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Integrating high speed rail systems into urban environments : a comprehensive evaluation
Construction of a high speed rail system comes with an exhaustive list of challenges. Integrating the system into an existing urban environment is a particularly difficult proposition, given the dense developments and infrastructure systems already in place. Locating a station within a city is a delicate balance between a multitude of factors that include cost, station accessibility, required infrastructure and intermodal connectivity. Acquiring the rail alignment requires even more diplomacy. This thesis explores existing urban integration of current high speed rail systems and stations, evaluating prevalent high speed systems around the world to gauge best practices. Several European countries are notable for their direct connections into city center stations and urban transportation systems, providing passengers with quick, direct access to their final destinations. China and Taiwan have adopted a different approach with many cities, locating stations at the urban fringe and providing a base for transit-oriented development. After a review of existing systems around the world and high speed rail proposals in the United States and specifically, Texas, case studies are performed on the cities of Dallas and Houston. Using current and prior proposals by the Texas TGV and Texas Central Railroad, potential station sites in the two Texas cities will be analyzed for their potential for development and connectivity to transit and roadway systems. The selection of an optimal station location will be aided using criteria from the Federal Railroad Administration and from interviews with planning professionals familiar with both metropolitan areas. In Dallas, the South Side site immediately south of the existing Union Station is recommended for future development while in Houston, a station connecting into the Northwest Transit Center is preferred.Civil, Architectural, and Environmental Engineerin
The Australian Imaging, Biomarkers and Lifestyle (AIBL) Study of Aging: Methodology and Baseline Characteristics of 1112 Individuals Recruited for a Longitudinal Study of Alzheimer\u27s Disease
Background: The Australian Imaging, Biomarkers and Lifestyle (AIBL) flagship study of aging aimed to recruit 1000 individuals aged over 60 to assist with prospective research into Alzheimer\u27s disease (AD). This paper describes the recruitment of the cohort and gives information about the study methodology, baseline demography, diagnoses, medical comorbidities, medication use, and cognitive function of the participants. Methods: Volunteers underwent a screening interview, had comprehensive cognitive testing, gave 80 ml of blood, and completed health and lifestyle questionnaires. One quarter of the sample also underwent amyloid PET brain imaging with Pittsburgh compound B (PiB PET) and MRI brain imaging, and a subgroup of 10% had ActiGraph activity monitoring and body composition scanning. Results: A total of 1166 volunteers were recruited, 54 of whom were excluded from further study due to comorbid disorders which could affect cognition or because of withdrawal of consent. Participants with AD (211) had neuropsychological profiles which were consistent with AD, and were more impaired than participants with mild cognitive impairment (133) or healthy controls (768), who performed within expected norms for age on neuropsychological testing. PiB PET scans were performed on 287 participants, 100 had DEXA scans and 91 participated in ActiGraph monitoring. Conclusion: The participants comprising the AIBL cohort represent a group of highly motivated and well-characterized individuals who represent a unique resource for the study of AD. They will be reassessed at 18-month intervals in order to determine the predictive utility of various biomarkers, cognitive parameters and lifestyle factors as indicators of AD, and as predictors of future cognitive decline
Longitudinal trajectories in cortical thickness and volume atrophy: Superior cognitive performance does not protect against brain atrophy in older adults
Background:
Previous research has identified a small subgroup of older adults that maintain a high level of cognitive functioning well into advanced age. Investigation of those with superior cognitive performance (SCP) for their age is important, as age-related decline has previously been thought to be inevitable.
Objective:
Preservation of cortical thickness and volume was evaluated in 76 older adults with SCP and 100 typical older adults (TOAs) assessed up to five times over six years.
Methods:
Regions of interest (ROIs) found to have been associated with super-aging status (a construct similar to SCP status) in previous literature were investigated, followed by a discovery phase analyses of additional regions. SCPs were aged 70 + at baseline, scoring at/above normative memory (CVLT-II) levels for demographically similar individuals aged 30–44 years old, and in the unimpaired range for all other cognitive domains over the course of the study.
Results:
In linear mixed models, following adjustment for multiple comparisons, there were no significant differences between rates of thinning or volume atrophy between SCPs and TOAs in previously identified ROIs, or the discovery phase analyses. With only amyloid-β negative individuals in the analyses, again there were no significant differences between SCPs and TOAs.
Conclusion:
The increased methodological rigor in classifying groups, together with the influence of cognitive reserve, are discussed as potential factors accounting for our findings as compared to the extant literature on those with superior cognitive performance for their age
Caloric restriction augments radiation efficacy in breast cancer.
Dietary modification such as caloric restriction (CR) has been shown to decrease tumor initiation and progression. We sought to determine if nutrient restriction could be used as a novel therapeutic intervention to enhance cytotoxic therapies such as radiation (IR) and alter the molecular profile of triple-negative breast cancer (TNBC), which displays a poor prognosis. In two murine models of TNBC, significant tumor regression is noted with IR or diet modification, and a greater regression is observed combining diet modification with IR. Two methods of diet modification were compared, and it was found that a daily 30% reduction in total calories provided more significant tumor regression than alternate day feeding. At the molecular level, tumors treated with CR and IR showed less proliferation and more apoptosis. cDNA array analysis demonstrated the IGF-1R pathway plays a key role in achieving this physiologic response, and multiple members of the IGF-1R pathway including IGF-1R, IRS, PIK3ca and mTOR were found to be downregulated. The innovative use of CR as a novel therapeutic option has the potential to change the biology of tumors and enhance the opportunity for clinical benefit in the treatment of patients with TNBC
Parametric modelling of the 3.6um to 8um colour distributions of galaxies in the SWIRE Survey
We fit a parametric model comprising a mixture of multi-dimensional Gaussian
functions to the 3.6 to 8um colour and optical photo-z distribution of galaxy
populations in the ELAIS-N1 and Lockman Fields of SWIRE. For 16,698 sources in
ELAIS-N1 we find our data are best modelled (in the sense of the Bayesian
Information Criterion) by the sum of four Gaussian distributions or modes (C_a,
C_b, C_c and C_d). We compare the fit of our empirical model with predictions
from existing semi-analytic and phenomological models. We infer that our
empirical model provides a better description of the mid-infrared colour
distribution of the SWIRE survey than these existing models. This colour
distribution test is thus a powerful model discriminator and complementary to
comparisons of number counts. We use our model to provide a galaxy
classification scheme and explore the nature of the galaxies in the different
modes of the model. C_a consists of dusty star-forming systems such as ULIRG's.
Low redshift late-type spirals are found in C_b, where PAH emission dominates
at 8um. C_c consists of dusty starburst systems at intermediate redshifts. Low
redshift early-type spirals and ellipticals dominate C_d. We thus find a
greater variety of galaxy types than one can with optical photometry alone.
Finally we develop a new technique to identify unusual objects, and find a
selection of outliers with very red IRAC colours. These objects are not
detected in the optical, but have very strong detections in the mid-infrared.
These sources are modelled as dust-enshrouded, strongly obscured AGN, where the
high mid-infrared emission may either be attributed to dust heated by the AGN
or substantial star-formation. These sources have z_ph ~ 2-4, making them
incredibly infrared luminous, with a L_IR ~ 10^(12.6-14.1) L_sun.Comment: 44 pages, 10 figures, 6 tables. Accepted for publication in the
Astronomical Journa
Improving mental health and psychosocial wellbeing in humanitarian settings: Reflections on research funded through R2HC
From Springer Nature via Jisc Publications RouterMajor knowledge gaps remain concerning the most effective ways to address mental health and psychosocial needs of populations affected by humanitarian crises. The Research for Health in Humanitarian Crisis (R2HC) program aims to strengthen humanitarian health practice and policy through research. As a significant portion of R2HC’s research has focused on mental health and psychosocial support interventions, the program has been interested in strengthening a community of practice in this field. Following a meeting between grantees, we set out to provide an overview of the R2HC portfolio, and draw lessons learned. In this paper, we discuss the mental health and psychosocial support-focused research projects funded by R2HC; review the implications of initial findings from this research portfolio; and highlight four remaining knowledge gaps in this field. Between 2014 and 2019, R2HC funded 18 academic-practitioner partnerships focused on mental health and psychosocial support, comprising 38% of the overall portfolio (18 of 48 projects) at a value of approximately 7.2 million GBP. All projects have focused on evaluating the impact of interventions. In line with consensus-based recommendations to consider a wide range of mental health and psychosocial needs in humanitarian settings, research projects have evaluated diverse interventions. Findings so far have both challenged and confirmed widely-held assumptions about the effectiveness of mental health and psychosocial interventions in humanitarian settings. They point to the importance of building effective, sustained, and diverse partnerships between scholars, humanitarian practitioners, and funders, to ensure long-term program improvements and appropriate evidence-informed decision making. Further research needs to fill knowledge gaps regarding how to: scale-up interventions that have been found to be effective (e.g., questions related to integration across sectors, adaptation of interventions across different contexts, and optimal care systems); address neglected mental health conditions and populations (e.g., elderly, people with disabilities, sexual minorities, people with severe, pre-existing mental disorders); build on available local resources and supports (e.g., how to build on traditional, religious healing and community-wide social support practices); and ensure equity, quality, fidelity, and sustainability for interventions in real-world contexts (e.g., answering questions about how interventions from controlled studies can be transferred to more representative humanitarian contexts).All studies described here were funded by Elrha’s Research for Health in Humanitarian Crises (R2HC) Programme, which aims to improve health outcomes by strengthening the evidence base for public health interventions in humanitarian crises.14pubpu
The Cosmic Origins Spectrograph
The Cosmic Origins Spectrograph (COS) is a moderate-resolution spectrograph with unprecedented sensitivity that was installed into the Hubble Space Telescope (HST) in May 2009, during HST Servicing Mission 4 (STS-125). We present the design philosophy and summarize the key characteristics of the instrument that will be of interest to potential observers. For faint targets, with flux F(sub lambda) approximates 1.0 X 10(exp -14) ergs/s/cm2/Angstrom, COS can achieve comparable signal to noise (when compared to STIS echelle modes) in 1-2% of the observing time. This has led to a significant increase in the total data volume and data quality available to the community. For example, in the first 20 months of science operation (September 2009 - June 2011) the cumulative redshift pathlength of extragalactic sight lines sampled by COS is 9 times that sampled at moderate resolution in 19 previous years of Hubble observations. COS programs have observed 214 distinct lines of sight suitable for study of the intergalactic medium as of June 2011. COS has measured, for the first time with high reliability, broad Lya absorbers and Ne VIII in the intergalactic medium, and observed the HeII reionization epoch along multiple sightlines. COS has detected the first CO emission and absorption in the UV spectra of low-mass circumstellar disks at the epoch of giant planet formation, and detected multiple ionization states of metals in extra-solar planetary atmospheres. In the coming years, COS will continue its census of intergalactic gas, probe galactic and cosmic structure, and explore physics in our solar system and Galaxy
The Cosmic Origins Spectrograph
The Cosmic Origins Spectrograph (COS) is a moderate-resolution spectrograph
with unprecedented sensitivity that was installed into the Hubble Space
Telescope (HST) in May 2009, during HST Servicing Mission 4 (STS-125). We
present the design philosophy and summarize the key characteristics of the
instrument that will be of interest to potential observers. For faint targets,
with flux F_lambda ~ 1.0E10-14 ergs/s/cm2/Angstrom, COS can achieve comparable
signal to noise (when compared to STIS echelle modes) in 1-2% of the observing
time. This has led to a significant increase in the total data volume and data
quality available to the community. For example, in the first 20 months of
science operation (September 2009 - June 2011) the cumulative redshift
pathlength of extragalactic sight lines sampled by COS is 9 times that sampled
at moderate resolution in 19 previous years of Hubble observations. COS
programs have observed 214 distinct lines of sight suitable for study of the
intergalactic medium as of June 2011. COS has measured, for the first time with
high reliability, broad Lya absorbers and Ne VIII in the intergalactic medium,
and observed the HeII reionization epoch along multiple sightlines. COS has
detected the first CO emission and absorption in the UV spectra of low-mass
circumstellar disks at the epoch of giant planet formation, and detected
multiple ionization states of metals in extra-solar planetary atmospheres. In
the coming years, COS will continue its census of intergalactic gas, probe
galactic and cosmic structure, and explore physics in our solar system and
Galaxy.Comment: 17 pages, 15 figure
Hard Cases of Comparison
In hard cases of comparison, people are faced with two options neither of which is conceived of as better, worse, or equally good compared to the other. Most philosophers claim that hard cases (1) can indeed be distinguished from cases in which two options are equally good, and (2) can be characterized by a failure of transitive reasoning. It is a much more controversial matter and at the heart of an ongoing debate, whether the options in hard cases of comparison should be interpreted as incomparable, on par, or roughly equal. So far, however, none of these claims and interpretations have been tested. This paper presents the first empirical investigation on hard cases, intransitive reasoning, and incomparability. Our results reveal that hard cases present real-world dilemmas in which a significant majority of people violate transitivity. After suggesting a way of operationalizing the notion of incomparability, we provide empirical evidence that the options in some hard cases are not considered to be incomparable. Theories of rough equality or parity seem to provide better interpretations of our results
Be prepared: communism and the politics of scouting in 1950s Britain
This article examines the exposure, and in some cases dismissal, of Boy Scouts who belonged or sympathised with the Young Communist League in Britain during the early 1950s. A focus on the rationale and repercussions of the organisation's approach and attitudes towards ‘Red Scouts’ found within their ‘ranks’ extends our understanding of youth movements and their often complex and conflicting ideological foundations. In particular, the post-World War Two period presented significant challenges to these spaces of youth work in terms of broader social and political change in Britain. An analysis of the politics of scouting in relation to Red Scouts questions not only the assertion that British McCarthyism was ‘silent’, but also brings young people firmly into focus as part of a more everyday politics of communism in British society
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