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Multi-scale Analysis of Surfactant-assisted Enhance Oil Recovery and Carbon Dioxide Geological Utilization
(2024-07-19) Liu, Benjieming; Chen, Zhangxing; Aguilera, Roberto; Maini, Brij; Husein, Maen; Rui, Zhenhua
Ever since the first industrial revolution, the rising trend of energy consumption and greenhouse gas (GHG) emissions never stopped, contributing to the pressing global issue of global warming. The society still has a chance to prevent the worst of climate change’s future harm. Therefore, balancing the increase in energy demand while controlling carbon dioxide (CO2) emissions has become a common goal for humanity. In the oil and gas industry, surfactants have been recently regarded as a viable chemical additive to enhance oil recovery (EOR) and carbon capture, utilization, and storage (CCUS). However, the performance of surfactants in engineering fields has often been assessed too simplistically based on observed changes in their behaviors or properties. In order to provide an in-depth fundamental understanding of surfactant-assisted EOR and CCUS processes across multiple scales, in this thesis, essential mechanisms, including displacing performance, adsorption, diffusion, wettability, miscibility, and feasibility in field applications, were studied by experimental methods, molecular dynamics (MD) simulations, and numerical reservoir simulations. In detail, a) the impact of clay minerals on oil detachment from quartz surfaces during surfactant-assisted thermal recovery processes was evaluated; b) a generalized surface modeling procedure of wettability transition on quartz surfaces was proposed to accurately predict a contact angle on sandstone formations; c) the effect of nanoconfinement on the minimum miscibility pressure (MMP) of a CO2/shale oil/surfactant system was investigated; d) a feasibility case study of a novel CO2-switchable surfactant flooding project was conducted on a targeted reservoir. The results of this thesis proved the versatility of surfactants in EOR and CCUS. It is found that clay minerals are not always detrimental to oil recovery. In fact, some clay contents can enhance an oil detachment process by influencing a spatial distribution of surfactant molecules in nanopores. The proposed generalized surface modeling procedure of quartz wettability in this thesis provided more accurate results than a traditional treatment that fully hydroxylates surface atoms. It successfully captured the trend of wettability transition on a quartz surface while considering a series of parameters, including a surface hydroxyl group density, temperature, surfactants, and crude oil. It was also found that the presence of surfactants can reduce the CO2-shale oil MMP. MMP can be further decreased when considering the nanoconfinement effect, as it intensifies CO2-surfactant interactions and inhibits the tendency of CO2 molecules to self-aggregate. Additionally, applying a CO2-switchable surfactant in chemical flooding significantly increased oil recovery, offering an eco-friendly method for oil production. To conclude, this dissertation deepens the understanding of surfactants in EOR and CCUS at multiple scales. It provides helpful guidance on surfactant-assisted engineering processes in the chemical and petroleum industry.
Strategies to prevent blood loss and reduce transfusion in emergency general surgery, WSES-AAST consensus paper
(2024-07-16) Coccolini, Federico; Shander, Aryeh; Ceresoli, Marco; Moore, Ernest; Tian, Brian; Parini, Dario; Sartelli, Massimo; Sakakushev, Boris; Doklestich, Krstina; Abu-Zidan, Fikri; Horer, Tal; Shelat, Vishal; Hardcastle, Timothy; Bignami, Elena; Kirkpatrick, Andrew; Weber, Dieter; Kryvoruchko, Igor; Leppaniemi, Ari; Tan, Edward; Kessel, Boris; Isik, Arda; Cremonini, Camilla; Forfori, Francesco; Ghiadoni, Lorenzo; Chiarugi, Massimo; Ball, Chad; Ottolino, Pablo; Hecker, Andreas; Mariani, Diego; Melai, Ettore; Malbrain, Manu; Agostini, Vanessa; Podda, Mauro; Picetti, Edoardo; Kluger, Yoram; Rizoli, Sandro; Litvin, Andrey; Maier, Ron; Beka, Solomon G.; De Simone, Belinda; Bala, Miklosh; Perez, Aleix M.; Ordonez, Carlos; Bodnaruk, Zenon; Cui, Yunfeng; Calatayud, Augusto P.; de Angelis, Nicola; Amico, Francesco; Pikoulis, Emmanouil; Damaskos, Dimitris; Coimbra, Raul; Chirica, Mircea; Biffl, Walter L.; Catena, Fausto
Abstract
Emergency general surgeons often provide care to severely ill patients requiring surgical interventions and intensive support. One of the primary drivers of morbidity and mortality is perioperative bleeding. In general, when addressing life threatening haemorrhage, blood transfusion can become an essential part of overall resuscitation. However, under all circumstances, indications for blood transfusion must be accurately evaluated. When patients decline blood transfusions, regardless of the reason, surgeons should aim to provide optimal care and respect and accommodate each patient’s values and target the best outcome possible given the patient’s desires and his/her clinical condition. The aim of this position paper was to perform a review of the existing literature and to provide comprehensive recommendations on organizational, surgical, anaesthetic, and haemostatic strategies that can be used to provide optimal peri-operative blood management, reduce, or avoid blood transfusions and ultimately improve patient outcomes.
Siloed mentality, health system suboptimization and the healthcare symphony: a Canadian perspective
(2024-07-17) Lau, Robin S.; Boesen, Mari E.; Richer, Lawrence; Hill, Michael D.
Abstract
Measuring and optimizing a health system is challenging when patient care is split between many independent organizations. For example, patients receive care from their primary care provider, outpatient specialist clinics, hospitals, private providers and, in some instances, family members. These silos are maintained through different funding sources (or lack of funding) which incentivize siloed service delivery. A shift towards prioritizing patient outcomes and keeping the patient at the centre of care is emerging. However, competing philosophies on patient needs, how health is defined and how health is produced and funded is creating and engraining silos in the delivery of health services. Healthcare and health outcomes are produced through a series of activities conducted by diverse teams of health professionals working in concert. Health professionals are continually learning from each patient interaction; however, silos are barriers to information exchange, collaborative evidence generation and health system improvement. This paper presents a systems view of healthcare and provides a systems lens to approach current challenges in health systems. The first part of the paper provides a background on the current state and challenges to healthcare in Canada. The second part presents potential reasons for continued health system underperformance. The paper concludes with a system perspective for addressing these challenges.
A protocol for the formative evaluation of the implementation of patient-reported outcome measures in child and adolescent mental health services as part of a learning health system
(2024-07-15) McCabe, Erin; Dyson, Michele; McNeil, Deborah; Hindmarch, Whitney; Ortega, Iliana; Arnold, Paul D.; Dimitropoulos, Gina; Clements, Ryan; Santana, Maria J.; Zwicker, Jennifer D.
Abstract
Background
Mental health conditions affect one in seven young people and research suggests that current mental health services are not meeting the needs of most children and youth. Learning health systems are an approach to enhancing services through rapid, routinized cycles of continuous learning and improvement. Patient-reported outcome measures provide a key data source for learning health systems. They have also been shown to improve outcomes for patients when integrated into routine clinical care. However, implementing these measures into health systems is a challenging process. This paper describes a protocol for a formative evaluation of the implementation of patient-reported measures in a newly operational child and adolescent mental health centre in Calgary, Canada. The purpose is to optimize the collection and use of patient-reported outcome measures. Our specific objectives are to assess the implementation progress, identify barriers and facilitators to implementation, and explore patient, caregivers and clinician experiences of using these measures in routine clinical care.
Methods
This study is a mixed-methods, formative evaluation using the Consolidated Framework for Implementation Research. Participants include patients and caregivers who have used the centre’s services, as well as leadership, clinical and support staff at the centre. Focus groups and semi-structured interviews will be conducted to assess barriers and facilitators to the implementation and sustainability of the use of patient-reported outcome measures, as well as individuals’ experiences with using these measures within clinical care. The data generated by the patient-reported measures over the first five months of the centre’s operation will be analyzed to understand implementation progress, as well as validity of the chosen measures for the centres’ population.
Discussion
The findings of this evaluation will help to identify and address the factors that are affecting the successful implementation of patient-reported measures at the centre. They will inform the co-design of strategies to improve implementation with key stakeholders, which include patients, clinical staff, and leadership at the centre. To our knowledge, this is the first study of the implementation of patient-reported outcome measures in child and adolescent mental health services and our findings can be used to enhance future implementation efforts in similar settings.
Workload and spirometry associated with untethered swimming in horses
(2024-07-19) Leguillette, R.; McCrae, P.; Massie, S.; Filho, S. A.; Bayly, W.; David, F.
Abstract
Background
Swimming has been used empirically for rehabilitation and conditioning of horses. However, due to challenges imposed by recording physiological parameters in water, the intensity of free swimming effort is unknown.
Objectives
Measure the physiological workload associated with untethered swimming in horses.
Five fit Arabian endurance horses were assessed while swimming in a 100 m-long indoor pool. Horses were equipped with a modified ergospirometry facemask to measure oxygen consumption (V̇O2) and ventilatory parameters (inspired/expired volumes, VI, VE; peak inspiratory/expiratory flows, PkVI, PkVE; respiratory frequency, Rf; minute ventilation, VE; inspiratory/expiratory durations and ratios, tI, tE, tI/ttot, tE/ttot); and an underwater electrocardiogram that recorded heart rate (HR). Postexercise venous blood lactate and ammonia concentrations were measured. Data are reported as median (interquartile ranges).
Results
Horses showed bradypnea (12 breaths/min (10–16)) for the first 30 s of swimming. V̇O2 during swimming was 43.2 ml/(kg.min) (36.0–56.6). Ventilatory parameters were: VI = 16.7 L (15.3–21.8), VE = 14.7 L (12.4–18.9), PkVI = 47.8 L/s (45.8–56.5), PkVE = 55.8 L/s (38.3–72.5), Rf = 31.4 breaths/min (20.0–33.8), VE = 522.9 L/min (414.7–580.0), tI = 0.5 s (0.5–0.6), tE = 1.2 s (1.1–1.6), tI/ttot = 0.3 (0.2–0.4), tE/ttot = 0.7 (0.6–0.8). Expiratory flow tracings showed marked oscillations that coincided with a vibrating expiratory sound. HR was 178.0 bpm (148.5–182.0), lactate = 1.5 mmol/L (1.0–1.9) and ammonia = 41.0 µmol/L (36.5–43.5).
Conclusions
Free (untethered) swimming represents a submaximal, primarily aerobic exercise in horses. The breathing pattern during swimming is unique, with a relatively longer apneic period at the beginning of the exercise and an inspiratory time less than half that of expiration.