Study on the Effect of Two-Stage Injection Strategy for Coal-to-Liquid/Gasoline Reactivity-Controlled Compression Ignition Combustion Mode.

An experimental study was carried out on a modified single-cylinder dual-fuel engine in reactivity-controlled compression ignition (RCCI) mode using pilot fuels with different physicochemical properties, and the effects of the pilot fuels and the two-stage injection strategy on the combustion and emission characteristics of the RCCI mode were explored. The results show that when coal-to-liquid (CTL) is used with a high cetane number as the pilot fuel, the reactivity stratification of the fuel-air mixture is more pronounced. With the advancement of pilot injection timing (SOI1), the heat release rate (HRR) of the CTL/gasoline mode gradually changes from a bimodal pattern to a unimodal pattern. Among them, the bimodal HRR includes CTL premixed combustion and gasoline flame propagation, as well as CTL diffused combustion and gasoline multipoint spontaneous combustion, while the unimodal HRR represents CTL premixed combustion and gasoline multipoint spontaneous combustion. However, the HRR of the fossil diesel/gasoline RCCI combustion mode always exhibits a unimodal form. With the advancement of the main injection timing (SOI2), the gravity center of heat release (CA50) is more advanced when using CTL as the pilot fuel due to the short ignition delay. Overall, compared to fossil diesel, using CTL as the pilot fuel is conducive to controlling the pressure rise rate, which expands the operating range of the RCCI combustion mode. Besides, for both pilot fuels of CTL and fossil diesel, the advancement of SOI1 lowers particle emissions, and the advancement of SOI2 reduces NOx emissions, while the two-stage injection achieves higher indicated thermal efficiency.

Effect of esketamine combined with pregabalin on acute postsurgical pain in patients who underwent resection of spinal neoplasms: a randomized controlled trial.

ABSTRACT: Moderate-to-severe acute postsurgical pain (APSP) can prolong the recovery and worsen the prognosis of patients who undergo spinal surgery. Esketamine and pregabalin may resolve APSP without causing hyperpathia or respiratory depression after surgery. However, there are other risks, such as dissociative symptoms. We designed a randomized controlled trial to investigate the effect of the combination of these 2 drugs on the incidence of APSP in patients who underwent resection of spinal neoplasms. Patients aged 18 to 65 years were randomized to receive esketamine (a bolus dose of 0.5 mg·kg-1 and an infusion dose of 0.12 mg·kg-1·h-1 for 48 hours after surgery) combined with oral pregabalin (75-150 mg/day, starting 2 hours before surgery and ending at 2 weeks after surgery) or an identical volume of normal saline and placebo capsules. The primary outcome was the proportion of patients with moderate-to-severe APSP (visual analog scale score ≥ 40) during the first 48 hours after surgery. Secondary outcomes included the incidence of drug-related adverse events. A total of 90 patients were randomized. The incidence of moderate-to-severe APSP in the combined group (27.3%) was lower than that in the control group (60.5%) during the first 48 hours after surgery (odds ratio = 0.25, 95% CI = 0.10-0.61; P = 0.002). The occurrence of mild dissociative symptoms was higher in the combined group than in the control group (18.2% vs 0%). In conclusion, esketamine combined with pregabalin could effectively alleviate APSP after spinal surgery, but an analgesic strategy might increase the risk of mild dissociative symptoms.

Effects of Ketamine on Chronic Postsurgical Pain in Patients Undergoing Surgery: A Systematic Review and Meta-analysis.

BACKGROUND: Chronic postsurgical pain (CPSP) has become a common complication during the perioperative period. The efficacy of one of the most potent strategies, ketamine, remains unclear. OBJECTIVES: The aim of this meta-analysis was to evaluate the effect of ketamine on CPSP in patients undergoing common surgeries.. STUDY DESIGN: Systematic review and meta-analysis. METHODS: English-language randomized controlled trials (RCTs) published in MEDLINE, Cochrane Library, and EMBASE from 1990 through 2022 were screened. RCTs with a placebo control group that evaluated the effect of intravenous ketamine on CPSP in patients undergoing common surgeries were included. The primary outcome was the proportion of patients who experienced CPSP 3 - 6 months postsurgery. The secondary outcomes included adverse events, emotional evaluation, and 48 hour postoperative opioid consumption. We followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Pooled effect sizes were measured using the common-effects model or random-effects model, and several subgroup analyses were conducted. RESULTS: Twenty RCTs were included with 1,561 patients. Our pooled meta-analysis showed a significant difference between ketamine and placebo in the treatment of CPSP (Relative Risk [RR] = 0.86; 95% CI, 0.77 - 0.95; P = 0.02; I2 = 44%). In the subgroup analyses, our results indicated that compared with placebo, intravenous ketamine might decrease the prevalence of CPSP 3 - 6 months postsurgery (RR = 0.82; 95% CI, 0.72 - 0.94; P = 0.03; I2 = 45%). For adverse events, we observed that intravenous ketamine might lead to hallucinations (RR = 1.61; 95% CI, 1.09 - 2.39; P = 0.27; I2 = 20%) but did not increase the incidence of postoperative nausea and vomiting (RR = 0.98; 95% CI, 0.86 - 1.12; P = 0.66; I2 = 0%). LIMITATIONS: Inconsistent assessment tools and follow-up for chronic pain may contribute to the high heterogeneity and limitation of this analysis. CONCLUSIONS: We discovered that intravenous ketamine may reduce the incidence of CPSP in patients undergoing surgery, especially 3 - 6 months postsurgery. Because of the small sample size and high heterogeneity of the included studies, the effect of ketamine in the treatment of CPSP still needs to be explored in future large-sample, standardized-assessment studies.

How does the fiscal pressure of local governments affect China's PM2.5 emissions?

Affected by the epidemic and other factors, the global economy is in a downturn, and countries around the world are under unprecedented debt pressure. How will this affect environmental protection? Taking China as an example, this paper empirically studies the impact of changes in local government behavior on urban air quality under fiscal pressure. This paper uses the generalized method of moments (GMM) to find that fiscal pressure has significantly reduced PM2.5 emissions, with a unit increase in fiscal pressure will increase PM2.5 by about 2%. The mechanism verification shows that three channels affect PM2.5 emissions: (1) fiscal pressure has prompted local governments to relax the supervision of existing pollution-intensive enterprises. (2) Local governments reduce environmental regulations for attracting more pollution-intensive enterprises. (3) Local governments tend to reduce environmental protection investment to save fiscal expenses. The paper's conclusions provide new policy ideas for promoting environmental protection in China, as well as served as a case for analyzing current changes in environmental protection in other countries.

Esketamine combined with pregabalin on acute postoperative pain in patients undergoing resection of spinal neoplasms: study protocol for a randomized controlled trial.

BACKGROUND: Perioperative pain management is one of the most challenging issues for patients with spinal neoplasms. Inadequate postoperative analgesia usually leads to severe postsurgical pain, which could cause patients to suffer from many other related complications. Meanwhile, there is no appropriate analgesic strategy for patients with spinal neoplasms. METHODS/DESIGN: This is a protocol for a randomized double-blind controlled trial to evaluate the effect of esketamine combined with pregabalin on postsurgical pain in spinal surgery. Patients aged 18 to 65 years scheduled for spinal neoplasm resection will be randomly allocated into the combined and control groups in a 1:1 ratio. In the combined group, esketamine will be given during the during the surgery procedure until 48-h postoperative period, and pregabalin will be taken from 2 h before the surgery to 2 weeks postoperatively. The control group will receive normal saline and placebo capsules at the same time points. Both groups received a background analgesic regimen by using patient-controlled intravenous analgesia (containing 100 µg sufentanil and 16 mg ondansetron) until 2 days after surgery. To ensure the accuracy and reliability of this trial, all the researchers and patients will be blinded until the completion of this study. The primary outcome will be the proportion of patients with acute moderate-to-severe postsurgical pain (visual analog scale, VAS ≥ 40, range: 0-100, with 0, no pain; 100, the worst pain) during the 48-h postoperative period. The secondary outcomes will include the maximal VAS scores (when the patients felt the most intense pain over the last 24 h before being interviewed) at 0-2 h, 2-24 h, 24-48 h, and 48-72 h after leaving the operating room and 24 h before discharge; the incidence of acute moderate-to-severe postsurgical pain at each other time point; chronic postsurgical pain assessment; neuropathic pain assessment; and the incidence of drug-related adverse events and other postoperative complications, such as postoperative delirium and postoperative nausea and vomiting (PONV). DISCUSSION: The aim of this study was to evaluate the effect of esketamine combined with pregabalin on acute postsurgical pain in patients undergoing resection of spinal neoplasms. The safety of this perioperative pain management strategy will also be examined. TRIAL REGISTRATION: ClinicalTrials.gov NCT05096468. Registered on October 27, 2021.

Effect of esketamine on perioperative depressive symptoms in major surgery patients (PASSION II): study protocol for a randomised controlled trial.

INTRODUCTION: Depressive symptoms are common for patients undergoing major surgery and may worsen their mental health and lead to poor clinical outcomes. It is essential to seek a safe rapid-acting treatment for relieving moderate-to-severe depressive symptoms in patients undergoing major surgery. METHODS AND ANALYSIS: This study is a randomised, placebo-controlled and double-blinded trial aiming to determine the effect of esketamine on moderate-to-severe depressive symptoms in patients undergoing major surgery. Five hundred and sixty-four participants, aged 18-65 years old, undergoing major surgery will be randomly allocated into the esketamine and placebo groups at a 1:1 ratio. Esketamine or placebo will be given intravenously at the same speed on suturing the incision by anaesthesiologists in charge who are blinded to the randomisation. In the esketamine group, the total dosage of esketamine will be 0.2 mg/kg body weight. To estimate the efficacy and safety endpoints, blinded evaluation by trained researchers will be completed at 3 days, 5 days, 1 month, 3 months and 6 months after surgery. The primary outcome is the remission rate at the third postoperative day. The secondary outcomes include depression-related scores, severe pain events and safety-related endpoints such as psychotic symptoms, manic symptoms and dissociative symptoms. ETHICS AND DISSEMINATION: This study was approved by the Institutional Review Board of Beijing Tiantan Hospital, Capital Medical University, Beijing, China on 30 October 2020 (KY-2020-058-02). This trial is designed to explore whether the administration of esketamine could improve the mental health of patients with depressive symptoms undergoing major surgery. The conclusions of this study will be published in peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT04425473.

Effects of Intake Components and Stratification on the Particle and Gaseous Emissions of a Diesel Engine.

It is of great significance to improve the performance of diesel engines by adjusting the intake components and their distribution. In this work, various proportions of exhaust gas recirculation (EGR) gas and oxygen (O2) have been introduced to the intake charge of a diesel engine and the effects of different intake components and stratification conditions on pollutant emissions, especially for particles, have been explored. The results show that the introduction of O2 into the intake charge is beneficial to alleviate the deterioration of particles and hydrocarbon (HC) emissions caused by high EGR rates. Compared with the pure air intake condition, the introduction of moderate O2 at high EGR rate conditions can simultaneously reduce nitrogen oxides (NO x ) and particles, when the intake oxygen content (IOC) is 0.2 and the EGR rate is 20%, the NO x and particles are reduced by 45.66% and 66.49%, respectively. It is worth noting that different intake components have a significant impact on the particle size distribution (PSD) of diesel engines. In addition, the in-cylinder O2 concentration distribution formed by the stratified intake is advantageous for further improving the combined effect of NO x , particles and HC emissions relative to the homogeneous intake. At a condition of 0.2 IOC and 20% EGR rate, the NO x , particles, and HC emissions are about 8.8%, 14.3%, and 26% lower than that of intake components nonstratification, respectively.

Time point-dependent concordance and prognostic significance of flow cytometry and real time quantitative PCR for measurable/minimal residual disease detection in acute myeloid leukemia with t(8;21)(q22;q22.1).

BACKGROUND: Flow cytometry (FCM) and PCR are reliable methods for assessing minimal residual disease (MRD) in acute myeloid leukemia with t(8;21)(q22;q22.1). The aim of this study was to analyze the concordant rate of these two methods and their prognostic significance. METHODS: PCR and FCM were simultaneously used for MRD analysis at four different time points on 450 BM samples from 124 patients with AML with t(8;21)(q22;q22.1). The four monitoring time points included post-induction (first), after the first consolidation (second) and the second consolidation (third), and at the end of chemotherapy or before Allo/Auto stem cell transplantation (fourth). RESULTS: The concordant rates of the two methods were 33.06%, 25.81%, 49.59%, and 75.31%, respectively, and the main discordant cases were FCM-/PCR+ cases. At all monitoring time points, the MRD level ≥ 10-4 by FCM indicated a poor 3-year Relapse-Free Survival (RFS) (p < 0.001). More than 2-log MRD reduction by PCR after induction and more than 3-log reduction by PCR after the first consolidation remained the significant predictors of better RFS (p < 0.001). After the second consolidation, the negative MRD by PCR (<10-5) was also associated with improved RFS (p = 0.002). A > 1-log increase in PCR can effectively predict recurrence after molecular remission (p < 0.001). In the multivariate analysis, MRD≥0.01% by. FCM and less than 2-log MRD reduction by PCR after induction remained the significant predictors of poor RFS (p < 0.05). CONCLUSIONS: FCM+ always indicates a poor prognosis. Sequential monitoring by PCR is of significance for evaluating prognosis. Our findings suggest a complementary role of two analyses in optimizing risk stratification in clinical practice.

Dynamic reconfiguration of human brain networks across altered states of consciousness.

Consciousness is supported by rich neuronal dynamics to orchestrate behaviors and conscious processing can be disrupted by general anesthetics. Previous studies suggested that dynamic reconfiguration of large-scale functional network is critical for learning and higher-order cognitive function. During altered states of consciousness, how brain functional networks are dynamically changed and reconfigured at the whole-brain level is still unclear. To fill this gap, using multilayer network approach and functional magnetic resonance imaging (fMRI) data of 21 healthy subjects, we investigated the dynamic network reconfiguration in three different states of consciousness: wakefulness, dexmedetomidine-induced sedation, and recovery. Applying time-varying community detection algorithm, we constructed multilayer modularity networks to track and quantify dynamic interactions among brain areas that span time and space. We compared four high-level network features (i.e., switching, promiscuity, integration, and recruitment) derived from multilayer modularity across the three conditions. We found that sedation state is primarily characterized by increased switching rates as well as decreased integration, representing a whole-brain pattern with higher modular dynamics and more fragmented communication; such alteration can be mostly reversed after the recovery of consciousness. Thus, our work can provide additional insights to understand the modular network reconfiguration across different states of consciousness and may provide some clinical implications for disorders of consciousness.

Ketamine Alleviates Depressive Symptoms in Patients Undergoing Intracranial Tumor Resection: A Randomized Controlled Trial.

BACKGROUND: Depressive symptoms occur in over 40% of neurosurgical patients during the perioperative period. However, no measure has been suggested to have a rapid effect on depressive surgical patients during increasingly shorter stays in the hospital. This study aimed to determine whether ketamine could improve depressive symptoms rapidly and safely during the hospital stay. METHODS: This was a randomized, placebo-controlled, and double-blinded trial. Patients with moderate-to-severe depressive symptoms undergoing elective supratentorial brain tumor resection were randomized to intravenously receive either (1) 0.5 mg·kg-1 ketamine for 40 minutes or (2) an identical volume of normal saline. The primary outcome was treatment response on postoperative day 3, defined as a ≥50% reduction from the baseline depressive score. The secondary outcomes included the rate of remission and safety outcomes. The Montgomery-Åsberg Depression Rating Scale was applied by trained psychiatrists to evaluate depressive symptoms. RESULTS: A total of 84 neurosurgical patients were enrolled in the trial. The response rate was increased by the administration of ketamine (41.5% [17/41] vs 16.3% [7/43]; relative risk [RR]: 2.51, 95% confidence interval [CI], 1.18-5.50) relative to the administration of placebo at 3 days. Furthermore, the remission rate at discharge (29.3% [12/41] vs 7.0% [3/43]; RR: 4.20, 95% CI, 1.28-13.80) was also improved by ketamine. No psychotic symptoms or adverse events were reported to be substantially higher in the ketamine group. CONCLUSIONS: The trial indicates that the intraoperative administration of ketamine could alleviate moderate-to-severe depressive symptoms in neurosurgical patients without worsening safety.

Effects of Intake Components on Combustion and Emission Characteristics in an n-Butanol/Diesel Blend Fueled Engine.

To assess the effects of intake components and n-butanol application on compression-ignition engines, an experiment was carried out based on a single-cylinder engine fueled with n-butanol/diesel-blended fuel. The results show that with the increased n-butanol fraction of the blended fuel, the emissions of particulate mass (PM) decrease significantly, but the NO x and hydrocarbon (HC) emissions deteriorate. For B15 and B30, the PM emissions are 66.2% and 74.4% lower than B0, respectively. Furthermore, exhaust gas recirculation (EGR) was introduced to reduce the NO x emissions. However, a large EGR rate significantly reduces the indicated thermal efficiency (ITE) of the engine. Compared with the non-EGR condition, the ITE of B15 and B30 decrease by 3.1% and 3.8%, respectively, when the EGR rate is 18%. At the same time, the PM and HC emissions are found to be increased greatly. The PM emission of B15 and B30 increases by 69% and 46% and the HC emission increase by 150% and 71%, respectively. To restrain the engine emissions caused by the EGR, pure oxygen is further introduced into the intake charge. It is found that both the PM and HC emissions are significantly reduced with the introduction of extra oxygen. Under the condition of the 18% EGR rate, increasing oxygen addition to 4% can reduce HC emissions by more than 50% and the total particle mass of B15 and B30 is reduced by 60.6% and 47.7%, respectively. Moreover, the ITE reduction and combustion deterioration caused by the large EGR are found to be alleviated. By adjusting the n-butanol ratio, EGR rate, and oxygen addition, the excellent performance of combustion and emission can be achieved in an n-butanol/diesel blend fueled engine.

Subanesthetic Dose of Ketamine Improved CFA-induced Inflammatory Pain and Depression-like Behaviors Via Caveolin-1 in Mice.

BACKGROUND: Ketamine, a commonly used nonbarbiturate anesthetic drug, possesses antidepressant properties at subanesthetic doses; however, the underlying mechanisms remain unclear. MATERIALS AND METHODS: The analgesic and antidepressant effects of ketamine were explored using a complete Freund adjuvant (CFA)-induced peripheral inflammatory pain model in vivo. Mice were first divided into sham or CFA injection group randomly, and were observed for mechanical hyperalgesia, depression-like behavior, and mRNA expression of caveolin-1. Then ketamine was administered in CFA-treated mice at day 7. RESULTS: The behavioral testing results revealed mechanical hyperalgesia and depression in mice from days 7 to 21 after CFA injection. Ketamine reversed depression-like behaviors induced by CFA injection. It also restored the brain-regional expression levels of caveolin-1 in CFA-treated mice. In addition, caveolin-1 mRNA and protein expression were increased in the prefrontal cortex and nucleus accumbens of CFA-treated mice. However, ketamine reversed the increase in caveolin-1 expression in the ipsilateral and contralateral prefrontal cortex and nucleus accumbens, supporting the distinct roles of specific brain regions in the regulation of pain and depression-like behaviors. CONCLUSIONS: In CFA-treated mice that exhibited pain behavior and depression-like behavior, ketamine reversed depression-like behavior. The prefrontal cortex and nucleus accumbens are the important brain regions in this regulation network. Despite these findings, other molecules and their mechanisms in the signal pathway, as well as other regions of the brain in the pain matrix, require further exploration.

The immunophenotypic characteristics and flow cytometric scoring system of acute myeloid leukemia with t(8;21) (q22;q22); RUNX1-RUNX1T1.

INTRODUCTION: The translocation t(8;21) is one of the most frequent chromosome translocations in AML. Molecular (cyto)genetics is regarded as the gold standard for diagnosis. However, due to the complicated variety of AML-related genetic abnormalities, comprehensive screening for all of these abnormalities may not be cost-effective. Therefore, a flow cytometric (FC) scoring system was generated in this study for rapid screening and diagnosis of t(8;21)AML. METHODS: The immunophenotypic characteristics of leukemic cells and neutrophils in cases with t(8;21) AML or other subtypes of AML were analyzed to find a method for the flow diagnosis of t(8;21) AML. RESULTS: In this study, we picked six FC features pointing to the diagnosis of t(8;21) AML: The blasts show high-intensity expression of CD34; aberrant expression of CD19, cCD79a, and CD56 in myeloblasts; co-expression of CD56 in neutrophils, especially in immature neutrophils; and a maturity disturbance in granulocytes. A six-point score was devised using these features. By ROC analysis, the AUC was 0.952, and the sensitivity, specificity, PPV, and NPV were 0.86, 0.90. 0.91, and 0.84 when the score was ≥3 points. The score was then prospectively validated on an independent cohort, and the AUC of the ROC curve for the validation cohort was 0.975. When the cutoff value was set at 3, the obtained sensitivity and specificity values were 0.91 and 0.94, respectively. CONCLUSIONS: The FC score described can be used for the identification and rapid screening of t(8;21) AML.

Effect of low-dose ketamine on PerioperAtive depreSsive Symptoms in patients undergoing Intracranial tumOr resectioN (PASSION): study protocol for a randomized controlled trial.

BACKGROUND: Perioperative depressive symptoms (PDS) are common mental comorbidities that influence clinical outcomes and prognosis. However, there is no rapid-acting treatment to address these symptoms during a limited hospital stay. METHODS/DESIGN: This is a single-center, randomized, placebo-controlled, and double-blind trial. Randomization will be applied and stratified by the severity of PDS (moderate versus severe). Eighty patients who are scheduled for elective supratentorial brain tumor resection with PDS will be randomly allocated to the ketamine or placebo group with a ratio of 1 to 1. Patients in the ketamine group will be administered low-dose ketamine (0.5 mg/kg) intravenously for 40 min while the dural mater is being cut into, whereas patients in the placebo group will receive the same volume of normal saline at the same infusion rate at the same time points. The primary endpoint is the rate of PDS response at 3 days after surgery. Secondary outcomes include efficacy parameters such as the rate of PDS remission and safety outcomes such as the incidence of postoperative delirium, quality of recovery, and psychiatric side effects. DISCUSSION: This study aims to determine whether ketamine could improve the depressive symptoms of perioperative patients undergoing supratentorial brain tumor resection. It will also examine the safety of administering ketamine as an intraoperative anti-depressant. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03086148 . Registered on 22 March 2017.

[Clinical and laboratory investigation of patients with hematologic malignancies harboring der(1;7)(q10;p10)].

OBJECTIVE: To investigate the clinical and laboratory characteristics of patients with various hematological malignancies harboring der(1;7)(q10;p10). METHODS: Bone marrow samples were collected and undergone short-time unstimulated culture and R-banding, and karyotyped by conventional cytogenetic assay (CCA). Megalokaryocytes were detected by streptavidin-AKP (SAP). Retrospective analyses including the clinical and laboratory data were performed. RESULTS: Nineteen of the 21 patients were male. Most of the patients are of older age. Thirteen cases (61.9%) were der(1;7)(q10;p10) without additional aberrations, 8(38.1%) patients had additional aberrations. Sixteen out of the 18 cases (88.9%) who underwent SAP analysis had diminutive megalokaryocyte, and lymphoid megalokaryocyte was found in 10 cases (55.6%). The der(1;7) patients manifested poor response to treatment. CONCLUSION: The der(1;7) patients demonstrated distinct male predominance, older age at diagnosis, and some clinically distinctive features. These patients showed poor prognosis. The cytogenetic abnormality, i.e., der(1;7)(q10;p10), can be used as a prognostic indicator.