58 research outputs found

    Automated Analysis of Intracranial Aneurysm Morphology and Dynamics from CTA Data

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    The worst headache of his life, a sudden onset of severe headache accompanied by nausea, blurred vision, stiff neck and loss of consciousness, happened when he was simply at home doing daily activities. He had no symptoms before it happened and after he was taken to the hospital, he was diagnosed with aneurysmal subarachnoid hemorrhage. Cerebrovascular diseases, mainly stroke, are the second leading causes of death worldwide according to the WHO. Approximately 5% to 15% of stroke cases have aneurismal origin with a 30-day mortality rate of 45%. Among the survivors 30% has moderate-to-severe disabilities . No less than an estimated 2% of the population has an intracranial aneurysm but fortunately only a few of them rupture, with an annual estimated risk of 0.7% . Research shows that most aneurysms are small and 50% to 80% of them do not rupture during the course of a person’s life. Between 10% to 30% of the patients have multiple aneurysms

    Study of temperature-curvature relationships in Bi-stable composite laminates

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    The interest in bi-stable structures comes from their ability that these structures can have two different stable equilibrium configurations to define a discrete set of stable shapes. The geometrical changes occur with no need to continuously consume power, and mechanical hinges to preserve the structure in each stable shape. It is known that asymmetric composite laminates can have bi-stable response to different kind of loadings. In this research, the non-linear temperature-curvature relationship for the asymmetric composite laminates is studied using Rayleigh–Ritz technique. Attention is focused on studying the effect of material temperature dependency and resin layers; especially in the bifurcation point by use of analytical method. To this end, the well-known analytical theories are extended and used to consider the temperature dependency of material. The results obtained from the theory are then compared with the finite element simulations results and a good correlation is obtained. Finally, an experimental investigation is carried out and several specimens with [90/0] T, [70/–20]T and [70/20]T compositions were manufactured. In order to study the effect of resin layers, optical microscopy is utilized and the exact thickness of different layers in the manufactured specimens is determined. The thermal responses of the manufactured plates were measured and used to validate the results obtained from the analytical theory and finite element simulations

    Test infrastructure for indicator-based smart glasses

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    Approximately 5% of the elderly people, over age 65, suffer from one kind of dementia such as Alzheimer’s disease, frontotemporal dementia and AIDS dementia. It is estimated population of senior citizens all over the world will almost double in the next 25 years. Accordingly, prevalence of dementia in aging generation increases essential need in resources dedicated to caretaking of senior citizens, such as facilities, financial and human resources. It opens doors to emergence of new semantic technologies, which aim to assist senior citizens in daily life tasks. The systems should be safe, effective and patient-centered, and they must provide timely, efficient and equitable care to patients. Focuses on health, physical condition monitoring and assistive navigation technologies are the main categories to improve life quality of senior citizens. This study is dedicated to introducing a Head Mounted Display system to assist senior citizens in daily navigational tasks. In addition, usability test infrastructure is explained to evaluate system usability and improve the system in iterative test plans. The main research question clarifies main objective of the study as an investigation on usability of HMD system through several sub-questions evaluating various factors in the system and customers’ preferences. HMD system consists of the Indicator-based Smart Glasses and Bluetooth headset. Set of LED indicators is implanted around the lenses in the frame of the Smart Glasses. LED cues are supposed to convey navigational commands to users. Design science method with applied qualitative and quantitative approaches defines research method while Goal Question Metrics forms the framework of the study to improve the usability of the system. Satisfaction level and various metrics in the system are evaluated via unstructured interviews, Bayesian analysis and measuring quantitative variables. Furthermore, severity of dementia is assessed through questionnaires in MMSE from. Evaluating different factors and metrics in the system through iterative usability tests lead to improvement in design and defining optimized blinking patterns in LED indicators configurations to convey navigational commands. Blinking patterns in the Smart Glasses include localizing indicators, blinking duration time, frequency and brightness. Usability tests with senior citizens as subject demonstrates that severity level of dementia could strongly affect users’ performance. Senior citizens who are suffering from severe and moderate dementia fail to accomplish the tasks in using the assistive tool. Accordingly, senior citizens, who are suffering from mild dementia and are in the initial stage of dementia, should be considered as the subject of future usability tests

    Comparison of the antibacterial effects of Persica, Matrica and chlorhexidine gluconate mouthwashes and normal saline in mechanically ventilated ICU patients: A clinical trial

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    Background: Bacterial colonization in the pharynx is one of the most important risk factors for ventilator-associated pneumonia. The aim of this study was to determine and compare the anti-bacterial effects of different mouthwashes in mechanically ventilated patients. Materials and Methods: In this double-blind randomized clinical trial, 80 patients were selected from the intensive care units (ICUs) of Imam Khomeini Hospital in Sari City, Iran, during 2010-2011, and were divided into four groups of 20 cases. The first intervention group was administered with chlorhexidine gluconate (CHX) 0.2 mouthwash, the second group Persica herbal 10 mouthwash, the third group was administered with Matrica 10 and finally in the fourth group, normal saline was used. In order to culture Staphylococcus aureus and Streptococcus pneumoniae, oropharynx samples were obtained without any stimulation prior and 6 min following oral rinsing. Results: Bacterial colonies were decreased significantly after the intervention in all four groups (P<0.001). Chlorhexidine gluconate, Persica and Matrica mouthwashes caused to decrease the Staphylococcus aureus (P<0.001, P<0.008 and P=0.01, respectively) and Streptococcus pneumoniae (P<0.001) positive cultures after the intervention. Conclusion: Herbal oral mouthwashes including Persica and Matrica are effective in decreasing Staphylococcus aureus and Streptococcus pneumoniae colonized in the oropharynx of mechanically ventilated patients. Therefore, after further investigations, they can serve as suitable alternatives for CHX in ICU settings

    Control of Nonlinear Vibration in Bi-Stable Composite Plates using Fuzzy Logic

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    Having two stable configurations and no need to any permanent energy sources for remaining in each of these stable states, bi-stable composite plates have gained many applications. This paper has concentrated on control and dynamic response of cross ply bi-stable composite plates (0.90). To do this, using Hamilton principle , Rayleigh-Ritz method, and a MATLAB programme specifically designed for this study, have been applied in order to extract  the governing equation of motions in plates. Then, in order to control the large vibration of the cross ply bi-stable plate, a fuzzy controller was proposed using a fuzzy logic and its prformance was simulated by Simulink in Matlab environment. In order to simulate the real conditions on the controller performance, the effect of disturbances and time delay on the responses of controller were also investigated

    The effect of intravenous aminophylline on stone free status after transureteral lithotripsy (TUL): a randomized double blind clinical trial study

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    Background: The third common urinary tract disease was renal stone, after the UTI and pathologic states of kidney. TUL is most useful and effective for removing the stones of inferior ureter. In other hand aminophylline can decrease urinary tract spasm. Then, combination of TUL and aminophylline help us to reduce the complication of TUL. Methods and materials: We have study on 87 case of renal colic who referred to Imam Khomeini hospital of sari and Tooba clinic. This study was a double blind systematic randomized clinical trial that patients were divided to two group as 1 and 2: group one includes patients who received aminophylline and group 2 were selected as our control samples. Our sample size was calculated by statistic analysis according to recent studies. Result: The average of TUL time was 5.12± 1.77 min in group 1 and 6.59± 3.47 min in group 2(p0.05). ESWL was used in one patient of group 1 because of remaining of stone, but 7 patients of group 2 did not response to Transureter lithotripsy, then they needed ESWL. Complication were not seen in patient who received Aminophylline and mean arterial pressure and heart rate was equal in two group. Conclusion: The difference of TUL Time between two groups was meaningful. As you know, aminophylline has an antispasmotic effect on urinary tract and tract with smooth muscle, and according to our finding, usage of aminophylline can reduce the complication of TUL and increase success rate of Lithotripsy in this patient. In other hand, it complications was few

    Comparison of totally tubeless percutaneous nephrolithotomy and standard percutaneous nephrolithotomy for kidney stones: a randomized, clinical trial

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    This study aimed to compare the totally tubeless percutaneous nephrolithotomy and standard percutaneous nephrolithotomy techniques regarding their rates of success and complications in patients with kidney stones. Patients were randomly assigned to two groups. Forty-four patients (24 men; mean age: 50.40±2.02 years) received totally tubeless percutaneous nephrolithotomy (PCNL; no nephrostomy catheter or ureteral catheter after PCNL) and 40 patients (18 men; mean age: 49.95±13.38 years) underwent standard PCNL (a nephrostomy catheter and ureteral catheter were used after PCNL). All surgeries were performed by one surgeon. Postoperative changes in hemoglobin, the blood transfusion rate, changes in creatinine levels, operation time, analgesic need, hospitalization time, and complication rate were compared between the groups. No significant differences were observed in age, gender, stone size, and surgery side between the groups (P<0.05). The operation time was significantly lower in the totally tubeless PCNL group than in the standard PCNL group (P=0.005). Pethidine requirements were significantly higher in the standard PCNL group than the totally tubeless PCNL group (P=0.007). Hospitalization time was significantly higher in the standard PCNL group than in the totally tubeless PCNL group (P<0.0001). The complication rate was 15% in the standard PCNL group and 9.1% in the totally tubeless PCNL group (P=0.73). The totally tubeless PCNL technique is safe and effective, even for patients with staghorn stones. This technique is associated with decreased pain, analgesic needs, and operative and hospitalization time. We believe that a normal peristaltic ureter is the best drainage tube

    Cognitive deficit in first-time coronary artery bypass graft patients: A randomized clinical trial of lidocaine versus procaine hydrochloride

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    Introduction: Cognitive dysfunction increasingly has been recognized as a complication after cardiac surgery. Different methods have been considered for the reduction of cognitive dysfunction after cardiac surgery. One of these methods is by using lidocaine during surgery. The aim of this study was to determine the effects of adding lidocaine to the cardioplegia solution on cognitive impairment after coronary artery surgery. Design and methods: In a prospective, randomized, double-blind trial, 110 patients aged between 20-70 years, scheduled for elective CABG surgery using cardiopulmonary bypass, were recruited into the study. They were randomized into two groups who received either cardioplegia solution containing lidocaine 2 mg/kg or procaine hydrochloride 5 mg/kg. The neurocognitive test used in this study was the Mini Mental State Examination (MMSE) or Folstein test. The test was done on the day before and 10 days and 2 months after the operation. Results: In the procaine group, the total score after 10 days decreased significantly compared to the preoperative score (mean difference 0.68; 95% CI: 0.20 to 1.17, p=0.006). Comparison between mean differences after 10 and 60 days of operation between the lidocaine and procaine groups were statistically significant, p-value 0.017 and 0.013, respectively. There was no cognitive impairment in the lidocaine group, but, in the procaine group, four patients (7.7%) after 10 days and one patient (1.9%) after both 10 and 60 days had cognitive impairment, p=0.051. Conclusions: Administration of lidocaine compared to that of procaine through the cardioplegia solution had a better effect on cognitive function after coronary artery bypass graft surgery. © The Author(s) 2012
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