84 research outputs found
Synthesis of Ag-DLC coatings for biomedical implants
No full textThe diamond-like carbon (DLC) coating has the potential to increase the lifetime of metal on polymer (MoP) type hip joints due to its good tribological and mechanical properties as well as excellent biocompatibility. However, the high internal compressive stress of DLC films limits their adhesion with CoCrMo alloy. The high internal stress can be minimized by doping the DLC coating with metals like Ti, Cu, W, Nb and many more.
In the present thesis work, silver (Ag) doped diamond-like carbon (DLC) coatings were prepared on the CoCrMo alloy using direct current (DC) magnetron sputtering for biomedical implants. The silver concentration was varied in the DLC matrix by varying the DC power to the silver target from 12 W to 18 W. Raman spectroscopy was carried out to evaluate the structural changes in the carbon matrix. X-ray photoelectron spectroscopy (XPS) was used to measure the concentration of Ag and sp3 carbon hybridization in the coatings. The hardness, tribological behavior, and adhesion properties were characterized using nano-indentation, wear testing, and Rockwell C indentation, respectively. The hardness values show that initially, with a low percentage of silver, the residual stresses decrease drastically, whereas the hardness values decrease slightly. The lowest wear rate was observed for the coating doped with 7.4 at% of silver among all coatings, and improved adhesion was observed for all the Ag-DLC coating on CoCrMo alloy. The results showed that silver doped DLC coating is promising for a total hip joint replacement application
Understanding the efficiency of hydraulic actuation systems using the concept of cyclic performance index
No full textThis research develops and applies a new approach for evaluating the performance of hydraulic systems, with particular emphasis on those incorporating Energy Storage and Reutilization (ESR) circuits. Hydraulic systems are widely used in industry for their high-power density and versatility. Yet, current performance evaluation methods, such as energy-saving ratios, relative efficiency, and Sankey flow diagrams, are limited. These methods do not adequately account for stored and reutilized energy, making it difficult to fairly compare systems or accurately assess the benefits of energy recovery. To address this problem, the study applies the Cyclic Performance Index (CPI), a metric introduced by Costa and Sepehri [1], which evaluates all energy flows in the system. The CPI incorporates input energy from the prime mover, recoverable energy from the load, and energy losses during operation, thereby providing a more comprehensive framework for performance assessment.
The CPI methodology is validated through MATLAB simulations of Electro-Hydrostatic Actuators (EHA) configured with and without Energy Storage and Reutilization (ESR) circuits. This approach allows direct comparison between standard configurations and those equipped with energy recovery capability. The results show that, when ESR circuits are integrated, overall energy performance improved by approximately 40%, with CPI values increasing from 0.15 to 0.21. These results confirm the practical utility of CPI for capturing the impact of energy storage and reuse. The study also identifies limitations, especially where some stored energy is not fully reutilized due to system losses. This highlights the need for further optimization of ESR circuit design to enhance recovery efficiency.
In conclusion, the CPI offers a standardized and reliable tool for evaluating hydraulic systems with or without energy recovery. By measuring the balance of energy consumption, storage, and reuse, it allows for more precise comparisons between different system configurations. This research supports the development of energy-efficient and sustainable hydraulic technologies by illustrating both the advantages of ESR integration and the value of CPI as a performance evaluation metric.February 202
Implementation of patient health questionnaire in a primary care setting
No full textPurpose of Project:
Chronic medical illness (CMI) is the leading driver of increasing health care cost. Undiagnosed and untreated depression can add fuel, leading to serious repercussions in patients with CMI. Patients with depression are 2-3 times more likely to develop the chronic medical illness (CMI). Depression is one of the most common mental health disorders with lifetime prevalence of 10.8-16.2%. Depression can be easily detected in a primary care office where only 50% of patients are currently being diagnosed. Patients with CMI visit their primary care doctors on a regular basis which makes the primary care office the best place to detect depression. Depression screening can be easily done using the Patient Health Questionnaire (PHQ) -9, a self-administered tool. The goal of this hybrid project was to increase detection rate of depression in patients with CMI at a primary care office in a suburban area of southern New Jersey. This was achieved by screening participants with PHQ-9 during the initial or follow-up visit. A targeted qualitative question was also asked to better understand the patient’s perception of frequent depression screening. The goal was to screen approximately 40 participants within an 8-weeks period. Screening for depression in a primary care office helps us to increase access and delivery of quality health service. Increasing the number of patients diagnosed for depression will lower the incidence of suicide and help patients to receive treatment at the same place. Patient satisfaction will increase as well.
Methodology:
Project Type – Hybrid (Quantitative and Qualitative)
Setting – Solo primary care practice in a suburban area
Population – 18-89 years with at least one diagnosis of CMI
Recruitment strategy – Voluntary, convenience sample recruitment via flyers, and 1:1 approach
Consent procedure – Face to face interaction only in a private consultation room
Risks/Harm – Minimal risk and confidential (during the intervention, if participants get upset then he/she will be counseled/evaluated by the provider)
Cost/Compensation – Free, no compensation
Measurable Outcomes – PHQ-9 score and demographics
Results:
Total number of participants = 30 (n) of the 40 (target)
18 males (60%) and 12 females (40%)
Out of 30 total participants, only 1 was already diagnosed with depression and was not on any treatment for personal reason
10 patients refused to participant for unknown reasons
Most of the participants were
Married (n=20, 66.7%)
Asian (n=24, 80%)
Middle-aged (age 45-64, 50%)
Bachelor’s degree holder (n=19, 63.3%)
Implications for Practice:
Currently there is no existing mandatory policy related to depression screening other than routine wellness visit screening. Creating change at a national level will be an upstream intervention to address undiagnosed undertreated depression affecting large population throughout the United States. Policy should be made to cover the related cost by all insurance provider to decrease burden over the patient. Ultimately, it will lower the cost of maintenance of CMI and depression with improvement in quality of life. Additional training/education should be provided to the project site staff. Safety of the patient can be served if we can detect depression in-time and help the patient to obtain proper resources. Timely identification can help to increase life expectancy, treatment adherence and may lower suicide risk. Continuing education to both the provider and the patients is necessaryDNPIncludes bibliographical reference
Various methods to assess knee proprioception: A review
No full textIntroduction: Proprioception is a vital aspect of motor control and when degraded or lost can have a profound impact on function in diverse clinical populations. This systematic review aimed to identify clinically related tools to measure proprioceptive acuity. The major purpose of this systematic review was to identify and categorise the methods that have been developed and utilised to test proprioceptive accuracy in a comprehensive manner. Methods: The pub med, Scopus, Web of Science and the other search engine/databases used: Cochrane database / SCIRE / PEDro / CINAHL/ EMBASE, ERIC were systematically searched. Conclusions: The TTDPM method has less relative ecological validity, but has high conceptual purity, Although JPR tests may have less relative test validity, but more clinically feasible, The AMEDA method appears to have better ecological validity and relatively better test validity and data validity
Plant aquaporins alleviate drought tolerance in plants by modulating cellular biochemistry, root‐architecture, and photosynthesis
No full textAdvancing MRI-Guided Cardiac Interventions Using 3D Cones Imaging
No full textVentricular tachycardia (VT), a life-threatening arrhythmia often associated with myocardial infarction, poses significant challenges in clinical management due to the difficulty in identifying reentry circuits and accurately targeting arrhythmogenic substrates during treatment. Radiofrequency (RF) ablation is an effective therapy for VT, but its success is limited by high recurrence rates, largely due to inadequate imaging and guidance techniques. Magnetic resonance imaging (MRI) offers transformative potential in addressing these limitations by providing high-resolution scar mapping, real-time device guidance, and precise post-ablation lesion assessment. However, the prolonged acquisition times of conventional MRI techniques hinder their widespread application in intraprocedural settings.
This thesis focuses on advancing fast 3-dimensional (3D) imaging techniques using the 3D cones trajectory to enable real-time MRI-guided interventions for VT treatment. The work is structured into three primary contributions. Chapter 2 develops an imaging framework for simultaneous 3D tracking of interventional devices, and anatomical and catheter shaft visualization, validated through static and dynamic phantoms, and in vivo experiments. Chapter 3 evaluates the use of 3D cones imaging for fast visualization of RF ablation lesions, demonstrating significantly reduced acquisition times for native T1-weighted and late gadolinium enhancement imaging compared to the standard Cartesian image sequence. Lesion sizes and characteristics were validated against gross pathology, ensuring clinical relevance. Chapter 4 improves 3D cones reconstruction with contrast-enhanced techniques, allowing detailed scar imaging and VT corridor (substrate) identification for adaptive treatment planning. These advances facilitate the integration of scar and lesion characterization into intraprocedural workflows, improving VT substrate targeting and procedural outcomes.
The findings underscore the potential of 3D cones imaging to revolutionize VT treatment by combining fast acquisition, high spatiotemporal resolution, volumetric spatial coverage, and robust scar and lesion visualization. This work represents a significant step toward comprehensive 3D MRI-guided VT interventions, potentially paving the way for improved procedural precision and long-term patient outcomes.Ph.D
Role of sodium proton antiporters in cellular homeostasis of plants under abiotic stress conditions
No full textStabilization of an inverted pendulum using fuzzy logic controller
No full textThe main goal of this project is to study two different techniques of stabilizing the Inverted Pendulum System. Firstly, a mathematical model of an inverted pendulum is derived in differential equations. In second part a PID controller is designed to stabilize the system, which is implemented using MATLAB Simulink. In the third part, a fuzzy logic controller is built using Fuzzy Logic tool box in MATLAB. In the end simulation results based on the PID Controller and Fuzzy Logic Controller, have been observed and compared. Both the controllers show the satisfactory results in stabilization of an Inverted Pendulum System. PID Controllers are much easier to implement and design, and used in comparatively less complicated and mostly linear systems, while fuzzy Logic controllers, mostly are used in highly non-linear and complicated systems
Design and validation of NTRU public-key cryptosystem
No full textProject (M.S., Electrical and Electronic Engineering) -- California State University, Sacramento, 2010.Design and validation of NTRU public-key cryptosystem is a relatively new Public Key Cryptosystem. Public Key Cryptography or Asymmetric Cryptography is used in areas of digital signatures and key exchange. RSA is an acclaimed Public Key cryptosystem that is in use since 1977. However, it is very slow in comparison with Symmetric Cryptography systems in processing bulk data encryption and decryption. In contrast, NTRU runs much faster on large data systems than RSA and has become a very popular algorithm today in terms of data encryption and decryption. The key generation process in NTRU is much faster than that in RSA, and this process is one of the most important processes in Public Key Cryptography.\ud
FPGAs are one of best hardware used for implementing reconfigurable computing. Reconfigurable computing is very popular because it is capable of computing many different applications with a great speed. An important feature of reconfigurable computing is that computations are performed in hardware, but the flexibility of a solution in software is maintained at the same time.\ud
The purpose of this project is to initially explain the NTRU algorithm which is a proprietary algorithm patented by NTRU Cryptosystems. NTRU Crptosystems has recently become a part of Security Innovations, a leading provider of security solutions. This project advocates a hardware implementation of the NTRU public-key cryptosystem which is made of three important phases- Key Creation, Encryption and Decryption. The system has been implemented in Verilog HDL, simulated using Synopsys from VCS and synthesized using Xilinx ISE Design Suite.Electrical and Electronic Engineerin
Association of Age, Gender and Body Mass Index with Proprioception in Knee Joint in Healthy Individuals
No full textBackground: The word proprioception is derived from Latin word “proprius” means it is one’s own and “reception” means it receives. In Musculoskeletal rehabilitation, proprioception plays significant role in maintaining normal motor control. The proprioception is an important non-invasive clinical procedure which helps in diagnosing pre-existing and treating knee conditions. Proprioception assessment is foremost because loss in proprioception will lead to altered weight bearing at joints and alteration of normal body movement causing fall or injury. Purpose of this study is to find out the association of knee joint proprioception with age, gender and BMI in healthy individuals. Methods: Total 132 participants are included in the study. Their height and weight was measured to calculate their BMI. After that, proprioception was assessed with the help of goniometer mounted on the stand. Knee joint proprioception was measured for Test angles 30°, 45° and 60° toward extension. At all angles test was performed three times in sequence. Result: The collected data were analyzed in SPSS software version 21.0. At 30° correlations between both side of knee joint proprioception with Age, Gender and BMI was non-significant except left side of proprioception with gender. However, at 45° correlations between both side of knee joint proprioception with Age, Gender and BMI was found significant. Additionally, similar of most result was found at 60° except left side of knee joint proprioception was found not significant with BMI. Conclusion: Knee joint proprioception decreases with ageing and are more in females than males. This study finds weak to moderate correlation with BMI
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