Degree Of Blockage Research Articles

Surgeon-administered ultrasound-guided combined popliteal sciatic nerve and adductor canal block in fixation of trimalleolar fracture

Introduction: Combined popliteal sciatic nerve and adductor canal block under ultrasound guidance has been described as a safe and effective mean of regional anesthesia for foot and ankle surgery. Limited studies have shown its effectiveness while performed by surgeons. This study aims to assess the effectiveness and safety for this mode of regional anesthesia while carried out by orthopedic surgeons. Method: Patients presented to our unit with trimalleolar fracture of ankle who underwent operation under surgeon-administered ultrasound-guided combined popliteal sciatic nerve and adductor canal block were evaluated in this study. A total of 13 patients with mean age of 57.8 were included. Data regarding the diagnosis, pattern of injuries, comorbidities in American Society of Anesthesiologists Classification, duration of operation, blood loss, intraoperative pain control in visual analog scale (VAS), degree of motor blockage, postoperative pain control and hospital length of stay were collected and evaluated. Result: All patients experienced complete anesthesia with VAS 0 and complete motor blockage throughout the operation. Average operative time was 179 min. Postoperative pain control was satisfactory. There was no regional anesthesia related complication arise. Conclusion: Surgeon-administered ultrasound-guided combined popliteal sciatic nerve and adductor canal block is a safe and effective mean to provide anesthesia for trimalleolar fracture fixation according to our experience.

Exploring the Relationships Between Clinical Examination Findings, Subjective Reported Symptoms and Objective Nasal Patency Measures in Nasal Obstruction: A Baseline NAIROS Sub-Study Analysis.

The role of objective nasal airflow measures using peak nasal inspiratory flow (PNIF) and rhinospirometry in supporting clinical examination findings when offering patients septoplasty remain undefined. To explore the baseline relationships between clinical examination findings, subjective reported symptoms and objective nasal patency measures in nasal obstruction. This is a sub-study of the NAIROS trial. Participants with nasal obstruction secondary to septal deviation were included in this NAIROS sub-study. The side of septal deviation, enlargement of inferior turbinate (IT), the need for IT reduction if septoplasty was being performed, the area of septum deflecting into the airway and observer rated airway block (ORAB-arbitrarily divided by <50% and >50% blockage) were assessed by clinicians. The subjective score of nasal obstruction was assessed using the Double Ordinal Assessed Subjective Scale (DOASS). Objective nasal patency measures (e.g., nasal partitioning ratio, [NPR] and PNIF) were measured using PNIF and rhinospirometry. The mean NPR for left-sided, both-sided and right-sided septal deviation was -0.35, -0.02 and 0.51, respectively (p < 0.001). There was very weak correlation between the requirement for IT reduction and PNIF change (0.13, p < 0.01). There was no difference in mean PNIF (94 L/min vs. 93 L/min) and mean DOASS (0.33 vs. 0.38) for participants with ORAB rated <50% and >50%. The mean NPR for participants with ORAB >50% was higher than for those with ORAB <50% (0.51 vs. 0.41, p = 0.002). There was strong correlation between the DOASS and NPR (+0.737, p < 0.001). The mean DOASS score for right-sided, both-sided and left-sided septal deviation was 0.32, 0.05 and -0.29, respectively (p < 0.001). This study identified strong relationships between the clinician rated side of septal deflection, the patient reported DOASS and the objective NPR measurements. NPR and the clinician rated degree of airway blockage were concordant.

PERIODIC FOAMING DURING SELECTIVE ISOLATION OF HIGHLY PERMEABLE CHANNELS OF POROUS MEDIUM

Selective isolation of watered interlayers by forming barriers formed by highly viscous gels or insoluble precipitates does not always lead to the desired results. Field experience confirms that at some distance from the formed barrier, the filtration flow restores its configuration and the water injected into the formation again moves through highly permeable channels. An increase in the efficiency of flow deflection can be achieved by creating not a single barrier, but a whole sequence of alternating deep-penetrating insulating barriers, separated from each other by a certain distance in highly permeable pores. The paper presents the results of studies of quasi-periodic foaming in order to control mobility under conditions of selective isolation of water in pore channels of high permeability. Foaming occurs due to the in-bulk reaction between concentrated aqueous solutions of gas-generating and gas-generating solutions. Flow pattern of injected aqueous solutions of foaming reagents along current tubes is investigated. The task is to determine the space-time distribution of reagents in given zones of the porous medium. The problem of establishing the correlation between the spatial distribution of the gas formation zone and the dynamics of the gas formation process over time on the one hand, as well as the concentration of reactants, the diffusion rate (mutual diffusion), the gas generation rate and the probability of nucleation on the other hand was solved. The degree of flow blockage in highly permeable zones of the formation depends on the rate of in-situ foam generation and the simulation consists in the fact that it is similar to the law of filtration with a limiting gradient. The paper discusses the process of quasi-periodic gas formation during the movement of mixing solutions in porous media. In stationary filtration in a homogeneous porous medium, the process is described by the proposed system of equations. A system of equations is proposed that describes the movement of a liquid taking into account adsorption of reagents, diffusion and dynamics of the foaming reaction. The results obtained can serve as the basis for developing a method for controlling the water cut of porous media during waterflooding of oil formations. This, in turn, leads to the leveling of the displacement front and an increase in the completeness of coverage.

Study on causes and laws of crystallization blockage for dolomite tunnel drainage pipeline

AbstractIn order to study the crystallization blockage law and crystallization mechanism of dolomite tunnel drainage system, based on the indoor model test, the simulated crystal blockage and growth process were simulated. The phase composition and microstructure of the crystal were analyzed by energy‐dispersive X‐ray spectroscopy (EDS), scanning electron microscopy (SEM), and X‐ray diffraction (XRD). Combined with the pipeline crystal weighing, the crystal growth law and the internal cause of pipeline blockage were analyzed. The results show that the pipeline crystallization mechanism is divided into the first mechanism, the second mechanism, and the third mechanism. The crystallization blockage of the longitudinal and horizontal pipes are more serious, while the crystallization blockage of the ring pipes are less harmful. The crystallization is positively correlated with ion concentration, crystalline ions having a great influence on the blockage of pipeline crystallization, while noncrystalline ions having little influence. The crystal growth law is fast first and then slow, the crystallization affected by the coupling concentration of Cl−‐K+‐Na + ions, and positively correlated with the coupling concentration of CO32−‐SO42−‐Ca2+‐Mg2+‐Al3+ ions. Compared with the longitudinal pipes and the ring pipes, the horizontal pipes have more crystallization and higher degree of crystallization blockage per meter, while the crystallization degree of the longitudinal pipes are between the horizontal pipes and the ring pipes.

Role of exhaled carbon monoxide in assessment of chronic obstructive airway disease severity

BackgroundChronic obstructive pulmonary disease (COPD) is a critical public health issue. Spirometric measurements are used to diagnose chronic obstructive lung disease, as per the guidelines of the GOLD initiative. Post-bronchodilator forced expiratory volume in 1 s (FEV1) is a predictor of mortality from COPD and helps to classify the disease’s severity. Smoking contributes to the high levels of exhaled CO. Evidence suggests that the exhaled CO level in COPD patients varies with degree of blockage and can be used to assess treatment response. Estimating the exhaled CO level can help assess airway inflammation and severity of airflow obstruction in individuals with COPD.AimEvaluate role of exhaled CO in assessment of severity of COPD.Materials and methodsThis cross-sectional study included 132 patients who visited the outpatient clinics or were admitted to the Chest Department, Kasr Alainy Hospital, Faculty of Medicine, Cairo University. The study participants were divided into three groups: group 1 nonsmoker healthy control, group 2 smoker non-COPD, and group 3 smoker COPD which further divided according to GOLD 2023 into mild, moderate, and severe COPD. The smoking status, exhaled CO, and spirometry test including FEV1/FVC and FEV1 were measured for each patient.ResultsExhaled CO was significantly increased in the smoker group (mean 9.69, SD 3.11) compared to the nonsmoker group (mean 2.19, SD 0.98) with p-value < 0.001. Exhaled CO was also statistically significantly higher in the smoker COPD group (mean 10.45, SD 3.03) compared to the smoker non-COPD group (mean 7.05, SD 1.56) with p-value < 0.001. Although exhaled CO was increased in the severe COPD group compared to the mild and moderate group, there is no statistically significant difference between them.ConclusionExhaled CO is a fast, sensitive, noninvasive, and well-established method test that can be used to identify smokers from nonsmokers with 98.9% sensitivity at 4.5 cutoff value. Also, exhaled CO levels in COPD patients vary with different degrees of airway obstruction.

The application of surgeon-administered ultrasound-guided popliteal sciatic nerve block in foot and ankle injuries

Introduction Ultrasound-guided popliteal sciatic nerve block has been described as a safe and consistent form of regional anesthesia for foot and ankle surgery. Little studies have been performed to prove the effectiveness of surgeon self-administered regional anesthesia for foot and ankle injury requiring an operation. This study aimed to assess the applicability and safety in surgeon-administered ultrasound-guided popliteal sciatic nerve block in providing anesthesia for foot and ankle fracture. Material and Methods Patients with foot and ankle injury who underwent operation under surgeon-administered ultrasound-guided popliteal sciatic nerve block were evaluated in this retrospective study. A total of 7 patients (3 females and 4 males) with a mean age of 46) were evaluated by the diagnosis, side of injury, comorbidities in American Society of Anesthesiologists Classification (ASA), duration of operation, blood loss, pain control in visual analog scale (VAS) intra-operatively, degree of motor blockage, post-operative pain control and hospital length of stay. Result Average age of the study population was 46. Of all the patients, two of them were of ASA I four of them were of ASA II and one of them was of ASA III. Complete sensory and motor blockages were achieved for all patients. Average operative time was 117 min. Average blood loss was 16.4 mL. Average post-operative inpatient stay was 3.57 days. There was no regional anesthesia-related complication arising from the procedure. Conclusion Surgeon-administered popliteal sciatic nerve block is a safe procedure and can provide excellent pain control throughout the operation according to our experience. Foot and ankle fracture fixation can be performed by orthopedic surgeons under this technique.

CO2–Water–Rock Interaction and Its Influence on the Physical Properties of Continental Shale Oil Reservoirs

Shale oil resources are abundant, but reservoirs exhibit strong heterogeneity with extremely low porosity and permeability, and their development is challenging. Carbon dioxide (CO2) injection technology is crucial for efficient shale oil development. When CO2 is dissolved in reservoir formation water, it undergoes a series of physical and chemical reactions with various rock minerals present in the reservoir. These reactions not only modify the reservoir environment but also lead to precipitation that impacts the development of the oil reservoir. In this paper, the effects of water–rock interaction on core porosity and permeability during CO2 displacement are investigated by combining static and dynamic tests. The results reveal that the injection of CO2 into the core leads to reactions between CO2 and rock minerals upon dissolution in formation water. These reactions result in the formation of new minerals and the obstruction of clastic particles, thereby reducing core permeability. However, the generation of fine fractures through carbonic acid corrosion yields an increase in core permeability. The CO2–water–rock reaction is significantly influenced by the PV number, pressure, and temperature. As the injected PV number increases, the degree of pore throat plugging gradually increases. As the pressure increases, the volume of larger pore spaces gradually decreases, resulting in an increase in the degree of pore blockage. However, when the pressure exceeds 20 MPa, the degree of carbonic acid dissolution will be enhanced, resulting in the formation of small cracks and an increase in the volume of small pores. As the temperature reaches the critical point, the degree of blockage of macropores gradually increases, and the blockage of small pores also occurs, which eventually leads to a decrease in core porosity.

A COMPARATIVE DOSE-RESPONSE STUDY BETWEEN INTRATHECAL NALBUPHINE (0.8 MG, 1.4 MG) WITH BUPIVACAINE HEAVY 0.5% 3.5 CC IN LOWER ABDOMINAL SURGERIES

Aims: To study the efficacy of various doses of nalbuphine as an additive in sub-arachnoid block for lower abdominal surgeries. Methods: This comparative study was conducted by the addition of two different doses of nalbuphine as an adjuvant: 0.8 mg nalbuphine hydrochloride to 0.5% bupivacaine (heavy) and 1.4 mg nalbuphine hydrochloride to 0.5% bupivacaine (heavy), the onset, maximum level, duration of sensory blockade, motor blockade, and hemodynamic parameters were studied. Results: It was discovered that group B (1.4 mg of nalbuphine added to 0.5% bupivacaine [H]) results in a later onset and greater degree of sensory and motor blockage. This group also considerably extended the time of analgesia, sensory and motor blockage, and both. The statistical examination of the mean blood pressure and mean pulse rate, together with the study of hemodynamic parameters, revealed that the p value was significant for the mean pulse rate and diastolic blood pressure but negligible for the systolic blood pressure. Conclusion: It can be concluded that intrathecal 0.5% bupivacaine (H)+nalbuphine (1.4 mg) when compared to intrathecal 0.5% bupivacaine (H)+nalbuphine (0.8 mg) in the patients undergoing lower abdominal surgeries.

Experimental and Statistical Study on the Formation Characteristics and Discrimination Criteria of River Blockages Caused by Landslides

The discrimination of river blockages is very important for the risk assessment of landslide disasters and secondary hazards. Experimental studies and statistical analyses were carried out to explore the formation process and discriminant criteria of river blockages caused by landslides. An adjustable slide chute was designed and built to conduct forty-five landslide experiments. According to the experimental results, river blockage was identified as having six types based on the differences between the water depth and the height of the landslide dam, and the degree of river blockage increased from 70% to 100% as the chute angle, particle size, and landslide volume increased. It is also found that landslide volume controls the landslide dam height and degree of blockage, and particle size and slide angle control both the landslide velocity as it enters the river and the cross-section shape of the landslide dam. To investigate more influence factors, a statistical investigation of 60 real landslide cases was carried out, and it revealed that some geometric attributes related to landslide volume have the highest correlation with river blockage, especially landslide thickness. Finally, an improved probability model was proposed to assess the possibility of complete blockage, and it has overall accuracies of 91.1% and 83.3% when applied to predict experimental landslide cases and real landslide cases, respectively.

Experimental investigations on the jet flow field propagation characteristics and ignition mechanisms of stoichiometric CH4/O2/N2 premixed turbulent jet flames

The jet flow field (JFF) and flame propagation of stoichiometric CH4/O2/N2 mixtures under variable thermodynamic conditions were investigated experimentally using Schlieren and natural flame luminosity imaging techniques. A two-color method by wavelength integration was used to characterize the temperature field. The turbulent flame velocity (ST), Damköhler number (Da), Reynolds number (Re), and jet flame regime were explored by a combination of experimental data and theoretical calculations. The flame morphology shows that the propagation process can be subdivided into three stages: first, the JFF enters the main combustion chamber, then the flame propagates in the JFF, and finally, the JFF disappears after the flame front and the JFF front coincide. The vortex motion changes the thin reaction zone and the local high temperature region distribution. The normal jet shifts to the Mach disk jet at higher oxygen content. The ignition location changes from the jet tail to the shear layer. The top secondary vortex is more likely to generate at higher ambient temperatures, which enhances the ignition probability on the flame top. In addition, the degree of orifice blockage determines the jet flame type. Since the initial jet flame is more affected by orifice blockage, the variation in ST is strongly influenced by the change in the length-scale ratio. As the jet flame gradually moves away from the orifice, ST is mainly governed by turbulence intensity. Finally, a strong correlation between the Re number and Da number of the jet flame was found.

Study on the flow mechanism and frequency characteristics of rales in lower respiratory tract.

The frequency characteristics of lung sounds have great significance for noninvasive diagnosis of respiratory diseases. The rales in the lower respiratory tract region that can provide rich information about symptoms of respiratory diseases are not clear. In this paper, a three-dimensional idealized bifurcated lower respiratory tract geometric model, which contains 3rd to 13th generation (G3-G13) bronchi is constructed, where , and then the large eddy simulation and volume of fluid are used to study the fluid flow characteristics. Ffowcs Williams and Hawkings model are subsequently used to study the frequency characteristics of rale of different generations of bronchi. The results showed that bronchial blockage and sputum movement will enhance the turbulence intensity and vortex shedding intensity of flow. The dominant frequency and highest value of sound pressure level (SPL) of rhonchi/moist crackles decrease with the increase of bronchial generation. The change rates of dominant frequency of rhonchi/moist crackles in adjacent generations were 5.0 ± 0.1~9.1 ± 0.2% and 3.1 ± 0.1~11.9 ± 0.3%, respectively, which is concentrated in 290~420Hz and 200~300Hz, respectively. The change rates of SPL of rhonchi/moist crackles were 8.8 ± 0.1~15.7 ± 0.1% and 7.1 ± 0.1~19.5 ± 0.2%, respectively, which is concentrated in 28~50dB and 16~32dB, respectively. In the same generation of bronchus (e.g., G8, G9) with the same degree of initial blockage, the dominant frequency and SPL of moist crackles can be 3.7 ± 0.2% and 4.5 ± 0.3% slightly higher than that of rhonchi, respectively. This research is conducive to the establishment of a rapid and accurate noninvasive diagnosis system for respiratory diseases.

Effects of ultrasonic oscillations on permeability of rocks during the paraffinic oil flow

The paper shows that depending on the degree of blockage of the pore space due to paraffin precipitation the ultrasonic treatment has different effects. If a part of permeable channels is irreversibly deteriorated, then the activation of elastic oscillations contributes to postponing the moment of blocking the remaining part and helps to maintain the oil flow through a sample at a constant level. Without additional means an ultrasonic treatment does not have a significant effect in the case of strong blockage of permeable channels. If elastic oscillations are imposed on the rock and liquid at the initial moment of flow, then the porous space of the rock will be preserved from the precipitation of paraffins.

Semianalytical Modeling for Multiphase Flow in a Fractured Low-Permeability Gas Condensate Reservoir.

During the production of fractured low-permeability gas condensate reservoir (FLPGCR), a phase transition takes place in both the formation and wellbore, resulting in multiphase flow when the pressure drops below the dew point pressure. Additionally, the presence of fractures causes the formation of stress-sensitive characteristics. Nevertheless, traditional analytical models, such as the two-region model or three-region model, overlook the coupling impact of the above factors, which could lead to incorrect pressure transient response and erroneous estimation of well and formation parameters. Therefore, this work presents a semianalytical model for an FLPGCR considering the effects of multiphase flow, stress-sensitive, and wellbore phase redistribution. The gas condensate reservoir is divided into N banks, and the radial fluid saturation variation is modeled by multiple annular reservoirs with a constant saturation in each annular reservoir. The behavior of a fractured reservoir is modeled by using the dual-porosity model. The Pedrosa transform was utilized to address the nonlinear differential equation arising from stress-sensitive behavior. To verify the semianalytical solution, it was compared with numerical simulation results from CMG. The results showed that there are 10 flow regimes for the proposed model. The shape of the type curve has the potential to identify the degree of blockage within the FLPGCR. The wellbore phase redistribution only affects the first transitional-flow regime, which slows the rate of pressure drop. The stress sensitivity will lead to the upward characteristic of the curve in a later stage. More attention should be paid to the upward pressure derivative curve at late times, which is conventionally regarded as the effect of a closed boundary when it may not be the case. In addition, the shape factor and composite radius may obscure the radial flow regime. Finally, the proposed model was applied to interpret the pressure measurements recorded from the Bohai field in China, which exhibits a better fitting quality than the traditional models.

Dual catheter and double-lumen cerebrospinal fluid shunt systems with backflow mechanisms.

We previously developed a novel functional benchtop apparatus to simulate catheter occlusion in vitro utilizing avian vitelline membrane and chalaza to test catheter designs and de-obstruction techniques. Here, we study the integration of double-lumen catheter-mediated backflow in the shunt system assembly and its potential for an in-line de-obstruction of an obstructed ventricular catheter. A double-lumen catheter was connected to a standard proximal shunt catheter for all trials. One limb of the double-lumen catheter was connected to the backflow mechanisms and allowed to loop back for fluid access. A micropump and a bi-corporal electromagnetic pump were utilized to provide various degrees of backflow at predetermined intervals. Flow rates were measured after initial occlusion and after implementation of the backflow mechanisms, and degrees of catheter blockage was calculated as a percentage of the unoccluded flow rate. Flow visualization was also used. In baseline blockage of less than 50%, the average occluding agent weighed 0.3-0.6 g with baseline flow rates of 8.5-11.9 mL/min. After 5 min of backflow using a micropump, the degree of blockage was reduced in 50% of trials. Additional backflow for 5 min did not provide further improvements in flow rate. In baseline blockage of greater than 50%, the average occluding agent weighed 0.8-1.3 g with baseline flow rates of 1.1-4.2 mL/min. After 5 min of backflow, the system demonstrated a decreased blockage in 20% of trials; additional backflow for 5 min further improved the flow rate in 40% of the total trials. Only magnetic plates provided enough force to provide pulsatile backflow in the bi-corporal electromagnetic system. The preliminary results of connecting a standard proximal catheter in series with a double-lumen catheter show a slight change in the percent occlusion from the baseline status several times when the retrograde flow occurred via one limb of the catheter. Additionally, the de-obstruction seems related to the length of the interval of the backflow and the initial percentage occlusion of the proximal catheter. The statistical analysis does not reveal a statistically significant reduction in occlusion in the proximal catheter with either backflow interval.

COMPARISION OF DIFFERENT DOSES OF CLONIDINE ADDED TO INTRATHECAL BUPIVACAINE IN ORTHOPEDICS SURGERY

Background: Intrathecal Clonidine is a very safe nonopioid adjuvant to local anaesthetics to prolong the duration of analgesia without any major side effects. Objective: The purpose of the present study is to evaluate the “ COMPARISION OF DIFFERENT DOSES OF CLONIDINE ADDED TO INTRATHECAL BUPIVACAINE IN ORTHOPEDICS SURGERY” Material &amp;Method: ATotal of 60 aduit patients scheduled to undergo lower limb sugeries were ramdonly allocated into either of two group of 30 pateints. Group A: Bupivacaine heavy (0.5%) 2.5ml +30mcg Clonidine, total volume 2.8 ml Group B: Bupivacaine heavy (0.5%) 2.5ml +45mcg Clonidine, total volume 2.8 ml Onset &amp; duration of sensory blockage, Degree of motor blockage, Degree of sedation, Intraoparative heamodynamics. Side effect or any other complication were noted. Result: The mean time of onset of sensory &amp; motor block was less in higher dose added to bupivacaine . The Duration of sensory blockage was signicantly prolonged in Group B 367.26±36.60 min as compared to Group A 200.13±15.70 min . The Duration of motor blockage was signicantly prolonged in Group B 227.86± 22.49min as compared to Group A 176±12.91 min. Conclusions: The addition of intrathecal clonidine 30mcg to small dose of bupivacaine increased the spread , duration of analgesia, &amp; produced effective spinal anesthesia with stable heamodynamis.

Investigation of Flow and Spectral Characteristics in a Flow-Flow Hydrodynamic Generator of the Flat Type with Changes in the Degree of Flow Blockage

Investigation of Flow and Spectral Characteristics in a Flow-Flow Hydrodynamic Generator of the Flat Type with Changes in the Degree of Flow Blockage

Investigation of Flow and Spectral Characteristics in a Flow-Flow Hydrodynamic Generator of the Flat Type with Changes in the Degree of Flow Blockage

The paper presents the results of studying the flow past cylindrical bodies located in a flattype flow-through hydrodynamic generator. The result were obtained on the hydrodynamic test bench of the experimental base of the Scientific Center of the Mechanical Engineering Research Institute of the Russian Academy of Sciences with the degree of flow blockage by the bluff bodies St /S0 = 10– 82%, the Re numbers (0.5–5) × 105 , and the inlet pressure Рin= 0.1–0.9 MPa. It was found that at certain values of the inlet/outlet pressure ratio, which are constant for each of the degrees of flow blockage, powerful resonant-type pressure peaks arise at frequencies of 0.5–5 kHz with the amplitude more than 4–5 times higher than the maximum inlet pressure.

Improvement in Nasal Obstruction and Quality of Life after Nasal Septoplasty with Turbinoplasty: A Pre- and Post-study.

Introduction Septoplasty and turbinoplasty are common surgical interventions used to relieve nasal obstructive symptoms. Since it is difficult to measure the degree of nasal blockage, current literature wonders about the frequent performance of these procedures. Objective To evaluate the perceived change in the nasal obstruction and the quality of life (QoL) of patients that underwent a septoplasty along with a turbinoplasty by applying subjective scales, to describe the correlation between those scales, and to study the impact of clinical factors in the postoperative outcomes. Methods Prospective observational study. The Nasal Obstruction Symptom Evaluation (NOSE), the Visual Analog Scale (VAS), and the Glasgow Benefit Inventory (GBI) were assessed. The paired sample Wilcoxon test was used to evaluate the difference between the pre- and postoperative surveys. The correlation coefficient between the subjective scales was calculated. A quantile regression was performed to evaluate the effect of surgery on the results adjusted for clinical and demographic variables. Results A total of 115 patients were interviewed. Postoperative NOSE scores were 45 points lower (95% confidence interval [CI]: - 53.53-- 35.46; p < 0.001) in comparison with the NOSE preoperative scores. Obesity was the only statistically significant factor associated with worse outcomes. Additionally, we found a high correlation between the NOSE and VAS scores and a negative correlation between the GBI and postoperative VAS scores. Conclusion Nasal septoplasty, when paired with a turbinoplasty, decreases nasal obstruction and improves QoL. Obesity was associated with worse results. There was a strong correlation between the NOSE and the VAS results and between the GBI and postoperative VAS results.

A Multicriteria Decision-Making Framework for Access Point Selection in Hybrid LiFi/WiFi Networks Using Integrated AHP-VIKOR Technique.

Since light fidelity (LiFi) and wireless fidelity (WiFi) do not interfere with one another, a LiFi/WiFi hybrid network may provide superior performance to existing wireless options. With many users and constant changes, a network can easily become overloaded, leading to slowdowns and fluctuations in data transfer speeds. Access point assignment (APA) is required with the increase of users, which can negatively impact the system performance and quality-of-service (QoS) due to mobility and line-of-sight (LOS) blockage. Many variables could influence the APA process; these variables are considered as criteria, such as the network capacity, the degree of blockage, the speed of the connected user, etc. Unlike conditional APA methods, recent studies have considered treating these variables as "evaluation criteria". Considering these criteria can offer better and more accurate results, eventually enhancing the APA process and QoS. However, the variety of these criteria, the conflict amongst them, their weights (importance), and priority have not been addressed so far. Moreover, treating the criteria equally might result in inaccurate outcomes. Therefore, to solve this issue, it is essential to investigate the impact of each criterion on the APA process. In this work, a multicriteria decision-making (MCDM) problem is formulated to determine a network-level selection for each user over a period of time The decision problem is modeled as a hierarchy that fragments a problem into a hierarchy of simple and small subproblems, and the selection of the AP network among various alternatives is a considered as an MCDM problem. Based on the previous works, we are not aware of any previous research attempts using MCDM methods in the LiFi research area for network selection. Therefore, this work proposes an access point assignment framework using an MCDM approach for users in a hybrid LiFi/WiFi network. The experiment was conducted based on four phases: Five criteria were identified and evaluated with eleven APs (alternatives). The outcome of this phase was used to build the decision matrix and an MCDM was developed and built based on user mobility and blockages with various scenarios using all the criteria; The analytic hierarchy process (AHP) was employed to identify the criterion of the subjective weights of each criterion and to determine the degree of importance supported by experts' judgement. Determining the weights in the AHP process considered various investigations, including the consistency ratio (CR) and the AHP consensus indicator, which is calculated using the rank-based maximum likelihood method (RGMM) and Shannon entropy techniques. The VIekriteri-Jumsko KOmpromisno Rangiranje (VIKOR) method is adopted in the selection of the optimal AP for the proper selection of whether a LiFi or WiFi AP must serve the users. The integrated AHP-VIKOR was effective for solving the APA and was the best solution based on using weighted criteria simultaneously. Moreover, the ranking outcomes of the developed integrated AHP-VIKOR approach were evaluated using sensitivity analysis. The result of this work takes the APA for hybrid LiFi networks to a new perspective.

Quantitative Prediction Method of Liquid Retention Based on Nuclear Magnetic Resonance

For tight gas reservoirs such as water-sensitive and low permeability, the incoming fluids are the most important external factors that damage oil and gas reservoirs. The liquid phase retention has become an important influence factor of production capacity. At present, the water blockage damage degree is often used to evaluate the liquid phase retention degree. Therefore, based on the study of fractal dimension by a NMR (nuclear magnetic resonance) experiment, using the existing formula of the fractal calculation of the relative permeability curve, this paper improves the relevant formula for calculating water blockage damage for NMR and studies the relative permeability curve and water blockage damage rate of tight gas reservoirs. According to the calculation results, the fractal dimension of the samples is 2.3551–2.7417, and the average value is 2.492. This shows that the micro-pore structure of core samples is relatively complex with medium heterogeneity. Through the analysis of the relative permeability curve, it can be deduced that the rocks in this block have strong hydrophilicity, and the gas–water two-phase seepages in this block strongly interfere with each other. Besides, the comparative analysis shows that the method of calculating water blockage damage rate is accurate and the average error is only 4.59%. The average damage degree of water blockage in this block is moderate water blockage damage. The results of the parametric analysis also demonstrate that irreducible water saturation and pore-throat structure relationship are the key factors governing the water blockage degree, which determines the damage degree of foreign liquid retention to reservoirs.