National Environmental Policy Act of 1969 (P.L. 91-190): Bibliography

This report provides a bibliography of resources outlining the legislative history of the National Environmental Policy Act of 1969

Control over phase separation and nucleation using a laser-tweezing potential

Control over the nucleation of new phases is highly desirable but elusive. Even though there is a long history of crystallization engineering by varying physicochemical parameters, controlling which polymorph crystallizes or whether a molecule crystallizes or forms an amorphous precipitate is still a poorly understood practice. Although there are now numerous examples of control using laser-induced nucleation, the absence of physical understanding is preventing progress. Here we show that the proximity of a liquid–liquid critical point or the corresponding binodal line can be used by a laser-tweezing potential to induce concentration gradients. A simple theoretical model shows that the stored electromagnetic energy of the laser beam produces a free-energy potential that forces phase separation or triggers the nucleation of a new phase. Experiments in a liquid mixture using a low-power laser diode confirm the effect. Phase separation and nucleation using a laser-tweezing potential explains the physics behind non-photochemical laser-induced nucleation and suggests new ways of manipulating matter

Role of "external facilitation" in implementation of research findings: a qualitative evaluation of facilitation experiences in the Veterans Health Administration

BACKGROUND: Facilitation has been identified in the literature as a potentially key component of successful implementation. It has not, however, either been well-defined or well-studied. Significant questions remain about the operational definition of facilitation and about the relationship of facilitation to other interventions, especially to other change agent roles when used in multi-faceted implementation projects. Researchers who are part of the Quality Enhancement Research Initiative (QUERI) are actively exploring various approaches and processes, including facilitation, to enable implementation of best practices in the Veterans Health Administration health care system – the largest integrated healthcare system in the United States. This paper describes a systematic, retrospective evaluation of implementation-related facilitation experiences within QUERI, a quality improvement program developed by the US Department of Veterans Affairs. METHODS: A post-hoc evaluation was conducted through a series of semi-structured interviews to examine the concept of facilitation across several multi-site QUERI implementation studies. The interview process is based on a technique developed in the field of education, which systematically enhances learning through experience by stimulating recall and reflection regarding past complex activities. An iterative content analysis approach relative to a set of conceptually-based interview questions was used for data analysis. FINDINGS: Findings suggest that facilitation, within an implementation study initiated by a central change agency, is a deliberate and valued process of interactive problem solving and support that occurs in the context of a recognized need for improvement and a supportive interpersonal relationship. Facilitation was described primarily as a distinct role with a number of potentially crucial behaviors and activities. Data further suggest that external facilitators were likely to use or integrate other implementation interventions, while performing this problem-solving and supportive role. PRELIMINARY CONCLUSIONS: This evaluation provides evidence to suggest that facilitation could be considered a distinct implementation intervention, just as audit and feedback, educational outreach, or similar methods are considered to be discrete interventions. As such, facilitation should be well-defined and explicitly evaluated for its perceived usefulness within multi-intervention implementation projects. Additionally, researchers should better define the specific contribution of facilitation to the success of implementation in different types of projects, different types of sites, and with evidence and innovations of varying levels of strength and complexity

Soluble Rhesus Lymphocryptovirus gp350 Protects against Infection and Reduces Viral Loads in Animals that Become Infected with Virus after Challenge

Epstein-Barr virus (EBV) is a human lymphocryptovirus that is associated with several malignancies. Elevated EBV DNA in the blood is observed in transplant recipients prior to, and at the time of post-transplant lymphoproliferative disease; thus, a vaccine that either prevents EBV infection or lowers the viral load might reduce certain EBV malignancies. Two major approaches have been suggested for an EBV vaccine- immunization with either EBV glycoprotein 350 (gp350) or EBV latency proteins (e.g. EBV nuclear antigens [EBNAs]). No comparative trials, however, have been performed. Rhesus lymphocryptovirus (LCV) encodes a homolog for each gene in EBV and infection of monkeys reproduces the clinical, immunologic, and virologic features of both acute and latent EBV infection. We vaccinated rhesus monkeys at 0, 4 and 12 weeks with (a) soluble rhesus LCV gp350, (b) virus-like replicon particles (VRPs) expressing rhesus LCV gp350, (c) VRPs expressing rhesus LCV gp350, EBNA-3A, and EBNA-3B, or (d) PBS. Animals vaccinated with soluble gp350 produced higher levels of antibody to the glycoprotein than those vaccinated with VRPs expressing gp350. Animals vaccinated with VRPs expressing EBNA-3A and EBNA-3B developed LCV-specific CD4 and CD8 T cell immunity to these proteins, while VRPs expressing gp350 did not induce detectable T cell immunity to gp350. After challenge with rhesus LCV, animals vaccinated with soluble rhesus LCV gp350 had the best level of protection against infection based on seroconversion, viral DNA, and viral RNA in the blood after challenge. Surprisingly, animals vaccinated with gp350 that became infected had the lowest LCV DNA loads in the blood at 23 months after challenge. These studies indicate that gp350 is critical for both protection against infection with rhesus LCV and for reducing the viral load in animals that become infected after challenge. Our results suggest that additional trials with soluble EBV gp350 alone, or in combination with other EBV proteins, should be considered to reduce EBV infection or virus-associated malignancies in humans

Characterisation of time-dependent mechanical behaviour of trabecular bone and its constituents

Trabecular bone is a porous composite material which consists of a mineral phase (mainly hydroxyapatite), organic phase (mostly type I collagen) and water assembled into a complex, hierarchical structure. In biomechanical modelling, its mechanical response to loads is generally assumed to be instantaneous, i.e. it is treated as a time-independent material. It is, however, recognised that the response of trabecular bone to loads is time-dependent. Study of this time-dependent behaviour is important in several contexts such as: to understand energy dissipation ability of bone; to understand the age-related non-traumatic fractures; to predict implant loosening due to cyclic loading; to understand progressive vertebral deformity; and for pre-clinical evaluation of total joint replacement. To investigate time-dependent behaviour, bovine trabecular bone samples were subjected to compressive loading, creep, unloading and recovery at multiple load levels (corresponding to apparent strain of 2,000-25,000 με). The results show that: the time-dependent behaviour of trabecular bone comprises of both recoverable and irrecoverable strains; the strain response is nonlinearly related to applied load levels; and the response is associated with bone volume fraction. It was found that bone with low porosity demonstrates elastic stiffening followed by elastic softening, while elastic softening is demonstrated by porous bone at relatively low loads. Linear, nonlinear viscoelastic and nonlinear viscoelastic-viscoplastic constitutive models were developed to predict trabecular bone’s time-dependent behaviour. Nonlinear viscoelastic constitutive model was found to predict the recovery behaviour well, while nonlinear viscoelastic-viscoplastic model predicts the full creep-recovery behaviour reasonably well. Depending on the requirements all these models can be used to incorporate time-dependent behaviour in finite element models. To evaluate the contribution of the key constituents of trabecular bone and its microstructure, tests were conducted on demineralised and deproteinised samples. Reversed cyclic loading experiments (tension to compression) were conducted on demineralised trabecular bone samples. It was found that demineralised bone exhibits asymmetric mechanical response - elastic stiffening in tension and softening in compression. This tension to compression transition was found to be smooth. Tensile multiple-load-creep-unload-recovery experiments on demineralised trabecular samples show irrecoverable strain (or residual strain) even at the low stress levels. Demineralised trabecular bone samples demonstrate elastic stiffening with increasing load levels in tension, and their time-dependent behaviour is nonlinear with respect to applied loads . Nonlinear viscoelastic constitutive model was developed which can predict its recovery behaviour well. Experiments on deproteinised samples showed that their modulus and strength are reasonably well related to bone volume fraction. The study considers an application of time-dependent behaviour of trabecular bone. Time-dependent properties are assigned to trabecular bone in a bone-screw system, in which the screw is subjected to cyclic loading. It is found that separation between bone and the screw at the interface can increase with increasing number of cycles which can accentuate loosening. The relative larger deformation occurs when this system to be loaded at the higher loading frequency. The deformation at the bone-screw interface is related to trabecular bone’s bone volume fraction; screws in a more porous bone are at a higher risk of loosening

Arable weed seeds as indicators of regional cereal provenance: a case study from Iron Age and Roman central-southern Britain

The ability to provenance crop remains from archaeological sites remains an outstanding research question in archaeology. Archaeobotanists have previously identified the movement of cereals on the basis of regional variations in the presence of cereal grain, chaff and weed seeds (the consumer–producer debate), and weed seeds indicative of certain soil types, principally at Danebury hillfort. Whilst the former approach has been heavily criticised over the last decade, the qualitative methods of the latter have not been evaluated. The first interregional trade in cereals in Britain is currently dated to the Iron Age hillfort societies of the mid 1st millennium bc. Several centuries later, the development of urban settlements in the Late Iron Age and Roman period resulted in populations reliant on food which was produced elsewhere. Using the case study of central-southern Britain, centred on the oppidum (large fortified settlement) and civitas capital of Silchester, this paper presents the first regional quantitative analysis of arable weed seeds in order to identify the origin of the cereals consumed there. Analysis of the weed seeds which were present with the fine sieve by-products of the glume wheat Triticum spelta (spelt) shows that the weed floras of samples from diverse geological areas can be separated on the basis of the soil requirements of individual taxa. A preliminary finding is that, rather than being supplied with cereals from the wider landscape of the chalk region of the Hampshire Downs, the crops were grown close to Late Iron Age Silchester. The method presented here requires further high quality samples to evaluate this conclusion and other instances of cereal movement in the past