bluuebunny/crossref_metadata_2025 huggingface dataset:
Simulations of Alkali-Polymer Experiments: Modeling of In-Situ Emulsion Generation and Transport of Oil-In-Water Emulsion in Porous Media
Authors: Perez-Perez Alfredo , Romero Carolina , Santanach-Carreras Enric , Skauge Arne
Published: June 2023

The injection of alkali in acidic viscous oils is known to promote the in-situ formation of emulsions during chemical oil recovery. Naphthenic acid components react with the alkali to form in-situ surfactants, which support oil emulsification at the water-oil interface. It is believed that emulsification and transport of the dispersed oil in the presence of polymer can significantly improve oil recovery.

In earlier work, we proposed a new mechanistic non-equilibrium model to simulate alkali-polymer processes for different oil viscosities (2000 – 3500 cP at 50°C) with an acid number of around 4 mg KOH/g. The model considers emulsion generation kinetics, polymer, and emulsion non-Newtonian viscosity through a straightforward modelling strategy. The emulsified oil was treated as a dispersed component in water phase (O/W emulsion), while the water phase mobility considered the apparent aqueous phase viscosity containing dispersed oil and polymer.

In the above referenced work, seven alkali-polymer corefloods performed with different alkali types and slug sizes were history matched. We showed that the model is capable of appropriately matching the experiments. Kinetics obtained by history match show that emulsion formation under the conditions here studied is alkali type dependent.

In the current work, we applied our alkali-polymer model in two displacement tests (Hele Shaw cell) with two different oil viscosities (2000 – 200 cP at 50°C). These new experiments included secondary water flood, tertiary polymer flood and quaternary alkali-polymer flood. The initial conditions of alkali-polymer (AP) flood were obtained after properly modelling the unstable immiscible floods and polymer floods. For modelling the polymer floods (2D slabs), three models were evaluated: 1) extension of relative permeability curves applied to water flood, 2) Killough method (hysteresis for the water phase) and relative permeability power-law extensions and 3) two relative permeability curves with polymer concentration dependency.

Our alkali-polymer model was employed for simultaneously history matching 1D and 2D experiments performed with 5 g/L of Na2CO3 and polymer. When comparing alkali-polymer results, a good agreement was found for the complete set of experiments. In addition, fitting parameters (kinetics and emulsion viscosity) were close to the parameters reported in the earlier study.

Finally, fitted alkali-polymer parameters were employed for predicting alkali-polymer outputs in the second slab (with similar alkali-polymer concentration but lower oil viscosity). Even if experimental observations are relatively well represented, a lower value of incremental oil recovery (<3 % OOIP) was obtained. We believe that the use of a less viscous oil (diluted oil) in the experiments may influence the generation and transport of formed emulsions.
Simulation and Prediction of Countercurrent Spontaneous Imbibition at Early and Late Times Using Physics-Informed Neural Networks
Authors: Abbasi Jassem - , Andersen Pål Østebø
Published: June 2023

We investigated countercurrent spontaneous imbibition (COUCSI) of water displacing oil in a 1D linear system with one side open, and one side closed. The Physics-Informed Neural Networks (PINNs) technique was used to estimate saturation profiles along the core and recovery against time; based on the same input information as a reservoir simulator. We demonstrate the usefulness of Change-of-Variables as an approach to improve PINN solutions.

The problem was first normalized, where only a saturation-dependent diffusion coefficient results in different solutions. The initial condition was zero saturation, the open boundary had a saturation equal to one, and the closed boundary had a zero saturation gradient. We formulated the problem in three equivalent ways by Change-of-Variables: XT, YZ, and Z formulations. The first is the original normalized form and describes saturation as a function of normalized position X and time T. The second defines saturation as a function of Z=X/T^0.5 and Y=T^0.5. The third considers saturation as a sole function of Z=X/T^0.5 and is valid only at early times (ET), before water meets the no-flow boundary. The COUCSI problem was solved using a feed-forward neural network trained based on a weighted loss, including the physics-informed loss term and terms corresponding to initial and boundary conditions for all the formulations. No synthetical or experimental data were involved in the training. The generalization ability is tested by applying the workflow to two imbibition cases with different displacement profile behavior. The PINN solutions were tracked to determine if they followed the flow's theoretical properties, including self-similarity, square root of time behavior, and Total Variation (TV). We investigated the ability of the applied formulations to estimate the correct solution (compared to numerical simulations) at early and late times.

All the formulations could very closely converge to the correct solutions, with the water saturation mean absolute errors around 3.5 and 2.5 percent for XT and YZ formulations and 1.0 percent for the Z formulation at ET. The Z formulation almost perfectly captured the self-similarity properties of the system in the ET period (and in lower level, YZ), which only depends on X/T^0.5 at early time. The TV of saturation was successfully preserved in the Z formulation and YZ performed better than XT formulation. By performing a sensitivity analysis we demonstrate that Change-of-Variables can lead to a lower number of required collocation points and also smaller network sizes.
Fluid Identification from Mud Gas in the Overburden – A Case Study for the Snorre Field
Authors: Ungar Frode , McGill Andrew , Nygaard Marianne Therese , Dos Reis Teo Paiva , Kvilhaug Sigurd , Wagner Vincent , Yang Tao
Published: June 2023

Based on the successful utilization of advanced mud gas (AMG) for fluid identification in five production/injection wells in the Snorre field, the fluid identification while drilling technology was deployed for a seismic anomaly within the overburden at the Kyrre formation level. The main objective was to identify the reservoir fluid type (oil versus gas) within the anomaly and to use this information to potentially de-risk a similar shallower seismic anomaly - the Linga prospect at the top Shetland level.

Fluid identification while drilling is an award-winning innovation that has been broadly used in exploration and production wells at Equinor. The digital technology combines mud gas and PVT data for accurate reservoir fluid typing and property predictions. Snorre field is one of the first users of the technology and accumulated good experiences regarding the capacity and limitations in reservoir zones. Due to the lack of other good tools to identify the hydrocarbon in overburden in a cost-efficient manner, the Snorre field decided to deploy the fluid identification technology for the task.

Utilizing AMG data in the overburden for the four Snorre Expansion Project (SEP) wells showed satisfactory results. Reservoir oil was identified with confidence in the Kyrre formation for the first three wells, and no additional logging was necessary. The 4th well was drilled with higher ROP (above 30 m/hr) and proved a similar oil signature without compromising the data quality. The main objective was met, the fluid type in the Kyrre anomaly was confirmed, and this result was a de-risked Linga prospect. The probability of producing the Linga prospect has increased due to the accurate reservoir fluid type.

The experiences in the overburden from the Snorre field show fluid identification from mud gas is a cost-efficient tool and has the potential to be utilized broadly in the overburden. With an accurate fluid identification in the overburden, we can achieve safety assurance, reduced drilling costs, and matured production prospects.
Auto-Correction Algorithm of Multiphase Flowmeter Water Cut Measurements in Undersaturated Oil Wells
Authors: Alali Mohammed H.
Published: June 2023

Dual energy gamma ray attenuation in multiphase flow meters (MPFMs) are commonly used in the oil and gas industry to measure the flow rate of hydrocarbon producing wells. The low energy gamma ray attenuation is highly dependent on water salinity, making this type of MPFM very sensitive to water salinity. This challenge is evident in oil fields where lower salinity water is injected into the reservoir to maintain pressure for oil producing wells, imposing changes in water salinity with time. Hence, frequent fluid sampling and calibration is required to ensure high reliability measurements from such meters. In this paper, a new methodology is proposed to automatically correct the deviation in MPFM water cut measurements due to water salinity changes without the need to collect fluid samples.

The methodology proposed in this paper is a gas-oil ratio (GOR) based method that corrects the deviation in MPFM measurements due to the change in water salinity without the need to collect any fluid sample. In addition, the method does not require any additional information to be acquired from any other sources, other than the normal parameters acquired by the MPFM. The method is applicable to oil wells producing from undersaturated reservoirs. Furthermore, for the method to be reliable, the operating condition at the MPFM has to have adequate amount of free gas because the methodology is GOR based methodology.

The results from the proposed method were cross checked against data collected from multiphase separator tests and showed excellent agreement. It was also tested across multiple undersaturated oil reservoirs against a wide range of oil properties and water salinities.

The method will help identify the MPFM that require calibration and will eventually make MPFM measurements more reliable without the need for frequent fluid sampling for meter calibration. This method will also lead to reducing the need for rigless multiphase separator testing requirements resulting in substantial cost reduction.
Measurement of Effective Hydrogen-Hydrocarbon Gas Diffusion Coefficients in Reservoir Rocks
Authors: Arekhov Vladislav , Zhainakov Timur , Clemens Torsten , Wegner Jonas
Published: June 2023

If hydrogen is stored in depleted gas fields, the remaining hydrocarbon gas can be used as cushion gas. The composition of the back-produced gas depends on the magnitude of mixing between the hydrocarbon gas and the hydrogen injected. One important parameter that contributes to this process of mixing is molecular diffusion. Although diffusion models are incorporated in latest commercial reservoir simulators, effective diffusion coefficients for specific rock types, pressures, temperatures, and gas compositions are not available in literature. Thus, laboratory measurements were performed to improve storage performance predictions for an Underground Hydrogen Storage (UHS) project in Austria.

A high-pressure-high-temperature experimental setup was developed that enables measurements of effective multicomponent gas diffusion coefficients. Gas concentrations are detected using infrared light spectroscopy, which eliminates the necessity of gas sampling. To test the accuracy of the apparatus, binary diffusion coefficients were determined using different gases and at multiple pressures and temperatures. Effective diffusion coefficients were then determined for different rock types. Experiments were performed multiple times for quality control and to test reproducibility.

The measured binary diffusion coefficients without porous media show a very good agreement with the published literature data and available correlations based on the kinetic gas theory (Chapman-Enskog, Fuller-Schettler-Giddings). Measurements of effective diffusion coefficients were performed for three different rock types that represent various facies in a UHS project in Austria.

A correlation between static rock properties and effective diffusion coefficients was established and used as input to improve the numerical model of the UHS. This input is crucial for the simulation of back-produced gas composition and properties which are essential parameters for storage economics. In addition, the results show the impact of pressure on effective diffusion coefficients which impacts UHS performance
P/Z for CO2 Injection into Depleted Gas Reservoirs
Authors: de Kok Joop Hendrik , Huijskes Thijs Diederik
Published: June 2023

Pressure data can be used to identify possible leaks in a CO2 storage site. However, conventional diagnostic plots used during gas production cannot directly be used to interpret the data, because CO2 properties have a different pressure dependency compared to the hydrocarbon gas initially in place. This paper investigates the possibility of adjusting p/Z plots for CO2 storage into depleted gas reservoirs to make them suitable for monitoring during injection.

The p/Z method is explained analytically for both gas production and CO2 injection. A method is proposed to graphically ensure that the p/Z plot during injection overlies the p/Z plot during depletion – the injection line follows the p/Z plot backwards. The method proposes to use a volume-weighted Z-factor to scale both p/Z and injected volume. This method is verified with compositional thermal simulations in a homogeneous model.

The uncertainty of both pressure and Z-factor is investigated and the implications of these uncertainties are discussed. Additionally, the proposed method is tested for reservoirs that do not show volumetric depletion behavior.

For a volumetric gas reservoir (straight-line p/Z) without near-wellbore cooling it is possible to follow the original p/Z plot backwards with the proposed method. Cooling of the near-wellbore area causes a temperature induced increase of density. The impact of this phenomenon is less than 4% on the p/Z estimate in the described case. With an analytical estimate of the extent of the cooling area, the p/Z value can be corrected to an error of less than 1.5%.

Uncertainty in Z for natural gas and CO2 at reservoir conditions can be significant, but generally result in a low impact on the accuracy of the method. The uncertainty in static pressure is larger with CO2 injection due to the higher fluid viscosity and more uncertain downhole density.

For reservoirs with ‘slow gas’ behavior, the proposed method does not result in an overlap with the depletion p/Z plot. However, the method does reproduce the path that methane injection follows.

The proposed methodology indicates to what extent the storage is filled and has the potential to identify large leakage of CO2 (>1% of GIIP) for volumetric gas reservoirs. To verify the observed potential leak, it is recommended to perform full field simulation.
Modeling hydrological responses of watershed under climate change scenarios using machine learning techniques
Authors: Karimizadeh Keivan , Yi Jaeeung
Published: June 2023

Climate change is the most important problem of the earth in the current century. In this study, the effects of climate change on precipitation, temperature, wind speed, relative humidity and surface runoff in Saghez watershed in Iran investigated. The main methods were using the Coupled Model Intercomparison Project phase 6 (CMIP6), the Soil and Water Assessment Tool (SWAT) and the Artificial Neural Network (ANN) model under the Shared Socio-economic Pathway scenarios (SSPs) using the Linear Scaling Bias Correction (LSBC) for the future period (2021–2050) compared to the base period (1985–2014). MAE, MSE, RMSE and R2 indices used for model calibration and validation. The results of forecasting temperature, precipitation, wind speed and relative humidity showed the average percentage of precipitation decrease in the future period will be 6.1%. In terms of the temperature, 1.4, 1.5 and 1.6 Cº increase predicted for minimum, average and maximum temperatures, respectively. The results of studying the surface runoff changes using the SWAT model also illustrated that based on all three scenarios SSP1-2.6, SSP3-7.0 and SSP5-8.5 in the future period, the amount of surface runoff will decrease, which based on three mentioned scenarios is equals to 17.5%, 23.7% and 26.3% decrease, respectively. Furthermore, the assessment using the artificial neural network (ANN) also showed that the parameters of precipitation in the previous two days, wind speed and maximum relative humidity have the greatest effect on the watershed runoff.
Shannon Entropy of Performance Metrics to Choose the Best Novel Hybrid Algorithm to Predict Groundwater Level (Case study: Tabriz plain, Iran)
Authors: Saroughi Mohsen , Achite Mohammed , Mirzania Ehsan , Katipoğlu Okan Mert , Ehteram Mohammad
Published: June 2023

Predicting groundwater level (GWL) fluctuations, which act as a reserve water reservoir, Particularly in arid and semi-arid climates, is vital in water resources management and planning. Within the scope of current research, a novel hybrid algorithm is proposed for estimating GWL values in the Tabriz plain of Iran by combining the artificial neural network (ANN) algorithm with newly developed nature-inspired Coot and Honey Badger metaheuristic optimization algorithms. Various combinations of meteorological data such as temperature, evaporation and precipitation, previous GWL values, and the month and year values of the data were used to evaluate the algorithm's success. Furthermore, shannon entropy of performance of models was assessed according to 44 different statistical indicators which is classified into two class: accuracy and error class. Hence, based on high value of Shannon entropy, the best statistical indicator was selected and the results of best model and selecting the best scenario were analyzed. Results indicated that value of Shannon entropy is higher for accuracy class than error class. Also, for accuracy and error class respectively, Akaikes Information Criterion (AIC) and Residual Sum of Squares (RSS) indexes with the highest entropy value which is equal to 12.72 and 7.3 are the best indicators of both classes and Legate-McCabe Efficiency (LME) and Normalized Root Mean Square Error-mean (NRMSE-Mean) indexes with the lowest entropy value which is equal to 3.7 and -8.3 are the worst indicators of both classes. According to the results of evaluation best indicator in the testing phase, AIC indicator value for HBA-ANN, COOT-ANN, and the stand-alone ANN models is equal to -344, -332.8, -175.8, respectively. Furthermore, it was revealed that the proposed metaheuristic algorithms significantly ameliorate the performance of the stand-alone ANN model and offered satisfactory GWL prediction results.
Finally, it was concluded that the Honey Badger optimization algorithm showed superior results than the Coot optimization algorithm in GWL prediction.
The change of diabetic macular edema post vitrectomy in patients with proliferative diabetic retinopathy
Authors: Zhou Han tao , Mei Jing hao , Lin Ke , Deng Chu ying , Lin Wei , Lin Zu shun , Lin Jue , wu ronghan , lin zhong
Published: June 2023

Purpose To investigate the change of diabetic macular edema (DME) post vitrectomy and its risk factors.Methods Retrospective study design. This study included 365 eyes of 330 patients who underwent vitrectomy for proliferative diabetic retinopathy with gradable optical coherence tomography imaging from January 2018 to March 2022. The incidence of post vitrectomy DME (PV-DME) was defined as patients with a central retinal thickness (CRT) > 300 µm by optical coherence tomography among patients without preoperative DME.Results The cumulative incidence of PV-DME at 3 months was 40.1% (89/222), with its majority subtype of single diffused retinal thickening (66.2%) followed by single cystoid macular edema (27.0%). Multivariate Cox regression analysis indicated that a thicker preoperative CRT (HR = 1.01, 95% CI 1.00–1.02) and intraoperative internal limiting membrane peeling (HR = 3.18, 95% CI 1.85–5.47) were associated with the presence of PV-DME, while intraoperative intravitreal injection of triamcinolone acetonide (HR = 0.28, 95% CI 0.13–0.57) was protective against PV-DME. In eyes with preoperative DME (n = 143), the CRT decreased gradually from 468.3 ± 177.7 µm preoperatively to 409.5 ± 151.0 µm (P = 0.027), 377.4 ± 141.9 µm (P < 0.001), and 368.0 ± 157.6 µm (P < 0.001) at 7 days, 1 month, and 3 months postoperatively, respectively. Multivariate linear regression analysis indicated that only a thicker preoperative CRT (β = 0.77, 95% CI 0.63–0.92) was associated with a decreasing postoperative CRT.Conclusion PV-DME is a very common postoperative complication in patients with proliferative diabetic retinopathy. Triamcinolone acetonide could prevent its formation. Attention should be paid to patients with a thicker preoperative CRT and internal limiting membrane peeling.
Multi-Class Prediction of a Weighted Time-Varying Association Using Artificial Neural Network in Smart Health Environment
Authors: Patra Abhimanyu , Mishra Sarojananda , Senapati Manas Ranjan , BEHERA RAJESH KUMAR , Pani Subhendu Kumar
Published: June 2023

Computerization has been a need in recent years. As a result, massive amounts of digital data have been accumulated in practically every industry. Data mining approaches have arisen to serve with this rich data and sparse informations. Data-mining is a process that uses computers to extract and examine hidden patterns in data. Users may understand and benefit from this data mining process of knowledge discovery. According to the value associated with each property, different weights are allocated to those attributes. Weights assigned by the doctors are taken into consideration in this investigation. The first technique given is multiclass weighted associative classification with confidence-based rule ranking, while the second strategy is enhanced, genetic-based rule selection presented as a final step is a distributed multiclass weighted associative classifier. The distributed weighted associative classification is utilized as a consequence of the findings that lower the cost of communication while maintaining the benefit of the centralized approach. The multi class classification's accuracy % rises while using weighted associative classification.
Enhance arsenic adsorptions by optimizing Fe-loaded biochar and preliminary application in paddy soil under different water management strategies
Authors: Xu Yijie , Huang Manjie , Wang hongyan , Sun Guoxin , Kumar Amit , Yu Zhiguo
Published: June 2023

Arsenic (As) is widely distributed in nature and is a highly toxic element impacting human health through drinking water and rice. In this study, an optimized approach was attempted to improve As adsorption capabilities by combining pre-and-post-pyrolysis modification of Fe(oxy)hydroxides to rice husk biochar (FRB). Maghemite and goethite were successfully loaded onto biochar, characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray photoemission spectroscopy (XPS) analyzer. The FRB had maximum As(III) and As(V) adsorption capabilities of 7908 and 11268 mg/kg respectively, which is significantly higher than that of Fe-modified biochar in the pre-pyrolysis and/or post-pyrolysis process. Adsorption mechanisms for As explored by Fourier-transform infrared spectroscopy (FTIR), XPS analysis mainly included electronical attraction and ligand exchange with hydroxyl groups on the FRB. It was noteworthy that more than half of the As(Ⅲ) species loaded on FRB were converted into less toxic As(Ⅴ) species. The result stated that FRB has an effective remediation potential for As-contaminated soil under flooded conditions while promoted As release under dry conditions. Finding of this study highlighted that the loading of metal oxides onto biochar by combining pre-and-post pyrolysis modification could potentially increase As adsorption capabilities, and further helps in strategic water management.
Effect of Antecedent Hypertension on Mortality after Acute Coronary Syndromes in Coronary Intervention Era: A Meta-analysis
Authors: Qi Shanshan , Zhan Youqin , Chen Yanjun , Xu Tan
Published: June 2023

Background Effect of antecedent hypertension on mortality after acute coronary syndromes (ACS) in the percutaneous coronary intervention (PCI) era is less clear. The aim of this meta-analysis was to assess effect of antecedent hypertension on short and long-term mortality after ACS in the coronary intervention era.Methods PubMed, Medline, EMBASE and the Cochrane library were systematically searched up to April 2023. Ten studies with total of 64, 989 of patients met the inclusion criteria. The outcomes of interest were (i) all-cause in-hospital mortality; (ii) long-term all- cause mortality.Results No significant difference was observed in in-hospital mortality between antecedent hypertension group and non-antecedent hypertension with pooled odds ratio (OR): 1.07, 95% confidence interval (CI): 0.79–1.45; I2 = 82%, the same as ST elevation myocardial infarction (STEMI) group (pooled OR: 1.01, 95% CI: 0.73– 1.39; I2 = 66%). However, result was statistically significant for non-ST elevation myocardial infarction (NSTE-ACS) patients, with pooled OR: 0.67, 95% CI: 0.55–0.82; p = 0.0001, I2 = 0%. Antecedent hypertension was related to increased long-term mortality of patients with ACS (pooled OR 1.28, 95% CI 1.16–1.40, p = 0.0001; I2 = 0%), the same as STEMI subgroups.Conclusion In PCI era antecedent hypertension was associated with higher long-term mortality in ACS patients, but no significant difference was observed in in-hospital mortality between hypertension and non- hypertension. However, for NSTE-ACS patients’ antecedent hypertension may be a protective factor related to in- hospital mortality.
Support Effects in Cu-Mn mixed-oxide Catalysts on Ozone Decomposition under Ambient Temperature
Authors: Li Yunhe , Li Hao , Zhao Baogang , Ma Yanming , Liang Peiyuan , Sun Tianjun
Published: June 2023

Catalytic decomposition is widely regarded as an optimal solution for surface ozone removal. However, catalyst still faces challenges such as poisoning and deactivation in the high humidity environment. Furthermore, the catalytic environment created by the mixed oxides can provide greater clarity regarding their synergistic effects on catalytic ozone decomposition. Support effects on the catalytic ozone decomposition were investigated under ambient temperature, high GHSV, and high humidity levels using the Cu-Mn mixed-oxide catalysts prepared through a simple coprecipitation method. The characterizations revealed that the addition of SiO2 improved the crystallinity of the CuMn2O4 spinel, and resulted in a larger specific surface area, abundant oxygen vacancies, a lower oxidation state of Mn, and an increase in active oxygen species. The Cu-Mn/SiO2 catalyst exhibited remarkable performance on ozone decomposition, achieving 98% ozone conversion and stability for 10 hours under ambient temperature, even when exposed to a gas hourly space velocity of 300 L·g− 1·h− 1 and an RH of 85%. This study deepens the understanding of the catalyst, and offers significant revelations into the creation of water-resistant catalysts with superior performance.
Porous polymer magnetic adsobents for dye wastewater treatment
Authors: Xue Tao , Shao Feifei , Miao Han , Li Xinxin
Published: June 2023

The recent decade has witnessed adsorption technology emerging as an advanced dye wastewater treatment method with great potential and a grand blueprint, in which the specific surface area and active sites of the adsorbent are considered to be the two most important characteristics largely impacting the adsorption performance. Therefore, two kinds of magnetic porous adsorbents (HSF and HSVF) with different specific surface areas and activity sites were fabricated. Both of them exhibit excellent performance with remarkable adsorption capacities for negative dye Sunset yellow (SY). Furthermore, their adsorption kinetic and isotherm were further studied and compared in detail. The results revealed that introducing strong active sites could improve the adsorption capacity and rate effectively even though sacrificing part of specific surface areas, indicating that active sites might play a dominant role during the dye adsorption process. Multiple interactions introduced by the pyridine functional group in the sample HSVF also showed synergistic effects. In addition, the adsorbents could be recycled rapidly by magnetism, which exhibited the advantages of easy-operation.
Therapeutic effect of subretinal injection of alteplase plus Conbercept for acute submacular hemorrhage secondary to polypoid choroidal vasculopathy
Authors: Mao Ziqing , Yu Xiao , Tian Xifeng , Fan Huimin , Zou Yuling , Chen Zhiping , You Zhipeng
Published: June 2023

Objective
To determine the effectiveness and safety of vitrectomy plus subretinal injection of alteplase(tPA) and intravitreal injection of Conbercept for treating polypoid choroidal vasculopathy (PCV) and submacular hemorrhage (SMH).
Methods
This retrospective study included 32 patients (32 eyes) with large SMH and PCV who visited our hospital from January 2021 to September 2021. All patients underwent best-corrected visual acuity (BCVA), spectral domain optical coherence tomography (SD-OCT), ultra-wide angle fundus photography, fundus fluorescein angiography, and indocyanine green angiography before surgery. They were also treated by the same fundus surgeon with subretinal injection of t-PA combined with intravitreal injection of Conbercept. BCVA, ultra-wide angle fundus photography, and SD-OCT were repeated 1, 3, 6, and 12 months. The BCVA, the macular hemorrhage, macular fovea thickness (CMT) and postoperative complications were observed.
Results
The 32 patients (32 eyes) in this study included 20 males and 18 right eyes. The bleeding size was 6.82 ± 1.53 DD, the preoperative BCVA was 1.73 ± 0.44 logMAR and the preoperative CMT was 727.96 ± 236.40µm. Relative to the preoperative, the postoperative BCVA significantly improved at 1, 3, 6, and 12 months (P < 0.001). The final BCVA and the symptom duration were negatively correlated. Thirty patients (93.75%) had complete clearance of the SMH within 1 week postoperatively. The CMT significantly decreased postoperatively (P < 0.001). The frequency of anti-VEGF was 1–8 times (average, 4.2 ± 1.8). No patient has experienced recurrent hemorrhage or other complications.
Conclusion
Subretinal injection of t-PA combined with Conbercept can significantly improve the vision of patients with large acute submacular hemorrhage secondary to PCV.
Identification of Antrophic Activity Interference in the Seismic Catalogue for Banat Region
Authors: Rau Adina Vanciu , Dinescu Raluca , Radulian Mircea , Lungu Mihail
Published: June 2023

Banat region is one of the most active zones in terms of crustal seismicity in Romania. Even though the active seismic monitoring started from early XXth century, the data sets got more performant with the development and expansion of the seismic network monitoring in the late 1970’s. One particularity regarding seismic data acquisition is that in many cases anthropic activity, such as mining and quarry exploitation, interferes with natural seismicity. Our aim is to bring forward a series of data extracted from the ROMPLUS catalogue to identify the anthropic interference. To this we propose a method based on multiple discrimination criteria, such as local time of event occurrence, magnitude, location in respect with the nearest exploitation site, depth and P-wave input analysis (polarity and waveform). Identifying and filtering the anthropic events from the catalogue will result in a better imaging and characterizing of the natural seismic phenomenon in Banat region improving this way the regional seismic hazard assessment.
Fundamental steps and considerations in the analysis of micro- and nanoplastics in wastewaters, sludges, and comparable matrices
Authors: Cavazzoli Simone , Ferrentino Roberta , Scopetani Costanza , Monperrus Mathilde , Andreottola Gianni
Published: June 2023

Micro- and nanoplastics contamination in the environment is a widely recognized problem since these particles have been found in various natural environments and in different foods and beverages. Additionally, these micro- and nanoplastics can act as carriers of harmful organic and inorganic contaminants and pathogens, potentially posing risks to human and ecosystem health. To evaluate the risks posed by plastic pollution, the scientific community must establish standardized methods for quantifying and monitoring the presence and movement of micro- and nanoplastics in the environment. This review discusses the strengths and limitations of commonly used methods for studying these particles in wastewaters, sludges, and similar environmental samples, as well as suggesting potential solutions to address any shortcomings. The final section delves into the chemicals and pathogens linked to plastic particles, and the techniques used to analyse them.
Overcoming Fermionic Sign Problem in Quantum Monte Carlo Computations: Reference System Method
Authors: Iskakov Sergei , Katsnelson Mikhail , Lichtenstein Alexander
Published: June 2023

We have developed a novel strong-coupling perturbation scheme for a general doped Hubbard model around a particle-hole-symmetric reference system, which is free from the fermionic sign problem. Our approach is based on the lattice determinantal Quantum Monte Carlo (QMC) method in both continuous and dis- crete time versions for large periodic clusters in a fermionic bath. By considering the first-order perturbation in the shift of the chemical potential and the second- neighbour hopping, we are able to obtain an accurate electronic spectral function for a range of parameters that correspond to optimally doped cuprate systems at temperatures of up to T = 0.1t, which are challenging to access using straightfor- ward lattice QMC calculations. We also discuss the formation of the pseudogap and the nodal-antinodal dichotomy for a doped Hubbard system with the interac- tion parameter U equal to the bandwidth and the optimal value of the next-nearest- neighbor hopping parameter t′ for high-temperature superconducting cuprates.
Evaluation of metal pollution related with human health risk in freshwater snail Viviparus contectus (Millet, 1813) as a potential bioindicator species in Lake Habitat
Authors: KOCABAŞ Filiz KUTLUYER , AKSU Emsiye GÖKTÜRK , KOCABAŞ Mehmet
Published: June 2023

For the humankind, water quality of natural resources is the most important and freshwater molluscs are used as bioindicators for the evaluation of water quality in biomonitoring studies. Viviparus contectus (Viviparidae: Gastropoda) is a species freshwater snail and consumed by people. Herein, the concentrations of heavy metals heavy metal (Cd, Cr, Pb, As, Zn and Cu) were measured in water and Viviparus contectus samples. The water quality (temperature, pH, and dissolved oxygen) were seasonally determined in water samples. The present study showed that the metal accumulation in the water and soft tissues of freshwater snail were in the order of Pb > Cr = Zn = Cu = Cd = As and Zn > Cu > Pb > Cd > As = Cr, respectively. The elevated levels of heavy metals (As, Cr, Cu, Zn and Hg) were recorded in autumn. Seasonal variations affected significantly Pb concentration in the freshwater snail samples (P < 0.05). EDI (estimated daily intake) values were lower than the recommended tolerable daily intake (TDI) values for adults and the values of HI (hazard index) were lower than 1 for adults. Zn and Pb values in freshwater snail samples were above the limits according to the Turkish Food Codex, FAO/WHO, JECFA and EC limit values. The water analysis indicates mean concentrations of metals below the maximum permissible limits established by the World Health Organization, Turkish Pollution Control Regulation and USEPA, except Pb. Overall, anthropogenic activities adversely affected aquatic ecosystems and this study can be provided a useful data set for metallic contamination in aquatic bodies and biomonitoring studies in freshwater ecosystems.
Saikosaponin D Increases Temozolomide Sensitivity of Glioblastoma via ER Stress-Induced Apoptosis and Autophagy
Authors: Liu Guimei , Liu Xiaobin , Zheng Rui , Zhang Yufu , Han Jiaqi , Guan Yuehong , Guo Shutong , Wang Mingming , Liu Yongxian , Wang Yaping , Zhang Jing , Liu Yusi
Published: June 2023

Background:
Glioblastoma multiforme (GBM) is a primary aggressive brain tumor with high morbidity and mortality. Temozolomide (TMZ) has been applied to the treatment of GBM for over a decade, but TMZ resistance is a major obstacle to preventing the recurrence of GBM after surgery. In this study, the effect of Saikosaponin D (SSD) on increasing TMZ sensitivity was investigated by activating the endoplasmic reticulum (ER) stresspathway.
Methods:
Three GBM cell lines with different sensitivities were selected, including rat RG-2 cells, human U251 cells, and LN-428 cells. Cell viability was detected by the Cell Counting Kit-8 (CCK-8) assay and the plate cloning assay method. Cell morphology was observed by hematoxylin and eosin (HE) staining. The apoptosis and autophagy of GBM cells were determined by Hoechst 33258 and MDC fluorescent staining. The expression and distribution of ER stress proteins (GRP78, CHOP, PERK and ATF6) were detected by Western blotting (WB) and immunocytochemistry (ICC). Meanwhile, the expression and distribution of apoptosis proteins (Caspase-12, Caspase-9, and Caspase-3) and autophagy proteins (Beclin-1 and LC3) were also examined by WB and ICC.
Results:
The CCK-8 proliferation experiment and HE staining results confirmed that TMZ could inhibit the proliferation of GBM cells with the increase of the treatment time and dose. The highest inhibition rate was observed in RG-2 cells, while LN-428 cells exhibited poor sensitivity. Besides, the combined treatment with SSD and TMZ (SSD+TMZ) significantly promoted the apoptosis of GBM cells, compared with single drug administration groups. In addition, the WB experiment results suggested that the expression of ER stress-related proteins (PERK, ATF6, GRP78, and CHOP) was up-regulated. Moreover, apoptotic bodies and damaged nuclei were observed under Hoechst 3328 staining in the SSD+TMZ treatment group. Furthermore, the WB results revealed that Caspase-3, Caspase-9, and Caspase-12 were cleaved, and the expression of these cleaved bodies was up-regulated after the SSD+TMZ treatment. Autophagosomes were observed under MDC staining, and the expression of autophagy proteins (LC3 and Beclin-1) was up-regulated. These results indicated that SSD enhanced TMZ sensitivity of GBM cells via ER stress-induced apoptosis and autophagy.
Hypericin-mediated regulation of miR21 and miR34a and their target genes in MCF7 breast cancer cells
Authors: Norouzi Raana , Ghotbzadeh-kermani Sepideh , Abbaspour Hossein
Published: June 2023

Background: Hypericin is a polyphenolic compound derived from Hypericum perforatum that exhibits anticancer activity in various cancer cell types. The molecular mechanisms of hypericin action on breast cancer cells are unclear. We investigated the effects of hypericin on MCF7 human breast cancer cells and the potential role of miR21 and miR34a in mediating these effects.
Methods and Results: We evaluated the cell viability of MCF7 cells exposed to different concentrations of hypericin for 24 and 48 hours by XTT assay. e treated MCF7 cells with 5 µg/mL concentration of hypericin for 24 hours. We then measured the expression levels of miR21, miR34a, and their target genes PTEN, BCL2, TP53, and CDK4 at both mRNA and protein levels by qRT-PCR and western blotting. Hypericin decreased the cell viability and increased the apoptosis rate of MCF7 cells in a dose- and time-dependent manner. Hypericin also modulated the expression levels of miR21 and miR34a in MCF7 cells. Hypericin upregulated the expression levels of PTEN and TP53 and downregulated the expression levels of BCL2 and CDK4 in MCF7 cells. The changes in gene expression were consistent with the changes in protein expression.
Conclusion: Hypericin induces anticancer effects on MCF7 human breast cancer cells by reducing cell viability, inducing apoptosis, modulating miR21 and miR34a expression, and regulating PTEN, BCL2, TP53, and CDK4 expression. Our findings reveal novel molecular targets and pathways for hypericin action on breast cancer cells and suggest that hypericin may be a promising therapeutic agent for breast cancer treatment.
Electric field stimulation unmasks a subtle role for T-type calcium channels in regulating lymphatic contraction
Authors: Davis Michael J. , Castorena-Gonzalez Jorge A. , Zawieja Scott D.
Published: June 2023

We previously identified two isoforms of T-type, voltage-gated calcium (Cav3) channels (Cav3.1, Cav3.2) that are functionally expressed in murine lymphatic muscle cells; however, contractile tests of lymphatic vessels from single and double Cav3 knock-out (DKO) mice, exhibited nearly identical parameters of spontaneous twitch contractions as wild-type (WT) vessels, suggesting that Cav3 channels play no significant role. Here, we considered the possibility that the contribution of Cav3 channels might be too subtle to detect in standard contraction analyses. We compared the sensitivity of lymphatic vessels from WT and Cav3 DKO mice to the L-type calcium channel (Cav1.2) inhibitor nifedipine and found that the latter vessels were significantly more sensitive to inhibition, suggesting that the contribution of Cav3 channels might normally be masked by Cav1.2 channel activity. We hypothesized that shifting the resting membrane potential (Vm) of lymphatic muscle to a more negative voltage might enhance the contribution of Cav3 channels. Because even slight hyperpolarization is known to completely silence spontaneous contractions, we devised a method to evoke nerve-independent, twitch contractions from mouse lymphatic vessels using single, short pulses of electric field stimulation (EFS). TTX was present throughout to block the potential contributions of voltage-gated Na+ channels in perivascular nerves and lymphatic muscle. In WT vessels, EFS evoked single contractions that were comparable in amplitude and degree of entrainment to those occurring spontaneously. When Cav1.2 channels were blocked or deleted, only small residual EFS-evoked contractions (~ 5% of normal amplitude) were present. These residual, EFS-evoked contractions were enhanced (to 10–15%) by the KATP channel activator pinacidil (PIN) but were absent in Cav3 DKO vessels. Our results point to a subtle contribution of Cav3 channels to lymphatic contractions that can be unmasked in the absence of Cav1.2 channel activity and when the resting Vm is more hyperpolarized than normal.
Perception of parents or guardians of children regarding bruxism in the State of Amazonas
Authors: Dib Amanda Craveiro Carvalho , Dutra André Luiz Tannus , Paiva Saul Martins , Serra-Negra Junia Maria , Lucisano Marília Pacífico
Published: June 2023

Purpose: The objective of this study was to evaluate the knowledge of parents or guardians about bruxism in children who seek care at Pediatric Dentistry Clinics at the State Polyclinic of the State of Amazonas.
Methods: Participation in the study was authorized through the Free and Informed Consent Form. This is a cross-sectional, population-based, observational, randomized, stratified, representative study of parents or guardians of children aged 3 to 12 years. Data were collected from 312 questionnaires.
Results: The prevalence of possible sleep bruxism was found in 11.9% of the parents or guardians and 21.5% of the children. 58.7% said they did not know what bruxism is. Among those who reported knowing that it was only 36.9%, they correlated bruxism with the habit of grinding or clenching their teeth. 74.4% They could not say etiology. Only 8.3% sought help or treatment. Only 5.4% sought a dentist for treatment. 64.1% Have stated that bruxism can affect people's health. Yet 59.3% could not say what it can affect. 88.5% said they would like more information about bruxism.
Conclusion: The number of people who are not aware of sleep bruxism and its etiology is significant. The apparent lack of awareness about bruxism leads them to underestimate the condition, and may lead families not to seek appropriate treatment, increasing the underdiagnosis of the condition.
Using systems thinking to understand scale-up and sustainability of health innovation: a case study of Seasonal malaria chemoprevention processes in Burkina Faso
Authors: Niang Marietou , Gagnon Marie-Pierre , Dupéré Sophie
Published: June 2023

Background: Scale-up and sustainability are often studied separately, with few studies examining the interdependencies between these two processes and the implementation contexts of malaria innovations. Researchers and implementers offer much more attention to the content of innovations, focusing on the technological dimensions and the conditions for expansion. Researchers have often considered innovation a linear sequence in which scaling up and sustainability remained the last stages. Using systems thinking in this manuscript, we aim to analyze the complex scaling and sustainability processes through adopting and implementing Seasonal Malaria Chemoprevention (SMC) in Burkina Faso from 2014 to 2018.
Methods: We conducted a qualitative case study involving 141 retrospective secondary data (administrative, press, scientific, tools and registries, and verbatim), spanning 2012 to 2018. We completed these with primary data collected between February to March 2018, as 15 personal semi-structured interviews with SMC's stakeholders and non-participant observations. Processual analysis permitted us to conceptualize scale-up and sustainability processes over time according to different vertical and horizontal levels of analysis and their interconnections.
Results: Our results indicated six internal and external determinants of SMC that may negatively or positively influence its scale-up and sustainability in time and space. These determinants are effectiveness; monitoring and evaluation systems; resources (financial, material, and human); leadership and governance; adaptation to the local context; and other external elements. Our results revealed that donors and implementing actors prioritized financial resources over other determinants. In contrast, our study clearly showed that the sustainability of the innovation, as well as its scaling up, depends significantly on the consideration of the interconnectedness of the determinants. Each determinant can concurrently constitute an opportunity and a challenge for the success of the innovation.
Conclusion: Our findings highlight the usefulness of the systemic perspective to consider all contexts (international, national, subnational, and local) to achieve large-scale improvement in the quality, equity, and effectiveness of interventions in global health. Thus, complex and systems thinking has made it possible to observe emergent and dynamic innovation behaviors and the dynamics particular to sustainability and scaling up processes.