Clostridium septicum aortitis with synchronous ascending colon and rectal adenocarcinoma.

Clostridium septicum (C. septicum) aortitis is a rare condition frequently associated with colon adenocarcinoma and carries a poor prognosis. We report the case of a 66-year-old man who presented with abdominal pain, blood in the stool, fever and chills. Laboratory tests were significant for leukocytosis and microcytic anemia. Abdominal imaging revealed a right colon mass and aortitis. Colonoscopy confirmed the right colon mass and also discovered a rectal mass, both adenocarcinomas. Treatment consisted of antibiotics, aortic repair, right hemi-colectomy and later trans-anal excision of the rectal mass. Blood cultures and the aortic specimen grew C. septicum. The patient improved and was doing well in follow up

Composite fermion wave functions as conformal field theory correlators

It is known that a subset of fractional quantum Hall wave functions has been expressed as conformal field theory (CFT) correlators, notably the Laughlin wave function at filling factor $\nu=1/m$ ($m$ odd) and its quasiholes, and the Pfaffian wave function at $\nu=1/2$ and its quasiholes. We develop a general scheme for constructing composite-fermion (CF) wave functions from conformal field theory. Quasiparticles at $\nu=1/m$ are created by inserting anyonic vertex operators, $P_{\frac{1}{m}}(z)$, that replace a subset of the electron operators in the correlator. The one-quasiparticle wave function is identical to the corresponding CF wave function, and the two-quasiparticle wave function has correct fractional charge and statistics and is numerically almost identical to the corresponding CF wave function. We further show how to exactly represent the CF wavefunctions in the Jain series $\nu = s/(2sp+1)$ as the CFT correlators of a new type of fermionic vertex operators, $V_{p,n}(z)$, constructed from $n$ free compactified bosons; these operators provide the CFT representation of composite fermions carrying $2p$ flux quanta in the $n^{\rm th}$ CF Landau level. We also construct the corresponding quasiparticle- and quasihole operators and argue that they have the expected fractional charge and statistics. For filling fractions 2/5 and 3/7 we show that the chiral CFTs that describe the bulk wave functions are identical to those given by Wen's general classification of quantum Hall states in terms of $K$-matrices and $l$- and $t$-vectors, and we propose that to be generally true. Our results suggest a general procedure for constructing quasiparticle wave functions for other fractional Hall states, as well as for constructing ground states at filling fractions not contained in the principal Jain series.Comment: 26 pages, 3 figure

Evolutionary dynamics of the most populated genotype on rugged fitness landscapes

We consider an asexual population evolving on rugged fitness landscapes which are defined on the multi-dimensional genotypic space and have many local optima. We track the most populated genotype as it changes when the population jumps from a fitness peak to a better one during the process of adaptation. This is done using the dynamics of the shell model which is a simplified version of the quasispecies model for infinite populations and standard Wright-Fisher dynamics for large finite populations. We show that the population fraction of a genotype obtained within the quasispecies model and the shell model match for fit genotypes and at short times, but the dynamics of the two models are identical for questions related to the most populated genotype. We calculate exactly several properties of the jumps in infinite populations some of which were obtained numerically in previous works. We also present our preliminary simulation results for finite populations. In particular, we measure the jump distribution in time and find that it decays as $t^{-2}$ as in the quasispecies problem.Comment: Minor changes. To appear in Phys Rev

Composition & Stability Constants of Diphenic Acid Complexes of Th(IV), Ce(IV), U(VI) & of Th(IV)-EDTA-Diphenic Acid Mixed Ligand Complex

1110-111

Pulsed x-rays dose measurements from a hundred joules plasma focus device

Indexación: Scopus.Present work is aimed to perform dosimetric measurements to characterize dosis obtained from pulsed x-rays emitted from a hundred joules plasma focus device PF-400J using thermoluminescent dosimeters (TLD-100). Two dosimeter arrays (containing 21 dosimeters in each) were used. One of the arrays was kept inside the PF-400J vacuum chamber and other outside the vacuum chamber, simultaneously. It was found that dosis obtained from the inside array (∼200.7 mGy) were hundred times larger than the outside array (∼1.1 mGy) for hundred pulses of x-rays. Later, the vacuum window of PF-400J, which was made of 1 mm aluminum, was replaced by a plastic window and a similar dosimeter array was kept outside the chamber over the plastic window. With this arrangement, the obtained doses (100 pulses of x-rays) were of the same order of magnitude (∼106 mGy) as it was inside the vacuum chamber. Later, a lead piece was inserted inside the hollow anode of PF-400J, which increased dose (∼250 mGy) per hundred pulses of x-ray outside the vacuum chamber using plastic vacuum window. Our results suggest that PF-400J could be a useful device to study low dose pulsed radiation effects on cancer cell lines in in vitro experiments. © Published under licence by IOP Publishing Ltd.The work is supported by grant ACT-1115, CONICYT, Chile.https://iopscience.iop.org/article/10.1088/1742-6596/1043/1/01204

Molecular dynamics simulation of polymer helix formation using rigid-link methods

Molecular dynamics simulations are used to study structure formation in simple model polymer chains that are subject to excluded volume and torsional interactions. The changing conformations exhibited by chains of different lengths under gradual cooling are followed until each reaches a state from which no further change is possible. The interactions are chosen so that the true ground state is a helix, and a high proportion of simulation runs succeed in reaching this state; the fraction that manage to form defect-free helices is a function of both chain length and cooling rate. In order to demonstrate behavior analogous to the formation of protein tertiary structure, additional attractive interactions are introduced into the model, leading to the appearance of aligned, antiparallel helix pairs. The simulations employ a computational approach that deals directly with the internal coordinates in a recursive manner; this representation is able to maintain constant bond lengths and angles without the necessity of treating them as an algebraic constraint problem supplementary to the equations of motion.Comment: 15 pages, 14 figure