肿瘤重症患者急性呼吸衰竭专家共识(2023版)

目的本共识的制定旨在为肿瘤重症患者合并呼吸衰竭的临床处理中常见问题提供基于临床证据的推荐意见。方法采用人群、干预、比较和预后(Population,Intervention,Comparison,and Outcome,PICO)原则对肿瘤重症患者呼吸衰竭的诊断和处理提出6个重要临床问题,基于文献检索和证据整合形成推荐意见。采用推荐意见分级评价、制定与评估(Grading of Recommendation Assessment,Development and Evaluation,GRADE)的方法讨论每个问题并经专家组讨论后形成共识意见。结果共识专家组形成了如下推荐意见。强推荐:(1)宏基因组二代测序可能有助于临床医师快速诊断合并呼吸衰竭的肿瘤重症患者的肺部感染;(2)体外膜肺(Extracorporeal Membrane Oxygenation,ECMO)不作为合并急性呼吸窘迫综合征的肿瘤重症患者常规挽救方案,多学科会诊后高选择性患者可能受益于ECMO治疗;(3)与标准化疗相比,免疫检查点抑制剂治疗增加肿瘤患者肺毒性的发生率;(4)接受机械通气的肿瘤患者如预计通气时间超过14天,早期气管切开可能使患者获益;(5)高流量氧疗和无创通气可以作为肿瘤合并呼吸衰竭的重症患者的一线氧疗方案。弱推荐:(6)对于癌肿压迫所致呼吸衰竭的肿瘤重症患者,如多学科会诊后考虑肿瘤对于药物潜在敏感,可采用紧急化疗作为挽救治疗。结论基于已有证据形成的推荐意见可指导肿瘤合并呼吸衰竭患者的诊断和治疗并改善预后。

Two acute kidney injury risk scores for critically ill cancer patients undergoing non-cardiac surgery

BACKGROUND:Several risk scoures have been used in predicting acute kidney injury(AKI)of patients undergoing general or specific operations such as cardiac surgery.This study aimed to evaluate the use of two AKI risk scores in patients who underwent non-cardiac surgery but required intensive care.METHODS:The clinical data of patients who had been admitted to ICU during the first 24 hours of ICU stay between September 2009 and August 2010 at the Cancer Institute,Chinese Academy of Medical Sciences & Peking Union Medical College were retrospectively collected and analyzed.AKI was diagnosed based on the acute kidney injury network(AKIN) criteria.Two AKI risk scores were calculated:Kheterpal and Abelha factors.RESULTS:The incidence of AKI was 10.3%.Patients who developed AKI had a increased ICU mortality of 10.9%vs.1.0%and an in-hospital mortality of 13.0 vs.1.5%,compared with those without AKI.There was a significant difference between the classification of Kheterpal's AKI risk scores and the occurrence of AKI(P<0.001).There was no significant difference between the number of Abelha's AKI risk scores and the occurrence of AKI(P=0.499).Receiver operating characteristic curves demonstrated an area under the curve of 0.655±0.043(P=0.001,95%confidence interval:0.571-0.739) for Kheterpal's AKI risk score and 0.507±0.044(P=0.879,95%confidence interval:0.422-0.592) for Abelha's AKI risk score.CONCLUSION:Kheterpal's AKI risk scores are more accurate than Abelha's AKI risk scores in predicting the occurrence of AKI in patients undergoing non-cardiac surgery with moderate predictive capability.

Effect of decarburization annealing temperature and time on the carbon content, microstructure, and texture of grain-oriented pure iron

In this study,the effect of decarburization annealing temperature and time on the carbon content,microstructure,and texture of grain-oriented pure iron was investigated by optical microscopy and scanning electron microscopy with electron-backscatter diffraction. The results showed that the efficiency of decarburization dramatically increased with increasing decarburization temperature. However,when the annealing temperature was increased to 825°C and 850°C,the steel's carbon content remained essentially unchanged at 0.002%. With increasing decarburization time,the steel's carbon content generally decreased. When both the decarburization temperature and time were increased further,the average grain size dramatically increased and the number of fine grains decreased; meanwhile,some relatively larger grains developed. The main texture types of the decarburized sheets were approximately the same: {001}<110> and {112~115}<110>,with a γ-fiber texture. Furthermore,little change was observed in the texture. Compared with the experimental sheets,the texture of the cold-rolled sheet was very scattered. The best average magnetic induction(B_(800)) among the final products was 1.946 T.

Sphingosine 1 phosphate receptor-1 （S1PR1） signaling protects cardiac function by inhibiting cardiomyocyte autophagy

ObjectiveTo 在 cardiomyocyte autophagy， cardiomyocyte 肥大和心脏的 function.MethodsCardiomyocytes 调查 sphingosine-1-phosphate (S1P ) 和它的受体的角色从新生的远景老鼠被孤立。分别地， cardiomyocytes 的 Autophagy 和肥大经由饥饿文化和 phenylephrine (PE ) 被导致， S1P 被用来对待 cardiomyocytes。cardiomyocyte autophagy 上的 S1P 的效果被 autophagosomes， autophagy 相关的蛋白质的表示和 autophagic 标记基因的数字在 cardiomyocytes 评估。cardiomyocyte 肥大上的 S1P 的效果被检验 cardiomyocytes 和 hypertrophic 基因的表示的表面区域评估。随后，不同小介入 RNA (siRNAs ) 习惯于击倒三的表示在 cardiomyocytes 上 S1P 受体打字，那调停分析受体的类型 S1P 在 cardiomyocytes 发信号。最后，鞘氨醇 1 磷酸盐 receptor-1 (S1PR1 ) 在用 Cas9 技术的老鼠 cardiomyocytes 是猛烈的。心脏的 autophagy 和心脏的肥大上的 S1PR1 的效果被估计 cardiomyocyte autophagy， cardiomyocyte 肥大和心脏的导致 function.ResultsStarvation 的 cardiomyocyte autophagy 检验，导致 PE 的 cardiomyocyte 肥大被 S1P 显著地稀释。结果证明 autophagosomes 的形成被减少，联系 autophagy 的蛋白质 LC3II/I 和 autophagic 标记基因 Atg5， Atg12， Beclin1 和 LC3B 的表示在 S1P 处理以后减少了。cardiomyocytes 的表面区域被减少，并且 hypertrophic 基因，包括的 atrial natriuretic 因素(ANF ) ，骨胳的肌肉和心脏的肌动朊(SKA ) 的表示，肌浆球蛋白重链(-MHC) 和大脑 natriuretic 肽(BNP ) 都在 S1P 处理以后被减少。在 S1PR1 组合式的组的 cardiomyocytes 的 autophagy 和肥大显著地在控制组， S1PR2 和 S1PR3 与那些相比被增加组合式的组。在 vivo，在 cardiomyocytes 的 S1PR1 的大美人加重了导致压力的心脏的 autophagy，心脏的肥大和心脏的 function.ConclusionS1P 的缺陷能禁止 cardiomyocyte autophagy，从而禁止 cardiomyocyte 肥大并且保护由激活在在鼠标的过载压力的 cardiomyocytes 的 S1PR1 的心脏的功能。

Association of the Common Genetic Variant Upstream of INSIG2 Gene with Obesity Related Phenotypes in Chinese Children and Adolescents

Objective To study the association between the rs7566605 variant of INSIG2 and obesity-related phenotypes in Chinese children and adolescents. Methods The study sample consisted of two independent cohorts of Chinese children and adolescents. Anthropometric indices, lipids, blood pressure, fasting glucose, insulin and percentage of fat mass were determined. PCR with restriction fragment length polymorphism analysis was performed for genotyping the rs7566605 variant. Results In each of the two independent cohorts, no significant association was observed between rs7566605 and obesity under additive, dominant or recessive model. We also did not detect any difference in the genotype frequency between all the obese children and controls. Furthermore, we did not find evidence of an association between body composition indices and metabolic phenotypes in all children. However, the triglyceride level of CC homozygotes was significantly higher than that of GG+GC genotypes in obese children (P=0.022). Additionally, we observed a non-significant trend of severe obesity in a post-hoc test. Conclusion INSIG2 rs7566605 variant is not associated Chinese childhood obesity in two independent cohorts. Further study is needed to verify the effect of rs7566605 on triglyceride in obese children.

Numerical study of AE and DRA methods in sandstone and granite in orthogonal loading directions

The directional dependency of the acoustic emission (AE) and deformation rate analysis (DRA) methods was analyzed, based on the contact bond model in the two-dimensional particle flow code (PFC2D) in two types of rocks, the coarse-grained sandstone and Aue granite. Each type of rocks had two shapes, the Brazilian disk and a square shape. The mechanical behaviors of the numerical model had already been verified to be in agreement with those of the physical specimens in previous research. Three loading protocols with different loading cycles in two orthogonal directions were specially designed in the numerical tests. The results show that no memory effect is observed in the second loading in the orthogonal direction. However, both the cumulative crack number of the second loading and the differential strain value at the inflection point are influenced by the first loading in the orthogonal direction.

Risk factors and prognosis of critically ill cancer patients with postoperative acute respiratory insufficiency

BACKGROUND:This study aimed to investigate the risk factors and outcome of critically ill cancer patients with postoperative acute respiratory insufficiency.METHODS:The data of 190 critically ill cancer patients with postoperative acute respiratory insufficiency were retrospectively reviewed.The data of 321 patients with no acute respiratory insufficiency as controls were also collected.Clinical variables of the first 24 hours after admission to intensive care unit were collected,including age,sex,comorbid disease,type of surgery,admission type,presence of shock,presence of acute kidney injury,presence of acute lung injury/acute respiratory distress syndrome,acute physiologic and chronic health evaluation(APACHE Ⅱ) score,sepsis-related organ failure assessment(SOFA),and PaO_2/FiO_2 ratio.Duration of mechanical ventilation,length of intensive care unit stay,intensive care unit death,length of hospitalization,hospital death and one-year survival were calculated.RESULTS:The incidence of acute respiratory insufficiency was 37.2%(190/321).Multivariate logistic analysis showed a history of chronic obstructive pulmonary diseases(P=0.001),surgeryrelated infection(P=0.004),hypo-volemic shock(P<0.001),and emergency surgery(P=0.018),were independent risk factors of postoperative acute respiratory insufficiency.Compared with the patients without acute respiratory insufficiency,the patients with acute respiratory insufficiency had a prolonged length of intensive care unit stay(P<0.001),a prolonged length of hospitalization(P=0.006),increased intensive care unit mortality(P=0.001),and hospital mortality(P<0.001).Septic shock was shown to be the only independent prognostic factor of intensive care unit death for the patients with acute respiratory insufficiency(P=0.029,RR:8.522,95%CI:1.243-58.437,B=2.143,SE=0.982,Wald=4.758).Compared with the patients without acute respiratory insufficiency,those with acute respiratory insufficiency had a shortened one-year survival rate(78.7%vs.97.1%,P<0.001).CONCLUSION:A history of chronic obstructive pulmonary diseases,surgery-related infection,hypovolemic shock and emergency surgery were risk factors of critically ill cancer patients with postoperative acute respiratory insufficiency.Septic shock was the only independent prognostic factor of intensive care unit death in patients with acute respiratory insufficiency.Compared with patients without acute respiratory insufficiency,those with acute respiratory insufficiency had adverse shortterm outcome and a decreased one-year survival rate.

Effect of sedation on short-term and long-term outcomes of critically ill patients with acute respiratory insufficiency

BACKGROUND: The present study aimed to determine the short-term and long-term outcomes of critically ill patients with acute respiratory insuffi ciency who had received sedation or no sedation.METHODS: The data of 91 patients who had received mechanical ventilation in the first 24 hours between November 2008 and October 2009 were retrospectively analyzed. These patients were divided into two groups: a sedation group(n=28) and a non-sedation group(n=63). The patients were also grouped in two groups: deep sedation group and daily interruption and /or light sedation group.RESULTS: Overall, the 91 patients who had received ventilation ≥48 hours were analyzed. Multivariate analysis demonstrated two independent risk factors for in-hospital death: sequential organ failure assessment score(P=0.019, RR 1.355, 95%CI 1.051–1.747, B=0.304, SE=0.130, Wald=50483) and sedation(P=0.041, RR 5.015, 95%CI 1.072–23.459, B=1.612, SE=0.787, Wald=4.195). Compared with the patients who had received no sedation, those who had received sedation had a longer duration of ventilation, a longer stay in intensive care unit and hospital, and an increased in-hospital mortality rate. The Kaplan-Meier method showed that patients who had received sedation had a lower 60-month survival rate than those who had received no sedation(76.7% vs. 88.9%, Log-rank test=3.630, P=0.057). Compared with the patients who had received deep sedation, those who had received daily interruption or light sedation showed a decreased in-hospital mortality rate(57.1% vs. 9.5%, P=0.008). The 60-month survival of the patients who had received deep sedation was signifi cantly lower than that of those who had daily interruption or light sedation(38.1% vs. 90.5%, Log-rank test=6.783, P=0.009).CONCLUSIONS: Sedation was associated with in-hospital death. The patients who had received sedation had a longer duration of ventilation, a longer stay in intensive care unit and in hospital, and an increased in-hospital mortality rate compared with the patients who did not receive sedation. Compared with daily interruption or light sedation, deep sedation increased the in-hospital mortality and decreased the 60-month survival for patients who had received sedation.

Prognosis of patients with shock receiving vasopressors

BACKGROUND:Consensus guidelines suggested that both dopamine and norepinephrine may be used,but specific doses are not recommended.The aim of this study is to determine the predictive role of vasopressors in patients with shock in intensive care unit.METHODS:One hundred and twenty-two patients,who had received vasopressors for 1 hour or more in intensive care unit(ICU) between October 2008 and October 2011,were included.There were 85 men and 37 women,with a median age of 65 years(55-73 years).Their clinical data were retrospectively collected and analyzed.RESULTS:The median simplified acute physiological score 3(SAPS 3) was 50(42-55).Multivariate analysis showed that septic shock(P=0.018,relative risk:4.094;95%confidential interval:1.274-13.156),SAPS 3 score at ICU admission(P=0.028,relative risk:1.079;95%confidential interval:1.008-1.155),and norepinephrine administration(P<0.001,relative risk:9.353;95%confidential interval:2.667-32.807) were independent predictors of ICU death.Receiver operating characteristic curve analysis demonstrated that administration of norepinephrine ≥0.7 μg/kg per minute resulted in a sensitivity of 75.9%and a specificity of 90.3%for the likelihood of ICU death.In patients who received norepinephrine ≥0.7 μg/kg per minute there was more ICU death(71.4%vs.44.8%) and in-hospital death(76.2%vs.48.3%) than in those who received norepinephrine <0.7 ug/kg per minute.These patients had also a decreased 510-day survival rate compared with those who received norepinephrine <0.7 μg/kg per minute(19.2%vs.64.2%).CONCLUSION:Septic shock,SAPS 3 score at ICU admission,and norepinephrine administration were independent predictors of ICU death for patients with shock.Patients who received norepinephrine ≥0.7 μg/kg per minute had an increased ICU mortality,an increased inhospital mortality,and a decreased 510-day survival rate.

Assessment of a predictive score for pulmonary complications in cancer patients after esophagectomy

BACKGROUND:Esophagectomy is a very important method for the treatment of resectable esophageal cancer,which carries a high rate of morbidity and mortality.This study was undertaken to assess the predictive score proposed by Ferguson et al for pulmonary complications after esophagectomy for patients with cancer.METHODS:The data of patients who admitted to the intensive care unit after transthoracic esophagectomy at Cancer Hospital of Chinese Academy of Medical Sciences and Peking Union Medical College between September 2008 and October 2010 were retrospectively reviewed.RESULTS:Two hundred and seventeen patients were analyzed and 129(59.4%)of them had postoperative pulmonary complications.Risk scores varied from 0 to 12 in all patients.The risk scores of patients with postoperative pulmonary complications were higher than those of patients without postoperative pulmonary complications(7.27±2.50 vs.6.82±2.67;P=0.203).There was no significant difference in the incidence of postoperative pulmonary complications as well as in the increase of risk scores(χ2=5.477,P=0.242).The area under the curve of predictive score was0.539±0.040(95%CI 0.461 to 0.618;P=0.324)in predicting the risk of pulmonary complications in patients after esophagectomy.CONCLUSION:In this study,the predictive power of the risk score proposed by Ferguson et al was poor in discriminating whether there were postoperative pulmonary complications after esophagectomy for cancer patients.

Phase Equilibria of Hydrogen Bonding Fluid in a Slit Pore with Broken Symmetry

液体与破对称在一个裂缝毛孔限制了的氢结合的阶段 equilibria (HB ) 被功能的理论与修改基本措施理论合并了的密度调查，在碎的对称从在液体分子和裂缝毛孔的二面墙之间的不同相互作用发源的地方。以吸附解吸附作用等温线和相应宏大潜力，在各种各样的条件下面的 HB 液体的阶段图被论述。通过放转变和毛状的冷凝作用的阶段共存，而且，阶段平衡性质上的 HB 相互作用，毛孔宽度，液体毛孔相互作用和破对称的效果被探讨。因为在分子间的相互作用和液体毛孔相互作用之间的比赛，这些因素能在限制 HB 液体的阶段 equilibria 上产生明显的影响，这被显示出。有趣地，裂缝毛孔的破对称的重要影响被发现，并且因此，碎的对称能提供一个新方法调整各种各样的限制液体的阶段行为。

Surface defects,stress evolution,and laser damage enhancement mechanism of fused silica under oxygen-enriched condition

Oxygen ions(O;)were implanted into fused silica at a fixed fluence of 1×10^(17) ions/cm^(2) with different ion energies ranging from 10 ke V to 60 ke V.The surface roughness,optical properties,mechanical properties and laser damage performance of fused silica were investigated to understand the effect of oxygen ion implantation on laser damage resistance of fused silica.The ion implantation accompanied with sputtering effect can passivate the sub-/surface defects to reduce the surface roughness and improve the surface quality slightly.The implanted oxygen ions can combine with the structural defects(ODCs and E′centers)to reduce the defect densities and compensate the loss of oxygen in fused silica surface under laser irradiation.Furthermore,oxygen ion implantation can reduce the Si-O-Si bond angle and densify the surface structure,thus introducing compressive stress in the surface to strengthen the surface of fused silica.Therefore,the laser induced damage threshold of fused silica increases and the damage growth coefficient decreases when ion energy up to30 ke V.However,at higher ion energy,the sputtering effect is weakened and implantation becomes dominant,which leads to the surface roughness increase slightly.In addition,excessive energy aggravates the breaking of Si-O bonds.At the same time,the density of structural defects increases and the compressive stress decreases.These will degrade the laser laser-damage resistance of fused silica.The results indicate that oxygen ion implantation with appropriate ion energy is helpful to improve the damage resistance capability of fused silica components.

Secondary coronary artery ostial lesions:Three case reports

BACKGROUND Atherosclerosis is one of the main causes of coronary artery ostial lesions seen clinically.Secondary coronary artery ostial lesions are rare,and cases reported previously were associated with syphilitic vasculitis and aortic dissection.Here,we report three rare cases of secondary coronary ostial lesions.Due to their rareness,these lesions can easily be neglected,which may lead to misdiagnosis and missed diagnosis.CASE SUMMARY We present three patients with acute myocardial infarction and unstable angina caused by secondary coronary artery ostial lesions.In Case 1,coronary angiography(CAG)revealed 90%stenosis of the left main coronary ostium.Chest contrast computed tomography(CT)suggested thymic carcinoma invading the left main coronary ostium.Coronary artery bypass grafting and tumor resection were performed.In Case 2,echocardiography revealed a sinus of Valsalva aneurysm(SVA)-like dilatation.CAG showed a right coronary sinus giant aneurysm and complete obstruction of the right coronary artery(RCA)ostium.Aortic contrast CT confirmed these findings.The Bentall procedure was performed.In Case 3,CT CAG identified an anomalous origin of the right coronary artery(AORCA)from the left sinus of Valsalva coursing between the aorta and pulmonary trunk,causing severe RCA ostium stenosis by compression.Surgical correction of the AORCA was performed.CONCLUSION The cases reported here suggest that we should consider other causes of coronary ostial lesions other than atherosclerosis.

Preventable readmission to intensive care unit in critically ill cancer patients

BACKGROUND:Readmission to intensive care unit(ICU)after discharge to ward has been reported to be associated with increased hospital mortality and longer length of stay(LOS).The objective of this study was to investigate whether ICU readmission are preventable in critically ill cancer patients.METHODS:Data of patients who readmitted to intensive care unit(ICU)at National Cancer Center/Cancer Hospital of Chinese Academy of Medical Sciences(CAMS)and Peking Union Medical College(PUMC)between January 2013 and November 2016 were retrospectively collected and reviewed.RESULTS:A total of 39 patients were included in the final analysis,and the overall readmission rate between 2013 and 2016 was 1.32%(39/2,961).Of 39 patients,32(82.1%)patients were judged as unpreventable and 7(17.9%)patients were preventable.There were no significant differences in duration of mechanical ventilation,ICU LOS,hospital LOS,ICU mortality and in-hospital mortality between patients who were unpreventable and preventable.For 24 early readmission patients,7(29.2%)patients were preventable and 17(70.8%)patients were unpreventable.Patients who were late readmission were all unpreventable.There was a trend that patients who were preventable had longer 1-year survival compared with patients who were unpreventable(100%vs.66.8%,log rank=1.668,P=0.196).CONCLUSION:Most readmission patients were unpreventable,and all preventable readmissions occurred in early period after discharge to ward.There were no significant differences in short term outcomes and 1-year survival in critically ill cancer patients whose readmissions were preventable or not.

Incidence and outcomes of secondary infections in septic patients with cancer

Secondary infections,also called intensive care unit(ICU)-acquired infections,are defi ned as infections occurring 48 h after admission to the ICU.[1]Critically ill patients are at a high risk of developing ventilator-associated pneumonia(VAP)and bloodstream infections(BSIs),which are associated with increased ICU mortality.

Scaling Transformation for Nonlocal Interactions

In the light of their relationships with renormalization, in this paper we associate the scaling transformation with nonlocal interactions. On one hand, the association leads us to interpret the nonlocality with locally symmetric method. On the other hand, we find that the nonlocal interaction between hadrons could be test ground for scaling transformation if ascribing the running effects in renormalization to scaling transformation. The nonlocal interaction Lagrangian turns out to vary under scaling transformation, analogous to running cases in renormalization. And the total Lagrangian becomes scale invariant only under some extreme conditions. The conservation law of this extreme Lagrangian is discussed and a contribution named scalum appears to the spin angular momentum. Finally a mechanism is designed to test the scaling effect on nonlocal interaction.

A New Method for Synthesizing Hyperbranched Polymers with Reductive Groups Using Redox/RAFT/SCVP

The novel hyperbranced polymers containing reductive groups were successfully prepared and characterized using redox/reversible addition fragmentation chain transfer(RAFT)/self-condensing vinyl polymerization(SCVP) method. Several redox initiating chemicals such as Cu(III)/―CONH2, Ce(IV)/―CONH2 and Ce(IV)/―OH were chosen to increase the free radical generating rate, and the chain transfer agent(CTA) was used to reduce the molecular chain propagating rate, in order to obtain polymers with high degree of branching. Detailed analyses based on the molecular weight, ? value and the degree of branching of polymers(DB) obtained from 1H-NMR spectra and multi detector size exclusion chromatography(MDSEC) suggested the acquiring of hyperbranced polyacrylamides with Cu(III)/―CONH2 and Ce(IV)/―CONH2 as initiator in the presence of the CTA. Meanwhile, the as-prepared poly(N-hydroxymethyl acrylamide)(PNHAM) with higher DB value(0.48) proved that using Ce(IV)/―OH as the initiator could increase the free radical generating rate and diminish the gap between the propagating rate and the initiation rate during the reaction procedure. In addition, the effect of oxidant concentration on the Mark-Houwink index(?) value and the DB was also studied.

Effects of Temperature and Alloying Elements on γ Phase Fraction of Grain-oriented Silicon Steel

The effects of temperature and alloying elements on γ phase fraction of grain-oriented silicon steel,which contained 2.97-3.42mass% Si and 0.028-0.058mass% C,were studied by microstructure observation and statistics.Furthermore,the quantitative relationships of temperature as well as C,Si,and Mn contents to γ phase fraction were obtained by numerical fitting.The experimental results show that γ phase fraction firstly increases with increasing temperature,reaches a maximum and then decreases in the temperature range of 900-1 250 ℃.The temperature corresponding to the maximum γ phase fraction is about 1 150-1 200℃.Meanwhile,the γ phase fractions in steels at the same temperature have some differences because of different contents of various alloying elements.The verification results show that the values of γ phase fractions to C,Si,and Mn contents at the specific temperatures,which were obtained by multiple linear regression method,agree well with the measured values.In addition,the values of γ phase fractions to C,Si,and Mn contents in the temperature range of 900-1 250℃,which were obtained by binomial regression method,agree with the measured values when the contents of Mn and soluble Al are not more than 0.320mass% and 0.034mass%,respectively.The obtained equations can carry out the approximate prediction of γ phase fractions of grain-oriented silicon steels during the hot rolling process.

Eutrophication: a limiting nutrient is not necessarily an abating factor

Eutrophication and algal blooms are a global environmental problem. In terms of nutrient control of eutrophic waters, there is still a heated debate on reducing P only or both P and N [1–3].The core question is whether algal communities are P-limited or N-limited or co-limited;the basic assumption is that limiting nutrients are those which should be reduced (2)But, is the assumption really true?The law of limiting factors (so-called Liebig’s Law of the Minimum) was first formed by Sprengel in 1828 in essence. He stated:

Characterizing microstructure and texture after recrystallization annealing of Hi-B steel with simutaneous decarburization and nitriding

How to manufacture the high magnetic induction grain-oriented silicon steel(Hi-B steel)by the process featured with the primary recrystallization annealing was demonstrated,during which nitriding and decarburizing were simultaneously realized in laboratory.By the techniques of optical microscope,scanning electronic microscope and electron backscattered diffraction,both the microstructure and the texture in the samples were characterized.The samples had been subjected to nitriding to different nitrogen contents at two specified temperatures using the two defined microstructural parameters:the grain size inhomogeneity factorσ*and the texture factor AR.The former is the ratio of the mean value to standard deviation of grain sizes;the latter is the ratio of the total volume fraction of the harmful textures to that of beneficial textures including {110}<001>.When the N content increased from 0.0055%to 0.0330%after the annealing at both 835 and 875°C,the resultant recrystallized grain size decreased butσ*changed little;whilst the rise of annealing temperature from 835 to 875°C resulted in the increase in both grain size andσ*.Moreover,either the injected N content or temperature had insignificant influence on the components of primary recrystallization texture developed during annealing.However,the increase of temperature led to the decreases in both intensity and volume fraction of{001}<120>and{110}<001>textures but increases in the{114}<481>andγfiber textures and the resultant decrease of AR.