Normal aging and Alzheimer's disease : hippocampal and episodic memory differences

Alzheimer’s Disease (AD) and normal aging (NA) are characterized by structural brain changes as well as cognitive changes that appear over the lifespan. The hippocampus is an area susceptible to early atrophy in both AD and NA; however the differential causes of atrophy are not entirely clear. Hippocampal volume loss in AD is attributed to neuronal death due to underlying pathology. AD often is diagnosed years after the onset of pathology and subsequent atrophy. NA is a continuation of cognitive decline that does not become dementia. Episodic memory (EM) is processed within the hippocampus and is one of the first systems to show deficits in conjunction with both patterns of aging. This review focuses on hippocampal volume loss and EM decline in NA and AD.Communication Sciences and Disorder

Ceramic-ceramic shell tile thermal protection system and method thereof

A ceramic reusable, externally applied composite thermal protection system (TPS) is proposed. The system functions by utilizing a ceramic/ceramic upper shell structure which effectively separates its primary functions as a thermal insulator and as a load carrier to transmit loads to the cold structure. The composite tile system also prevents impact damage to the atmospheric entry vehicle thermal protection system. The composite tile comprises a structurally strong upper ceramic/ceramic shell manufactured from ceramic fibers and ceramic matrix meeting the thermal and structural requirements of a tile used on a re-entry aerospace vehicle. In addition, a lightweight high temperature ceramic lower temperature base tile is used. The upper shell and lower tile are attached by means effective to withstand the extreme temperatures (3000 to 3200F) and stress conditions. The composite tile may include one or more layers of variable density rigid or flexible thermal insulation. The assembly of the overall tile is facilitated by two or more locking mechanisms on opposing sides of the overall tile assembly. The assembly may occur subsequent to the installation of the lower shell tile on the spacecraft structural skin

History of state aid furnished public school systems of Massachusetts.

Thesis (M.A.)--Boston Universit

On the Effectiveness of Agricultural Land-Use Controls

Land resources are a valuable resource in the economic system. There exists considerable controversy surrounding the allocation of land into the competing land uses. At the heart of this controversy are agricultural land resources. The purpose of this paper is to investigate, first theoretically and second empirically, the effectiveness of controls placed on land use to keep land in agricultural production. A theoretical conclusion is reached as to whether the free market or 1 and-use controls allocate land resources more efficiently. An empirical model is formulated to explain changes in the quantity of agricultural land as a function of several hypothesized explanatory variables, one of which is a land-control dummy variable to measure the effectiveness of agricultural land-use controls. The general conclusion reached is that for the most part, the controls have been ineffective. Where they have been effective in influencing land-use allocation, questions still exist concerning the cost imposed upon society from the control influenced land allocation

Toughened uni-piece fibrous insulation

A porous body of fibrous, low density silica-based insulation material is at least in part impregnated with a reactive boron oxide containing borosilicate glass frit, a silicon tetraboride fluxing agent and a molybdenum silicide emittance agent. The glass frit, fluxing agent and emittance agent are separately milled to reduce their particle size, then mixed together to produce a slurry in ethanol. The slurry is then applied to the insulation material and sintered to produce the porous body

Towards a model of factors affecting resistance to using multi-method authentication systems in higher-education environments

Over the course of history, different means of object as well as person identification and verification have evolved for user authentication. In recent years, a new concern has emerged regarding the accuracy of authentication and of protection of personal identifying information (PII), because previous information systems (IS) misuses have resulted in significant financial loss. Such losses have escalated more noticeably because of identity-theft incidents due to breaches of PII within multiple public-access environments, such asinstitutions of higher-education. Although the use of various biometric and radio frequency identification (RFID) technologies is expanding, resistance to using these technologies remains an issue. As such, in this research-in-progress paper, we outline a predictive study to assess the contribution of campus students’ perceptions of the importance of protecting their PII, noted as Perceived Value of Organizational Protection of PII (PVOP), authentication complexity (AC), and invasion of privacy (IOP) on their resistance to using multi-method authentication systems (RMS) in higher-education environments. In this work-in-progress study, we seek to better understand the theoretical foundations for the effect of students’ perceptions on their resistance to using multi-method authentication systems (RMS) in higher-education environments and uncover key constructs that may significantly contribute to such resistance. A quasiexperiment is proposed including clearly identified procedures and data analyses

Hypervelocity impact - A series solution. Part II - Spherical flow

Series solution to describe hydrodynamic phase flow field during hypervelocity impact of compressible penetrating particle into ideal fluid - Hugoniot equation of stat

Leadership practices and indicators of quality, connected through internal evaluation processes in the New Zealand ECE sector

The last few years has seen a significant increase in the attention paid to leadership in the New Zealand early childhood education (ECE) sector, particularly in guiding documents. While these provide greater clarity than previously on expectations around leadership practice, a greater understanding of what leadership means and how it is implemented in different contexts is still needed. This article is based on a study exploring how educational leadership is practised through internal evaluation processes in New Zealand ECE services, and how these practices support the professional capabilities and capacities of teachers. Previous research has highlighted that a practice approach to leadership removes the focus on the individual leader and allows leadership to emerge from collective action. The objectives of this research study were: to develop a better understanding of how educational leadership is practised through internal evaluation processes; explore what challenges or enables teachers to become involved and practise educational leadership through internal evaluation processes; and to understand how services monitor the impact of changes on teaching practice, made as a result of an internal evaluation. This qualitative research, which took the form of an interpretive case study, was framed around a single case design with multiple units of analysis. Data were gathered from three participating ECE services through interviews, focus groups and observations, and drew on the perspectives of both teachers and positional leaders. A reflexive thematic data analysis approach was employed, and four key themes were developed: identification with leadership; supportive workplace culture; continuous improvement; and effective leadership practices in ECE services. Seven effective leadership practices were also identified: relational leadership; creating the conditions for teamwork; engagement; knowledge expertise and sharing opinions; shared decision making; facilitating and guiding and accountability and organisation. This article contributes to our further understanding of educational leadership practices in New Zealand ECE services

Resource Study of Large-Scale Electric Water Heater Aggregation

Residential-scale distributed energy assets, like residential electric water heaters, individually present a negligible load to the power grid. When aggregated, however, these assets can impart significant effects within a balancing area; they may be dispatched en masse to provide grid services. An aggregation of water heaters may be controlled to assume generator-like functions with the ability to effectively “decrement power” through dispatch of load. This resource study examines the capabilities of a 10,000 unit water heater aggregation by subjecting the aggregate to dispatch requests of various size and duration, then analyzing how the aggregate responds to and recovers from these requests. Results show that a large-scale aggregation of electric water heaters may effectively decrement power on the scale of megawatts when the dispatch request size and duration are appropriately considered