference (ABEC) 2015, which was held to assess scientific progress over the past twnety-five years, this book provides a comprehensive and global review of work since the 1992 publication of Plant-Animal Interactions in the Marine Benthos. Taking a regional and, where appropriate, habitat perspective, it considers sites of coastal biodiversity from around the world to incorporate a global approach. The volume analyses abiotic and biotic interactions, and the factors determining distribution patterns, community structure and ecosystem functioning of coastal systems. It explores themes of how phylogeography and biogeographic process influence assemblage composition, and hence drive community structure and the respective roles of environmental factors and biological interactions, with the overall goal to establish how general are the processes in different regions and habitats. For researchers, graduate students and academics studying coastal ecosystems, with interest for conservation practitioners managing areas of high biodiversity.
At the end of the 2015 Aquatic Biodiversity and Ecosystems Conference, a day was set aside for a workshop following up on the 1990 Plant–Animal Interactions meeting and its associated Systematics Association book – Plant–Animal Interactions in the Marine Benthos (John et al., 1992). Talks given throughout the 2015 conference also informed the present volume and its chapters. The 2015 workshop took a comparative approach with a series of informal presentations and discussion sessions from selected participants from around the world. The general aim was to take a regionally based view of the role of interactions in setting distribution patterns, community structure and functioning of shallow-water marine ecosystems. The coverage was predominantly coastal, down to the limit of light penetration. Most contributions were from those working on rocky intertidal and subtidal habitats, reflecting the size (and willingness to contribute) of the research community coupled with the greater tradition of experimental approaches to examine interactions on more tractable hard substrata. In addition, mangroves, biofilms and the deep sea were also considered as special systems that are ubiquitous across several oceans where significant advances have been made and, therefore, warranted inclusion. Recent advances in remotely operated vehicles, for example, have increased the scope for observation and experiment in the deep sea (Johnson et al., 2013); whereas mangroves are important ecosystem engineers which provide important ecosystem services, but are declining globally (Polidoro et al., 2010; Chee et al., 2017). Biofilms were also included as a subject given their global distribution and importance as the site of first settlement of macrobenthic organisms and as a food source for grazers (Abreu et al., 2007). While this volume does not feature any chapters specifically on artificial structures, ocean sprawl or eco-engineering, a large number of talks and posters at the conference dealt with these emerging issues, reflecting their global importance (see Firth et al., 2016; Bishop et al., 2017 and Strain et al., 2018 for reviews). A notable omission is coral reefs, which were not covered because they already have a well-established community of research workers and deserve a volume in their own right. Inevitably, there are gaps in coverage reflecting difficulties in soliciting and delivering input, especially on soft shores as well as certain geographic locations. Coverage in 1992 and 2018 is shown on the maps in Figure 1.1.
Much of the peace agreement durability literature assumes that stronger peace agreements are more likely to survive the trials of the post-conflict environment. This work does an excellent job identifying which provisions indicate that agreements are more likely to endure. However, there is no widely accepted way to directly measure the strength of agreements, and existing measures suffer from a lack of nuance or reliance on subjective weighting. We use a Bayesian item response theory model to develop a principled measure of the latent strength of peace agreements in civil conflicts from 1975 to 2005. We illustrate the measure's utility by exploring how various international factors such as sanctions and mediation contribute to the strength or weakness of agreements.
Radiocarbon (14C or carbon-14, half-life 5730 yr) is a key radionuclide in the assessment of the safety of a geological disposal facility (GDF) for radioactive waste. In particular, the radiological impact of gaseous carbon-14 bearing species has been recognized as a potential issue. Irradiated steels are one of the main sources of carbon-14 in the United Kingdom’s radioactive waste inventory. However, there is considerable uncertainty about the chemical form(s) in which the carbon-14 will be released. The objective of the work was to measure the rate and speciation of carbon-14 release from irradiated 316L(N) stainless steel on leaching under high-pH anoxic conditions, representative of a cement-based near field for low-heat generating wastes. Periodic measurements of carbon-14 releases to both the gas phase and to solution were made in duplicate experiments over a period of up to 417 days. An initial fast release of carbon-14 from the surface of the steel is observed during the first week of leaching, followed by a drop in the rate of release at longer times. Carbon-14 is released primarily to the solution phase with differing fractions released to the gas phase in the two experiments: about 1% of the total release in one and 6% in the other. The predominant dissolved carbon-14 releases are in inorganic form (as 14C-carbonate) but also include organic species. The predominant gas-phase species are hydrocarbons with a smaller fraction of 14CO (which may include some volatile oxygen-containing carbon-species). The experiments are continuing, with final sampling and termination planned after leaching for a total of two years.
We use deep Chandra and HST data to uniquely classify the X-ray binary (XRB) populations in M81 on the basis of their donor stars and local stellar populations (into early-type main sequence, yellow giant, supergiant, low-mass, and globular cluster). First, we find that more massive, redder, and denser globular clusters are more likely to be associated with XRBs. Second, we find that the high-mass XRBs (HMXBs) overall have a steeper X-ray luminosity function (XLF) than the canonical star-forming galaxy XLF, though there is some evidence of variations in the slopes of the sub-populations. On the other hand, the XLF of the prototypical starburst M82 is described by the canonical powerlaw (αcum ∼ 0.6) down to LX ∼ 1036 erg s−1. We attribute variations in XLF slopes to different mass transfer modes (Roche-lobe overflow versus wind-fed systems).
We analyse the vertical distribution of High Mass X-ray Binaries (HMXBs) in NGC 55, the nearest edge-on galaxy to the Milky Way. Our analysis reveals significant spatial offsets of HMXBs from the star forming regions, greater than those observed in the SMC and the LMC but similar with the Milky Way. The spatial offsets can be explained by a momentum kick the X-ray binaries receive during the formation of the compact object. The difference between the scale height of the vertical distribution of HMXBs and the vertical distribution of star-forming activity is 0.48±0.04 kpc. The centre-of-mass velocity of the distribution of HMXBs in NGC 55 is moving at a velocity of 52.4±11.4 km s−1, greater than the corresponding velocity of HMXBs in the SMC and LMC, but consistent with velocities of Milky Way HMXBs.
To evaluate probiotics for the primary prevention of Clostridium difficile infection (CDI) among hospital inpatients.
A before-and-after quality improvement intervention comparing 12-month baseline and intervention periods.
A 694-bed teaching hospital.
We administered a multispecies probiotic comprising L. acidophilus (CL1285), L. casei (LBC80R), and L. rhamnosus (CLR2) to eligible antibiotic recipients within 12 hours of initial antibiotic receipt through 5 days after final dose. We excluded (1) all patients on neonatal, pediatric and oncology wards; (2) all individuals receiving perioperative prophylactic antibiotic recipients; (3) all those restricted from oral intake; and (4) those with pancreatitis, leukopenia, or posttransplant. We defined CDI by symptoms plus C. difficile toxin detection by polymerase chain reaction. Our primary outcome was hospital-onset CDI incidence on eligible hospital units, analyzed using segmented regression.
The study included 251 CDI episodes among 360,016 patient days during the baseline and intervention periods, and the incidence rate was 7.0 per 10,000 patient days. The incidence rate was similar during baseline and intervention periods (6.9 vs 7.0 per 10,000 patient days; P=.95). However, compared to the first 6 months of the intervention, we detected a significant decrease in CDI during the final 6 months (incidence rate ratio, 0.6; 95% confidence interval, 0.4–0.9; P=.009). Testing intensity remained stable between the baseline and intervention periods: 19% versus 20% of stools tested were C. difficile positive by PCR, respectively. From medical record reviews, only 26% of eligible patients received a probiotic per the protocol.
Despite poor adherence to the protocol, there was a reduction in the incidence of CDI during the intervention, which was delayed ~6 months after introducing probiotic for primary prevention.
In Australia, Aboriginal and Torres Strait Islander people score poorly on national mainstream indicators of wellbeing, with the lowest outcomes recorded in remote communities. As part of a ‘shared space’ collaboration between remote Aboriginal communities, government and scientists, the holistic Interplay Wellbeing Framework and accompanying survey were designed bringing together Aboriginal priorities of culture, empowerment and community with government priorities of education, employment and health. Quantitative survey data were collected from a cohort of 841 Aboriginal people aged 15–34 years, from four different Aboriginal communities. Aboriginal community researchers designed and administered the survey. Structural equation modelling was used to identify the strongest interrelating pathways within the framework. Optimal pathways from education to employment were explored with the concept of empowerment playing a key role. Here, education was defined by self-reported English literacy and numeracy and empowerment was defined as identity, self-efficacy and resilience. Empowerment had a strong positive impact on education (β = 0.38, p < .001) and strong correlation with employment (β = 0.19, p < .001). Education has a strong direct effect on employment (β = 0.40, p < .001). This suggests that education and employment strategies that foster and build on a sense of empowerment are mostly likely to succeed, providing guidance for policy and programs.
Recent droughts in Puerto Rico and throughout the Caribbean have emphasized the region's agricultural vulnerability to this hazard and the increasing need for adaptation mechanisms to support sustainable production. In this study, we assessed the geographic extent of agricultural conservation practices incentivized by US Department of Agriculture Natural Resources Conservation Service (NRCS) and evaluated their large-scale contribution to drought adaptability. We identified concentrations of drought-related practices (e.g. cover crops, ponds) applied between 2000 and 2016. Using information from spatial databases and interviews with experts, we assessed the spatial correlation between these practices and areas exposed to drought as identified by the US Drought Monitor. Between 2000 and 2016, Puerto Rico experienced seven drought episodes concentrated around the south, east and southeastern regions. The most profound drought occurred between 2014 and 2016 when the island experienced 80 consecutive weeks of moderate drought, 48 of severe drought and 33 of extreme drought conditions. A total of 44 drought-related conservation practices were applied at 6984 locations throughout 860 km2 of farmlands between 2000 and 2016 through the NRCS-Environmental Quality Incentives Program (EQIP). Practices related to water availability were statistically clustered along the coasts, whereas soil and plant health practices were clustered in the mountainous region. While these concentrations strongly correlated with areas exposed to moderate drought conditions, >80% did not coincide with areas that experienced severe or extreme drought conditions, suggesting that areas highly exposed to drought conditions generally lacked drought preparedness assisted by EQIP. Climate projections indicate an increase in the frequency and intensity of drought events, particularly in the eastern region of Puerto Rico. Our analysis highlighted the need to implement more conservation practices in these areas subject to drought intensification and exposure. Government programs intended to address vulnerabilities and enhance capacity and resilience may not be reaching areas of highest exposure. Recommendations include raising producer awareness of past and future exposure and making programs more accessible to a broader audience.