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BackgroundDecubitus ulcers, also known as bedsores or pressure ulcers, affect millions of hospitalized patients each year. The microflora of chronic wounds such as ulcers most commonly exist in the biofilm phenotype and have been known to significantly impair normal healing trajectories.MethodsBacterial tag-encoded FLX amplicon pyrosequencing (bTEFAP), a universal bacterial identification method, was used to identify bacterial populations in 49 decubitus ulcers. Diversity estimators were utilized and wound community compositions analyzed in relation to metadata such as Age, race, gender, and comorbidities.ResultsDecubitus ulcers are shown to be polymicrobial in nature with no single bacterium exclusively colonizing the wounds. The microbial community among such ulcers is highly variable. While there are between 3 and 10 primary populations in each wound there can be hundreds of different species present many of which are in trace amounts. There is no clearly significant differences in the microbial ecology of decubitus ulcer in relation to metadata except when considering diabetes. The microbial populations and composition in the decubitus ulcers of diabetics may be significantly different from the communities in non-diabetics.ConclusionsBased upon the continued elucidation of chronic wound bioburdens as polymicrobial infections, it is recommended that, in addition to traditional biofilm-based wound care strategies, an antimicrobial/antibiofilm treatment program can be tailored to each patient's respective wound microflora.

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We probe the presence of long-range correlations in phase fluctuations by analyzing the higherorder spectrum of resistance fluctuations in ultra-thin NbN superconducting films. The nonGaussian component of resistance fluctuations is found to be sensitive to film thickness close to the transition, which allows us to distinguish between mean field and Berezinskii-Kosterlitz-Thouless (BKT) type superconducting transitions. The extent of non-Gaussianity was found to be bounded by the BKT and mean field transition temperatures and depend strongly on the roughness and structural inhomogeneity of the superconducting films. Our experiment outlines a novel fluctuation-based kinetic probe in detecting the nature of superconductivity in disordered low-dimensional materials.The transition from superconducting to normal state in two-dimensions is known to occur via BerezinskiiKosterlitz-Thouless (BKT) mechanism. Traditionally, the signature of BKT transition is found by measuring the superfluid density where a discontinuity is observed at the critical temperature T BKT [1][2][3]. This method is limited in its scope of application for systems exhibiting interfacial/buried superconductivity like oxide heterostructures due to the inability to measure the thickness of the superconducting layer accurately. Transport-based probes including discontinuity in the power law behavior of I-V characteristics or change in the curvature of magnetoresistance from convex to concave in the presence of a perpendicular magnetic field [4][5][6][7][8][9] have their limitations as real systems contain some degree of inhomogeneity which smear out the signatures of BKT type behavior. With growing interest in lowdimensional superconductivity, it is interesting to develop new probes/techniques that are not only sensitive enough to detect BKT transition but also compare its characteristics scales with the mean field description.The BKT transition, as exhibited by ultra-thin superconducting films, is characterized by the unbinding of vortex pairs beyond T BKT . It is well known that these vortices exhibit long-range interactions which vary logarithmically with the distance between the vortices. Vortices also occur in bulk Type-II superconductors in the presence of an external magnetic field. Earlier experiments probing vortices in bulk films through measurements of flux flow noise and voltage noise have reported the presence of broad band noise (BBN) [10,11] as a function of driving current and magnetic field. The statistics of noise in these systems is non-Gaussian due to the fact that most of the noise arise from very few fluctuators. Noise measurements on quasi-2D MgB 2 films show a possibility of thermally induced vortex hopping through measurements of flux noise close to BKT transition [12]. To the best of our knowledge there are no reports on higher-order statistics of fluctuations looking into the possibility of interacting vortices in two-dimensions.Higher-order fluctuations in resistivity has been established as an useful tool to study the pres...