Macroscopic and microscopic studies of electrical properties of very thin silicon dioxide subject to electrical stress

The electrical characteristics of various size tunnel switch diode devices, composed of Al/SiO2/n-Si/p+-Si layers, which operate with a range of parameters (such as current densities in excess of 104 A/cm2) that stress the oxide layer far beyond the levels used in typical thin oxide metal-oxide semiconductor research have been examined. It is found that the first time a large current and electric field are applied to the device, a "forming" process enhances transport through the oxide in the vicinity of the edges of the gate electrode, but the oxide still retains its integrity as a tunnel barrier. The device operation is relatively stable to stresses of greater than 107 C/cm2 areally averaged, time-integrated charge injection. Duplication and characterization of these modified oxide tunneling properties was attempted using scanning tunneling microscopy (STM) to stress and probe the oxide. Electrical stressing with the STM tip creates regions of reduced conductivity, possibly resulting from trapped charge in the oxide. Lateral variations in the conductivity of the unstressed oxide over regions roughly 20–50 nm across were also found

Ripken Products: A Case For Learning Activity-Based Costing

This case enables cost accounting students to understand two important and related topics: design flaws inherent in traditional absorption costing systems and the fundamentals of activity-based costing (ABC).  The focused approach requires only one class session to cover both topics.  Ripken Products, a fictional manufacturer, uses absorption costing to cost its products.  The company allocates manufacturing overhead using a budgeted manufacturing overhead rate based on direct labor cost.  The company president decides to discontinue a product with a reported zero gross profit.  A student intern suggests that the company could improve the accuracy of its costing for individual products if it assigned manufacturing overhead using activity-based costing.  Students learn to calculate product costs using ABC, and then they explore reasons for significant differences between ABC costs and the company’s reported costs.  Students discover the logical flaws of allocating overhead costs arbitrarily using traditional absorption costing methods.  They also learn why assigning overhead costs based on traceable consumption of resources leads to more accurate product costing

Visualizing Accounting Transaction Flows Into Financial Statements

Professors who teach the introductory accounting course should ask themselves: “What are the core concepts that I wish to have my non-majors remember if I meet them at their ten-year alumni class reunion?” There is a fundamental logic to financial accounting. This teaching note presents foundational accounting concepts in a manner that enables readers to understand this logic. In doing so, it answers the question posed above. The first half of the teaching note explains the purpose and elements of two primary financial reports: a balance sheet and an income statement. The second half presents the recording of several business transactions and traces their effect into a company’s balance sheet and income statement. Designed for use early in an introductory accounting course, the teaching note enables students to develop a strong conceptual understanding of financial accounting

Narrative preaching for millennials : inviting the next generation into God\u27s story

https://place.asburyseminary.edu/ecommonsatsdissertations/2552/thumbnail.jp

Liberty Company Bond Teaching Resource: Using A Zero-Coupon Bond To Clarify Bond Liability Accounting

Accounting for discounted and premium bond liabilities presents challenges for most students. Fortunately, committed educators can do something about the issue. In this teaching resource, the author presents an approach to simplify bond accounting concepts. Reversing the sequence that bond interest rates are introduced and explained can have a favorable effect on student comprehension. There are two interest rates associated with a bond: 1) a market rate and 2) a contract rate. When explaining bond fundamentals, it is natural to explain the features of a bond, including its contract interest rate, early in the discussion. This approach makes it difficult to explain later that the only effective interest rate on a bond is the market interest rate. Students must realize that the contract rate is not an effective interest rate. It is a percentage that is used to determine periodic cash payments - not interest expense. The Liberty Company Bond is a zero-coupon bond, similar to a U.S. Savings Bond that some students received as a graduation gift. Because the bond has only one non-zero interest rate, students are able to comprehend the nature and effect of both market and contract interest rates

The Economics of Selling Crop Residue Biomass for Cellulosic Ethanol Production at the Farm Level

A partial budget decision making framework has been developed to assist crop producers in analyzing the profitability of selling cellulosic biomass from their fields for ethanol production. A multidisciplinary approach is taken in assessing the agronomic and economic factors relevant to biomass contract sales decisions – with direct application made to western Great Plains cropping systems and enterprises. Within this framework the benefits of increased revenue from cellulosic biomass contract sales and potential government assistance payments are considered against possible decreased revenue from diminished crop yields resulting from less crop residue cover and subsequent soil moisture evaporation. Increased biomass harvesting and handling are also considered, as is the cost of replacing crop nutrients removed as part of biomass harvest operations. Examples of the profitability of cellulosic biomass contract sales in center pivot irrigated corn and non-irrigated wheat enterprises are shown.Resource /Energy Economics and Policy,

Cell death and degeneration in the symbiotic dinoflagellates of the coral Stylophora pistillata during bleaching

Rising sea temperatures are increasing the incidences of mass coral bleaching (the dissociation of the coral–algal symbiosis) and coral mortality. In this study, the effects of bleaching (induced by elevated light and temperature) on the condition of symbiotic dinoflagellates (Symbiodinium sp.) within the tissue of the hard coral Stylophora pistillata (Esper) were assessed using a suite of techniques. Bleaching of S. pistillata was accompanied by declines in the maximum potential quantum yield of photosynthesis (Fv/Fm, measured using pulse amplitude modulated [PAM] fluorometry), an increase in the number of Sytox-green-stained algae (indicating compromised algal membrane integrity and cell death), an increase in 2’,7’-dichlorodihydrofluroscein diacetate (H2DCFDA)- stained algae (indicating increased oxidative stress), as well as ultrastructural changes (vacuolisation, losses of chlorophyll, and an increase in accumulation bodies). Algae expelled from S. pistillata exhibited a complete disorganisation of cellular contents; expelled cells contained only amorphous material. In situ samples taken during a natural mass coral bleaching event on the Great Barrier Reef in February 2002 also revealed a high number of Sytox-labelled algae cells in symbio. Dinoflagellate\ud degeneration during bleaching seems to be similar to the changes resulting from senescence-phase cell death in cultured algae. These data support a role for oxidative stress in the mechanism of coral bleaching and highlight the importance of algal degeneration during the bleaching of a reef coral

Recruitment of Dok-R to the EGF receptor through its PTB domain is required for attenuation of Erk MAP kinase activation

AbstractDok (for downstream of tyrosine kinases) proteins are a newly identified family of docking molecules that are characterized by the presence of an amino-terminal pleckstrin homology (PH) domain, a central putative phosphotyrosine-binding (PTB) domain and numerous potential sites of tyrosine phosphorylation [1–6]. Here, we explore the potential role of the Dok family member Dok-R (also known as p56Dok2 or FRIP) in signaling pathways mediated by the epidermal growth factor (EGF) receptor. An intact PTB domain in Dok-R was critical for its association with two PTB-binding consensus sites on the EGF receptor and the PH domain further contributed to stable in vivo binding and tyrosine phosphorylation of Dok-R. Multiple sites on Dok-R were tyrosine-phosphorylated following EGF stimulation; phosphorylated Tyr276 and Tyr304 are proposed to dock the tandem Src homology 2 (SH2) domains of the p21Ras GTPase-activating protein rasGAP and Tyr351 mediates an association with the SH2 domain of the adapter protein Nck. Interestingly, we have found that Dok-R could attenuate EGF-stimulated mitogen-activated protein (MAP) kinase activation independently of its association with rasGAP. Together, these results suggest that Dok-R has an important role downstream of growth factor receptors as a potential negative regulator of signal transduction