Mobilise-D insights to estimate real-world walking speed in multiple conditions with a wearable device

This study aimed to validate a wearable device’s walking speed estimation pipeline, considering complexity, speed, and walking bout duration. The goal was to provide recommendations on the use of wearable devices for real-world mobility analysis. Participants with Parkinson’s Disease, Multiple Sclerosis, Proximal Femoral Fracture, Chronic Obstructive Pulmonary Disease, Congestive Heart Failure, and healthy older adults (n = 97) were monitored in the laboratory and the real-world (2.5 h), using a lower back wearable device. Two walking speed estimation pipelines were validated across 4408/1298 (2.5 h/laboratory) detected walking bouts, compared to 4620/1365 bouts detected by a multi-sensor reference system. In the laboratory, the mean absolute error (MAE) and mean relative error (MRE) for walking speed estimation ranged from 0.06 to 0.12 m/s and − 2.1 to 14.4%, with ICCs (Intraclass correlation coefficients) between good (0.79) and excellent (0.91). Real-world MAE ranged from 0.09 to 0.13, MARE from 1.3 to 22.7%, with ICCs indicating moderate (0.57) to good (0.88) agreement. Lower errors were observed for cohorts without major gait impairments, less complex tasks, and longer walking bouts. The analytical pipelines demonstrated moderate to good accuracy in estimating walking speed. Accuracy depended on confounding factors, emphasizing the need for robust technical validation before clinical application. Trial registration: ISRCTN – 12246987

Switchable split-ring frequency selective surfaces

Abstract—Tunable frequency selective surfaces (FSSs) based on split ring resonators (SRRs) are presented. Tuning performance is achieved by means of several on/off switches placed between the rings of each SRR element. The band-stop FSS response is dynamically tuned to different frequency bands at different switching states. In addition, loadings placed at the corners of outer ring elements, forming a fan-like shape, with additional switches are shown to offer rather fine-tuning capability. A dual-layer FSS is also introduced to demonstrate a filter response over a larger frequency band, and also offers tunable dualband operation via switching. By using complementary SRR elements, a tunable band-pass response instead can be obtained using a similar switching configuration. Practical switch modeling is also examined in the paper along with the scanning performance of the SRR-FSS. The numerical analysis of the FSS designs is accomplished using a fast periodic array simulator, and the measurements demonstrate preliminary validation of the proposed switching configuration. 1

Tunable looploaded printed dipole antenna design

Introduction Compact multi-function antennas play a major role in today's communication systems where size, weight, power consumption and cost are the main limiting factors in designing integrated transmitter/receiver circuitry. In this view, electronically reconfigurable printed antennas were previously considered to achieve multi-band applications [1−4]. In particular, printed dipole elements have been preferred in conformal arrays due to their low-profile and easy fabrication. Specifically, loaded dipole elements have recently been introduced for dualfrequency applications [4−6]. In this paper, a new loop-loaded printed dipole (LLPD) antenna design is proposed for a tunable (3 GHz or 5.2 GHz) array application. The tunable-LLPD (TLLPD) design consists of a printed dipole element and a pair of loop elements with extensions employed for tuning purposes via on/off switches in a practical realization. We note that the full-wave analysis of the proposed designs have been carried out using CST Microwave Studio, which utilizes the time-domain finite-integration method. In the paper, we present the corresponding simulation and preliminary measurement results to demonstrate the performance of the proposed LLPD designs. Antenna Design The LLPD design has recently been introduced in [4] aiming for a dual-band array operation. Here we present a new LLPD element with stub extensions attached to the loops to achieve a tunable antenna operation. The proposed TLLPD configuration is depicted in The return loss characteristics of the TLLPD design along with that of the LLPD are displayed in In addition, the computed radiation patterns of the TLLPD design are shown in We also fabricated the prototypes of the LLPD antennas considered above, and the photograph of one of them is shown in As can be observed from Conclusion In the paper, we have introduced dual-band (3/5.5 GHz) as well as tunable single-band (3 GHz or 5.2 GHz) LLPD designs. The CST simulations have been compared with the measurements, revealing a need for a broadband balun/feed structure so as to improve the antenna performance. The proposed LLPD designs are projected to be utilized for a particular array application, which will be discussed at the conference as well as practical switch usage in the TLLPD design. Acknowledgmen

Risk of superior gluteal nerve and gluteus medius muscle injury during femoral nail insertion

PubMed: 17403807Background: Abduction weakness and limping is a well-recognized complication of closed antegrade insertion of femoral nails, latrogenic injuries to the superior gluteal nerve and the gluteus medius muscle are the most likely contributing factors. The purpose of this study of cadavers was to assess the risk of nerve and muscle injury with various lower-limb positions used during nail insertion. Methods: We studied thirteen hips of ten formalin-fixed adult cadavers. With the cadaver in the full lateral position, a 9-mm reamer was introduced in a retrograde fashion from the intercondylar notch and passed through the gluteus medius muscle. The distance between the point of entry of the reamer into the undersurface of this muscle and the inferior main branch of the superior gluteal nerve (the nerve-reamer distance) and the distance between the entry and exit points of the reamer in the gluteus medius muscle (the intramuscle distance) were measured in three different hip positions: 15° of flexion and 15° of adduction (Position 1), 30° of flexion and 30° of adduction (Position 2), and 60° of flexion and 30° of adduction (Position 3). Results: In Position 1, the average nerve-reamer distance was 7 mm and the average intramuscle distance was 24 mm. In three hips the reamer injured the nerve directly, and in two other hips the distance was ?5 mm. In Position 2, the average nerve-reamer distance was 21 mm and the average intramuscle distance was 18 mm. In Position 3, the average nerve-reamer distance was 33 mm and the average intramuscle distance was 11 mm. None of the reamers in this position came closer than 20 mm to the nerve. Conclusions: The risk of injury to the superior gluteal nerve and the gluteus medius muscle during closed antegrade insertion of a femoral nail is lessened by increasing the amount of hip flexion and adduction. Clinical Relevance: The risk of injury to both the superior gluteal nerve and the gluteus medius muscle is higher with limited degrees of hip flexion and adduction, such as are possible in the supine position on a fracture table, than it is with greater degrees of hip flexion and adduction, which are possible in the lateral position on a fracture table or in the so-called sloppy lateral position on an ordinary table. Therefore, insertion of a femoral nail with the hip in increased flexion and adduction might help to lower the risk of injuries to the superior gluteal nerve and the gluteus medius muscle. Copyright © 2007 by The Journal of Bone and Joint Surgery, Incorporated

Thymoquinone is protective against 2,3,7,8-tetrachlorodibenzo-p-dioxin induced hepatotoxicity

PubMed ID: 29701106We investigated changes in rat liver tissues following administration of thymoquinone (TQ) against 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) induced hepatotoxicity. Fifty rats were assigned randomly to five groups of 10 as follows: control, corn oil, TCDD, TQ and TCDD + TQ. Biochemical and histopathological analyses were conducted on liver tissue. We found that 30 day TCDD administration caused histopathological changes in liver including thickening of Glisson’s capsule, intracytoplasmic vacuolization in hepatocytes, sinusoidal dilation, vascular and sinusoidal congestion and inflammatory cell infiltration. TCDD administration increased malondialdehyde (MDA), total oxidant status (TOS), alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) levels in rat liver tissue and reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT) and total antioxidant status (TAS) levels compared to all other groups. In the TQ treated group, GSH, SOD, CAT and TAS levels increased compared to all other groups. MDA, TOS, ALT, AST, ALP levels decreased compared to all other groups. Our histological findings were consistent with the biochemical findings. The oxidative and histologic effects of TCDD were eliminated by TQ treatment. TCDD administration caused oxidative stress in rat liver and TQ administered with TCDD prevented TCDD induced hepatotoxicity. TQ could be considered an alternative anti-TCDD toxicity agent. © 2018, © 2018 The Biological Stain Commission

Hepatoprotective effects of crocin on biochemical and histopathological alterations following acrylamide-induced liver injury in Wistar rats

PubMed ID: 28892787The objective of the present study is the treatment of oxidative damage caused by acrylamide induced oxidative stress in rats with the administration of a strong antioxidant, namely crocin. High acrylamide (AA) levels have genotoxic, carcinogenic and neurotoxic effects on living organisms. In the present study, 40 Wistar rats were randomly divided into four equal groups. These groups were control, acrylamide (25 mg/kg), crocin (50 mg/kg), acrylamide + crocin (25 mg/kg acrylamide and 50 mg/kg crocin) groups. At the end of the application, biochemical and histological variations were examined in liver and blood samples. It was observed that acrylamide administration significantly decreased liver GSH and TAS levels when compared to the control group. On the contrary, it was also observed that AST, ALT, ALP, SOD and CAT activities and TOS and MDA levels increased as a result of acrylamide administration. Histopathological examinations demonstrated inflammatory cell infiltration, hepatocellular necrosis and hemorrhage areas in AA group liver sections. Furthermore, intracytoplasmic vacuolization was detected in hepatocytes. After crocin treatment, it was observed that GSH and TAS levels increased while AST, ALT, ALP, SOD and CAT activities and TOS and MDA levels decreased. Significant decreases were observed in inflammatory cell infiltration and vascular congestion in liver sections and intracytoplasmic vacuolization in hepatocytes after the crocin treatment, while no hepatocellular necrosis and hemorrhages were observed. In the present study, it was demonstrated that crocin treatment removed acrylamide induced liver damage due to the strong antioxidant properties of crocin. © 2017 Elsevier Masson SASThe present study was sponsored by Karabuk University Scientific Research Fund ( KBU-BAP-15/2-YL-010