A demographic and epidemiological study of a Mexican chiropractic college public clinic

<p>Abstract</p> <p>Background</p> <p>Descriptive studies of chiropractic patients are not new, several have been performed in the U.S., Australia, Canada, and Europe. None have been performed in a Latin American country. The purpose of this study is to describe the patients who visited a Mexican chiropractic college public clinic with respect to demographics and clinical characteristics.</p> <p>Methods</p> <p>This study was reviewed and approved by the IRB of Parker College of Chiropractic and the Universidad Estatal del Valle de Ecatepec (UNEVE). Five hundred patient files from the UNEVE public clinic from May 2005 to May 2007 were selected from an approximate total number of 3,700. Information was collected for demographics, chief complaints, associated complaints, and previous care sought.</p> <p>Results</p> <p>The sample comprised 306 (61.2%) female. Most files (44.2%) were in the age range of 40–59 years (mean of 43.4 years). The most frequent complaints were lumbar pain (29.2%) and extremity pain (28.0%), most commonly the knee. Most (62.0%) described their complaints as greater than one year. Trauma (46.6%) was indicated as the initial cause. Mean VAS score was 6.26/10 with 20% rated at 8/10.</p> <p>Conclusion</p> <p>Demographic results compared closer to studies conducted with private clinicians (females within the ages of 40–59). The primary complaint and duration was similar to previous studies (low back pain and chronic), except in this population the cause was usually initiated by trauma. The most striking features were the higher number of extremity complaints and the marked increased level of VAS score (20% rated as 8/10).</p

In-situ investigation of EMC relaxation behavior using piezoresistive stress sensor

The relaxation behavior of an epoxy molding compound (EMC) subjected to a constant strain can cause new reliability challenges in automotive electronics. This problem will be exacerbated due to the ever-increasing demand in modern electronics systems for miniaturization with more functionality, yet it has not been studied extensively to mitigate its effect on reliability. In this study, a piezoresistive silicon-based stress sensor is used to understand the stress state in an electronic control unit (ECU), more specifically the relaxation behavior of EMC caused by the storage time of an ECU (i.e., duration between production and actual usage). Mechanical stresses are measured by the piezoresistive stress sensor that is encapsulated in a standard microelectronic 3 × 3 mm land grid array (LGA) package. The relaxation behavior is observed at three different temperatures for 1 week: 75 °C, 100 °C and 125 °C. The relaxation behavior is measured continuously for one more week after cooling the package to room temperature (at 25 °C). An additional test is conducted at 85 °C with 85% relative humidity to investigate the effect of moisture diffusion on the package. The experimental results clearly indicate that the proposed approach can be used for better understanding of the evolution of stresses in molded packages during their lifetime, especially during storage, which in turn can lead to more optimal designs in the future

Towards prognostics and health monitoring: The potential of fault detection by piezoresistive silicon stress sensor

A piezoresistive silicon based stress sensor has been demonstrated successfully as an effective tool to monitor the stresses inside electronic packages during various production processes. More recently, the sensor has been evaluated as a sensor for Prognostics and Health Monitoring (PHM) systems. This paper presents a systematic approach that evaluates its performance from the perspective of failure mode detection. A detailed Finite Element method (FEM) model of existing test vehicles is created. The test vehicle consists of six DPAK (Discrete Package) power packages and three stress sensors. The results of simulation are verified by the signals obtained from the stress sensor as well as the supplementary warpage measurements. After inserting various failure modes into the model, statistical pattern recognition algorithms are implemented for fault detection and classification. The proposed technique can identify detectable failures during reliability testing by utilizing the database of stress sensor responses for healthy and unhealthy state. Thus, the results establish a baseline for the applicability of the piezoresistive stress sensor for an on-line monitoring PHM methodology

Application of the IForce piezoresistive silicon based stress sensor for prognostic and health monitoring methods

Miniaturization and simultaneous increase of complexity and functionality of modern electronic control units (ECU) leads to the situation that the classical reliability methods become less and less sufficient. Reliability prediction in automotive industry is complex, as the load history on the system level (e.g. car) is multi-domain and depends on many different factors such as the climate, the type of the car, user, etc. Currently, the reliability of the ECU's is assessed on the subsystem level. In order to assess reliability on the system level, prognostic and health monitoring (PHM) is the most promising method. In this paper the IForce, piezoresistive, silicon based stress sensor is implemented to monitor the stress state during passive and active power cycling (APC) of the ECU. Two ECU's-original and overmolded are subjected to combined active power and passive thermal cycling. The active power is dissipated in the commercially available DPAK IC package

How Artists Can Develop Their Artwork, Its Market and Deliver Their Creative Content for Virtual Reality Environments?

This research investigates how artists, from traditional fine art and applied art backgrounds, can create innovative immersive and virtual art and build upon their tangible skills, through a digital pipeline and tools? Findings indicated opportunities to co-create partnerships, develop transferable design skills; and exhibitions which enable new markets and audiences