bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Novel Huff-n-Puff Technology for Chemically Shrinking Swelling Clays to Increase Matrix Permeability and Oil Production
Authors: Trost Paul , Wright John 
Published: August 2020

Abstract
A single cycle Huff-n-Puff wellbore remediation of a formation-damaged shallow turbidite sandstone, containing 4-5% illite/montmorillonite, was conducted to 1) chemically shrink the water-damaged swelling clays to increase matrix permeability, and 2) increase production. Chemical reduction of ferric oxides/hydroxides to ferrous oxide in, and on, the surface of swelling clays by a gaseous reducing agent (carbon monoxide-CO) was utilized. Extensive bench-scale and core flood testing have previously demonstrated CO’s ability to chemically increase matrix permeability. Slim tube studies have also demonstrated a mixture of CO2/CO can recover 80-90% of OOIP under immiscible conditions and at less cost than CO2.
Treating depth of the well was 700-820’, having a 146 psi SIP, and a production rate of 0.4 BOPD. Treatment consisted of 1) injecting 70 mcf of CO over 3 day period at an average of 380 psi; 2) shut-in 4 days to allow the CO to react with the ferric ions; 3) injection of 18 Mcf of gaseous CO2 at 400 psi, 4) switch to liquid CO2 injection. After a 48-day shut-in, reservoir pressures again were 146 psi. Pressure transient analysis (PTA) was conducted on the data collected during the injection and falloff of CO and the injection of CO2 gases. During the flowback period, with both gases present, the oil rate was monitored and compared to pre-treatment rates.
PTA showed a 400% increase in gaseous CO2 injectivity compared to the CO rates. Oil production increased 10-fold from 0.4 up to an average of 4 BOPD during the production cycle when CO2/CO was flowing back. After all the CO2/CO was recovered, production dropped to a sustained 1.2 BOPD versus the original 0.4 BOPD for a 300% increase in oil with minor volumes of gas.
Permitting was not an issue. Operational safety was ensured safety meetings and training of personnel combined with CO monitors, flare lines for the CO2/CO, and self-rescuer gas masks. A leak of CO at the wellhead occurred, was safely mitigated, and no safety problems were encountered during subsequent injection and flowback periods.
Measurement of Minimum Miscibility Pressure: A State of the Art Review
Authors: Dindoruk Birol , Johns Russell , Orr Franklin M. 
Published: August 2020

Abstract
This paper gives a critical review of miscibility measurement techniques published in the open literature along with recommendations and lessons learned. Many of these suggested methods violate the assumptions for multicontact miscibility (MCM). The confusion often arises from a failure to distinguish between the first-contact miscibility (FCM), in which two fluids can be mixed in all proportions without forming two phases, and MCM, in which fluid compositions that arise during the flow of two phases in a porous medium approach a specific critical point within the constraints of the MCM definition.
There are many analytical, numerical, correlational, and experimental methods available to estimate the minimum miscibility pressure (MMP) for MCM flow. The numerous available methods, some of which are quite inexpensive, have caused significant confusion in the literature and in practice regarding their ability to estimate MMP. Our experience has shown that the best methods are those that honor the multi-contact process (MCM), in which flow interacts with phase behavior in a prescribed way. Good methods that achieve this are slim-tube experiments, detailed slim-tube smulations, multiple mixing cell calculation methods, and the method-of-characteristics (MOC). Techniques such as the rising bubble apparatus (RBA) and vanishing interfacial tension (VIT) experiments are subject to significant uncertainties, though they may still provide quite useful information. Numerous MMP correlations have been developed. They should be used with caution for systems similarto those used to develop the correlation. Use for other systems can lead to significant errors. We discuss the advantages and disadvantages of most current methods and show that various combinations of methods can reduce uncertainty.
Feasibility Study of Gas Injection in Low Permeability Reservoirs of Changqing Oilfield
Authors: Tian Ye , Uzun Ozan , Shen Yizi , Lei Zhengdong , Yuan Jiangru , Chen Jiaheng , Kazemi Hossein , Wu Yu-Shu 
Published: August 2020

Abstract
Changqing Oilfield is the largest petroleum-producing field in China and one-third of its oil production is attributed to the formations with permeability lower than 1 mD. The rapid oil rate decline and low recovery factor (RF) associated with those formations require additional IOR/EOR measures besides waterflood. Based on the promising results from recent gas injection pilots in North America, we investigated the feasibility of gas injection in the low permeability formation (Chang 63) of Changqing Oilfield.
An eight-component fluid characterization, which fits both the constant composition expansion (CCE) test and separator test, was used in a numerical dual-porosity compositional model. A typical well pattern, composed of six vertical injectors and one horizontal producer, is selected for the modeling study. The input parameters, including relative permeability, fracture permeability, etc., were adjusted to achieve an acceptable history match of the production data. Huff-n-Puff using several gases—lean gas (CH4), produced gas, rich gas (C2H6), and solvent (C3H8)— were investigated and the results were compared with the current waterflood.
The simulation results show that the richer the injected gas, the higher the oil production. C3H8 huff-n-puff achieved the best performance, increasing the cumulative oil production by a factor of 2.28 after 5 cycles, then followed by C2H6 as 1.34, produced gas as 1.08. CH4 alone demonstrated a lower recovery factor than waterflood, because its minimum miscibility pressure (MMP) is close to the maximum allowable injection pressure, i.e., the minimum horizontal stress. In addition, the horizontal producer was completed at the reservoir top and water injectors were placed at the bottom, which was originally designed to improve the waterflood by gravity segregation. Under such well placement design, the miscible oil bank, which forms at the injection front during vaporizing drive, will be displaced towards the reservoir bottom even out of the SRV, undermining the huff-n-puff performance. Injection with rich gas will be more compatible, as the miscible bank forms at the injection tail. Injecting produced gas enriched with C3H8 will hence achieve promising EOR performance. The simulation also shows that increasing injection pressure increases the recovery factor. The leaner composition of produced gas could be compensated by a higher injection pressure. The optimal injection duration and soaking time could also be obtained after sensitivity analysis. Another critical factor is the fracture network characterized by the dual-porosity model, as simulation with the single porosity model only shows minor improvement in RF even with C3H8.
Our work confirmed the technical feasibility of injecting rich gas in the low permeability Chang 63 by compositional simulation. We also determined the key parameters for the operator to consider in the next phase of the project.
Catalytic hydrolysis of Dichlorodifluoromethane over MoO3/ZrO2 -TiO2&nbsp;solid acid
Authors: Li Zhiqian , Zhou Tong , Ren Guoqing , Tan Xiaofang , Jia Lijuan , Liu Tiancheng 
Published: August 2020

Abstract
The catalytic hydrolysis of Difluorodichloromethane(CFC-12) by solid acid of MoO3/ZrO2-TiO2 calcined at different temperature had been studied. The effects of catalytic hydrolysis temperature and water vapor concentration on catalytic hydrolysis of CFC-12were also studied. The results showed that catalytic hydrolysis rate of CFC-12 reached to 98.65 % at 400。C when the MoO3/ZrO2-TiO2 catalyst was calcined at 500℃ with a concentration of water vapor of 83.18% ,and the main hydrolysis products were CO, CO2, HF and HCl. After 30 hours’ continuous reaction, the hydrolysis rate of CFC-12 was 65.34%. The XRD result reveals that the main phase of solid MoO3/ZrO2-TiO2 catalyst is the tetragonal Zr(MoO4)2with dopedTiO2 of anatase.
Cancer treatment with hormone therapy and its relationship with xerostomia and hyposalivation
Authors: Medeiros Glaucia de , Fernandes Jheiniffer , Pompeo Daniela , Pereira Jefferson Ricardo 
Published: August 2020

Abstract
Background: The appearance of new drugs for cancer treatment has increased patient survival but it has also brought adverse effects, such as the sensation of dry mouth and hyposalivation. Objective: To assess the relationship of using hormone therapy in breast and prostate cancer patients and the occurrence of xerostomia and hyposalivation. Method: Cross-sectional study with 114 patients diagnosed with cancer and treated with hormone therapy (anastrozole or bicalutamide). Age, type of neoplasia, sex, presence of xerostomia (yes or no), and type of medication were obtained with a questionnaire. The researcher collected resting and stimulated salivary flows in the morning. The descriptive statistic analysis, chi-square test (p<0.005), and t-test (<0.005) were performed using the Statistical Package for Social Science™ (SSPS), version 21, for different variables of hyposalivation and hormone therapy. Results: The results showed that 67 (55.8%) patients using hormone therapy drugs presented hyposalivation and 73 (64%) patients presented xerostomia. Conclusion: According to the results of this study, there is a positive association between stimulated hyposalivation and the use of hormone therapy drugs (p = 0.015). There was also a positive association between hyposalivation and xerostomia and the use of hormone therapy drugs (p = 0.049 and p = 0.001).
C-Reactive Protein and Lymphocyte are important indicators of severe coronavirus disease and poor prognosis in elderly patients
Authors: He Qinglin , Hu Xiafen , Xiang Xiaochen , Chen Siyang , Liu Wanxin , Liu Xiaoliu , Wang Qiang , Guo Kaiwen , Wu Qingming 
Published: August 2020

Abstract
Objective：To explore the value of C-reactive protein (CRP) and lymphocyte (L) in the assessment of disease severity and prognosis of elderly COVID-19 patients.Methods: A total of 194 positive COVID-19 patients were collected from Tianyou Hospital and Puren Hospital, affiliated hospital of Wuhan University of Science and Technology. Their demographic characteristics were analyzed. The dynamic changes of CRP and L in peripheral blood were retrospectively studied.Results: (1) There were significant statistical differences in CRP, L in clinical typing and clinical outcome in patients over 60 years old compared with those under 60 years old. Survival analysis showed that the risk of death was greater in patients over 60 than in those under 60.（2）In 125 patients over 60 years old, the hospitalized patients with severe or critical types of disease had significantly higher CRP than those with moderate type (p<0.01). In the outcome of the elderly patients, the CRP of the patients with the outcomes of discharge, improvement, aggravation and death increased successively (p<0.01). According to the analysis of Logistic regression model, the increase of CRP constitutes a risk factor for death in elderly patients. (3) In the ROC curve analysis to distinguish the death outcome and non-death outcome of COVID-19 patients, the area under the curve (AUC) of CRP and L was 0.751 and 0.720 respectively. CRP and L had good diagnostic accuracy for the death outcome of patients. (4) Changes in CRP were correlated with changes in CT imaging and were consistent with changes in the course of the disease.Conclusions: (1) The data collected in this research showed that the cumulative survival rate of patients over 60 years old was lower than that of patients under 60 years old. With the increase of age, the CRP of patients showed an increasing trend, and the L of patients showed a characteristic lower than the normal reference interval. (2) CRP and L are important monitoring indicators of COVID-19 in elderly patients. Combined with CT examination and observation of their dynamic changes, CRP and L are of important clinical guiding value for the judgment of disease severity and the evaluation of prognosis.
Comparative study for the treatment of domestic wastewater using Chlorella Vulgaris
Authors: Moondra Nandini , Jariwala Namrata , Christian Robin A 
Published: August 2020

Abstract
Tertiary treatment using chemicals frequently prompts secondary contamination of sludge, making additional issues of safe disposal. Thus, vitality and cost required for tertiary treatment of wastewater stay an issue for industries and municipalities. In this study, different microalgal concentrations 360 mL (20%), 450 mL (25%), 540 mL (30%), 630 mL (35%), 720 mL (40%) and 810 mL (45%) were studied to treat domestic wastewater for 11 hours of detention time for both filtered and non-filtered effluent. During the study, removal was observed in Total Solids (TS), Total Dissolved Solids (TDS), Total Suspended Solids (TSS), Electrical Conductivity (EC), phosphate, ammonia and Chemical Oxygen Demand (COD) for all the microalgal concentrations mentioned. 30% microalgal concentration showed maximum removal efficiency among different microalgal concentrations studied. Maximum removal efficiency found in non-filtered effluents when treated with 30% microalgal concentration was 96.60, 91.73 and 84.71% respectively for ammonia, phosphate and COD concentration. However, the removal efficiency increased to 97.62, 92.47 and 88.75% respectively for ammonia, phosphate and COD in the case of filtered effluents. In the case of TSS and EC, removal efficiency reached up to 30.87 and 24.31% respectively for non-filtered effluents while it was 48.00 and 25.88% respectively, for the filtered effluents. One-way ANOVA was also conducted to determine the statistical significance of the study. The study showed that an algae-based system could accomplish a more affordable and environment-friendly way to treat domestic wastewater without tertiary treatment to a desirable limit.
Treatment of ruptured tiny intracranial aneurysms by electrocoagulation with guidewire manipulation:12 cases report
Authors: Xia Lixia , Hao Zhongfei , Wang Hongjun , Feng Yan , Zhan Yongxuan , Chen Minghui , Xie Peng , Li Qingbin , Li Ruiyan , Liu Yang , Wang Feng , Fang Yuequn , Li Youxiang , Li Yongli 
Published: August 2020

Abstract
Background: Ruptured tiny intracranial aneurysm (RTIA) is particularly rare seen. Treatment of RTIA is more difficult and not under control.Methods: We hereby present twelve rare cases of RTIA that were diagnosed based on DSA. These patients were found due to spontaneous or traumatic SAH, 11 of whom were treated only by electrocoagulation, and one of whom was treated by stent-assisted coiling and electrocoagulation.Results: There were eight patients with aneurysms located in posterior circulation and four patients with aneurysms located in anterior circulation. 11 patients were cured only by electrocoagulation merely: ten patients’ RTIA disappeared completely and immediately and another patient’s RTIA was thrombosed two months later. The twelfth patient was carried out stent-assisted coiling and electrocoagulation. The twelve patients’ average follow-up time was 12.5 months and the outcomes were all surprisingly excellent. No revascularization of aneurysm was found. Conclusions: Electrocoagulation with guidewire manipulation is a suitable method to treat RTIA. While large-scale studies with long-term follow-up are required to validate these promising results.
Effects of Cytokine Blocking Agents on Hospital Mortality in Patients Admitted to ICU With Acute Respiratory Distress Syndrome by SARS-CoV2 Infection: An Observational Cohort Study
Authors: Coloretti Irene , Busani Stefano , Biagioni Emanuela , Venturelli Sophie , Munari Elena , Sita Marco , Dallara Lorenzo , Tosi Martina , Clini Enrico , Tonelli Roberto , Fantini Riccardo , Mussini Cristina , Meschiari Marianna , Guaraldi Giovanni , Cossarizza Andrea , Alfano Gaetano , Girardis Massimo 
Published: August 2020

Abstract
Background The use of cytokine-blocking agents has been proposed to modulate the inflammatory response in patients with COVID19. Tocilizumab and Anakinra were included in the local protocol as an optional treatment in critically ill patients with acute respiratory distress syndrome (ARDS) by SARS-CoV2 infection. This cohort study evaluated the effects of therapy with cytokine blocking agents on in-hospital mortality in COVID19 patients requiring mechanical ventilation and admitted to intensive care unit. Methods The association between therapy with Tocilizumab or Anakinra and in-hospital mortality was assessed in consecutive adult COVID19 patients admitted to our ICU with moderate to severe ARDS. The association was evaluated by comparing patients who receive to those who did not receive Tocilizumab or Anakinra and by using different multivariable Cox models adjusted for variables related to poor outcome, for the propensity to be treated with Tocilizumab or Anakinra and after patient matching. Results Sixty-six patients who received immunotherapy (49 Tocilizumab, 17 Anakinra) and 28 patients who did not receive immunotherapy were included. The in-hospital crude mortality was 30,3% in treated patients and 50% in non-treated (OR 0,77, 95% CI 0,56-1,05, p=0,069). The adjusted Cox model showed an association between therapy with immunotherapy and in-hospital mortality (HR 0,35, 95% CI 0,16-0,77, p=0,009). This protective effect was further confirmed in the analysis adjusted for propensity score, in the propensity-matched cohort and in the cohort of patients with invasive mechanical ventilation within 2 hours after ICU admission. Conclusions Although important limitations, our study showed that cytokine-blocking agents seem to be safe and to improve survival in COVID-19 patients admitted to ICU with ARDS and the need of mechanical ventilation.
Epidemiology and Pathology of Oral Squamous Cell Carcinoma in a Multi-ethnic Population: Analysis of 154 cases over 12 years in Qatar
Authors: Elaiwy Orwa , Ansari Walid El , Al-Khalil Moustafa , Ammar Adham 
Published: August 2020

Abstract
Background: Oral cancer (OC) is a neoplastic process of the oral cavity that has high mortality and significant effects on patients’ aesthetics. Majority of OC is oral squamous cell carcinoma (OSCC) and resection remains the most frequent therapy. Recurrence is the main cause of tumor-related mortality.Material and methods: A retrospective review of patients’ charts in Hamad Medical Corporation studied of 154 adults who were diagnosed as OSCC in between 2006- 2018 . The data extracted was demographic, pathologic and clinical. All patients with oral cavity tumors other than squamous cell carcinoma were excluded.Results: Males comprised the majority of the sample, mean age was 46.93 years. Tongue was the most common location. Majority of the patients were diagnosed at early stages and a small subset of patients had histologically-proven local recurrence.Conclusion: Demographics of OSCC patients in Qatar revealed an unprecedented male predominance with a significant younger portion. Most patients were non-nationals, mainly from South Asia. No significant association was found between age groups and local recurrence against multiple parameters. Improving of follow-up system is suggested.Conclusion: The young male predominance of OSCC patients in Qatar is unprecedented worldwide. Most patients were non-Qataris, mainly from South Asia. Loss of follow-up was a challenge in assessing the long term outcomes of OSCC. Our findings suggest the need for a more vigilant surveillance approach to oral lesions particularly in male South-Asian patients, as well as improving the follow-up strategies.
Determinants of Female Genital Mutilation/Cutting in Khartoum State - Sudan, 2020: A Cross-Sectional Study
Authors: Elnimeiri Mustafa Khidir Mustafa , Abdelbasit Reem Mahmoud Mohamed , Ibrahim Mohanad Kamaleldin Mahmoud , Mingaryous Dimetry Adel Dimetry , Abdelrahim Taqwa Mohieldeen Hamid , Satti Shahenaz Seifaldeen Mustafa 
Published: August 2020

Abstract
Background: Female genital cutting/mutilation (FGC/M) is deeply rooted and widely practiced in Sudan. Although the trend is slowly decreasing, the magnitude is still very high as the procedure has no known benefit but has many consequences. The aim of this study was to identify the causes and the risk factors associated with FGC/M among reproductive-age women in the country.Methods: A community based cross-sectional survey was conducted among 902 women in the reproductive age (15-49) years in Khartoum State-Sudan, sampled proportionate to size using multistage clustering and participants were drawn using systematic probability sampling technique. Data were collected using a standardized administered questionnaire. Statistical analysis was done using bivariate and multivariate logistic regression. Results: Among 902 women who participated in the study, 89% of were married and 48% of them got married for the first time at age less than 20 years. The commonest age for such practice was 6-7 years as stated by about 48% of them. There is a significant association between educational level of participants and practicing FGC/M among their daughters (P value=.0001) with a tendency of the participants who attained a higher educational levels to less subject their daughters to any form of FGC/M. There is a significant association between the type of FGC/M of participants and the type of FGC/M of their daughters (P value=.001) with a tendency of the participants’ daughters to be subjected to clitorectomy rather than pharaonic. 39% of the participants stated that they themselves influenced the decision to subject their daughters to FGC/M while 32% of them stated that the grandmothers influence such a decision. The study revealed 45% of the participants believed in customs and traditions as the main reason for the conduct of FGC/M.Conclusion: The FGC/M was widely practiced by the participants’ families indicating the deeply rooted practice as a social norm. Parental education is inversely associated with practicing FGC/M to their daughters. The socio-cultural reason was the main cause of practicing FGC/M among participants. Therefore, a significant change in factors such as education, and social development might cause a gradual decline in FGC/M.