Two-sided estimates of minimum-error distinguishability of mixed quantum states via generalized Holevo-Curlander bounds

We prove a concise factor-of-2 estimate for the failure rate of optimally distinguishing an arbitrary ensemble of mixed quantum states, generalizing work of Holevo [Theor. Probab. Appl. 23, 411 (1978)] and Curlander [Ph.D. Thesis, MIT, 1979]. A modification to the minimal principle of Cocha and Poor [Proceedings of the 6th International Conference on Quantum Communication, Measurement, and Computing (Rinton, Princeton, NJ, 2003)] is used to derive a suboptimal measurement which has an error rate within a factor of 2 of the optimal by construction. This measurement is quadratically weighted and has appeared as the first iterate of a sequence of measurements proposed by Jezek et al. [Phys. Rev. A 65, 060301 (2002)]. Unlike the so-called pretty good measurement, it coincides with Holevo's asymptotically optimal measurement in the case of nonequiprobable pure states. A quadratically weighted version of the measurement bound by Barnum and Knill [J. Math. Phys. 43, 2097 (2002)] is proven. Bounds on the distinguishability of syndromes in the sense of Schumacher and Westmoreland [Phys. Rev. A 56, 131 (1997)] appear as a corollary. An appendix relates our bounds to the trace-Jensen inequality.Comment: It was not realized at the time of publication that the lower bound of Theorem 10 has a simple generalization using matrix monotonicity (See [J. Math. Phys. 50, 062102]). Furthermore, this generalization is a trivial variation of a previously-obtained bound of Ogawa and Nagaoka [IEEE Trans. Inf. Theory 45, 2486-2489 (1999)], which had been overlooked by the autho

Wrinkling of a bilayer membrane

The buckling of elastic bodies is a common phenomenon in the mechanics of solids. Wrinkling of membranes can often be interpreted as buckling under constraints that prohibit large amplitude deformation. We present a combination of analytic calculations, experiments, and simulations to understand wrinkling patterns generated in a bilayer membrane. The model membrane is composed of a flexible spherical shell that is under tension and that is circumscribed by a stiff, essentially incompressible strip with bending modulus B. When the tension is reduced sufficiently to a value \sigma, the strip forms wrinkles with a uniform wavelength found theoretically and experimentally to be \lambda = 2\pi(B/\sigma)^{1/3}. Defects in this pattern appear for rapid changes in tension. Comparison between experiment and simulation further shows that, with larger reduction of tension, a second generation of wrinkles with longer wavelength appears only when B is sufficiently small.Comment: 9 pages, 5 color figure

Building a Freshwater Bacterial Flora Database for Remote Sensing Applications

The identification and classification of microbial flora in bodies of fresh water has the potential of enhancing our understanding of this ecosystem and improving water management and bioremediation. This effort may be facilitated by the use of remote sensing technologies. For the last 3 years our undergraduate students have collected water samples in the Lake Ontario Rochester Embayment and Irondequoit Bay with the goal of constructing a database of bacterial species and water parameters (e.g. organic matter and chlorophyl content). Such a database is necessary to establish potential correlations between the presence of certain bacterial species and water parameters that can be measured using satellite imagery collected by the Landsat 8 OLI and TIRS sensors. In the past we reported initial efforts at mapping the distribution of bacterial species using 16S rRNA. Here we present our results for the summer of 2015 and present a compounded analysis of 3 consecutive summers. Of approximately 450 bacterial isolates, we have cultured and identified more than 40 different species spanning over 20 genera. Several fish and human pathogens were identified, and antibiotic-resistance profiles determined. Year to year variation of the flora’s composition at individual locations has emerged as the main challenge in establishing reproducible patterns that may be linked to satellite measurements

Microbial Sampling of Major Bodies of Water in Rochester, NY

Public health concerns from wastewater treatment and agricultural runoff are an issue locally in Rochester, NewYork. In fact, many closings of Ontario Beach have been attributed to pollution or the threat of microbial contamination. Antibiotic resistance is a major issue that has become more prevalent in society, antibiotic resistant human pathogenic bacteria can overcome normal types of medicinal therapy, which cannot only lead to increased mortality but also increases in illness and cost of care. Additionally, antibiotic resistant plant pathogens can impact agriculture. In this study, bacterial species from the Lake Ontario embayment collected over the past three years were analyzed. Bacteria that were known to be human or plant pathogens were selected to evaluate for resistance to commonly used antibiotics using the Kirby Bauer disk diffusion assay. A few species exhibited resistance, preliminary results will be shown

Remote Sensing of Freshwater Bacterial Populations Using Spectral Analysis of Satellite Imagery

Remote sensing of bacterial populations in small and large bodies of water can significantly enhance our ability to understand fresh water ecosystems and monitor water quality. Although the identification of individual species is still unfeasible, the detection of certain bacterial groups and the likelihood of occurrence would be very valuable. Spectral analysis of satellite imagery is currently used to determine water parameters like temperature, turbidity, phytoplankton and dissolved organic matter. In order to establish a correlation between some of these parameters and the presence of microorganisms, we collected water samples from several locations in the Lake Ontario Rochester Embayment and Irondequoit Bay that were imaged by the new Landsat 8 OLI and TIRS sensors. Using bacterial 16S rRNA, we mapped the diversity and distribution of microorganisms isolated from the samples and then linked this information to the bio-optical properties of the water. Our results represent an early attempt to develop a method for the remote detection of bacteria. A comprehensive understanding of the factors affecting the conditions favoring the establishment of the various colonies will require a library of seasonal ground truth sampling and remote sensing observations to assess potential probability and geographic distributions of the bacterial populations

Evaluation of Plant-Based Byproducts as Green Fining Agents for Precision Winemaking

Consumers are increasingly looking for foods, including wine, that are free of animal-derived proteins. This study seeks to evaluate patatin, a new, plant-based and allergen-free fining agent, by comparing it with the fining agents polyvinipolypyrrolidone, bovine serum albumin, and methylcellulose. Specifically, its effects on the phenolic profile of enological tannins were analyzed with four spectrophotometric assays: OD 280 nm, Folin–Ciocâlteu, Adams–Harbertson, and methylcellulose. In addition, changes in the polyphenol composition of Sangiovese red wine were determined by UV-Vis spectrophotometry and HPLC with adsorption trials, and the solid–liquid interaction in a wine solution was modeled by both Langmuir and Freundlich equations. Our findings highlight the occurrence of systematic proportional error between the selected spectrophotometric assays. As a result, direct comparisons of protein precipitation assays can be made only among results obtained with the same spectrophotometric method. However, it is clear that patatin has an impact on the phenolic profile of Sangiovese red wine: it removes simple phenolics (gallic acid, (+)-catechin, (–)-epicatechin, epicatechin gallate, syringic acid, fertaric acid, coutaric acid, and rutin) as well as both oligomeric and polymeric tannins to different extents. In concentrations of less than 1 g/L, the patatin isotherm showed a linear relation between the equilibrium concentration and the quantity absorbed, obeying the Freundlich model reasonably well (KF 1.46; 1/n 1.07; R2 0.996 with 1/n > 1). Thus, the adsorption process is strongly dependent on the fining dosage

Multi-Year Analysis of Microbial Populations in the Rochester-Lake Ontario Embayment

The composition of freshwater bacterial populations is affected by a wide variety of factors. Temperature, acidity, organic matter, and environmental pollutants like industrial chemicals and antibiotics are a few examples. The impact that bodies of freshwater have on human activity and the wider ecosystem warrants the systematic identification of microbial flora, and in particular of species known to be pathogenic in plants and animals. In order to achieve the long term goal of using satellite imagery to predict the occurrence of specific bacterial species, our team is in the process of creating a multi-location, multi-year microbial flora database for the Rochester Lake Ontario embayment and nearby bodies of water. Our collaborators at the Rochester Institute of Technology have provided us with water samples collected at these locations during the summers of 2013 and 2014. In this work we present and analyze data from said samples. Using 16S ribosomal DNA data we characterize bacterial populations, determine their geographical distribution, establish genera prevalence and discuss the presence of and investigate antibiotic resistance in several pathogenic species. The scope of our long term project and the summer of 2015- sample collection are also considered