Solid State NMR Analysis of Insect Wing Membranes

Solid State NMR is a powerful tool for analyzing the chemical composition of insects. Previous studies have used Solid State NMR to investigate the chemical composition and investigate the sclerotization (tanning) process of insect exoskeletons. Acquiring sufficient exoskeleton sample for analysis has been relatively simple. This is however not the case for other components of an insect’s physiology, particularly the wing membrane material. The wings of an insect only compose a small percentage of their overall body mass, and many hundreds to thousands of insects must be processed in order to achieve a few milligrams of wing membrane sample. The wing membranes which are in our interest are particularly challenging to collect as they are very small, surrounded by unwanted veins, extremely thin and nearly transparent. Compounding these difficulties is the factor of NMR signal strength due to low 13C isotopic natural abundance. The task of isotopically labelling living organisms such as insects ranges from challenging to impossible. Consequently NMR signal enhancement techniques are necessary to generate high quality useful spectra. Solid State NMR has been used to investigate the chemical composition of the wing membranes of cicadas (Magicicada cassini), honeybees (Apis mellifera ligustica), ladybugs (Hippodamia convergens), and amber phantom butterflies (Haetera piera). DNP-MAS Solid State NMR has been used to investigate the chemical composition of cicada wing membranes of a small natural abundance sample, yielding high quality one-dimensional and two-dimensional spectra

Alien Registration- Eddy, Samuel (Wade, Aroostook County)

https://digitalmaine.com/alien_docs/32691/thumbnail.jp

Climate in Greco-Roman History

Examination of the rings of giant California sequoias, along with other contemporaneous physical evidence, provides an understanding of certain climatic changes in the classical world and suggests some surprising determinants of Greco-Roman social and political history. Page 19

New Distributional Records of Some Minnesota Fishes

Minnesota is almost unique in that its waters drain by three divergent courses: the Red River to the Arctic, the Great Lakes to the Gulf of St. Lawrence and the Mississippi River to the Gulf of Mexico. The close proximity of the headwaters of these several drainages present opportunities for certain species to move from one basin to another. Species restricted to the Arctic basin have their southern limits in northern and western Minnesota. Many eastern and southern species have their northern and western limits within the state. In spite of the fact that intensive collecting has been carried on since 1890 by various workers new records or range extensions are made each year

The Plankton of Lake Michigan

The chief purposes of this paper are: (1) to present a general picture of the plankton of Lake Michigan, (2) to determine the relative abundance of its constituent organisms, and (3) to incorporate and summarize the facts now known relating to the plankton of the Great Lakes. The data for the present paper were obtained from two series of collections made from Lake Michigan in 1887-1888 and 1926 1927. Fifty silk-net tows (Table I) were made by the Illinois State Laboratory of Natural History from November, 1887 to November, 1888 from the breakwater at Chicago. Quantitative silk-net and filter-paper collections (Table II) were made October 16-17, 1926 at Indiana State Dunes Park and Michigan City, Indiana, and near Sawyer, Michigan. Quantitative collections (Table III) were also made May 14 15, 1927 at Dunes Park and Gary, Indiana and July 10, 1927 at Chicago, Illinois. All of these were surface tows near the shore, so that the material in this paper relates only to surface and in-shore conditions. No investigation has been reported on the plankton or the conditions in the central area of the lake.published or submitted for publicationis peer reviewe