On the String Consensus Problem and the Manhattan Sequence Consensus Problem

In the Manhattan Sequence Consensus problem (MSC problem) we are given $k$ integer sequences, each of length $l$, and we are to find an integer sequence $x$ of length $l$ (called a consensus sequence), such that the maximum Manhattan distance of $x$ from each of the input sequences is minimized. For binary sequences Manhattan distance coincides with Hamming distance, hence in this case the string consensus problem (also called string center problem or closest string problem) is a special case of MSC. Our main result is a practically efficient $O(l)$-time algorithm solving MSC for $k\le 5$ sequences. Practicality of our algorithms has been verified experimentally. It improves upon the quadratic algorithm by Amir et al.\ (SPIRE 2012) for string consensus problem for $k=5$ binary strings. Similarly as in Amir's algorithm we use a column-based framework. We replace the implied general integer linear programming by its easy special cases, due to combinatorial properties of the MSC for $k\le 5$. We also show that for a general parameter $k$ any instance can be reduced in linear time to a kernel of size $k!$, so the problem is fixed-parameter tractable. Nevertheless, for $k\ge 4$ this is still too large for any naive solution to be feasible in practice.Comment: accepted to SPIRE 201

Potentially modifiable predictors of adverse neonatal and maternal outcomes in pregnancies with gestational diabetes mellitus: can they help for future risk stratification and risk-adapted patient care?

Gestational diabetes mellitus (GDM) exposes mothers and their offspring to short and long-term complications. The objective of this study was to identify the importance of potentially modifiable predictors of adverse outcomes in pregnancies with GDM. We also aimed to assess the relationship between maternal predictors and pregnancy outcomes depending on HbA1c values and to provide a risk stratification for adverse pregnancy outcomes according to the prepregnancy BMI (Body mass index) and HbA1c at the 1st booking. This prospective study included 576 patients with GDM. Predictors were prepregnancy BMI, gestational weight gain (GWG), excessive weight gain, fasting, 1 and 2-h glucose values after the 75 g oral glucose challenge test (oGTT), HbA1c at the 1st GDM booking and at the end of pregnancy and maternal treatment requirement. Maternal and neonatal outcomes such as cesarean section, macrosomia, large and small for gestational age (LGA, SGA), neonatal hypoglycemia, prematurity, hospitalization in the neonatal unit and Apgar score at 5 min < 7 were evaluated. Univariate and multivariate regression analyses and probability analyses were performed. One-hour glucose after oGTT and prepregnancy BMI were correlated with cesarean section. GWG and HbA1c at the end pregnancy were associated with macrosomia and LGA, while prepregnancy BMI was inversely associated with SGA. The requirement for maternal treatment was correlated with neonatal hypoglycemia, and HbA1c at the end of pregnancy with prematurity (all p < 0.05). The correlations between predictors and pregnancy complications were exclusively observed when HbA1c was ≥5.5% (37 mmol/mol). In women with prepregnancy BMI ≥ 25 kg/m <sup>2</sup> and HbA1c ≥ 5.5% (37 mmol/mol) at the 1st booking, the risk for cesarean section and LGA was nearly doubled compared to women with BMI with < 25 kg/m <sup>2</sup> and HbA1c < 5.5% (37 mmol/mol). Prepregnancy BMI, GWG, maternal treatment requirement and HbA1c at the end of pregnancy can predict adverse pregnancy outcomes in women with GDM, particularly when HbA1c is ≥5.5% (37 mmol/mol). Stratification based on prepregnancy BMI and HbA1c at the 1st booking may allow for future risk-adapted care in these patients

Outpatient Treatment of Severe Acute Respiratory Syndrome Coronavirus 2 Infection to Prevent Coronavirus Disease 2019 Progression

As of March 2021, coronavirus disease 2019 (COVID-19) had caused more than 123 million infections and almost 3 million deaths worldwide. Dramatic advances have been made in vaccine development and nonpharmaceutical interventions to stop the spread of infection. However, treatments to stop disease progression are limited. A wide variety of "repurposed"drugs evaluated for treatment of COVID-19 have had little or no benefit. More recently, intravenous monoclonal antibody (mAb) combinations have been authorized by the US Food and Drug Administration for emergency use for outpatients with mild to moderate COVID-19 including some active against emerging severe acute respiratory syndrome coronavirus 2 variants of concern. Easier to administer therapeutics including intramuscular and subcutaneous mAbs and oral antivirals are in clinical trials. Reliable, safe, effective COVID-19 treatment for early infection in the outpatient setting is of urgent and critical importance. Availability of such treatment should lead to reduced progression of COVID-19

Shape Space Methods for Quantum Cosmological Triangleland

With toy modelling of conceptual aspects of quantum cosmology and the problem of time in quantum gravity in mind, I study the classical and quantum dynamics of the pure-shape (i.e. scale-free) triangle formed by 3 particles in 2-d. I do so by importing techniques to the triangle model from the corresponding 4 particles in 1-d model, using the fact that both have 2-spheres for shape spaces, though the latter has a trivial realization whilst the former has a more involved Hopf (or Dragt) type realization. I furthermore interpret the ensuing Dragt-type coordinates as shape quantities: a measure of anisoscelesness, the ellipticity of the base and apex's moments of inertia, and a quantity proportional to the area of the triangle. I promote these quantities at the quantum level to operators whose expectation and spread are then useful in understanding the quantum states of the system. Additionally, I tessellate the 2-sphere by its physical interpretation as the shape space of triangles, and then use this as a back-cloth from which to read off the interpretation of dynamical trajectories, potentials and wavefunctions. I include applications to timeless approaches to the problem of time and to the role of uniform states in quantum cosmological modelling.Comment: A shorter version, as per the first stage in the refereeing process, and containing some new reference

Improved lower bounds for the ground-state energy of many-body systems

New lower bounds for the binding energy of a quantum-mechanical system of interacting particles are presented. The new bounds are expressed in terms of two-particle quantities and improve the conventional bounds of the Hall-Post type. They are constructed by considering not only the energy in the two-particle system, but also the structure of the pair wave function. We apply the formal results to various numerical examples, and show that in some cases dramatic improvement over the existing bounds is reached.Comment: 29 pages, 5 figures, to be published in Phys. Rev.

Supersymmetric effects in top quark decay into polarized W-boson

We investigate the one-loop supersymmetric QCD (SUSY-QCD) and electroweak (SUSY-EW) corrections to the top quark decay into a b-quark and a longitudinal or transverse W-boson. The corrections are presented in terms of the longitudinal ratio \Gamma(t-->W_L b)/\Gamma(t--> W b) and the transverse ratio \Gamma(t-->W_- b)/\Gamma(t--> W b). In most of the parameter space, both SUSY-QCD and SUSY-EW corrections to these ratios are found to be less than 1% in magnitude and they tend to have opposite signs. The corrections to the total width \Gamma(t-->W b) are also presented for comparison with the existing results in the literature. We find that our SUSY-EW corrections to the total width differ significantly from previous studies: the previous studies give a large correction of more than 10% in magnitude for a large part of the parameter space while our results reach only few percent at most.Comment: Version in PRD (explanation and refs added

LABORATORY INVESTIGATIONS IN SUPPORT OF FLUID BED FLUORIDE VOLATILITY PROCESSES. PART I. THE FLUORINATION OF URANIUM DIOXIDE-PLUTONIUM DIOXIDE SOLID SOLUTIONS

Work in the development of fluid-bed fluoride volatility processes is described. In these processes, uranium and plutonium in spent nuclear fuels are converted into hexafluoride compounds in a fluid-bed reactor. The uranium and plutonium hexafluorides are volatile and can be separated from fission products, cladding, and alloying materials by techniques such as vaporization and distillation. The experimental work was directed toward devising a fluorination procedure for uranium and plutonium dioxides which would result in a high degree of removal of uranium and plutonium as hexafluorides. In these experiments synthetic mixtures made up to simulate a charge for a fluidized bed reactor (100 kg U, 0.4 kg Pu, approximates 1 kg F.P., and 30 kg inert solids) were used. High-purity recrystallized alumina was found to be a suitable material for use as the fluidized inert solid. After a 10-hr fluorination period at 450 deg C, the concentrations of residual uranium and plutonium on the alumina were 0.01 and 0.03 wt%, respectively. A reaction temperature of 450 deg C was found to be optimum, since experiments at 500 and 550 deg C resulted in plutonium retentions on the alumina of 0.060 and 0.090 wt%, respectively. At all these temperatures, the residual uranium content of the residue was less than 0.01 wt%. When fission product element oxides, in quantities that would be expected in a Dresden-type fuel after 100,000 Mwd/ton burnup and 30 days of cooling, were added to the uranium dioxide-plutonium dioxide-- alumina and the mixture was fluorinated at 450 deg C for 10 hr, the concentration of plutonium on the alumina increased to a value of 0.065 U%. Additional recovery of the plutonium retained on the alumina was obtained by either pyrohydrolysis followed by refluorination at 450 deg C for 10 hr, or by refluorination alone at 550 deg C for 10 hr. These procedures reduced the residual plutonium content of the alumina to less than 0.02 wt%. Experiments were also performed to determine the feasibility of using the same batch of alumina as the inert solid for the fluorinations of five batches of the urania--plutonia solid solution. Experiments were performed in which the solid solution of plutonium dioxide in uranium dioxide was oxidized prior to fluorination. The oxidation resulted in a powdered mixture of uranosic oxide and plutonium dioxide. Fluorination of this oxide mixture in alumina resulted in the removal of essentially all of the uranium in a reaction time of 2 hr at 450 deg C when 10 vol% fluorine was used. When this fluorination was followed by a second fluorination period of 5 hr at 550 deg C with 75 vol% fluorine, the plutonium content of the alumina was 0.011 wt%. When both fluorination periods were extended to 10 hr each, the retention of plutonium was 0.007 wt%, which corresponded to a removal of 99.5% of the plutonium contained in the solid mixture. During the first part of the fluorination period, in which the major portion of the uranium is removed from the mixture of uranium dioxide, plutonium dioxide, alumina, and representative fission product element oxides, a low ternperature (450 deg C) and a low concentration of fluorine (10 vol% fluorine in nitrogen) are desirable. However, in order to remove the plutonium efficiently during the last portion of the fluorination period, it is desirable to use a higher temperature (550 deg C) and a higher fluorine content of the gas mixture (75 vol% fluorine in nitrogen). (auth

Vortex dynamics for two-dimensional XY models

Two-dimensional XY models with resistively shunted junction (RSJ) dynamics and time dependent Ginzburg-Landau (TDGL) dynamics are simulated and it is verified that the vortex response is well described by the Minnhagen phenomenology for both types of dynamics. Evidence is presented supporting that the dynamical critical exponent $z$ in the low-temperature phase is given by the scaling prediction (expressed in terms of the Coulomb gas temperature $T^{CG}$ and the vortex renormalization given by the dielectric constant $\tilde\epsilon$) $z=1/\tilde{\epsilon}T^{CG}-2\geq 2$ both for RSJ and TDGL and that the nonlinear IV exponent a is given by a=z+1 in the low-temperature phase. The results are discussed and compared with the results of other recent papers and the importance of the boundary conditions is emphasized.Comment: 21 pages including 15 figures, final versio