Differentiating core and co-opted mechanisms in calculation: The neuroimaging of calculation in aphasia

The role of language in exact calculation is the subject of debate. Some behavioral and functional neuroimaging investigations of healthy participants suggest that calculation requires language resources. However, there are also reports of individuals with severe aphasic language impairment who retain calculation ability. One possibility in resolving these discordant findings is that the neural basis of calculation has undergone significant reorganization in aphasic calculators. Using fMRI, we examined brain activations associated with exact addition and subtraction in two patients with severe agrammatic aphasia and retained calculation ability. Behavior and brain activations during two-digit addition and subtraction were compared to those of a group of 11 healthy, age-matched controls. Behavioral results confirmed that both patients retained calculation ability. Imaging findings revealed individual differences in processing, but also a similar activation pattern across patients and controls in bilateral parietal cortices. Patients differed from controls in small areas of increased activation in peri-lesional regions, a shift from left fronto-temporal activation to the contralateral region, and increased activations in bilateral superior parietal regions. Our results suggest that bilateral parietal cortex represents the core of the calculation network and, while healthy controls may recruit language resources to support calculation, these mechanisms are not mandatory in adult cognition.

Child anxiety and parenting in England and Italy: the moderating role of maternal warmth

BACKGROUND: Parenting factors have been implicated in the aetiology and maintenance of child anxiety. Most research has been correlational with little experimental or longitudinal work. Cross-cultural comparison could be illuminating. A comparison of Italian and British children and their mothers was conducted. METHODS: A sample of 8- to 10-year old children, 60 Italian and 49 English, completed the Spence Child Anxiety Scale. Mothers also completed two questionnaires of parenting: the Skills of Daily Living Checklist (assessing maternal autonomy granting) and the Parent-Child Interaction Questionnaire (assessing maternal intrusiveness). Parenting was assessed in two video-recorded blindly rated mother-child interaction tasks, the 'belt-buckling tasks and the 'etch-a-sketch', providing objective indices of overcontrol, warmth, lack of autonomy granting, and overprotection. RESULTS: There were no differences between the children in overall anxiety and specific forms of anxiety. Parenting, however, was markedly different for the two countries. Compared to English mothers, on the two questionnaires, Italian mothers were significantly less autonomy granting and more intrusive; and in terms of the observed indices, a significantly greater proportion of the Italian mothers displayed a high level of both overprotection and overcontrol, and a low level of autonomy granting. Notably, Italian mothers evidenced significantly more warmth than English mothers; and maternal warmth was found to moderate the impact of self-reported maternal intrusiveness on the level of both overall child anxiety and the level of child separation anxiety; and it also moderated the relationship between both observed maternal intrusiveness and overall child anxiety and observed maternal overprotectiveness and child separation anxiety. CONCLUSIONS: Although, compared to the British mothers, the Italian mothers were more likely to evidence high levels of parenting behaviours previously found to be anxiogenic, the high levels of warmth displayed by these mothers to their children appears to have neutralised the adverse impact of these behaviours.

Bank integration and co-movements across housing markets

This paper investigates whether bank integration measured by cross-border bank flows can capture the co-movements across housing markets in developed countries by using a spatial dynamic panel model. The transmission can occur through a global banking channel in which global banks intermediate wholesale funding to local banks. Changes in financial conditions are passed across borders through the banks’ balance-sheet exposure to credit, currency, maturity, and funding risks resulting in house price spillovers. While controlling for country-level and global factors, we find significant co-movement across housing markets of countries with proportionally high bank integration. Bank integration can better capture house price co-movements than other measures of economic integration. Once we account for bank exposure, other spatial linkages traditionally used to account for return co-movements across region – such as trade, foreign direct investment, portfolio investment, geographic proximity, etc. – become insignificant. Moreover, we find that the co-movement across housing markets decreases for countries with less developed mortgage markets characterized by fixed mortgage rate contracts, low limits of loan-to-value ratios and no mortgage equity withdrawal.

Variability and trends in England and Wales precipitation

The England and Wales precipitation (EWP) dataset is a homogeneous time series of daily accumulations from 1931 to 2014, composed from rain gauge observations spanning the region. The daily regional-average precipitation statistics are shown to be well described by a Weibull distribution, which is used to define extremes in terms of percentiles. Computed trends in annual and seasonal precipitation are sensitive to the period chosen, due to large variability on interannual and decadal timescales. Atmospheric circulation patterns associated with seasonal precipitation variability are identified. These patterns project onto known leading modes of variability, all of which involve displacements of the jet stream and storm-track over the eastern Atlantic. The intensity of daily precipitation for each calendar season is investigated by partitioning all observations into eight intensity categories contributing equally to the total precipitation in the dataset. Contrary to previous results based on shorter periods, no significant trends of the most intense categories are found between 1931 and 2014. The regional-average precipitation is found to share statistical properties common to the majority of individual stations across England and Wales used in previous studies. Statistics of the EWP data are examined for multi-day accumulations up to 10 days, which are more relevant for river flooding. Four recent years (2000, 2007, 2008 and 2012) have a greater number of extreme events in the 3-and 5-day accumulations than any previous year in the record. It is the duration of precipitation events in these years that is remarkable, rather than the magnitude of the daily accumulations.

Modelling the medieval economy: money, prices and income in England, 1263-1520

This chapter presents a simple econometric model of the medieval English economy, focusing on the relationship between money, prices and incomes. The model is estimated using annual data for the period 1263-1520 obtained from various sources. The start date is determined by the availability of continuous runs of annual data, while the finishing date immediately precedes the take-off of Tudor price inflation. Accounts from the ecclesiastical and monastic estates have survived in great numbers for this period, thereby ensuring that crop yields can be estimated from a regionally representative set of estates.

Geographical concentration in the institutional market for office property in England and Wales

This paper examines the regional investment practices of institutional investors in the commercial real estate office market in 1998 and 2003 in England and Wales. Consistent with previous studies in the US the findings show that investors concentrate their holdings in a few (urban) areas and that this concentration has become more pronounced as investors have rationalised their portfolio holdings. The findings also indicate that office investment does not fully correlate with the UK urban hierarchy, as measured by population, but is focused on urban areas with high service sector employment. Finally, the pre-eminence of the City of London and and West End office markets as the key focus of institutional investment is confirmed.

Think local, act local? Issues of co-ordination and integration in Local Agenda 21

The political response to the complex package of environmental problems which threaten the future of our planet has been to introduce a new agenda of environmental action based on the principles of sustainability and subsidiarity. This has been crystallised in world agreements signed at the Earth Summit in Rio. One of these, Agenda 21, calls for the governments and communities of the world to prepare action plans for their areas which can build consensus between the various stakeholder groups and feed the principles of sustainable development back into their policies and day-to-day practices. This paper explores the experience of Local Agenda 21 type processes at three levels in the South East of England: the regional, county (sub-regional) and local level. In particular it undertakes a critical appraisal of the success of these participatory and consensus-building exercises in developing an integrated and co-ordinated approach to environmental action planning. It concludes that, although much useful work has been done in raising awareness and modifying policy and practice, there are significant cultural and institutional barriers which are hindering progress.

Structure of the planetary boundary layer over southeast England: modeling and measurements

The Weather Research and Forecasting model was applied to analyze variations in the planetary boundary layer (PBL) structure over Southeast England including central and suburban London. The parameterizations and predictive skills of two nonlocal mixing PBL schemes, YSU and ACM2, and two local mixing PBL schemes, MYJ and MYNN2, were evaluated over a variety of stability conditions, with model predictions at a 3 km grid spacing. The PBL height predictions, which are critical for scaling turbulence and diffusion in meteorological and air quality models, show significant intra-scheme variance (> 20%), and the reasons are presented. ACM2 diagnoses the PBL height thermodynamically using the bulk Richardson number method, which leads to a good agreement with the lidar data for both unstable and stable conditions. The modeled vertical profiles in the PBL, such as wind speed, turbulent kinetic energy (TKE), and heat flux, exhibit large spreads across the PBL schemes. The TKE predicted by MYJ were found to be too small and show much less diurnal variation as compared with observations over London. MYNN2 produces better TKE predictions at low levels than MYJ, but its turbulent length scale increases with height in the upper part of the strongly convective PBL, where it should decrease. The local PBL schemes considerably underestimate the entrainment heat fluxes for convective cases. The nonlocal PBL schemes exhibit stronger mixing in the mean wind fields under convective conditions than the local PBL schemes and agree better with large-eddy simulation (LES) studies.