Skin Factor Research Articles

Improved Injection Schedules of CO2 for Pohang Basin, Yeongil Bay, South Korea: Regarding Field Security and Injection Effectiveness

Abstract Yeongil bay is a basin located in Pohang, South Korea. Numerous projects and researches have been conducted for carbon capture and storage in Yeongil bay. The objectives of most of studies were shifted from enhancing injection efficiency to ensuring safety of carbon dioxide (CO2) storage after the Pohang earthquake occurrence in 2017. In this research, we present a stepwise CO2 injection scenario, which gradually increases injection rate during early stage of CO2 injection period. Furthermore, we conduct sensitivity analyses on an optimal stepwise CO2 injection scenario, based on the variations of permeability, well skin factor, and boundary condition between the storage site and aquifer. In conclusion, we can reduce the duration of CO2 injection compared to other injection scenarios which have suggested by previous studies with the same safety conditions and total amount of CO2 injected.

TECHNOLOGICAL COMPLICATIONS (FORMATION DAMAGE) DURING CO2 INJECTION FOR ENHANCED OIL RECOVERY. PART 3. PREVENTING AND REPAIRING FORMATION DAMAGE CAUSED BY CO2 INJECTION

The article considers technological complications arising during CO2 injection for enhanced oil recovery, with a focus on the formation of asphaltenes in the pore space and their negative impact on production efficiency. Formation of asphaltene solids in the reservoir leads to an increase in the skin factor, their removal to the wells, accumulation in the wellbore and on the surface of the equipment, which reduces oil flow to the well and requires expensive remedial work. Methods of identification and monitoring of asphaltene deposits are considered. Results of laboratory studies confirming the difficulty of quantitative assessment of asphaltene deposition are given, as well as practical examples of application of various technologies for their prevention and removal. Methods including the use of inhibitors and dispersants and the use of aromatic solvents to restore reservoir properties are reviewed. It also emphasises the need for continuous monitoring of field operations and the development of effective asphaltene management methods, which is critical to improving the economic feasibility of CO2 injection projects.

Ultra-small platinum nano-enzymatic spray with ROS scavenging and anti-inflammatory properties for photoaging treatment

Photoaging induced by ultraviolet (UV) results in oxidative stress and inflammation. Noble metal nanozymes have strong antioxidant and anti-inflammatory capacity, which are expected to eliminate the excessive reactive oxygen species (ROS) and inflammatory factors in the photoaged skin. Hence, we have synthesized ultrasmall platinum nanoparticles coated with polyvinylpyrrolidone (Pt NPs) with a diameter of nearly 5 nm for photoaging treatment. Thanks to multi-enzymatic capacities (catalase, peroxidase, and superoxide dismutase) of Pt NPs, they can effectively protect fibroblasts from UV-induced ROS attack, relieve fibroblasts from UV-induced cell cycle arrest, downregulate matrix metalloproteinases (MMPs) to regenerate type I collagen, and inhibit M1 macrophage polarization to decrease the expression of inflammatory factors. For photoaged mice treatment, we employ the concept of routine spray skincare and encapsulate Pt NPs solution in a spray bottle. In combination with roller needle, following Pt NPs nano-enzymatic spray given, UV-induced photoaged mice display reduced wrinkle formation in the collagen-depleted dermal tissue of mice and more youthful performance in both appearance and organizational structure. Consequently, multi-enzymatic functions of Pt NPs nano-spray offers a promising avenue for anti-photoaging therapy, providing potential benefits in both preventative and restorative skincare applications.

Therapeutic effects of focused ultrasound on vulvar squamous intraepithelial lesions in rat

Objective In this study, we established a Sprague-Dawley rat model of vulvar squamous intraepithelial lesions and investigated the impact of focused ultrasound on the expression of hypoxia-inducible factor-1α (HIF-1α), vascular endothelial growth factor (VEGF) and mutant type p53 (mtp53) in the vulvar skin of rats with low-grade squamous intraepithelial lesions (LSIL). Materials and methods The vulvar skin of 60 rats was treated with dimethylbenzanthracene (DMBA) and mechanical irritation three times a week for 14 weeks. Rats with LSIL were randomly allocated into the experimental group or the control group. The experimental group was treated with focused ultrasound, while the control group received sham treatment. Results After 14 weeks treatment of DMBA combined with mechanical irritation, LSIL were observed in 44 (73.33%) rats, and high-grade squamous intraepithelial lesions (HSIL) were observed in 14 (23.33%) rats. 90.91% (20/22) of rats showed normal pathology and 9.09% (2/22) of rats exhibited LSIL in the experimental group at four weeks after focused ultrasound treatment. 22.73% (5/22) of rats exhibited LSIL, 77.27% (17/22) of rats progressed to HSIL in the control group. Compared with the control-group rats, the levels of HIF-1α, VEGF and mtp53 were significantly decreased in experimental-group rats (p < 0.05). Conclusions These results indicate that DMBA combined with mechanical irritation can induce vulvar squamous intraepithelial lesion in SD rats. Focused ultrasound can treat LSIL safely and effectively, prevent the progression of vulvar lesions, and improve the microenvironment of vulvar tissues by decreasing the localized expression of HIF-1α, VEGF, and mtp53 in rats.

Combined mechanistic and machine learning method for construction of oil reservoir permeability map consistent with well test measurements

We introduce a novel method for estimating the spatial distribution of absolute permeability in oil reservoirs, consistent with well logging and well test measurements. The primary objective is to create a permeability map, incorporating the well test interpretation results and achieving hydrodynamic similarity to the actual permeability distribution around each well. This enhancement aims to improve the accuracy of reservoir modeling outcomes in reproducing real data. We utilize Nadaraya-Watson kernel regression to parameterize the two-dimensional spatial distribution of rock permeability. The kernel regression parameters are optimized by minimizing the discrepancies between actual and predicted values of permeability at well locations, the integral permeability of the reservoir domain around each well, and skin factors. This inverse optimization problem is addressed by repeatedly solving forward problems, where an artificial neural network (ANN) predicts the integral permeability of the formation surrounding a well and skin factor. The ANN is trained on a physics-based dataset generated through a synthetic well test procedure, which includes the numerical modeling of the bottomhole pressure decline curve in a reservoir simulator and its interpretation using a semi-analytical reservoir model. The proposed method is tested on the “Egg Model”, a synthetic reservoir with significant heterogeneity due to highly permeable channels. The permeability map created by our approach demonstrates hydrodynamic similarity to the original map. Numerical reservoir simulations, corresponding to the constructed and original permeability maps, yield comparable pore pressure and water saturation distributions at the end of the simulation period. Additionally, we observe a notable match in flow rates and total volumes of produced oil, water, and injected water between simulations. The developed approach outperforms kriging in terms of numerical reservoir modeling outcomes. This research advances existing geostatistical interpolation techniques by fusing well logging and well test data to build the reservoir permeability map through an optimization framework coupled with machine learning. Unlike traditional variogram-based geostatistical simulation algorithms, our method provides a permeability distribution that is hydrodynamically similar to the actual one, enhancing initial guess in the history matching process. The novel incorporation of well test interpretation results into the permeability map represents a significant improvement over existing methods, offering an innovative approach that can benefit the petroleum industry. We also provide recommendations for further development of the proposed algorithm to account for geological realism.

A Full-Stage Productivity Equation for Constant-Volume Gas Reservoirs and Its Application

Gas well production involves various stages, including stable, variable, and declining production. However, existing production-capacity equations typically apply only to the stable production stage, limiting their effectiveness in evaluating gas well productivity across all stages. To address this, the material balance equation and Darcy’s equation were employed to account for changes in average formation pressure due to pressure drop funnels. The concept of a pressure-conversion skin factor was introduced, and its approximation was developed, leading to the establishment and solution of a full-stage productivity equation. Numerical simulations were then conducted to verify the accuracy and applicability of this equation. The findings are as follows: ① The full-stage productivity equation remains effective even when production rates and pressure are not constant, with the only potential source of inaccuracy being the approximative solution for the pressure conversion-skin factor. ② Numerical simulations demonstrated that the approximate solution closely matched the numerical simulation results for average formation pressure across various production stages and fundamental parameters, showing a consistent trend and high precision. The approximate and independent approximation solutions for absolute open-flow capacity were nearly identical, indicating the full-stage productivity equation’s applicability throughout the production of gas wells. ③ Application results revealed that the full-stage productivity equation offers superior accuracy compared to the modified isochronous well test. ④ The approximate solution generally provides slightly higher accuracy, and the independent approximate solution effectively eliminates the influence of gas leakage radius. Therefore, the use of the approximate solution is recommended to calculate the average formation pressure and the independent approximate solution to calculate the absolute open-flow capacity. The full-stage productivity equation developed in this study is not constrained by the production system, making it suitable for productivity evaluation across all stages of gas well production. This has significant implications for the effective development of gas fields.

Skin Factor Test Experiment of the Combined Structure of Blind and Screen Pipes

During the drilling process of horizontal wells in offshore oil fields, when encountering highly clayey shale or sandy shale sections, a common practice is to use a combination of blank pipes and screen pipes in the completion column to isolate high clay content layers. This helps prevent significant clay blockage in the screen pipes or wellbore, thereby reducing production loss. However, when blank pipes cannot effectively isolate clayey or sandy shale sections, the migration of clay content can lead to screen pipe blockage, adversely affecting production capacity. Given the current lack of evaluation methods for the impact of combined blank and screen pipe completion columns on production capacity, an experiment was designed to evaluate the skin factor of the completion column with a combination of blank and screen pipes. Through the calculation of the skin factor, the variation patterns of the skin factor for completion columns with blank and screen pipes under different conditions were obtained. These findings were then applied to a production evaluation. The research results revealed the following: (1) As the proportion of blind pipes increases, the skin factor of the combination of blind pipes and screen pipes in the completion tubing also increases. Excessive blind pipe ratios reduce production capacity. (2) In cases where the annular space is not completely filled, the influence of the blind pipe proportion on production capacity can be negligible. However, when the annular space is 100% filled, a higher proportion of blind pipes and silt content results in a larger skin factor, which leads to reduced production. In the application of the XH horizontal well case study, using the calculated model for the skin factor of the combination of blind pipes and screen pipes in the completion tubing established in this paper, it was determined that when the annular space was not completely blocked and 20 m of blind pipes were not placed in the designated position, the impact on the production index was 0.73%. However, when the blind pipes were not placed in the designated position for 100 m, the impact on the production index reached 1.47%. The method developed in this paper provides theoretical guidance for the optimization of completion tubing in mudstone and sandy mudstone sections and for production evaluation.

SIMPLIFIED COMPUTATIONAL TOOL FOR PREDICTING FORMATION DAMAGE IN OIL WELLS

The present study underscores the significance of regular well test analysis to ensure the accuracy and consistency of data pertaining to the permeability and skin of exploratory wells. This study advances the development of a novel computer model, ASPIRE, which predicts formation damage in oil wells by analysing well-test data. In this context, identifying blocked pore throats in the formation close to the wellbore by paraffinic deposits (scales) and its influence on permeability necessitates routine well-test analysis. The software employs a modified linear regression model developed in this study to perfectly fit the well-test data's infinitely acting linear flow (IARF) region to a straight line. The cases "CASE 1" and "CASE 2" were considered for constant rate transient drawdown well test analyses. The findings indicate that Case 1, with a high skin factor, requires remedial action, such as stimulation, to increase the formation's permeability close to the wellbore for enhanced productivity. In contrast, Case 2 has higher permeability and lower skin factor than Case 1, so stimulation is not required. In addition, R-squared analyses were conducted to validate the results obtained from the developed tool. The analyses reveal an R-square value of 1 for all cases, indicating a 100% accuracy. Therefore, the study concludes that the developed tool is instrumental in accurately predicting formation damage in oil wells.

Geomechanics Modeling of Strain-Based Pressure Estimates: Insights from Distributed Fiber Optic Strain Measurements

Summary Rayleigh frequency shift distributed strain sensing (RFS-DSS) has been demonstrated as a potential technology for characterizing fracture geometries and optimizing the completion design in unconventional reservoirs. The combination of RFS-DSS strain and pressure gauge measurements has been reported recently in field applications (Dhuldhoya and Friehauf 2022; Haustveit and Haffener 2023) to characterize conductive fracture dimensions and production profiles. Haustveit and Haffener (2023) demonstrated a novel technique that uses RFS-DSS strain change during production, measured from a far-field observation well, to monitor the drain profile of a horizontal multistage well. The strain change and pressure change were strongly related during production, and this relationship was applied to continuously estimate pressure drawdown along the full length of the well. However, the sensitivity or influencing factors of the relationship between strain change and pressure change along the fiber are not yet fully understood. Therefore, the main objective of this study is to investigate the relationship between strain change and pressure change under various fractured reservoir conditions and provide guidelines for better utilizing this novel strain-pressure relationship to estimate conductive fractures and pressure profiles. We use a coupled geomechanics and fluid flow model to simulate the strain and pressure changes in the near-well and far-field regions during stable production and shut-in periods. A linear relationship is used to fit the strain change and pressure change data obtained from both producing and monitoring wells. We analyze the impact of various fracture properties [size and permeability of the stimulated reservoir volume (SRV) around fractures, fracture conductivity, fracture area, and skin factor] on the linear relationship based on the R2 value and fitting error. The relationship between the strain change and pressure change during the stable production obtained by our numerical study is consistent with the field measurements. The slope of strain change vs. pressure change during one day of production is significantly influenced by fracture properties. Overall, the monitoring well shows a stronger linear relationship than the producing well during both stable production and shut-in periods. A better linear relationship between the strain change and pressure change is associated with a larger fracture conductivity or larger fracture spacing scenario on both producing and monitoring wells during the stable production period. The cluster spacing affects the linear relationship between strain and pressure change during rock deformation. When cluster spacing is reduced, the nonlocal effect of deformation becomes more pronounced, resulting in a weaker linear relationship. During the shut-in period, the monitoring well exhibits a stronger linear relationship with a high R2 value and small fitting error compared to the producing well. The linear relationship obtained during the shut-in period is less reliable for the producing well. In cases of homogeneous fractures, where the fracture properties are uniform, the strain change and pressure change are similar, except for two outer fractures. This study provides a better understanding of the relationship between strain change and pressure change measured in the near-well and far-field regions during stable production and shut-in periods. The results of our study also demonstrate the potential for utilizing the RFS-DSS strain measurement to characterize the effective fracture and drainage dimensions.

Neurturin GF Enhances the Acute Cytokine Response of Inflamed Skin

Epidermal keratinocytes, immune cells and sensory nerves all contribute to immune balance and skin homeostasis. Keratinocyte release of growth factors, neuromodulators and immune activators is particularly important because each can evoke local (skin) and systemic (i.e., immune and neural) responses that can initiate and exacerbate skin pathophysiology. From studies of skin and neural growth factors, we hypothesized that neurturin (Nrtn), a member of the glial cell line-derived neurotrophic factor (GDNF) family that is expressed in skin, has particular importance in this process. Here we examine how elevation of Nrtn in skin keratinocytes impacts early cytokine expression in response to complete Freund's adjuvant (CFA)-mediated inflammation. Mice that overexpress Nrtn in keratinocytes (NrtnOE mice) and WT mice injected with Nrtn exhibit an enhanced level of TNFα and IL-1β cytokines in the skin, a response previously shown to support healing. In vitro assays suggest one source of the Nrtn-induced TNFα increase is from keratinocytes, which are shown to express Nrtn and mRNAs encoding the Nrtn receptors GFRα2, Ret, Itgβ1 and NCAM. These findings support the contribution of keratinocyte-derived Nrtn as an autocrine/paracrine factor that acts as a first line defense molecule that regulates the initial cytokine response to inflammatory challenge.

Analysis of Skin Disorders Among Traditional Fishermen in Tanjung Balai, Asahan District

&lt;div&gt;&lt;table cellspacing="0" cellpadding="0" align="left"&gt;&lt;tbody&gt;&lt;tr&gt;&lt;td align="left" valign="top"&gt;&lt;p&gt;&lt;em&gt;Skin disorders are diseases often found in the community caused by fungi, bacteria, viruses, and marine life characterized by rashes, itching, and others. Traditional fishermen are a group of people at high risk of skin disorders due to exposure to seawater, unhygienic working environment conditions, incomplete behaviour of using fishermen's protective equipment when working and personal hygiene behaviour classified as harmful. This study aims to analyze skin disorders among traditional fishermen in Tanjung Balai, Asahan District. The research employs a quantitative, analytical survey with a cross-sectional design. The study was conducted in Tanjung Balai, Asahan District, from August 2023 to March 2024. The research population consisted of all traditional fishermen, totalling 110, 110 traditional fishermen, with the sample taken based on the total population of 110 fishermen in Tanjung Balai, Asahan District. The sampling technique used was total sampling. Data collection was conducted using using questionnaires that have been tested for validity, reliability, and observation. Data analysis involved two steps: univariate analysis using descriptive statistics and frequencies and bivariate analysis using the chi-square test with a significance level of 95% (p-value ≤ 0.05). The statistical analysis results indicated significant associations between skin disorders and factors such as duration of work (p=0.001), use of personal protective equipment (p=0.038), and fishermen's hygiene (p=0.014). It is recommended that traditional fishermen use complete personal protective equipment and maintain better personal hygiene after working to prevent the occurrence of skin disorders.&lt;/em&gt;&lt;/p&gt;&lt;p&gt;&lt;em&gt; &lt;/em&gt;&lt;/p&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/tbody&gt;&lt;/table&gt;&lt;/div&gt;&lt;p&gt;&lt;strong&gt;&lt;em&gt;Keywords: Skin disorders, traditional fishermen&lt;/em&gt;&lt;/strong&gt;&lt;/p&gt;

Local keratinocyte-nociceptor interactions enhance obesity-mediated small fiber neuropathy via NGF-TrkA-PI3K signaling axis.

The pathology of diabetic small fiber neuropathy, characterized by neuropathic pain and axon degeneration, develops locally within the skin during the stages of obesity and pre-diabetes. However, the initiation and progression of morphological and functional abnormalities in skin sensory nerves remains elusive. To address this, we utilized ear skin from mice with diet-induced obesity (DIO), the mouse models for obesity and pre-type 2 diabetes. We evaluated pain-associated wiping behavior and conducted ex vivo live Ca2+ imaging of the DIO ear skin to detect sensory hypersensitivity. Our findings reveal sensory hypersensitivity in skin nociceptive axons followed by axon degeneration. Further mechanistic analysis identified keratinocytes as a major source of nerve growth factor (NGF) in DIO skin, which locally sensitizes nociceptors through NGF-mediated signaling. Indeed, the local inactivation of NGF and its receptor TrkA-mediated downstream signaling, including the phosphoinositide 3-kinases (PI3K) pathway, suppresses sensory hypersensitivity in DIO skin. Thus, targeting these local interactions between keratinocytes and nociceptors offers a therapeutic strategy for managing neuropathic pain, avoiding the adverse effects associated with systemic interventions.

A Two-Phase Flowback Type Curve with Fracture Damage Effects for Hydraulically Fractured Reservoirs

Summary Type curves are a powerful tool in characterizing hydraulic fracture (HF) and reservoir properties based on flowback and production data. We propose a type-curve method to evaluate HF characteristics and their dynamics for multifractured horizontal wells (MFHWs) in hydrocarbon reservoirs using flowback production data. The type curve incorporates the HF damage effect of choked-fracture skin factor in the two-phase flow in HF and matrix domains. The type-curve method can be applied to inversely estimate choked-fracture skin factor, s, HF pore volume (PV), Vfi, and HF initial permeability, kfi, by analyzing two-phase flowback production data. By introducing the new dimensionless parameters, the nonuniqueness problem of the type-curve analysis for two-phase flow is significantly reduced by incorporating the complexity of fracture dynamics into one set of curves. The accuracy of the type curve is examined against the results obtained from numerical simulations of shale gas and oil reservoirs. The validation results demonstrate a good match of analytical type curves and numerical data plots and confirm the accuracy of the proposed method in estimating the static and dynamic fracture properties. The results show that the relative errors in Vfi, kfi, and s estimations are all &amp;lt;10% for the simulated cases that are presented in this work. The flexibility and robustness of the proposed method are illustrated using the field example from a shale oil MFHW. The accuracy and applicability of the proposed type curve are also validated by comparing the calculated fracture properties from the field example using straightline analysis with Vfi and kfi of 705.3 Mcf and 245.2 md, type-curve analysis method (without skin effect) with Vfi and kfi of 751.9 Mcf and 249.8 md, and the type-curve method (with the choked fracture skin considered) with Vfi and kfi of 708.7 Mcf and 252.9 md, which showed that the results of each case are very close to one another. The interpreted results from the flowback analysis of the field example offer quantitative insight into HF properties and dynamics.

Development of a Risk Prediction Model for Adverse Skin Events Associated with TNF-α Inhibitors in Rheumatoid Arthritis Patients.

Background: Rheumatoid arthritis (RA) is a chronic inflammatory disorder primarily targeting joints, significantly impacting patients' quality of life. The introduction of tumor necrosis factor-alpha (TNF-α) inhibitors has markedly improved RA management by reducing inflammation. However, these medications are associated with adverse skin reactions, which can vary greatly among patients due to genetic differences. Objectives: This study aimed to identify risk factors associated with skin adverse events by TNF-α in RA patients. Methods: A cohort study was conducted, encompassing patients with RA who were prescribed TNF-α inhibitors. This study utilized machine learning algorithms to analyze genetic data and identify markers associated with skin-related adverse events. Various machine learning algorithms were employed to predict skin and subcutaneous tissue-related outcomes, leading to the development of a risk-scoring system. Multivariable logistic regression analysis identified independent risk factors for skin and subcutaneous tissue-related complications. Results: After adjusting for covariates, individuals with the TT genotype of rs12551103, A allele carriers of rs13265933, and C allele carriers of rs73210737 exhibited approximately 20-, 14-, and 10-fold higher incidences of skin adverse events, respectively, compared to those with the C allele, GG genotype, and TT genotype. The machine learning algorithms used for risk prediction showed excellent performance. The risk of skin adverse events among patients receiving TNF-α inhibitors varied based on the risk score: 0 points, 0.6%; 2 points, 3.6%; 3 points, 8.5%; 4 points, 18.9%; 5 points, 36.7%; 6 points, 59.2%; 8 points, 90.0%; 9 points, 95.7%; and 10 points, 98.2%. Conclusions: These findings, emerging from this preliminary study, lay the groundwork for personalized intervention strategies to prevent TNF-α inhibitor-associated skin adverse events. This approach has the potential to improve patient outcomes by minimizing the risk of adverse effects while optimizing therapeutic efficacy.

Evaluation of near wellbore damaged conditions with an injection - falloff tests during transient flow regime in clastic hydrocarbon reservoir

Low or near zero daily oil production from a well below its potential is undesirable and should be addressed. This problem is caused by permeability reduction or impairments in the vicinity of a wellbore and could be due to one or combinations of the following factors; mud filtrate invasion, fines redeposition due to production, microbial growth, fracturing fluid, and enhanced chemical processes. The extent of this problem has to be quantitatively evaluated, using a skin factor, before an appropriate solution can be developed. A set of secondary data was simulated with a commercial software package, for a reservoir undergoing transient flow condition acting infinitely. A water injection well, fully perforated, is placed at the centre of an infinite-acting reservoir, for constant water injection. The wellbore radius of 0.5 ft fully penetrated the entire length of 190 ft, and injected water at 250 bbls per day, with water viscosities of 0.8 cP to 1.2 cP, continuously for 4 days. Water injection pressure stabilized at 1300 psi. Analysis of both injectivity and falloff were performed with an initial assumption of zero wellbore storage effects to evaluate formation permeability and skin factor, S. The result showed that skin factor increases with decreasing water viscosities. At water viscosity of 0.8 cP to 1.2 cP, a constant value of skin factor was obtained. An S value of +0.09 indicated that the near wellbore environment is slightly damaged. Therefore, it requires light acidization.

Qingxiong Ointment and its Active Ingredient, Shikonin Treat Psoriasis through HIF-1 Signaling Pathway.

Psoriasis is a common chronic inflammatory skin disorder. Qingxiong ointment (QX) is a natural medicinal combination frequently employed in clinical treatment of psoriasis. However, the active ingredients of QX and its precise mechanisms of improving psoriasis remain unclear. This study elucidated the effects of QX on an Imiquimod (IMQ)-induced mouse model of psoriasis while also exploring the regulation of the active ingredient of QX, shikonin, on the HIF-1 signaling pathway in HaCaT cells. A mouse model of psoriasis was established through topical application of IMQ, and the local therapeutic effect of QX was evaluated using dorsal skin tissue with mouse psoriatic lesion and Psoriasis Area Severity Index (PASI) scores, hematoxylin-eosin (HE) staining, and immunohistochemical staining. Elisa and qPCR were employed to identify changes in the expression of inflammation-related factors in the mouse dorsal skin. Immunofluorescence was used to assess changes in the expression of T cell subsets before and after treatment with various doses of QX. HPLC was used to analyze the content of shikonin, and network pharmacology was employed to analyze the main targets of shikonin. Immunofluorescence was used to identify the effects of shikonin on the HIF-1 signaling pathway in IL6-induced psoriasis HaCaT cells. Finally, qPCR was used to identify the differential expression of the HIF-1 signaling pathway in skin tissues. QX significantly reduces PASI scores on the backs of IMQ-induced psoriasis mice. HE staining reveals alleviated epidermal thickness in the QX group. Immunohistochemical analysis shows a significant reduction in ICAM, KI67, and IL17 expression levels in the QX group. Immunofluorescence results indicate that QX can notably decrease the proportions of CD4+ T cells, γδ T cells, and CD8+ T cells while increasing the proportion of Treg cells. Network pharmacology analysis demonstrates that the main targets of shikonin are concentrated in the HIF-1 signaling pathway. Molecular docking results show favorable binding affinity between shikonin and key genes of the HIF-1 signaling pathway. Immunofluorescence results reveal that shikonin significantly reduces p-STAT3, SLC2A1, HIF1α, and NOS2 expression levels. qPCR results show significant downregulation of the HIF-1 signaling pathway at cellular and tissue levels. Our study revealed that QX can significantly reduce the dorsal inflammatory response in the IMQ-induced psoriasis mouse model. Furthermore, we discovered that its main component, shikonin, exerts its therapeutic effect by diminishing the HIF-1 signaling pathway in HaCaT cells.

Pressure Transient and Production Analysis of Fractured Vertical Wells in Tight Sand Gas Reservoirs Considering Threshold Pressure Gradient, Phase-Change Phenomenon, and Stress Sensitivity

The productivity and pressure response of the tight sand gas wells are influenced by multiple flow mechanisms, such as threshold pressure gradient, phase-change phenomena, and stress sensitivity. Understanding the sensitivity of these factors is crucial for the effective development of tight sand gas reservoirs. This study aims to clarify the sensitivity of various factors affecting the productivity and pressure response of tight sand gas wells. Based on the percolation theory of tight sand gas reservoirs, we considered stress sensitivity, threshold pressure gradient, and phase-change phenomena to derive an unsteady mathematical model of a fractured well with an infinite boundary, and a point source solution was obtained. The proposed model was solved using series function properties, variable substitution, perturbation technique, Poisson superposition formula, Laplace transform, and numerical inversion. The influence of several important parameters on pressure response and productivity is discussed in detail. The results show that the threshold pressure gradient, stress sensitivity, and skin factor significantly impact gas well production and pressure response, while the wellbore storage effect and phase-change effect primarily affect the initial production and pressure response, having little effect on the cumulative gas production. The proposed model can estimate the influence of the threshold pressure gradient and stress sensitivity on productivity and pressure, providing a guide for the development of technical measures for fractured wells in tight sand gas reservoirs.

CD4+ T-cell Subsets and Cytokine Signature in Pemphigus Foliaceus Clinical Stratification beyond the th1/Th2 Paradigm.

T helper interplay and cytokines monitoring in auto-immune skin disorders such as Pemphigus Foliaceus [PF] may play a central role in predicting the clinical stratification of the pathology. In order to assess the CD4+ T cell imbalance, [i] this study aims to assess the related immune cells [Th1, Th2, Th17, and Treg cells] as well as the related cytokines [IL-1β, IFNγ, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12p70, IL-17A, IL-17F, IL- 22, TNF-β, and TNFα] in peripheral blood, and [ii] their respective transcription factors in the lesioned skin of PF endemic patients during the clinical course. Peripheral blood of 22 PF patients was analyzed by flow cytometry to assess the functional associations of Th cell subpopulations and their characteristic cytokines by multiplex bead assay of 14-plex cytokines. Skin mRNA expression of their associated transcription factors was analyzed using the TaqMan detection system. Our findings revealed that the CD4+ T cell subtypes in PF patients compared to Healthy Controls [HC] were characterized by [i] a similar Th1/Th2 ratio and increased Th17/Treg ratio and [ii] significantly higher plasma levels of Th-17 specific cytokines; IL- 6, IL-8, IL-17A. Higher percentages in Th17 and Treg subtypes and a significant increase in plasma IL-17F levels were maintained in relapsing PF patients, arguing the pivotal role of Th17 cells in PF pathogenesis. Furthermore, our findings pointed out the major contribution of the pro-inflammatory cytokine IL-6. Indeed, in addition to being involved in the initial stages of disease development, IL-6 seems to also be involved in the maintenance of the pathophysiological process, probably through its effect on Th17 differentiation. The skin-relative mRNA expression levels of FOXP3 and TBET were significantly higher in relapsing PF patients compared to de novo PF patients. Our results highlight the central role played by Th17 lymphocytes and their related pro-inflammatory cytokines during the clinical course of the disease, reversing the Th1/Th2 dichotomy in PF.

Model-based interpretation of bottomhole pressure records during matrix treatments in layered formations

During injection treatments, bottomhole pressure measurements may significantly mismatch modeling results. We devise a computationally effective technique for interpretation of fluid injection in a wellbore interval with multiple geological layers based on the bottomhole pressure measurements. The permeability, porosity and compressibility in each layer are initially setup, while the skin factor and partitioning of injected fluids among the zones during the injection are found as a solution of the problem. The problem takes into account Darcy flow and chemical interactions between the injected acids, diverter fluids and reservoir rock typical in modern matrix acidizing treatments. Using the synchronously recorded injection rate and bottomhole pressure, we evaluate skin factor changes in each layer and actual fluid placement into the reservoir during different pumping jobs: matrix acidizing, water control, sand control, scale squeezes and water flooding. The model is validated by comparison with a simulator used in industry. It gives opportunity to estimate efficiency of a matrix treatment job, role of every injection stage, and control fluid delivery to each layer in real time. The presented interpretation technique significantly improves accuracy of matrix treatments analysis by coupling the hydrodynamic model with records of pressure and injection rate during the treatment.

INFLUENCE OF SKIN FACTOR VALUES ON WELL PRODUCTIVITY

For several decades, the problem of increasing oil recovery from reservoirs has been one of the most significant in oil-producing countries of the world. Most oil fields, usually represented by heterogeneous reservoirs, are developed using a waterflooding system. Experience in the development of water-oil zones shows that oil extraction from deposits underlain by bottom water is characterized by a relatively low oil recovery factor. When monitoring the development of oil and gas fields, various research methods are used. One of the main research methods is hydrodynamic testing of wells (HDT). The article discusses the influence of the skin factor on well productivity. Keywords: skin factor, productivity coefficient, mobility, water cut.