4,706 research outputs found
Midwest China Oral History and Archives Collection
Early life: education; receives orders from US Army for China, 1923.
China experience: organizes language school for US Army officers; gathers information for military intelligence regarding warlords prior to the Japanese war; response to the White Russians in China; impressions of missionaries, foreign business people and Chiang Kai-shek memerable American military figures in China; rescue of lost American servicemen during WWII.https://digitalcommons.luthersem.edu/china_histories/1024/thumbnail.jp
A uniformly ergodic Gibbs sampler for Bayesian survival analysis
Finite sample inference for Cox models is an important problem in many
settings, such as clinical trials. Bayesian procedures provide a means for
finite sample inference and incorporation of prior information if MCMC
algorithms and posteriors are well behaved. On the other hand, estimation
procedures should also retain inferential properties in high dimensional
settings. In addition, estimation procedures should be able to incorporate
constraints and multilevel modeling such as cure models and frailty models in a
straightforward manner. In order to tackle these modeling challenges, we
propose a uniformly ergodic Gibbs sampler for a broad class of convex set
constrained multilevel Cox models. We develop two key strategies. First, we
exploit a connection between Cox models and negative binomial processes through
the Poisson process to reduce Bayesian computation to iterative Gaussian
sampling. Next, we appeal to sufficient dimension reduction to address the
difficult computation of nonparametric baseline hazards, allowing for the
collapse of the Markov transition operator within the Gibbs sampler based on
sufficient statistics. We demonstrate our approach using open source data and
simulations
Factors for Success: Supporting Black Doctoral Students
Myriad factors impact Black doctoral student lived experiences. Black doctoral students face unique challenges in educational institutions that are not shared by their White cohorts. This literature review surveys current scholarship about these challenges and the educational experiences that emerge from them. Using an intersectional framework, the authors review the extant literature from the perspective of four primary themes: socialization, mentoring, financial wellness, and belonging. The authors contend that improving practices related to each of these areas can result in improved experiences and outcomes for Black doctoral students as they matriculate through graduate programs
A Viscous Heating Mechanism for the Hot Plasma in the Galactic Center Region
In addition to lines originating in a soft phase at ~0.8 keV and to cold
molecular clouds, the X-ray spectra from the Galactic center region also
exhibit properties similar to those of a diffuse, thin, very hot plasma at 8
keV on a scale of hundreds of parsecs. This phase is surprising for more than
one reason. First, such a hot plasma should not be bound to the Galactic plane
and the power needed to sustain the escaping matter would be higher then any
known source. Second, there is no known mechanism able to heat the plasma to
more than a few keV. Recently we have suggested that, hydrogen having escaped,
the hot plasma could be a helium plasma, heavy enough to be gravitationally
confined. In this case, the required power is much more reasonable. We present
here a possible heating mechanism which taps the gravitational energy of the
molecular clouds. We note that the 8 keV plasma is highly viscous and we show
how viscous friction of molecular clouds flowing within the hot phase can
dissipate energy in the gas and heat it. We detail the MHD wake of a spherical
cloud by considering the different MHD waves the cloud can excite. We find that
most of the energy is dissipated by the damping of Alfvenic perturbations in
two possible manners, namely by non-linear effects and by a large scale
curvature of the field lines. Depending on the field strength, this heating can
balance the radiative cooling. We note that the plasma parameters may be
optimal to make the dissipation most efficient, suggesting a self-regulation
mechanism. The loss of kinetic and gravitational energy also causes accretion
of the clouds and may have significant action on the gas dynamics in this
region between the large scale, bar dominated flow and the central accretion to
the massive black hole.Comment: 17 pages, 6 figures, accepted for publication in A&
Agricultural Turns, Geographical Turns: Retrospect and Prospect.
It is accepted that British rural geography has actively engaged with the ‘cultural turn’, leading to a resurgence of research within the sub-discipline. However, a reading of recent reviews suggests that the cultural turn has largely, if not completely, bypassed those geographers interested in the agricultural sector. Farming centred engagements with notions of culture have been relatively limited compared with those concerned with the non-agricultural aspects of rural space. Indeed, agricultural geography represents something of an awkward case in the context of the disciplinary turn to culture, a situation that demands further exposition. In seeking explanation, it becomes evident that research on the farm sector is more culturally informed than initially appears. This paper argues that there have been both interesting and important engagements between agricultural geography and cultural perspectives over the past decade. The paper elaborates four specific areas of research which provide evidence for concern about the ‘culture’ within agriculture. The future contribution that culturally informed perspectives in geographical research can bring to agricultural issues is outlined by way of conclusion
Testing causality violation on spacetimes with closed timelike curves
Generalized quantum mechanics is used to examine a simple two-particle
scattering experiment in which there is a bounded region of closed timelike
curves (CTCs) in the experiment's future. The transitional probability is shown
to depend on the existence and distribution of the CTCs. The effect is
therefore acausal, since the CTCs are in the experiment's causal future. The
effect is due to the non-unitary evolution of the pre- and post-scattering
particles as they pass through the region of CTCs. We use the time-machine
spacetime developed by Politzer [1], in which CTCs are formed due to the
identification of a single spatial region at one time with the same region at
another time. For certain initial data, the total cross-section of a scattering
experiment is shown to deviate from the standard value (the value predicted if
no CTCs existed). It is shown that if the time machines are small, sparsely
distributed, or far away, then the deviation in the total cross-section may be
negligible as compared to the experimental error of even the most accurate
measurements of cross-sections. For a spacetime with CTCs at all points, or one
where microscopic time machines pervade the spacetime in the final moments
before the big crunch, the total cross-section is shown to agree with the
standard result (no CTCs) due to a cancellation effect.Comment: 28 pages, 8 figures, late
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The calculation, thresholds and reporting of inter-limb strength asymmetry: a systematic review
The prevalence of inter-limb strength differences is well documented in the literature however, there are inconsistencies related to measurement and reporting, and the normative values and effects associated with inter-limb asymmetry. Therefore, the aims of this systematic review were to: 1) assess the appropriateness of existing indices for the calculation of asymmetry, 2) interrogate the evidence basis for literature reported thresholds used to define asymmetry and 3) summarise normative levels of inter-limb strength asymmetry and their effects on injury and performance. To conduct this systematic review, scientific databases (PubMed, Scopus, SPORTDiscus and Web of Science) were searched and a total of 3,594 articles were retrieved and assessed for eligibility and article quality. The robustness of each identified asymmetry index was assessed, and the evidence-basis of the identified asymmetry thresholds was appraised retrospectively using the references provided. Fifty-three articles were included in this review. Only four of the twelve identified indices were unaffected by the limitations associated with selecting a reference limb. Eighteen articles applied a threshold to original research to identify “abnormal” asymmetry, fifteen of which utilised a threshold between 10-15%, yet this threshold was not always supported by appropriate evidence. Asymmetry scores ranged between and within populations from approximate symmetry to asymmetries larger than 15%. When reporting the effects of strength asymmetries, increased injury risk and detriments to performance were often associated with larger asymmetry, however the evidence was inconsistent. Limitations of asymmetry indices should be recognised, particularly those that require selection of a reference limb. Failure to reference the origin of the evidence for an asymmetry threshold reinforces doubt over the use of arbitrary thresholds, such as 10-15%. Therefore, an individual approach to defining asymmetry may be necessary to refine robust calculation methods and to establish appropriate thresholds across various samples and methodologies that enable appropriate conclusions to be drawn
Tisa: A Language Design and Modular Verification Technique for Temporal Policies in Web Services
Web services are distributed software components, that are decoupled from each other using interfaces with specified functional behaviors. However, such behavioral specifications are insufficient to demonstrate compliance with certain temporal non-functional policies. An example is demonstrating that a patient’s health-related query sent to a health care service is answered only by a doctor (and not by a secretary). Demonstrating compliance with such policies is important for satisfying governmental privacy regulations. It is often necessary to expose the internals of the web service implementation for demonstrating such compliance, which may compromise modularity. In this work, we provide a language design that enables such demonstrations, while hiding majority of the service’s source code. The key idea is to use greybox specifications to allow service providers to selectively hide and expose parts of their implementation. The overall problem of showing compliance is then reduced to two subproblems: whether the desired properties are satisfied by the service’s greybox specification, and whether this greybox specification is satisfied by the service’s implementation. We specify policies using LTL and solve the first problem by model checking. We solve the second problem by refinement techniques
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Peripheral inflammation in prodromal Alzheimer's and Lewy body dementias.
OBJECTIVES: There is growing evidence for the role of systemic inflammation in Alzheimer's disease (AD) and other neurodegenerative diseases; however the systemic inflammatory profile in dementia with Lewy bodies (DLB) has never before been investigated. This study aimed to characterise systemic inflammatory mediators in established DLB and AD, as well as in their prodromal, mild cognitive impairment (MCI) phases. METHODS: We obtained plasma samples from patients with DLB (n=37), AD (n=20), MCI with DLB profile (n=38), MCI with AD profile (n=20) and healthy control subjects (n=20). The following inflammatory biomarkers were measured using Roche cobas c702 and Meso Scale Discovery V-Plex Plus: high-sensitivity C-reactive protein, interferon-gamma, interleukin (IL)-10, IL-12p70, IL-13, IL-1beta, IL-2, IL-4, IL-6, IL-8 and tumour necrosis factor-alpha. RESULTS: We found significantly higher levels of IL-10, IL-1beta, IL-4 and IL-2 in both MCI groups (P<0.001), while there was no significant difference in inflammatory markers between dementia groups and controls. Furthermore, increased disease severity was associated with lower levels of IL-1beta, IL-2 and IL-4 (P<0.05). INTERPRETATION: We have shown for the first time that in both DLB and AD, increased peripheral inflammation occurs early at the MCI disease stages. These data support a role for inflammation early in the disease process, and have important implications for the stage of disease where trials of anti-inflammatory medication should be focused.We would like to acknowledge our funders; the National Institute for Health Research (NIHR) Newcastle Biomedical Research Unit in Lewy Body Dementia based at Newcastle upon Tyne NHS Foundation Trust and Newcastle University. Thanks to The Dementias and Neurodegenerative Diseases Research Network (DeNDRoN). The views expressed are those of the authors and not necessarily those of the NHS, the NIHR or the Department of Health.
Eleanor King is also grateful to the Royal College of Psychiatrists Pathfinder Fellowship for the grant that was provided for this project.
We would also like to thank Melanie Maitland and friends for their donations to our research in Lewy Body Dementi
A Study of the -component of the wave-function in light nuclei
We have measured cross sections for the reactions on
, , and in quasi-free
kinematics at incident pion beam energy 500 MeV. An enhancement of the
cross section in this kinematics is observed. If this is
interpreted as due to quasi-free scattering from pre-existing
components of the nuclear wave function, the extracted probabilities are in
agreement with theoretical expectations.Comment: 3 pages, 3 figures, 1 tabl
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