Time-delayed feedback in neurosystems

The influence of time delay in systems of two coupled excitable neurons is studied in the framework of the FitzHugh-Nagumo model. Time-delay can occur in the coupling between neurons or in a self-feedback loop. The stochastic synchronization of instantaneously coupled neurons under the influence of white noise can be deliberately controlled by local time-delayed feedback. By appropriate choice of the delay time synchronization can be either enhanced or suppressed. In delay-coupled neurons, antiphase oscillations can be induced for sufficiently large delay and coupling strength. The additional application of time-delayed self-feedback leads to complex scenarios of synchronized in-phase or antiphase oscillations, bursting patterns, or amplitude death.Comment: 13 pages, 13 figure

A large Muon Electric Dipole Moment from Flavor?

We study the prospects and opportunities of a large muon electric dipole moment (EDM) of the order (10^{-24} - 10^{-22}) ecm. We investigate how natural such a value is within the general minimal supersymmetric extension of the Standard Model with CP violation from lepton flavor violation in view of the experimental constraints. In models with hybrid gauge-gravity mediated supersymmetry breaking a large muon EDM is indicative for the structure of flavor breaking at the Planck scale, and points towards a high messenger scale.Comment: 12 pages, 12 figures. v3: References and Eq 28 fixed; conclusions unchange

B_s ---> \gamma \gamma decay in the model III and 3HDM(O_2) with CP violating effects

We analyse the CP asymmetry for B_{s} -->\gamma\gamma in the two Higgs doublet model with tree level flavor changing currents (model III) and three Higgs doublet model with O_2 symmetry in the Higgs sector, including O_{7} type long distance effects. Further, we study the dependencies of the branching ratio Br(B_{s} --> \gamma\gamma)$ and the ratio of CP-even and CP-odd amplitude squares, R=|A^{+}|^2/|A^{-}|^2, on the CP parameter sin \theta. We found that, there is a weak CP asymmetry, at the order of 10^{-4}. Besides, the branching ratio Br(B_{s} --> \gamma\gamma), and also R ratio, is not sensitive to the CP parameter for |\frac{\bar{\xi}^{U}_{N,tt}}{\bar{\xi}^{D}_{N,bb}}|<1.Comment: 17 pages, 11 figure

Risk of basal cell carcinoma after Hodgkin's disease

Background: Basal cell cancer is a common skin cancer, yet studies of second tumors after Hodgkin's disease tend to exclude basal cell cancers as second malignant tumors from analysis. Basal cell carcinomas (BCC) are possibly more common in immunosuppressed patients and were recently implicated as indicators of subsequent malignancies. Materials and Methods: Our database of 1,120 patients with Hodgkin's disease (derived from the tumor registry) was investigated for the occurrence of later BCCs. Kaplan-Meier curves were calculated. Results: A total of 9 cases of BCC were observed 0-20 years after the diagnosis of Hodgkin's disease, One case relapsed after excision. The probability of second BCC was 2.1% after 15 years of follow-up and 7.1% after 20 years. Statistically, the risk for second BCC was increased only in younger patients and with prolonged follow-up, but not in the total group of patients with Hodgkin's disease. Conclusion: BCC is not a major threat: for the survivors of Hodgkin's disease, but continued follow-up is necessary

Forming norms: informing diagnosis and management in sports medicine

Clinicians aim to identify abnormalities, and distinguish harmful from harmless abnormalities. In sports medicine, measures of physical function such as strength, balance and joint flexibility are used as diagnostic tools to identify causes of pain and disability and monitor progression in response to an intervention. Comparing results from clinical measures against ‘normal’ values guides decision-making regarding health outcomes. Understanding ‘normal’ is therefore central to appropriate management of disease and disability. However, ‘normal’ is difficult to clarify and definitions are dependent on context. ‘Normal’ in the clinical setting is best understood as an appropriate state of physical function. Particularly as disease, pain and sickness are expected occurrences of being human, understanding ‘normal’ at each stage of the lifespan is essential to avoid the medicalisation of usual life processes. Clinicians use physical measures to assess physical function and identify disability. Accurate diagnosis hinges on access to ‘normal’ reference values for such measures. However our knowledge of ‘normal’ for many clinical measures in sports medicine is limited. Improved knowledge of normal physical function across the lifespan will assist greatly in the diagnosis and management of pain, disease and disability

Efficacy of Two Raccoon Eviction Fluids

According to surveys of wildlife control operators (WCO), problems with raccoons (Procyon lotor) consistently rank among the top complaints for property owners. Among the more serious behaviors of female raccoons is their propensity to invade human-occupied structures to raise young. Distressed property owners frequently respond using lethal means, either on their own or through hiring WCOs. Even if live-captured and legally released, the handling of raccoons may result in injuries and potentially cause females to abandon young. Eviction fluids, developed in the early 1990s, are designed to smell like a male raccoon and therefore cause a nursing raccoon to leave the den with her young. Wildlife control operators use eviction fluid primarily to evict a female and her young from an inaccessible location. Though the precise formulas are not disclosed by manufacturers, the fluids consist of the glands and urine of male raccoons coupled with a preservative. We evaluated the efficacy of 2 raccoon eviction fluids to evict female raccoons with young from chimneys. Though our sample size was small (n =15), we found that eviction fluids merit further investigation as a viable non-lethal repellent for raccoons in human-occupied structures

Symmetries and Ambiguities in the linear sigma model with light quarks

We investigate the role of undetermined finite contributions generated by radiative corrections in a $SU(2)\times SU(2)$ linear sigma model with quarks. Although some of such terms can be absorbed in the renormalization procedure, one such contribution is left in the expression for the pion decay constant. This arbitrariness is eliminated by chiral symmetry.Comment: 9 pages. Added references through the text; an author was added due to an important contribution; corrected typos; the title also was changed. Submitted to Modern Physics Letter

Biosorption of arsenic and cadmium from aqueous solutions

The biosorption of cadmium and arsenic from aqueous solutions onto the unmodified compact biomass of microscopic filamentous fungus Aspergillus clavatus DESM. was studied in the concentrationrange of 0.25 – 100 mg.l-1. The experimental biosorption results for arsenic and cadmium followed well the Freundlich equilibrium sorption model