Articles de revues : « Microgravity monitoring »

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Yu, Peidong, Stefan Frank-Richter, Alexander Börngen et Matthias Sperl. « Monitoring three-dimensional packings in microgravity ». Granular Matter 16, n^o 2 (21 janvier 2014) : 165–73. http://dx.doi.org/10.1007/s10035-013-0479-8.

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Williams-Jones, Glyn, Hazel Rymer, Guillaume Mauri, Joachim Gottsmann, Michael Poland et Daniele Carbone. « Toward continuous 4D microgravity monitoring of volcanoes ». GEOPHYSICS 73, n^o 6 (novembre 2008) : WA19—WA28. http://dx.doi.org/10.1190/1.2981185.

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Four-dimensional or time-lapse microgravity monitoring has been used effectively on volcanoes for decades to characterize the changes in subsurface volcanic systems. With measurements typically lasting from a few days to weeks and then repeated a year later, the spatial resolution of theses studies is often at the expense of temporal resolution and vice versa. Continuous gravity studies with one to two instruments operating for a short period of time (weeks to months) have shown enticing evidence of very rapid changes in the volcanic plumbing system (minutes to hours) and in one case precursory signals leading to eruptive activity were detected. The need for true multi-instrument networks is clear if we are to have both the temporal and spatial reso-lution needed for effective volcano monitoring. However, the high cost of these instruments is currently limiting the implementation of continuous microgravity networks. An interim approach to consider is the development of a collaborative network of researchers able to bring multiple instruments together at key volcanoes to investigate multitemporal physical changes in a few type volcanoes. However, to truly move forward, it is imperative that new low-cost instruments are developed to increase the number of instruments available at a single site. Only in this way can both the temporal and spatial integrity of monitoring be maintained. Integration of these instruments into a multiparameter network of continuously recording sensors is essential for effective volcano monitoring and hazard mitigation.

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Du, Chunhui, Changhe Yin, Hong Cheng, Feiyu Yuan et Yang Zhao. « Microgravity Monitoring in Fractured-Vuggy Carbonate Reservoirs ». Geofluids 2023 (14 janvier 2023) : 1–7. http://dx.doi.org/10.1155/2023/5034948.

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With the development of Tahe Oilfield entering the high water cut stage, gas channeling occurs in fractured-vuggy system during nitrogen injection, resulting in some inefficient wells. To improve the development effect of gas flooding, how to define the distribution of fracture, vuggy, and remaining oil has become one of the urgent problems to be solved at present. Microgravity monitoring technology uses high-quality data, the residual gravity anomaly of the target layer is obtained by depth recursion processing, the density distribution of the target layer is obtained by layer density inversion, and the fractured-vuggy distribution is depicted by edge detection. The results show that the lower part of the fractured-vuggy system in the north is connected to the middle, while the fractured-vuggy system in the south is directly connected to the middle, which leads to different effects of injected nitrogen. The early injected nitrogen in the SX area is mainly distributed in the north. Nitrogen injection in the north needs to reach a certain amount of gas before the middle can be effective. Nitrogen is injected in the south, and the central part is effective quickly. The research results provide a basis for adjusting injection-production scheme and improving reservoir development effect. Compared with the production performance and seismic interpretation results, it verifies the accuracy of ultradeep microgravity monitoring in depicting the development of fractured-vuggy system, which provides a new technology and idea for characterizing fractured-vuggy carbonate reservoirs.

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Avan, Paul, Hervé Normand, Fabrice Giraudet, Grégory Gerenton et Pierre Denise. « Noninvasive in-ear monitoring of intracranial pressure during microgravity in parabolic flights ». Journal of Applied Physiology 125, n^o 2 (1 août 2018) : 353–61. http://dx.doi.org/10.1152/japplphysiol.00032.2018.

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Among possible causes of visual impairment or headache experienced by astronauts in microgravity or postflight and that hamper their performance, elevated intracranial pressure (ICP) has been invoked but never measured for lack of noninvasive methods. The goal of this work was to test two noninvasive methods of ICP monitoring using in-ear detectors of ICP-dependent auditory responses, acoustic and electric, in acute microgravity afforded by parabolic flights. The devices detecting these responses were handheld tablets routinely used in otolaryngology for hearing diagnosis, which were customized for ICP extraction and serviceable by unskilled operators. These methods had been previously validated against invasive ICP measurements in neurosurgery patients. The two methods concurred in their estimation of ICP changes with microgravity, i.e., 11.0 ± 7.7 mmHg for the acoustic method ( n = 7 subjects with valid results out of 30, auditory responses being masked by excessive in-flight noise in 23 subjects) and 11.3 ± 10.6 mmHg for the electric method ( n = 10 subjects with valid results out of 10 tested despite the in-flight noise). These results agree with recent publications using invasive access to cerebrospinal fluid in parabolic flights and suggest that acute microgravity has a moderate average effect on ICP, similar to body tilt from upright to supine, yet with some subjects undergoing large effects whereas others seem immune. The electric in-ear method would be suitable for ICP monitoring in circumstances and with subjects such that invasive measurements are excluded. NEW & NOTEWORTHY In-ear detectors of intracranial pressure-dependent auditory responses allow intracranial pressure to be monitored noninvasively during acute microgravity. The average pressure increase during 20-s long sessions in microgravity is 11 mmHg, comparable with an effect of body tilt. However, intersubject variability is large, with subjects who repeatedly experience from nothing to twice the average effect. A systematic in-flight use would allow the relationship between space adaptation syndrome and ICP to be established or dismissed.

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BROWN, G. C., H. RYMER et D. STEVENSON. « Volcano monitoring by microgravity and energy budget analysis ». Journal of the Geological Society 148, n^o 3 (mai 1991) : 585–93. http://dx.doi.org/10.1144/gsjgs.148.3.0585.

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Smith, Thomas G., Federico Formenti, Peter D. Hodkinson, Muska Khpal, Brian P. Mackenwells et Nick P. Talbot. « Monitoring Tissue Oxygen Saturation in Microgravity on Parabolic Flights ». Gravitational and Space Research 4, n^o 2 (18 juillet 2020) : 2–7. http://dx.doi.org/10.2478/gsr-2016-0007.

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AbstractFuture spacecraft and crew habitats are anticipated to use a moderately hypobaric and hypoxic cabin atmosphere to reduce the risk of decompression sickness associated with extravehicular activity. This has raised concerns about potential hypoxia-mediated adverse effects on astronauts. Noninvasive technology for measuring tissue oxygen saturation (StO2) has been developed for clinical use and may be helpful in monitoring oxygenation during spaceflight. We conducted a technical evaluation of a handheld StO2 monitor during a series of parabolic flights, and then undertook a preliminary analysis of the data obtained during the flights from six individuals. The StO2 monitor operated normally in all gravity conditions. There was considerable variability in StO2 between and within individuals. Overall, transition to microgravity was associated with a small decrease in StO2 of 1.1±0.3%. This evaluation has established the basic function of this technology in microgravity and demonstrates the potential for exploring its use in space.

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Tahvanainen, K., E. Länsimies, P. Tikkanen, J. Hartikainen, T. Kärki, T. Lyyra et M. Mäntysaari. « Microcomputer-based monitoring of cardiovascular functions in simulated microgravity ». Advances in Space Research 12, n^o 1 (janvier 1992) : 227–36. http://dx.doi.org/10.1016/0273-1177(92)90287-8.

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Pringle, Jamie K., Peter Styles, Claire P. Howell, Michael W. Branston, Rebecca Furner et Sam M. Toon. « Long-term time-lapse microgravity and geotechnical monitoring of relict salt mines, Marston, Cheshire, U. K. » GEOPHYSICS 77, n^o 6 (1 novembre 2012) : B287—B294. http://dx.doi.org/10.1190/geo2011-0491.1.

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The area around the town of Northwich in Cheshire, U. K., has a long history of catastrophic ground subsidence caused by a combination of natural dissolution and collapsing abandoned mine workings within the underlying Triassic halite bedrock geology. In the village of Marston, the Trent and Mersey Canal crosses several abandoned salt mine workings and previously subsiding areas, the canal being breached by a catastrophic subsidence event in 1953. This canal section is the focus of a long-term monitoring study by conventional geotechnical topographic and microgravity surveys. Results of 20 years of topographic time-lapse surveys indicate specific areas of local subsidence that could not be predicted by available site and mine abandonment plan and shaft data. Subsidence has subsequently necessitated four phases of temporary canal bank remediation. Ten years of microgravity time-lapse data have recorded major deepening negative anomalies in specific sections that correlate with topographic data. Gravity 2D modeling using available site data found upwardly propagating voids, and associated collapse material produced a good match with observed microgravity data. Intrusive investigations have confirmed a void at the major anomaly. The advantages of undertaking such long-term studies for near-surface geophysicists, geotechnical engineers, and researchers working in other application areas are discussed.

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Cazzaniga, Alessandra, Fabian Ille, Simon Wuest, Carsten Haack, Adrian Koller, Christina Giger-Lange, Monica Zocchi, Marcel Egli, Sara Castiglioni et Jeanette A. Maier. « Scalable Microgravity Simulator Used for Long-Term Musculoskeletal Cells and Tissue Engineering ». International Journal of Molecular Sciences 21, n^o 23 (24 novembre 2020) : 8908. http://dx.doi.org/10.3390/ijms21238908.

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We introduce a new benchtop microgravity simulator (MGS) that is scalable and easy to use. Its working principle is similar to that of random positioning machines (RPM), commonly used in research laboratories and regarded as one of the gold standards for simulating microgravity. The improvement of the MGS concerns mainly the algorithms controlling the movements of the samples and the design that, for the first time, guarantees equal treatment of all the culture flasks undergoing simulated microgravity. Qualification and validation tests of the new device were conducted with human bone marrow stem cells (bMSC) and mouse skeletal muscle myoblasts (C2C12). bMSC were cultured for 4 days on the MGS and the RPM in parallel. In the presence of osteogenic medium, an overexpression of osteogenic markers was detected in the samples from both devices. Similarly, C2C12 cells were maintained for 4 days on the MGS and the rotating wall vessel (RWV) device, another widely used microgravity simulator. Significant downregulation of myogenesis markers was observed in gravitationally unloaded cells. Therefore, similar results can be obtained regardless of the used simulated microgravity devices, namely MGS, RPM, or RWV. The newly developed MGS device thus offers easy and reliable long-term cell culture possibilities under simulated microgravity conditions. Currently, upgrades are in progress to allow real-time monitoring of the culture media and liquids exchange while running. This is of particular interest for long-term cultivation, needed for tissue engineering applications. Tissue grown under real or simulated microgravity has specific features, such as growth in three-dimensions (3D). Growth in weightlessness conditions fosters mechanical, structural, and chemical interactions between cells and the extracellular matrix in any direction.

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Lindley, E. J., B. H. Brown, D. C. Barber, D. Grundy, R. Knowles, F. J. McArdle et A. J. Wilson. « Monitoring body fluid distribution in microgravity using impedance tomography (APT) ». Clinical Physics and Physiological Measurement 13, A (1 décembre 1992) : 181–84. http://dx.doi.org/10.1088/0143-0815/13/a/035.

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Pratiwi, Dian, et Agung Wiyono. « PEMANTAUAN PROSES INJEKSI AIR PADA LAPANGAN “SMR” CEKUNGAN SUMATERA TENGAH BERDASARKAN DATA ANOMALI TIME-LAPSE MICROGRAVITY ». Jurnal Geofisika Eksplorasi 4, n^o 1 (17 janvier 2020) : 112–25. http://dx.doi.org/10.23960/jge.v4i1.10.

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There had been done a regional research about monitoring of injection process in "SMR" field of Central Sumatera Basin using microgravity method. The time-lapse microgravity method is the development of the gravity method (x, y, z) by adding the fourth dimension of time (t). Monitoring is carried out on production fields that have performed EOR (Enchanced Oil Recovery) ie the process of injecting water into the reservoir to push and drain the remnants of oil in the pores of the reservoir rock to the production well. The microgravity data processing is done by finding the difference between observed gravity values between the first and the second measurements, then performing the spectral analysis to separate the anomaly at reservoir depth and noise. The time-lapse microgravity anomaly has a value of -132.28 μGal to 54.89 μGal. Positive anomalies are related to the injection process, whereas the negative anomalies are related to the production process in the study area. Filtering analysis shows that there are two zones of fluid dynamics, which is due to the process of surface water dynamics (groundwater above reservoir) and that occurs in the reservoir. Fluid reduction zones occur in areas with more production wells than injection wells. Density reduction occurs in the reservoir layer at a depth of 600 m to 1000 m with a maximum reduction value of -3.1x10-3 gr / cm3. The gravity time-lapse inversion model shows the existence of several injection wells that are less effective and therefore need to be stopped injecting.

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Maiolino, Jaqueline Vaz, Célio Costa Vaz et Marcelo Lopes de Oliveira e Souza. « In-Flight Qualification of the Suborbital Microgravity Platform in Brazil ». International Journal of Advanced Engineering Research and Science 9, n^o 12 (2022) : 527–33. http://dx.doi.org/10.22161/ijaers.912.58.

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The Suborbital Microgravity Platform (PSM) is the first Brazilian suborbital payload developed to be launched using the Suborbital Vehicles VSB-30, with two stages, or VS-30, with one stage, both also fully Brazilian. This platform was designed to allow performing scientific and/or technological experiments, lasting 6 to 8 minutes in a microgravity environment, through suborbital ballistic flight and experiments recovering at sea. In addition to serving as a platform for holding experiments to meet the government demands of the Brazilian Space Agency (AEB) Microgravity Program, the PSM also has enormous potential to meet national and international private demands for carrying out scientific, technological, and commercial experiments in microgravity environment. Regarding its in-flight qualification, the PSM was launched by the Suborbital Booster Vehicle VSB-30, on October 23, 2022, from the Alcântara Launch Center (CLA) in Brazil. This article presents a summary of the PSM in-flight qualification, which includes: its description, the main stages of its development and a descriptive summary of the telemetry monitoring, whose data were received and decoded in real time by the PSM Launch Control Unit (BC-PSM). The successful qualification and flight performance of the PSM, in conformance with project requirements, demonstrated the compliance of mission flight events, and thus, enable Brazil technologically to carry out microgravity experiments in a suborbital space environment with a recoverable platform.

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Davis, Kristofer, Yaoguo Li et Michael Batzle. « Time-lapse gravity monitoring : A systematic 4D approach with application to aquifer storage and recovery ». GEOPHYSICS 73, n^o 6 (novembre 2008) : WA61—WA69. http://dx.doi.org/10.1190/1.2987376.

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We studied time-lapse gravity surveys applied to the monitoring of an artificial aquifer storage and recovery (ASR) system in Leyden, Colorado. An abandoned underground coal mine has been developed into a subsurface water reservoir. Water from surface sources is injected into the artificial aquifer during winter for retrieval and use in summer. As a key component in the geophysical monitoring of the artificial ASR system, three microgravity surveys were conducted over the course of ten months during the initial water-injection stage. The time-lapse microgravity surveys successfully detected the distribution of injected water as well as its general movement. Quantitative interpretation based on 3D inversions produced hydrologically meaningful density-contrast models and imaged major zones of water distribution. The site formed an ideal natural laboratory for investigating various aspects of time-lapse gravity methodology. Through this application, we have studied systematically all steps of the method, including survey design, data acquisition, processing, and quantitative interpretation.

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Griffith, Jacob L., Kim Cluff, Grant M. Downes, Brandon Eckerman, Subash Bhandari, Benjamin E. Loflin, Ryan Becker, Fayez Alruwaili et Noor Mohammed. « Wearable Sensing System for NonInvasive Monitoring of Intracranial BioFluid Shifts in Aerospace Applications ». Sensors 23, n^o 2 (14 janvier 2023) : 985. http://dx.doi.org/10.3390/s23020985.

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The alteration of the hydrostatic pressure gradient in the human body has been associated with changes in human physiology, including abnormal blood flow, syncope, and visual impairment. The focus of this study was to evaluate changes in the resonant frequency of a wearable electromagnetic resonant skin patch sensor during simulated physiological changes observed in aerospace applications. Simulated microgravity was induced in eight healthy human participants (n = 8), and the implementation of lower body negative pressure (LBNP) countermeasures was induced in four healthy human participants (n = 4). The average shift in resonant frequency was −13.76 ± 6.49 MHz for simulated microgravity with a shift in intracranial pressure (ICP) of 9.53 ± 1.32 mmHg, and a shift of 8.80 ± 5.2097 MHz for LBNP with a shift in ICP of approximately −5.83 ± 2.76 mmHg. The constructed regression model to explain the variance in shifts in ICP using the shifts in resonant frequency (R2 = 0.97) resulted in a root mean square error of 1.24. This work demonstrates a strong correlation between sensor signal response and shifts in ICP. Furthermore, this study establishes a foundation for future work integrating wearable sensors with alert systems and countermeasure recommendations for pilots and astronauts.

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Park, Yeong-Sue, Hyoungrae Rim, Mutaek Lim et Sung Bon Koo. « Cavity mapping and grout monitoring : a microgravity case history in Korea ». ASEG Extended Abstracts 2007, n^o 1 (1 décembre 2007) : 1. http://dx.doi.org/10.1071/aseg2007ab201.

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Barbu, A., M. Ellis, C. Kurwitz et F. Best. « Acoustic gauge monitoring of fluid inventory in a microgravity vortex separator ». Measurement Science and Technology 17, n^o 2 (19 janvier 2006) : 403–10. http://dx.doi.org/10.1088/0957-0233/17/2/023.

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Schneider, Stefan, Aleko Peipsi, Maria Stokes, Axel Knicker et Vera Abeln. « Feasibility of monitoring muscle health in microgravity environments using Myoton technology ». Medical & ; Biological Engineering & ; Computing 53, n^o 1 (21 octobre 2014) : 57–66. http://dx.doi.org/10.1007/s11517-014-1211-5.

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Sakharkar, Anurag, et Jian Yang. « Designing a Novel Monitoring Approach for the Effects of Space Travel on Astronauts’ Health ». Life 13, n^o 2 (18 février 2023) : 576. http://dx.doi.org/10.3390/life13020576.

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Space exploration and extraterrestrial civilization have fascinated humankind since the earliest days of human history. It was only in the last century that humankind finally began taking significant steps towards these goals by sending astronauts into space, landing on the moon, and building the International Space Station. However, space voyage is very challenging and dangerous, and astronauts are under constant space radiation and microgravity. It has been shown that astronauts are at a high risk of developing a broad range of diseases/disorders. Thus, it is critical to develop a rapid and effective assay to monitor astronauts’ health in space. In this study, gene expression and correlation patterns were analyzed for 10 astronauts (8 male and 2 female) using the publicly available microarray dataset E-GEOD-74708. We identified 218 differentially expressed genes between In-flight and Pre-flight and noticed that space travel decreased genome regulation and gene correlations across the entire genome, as well as individual signaling pathways. Furthermore, we systematically developed a shortlist of 32 genes that could be used to monitor astronauts’ health during space travel. Further studies, including microgravity experiments, are warranted to optimize and validate the proposed assay.

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Lv, Qijun, Aiping Zheng, Xiangjin Liang, Hongfei Chen, Shichang Ju, Yanchong Meng, Hongyuan Zhang, Guolin He, Shenshen Deng et Junfang Li. « Research on Remaining Oil Characterization in Superheavy Oil Reservoir by Microgravity Exploration ». Geofluids 2022 (18 juillet 2022) : 1–10. http://dx.doi.org/10.1155/2022/1210780.

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Some physical processes such as oil and gas development, metal deposit collection, and groundwater resource migration can cause density changes, for which microgravity monitoring is the most intuitive method to monitor the density change process. Based on the basic principle of microgravity measurement and the idea of multiscale separation, a multiscale, second-order, surface-fitting, residual gravity anomaly extraction method is proposed to separate superimposed microgravity fields. In this method, regional fields of different scales are fitted and calculated successively with the measurement points as the center, so as to separate the gravity anomalies produced by different-depth density bodies. Results from actual data show that this method extracts the reservoir’s residual density characteristics of plane gravity anomaly on the basis of remaining oil distribution characteristics, consistent with reservoir numerical simulation results. A three-dimensional least-squares inversion of the method for extracting residual gravity anomaly was carried out, with the inversion results consistent with the results of vertical remaining oil distribution characteristics and well-test production results.

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Crandall, C. G., M. Shibasaki, T. E. Wilson, J. Cui et B. D. Levine. « Prolonged head-down tilt exposure reduces maximal cutaneous vasodilator and sweating capacity in humans ». Journal of Applied Physiology 94, n^o 6 (1 juin 2003) : 2330–36. http://dx.doi.org/10.1152/japplphysiol.00790.2002.

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Cutaneous vasodilation and sweat rate are reduced during a thermal challenge after simulated and actual microgravity exposure. The effects of microgravity exposure on cutaneous vasodilator capacity and on sweat gland function are unknown. The purpose of this study was to test the hypothesis that simulated microgravity exposure, using the 6° head-down tilt (HDT) bed rest model, reduces maximal forearm cutaneous vascular conductance (FVC) and sweat gland function and that exercise during HDT preserves these responses. To test these hypotheses, 20 subjects were exposed to 14 days of strict HDT bed rest. Twelve of those subjects exercised (supine cycle ergometry) at 75% of pre-bed rest heart rate maximum for 90 min/day throughout HDT bed rest. Before and after HDT bed rest, maximal FVC was measured, via plethysmography, by heating the entire forearm to 42°C for 45 min. Sweat gland function was assessed by administering 1 × 10−6 to 2 M acetylcholine (9 doses) via intradermal microdialysis while simultaneously monitoring sweat rate over the microdialysis membranes. In the nonexercise group, maximal FVC and maximal stimulated sweat rate were significantly reduced after HDT bed rest. In contrast, these responses were unchanged in the exercise group. These data suggest that 14 days of simulated microgravity exposure, using the HDT bed rest model, reduces cutaneous vasodilator and sweating capacity, whereas aerobic exercise training during HDT bed rest preserves these responses.

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Ferguson, J. F., T. Chen, J. Brady, C. L. Aiken et J. Seibert. « The 4D microgravity method for waterflood surveillance : Part II — Gravity measurements for the Prudhoe Bay reservoir, Alaska ». GEOPHYSICS 72, n^o 2 (mars 2007) : I33—I43. http://dx.doi.org/10.1190/1.2435473.

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Between 1994 and 2002, a series of experiments was conducted at Prudhoe Bay, Alaska, aimed at the development of an effective 4D (or time-lapse) gravity technique. Theoretical investigations had pointed out the potential for monitoring water injection in the [Formula: see text]-deep reservoir, but it was not clear that gravity measurements of sufficient accuracy could be made in the arctic environment. During the course of these experiments, new techniques and instrumentation were introduced and perfected for both gravity and position measurements. Gravity stations are located using high-precision global positioning system (GPS) techniques without permanent monuments. Robust methods for meter drift control have improved noise resistance in relative gravimeter surveys. Absolute gravity measurements with a field-portable instrument maintain absolute gravity levels among surveys. A 4D gravity-difference noise of [Formula: see text] standard deviation has been established at Prudhoe Bay for GPS-controlled relative gravimeter surveys. The lessons learned are now being applied to full-scale waterflood monitoring at Prudhoe Bay. The basic technique is applicable to microgravity surveys and 4D microgravity surveys for any purpose.

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Minardi, Suhayat, Teguh Ardianto et Alfina Taurida Alaydrus. « Surface Deformation Monitoring Using Time-lapse Microgravity Method in Central and East Lombok Regencies ». Indonesian Journal of Physics 31, n^o 2 (19 août 2020) : 16–23. http://dx.doi.org/10.5614/itb.ijp.2020.31.2.3.

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Surface deformation is a natural occurrence on the surface of the earth. The deformation can be in the form of subsidence or uplifting of the land surface. In this research, an time-lapse microgravity method will be applied to monitor surface deformation that occurs in Central Lombok and East Lombok Districts. The method of time-lapse microgravity is repetitive gravity measurement at the same point with a certain time interval, the measured magnitude is a change in the value of the acceleration of gravity and the microGal scale. Measurements were made in August 2016, April 2018, and June 2019. The measured value of the change in gravitational acceleration is the superposition of the changes caused by subsurface and surface sources. Separation of the two values is carried out using striping filter, which takes into account the ratio of density, thickness, and depth of the surface and subsurface layers. Land subsidence occurred during the period August 2016 to April 2018 and land uplifting occurred during the April 2018 to June 2019 period. This land subsidence occurred due to natural compacting and minor tectonic activity (small earthquakes that were not felt) while land uplifting was occurred due to major tectonic activities, in the form of the Lombok Earthquake in July to September 2018.

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Kühn, Jonas. « Digital holographic microscopy real-time monitoring of cytoarchitectural alterations during simulated microgravity ». Journal of Biomedical Optics 15, n^o 2 (1 mars 2010) : 026021. http://dx.doi.org/10.1117/1.3377960.

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Seibert, John E., et Jerry L. Brady. « Potential ionospheric impacts on the Prudhoe Bay Alaska microgravity Waterflood Monitoring Survey ». GPS Solutions 6, n^o 4 (mars 2003) : 271–72. http://dx.doi.org/10.1007/s10291-002-0039-x.

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Neelam, Srujana, Audrey Lee, Michael A. Lane, Ceasar Udave, Howard G. Levine et Ye Zhang. « Module to Support Real-Time Microscopic Imaging of Living Organisms on Ground-Based Microgravity Analogs ». Applied Sciences 11, n^o 7 (1 avril 2021) : 3122. http://dx.doi.org/10.3390/app11073122.

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Since opportunities for spaceflight experiments are scarce, ground-based microgravity simulation devices (MSDs) offer accessible and economical alternatives for gravitational biology studies. Among the MSDs, the random positioning machine (RPM) provides simulated microgravity conditions on the ground by randomizing rotating biological samples in two axes to distribute the Earth’s gravity vector in all directions over time. Real-time microscopy and image acquisition during microgravity simulation are of particular interest to enable the study of how basic cell functions, such as division, migration, and proliferation, progress under altered gravity conditions. However, these capabilities have been difficult to implement due to the constantly moving frames of the RPM as well as mechanical noise. Therefore, we developed an image acquisition module that can be mounted on an RPM to capture live images over time while the specimen is in the simulated microgravity (SMG) environment. This module integrates a digital microscope with a magnification range of 20× to 700×, a high-speed data transmission adaptor for the wireless streaming of time-lapse images, and a backlight illuminator to view the sample under brightfield and darkfield modes. With this module, we successfully demonstrated the real-time imaging of human cells cultured on an RPM in brightfield, lasting up to 80 h, and also visualized them in green fluorescent channel. This module was successful in monitoring cell morphology and in quantifying the rate of cell division, cell migration, and wound healing in SMG. It can be easily modified to study the response of other biological specimens to SMG.

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Porzucek, Slawomir, Monika Loj et Kajetan d’Obyrn. « Surface Microgravity Monitoring of Underground Water Migration : A Case Study in Wieliczka, Poland ». Energies 15, n^o 11 (30 mai 2022) : 4012. http://dx.doi.org/10.3390/en15114012.

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Excessive water inflow in a mine poses a great threat to its operation, especially in the case of a salt mine. In 1992, a rapid outflow of water occurred in the Mina traverse in the Wieliczka Salt Mine, and a number of investigations were undertaken to assess the causes of the outflow and the condition of the rock mass, including the gravity and microgravity surveys discussed in this paper. The first of these was to investigate the rock mass with respect to its geological, hydrogeological properties and mining. The aim of study was to monitor the changes in the rock mass density and the impact of these changes on the subsidence of the ground surface. The surveys provided information on the geological structure of the study area and helped to identify possible routes for water migration. The first data confirmed density changes in the shallow parts of the rock mass, manifested by subsidence of the land surface. However, the subsequent measurements failed to show any significant density changes in the shallow parts of the rock mass, despite the subsidence of the land surface. Therefore, it can be argued that the processes in the rock mass did not cause voids in the shallow parts of the rock mass that could lead to discontinuous deformations. These processes run deep and caused only continuous deformations in the form of subsidence basins.

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Salloum-Abou-Jaoude, Georges, Henri Nguyen-Thi, Guillaume Reinhart, Ragnvald H. Mathiesen, Gerhard Zimmermann et Daniela Voss. « Characterization of Motion of Dendrite Fragment by X-Ray Radiography on Earth and under Microgravity Environment ». Materials Science Forum 790-791 (mai 2014) : 311–16. http://dx.doi.org/10.4028/www.scientific.net/msf.790-791.311.

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In the frame of ESA-MAP (Microgravity Application Promotion) project entitled XRMON (In situ X-Ray MONitoring of advanced metallurgical processes under microgravity and terrestrial conditions), a microgravity (μg) experiment in the XRMON-GF (Gradient Furnace) setup was successfully launched in 2012 on board MASER 12 sounding rocket. During this experiment, in situ and real time observations of the formation of the solidification microstructures in diffusive conditions were carried out for the first time by using X-ray radiography. In addition, two reference experiments with the same control parameters but in ground-based conditions were performed to enable us a direct comparison with the μg experiment and therefore to enlighten the effects of gravity upon microstructure formation. This communication reports on fragmentation phenomenon observed during those experiments. For 1g upward solidification, fragmentations mainly take place in the upper part of the mushy zone. After their detachments, dendrite fragments are carried away by buoyancy force in the bulk liquid where they are gradually remelted. For μg experiment and horizontal solidification, this type of fragmentation is not observed. However, a great number of fragmentations are surprisingly revealed by in situ observation in the deep part of the mushy zone, when the liquid fraction is very small. Moreover, as soon as they are detached, the dendrite fragments move toward the cold part of the mushy zone, even in the case of μg experiment. The observations suggest that sample shrinkage may be at the origin of this fragment motion.

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Rybakov, M., V. Goldshmidt, L. Fleischer et Y. Rotstein. « Cave detection and 4-D monitoring : A microgravity case history near the Dead Sea ». Leading Edge 20, n^o 8 (août 2001) : 896–900. http://dx.doi.org/10.1190/1.1487303.

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Dinatolo, Michael F., et Luchino Y. Cohen. « Monitoring the Impact of Spaceflight on the Human Brain ». Life 12, n^o 7 (15 juillet 2022) : 1060. http://dx.doi.org/10.3390/life12071060.

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Extended exposure to radiation, microgravity, and isolation during space exploration has significant physiological, structural, and psychosocial effects on astronauts, and particularly their central nervous system. To date, the use of brain monitoring techniques adopted on Earth in pre/post-spaceflight experimental protocols has proven to be valuable for investigating the effects of space travel on the brain. However, future (longer) deep space travel would require some brain function monitoring equipment to be also available for evaluating and monitoring brain health during spaceflight. Here, we describe the impact of spaceflight on the brain, the basic principles behind six brain function analysis technologies, their current use associated with spaceflight, and their potential for utilization during deep space exploration. We suggest that, while the use of magnetic resonance imaging (MRI), positron emission tomography (PET), and computerized tomography (CT) is limited to analog and pre/post-spaceflight studies on Earth, electroencephalography (EEG), functional near-infrared spectroscopy (fNIRS), and ultrasound are good candidates to be adapted for utilization in the context of deep space exploration.

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Hamilton, Douglas R., Ashot E. Sargsyan, Kathleen Garcia, Douglas J. Ebert, Peggy A. Whitson, Alan H. Feiveson, Irina V. Alferova et al. « Cardiac and vascular responses to thigh cuffs and respiratory maneuvers on crewmembers of the International Space Station ». Journal of Applied Physiology 112, n^o 3 (1 février 2012) : 454–62. http://dx.doi.org/10.1152/japplphysiol.00557.2011.

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Background: the transition to microgravity eliminates the hydrostatic gradients in the vascular system. The resulting fluid redistribution commonly manifests as facial edema, engorgement of the external neck veins, nasal congestion, and headache. This experiment examined the responses to modified Valsalva and Mueller maneuvers measured by cardiac and vascular ultrasound (ECHO) in a baseline steady state and under the influence of thigh occlusion cuffs available as a countermeasure device (Braslet cuffs). Methods: nine International Space Station crewmember subjects (expeditions 16–20) were examined in 15 experiment sessions 101 ± 46 days after launch (mean ± SD; 33–185). Twenty-seven cardiac and vascular parameters were obtained with/without respiratory maneuvers before and after tightening of the Braslet cuffs (162 parameter states/session). Quality of cardiac and vascular ultrasound examinations was assured through remote monitoring and guidance by investigators from the NASA Telescience Center in Houston, TX, and the Mission Control Center in Korolyov, Moscow region, Russia. Results: 14 of 81 conditions (27 parameters measured at baseline, Valsalva, and Mueller maneuver) were significantly different when the Braslet was applied. Seven of 27 parameters were found to respond differently to respiratory maneuvers depending on the presence or absence of thigh compression. Conclusions: acute application of Braslet occlusion cuffs causes lower extremity fluid sequestration and exerts commensurate measurable effects on cardiac performance in microgravity. Ultrasound techniques to measure the hemodynamic effects of thigh cuffs in combination with respiratory maneuvers may serve as an effective tool in determining the volume status of a cardiac or hemodynamically compromised patient at the “microgravity bedside.”

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Nursalam, La Ode, A. Arisona, R. Ramli, La Harudu, Sitti Kasmiati, Eko Harianto, Fahrudi Ahwan Ikhsan et Andri Estining Sejati. « Mapping of Subsurface Geological Structure and Land Cover Using Microgravity Techniques for Geography and Geophysic Surveys : A Case Study of Maluri Park, Malaysia ». Geosfera Indonesia 4, n^o 3 (25 novembre 2019) : 280. http://dx.doi.org/10.19184/geosi.v4i3.13738.

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A microgravity investigation on bedrock topography was conducted at Maluri park reference level in Kuala Lumpur, Malaysia. The study aim to mapping the near-surface structure and soil and land cover distribution for geography and geophysics surveys. Two types of cross-section modeling of the residual anomaly generated the MaluriBouguer Anomaly model for site-1 and site-2 at Maluri Park. The 2D microgravity models produced the contour map, displaying the characterization due to density contrast in rock types while mapping the subsurface geological structure at different depths. Moreover, a synthetic model was initiated with the assumption of lateral distance on the left and right sides taken at 50 m and a depth of 60 m. The results of modeling confirmed that the soil and rock type composition on both models site tests are topsoil (1.1 to 1.92 g/cm3), soil (1.8 g/cm3), clay (1.63 g/cm3), gravel (1.7 g/cm3), sand (2.0 g/cm3), shale (2.4 g/cm3), sandstone (2.76 g/cm3), and limestone (2.9 g/cm3). The 2D gravity modeling using two model site tests obtained a correspondence with the observed microgravity data. Keywords: Bouguer anomaly, limestone, microgravity, soil structure, topography. References Amaluddin, L. O., Rahmat, R., Surdin, S., Ramadhan, M. I., Hidayat, D. N., Purwana, I. G., & Fayanto, S. (2019). The Effectiveness of Outdoor Learning in Improving Spatial Intelligence. Journal for the Education of Gifted Young Scientists, 7(3), 667–680. https://doi.org/10.17478/jegys.613987 Arisona,A., Mohd N., Amin E.K., &Abdullahi, A.(2018).Assessment of microgravity anomalies of soil structure for geotechnical 2d models.Journal of Geoscience, Engineering, Environment, and Technology (JGEET)3(3), 151-154. Georgsson, L.S. (2009). Geophysical Methotds Used in Geothermal Exploration. Presented at Exploration for Geothermal Resources, 1-22 November 2009, 1-16. Grandjean, G. (2009). From Geophysical Parameters to Soil Characteristics.Florida: Report N°BRGM/FP7-DIGISOIL Project Deliverable 2.1, Final ReportDepartment of Civil and Coastal EngineeringUniversity of Florida. Hiltunen, D.R., Hudyma,N.,Tran,K.T.,&Sarno,A.I. (2012).Geophysical Testing of Rock and Its Relationthipsto Physical Properties.Florida:Final ReportDepartment ofCivil and Coastal EngineeringUniversity ofFlorida. Kirsch,R. (2006).GroundwaterGeophysics, ATool for Hydrogeology.New York: Springer. Kamal,H.,Taha,M.,&Al-Sanad,S. (2010). Geoenvironmental Engineering and Geotechnics, GeoShanghai 2010 International Conference. (accessed 02.03.17) Lilie, R.J. (1999).Whole Earth Geophysics: An Introductory Textbook for Geologists and Geophysicists. New Jersey:Prentice-HallInc. Pringle, J.K., Styles, P., Howell, C.P.,Branston, M.W., Furner, R., &Toon,S.M. (2012). Long-term time-lapse microgravity and geotechnical monitoring of relict salt mines, marston, cheshire, uk. Geophysic77(6), 165-171. Samsudin, H.T.(2003).A microgravity survey over deep limestone bedrock.Bulletin of Geological Society of Malaysia4(6), 201-208. Tan, S.M. (2005). Karsticfeatures of kualalumpur limestone. Bulletin of the Institution of EnginnerMalaysia 4(7), 6-11. Tajuddin, A.&Lat, C.N. (2004).Detecting subsurfacevoids using the microgravity method, a case study from kualalipis, pahang.Bulletin of Geological Society of Malaysia 3(48), 31-35. Tuckwell, G., Grossey, T., Owen, S., & Stearns, P. (2008). The use of microgravity to detect small distributed voids and low-density ground. Quarterly Journal of Engineering Geology and Hydrogeology, 41(3), 371–380. https://doi.org/10.1144/1470-9236/07-224 Wanjohi, A.W. (2014). Geophysical Field Mapping. Presented at Exploration for Geothermal Resources, 2-23 November 2014, 1-9. Yusoff , Z.M., Raju,G. &Nahazanan, H.(2016).Static and dynamic behaviour of kualalumpur limestone. Malaysian Journal of Civil Engineering Special Issue Vol.28 (1), p.:18-25. Zabidi, H. & De Freitas, M.H. (2011).Re-evaluation of rock core logging for the prediction of preferred orientations of karst in the kualalumpur limestone formation. Engineering Geology, 117(3-4), p.: 159–169. Copyright (c) 2019 Geosfera Indonesia Journal and Department of Geography Education, University of Jember This work is licensed under a Creative Commons Attribution-Share A like 4.0 International License

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Lin, P. P., et K. Jules. « An intelligent system for monitoring the microgravity environment quality on-board the international space station ». IEEE Transactions on Instrumentation and Measurement 51, n^o 5 (octobre 2002) : 1002–9. http://dx.doi.org/10.1109/tim.2002.806016.

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Rahmani, Dinda, et Darharta Dahrin. « Pemodelan Penyebaran Massa CO2 Terinjeksi dalam reservoir untuk Mendapatkan Respon Anomali Time-lapse microgravity di Permukaan ». Jurnal Geofisika 15, n^o 2 (20 novembre 2019) : 36. http://dx.doi.org/10.36435/jgf.v15i2.408.

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Dalam proyek CCS, monitoring bawah permukaan perlu dilakukan dengan baik agar CO2 yang diinjeksikan dapat tersimpandengan aman di dalam reservoir. Salah satu metode geofisika yang dapat digunakan untuk monitoring bawah permukaan adalah metode gravity. Dengan membuat model sintetik volume reservoir, tekanan dan temperatur bawah permukaan, serta perhitungan aliran fluida pada rentang waktu tertentu, dapat diprediksi radius penyebaran CO2 dan distribusi densitasnya di dalam reservoir. Radius penyebaran dan kontras densitas yang didapatkan, digunakan untuk pemodelan ke depan time-lapse microgravity dengan menggunakan software MATLAB versi R2012a yang telah divalidasi dengan software yang sudah ada sebelumnya, GRAV3D versi 2.0. Berdasarkan perhitungan dan pemodelan yang telah dilakukan, diketahui peningkatan tekanan bottomhole mengakibatkan perubahan sifat fisis CO2 yang mempengaruhi radius penyebarannya. Kemudian, respon anomali time-lapse microgravity yang dihasilkan menunjukkan kecenderungan nilai anomali yang terus meningkat seiring bertambahnya massa CO2 yang diinjeksikan. Nilai anomali setengah maksimum dan radius yang didapatkan pada hari ke 720, yaitu 1,323 x 10-1µGal dan 631,688 m untuk penyebaran massa CO2 di dalam reservoir sejauh 96,436 m. Dari kurva perbandingan tekanan reservoir terhadap tekanan fracture dan litostatik pada hari ke 720, didapatkan nilai tekanan pada kedalaman reservoir yang diinjeksikan CO2 masih jauh di bawah tekanan fracture dan litostatik, sehingga penambahan massa dari injeksi CO2 yang dimodelkan ini sangat kecil berpotensi untuk menimbulkan rekahan baru pada formasi. Dengan demikian, hasil pemodelan penyebaran CO2 dan distribusi densitasnya dalam reservoir, yang dikaitkan pula dengan perbandingan tekanan reservoir terhadap tekanan fracture dan litostatik, dapat digunakan untuk menentukan aman atau tidaknya injeksi CO2 yang dimodelkan.

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Jentzsch, Gerhard, Raymondo S. Punongbayan, Ulrich Schreiber, Günter Seeber, Christoph Völksen et Adelheid Weise. « Mayon volcano, Philippines : change of monitoring strategy after microgravity and GPS measurements from 1992 to 1996 ». Journal of Volcanology and Geothermal Research 109, n^o 1-3 (août 2001) : 219–34. http://dx.doi.org/10.1016/s0377-0273(00)00313-9.

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Branston, M. W., et P. Styles. « The application of Time-Lapse Microgravity for the Investigation and Monitoring of Subsidence at Northwich, Cheshire ». Quarterly Journal of Engineering Geology and Hydrogeology 36, n^o 3 (août 2003) : 231–44. http://dx.doi.org/10.1144/1470-9236/03-243.

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Wang, Junsheng, Jie Meng, Gege Ding, Yuejun Kang et Wenshuang Zhao. « A novel microfluidic capture and monitoring method for assessing physiological damage of C. elegans under microgravity ». ELECTROPHORESIS 40, n^o 6 (7 janvier 2019) : 922–29. http://dx.doi.org/10.1002/elps.201800461.

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Mata, Carlos. « Technology Focus : Production Monitoring (March 2021) ». Journal of Petroleum Technology 73, n^o 03 (1 mars 2021) : 48. http://dx.doi.org/10.2118/0321-0048-jpt.

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Last year, events accelerated several trends in the energy landscape. Oil and gas prices have remained low, and the industry is focusing more strongly on reducing costs and increasing operational efficiency. Reducing costs is not only about cutting costs today but also about reducing the life-cycle cost per barrel. Implementing innovative technologies that increase recovery requires a small investment but can bring large rewards. Advances in sensor accuracy, computing power, and data analytics unlock innovative use cases for technology for mapping subsurface movements of fluids. Very different technologies provide independent insights into the displacement process in the reservoir—for example, distributed acoustic sensing (DAS) used for periodic 4D seismic, time-lapse borehole microgravity surveys for 4D reservoir fluid mapping, DNA analytics to map interwell connectivity and zonal contributions, and interpreting downhole gauge pressure fluctuations caused by tidal forces to map fluid fronts. The aggregation of these uncorrelated insights helps geologists and reservoir engineers narrow down the number of possible realizations of the reservoir model, better map bypassed resources, and provide forecasts that are more realistic. On the production side, well instrumentation continues to become more affordable over time. For example: distributed temperature sensing, DAS, and downhole gauge lines can be run in a single optoelectric cable, which reduces well complexity and instrumentation costs. Wells can be instrumented at surface for less than $5,000 using wireless technologies. Wireless downhole gauges also can be retrofitted in older completions. There are many ways to leverage technology for improving production and reservoir monitoring and unlocking potential. The OnePetro online library offers a large collection of novel use cases for technology and algorithms applied to production and reservoir monitoring. The challenge now is to transform the way we work to realize the maximum value from such technology.

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Becker, David, Robert Schmidt, Gerhard Lindner et Klaus Stefan Drese. « Ultrasound Measurement Technique for Validation of Cryogenic Flows ». Proceedings 2, n^o 13 (11 décembre 2018) : 1090. http://dx.doi.org/10.3390/proceedings2131090.

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An ultrasound sensor system based on the transmission-mode approach is developed to enable the monitoring and sensing of cryogenic liquids and gases—especially gaseous bubbles and gas-liquid interfaces in liquid nitrogen (LN2). Common sensors do not meet requirements of cryogenic and microgravity-environments. Therefore, a special encapsulation design for the optimization of the electrical connection and the mechanical coupling of the ultrasound sensors is needed. The ultrasound system is qualified in LN2 and is able to measure bubbles (size and location) and fill levels with a high spatial resolution in a submillimetre range and a sampling rate of more than 500 Hz.

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Sathyan, Sandeep, Chang-Soo Kim, H. Troy Nagle, Christopher S. Brown et D. Marshall Porterfield. « A Flexible Microsensor Array for Root Zone Monitoring of a Porous Tube Plant Growth System for Microgravity ». Habitation 11, n^o 1 (1 décembre 2006) : 5–14. http://dx.doi.org/10.3727/154296606779507105.

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Reidt, Ulrich, Andreas Helwig, Gerhard Müller, Joachim Lenic, Jan Grosser, Viktor Fetter, Andrei Kornienko, Sergey Kharin, Natalia Novikova et Thomas Hummel. « Detection of Microorganisms with an Electronic Nose for Application under Microgravity Conditions ». Gravitational and Space Research 8, n^o 1 (17 juin 2020) : 1–17. http://dx.doi.org/10.2478/gsr-2020-0001.

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AbstractIn this work, we report on the construction, training and functional assessment of an electronic nose (called ‘E-Nose’) that is capable of monitoring the microbial contamination onboard space ships under microgravity conditions. To this end, a commercial electronic nose was modified to allow for the sampling of microbial volatile organic compounds (MVOCs) emitted from relevant bacterial and fungi species. Training of the modified ‘E-Nose’ was performed by establishing an MVOC database consisting of two Gram-positive bacteria strains (Bacillus subtilis and Staphylococcus warneri) and two fungi strains (Aspergillus versicolor and Penicillium expansum). All these strains are known to exist onboard the International Space Station (ISS) and to form important parts of its microbial contamination. All cultures were grown on four kinds of structural materials also in use onboard the ISS. The MVOCs emitted during the different growth phases of these cultures were monitored with an array of ten different metal oxide gas sensors inside the ‘E-Nose’. Principal component analysis of the array data revealed that B. subtilis and S. warneri form separate clusters in an optimized score plot, while the two fungi strains of A. versicolor and P. expansum form a large common cluster, well discriminated against to the bacteria clusters.

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Zahorec, Pavol, Peter Vajda, Juraj Papčo, Sergio Sainz-Maza Aparicio et Jorge Pereda De Pablo. « Prediction of vertical gradient of gravity and its significance for volcano monitoring – example from Teide volcano ». Contributions to Geophysics and Geodesy 46, n^o 3 (1 septembre 2016) : 203–20. http://dx.doi.org/10.1515/congeo-2016-0013.

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Abstract We present a detailed calculation of the topographic contribution to the vertical gradient of gravity (VGG) based on high-resolution digital elevation model (DEM) and new developed software (Toposk) for the purpose of predicting the actual VGGs in the field. The calculations presented here were performed for the Central Volcanic Complex (CVC) of Tenerife. We aimed at identifying the most extreme VGGs within the CVC, as well as predicting the VGGs at benchmarks of the former microgravity/deformation network set up to monitor the 2004/5 unrest. We have carried out an observational campaign in June 2016 to verify the predicted VGG values, both the extreme ones and those at the benchmarks. The comparison between the predicted and the in-situ verified VGGs is presented here. We demonstrate the sensitivity of the VGG prediction to the choice of the topo-rock density, which is inherent to the volcanic areas with high variability of rock densities. We illustrate the significance of the use of actual VGG in volcano monitoring microgravimetric surveys on a couple of benchmarks of the CVC network.

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Félix, Hugo, et Edson Santos Oliveira. « Non-Invasive Intracranial Pressure Monitoring and Its Applicability in Spaceflight ». Aerospace Medicine and Human Performance 93, n^o 6 (1 juin 2022) : 517–31. http://dx.doi.org/10.3357/amhp.5922.2022.

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INTRODUCTION: Neuro-ophthalmic findings collectively defined as Spaceflight-Associated Neuro-ocular Syndrome (SANS) are one of the leading health priorities in astronauts engaging in long duration spaceflight or prolonged microgravity exposure. Though multifactorial in etiology, similarities to terrestrial idiopathic intracranial hypertension (IIH) suggest these changes may result from an increase or impairing in intracranial pressure (ICP). Finding a portable, accessible, and reliable method of monitoring ICP is, therefore, crucial in long duration spaceflight. A review of recent literature was conducted on the biomedical literature search engine PubMed using the search term “non-invasive intracranial pressure”. Studies investigating accuracy of noninvasive and portable methods were assessed. The search retrieved different methods that were subsequently grouped by approach and technique. The majority of publications included the use of ultrasound-based methods with variable accuracies. One of which, noninvasive ICP estimation by optical nerve sheath diameter measurement (nICP_ONSD), presented the highest statistical correlation and prediction values to invasive ICP, with area under the curve (AUC) ranging from 0.75 to 0.964. One study even considers a combination of ONSD with transcranial Doppler (TCD) for an even higher performance. Other methods, such as near-infrared spectroscopy (NIRS), show positive and promising results [good statistical correlation with invasive techniques when measuring cerebral perfusion pressure (CPP): r = 0.83]. However, for its accessibility, portability, and accuracy, ONSD seems to present itself as the up to date, most reliable, noninvasive ICP surrogate and a valuable spaceflight asset.Félix H, Santos Oliveira E. Non-invasive intracranial pressure monitoring and its applicability in spaceflight. Aerosp Med Hum Perform. 2022; 93(6):517–531.

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Sugihara, Mituhiko, et Tsuneo Ishido. « Geothermal reservoir monitoring with a combination of absolute and relative gravimetry ». GEOPHYSICS 73, n^o 6 (novembre 2008) : WA37—WA47. http://dx.doi.org/10.1190/1.2991105.

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Microgravity monitoring is a valuable tool for mapping the redistribution of subsurface mass and for assessing changes in fluid recharge from reservoir boundaries associated with geothermal exploitation. To further the development of a high-precision absolute/relative hybrid gravity-measurement technique, we conducted measurements using an absolute gravimeter in two geothermal fields in Japan. The absolute gravity measurements were performed in the central production areas to directly measure gravity changes caused by fluid withdrawal. We succeeded in measuring long-term trends within an accuracy of a few microgals in the Okuaizu and Ogiri fields, which have been producing electricity for several years. Absolute measurements in the center of the field provide reliable and local reference datum anchor points for more widely distributed relative gravity measurements. In the Ogiri field, we carried out time-lapse hybrid measurements with this combination of absolute and relative gravimetry and delineated the spatial distributions of long- and short-term changes. The long-term changes are relatively small, considering the four-year observation interval. This suggests a near balance between the mass withdrawal rate from wells and mass recharge from peripheral regions. The apparent balance is reproduced fairly well by a preliminary numerical reservoir simulation study. The observed long- and short-term changes are thought to be useful constraints for planned history-matching studies based on refined reservoir models with greater spatial resolution that incorporate detailed well-by-well production histories.

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PAMUKÇU, OYA, TOLGA GÖNENÇ, AYÇA ÇIRMIK, PETEK SINDIRGI, İLKNUR KAFTAN et ÖZER AKDEMIR. « Investigation of vertical mass changes in the south of Izmir (Turkey) by monitoring microgravity and GPS/GNSS methods ». Journal of Earth System Science 124, n^o 1 (février 2015) : 137–48. http://dx.doi.org/10.1007/s12040-014-0533-x.

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Trudel, Guy, Nibras Shahin, Timothy Ramsay, Odette Laneuville et Hakim Louati. « Hemolysis contributes to anemia during long-duration space flight ». Nature Medicine 28, n^o 1 (janvier 2022) : 59–62. http://dx.doi.org/10.1038/s41591-021-01637-7.

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AbstractAnemia in astronauts has been noted since the first space missions, but the mechanisms contributing to anemia in space flight have remained unclear. Here, we show that space flight is associated with persistently increased levels of products of hemoglobin degradation, carbon monoxide in alveolar air and iron in serum, in 14 astronauts throughout their 6-month missions onboard the International Space Station. One year after landing, erythrocytic effects persisted, including increased levels of hemolysis, reticulocytosis and hemoglobin. These findings suggest that the destruction of red blood cells, termed hemolysis, is a primary effect of microgravity in space flight and support the hypothesis that the anemia associated with space flight is a hemolytic condition that should be considered in the screening and monitoring of both astronauts and space tourists.

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Waisberg, Ethan, Joshua Ong, Phani Paladugu, Sharif Amit Kamran, Nasif Zaman, Andrew G. Lee et Alireza Tavakkoli. « Challenges of Artificial Intelligence in Space Medicine ». Space : Science & ; Technology 2022 (29 octobre 2022) : 1–7. http://dx.doi.org/10.34133/2022/9852872.

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The human body undergoes many changes during long-duration spaceflight including musculoskeletal, visual, and behavioral changes. Several of these microgravity-induced effects serve as potential barriers to future exploration missions. The advent of artificial intelligence (AI) in medicine has progressed rapidly and has many promising applications for maintaining and monitoring astronaut health during spaceflight. However, the austere environment and unique nature of spaceflight present with challenges in successfully training and deploying successful systems for upholding astronaut health and mission performance. In this article, the dynamic barriers facing AI development in space medicine are explored. These diverse challenges range from limited astronaut data for algorithm training to ethical/legal considerations in deploying automated diagnostic systems in the setting of the medically limited space environment. How to address these challenges is then discussed and future directions for this emerging field of research.

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Fiedler, Patrique, Jens Haueisen, Ana M. Cebolla Alvarez, Guy Cheron, Pablo Cuesta, Fernando Maestú et Michael Funke. « Noise characteristics in spaceflight multichannel EEG ». PLOS ONE 18, n^o 2 (17 février 2023) : e0280822. http://dx.doi.org/10.1371/journal.pone.0280822.

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The cognitive performance of the crew has a major impact on mission safety and success in space flight. Monitoring of cognitive performance during long-duration space flight therefore is of paramount importance and can be performed using compact state-of-the-art mobile EEG. However, signal quality of EEG may be compromised due to the vicinity to various electronic devices and constant movements. We compare noise characteristics between in-flight extraterrestrial microgravity and ground-level terrestrial electroencephalography (EEG) recordings. EEG data recordings from either aboard International Space Station (ISS) or on earth’s surface, utilizing three EEG amplifiers and two electrode types, were compared. In-flight recordings showed noise level of an order of magnitude lower when compared to pre- and post-flight ground-level recordings with the same EEG system. Noise levels between ground-level recordings with actively shielded cables, and in-flight recordings without shielded cables, were similar. Furthermore, noise level characteristics of shielded ground-level EEG recordings, using wet and dry electrodes, and in-flight EEG recordings were similar. Actively shielded mobile dry EEG systems will support neuroscientific research and neurocognitive monitoring during spaceflight, especially during long-duration space missions.

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Bramanti, P., A. Malara, V. Salpietro, A. Calisto, F. Certo et C. A. Mariani. « 5-51-03 Cerebral blood flow changes in simulated microgravity condition studied by transcranial doppler monitoring in healthy volunteers ». Journal of the Neurological Sciences 150 (septembre 1997) : S338. http://dx.doi.org/10.1016/s0022-510x(97)86561-6.

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Simons, D. M., E. M. Gardner et P. I. Lelkes. « Dynamic culture in a rotating-wall vessel bioreactor differentially inhibits murine T-lymphocyte activation by mitogenic stimuli upon return to static conditions in a time-dependent manner ». Journal of Applied Physiology 100, n^o 4 (avril 2006) : 1287–92. http://dx.doi.org/10.1152/japplphysiol.00887.2005.

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Depressed immune function is a well-documented effect of spaceflight. Both in-flight studies and ground-based studies using microgravity analogs, such as rotating wall vessel (RWV) bioreactors, have demonstrated that mitogen-stimulated T lymphocytes exhibit decreased proliferation, IL-2 secretion, and activation marker expression in true microgravity and the dynamic RWV-culture environment. This study investigates the kinetics of RWV-induced T lymphocyte inhibition by monitoring the ability of Balb/c mouse splenocytes to become activated under static culture conditions after concanavalin A (Con A) stimulation in an RWV. Splenocytes were stimulated with Con A and cultured for up to 24 h in the RWV before being allowed to “recover” under static culture conditions in the continued presence of Con A. The T-lymphocyte fraction of splenocytes was assayed during the recovery period for IL-2 secretion, expansion of the T-lymphocyte population, and expression of the activation marker CD25. Our results indicate that CD25 expression was not affected by any duration of RWV exposure. In contrast, proliferation and IL-2 secretion were inhibited by >8 and 12 h of exposure, respectively. Culture in the RWV for 24 h resulted in a near-complete loss of cellular viability during the recovery period, which was not seen in cells maintained in the RWV for 16 h or less. Taken together, these results indicate that for up to 8 h of RWV culture activation is not significantly impaired upon return to static conditions; longer duration RWV culture results in a gradual loss of activation during the recovery period most likely because of decreased T-cell viability and/or IL-2 production.

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Shirakawa, Masaki, Fumiaki Tanigaki et Takashi Yamazaki. « Microbial Observatory Research in the International Space Station and Japanese Experiment Module “Kibo” ». Journal of Disaster Research 10, n^o 6 (1 décembre 2015) : 1025–30. http://dx.doi.org/10.20965/jdr.2015.p1025.

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The International Space Station (ISS) is a completely closed environment that offers a long-term microgravity environment. It is a unique environment where microbes can fly and attach themselves to devices or humans, especially the exposed parts of the body and head. The ongoing monitoring and analysis of microbes and their movement inside the Japanese Experiment Module (named “Kibo”) of the ISS are intended to study the effects of microbes on humans and prevent health hazards caused by microbes during a long-term space mission. This paper describes the current status and future plan of Japanese microbiological experiments to monitor microbial dynamics in Kibo. It also describes the future prospective and prioritized microbiological research areas based on the “Kibo utilization scenario towards 2020 in the field of life science.” Given the microbial research in space being actively conducted by the USA, NASA and international activities are also reported.

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