Cell-Set Modelling for a Microtab Implementation on a DU91W(2)250 Airfoil

Microtabs (MTs) are a regularly used flow control device in terms of wind turbine optimization. The present study introduces the application of the novel cell-set model for an MT implementation on a DU91W(2)250 airfoil. The cell-set model is based on the reusability of a mesh to add new geometries on the domain; the matching geometry is located where the user requires, and a set of cells is constructed around the mentioned geometry. Subsequently, wall boundaries are assigned to the generated region. Computational simulations were carried out for fully mesh and cell-set models: MT lengths were set at 1.0%, 1.5% and 2.0% of the airfoil chord length (c) and the MTs were placed at 93% and 95% of c from the leading edge of the airfoil. Resulting data showed that the MT behavior was similar for both models with regard to aerodynamic performance curve representations. A global relative error of 3.784% was obtained for the cell-set model and a maximum relative error of 7.332% was determined. Qualitatively, both models generated significantly similar flow stream velocity wakes on the trailing edge area of the airfoil.The authors appreciate the support of the government of the Basque Country and the University of the Basque Country UPV/EHU through SAIOTEK (S-PE11UN112), EHU12/26, Grant N. ELKARTEK 20/71 and ELKARTEK 20/78 research programs

Astrocytes and Inflammatory Processes in Alzheimer’s Disease

A significant increase in inflammation has been shown to be a crucial factor in the progression of the Alzheimer’s disease (AD). Moreover, inflammatory signals are already present in mild cognitive impairment (MCI) patients before they develop AD. The amyloid hypothesis argues that in AD, there is an increase in oxidative stress caused by the accumulation of β-amyloid (Aβ) and that its elimination should be a priority. Also, hyperphosphorylation of the protein TAU occurs, which is characteristic of this disease. In AD oxidative stress processes occur and also inflammation. The basal chronic inflammation produces a cascade of cellular, such as astrocytes and microglial cells, and molecular processes in AD patients. We here have tried to explore the action of the inflammatory process and its implication in the neurodegenerative process of the AD. We can see that the role of Aβ is only one component that gives rise to inflammation, probably mediated by activation of microglia and astrocytes with the goal of getting rid of these brain waste products. In fact, it is related to a greater degree with the progression of the disease and worsening of the symptoms with the increase of phosphorylated TAU in different parts of the brain

Function of Glia in Aging and the Brain Diseases.

Microglia cells during aging, neurodegeneration and neuroinflammation show different morphological and transcriptional profiles (related to axonal direction and cell adhesion). Furthermore, expressions of the receptors on the surface and actin formation compared to young are also different. This review delves into the role of glia during aging and the development of the diseases. The susceptibility of different regions of the brain to disease are linked to the overstimulation of signals related to the immune system during aging, as well as the damaging impact of these cascades on the functionality of different populations of microglia present in each region of the brain. Furthermore, a decrease in microglial phagocytosis has been related to many diseases and also has been detected during aging. In this paper we also describe the role of glia in different illness, such as AD, ALS, pain related disorders, cancer, developmental disorders and the problems produced by opening of the blood brain barrier. Future studies will clarify many points planted by this review

AVALIAÇÃO DE SENSORES DE RESISTÊNCIA ELÉTRICA E TENSIÔMETROS COM TRANSDUTORES DE TENSÃO PARA DETERMINAÇÃO DO POTENCIAL DE ÁGUA DO SOLO

Electronic sensors have been increasingly used for soil water measurement, which is important for plant growth and for rational water use. The aim of the present study was to assess the performance of electrical resistance sensors (SRE) comparatively to tensiometers equipped with tension transducers (TT). TT’s coupled to 0.3-meter-long tensiometers were assembled on porous plates and submitted to increasing tensions ranging from 1 to 14,5 kPa. Both TT’s and SRE were installed in a box containing an air-dried fine earth sample of a red latosol, which was saturated with water and air-dried. The soil was then saturated with a potassium chloride solution. Finally, sensors were installed in the field for a fourmonth period. The results revealed the values showed a difference of 3 kPa and that salinity did not affect significantly the correlation between the data obtained from both sensors. Both SRE and TT’s showed similar performance in the wet range where the experiment was carried out and in the field, being quite useful to monitor soil water content.A utilização de sensores eletrônicos para determinação do potencial de água no solo tem sido cada vez maior, pela importância que esse monitoramento representa para o desenvolvimento das plantas e uso racional da água. Com o objetivo de avaliar o comportamento de sensores de resistência elétrica (SRE) em comparação com tensiômetros equipados com transductores de tensão (TT) realizou-se esse trabalho. Os TT acoplados a tensiômetros com 0,3 m de comprimento foram instalados em funis de placa porosa, e submetidos a tensões crescentes de 1 a 14,5 kPa. Os TT e os SRE foram instalados em uma caixa contendo TFSA de Latossolo Vermelho, que foi saturado, posto a secar ao ambiente e novamente saturado com solução de cloreto de potássio. Em uma última etapa os sensores foram instalados no campo por um período de quatro meses. Os resultados demonstraram que ocorreu uma diferença entre a tensão aplicada nos funis de placa porosa e a medida de 3 kPa e que a salinidade não afetou de forma significativa a correlação entre os resultados dos dois sensores avaliados, na faixa de umidade em que esse experimento foi conduzido e no campo se comportaram de forma similar. Nas condições em que o trabalho foi desenvolvido, os dois sensores tiveram um bom desempenho para determinar o potencial de água no solo

Action of low doses of Aspirin in Inflammation and Oxidative Stress induced by aβ1-42 on Astrocytes in primary culture

Aspirin has been used as anti-inflammatory and anti-aggregate for decades but the precise mechanism(s) of action after the presence of the toxic peptide Aβ1-42 in cultured astrocytes remains poorly resolved. Here we use low-doses of aspirin (10-7 M) in astrocytes in primary culture in presence or absence of Aβ1-42 toxic peptide. We noted an increase of cell viability and proliferation with or without Aβ1-42 peptide presence in aspirin treated cells. In addition, a decrease in apoptosis, determined by Caspase 3 activity and the expression of Cyt c and Smac/Diablo, were detected. Also, aspirin diminished necrosis process (LDH levels), pro-inflammatory mediators (IL-β and TNF-α) and NF-ᴋB protein expression, increasing anti-inflammatory PPAR-γ protein expression, preventing Aβ1-42 toxic effects. Aspirin inhibited COX-2 and iNOS without changes in COX-1 expression, increasing anti-oxidant protein (Cu/Zn-SOD and Mn-SOD) expression in presence or absence of Aβ1-42. Taken together, our results show that aspirin, at low doses increases cell viability by decreasing inflammation and oxidative stress, preventing the deleterious effects of the Aβ1-42 peptide on astrocytes in primary culture. The use of low doses of aspirin may be more suitable for Alzheimer's disease

Velocidade de semeadura de trigo sob sistema plantio direto

Several factors, such as operating speed, seeding depth, and soil moisture, can interfere with the implementation and establishment of crops during seeding, affecting their yield. This work aimed to assess the performance of two drillers, SDM 2023 from Metasa, with and without depth control wheels, and SHM 15 from Semeato, at different operating speeds. Seed distribution, seeding depth, percentage of soil surface covered with crop residues, wheat grain yield and yield components, were evaluated, using two experiments conducted on a typically dystrophic oxisol under no tillage. Wheat grain yield and yield components were not affected by treatments. The use of depth control wheels at the highest seeding speed (13.5 km h-1) increased the percentage of crop residues incorporated into the soil. High seeding speeds increased the operating capacity of drillers. However, it is important that the speeds are adequate for straw-cutting and furrowing operation to prevent wheat grain yield decrease.Diversos fatores, como a velocidade de operação, a profundidade de semeadura e o teor de água no solo, interferem na implantação e no estabelecimento das culturas durante a semeadura, podendo afetar a sua produtividade. O objetivo desse trabalho foi avaliar o desempenho de duas semeadoras-adubadoras operadas em diferentes velocidades. As semeadoras avaliadas foram a SDM 2023 da Metasa, com e sem limitador de profundidade, e a SHM 15 da Semeato. Avaliou-se a distribuição das sementes, a profundidade de semeadura, o percentual da superfície do solo coberta com restos culturais, o rendimento de grãos e seus componentes da cultura do trigo, em dois experimentos instalados num Latossolo Vermelho distrófico típico sob plantio direto. O rendimento de grãos e componentes não foram afetados pelos tratamentos utilizados. Com relação ao percentual de cobertura do solo por restos culturais no equipamento, com o uso de limitadores de profundidade, utilizando a maior velocidade de semeadura (13,5 km.h-1), ocorreu maior incorporação dos restos culturais. Conclui-se que velocidades de semeadura elevadas acarretam em maior capacidade operacional das semeadoras-adubadoras. Elas não afetam o rendimento de grãos de trigo, desde que a sua condução seja adequada à capacidade de corte de palha e de abertura de sulcos pelos seus mecanismos no solo

Neuronal effects of Sugammadex in combination with Rocuronium or Vecuronium.

Rocuronium (ROC) and Vecuronium (VEC) are the most currently used steroidal non-depolarizing neuromuscular blocking (MNB) agents. Sugammadex (SUG) rapidly reverses steroidal NMB agents after anaesthesia. The present study was conducted in order to evaluate neuronal effects of SUG alone and in combination with both ROC and VEC. Using MTT, CASP-3 activity and Western-blot we determined the toxicity of SUG, ROC or VEC in neurons in primary culture. SUG induces apoptosis/necrosis in neurons in primary culture and increases cytochrome C (CytC), apoptosis-inducing factor (AIF), Smac/Diablo and Caspase 3 (CASP-3) protein expression. Our results also demonstrated that both ROC and VEC prevent these SUG effects. The protective role of both ROC and VEC could be explained by the fact that SUG encapsulates NMB drugs. In BBB impaired conditions it would be desirable to control SUG doses to prevent the excess of free SUG in plasma that may induce neuronal damage. A balance between SUG, ROC or VEC would be necessary to prevent the risk of cell damag

Sugammadex, a neuromuscular blockade reversal agent, causes neuronal apoptosis in primary cultures.

Sugammadex, a γ-cyclodextrin that encapsulates selectively steroidal neuromuscular blocking agents, such as rocuronium or vecuronium, has changed the face of clinical neuromuscular pharmacology. Sugammadex allows a rapid reversal of muscle paralysis. Sugammadex appears to be safe and well tolerated. Its blood-brain barrier penetration is poor (< 3% in rats), and thus no relevant central nervous toxicity is expected. However the blood brain barrier permeability can be altered under different conditions (i.e. neurodegenerative diseases, trauma, ischemia, infections, or immature nervous system). Using MTT, confocal microscopy, caspase-3 activity, cholesterol quantification and Western-blot we determine toxicity of Sugammadex in neurons in primary culture. Here we show that clinically relevant sugammadex concentrations cause apoptotic/necrosis neuron death in primary cultures. Studies on the underlying mechanism revealed that sugammadex-induced activation of mitochondria- dependent apoptosis associates with depletion of neuronal cholesterol levels. Furthermore SUG increase CytC, AIF, Smac/Diablo and CASP-3 protein expression in cells in culture. Potential association of SUG-induced alteration in cholesterol homeostasis with oxidative stress and apoptosis activation occurs. Furthermore, resistance/sensitivity to oxidative stress differs between neuronal cell types

WIN 55,212-2, agonist of cannabinoid receptors, prevents amyloid β1-42 effects on astrocytes in primary culture

Alzheimer´s disease (AD), a neurodegenerative illness involving synaptic dysfunction with extracellular accumulation of Aβ1-42 toxic peptide, glial activation, inflammatory response and oxidative stress, can lead to neuronal death. Endogenous cannabinoid system is implicated in physiological and physiopathological events in central nervous system (CNS), and changes in this system are related to many human diseases, including AD. However, studies on the effects of cannabinoids on astrocytes functions are scarce. In primary cultured astrocytes we studied cellular viability using MTT assay. Inflammatory and oxidative stress mediators were determined by ELISA and Westernblot techniques both in the presence and absence of Aβ1-42 peptide. Effects of WIN 55,212-2 (a synthetic cannabinoid) on cell viability, inflammatory mediators and oxidative stress were also determined. Aβ1-42 diminished astrocytes viability, increased TNF-α and IL-1β levels and p-65, COX-2 and iNOS protein expression while decreased PPAR-γ and antioxidant enzyme Cu/Zn SOD. WIN 55,212-2 pretreatment prevents all effects elicited by Aβ1-42. Furthermore, cannabinoid WIN 55,212-2 also increased cell viability and PPAR-γ expression in control astrocytes. In conclusion cannabinoid WIN 55,212-2 increases cell viability and anti-inflammatory response in cultured astrocytes. Moreover, WIN 55,212-2 increases expression of anti-oxidant Cu/Zn SOD and is able to prevent inflammation induced by Aβ1-42 in cultured astrocytes. Further studies would be needed to assess the possible beneficial effects of cannabinoids in Alzheimer's disease patients

Astrocytes protect neurons from Aβ1-42 peptide-induced neurotoxicity increasing TFAM and PGC-1 and decreasing PPAR-γ and SIRT-1.

One of the earliest neuropathological events in Alzheimer¿s disease is accumulation of astrocytes at sites of Aβ1-42 depositions. Our results indicate that Aβ1-42 toxic peptide increases lipid peroxidation, apoptosis and cell death in neurons but not in astrocytes in primary culture. Aβ1-42-induced deleterious neuronal effects are not present when neurons and astrocytes are mixed cultured. Stimulation of astrocytes with toxic Aβ1-42 peptide increased p-65 and decreased IκB resulting in inflammatory process. In astrocytes Aβ1-42 decreases protein expressions of sirtuin 1 (SIRT-1) and peroxisome proliferator-activated receptor γ (PPAR-γ) and over-expresses peroxisome proliferator-activated receptor γ coactivator 1 (PGC-1) and mitochondrial transcription factor A (TFAM), protecting mitochondria against Aβ1-42-induced damage and promoting mitochondrial biogenesis. In summary our data suggest that astrocytes may have a key role in protecting neurons, increasing neural viability and mitochondrial biogenesis, acquiring better oxidative stress protection and perhaps modulating inflammatory processes against Aβ1-42 toxic peptide. This might be a sign of a complex epigenetic process in Alzheimer¿s disease development