Dissociable and Dynamic Components of Cognitive Control: A Developmental Electrophysiological Investigation

One standard task used to investigate the development of cognitive control is the Dimensional Change Card Sort (DCCS). Performance and patterns of brain activity associated with the DCCS show continued age-related advances into early adolescence. According to many theoretical accounts, the DCCS places demands on a single underlying executive control process. Three experiments examined the possibility that the DCCS places demands on multiple control processes that follow distinct developmental trajectories. In Experiment 1, rule switching and conflict processing made orthogonal contributions to DCCS performance. Rule switching was associated with a cue-locked late frontal negativity (LFN) event-related potential (ERP) and conflict processing was associated with stimulus-locked frontocentral N2. Moreover, rule switching and conflict processing followed distinct developmental trajectories. In Experiment 2, distributed cortical source models of the cue-locked LFN were associated with age-related differences in distributed network of regions associated with cognitive control. Source models of the stimulus-locked N2 were associated with conflict-related modulations in the anterior cingulate cortex (ACC) that varied as a function of age. In Experiment 3, dynamic modulations in conflict processing were associated with pronounced age-related behavioural and electrophysiological adaptations to prior conflict. Taken together the findings of the current set of studies suggest that multiple control processes underpin age-related advances in DCCS performance

Geographical aspects of Industrial Parks

Thesis (M.A.)--Boston UniversityOne of the most specialized methods of land use known to modern industry are Industrial Parks. In the strict sense of the term they are "tracts of land which are subdivided and developed according to a comprehensive plan for the use of a community of industries, with streets, rail lead tracks, and utilities installed before sites are sold to prospective occupants." Such Parks may vary in their size, the use to which they are put and the facilities offered. They are all, however, developed according to a plan. The first Parks were built in this country prior to the 20th century, but until 1945 only 33 Parks had been established. These were in the larger cities where labor could reach the factories by the use of public transportation or by walking. Since the end of World War II, over 125 Parks have been built and most of these have been located in the suburbs or on the fringe areas of the cities. The Parks can be an asset to the community in which they are located, whether it be a small town or a large city. Their economic influence can be of major proportion as they provide tax revenue, industrial payrolls, and job opportunities. An industry locating in a Park benefits it many ways. It is assured of pleasant surroundings and compatible neighbors as standards of selection by the owners or managers of a Park are normally high. Modern one-story buildings offered by Industrial Parks make possible the use of horizontal line production and allow the use of modern warehousing methods, thus saving time and money. In general, only two types of activity are common to Industrial Parks. There are light manufacturing and distribution. Other activities, such as research laboratories sales offices, office buildings, and retail sales outlets may be found in some of the Parks. The criteria for a successful Park is its strategic location in regard to labor, transportation and market. The Parks are located on or near major highways and almost all have rail facilities. Those lacking rail facilities are generally small sized Parks. The average size of Industrial Parks has been decreasing for the past few years, and today the average is about 440 acres with the median being 140 acres. The decrease is due in part to rising land and development costs, and to the increase in the number of Parks developed by communities. The number of Parks between 50 and 100 acres is increasing While the number of Parks over 1,000 acres is decreasing. This trend is prominent now in the New England area. Some Industrial Parks in the United States are called Garden-Type Industrial Developments. These differ from ordinary Industrial Parks in land to building ratio only. Garden-Type Parks have less than 1/2 the land built upon, while ordinary Parks build on on up to 2/3 of the land. The New England Industrial Center, in Needham, Massachusetts, is an example of a Garden-type development and is used as a case study in this paper. The New England Industrial Center is a privately developed Park. It was chosen as a case study because of the diversified character of its occupants and because it is the most completely developed Park in Greater Boston. Although it is not large by national standards, this Park offers many of the facilities common to well-developed larger Parks. It was developed in a suburb of Boston according to a plan and had all utilities in before sites were sold. The Park is located on Route 128, a major highway that runs Boston from the North to South Shore, just south of Route 9 and the Massachusetts Turnpike, the two major east-west highways. It is served by two railroads using the same set of track. The first occupant, a warehouse, moved in in 1953 and now the Park which covers 140 acres is about 90% occupied. This Park has proven a success to both the industries located in it and to the comnunity in which it located. Its suburban location leaves little to be desired. These suburban locations have become increasingly popular due both to the rising cost and to the growing scarcity of undeveloped land in the intown areas of cities. This trend will continue because of the greater abundance of peripheral land. Such a peripheral area grows in ever expanding concentric rings with highways leading to it from the central city. Industrial Parks should ideally be spread throughout this area and not concentrated along one of the highways leading from the Central City. Such overconcentration must be prevented by careful planning for the fUture. If not, the same situation of overcrowding and inefficient transportation that is now occurring in older intown industrial areas will repeat itself. Industrial Parks are not isolated entities unto themselves but an integral part of the regional fabric into which they are woven. The successful location of Industrial Parks depends upon a keen awareness of regional trends in commercial and industrial development, in shifting transportation patterns, in the character of existing, industrial real estate, and in changing land values. Careful study of the geographical aspects of Industrial Park location can contribute significantly to the vigor and stability to this newest trend in the American economy

Alcohol imagery on popularly viewed television in the UK

Background: Exposure to alcohol consumption and product imagery in films is associated with increased alcohol consumption among young people, but the extent to which exposure also occurs through television is not clear. We have measured the occurrence of alcohol imagery in prime-time broadcasting on UK free-to-air television channels. Methods: Occurrence of alcohol imagery (actual use, implied use, brand appearances or other reference to alcohol) was measured in all broadcasting on the five most popular UK television stations between 6 and 10 p.m. during 3 weeks in 2010, by 1-min interval coding. Results: Alcohol imagery occurred in over 40% of broadcasts, most commonly soap operas, feature films, sport and comedies, and was equally frequent before and after the 9 p.m. watershed. Brand appearances occurred in 21% of programmes, and over half of all sports programmes, a third of soap operas and comedies and a fifth of advertising/trailers. Three brands, Heineken, Budweiser and Carlsberg together accounted for ∼40% of all brand depictions. Conclusions: Young people are exposed to frequent alcohol imagery, including branding, in UK prime-time television. It is likely that this exposure has an important effect on alcohol consumption in young people

Metal-organic hybrid resonant terahertz absorbers with SU-8 photoresist dielectric layer

We report on the characterization of metal-organic hybrid metamaterials for MEMS-based terahertz (THz) thermal sensors and on the characterization of refractive index of SU-8 in the THz band. This type of metamaterial, coupled with the applicability of SU-8 as a structural material, offers possibilities for quick, simple microfabrication of THz imagers. SU-8, a negative photoresist, is a low-cost material that can quickly be spun onto a substrate at a wide range of thicknesses, and then photolithographically patterned into a variety of structures. It is also transparent to THz radiation and thus a suitable choice for a dielectric spacer in metamaterials. We investigated metamaterials consisting of a 0.18 μm Al ground plane and 0.18-μm layer of patterned Al separated by a dielectric spacer of ∼0.5  μm of SU-8. Absorption close to 70% at around 6.1 THz was observed. A model was developed to simulate absorption spectra of several metamaterials, agreeing well with experiments. Matching simulation to measurements was used to determine the refractive index of SU-8 at THz frequencies, extending the known values from 0.1 to 1.6 THz to as far as 10 THz. Finally, Kirchoff’s law for these metamaterials was verified and their use as THz emitters demonstrated with about 0.8  mW/cm^2 output

Numerical simulations for performance optimization of a few-cycle terawatt NOPCPA system

We present a systematic numerical design and performance study of an ultra-broadband noncollinear optical parametric chirped pulse amplification (NOPCPA) system. Using a split-step Fourier approach, we model a three-stage amplifier system which is designed for the generation of 7 fs pulses with multi-terawatt peak intensity. The numerical results are compared with recent experimental data. Several important aspects and design parameters specific to NOPCPA are identified, and the values of these parameters required to achieve optimal working conditions are investigated. We identify and analyze wavelength-dependent gain saturation effects, which are specific to NOPCPA and have a strong influence on the parametric amplification process. © Springer-Verlag 2007

Handedness as a marker of cerebral lateralization in children with and without autism

We employed a multiple case studies approach to investigate lateralization of hand actions in typically and atypically developing children between 4 and 5 years of age. We report on a detailed set of over 1200 hand actions made by four typically developing boys and four boys with autism. Participants were assessed for unimanual hand actions to both objects and the self (self-directed behaviors). Individual and group analyses suggest that typically developing children have a right hand dominance for hand actions to objects and a left hand dominance for hand actions for self-directed behaviors, revealing a possible dissociation for functional specialization of the left and right hemispheres respectively. Children with autism demonstrated mixed-handedness for both target conditions, consistent with the hypothesis that there is reduced cerebral specialization in these children. The findings are consistent with the view that observed lateralized motor action can serve as an indirect behavioral marker for evidence of cerebral lateralization

Mindfulness training with adolescents enhances metacognition and the inhibition of irrelevant stimuli : Evidence from event-related brain potentials

With the increased interest in school-based mindfulness interventions, there have been repeated calls to investigate neurodevelopmental markers of change. This non-randomised study of 16-18 year olds with wait-list control group examined possible enhancements to brain indexes of attention processing after school-based mindfulness training using event-related potentials (ERPs) (N=47 for self-report; N=40 for ERPs). Results showed significantly more negative N2 amplitudes after training, in response to irrelevant frequent stimuli and colour-deviant non-target oddball stimuli in a visual oddball paradigm. Improvements in negative thought controllability were associated with more negative N2 amplitudes post-training across groups, and mindfulness training was associated with reductions in students' hypercritical self-beliefs. There were no group differences on task performance, but regression analysis indicated that programme satisfaction explained 16% of the variance in improved target accuracy. Together these results suggest that a school-based mindfulness curriculum can enhance older adolescents' task-relevant inhibitory control of attention and perceived mental competency

Effects of school-based mindfulness training on emotion processing and well-being in adolescents : evidence from event-related potentials

In a non-randomized controlled study, we investigated the efficacy of a school-based mindfulness curriculum delivered by schoolteachers to older secondary school students (16-18 years). We measured changes in emotion processing indexed by P3b event-related potential (ERP) modulations in an affective oddball task using static human faces. ERPs were recorded to happy and sad face oddballs presented in a stimulus stream of frequent faces with neutral expression, before and after 8 weeks of mindfulness training. Whilst the mean amplitude of the P3b, an ERP component typically elicited by infrequent oddballs, decreased between testing sessions in the control group, it remained unchanged in the training group. Significant increases in self-reported well-being and fewer doctor visits for mental health support were also reported in the training group as compared to controls. The observed habituation to emotional stimuli in controls thus contrasted with maintained sensitivity in mindfulness-trained students. These results suggest that in-school mindfulness training for adolescents has scope for increasing awareness of socially relevant emotional stimuli, irrespective of valence, and thus may decrease vulnerability to depression