23 research outputs found
Design of microfluidic networks
Microfluidics is a relatively new and fast growing research area in fluid mechanics. The devices in question are thin wafers containing etched or printed interconnecting channels through which fluids are pumped, which can mix and/or react at various nodes to produce an output product. Microfluidic devices have applications in many manufacturing and chemical detection processes. For example, they can be used to manufacture monodisperse droplets with very well defined properties for pharmaceutical applications; or form the basis for miniaturised ‘lab-on-a-chip’ sensor arrays for detecting biological substances or toxins
Angular momentum and clustering properties of early dark matter halos
In this paper we study the angular momentum properties of simulated dark
matter halos at high redshift that likely host the first stars in the Universe.
Calculating the spin distributions of these 10^6 - 10^7 \Msun halos in
redshift slices from , we find that they are well fit by a
log-normal distribution as is found for lower redshift and more massive halos
in earlier work. We find that both the mean value of the spin and dispersion
are largely unchanged with redshift for all halos. Our key result is that
subsamples of low and high spin 10^6 \Msun and 10^7 \Msun halos show
difference in clustering strength. In both mass bins, higher spin halos are
more strongly clustered in concordance with a tidal torquing picture for the
growth of angular momentum in dark matter halos in the CDM paradigm.Comment: 6 pages, 3 figures. Accepted MNRA
Spin and structural halo properties at high redshift in a LCDM Universe
In this paper, we examine in detail the key structural properties of high
redshift dark matter haloes as a function of their spin parameter. We perform
and analyze high resolution cosmological simulations of the formation of
structure in a LCDM Universe. We study the mass function, ellipticities,
shapes, density profiles, rotation curves and virialization for a large sample
of dark matter haloes from z = 15 - 6. We also present detailed convergence
tests for individual haloes. We find that high spin haloes have stronger
clustering strengths (up to 25%) at all mass and redshift ranges at these early
epochs. High redshift spherical haloes are also up to 50% more clustered than
aspherical haloes. High spin haloes at these redshifts are also preferentially
found in high density environments, and have more neighbors than their low spin
counterparts. We report a systematic offset in the peak of the circular
velocity curves for high and low spin haloes of the same mass. Therefore,
estimating halo masses without knowledge of the spin, using only the circular
velocity can yield errors of up to 40%. The strong dependence of key structural
properties on spin that we report here likely have important implications for
studies of star formation and feedback from these galaxies.Comment: 14 pages, 10 figures. Accepted to MNRAS
Psychosocial factors and cancer incidence (PSY-CA):Protocol for individual participant data meta-analyses
OBJECTIVES: Psychosocial factors have been hypothesized to increase the risk of cancer. This study aims (1) to test whether psychosocial factors (depression, anxiety, recent loss events, subjective social support, relationship status, general distress, and neuroticism) are associated with the incidence of any cancer (any, breast, lung, prostate, colorectal, smoking-related, and alcohol-related); (2) to test the interaction between psychosocial factors and factors related to cancer risk (smoking, alcohol use, weight, physical activity, sedentary behavior, sleep, age, sex, education, hormone replacement therapy, and menopausal status) with regard to the incidence of cancer; and (3) to test the mediating role of health behaviors (smoking, alcohol use, weight, physical activity, sedentary behavior, and sleep) in the relationship between psychosocial factors and the incidence of cancer.METHODS: The psychosocial factors and cancer incidence (PSY-CA) consortium was established involving experts in the field of (psycho-)oncology, methodology, and epidemiology. Using data collected in 18 cohorts (N = 617,355), a preplanned two-stage individual participant data (IPD) meta-analysis is proposed. Standardized analyses will be conducted on harmonized datasets for each cohort (stage 1), and meta-analyses will be performed on the risk estimates (stage 2).CONCLUSION: PSY-CA aims to elucidate the relationship between psychosocial factors and cancer risk by addressing several shortcomings of prior meta-analyses.</p
Modelling of thin-film superconductors
EThOS - Electronic Theses Online ServiceGBUnited Kingdo
Mathematical modelling of magnetically targeted drug delivery
A mathematical model for targeted drug delivery using magnetic particles is developed. This includes a diffusive flux of particles arising from interactions between erythrocytes in the microcirculation. The model is used to track particles in a vessel network. Magnetic field design is discussed and we show that it is impossible to specifically target internal regions using an externally applied fiel