Synoptic revision of the United States scarab beetles of the subfamily Dynastinae, No.1: Tribe Cyclocephalini

The important subfamily Dynastinae has for some time been relatively neglected, taxonomically speaking, and only in the past few years have new species been described or the larval characters of many species better characterized. In all collections I have seen,numerous United States species are grossly misidentified, and it is hoped that the present papers will help to rectify this condition. Ritcher\u27s paper (1944) is an excellent contribution to the immature stages of these insects. His title, however, Dynastinae of the United States, is very misleading, because this paper includes only a small proportion of the described United States species, and only those adults are mentioned of which he had larvae; thus, of the 18 described genera and 119 United States species listed as valid in Arrow\u27s latest catalogue (1937) Ritcher treats the larvae and adults of but 12 genera and 20 species. Even though a number of these 119 names are not valid, many of them are important and well-known species and must be considered. Also, two generic and three specific names that Ritcher uses have been changed; regardless of these taxonomic errors, the paper is very important from an economic standpoint. Casey\u27s studies in this group have greatly enlarged our synonymy because of his practice of naming trifling variants, but at the same time his Memoirs (1915) gave more detailed information and pointed out more new characters and relationships than had. any of his predecessors or contemporaries, including Horn and LeConte; it is indeed too bad that Colonel Casey\u27s idea of a species was not exactly that of the vast majority of coleopterists; otherwise his work in this family would have stood for some time. I have had the privilege of studying and dissecting all of Casey\u27s scarab types through the courtesy of Dr. A. Wetmore and Dr. E. A. Chapin, of the U. S. National Museum, to both of whom I am indebted for many favors in the past. The Dynastinae in most instances possess well-chitinized genitalia, and the characters of those of the male are very helpful in specific determination, and wider use should be made of them. Indeed, in such difficult genera as Cyclocephala, it is necessary to dissect and compare the male genitalia in order properly to place many of the troublesome variants. Dynastine bibliography is now so long and detailed in most. genera that very little is to be gained by citing every unimportant reference; as this has already\u27 been done in Arrow\u27s catalogue of world Dynastinae. Thus, in the present series of papers, of which this is. the first of four, only the important ,bibliographical references have been selected and a list of those cited is given at the end..-of each paper. Keys to all tribes and genera will be given in the last paper of the series. Genus Ancolnatha Erichson Genus Dyscinetus Harold Genus Cyclocephala Latreille Aspidolea texana Hahn

Synoptic revision of the United States scarab beetles of the subfamily Dynastinae, No. 4: Tribes Oryctini (part), Dynastini, and Phileurini

This paper is the fourth in the series of my United States dynastine scarab beetle studies and completes the specific listings and notes. The fifth, and last, part will include a complete classification of the tribes and genera, from the Nearctic standpoint. Genus Aphonus LeConte Tribe DYNASTINI -- Genus Dynastes Kirby, Genus Megasoma Kirb Tribe PHILEURINI -- Genus Archopbileurus Kolbe, Genus Phileurus Latreill

Synoptic revision of the United States scarab beetles of the subfamily Dynastinae, No.1: Tribe Cyclocephalini

The important subfamily Dynastinae has for some time been relatively neglected, taxonomically speaking, and only in the past few years have new species been described or the larval characters of many species better characterized. In all collections I have seen,numerous United States species are grossly misidentified, and it is hoped that the present papers will help to rectify this condition. Ritcher\u27s paper (1944) is an excellent contribution to the immature stages of these insects. His title, however, Dynastinae of the United States, is very misleading, because this paper includes only a small proportion of the described United States species, and only those adults are mentioned of which he had larvae; thus, of the 18 described genera and 119 United States species listed as valid in Arrow\u27s latest catalogue (1937) Ritcher treats the larvae and adults of but 12 genera and 20 species. Even though a number of these 119 names are not valid, many of them are important and well-known species and must be considered. Also, two generic and three specific names that Ritcher uses have been changed; regardless of these taxonomic errors, the paper is very important from an economic standpoint. Casey\u27s studies in this group have greatly enlarged our synonymy because of his practice of naming trifling variants, but at the same time his Memoirs (1915) gave more detailed information and pointed out more new characters and relationships than had. any of his predecessors or contemporaries, including Horn and LeConte; it is indeed too bad that Colonel Casey\u27s idea of a species was not exactly that of the vast majority of coleopterists; otherwise his work in this family would have stood for some time. I have had the privilege of studying and dissecting all of Casey\u27s scarab types through the courtesy of Dr. A. Wetmore and Dr. E. A. Chapin, of the U. S. National Museum, to both of whom I am indebted for many favors in the past. The Dynastinae in most instances possess well-chitinized genitalia, and the characters of those of the male are very helpful in specific determination, and wider use should be made of them. Indeed, in such difficult genera as Cyclocephala, it is necessary to dissect and compare the male genitalia in order properly to place many of the troublesome variants. Dynastine bibliography is now so long and detailed in most. genera that very little is to be gained by citing every unimportant reference; as this has already\u27 been done in Arrow\u27s catalogue of world Dynastinae. Thus, in the present series of papers, of which this is. the first of four, only the important ,bibliographical references have been selected and a list of those cited is given at the end..-of each paper. Keys to all tribes and genera will be given in the last paper of the series. Genus Ancolnatha Erichson Genus Dyscinetus Harold Genus Cyclocephala Latreille Aspidolea texana Hahn

Investigation of reliability attributes and accelerated stress factors on terrestrial solar cells

Major effort during this reporting period was devoted to two tasks: improvement of the electrical measurement instrumentation through the design and construction of a microcomputer controlled short interval tester, and better understanding of second quadrant behavior by developing a mathematical model relating cell temperature to electrical characteristics. In addition, some preliminary work is reported on an investigation into color changes observed after stressing

Raman effect in AlGaAs waveguides for subpicosecond pulses

The Raman effect in semiconductor waveguides below half‐gap is studied both experimentally and numerically. We report the depolarized Raman gain spectra up to 300 cm−1 in Al0.24Ga0.76As at pump wavelengths of 0.515 and 1.55 μm from the measurement of the absolute Raman scattering cross sections using GaAs as a reference scatterer. In addition, the coupled propagation equations for the AlGaAs waveguides are modified to include the Raman effect. By solving the coupled propagation equations numerically, we verify that the energy transfer between two orthogonally polarized pulses demonstrated in previous pump‐probe experiments [M. N. Islam et al., J. Appl. Phys. 71, 1927 (1992)] is caused by Raman effect. We also show numerically that the Raman effect induces spectral distortions on the pulses, and the energy transfer is inversely proportional to the pulse widths. The energy transfer results in a severe cross‐talk problem for sub‐picosecond pulses in AlGaAs waveguides. For example, the energy exchange is about 30% for 300 fs pulses under π phase shift conditions. Therefore, the Raman effect limits the performance of semiconductor waveguides in optical switching applications for sub‐picosecond pulses. © 1995 American Institute of Physics.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/71265/2/JAPIAU-78-4-2198-1.pd

Lessons from development: A role for asymmetric stem cell division in cancer

AbstractAsymmetric stem cell division has emerged as a major regulatory mechanism for physiologic control of stem cell numbers. Reinvigoration of the cancer stem cell theory suggests that tumorigenesis may be regulated by maintaining the balance between asymmetric and symmetric cell division. Therefore, mutations affecting this balance could result in aberrant expansion of stem cells. Although a number of molecules have been implicated in regulation of asymmetric stem cell division, here, we highlight known tumor suppressors with established roles in this process. While a subset of these tumor suppressors were originally defined in developmental contexts, recent investigations reveal they are also lost or mutated in human cancers. Mutations in tumor suppressors involved in asymmetric stem cell division provide mechanisms by which cancer stem cells can hyperproliferate and offer an intriguing new focus for understanding cancer biology. Our discussion of this emerging research area derives insight from a frontier area of basic science and links these discoveries to human tumorigenesis. This highlights an important new focus for understanding the mechanism underlying expansion of cancer stem cells in driving tumorigenesis

Boosted three-dimensional black-hole evolutions with singularity excision

Binary black hole interactions provide potentially the strongest source of gravitational radiation for detectors currently under development. We present some results from the Binary Black Hole Grand Challenge Alliance three- dimensional Cauchy evolution module. These constitute essential steps towards modeling such interactions and predicting gravitational radiation waveforms. We report on single black hole evolutions and the first successful demonstration of a black hole moving freely through a three-dimensional computational grid via a Cauchy evolution: a hole moving ~6M at 0.1c during a total evolution of duration ~60M

Measurement of Unpolarized and Polarized Cross Sections for Deeply Virtual Compton Scattering on the Proton at Jefferson Laboratory with CLAS

This paper reports the measurement of polarized and unpolarized cross sections for the ep → e \u27p\u27 γ reaction, which is composed of deeply virtual Compton scattering (DVCS) and Bethe-Heitler (BH) processes, at an electron beam energy of 5.88 GeV at the Thomas Jefferson National Accelerator Facility using the Large Acceptance Spectrometer CLAS. The unpolarized cross sections and polarized cross section differences have been measured over broad kinematics, 0.10 2 \u3c 4.8 GeV2,and 0.09 \u3c −t\u3c 2.00 GeV2. The results are found to be consistent with previous CLAS data, and these new data are discussed in the framework of the generalized parton distribution approach. Calculations with two widely used phenomenological models are approximately compatible with the experimental results over a large portion of the kinematic range of the data

Stable characteristic evolution of generic 3-dimensional single-black-hole spacetimes

We report new results which establish that the accurate 3-dimensional numerical simulation of generic single-black-hole spacetimes has been achieved by characteristic evolution with unlimited long term stability. Our results cover a selection of distorted, moving and spinning single black holes, with evolution times up to 60,000M.Comment: 4 pages, 3 figure