Lining Fluid Research Articles

Suspected anaphylaxis after intravenous administration of cefuroxime (Zinacef) in two dogs, with descriptions of arterial blood gas abnormalities over time

Two cases of suspected anaphylaxis occurred in the authors’ hospital within two weeks of each other. The first, a six-year-and-four-month-old border collie, presented for thoracic wall resection. Once anaesthetised, 20...

Dynamic modeling, simulation and experimental investigation on cryogenic tank pressurization system

ABSTRACT Propellant tank pressurization system in a cryogenic rocket engine is critical for successful mission performance. The current paper focused on dynamic analysis of the pressurization system with pneumatic pressure regulators as the significant dynamic elements. To evaluate the system dynamic behavior, a nonlinear model has been developed based on the fundamental equations by considering the compressible flow in the fluid lines and various forces inside the regulator such as pressure force, spring force, bellow force and Coulomb friction force. The simulation is carried out for nominal operating conditions of the pressure regulators and the pressurization system using AMESim simulation tool. Experimental tests have been carried out for the same parameters to validate the simulation model using a prototype assembly which is close to the system and developed in-house. The simulation results and experimental test results are found to be in good agreement. The effect of damping orifice size in the regulators and the varying tank ullage volume are studied and the obtained results are presented in the paper. The developed model serves as an ultimate a valid tool for understanding the system behavior under different operating conditions of mass flow rate, ullage volume, temperature and system operation sequence. Abbreviations EDM: electro discharge machining; OHPR: oxygen high pressure regulator; OLPR: oxygen low pressure regulator; CMM: coordinate measuring machine; OPHPR: outlet pressure of oxygen high pressure regulator; OPLPR: outlet pressure of oxygen low pressure regulator; IPGBSPS: inlet pressure of gas bottle storage pressure system; GHe: gaseous helium; AMESim: advanced modeling environment for performing simulations; FSO: full scale output; POV: pneumatically operated valve; EP: electro pneumatic; MATLAB: matrix laboratory; AISI: American iron and steel institute

AVO, near and far - the end of the trend?

This paper gives a brief overview of the history of the well-known and famous ‘background trend’ in AVO theory, which also goes by the names ‘lithology trend’, ‘fluid line’ and sometimes ‘noise trend’. Whereas the discovery of the trend met with euphoria, stirring hopes that it would become much easier to detect hydrocarbons, this promise has hardly been fulfilled. One of the problems was (and is) that the trend is much steeper than what theory based on rock properties predicts. This paper explains why and how the trend can be so steep. It explains how a clear trend emerges regardless of lithology, hydrocarbons or even noise. Any contribution from lithology or pore fluid, if it exists, will be smaller and often completely drowned by what I call the ‘transformation trend’.

Hydraulic Modal Analysis in Theory and Practice

Theoretical and experimental modal analyses are treated for hydraulic systems modeled by discrete capacities, inductances, resistances, and fluid lines with dynamic laminar flow. Based on an approximate multi-degrees-of-freedom description, it is shown how hydraulic natural frequencies, damping ratios, and mode shapes can be identified from measured frequency response functions between flow rate excitation and pressure response. Experiments are presented for a pipeline system that includes three side branches and an accumulator. In view of practical applications, two different types of servovalve excitation as well as impact hammer excitation are considered. Pressure is measured by 19 sensors throughout the system. Results are compared in terms of frequency response functions between 50 and 850 Hz, the first five hydraulic modes, and weighted auto modal assurance criteria of experimental mode shapes. Out of the tested excitation devices, the servovalve is clearly preferred; if valves cannot be used, the impact hammer offers a reasonable workaround. For a reduced number of five sensors, different sensor arrangements are assessed by the respective weighted auto modal assurance criteria of experimental mode shapes. A theoretical hydraulic modal model provides a similar assessment. The quality of the theoretical model is confirmed by the weighted modal assurance criterion of theoretical and experimental mode shapes from servovalve excitation.

Closed vortex lines in fluid and gas

Исследуется непрерывное течение жидкости и газа с замкнутыми вихревыми трубками. Рассмотрена циркуляция вдоль вихревой линии отношения плотности равнодействующей всех сил (приложенных к жидкости или газу) к плотности жидкости или газа. Она совпадает с циркуляцией по той же вихревой линии частной производной вектора скорости по времени и поэтому для стационарных течений равна нулю на любой замкнутой вихревой линии. Для нестационарных течений рассмотрены вихревые трубки, которые остаются замкнутыми по крайней мере в течение некоторого интервала времени. Обнаружена неизвестная ранее закономерность, состоящая в том, что в каждый фиксированный момент времени такая циркуляция одинакова для всех замкнутых вихревых линий, составляющих вихревую трубку. Указанная закономерность верна для течений сжимаемых и несжимаемых, вязких (различных реологий) и невязких жидкостей в поле потенциальных и непотенциальных внешних массовых сил. Поскольку эта закономерность не заложена в современные численные алгоритмы, она может использоваться для верификации численных расчетов нестационарных течений с замкнутыми вихревыми трубками путем проверки равенства циркуляций на разных замкнутых вихревых линиях (в одной трубке). Выражение для плотности распределения равнодействующей всех сил, приложенных к жидкости или газу, может содержать производные высших порядков. В то же время выражение для частной производной вектора скорости по времени и выражение для вектора завихренности, который необходим для построения вихревой линии, содержат только первые производные, что позволяет использовать обнаруженную закономерность для верификации расчетов, проведенных методами не только высокого, но и низкого порядков.

Research of modes and work of a combined unit for subsoil application of protective-stimulating liquids in spaces between rows of gardens and vineyards

The combined unit is used for tillage and subsurface belt application of protective and stimulating liquids and microorganisms into the soil. New technology offers for the task to use pneumatic slotted sprayers with jet-forming device that is linked with a compressor that delivers air to transform the operation fluid from the tank in the aerial-droplet jet processing lower layers of the soil simultaneously with cultivation. Protective shields save the sprayer from deformation and breakage. To obtain the required range of the jet, the angle of inclination of the sprayer is adjusted. The supply line of operation fluid has an equalizing capacity to change the flow rate of the operation fluid. The basis of the development of sprayers was the task of development of a plane-parallel jet capable of spreading to a distance to 2 m with an adjustable width of a grip m/s. there were conducted the researches of performance (charge) of pneumatic slotted sprayer depending on air pressure given to in slotted nozzles of the sprayer.

Impact of pore fluid heterogeneities on angle-dependent reflectivity in poroelastic layers: A study driven by seismic petrophysics

The present study demonstrates the application of seismic petrophysics and amplitude versus angle (AVA) forward modeling to identify the reservoir fluids, discriminate their saturation levels and natural gas composition. Two case studies of the Lumshiwal Formation (mainly sandstone) of the Lower Cretaceous age have been studied from the Kohat Sub-basin and the Middle Indus Basin of Pakistan. The conventional angle-dependent reflection amplitudes such as P converted P (RPP) and S (RPS), S converted S (RSS) and P (RSP) and newly developed AVA attributes (deltaRPP, deltaRPs, deltaRSS and deltaRSP) ) are analyzed at different gas saturation levels in the reservoir rock. These attributes are generated by taking the differences between the water wet reflection coefficient and the reflection coefficient at unknown gas saturation. Intercept (A) and gradient (B) attributes are also computed and cross-plotted at different gas compositions and gas/water scenarios to define the AVO class of reservoir sands. The numerical simulation reveals that deltaRPP, deltaRPS, deltaRSS and deltaRSP are good indicators and able to distinguish low and high gas saturation with a high level of confidence as compared to conventional reflection amplitudes such as P-P, P-S, S-S and S-P. In A-B cross-plots, the gas lines move towards the fluid (wet) lines as the proportion of heavier gases increase in the Lumshiwal Sands. Because of the upper contacts with different sedimentary rocks (Shale/Limestone) in both wells, the same reservoir sand exhibits different response similar to AVO classes like class I and class IV. This study will help to analyze gas sands by using amplitude based attributes as direct gas indicators in further gas drilling wells in clastic successions.

Risk factors associated with nosocomial infections in the Neonatal Intensive Care Unit at Mahatma Gandhi Memorial hospital between 2014 and 2015

Background: Nosocomial infections are one of the main causes of neonatal morbidity and mortality in low- and middle-income countries. The neonatal intensive care unit is a suitable environment for disseminating infections. The aim of this study was to identify risk factors associated with having a nosocomial infection in the neonatal intensive care unit at Mahatma Gandhi Memorial hospital between 2014 and 2015.Methods: An observational, analytical case-control study was conducted at the neonatal intensive care unit at Mahatma Gandhi Memorial hospital in 2017 following ethical approval (BE336/16). A retrospective review of medical records for a sample size of 144 cases and 144 matched controls from 2014 to 2015 was analysed. Descriptive statistics were presented and multivariate conditional logistic regression was used to determine associations between the independent variables and having a nosocomial infection.Results: A total of 144 neonates developed nosocomial infections as proven by positive cultures with Klebsiella pneumoniae being most frequent (n = 60; 41.67%). On multivariate logistic regression analysis, multiple deliveries, low birth weight, respiratory distress, prematurity, neonatal jaundice, hyaline membrane disease, the use of total parenteral nutrition, blood transfusion and surfactant administration, immediate use of oxygen and intravenous fluid and central line insertion were significantly associated with having a nosocomial infection (p ≤ 0.001).Conclusion: Neonatal-related factors and treatment modalities were identified as factors that increased the risk for nosocomial infections. A review of treatment modalities and related infection prevention and control in neonatal management are the key to prevention, early detection and management of nosocomial infections.

Proper Conformal Killing Vectors in Kantowski-Sachs Metric

This paper deals with the existence of proper conformal Killing vectors (CKVs) in Kantowski-Sachs metric. Subject to some integrability conditions, the general form of vector filed generating CKVs and the conformal factor is presented. The integrability conditions are solved generally as well as in some particular cases to show that the non-conformally flat Kantowski-Sachs metric admits two proper CKVs, while it admits a 15-dimensional Lie algebra of CKVs in the case when it becomes conformally flat. The inheriting conformal Killing vectors (ICKVs), which map fluid lines conformally, are also investigated.

Is it possible to reduce intra-hospital transport time for computed tomography evaluation in critically ill cases using the Easy Tube Arrange Device?

ObjectivePatients are often transported within the hospital, especially in cases of critical illness for which computed tomography (CT) is performed. Since increased transport time increases the risks of complications, reducing transport time is important for patient safety. This study aimed to evaluate the ability of our newly invented device, the Easy Tube Arrange Device (ETAD), to reduce transport time for CT evaluation in cases of critical illness.MethodsThis prospective randomized control study included 60 volunteers. Each participant arranged five or six intravenous fluid lines, monitoring lines (noninvasive blood pressure, electrocardiography, central venous pressure, arterial catheter), and therapeutic equipment (O2 supply device, Foley catheter) on a Resusci Anne mannequin. We measured transport time for the CT evaluation by using conventional and ETAD method.ResultsThe median transport time for CT evaluation was 488.50 seconds (95% confidence interval [CI], 462.75 to 514.75) and, 503.50 seconds (95% CI, 489.50 to 526.75) with 5 and 6 fluid lines using the conventional method and 364.50 seconds (95% CI, 335.00 to 388.75), and 363.50 seconds (95% CI, 331.75 to 377.75) with ETAD (all P<0.001). The time differences were 131.50 (95% CI, 89.25 to 174.50) and 148.00 (95% CI, 116.00 to 177.75) (all P<0.001).ConclusionThe transport time for CT evaluation was reduced using the ETAD, which would be expected to reduce the complications that may occur during transport in cases of critical illness.

Water Hammer Peak Pressures and Decay Rates of Transients in Smooth Lines With Turbulent Flow

Transient pressure peak values and decay rates associated with water hammer surges in fluid lines are investigated using an analytical method that has been formulated, in a previous publication, to simulate pressure transients in turbulent flow. The method agrees quite well with method of characteristics (MOC) simulations of unsteady friction models and has been verified with experimental data available for Reynolds numbers out to 15,800. The method is based on the formulation of ordinary differential equations from the frequency response of a pressure transfer function using an inverse frequency algorithm. The model is formulated by dividing the line into n-sections to distribute the turbulence resistance along the line at higher Reynolds numbers. In this paper, it will be demonstrated that convergence of the analytical solution is achieved with as few as 5–10 line sections for Reynolds numbers up to 200,000. The method not only provides for the use of conventional time domain solution algorithms for ordinary differential equations but also provides empirical equations for estimating peak surge pressures and transient decay rates as defined by eigenvalues. For typical sets of line and fluid properties, the trend of the damping ratio of the first or dominate mode of the pressure transients transfer function is found to be an approximate linear function of a dimensionless parameter that is a function of the Reynolds number. In addition, a reasonably accurate dimensionless trend formula for estimates of the normalized peak pressures is formulated and presented.

General connected and reconnected fields in plasmas

For plasma dynamics, more encompassing than the magnetohydrodynamical (MHD) approximation, the foundational concepts of “magnetic reconnection” may require deep revisions because, in the larger dynamics, magnetic field is no longer connected to the fluid lines; it is replaced by more general fields (one for each plasma specie) that are weighted combination of the electromagnetic and the thermal-vortical fields. We study the two-fluid plasma dynamics plasma expressed in two different sets of variables: the two-fluid (2F) description in terms of individual fluid velocities, and the one-fluid (1F) variables comprising the plasma bulk motion and plasma current. In the 2F description, a Connection Theorem is readily established; we show that, for each specie, there exists a Generalized (Magnetofluid/Electro-Vortic) field that is frozen-in the fluid and consequently remains, forever, connected to the flow. This field is an expression of the unification of the electromagnetic, and fluid forces (kinematic and the...

Structural behavior of supercritical fluids under confinement.

The existence of the Frenkel line in the supercritical regime of a Lennard-Jones (LJ) fluid shown through molecular dynamics (MD) simulations initially and later corroborated by experiments on argon opens up possibilities of understanding the structure and dynamics of supercritical fluids in general and of the Frenkel line in particular. The location of the Frenkel line, which demarcates two distinct physical states, liquidlike and gaslike within the supercritical regime, has been established through MD simulations of the velocity autocorrelation (VACF) and radial distribution function (RDF). We, in this article, explore the changes in the structural features of supercritical LJ fluid under partial confinement using atomistic walls. The study is carried out across the Frenkel line through a series of MD simulations considering a set of thermodynamics states in the supercritical regime (P=5000 bar, 240K≤T≤1500K) of argon well above the critical point. Confinement is partial, with atomistic walls located normal to z and extending to "infinity" along the x and y directions. In the "liquidlike" regime of the supercritical phase, particles are found to be distributed in distinct layers along the z axis with layer spacing less than one atomic diameter and the lateral RDF showing amorphous-like structure for specific spacings (packing frustration) and non-amorphous-like structure for other spacings. Increasing the rigidity of the atomistic walls is found to lead to stronger layering and increased structural order. For confinement with reflective walls, layers are found to form with one atomic diameter spacing and the lateral RDF showing close-packed structure for the smaller confinements. Translational order parameter and excess entropy assessment confirms the ordering taking place for atomistic wall and reflective wall confinements. In the "gaslike" regime of the supercritical phase, particle distribution along the spacing and the lateral RDF exhibit features not significantly different from that due to normal gas regime. The heterogeneity across the Frenkel line, found to be present both in bulk and confined systems, might cause the breakdown of the universal scaling between structure and dynamics of fluids necessitating the determination of a unique relationship between them.

Comparison of Osteoconduction, cytocompatibility and corrosion protection performance of hydroxyapatite-calcium hydrogen phosphate composite coating synthesized in-situ through pulsed electro-deposition with varying amount of phase and crystallinity

In order to improve the surface biocompatibility, a composite coating of hydroxyapatite and calcium hydrogen phosphate was synthesized over 316 L grade of stainless steel through pulsed electro deposition. It was observed that relative phase composition and corresponding crystallinity vary with the deposition current density. Thus a detailed study with the help of simulated body fluid and MG63 cell line was carried out in order to compare their respective biocompatibility in terms osteoconduction and cytocompatibility. A detailed electrochemical behavior study was carried out to assess the corrosion behavior under contact with body fluid.Cell proliferation studies indicate that the coating deposited with a current density of 10 mA/cm2, which is having the highest weight percentage and crystallinity of hydroxyapatite phase, is the most preferable one for continuous, faster and interconnected cell growth. Also cell cytoskeletons spread in bigger areas around their nucleus with a strong interconnection between each other. The bio-mineralization study shows that on immersion of these coatings in simulated body fluid, coating obtained through 10 mA/cm2, trends to build up hydroxyapatite on its surface with 200 nm pores at initial 1–3 days. After 14 days of immersion, hydroxyapatite deposition trends to form a spherical shape of around 2 micron in radius which can accommodate larger surface area for tissue growth vis-à-vis better bonding, as compared to other coating surfaces. The polarization resistance of 10 mA/cm2 coating is almost 10 times higher than the others and thus indicates its slower rate of corrosion under contact with simulated body fluid.

Administration of fentanyl via a slow intravenous fluid line compared with rapid bolus alleviates fentanyl-induced cough during general anesthesia induction.

Fentanyl-induced cough (FIC) is a common complication with a reported incidence from 18.0% to 74.4% during general anesthesia induction. FIC increases the intrathoracic pressure and risks of postoperative nausea and vomiting, yet available treatments are limited. This study was designed to investigate whether administering fentanyl via a slow intravenous fluid line can effectively alleviate FIC during induction of total intravenous general anesthesia. A total number of 1200 patients, aged 18-64 years, were enrolled, all of whom were American Society of Anesthesiologists (ASA) grade I or II undergoing scheduled surgeries. All patients received total intravenous general anesthesia, which was induced sequentially by midazolam, fentanyl, propofol, and cisatracurium injection. Patients were randomly assigned to receive fentanyl 3.5 μg/kg via direct injection (control group) or via a slow intravenous fluid line. FIC incidence and the severity grades were analyzed with the Mann-Whitney test. Other adverse reactions, such as hypotension, hypertension, bradycardia, tachycardia, hypoxemia, vomiting, and aspiration, during induction were also observed. The online clinical registration number of this study was ChiCTR-IOR-16009025. Compared with the control group, the incidence of FIC was significantly lower in the slow intravenous fluid line group during induction (9.1%, 95% confidence interval (CI): 6.7%-11.4% vs. 55.9%, 95% CI: 51.8%-60.0%, P=0.000), as were the severity grades (P=0.000). There were no statistical differences between the two groups with regard to other adverse reactions (P>0.05). The administration of fentanyl via a slow intravenous fluid line can alleviate FIC and its severity during induction for total intravenous general anesthesia. This method is simple, safe, and reliable, and deserves clinical expansion.

The importance of simulated lung fluid (SLF) extractions for a more relevant evaluation of the oxidative potential of particulate matter

Particulate matter (PM) induces oxidative stress in vivo, leading to adverse health effects. Oxidative potential (OP) of PM is increasingly studied as a relevant metric for health impact (instead of PM mass concentration) as much of the ambient particle mass do not contribute to PM toxicity. Several assays have been developed to quantify PM oxidative potential and a widely used one is the acellular dithiothreitol (DTT) assay. However in such assays, particles are usually extracted with methanol or Milli-Q water which is unrepresentative of physiological conditions. For this purpose, OPDTT measurements after simulated lung fluids (SLF) extraction, in order to look at the impact of simulated lung fluid constituents, were compared to Milli-Q water extraction measurements. Our major finding is a significant decrease of the OPDTT when the artificial lysosomal fluid (ALF) solution was used. Indeed, ligand compounds are present in the SLF solutions and some induce a decrease of the OP when compared to water extraction. Our results suggest that the effect of ligands and complexation in lining fluids towards PM contaminants probably has been underestimated and should be investigated further.

Reduced-order modelling of transient flow in transmission lines using distributed lumped parameters

AbstractDeveloped in this paper are mathematical models capturing the one-dimensional underdamped dynamics of confined fluid flow within cylindrical transmission lines. The resulting models are rational transfer functions with coefficients that are explicit functions of the fluid properties and line geometry. Unlike a traditional lumped-parameter approach, the accuracy of the fluid resonant frequencies predicted by the proposed models is precise and not a function of transmission line axial discretisation. Therefore, model order (complexity) is solely a function of the number of desired modes, which in turn influences pressure and flow predictions. The results are applicable to both laminar and turbulent flow. To develop the models, a distributed lumped-parameter approach is employed. Specifically, a quasi-steady state friction approximation is used within the governing partial differential equations. The solution to the linearised ordinary differential equations produces three transcendent transfer funct...

Numerical investigations of electrothermally actuated moving contact line dynamics: Effect of property contrasts

This article reports interfacial electro-thermo-chemical-hydrodynamics of binary fluids with contrasting viscosity, thermal conductivity, and electrical conductivity of fluids under AC electrokinetics, called alternating current electrothermal (ACET) mechanism, over wetted substrates. The interfacial kinetics of the two phases are modulated by the coupled influence of electrothermal, viscous, and capillary forces. Numerical investigations of contact line dynamics reveal that at low viscosity of displaced fluid, viscous drag force significantly reduces leading to faster progression of the contact line. Larger viscous drag force at higher viscosity of the displaced fluid resists the interface motion to travel along the capillary. ACET forces are the direct consequences of the thermal and electric fields. For low thermal conductivity of the displaced fluid, the temperature gradient becomes much stronger leading to higher ACET forces and contact line velocity. Below a threshold limit of thermal conductivity, stronger electrothermal forces cause misbalance between contact line velocity and bulk fluid velocity, which, in turn, trigger an interesting phenomena of interface breaking. Mismatch in electrical conductivity generates electrical stresses across the interface that deforms the interface profile and causes boosting impact across the interface leading to an increase in contact line velocity. The net force across the interface changes the direction depending on the deviation of electrical conductivity ratio from unity. Finally, we observe that larger channel height and wider electrode spacing decrease the net force on the bulk fluid and contact line velocity.

Just culture: A case study of accountability relationship boundaries influence on safety in HIGH-consequence industries

In high-consequence industries the desire of many managers to “hold someone accountable” for errors remains a barrier to advancing meaningful safety agendas. The misconception that clear lines of accountability can and do exist, and that employees who cross the line between acceptable and unacceptable behavior should be punished, fails to recognize the different types of accountability relationships negotiated by employees every day. Such judgments run counter to the concept and practice of a just culture. Examination of the four types of accountability relationships, potentially seen within any just culture - hierarchical, legal, professional, and political, reveal the potential for the lines of accountability to frequently blur. This opaqueness is seen in numerous accidents which reveal the conflicting effects employees in high-consequence industries face as they move between and across these accountability boundaries. We use a case study, as a glimpse into the world of practice of aviation to illustrate the conflict, and double- binds, created as those in high-consequence industries negotiate the fluid lines of accountability relationship boundaries. This germane example is the crash of Swissair Flight 111, near Halifax, Nova Scotia, in 1998. Here we offer dialogue to aid in understanding the influence accountability relationships have on safety, and how employee behavioral expectations shift in accordance. We propose that this examination will help redefine accountability boundaries that support a just culture within dynamic high-consequence industries.

Analysis of the Thermal and Hydraulic Stimulation Program at Raft River, Idaho

The Raft River geothermal field, located in southern Idaho, roughly 100 miles northwest of Salt Lake City, is the site of a Department of Energy Enhanced Geothermal System project designed to develop new techniques for enhancing the permeability of geothermal wells. RRG-9 ST1, the target stimulation well, was drilled to a measured depth of 5962 ft. and cased to 5551 ft. The open-hole section of the well penetrates Precambrian quartzite and quartz monzonite. The well encountered a temperature of 282 °F at its base. Thermal and hydraulic stimulation was initiated in June 2013. Several injection strategies have been employed. These strategies have included the continuous injection of water at temperatures ranging from 53 to 115 °F at wellhead pressures of approximately 275 psi and three short-term hydraulic stimulations at pressures up to approximately 1150 psi. Flow rates, wellhead and line pressures and fluid temperatures are measured continuously. These data are being utilized to assess the effectiveness of the stimulation program. As of August 2014, nearly 90 million gallons have been injected. A modified Hall plot has been used to characterize the relationships between the bottom-hole flowing pressure and the cumulative injection fluid volume. The data indicate that the skin factor is decreased, and/or the permeability around the wellbore has increased since the stimulation program was initiated. The injectivity index also indicates a positive improvement with values ranging from 0.15 gal/min psi in July 2013 to 1.73 gal/min psi in February 2015. Absolute flow rates have increased from approximately 20 to 475 gpm by February 2 2015. Geologic, downhole temperature and seismic data suggest the injected fluid enters a fracture zone at 5650 ft and then travels upward to a permeable horizon at the contact between the Precambrian rocks and the overlying Tertiary sedimentary and volcanic deposits. The reservoir simulation program FALCON developed at the Idaho National Laboratory is being used to simulate and visualize the effects of the injection. The simulation model uses a discrete fracture network generated for RRG-9 using acoustic borehole imaging and analysis of microseismic activity. By adjusting the permeability of the fractures, a pressure history match for the first part of the stimulation program was obtained. The results of this model indicate that hydraulic fracturing is the dominant mechanism for permeability improvement for this part of the stimulation program.