Stable and unstable regimes in Bose-Fermi mixture with attraction between components

A collapse of the trapped boson- fermion mixture with the attraction between bosons and fermions is investigated in the framework of the effective Hamiltonian for the Bose system. The properties of the $^{87}$Rb and $^{40}$K mixture are analyzed quantitatively at $T= 0$. We find numerically solutions of modified Gross- Pitaevskii equation which continuously go from stable to unstable branch. We discuss the relation of the onset of collapse with macroscopic properties of the system. A comparison with the case of a Bose condensate of atomic $^7Li$ system is given.Comment: 7 pages, 5 figure

Membership, stability and internal institutions in European cartels

The first topic this thesis examines is that of firms which enter and leave cartels without affecting the existence of the cartel. The first chapter predicts which firms in markets will choose to join and leave cartels. The findings align with a group of theoretical models identified in the literature review, indicating that cartel membership is explained by�firms' individual preferences for collusion, which are consistent over time. The firms most likely to join and leave cartels are small firms in large cartels. The second chapter questions what effect this behaviour by firms has on the survivability of cartels. Theory is ambiguous on this, since entry and exit by firms could signal poor discipline among cartelists which prevents the cartel from raising prices substantially due to undercutting by outsiders or it could signal a structurally stable cartel which marginal firms take advantage of in their membership decisions. Cartels which experienced more entry and exit by firms had a lower risk of breakdown in each period than cartels with more static membership, indicating that member firms recognise when cartels are strong and take advantage of this by constantly re-evaluating their membership decisions. The�final chapter discusses a different topic: the types of agreement formed by cartels. All cartels must agree to either �x prices, restrict the output of its members, allocate exclusive territories, allocation customers, or rig bids in order to fulfil their objective of raising member profits. Many cartels engage in more than one of these practices simultaneously. Structural variables are poor at predicting the presence of agreement types in the cartels studied, but distinct strategy pro�les where certain agreement types substitute for each other or complement each other are present. These strategy profiles appear to be associated with particular industries and cartels of common geographical scope

Anonymity and the stigmatised subject : exploring the face and voice of the sex worker in documentary film practice

Mapping the representational and material dangers of participating as a sex worker in documentary film practice is the central purpose of this thesis. Argued here is that the totalising and dispossessive treatment of the sex worker plays out through topographies of their face and voice. Conversely, this thesis locates practices of voice and face that counter stigma, rhetorical silencing and disciplinary operations of power enacted through the documentary lens. This thesis is undertaken through practice-integrated research, whereby creative documentary practice connects and is used in tandem with other methods. Also combining textual analysis, documentary case studies, and research interviews with sex workers who have taken part in documentary anonymously, the intervention is to argue that the marginal subject of this thesis requires a schizoanalytic methodology. Adopting feminist methods of situated knowledges, the thesis addresses voice and spectatorship from the perspective of sex worker documentary subjects themselves. This analysis finds that while coming into voice as a marginalised subject signifies power, how one comes to that voice, and how it is heard, remains complex. Further, strategies of blurring, voice distortion and even disembodiment which facilitate sex worker voice are prone to the amplifying social abjection of sex work and facilitating pseudo-proxies covering over sex worker subjectivity. Arguing that anonymity itself is prone to failure, and that this is widely understood by sex workers, as is the representational volatility of that anonymity, the thesis counters that anonymity should be understood as a practice rather than as something one attains. Nonetheless, this translucency of identity can enable vulnerable subjects to speak

Evaluation of pre-analytical factors affecting plasma DNA analysis.

Pre-analytical factors can significantly affect circulating cell-free DNA (cfDNA) analysis. However, there are few robust methods to rapidly assess sample quality and the impact of pre-analytical processing. To address this gap and to evaluate effects of DNA extraction methods and blood collection tubes on cfDNA yield and fragment size, we developed a multiplexed droplet digital PCR (ddPCR) assay with 5 short and 4 long amplicons targeting single copy genomic loci. Using this assay, we compared 7 cfDNA extraction kits and found cfDNA yield and fragment size vary significantly. We also compared 3 blood collection protocols using plasma samples from 23 healthy volunteers (EDTA tubes processed within 1 hour and Cell-free DNA Blood Collection Tubes processed within 24 and 72 hours) and found no significant differences in cfDNA yield, fragment size and background noise between these protocols. In 219 clinical samples, cfDNA fragments were shorter in plasma samples processed immediately after venipuncture compared to archived samples, suggesting contribution of background DNA by lysed peripheral blood cells. In summary, we have described a multiplexed ddPCR assay to assess quality of cfDNA samples prior to downstream molecular analyses and we have evaluated potential sources of pre-analytical variation in cfDNA studies

Factors Associated with the Acquisition and Severity of Gestational Listeriosis

Gravid mammals are more prone to listeriosis than their nongravid counterparts. However, many features of the disease in gravid animals are not well defined. We determined, in mice, that increased susceptibility to lethal infection following oral inoculation begins surprisingly early in pregnancy and extends through embryonic development. Pregnancy did not demonstrably increase the spread of listeriae from the intestine to the liver and spleen in the initial 96 h period post inoculation. Consequently, it appeared that gravid animals were competent to contain an enteric infection, but in those instances where escape did occur, a lethal outcome was more likely. Interestingly, colonic colonization level and prevalence, measured 96 h post inoculation, was significantly higher in gravid individuals. In terms of human risk factors for listeriosis, our results suggest that the window of listeriosis susceptibility afforded by pregnancy may be open longer than previously appreciated. Our results also suggest that while gravid animals are competent to contain an enteric infection, enteric carriage rate may be more of a factor in defining disease incidence than previously considered

Extrauterine listeriosis in the gravid mouse influences embryonic growth and development

Gravid mice and other rodents inoculated with Listeria monocytogenes typically fail to clear an intrauterine infection and either succumb or expel their intrauterine contents. We took advantage of this property to investigate the effects of an extrauterine infection on parameters of pregnancy success. Pregnant mice were selected for our study if they showed no clinical signs of listeriosis following oral inoculation at 7.5 gestational days (gd), and had no detectable intrauterine colony forming units (cfu) at near term (18.5 gd). The range of oral doses employed was 10(6)-10(8) cfu per mouse for two listerial serotype strains (4nonb and 1/2a). At all doses, inoculation resulted in a decrease in average near-term (18.5 gd) fetal weight per litter compared to sham inoculated controls. Additionally, embryonic death (indicated by intrauterine resorptions) was exhibited by some inoculated mice but was absent in all sham inoculated animals. In parallel experiments designed to detect possible loss of placental function, gravid uteruses were examined histopathologically and microbiologically 96 h after oral inoculation. Placental lesions were associated with high (> 10(6)), but not low (< 10(2)) or absent intrauterine cfu. In vitro, mouse embryonic trophoblasts were indistinguishable from mouse enterocytes in terms of their sensitivity to listerial exposure. A model consistent with our observations is one in which products (host or bacterial) generated during an acute infection enter embryos transplacentally and influences embryonic survival and slows normal growth in utero

Hybrid phoneme based clustering approach for audio driven facial animation

We consider the problem of producing accurate facial animation corresponding to a given input speech signal. A popular technique previously used for Audio Driven Facial Animation is to build a joint audio-visual model using Active Appearance Models (AAMs) to represent possible facial variations and Hidden Markov Models (HMMs) to select the correct appearance based on the input audio. However there are several questions that remained unanswered. In particular the choice of clustering technique and the choice of the number of clusters in the HMM may have significant influence over the quality of the produced videos. We have investigated a range of clustering techniques in order to improve the quality of the HMM produced, and proposed a new structure based on using Gaussian Mixture Models (GMMs) to model each phoneme separately. We compared our approach to several alternatives using a public dataset of 300 phonetically labeled sentences spoken by a single person and found that our approach produces more accurate animation. In addition, we use a hybrid approach where the training data is phonetically labeled thus producing a model with better separation of phonemes, but test audio data is not labeled, thus making our approach for generating facial animation less laborious and fully automatic

Mycobacterial 65-kD heat shock protein induces release of proinflammatory cytokines from human monocytic cells

Monocytes having phagocytosed mycobacteria are known to present the bacterial 65-kD heat shock protein (hsp) on their cell surface to ΑΒ and ΓΔ T lymphocytes. Cytotoxic CD4 + cells may then lyse monocytes expressing mycobacterial 65-kD hsp. However, it is not known whether 65-kD hsp directly stimulates monocyte functions other than antigen presentation. This study has demonstrated that following extraction of bacterial lipopolysaccharide, purified recombinant mycobacterial 65-kD hsp may directly activate THP-1 cells, a human monocytic line, to accumulate mRNA for and secrete tumour necrosis factor (TNF), a cytokine important in granuloma formation, the characteristic host immune response to mycobacterial infection. TNF gene expression and secretion following stimulation by hsp was dose-dependent and abolished by heat-induced proteolysis. Subsequently, THP-1 cells secreted IL-6 and IL-8, cytokines involved in recruitment and differentiation of T lymphocytes. The data indicate that secretion of proinflammatory cytokines from monocytes activated by mycobacterial 65-kD hsp may be important in the host immune response and in the development of antigen-specific T cell-mediated immunity.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72917/1/j.1365-2249.1993.tb03354.x.pd