Parametric investigation of single-expansion-ramp nozzles at Mach numbers from 0.60 to 1.20

An investigation was conducted in the Langley 16-Foot Transonic Tunnel to determine the effects of varying six nozzle geometric parameters on the internal and aeropropulsive performance characteristics of single-expansion-ramp nozzles. This investigation was conducted at Mach numbers from 0.60 to 1.20, nozzle pressure ratios from 1.5 to 12, and angles of attack of 0 deg +/- 6 deg. Maximum aeropropulsive performance at a particular Mach number was highly dependent on the operating nozzle pressure ratio. For example, as the nozzle upper ramp length or angle increased, some nozzles had higher performance at a Mach number of 0.90 because of the nozzle design pressure was the same as the operating pressure ratio. Thus, selection of the various nozzle geometric parameters should be based on the mission requirements of the aircraft. A combination of large upper ramp and large lower flap boattail angles produced greater nozzle drag coefficients at Mach number greater than 0.80, primarily from shock-induced separation on the lower flap of the nozzle. A static conditions, the convergent nozzle had high and nearly constant values of resultant thrust ratio over the entire range of nozzle pressure ratios tested. However, these nozzles had much lower aeropropulsive performance than the convergent-divergent nozzle at Mach number greater than 0.60

Controlled levels of protein modification through a chromatography-mediated bioconjugation.

Synthetically modified proteins are increasingly finding applications as well-defined scaffolds for materials. In practice it remains difficult to construct bioconjugates with precise levels of modification because of the limited number of repeated functional groups on proteins. This article describes a method to control the level of protein modification in cases where there exist multiple potential modification sites. A protein is first tagged with a handle using any of a variety of modification chemistries. This handle is used to isolate proteins with a particular number of modifications via affinity chromatography, and then the handle is elaborated with a desired moiety using an oxidative coupling reaction. This method results in a sample of protein with a well-defined number of modifications, and we find it particularly applicable to systems like protein homomultimers in which there is no way to discern between chemically identical subunits. We demonstrate the use of this method in the construction of a protein-templated light-harvesting mimic, a type of system which has historically been difficult to make in a well-defined manner

Adam Smith and the theory of punishment

A distinctive theory of punishment plays a central role in Smith's moral and legal theory. According to this theory, we regard the punishment of a crime as deserved only to the extent that an impartial spectator would go along with the actual or supposed resentment of the victim. The first part of this paper argues that Smith's theory deserves serious consideration and relates it to other theories such as utilitarianism and more orthodox forms of retributivism. The second part considers the objection that, because Smith's theory implies that punishment is justified only when there is some person or persons who is the victim of the crime, it cannot explain the many cases where punishment is imposed purely for the public good. It is argued that Smith's theory could be extended to cover such cases. The third part defends Smith's theory against the objection that, because it relies on our natural feelings, it cannot provide an adequate moral justification of punishment

Order Flow Cases: Jurisdiction, Preemption and Securities Laws

(Excerpt) Primary jurisdiction and preemption issues arise in securities class action litigation when alleged violations of state law arise from conduct that is either explicitly or implicitly regulated by the federal securities laws. These are two distinct theories: one is a matter of administrative law and judicial economy (primary jurisdiction); the other is a matter of constitutional law involving the Supremacy Clause (preemption). To date, there has not been extensive case law involving preemption and the federal securities laws (other than in the blue sky and tender offer areas) and there has been almost no case law on primary jurisdiction and the federal securities laws. This article discusses these issues in the context of the order flow cases. In the eight ongoing order flow cases pending in state courts in Illinois, Massachusetts, Minnesota and New York, the plaintiffs have challenged the practice of certain broker-dealers that make monetary and non-monetary payments to retail brokers, particularly discount brokers, for the purpose of inducing the retail brokers to send orders to the defendants for execution

Double Jeopardy Issues in the Financial Sector

(Excerpt) Double jeopardy issues arise regularly in the financial, banking and commodities industries where both civil and criminal statutes and penalties are used in successive prosecutions by federal and state governments to sanction the same conduct. Recent Supreme Court and federal court decisions have established new standards for determining when civil fines and other civil penalties constitute “punishment” for purposes of the double jeopardy clause of the Fifth Amendment. These decisions indicate that where a civil penalty imposed by a federal or state actor bears no “rational relation” to any actual damages caused, the penalty will be characterized as punishment for purposes of the double jeopardy clause

Welfare Reform: Lessons from New England

This article examines state welfare policy choices following the passage of the Personal Responsibility and Work Opportunity Reconciliation Act. Using data from national studies and an intensive study of policymaking in New England, the authors demonstrate that states have acted independently rather than uniformly in response to devolution. Because states did not respond as predicted, and for reasons that were not anticipated, scholars must develop new approaches to understanding state policymaking. This study argues that accounting for state policy choices requires an understanding of the context of policymaking. Conventional analyses of welfare reform have ignored the institutional structures through which policy is formulated and thus miss the most important determinant of choices: the actions of administrative officials. The lesson of welfare reform in New England is clear: administration matters

Impingement of Boundary-Reflected Disturbances Originating at the Nose of a Body of Revolution in the Langley Research Center 16-Foot Transonic Tunnel

An investigation has been conducted in the Langley 16-Foot Transonic Tunnel to determine boundary-reflected disturbance lengths at low supersonic Mach numbers in the octagonally shaped test section. A body of revolution that had a nose designed to produce a bow shock and flow field similar to that about the nose of a supersonic transport configuration was used. The impingement of reflected disturbances on the model was determined from static pressures measured on the surface of the model. Test variables included Mach number (0.90 to 1.25), model angle of attack (nominally -10, 0, and 10), and model roll angle

Magnetic meteorites and the early solar system

Today, the Earth generates a magnetic field through convection of the electrically conducting molten iron in its outer core. Core convection is governed by the thermal and chemical processes that operate deep within our planet; thus measurements of the intensity and direction of the magnetic field can provide insights into the thermochemical state of the Earth's interior. Crustal rocks can also record and preserve a memory of the field they experienced as they were forming. Paleomagnetic measurements can therefore provide records of ancient magnetic activity and, by extension, the internal conditions of our planet in the past (Tarduno et al. 2014). A combination of paleomagnetic and present-day magnetic measurements therefore allow us to study the long-term and large-scale evolution of our planet over billions of years; this method could also potentially allow us to predict how it may behave in the future