Academic literature on the topic 'Oscillatory flow stimulation'
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Journal articles on the topic "Oscillatory flow stimulation"
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Zhang, Xiao, Yan Gao, and Bo Huo. "Finite Element Analysis on Wall Fluid Shear Stress on Cells under Oscillatory Flow." Applied Sciences 11, no. 21 (October 26, 2021): 10021. http://dx.doi.org/10.3390/app112110021.
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During mechanical stimulation-induced bone remodeling, interstitial fluid around microcracks may produce a flow field with gradient fluid shear stress (FSS). Osteoclast precursors can sense this gradient FSS and migrate toward the low FSS region. However, the local distribution of wall FSS on bone cells under a flow field with globally gradient FSS remains unknown. In this study, finite element models of a modified plate flow chamber with cells were constructed. The effect of oscillatory flow with different FSS levels and cell spacings or frequencies on the distribution of local wall FSS around cells was simulated by using a fluid–solid coupling method. Results showed that the polarization of wall FSS distribution in a cell decreased with the increase in cell spacing. At a low FSS level, the frequency of oscillatory flow had a minimal effect on the wall FSS distribution. At a high FSS level, the increase in flow frequency enhanced the fluctuation of local wall FSS distribution on cells. These results provide a basis for future research on the flow-induced migration of osteoclast precursors and clarify the mechanism of mechanical stimulation-induced bone resorption.
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Gavriely, N., J. Solway, J. M. Drazen, A. S. Slutsky, R. Brown, S. H. Loring, and R. H. Ingram. "Radiographic visualization of airway wall movement during oscillatory flow in dogs." Journal of Applied Physiology 58, no. 2 (February 1, 1985): 645–52. http://dx.doi.org/10.1152/jappl.1985.58.2.645.
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It has been suggested that radial movement of the central airway walls during oscillatory flow might contribute to the increased frequency dependence of compliance seen in chronic obstructive pulmonary disease (COPD) (J. Appl. Physiol. 26: 670–677, 1969). Radial airway wall motion has also been invoked to explain the frequency-dependent decreases in the efficiency of gas exchange during low-volume high-frequency ventilation (HFV) in histamine-bronchoconstricted dogs and in patients with respiratory insufficiency. To test the possibility that airway wall motion increases with bronchoconstriction, we measured central airway diameters using cinebronchoradiography in anesthetized tracheostomized dogs during oscillatory HFV [50 and 100 ml tidal volume (VT) at frequencies (f) of 2, 6, and 12 Hz], under control conditions, during electrical stimulation of the vagi, and after exposure to histamine aerosol. Cineradiobronchograms from two dogs were evaluated quantitatively for tracheal diameter and for lengths and diameters of a number of major airways. Under control conditions, the diameter of the airways fluctuated 7–9% of the mean with VT of 50 ml and 9–18% with VT of 100 ml in the range of frequencies studied. Bronchoconstriction produced by aerosolized histamine increased radial airway wall movement to 10–47% with VT of 50 ml, and during vagal stimulation diameters changed 7–20% at VT of 50 ml. After histamine, the central airways displayed large diameter changes during HFV, whereas more peripheral airways were markedly constricted and did not change in diameter.
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Shivaram, Giridhar M., Chi Hyun Kim, Nikhil N. Batra, Wuchen Yang, Stephen E. Harris, and Christopher R. Jacobs. "Novel early response genes in osteoblasts exposed to dynamic fluid flow." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 368, no. 1912 (February 13, 2010): 605–16. http://dx.doi.org/10.1098/rsta.2009.0231.
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Cyclic mechanical loads applied to the skeleton from habitual physical activity result in increased bone formation. These loads lead to dynamic pressure gradients and oscillatory flow of bone interstitial fluid, which, in turn, exposes cells resident in the bony matrix to oscillatory fluid shear stress. Dynamic fluid flow has previously been shown to be a potent anabolic stimulus for cultured osteoblasts. In this study, we used cDNA microarrays to examine early phase, broad-spectrum gene expression in MC3T3-E1 osteoblasts in response to physical stimulation. RNA was harvested at 30 min and 1 h post-stimulation. RNA was used for microarray hybridization as well as subsequent reverse transcription polymerase chain reaction (RT-PCR) validation of expression levels for selected genes. Microarray results were analysed by both functional and expression profile clustering. We identified a small number of genes at both the 30 min and 1 h timepoints that were either upregulated or downregulated with flow compared to no-flow control by twofold or more. From the group of genes upregulated at 30 min, we selected nine for RT-PCR confirmation. All were found to be upregulated by at least twofold. We identify a novel set of early response genes potentially involved in mediating the anabolic response of MC3T3 osteoblasts to flow, and provide functional groupings of these genes that may shed light on the relevant mechanosensory pathways involved.
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Grudzińska, Ewa, Andrzej Lekstan, Ewelina Szliszka, and Zenon P. Czuba. "Cytokines Produced by Lymphocytes in the Incompetent Great Saphenous Vein." Mediators of Inflammation 2018 (June 14, 2018): 1–8. http://dx.doi.org/10.1155/2018/7161346.
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The pathogenesis of chronic venous disease (CVD) remains unclear, but lately inflammation is suggested to have an important role in its development. This study is aimed at assessing cytokines released by lymphocytes in patients with great saphenous vein (GSV) incompetence. In 34 patients exhibiting oscillatory flow (reflux) in GSV, blood was derived from the cubital vein and from the incompetent sapheno-femoral junction. In 12 healthy controls, blood was derived from the cubital vein. Lymphocyte culture with and without stimulation by phytohemagglutinin (PHA) was performed. Interleukins (IL) 1β, 2, 4, 10, 12 (p70), and 17A; interleukin 1 receptor α (IL-1ra); tumor necrosis factor-α (TNF-α); interferon-gamma (IFN-γ); and RANTES were assessed in culture supernatants by the Bio-Plex assay. In both stimulated and unstimulated samples, in the examined group, IL-1β and IFN-γ had higher concentrations and RANTES had lower concentrations when compared to those in the control group. In the examined group, IL-4 and IL-17A had higher concentrations without stimulation and TNF-α had higher concentrations with stimulation. The GSV samples had higher IL-2, IL-4, IL-12 (p70), and IFN-γ concentrations without stimulation and lower IL-2 and TNF-α concentrations with stimulation when compared to those of the upper limb in the examined group. These observations indicate that the oscillatory flow present in incompetent veins causes changes in the cytokine production by lymphocytes, promoting a proinflammatory profile. However, the relations between immunological cells, cytokines, and the endothelium require more insight.
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Xing, Yanghui, Liang Song, Yingying Zhang, Tengyu Zhang, Jian Li, and Chunjing Tao. "Purinergic Signaling Mediates PTH and Fluid Flow-Induced Osteoblast Proliferation." BioMed Research International 2021 (January 27, 2021): 1–8. http://dx.doi.org/10.1155/2021/6674570.
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Both parathyroid hormone (PTH) and mechanical signals are able to regulate bone growth and regeneration. They also can work synergistically to regulate osteoblast proliferation, but little is known about the mechanisms how PTH and mechanical signals interact with each other during this process. In this study, we investigated responses of MC3T3-E1 osteoblasts to PTH and oscillatory fluid flow. We found that osteoblasts are more sensitive to mechanical signals in the presence of PTH according to ERK1/2 phosphorylation, ATP release, CREB phosphorylation, and cell proliferation. PTH may also reduce the osteoblast refractory period after desensitization due to mechanical signals. We further found that the synergistic responses of osteoblasts to fluid flow or ATP with PTH had similar patterns, suggesting that synergy between fluid flow and PTH may be through the ATP pathway. After we inhibited ATP effects using apyrase in osteoblasts, their synergistic responses to mechanical stimulation and PTH were also inhibited. Additionally, knocking down P2Y2 purinergic receptors can significantly attenuate osteoblast synergistic responses to mechanical stimulation and PTH in terms of ERK1/2 phosphorylation, CREB phosphorylation, and cell proliferation. Thus, our results suggest that PTH enhances mechanosensitivity of osteoblasts via a mechanism involving ATP and P2Y2 purinergic receptors.
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Stauss, H. M., P. B. Persson, A. K. Johnson, and K. C. Kregel. "Frequency-response characteristics of autonomic nervous system function in conscious rats." American Journal of Physiology-Heart and Circulatory Physiology 273, no. 2 (August 1, 1997): H786—H795. http://dx.doi.org/10.1152/ajpheart.1997.273.2.h786.
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To characterize the efferent pathway from the hypothalamic paraventricular nucleus (PVN) to peripheral autonomic neurons and finally to selected effector organs, we stimulated the PVN in 10 conscious rats at frequencies ranging from 0.05 to 2.0 Hz. Simultaneously, blood pressure, heart rate, splanchnic sympathetic nerve activity, and mesenteric artery blood flow were measured. The sinus node of the heart responded to PVN stimulation via the parasympathetic pathway (during beta 1-adrenergic blockade) up to a stimulation frequency of 2.0 Hz, whereas the sympathetically mediated response (during muscarinic blockade) was limited to stimulation frequencies < 0.5 Hz. The splanchnic nerve responded to PVN stimulation with synchronous discharges up to stimulation frequencies of 2.0 Hz, whereas the oscillatory component of the vasoconstrictor response of the mesenteric artery was negligible beyond stimulation frequencies of 1.0 Hz. We conclude that sympathetic transmission to the heart is at least four times slower than parasympathetic transmission. In addition, the time-limiting step in sympathetic transmission from the hypothalamus to vascular smooth muscle contraction and pacemaker activity of the sinus node may be located at the site of synaptic transmission to the adrenergic receptors.
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Grudzińska, Ewa, Sławomir Grzegorczyn, and Zenon P. Czuba. "Chemokines and Growth Factors Produced by Lymphocytes in the Incompetent Great Saphenous Vein." Mediators of Inflammation 2019 (January 10, 2019): 1–10. http://dx.doi.org/10.1155/2019/7057303.
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The role of cytokines in the pathogenesis of chronic venous disease (CVD) remains obscure. It has been postulated that oscillatory flow present in incompetent veins causes proinflammatory changes. Our earlier study confirmed this hypothesis. This study is aimed at assessing chemokines and growth factors (GFs) released by lymphocytes in patients with great saphenous vein (GSV) incompetence. In 34 patients exhibiting reflux in GSV, blood was derived from the cubital vein and from the incompetent saphenofemoral junction. In 12 healthy controls, blood was derived from the cubital vein. Lymphocyte culture with and without stimulation by phytohemagglutinin (PHA) was performed. Eotaxin, interleukin 8 (IL-8), macrophage inflammatory protein 1 A and 1B (MIP-1A and MIP-1B), interferon gamma-induced protein (IP-10), monocyte chemoattractant protein-1 (MCP-1), interleukin 5 (IL-5), fibroblast growth factor (FGF), granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), platelet-derived growth factor-BB (PDGF-BB), and vascular endothelial growth factor (VEGF) were assessed in culture supernatants by a Bio-Plex assay. Higher concentrations of eotaxin and G-CSF were revealed in the incompetent GSV, compared with the concentrations in the patients’ upper limbs. The concentrations of MIP-1A and MIP-1B were higher in the CVD group while the concentration of VEGF was lower. In the stimulated cultures, the concentration of G-CSF proved higher in the incompetent GSV, as compared with the patients’ upper limbs. Between the groups, the concentration of eotaxin was higher in the CVD group, while the IL-5 and MCP-1 concentrations were lower. IL-8, IP-10, FGF, GM-CSF, and PDGF-BB did not reveal any significant differences in concentrations between the samples. These observations suggest that the concentrations of chemokines and GFs are different in the blood of CVD patients. The oscillatory flow present in incompetent veins may play a role in these changes. However, the role of cytokines in CVD requires further study.
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Sherwood, Joseph M., W. Daniel Stamer, and Darryl R. Overby. "A model of the oscillatory mechanical forces in the conventional outflow pathway." Journal of The Royal Society Interface 16, no. 150 (January 2019): 20180652. http://dx.doi.org/10.1098/rsif.2018.0652.
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Intraocular pressure is regulated by mechanosensitive cells within the conventional outflow pathway, the primary route of aqueous humour drainage from the eye. However, the characteristics of the forces acting on those cells are poorly understood. We develop a model that describes flow through the conventional outflow pathway, including the trabecular meshwork (TM) and Schlemm’s canal (SC). Accounting for the ocular pulse, we estimate the time-varying shear stress on SC endothelium and strain on the TM. We consider a range of outflow resistances spanning normotensive to hypertensive conditions. Over this range, the SC shear stress increases significantly and becomes highly oscillatory. TM strain also increases, but with negligible oscillations. Interestingly, TM strain responds more to changes in outflow resistance around physiological values, while SC shear stress responds more to elevated levels of resistance. A modest increase in TM stiffness, as observed in glaucoma, suppresses TM strain and practically eliminates the influence of outflow resistance on SC shear stress. As SC and TM cells respond to mechanical stimulation by secreting factors that modulate outflow resistance, our model provides insight regarding the potential role of SC shear and TM strain as mechanosensory cues for homeostatic regulation of outflow resistance and hence intraocular pressure.
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Malcolm, Brenda R., John J. Foxe, John S. Butler, Sophie Molholm, and Pierfilippo De Sanctis. "Cognitive load reduces the effects of optic flow on gait and electrocortical dynamics during treadmill walking." Journal of Neurophysiology 120, no. 5 (November 1, 2018): 2246–59. http://dx.doi.org/10.1152/jn.00079.2018.
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During navigation of complex environments, the brain must continuously adapt to both external demands, such as fluctuating sensory inputs, and internal demands, such as engagement in a cognitively demanding task. Previous studies have demonstrated changes in behavior and gait with increased sensory and cognitive load, but the underlying cortical mechanisms remain largely unknown. In the present study, in a mobile brain/body imaging (MoBI) approach, 16 young adults walked on a treadmill with high-density EEG while 3-dimensional (3D) motion capture tracked kinematics of the head and feet. Visual load was manipulated with the presentation of optic flow with and without continuous mediolateral perturbations. The effects of cognitive load were assessed by the performance of a go/no-go task on half of the blocks. During increased sensory load, participants walked with shorter and wider strides, which may indicate a more restrained pattern of gait. Interestingly, cognitive task engagement attenuated these effects of sensory load on gait. Using an independent component analysis and dipole-fitting approach, we found that cautious gait was accompanied by neuro-oscillatory modulations localized to frontal (supplementary motor area, anterior cingulate cortex) and parietal (inferior parietal lobule, precuneus) areas. Our results show suppression in alpha/mu (8–12 Hz) and beta (13–30 Hz) rhythms, suggesting enhanced activation of these regions with unreliable sensory inputs. These findings provide insight into the neural correlates of gait adaptation and may be particularly relevant to older adults who are less able to adjust to ongoing cognitive and sensory demands while walking. NEW & NOTEWORTHY The neural underpinnings of gait adaptation in humans are poorly understood. To this end, we recorded high-density EEG combined with three-dimensional body motion tracking as participants walked on a treadmill while exposed to full-field optic flow stimulation. Perturbed visual input led to a more cautious gait pattern with neuro-oscillatory modulations localized to premotor and parietal regions. Our findings show a possible brain-behavior link that might further our understanding of gait and mobility impairments.
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Bril, Ekaterina V., Elena M. Belova, Aleksey S. Sedov, Anna A. Gamaleya, Anna A. Poddubskaya, Natalia V. Fedorova, and Аleksey A. Tomskiy. "Current understanding of neurostimulation for Parkinson's disease." Annals of Clinical and Experimental Neurology 16, no. 2 (June 30, 2022): 89–99. http://dx.doi.org/10.54101/acen.2022.2.10.
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Specific mechanisms underlying the therapeutic effects of neurostimulation in Parkinson's disease remain a topic of discussion and intense study. Understanding these mechanisms can serve as the foundation for developing and selecting more effective parameters to relieve the symptoms of Parkinson's disease, maximize the advantages, and reduce the adverse effects and need for surgical intervention. The article discusses existing models of motor control in the basal ganglia in healthy individuals and in PD from the point of view of neuromodulation (changes in the impulse flow model, oscillatory model), as well as the current understanding of the mechanisms of action of deep brain stimulation (DBS): the block depolarization hypothesis, neural interference hypothesis, synaptic depression hypothesis, synaptic modulation hypothesis, and the DBS astrocytes hypothesis. Factors such as DBS location and neurostimulation parameters, affecting the clinical outcome, are considered in detail. The neuroprotective effect of DBS is also touched on.
Dissertations / Theses on the topic "Oscillatory flow stimulation"
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Zhang, Jia Ning. "The Effect of Mechanical Stimulation on Osteocyte Chemo-sensitivity." Thesis, 2012. http://hdl.handle.net/1807/33627.
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Osteocytes are believed to be the mechanosensory cells that detect and respond to mechanical loading. Physiological loading by oscillatory fluid flow (OFF) activates osteocytes to increase intracellular calcium concentration and release prostaglandin E2 (PGE2). Osteocytes are also sensitive to chemical stimulations such as serotonin, which can also increase PGE2 release. However, it is unclear whether mechanical stimulation can influence osteocyte sensitivity towards serotonin. In this thesis, MLO-Y4 osteocyte-like cells were subjected to serotonin with or without precondition by OFF, the responses of intracellular calcium and PGE2 release were measured. Serotonin increased intracellular calcium and PGE2 release in osteocytes. The effects were significantly reduced by OFF precondition, suggesting mechanical precondition by OFF can reduce osteocyte sensitivity towards serotonin. In terms of mechanisms, OFF- and serotonin-induced calcium responses depended on intra- and extracellular calcium stores. ATP was found to partially mediate OFF modulation of serotonin-induced PGE2 release but not calcium.
Conference papers on the topic "Oscillatory flow stimulation"
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Hu, M., J. Cheng, S. Ferreri, F. Serra-Hsu, W. Lin, and Y. X. Qin. "Induced Intramedullary Pressure by Dynamic Hydraulic Stimulation and Its Potential in Attenuation of Bone Loss." In ASME 2011 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2011. http://dx.doi.org/10.1115/sbc2011-54015.
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Bone loss is a critical health problem of astronauts in long-term space missions. A growing number of evidence has pointed out bone fluid flow as a critical regulator in mechanotransductive signaling and bone adaptation. Intramedullary pressure (ImP) is a key mediator for bone fluid flow initiation and it influences the osteogenic signals within the skeleton. The potential ImP-induced bone fluid flow then triggers bone adaptation [1]. Previous in vivo study has demonstrated that ImP induced by oscillatory electrical stimulations can effectively mitigate disuse osteopenia in a frequency-dependent manner in a disuse rat model [2, 3]. In order to develop the translational potentials of ImP, a non-invasive intervention with direct fluid flow coupling is necessary to develop new treatments for microgravity-induced osteopenia/osteoporosis.
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Qin, Y. X., M. Hu, F. Serra-Hsu, J. Cheng, S. Ferreri, Y. Huang, Z. K. Zhang, L. Lin, and D. Evangelista. "Local and Distant Intramedullary Pressure and Bone Strain by Dynamic Hydraulic Stimulation." In ASME 2011 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2011. http://dx.doi.org/10.1115/sbc2011-54017.
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Osteoporosis gives rise to fragile bones that have higher fracture risks due to diminished bone mass and altered bone microarchitecture [1]. Mechanical loading mediated bone adaptation has demonstrated promising potentials as a non-pharmacological alteration for both osteogenic response and attenuation of osteopenia [2]. Intramedullary pressure (ImP) has been proposed as a key factor for fluid flow initiation and mechanotransductive signal inductions in bone. It is also suggested that integration of strain signals over time allows low-level mechanical strain in the skeleton to trigger osteogenic activities. The potential bone fluid flow induced by strain and ImP mediates adaptive responses in the skeleton [3]. Previous in vivo studies using oscillatory electrical stimulations showed that dynamic muscle contractions can generate ImP and bone strain to mitigate disuse osteopenia in a frequency-dependent manner. To apply ImP alteration as a means for bone fluid flow regulation, it may be necessary to develop a new method that could couple external loading with internal bone fluid flow. In order to further study the direct effect of ImP on bone adaptation, it was hypothesized that external dynamic hydraulic stimulation (DHS) can generate ImP with minimal strain in a frequency-dependent manner. The aim of this study was to evaluate the immediate effects on local and distant ImP and bone strain induced by a novel, non-invasive dynamic external pressure stimulus in response to a range of loading frequencies.
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Schachter, Levanto G., Deborah K. Lieu, and Abdul I. Barakat. "Stent-Induced Arterial Flow Disturbance: Whole Vessel and Cellular Considerations." In ASME 2002 International Mechanical Engineering Congress and Exposition. ASMEDC, 2002. http://dx.doi.org/10.1115/imece2002-32584.
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Although the use of endovascular stents has significantly reduced the incidence of restenosis following balloon angioplasty, restenosis rates remain unacceptably high (20–35% of all angioplasty procedures [1]). Placement of a stent within an arterial segment locally injures vascular endothelium thereby stimulating thrombotic responses that contribute to the development of in-stent restenosis. Recent research suggests that the local fluid mechanical environment in the vicinity of a stent impacts the rate of vessel re-endothelialization following stent-induced injury [2]. This is supported by in vitro data demonstrating that endothelial repair after injury is sensitive to fluid mechanical forces [3]. Recent in vivo data suggest that in-stent restenosis preferentially develops in arterial regions exposed to low and/or oscillatory shear stress [1]. Therefore, it is essential to establish the detailed flow environment in the vicinity of a stent and to investigate the impact of this environment on EC function.
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Gomaa, A. M. M., D. V. S. V. S. Gupta, and P. Carman. "Proppant Transport? Viscosity Is Not All It's Cracked Up To Be." In SPE Hydraulic Fracturing Technology Conference. SPE, 2015. http://dx.doi.org/10.2118/spe-173323-ms.
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Abstract Post-treatment production analyses for hydraulic fracturing treatments with conventional crosslinked gel often indicate that the treatments do not achieve the designed stimulation effectiveness, which could be attributed to non-optimal proppant placement and/or significantly damaged fracture conductivity. Although conventional crosslinked fluids are observed to provide good proppant suspension in laboratory environments, they might not provide the desired proppant transport under downhole conditions. Crosslinked fluids are known to be difficult to clean up, and thus are notorious for imparting gel damage to proppant pack and formation. Surfactant gels have been developed to mitigate some of the issues. Viscosity measurements are used as the main tool to judge and optimize the performance of both polymer and surfactant based fracture fluids, especially their ability to transport proppant. While efficient proppant transport is essential for successful hydraulic fracturing, recent laboratory work has shown that viscosity alone may not accurately assess proppant transport. The objective of the paper is to investigate and determine the minimum rheological properties required for efficient proppant transport. Thus, combinations of rotational and oscillatory measurements were conducted to better predict the proppant transport characteristics. Also, proppant settling tests were conducted at static and dynamic conditions. A strong correlation was established between fluid's elasticity and its ability to suspend the proppant with a required minimum elastic modulus (G') value to be greater than viscous modulus (G”). Experimental results show that for two fluids that both have a close viscosity value (similar power law parameters); one fluid with G'>G” while the other one G'< G”, the fluid that has G'>G” behaves as semi-solid material where it deforms instead of flowing when shear stress is applied, while the fluid that has G”>G', flows when shear stress is applied and time to flow depends on viscosity. A proppant particle in a fluid undergoes shear stress due to its density. Therefore, for the fluid G”>G', proppant settles as the fluid moves around it and the speed of settling depends on fluid viscosity, whereas for the elastic fluid (G'>G”), fluid elasticity does not allow the proppant to settle. This observation was confirmed for both polymer and surfactant based fracturing fluids. Additives can be divided into categories that may enhance or reduce fluid elasticity based on their effect on the internal structure of the fluids. For example, breakers tend to significantly reduce the fluid elasticity, even when viscosity reduction is minimized. Data obtained from this study can be used as a guideline to optimize and select the fluid that has ability to carry proppant for field treatment design.
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Khokhar, Saad Yousuf, Mustansar Raza, Hossam Elmoneim, Arif Yousuf, Rameez Anwar, Saqib Jah Temuri, Salman Saeed Muhammad, Afnan Dar Ahmed, and Kamil Shehzad. "Is Fluidic Oscillator a Game Changer in Improving Well Productivity? An Analysis with Case Studies." In ADIPEC. SPE, 2022. http://dx.doi.org/10.2118/211144-ms.
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Abstract The case studies performed in the Middle East and South Asia region shared in the paper reflect the requirement of production/injection enhancement in challenging downhole conditions. Larger tubing diameter, limitations of minimum ID to deploy bigger OD tools, low bottom hole pressures, and requirement of high annular and jetting velocities are often demanded in CT clean-out operations. The advancements in coiled tubing metallurgies to intervene in complex wellbore geometries and the precision of downhole simulators to predict on-site scenarios have put more pressure on the efficiency of downhole tools in production enhancement services. Thus, the case studies required a tool that could overcome the barriers offered by incumbent technologies. It is confirmed from laboratory tests that a standoff of eight times the orifice diameter and fluid velocity of 200 ft/sec is required to remove moderate to hard deposits from wellbores. Conventional jetting tools have a standoff distance of more than 40 times and fluid velocities are far below 200 ft/sec thus objectives of CT intervention are often compromised. Moreover, the effectiveness of conventional tools for critical matrix in the stimulation operations is barely minimum as the jetting effect diverges from the jetting stream. A new type of fluidic oscillator was utilized in the case studies. Unlike pulsating effects created by 1st generation of the fluidic oscillators, the SFO type oscillator had triple jetting action namely, Helix jetting, Pulses Jetting, and Cavitation jetting which was equally effective for in-wellbore and near- wellbore regions. Paper also explains the working mechanism of the tool and demonstrates its ability to remove the skin in the critical matrix The results of the clean-out with SFO technology were beyond expectations. It reduced the operating times to two-thirds of conventional operations, which led to cost savings in all the case studies by an average of 35%. Moreover, it increased the efficiency of treatment fluids which resulted in the reduction of waste of additives, and the requirement of extra efforts to dispose of excess materials at wellsite. Also, jetting effectiveness caused an increase in production/injection from 30%- to 250% This is the first technology that uses cavitation jetting in oilfield services and the first to use aforesaid jetting actions altogether in one tool. The technology adopted in the case studies doesn't have moving or rotating parts, thus eliminating the requirement to pull CT out of the hole for redressing and can perform long operations in one go. It doesn't depend on the centralization of the tool as the jetting effect is passed via kinetic energy through submersed fluids, thus can target deeper depth without limitations of the standoff. It allows a higher flow rate of liquid and gas, thus offering higher energies for clean-out and stimulation operations.