Host Control of Malaria Infections: Constraints on Immune and Erythropoeitic Response Kinetics

The two main agents of human malaria, Plasmodium vivax and Plasmodium falciparum, can induce severe anemia and provoke strong, complex immune reactions. Which dynamical behaviors of host immune and erythropoietic responses would foster control of infection, and which would lead to runaway parasitemia and/or severe anemia? To answer these questions, we developed differential equation models of interacting parasite and red blood cell (RBC) populations modulated by host immune and erythropoietic responses. The model immune responses incorporate both a rapidly responding innate component and a slower-responding, long-term antibody component, with several parasite developmental stages considered as targets for each type of immune response. We found that simulated infections with the highest parasitemia tended to be those with ineffective innate immunity even if antibodies were present. We also compared infections with dyserythropoiesis (reduced RBC production during infection) to those with compensatory erythropoiesis (boosted RBC production) or a fixed basal RBC production rate. Dyserythropoiesis tended to reduce parasitemia slightly but at a cost to the host of aggravating anemia. On the other hand, compensatory erythropoiesis tended to reduce the severity of anemia but with enhanced parasitemia if the innate response was ineffective. For both parasite species, sharp transitions between the schizont and the merozoite stages of development (i.e., with standard deviation in intra-RBC development time ≤2.4 h) were associated with lower parasitemia and less severe anemia. Thus tight synchronization in asexual parasite development might help control parasitemia. Finally, our simulations suggest that P. vivax can induce severe anemia as readily as P. falciparum for the same type of immune response, though P. vivax attacks a much smaller subset of RBCs. Since most P. vivax infections are nonlethal (if debilitating) clinically, this suggests that P. falciparum adaptations for countering or evading immune responses are more effective than those of P. vivax

Search for anomalous t t-bar production in the highly-boosted all-hadronic final state

A search is presented for a massive particle, generically referred to as a Z', decaying into a t t-bar pair. The search focuses on Z' resonances that are sufficiently massive to produce highly Lorentz-boosted top quarks, which yield collimated decay products that are partially or fully merged into single jets. The analysis uses new methods to analyze jet substructure, providing suppression of the non-top multijet backgrounds. The analysis is based on a data sample of proton-proton collisions at a center-of-mass energy of 7 TeV, corresponding to an integrated luminosity of 5 inverse femtobarns. Upper limits in the range of 1 pb are set on the product of the production cross section and branching fraction for a topcolor Z' modeled for several widths, as well as for a Randall--Sundrum Kaluza--Klein gluon. In addition, the results constrain any enhancement in t t-bar production beyond expectations of the standard model for t t-bar invariant masses larger than 1 TeV.Comment: Submitted to the Journal of High Energy Physics; this version includes a minor typo correction that will be submitted as an erratu

Search for neutral MSSM Higgs bosons decaying to a pair of tau leptons in pp collisions

Peer reviewe

Measurement of top quark–antiquark pair production in association with a W or Z boson in pp collisions at √s=8 TeV

Peer reviewe

Searches for electroweak production of charginos, neutralinos, and sleptons decaying to leptons and W, Z, and Higgs bosons in pp collisions at 8 TeV

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Study of hadronic event-shape variables in multijet final states in pp collisions at √s=7 TeV

Peer reviewe

Measurement of prompt J/ψ pair production in pp collisions at √s = 7 Tev

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Constraints on parton distribution functions and extraction of the strong coupling constant from the inclusive jet cross section in pp collisions at √s=7 TeV

Peer reviewe

Structures of four- and six-coordinate monomers of [N,N '-bis(5-chlorosalicylidene)-1,3-diaminopropane]nickel(II)

WOS: 000165618200004[N,N' -Bis(5-chlorosalicylidene) -1,3 -diaminopropane] nickel(II) [Ni(C17H14N2O2Cl2)] 1 and [N,N' -Bis(5-chlorosalicylidene)-1,3 -diaminopropane] nickel(II) dihydrate [Ni(C17H14N2O2Cl2).2(H2O)] 2 were synthesized, and their crystal structures were determined. Compound 1 is monoclinic, space group C2/c, a = 21.063(4), b = 8.151(1), c = 9.421(2) Angstrom, beta = 94.16(1)degrees, V = 1613.2(5) Angstrom (3), Z = 4 and D-c = 1.680 g cm(-3). Compound 1 contains a crystallographic twofold axis, and the whole molecule is not planar. The two Schiff base moieties, which in themselves are planar, are twisted with respect to one another. The least-squares planes through each half of the molecule are inclined at an angle of 29.1(1)degrees. The Ni atom is in a square-planar environment. The Ni-N and Ni-O distances are 1.958(2) and 1.910(2) Angstrom, respectively. Compound 2 is orthorhombic, space group Pnma, with a = 7.892(1), b = 23.396(2), c = 9.992(1) Angstrom, V = 1846.3(3) Angstrom (3), Z = 4 and D-c = 1.597 g cm(-3). Compound 2 has crystallographic mirror symmetry, and again, the whole molecule is not planar. The two planar Schiff base moieties inclined at an angle of 38.7(1)degrees. The Ni atom is in a distorted octahedral geometry and coordinated by the donor atoms of the ligand in the horizontal plane, and the coordination sphere is completed by O atoms of two water molecules