Hydrostatic Pressure Measurements Research Articles

Tight junctions control lumen morphology via hydrostatic pressure and junctional tension.

Formation of fluid-filled lumina by epithelial tissues is essential for organ development. How cells control the hydraulic and cortical forces to control lumen morphology is not well understood. Here, we quantified the mechanical role of tight junctions in lumen formation using MDCK-II cysts. We found that the paracellular ion barrier formed by claudin receptors is not required for the hydraulic inflation of a lumen. However, the depletion of the zonula occludens scaffold resulted in lumen collapse and folding of apical membranes. Combining quantitative measurements of hydrostatic lumen pressure and junctional tension with modeling enabled us to explain lumen morphologies from the pressure-tension force balance. Tight junctions promote lumen inflation by decreasing cortical tension via the inhibition of myosin. In addition, our results suggest that excess apical area contributes to lumen opening. Overall, we provide a mechanical understanding of how epithelial cells use tight junctions to modulate tissue and lumen shape.

Automated assessment of hydrostatic pressure resistance in woven fabrics using the enhanced YOLOv8 network

Hydrostatic pressure resistance serves as a crucial metric in the assessment of water resistance in woven fabrics. The expeditious, precise, and efficient conduct of hydrostatic pressure tests holds paramount importance in advancing the progress and production of high-performance textiles. Addressing the challenges posed by intricate printed patterns on woven fabrics, and the presence of small, widely scattered water droplets, the study leverages the enhanced YOLOv8 model to develop a machine vision-based automated detection technique for assessing water resistance in woven fabric. The proposed method incorporates convolutional block attention module attention mechanisms into the backbone and neck network, replaces the path aggregation network structure of YOLOv8 with the bidirectional feature pyramid network structure, and introduces a dedicated detection head for small targets. These enhancements facilitate accurate identification of water outlet points on the woven fabric and precise recording of frame positions, enabling the precise measurement of hydrostatic pressure. Validation of the proposed model is conducted through a series of comparative experiments utilizing a self-collected dataset. The experimental results underscore the exemplary performance of the proposed model, evidenced by an AP0.5 score of 92.18%, showcasing superior overall efficacy in comparison with alternative models. Notably, the target localization time error is found to be less than 2 s when contrasted with manual detection. This method substantially enhances the accuracy of water droplet detection and localization in hydrostatic pressure resistance testing of woven fabric, characterized by complex surface patterns, thereby contributing to refinement of hydrostatic pressure testing methodologies in woven fabric analysis.

Pressure‐Induced Dual‐Emission of Mn‐Based Metal Halides (C5H6N)2MnBr4

AbstractRegulating the crystal structure of metal halides is important to tune their photoluminescence (PL) or govern the potential emergence of diverse physical properties. Here, an exceptional PL phenomenon characterized by dual‐emission bands in the Mn‐based metal halides (C5H6N)2MnBr4 is observed through hydrostatic pressure measurements. The results have confirmed that the dual‐emission bands centered at ≈518 and 650 nm arise from isolated Mn2+ ions and super‐exchange within Mn2+–Mn2+ dimers, respectively. (C5H6N)2MnBr4 displays remarkable piezochromic luminescence, accompanied by a red shift in dual‐emission. This phenomenon can be attributed to the enhancement of crystal‐field splitting energy and the reduction of relaxation from the low‐energy excited state 4T1 to the ground state 6A1. Meanwhile, the dual‐emission exhibits an anomalous increase ≈1.5–3.9 GPa, which is associated with reduced nonradiative losses during energy migration due to the decreased distance between the luminescent centers as a consequence of lattice contraction. Moreover, (C5H6N)2MnBr4 undergoes a phase transition at ≈1.5 GPa, and upon decompression, the high‐pressure phase partially recovers. This study not only provides insights into the luminescent properties of Mn‐based metal halides but also presents a novel approach to the design of multifunctional photoluminescent materials.

All-fiber MZI hydrostatic pressure sensor

With the rapid development of physical ocean observation, high-performance pressure sensor integrated with stable mechanical strength, sufficient pressure sensitivity as well as negligible temperature crosstalk is highly desirable but still lack of research. This paper proposes an all-fiber optical sensor based on a Mach-Zehnder interferometer (MZI) for hydrostatic pressure measurement, utilizing a multi-mode fiber (MMF)-single-hole-dual-core fiber (SHDCF)-MMF structure. The MMF sections act as a beam splitter and coupler to enhance the Mach-Zehnder interference. The SHDCF serves as the pressure-sensing section. Under the action of the enclosed air hole in SHDCF, hydraulic variations cause changes in the structural parameters of the fiber, especially the refractive index change caused by the elasto-optical effect, which leads to the shift of the interference dips. The experimental results prove that the SHDCF-based MZI sensor has a higher hydrostatic pressure sensitivity than other hole-less silica fiber-based sensors. The max pressure sensitivity is −0.2358 nm/MPa in the range of 0.1 MPa to 16.1 MPa with good linearity and reliability. Moreover, the low temperature–pressure cross-sensitivity of 0.04368 MPa/℃ also proves our sensor more competitive in harsh environment applications.

Spin density wave and antiferromagnetic transition in EuFe2As2: a high field transport and heat capacity study

Abstract Here we reported structural, electrical, magnetic, and thermal transport properties of ternary pnictide bulk iron based compound EuFe2As2 (Eu-122). This compound (Eu-122) crystallized in ThCr2Si2-type tetragonal phase structure with space group I4/mmm at ambient temperature. A promising divalent state (Eu2+) of Eu-ions was observed in the studied EuFe2As2. Magnetic ordering of Eu2+ ions takes place at very low temperature at around T N = 20 K in EuFe2As2. The ferromagnetic interactions between Fe–Fe ions were established at higher temperature which was revealed from magnetic susceptibility measurements with negative value of the paramagnetic Curie temperature. Both magnetic phase transitions (20 K and 190 K) were clearly established the intrinsic magnetic nature revealed by both electrical transport and specific heat measurement. However the phase transition at low temperature corresponds to the magnetic ordering of Eu2+ ions while the high transition temperature is due to the itinerant moment of Fe. EuFe2As2 is the only compound among various parent compounds of iron pnictide superconductor’s family, in which both spin density wave (SDW) of Fe and A-type antiferromagnetic (AFM) ordering of the localized Eu2+ magnetic moments take place simultaneously. We observed here that the localized character of Eu anti-ferromagnetism dominated via RKKY interactions, despite the largely itinerant nature of Fe magnetic interactions. The resistivity with applied magnetic field revealed that the AFM ordering temperature of Eu2+ ions suppress with applied magnetic field. Also resistivity under hydrostatic pressure measurements shows the T SDW (Fe) transition of the Fe moments shifts towards the lower temperatures while AFM ordering of Eu2+ decreases with pressure and the same is completely disappears at 2 GPa.

ENGINEERING AND GEOLOGICAL STUDIES OF THE TENGIZ DEPOSIT

In this article, a study of geological and ecological loads on the geological environment at the Tengizfield, located in the Zhyloy district of Atyrau region of the Republic of Kazakhtan, is carried out. Soil tests by dynamic sounding (STDS) were performed on all drilling wells for sandy soils. In the process of performing engineering and geological exploration, static sounding of soils was performed at the projected sites of GDP-1 (gas distribution plant) and Torch, with the measurement of hydrostatic pore pressure. Physical and mechanical properties of soils, chemical properties of soils and chemical properties of groundwater were determined during laboratory studies. In the studied territory, the soils composing the engineering-geological section to a depth of up to 25 m are saline with an average degree of salinity. All lithological-facies groups of soils also contain a significant amount of carbonates and gypsum in their composition. For loamy silt (IGE-1b), according to the combination of physico-chemical and mechanical characteristics (fluid consistency, high degree of salinity, high degree of compressibility and low strength, the possibility of manifestation of thixotropic properties under dynamic influences), this soil belongs to the category of weak water-saturated clay soils. Weak soil (IGE-1b) is observed at a shallow depth in some areas. The available geotechnical data is not enough to accommodate areas of weak soils. At the same time, heavy sandy loam (IGE1a) and light sandy clay (IGE-8) have swelling properties of a weak degree. Chemical analysis of groundwater samples taken within the studied territories showed a high degree of mineralization, groundwater belongs to the brackish group, a subgroup of strongly brackish waters. Dangerous geological processes that could negatively affect the construction conditions are characterized by the processes of secondary salinization of soils.

Numerical modelling of 1-dimensional silicon photonic crystal sensor for hydrostatic pressure measurement

Abstract In this work, a highly sensitive hydrostatic pressure sensor using one-dimensional (1D) photonic-crystal (PC) is designed and analyzed numerically for its sensing performance. The device design has silicon (Si) sensing layer at the top to sense the applied pressure. The proposed sensor performance has been studied for its pressure sensing, by applying boundary load on the sensing layer. The structure is designed, simulated and analyzed using an FEM tool. As the applied pressure is varied from 0 MPa to 10 MPa, resonant mode shifts towards the higher wavelength region. The effect of defect cavity length and the number of periods are also analyzed to choose the optimized value which enhances the sensor performance parameters. Simulation result shows that the proposed sensor has a very high sensitivity of 250 nm/GPa and Q-factor of 11,120 with the transmission of 99.99%.

Improved Sensitivity of Ultrasound-Based Subharmonic Aided Pressure Estimation Using Monodisperse Microbubbles.

Subharmonic aided pressure estimation (SHAPE) has been shown effective for noninvasively measuring hydrostatic fluid pressures in a variety of clinical applications. The objective of this study was to explore potential improvements in SHAPE sensitivity using monodisperse microbubbles. Populations of monodisperse microbubbles were created using a commercially available microfluidics device (Solstice Pharmaceuticals). Size distributions were assessed using a Coulter Counter and stability of the distribution following fabrication was evaluated over 24 hours. Attenuation of the microbubble populations from 1 to 10 MHz was then quantified using single element transducers to identify each formulation's resonance frequency. Frequency spectra over increasing driving amplitudes were investigated to determine the nonlinear phases of subharmonic signal generation. SHAPE sensitivity was evaluated in a hydrostatic pressure-controlled water bath using a Logiq E10 scanner (GE Healthcare). Monodisperse lipid microbubble suspensions ranging from 2.4 to 5.3 μm in diameter were successfully created and they showed no discernable change in size distribution over 24 hours following activation. Calculated resonance frequencies ranged from 2.1 to 6.3 MHz and showed excellent correlation with microbubble diameter (R2 > 0.99). When investigating microbubble frequency response, subharmonic signal occurrence was shown to begin at 150 kPa peak negative pressure, grow up to 225 kPa, and saturate at approximately 250 kPa. Using the Logiq E10, monodisperse bubbles demonstrated a SHAPE sensitivity of -0.17 dB/mmHg, which was nearly twice the sensitivity of the commercial polydisperse microbubble currently being used in clinical trials. Monodisperse microbubbles have the potential to greatly improve the sensitivity of SHAPE for the noninvasive measurement of hydrostatic pressures.

Revealing the competition between charge density wave and superconductivity in CsV3Sb5 through uniaxial strain

In this paper we report the impact of uniaxial strain $\varepsilon$ applied along the crystalline $a$ axis on the newly discovered kagome superconductor CsV$_3$Sb$_5$. At ambient conditions, CsV$_3$Sb$_5$ shows a charge-density wave (CDW) transition at $T_{\rm CDW}=94.5$ K and superconducts below $T_C = 3.34$ K. In our study, when the uniaxial strain $\varepsilon$ is varied from $-0.90\%$ to $0.90\%$, $T_C$ monotonically increases by $\sim 33\%$ from 3.0 K to 4.0 K, giving rise to the empirical relation $T_C (\varepsilon)=3.4+0.56\varepsilon+0.12\varepsilon^2$. On the other hand, for $\varepsilon$ changing from $-0.76\%$ to $1.26\%$, $T_{\rm CDW}$ decreases monotonically by $\sim 10\%$ from 97.5 K to 87.5 K with $T_{\rm CDW}(\varepsilon)=94.5-4.72\varepsilon-0.60\varepsilon^2$. The opposite response of $T_C$ and $T_{\rm CDW}$ to the uniaxial strain suggests strong competition between these two orders. Comparison with hydrostatic pressure measurements indicate that it is the change in the $c$-axis that is responsible for these behaviors of the CDW and superconducting transitions, and that the explicit breaking of the sixfold rotational symmetry by strain has a negligible effect. Combined with our first-principles calculations and phenomenological analysis, we conclude that the enhancement in $T_C$ with decreasing $c$ is caused primarily by the suppression of $T_{\rm CDW}$, rather than strain-induced modifications in the bare superconducting parameters. We propose that the sensitivity of $T_{\rm CDW}$ with respect to the changes in the $c$-axis arises from the impact of the latter on the trilinear coupling between the $M_1^+$ and $L_2^-$ phonon modes associated with the CDW. Overall, our work reveals that the $c$-axis lattice parameter, which can be controlled by both pressure and uniaxial strain, is a powerful tuning knob for the phase diagram of CsV$_3$Sb$_5$.

Hollow-glass-microsphere-assisted half-circle interference for hydrostatic pressure measurement with high sensitivity

We propose and demonstrate a half-circle interferometer using a hollow glass microsphere (HGM) resonator. The half-circle interference is induced by a mismatch between the fundamental mode in the HGM and the modes in the capillary wall. The theoretical model is verified by comparing the simulated and experimental results. The variation in capillary length induced by the axial pressure contributes the most to the half-circle interference, which features a device with a high hydrostatic pressure sensitivity of -1.099 nm/kPa. This device shows potential as a hydrostatic pressure sensor owing to its stability, high sensitivity, and robustness.

Electronic transport properties and hydrostatic pressure effect of FeSe0.67Te0.33 single crystals free of phase separation

FeSe1−x Te x superconductors manifest some intriguing electronic properties depending on the value of x. In FeSe single crystal, the nematic phase and Dirac band structure have been observed, while topological surface superconductivity (SC) with the Majorana bound state was found in the crystal of x∼ 0.55. Therefore, the electronic properties of single crystals with 0 < x ⩽ 0.5 are crucial for probing the evolution of those intriguing properties as well as their relations. However, this study is still left blank due to the lack of single crystals because of phase separation. Here, we report the synthesis, magnetization, electronic transport properties, and hydrostatic pressure effect of FeSe0.67Te0.33 single crystals free of phase separation. A structural (nematic) transition is visible at T s = 39 K, below which the resistivity exhibits a Fermi-liquid behavior. Analysis of the upper critical fields suggests that spin-paramagnetic effect should be taken into account for both H || c axis and H || ab plane. A crossover from the low-H quadratic to the high-H quasi-linear behavior is observed in the magnetoresistance, signifying the possible existence of Dirac-cone state. Besides, the strong temperature dependence of Hall coefficient, violation of (modified) Kohler’s rule, and two-band model analysis indicate the multiband effects in FeSe0.67Te0.33 single crystals. Hydrostatic pressure measurements reveal that T s is quickly suppressed with pressure while T c is monotonically increased up to 2.31 GPa, indicating the competition between nematicity and SC. No signature of magnetic order that has been detected in FeSe1−x S x is observed. Our findings fill up the blank of the knowledge on the basic properties of FeSe1−x Te x system with low-Te concentrations.

Application of the uniaxial pressure technique in studying superconductors

<p indent=0mm>Because of the rapid development of the uniaxial pressure device in recent years, the uniaxial pressure or strain technique has been increasingly applied to study unconventional superconductors. The physical properties of a sample will change with the uniaxial strain along a particular lattice axis, providing us with important information regarding superconductivity and other characteristics. When compared with hydrostatic pressure measurement, changes in physical properties with the uniaxial pressure are mainly associated with symmetry, making this methodology particularly suitable for studying the symmetry-related properties of a system such as the electronic nematic phase with rotational symmetry breaking. Furthermore, the uniaxial pressure technique can be used to study the superconducting properties. In this review, we will briefly introduce some typical uniaxial pressure and uniaxial strain devices and techniques and their applications on iron-based superconductors as well as other superconductors. The uniaxial pressure technique exhibits some unique advantages with respect to the study of electronic nematicity, superconductivity, and some other competing orders. With further development, the uniaxial pressure technique is expected to play increasingly important roles in the study of superconductors and other strongly correlated systems.

Dewatering microcrystalline cellulose: The influence of ionic strength

This study investigates the influence of the ionic strength on the dead-end filtration of microcrystalline cellulose (MCC) suspensions in the range of 0.1–1 g/L NaCl, in altering the electrostatic interactions between particles. The formation of larger agglomerates of increasing ionic concentration was observed using Focused Beam Reflectance Measurement (FBRM®). Local filtration properties were investigated as the experimental set-up allowed for measurements of local hydrostatic pressure and solidosity to be made. The results show that the addition of ions decreases both the average and local filtration resistance. The formation of a resistant skin layer was observed for the suspension without the addition of NaCl but was counteracted when ions were added. Furthermore, the ionic strength did not seem to have any notable effect on the structure of the cake in the range 0.15–1.0 g/L NaCl. However, the pressure dependency of the solidosity at lower ionic concentration was higher. The local filtration properties were fitted to semi-empirical relations, which indicated the formation of moderately to highly compressible cakes when NaCl was added.

Traceable calibration of pressure based water level data loggers

This paper investigates accuracy, influence of temperature variations and time drift of water level data loggers, operating on a principle of hydrostatic pressure measurement. The laboratory setup for calibration of such devices, equipped with self-designed pressure chamber and commercial climatic chamber is presented. Calibration procedure for logger’s built-in pressure transducer, with ensured traceability to the primary standards of pressure and temperature, is proposed. Influence of temperature on the pressure reading was examined by conducting calibration at 10 °C, 15 °C and 25 °C.

Quantifying Auger recombination coefficients in type-I mid-infrared InGaAsSb quantum well lasers

From a systematic study of the threshold current density as a function of temperature and hydrostatic pressure, in conjunction with theoretical analysis of the gain and threshold carrier density, we have determined the wavelength dependence of the Auger recombination coefficients in InGaAsSb/GaSb quantum well lasers emitting in the 1.7–3.2 µm wavelength range. From hydrostatic pressure measurements, the non-radiative component of threshold currents for individual lasers was determined continuously as a function of wavelength. The results are analysed to determine the Auger coefficients quantitatively. This procedure involves calculating the threshold carrier density based on device properties, optical losses, and estimated Auger contribution to the total threshold current density. We observe a minimum in the Auger rate around 2.1 µm. A strong increase with decreasing mid-infrared wavelength (<2 µm) indicates the prominent role of intervalence Auger transitions to the split-off hole band (CHSH process). Above 2 µm, the increase with wavelength is approximately exponential due to CHCC or CHLH Auger recombination, limiting long wavelength operation. The observed dependence is consistent with that derived by analysing literature values of lasing thresholds for type-I InGaAsSb quantum well diodes. Over the wavelength range considered, the Auger coefficient varies from a minimum of 1 × 10−16cm 4 s−1 at 2.1 µm to ∼8 × 10−16cm4 s−1 at 3.2 µm.

Nanoscale Measurements of Elastic Properties and Hydrostatic Pressure in H2‐Bulged MoS2 Membranes

AbstractThe combination of extremely high stiffness and bending flexibility with tunable electrical and optical properties makes van der Waals transition metal dichalcogenides appealing both for fundamental science and applied research. By taking advantage of localized H2‐bulged MoS2 membranes, an innovative approach, based on atomic force microscopy nanoindentation, is demostrated and discussed here, aiming at measuring elastic and thermodynamic properties of nanoblisters made of 2D materials. The results, interpreted in the membrane limit of the Föppl–von Karman equation, lead to the quantification of the internal pressure and mole number of the trapped H2 gas, as well as of the stretching modulus and adhesion energy of the MoS2 membrane. The latter is discussed in the limit of strong (clamped and fully bonded interlayer interface) shear, as experimentally achieved in the investigated H2‐bulged 2D blisters. Moreover, this approach allows to quantify the stress, and consequently the strain, locally imposed to the MoS2 membrane by the bulging of the domes.

Laboratory Evaluation of Static and Dynamic Sag in Oil-Based Drilling Fluids

SummaryIn this paper, we present the results of barite sag measurements before and after hot-rolled oil-based drilling fluids (OBDFs) using different approaches for characterization. We characterized the barite sag of a liquid column under static condition using light-scattering (LS) measurements, hydrostatic pressure measurements, and gamma densitometry. Under the dynamic condition, we used a rheometer with a grooved bob-in-cup measuring system to characterize barite sag in rotational and oscillatory shear conditions. Extensive rheological characterization of the drilling fluid samples, before hot rolling (BHR) and after hot rolling (AHR), is carried out. It is found that barite sag decreased in hot-rolled fluid samples from the LS, rotational, and oscillatory shear measurements. The rheological characterization of the fluid samples showed that heat-activated chemicals in the hot-rolled fluid sample increased the viscosity and elasticity, which contributed to lower barite sag and longer suspension of particles than BHR. Both hydrostatic and gamma densitometry measurements reveal more or less uniform compaction of barite particles in the fluid sample below the liquid layer. Time-dependent oscillatory shear measurements provide new insights on the structural character of drilling fluids to predict barite sag tendencies during the fluid design phase.

CURRENT STATE OF METHODS AND MEANS OF REGISTRATION OF HIGH TEMPERATURES AND MECHANICAL STRESSES IN STRUCTURES

An analytical review of physically possible methods and available achievements in registering hydrostatic pressure or mechanical stresses using fiber optic fibers and sensors based on them based on published works that can be used in harsh environmental conditions is carried out. The results of the review show that fully distributed or quasidistributed fiber-optic systems for recording hydrostatic pressure or mechanical stress can be implemented on the following physical principles and apparatus with measures to compensate or suppress the influence of temperature: polarizing sensors on birefringent single- mode light guides and OTDR equipment; micro-flexible sensors with OTDR equipment on conventional multimode fibers; measuring systems on fiber Bragg gratings; on discrete sensors, in particular, on sealed fiber Fabry–Perot interferometers; Brillouin distributed sensors on single-mode fibers that are not sensitive to temperature changes. It is shown that single-mode birefringent fibers with hollow holes in the shell and fiber Bragg gratings written in the core have a good linear sensitivity to hydrostatic pressure and a weak dependence on temperature. Lattices in phosphorous-containing single-mode light guides have increased high-temperature properties up to ~500 C and higher. A number of discrete fiber sensors’ structures and pressure recorders are investigated. Various structures of sensitive elements of pressure sensors on sealed fiber Fabry–Perot interferometers and fiber gratings in spherical and cylindrical small-sized cases are investigated. Sensors based on Fabry–Perot fiber interferometers soldered into a glass capillary and protected from water by external high-temperature hermetic coatings showed good linearity in the pressure range of 0…540 ATM at temperatures up to ~200 C. The sensors are efficient at temperatures up to 600 °C and are promising for use in severe and special external conditions. The possibility of compensating the temperature sensitivity by selecting external coatings is shown. Pressure sensors were tested on local areas with microbends and it was shown that they can measure pressures up to ~24 МPа at temperatures up to ~450 C, but to compensate for the dependence of the readings on temperature, it must be measured by an independent sensor. The possibility of independent and simultaneous measurement of hydrostatic pressure and temperature along a single fiber using spontaneous Brillouin scattering is shown. Pressure is measured by the frequency shift of Brillouin scattering, and temperature by its intensity. The operation of the Brillouin recorder in the pressure range 0…34 MРа is demonstrated. The pressure resolution was ~0,2 МРа. New methods are proposed for detecting Brillouin scattering – a heterodyne signal with a high signal-to-noise ratio and based on frequency modulation of a semiconductor single-frequency distributed feedback laser. The measurement range has been increased by more than 10 km and the coordinate resolution has been increased. The Brillouin scattering method is promising for creating distributed systems for measuring hydrostatic pressure or mechanical stress for severe physical conditions, including temperatures of ≥3000 C.

Determination of optimum slurry evaluation method for the prediction of BaTiO3 green sheet density

ABSTRACTIn this study, the particle dispersion state in a dense BaTiO3 slurry containing a dispersant and binder was assessed by various slurry evaluations such as particle size distribution measurement by laser diffraction, viscosity measurement, dynamic viscoelasticity measurement, and hydrostatic pressure measurement, which is a novel slurry evaluation technique developed by our group. Then, the relationship between the slurry evaluation results and the packing fraction of green sheets fabricated from these slurries was discussed. We found that the particle size distribution and the relative viscosity and yield stress by dynamic viscoelasticity measurement could not properly estimate the packing fraction of green sheets. In contrast, the hydrostatic pressure measurement was able to distinguish the particle dispersion state, and the results show an acceptable correlation with the packing fraction. The reason is that our developed method evaluates not only the initial particle dispersion state, but also its change as the particle concentration increases.

Long-Term Outcome of Mini-Open Surgical Decompression for Chronic Exertional Compartment Syndrome of the Forearm in Professional Motorcycling Riders.

To evaluate results of mini-open fasciotomy (MOF) in high-level motorcycling or motocross riders with chronic exertional compartment syndrome (CECS) at long-term follow-up (minimum 5 years). Case series. IV. University Hospital/Private Practice. Fifty-four professional motorcycling riders treated with MOF for a CECS of the forearm from January 2006 to June 2011. Inclusion criteria comprised: high-level motorcycling or motocross riders, clinical symptoms of CECS for at least 6 months, diagnosis confirmed using preoperative compartment hydrostatic pressure measurement and/or magnetic resonance imaging of the forearm, minimum follow-up of 5 years. A MOF to obtain decompression of all compartments was performed in all patients. Visual analog scale; a subjective scale to measure strength; QuickDash functional scores. Time to resume full riding capacities as short-term evaluation. A total of 54 patients who underwent 77 MOF procedures overall (23 bilateral) were included. The mean age was 23.6 ± 5.2 years. Mean Visual Analog Scale decreased from a preoperative value of 68.2 to a 3-month postoperative value of 26 (P < 0.001). Mean QuickDash scale was 84 at preoperative registration, falling to 20, 3 months after surgery (P < 0.001) and down to 12 at 1-year follow-up (P = 0.017). The average time to return to full riding capacities was 3.5 ± 1 week. Mini-open fasciotomy resulted safe and effective for the treatment of chronic exertional compartment syndrome in high-level motorcycling or motocross riders. The good outcome at follow-up resulted stable at 5 years and the incidence of complications remained low. Our data demonstrate that the resolution of symptoms is reliable and durable. Pain recovery was immediate after surgery, instead functional scores showed a more gradual recovery throughout the 12 months after surgery. Mini-open fasciotomy is a reliable treatment for CECS of the forearm in professional motorcycling riders. This treatment should also be considered in young riders due to the absence of tardive relapse reported in this study.