Medical technology development: limiting regulation

The medical technology industry is one of the most innovative sectors of the US economy. The paper considers how the US federal government, in a variety of roles as promoter, protector and payer, is involved in every stage of the innovative process for medical technology. It discusses the influence of government policies on medical innovation     

Cognitive impenetrability of memory for orientation.

This research produced evidence that an aspect of visual long-term memory—memory for lateral orientation of pictures—is constrained by a viewer-centered or egocentric reference frame. Subjects in Experiment 1 verbally encoded and then verbally recalled the locations of objects within scenic pictures. Recall of locations in terms of left-right directions (using a viewer-centered frame) exceeded recall of locations in terms of relative proximities to features of the room (using an environmental frame), even if the relative proximities had been verbalized at input. Subjects in Experiment 2 viewed half of a list of pictures directly and the remainder, reflected in a mirror. They then took a test in which they classified old pictures—all viewed directly— as "same-orientation" or "reversed." Performance was much better with a viewer-centered definition of same orientation (Does the picture appear the same way around?) than with an environmental definition (Is the picture the same way around on the screen?), even with forewarning of an environmental orientation test. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Management of the patient with minor traumatic brain injury

Staff in the accident and emergency department and critical care unit are often confronted with patients who have sustained life-threatening injuries. In such situations the symptoms of a minor traumatic brain injury (MTBI) may be missed. It is important that, when the physical symptoms begin to subside, nurses are aware of the symptoms of MTBI and respond accordingly. A post-concussion syndrome may develop 2 weeks to 2 months after a MTBI. This syndrome can affect the patient's ability to perform the usual activities of living. This article defines MTBI, describes the symptoms encountered in patients with MTBI, and outlines the pathophysiology, clinical findings, treatment and nursing interventions.     

Expression and localization of membrane type 1 matrix metalloproteinase in tooth tissues

Matrix metalloproteinases (MMPs) have been detected in forming dental enamel and are thought to play an important role during enamel biomineralization. Membrane-type 1 matrix metalloproteinase (MT1-MMP) is a membrane bound member of the MMP gene family that has previously been shown to be expressed by cells associated with bone and cartilage formation (osteoclasts, osteoblasts and chondrocytes). Thus, we asked if MT1-MMP was also expressed by the cells responsible for the formation of enamel and dentin. A porcine MT1-MMP cDNA composed of 3284 bp was isolated from an enamel organ-specific cDNA library. Multiple tissue Northern blot analysis revealed that the MT1-MMP message was expressed highly in the enamel organ and pulp organ when compared to the expression levels observed in other non-mineralizing tissues. Northern blot analysis of stage-specific enamel organs (early secretory, late secretory, or maturation stage) and their corresponding pulp organs revealed that MT1-MMP expression increased as the dentin matured. In the enamel organs, however, the MT1-MMP message level became reduced only during the late secretory stage. Immunohistochemical analysis showed that MT1-MMP was present on the surface of the cells (ameloblasts and odontoblasts) responsible for dentin and enamel formation. Thus, MT1-MMP is highly expressed in developing tooth tissues and may play a role in the biomineralization of enamel and dentin.     

Efficacy of silicone punctal plugs as adjuncts to topical pharmacotherapy of glaucoma--a pilot study. Punctal Plugs in Glaucoma Study Group

BACKGROUND: The concept of enhancing the ocular hypotensive effects of topical antiglaucoma medications by impeding lacrimal drainage of medication has been insufficiently studied. This investigation sought to evaluate the effect of bilateral inferior punctal occlusion using silicone punctal plugs on the ocular hypotensive effect of topically applied timolol. METHODS: A randomized, double-masked, cross-over clinical trial was conducted, comparing the ocular hypotensive effect of timolol maleate 0.25 percent, both with and without occlusion of the inferior punctum with the Freeman silicone punctal plug. Following a 2-week washout of topical medication, 17 subjects with early primary open-angle glaucoma or ocular hypertension received one drop of timolol 0.25 percent in each eye with or without punctal plugs in place. Blood pressure, resting pulse rate, and intraocular pressure were measured both before timolol instillation and at intervals of 1, 2, 4, 8, and 12 hours following drop instillation. Following a 2-week washout period, the subjects were evaluated with the alternative treatment. RESULTS: There was no statistically significant difference (p = 0.648) in IOP levels between treatment groups. CONCLUSIONS: This pilot suggests that need for a longer-term study with larger numbers of subjects to evaluate the potential role of silicone punctal plugs to enhance the ocular bioavailability of topically applied antiglaucoma medications.     

Ractions of SiC with H2/H2O/Ar Mixtures at 1300°C

The reactions of a sintered α-SiC with 5% H₂/H₂O/Ar at 1300°C were studied. Thermomchemical modeling indicates that three reaction regions are expected, depending on the initial water vapor or equivalently oxygen content of the gas stream. A high oxygen content ( P (O₂) > 10⁻²² atm) leads to a SiO₂ formation. This generally forms as a protective film and limits consumption of the SiC (passive oxidation). An intermediate oxygen content (10⁻²² atm > P (O₂) > 10⁻²⁶ atm) leads to SiO and CO formation. These gaseous products can lead to rapid consumption of the SiC (active oxidation). Thermogravimetric studies in this intermediate region gave reaction rates which appear to be controlled by H₂O gas-phase transport to the sample and reacted microstructures showed extensive grain-boundary attack in this region. Finally, a very low oxygen content ( P (O₂) < 10⁻²⁶ atm) is thermochemically predicted to lead to selective removal of carbon and formation of free silicon. Experimentally low weight losses and iron silicides are observed in this region. The iron silicides are attributed to reaction of free silicon and iron impurities in the system.     

Implementation of Envelope Analysis on a Wireless Condition Monitoring System for Bearing Fault Diagnosis

 Envelope analysis is an effective method for characterizing impulsive vibrations in wired condition monitoring (CM) systems. This paper depicts the implementation of envelope analysis on a wireless sensor node for obtaining a more convenient and reliable CM system. To maintain CM performances under the constraints of resources available in the cost effective Zigbee based wireless sensor network (WSN), a low cost cortex-M4F microcontroller is employed as the core processor to implement the envelope analysis algorithm on the sensor node. The on-chip 12 bit analog-to-digital converter (ADC) working at 10 kHz sampling rate is adopted to acquire vibration signals measured by a wide frequency band piezoelectric accelerometer. The data processing flow inside the processor is optimized to satisfy the large memory usage in implementing fast Fourier transform (FFT) and Hilbert transform (HT). Thus, the envelope spectrum can be computed from a data frame of 2048 points to achieve a frequency resolution acceptable for identifying the characteristic frequencies of different bearing faults. Experimental evaluation results show that the embedded envelope analysis algorithm can successfully diagnose the simulated bearing faults and the data transmission throughput can be reduced by at least 95% per frame compared with that of the raw data, allowing a large number of sensor nodes to be deployed in the network for real time monitoring.     

Digital design and time on device; how aesthetic experience can help to illuminate the psychological impact of living in a digital culture

ABSTRACT

Aesthetic techniques are increasingly used by marketeers to create enticing digital products. In this paper, I work with the aesthetic experiences of one audience group to consider the psychological impact of living in a culture where digital devices are deliberately designed to influence behaviour. I argue that aesthetic encounters can help with understanding the impact of the interplay between visual stimulus, affect and digital culture, in ways that may support situated understandings of mental distress in a digital age. I show how audiences respond to the artist-led research project Are We All Addicts Now? arguing that they generate ideas connected to submersion and being overwhelmed as a means of reporting on their own personal experiences of living in a digital culture that seeks to influence behaviour. The findings may have value for designers, curators and artists invested in understanding the experiential impact of digital devices.     

Depolarization measurements of an integrating sphere

Mueller-matrix polarimetry performed in the visible and near IR indicates that an integrating sphere acts as an ideal depolarizer to the 0.5% accuracy of the polarimeter. The integrating sphere emits unpolarized light regardless of the incident polarization state.