Malaria-filaria coinfection in mice makes malarial disease more severe unless filarial infection achieves patency

Coinfections are common in natural populations, and the literature suggests that helminth coinfection readily affects how the immune system manages malaria. For example, type 1–dependent control of malaria parasitemia might be impaired by the type 2 milieu of preexisting helminth infection. Alternatively, immunomodulatory effects of helminths might affect the likelihood of malarial immunopathology. Using rodent models of lymphatic filariasis (Litomosoides sigmodontis) and noncerebral malaria (clone AS Plasmodium chabaudi chabaudi), we quantified disease severity, parasitemia, and polyclonal splenic immune responses in BALB/c mice. We found that coinfected mice, particularly those that did not have microfilaremia (Mf), had more severe anemia and loss of body mass than did mice with malaria alone. Even when controlling for parasitemia, malaria was most severe in Mf coinfected mice, and this was associated with increased interferon-g responsiveness. Thus, in Mf mice, filariasis upset a delicate immunological balance in malaria infection and exacerbated malaria-induced immunopathology. Helminth infections are prevalent throughout tropical regions where malaria is transmitted [1–5]. Interactions among infections commonly alter disease severity [6, 7], and malaria-helminth coinfection can either exac

Interpreting Dark Matter Direct Detection Independently of the Local Velocity and Density Distribution

We demonstrate precisely what particle physics information can be extracted from a single direct detection observation of dark matter while making absolutely no assumptions about the local velocity distribution and local density of dark matter. Our central conclusions follow from a very simple observation: the velocity distribution of dark matter is positive definite, f(v) >= 0. We demonstrate the utility of this result in several ways. First, we show a falling deconvoluted recoil spectrum (deconvoluted of the nuclear form factor), such as from ordinary elastic scattering, can be "mocked up" by any mass of dark matter above a kinematic minimum. As an example, we show that dark matter much heavier than previously considered can explain the CoGeNT excess. Specifically, m_chi < m_Ge} can be in just as good agreement as light dark matter, while m_\chi > m_Ge depends on understanding the sensitivity of Xenon to dark matter at very low recoil energies, E_R ~ 6 keVnr. Second, we show that any rise in the deconvoluted recoil spectrum represents distinct particle physics information that cannot be faked by an arbitrary f(v). As examples of resulting non-trivial particle physics, we show that inelastic dark matter and dark matter with a form factor can both yield such a rise

Bimodule structure in the periodic gl(1|1) spin chain

This paper is second in a series devoted to the study of periodic super-spin chains. In our first paper at 2011, we have studied the symmetry algebra of the periodic gl(1|1) spin chain. In technical terms, this spin chain is built out of the alternating product of the gl(1|1) fundamental representation and its dual. The local energy densities - the nearest neighbor Heisenberg-like couplings - provide a representation of the Jones Temperley Lieb (JTL) algebra. The symmetry algebra is then the centralizer of JTL, and turns out to be smaller than for the open chain, since it is now only a subalgebra of U_q sl(2) at q=i, dubbed U_q^{odd} sl(2). A crucial step in our associative algebraic approach to bulk logarithmic conformal field theory (LCFT) is then the analysis of the spin chain as a bimodule over U_q^{odd} sl(2) and JTL. While our ultimate goal is to use this bimodule to deduce properties of the LCFT in the continuum limit, its derivation is sufficiently involved to be the sole subject of this paper. We describe representation theory of the centralizer and then use it to find a decomposition of the periodic gl(1|1) spin chain over JTL for any even number N of tensorands and ultimately a corresponding bimodule structure. Applications of our results to the analysis of the bulk LCFT will then be discussed in the third part of this series.Comment: latex, 42 pp., 13 figures + 5 figures in color, many comments adde

Multiscale Modeling of Buoyant Fires

PresentationThe use of computational fluid dynamics (CFD) for understanding the fire hazard potential, can be an alternative to experimental studies for the process safety industry. Detailed experimental measurements are available for some lab-scale and medium-scale fires, however, large-scale fire experiments are significantly more difficult and expensive to conduct and availability of detailed experimental data is scarcer. Furthermore, applicability of available test data to industrial applications is sometimes difficult due to differences (geometry, flow conditions etc.) between the scenario under investigation and that considered during the experiments. Therefore, availability of a reliable technique that can overcome the above shortcomings (cost of experiments, and uncertainties about applicability) could bring benefits to the process safety industry. The performance of the CFD models in predicting the characteristics of buoyant fires depends on how adequately the fluid dynamics, chemical kinetics, and heat transfer mechanisms in these systems are modeled. In this study, the commercial software package STAR-CCM+ is used for modeling fires of differentsizes. The CFD models used in this study are first validated by comparing numerical results against the available experimental data for these fires. The validated models are then used to demonstrate a large- scale fire scenario. First, axial distribution of temperature and velocity from the Lab-scale experiments of purely buoyant diffusion flames of different heat release rates are compared between CFD simulations and experiments. The CFD model is able to capture the three regimes seen in these flames: (a) a continuous flame region, (b) an intermittent regime, and (c) the plume region. Next, a medium-scale 1m diameter pool fire is modeled, where the mean species concentrations, temperature, and velocity fields are compared with experimental measurements. Finally, a large-scale pool fire scenario is demonstrated using the same modeling approach. Detailed temporal and spatial information of the fire characteristics such as temperature and species concentration distribution, and radiative fluxes from this fire can be easily extracted from the CFD model, which would otherwise be difficult to obtain from field data. CFD simulations can thus be considered as a valuable tool for understanding the fire dynamics under various scenarios and be used to help devise appropriate safety strategies

PolySTRAND Model of Flow-Induced Nucleation in Polymers

We develop a thermodynamic continuum-level model, polySTRAND, for flow-induced nucleation in polymers suitable for use in computational process modeling. The model’s molecular origins ensure that it accounts properly for flow and nucleation dynamics of polydisperse systems and can be extended to include effects of exhaustion of highly deformed chains and nucleus roughness. It captures variations with the key processing parameters, flow rate, temperature, and molecular weight distribution. Under strong flow, long chains are over-represented within the nucleus, leading to superexponential nucleation rate growth with shear rate as seen in experiments

Small angle neutron scattering observation of chain retraction after a large step deformation

The process of retraction in entangled linear chains after a fast nonlinear stretch was detected from time-resolved but quenched small angle neutron scattering (SANS) experiments on long, well-entangled polyisoprene chains. The statically obtained SANS data cover the relevant time regime for retraction, and they provide a direct, microscopic verification of this nonlinear process as predicted by the tube model. Clear, quantitative agreement is found with recent theories of contour length fluctuations and convective constraint release, using parameters obtained mainly from linear rheology. The theory captures the full range of scattering vectors once the crossover to fluctuations on length scales below the tube diameter is accounted for

Promoting environmental management in very small businesses through “Green Angels” in a local collaborative partnership: a case study from Brighton, England

This paper describes the results of the East Brighton Employment and Environment Centre (EBEEC), a 15 month URBAN project, promoting environmental management to very small businesses in east Brighton, England. Some 31 volunteers, termed `Green Angels`, were trained in waste minimisation at the University of Brighton, and provided practical support to local firms through site reviews and research. The EBEEC project provided information and support to some 600 SMEs in east Brighton, via newsletters, email, telephone helpline, seminars and other projects. The Project was managed by a collaborative partnership formed from regional as well as local organisations. The involvement of a University to train potential `Green Angels`, so as to support SMEs in an area designated for economic regeneration, was an innovative and successful method of providing environmental management support to small firms. To stimulate the uptake of environmental management, case study material based on Best Practice was produced and disseminated to local companies via an Internet Site. A CD-Rom containing the Green Angel training package has been produced to help other projects like this. The outcomes from this Project will inform the regional and potentially the national approach to providing environmental business support and advice via local collaborative partnerships containing Universities

Enlarged symmetry algebras of spin chains, loop models, and S-matrices

The symmetry algebras of certain families of quantum spin chains are considered in detail. The simplest examples possess m states per site (m\geq2), with nearest-neighbor interactions with U(m) symmetry, under which the sites transform alternately along the chain in the fundamental m and its conjugate representation \bar{m}. We find that these spin chains, even with {\em arbitrary} coefficients of these interactions, have a symmetry algebra A_m much larger than U(m), which implies that the energy eigenstates fall into sectors that for open chains (i.e., free boundary conditions) can be labeled by j=0, 1, >..., L, for the 2L-site chain, such that the degeneracies of all eigenvalues in the jth sector are generically the same and increase rapidly with j. For large j, these degeneracies are much larger than those that would be expected from the U(m) symmetry alone. The enlarged symmetry algebra A_m(2L) consists of operators that commute in this space of states with the Temperley-Lieb algebra that is generated by the set of nearest-neighbor interaction terms; A_m(2L) is not a Yangian. There are similar results for supersymmetric chains with gl(m+n|n) symmetry of nearest-neighbor interactions, and a richer representation structure for closed chains (i.e., periodic boundary conditions). The symmetries also apply to the loop models that can be obtained from the spin chains in a spacetime or transfer matrix picture. In the loop language, the symmetries arise because the loops cannot cross. We further define tensor products of representations (for the open chains) by joining chains end to end. The fusion rules for decomposing the tensor product of representations labeled j_1 and j_2 take the same form as the Clebsch-Gordan series for SU(2). This and other structures turn the symmetry algebra \cA_m into a ribbon Hopf algebra, and we show that this is ``Morita equivalent'' to the quantum group U_q(sl_2) for m=q+q^{-1}. The open-chain results are extended to the cases |m|< 2 for which the algebras are no longer semisimple; these possess continuum limits that are critical (conformal) field theories, or massive perturbations thereof. Such models, for open and closed boundary conditions, arise in connection with disordered fermions, percolation, and polymers (self-avoiding walks), and certain non-linear sigma models, all in two dimensions. A product operation is defined in a related way for the Temperley-Lieb representations also, and the fusion rules for this are related to those for A_m or U_q(sl_2) representations; this is useful for the continuum limits also, as we discuss in a companion paper

A comparison of strength and power characteristics prior to anterior cruciate ligament rupture and at the end of rehabilitation in professional soccer players

Background: Strength and power is often reduced on the involved vs. contralateral limb and healthy controls following anterior cruciate ligament (ACL) reconstruction but no study has compared to pre-injury values at the time of return to sport (RTS). Hypothesis: Divergent recovery patterns in strength and power characteristics will be present at RTS relative to pre-injury baseline data and healthy matched controls. Study design: Cohort study Level of evidence: Level 3 Methods: Isokinetic strength tests, bilateral and single leg countermovement jumps (CMJ; SLCMJ) were measured prior to ACL rupture in 20 professional soccer players. These then had surgical reconstruction (ACL group) and completed follow up testing prior to RTS. Healthy controls (uninjured group) were tested at the same time as the ACL group pre-injury. Values recorded at RTS of the ACL group were compared to pre-injury. We also compared the uninjured and ACL groups at baseline and RTS. Results: Compared to pre-injury, ACL normalised quadriceps peak torque of the involved limb (% difference = -7%), SLCMJ height (% difference = -12.08%) and Reactive Strength Index modified (RSImod) (% difference = -5.04%) were reduced following ACL reconstruction. No significant reductions in CMJ height, RSImod and relative peak power were indicated at RTS in the ACL group when compared to pre-injury values but deficits were present relative to controls. The uninvolved limb significantly improved quadriceps (% difference = 9.34%) and hamstring strength (% difference = 7.36%) from pre-injury to RTS. No significant differences from baseline were shown in SLCMJ height, power and reactive strength of the uninvolved limb following ACL reconstruction. Conclusion: Strength and power in professional soccer players at RTS following ACL reconstruction were often reduced compared to preinjury values and matched healthy controls. Clinical relevance: Deficits were more apparent in the SLCMJ suggesting dynamic and multijoint unilateral force production is an important component of rehabilitation. Use of the uninvolved limb and normative data to determine recovery may not always be appropriate