A photochemical flow reactor for large scale syntheses of aglain and rocaglate natural product analogues

Published in final edited form as: Bioorg Med Chem. 2017 Dec 1; 25(23): 6197–6202. Published online 2017 Jun 11. doi: [10.1016/j.bmc.2017.06.010]Herein, we report the development of continuous flow photoreactors for large scale ESIPT-mediated [3+2]-photocycloaddition of 2-(p-methoxyphenyl)-3-hydroxyflavone and cinnamate-derived dipolarophiles. These reactors can be efficiently numbered up to increase throughput two orders of magnitude greater than the corresponding batch reactions.Financial support from Boston University and National Institutes of Health (ABB R33AI105944) is gratefully acknowledged. We thank Dr. Norman Lee (Boston University) for high-resolution mass spectrometry data. NMR (CHE-0619339) and MS (CHE-0443618 facilities at Boston University are supported by the NSF. (Boston University; ABB R33AI105944 - National Institutes of Health; CHE-0619339 - NSF; CHE-0443618 - NSF)Accepted manuscrip

Observations of attenuation at 20.6, 31.65 and 90.0 GHz: Preliminary results from Wallops Island, VA

Ground based radiometric observations of atmospheric attenuation at 20.6, 31.65, and 90.0 GHz were made at Wallops Island, Virginia during April and May 1989. Early results from the analysis of the data set are compared with previous observations from California and Colorado. The relative attenuation ratios observed at each frequency during clear, cloudy, and rainy conditions are shown. Plans for complete analysis of the data are described

Archival investigation of a late 19th century accounting information system: The use of decision aids in the American printing Industry

This study investigates management\u27s use of decision aids within the context of an accounting information system of a late 19th century American printing firm. Our findings suggest that the use of decision aids by management transformed traditional ac­counting techniques and the cost accounting system into an intri­cate accounting information system by 1880. These decision aids allowed managers to manipulate accounting information to support decisions involving pricing, cost allocation and estimation, profitability assessment, management of receivables, and inventory control. The findings shed new light on the early work of Alexander Hamilton Church on the issue of idle time accounting and raises questions about the uniform costing movement in the American printing industry

Remodelling of the natural product fumagillol employing a reaction discovery approach

In the search for new biologically active molecules, diversity-oriented synthetic strategies break through the limitation of traditional library synthesis by sampling new chemical space. Many natural products can be regarded as intriguing starting points for diversity-oriented synthesis, wherein stereochemically rich core structures may be reorganized into chemotypes that are distinctly different from the parent structure. Ideally, to be suited to library applications, such transformations should be general and involve few steps. With this objective in mind, the highly oxygenated natural product fumagillol has been successfully remodelled in several ways using a reaction-discovery-based approach. In reactions with amines, excellent regiocontrol in a bis-epoxide opening/cyclization sequence can be obtained by size-dependent interaction of an appropriate catalyst with the parent molecule, forming either perhydroisoindole or perhydroisoquinoline products. Perhydroisoindoles can be further remodelled by cascade processes to afford either morpholinone or bridged 4,1-benzoxazepine-containing structures.P50 GM067041 - NIGMS NIH HHS; P50 GM067041-07 - NIGMS NIH HHS; P50 GM067041-08 - NIGMS NIH HHS; P50 GM067041-09 - NIGMS NIH HH

Intersubband transitions in nonpolar GaN/Al(Ga)N heterostructures in the short and mid-wavelength infrared regions

This paper assesses nonpolar m- and a-plane GaN/Al(Ga)N multi-quantum-wells grown on bulk GaN for intersubband optoelectronics in the short- and mid-wavelength infrared ranges. The characterization results are compared to those for reference samples grown on the polar c-plane, and are verified by self-consistent Schr\"odinger-Poisson calculations. The best results in terms of mosaicity, surface roughness, photoluminescence linewidth and intensity, as well as intersubband absorption are obtained from m-plane structures, which display room-temperature intersubband absorption in the range from 1.5 to 2.9 um. Based on these results, a series of m-plane GaN/AlGaN multi-quantum-wells were designed to determine the accessible spectral range in the mid-infrared. These samples exhibit tunable room-temperature intersubband absorption from 4.0 to 5.8 um, the long-wavelength limit being set by the absorption associated with the second order of the Reststrahlen band in the GaN substrates

Wall turbulence control

A variety of wall turbulence control devices which were experimentally investigated are discussed; these include devices for burst control, alteration of outer flow structures, large eddy substitution, increased heat transfer efficiency, and reduction of wall pressure fluctuations. Control of pre-burst flow was demonstrated with a single, traveling surface depression which is phase-locked to elements of the burst production process. Another approach to wall turbulence control is to interfere with the outer layer coherent structures. A device in the outer part of a boundary layer was shown to suppress turbulence and reduce drag by opposing both the mean and unsteady vorticity in the boundary layer. Large eddy substitution is a method in which streamline curvature is introduced into the boundary layer in the form of streamwise vortices. Riblets, which were already shown to reduce turbulent drag, were also shown to exhibit superior heat transfer characteristics. Heat transfer efficiency as measured by the Reynolds Analogy Factor was shown to be as much as 36 percent greater than a smooth flat plate in a turbulent boundary layer. Large Eddy Break-Up (LEBU) which are also known to reduce turbulent drag were shown to reduce turbulent wall pressure fluctuation

Accounting and financial reporting by a late 18th century American charity

Empirical research to date has neglected accounting and external financial reporting among 18th century American charitable institutions. Contemporary understanding of 18th century American practices is supported by evidence relating to commercial transactions primarily among colonial merchants. Our study examines the accounting and financial reporting of the Charleston Orphan House, the first municipal orphanage in America, from its inception in 1790 through its first five years of operations. The institution was established by city ordinance in 1790 which required the institution to keep a book of fair and regular accounts of all receipts and expenditures which will be subject at all times to the inspection of the Commissioners. The ordinance charged the orphanage\u27s Committee on Accounts to audit its accounts.The City Council required the institution\u27s board chairman to countersign the financial statements in 1792 before subjecting them to a second audit. The Orphan House employed a system of account books that recorded and facilitated the reporting of expenditures and sources of funds. Accounting and external reporting may have been legitimizing factors to overcome the liability of newness by promoting a sense of propriety and transparency among benefactors