211 research outputs found
Onset of creep stress measurement of metallic materials interim report
Onset of creep stress measured for metallic materials subjected to constant loads at elevated temperatures - tension testin
Onset of creep stress measurements in metallic materials. Creep test machine construction and operation
Construction and operation of machine for measuring creep deformations in threshold regions of metallic material
Floral Provisioning for Wild Bee Pollinators in Winter Squash and Muskmelon
When we talk about pollination, the image that comes to mind most frequently is the honeybee. Honeybees do provide the majority of pollination services in our current agricultural system. However, there are wild bees pollinating flowering crops at the same time and these bees are capable of providing a significant portion of the pollination services required of many crops. In fact, in some instances, wild bees may be better pollinators than managed honeybees
Electromagnetic interference of GSM mobile phones with the implantable deep brain stimulator, ITREL-III
BACKGROUND: The purpose was to investigate mobile phone interference with implantable deep brain stimulators by means of 10 different 900 Mega Hertz (MHz) and 10 different 1800 MHz GSM (Global System for Mobile Communications) mobile phones. METHODS: All tests were performed in vitro using a phantom especially developed for testing with deep brain stimulators. The phantom was filled with liquid phantom materials simulating brain and muscle tissue. All examinations were carried out inside an anechoic chamber on two implants of the same type of deep brain stimulator: ITREL-III from Medtronic Inc., USA. RESULTS: Despite a maximum transmitted peak power of mobile phones of 1 Watt (W) at 1800 MHz and 2 W at 900 MHz respectively, no influence on the ITREL-III was found. Neither the shape of the pulse form changed nor did single pulses fail. Tests with increased transmitted power using CW signals and broadband dipoles have shown that inhibition of the ITREL-III occurs at frequency dependent power levels which are below the emissions of GSM mobile phones. The ITREL-III is essentially more sensitive at 1800 MHz than at 900 MHz. Particularly the frequency range around 1500 MHz shows a very low interference threshold. CONCLUSION: These investigations do not indicate a direct risk for ITREL-III patients using the tested GSM phones. Based on the interference levels found with CW signals, which are below the mobile phone emissions, we recommend similar precautions as for patients with cardiac pacemakers: 1. The phone should be used at the ear at the opposite side of the implant and 2. The patient should avoid carrying the phone close to the implant
The Effect of Goal Setting and Student Self-Reflection on Motivation and On Task Behavior in the Upper Elementary Public Montessori Environment
The purpose of this action research project was to study the effects of goal-setting and self-reflection on the intrinsic motivation and on task behavior of students in an upper level (ages 9-12) public Montessori classroom. The project used multiple data sources to better understand the impact of goal-setting and self-reflection on student academic achievement, prosocial behavior, and emotional wellbeing. Teacher-made rating scales and self-reflection prompts were used to determine student outlook on completion of their goals while semi-structured student interviews, given at the beginning, middle, and end of the project, gave insight into student perceptions of goal-setting benefits. After analyzing the results of the data, it was found that weekly short term and long range goal-setting can have a positive impact on student achievement, prosocial behavior, and emotional wellbeing
Temperature measurement on neurological pulse generators during MR scans
According to manufacturers of both magnetic resonance imaging (MRI) machines, and implantable neurological pulse generators (IPGs), MRI is contraindicated for patients with IPGs. A major argument for this restriction is the risk to induce heat in the leads due to the electromagnetic field, which could be dangerous for the surrounding brain parenchyma. The temperature change on the surface of the case of an ITREL-III (Medtronic Inc., Minneapolis, MN) and the lead tip during MRI was determined. An anatomical realistic and a cubic phantom, filled with phantom material mimicking human tissue, and a typical lead configuration were used to imitate a patient who carries an IPG for deep brain stimulation. The measurements were performed in a 1.5 T and a 3.0 T MRI. 2.1°C temperature increases at the lead tip uncovered the lead tip as the most critical part concerning heating problems in IPGs. Temperature increases in other locations were low compared to the one at the lead tip. The measured temperature increase of 2.1°C can not be considered as harmful to the patient. Comparison with the results of other studies revealed the avoidance of loops as a practical method to reduce heating during MRI procedures
Disaster risk management and business education: the case of small and medium enterprises
Predictability of thermo-lesions using electrodes for deep brain stimulation - an in vitro study
<p>Abstract</p> <p>Background</p> <p>Typically, electrodes for Deep Brain Stimulation (DBS) are used for chronic stimulation. However, there are conditions where this therapy has to be discontinued. In such cases using the DBS electrodes as a tool for thermo-lesioning (coagulation) could be used for an alternative treatment. The aim of this study was to determine if it is possible to generate coagula with a predictable geometry and to define their dimensions as a function of power and time in an in vitro model (egg white at room temperature). Furthermore, we tested if repetitive (cumulative) coagulation has an impact on the overall form and size of the clot.</p> <p>Findings</p> <p>Coagulation-growth was achieved as a function of power and duration of coagulation; reproducible well-formed thermocoagulations could be achieved. When using two adjacent electrodes a power range between 1.25 Watt and 2.00 Watt resulted in homogenous ovoid coagula. After two minutes of coagulation the clots reached a maximum in size and further growth could not be achieved. It was also possible to increase the size of a preformed clot by repetitive coagulation either by increasing the power level or the duration of the coagulation process.</p> <p>Conclusions</p> <p>We could show that it is possible to obtain predictable coagula in-vitro when using DBS electrodes for thermocoagulation even though they have not been developed for that specific purpose. However, until in-vivo safety and efficacy of DBS electrodes for ablation purposes is properly assessed, only approved electrodes should be used for brain ablation.</p
Disasters as Opportunity for Change: Tsunami Recovery and Energy Transition in Japan
Disasters may offer a window of opportunity, in which extraordinary circumstances create momentum for positive social change. While this potential is popularized through the concept of “building back better,” few studies have examined quantitatively the processes and drivers of broader social change in a post-disaster context. Using renewable energy transition (specifically, solar photovoltaic diffusion) as one measure of building back better, this study explores how pre-and post- disaster contexts, capacities, and policies affected recovery outcomes of 30 coastal communities nearly 5 years following the Great East Japan earthquake, tsunami, and nuclear disaster (Tohoku disaster). Our study shows that the disaster-affected communities adopted significantly more solar power than the rest of Japan following the introduction of the country's Feed-in-Tariff (FIT) system in 2012. The communities examined are highly diverse in their solar energy adoption as of 2015, and regression analysis was conducted to explain differences in overall solar energy diffusion as well as in adoption of very large scale mega-solar projects. The dynamic relationship between physical damage and subsequent solar adoption was found to be nonlinear, as was the relationship between degree of household relocation and solar energy adoption. Differences in communities’ mega-solar adoption were also explained by the variability in hazard zone designation and extent of physical damage. These findings suggest that a disaster may serve as an opportunity for positive community change when immediate impact (or the level of change involved in a reconstruction process) is high enough but not overwhelming. Overall, this study finds potentially complex relationships
Usability of therapy controllers in elderly patients with deep brain stimulation
<p>Abstract</p> <p>Background</p> <p>Technical devices are becoming more prevalent in society and also in medical care. Older adults need more support to learn new technologies than younger subjects. So far, no research has been done on the usability of patient controllers in deep brain stimulation in an elderly population. The aim of the study was to investigate the factors influencing the performance of elderly DBS patients with respect to usability aspects of Medtronic Access therapy controllers.</p> <p>Methods</p> <p>Time, mistakes and frequency of use of the controller were compared in 41 elderly DBS patients who prior to the study had already owned a therapy controller for more than six years. One group (n = 20, mean age = 66.4 years) was watching an instructional video and then completed practical assignments on a model implantable pulse generator (IPG). The other group (n = 21, mean age = 65.9 years) completed the tasks without having seen the video before. Any errors that patients made were documented and also corrected so that all of them received hands-on training. After six months all patients were re-evaluated on the dummy IPG in order to compare the effects of hands-on alone vs. video-based training combined with hands-on.</p> <p>Results</p> <p>The group that had seen the video before significantly outperformed the control group at both assessments with respect to number of errors. Both groups performed faster after six months compared to baseline and tend to use the controller more often than at baseline.</p> <p>Conclusion</p> <p>Our results indicate that elderly DBS patients who have been using the controller for several years still have various difficulties in operating the device. However, we also showed that age-specific training may improve the performance in older adults. In general, the design of DBS patient controllers should focus on the specific needs of the end-users. But as changes to medical devices take a long time to be implemented, video instructions with age-specific content plus hands-on training may improve learning for older adults.</p
- …