Sequence distribution studies of dichloroprotoanemonin-methyl methacrylate copolymers

Chloride elimination and ultraviolet bands in dichloroprotoanemonin/methyl methacrylate copolymer

Simultaneous extreme values of zeta and L-functions

We show that distinct primitive L-functions can achieve extreme values simultaneously on the critical line. Our proof uses a modification of the resonance method and can be applied to establish simultaneous extreme central values of L-functions in families.Comment: 37 page

Ban the ban: A scientific and cultural analysis of the FDA’s ban on blood donations from men who have sex with men

In recent years, the Lesbian Gay Bisexual Transsexual Queer (LGBTQ) community has experienced a number of triumphs. From the end of the military’s “Don’t Ask, Don’t Tell” policy to the repeal of the Defense of Marriage Act, the political and social landscape in the United States is becoming more inclusive of homosexuality.1 While there still remain many discriminatory practices, a particularly egregious one is the U.S. Food and Drug Administration’s (FDA) ban on blood donations by men who have sex with men. In addition to being societally regressive, this policy frustrates efforts to overcome the nation’s blood shortage. In May 2015, the FDA released a draft guidance document suggesting a shift from the existing lifetime ban to a twelve-month deferral period. While this is a progressive step in the right direction, the new regulation would require donors to remain celibate for twelve months prior to donation, which maintains the categorical association between gay sex, risky sex, and HIV. This updated policy is as discriminatory as the lifetime ban and will not significantly increase the number of eligible donors. A shift away from a categorical and unnecessary ban towards a systematic and scientifically based series of tests and screenings that focus on indicators of risky sex would grow America’s pool of blood donors without increasing the risk of transfusion-related transmission of HIV. Support within the academic community and populations unaffected by the ban would be effective strategies to challenge and ultimately demand the ban’s complete removal

Lower bounds for discrete negative moments of the Riemann zeta function

We prove lower bounds for the discrete negative $2k$th moment of the derivative of the Riemann zeta function for all fractional $k\geqslant 0$. The bounds are in line with a conjecture of Gonek and Hejhal. Along the way, we prove a general formula for the discrete twisted second moment of the Riemann zeta function. This agrees with a conjecture of Conrey and Snaith.Comment: 42 page

E-Nose Vapor Identification Based on Dempster-Shafer Fusion of Multiple Classifiers

Electronic nose (e-nose) vapor identification is an efficient approach to monitor air contaminants in space stations and shuttles in order to ensure the health and safety of astronauts. Data preprocessing (measurement denoising and feature extraction) and pattern classification are important components of an e-nose system. In this paper, a wavelet-based denoising method is applied to filter the noisy sensor measurements. Transient-state features are then extracted from the denoised sensor measurements, and are used to train multiple classifiers such as multi-layer perceptions (MLP), support vector machines (SVM), k nearest neighbor (KNN), and Parzen classifier. The Dempster-Shafer (DS) technique is used at the end to fuse the results of the multiple classifiers to get the final classification. Experimental analysis based on real vapor data shows that the wavelet denoising method can remove both random noise and outliers successfully, and the classification rate can be improved by using classifier fusion

Multistep modelling of teleseismic receiver functions combined with constraints from seismic tomography: Crustal structure beneath southeast China

With a growing number of modern broad-band seismographic stations in Asia, the conditions have improved to allow higher resolution structural studies on regional scales. Here, we perform a receiver-based study of the lithosphere of southeast China using waveform records of excellent quality from 14 Chinese National Digital Seismic Network and four Global Seismic Network stations. Calculating the theoretical receiver functions (RFs) that match the observed RFs from teleseismic waveforms is an established technique for retrieving information about crustal and upper mantle structure beneath a seismic receiver. RFs, however, are predominantly sensitive to the gradients in the lithospheric elastic parameters, and it is impossible to determine a non-unique distribution of seismic parameters such as absolute shear wave speeds as a function of depth unless other geophysical data are combined with RFs. Thus, we combine RFs with independent information from shear and compressional wave speeds above and below the Mohorovičić discontinuity, available from the existing tomographic studies. We introduce a statistical approach for automatically selecting only mutually coherent RFs from a large set of observed waveforms. Furthermore, an interactive forward modelling software is introduced and applied to observed RFs to define a prior, physically acceptable range of elastic parameters in the lithosphere. This is followed by a grid-search for a simple crustal structure. An initial model for a linearized, iterative inversion is constructed from multiple constraints, including results from the grid-search for shear wave speed, the Moho depth versus vp/vs ratio domain search and tomography. The thickness of the crust constrained by our multistep approach appears to be more variable in comparison with tomographic studies, with the crust thinning significantly towards the east. We observe low values of vp/vs ratios across the entire region, which indicates the presence of a very silicic crust. We do not observe any correlation between the crustal thickness or age of the crust with vp/vs ratios, which argues against a notion that there is a simple relationship between mineralogical composition and crustal thickness and age on a global scale