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With an interest in monitoring the patency of stents that are used to treat strictures in the bile duct, this paper reports the investigation of a wireless sensing system to interrogate a microsensor integrated into the stent. The microsensor is comprised of a 28-μm-thick magnetoelastic foil with 8.25-mm length and 1-mm width. Magnetic biasing is provided by permanent magnets attached to the foil. These elements are incorporated into a customized 3D polymeric package. The system electromagnetically excites the magnetoelastic resonant sensor and measures the resulting signal. Through shifts in resonant frequency and quality factor, the sensor is intended to provide an early indication of sludge accumulation in the stent. This work focuses on challenges associated with sensor miniaturization and placement, wireless range, drive signal feedthrough, and clinical use. A swine specimen in vivo experiment is described. Following endoscopic implantation of the sensor enabled plastic stent into the bile duct, at a range of approximately 17 cm, the signal-to-noise ratio of ~106 was observed with an interrogation time of 336 s. These are the first reported signals from a passive wireless magnetoelastic sensor implanted in a live animal. [ABSTRACT FROM AUTHOR]

In electronic systems, flip-flops (FFs) are one of the fundamental elements that are used in high-performance processors. With the scaling of CMOS, occurs serious challenges such as higher leakage currents and higher static power consumption have been raised in high-performance circuits. Therefore, to address these issues, we explored carbon nanotube field effect transistors (CNTFETs) with multi-valued logic (MVL). In this paper, we designed an energy-efficient Pulse triggered Ternary Flip Flops (P-TFF) such as Data Close to Output (P-DCO-TFF), Signal Feed Through (P-SFT-TFF), and Delay (P-D-TFF) with pseudo NCFET (N-channel CNTFET) logic. These flip-flops use ternary logic, which is 0, Vdd/2, and Vdd as logic 0, 1, and 2, respectively. The complete design is done by the stanford 32 nm CNTFETs. The simulations are performed and waveforms are obtained in Cadence Virtuoso Software. We found that the suggested pulse-triggered TFFs performed better than the conventional ternary FF (C-TFF) structure in terms of energy, delay, and power. This simulation result shows 17.8%, 14%, and 47.7% energy reduction in P-SFT-TFF, P-DCO-TFF, and P-D-TFF, respectively, compared with C-TFF structure. Also performed the Monte Carlo Simulations to these proposed TFF designs. The P-D-TFF exhibits very efficient results in terms of delay, energy, and power consumption. This article also simulated the Ternary Universal Shift Register (TUSR) with Proposed P-D-TFF. [ABSTRACT FROM AUTHOR]

Advanced technology used for arithmetic computing application, comprises greater number of approximatemultipliers and approximate adders. Truncation and Rounding-based Scalable ApproximateMultiplier (TRSAM) distinguish a variety of modes based on height (h) and truncation (t) as TRSAM (h, t) in the architecture. This TRSAM operation produces higher absolute error in Least Significant Bit (LSB) data shift unit. A new scalable approximate multiplier approach that uses truncation and rounding TRSAM (3, 7) is proposed to increase themultiplier accuracy. With the help of foremost one bit architecture, the proposed scalable approximate multiplier approach reduces the partial products. The proposed approximate TRSAM multiplier architecture gives better results in terms of area, delay, and power. The accuracy of 95.2% and the energy utilization of 24.6 nJ is observed in the proposed multiplier design. The proposed approach shows 0.11%, 0.23%, and 0.24% less Mean Absolute Relative Error (MARE) when compared with the existing approach for the input of 8-bit, 16-bit, and 32-bit respectively. It also shows 0.13%, 0.19%, and 0.2% less Variance of Absolute Relative Error (VARE) when compared with the existing approach for the input of 8-bit, 16-bit, and 32-bit respectively. The proposed approach is implemented with Field-Programmable Gate Array (FPGA) and shows the delay of 3.640, 6.481, 12.505, 22.572, and 36.893 ns for the input of 8-bit, 16-bit, 32-bit, 64-bit, and 128-bit respectively. The proposed approach is applied in digital filters designwhich shows the Peak-Signal-to-NoiseRatio (PSNR) of 25.05 dB and Structural Similarity Index Measure (SSIM) of 0.98 with 393 pJ energy consumptions when used in image application. The proposed approach is simulated with Xilinx and MATLAB and implemented with FPGA. [ABSTRACT FROM AUTHOR]

Wireless magnetoelastic sensors offer significant potential for measuring the accumulation of biomass within stents—enabling early detection prior to stent occlusion—but the encapsulation of these sensors remains a critical challenge. The encapsulation must allow the sensors to navigate the curvature and accommodate the contact forces imparted during and after the implantation procedure, while also leaving the sensor open to mechanical interaction with the biomass during the extended period of deployment. This paper is focused on the encapsulation of ribbon-like magnetoelastic sensors (12.5 mm × 1 mm × 60 μm) within plastic biliary stents (inner diameter of 2.54 mm). The compromise between two polymer-based package designs—one mechanically flexible (Type F) and one mechanically stiff (Type S)—is evaluated. The primary advantage of the Type F package is the flexibility during the delivery process while that of the Type S package is in maintaining a strong signal even when the stent is in a curved bile duct. The maximum thicknesses of the Type F and S packages are 0.53 and 0.74 mm, respectively. Mechanical tests show that both types protect the sensors from forces imparted by a standard introducer, and allow the encapsulated sensors to accommodate bending with a radius of curvature as small as 3 cm. The Type F package has also been tested in situ, in the bile duct of a porcine carcass. The signal is measurable with a wireless range of ≍10 cm, at a resonant frequency of 159 kHz and a quality factor of 397. [ABSTRACT FROM AUTHOR]

Aims and Objectives: This study was conducted to compare the clinical assessment of impacted third molars of mandible with panaromic radiograph (OPG) and intraoral periapical radiograph (IOPA) and to assess the efficacy of IOPA and. Moreover, we corroborated the OPG and IOPA findings of impacted mandiblar third molar root apex to inferior alveolar canal. Materials and Methods: A total of 200 patients with pericoronitis were examined who were indicated for surgical extraction, among which 50 patients were selected for the study. All the patients underwent a radiographic survey with a digital OPG and IOPA of impacted mandibular third molars, along with clinical survey for anatomic relationship, type of impaction, space available, position in relation to second molar, number of roots, root curvature, and proximity of nerve canal. The data was subjected to statistical analysis. The Statistical Package for Social Sciences version 4.0.1 software was used for analyzing the collected data. Results: The study revealed that IOPA was more accurate in determining a majority of the factors affecting the third molar surgery, including relationship of the external oblique ridge (IOPA vs OPG = 96%:90%), anteroposterior relation with ramus (IOPA vs OPG = 70%:66%), vertical depth of impaction (IOPA vs OPG = 72%:68%), number of roots (P = 0.013), morphology of roots (IOPA vs OPG = 96%:90%); however, OPG was found to be accurate in evaluating the type of impaction (IOPA vs OPG = 88%:94%), canal relation, along with root of impacted molar (IOPA vs OPG = 74%:86%). Conclusion: To conclude, although IOPA has a marginal angle over OPG in assessing various parameters, only the number of roots have a greater accuracy (P < 0.0013) in IOPA than with OPG. However, the OPG is the better choice to be considered when the patient is associated with trismus. [ABSTRACT FROM AUTHOR]

Background: Carrying heavy backpacks could cause a wide spectrum of pain related musculoskeletal disorders and postural dysfunctions. Objective: To determine the changes in various postural angles with different backpack weights in preadolescent children. Design: Cross-sectional. Participants: Healthy male school-children (n=200), mean (SD) age: 12.5 (0.5) years, from high schools in Mangalore, India. Measurements: Bodyweight and height were measured using a forceplate and stadiometer, respectively. From the weight recorded, 5%, 10%, 15%, 20%, and 25% of the bodyweight were calculated and implemented as their respective backpack loads. The Image Tool version 3.0, digitizing software was used for analyzing photographs to determine craniovertebral (CV), head on neck (HON), head and neck on trunk (HNOT), trunk and lower limb angles. Postural angles were compared with no backpack and with backpacks weighing 5% to 25% of the subject's bodyweight. Results: The CV angle changed significantly after 15% of backpack load (P <0.05). The HON and HNOT angles changed significantly after 10% of backpack load (P <0.05). The trunk and lower limb angle also changed significantly after 5% of backpack load (P <0.05). Conclusions: Carrying a backpack weighing 15% of body weight change all the postural angles in preadolescent children. [ABSTRACT FROM AUTHOR]

Background: Preprogrammed reactions (PPR) appear at a latency of higher than 40 ms, but before the voluntary muscle responds (~ 120 ms) to postural perturbations. Objective: To examine the difference in magnitude of preprogrammed reactions in patients with chronic low back pain (CLBP) and without low back pain. Methods: we analyzed electromyographic Root Mean Square (RMS) amplitudes of asymptomatic (n=25) and CLBP patients (n=25) on stable and unstable surfaces during expected and unexpected perturbations for rectus abdominus and erector spinae muscles. The mean PPR and PPR-combined voluntary response RMS amplitudes (VRPPR) were compared between the two groups. To find the presence of PPR in LBP patients, a criteria was set that the obtained PPR RMS amplitude value should exceed 60% mean reflex RMS amplitude that occur within 50 ms after perturbation. Results: Fleiss' kappa revealed a good agreement ([kappa] = 0.7 to 0.9) among raters for absence of PPR in patients with CLBP and presence of PPR in asymptomatic population. The two way ANOVA revealed significantly different mean PPR and VRPPR RMS amplitudes between asymptomatic and LBP population for rectus abdominus and erector spinae muscles (p< 0.05). Conclusion: PPR responses were found absent (< 60% of Mean Reflex RMS) in patients with CLBP. Further, patients with CLBP demonstrated lower PPR amplitudes with higher peak voluntary responses compared to asymptomatic population, indicating difficulties in presetting of voluntary responses for regaining postural stability after perturbation. [ABSTRACT FROM AUTHOR]

Background: Preprogrammed reactions (PPR) appear at a latency of higher than 40 ms, but before the voluntary muscle responds (∼ 120 ms) to postural perturbations. Objective: To examine the difference in magnitude of preprogrammed reactions in patients with chronic low back pain (CLBP) and without low back pain. Methods: we analyzed electromyographic Root Mean Square (RMS) amplitudes of asymptomatic (n=25) and CLBP patients (n=25) on stable and unstable surfaces during expected and unexpected perturbations for rectus abdominus and erector spinae muscles. The mean PPR and PPR-combined voluntary response RMS amplitudes (VRPPR) were compared between the two groups. To find the presence of PPR in LBP patients, a criteria was set that the obtained PPR RMS amplitude value should exceed 60% mean reflex RMS amplitude that occur within 50 ms after perturbation. Results: Fleiss' kappa revealed a good agreement (κ = 0.7 to 0.9) among raters for absence of PPR in patients with CLBP and presence of PPR in asymptomatic population. The two way ANOVA revealed significantly different mean PPR and VRPPR RMS amplitudes between asymptomatic and LBP population for rectus abdominus and erector spinae muscles (p< 0.05). Conclusion: PPR responses were found absent (< 60% of Mean Reflex RMS) in patients with CLBP. Further, patients with CLBP demonstrated lower PPR amplitudes with higher peak voluntary responses compared to asymptomatic population, indicating difficulties in presetting of voluntary responses for regaining postural stability after perturbation. [ABSTRACT FROM AUTHOR]

Presents information on a study which described the cloning and expression of a human macrophage receptor that binds to apolipoprotein B48. Characteristics and cloning of apolipoproptein B48; Methodology; Results and discussion.

A reply by M. Ramprasad to a letter to a editor about his article "Effect of Backpack Weight on Postural Angles in Preadolescent Children" in a 2010 issue is presented.