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New radiocarbon (14C) dates suggest a simultaneous appearance of two technologically and geographically distinct axe production practices in Neolithic Britain; igneous open-air quarries in Great Langdale, Cumbria, and from flint mines in southern England at ~4000–3700 cal BC. In light of the recent evidence that farming was introduced at this time by large-scale immigration from northwest Europe, and that expansion within Britain was extremely rapid, we argue that this synchronicity supports this speed of colonization and reflects a knowledge of complex extraction processes and associated exchange networks already possessed by the immigrant groups; long-range connections developed as colonization rapidly expanded. Although we can model the start of these new extraction activities, it remains difficult to estimate how long significant production activity lasted at these key sites given the nature of the record from which samples could be obtained.
Problems involving image segmentation, atomic cluster identification, segmentation of microstructure constituents in images and austenite reconstruction have seen various approaches attempt to solve them with mixed results. No single computational technique has been able to effectively tackle these problems due to the vast differences between them. We propose the application of graph cutting as a versatile technique that can provide solutions to numerous materials data analysis problems. This can be attributed to its configuration flexibility coupled with the ability to handle noisy experimental data. Implementation of a Bayesian statistical approach allows for the prior information, based on experimental results and already ingrained within nodes, to drive the expected solutions. This way, nodes within the graph can be grouped together with similar, neighboring nodes that are then assigned to a specific system with respect to calculated likelihoods. Associating probabilities with potential solutions and states of the system allows for quantitative, stochastic analysis. The promising, robust results for each problem indicate the potential usefulness of the technique so long as a network of nodes can be effectively established within the model system.
The Stac Fada Member of the Stoer Group, within the Torridonian succession of NW Scotland, is a melt-rich, impact-related deposit that has not been conclusively correlated with any known impact structure. However, a gravity low approximately 50 km east of the preserved Stac Fada Member outcrops has recently been proposed as the associated impact site. We investigate the location of the impact structure through a provenance study of detrital zircon and apatite in five samples from the Stoer Group. Our zircon U–Pb data are dominated by Archaean grains (> 2.5 Ga), consistent with earlier interpretations that the detritus was largely derived from local Lewisian Gneiss Complex, whereas the apatite data (the first for the Stoer Group) display a single major peak at c. 1.7 Ga, consistent with regional Laxfordian metamorphism. The almost complete absence of Archaean-aged apatite is best explained by later heating of the > 2.5 Ga Lewisian basement (the likely source region) above the closure temperature of the apatite U–Pb system (c. 375–450°C). The U–Pb age distributions for zircon and apatite show no significant variation with stratigraphic height. This may be interpreted as evidence that there was no major change in provenance during the course of deposition of the Stoer Group or, if there was any significant change, the different source regions were characterized by similar apatite and zircon U–Pb age populations. Consequently, the new data do not provide independent constraints on the location of the structure associated with the Stac Fada Member impact event.
Environmental and biological factors contribute to sleep development during infancy. Parenting plays a particularly important role in modulating infant sleep, potentially via the serotonin system, which is itself involved in regulating infant sleep. We hypothesized that maternal neglect and serotonin system dysregulation would be associated with daytime sleep in infant rhesus monkeys. Subjects were nursery-reared infant rhesus macaques (n = 287). During the first month of life, daytime sleep-wake states were rated bihourly (0800–2100). Infants were considered neglected (n = 16) if before nursery-rearing, their mother repeatedly failed to retrieve them. Serotonin transporter genotype and concentrations of cerebrospinal fluid 5-hydroxyindoleacetic acid (5-HIAA) were used as markers of central serotonin system functioning. t tests showed that neglected infants were observed sleeping less frequently, weighed less, and had higher 5-HIAA than non-neglected nursery-reared infants. Regression revealed that serotonin transporter genotype moderated the relationship between 5-HIAA and daytime sleep: in subjects possessing the Ls genotype, there was a positive correlation between 5-HIAA and daytime sleep, whereas in subjects possessing the LL genotype there was no association. These results highlight the pivotal roles that parents and the serotonin system play in sleep development. Daytime sleep alterations observed in neglected infants may partially derive from serotonin system dysregulation.
Here we present the synthesis of porous platinum–palladium macrobeams templated from high aspect ratio Magnus’ salt needle derivatives. The combination of [PtCl4]2− and/or [PdCl4]2− with [Pt(NH3)4]2+ ions results in salt needles ranging from 15 to 300 µm in length. Electrochemical reduction of the salt templates results in porous macrobeams with a square cross-section. Porous side wall texture and elemental composition was controlled with initial platinum to palladium salt ratio. Macrobeam free-standing films exhibited a specific capacitance up to 11.73 F/g and a solvent accessible surface area of 26.6 m2/g. These salt-templated porous platinum–palladium macrobeams offer a promising material for fuel cell catalysis.
Ondansetron is increasingly administered to children suffering from concussion-associated nausea/vomiting. We examined the association between ondansetron administration and post-concussion symptoms in children at 1 week and 1 month following the concussion.
This was a secondary analysis of data collected prospectively in a cohort study conducted in nine pediatric emergency departments (EDs) (5P study). Participants were children ages between 5 and 17.99 years who sustained a concussion in the previous 48 hours. For the current study, only 5P participants who reported nausea and/or vomiting in the ED were eligible. The exposure of interest was ondansetron administration; the comparison group included all other participants. The primary outcome was an increase in at least three symptoms of the Post-Concussion Symptom Inventory score at 1 week and 1 month following trauma.
Among the 3,063 children included in the 5P study, 1805 (59%) reported nausea and provided data at 1 week and/or 1 month. Among them, 132 (7%) received ondansetron. Multivariable logistic regression adjusted for confounders did not show an association between ondansetron use and the risk of persistent post-concussion symptoms at 1 week (OR: 1.13 [95% CI: 0.86-1.49]), but it was associated with a higher risk at 1 month (OR: 1.33 [95% CI: 1.05-1.97]).
In children presenting to the ED with an acute concussion, ondansetron use was associated with a higher risk of persistent post-concussion symptoms at 1 month. Although this may be related to the limitations of the design, it highlights the importance of evaluating this association using a randomized clinical trial.
This paper highlights major developments over the past two to three decades in the neuropsychology of movement and its disorders. We focus on studies in healthy individuals and patients, which have identified cognitive contributions to movement control and animal work that has delineated the neural circuitry that makes these interactions possible. We cover advances in three major areas: (1) the neuroanatomical aspects of the “motor” system with an emphasis on multiple parallel circuits that include cortical, corticostriate, and corticocerebellar connections; (2) behavioral paradigms that have enabled an appreciation of the cognitive influences on the preparation and execution of movement; and (3) hemispheric differences (exemplified by limb praxis, motor sequencing, and motor learning). Finally, we discuss the clinical implications of this work, and make suggestions for future research in this area. (JINS, 2017, 23, 768–777)
A number of laser facilities coming online all over the world promise the capability of high-power laser experiments with shot repetition rates between 1 and 10 Hz. Target availability and technical issues related to the interaction environment could become a bottleneck for the exploitation of such facilities. In this paper, we report on target needs for three different classes of experiments: dynamic compression physics, electron transport and isochoric heating, and laser-driven particle and radiation sources. We also review some of the most challenging issues in target fabrication and high repetition rate operation. Finally, we discuss current target supply strategies and future perspectives to establish a sustainable target provision infrastructure for advanced laser facilities.
Cryptosporidium parvum is the major cause of livestock and zoonotically-acquired human cryptosporidiosis. The ability to track sources of contamination and routes of transmission by further differentiation of isolates would assist risk assessment and outbreak investigations. Multiple-locus variable-number of tandem-repeats (VNTR) analysis provides a means for rapid characterization by fragment sizing and estimation of copy numbers, but structured, harmonized development has been lacking for Cryptosporidium spp. To investigate potential for application in C. parvum surveillance and outbreak investigations, we studied nine commonly used VNTR loci (MSA, MSD, MSF, MM5, MM18, MM19, MS9-Mallon, GP60 and TP14) for chromosome distribution, repeat unit length and heterogeneity, and flanking region proximity and conservation. To investigate performance in vitro, we compared these loci in 14 C. parvum samples by capillary electrophoresis in three laboratories. We found that many loci did not contain simple repeat units but were more complex, hindering calculations of repeat unit copy number for standardized reporting nomenclature. However, sequenced reference DNA enabled reproducible fragment sizing and inter-laboratory allele assignation based on size normalized to that of the sequenced fragments by both single round and nested polymerase chain reactions. Additional Cryptosporidium loci need to be identified and validated for robust inter-laboratory surveillance and outbreak investigations.
Objectives: The purpose of this study was to assess whether age-related differences in white matter microstructure are associated with altered task-related connectivity during episodic recognition. Methods: Using functional magnetic resonance imaging and diffusion tensor imaging from 282 cognitively healthy middle-to-late aged adults enrolled in the Wisconsin Registry for Alzheimer’s Prevention, we investigated whether fractional anisotropy (FA) within white matter regions known to decline with age was associated with task-related connectivity within the recognition network. Results: There was a positive relationship between fornix FA and memory performance, both of which negatively correlated with age. Psychophysiological interaction analyses revealed that higher fornix FA was associated with increased task-related connectivity amongst the hippocampus, caudate, precuneus, middle occipital gyrus, and middle frontal gyrus. In addition, better task performance was associated with increased task-related connectivity between the posterior cingulate gyrus, middle frontal gyrus, cuneus, and hippocampus. Conclusions: The findings indicate that age has a negative effect on white matter microstructure, which in turn has a negative impact on memory performance. However, fornix microstructure did not significantly mediate the effect of age on performance. Of interest, dynamic functional connectivity was associated with better memory performance. The results of the psychophysiological interaction analysis further revealed that alterations in fornix microstructure explain–at least in part–connectivity among cortical regions in the recognition memory network. Our results may further elucidate the relationship between structural connectivity, neural function, and cognition. (JINS, 2016, 22, 191–204)
Sustainability, culture change, inequality and global health are among the much-discussed challenges of our time, and rightly so, given the drastic effects such variables can have on modern populations. Yet with many populations today living in tightly connected geographic communities—cities, for example—or in highly networked electronic communities, can we still learn anything about societal challenges by studying simple farming communities from many thousands of years ago? We think there is much to learn, be it Malthusian pressures and ancient societal collapse, the devastating effects of European diseases on indigenous New World populations or endemic violence in pre-state societies (e.g. Pinker 2012). By affording a simpler, ‘slow motion’ view of processes that are greatly accelerated in this century, the detailed, long-term record of the European Neolithic can offer insight into many of these fundamental issues. These include: human adaptations to environmental change (Palmer & Smith 2014), agro-pastoral innovation, human population dynamics, biological and cultural development, hereditary inequality, specialised occupations and private ownership.
The Stanford Prison Experiment (SPE) is widely recognized as one of the most ethically controversial psychology studies ever conducted. In 1971, 24 college students who had volunteered to take part in a “psychological study of prison life” were randomly assigned to roles as guards and prisoners within a “prison” that had been specially constructed in the basement of the Stanford University psychology department. As most psychology students would be aware, the study had to be brought to a premature close after six days due to the intense distress that the prisoners were experiencing at the hand of the guards. At the time, the ethical framework for conducting research of this form was poorly defined and relatively informal. But partly as a consequence of the horrors it led to, after the SPE, psychologists’ code of research ethics was formalized and tightened, with the result that many felt it would never again be possible to conduct studies of this form.
Despite – or perhaps because of – this, since it was conducted, the SPE has exerted a vice-like grip over discussions about the issues of tyranny and evil that it investigated. This means that when reflecting on large-scale human atrocity, it is commonplace for researchers and commentators alike to reprise the argument that this reflects people’s “natural” tendency to conform uncritically to the specifications of any group roles they are assigned, however noxious they might be. This in itself is of major ethical concern, potentially letting perpetrators off the hook. Thus, if conducting studies like the SPE raises serious ethical issues, not conducting them is equally of ethical concern.
Chapter 6 has argued that workers responded to changes in real wage rates by adapting how hard they worked so as to maintain their earnings. Household incomes therefore tracked GDP per head rather than real wage rates and progressively improved over time, doubling between the early fourteenth and late seventeenth centuries and doubling again over the course of the industrial revolution. Higher incomes translated into changing patterns of consumption and the forms these consumption choices took are the subjects of this chapter. Section 7.2 reconstructs the kilocalorie value and composition of diets based on the agricultural-output estimates presented in Chapter 3, augmented by information on imported foodstuffs. Given that populations require an average daily food intake per head of 2,000 kilocalories (Livi-Bacci, 1991: 27) to provide sufficient nourishment for both economic and biological reproduction, these calculations also provide a useful cross-check on the consistency of the agricultural-output and population estimates. Section 7.3 then considers non-food consumption drawing upon early modern evidence of material culture as revealed by probate inventories. Again, these trends need to be consistent with those of industrial output reconstructed in Chapter 4.
Price, habit, fashion and status all shaped the budgetary decisions taken by households. Demand for food was inelastic up to the point where basic subsistence needs had been met, but as incomes rose there were clear trade-offs to be obtained between increasing consumption of cheap sources of kilocalories such as pottage, potatoes and salted herrings on the one hand, or indulging in more expensive refined bread, quality ale and beer, dairy produce and meat, plus the imported luxuries of wine, sugar, tea, cocoa and tobacco, on the other. In effect, higher incomes allowed more households to trade up to a respectability basket of foodstuffs providing a more varied and processed diet but not necessarily more kilocalories. The changing relative prices of arable, livestock and luxury products influenced these consumption decisions, while the relative cheapness or dearness of food determined how much disposable income could be devoted to the increasingly varied and tempting array of non-food consumer goods (Figure 5.02).