1,101 research outputs found
Control of a gantry crane using input shaping schemes with distributed delay
This paper presents simulation and real-time implementation of input-shaping schemes with a distributed delay for control of a gantry crane. Both open-loop and closed-loop input-shaping schemes are considered. Zero vibration and zero vibration derivative input shapers are designed for performance comparison in terms of trolley position response and level of sway reduction. Simulation and experimental results have shown that all the shapers are able to reduce payload sway significantly while maintaining satisfactory position response. Investigations with different cable lengths that correspond to 620% changes in the sway frequency have shown the distributed delay-based shaper has asymmetric robustness behaviour. The shaper provides highest robustness for the case of 20% increase in the sway frequency but lower robustness for the case of 20% decrease. However, other schemes give symmetric robustness behaviour for both cases
Reducing Grip Uncertainty During Initial Prosthetic Hand Use Improves Eye-Hand Coordination and Lowers Mental Workload
The reliance on vision to control a myoelectric prosthesis is cognitively burdensome and contributes to device abandonment. The feeling of uncertainty when gripping an object is thought to be the cause of this overreliance on vision in hand-related actions. We explored if experimentally reducing grip uncertainty alters the visuomotor control and mental workload experienced during initial prosthesis use. In a repeated measures design, twenty-one able-bodied participants took part in a pouring task across three conditions: (a) using their anatomical hand, (b) using a myoelectric prosthetic hand simulator, and (c) using a myoelectric prosthetic hand simulator with Velcro attached to reduce grip uncertainty. Performance, gaze behaviour (using mobile eye-tracking) and self-reported mental workload, was measured. Results showed that using a prosthesis (with or without Velcro) slowed task performance, impaired typical eye-hand coordination and increased mental workload compared to anatomic hand control. However, when using the prosthesis with Velcro, participants displayed better prosthesis control, more effective eye-hand coordination and reduced mental workload compared to when using the prosthesis without Velcro. These positive results indicate that reducing grip uncertainty could be a useful tool for encouraging more effective prosthesis control strategies in the early stages of prosthetic hand learning
Use of Medicinal Plants and Natural Products for Treatment of Osteoporosis and Its Complications
Opportunistic salpingectomy during hysterectomy for benign indications in women at low and high risk for ovarian cancer: a cross-sectional study
Objective
Our study aims to evaluate the role of pathology evaluation of fallopian tubesduring hysterectomy for benign indications for the purpose ofearly detection of serous tubal intraepithelial carcinoma (STIC) in women at high and low risk for ovarian cancer.
Material and methods
This cross-sectional study was conducted at Minia Maternity University Hospital, Egypt, between June 2015 and December 2017. Our study included all women undergoing hysterectomy for benign conditions in the genital tract. Appropriate histories were taken, as well as physical exams, and laboratory and ultrasound evaluations were done prior to scheduling surgery. Abdominal hysterectomies including opportunistic salpingectomies were performed and the whole specimens including the tubal fimbria were sent to the pathology lab for histo-pathological examination.
Results
A total of 526 patients met inclusion criteria for this study. The mean age of the study participants was 49.75±8.95 years, the mean parity was 3.91±1.62 and the mean BMI was 24.21±2.38 Kg/m2. The most common surgical indications for hysterectomy were postmenopausal bleeding (34.6%), a clinically benign adnexal/pelvic mass (31.7%), and menorrhagia (24.7%). The fallopian tubes were found to have either no pathology or benign conditions in 500 out of the 526 patients. Among these patients, 56% had no pathologic abnormality. The most common benign conditions were paratubal cysts (25%), endometriosis (9%), torsion (2%) and hydrosalpinx (1%). STIC was identified in the fallopian tubes of 8 out of 526 patients.
Conclusions
Microscopic examination of the entire fimbriae from all patients regardless of the clinical context represents a novel method of early detection of sporadic tubal carcinoma, a putative precursor to advanced-stage pelvic cancer
Risk Factors in the Patients with Extracranial Carotid Atherosclerosis
There are vascular risk factors known to be associated with stroke. These risk factors have been shown to either directly or indirectly lead to stroke. The risk factors include hypertension (HT), diabetes mellitus (DM), smoking, hyperlipidaemia, ischemic heart disease (IHD) and atrial fibrillation (AF). Studies have shown that carotid atherosclerosis is a cause of stroke. Extracranial carotid atherosclerosis accounts for up to 40% of the ischemic strokes in the Western countries. The latest stroke guidelines recommend the routine use of Ultrasound Carotid Doppler to assess for extracranial carotid artery atherosclerotic diseases (carotid intima media thickness, plaques, carotid stenosis) in these patients. A previous study emphasized the value of carotid ultrasonography in the detection of early extracranial carotid atherosclerosis
Large-gap insulating dimer ground state in monolayer IrTe2
Monolayers of two-dimensional van der Waals materials exhibit novel
electronic phases distinct from their bulk due to the symmetry breaking and
reduced screening in the absence of the interlayer coupling. In this work, we
combine angle-resolved photoemission spectroscopy and scanning tunneling
microscopy/spectroscopy to demonstrate the emergence of a unique insulating 2 x
1 dimer ground state in monolayer 1T-IrTe2 that has a large band gap in
contrast to the metallic bilayer-to-bulk forms of this material.
First-principles calculations reveal that phonon and charge instabilities as
well as local bond formation collectively enhance and stabilize a
charge-ordered ground state. Our findings provide important insights into the
subtle balance of interactions having similar energy scales that occurs in the
absence of strong interlayer coupling, which offers new opportunities to
engineer the properties of 2D monolayers
Intracoronary imaging in PCI for acute coronary syndrome: Insights from British Cardiovascular Intervention Society registry
Background: While previous studies have demonstrated the superiority of ICI-guided PCI over an angiography-based approach, there are limited data on all-comer ACS patients. This study aimed to identify the characteristics and in-hospital outcomes of patients undergoing intracoronary imaging (ICI) guided percutaneous coronary intervention (PCI) for acute coronary syndrome (ACS). Methods: All patient undergoing PCI for ACS in England and Wales between 2006 and 2019 were retrospectively analyzed and stratified according to ICI utilization. The outcomes assessed were in-hospital all-cause mortality and major adverse cardiovascular and cerebrovascular events (MACCE) using multivariable logistic regression models. Results: 598,921 patients underwent PCI for ACS, of which 41,716 (7.0 %) had ICI which was predominantly driven by IVUS use (5.6 %). ICI use steadily increased from 1.4 % in 2006 to 13.5 % in 2019. Adjusted odds of mortality (OR 0.69, 95%CI 0.58–0.83) and MACCE (OR 0.77, 95%CI 0.73–0.83) were significantly lower in the ICI group. The association between ICI and improved outcomes varied according to vessel treated with both left main stem (LMS) and LMS/left anterior descending (LAD) PCI associated with significantly lower odds of mortality (OR 0.34, 95%CI 0.27–0.44, OR 0.51 95%CI 0.45–0.56) and MACCE (OR 0.44 95%CI 0.35–0.54, OR 0.67 95%CI 0.62–0.72) respectively. Conclusions: Although ICI use has steadily increased, less than one in seven patients underwent ICI-guided PCI. The association between ICI use and improved in-hospital outcomes was mainly observed in PCI procedures involving LMS and LAD
Impact of COVID-19 on cardiac procedure activity in England and associated 30-day mortality
BACKGROUND: Limited data exists on the impact of COVID-19 on national changes in cardiac procedure activity, including patient characteristics and clinical outcomes before and during the COVID-19 pandemic. METHODS AND RESULTS: All major cardiac procedures (n = 374,899) performed between 1st January and 31st May for the years 2018, 2019 and 2020 were analysed, stratified by procedure type and time-period (pre-COVID: January-May 2018 and 2019 and January-February 2020 and COVID: March-May 2020). Multivariable logistic regression was performed to examine the odds ratio (OR) of 30-day mortality for procedures performed in the COVID period.Overall, there was a deficit of 45,501 procedures during the COVID period compared to the monthly averages (March-May) in 2018-2019. Cardiac catheterisation and device implantations were the most affected in terms of numbers (n = 19,637 and n = 10,453) whereas surgical procedures such as MVR, other valve replacement/repair, ASD/VSD repair and CABG were the most affected as a relative percentage difference (Δ) to previous years' averages. TAVR was the least affected (Δ-10.6%). No difference in 30-day mortality was observed between pre-COVID and COVID time-periods for all cardiac procedures except cardiac catheterisation (OR 1.25 95% confidence interval (CI) 1.07-1.47, p = 0.006) and cardiac device implantation (OR 1.35 95% CI 1.15-1.58, p < 0.001). CONCLUSION: Cardiac procedural activity has significantly declined across England during the COVID-19 pandemic, with a deficit in excess of 45000 procedures, without an increase in risk of mortality for most cardiac procedures performed during the pandemic. Major restructuring of cardiac services is necessary to deal with this deficit, which would inevitably impact long-term morbidity and mortality
- …