Piezoelectric Energy Harvesting Suspension System for a Half Car Model: Analytical and Experimental Study

One of the essential techniques for energy harvesting is the clean energy collection from ambient vibration. Recently, piezoelectric energy harvesting systems became a hot topic and attracted many researchers. This is due to their simple structure, relatively high output power among the other mechanisms (electromagnetic and electrostatic), compatibility with MEMS, and operation in a wide frequency range. The main objective of the current work is to develop a mathematical model to evaluate the potential of harvesting power from the car suspension system. Quarter and half car models with a built-in piezoelectric stack were modeled mathematically using Laplace transformation and simulated using MATLAB/Simulink. The piezoelectric stack was installed in series with the suspension spring to maintain the performance of the original suspension system in ride quality and comfortability. The harvested voltage and power were tested in both time and frequency domain approaches. The results from a quarter car model showed that, the maximum generated voltage and power under harmonic excitation with an acceleration amplitude of 0.5 g and frequency of 1.46 Hz were 19.11 V and 36.74 mW, respectively. By comparing the quarter car model with a half car model, the results illustrated that the output voltage and power of the half car models were increased to 33.56 V and 56.35 mW (75.6% and 53.4%), respectively. Furthermore, the quarter and half car models were subjected to random excitation and tested under three different road classes (A, C, and H). The findings confirmed that the harvested voltage and power were increased with the road roughness levels and car velocity. From very smooth to very rough road levels, the harvested power was increased by 434 mW for quarter car model and 537 mW for half car model. The influence of the different parameters of the piezoelectric stack (number of stack layers and area to thickness) and car suspension (sprung and unsprung stiffness, damping coefficients, and masses) were examined for half car model subjected to harmonic excitation. Also, the effect of road amplitude unevenness was considered. The analytical results of the quarter car model were verified with the experimental test under harmonic excitation. The results exhibited good agreement with the analytical results at different excitation frequencies (0 – 25 Hz). A significant contribution of this work is developing a half car model with a built-in piezoelectric stack. The findings of this work illustrated that there is a significant potential for harvesting energy from the car suspension system. This energy could be utilized in different ways. The study will encourage automobile manufacturers to develop and produce cars that are equipped with multiple energy harvesters to make the dissipated energy available for utilization. Such utilization of regenerated energy improves the fuel efficiency and the economy significantly

In vitro investigations on biological activities and bioaccessibility of rosehip carotenoids

Recent developments in the fields of health and food have led to a renewed interest in natural compounds with antioxidant potential. A diet rich in antioxidant components has potential effects on the human health by reducing the risk of various diseases, for example cardiovascular diseases, cancers and age-related macular degeneration [1]. The selection of species/varieties with high contents of bioactive compounds and harvesting at the optimum time can promote the increase in the uptake of bioactive compounds from the fruits and vegetables. In recent decades, the rosehip fruit has been increasingly studied for its medical properties. The hips of Rosa species have received more attention in recent years due to their high contents of antioxidants. Genus Rosa contains over 100 species, which are widespread and different in their appearance as well as in the chemical composition. Although Rosa rugosa is known to produce the most abundant and best tasting hips, most food products are based on the hips of R. canina, although they are small compared with the R. rugosa hips [2]. On the other hand, the limited bioavailability of antioxidants present in food from fruit and vegetable matrices is determined by their low bioaccessibility due to the physical and chemical interactions of the antioxidants with the indigestible polysaccharides of cell walls. Bioaccessibility is defined as the fraction of a compound that releases from its matrix in the gastrointestinal tract and thus becomes available for intestinal absorption [3-5]. However, human intervention studies to assess intestinal absorption are expensive, often invasive, and of long duration. Static in vitro models based on human physiology were developed as simple, inexpensive, and reproducible tools to predict the bioavailability of different food components. Although rosehips have more recently attracted attention because of their potential health benefits, there is little information about the change of antioxidants contents in different rosehip products as well as depending on the degree of ripeness, especially in rugosa hips. Furthermore, there is no study having investigated the bioaccessibility of carotenoids and vitamin E from rosehip raw materials as well as its products. ..

Targeting AnxA1/Fpr2/ALX Regulates Neutrophil Function Promoting Thrombo-Inflammation Resolution in Sickle Cell Disease

NIH/NHLBI (HL134959-01A1 [FNEG]; HL098435, HL133497, HL141155, and GM12130 [AWO]; HL142604 [RP]), the AHA (19PRE34380751 [ZAY]) and the Royal Society Wolfson Foundation (RSWF\R3\183001 [FNEG])

Novel Role for the AnxA1-Fpr2/ALX Signaling Axis as a Key Regulator of Platelet Function to Promote Resolution of Inflammation

Background: Ischemia reperfusion injury (I/RI) is a common complication of cardiovascular diseases. Resolution of detrimental I/RI-generated prothrombotic and proinflammatory responses is essential to restore homeostasis. Platelets play a crucial part in the integration of thrombosis and inflammation. Their role as participants in the resolution of thromboinflammation is underappreciated; therefore we used pharmacological and genetic approaches, coupled with murine and clinical samples, to uncover key concepts underlying this role. Methods: Middle cerebral artery occlusion with reperfusion was performed in wild-type or annexin A1 (AnxA1) knockout (AnxA1-/-) mice. Fluorescence intravital microscopy was used to visualize cellular trafficking and to monitor light/dye-induced thrombosis. The mice were treated with vehicle, AnxA1 (3.3 mg/kg), WRW4 (1.8 mg/kg), or all 3, and the effect of AnxA1 was determined in vivo and in vitro. Results: Intravital microscopy revealed heightened platelet adherence and aggregate formation post I/RI, which were further exacerbated in AnxA1-/- mice. AnxA1 administration regulated platelet function directly (eg, via reducing thromboxane B2 and modulating phosphatidylserine expression) to promote cerebral protection post-I/RI and act as an effective preventative strategy for stroke by reducing platelet activation, aggregate formation, and cerebral thrombosis, a prerequisite for ischemic stroke. To translate these findings into a clinical setting, we show that AnxA1 plasma levels are reduced in human and murine stroke and that AnxA1 is able to act on human platelets, suppressing classic thrombin-induced inside-out signaling events (eg, Akt activation, intracellular calcium release, and Ras-associated protein 1 [Rap1] expression) to decrease IIbβ3 activation without altering its surface expression. AnxA1 also selectively modifies cell surface determinants (eg, phosphatidylserine) to promote platelet phagocytosis by neutrophils, thereby driving active resolution. (n=5-13 mice/group or 7-10 humans/group.) Conclusions: AnxA1 affords protection by altering the platelet phenotype in cerebral I/RI from propathogenic to regulatory and reducing the propensity for platelets to aggregate and cause thrombosis by affecting integrin (IIbβ3) activation, a previously unknown phenomenon. Thus, our data reveal a novel multifaceted role for AnxA1 to act both as a therapeutic and a prophylactic drug via its ability to promote endogenous proresolving, antithromboinflammatory circuits in cerebral I/RI. Collectively, these results further advance our knowledge and understanding in the field of platelet and resolution biology.Fil: Senchenkova, Elena Y.. State University of Louisiana; Estados UnidosFil: Ansari, Junaid. State University of Louisiana; Estados UnidosFil: Becker, Felix. University Hospital Muenster; AlemaniaFil: Vital, Shantel A.. State University of Louisiana; Estados UnidosFil: Al-Yafeai, Zaki. State University of Louisiana; Estados UnidosFil: Sparkenbaugh, Erica M.. University North Carolina Chapel Hill; Estados UnidosFil: Pawlinski, Rafal. University North Carolina Chapel Hill; Estados UnidosFil: Stokes, Karen Y.. State University of Louisiana; Estados UnidosFil: Carroll, Jennifer L.. State University of Louisiana; Estados UnidosFil: Dragoi, Ana-Maria. State University of Louisiana; Estados UnidosFil: Qin, Cheng Xue. Baker Heart And Diabetes Institute; AustraliaFil: Ritchie, Rebecca H.. Baker Heart And Diabetes Institute; AustraliaFil: Sun, Hai. University Hospital Muenster; AlemaniaFil: Cuellar-Saenz, Hugo H.. State University of Louisiana; Estados UnidosFil: Rubinstein Guichon, Mara Roxana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas; Argentina. Columbia University; Estados UnidosFil: Han, Yiping W.. Columbia University; Estados UnidosFil: Orr, A. Wayne. University Hospital Muenster; AlemaniaFil: Perretti, Mauro. Queen Mary University Of London; Reino UnidoFil: Granger, D. Neil. State University of Louisiana; Estados UnidosFil: Gavins, Felicity N.E.. State University of Louisiana; Estados Unido

Bioactive Compounds and Antioxidant Capacity of Rosa rugosa Depending on Degree of Ripeness

Maturity stage affects the bioactive compounds as well as the antioxidant capacity in the fruit. This study was designed to identify and quantify carotenoids, as well as to evaluate vitamin E, vitamin C, antioxidant capacity and total phenolic compounds of Rosa rugosa hips at different degrees of ripeness. HPLC (high performance liquid chromatography) analysis showed different types of carotenoids at different stages of maturity of R. rugosa hips with significant differences (p ˂ 0.05), where the maximum concentration was observed at late harvesting. In the hips investigated, only α-tocopherol was detected, the maximum concentration of both vitamin E and vitamin C was obtained in the orange hips with significant difference (p ˂ 0.05). On the other hand, the highest hydrophilic and lipophilic TEAC (Trolox equivalent antioxidant capacity) values, as well as total phenolic contents, were determined in the mature hips (red colour) with significant difference (p < 0.0001) and (p < 0.001) respectively, whereas ORAC (oxygen radical absorbance capacity) showed lower activity in the mature hips with significant difference (p ˂ 0.05). Late harvesting is recommended if a high content of carotenoids is desired, while harvesting should be carried out earlier if a higher vitamin E and vitamin C content is desired, which in turn affects the antioxidants capacity

Bioactive Compounds and Antioxidant Capacity of Rosa rugosa Depending on Degree of Ripeness

Maturity stage affects the bioactive compounds as well as the antioxidant capacity in the fruit. This study was designed to identify and quantify carotenoids, as well as to evaluate vitamin E, vitamin C, antioxidant capacity and total phenolic compounds of Rosa rugosa hips at different degrees of ripeness. HPLC (high performance liquid chromatography) analysis showed different types of carotenoids at different stages of maturity of R. rugosa hips with significant differences (p ˂ 0.05), where the maximum concentration was observed at late harvesting. In the hips investigated, only α-tocopherol was detected, the maximum concentration of both vitamin E and vitamin C was obtained in the orange hips with significant difference (p ˂ 0.05). On the other hand, the highest hydrophilic and lipophilic TEAC (Trolox equivalent antioxidant capacity) values, as well as total phenolic contents, were determined in the mature hips (red colour) with significant difference (p < 0.0001) and (p < 0.001) respectively, whereas ORAC (oxygen radical absorbance capacity) showed lower activity in the mature hips with significant difference (p ˂ 0.05). Late harvesting is recommended if a high content of carotenoids is desired, while harvesting should be carried out earlier if a higher vitamin E and vitamin C content is desired, which in turn affects the antioxidants capacity

Adverse events related to AtriCure EPi-Sense Coagulation Device-Analysis of the FDA MAUDE database

INTRODUCTION: The AtriCure EPi-Sense Device is used for the hybrid convergent procedure, an emerging treatment for persistent atrial fibrillation (AF) and long-standing persistent AF. However, data on the AE related to the EPi-Sense device are scarce. METHODS: Keyword EPI-SENSE was searched on the MAUDE database. There were 80 device reports from 2016 to 2020. After excluding reports when the device was not returned for evaluation, 79 device reports were included for final analysis. RESULTS: The adverse events (AE) were broadly classified into 11 categories. The most common complications were pericardial effusion (25.3%), stroke (17.7%), and atrioesophageal fistula (AEF) (8.9%). Death was reported in 15 (19%) cases, 3 of which were due to pulmonary embolism, 6 due to AEF, 3 due to unknown cause, 1 due to sepsis, 2 due to events related to acute renal failure. DISCUSSION: Pericardial effusion is a common AE reported in patients with convergence procedures and is well documented in the CONVERGE trial. The convergent procedure is unique in that the epicardial ablations are performed on the posterior wall with the radiofrequency probe directed towards the heart and away from the esophagus which in theory should reduce esophageal injuries. Despite that, a high number of AEF were noticed. Finally, there were also some reports of saline perfusion malfunction which can lead to injuries due to overheating. CONCLUSION: This analysis of the AE related to the EPi-Sense device highlights several major AE that are previously unreported