UCL University College London Eprints
UCL Eprints collects the work of UCL researchers and makes it freely available over the web, helping the worldwide scholarly community to discover UCL research. Institutional repositories like UCL Eprints complement the traditional academic publishing and scholarly communications processes. They raise the visibility of research and help to maximise its impact. UCL researchers are encouraged to deposit a copy of each journal article, conference paper, working paper, and any other research output, in the UCL Eprints at the earliest opportunity, ensuring that their research reaches as wide an audience as possible.
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The influence of puberty on subcortical brain development - Goddings, A-L; Viner, RM; Mills, KL; Blakemore, S-J; Clasen, LS; Giedd, JN
Puberty is characterized by hormonal, physical and psychological transformation. The human brain undergoes significant changes between childhood and adulthood, but little is known about how puberty influences its structural development. Using a longitudinal sample of 711 magnetic resonance imaging scans from 275 individuals aged 7-20. years, we examined how subcortical brain regions change in relation to puberty. Our regions of interest included the amygdala, hippocampus and corpus striatum including the nucleus accumbens (NA), caudate, putamen and globus pallidus (GP). Pubertal development was significantly related to structural volume in all six regions in both sexes. Pubertal development and age had both...
Increased functional connectivity with puberty in the mentalising network involved in social emotion processing. - Klapwijk, ET; Goddings, AL; Burnett Heyes, S; Bird, G; Viner, RM; Blakemore, SJ
This article is part of a Special Issue "Puberty and Adolescence". There is increasing evidence that puberty plays an important role in the structural and functional brain development seen in adolescence, but little is known of the pubertal influence on changes in functional connectivity. We explored how pubertal indicators (salivary concentrations of testosterone, oestradiol and DHEA; pubertal stage; menarcheal status) relate to functional connectivity between components of a mentalising network identified to be engaged in social emotion processing by our prior work, using psychophysiological interaction (PPI) analysis. Female adolescents aged 11 to 13years were scanned whilst silently reading scenarios designed...
Normal hearing in a child with the m.1555A>G mutation despite repeated exposure to aminoglycosides. Has the penetrance of this pharmacogenetic interaction been overestimated? - Al-Malky, G; Dawson, SJ; Suri, R; Sirimanna, T
The mtDNA m.1555A>G mutation causes increased susceptibility to aminoglycoside ototoxicity resulting in significant hearing loss in 100% of reported exposed cases. Genetic and audiological assessments were conducted in a sample of 59 children with cystic fibrosis (CF) undergoing aminoglycoside treatment. Of the two m.1555G patients identified one had severe-profound deafness. Surprisingly, the second m.1555G patient exhibited well-preserved hearing despite repeated exposure. This may be a rare case of intact hearing in an m.1555G individual with aminoglycoside use. Alternatively, its penetrance may have been previously overestimated due to recruitment bias. Further studies are required to determine the true penetrance to inform...
Major types of cardiovascular diseases and cognitive function: A review of patient and population-based investigations - Rafnsson, SB
Cognitive function is a critical dimension of the health of older people. Age-associated decline in cognitive function may be related to systemic diseases, including cardiovascular diseases (CVD). For example, a number of studies have examined cognitive function following the onset of stroke. In both patient and population-based studies, high rates of post-stroke cognitive impairment have frequently been observed although aspects of the event itself, including the type, laterality, and location, may influence the extent of possible cognitive recovery. In several studies, stroke patients have been found to perform worse on cognitive tests compared to stroke-free controls. For example, there is...
Can magnetopause reconnection drive Saturn's magnetosphere? - Masters, A; Fujimoto, M; Hasegawa, H; Russell, CT; Coates, AJ; Dougherty, MK
While solar wind-driven compression of Saturn's magnetosphere is an important trigger of magnetospheric dynamics, the importance of magnetopause reconnection has been the subject of debate. Here we use Cassini observations at Saturn's magnetopause to address this open issue. Measured conditions at the boundary suggest a typical reconnection electric field strength of order 0.01mVm. Although the strongest reconnection electric fields correspond to a compressed magnetosphere, compressed conditions do not guarantee a relatively strong reconnection electric field at the magnetopause location sampled by the spacecraft. By considering northward Interplanetary Magnetic Field (IMF), we predict reconnection voltages (open magnetic flux production rates) for...
Basaltic diversity at the Apollo 12 landing site: Inferences from petrologic examinations of the soil sample 12003 - Snape, JF; Joy, KH; Crawford, IA; Alexander, L
A detailed petrologic survey has been made of 17 basaltic chips (sized between 1 and 10 mm) from the 12003 soil sample as part of an ongoing study of basaltic diversity at the Apollo 12 landing site. An attempt has been made to classify these samples according to the well-established grouping of olivine, pigeonite, ilmenite, and feldspathic basalts. Particular attention has been paid to variations in major, minor, and trace element mineral chemistry (determined by electron microprobe analysis and laser ablation ICP-MS), which may be indicative of particular basaltic suites and less susceptible to sampling bias than bulk sample characteristics....
To what extent are women free to choose where to give birth? How discourses of risk, blame and responsibility influence birth place decisions - Coxon, K; Sandall, J; Fulop, NJ
Over the past 50 years, two things have changed for women giving birth in high-income nations; birth has become much safer, and now takes place in hospital rather than at home. The extent to which these phenomena are related is a source of ongoing debate, but concern about high intervention rates in hospitals, and financial pressures on health care systems, have led governments, clinicians and groups representing women to support a return to birth in 'alternative' settings such as midwife-led birth centres or at home, particularly for well women with healthy pregnancies. Despite this, most women still plan to give...
Judicial culture and social complexity: A general model from Anglo-Saxon England - Reynolds, A
The development of so-called 'complex societies' is a central concern of social science, and a theme to which the discipline of archaeology has made perhaps the most significant contributions with regard to the origins and earlier development of social systems in past societies. Almost all of the features that are widely accepted as indicators of social complexity - urbanism, social hierarchy, organized religion and so on - have been characterized and placed in sequence principally through the lens of physical evidence. That other fundamental feature of complex societies - writing - provides the most accessible view of yet another key...
Accuracy of exterior orientation for a range camera - Boehm, J; Pattinson, T
While known in principle for over 10 years range cameras have recently received increased attention. As the technology matures, interest is given to the possible applications of such sensors. Clearly the applicability of the sensor is connected to its reliability and accuracy. At the centre of this study lies the question how accurately the exterior orientation of a range camera can be estimated, given a reference point cloud. Before we can assess the accuracy of a quantity derived from processing sensor readings, we have to examine the accuracy of the sensor itself. This leads to an investigation of range camera...
Pathways to Alzheimer's disease - Hardy, J; Zetterberg, H; Bogdanovic, N; Winblad, B; Andreasen, N; Cedazo-Minguez, A; Portelius, E
Recent trials of anti-amyloid agents have not produced convincing improvements in clinical outcome in Alzheimer's disease; however, the reason for these poor or inconclusive results remains unclear. Recent genetic data continue to support the amyloid hypothesis of Alzheimer's disease with protective variants being found in the amyloid gene and both common low-risk and rare high-risk variants for disease being discovered in genes that are part of the amyloid response pathways. These data support the view that genetic variability in how the brain responds to amyloid deposition is a potential therapeutic target for the disease, and are consistent with the notion...
Magnetoencephalographic activity related to conscious perception is stable within individuals across years but not between individuals - Sandberg, K; Overgaard, M; Barnes, GR; Rees, G
Studies indicate that conscious perception is related to changes in neural activity within a time window that varies between 130 and 320 msec after stimulus presentation, yet it is not known whether such neural correlates of conscious perception are stable across time. Here, we examined the generalization across time within individuals and across different individuals. We trained classification algorithms to decode conscious perception from neural activity recorded during binocular rivalry using magnetoencephalography (MEG). The classifiers were then used to predict the perception of the same participants during different recording sessions either days or years later as well as between different...