On unbalanced Boolean functions with best correlation immunity

It is known that the order of correlation immunity of a nonconstant unbalanced Boolean function in $n$ variables cannot exceed $2n/3-1$; moreover, it is $2n/3-1$ if and only if the function corresponds to an equitable $2$-partition of the $n$-cube with an eigenvalue $-n/3$ of the quotient matrix. The known series of such functions have proportion $1:3$, $3:5$, or $7:9$ of the number of ones and zeros. We prove that if a nonconstant unbalanced Boolean function attains the correlation-immunity bound and has ratio $C:B$ of the number of ones and zeros, then $CB$ is divisible by $3$. In particular, this proves the nonexistence of equitable partitions for an infinite series of putative quotient matrices. We also establish that there are exactly $2$ equivalence classes of the equitable partitions of the $12$-cube with quotient matrix $[[3,9],[7,5]]$ and $16$ classes, with $[[0,12],[4,8]]$. These parameters correspond to the Boolean functions in $12$ variables with correlation immunity $7$ and proportion $7:9$ and $1:3$, respectively (the case $3:5$ remains unsolved). This also implies the characterization of the orthogonal arrays OA$(1024,12,2,7)$ and OA$(512,11,2,6)$.Comment: v3: final; title changed; revised; OA(512,11,2,6) discusse

Radiated Immunity Testing of a Device with an External Wire: Repeatibility of Reverberation Chamber Results and Correlation with Anechoic Chamber Results

We present the experimental radiated immunity results of an electronic device with an external wire obtained in reverberation and anechoic chambers. Repeatability and reproducibility of reverberation chamber measurements are investigated by repeating the test in three reverberation chambers with different characteristics. We show how the current state of the art allows a statistical control of RC measurement repeatability within an industrial installation, and that a statistical correlation with AC results frequency by frequency is possible in particular cases relevant to automotive application

Crossover from Percolation to Self-Organized Criticality

We include immunity against fire as a new parameter into the self-organized critical forest-fire model. When the immunity assumes a critical value, clusters of burnt trees are identical to percolation clusters of random bond percolation. As long as the immunity is below its critical value, the asymptotic critical exponents are those of the original self-organized critical model, i.e. the system performs a crossover from percolation to self-organized criticality. We present a scaling theory and computer simulation results.Comment: 4 pages Revtex, two figures included, to be published in PR

Forest fires and other examples of self-organized criticality

We review the properties of the self-organized critical (SOC) forest-fire model. The paradigm of self-organized criticality refers to the tendency of certain large dissipative systems to drive themselves into a critical state independent of the initial conditions and without fine-tuning of the parameters. After an introduction, we define the rules of the model and discuss various large-scale structures which may appear in this system. The origin of the critical behavior is explained, critical exponents are introduced, and scaling relations between the exponents are derived. Results of computer simulations and analytical calculations are summarized. The existence of an upper critical dimension and the universality of the critical behavior under changes of lattice symmetry or the introduction of immunity are discussed. A survey of interesting modifications of the forest-fire model is given. Finally, several other important SOC models are briefly described.Comment: 37 pages RevTeX, 13 PostScript figures (Figs 1, 4, 13 are of reduced quality to keep download times small

Natural variation in immune responses to neonatal mycobacterium bovis bacillus calmette-guerin (BCG) vaccination in a cohort of Gambian infants

Background There is a need for new vaccines for tuberculosis (TB) that protect against adult pulmonary disease in regions where BCG is not effective. However, BCG could remain integral to TB control programmes because neonatal BCG protects against disseminated forms of childhood TB and many new vaccines rely on BCG to prime immunity or are recombinant strains of BCG. Interferon-gamma (IFN-) is required for immunity to mycobacteria and used as a marker of immunity when new vaccines are tested. Although BCG is widely given to neonates IFN- responses to BCG in this age group are poorly described. Characterisation of IFN- responses to BCG is required for interpretation of vaccine immunogenicity study data where BCG is part of the vaccination strategy. Methodology/Principal Findings 236 healthy Gambian babies were vaccinated with M. bovis BCG at birth. IFN-, interleukin (IL)-5 and IL-13 responses to purified protein derivative (PPD), killed Mycobacterium tuberculosis (KMTB), M. tuberculosis short term culture filtrate (STCF) and M. bovis BCG antigen 85 complex (Ag85) were measured in a whole blood assay two months after vaccination. Cytokine responses varied up to 10 log-fold within this population. The majority of infants (89-98% depending on the antigen) made IFN- responses and there was significant correlation between IFN- responses to the different mycobacterial antigens (Spearman’s coefficient ranged from 0.340 to 0.675, p=10-6-10-22). IL-13 and IL-5 responses were generally low and there were more non-responders (33-75%) for these cytokines. Nonetheless, significant correlations were observed for IL-13 and IL-5 responses to different mycobacterial antigens Conclusions/Significance Cytokine responses to mycobacterial antigens in BCG-vaccinated infants are heterogeneous and there is significant inter-individual variation. Further studies in large populations of infants are required to identify the factors that determine variation in IFN- responses

Vegetative, metabolic and immune accompaniments of changes in the electrokinetic index of the buccal epithelium under the influence of therapeutic factors

Background. In previous studies, we have shown that electrokinetic index of buccal epithelium (EKI) correlated with some functional and metabolic parameters. Subsequent studies have shown that сhanges in EKI correlated with changes in some parameters of EEG, HRV, hemodynamics, metabolism, immunity and fecal microbiocenosis. Further research in this direction was continued on a significantly increased contingent of patients and with the involvement of new methods and factors of influence. This message starts the presentation of the obtained results. Material and methods. Under a observations were 44 men (49±15 years) and 30 women (51±13 years) without clinical diagnosis or with chronic pyelonephritis in the phase of remission (23 men). We registered caused by the various therapeutic factors changes in EKI, state of the vegetative and hormonal regulation as well as immunity and metabolism, then calculated relationships between changes. Results. In 49 patients the changes in EKI were in the range of ±2,5%, in 19 people EKI increased by more than 2,5% (M±SD=+4,0±1,6%), while in 9 people decreased by more than 2,5% (-4,2±1,7%). The canonical correlation between changes in EKI, on the one hand, and HRV and immunity parameters, on the other, is moderate: R=0,478; p=0,023. The method of discriminant analysis revealed 10 immune and 6 HRV parameters as well as triglycerides and cholesterol, whose changes are characteristic of multidirectional changes in EKI. Conclusion. Electrokinetic index of buccal epithelium responds to therapeutic factors in different directions, accompanied by characteristic changes in a number of parameters of HRV, immunity and metabolism

Salivary immunity and lower respiratory tract infections in non-elite marathon runners

Peer ReviewedPostprint (published version

Characterization of Murine Breast Cancer Cell Lines for Anti-Cancer Vaccine

Breast cancer is the most commonly diagnosed cancer in women and the second leading cause of cancer death among women in the United States (1). While treatments involving radiation and chemotherapy currently exist, disease must be detected early in order for the treatments to be somewhat effective, and there is no effective treatment after metastasis occurs (2). Additionally, current therapies do not mitigate tumor immunosuppression. Decreasing the tumor-associated immunosuppressive conditions while activating antitumor immunity could prevent recurrence and metastasis, possibly leading to an effective treatment for cancer (3). Tumor cell vaccines could possibly address this issue and have become a recent topic of research. They have the potential to generate tumor regression and antitumor immune responses, but they have had low clinical response rates and poor immunogenicity so far (3, 4). We suspect the failure of cancer vaccines to be due to the immunosuppression and heterogeneity of breast cancers. Thus, to determine how and why different breast cancers induce different levels of immunosuppression, we studied different cancer cell lines of varying levels of immunogenicity. The study included five murine breast cancer cell lines, 4T1, 4T07, 66cl4, 168FARN, and 67NR. These are sister cell lines that were isolated from a Balb/cfC3H mouse and that differ in aggressiveness and metastatic capability. The production of immunosuppressive cytokines GM-CSF, G-CSF, M-CSF, IL-6, MCP-1, TGF-β, and VEGF was quantified for each of these cell lines. We also studied the effect these cytokines have on the expansion of myeloid-derived suppressor cells (MDSCs), which are known to suppress the immune response, and found that high levels of G-CSF are correlated with high numbers of MDSCs. A correlation between G-CSF levels and MDSC accumulation in these breast cancer cell lines could lead to future studies in which the effects of G-CSF are blocked in order to develop effective autologous breast cancer vaccines