Random polytopes obtained by matrices with heavy tailed entries

Let $\Gamma$ be an $N\times n$ random matrix with independent entries and such that in each row entries are i.i.d. Assume also that the entries are symmetric, have unit variances, and satisfy a small ball probabilistic estimate uniformly. We investigate properties of the corresponding random polytope $\Gamma^* B_1^N$ in $\mathbb{R}$ (the absolute convex hull of rows of $\Gamma$). In particular, we show that $$\Gamma B_1^N \supset b^{-1} \left( B_{\infty}^n \cap \sqrt{\ln (N/n)}\, B_2^n \right).$$ where $b$ depends only on parameters in small ball inequality. This extends results of \cite{LPRT} and recent results of \cite{KKR}. This inclusion is equivalent to so-called $\ell_1$-quotient property and plays an important role in compressive sensing (see \cite{KKR} and references therein).Comment: Last version, to appear in Communications in Contemporary Mathematic

Random polytopes obtained by matrices with heavy tailed entries

Let $\Gamma$ be an $N\times n$ random matrix with independent entries and such that in each row entries are i.i.d. Assume also that the entries are symmetric, have unit variances, and satisfy a small ball probabilistic estimate uniformly. We investigate properties of the corresponding random polytope $\Gamma^* B_1^N$ in $\mathbb{R}$ (the absolute convex hull of rows of $\Gamma$). In particular, we show that $$\Gamma B_1^N \supset b^{-1} \left( B_{\infty}^n \cap \sqrt{\ln (N/n)}\, B_2^n \right).$$ where $b$ depends only on parameters in small ball inequality. This extends results of \cite{LPRT} and recent results of \cite{KKR}. This inclusion is equivalent to so-called $\ell_1$-quotient property and plays an important role in compressive sensing (see \cite{KKR} and references therein).Comment: Last version, to appear in Communications in Contemporary Mathematic

Biodegradation of Congo Red by Phanerochaete chrysosporium

The azo dye Congo Red, was degraded extensively by the wood rotting basidiomycete, Phanerochaete chrysosporium in agitated liquid cultures and in solid malt agar cultures. Upon addition of Congo Red to agitated liquid cultures, the dye was adsorbed to the mycelial pellets in both ligninolytic and non-ligninolytic cultures followed by extensive degradation only in the ligninolytic cultures. This fungus, grown from conidiospores, readily degraded up to 718 μM (500 mg/l) Congo Red in 2.0% malt agar. Decolorization of Congo Red in malt agar plates was suppressed by the addition of supplemental nutrient nitrogen indicating that the lignin degrading system of P. chrysosporium may be important in the biodegradation of this dye. This is supported by the observation that Congo Red is a substrate for purified lignin peroxidase H8. These results are of interest because it had been previously reported that Congo Red was not a substrate for lignin peroxidase nor was it extensively degraded by this fungus

Optimization of cytochrome c detection by acoustic and electrochemical methods based on aptamer sensors

© 2016 Elsevier B.V.We report the effect of various factors such as oligonucleotide sequence, buffer composition, ionic strength for optimal determination of cytochrome c (cyt c) by DNA aptamer sensors using thickness shear mode acoustics (TSM) and electrochemical methods. Up to now, several DNA aptamers specific to cyt c have been selected and used in various sensing approaches including optical, electrochemical and mass sensitive transducers. We have analyzed the response of three different aptamers immobilized via biotin-neutravidin method on a gold support by TSM technique. Using this approach we have shown that only 76-length base sequence (apt 76) exhibited specific binding to cyt c with detection limit of 0.50 ± 0.05 nM. This aptamer was then studied under different ionic conditions showing an optimal response for HEPES buffer. Apt 76 based sensor has been also examined by electrochemical methods. However due to the electroactive nature of cyt c, the response of this aptamer was less favorable in comparison with TSM. The apt 76 based sensor was tested also in spiked samples of human plasma by TSM achieving a recovery of 92 ± 6.6% for 1 nM cyt c

Design, Realization, and Characterization of Advanced Adhesives for Joining Ultra-Stable C/C Based Components

The aim of this work is to develop high-performance adhesives to join carbon fiber reinforced composites (C/C) for use in aerospace applications; in order to guarantee sound mechanical strength, a low coefficient of thermal expansion, and ease of application on large components. Several different adhesive formulations, based on phenolic or cyanate-ester resins (charged with the maximum experimentally feasible amount of carbon-based fillers), are developed and tested. The measurements of the lap shear strength at room temperature of the C/C joined by means of one phenolic and one cyanate ester-based resin demonstrates that these formulations are the most suitable for the given application. A complete characterization, by means of viscosimetry, dilatometry, and thermal gravimetric analysis, coupled with gas analysis by means of mass spectroscopy, confirms that the phenolic-based formulation is the most promising joining material. A nano-indenter is used to obtain its Young modulus and hardness, both inside the joint and as a bulk cured adhesive

A clarion call for aeolian research to engage with global land degradation and climate change

This editorial represents a clarion call for the aeolian research community to provide increased scientific input to the Intergovernmental Panel on Climate Change (IPCC) and the United Nations Convention to Combat Desertification (UNCCD) and an invitation to apply for ISAR funding to organize a working group to support this engagement

Enhancing wind erosion monitoring and assessment for U.S. rangelands

Wind erosion is a major resource concern for rangeland managers because it can impact soil health, ecosystem structure and function, hydrologic processes, agricultural production, and air quality. Despite its significance, little is known about which landscapes are eroding, by how much, and when. The National Wind Erosion Research Network was established in 2014 to develop tools for monitoring and assessing wind erosion and dust emissions across the United States. The Network, currently consisting of 13 sites, creates opportunities to enhance existing rangeland soil, vegetation, and air quality monitoring programs. Decision-support tools developed by the Network will improve the prediction and management of wind erosion across rangeland ecosystems. © 2017 The Author(s)The Rangelands archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information

U.S. Billion-ton Update: Biomass Supply for a Bioenergy and Bioproducts Industry

The Report, Biomass as Feedstock for a Bioenergy and Bioproducts Industry: The Technical Feasibility of a Billion-Ton Annual Supply (generally referred to as the Billion-Ton Study or 2005 BTS), was an estimate of “potential” biomass within the contiguous United States based on numerous assumptions about current and future inventory and production capacity, availability, and technology. In the 2005 BTS, a strategic analysis was undertaken to determine if U.S. agriculture and forest resources have the capability to potentially produce at least one billion dry tons of biomass annually, in a sustainable manner—enough to displace approximately 30% of the country’s present petroleum consumption. To ensure reasonable confidence in the study results, an effort was made to use relatively conservative assumptions. However, for both agriculture and forestry, the resource potential was not restricted by price. That is, all identified biomass was potentially available, even though some potential feedstock would more than likely be too expensive to actually be economically available. In addition to updating the 2005 study, this report attempts to address a number of its shortcoming

What makes young Russians happy and satisfied with their lives?

Participants (N = 10,672 with the mean age of 20.7 years) of the Russian Character and Personality Survey (RCPS), involving 40 universities or colleges from across the Russian Federation, rated their happiness and satisfaction with life; the ratings were combined into an index of subjective well-being (SWB). Using the National Character Survey (NCS), participants also rated their own personality characteristics as well as those of an ideal person and a typical Russian living in their own region. Only two personality (test) subscales—N3: Depression and E6: Positive Emotions—were correlated with SWB on the between-individual level of analysis. Although spiritual values associated with a negative attitude toward money are typically regarded as an essential part of the Russian national character, our results demonstrated that only satisfaction with one’s own financial situation was a reliable predictor of SWB. In those regions where people had, on average, a higher life expectancy, better education, and a higher level of wealth, individuals also tended to be happier and more satisfied with their lives

Individual and culture-level components of survey response styles: a multi-level analysis using cultural models of selfhood

Variations in acquiescence and extremity pose substantial threats to the validity of cross-cultural research that relies on survey methods. Individual and cultural correlates of response styles when using two contrasting types of response mode were investigated, drawing on data from 55 cultural groups across 33 nations. Using seven dimensions of self-other relatedness that have often been confounded within the broader distinction between independence and interdependence, our analysis yields more specific understandings of both individual- and culture-level variations in response style. When using a Likert scale response format, acquiescence is strongest among individuals seeing themselves as similar to others, and where cultural models of selfhood favour harmony, similarity with others and receptiveness to influence. However, when using Schwartz’s (2007) portrait-comparison response procedure, acquiescence is strongest among individuals seeing themselves as self-reliant but also connected to others, and where cultural models of selfhood favour self-reliance and self-consistency. Extreme responding varies less between the two types of response modes, and is most prevalent among individuals seeing themselves as self-reliant, and in cultures favouring self-reliance. Since both types of response mode elicit distinctive styles of response, it remains important to estimate and control for style effects to ensure valid comparisons