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111.
Pithing cattle after captive bolt stunning, by thrusting a rod into the cranial cavity, causes violent muscular activity. The present observations have shown that this does not result in a rapid fall in the muscle pH similar to that occurring after electrical stimulation. The claim that pithing for a greater length than usual down the spinal cord causes marked enlargement of the spleen has not been substantiated. 相似文献
112.
Nanostructured mullite steam oxidation resistant coatings for silicon carbide deposited via atomic layer deposition
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Amanda L. Hoskins Aidan H. Coffey Charles B. Musgrave Alan W. Weimer 《Journal of the American Ceramic Society》2018,101(6):2493-2505
Oxidation resistant, thin, pinhole‐free, crystalline mullite coatings were deposited on zirconia and silicon carbide particles using atomic layer deposition (ALD). The composition of the films was confirmed with inductively coupled plasma optical emission spectroscopy (ICP OES), and the conformality and elemental dispersion of the films were characterized with transmission electron microscopy (TEM) and energy dispersive X‐ray spectroscopy (EDS), respectively. The films are deposited on the particle surface with a deposition rate of ~1 Å/cycle. The elemental concentration of aluminum relative to silicon in the film was determined to be 2.68:1 which agrees closely with the ratio of stable 3:2 mullite (2.88:1). A high‐temperature anneal for 5 hours at 1500°C was used to crystallize the films into the mullite phase. This work represents the first deposition of mullite films by ALD. The mullite and alumina‐coated particles were exposed to high‐temperature steam for 20 hours at 1000°C to assess the oxidation resistance of the films, which reduced the oxidation of silicon carbide by up to 62% relative to uncoated particles under these conditions. The activation energy of oxygen diffusion in the films was determined with density functional theory, and the computational results aligned well with the experimental outcomes. 相似文献
113.
Eng Gee Lim Jingchen Wang Gerry Juans Zhao Wang Mark Paul Leach Sanghyuk Lee Nipon Theera-Umpon 《Wireless Personal Communications》2018,98(4):3059-3070
This paper focuses on the development of a wearable radio frequency identification (RFID) antenna to be embedded on shirt collars or cuffs. Wearable RFID tags tend to be conformal, and are required to reasonably meet design specifications even when under deformation. A simple circular dipole structure was selected as the base design for the antenna. Operating in the ultra-high frequency band at 866 MHz and over an operating range of around 5 m, the antenna is versatile enough to be used for a number of applications such as the tagging of patients in a hospital or for workers on dangerous construction sites. The designs presented account for the complex input impedance generally observed in RFID systems and the final design employs an intricate spiral structure to accommodate longer wavelengths. This resulted in a compact portable antenna able to meet device specifications. 相似文献
114.
Richard W. Dawidek Thomas J. Hayward Ian T. Vidamour Thomas J. Broomhall Guru Venkat Mohanad Al Mamoori Aidan Mullen Stephan J. Kyle Paul W. Fry Nina-Juliane Steinke Joshaniel F. K. Cooper Francesco Maccherozzi Sarnjeet S. Dhesi Lucia Aballe Michael Foerster Jordi Prat Eleni Vasilaki Matthew O. A. Ellis Dan A. Allwood 《Advanced functional materials》2021,31(15):2008389
Emergent behaviors occur when simple interactions between a system's constituent elements produce properties that the individual elements do not exhibit in isolation. This article reports tunable emergent behaviors observed in domain wall (DW) populations of arrays of interconnected magnetic ring-shaped nanowires under an applied rotating magnetic field. DWs interact stochastically at ring junctions to create mechanisms of DW population loss and gain. These combine to give a dynamic, field-dependent equilibrium DW population that is a robust and emergent property of the array, despite highly varied local magnetic configurations. The magnetic ring arrays’ properties (e.g., non-linear behavior, “fading memory” to changes in field, fabrication repeatability, and scalability) suggest they are an interesting candidate system for realizing reservoir computing (RC), a form of neuromorphic computing, in hardware. By way of example, simulations of ring arrays performing RC approaches 100% success in classifying spoken digits for single speakers. 相似文献
115.
Mai T. Ngo Victoria R. Barnhouse Aidan E. Gilchrist Bhushan P. Mahadik Christine J. Hunter Joy N. Hensold Nathan Petrikas Brendan A. C. Harley 《Advanced functional materials》2021,31(51):2101541
Biomaterials that replicate patterns of microenvironmental signals from the stem cell niche offer the potential to refine platforms to regulate stem cell behavior. While significant emphasis has been placed on understanding the effects of biophysical and biochemical cues on stem cell fate, vascular-derived or angiocrine cues offer an important alternative signaling axis for biomaterial-based stem cell platforms. Elucidating dose-dependent relationships between angiocrine cues and stem cell fate are largely intractable in animal models and 2D cell cultures. In this study, microfluidic mixing devices are leveraged to generate 3D hydrogels containing lateral gradients in vascular density alongside murine hematopoietic stem cells (HSCs). Regional differences in vascular density can be generated via embossed gradients in cell, matrix, or growth factor density. HSCs co-cultured alongside vascular gradients reveal spatial patterns of HSC phenotype in response to angiocrine signals. Notably, decreased Akt signaling in high vessel density regions led to increased expansion of lineage-positive hematopoietic cells. This approach offers a combinatorial tool to rapidly screen a continuum of microenvironments with varying vascular, biophysical, and biochemical cues to reveal the influence of local angiocrine signals on HSC fate. 相似文献
116.
Christopher J. Matheus Aidan Boran Dominic Carr Rem W. Collier Barnard Kroon Olga Murdoch David Lillis Michael J. O'Grady Gregory M. P. O'Hare 《Computational Intelligence》2019,35(2):285-309
To accommodate the proliferation of heterogeneous network models and protocols, the use of semantic technologies to enable an abstract treatment of networks is proposed. Network adapters are employed to lift network specific data into a semantic representation. Semantic reasoning integrates the disparate network models and protocols into a common data model by making intelligent inferences from low‐level network and device details. Automatic discovery of new devices, monitoring of device state, and invocation of device actions in a generic fashion that is agnostic of network types is enabled. A prototype system called SNoMAC is described that employs the proposed approach operating over UPnP, TR‐069, and heterogeneous sensors. These sensors are integrated by means of a sensor middleware named SIXTH that augments the capabilities of SNoMAC to allow for intelligent management and configuration of a wide variety of sensor devices. A major benefit of this approach is that the addition of new models, protocols, or sensor types merely involves the development of a new network adapter based on an ontology. Additionally, the semantic representation of the network and associated data allows for a variety of client interfaces to facilitate human input to the management and monitoring of the system. 相似文献
117.
Peter Chapman Gem Stapleton Aidan Delaney 《Journal of Visual Languages and Computing》2013,24(5):327-349
Existing diagrammatic notations based on Euler diagrams are mostly limited in expressiveness to monadic first-order logic with an order predicate. The most expressive monadic diagrammatic notation is known as spider diagrams of order. A primary contribution of this paper is to develop and formalise a second-order diagrammatic logic, called second-order spider diagrams, extending spider diagrams of order. A motivation for this lies in the limited expressiveness of first-order logics. They are incapable of defining a variety of common properties, like ‘is even’, which are second-order definable. We show that second-order spider diagrams are at least as expressive as monadic second-order logic. This result is proved by giving a method for constructing a second-order spider diagram for any regular expression. Since monadic second-order logic sentences and regular expressions are equivalent in expressive power, this shows second-order spider diagrams can express any sentence of monadic second-order logic. 相似文献
118.
With the vision of "Internet as a computer", complex software-intensive systems running on the Internet, or the "Internetwares", can be also divided into multiple layers. Each layer has a different focus, implementation technique, and stakeholders. Monitoring and adaptation of such multilayer systems are challenging, because the mismatches and adaptations are interrelated across the layers. This interrelation makes it difficult to find out: 1) When a system change causes mismatches in one layer, how to identify all the cascaded mismatches on the other layers? 2) When an adaptation is performed at one layer, how to find out all the complementary adaptations required in other layers? This paper presents a model-based approach towards cross-layer monitoring and adaptation of multilayer systems. We provide standard meta-modelling languages for system experts to specify the concepts and constraints separately for each layer, as well as the relations among the concepts from different layers. Within each individual layer, we use run-time models to represent the system state specific to this layer, monitor the systems by evaluating model changes according to specified constraints, and support manual or semi-automated adaption by modifying the models. When a change happens in the run-time model for one layer, either caused by system changes or by the adaptation, we synchronize the models for other layers to identify cascaded mismatches and complementary adaptations across the layers. We illustrate the approach on a simulated crisis management system, and are using it on a number of ongoing projects. 相似文献
119.
The wear behaviour of flake graphite cast iron was correlated with the microstructural parameters of graphite volume fraction and flake size using a pin-on-ring specimen configuration. Pin specimens of cast iron were prepared under carefully controlled melting and casting conditions to provide microstructures with variation in either carbon content or flake size but with the same type A graphite structure and pearlitic matrix.Mild and severe modes of equilibrium wear were identified, the predominant effect of both microstructural parameters being in the severe wear regime. Decrease in flake size and increase in carbon content are detrimental to the wear behaviour resulting in a marked increase in the severe wear rate and a decrease in the mild-to-severe transition load. 相似文献
120.
Computational Visual Media - The concept of using multiple deep images, under a variety of different names, has been explored as a possible acceleration approach for finding ray-geometry... 相似文献