Pump Time Research Articles

Study on the Predictive Value of a Pulmonary Edema Imaging Score for Delayed Extubation in Patients after Heart Valve Surgery on Cardiopulmonary Bypass.

Delayed extubation with mechanical ventilation after cardiac valve surgery is an important clinical challenge. Early extubation can improve the survival rate and prognosis of patients. The study aims to explore the predictive value of a chest X-ray pulmonary edema imaging score on the first day after surgery for delayed extubation in patients after cardiac valve surgery on cardiopulmonary bypass. Retrospective analysis of the clinical data of patients undergoing cardiac valve surgery under extracorporeal circulation admitted to the intensive care unit of Zhongshan Hospital Affiliated with Fudan University (Xiamen) from January 2020 to October 2023. The patients were divided into an early extubation group according to the postoperative mechanical ventilation time (time: <24 h) and a delayed extubation group (time: ≥24 h). The radiographic assessment of lung edema (RALE) score was performed on the chest X-ray of the patient on the first day after surgery to analyze the correlation between delayed extubation of mechanical ventilation and the chest radiograph RALE score on the first day after surgery and to verify its predictive performance. Significant differences in age, the incidence of hypertension, body mass index (BMI), left ventricular ejection fraction (LVEF), pump time, RALE score, ventilation time, oxygenation index, PaCO2, and brain natriuretic peptide (BNP) levels after the first 24 h were seen between patients who were extubated before and 24 h post operation (p = 0.013, 0.001, 0.034, <0.001, <0.001, <0.001, <0.001, <0.001, 0.014, and <0.001, respectively). No significant differences were observed in the proportion of males and the lactate level after the first 24 h between the two groups (p = 0.792 and 0.191, respectively). The time of mechanical ventilation was positively correlated with the RALE score in all patients, and the correlation coefficient was 0.419; the difference was statistically significant (p < 0.001). Multivariate binary logistic regression analysis with stepwise regression was performed on each research factor, and it was found that RALE score, pump time, oxygenation index, and postoperative BNP were independent risk factors for predicting delayed extubation in patients undergoing cardiac surgery on cardiopulmonary bypass. A 10-fold cross-validation revealed that the mean accuracy, sensitivity, specificity, and area under the curve (AUC) of the regression model were 0.737, 0.749, 0.741, and 0.825, respectively. The RALE score on the chest radiograph on the first day after surgery is an independent risk factor for predicting delayed extubation in patients after cardiac valve surgery on cardiopulmonary bypass and has good predictive value.

Matched pair analysis of the effect of longer hypothermic machine perfusion time on kidney transplant outcomes.

Hypothermic machine perfusion (HMP) has demonstrated benefits in terms of early kidney transplant function compared to static cold storage. While longer preservation times have shown detrimental effects, a previous paired study indicated that longer pump times (the second kidney in a pair) might lead to improved outcomes. To revisit the prior paired study's somewhat unexpected results by reviewing our program's experience. A total of 61 pairs of transplant recipients who received kidneys from the same donor (2012-2021) were analyzed. Patients were divided into two groups depending on whether they were transplanted first (K1) or second (K2). Therefore, the patients in each pair had identical donor characteristics, except for time on the pump. Statistical analyses included Kaplan-Meyer analysis and paired tests, including McNemar's test, student's paired t-test, or Wilcoxon's test, as appropriate. The two groups of recipients had similar demographics (age, body mass index, diabetes, time on dialysis, sensitization and retransplants). Cold ischemic times for K1 and K2 were 8.9 (95%CI: 7.9, 9.8) and 14.7 hours (13.7, 15.8) (P < 0.0001), respectively. Overall, K2 had a higher rate of freedom from biopsy-proven acute rejection at 1 year (P = 0.015). Delayed graft function was less common in K2, 12/61 (20%) than in K1, 20/61 (33%) (P = 0.046). Finally, K2 showed a higher graft survival than K1 (P = 0.023). Our results agree with a previous study that suggested possible advantages to longer pump times. Both studies should encourage further research into HMP's potential anti-inflammatory effect.

Effect of the Förster interaction and the pulsed pumping on the quantum correlations of a two quantum dot-microcavity system in the strong coupling regime

The quantum correlations of a system of two quantum dots with Föster interaction (Γ) in a microcavity with strongly coupled dissipation and a single mode of the electromagnetic field and driven by a laser pulse were studied theoretically, using the formalism of the master equation in Lindbland form. The energy eigenvalues of the system were studied as a function of detuning for the first and second excitation varieties. Concurrence (C), formation entanglement (EoF), mutual information (I) and quantum discord (Q) are studied as a function of time considering different values of Föster coupling, varying the pump times of the simulated laser pulse and pulse intensity. We found a discrepancy between EoF and C as entanglement quantifiers, noting that concurrence reaches much higher values than EoF; so concurrence can indicate results that are well above the EoF. The presence of the Föster interaction favors that the quantum discord is the dominant correlation in the system, which indicates that the system maintains quantum correlations even when the entanglement of the system has disappeared, but that it is affected by the increase in the laser pump time.

Coupling polyatomic molecules to lossy nanocavities: Lindblad vs Schrödinger description.

The use of cavities to impact molecular structure and dynamics has become popular. As cavities, in particular plasmonic nanocavities, are lossy and the lifetime of their modes can be very short, their lossy nature must be incorporated into the calculations. The Lindblad master equation is commonly considered an appropriate tool to describe this lossy nature. This approach requires the dynamics of the density operator and is thus substantially more costly than approaches employing the Schrödinger equation for the quantum wave function when several or many nuclear degrees of freedom are involved. In this work, we compare numerically the Lindblad and Schrödinger descriptions discussed in the literature for a molecular example where the cavity is pumped by a laser. The laser and cavity properties are varied over a range of parameters. It is found that the Schrödinger description adequately describes the dynamics of the polaritons and emission signal as long as the laser intensity is moderate and the pump time is not much longer than the lifetime of the cavity mode. Otherwise, it is demonstrated that the Schrödinger description gradually fails. We also show that the failure of the Schrödinger description can often be remedied by renormalizing the wave function at every step of time propagation. The results are discussed and analyzed.

Critical evaluation of effects of polymer concentrations on the set time and compressive strength of cement slurries

Thickening time and compressive strength of cement slurry are very critical parameters in well cementing. Thickening or pump time and compressive strength of cement slurries are greatly affected by the slurry weight and temperature. Conventional Lead slurries usually require extenders such as bentonite and some polymers to stabilize the slurry and minimize excessive free fluid. The low slurry weight of lead slurries usually give rise to long pumping or set time and low compressive strength. Some of the polymers also retard the setting of the cement slurry. Therefore, this study focuses on the investigation of the performance of sodium silicate in comparison with gypsum and polyanionic cellulose (PAC-R) as extenders for cement slurries. The concentration of the light weight additives tested were 0%, 1.5% and 3.0% by weight of cement (bwoc) for 12.5ppg slurry using sea water. The slurry stability, compressive strength and quick set time were determined at room temperature. The higher the concentration of the lightweight additives, the more stable is the slurry, best stability was observed for recipe with sodium silicate while the slurry with PAC-R could not mix at 3% bwoc. At the lower concentrations, for sodium silicate, compressive increases and decreases for gypsum. The mixture with PAC-R had zero compressive strength. The gypsum has retarding effect on the slurry while the sodium silicate has accelerating effect. Conclusively, sodium silicate and gypsum powder performed very well as cement extender at optimum concentration, with the former showing the best performance and impacting accelerating properties that will be useful fort low temperature cementing.

Temporal Analysis in Outcomes of Long-Term Mechanical Circulatory Support: Retrospective Study.

Mechanical assist device indications have changed in recent years. Reduced incidence of complications, better survival, and the third generation of mechanical support devices contributed to this change. In this single-center study, we focused on two time periods that are characterized by the use of different types of mechanical support devices, different patient characteristics, and change in the indications. The data were processed from the European Registry for Patients with Mechanical Circulatory Support (EUROMACS). We retrospectively defined two time intervals to reflect changes in ventricular assist device technology (period 1: 2007-2015; period 2: 2016-20222). A total of 181 patients underwent left ventricular assist device implantation. Device utilization was the following: HeartMate II = 52 (76.4%) and HeartWare = 16 (23.6%) in period 1 and HeartMate II = 2 (1.8%), HeartMate 3 = 70 (61:9%), HeartWare = 29 (25.7%), SynCardia TAH = 10 (8.8%), and BerlinHeart EXCOR = 2 (1.8%) in period 2. The outcomes of the time intervals were analyzed and evaluated. Survival was significantly higher during the second time period. Multivariate analysis revealed that age and bypass pump time are independent predictors of mortality. Idiopathic cardiomyopathy, bypass time, and the Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) score are independent predictors of adverse events. Furthermore, the first period was noted to be at an increased risk of the following adverse events: pump thrombosis, gastrointestinal bleeding, and bleeding events. Despite the higher risk profile of the patients and persistent challenges, during the second period, there was a significant decrease in mortality and morbidity. The use of the HeartMate 3 device may have contributed to this result.

H2 chirped-probe-pulse femtosecond coherent anti-Stokes Raman scattering thermometry at high temperature and pressure

This article describes the development and application of hydrogen (H2) chirped-probe-pulse femtosecond coherent anti-Stokes Raman scattering (CPP fs CARS) in high-temperature and high-pressure conditions. H2 fs CARS thermometry was performed in Hencken burner flames up to 2300 K, as well as in a heated gas-cell at temperatures up to 1000 K. It was observed that the H2 fs CARS spectra are highly sensitive to the pump and Stokes chirp. Chirp typically originates from optical components or systems such as windows, polarizers, and the optical parametric amplifier. As a result, the pump delay is modeled to provide a shift to the Raman excitation efficiency curve. With the updated theoretical model, excellent agreement was found between the simulated and experimental spectra. The mean error and precision are 2.8% and 2.3%, respectively. In addition, the spectral phase of the input pulses and the pump time delay determined from the experimental spectra closely align with the theoretical predictions. It is also found that pressure does not have significant effects on the H2 fs CARS spectra up to 5 MPa at 1000 K. The collision model provides excellent agreement with the experiment. This allows the use of low-pressure laser parameters for high-pressure thermometry measurements.

Development and validation of a clinical prediction model for early ventilator weaning in post-cardiac surgery

BackgroundWeaning patients from mechanical ventilation is a critical clinical challenge post cardiac surgery. The effective liberation of patients from the ventilator significantly improves their recovery and survival rates. This study aimed to develop and validate a clinical prediction model to evaluate the likelihood of successful extubation in post-cardiac surgery patients. MethodA predictive nomogram was constructed for extubation success in individual patients, and receiver operating characteristic (ROC) and calibration curves were generated to assess its predictive capability. The superior performance of the model was confirmed using Delong's test in the ROC analysis. A decision curve analysis (DCA) was conducted to evaluate the clinical utility of the nomogram. ResultsAmong 270 adults included in our study, 107 (28.84%) experienced delayed extubation. A predictive nomogram system was derived based on five identified risk factors, including the proportion of male patients, EuroSCORE II, operation time, pump time, bleeding during operation, and brain natriuretic peptide (BNP) level. Based on the predictive system, five independent predictors were used to construct a full nomogram. The area under the curve values of the nomogram were 0.880 and 0.753 for the training and validation cohorts, respectively. The DCA and clinical impact curves showed good clinical utility of this model. ConclusionDelayed extubation and weaning failure, common and potentially hazardous complications following cardiac surgery, vary in timing based on factors such as sex, EuroSCORE II, pump duration, bleeding, and postoperative BNP reduction. The nomogram developed and validated in this study can accurately predict when extubation should occur in these patients. This tool is vital for assessing risks on an individual basis and making well-informed clinical decisions.

Expanding the bandwidth of fluorescence-detected two-dimensional electronic spectroscopy using a broadband continuum probe pulse pair.

We demonstrate fluorescence-detected two-dimensional electronic spectroscopy (F-2DES) with a broadband, continuum probe pulse pair in the pump-probe geometry. The approach combines a pump pulse pair generated by an acousto-optic pulse-shaper with precise control of the relative pump pulse phase and time delay with a broadband, continuum probe pulse pair created using the Translating Wedge-based Identical pulses eNcoding System (TWINS). The continuum probe expands the spectral range of the detection axis and lengthens the waiting times that can be accessed in comparison to implementations of F-2DES using a single pulse-shaper. We employ phase-cycling of the pump pulse pair and take advantage of the separation of signals in the frequency domain to isolate rephasing and non-rephasing signals and optimize the signal-to-noise ratio. As proof of principle, we demonstrate broadband F-2DES on a laser dye and bacteriochlorophyll a.

Comparison of platelet activation in patients undergoing coronary bypass surgery with conventional and mini extracorporeal systems

Aim: The aim of this study was to compare platelet activation in patients undergoing coronary bypass surgery with conventional and mini extracorporeal systems. Material and Methods: Our study is a retrospective study and a total of 116 patient data were obtained. Patients were divided into two groups as conventional extracorporeal and mini extracorporeal system bypass patients. Equal numbers of patients (n=58) were included in both groups. The data of patients who underwent coronary bypass surgery with conventional and mini extracorporeal systems between January 2022 and December 2022 were included in the study. Results: In our study, no significant difference was found between patients bypassed with conventional and mini extracorporeal system in terms of pump time and cross-clamp time. Although the duration of intensive care unit stay and total hospitalization were found to be shorter in patients bypassed with the mini-extracorporeal (MECC) system than those bypassed with the conventional method, the difference between the groups was not significant. As a result of our study, it was observed that postoperative ejection fraction (EF) values significantly increased and hematocrite (HTC), hemoglobin (Hb), platelet (PLT) and procalcitonin (PCT) values significantly decreased in both groups of patients who underwent bypass with conventional and MECC system, and no significant difference was found between pre- and postoperative mean platelet volume (MPV) and platelet distribution width (PDW) values. As a result of our study, postoperative PLT and PCT values in the MECC group were found to be significantly higher than those in patients who underwent bypass with the conventional method. Conclusion: Considering the results obtained in our study, it is seen that the values in patients bypassed with the MECC system are more favorable than those bypassed with the standard method, but more studies on the subject are needed.

Time-dependent wave-packet approach to the excited-state intramolecular proton transfer based on relaxed potential energy surfaces of benzimidazole molecule

The wave-packet dynamical approach was used to investigate the excited-state intramolecular proton transfer (PT) of 5′-amino-2-(2′-hydroxyphenyl) benzimidazole (P1) based on the relaxed potential surfaces. For the involved PT process of P1 molecule, the quantum chemical calculation shows that relative to the ground state S0 with a single potential well, the excited state S1 with a double potential well can give much dynamical information. It is also found that because of the existence of a shallow potential barrier on the excited state S1, the PT in it is much easier than that in the ground state S0. When a laser field is used to pump the wave packet and induce the PT process, the external field parameters, such as the frequency and the envelope, also have influences on the PT process because of the impact of both pump time and the energy gap between two states. This kind of external field effect on the PT process gives a specific perspective to examine its dynamical mechanism and provides a reference for exploring the light-induced biophysical processes.

NLR and PLR as an indicator of outcomes following uneventful cardiac surgery

Background: Patients with coronary artery disease and valvular heart diease continue to be referred for cardiac surgery after medical management fails or in cases where it isn’t feasible. These patients are susceptible to infection and inflammation due to previous MI, cardiopulmonary bypass and the stress associated with surgery itself. Most of these patients also have associated co-morbidities that further increases the risk of post-operative complication. Neutrophil/lymphocyte ratio (NLR) and Platelet/lymphocyte ratio (PLR) is a gaining popularity as a marker of inflammation. Hence we conducted this study to see if NLR and PLR can be used as indicators of outcomes following uneventful cardiac surgery. Methods: A retrospective study was performed on patients undergoing off-pump CABG, on-pump CABG and valve surgeries. Demographic details was noted of all the patients. Postoperative outcomes such as ST-T changes, other arrhythmias, acute kidney/liver injury, wound infection or LRTI within 7 days of surgery was noted and documented. Surgery related factors- cross clamp time, bleeding, challenges in weaning off bypass and operative time were also recorded. Preoperative, day 1, and day 2 NLR and PLR was recorded. Results: Two hundred and six patients in the study. Elevated Pre-op and post-op NLR and reduced PLR values was significantly associated with post-operative ST-T changes and LRTI, with a weak positive correlation between NLR and wound discharge. Additionally, we found that NLR and PLR showed a weak negative correlation with type II diabetes mellitus, pump time/ surgery time &gt; 120 minutes and patients with history of recent MI. Higher preoperative NLR and reduced PLR was significantly associated with postoperative acute liver injury. Conclusions: Higher preoperative and postoperative NLR and reduced PLR is associated with higher rates of complications post-cardiac surgery.

The result of prospective evaluation of 3-dimensional printing-aided extensive thoracoabdominal aorta repair.

Paraplegia is a distressing complication after open thoracoabdominal aortic aneurysm (TAAA) repair, and revascularization of T8-L2-level segmental arteries is considered pivotal to prevent paraplegia. We employed 3-dimensional (3D) printing to efficiently revascularize segmental/visceral arteries and prospectively evaluated its safety and efficacy. From January 1, 2020, to June 30, 2022, we prospectively enrolled patients of extent I, II, or III TAAA repair. Guidance models were 3D-printed based on preoperative computed tomography, and multibranched aortic grafts were manually constructed upon this model before surgery. The composite outcome of operative mortality, permanent stroke, and permanent spinal cord deficit (SCD) was compared with the historical control group (n=77, in 2015-2020), subjected to similar TAAA repair without 3D printing. A total of 38 patients (58.6± 13.2years) underwent open TAAA repair with the aid of 3D printing. Extent I, II, and III repairs were performed in 14 (36.8%), 17 (44.7%), and 7 (18.4%), respectively. Concomitant arch repair and bi-iliac reconstruction were performed in 7 (18.4%) and 6 patients (15.8%), respectively. Mean pump time was 107.7± 55.5minutes. Operative mortality, permanent stroke, and permanent SCD each occurred in 1 patient (2.6%), and the incidence of the composite outcome was 7.9% (3/38). In the control group, mean pump time was 166.0± 83.9minutes, significantly longer than the 3D-printing group (P<.001), and operative mortality, permanent stroke, permanent SCD, and the composite outcome occurred in 7 (9.1%), 9 (11.7%), 8 (10.4%), and 19 (24.7%), respectively. Open repairs of extensive TAAA with 3D printing showed favorable safety and efficacy, which need further validation by larger studies.

Single-Center, Multisurgeon Experience with a Sutureless Rapid Deployment Aortic Valve Prosthesis: A Clinical Analysis in the United States

Background. The Perceval S is a sutureless, bovine pericardial aortic prosthesis on a nitinol stent, which has limited data on outcomes, as well as cost, from the United States. Methods. We performed a retrospective review of Perceval S implantation at a single center between 2015 and 2018. After exclusion criteria, we compared 234 patients who underwent sutureless aortic valve (SLV) implantation with 370 patients who underwent standard sutured aortic valves (SAVR). Hospital cost data were reviewed, and risk adjustment, done by propensity score and inverse probability weighting, was used to compare outcomes. Results. Compared to those undergoing SAVR, the SLV group was older and had a higher proportion of multicomponent operations, higher preoperative white blood cell count, higher rate of previous percutaneous coronary interventions, more comorbid conditions (diabetes, renal insufficiency, and dialysis), and more three-vessel coronary disease. For isolated AVR, partial upper hemisternotomy was more frequent in SLV. The mean cardiopulmonary bypass and cross-clamp times for isolated SLV were significantly lower than SAVR. After adjustment, the cohort was balanced. Operative differences for SLV were lower cross-clamp and pump time, larger valve size, more minimally invasive approaches, and shorter operating room times. There were no differences in other postoperative complications (postoperative atrial fibrillation, stroke, renal failure, prolonged ventilation, and in-hospital mortality; p &gt; 0.05 for all). Mean and median hospital costs were higher in the SLV group, largely due to the cost of the implant. Conclusion. Sutureless tissue aortic valves can be used safely with lower cardiopulmonary bypass and clamp times than sutured prostheses and facilitate use of minimally invasive approaches. This valve may be advantageous in older, higher risk patients requiring more complex operations.

Long-term outcomes of surgical aortic valve replacement in patients receiving chronic dialysis.

Surgical aortic valve replacement (SAVR) has been the standard treatment for symptomatic severe aortic stenosis, which is common among patients receiving long-term dialysis. The aim of this study was to report the long-term outcomes of SAVR in patients receiving chronic dialysis and to identify independent risk factors for early and late mortality. Every consecutive patient with SAVR with or without concomitant cardiac procedures in British Columbia between January 2000 and December 2015 was identified from the provincial cardiac registry. The Kaplan-Meier method was used to estimate survival. Univariate and multivariable models were conducted to determine independent risk factors for short-term mortality and reduced long-term survival. Between 2000 and 2015, 654 patients receiving dialysis underwent SAVR with or without concomitant procedures. The mean follow-up was 2.3 (standard deviation 2.4) years (median 2.5 yr). The overall 30-day mortality was 12.8%. The 5-year and 10-year survival rates were 45.6% and 23.5%, respectively. Twelve patients (1.8%) had redo aortic valve surgery. There was no difference in 30-day mortality or long-term survival between 2 age groups (> 65 yr v. ≤ 65 yr). Anemia and cardiopulmonary bypass (CPB) were independent risk factors for both longer hospital stay and reduced long-term survival. The impact of CPB pump time on mortality occurred mainly within the first 30 days after surgery. When CPB pump time extended beyond 170 minutes, there was a significant increase in 30-day mortality with further prolongation of CPB pump time, and the relationship between 30-day mortality and CPB pump time became approximately linear. Patients receiving dialysis have poor long-term survival with a very low rate of redo aortic valve surgery following SAVR with or without concomitant procedures. Older age (> 65 yr) is not an independent risk factor for either 30-day mortality or reduced long-term survival. Using alternative strategies to limit CPB pump time is an important way to reduce 30-day mortality.

Optical Pump Terahertz Probe (OPTP) and Time Resolved Terahertz Spectroscopy (TRTS) of emerging solar materials

Photoconductivity is the crucial benchmark to assess the potential of any emerging material for future solar applications. Many optical techniques, like transient absorption and photoluminescence, explore bound electron states and provide indirect access to photoconductivity. Direct current (DC) measurements under solar simulation determine the total performance of a novel solar device. While this technique has a clear appeal, it involves electrical contacts, causing contact resistance, which impacts the measured conductivity. Furthermore, DC measurements do not provide any insight into ultrafast effects and the photophysics defining a novel material. Terahertz (THz) spectroscopy presents a contact-free technique to measure photoconductivity on a sub-ps time scale. These measurements can be performed on as-synthesized sample materials, including powders. The ultrafast time resolution informs us of trapping dynamics and reveals what physical processes limit the carrier lifetime in a novel material. Additionally, complex conductivity can be measured at THz frequencies. THz-conductivity and photoconductivity shed light on scattering effects, providing a road map toward minimizing these effects. However, THz spectroscopy is less intuitive than widely used DC measurements, and the interpretation of THz-results is more challenging. This tutorial aims to familiarize the reader with the main THz techniques used to explore emerging materials. We will illustrate how carrier lifetimes can be extracted from optical pump THz probe measurements. We will guide the reader through the process of extracting accurate photoconductivities from time resolved THz spectroscopy measurements and present the most commonly used models to describe the underlying physics. We will then discuss the difference between sample and material parameters and highlight potential pitfalls. The tutorial concludes with a perspective view on the ever evolving field of optical pump-THz probe spectroscopy of emerging materials.

1165-P: 4T Study—Changing Clinical Processes Increases Technology Use at T1D Diagnosis

Use of diabetes technology (CGM, pump) is recommended for people with T1D, and early CGM initiation leads to improved glucose values. We compare %CGM and %pump use and time to initiation from T1D diagnosis in the Historical cohort, 4T Pilot, and 4T Study 1 and the associated workflow changes to increase early technology use. CGM initiation within 30 days of diagnosis increased from 2% in the historical cohort to 92% in Pilot 4T to 98% in 4T Study 1 (Table). Days to pump initiation from TID diagnosis decreased from 272 in the historical cohort to 144 days in Study 1. From 2014-2016 pumps and CGM were initiated when families expressed interest or if the provider discussed them. Families were required to attend a pre-pump class where the CDCES introduced pumps and CGMs prior to starting technology. During the 4T Pilot and 4T Study 1, CGMs were introduced and started during the first month of diagnosis. In Study 1, families were encouraged to attend pump class and initiate AID. The CDCES team does the CGM teach, CGM follow-up, pre-pump classes, and insulin pump starts for the families in preferred language. In 4T Study 2 (enrolling) standard of care is to complete a pre-pump class in the first 3 months after diagnosis. Changes in processes can lead to early implementation of diabetes technology. A structured, team-based process to introduce, reduce barriers, and encourage families to utilize diabetes technology increases early initiation. Disclosure B.P.Conrad: Advisory Panel; Edgepark medical supplies, Consultant; Abbott Diabetes. P.Prahalad: None. D.M.Maahs: Advisory Panel; Medtronic, LifeScan Diabetes Institute, MannKind Corporation, Consultant; Abbott, Research Support; Dexcom, Inc. F.K.Bishop: None. J.Leverenz: None. A.Chmielewski: None. P.Sagan: None. J.Senaldi: None. A.Martinez-singh: None. S.Lin: None. I.Chan: None. Funding National Institute of Diabetes and Digestive and Kidney Diseases (R18DK122422); The Leona M. and Harry B. Helmsley Charitable Trust (G-2002-04251-2); International Society for Pediatric and Adolescent Diabetes/JDRF (1P30DK, 11607401); Lucile Packard Child

ISCHEMIC STROKE AFTER CORONARY BYPASS SURGERY IN PATIENTS WITH TYPE 2 DIABETES, HYPERTENSION, AND TRIPLE VESSEL DISEASE

Objective: We want to investigate this case, what are the various Risk factors for Ischaemic stroke as a major complication, and how to reduce this life-threatening complication in high-risk patients with diabetes, hypertension, and triple vessel disease. Design and method: A 55-year-old patient with TVD Tripple vessel disease without acute MI (myocardial infarction) needed CABG. His angiographic score and uncontrolled diabetes suggested open heart surgery. He did not have carotid or aortic plaque or other issues during the pre-op examination. He underwent on-pump CABG, cardiac aortic bypass with two saphenous veins (on the RCA and OM1), and anastomosis of the left internal thoracic artery on the LAD. The pumping duration was 150 minutes. The patient was weaned from the pump, the surgery was completed, the sternum was closed, and the patient was transferred to the intensive care unit. When we decided to extubate the patient after 12 hours, we noticed his limb movement was not symmetrical. He was paralyzed on the left side. There was significant left hemisphere ischemia on brain CT, which was consistent with CVA. Once brain hemorrhage was excluded, the neurologists started administering heparin to treat the ischemic stroke. Results: Patients with severe stenosis and 3VD require intervention or CABG treatment; however, in this instance, the areas of stenosis were not appropriate for stenting, and the patient's uncontrolled diabetes was another reason suggestive of open-heart surgery. Three crucial aspects have shocked us and that all surgeons may find challenging. Uncontrolled diabetes can significantly contribute to the damage of medium and small blood vessels, and chronic hypertension can cause micro tears and blood clots in the vessels. These three variables can result in tiny damage. Long pump time and these two variables contributed to blood stagnation in the patient. In addition, the patient may have been more vulnerable to ischemic attacks. Conclusions: We may have avoided this complication by administering the following measures

Sequence-Based Target Coin Prediction for Cryptocurrency Pump-and-Dump

With the proliferation of pump-and-dump schemes (P&amp;Ds) in the cryptocurrency market, it becomes imperative to detect such fraudulent activities in advance to alert potentially susceptible investors. In this paper, we focus on predicting the pump probability of all coins listed in the target exchange before a scheduled pump time, which we refer to as the target coin prediction task. Firstly, we conduct a comprehensive study of the latest 709 P&amp;D events organized in Telegram from Jan. 2019 to Jan. 2022. Our empirical analysis reveals some interesting patterns of P&amp;Ds, such as that pumped coins exhibit intra-channel homogeneity and inter-channel heterogeneity. Here channel refers a form of group in Telegram that is frequently used to coordinate P&amp;D events. This observation inspires us to develop a novel sequence-based neural network, dubbed SNN, which encodes a channel's P&amp;D event history into a sequence representation via the positional attention mechanism to enhance the prediction accuracy. Positional attention helps to extract useful information and alleviates noise, especially when the sequence length is long. Extensive experiments verify the effectiveness and generalizability of proposed methods. Additionally, we release the code and P&amp;D dataset on GitHub https://github.com/Bayi-Hu/Pump-and-Dump-Detection-on-Cryptocurrency, and regularly update the dataset.

Experimental Investigation of Geopolymers for Application in High-Temperature and Geothermal Well Cementing

Summary With recurrent calls for a reduction in carbon emissions, geothermal (GT) energy has received increasing attention in recent years as a prominent source of clean energy. With current drilling technology, GT wells are being constructed in extremely challenging temperature environments, which could reach more than 600°F (315°C) in situ. However, GT well-cementing technology has not changed much over the past few decades, with ordinary Portland cement (OPC) still being the primary choice of cementing material. OPC has several drawbacks, including brittle behavior, shrinkage upon setting, poor bond strength to formation and casing, susceptibility to an acid gas attack, temperature-induced strength retrogression, and low tolerance toward drilling fluid contamination. These factors could lead to a poor cementing job, thus compromising well integrity and not ensuring proper zonal isolation for the life of the GT well. Thus, there is a need to develop an alternative material that is compatible with the GT environment and able to provide long-term zonal isolation. With a low carbon footprint, self-healing ability, and low shrinkage sensitivity, geopolymers or alkali-activated materials could be a suitable option to augment or even replace OPC. Some of the previous studies on geopolymers have shown that they could be a potential candidate for oil and gas well cementing and civil engineering applications, with some being stable at very high temperatures [up to 1,470°F (800°C)]. Geopolymers are formed by mixing an aluminosilicate source such as fly ash (FA) with an alkali-activating solution, such as sodium or potassium hydroxide or silicate. The aim of the study reported here is to demonstrate the applicability of geopolymers for GT well cementing. An experimental investigation was carried out to understand the behavior of geopolymer formulations made from FA, metakaolin (MK), and blast furnace slag in a high-temperature environment. The material properties such as porosity, viscosity, thickening/pump time, compressive strength, tensile strength, and bond strength were tested in the laboratory. It was found that geopolymer can be formulated to have the desired rheological properties with adequate pump time and resistance to drilling fluid contamination. In addition, the formulations can exceed the required compressive and tensile strength for GT cementing operations, while obtaining excellent bond strength values. These findings indicate that geopolymers are well-suited to provide long-term zonal isolation in high-temperature GT wells.