9,814 research outputs found
The nucleotide sequence of a human immnnoglobulin C-gamma-1 gene
We report the nucleotide sequence of a gene encoding the constant region of a human immnnoglobulin Ī³1 heavy chain (CĪ³1). A comparison of this sequence with those of the CĪ³2 and CĪ³4 genes reveals that these three human CĪ³ genes share considerable homology in both coding and noncoding regions. The nucleotide sequence differences indicate that these genes diverged from one another approximately 6ā8 million years ago. An examination of hinge exons shows that these coding regions have evolved more rapidly than any other areas of the CĪ³ genes in terms of both base substitution and deletionāinsertion events. Coding sequence diversity also is observed in areas of CH domains which border the hinge
Trust the Process? Rethinking Procedural Due Process and the Presidentās Emergency Powers over the Digital Economy
To protect U.S. user data from foreign threats, presidents have wielded their emergency power to ban transactions with certain technology companies. This emergency power, if unchecked, threatens both the procedural rights of some technology companies and U.S. constitutional structure.
Concerning procedural rights, this Note evaluates existing procedural due process jurisprudence to identify the scope of these protections in the data security context, which remains unexplored in scholarship and judicial opinions. For guidance, this Note looks to cases involving counterterrorist financing and national security reviews of foreign investment, and it concludes that procedural due process protects many technology companies that collect personally identifiable information. In particular, due process requires the government to provide these companies with meaningful notice and an opportunity to respond before the president wields emergency powers that slash these companiesā economic interests. These predeprivation procedural rights significantly safeguard affected companies by giving them time to respond.
However, due process alone will not prevent the emergency executive from running roughshod over the Constitutionās system of checks and balances. This Note argues, as have many commentators, that Congress should recalibrate the balance: Congress should amend IEEPA to include a sunset provision that would limit the duration of any national emergency until Congress affirmatively votes to extend it through a fast-track process. Ultimately, procedural due process and political process must work hand in hand to protect both constitutional rights and structures
The Biggest Snowball Fight in Earth History: Stratigraphy, Facies Analysis, and Geochronology of the Pocatello Formation
The Snowball Earth Hypothesis details a time in Earthās history (the Cryogenian period) where the entire planet was encapsulated by kilometer thick ice sheets for two, multi-million-year glaciations. The first, known as the Sturtian, lasted from 717 ā 660 million years ago while the second, known as the Marinoan, lasted form approximately 650 ā 635 million years ago. Snowball Earth was caused by a few processes that sort of built upon each other: Rodinia began splitting apart ~740 million years ago which allowed for increased rates of silicate weathering. High rates of silicate weathering resulted in CO2 drawdown which in turn caused the global temperature to drop. The gradual drop in temperature allowed for polar ice to advance and, once the ice reached a critical latitude, the earth experienced a runaway ice albedo effect ā meaning ice advanced uncontrollably all the way to the equator ā resulting in a completely ice-covered planet.
Evidence for Snowball Earth comes in the form of paleomagnetic data that show that Rodinia was rifting at this time, a global distribution and synchroneity of Snowball Earth deposits, carbon isotope ratios, and cap carbonates (a unique lithology present only in Snowball Earth deposits). In Pocatello, Idaho, geologists have identified deposits (the Pocatello Formation) that fall within the age range of Snowball Earth and that exhibit similar lithologic characteristics to other known Snowball Earth deposits. The goal of this study is to determine whether the Pocatello Formation was deposited during Snowball Earth, and if it is, which glaciation(s)/deglaciation(s) it was deposited during. To accomplish this goal, we conducted field work to characterize the different lithologies of the Pocatello Formation and then we used a radiometric dating technique called chemical abrasion ā isotope dilution ā thermal ionization mass-spectrometry to find out exactly how old the Pocatello Formaton is.
Our results show that the Pocatello Formation is host to Sturtian glacial deposits, Marinoan glacial deposits, and Marinoan deglacial deposits. These findings will allow for: the revision to local stratigraphy and age boundaries, correlation of the Pocatello Formation with other Snowball Earth deposits worldwide, and further insight into the Cryogenian period
Clues to the Origin of the Mass-Metallicity Relation: Dependence on Star Formation Rate and Galaxy Size
We use a sample of 43,690 galaxies selected from the Sloan Digital Sky Survey
Data Release 4 to study the systematic effects of specific star formation rate
(SSFR) and galaxy size (as measured by the half light radius, r_h) on the
mass-metallicity relation. We find that galaxies with high SSFR or large r_h
for their stellar mass have systematically lower gas phase-metallicities (by up
to 0.2 dex) than galaxies with low SSFR or small r_h. We discuss possible
origins for these dependencies, including galactic winds/outflows, abundance
gradients, environment and star formation rate efficiencies.Comment: Accepted by ApJ Letter
Methods for structural design at elevated temperatures
A procedure which can be used to design elevated temperature structures is discussed. The desired goal is to have the same confidence in the structural integrity at elevated temperature as the factor of safety gives on mechanical loads at room temperature. Methods of design and analysis for creep, creep rupture, and creep buckling are presented. Example problems are included to illustrate the analytical methods. Creep data for some common structural materials are presented. Appendix B is description, user's manual, and listing for the creep analysis program. The program predicts time to a given creep or to creep rupture for a material subjected to a specified stress-temperature-time spectrum. Fatigue at elevated temperature is discussed. Methods of analysis for high stress-low cycle fatigue, fatigue below the creep range, and fatigue in the creep range are included. The interaction of thermal fatigue and mechanical loads is considered, and a detailed approach to fatigue analysis is given for structures operating below the creep range
Sagittal depth of the more common disposable and daily wear soft contact lenses
Inaccurate soft contact lens parameters can create a variety of problems for the practitioner and patient. Most soft contact lenses are dispensed to the patient without the benefit of verification. Of particular importance, sagittal depth best predicts tightness or looseness of fit. A tight or loose fitting lens can cause many problems for the patient. Manufacturer-published values of sagittal depth may vary from the actual measured parameter. Sagittal depth, diameter, and power of 215 soft contact lenses were measured for 11 of the more common disposable/daily wear brands. Measurements were made with a prototype of the Hydroscopeā¢ contact lens analyzing device. Tables and graphs are included which can aid the practitioner in fitting these lenses. The effect of eye temperature, approximately 93Ā°F, versus room temperature was analyzed. No significant change in the measured parameters was noted
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CO and CI maps of the starburst galaxy M82
The first map of an external galaxy in the 3Pā - 3P0 fine-structure line of atomic carbon (CI) is presented towards the nucleus of the starbuster M82, and compared with the distinction of the CO J = 4 - 3 molecular emission. The CI traces features that are seen in lower transition CO maps, and shows that CI and the CO are well mixed and have similar spatial distributions. There are small differences between the CO J = 4 - 3 line and lower transition CO data towards the NE part of the molecular ring, where the emission is less prominent. The abundance ratio [CI]/[CO] across M82 is very high, with an average value ~ 0.5 across most of the nucleus, a factor at least 5 times that which is typical of dense molecular cloud cores seen in our own Galaxy. This means that on average, CI is overabundant towards M82. This result can be explained using models which provide enhancements to the CI abundance above normal Interstellar Medium values, a result of a greater cosmic ray flux in M82, or where there is substantial mixing of the gas
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