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The rise of “fake news” is a major concern in contemporary Western democracies. Yet, research on the psychological motivations behind the spread of political fake news on social media is surprisingly limited. Are citizens who share fake news ignorant and lazy? Are they fueled by sinister motives, seeking to disrupt the social status quo? Or do they seek to attack partisan opponents in an increasingly polarized political environment? This article is the first to test these competing hypotheses based on a careful mapping of psychological profiles of over 2,300 American Twitter users linked to behavioral sharing data and sentiment analyses of more than 500,000 news story headlines. The findings contradict the ignorance perspective but provide some support for the disruption perspective and strong support for the partisan polarization perspective. Thus, individuals who report hating their political opponents are the most likely to share political fake news and selectively share content that is useful for derogating these opponents. Overall, our findings show that fake news sharing is fueled by the same psychological motivations that drive other forms of partisan behavior, including sharing partisan news from traditional and credible news sources.
Pregnant individuals who overeat are more likely to predispose their fetus to the development of metabolic disorders in adulthood. Physical training is a prevention and treatment interventional strategy that could treat these disorders, since it improves metabolism and body composition. This study assessed the protective effect of physical exercise against possible metabolic changes in generations F1 and F2, whose mothers were subjected to a high-sugar/high-fat (HS/HF) diet. Wistar rats belonging to generation F0 were distributed into four groups (n = 10): sedentary control (CSed), exercised control (CExe), sedentary HS/HF diet (DHSed) and exercised HS/HF diet (DHExe). From 21 to 120 days of age, maintained during pregnancy and lactation period, CSed/CExe animals received standard feed and DHSed/DHExe animals a HS/HF diet. Animals from the CExe/DHExe underwent physical training from 21 to 120 days of age. Male and female F1 and F2 received a normocaloric feed and did not perform any physical training, categorized into four groups (n = 10) according to the maternal group to which they belonged to. An increase in body weight, adiposity and glucose, and a change in lipid profile in F0 were observed, while exercise reduced the biochemical parameters comparing DHSed with DHExe. Maternal exercise had an effect on future generations, reducing adiposity, glucose and triglyceride concentrations, and preventing deleterious effects on glucose tolerance. Maternal overeating increased health risks both for mother and offspring, demonstrating that an HS/HF diet intake promotes metabolic alterations in the offspring. Importantly, the physical training performed by F0 proved to be protective against such effects.
The aim of our article was to review the current literature on the effects of metabolic (re) programming on childhood obesity. PubMed/MEDLINE was the data source used to track the studies. Descriptors applied: children obesity, epigenetic, metabolic programming, exercise and nutrition. The focus was to analyze and discuss the international findings on the theme. The gathering of the papers was performed between June and August 2014. The search of articles with the descriptors used found 33.054 studies. In all, 5.709 studies were selected by crossing chosen keywords. Among these, after careful reading of the titles, 712 papers were considered potential as references. After applying inclusion/exclusion criteria, 50 studies were selected from 132 eligible abstracts. Most studies linked the development and treatment of obesity from epigenetically stimulated metabolic programming during the early stages of pregnancy and life. This review provides theoretical basis to the understanding that the programmed development of childhood obesity may be linked to early exposure to environmental factors, such as (nutrition and regular practice of exercise) and stimulus can epigenetically alter the modulation of the obesogenic metabolic behavior during pregnancy and the developmental stages of children and/or postpone the pathophysiologic disease stage to adulthood.
The nucleation, growth and coarsening of carbides is investigated in high niobium containing TiAl alloys by diffraction and transmission electron microscopy. Higher carbon content increases the dissolution temperature of carbides. The solubility of carbon is much higher in a γ/α2-phase alloy than in the γ phase alone. Hereby no significant influence of Nb on carbon solubility is found. Crystallographic defects as grain boundaries and dislocations promote carbide nucleation which results in a carbide precipitation sequence starting first at grain boundaries, then at dislocations and only later in the γ matrix away from crystallographic defects. The consumption of carbon by grain boundary carbides or neighboring α2 grains also generates a precipitate free zone in γ grains near the grain boundary.
Vitamin A supplementation (VAS) at birth was not associated with improved survival in a randomised, placebo-controlled trial in Guinea-Bissau. However, a negative sex-differential effect, which became evident after diphtheria–tetanus–pertussis (DTP) vaccination, was noted; among girls who had received DTP, VAS at birth was associated with two-fold higher mortality than placebo. The objective of the present study was to investigate the immunological effects of VAS at birth within a subgroup of participants in the randomised trial. Guided by the mortality results, we further explored whether VAS had a differential effect according to sex and DTP status. At 6 weeks after randomisation and supplementation, we measured differential leucocyte counts and TNF-α, interferon-γ, IL-10, IL-13 and IL-5 production in a whole-blood culture assay. A total of 471 children were included. VAS compared with placebo at birth was associated with a higher proportion of monocytes (relative risk ratio 1·26, 95 % CI 1·07, 1·49, P= 0·04), while spontaneous TNF-α production was lower in the VAS group (geometric mean ratio 0·54, 95 % CI, 0·37, 0·78, P= 0·001). Stratified analysis showed that VAS was associated with lower TNF-α and IL-10 production for girls without DTP and boys with DTP, resulting in significant three-way interactions between VAS, sex and DTP vaccination status (P= 0·03 and P= 0·04, respectively) for spontaneous TNF-α and IL-10 production. The results substantiate the potential role of VAS as an immunomodulatory intervention, which has different effects depending on concomitant health interventions and the sex of the recipient.
We find problems with Vaesen's treatment of the primatological research, in particular his analysis of foresight, function representation, and social intelligence. We argue that his criticism of research on foresight in great apes is misguided. His claim that primates do not attach functions to particular objects is also problematic. Finally, his analysis of theory of mind neglects many distinctions.
What are the significant forces behind the evolution of language?
Explaining how language evolved involves answering two quite distinct scientific questions (Bickerton 2003; Tomasello 2003). The first is why humans have developed a system of symbolic representation as a basis for much of their communication. The second is why this system has acquired the structural characteristics of the syntax of extant human languages. In this paper, we focus on the first question.
Homo sapiens is the only species we know to have a symbolic language. If one believes that language has come into existence according to the principles of evolutionary theory, there should be some selective advantage that has promoted the development of language among humans. Recently, a popular approach has been that language arose as a result of increased social interaction, for example as a consequence of increasing group size (Dunbar 1996) or as some form of ritualization (Deacon 1997; Knight 1998b).
However, despite all the merits of these proposals, they have problems explaining why humanlike symbolic language has not evolved among other apes or animals (Bickerton 2002: 209; Gärdenfors 2004: 237; Johansson, Zlatev, and Gärdenfors 2006). As a matter of fact, the social interaction among many species is highly developed. Bickerton (2002: 210) argues: “When a complex and unique development occurs in only one species, the most logical conclusion is that the selective pressure driving that development must have been unique to that species.
The proliferation of the voluntarily-introduced cupped oyster, Crassostrea gigas, has attained the proportions of species invasion in many intertidal habitats in Europe, presumably resulting from successful reproduction of farmed individuals. It is thus imperative to better understand the reproductive characteristics of farmed oysters, since they are directly under human
control. We quantified the dry tissue mass (DTM), gametosomatic index (GSI),
and reproductive cycle of farmed oysters at two sites in Bourgneuf Bay,
France, in relation to environmental parameters using continuously-recording
probes in 2005 and 2006. The GSI was developed for this study, based on the
actual area occupied by gametes, rather than the area of the gonad
previously used for quantitative histological estimation of reproductive
effort. The two sites, intermediate – (IT) and high-turbidity (HT), differed
markedly in the amount and quality of particulate suspended matter, and also
in fine-scale temperature variations. Oysters at both sites presented two
spawning periods in both 2005 and 2006; Bourgneuf Bay is thus near the
northernmost European limit for a 2-spawning cycle in Crassostrea gigas. Gonad maturation was initiated when spring water temperature reached 8–10 °C, and gamete
atresia occurred when water temperatures transiently dipped to 15–18 °C.
Spawns, which occurred above 18 °C, were timed by fine-scale water
temperature variations. Particulate organic matter quality peaks, coinciding
with gonad maturation, were related to DTM variations before spawning
periods, for the IT oysters in both years, and for the HT oysters in 2006.
The reproductive effort (GSI) of oysters was similar at both sites; however,
the fates of the gametes differed according to site. At the first spawning,
the IT oyster gamete emissions were +1 month delayed, as were peak water
temperatures greater than 18 °C, and more pronounced, compared to the HT
site. Although the second spawning showed high proportions of atretic
oocytes at both sites in both years, the IT oysters evacuated twice as many
gametes as the HT oysters in 2005. The IT conditions therefore appear more
suited to Crassostrea gigas gamete evacuation than the HT conditions.
The paper reviews the basics of SiC bulk growth by the physical vapor transport (PVT) method and discuss current and possible future concepts to improve crystalline quality. In-situ process visualization using x-rays, numerical modeling and advanced doping techniques will be briefly presented which support growth process optimization. The “pure” PVT technique will be compared with related developments like the so called Modified-PVT, Continuous-Feeding-PVT, High-Temperature-CVD and Halide-CVD concepts. Special emphasis will be put on dislocation generation and annihilation and concepts to reduce dislocation density during SiC bulk crystal growth. The dislocation study is based on a statistical approach. Rather than following the evolu-tion of a single defect, statistic data which reflect a more global dislocation density evolution are interpreted. In this context a new approach will be presented which relates thermally induced strain during growth and dislocation patterning in networks.
We are not entirely satisfied with the evolutionary explanation provided by Suddendorf & Corballis (S&C) for why only humans should be capable of advanced mental time travel. General social factors do not suffice, given that other primates are also highly social. We discuss the evolutionary mechanisms that have generated mental time travel typical to humans, focusing on ecological factors.
There is very much more to Daniel Defoe's inspired piece of ‘faction’ about Robinson Crusoe than seeing it just as a boy's adventure story. Its influence was widespread, judging by the great scale of new editions and reprintings, both internationally and through many translations. It can be read as a sophisticated myth of the ascent of man, of economic growth by dint of the work ethic, of the imperative of ‘improvement’ and the determination to master nature. It has implications for natural rights theory, the Lockeian justification of private property and the role of the ‘civilised’ European facing a hostile, alien habitat.
A calibration procedure for the detection efficiency of energy
dispersive X-ray spectrometers (EDS) used in combination with scanning
electron microscopy (SEM) for standardless electron probe microanalysis
(EPMA) is presented. The procedure is based on the comparison of X-ray
spectra from a reference material (RM) measured with the EDS to be
calibrated and a reference EDS. The RM is certified by the line
intensities in the X-ray spectrum recorded with a reference EDS and by its
composition. The calibration of the reference EDS is performed using
synchrotron radiation at the radiometry laboratory of the
Physikalisch-Technische Bundesanstalt. Measurement of RM spectra and
comparison of the specified line intensities enables a rapid efficiency
calibration on most SEMs. The article reports on studies to prepare such a
RM and on EDS calibration and proposes a methodology that could be
implemented in current spectrometer software to enable the calibration
with a minimum of operator assistance.