Reaction of N,N-Dimethyltryptamine with Dichloromethane Under Common Experimental Conditions.

A large number of clinically used drugs and experimental pharmaceuticals possess the N,N-dimethyltryptamine (DMT) structural core. Previous reports have described the reaction of this motif with dichloromethane (DCM), a common laboratory solvent used during extraction and purification, leading to the formation of an undesired quaternary ammonium salt byproduct. However, the kinetics of this reaction under various conditions have not been thoroughly described. Here, we report a series of experiments designed to simulate the exposure of DMT to DCM that would take place during extraction from plant material, biphasic aqueous work-up, or column chromatography purification. We find that the quaternary ammonium salt byproduct forms at an exceedingly slow rate, only accumulates to a significant extent upon prolonged exposure of DMT to DCM, and is readily extracted into water. Our results suggest that DMT can be exposed to DCM under conditions where contact times are limited (<30 min) with minimal risk of degradation and that this byproduct is not observed following aqueous extraction. However, alternative solvents should be considered when the experimental conditions require longer contact times. Our work has important implications for preparing a wide-range of pharmaceuticals bearing the DMT structural motif in high yields and purities

Dusty Exoplanetary Debris Disks in the Single-Temperature Blackbody Plane

The 21st European Workshop on White Dwarfs was held in Austin, TX from July 23rd to 27th of 2018We present a bulk sample analysis of the metal polluted white dwarfs which also host infrared bright dusty debris disks, known to be direct signatures of an active exoplanetary accretion source. We explore the relative positions of these systems in a “single-temperature blackbody plane”, defined as the temperature and radius of a single temperature blackbody as fitted to the infrared excess. We find that the handful of dust systems which also host gaseous debris in emission congregate along the high temperature boundary of the dust disk region in the single-temperature blackbody plane. We discuss interpretations of this boundary and propose the single-temperature blackbody plane selection technique for use in future targeted searches of gaseous emission.Astronom

Axial Ratio of Edge-On Spiral Galaxies as a Test For Extended Bright Radio Halos

We use surface brightness contour maps of nearby edge-on spiral galaxies to determine whether extended bright radio halos are common. In particular, we test a recent model of the spatial structure of the diffuse radio continuum by Subrahmanyan and Cowsik which posits that a substantial fraction of the observed high-latitude surface brightness originates from an extended Galactic halo of uniform emissivity. Measurements of the axial ratio of emission contours within a sample of normal spiral galaxies at 1500 MHz and below show no evidence for such a bright, extended radio halo. Either the Galaxy is atypical compared to nearby quiescent spirals or the bulk of the observed high-latitude emission does not originate from this type of extended halo.Comment: 6 Pages, 4 Figures, 1 Table; To Appear In ApJ Letter

TAXATION-CAPITAL STOCK TAX-WHAT CONSTITUTES DOING BUSINESS

The capital stock tax is an excise tax levied not on the business itself but on the exercise of the privilege of doing business in a corporate capacity; hence the determination of tax liability involves a decision in each case as to whether the corporation is carrying on or doing business within the meaning of the tax statutes

Proceedings of the Eighth Annual Biochemical Engineering Symposium

Contents Effects of Swell-Shear Treatment on the Digestibility of Cellulosics , Dou-Houng Hwang, UMC Application of Material and Energy Balance Regularities to Biomass Production from Cellulosic Substrates , Y.H. Lee, KSU Immobilization of Aspergillus niger beta-Xylosidase , Gbekeloluwa B. Oguntimein, ISU The Effect of the Major Structural Parameters of Cellulose on Enzymatic Hydrolysis , David H. Beardmore, Y.H. Lee, and L.T. Fan, KSU Purification of a High Molecular Weight Hemicellulase , Ricardo A. Fournier, ISU Aerobic Fermentation of Banana Pulp by Aspergillus Fumigatus , Stephen Lorbert, UMC Purification and Properties of Two Very Small Xylanases , Chih-hen Kiang, ISU Testing Theoretical Models for Cellulose Enzymatic Hydrolysis , Lin-Chang Chiang, UMC Utilization of Material and Energy Balances in Hydrocarbon Fermentation , Alexis Ferrer, KSU Purification of a Series of Closely Related Xylanases , Mary M. Frederick, ISUhttps://lib.dr.iastate.edu/bce_proceedings/1007/thumbnail.jp

On the Use of Surrogate Functions for Mixed Variable Optimization of Simulated Systems

This research considers the efficient numerical solution of linearly constrained mixed variable programming (MVP) problems, in which the objective function is a black-box stochastic simulation, function evaluations may be computationally expensive, and derivative information is typically not available. MVP problems are those with a mixture of continuous, integer, and categorical variables, the latter of which may take on values only from a predefined list and may even be non-numeric. Mixed Variable Generalized Pattern Search with Ranking and Selection (MGPS-RS) is the only existing, provably convergent algorithm that can be applied to this class of problems. Present in this algorithm is an optional framework for constructing and managing less expensive surrogate functions as a means to reduce the number of true function evaluations that are required to find approximate solutions. In this research, the NOMADm software package, an implementation of pattern search for deterministic MVP problems, is modified to incorporate a sequential selection with memory (SSM) ranking and selection procedure for handling stochastic problems. In doing so, the underlying algorithm is modified to make the application of surrogates more efficient. A second class of surrogates based on the Nadaraya-Watson kernel regression estimator is also added to the software. Preliminary computational testing of the modified software is performed to characterize the relative efficiency of selected surrogate functions for mixed variable optimization in simulated systems

An Examination of Gender Differences in Today\u27s Mathematics Classrooms: Exploring Single-Gender Mathematics Classrooms

Much research identifies a gender gap in mathematics, and some research points to single-gender math classrooms as a solution to the math gender divide. The author conducted a seven week study in which she divided fifty fifth grade students into singlegender mathematics classes. She wanted to examine if single-gender math classes affected the math achievement and attitudes of her female students. Upon completion of the study the author found there was no statistical significance in the girls’ achievement between a single-gender classroom and a coeducational classroom. There was a significant difference in the girls’ perceptions as to how they best learn math

The Corralitos Observatory program for the detection of lunar transient phenomena

This is a final report on the establishment, observing procedures, and observational results of a survey program for the detection of lunar transient phenomena (LTP's) by electro-optical image conversion means. For survey, a unique detection system with an image orthicon was used as the primary element in conjunction with a 24-in. f/20 Cassegrainian telescope. Observations in three spectral ranges, with 6,466 man-hours of observing, were actually performed during the period from October 27, 1965, to April 26, 1972. Within this entire period, no color or feature change within the detection capabilities of the instrumentation was observed, either independently or in follow up of amateur LTP reports, with the exception of one general bluing and several localized bluings (probably ascribable to the effects of the terrestrial atmosphere) that were observed solely by the Corralitos system. A table is presented indicating amateur and professional reports of LTP's and the results of efforts to confirm these reports through the Corralitos system