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Here we demonstrate how para-hydrogen can be used to prepare a two-spin system in an almost pure state which is suitable for implementing nuclear magnetic resonance (NMR) quantum computation. A 12ns laser pulse is used to initiate a chemical reaction involving pure para-hydrogn (the nuclear spin singlet of H2). The product, formed on the microsecond timescale, contains a hydrogen derived two-spin system with an effective spin-state purity of 0.916. To achieve a comparable result by direct cooling would require an unmanageable (in the liquid state) effective spin temperature of 6.4mK or an impractical magnetic field of 0.45MT at room temperature. The resulting spin state has an entanglement of formation of 0.822 and cannot be described by local hidden variable models., Comment: 4 pages including 2 figures. Changes from v.3 at request of referees. Now in press at Physical Review Letters

The conference includes papers describing theories and models of cell biology in microgravity and weightlessness; experimental research on cellular responses to altered gravity in plants and animals, natural and simulated; graviresponses in plants; gravitational effects in developmental biology; mechanisms of gravisensing; effects on animals and humans; and educational programs in Space Life Sciences.

The antiquity of biological sensitivity and response to gravity can be traced through the ubiquity of morphology, mechanisms, and cellular events in gravity sensing biological systems in the most diverse species of both plants and animals. Further, when we examine organisms at the cellular level to elucidate the molecular mechanism by which a gravitational signal is transduced into a biochemical response, the distinction between plants and animals becomes blurred.

An overview is presented of the concept and development of SSF and the unique opportunities offered by SSF to take advantage of the greater space, the increased power, and especially the long duration of the station for a cascade of innovative experiments in fundamental science. It is emphasized that this space environment will provide new dimensions for approaching some of the most challenging problems still facing modern biology.

Space may be, as some have called it, our last frontier. As such, it provides novel, even unique research opportunities. Plants are sure to figure significantly in these activities. The ability to manipulate the force of gravity from near zero to 1 g affords fresh opportunities to investigate gravity's physiological effects as well as a means of probing gravi- and phototropism, thigmo-morphogenesis, and other environmental effects in a state uncompromised by gravity. In this review we aim primarily to consider phenomenology, a goal that befits the state of our knowledge from space experiments. We intend to provide grist for future ground-based and space experiments and to reveal the potential for scientific discovery in this area.

Individual technical summaries of research projects of NASA's Space/Gravitational Biology Program are presented. The summaries for each project include a description of the research, a listing of the accomplishments, and an explanation of the significance of the accomplishments. Bibliographies for each project are also included.

The Life Sciences Division of the National Aeronautics and Space Administration (NASA) as part of its continuing assessment of its research program, convened a workshop on Developmental Biology to determine whether there are important scientific studies in this area which warrant continued or expanded NASA support. The workshop consisted of six panels, each of which focused on a single major phylogenetic group. The objectives of each panel were to determine whether gravity plays a role in the ontogeny of their subject group, to determine whether the microgravity of spaceflight can be used to help understand fundamental problems in developmental biology, to develop the rationale and hypotheses for conducting NASA-relevant research in development biology both on the ground and in space, and to identify any unique equipment and facilities that would be required to support both ground-based and spaceflight experiments.

Space flight provides a unique capability to gravitational research by providing an environment in which gravity can be manipulated below the Earth norm of 1 to a state comparable to weightlessness. Although space experiments with seeds and plants have been conducted for almost 25 years, we are only now entering an era that promises the capability of routinely conducting controlled plant experiments in space. Results from experiments with higher plants and seeds flown thus far in both manned and unmanned spacecraft from both the USA and USSR are briefly summarized. An overview of the current status of space biology experimentation as it relates to plants is presented and present and future opportunities to conduct plant experiments under space flight conditions are discussed.

Approximately 42 project summaries from NASA's Space Biology Program are presented. Emphasis is placed on gravitational effects on plant and animal life. The identification of gravity perception; the effects of weightlessness on genetic integrity, cellular differentiation, reproduction, development, growth, maturation, and senescence; and how gravity affects and controls physiology, morphology, and behavior of organisms are studied.

The requirements to and capabilities of a Space Station biological facility centrifuge are discussed on the basis of an assessment of the objectives and subjects of future microgravity biological experiments. It is argued that the facility should be capable of both acute and extended chronic exposure of test subjects and biological materials to altered-g loading. In addition, the experimental approaches and equipment for microgravity studies on a Space Station are outlined. Finally, the engineering requirements of such a centrifuge are examined, with consideration of radial gravity gradients, size, and physical access to animals.

The activities included five half days of presentations by space biology principal investigators, an evening of poster session presentations by research associates, and an afternoon session devoted to the Flight Experiments Program. Areas of discussion included the following: gravity receptor mechanisms; physiological effects of gravity, structural mass; fluid dynamics and metabolism; mechanisms of plant response; and the role of gravity in development.

Summaries of NASA's Space Biology Program projects are provided. The goals, objectives, accomplishments, and future plans of each project are described in this publication as individual technical summaries.

A discussion is presented of the research conducted under the auspices of the NASA Space Biology Program. The objectives of this Program include the determination of how gravity affects and how it has shaped life on earth, the use of gravity as a tool to investigate relevant biological questions, and obtaining an understanding of how near-weightlessness affects both plants and animals in order to enhance the capability to use and explore space. Several areas of current developmental research are discussed and the future focus of the Program is considered.

Documents cited represent research encompassing several disciplines of space biology: botany and plant pathology, physiology and biophysics, agricultural and environmental sciences, anatomy and embryology, cellular and comparative biology, horticulture and aerospace biology.

In Parker v. District of Columbia, the United States Court of Appeals for the District of Columbia Circuit ruled in a 2-1 decision that provisions of the D.C. Code that prohibit persons from keeping handguns in their home are unconstitutional in that they infringe upon the individual right to keep and bear arms. Upon making this determination, the court ruled that three elements of the D.C. gun control statutes were unconstitutional: (1) an effective prohibition on the registration of pistols (D.C. Code � 7-2502.2); (2) a prohibition on carrying a pistol, insofar as the prohibition could be construed to prohibit the keeping of a handgun in the home and preventing it from being moved throughout a person's home (D.C. Code � 22-4504); and (3) a statutory requirement that a registered firearm be kept unloaded and disassembled or bound by a trigger lock (D.C. Code � 7-2507.02). The Supreme Court of the United States granted a petition for certiorari on November 20, 2007, limited to the question of "[w]hether the following provisions, D.C. Code �� 7-2502.02(a)(4), 22-4504(a), and 7-2507.02, violate the Second Amendment rights of individuals who are not affiliated with any state-regulated militia, but who wish to keep handguns and other firearms for private use in their homes?" The Supreme Court of the United States heard oral arguments in the case, now called District of Columbia v. Heller, on March 18, 2008, and a decision is expected to be issued during the summer of 2008. Heller marks the first time in almost 70 years that the Supreme Court has agreed to consider the nature of the right conferred by the Second Amendment to the Constitution of the United States. This report provides an overview of prior judicial treatment of the Second Amendment, with a focus on the litigation in Heller and the potential impact of its outcome. [ABSTRACT FROM AUTHOR]

On January 29, 2008, President George W. Bush signed Executive Order 13,457, "Protecting American Taxpayers from Government Spending on Wasteful Earmarks." The order states that it is the policy of the federal government "to be judicious in the expenditure of taxpayer dollars." In order "[t]o ensure the proper use of taxpayer funds," the order provides that the number and cost of earmarks should be reduced, that their origin and purposes should be transparent; and that they should be included in the text of bills voted upon by Congress and presented to the President. For appropriations laws and other legislation enacted after the date of the order, it directs executive agencies not to commit, obligate, or expend funds on the basis of earmarks included in any non-statutory source, including requests in reports of committees of Congress or other congressional documents or communications on behalf of Members of Congress, or any other non-statutory source, except when required by law or when an agency itself has determined that a project, program, grant, or other transaction has merit under statutory criteria or other merit-based decision-making. In the context of the order, an "earmark" is defined as any [ABSTRACT FROM AUTHOR]

Presidential signing statements are official pronouncements issued by the President contemporaneously to the signing of a bill into law that, in addition to commenting on the law generally, have been used to forward the President's interpretation of the statutory language; to assert constitutional objections to the provisions contained therein; and, concordantly, to announce that the provisions of the law will be administered in a manner that comports with the Administration's conception of the President's constitutional prerogatives. While the history of presidential issuance of signing statements dates to the early 19th century, the practice has become the source of significant controversy in the modern era as Presidents have increasingly employed the statements to assert constitutional and legal objections to congressional enactments. President Reagan initiated this practice in earnest, transforming the signing statement into a mechanism for the assertion of presidential authority and intent. President Reagan issued 250 signing statements, 86 of which (34%) contained provisions objecting to one or more of the statutory provisions signed into law. President George H. W. Bush continued this practice, issuing 228 signing statements, 107 of which (47%) raised objections. President Clinton's conception of presidential power proved to be largely consonant with that of the preceding two administrations. In turn, President Clinton made aggressive use of the signing statement, issuing 381 statements, 70 of which (18%) raised constitutional or legal objections. President George W. Bush has continued this practice, issuing 152 signing statements, 118 of which (78%) contain some type of challenge or objection.... [ABSTRACT FROM AUTHOR]