Asymptotic analysis of the Anderson parabolic problem and the Moser's type optimal stopping problem

The central objects of the thesis are the Anderson parabolic problem and the Moser’s type optimal stopping problem: (1) In the lattice parabolic Anderson problem, we study the quenched and annealed asymptotics for the solutions of the lattice parabolic Anderson equation in the situa- tion in which the underlying random walk has long jumps and belongs to the domain of attraction of the stable process. The i.i.d random potential in our case is unbounded from above with regular Weibull type tails. Similar models but with the local basic Hamiltonian (lattice Laplacian) were analyzed in the very first work on intermittency for the parabolic Anderson problem by J. Ga ¨rtner and S. Molchanov. We will show that the long range model demonstrates the new effect. The annealed (moment) and quenched (almost sure) asymptotics of the solution have the same order in contrast to the case of the local models for which these orders are essentially different. (2) Concerning Moser’s problem, we study two related optimization problems for i.i.d. random variables Xi, i = 1, 2, ..., n, referred to as the generalized Moser’s problem: a) Find maxt=n EXt (t = n are the stopping times). b) Find t: P{Xt = Mn}=max, here Mn = max0=i=n Xi. For the wide class of continuous distribution functions FX(x) with regular tails, we will present the asymptotic formulas for the optimal thresholds and analyze the relationship between the Moser’s type problem and the classical secretary problem with information. The present paper is structured as follows: The first two chapters contain preliminary information. In Chapter 1, we summarize some important properties and results about slowly varying functions. In Chapter 2, we introduce the Anderson parabolic model, summarize some main results, such as the uniqueness and existence and the asymptotic properties of of the solution u(t,x), for the parabolic Anderson model on Zd and Rd with homogenous potentials, and discuss some limit theorems for random walks with heavy-tailed long jumps. In Chapter 3, we prove several results on the annealed and quenched behavior of u(t, x) as t ? 8 with Weibull’s potential. We will show that the long range model demonstrates the new effect. The annealed (moment) and quenched (almost sure) asymptotics of the solution have the same order in contrast to the case of the local models for which these orders are essentially different. In Chapter 4, we study Moser’s problem, present the asymptotic formulas for the optimal thresholds of the wide class of continuous distribution functions FX (x) with regular tails, and analyze the relationship between the Moser’s type problem and the classical secretary problem with information

Exploring the influence of exercise timing relative to exposure to a memory task on long-term recall

Physical activity is beneficial to cognitive function, including memory which is an essential function we use in our daily life. Roig, Nordbrandt, Geertsen, and Nielsen (2013) meta-analysis provides evidence that a single bout of exercise has positive effects on short-term/working and long-term memory. Additionally, the majority of studies showed that compared to a no-treatment control condition, improved memory task performance was reported when an acute bout of exercise occurred prior to memory tasks. However, only two studies have specifically investigated the influence of exercise timing relative to exposure to the memory task on memory performance (Labban & Etnier, 2011; Salas, Minakata, & Kelemen, 2011). In order to expand the literature, the current study examined the effects of the timing of exercise relative to a memory task on long-term recall performance by assigning participants into one of four experimental conditions: 1) exercise before memory exposure, 2) exercise after memory exposure, 3) exercise before long-term recall, and 4) no-exercise control condition. Eight-three participants completed the study. Results showed that no differences among treatment groups reached statistical significance on all memory measures. These findings indicated that a single, short bout of exercise at different points relative to memory exposure neither benefit nor hinder memory task performance. Future research exploring how exercise intensity and duration interact to influence memory performance is needed

Can't go home

This thesis is a compilation of short stories around the theme of home. The characters struggle with how home shapes their values and desires. They seek to reconcile where they've come from with who they presently are and who they wish to become. Most of the characters are looking for a place to belong

Route to high-energy density polymeric nitrogen t-N via He-N compounds.

Polymeric nitrogen, stabilized by compressing pure molecular nitrogen, has yet to be recovered to ambient conditions, precluding its application as a high-energy density material. Here we suggest a route for synthesis of a tetragonal polymeric nitrogen, denoted t-N, via He-N compounds at high pressures. Using first-principles calculations with structure searching, we predict a class of nitrides with stoichiometry HeN4 that are energetically stable (relative to a mixture of solid He and N2) above 8.5 GPa. At high pressure, HeN4 comprises a polymeric channel-like nitrogen framework filled with linearly arranged helium atoms. The nitrogen framework persists to ambient pressure on decompression after removal of helium, forming pure polymeric nitrogen, t-N. t-N is dynamically and mechanically stable at ambient pressure with an estimated energy density of ~11.31 kJ/g, marking it out as a remarkable high-energy density material. This expands the known polymeric forms of nitrogen and indicates a route to its synthesis

Osteomyelitis Infection of Mycobacterium marinum: A Case Report and Literature Review

Mycobacterium marinum (M. marinum) is a ubiquitous waterborne organism that grows optimally at temperatures around 30°C. It is a nontuberculous Mycobacterium found in nonchlorinated water with worldwide prevalence. It is the most common atypical Mycobacterium that causes opportunistic infection in humans. M. marinum can cause superficial infections and localized invasive infections in humans, with the hands being the sites most frequently affected. It can cause skin lesions, which are either single, papulonodular lesions, confined to an extremity, or may resemble cutaneous sporotrichosis. This infection can also cause deeper infections including tenosynovitis, bursitis, arthritis, and osteomyelitis. Disseminated infections and visceral involvements have been reported in immunocompromised patients. We here report a case of severe deep soft tissue infection with necrotizing fasciitis and osteomyelitis of the left upper extremity (LUE) caused by M. marinum in an immunocompromised patient.Open Access Publishing Support Fun

On the Application of Vickers Micro Hardness Testing to Isotactic Polypropylene

Hardness is a useful measure of a material’s resistance to permanent indentation; but for viscoelastic polymers, hardness data are highly dependent on the test type and the parameter set chosen. Vickers microhardness testing is used to leave small indents (<150 µm) and is shown to be applicable to polymers. A detailed investigation of the required steps for microhardness testing in isotactic polypropylene (iPP) is provided. Samples should be mounted in epoxy resin in order to maintain curing temperatures at room temperature. Mounted samples can be ground and polished in a semi-automatic polisher using graduated SiC paper (wet grinding) but progressing onto alumina suspension for polishing. Final polishing should be performed with 0.05-µm alumina suspension. The hardness measured was shown to be dependent on load and dwell time with a much greater dependency on dwell time. Strain recovery was shown to be completed after a time period equal to the dwell time. This study shows that indents can be measured thereafter, and it is recommended that they be measured within a 24 h period after the indent was created. After data fitting, the equation for hardness was shown to follow a power law with load and dwell time as the main variables. Fitting parameters were compared to those found in the literature, and it was found that parameters were significantly different to those reported elsewhere. Therefore, this study highlights the importance of calibrating on a case-by-case basis. Finally, to show the usefulness of the Vickers micro-hardness testing method, the calibrated test method was applied on iPP with additions of carbon black up to 3 wt.%. Comparisons were made with data from the literature, but the hardness data generated in our work were found to be at least twice that reported in the literature. The testing parameters were not cited in the literature: specifically, the dwell time was not provided, and this generated doubt on the usefulness of the cited data. Hence, this work is intended to serve as an exemplar of how to prepare and proceed with hardness testing of polymers

Cap-Independent Translation Promotes C. elegans Germ Cell Apoptosis through Apaf-1/CED-4 in a Caspase-Dependent Mechanism

Apoptosis is a natural process during animal development for the programmed removal of superfluous cells. During apoptosis general protein synthesis is reduced, but the synthesis of cell death proteins is enhanced. Selective translation has been attributed to modification of the protein synthesis machinery to disrupt cap-dependent mRNA translation and induce a cap-independent mechanism. We have previously shown that disruption of the balance between cap-dependent and cap-independent C. elegans eIF4G isoforms (IFG-1 p170 and p130) by RNA interference promotes apoptosis in developing oocytes. Germ cell apoptosis was accompanied by the appearance of the Apaf-1 homolog, CED-4. Here we show that IFG-1 p170 is a native substrate of the worm executioner caspase, CED-3, just as mammalian eIF4GI is cleaved by caspase-3. Loss of Bcl-2 function (ced-9ts) in worms induced p170 cleavage in vivo, coincident with extensive germ cell apoptosis. Truncation of IFG-1 occurred at a single site that separates the cap-binding and ribosome-associated domains. Site-directed mutagenesis indicated that CED-3 processes IFG-1 at a non-canonical motif, TTTD456. Coincidentally, the recognition site was located 65 amino acids downstream of the newly mapped IFG-1 p130 start site suggesting that both forms support cap-independent initiation. Genetic evidence confirmed that apoptosis induced by loss of ifg-1 p170 mRNA was caspase (ced-3) and apoptosome (ced-4/Apaf-1) dependent. These findings support a new paradigm in which modal changes in protein synthesis act as a physiological signal to initiate cell death, rather than occur merely as downstream consequences of the apoptotic event

Validated outcome of treatment changes according to International League Against Epilepsy criteria in adults with drug-resistant focal epilepsy.

OBJECTIVE: Although many studies have attempted to describe treatment outcomes in patients with drug-resistant epilepsy, results are often limited by the adoption of nonhomogeneous criteria and different definitions of seizure freedom. We sought to evaluate treatment outcomes with a newly administered antiepileptic drug (AED) in a large population of adults with drug-resistant focal epilepsy according to the International League Against Epilepsy (ILAE) outcome criteria. METHODS: This is a multicenter, observational, prospective study of 1053 patients with focal epilepsy diagnosed as drug-resistant by the investigators. Patients were assessed at baseline and 6, 12, and 18 months, for up to a maximum of 34 months after introducing another AED into their treatment regimen. Drug resistance status and treatment outcomes were rated according to ILAE criteria by the investigators and by at least two independent members of an external expert panel (EP). RESULTS: A seizure-free outcome after a newly administered AED according to ILAE criteria ranged from 11.8% after two failed drugs to 2.6% for more than six failures. Significantly fewer patients were rated by the EP as having a "treatment failure" as compared to the judgment of the investigator (46.7% vs 62.9%, P < 0.001), because many more patients were rated as "undetermined outcome" (45.6% vs 27.7%, P < 0.001); 19.3% of the recruited patients were not considered drug-resistant by the EP. SIGNIFICANCE: This study validates the use of ILAE treatment outcome criteria in a real-life setting, providing validated estimates of seizure freedom in patients with drug-resistant focal epilepsy in relation to the number of previously failed AEDs. Fewer than one in 10 patients achieved seizure freedom on a newly introduced AED over the study period. Pseudo drug resistance could be identified in one of five cases

Probing ferroelectricity by X-ray absorption spectroscopy in molecular crystals

We carry out X-ray absorption spectroscopy experiment at the oxygen K edge in croconic acid (C5H2O5) crystal as a prototype of ferroelectric organic molecular solid, whose electric polarization is generated by proton transfer. The experimental spectrum is well reproduced by the electron-hole excitation theory simulations from configuration generated by ab initio molecular dynamics simulation. When inversion symmetry is broken in the ferroelectric state, the hydrogen bonding environment on the two bonded molecules become inequivalent. Such a difference is sensitively probed by the bound excitation in the pre-edge, which is strongly localized on the excited molecules. Our analysis shows that a satellite peak in the pre-edge will emerge at higher excitation energy, which serves as a clear signature of ferroelectricity in the material

Imperial trophy or island relict? A new extinction paradigm for Père David's deer: a Chinese conservation icon

The file attached is the Published/publisher’s pdf version of the article