Mobile impurities in integrable models

We use a mobile impurity or depleton model to study elementary excitations in one-dimensional integrable systems. For Lieb-Liniger and bosonic Yang-Gaudin models we express two phenomenological parameters characterising renormalised inter- actions of mobile impurities with superfluid background: the number of depleted particles, $N$ and the superfluid phase drop $\pi J$ in terms of the corresponding Bethe Ansatz solution and demonstrate, in the leading order, the absence of two-phonon scattering resulting in vanishing rates of inelastic processes such as viscosity experienced by the mobile impuritiesComment: 25 pages, minor corrections made to the manuscrip

Phonon lasing from optical frequency comb illumination of a trapped ion

An atomic transition can be addressed by a single tooth of an optical frequency comb if the excited state lifetime ($\tau$) is significantly longer than the pulse repetition period ($T_\mathrm{r}$). In the crossover regime between fully-resolved and unresolved comb teeth ($\tau \lessapprox T_\mathrm{r}$), we observe Doppler cooling of a pre-cooled trapped atomic ion by a single tooth of a frequency-doubled optical frequency comb. We find that for initially hot ions, a multi-tooth effect gives rise to lasing of the ion's harmonic motion in the trap, verified by acoustic injection locking. The gain saturation of this phonon laser action leads to a comb of steady-state oscillation amplitudes, allowing hot ions to be loaded directly into the trap and laser cooled to crystallization despite the presence of hundreds of blue-detuned teeth.Comment: 5 pages, 4 figure

Enhancement of methyl-aminolevulinate photodynamic therapy by iron chelation with CP94: an in vitro investigation and clinical dose-escalating safety study for the treatment of nodular basal cell carcinoma.

Clinical TrialAuthor version of article. The final publication is available at Springer via: http://dx.doi.org/10.1007/s00432-008-0358-6PURPOSE: Methyl-aminolevulinate (MAL) photodynamic therapy (PDT) is a cancer therapy that combines the selective accumulation of a photosensitizer in tumor tissue with visible light (and tissue oxygen) to produce reactive oxygen species. This results in cellular damage and ablation of tumor tissue. Combining iron chelators with MAL has the potential to increase the accumulation of the photosensitizer protoporphyrin IX (PpIX) by reducing its bioconversion to heme. This paper investigates this method of enhancement both in vitro and for the first time clinically for the treatment of nodular basal cell carcinoma (BCC). METHODS: Enhancement of MAL-induced PpIX accumulation by the iron chelator CP94 was quantified fluorometrically in human cultured cells (including three dermatological cell types). An open, dose-escalating, pilot study was then conducted in patients with nodular BCC, to determine the safety of this pharmacological modification. RESULTS: Large enhancements in PpIX accumulation were observed in the cultured cells when co-incubated with the iron chelator CP94. Clinically the addition of CP94 was found to be feasible and safe. In addition greater reductions in tumor depth were observed in the CP94 co-incubated tumors. CONCLUSION: Iron chelation by CP94 is an effective enhancer of MAL-induced PpIX accumulation in vitro. This method of enhancement was safely applied to a clinical PDT protocol with no unexpected adverse effects reported. Although the clinical investigation was only intended to be a small pilot to assess safety, enhancements in tumor clearance were observed both clinically and histologically when CP94 was included in the photosensitizing cream.Duchy Health Charity Limite

Reducing risks with a serum-free medium for MRC-5 based vaccine production

The World Health Organization has set limits to the amount of bovine serum albumin (BSA) in vaccines to 50ng/dose. Vaccines that are produced with MRC-5 or other diploid cells are cultured in classical medium with bovine serum. Fetal bovine serum contains on average 23g/L BSA which adds a burden to downstream vaccine formulation. To reduce risks associated with bovine sera, we have developed an animal origin-free vaccine production medium for diploid cells. The medium is paired with a serum-free growth medium that supports direct recovery from thaw and adaptation-free expansion, while resulting in performance that is comparable to serum-containing medium. We confirmed virus production with varicella zoster virus and vesicular stomatitis virus (as an analog to rabies virus) and demonstrated titers that were up to one log higher than classical medium control cultures. Taken together, we have developed a workflow for diploid cells consisting of a serum-free medium for growth and an animal origin-free medium for virus production. By switching to a serum-free process, vaccine manufacturers can reduce dependency on serum, production and purification costs, and increase product consistency and safety

How to Optimally Constrain Galaxy Assembly Bias: Supplement Projected Correlation Functions with Count-in-cells Statistics

Most models for the connection between galaxies and their haloes ignore the possibility that galaxy properties may be correlated with halo properties other than mass, a phenomenon known as galaxy assembly bias. Yet, it is known that such correlations can lead to systematic errors in the interpretation of survey data. At present, the degree to which galaxy assembly bias may be present in the real Universe, and the best strategies for constraining it remain uncertain. We study the ability of several observables to constrain galaxy assembly bias from redshift survey data using the decorated halo occupation distribution (dHOD), an empirical model of the galaxy--halo connection that incorporates assembly bias. We cover an expansive set of observables, including the projected two-point correlation function $w_{\mathrm{p}}(r_{\mathrm{p}})$, the galaxy--galaxy lensing signal $\Delta \Sigma(r_{\mathrm{p}})$, the void probability function $\mathrm{VPF}(r)$, the distributions of counts-in-cylinders $P(N_{\mathrm{CIC}})$, and counts-in-annuli $P(N_{\mathrm{CIA}})$, and the distribution of the ratio of counts in cylinders of different sizes $P(N_2/N_5)$. We find that despite the frequent use of the combination $w_{\mathrm{p}}(r_{\mathrm{p}})+\Delta \Sigma(r_{\mathrm{p}})$ in interpreting galaxy data, the count statistics, $P(N_{\mathrm{CIC}})$ and $P(N_{\mathrm{CIA}})$, are generally more efficient in constraining galaxy assembly bias when combined with $w_{\mathrm{p}}(r_{\mathrm{p}})$. Constraints based upon $w_{\mathrm{p}}(r_{\mathrm{p}})$ and $\Delta \Sigma(r_{\mathrm{p}})$ share common degeneracy directions in the parameter space, while combinations of $w_{\mathrm{p}}(r_{\mathrm{p}})$ with the count statistics are more complementary. Therefore, we strongly suggest that count statistics should be used to complement the canonical observables in future studies of the galaxy--halo connection.Comment: Figures 3 and 4 show the main results. Published in Monthly Notices of the Royal Astronomical Societ

Optimizing scale-up of Vero cells cultured on microcarriers in serum-free medium for vaccine production

Vaccine production with adherent cell lines faces multiple challenges which include selection of a suitable vessel, detachment of cells for scale up, optimization of infection, as well as harvest of virus particles. Microcarriers greatly increase the surface area for adherent cells and offer flexibility for expansion to bioreactors, but scale-up methods require optimization of bead-to-bead transfer. Even though the majority of cell culture based vaccines are produced with adherent cell lines, literature provides limited information in regards to optimization of adherent cell line processes. Some process improvements have been achieved; for example, recent advances in serum free media which no longer require medium exchange prior to virus infection. In this study we focus on the production of the rabies virus surrogate, vesicular stomatitis virus, in Vero cells. Using Cytodex-1 microcarriers in spinner flasks, we evaluated effects of intermittent and continuous stirring, detachment of cells, variation in the addition of new microcarriers on the growth of Vero cells, and effects on vesicular stomatitis virus production. Viable cell density measurements revealed that initial intermittent stirring resulted in increased cell densities compared to continuous stirring after microcarrier addition. In an effort to further simplify the process, we demonstrate that detachment of cells was not required to facilitate bead-to-bead transfer on Cytodex-1 microcarriers

Fact book on aging in British Columbia, 2nd Edition

Table of Contents1. Size of the Elderly Population;1.1 Past Trends and Future Growth; 1.2 Population Aging Within the Older Population Itself; 1.3 Median Age of the Population; 2. Sex Ratios; 3. Mortality; 3.1 Trends in Life Expectancy; 3.2 Mortality Rates; 3.3 Causes of Death; 4. Marital Status; 5. Geographic Distribution and Mobility; 5.1 The Older Population of B.C. in Relation to Other Provinces; 5.2 Rural-Urban Distribution; 5.3 Geographic Distribution Within British Columbia; 5.3.1 Geographic Distribution Within the Greater Vancouver Regional District; 5.3.2 Geographic Distribution Within the Capital Regional District; 5 .4 Mobility; 4.1 Total Population and Population Aged 65+; 5.4.2 Distance Moved; 6. Ethnic Composition; 6.1 Predominant Groups; 6.2 Proportion of Ethnic Origin Groups Aged 65+; 6.3 Aboriginal People; 7. Living Arrangements; 7.1 Persons by Type; 7.2 Private Households - Present and Future; 8. Housing; 8.1 Home Ownership; 8.2 Preferred Structural Type; 8.3 Housing Costs; 9. Education; 9.1 Educational Attainment; 10. Labour Force; 10.1 Labour Force Participation Trends; 10.2 Full and Part-time Employment; 11 Income; 11.1 Median Income of Individuals; 11.2 Poverty Rate; 12 Disabilities;12.1 Disability Rates; 12.2 Seniors with Disabilities in Private Households and Institutions; 12.3 Nature of Disabilities; 12.4 Severity of Disabilities; 13 Health Service; 13.1 Hospitals; 13.2 Continuing Care; Appendix

Visual identification of individual Holstein-Friesian cattle via deep metric learning

Holstein-Friesian cattle exhibit individually-characteristic black and white coat patterns visually akin to those arising from Turing's reaction-diffusion systems. This work takes advantage of these natural markings in order to automate visual detection and biometric identification of individual Holstein-Friesians via convolutional neural networks and deep metric learning techniques. Existing approaches rely on markings, tags or wearables with a variety of maintenance requirements, whereas we present a totally hands-off method for the automated detection, localisation, and identification of individual animals from overhead imaging in an open herd setting, i.e. where new additions to the herd are identified without re-training. We propose the use of SoftMax-based reciprocal triplet loss to address the identification problem and evaluate the techniques in detail against fixed herd paradigms. We find that deep metric learning systems show strong performance even when many cattle unseen during system training are to be identified and re-identified - achieving 98.2% accuracy when trained on just half of the population. This work paves the way for facilitating the non-intrusive monitoring of cattle applicable to precision farming and surveillance for automated productivity, health and welfare monitoring, and to veterinary research such as behavioural analysis, disease outbreak tracing, and more. Key parts of the source code, network weights and underpinning datasets are available publicly.Comment: 37 pages, 14 figures, 2 tables; Submitted to Computers and Electronics in Agriculture; Source code and network weights available at https://github.com/CWOA/MetricLearningIdentification; OpenCows2020 dataset available at https://doi.org/10.5523/bris.10m32xl88x2b61zlkkgz3fml1