Transport, correlations, and chaos in a classical disordered anharmonic chain

We explore transport properties in a disordered nonlinear chain of classical harmonic oscillators and thereby identify a regime exhibiting behavior analogous to that seen in quantum many-body-localized systems. Through extensive numerical simulations of this system connected at its ends to heat baths at different temperatures, we computed the heat current and the temperature profile in the nonequilibrium steady state as a function of system size $N$, disorder strength $\Delta$, and temperature $T$. The conductivity $\kappa_N$, obtained for finite length ($N$) systems, saturates to a value $\kappa_\infty >0$ in the large $N$ limit, for all values of disorder strength $\Delta$ and temperature $T>0$. We show evidence that for any $\Delta>0$ the conductivity goes to zero faster than any power of $T$ in the $(T/\Delta) \to 0$ limit, and find that the form $\kappa_\infty \sim e^{-B |\ln(C \Delta/T)|^3}$ fits our data. This form has earlier been suggested by a theory based on the dynamics of multi-oscillator chaotic islands. The finite-size effect can be $\kappa_N < \kappa_{\infty}$ due to boundary resistance when the bulk conductivity is high (the weak disorder case), or $\kappa_N > \kappa_{\infty}$ due to direct bath-to-bath coupling through bulk localized modes when the bulk is weakly conducting (the strong disorder case). We also present results on equilibrium dynamical correlation functions and on the role of chaos on transport properties. Finally, we explore the differences in the growth and propagation of chaos in the weak and strong chaos regimes by studying the classical version of the Out-of-Time-Ordered-Commutator.Comment: To appear in Phys. Rev.

Observational study of scalpel versus electrocautery for subcutaneous incision in elective gynaecological surgeries

Background: Considering higher rate of postoperative wound complications in Government set up hospitals, this study was an attempt to compare incision time, incisional blood loss, hospital stay, post-operative pain and postoperative wound complications when subcutaneous tissue is opened with either scalpel or electrocautery in elective gynaecological surgeries after keeping all other clinical and surgical variables same i.e. age, BMI, haemoglobin, incision depth and hospital stay.Methods: This was a prospective observational comparative study conducted in one of the tertiary teaching hospital in Western Maharashtra, India over 12 months. All patients (n=100) were divided into 2 groups. Group A in which skin and subcutaneous tissue was dissected by using scalpel and Group B in which after skin, anterior abdominal wall was opened by using electrocautery. Data analyzed for indication, incisional blood loss, incision time, postoperative pain, wound complications and hospital stay.Results: There were no significant association between preoperative diagnosis and the development of a post-operative wound complications. Mean incision blood loss was found to be significantly higher in group A compared to group B patients. Postoperative pain was significantly higher in group A (P value <0.05). Among wound complications, no statistically significant differences were seen regarding wound complications for the two groups.Conclusions: Electrosurgical dissection for abdominal incision is safe, less time consuming and with less blood loss during subcutaneous incision and produces less postoperative pain. We conclude that the method of subcutaneous tissue incision was unrelated to the development of postoperative abdominal incision problems

Synthesizing Attack-Aware Control and Active Sensing Strategies under Reactive Sensor Attacks

We consider the probabilistic planning problem for a defender (P1) who can jointly query the sensors and take control actions to reach a set of goal states while being aware of possible sensor attacks by an adversary (P2) who has perfect observations. To synthesize a provably correct, attack-aware control and active sensing strategy for P1, we construct a stochastic game on graph where the augmented state includes the actual game state (known by the attacker), the belief of the defender about the game state (constructed by the attacker given the attacker's information about the defender's information). We presented an algorithm to solve a belief-based, randomized strategy for P1 to ensure satisfying P1's reachability objective with probability one, under the worst case sensor attacks carried out by an informed P2. The correctness of the algorithm is proven and illustrated with an example.Comment: 6 pages, 1 figure, 1 table, 1 algorith

Unusual ergodic and chaotic properties of trapped hard rods

We investigate ergodicity, chaos and thermalization for a one-dimensional classical gas of hard rods confined to an external quadratic or quartic trap, which breaks microscopic integrability. To quantify the strength of chaos in this system, we compute its maximal Lyapunov exponent numerically. The approach to thermal equilibrium is studied by considering the time evolution of particle position and velocity distributions and comparing the late-time profiles with the Gibbs state. Remarkably, we find that quadratically trapped hard rods are highly non-ergodic and do not resemble a Gibbs state even at extremely long times, despite compelling evidence of chaos for four or more rods. On the other hand, our numerical results reveal that hard rods in a quartic trap exhibit both chaos and thermalization, and equilibrate to a Gibbs state as expected for a nonintegrable many-body system.Comment: 10 pages, 10 figure

Generation, annotation, and analysis of ESTs from midgut tissue of adult female Anopheles stephensi mosquitoes

<p>Abstract</p> <p>Background</p> <p>Malaria is a tropical disease caused by protozoan parasite, <it>Plasmodium</it>, which is transmitted to humans by various species of female anopheline mosquitoes. <it>Anopheles stephensi </it>is one such major malaria vector in urban parts of the Indian subcontinent. Unlike <it>Anopheles gambiae</it>, an African malaria vector, transcriptome of <it>A. stephensi </it>midgut tissue is less explored. We have therefore carried out generation, annotation, and analysis of expressed sequence tags from sugar-fed and <it>Plasmodium yoelii </it>infected blood-fed (post 24 h) adult female <it>A. stephensi </it>midgut tissue.</p> <p>Results</p> <p>We obtained 7061 and 8306 ESTs from the sugar-fed and <it>P. yoelii </it>infected mosquito midgut tissue libraries, respectively. ESTs from the combined dataset formed 1319 contigs and 2627 singlets, totaling to 3946 unique transcripts. Putative functions were assigned to 1615 (40.9%) transcripts using BLASTX against UniProtKB database. Amongst unannotated transcripts, we identified 1513 putative novel transcripts and 818 potential untranslated regions (UTRs). Statistical comparison of annotated and unannotated ESTs from the two libraries identified 119 differentially regulated genes. Out of 3946 unique transcripts, only 1387 transcripts were mapped on the <it>A. gambiae </it>genome. These also included 189 novel transcripts, which were mapped to the unannotated regions of the genome. The EST data is available as ESTDB at <url>http://mycompdb.bioinfo-portal.cdac.in/cgi-bin/est/index.cgi</url>.</p> <p>Conclusion</p> <p>3946 unique transcripts were successfully identified from the adult female <it>A. stephensi </it>midgut tissue. These data can be used for microarray development for better understanding of vector-parasite relationship and to study differences or similarities with other malaria vectors. Mapping of putative novel transcripts from <it>A. stephensi </it>on the <it>A. gambiae </it>genome proved fruitful in identification and annotation of several genes. Failure of some novel transcripts to map on the <it>A. gambiae </it>genome indicates existence of substantial genomic dissimilarities between these two potent malaria vectors.</p

12-Lipoxygenase governs the innate immune pathogenesis of islet inflammation and autoimmune diabetes

Macrophages and related myeloid cells are innate immune cells that participate in the early islet inflammation of type 1 diabetes (T1D). The enzyme 12-lipoxygenase (12-LOX) catalyzes the formation of proinflammatory eicosanoids, but its role and mechanisms in myeloid cells in the pathogenesis of islet inflammation have not been elucidated. Leveraging a model of islet inflammation in zebrafish, we show here that macrophages contribute significantly to the loss of β cells and the subsequent development of hyperglycemia. The depletion or inhibition of 12-LOX in this model resulted in reduced macrophage infiltration into islets and the preservation of β cell mass. In NOD mice, the deletion of the gene encoding 12-LOX in the myeloid lineage resulted in reduced insulitis with reductions in proinflammatory macrophages, a suppressed T cell response, preserved β cell mass, and almost complete protection from the development of T1D. 12-LOX depletion caused a defect in myeloid cell migration, a function required for immune surveillance and tissue injury responses. This effect on migration resulted from the loss of the chemokine receptor CXCR3. Transgenic expression of the gene encoding CXCR3 rescued the migratory defect in zebrafish 12-LOX morphants. Taken together, our results reveal a formative role for innate immune cells in the early pathogenesis of T1D and identify 12-LOX as an enzyme required to promote their prodiabetogenic phenotype in the context of autoimmunity