3,545 research outputs found
New looks at and for Onespa, Buzyges, and Librita (Lepidoptera: Hesperiidae: Hesperiinae), with new combinations and descriptions of a new genus and six new species
Thirteen species of skippers (six newly described; Lepidoptera: Hesperiidae: Hesperiinae: Hesperiini) from higher elevations of Mexico and Central America are reviewed. These are included in four genera (one newly described), some with proposed new combinations. Onespa Steinhauser, 1974, originally described as monotypic, is shown to include three species in addition to its type species, Onespa nubis Steinhauser, 1974. One of these, Atrytone gala Godman, 1900, that has been misplaced in several genera since its description, represents a new combination. The other two species, distributed in montane habitats in northwestern Mexico and in Costa Rica, are described as new. Buzyges Godman, 1900, distributed in Mexico and Central America and also formerly considered monotypic, is shown to embrace four species. Besides the type species, Buzyges idothea Godman, 1900, two species long placed in Poanes Scudder, 1872, Pamphila rolla Mabille, 1883, and Poanes benito Freeman, 1979, are included as new combinations. Another species, known only from Costa Rica, is described as new. These are united by several superficial characters, but especially by genital morphology of both sexes. Librita Evans, 1955, was described to include three species of which one, Librita raspa Evans, 1955, was subsequently removed. Augiades heras Godman, 1900 is here also removed from Librita and placed in a new genus with three previously undescribed species. This completes the disintegration of Librita, which is now monotypic. The four genera, although exhibiting similarities suggesting potential alliance, differ in their unique combinations of several superficial and genital traits from each other and other hesperiine skippers
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The Debt Limit: History and Recent Increases
[Excerpt] The statutory debt limit applies to almost all federal debt. The limit applies to federal debt held by the public (that is, debt held outside the federal government itself) and to federal debt held by the government’s own accounts. Federal trust funds, such as Social Security, Medicare, Transportation, and Civil Service Retirement accounts, hold most of this internally held debt. The government’s surpluses or deficits determine essentially all of the change in debt held by the public. The government’s on-budget fiscal balance, which excludes a U.S. Postal Service net surplus or deficit and a large Social Security surplus of payroll taxes net of paid benefits, does not directly affect debt held in government accounts. Increases or decreases in debt held by government accounts result from net financial flows into accounts holding the debt, such as the Social Security Trust Fund. Legal requirements and government accounting practices also affect levels of debt held by government accounts.
On August 2, 2011, President Obama signed into law the Budget Control Act of 2011 (BCA; S.365), after an extended debt limit episode. The federal debt reached its statutory limit on May 16, 2011, prompting Treasury Secretary Timothy Geithner to declare a debt issuance suspension period, allowing certain extraordinary measures to extend Treasury’s borrowing capacity. The BCA included provisions aimed at deficit reduction and would allow the debt limit to rise between 2,400 billion in three stages, with the latter two subject to congressional disapproval. Two of the three increases, totaling $900 billion, have occurred, and a request for a third increase is likely to occur in mid-January 2012
The type of Copaeodes chromis Skinner, 1919 (Lepidoptera: Hesperiidae: Hesperiinae)
The holotype of Copaeodes chromis Skinner, 1919 (Lepidoptera: Hesperiidae), housed at the Carnegie Museum of Natural History, is a typical specimen of Zariaspes mythecus Godman, 1900
Analyzing Machupo virus-receptor binding by molecular dynamics simulations
In many biological applications, we would like to be able to computationally
predict mutational effects on affinity in protein-protein interactions.
However, many commonly used methods to predict these effects perform poorly in
important test cases. In particular, the effects of multiple mutations,
non-alanine substitutions, and flexible loops are difficult to predict with
available tools and protocols. We present here an existing method applied in a
novel way to a new test case; we interrogate affinity differences resulting
from mutations in a host-virus protein-protein interface. We use steered
molecular dynamics (SMD) to computationally pull the machupo virus (MACV) spike
glycoprotein (GP1) away from the human transferrin receptor (hTfR1). We then
approximate affinity using the maximum applied force of separation and the area
under the force-versus-distance curve. We find, even without the rigor and
planning required for free energy calculations, that these quantities can
provide novel biophysical insight into the GP1/hTfR1 interaction. First, with
no prior knowledge of the system we can differentiate among wild type and
mutant complexes. Moreover, we show that this simple SMD scheme correlates well
with relative free energy differences computed via free energy perturbation.
Second, although the static co-crystal structure shows two large
hydrogen-bonding networks in the GP1/hTfR1 interface, our simulations indicate
that one of them may not be important for tight binding. Third, one viral site
known to be critical for infection may mark an important evolutionary
suppressor site for infection-resistant hTfR1 mutants. Finally, our approach
provides a framework to compare the effects of multiple mutations, individually
and jointly, on protein-protein interactions.Comment: 33 pages, 8 figures, 5 table
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The Debt Limit: History and Recent Increases
This report gives an overview of the federal debt limit, its history, and recent increase
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Discretionary Budget Authority by Subfunction: An Overview
This report provides a graphical overview of historical trends in discretionary budget authority (BA) from FY1976 through FY2011, enacted levels for FY2012 spending, and the levels consistent with President Obama's proposals for FY2013 through FY2017. It also includes a background on functional categories and a section discussing historical spending trends
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Running Deficits: Positives and Pitfalls
The FY2009 federal deficit swelled to $1.414 trillion, or nearly 10% of gross domestic product (GDP), due to the economic recession. The size of recent deficits has added to longstanding concerns regarding the federal government's long-term fiscal condition. However, deficit finance can serve as an important policy tool. This report discusses how deficit finance can help governments manage their economies and how large and persistent deficits can lead to severe economic problems
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Trends in Discretionary Spending
This report provides a graphical overview of historical trends in discretionary budget authority (BA) from FY1976 through FY2011, enacted levels for FY2012 spending, and the levels consistent with President Obama's proposals for FY2013 through FY2017. It also includes a background on functional categories and a section discussing historical spending trends
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Overview of the Federal Debt
The size of current and projected federal deficits and the accumulation of federal debt are central to current congressional deliberations regarding fiscal reforms. This report provides a broad overview of the federal debt, annual budget deficits, and debt service costs. Federal debt is the accumulated sum of unrepaid borrowing by the federal government over time. The total federal debt consists of debt held by the public and intragovernmental debt. Debt owed to the public represents borrowing from entities other than the federal government, and includes borrowing from state and local governments, foreign governments and investors, the Federal Reserve System, and foreign central banks, as well as private investors in the United States
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FY2011 Appropriations in Budgetary Context
This report compares the various funding levels that have been considered during the 112th Congress with H.R. 1473, a compromise reached just before the expiration on April 8 of the sixth continuing resolution (CR). H.R. 1473 provides discretionary budget authority to run the federal government for the remainder of FY2011, and includes both discretionary and mandatory spending reductions
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