PHOTOS Interface in C++; Technical and Physics Documentation

For five years now, PHOTOS Monte Carlo for bremsstrahlung in the decay of particles and resonances has been available with an interface to the C++ HepMC event record. The main purpose of the present paper is to document the technical aspects of the PHOTOS Monte Carlo installation and present version use. A multitude of test results and examples are distributed together with the program code. The PHOTOS C++ physics precision is better than its FORTRAN predecessor and more convenient steering options are also available. An algorithm for the event record interface necessary for process dependent photon emission kernel is implemented. It is used in Z and W decays for kernels of complete first order matrix elements of the decays. Additional emission of final state lepton pairs is also available. Physics assumptions used in the program and properties of the solution are reviewed. In particular, it is explained how the second order matrix elements were used in design and validation of the program iteration procedure. Also, it is explained that the phase space parametrization used in the program is exact.Comment: Updated version; for the program as of April 201

Prevention of osteoporotic refractures in regional Australia

Objective: Clinical guidelines recommend that patients who sustain a minimal trauma fracture (MTF) should receive a bone mineral density (BMD) scan and bisphosphonate (or equivalent) therapy if diagnosed with osteoporosis. A pilot fracture liaison service (FLS) was implemented in regional NSW to improve adherence to the guidelines. Design: Prospective cohort study with an historical control. Setting: Primary care. Participants: Control (n = 47) and cohort (n = 93) groups comprised patients consenting to interview who presented with a MTF to the major referral hospital 4 months before and 12 months after FLS implementation respectively. Main outcome measures: Primary outcome measures were the rates of BMD scans and anti-osteoporotic medication initiation/review after MTF. Hospital admission data were also examined to determine death and refracture rates for all patients presenting during the study period with a primary diagnosis of MTF within 3 years of their initial fracture. Results: Although there was no improvement in BMD scanning rates, the reported rate of medication initiation/review after fracture was significantly higher (P \u3c 0.05) in the FLS cohort. However, once adjusted for age, this association was not significant (P = 0.086). There was a lower refracture rate during the cohort period (P = 0.013), however, there were significantly more deaths (P = 0.035) within 3 years of initial fracture. When deaths were taken into account via competing risk regression, patients in the cohort period were significantly less likely to refracture than those in the control period (Hazard ratio = 0.576, P = 0.032). Conclusions: A rurally based nurse-led FLS was associated with modest improvement after MTF. Consideration should be given to ways to strengthen the model of care to improve outcomes

Global limits on kinetic Alfv\'{e}non speed in quasineutral plasmas

Large amplitude kinetic Alfv\'{e}non (exact Alfv\'{e}n soliton) matching condition is investigated in quasineutral electron-ion and electron-positron-ion plasmas immersed in a uniform magnetic field. Using the standard pseudopotential method, the magnetohydrodynamics (MHD) equations are exactly solved and a global allowed matching condition for propagation of kinetic solitary waves is derived. It is remarked that, depending on the plasma parameters, the kinetic solitons can be sub- or super-Alfv\'{e}nic, in general. It is further revealed that, either upper or lower soliton speed-limit is independent of fractional plasma parameters. Furthermore, the soliton propagation angle with respect to that of the uniform magnetic field is found to play a fundamental role in controlling the soliton matching speed-range.Comment: To be published in Physics of Plasma

Utility of Lymph Node Aspiration in the Diagnosis of Visceral Leishmaniasis in Sudan.

We evaluated lymph node aspiration (LNA) as a simple diagnostic procedure for visceral leishmaniasis (VL). Lymph node aspiration was compared with the direct agglutination test (DAT) using a diagnostic titer > or = 1:6,400 in 7,880 suspected VL patients in eastern Sudan. Compared with DAT, LNA had a sensitivity of 65.1% (95% confidence interval = 63.5-66.6%). Parasite density in LNA correlated strongly with DAT titers (P < 0.0001), and low parasite density accounted for 78.1% of positive LNA results with DAT titers < 1:6,400 (n = 782). Risk factors predictive of a positive LNA result were an age of 1-29 years, male sex, a hemoglobin level < 10.0 g/dL, a DAT titer > or = 1:800, and a location with a higher prevalence of VL. Lymph node and splenic aspirations were similarly accurate as tests of cure after treatment of 50 VL patients in southern Sudan. Pre-treatment LNA results were negative in 20 cases of severe post kala-azar dermal leishmaniasis

TAUOLA for simulation of tau decay and production: perspectives for precision low energy and LHC applications

The status of Monte Carlo system for the simulation of tau-lepton production and decay in high-energy accelerator experiments is reviewed. Since previous tau-lepton conference in 2008 some practical modifications have been introduced: (i) For the TAUOLA Monte Carlo generator of tau-lepton decays, automated and simultaneous use of many versions of form-factors for the calculation of optional weights for fits was developped and checked to work in Belle and BaBar software environment. Work on alternative paramterizations of hadronic decays is advanced. (ii) the TAUOLA universal interface based on HepMC (the C++ event record) is now public. A similar interface for PHOTOS is now also public. (iii) Extension of PHOTOS Monte Carlo for QED bremsstrahlung in decays featuring kernels based on complete first order matrix element are gradually becoming widely available thanks to properites of the new, HepMC based interface. (iv) Tests of the programs systematized with the help of MC-TESTER are now available for FORTRAN and C++ users. Presented here results illustrate the status of the projects performed in collaboration with Nadia Davidson, Piotr Golonka, Gizo Nanava, Tomasz Przedzinski, Olga Shekhovtsova, El zbieta Richter-Was, Pablo Roig, Qingjun Xu and others.Comment: Presented at International workshop on Tau Lepton Physics, TAU10 Manchester GB, September, 2010,7 page

Field evaluation of rK39 test and direct agglutination test for diagnosis of visceral leishmaniasis in a population with high prevalence of human immunodeficiency virus in Ethiopia

Accuracy of an rK39 rapid diagnostic test (DiaMed-IT-Leish ) for visceral leishmaniasis (VL) was compared with splenic aspiration and the direct agglutination test (DAT) in a population with a high prevalence of infection with human immunodeficiency virus (HIV) in Ethiopia. There were 699 patients clinically suspected of having VL (153 parasitologically confirmed, 482 DAT confirmed, and 130 DAT negative), and 97 DAT-negative controls. A total of 84% were tested for HIV and 34% were HIV positive. Sensitivity of the rK39 test in parasitologically confirmed VL patients was 84% (77% in HIV positive and 87% in HIV negative; P = 0.25). Sensitivity of the DAT was higher (94%; P = 0.01), 89% in HIV-positive patients and 95% in HIV-negative patients; P = 0.27). Specificity of the rK39 test was 99% in DAT-negative controls and 92% in DAT-negative patients clinically suspected of having VL. A diagnostic algorithm combining DAT and the rK39 test had a sensitivity of 98% in HIV-positive VL patients and 99% in HIV-negative VL patients. Despite the lower sensitivity in a population with a high prevalence of HIV, the DiaMed-IT-Leish rK39 test enables decentralization of diagnosis. Patients clinically suspected of having VL who show negative results on the rK39 antigen test should undergo follow-up DAT testing, especially if they are HIV positive

The importance of clinically relevant background therapy in cardioprotective studies

Treatment of acute myocardial infarct patients (AMI) includes rapid restoration of coronary blood flow and pharmacological therapy aimed to prevent pain and maintain vessel patency. Many interventions have been investigated to offer additional protection. One such intervention is remote ischaemic conditioning (RIC) involving short-episodes of ischaemia of the arm with a blood pressure cuff, followed by reperfusion to protect the heart organs from subsequent severe ischaemia. However, the recent CONDI2-ERIC-PPCI multicentre study of RIC in STEMI showed no benefit in clinical outcome in low risk patients. It could also be argued that these patients were already in a partially protected state, highlighting the disconnect between animal- and clinical-based outcome studies. To improve potential translatability, we developed an animal model using pharmacological agents similar to those given to patients presenting with an AMI, prior to PPCI. Rats underwent MI on a combined background of an opioid agonist, heparin and a platelet-inhibitor thereby allowing us to assess whether additional cardioprotective strategies had any effect over and above this “cocktail”. We demonstrated that the “background drugs” were protective in their own right, reducing MI from 57.5 ± 3.7% to 37.3 ± 2.9% (n = 11, p < 0.001). On this background of drugs, RIC did not add any further protection (38.0 ± 3.4%). However, using a caspase inhibitor, which acts via a different mechanistic pathway to RIC, we were able to demonstrate additional protection (20.6 ± 3.3%). This concept provides initial evidence to develop models which can be used to evaluate future animal-to-clinical translation in cardioprotective studies

MC-TESTER v. 1.23: a universal tool for comparisons of Monte Carlo predictions for particle decays in high energy physics

Theoretical predictions in high energy physics are routinely provided in the form of Monte Carlo generators. Comparisons of predictions from different programs and/or different initialization set-ups are often necessary. MC-TESTER can be used for such tests of decays of intermediate states (particles or resonances) in a semi-automated way. Since 2002 new functionalities were introduced into the package. In particular, it now works with the HepMC event record, the standard for C++ programs. The complete set-up for benchmarking the interfaces, such as interface between tau-lepton production and decay, including QED bremsstrahlung effects is shown. The example is chosen to illustrate the new options introduced into the program. From the technical perspective, our paper documents software updates and supplements previous documentation. As in the past, our test consists of two steps. Distinct Monte Carlo programs are run separately; events with decays of a chosen particle are searched, and information is stored by MC-TESTER. Then, at the analysis step, information from a pair of runs may be compared and represented in the form of tables and plots. Updates introduced in the progam up to version 1.24.3 are also documented. In particular, new configuration scripts or script to combine results from multitude of runs into single information file to be used in analysis step are explained.Comment: 27 pages 4 figure

Weak turbulence theory of the non-linear evolution of the ion ring distribution

The nonlinear evolution of an ion ring instability in a low-beta magnetospheric plasma is considered. The evolution of the two-dimensional ring distribution is essentially quasilinear. Ignoring nonlinear processes the time-scale for the quasilinear evolution is the same as for the linear instability 1/t_ql gamma_l. However, when nonlinear processes become important, a new time scale becomes relevant to the wave saturation mechanism. Induced nonlinear scattering of the lower-hybrid waves by plasma electrons is the dominant nonlinearity relevant for plasmas in the inner magnetosphere and typically occurs on the timescale 1/t_ql w(M/m)W/nT, where W is the wave energy density, nT is the thermal energy density of the background plasma, and M/m is the ion to electron mass ratio, which has the consequence that the wave amplitude saturates at a low level, and the timescale for quasilinear relaxation is extended by orders of magnitude

Unified Universal Seesaw Models

A set of Grand Unified Theories based upon the gauge groups SU(5)_\L \times SU(5)_\R, SO(10)_\L \times SO(10)_\R and SU(4)_\C \times SU(4)_\L \times SU(4)_\R is explored. Several novel features distinguish these theories from the well-known $SU(5)$, $SO(10)$ and SU(4)_\C \times SU(2)_\L \times SU(2)_\R models which they generalize. Firstly, Standard Model quarks and leptons are accompanied by and mix with heavy SU(2)_\L \times SU(2)_\R singlet partners. The resulting fermion mass matrices are seesaw in form. Discrete parity symmetries render the determinants of these mass matrices real and eliminate CP violating gauge terms. The unified seesaw models consequently provide a possible resolution to the strong CP problem. Secondly, \sinsq at the unification scale is numerically smaller than the experimentally measured $Z$ scale value. The weak angle must therefore increase as it evolves down in energy. Finally, proton decay is suppressed by small seesaw mixing factors in all these theories.Comment: 22 pages with 2 figures not included but available upon request, CALT-68-185