Arabidopsis genomes uncoupled 5 (GUN5) mutant reveals the involvement of Mg-chelatase H subunit in plastid-to-nucleus signal transduction

A plastid-derived signal plays an important role in the coordinated expression of both nuclear- and chloroplast-localized genes that encode photosynthesis-related proteins. Arabidopsis GUN (genomes uncoupled) loci have been identified as components of plastid-to-nucleus signal transduction. Unlike wild-type plants, gun mutants have nuclear Lhcb1 expression in the absence of chloroplast development. We observed a synergistic phenotype in some gun double-mutant combinations, suggesting there are at least two independent pathways in plastid-to-nucleus signal transduction. There is a reduction of chlorophyll accumulation in gun4 and gun5 mutant plants, and a gun4gun5 double mutant shows an albino phenotype. We cloned the GUN5 gene, which encodes the ChlH subunit of Mg-chelatase. We also show that gun2 and gun3 are alleles of the known photomorphogenic mutants, hy1 and hy2, which are required for phytochromobilin synthesis from heme. These findings suggest that certain perturbations of the tetrapyrrole biosynthetic pathway generate a signal from chloroplasts that causes transcriptional repression of nuclear genes encoding plastid-localized proteins. The comparison of mutant phenotypes of gun5 and another Mg-chelatase subunit (ChlI) mutant suggests a specific function for ChlH protein in the plastid-signaling pathway.

Background Checks for Firearms Sales and Loans: Law, History, and Policy

This article examines past and present systems requiring that a person receive permission before buying or borrowing a firearm. The article covers laws from the eighteenth century to the present. Such laws have traditionally been rare in the United States. The major exceptions are antebellum laws of the slaves states, and of those same states immediately after the Civil War, which forbade gun ownership by people of color, unless the individual had been granted government permission. Today “universal background checks” are based on a system created by former New York City Mayor Michael Bloomberg and his “Everytown” lobby. Such laws have been enacted in several states, and also proposed as federal legislation. Besides covering the private sale of firearms, they also cover most loans of firearms and the return of loaned firearms. By requiring that almost all loans and returns may only be processed by a gun store, these laws dangerously constrict responsible firearms activities, such as safety training and safe storage. Massachusetts, Connecticut, and California are among the jurisdictions which have enacted less restrictive, more effective legislation which create controls on private firearms sales, without inflicting so much harm on firearms safety.

The First Century of Right to Arms Litigation

This Article examines state court cases involving the right to arms, during the first century following ratification of the Amendment in 1791. This is not the first article to survey some of those cases. This Article includes additional cases, and details the procedural postures and facts, not only the holdings. The Article closely examines how the Supreme Court integrated the nineteenth century arms cases into Heller and McDonald to shape modern Second Amendment law. Part I briefly explains two English cases which greatly influenced American legal understandings. Semayne’s Case is the foundation of “castle doctrine” — the right to home security which includes the right of armed self-defense in the home. Sir John Knight’s Case fortified the tradition of the right to bear arms, providing that the person must bear arms in a non-terrifying manner. Part II examines American antebellum cases; these are the cases to which Heller looked for guidance on the meaning of the Second Amendment. Part III looks at cases from Reconstruction and the early years of Jim Crow, through 1891. As with the antebellum cases, the large majority of post-war cases are from the Southeast, which during the nineteenth century was the region most ardent for gun control. The heart of gun control country was Tennessee and Arkansas; courts there resisted some infringements of the right to arms, but eventually gave up. Heller and McDonald did not look to the Jim Crow cases as constructive precedents on the Second Amendment.

Activation of polymer blend carbon nanofibres by alkaline hydroxides and their hydrogen storage performances

In the present work we study the hydroxide activation (NaOH and KOH) of phenol-formaldehyde resin derived CNFs prepared by a polymer blend technique to prepare highly porous activated carbon nanofibres (ACNFs). Morphology and textural characteristics of these ACNFs were studied and their hydrogen storage capacities at 77 K (at 0.1 MPa and at high pressures up to 4 MPa) were assessed, and compared, with reported capacities of other porous carbon materials. Phenol-formaldehyde resin derived carbon fibres were successfully activated with these two alkaline hydroxides rendering highly microporous ACNFs with reasonable good activation process yields up to 47 wt.% compared to 7 wt.% yields from steam activation for similar surface areas of 1500 m2/g or higher. These nano-sized activated carbons present interesting H2 storage capacities at 77 K which are comparable, or even higher, to other high quality microporous carbon materials. This observation is due, in part, to their nano-sized diameters allowing to enhance their packing densities to 0.71 g/cm3 and hence their resulting hydrogen storage capacities.

Description of a College Chamber (manuscript copy), ca. 1744

This humorous, rhyming poem appears to have been co-authored by Thomas Handcock of Massachusetts and Richard Waterman of Warwick, Rhode Island. The document is also signed by Catharine Waterman. Neither of the authors attended Harvard College, and the circumstances of this poem's creation are not known. The poem suggests that they composed the poem while visiting - uninvited - the room of "honest Bob." The poem describes the contents of this college chamber, including the following items: an oak table with a broken leg; paper, a pen, and sand for writing; books, including "Scotch songs," philosophy, Euclid, a book of prayer, Tillotson, and French romances; pipes and tobacco; mugs; a broken violin; copperplate and mezzotint prints; a cat; clothes; two globes; a pair of bellows; a broom; a chamber pot; a candle in a bottle; tea; cups and saucers; a letter to Chloe, to whom the room's inhabitant apparently owed money; a powder horn; a fishing net; a rusty gun; a battledore; a shuttlecock; a cannister; a pair of shoes; and a coffee mill. The poem references events related to the War of Austrian Succession (1740-1748); British Vice Admiral Edward Vernon's siege of Portobello (in present-day Panama) in 1739; the "Rushian War" (perhaps the Russo-Swedish War of 1741-1743); and the War of Jenkins' Ear (the cat in the college chamber, like British Captain Robert Jenkins, has lost an ear).

Estudo de camadas anti-reflectoras para células solares

Trabalho de projecto de mestrado, Engenharia da Energia e Ambiente, Universidade de Lisboa, Faculdade de Ciências, 2016

Carbon dioxide assimilation rate, gas and ion composition in samples, and bacterial production of organic matter within and above the Broken Spur and TAG hydrothermal fields, Mid-Atlantic Ridge

Rate of CO2 assimilation was determined above the Broken Spur and TAG active hydrothermal fields for three main ecosystems: (1) hydrothermal vents; (2) 300 m near-bottom layer of plume water; and (3) bottom sediments. In water samples from warm (40-45°C) vents assimilation rates were maximal and reached 2.82-3.76 µg C/l/day. In plume waters CO2 assimilation rates ranged from 0.38 to 0.65 µg C/l/day. In bottom sediments CO2 assimilation rates varied from 0.8 to 28.0 µg C/l/day, rising up to 56 mg C/kg/day near shrimp swarms. In the most active plume zone of the long-living TAG field bacterial production of organic matter (OM) from carbonic is up to 170 mg C/m**2/day); production of autotrophic process of bacterial chemosynthesis reaches about 90% (156 mg C/m**2/day). Thus, chemosynthetic production of OM in September-October is almost equal to that of photosynthetic production in the oceanic region. Bacterial production of OM above the Broken Spur hydrothermal field is one order lower and reaches only 20 mg C/m**2/day.

University of Michigan, 1856

Engraving, 19 x 19 cm. Original painting by J.F. Cropsey dated 1856. Publication information: New York : R. Leggett, 1856

Franklin House, Ann Arbor

Located at the northwest corner of Huron and Main Streets. Publication information: Philadelphia : Bechler, Wenig & Co., 1856

Ann Arbor High School, Michigan

Image from publication: Annual catalogue of the officers and pupils...Ann Arbor, Mich. : School District Board

University of Michigan

Campus view from the northeast after oil painting by J.F. Cropsey utilized as letterhead

Hangsterfer Block in 1862 or 1867 at 316 South State St., Ann Arbor, Mich.

Former site of Kresge's. Source: Ray Hutzel

Main Street North from Liberty Street - Ann Arbor

Plates. 12 pts. in 1 v. Publication information: Chicago : The W. H. Parish publishing co., 1893. Digital image from copy neg in Stugis collection.

Ann Arbor, Michigan

Publication information: Battle Creek, Mich. : A. Ruger [1866]

Main Street, Ann Arbor, Michigan

Photo includes CA Lewis Boots & Shoes, Argus Printing Office, GH Millen Drugs and Medicines, John W. Hunt Hardware Store, German Lutheran School, Tanning Factory, Dietz building. Source: Harry Cole