Longitudinal changes in body weight of breastfeeding mothers in the first year after delivery and its relationship with human milk composition:a combined longitudinal and cross-sectional cohort study

Objective:Postpartum weight retention(PPWR)is a common problem among women after childbirth.The main objectives of this study are to understand the changes in body weight of breastfeeding mothers during long-term follow-up and preliminarily explore the relationship between maternal body weight and human milk composition,including macronutrients,leptin,and adiponectin.Methods:The study included a longitudinal cohort(122 mothers),and a cross-sectional cohort(37 mothers).The human milk,maternal weight,and dietary surveys were collected in the longitudinal cohort at different follow-up time points(1-14 days postpartum,2-4 months postpartum,5-7 months postpartum,and 12-17 months postpartum).The maternal body weight was analyzed using the responses in the survey questionnaires.A milk analyzer based on the mid-infrared spectroscopy(MIRS)was used to determine milk composition,and nutrition analysis software evaluated dietary intakes.In the cross-sectional cohort,participating mothers were asked to provide blood and human milk samples and pertinent information related to maternal body composition.Maternal body composition was measured by bioelectrical impedance analysis(BIA),while ELISA analyzed leptin and adiponectin in milk and serum.Results:At 5-7 months postpartum,the PPWR of breastfeeding mothers was(2.46±3.59)kg.At 12-17 months postpartum,the PPWR was(0.98±4.06)kg.PPWR was found to be negatively correlated with milk fat content within 14 days postpartum and positively correlated at 2-4 months postpartum.In addition,the maternal weight and body muscle mass were positively correlated with leptin and adiponectin in milk.Plasma leptin was positively correlated with the mother’s body weight,body mass index(BMI),FAT percentage,and body fat mass,while plasma adiponectin did not correlate with any parameter.The results also indicate that the PPWR did not correlate with leptin and adiponectin in plasma or milk.Conclusions:Breastfeeding mothers may retain considerable weight gain one year after delivery.Human milk composition may be related to changes in maternal body weight.Leptin and adiponectin in breast milk and leptin in plasma are associated with the maternal body composition.This study supports the notion that maternal nutritional status may affect offspring health through lactation,and future research should focus on exploring weight management of postpartum mothers.

Intelligent In-Vehicle Safety System Based on Yolov5

In order to reduce the occurrence of traffic accidents and assist drivers to avoid dangerous driving. This paper presents a smart in-vehicle safety system that utilises the Yolov5 algorithm. Yolov5 algorithm is used to anticipate driver fatigue and distraction behaviours, and remind drivers to pay attention to safe driving in time. The system continuously splits the frames and analyses the frame content through the video feedback from the front camera, compared to the traditional machine learning, Yolov5’s mosaic data is enhanced, resulting in a batch size enhancement of 92.3%, and it also uses the Drop Block mechanism to prevent overfitting. The hardware of this system uses STM32 microcontroller and uses system DMA interrupt control and buzzer alarm device to warn about dangerous driving behaviour.

综合考虑尺寸和应变速率的单晶Ni_(3)Al屈服强度的理论模型

为了综合考虑尺寸和应变率效应对单晶延性材料屈服强度的影响,建立基于位错形核机制的理论模型。以Ni_(3)Al为例,首先,通过分子动力学模拟结果拟合出材料参数;然后,通过材料参数构建屈服强度的理论曲面;最后,用现有实验数据检验该理论模型。通过现有第三方单晶铜和金的分子动力学和实验数据对该模型进行检验。结果表明,该模型可以跨越分子动力学和实验条件之间巨大的空间和时间差异,从而得到单晶Ni_(3)Al、铜和金的可靠力学性能。

Spalling failure of deep hard rock caverns

Spalling is a typical brittle failure phenomenon of hard rock in deep caverns under high geostress.In this study,key issues are systematically studied concerning the spalling failure of deep hard rock caverns.First,the prismatic rock specimens with small thicknesses(i.e.width×thickness×height:20 mm×50 mm×100 mm)are employed in our tests which not only successfully simulate the spalling failure of hard rock in the laboratory but also obtain a reasonable spalling strength similar to that of the rock mass.Then,a series of spalling experiments is carried out to investigate the mechanism of spalling failure of deep hard rock caverns.Our results show that the intermediate principal stress,weak dynamic disturbances,and rock microstructure have significant effects on the spalling failure.The spalling strength is approximately(0.3–0.8)UCS,where UCS is the uniaxial compressive strength of the cylindrical rock sample with a diameter of around 50 mm.The spalling strength increases first and then decreases with increasing intermediate principal stress.Moreover,an empirical spalling strength criterion and a numerical method of spalling failure are proposed.This numerical method can not only simulate the spalling failure zone formed by tangential compressive stress concentration after excavation under different intermediate principal stresses,but also successfully simulate the failure transition from tensile mode to shear mode associated with confinement change in deep hard rock caverns.Furthermore,an acoustic emission-based early warning method using neural network is proposed to predict the spalling failure.Finally,a technical roadmap for preventing and controlling spalling failure of deep hard rock caverns is presented after summarizing the successful experiences in a typical engineering case.

Application of ablative therapy for intrahepatic recurrent hepatocellular carcinoma following hepatectomy

The post-hepatectomy recurrence rate of hepatocellular carcinoma(HCC)is persistently high,affecting the prognosis of patients.An effective therapeutic option is crucial for achieving long-term survival in patients with postoperative recurrences.Local ablative therapy has been established as a treatment option for resectable and unresectable HCCs,and it is also a feasible approach for recurrent HCC(RHCC)due to less trauma,shorter operation times,fewer complications,and faster recovery.This review focused on ablation techniques,description of potential candidates,and therapeutic and prognostic implications of ablation for guiding its application in treating intrahepatic RHCC.

直接前侧入路微创全髋关节置换术研究进展

全髋关节置换术(THA)常应用在髋关节疾病终末期的治疗中,其是采用人工材料制成仿真部件换取全髋组织的手术方式。尽管该术式手术创伤较大,存在一定风险,但其远期效果较好。THA有多种手术入路方式可供选取,直接前侧入路(DAA)自肌肉解剖间隙进入,可使髋关节充分显露,对肌肉组织损伤较小。现今医学界更加重视新型微创技术,相比于传统手术方式,DAA微创THA(MIS-THA)具有创伤小、疼痛轻、利于恢复的优点,但存在操作相对复杂、股外侧皮神经受损等不足。本文对DAA MIS-THA应用研究进展进行综述,以期指导临床实践。

The gut microbiome and intestinal failure-associated liver disease

Intestinal failure-associated liver disease(IFALD)is a common hepatobiliary complication resulting from long-term parenteral nutrition(PN)in patients with intestinal failure.The spectrum of IFALD ranges from cholestasis,steatosis,portal fibrosis,to cirrhosis.Development of IFALD is a multifactorial process,in which gut dysbiosis plays a critical role in its initiation and progression in conjunction with increased intestinal permeability,activation of hepatic immune responses,and administration of lipid emulsion.Gut microbiota manipulation including pre/probiotics,fecal microbiota transplantation,and antibiotics has been studied in IFALD with varying success.In this review,we summarize current knowledge on the taxonomic and functional changes of gut microbiota in preclinical and clinical studies of IFALD.We also review the function of microbial metabolites and associated signalings in the context of IFALD.By providing microbiota-targeted interventions aiming to optimize PN-induced liver injury,our review provides perspectives for future basic and translational investigations in the field.

Sandwich structured ultra-strong-heat-shielding aerogel/copper composite insulation board for safe lithium-ion batteries modules

The fire hazard of lithium-ion batteries(LIBs)modules is extremely serious due to their high capacity.Moreover,once a battery catches fire,it can easily result in a fire of the entire LIBs modules.In this work,a sandwich structure composite thermal insulation(STI)board(copper//silica dioxide aerogel//copper)with the advantages of low thermal conductivity(0.031 W m-1K-1),low surface radiation emissivity(0.1)and good thermal convection inhibition effect has been designed.The thermal runaway(TR)occurrence time of adjacent LIBs increases from 1384 s to more than 6 h+due to the protection of STI board.No TR propagation occurs within LIBs modules with protect of a STI board when a battery catches fire.The ultra-strong-heat-shielding mechanism of STI board has been revealed.The TR propagation of LIBs modules has been insulated effectively by STI board through reducing the heat transfer of convection,conduction and radiation.The air flow rate between the heater and LIBs and radiant heat absorbed by LIBs decrease by 63.5%and 35.1%with protection of STI board,respectively.A high temperature difference inside the STI board is also formed.This work provides direction for the designing of safe thermal insulation board for LIBs modules.

Facile modification of aluminum hypophosphate and its flame retardancy for polystyrene

A phosphorus-containing flame retardant, aluminum hypophosphite(AHPi), has been modified by(3-aminopropyl) triethoxysilane(KH550) to prepare flame-retardant polystyrene(PS). The influence of modified AHPi on the morphology and characterization was investigated, and differences in flame retardant properties of the PS/AHPi and PS/modified AHPi were compared. The PS composite can pass the vertical burning tests(UL-94 standard) with a V-0 rating when the mass content of modified AHPi reaches20%, compared with the mass content of 25% AHPi. The element mapping of the PS composite shows that modified AHPi has better dispersion in PS than AHPi. Thermogravimetric analysis results indicated that adding modified AHPi can advance the initial decomposition temperature of the composite material.With the addition of modified AHPi, the decrease in peak heat release rate(p HRR) is more evident than AHPi, and the char yield of the resultant PS composites gradually increased. With the addition of 25%modified AHPi, the p HRR and total heat release of PS composites decreased by 81.4% and 37.6%. The modification of AHPi promoted its dispersion in the PS matrix and improved the char formation of PS composites. The results of real-time infrared spectrometry of PS composites, Fourier transform infrared spectra and X-ray photoelectron analysis of the char layer indicated that modified AHPi has flame retardancy in condensed and gas phases.

Efficacy of ctDNA methylation combined with traditional detection modality to detect liver cancer among high-risk patients:A multicenter diagnostic trial

Objective:Circulating tumor DNA(ctDNA)and alpha-fetoprotein(AFP)plus ultrasound(US)have been considered to have high diagnostic accuracy for cancer detection,however,the efficacy of ctDNA methylation combined with the traditional detection modality of liver cancer has not been tested in a Chinese independent cohort.Methods:The high-risk individuals aged between 35 and 70 years who were diagnosed with liver cirrhosis or had moderate and severe fatty liver were eligible for inclusion.All participants were invited to receive a traditional examination[referring to AFP plus US],and ctDNA methylation,respectively.The sensitivity and specificity of different diagnostic tools were calculated.The logistic regression model was applied to estimate the area under the curve(AUC),which was further validated by 10-fold internal cross-validation.Results:A total of 1,205 individuals were recruited in our study,and 39 participants were diagnosed with liver cancer.The sensitivity of AFP,US,US plus AFP,and the combination of US,AFP,and ctDNA methylation was33.33%,56.41%,66.67%,and 87.18%,respectively.The corresponding specificity of AFP,US,US plus AFP,and the combination of all modalities was 98.20%,99.31%,97.68%,and 97.68%,respectively.The AUCs of AFP,US,US plus AFP,and the combination of AFP,US,and ctDNA methylation were 65.77%,77.86%,82.18%,and92.43%,respectively.The internally validated AUCs of AFP,US,US plus AFP,and the combination of AFP,US,and ctDNA methylation were 67.57%,83.26%,86.54%,and 93.35%,respectively.Conclusions:The ctDNA methylation is a good complementary to AFP and US for the detection of liver cancer.

Expert Consensus on Nutritional Support for Children with Congenital Heart Disease(2023 Edition)

The second edition of the expert consensus on pediatric nutrition was formed based on a global update of pedia-tric nutrition guidelines or consensus worldwide,the management of congenital heart disease,and the results of multi-center clinical nutrition research for congenital heart disease following thefirst Chinese consensus edition of 2016.The consensus was also shaped by the results of three discussion sessions and two questionnaires con-ducted by the 13-member collaboration group.This process was informed by both clinical guidelines and expert consensus.The quality of literature,both in English and Chinese,and the level of recommendations were evaluated using the Grading of Recommendations Assessment,Development,and Evaluations(GRADE)system.

Quality influencing factors of dispersion curves from short period dense arrays based on a convolutional neural network across the north section of the Xiaojiang fault area

The number of dispersion curves increases significantly when the scale of a short-period dense array increases.Owing to a substantial increase in data volume,it is important to quickly evaluate dispersion curve quality as well as select the available dispersion curve.Accordingly,this study quantitatively evaluated dispersion curve quality by training a convolutional neural network model for ambient noise tomography using a short-period dense array.The model can select high-quality dispersion curves that exhibit a≤10%difference between the results of manual screening and the proposed model.In addition,this study established a dispersion curve loss function by analyzing the quality of the dispersion curve and the corresponding influencing factors,thereby estimating the number of available dispersion curves for the existing observation systems.Furthermore,a Monte Carlo simulation experiment is used to illustrates the station-pair interval distance probability density function,which is independent of station number in the observational system with randomly deployed stations.The results suggested that the straight-line length should exceed 15 km to ensure that loss rate of dispersion curves remains<0.5,while maintaining the threshold ambient noise tomography accuracy within the study area.

Effect of Bio-Based Organic‒Inorganic Hybrid Hydrogels on Fire Prevention of Spontaneous Combustion of Coals

To solve the fire accidents caused by coal combustion,this work prepared four hybrid hydrogel materials using bio-based polymers,flame retardants,and inorganic materials.Compared to pure water and 3.5 wt%MgCl_(2)solution,the as-prepared hydrogel presents good fire prevention performance.In addition,it is found that CO and CO_(2)are not produced by coal when the pyrolysis temperature is lower than 200℃.During low-temperature pyrolysis,CO is more likely to be produced than CO_(2),indicating inadequate pyrolysis behavior.At the same time,the addition of fire-preventing hydrogel can not only decrease the maximum CO_(2)concentration before the critical temperature but also prolong the corresponding time.In addition,based on the cone calorimeter test,the inhibition effects of pure water,magnesium chloride solution,and four hybrid hydrogels on heat release behavior are evaluated.It is demonstrated that different dosages of different hydrogels affected the fire prevention effect.Phosphorous-modified cellulose/silica and carrageenan/DMMP/vermiculite composite hydrogels have the weakest fire prevention effect at 20 g,which is weaker than that of water.However,the fire prevention effect of carrageenan/DMMP/vermiculite composite hydrogels exceeded that of water at 40 and 60 g.Additionally,the fire prevention effect of the sodium alginate/sepiolite/ammonium polyphosphate composite hydrogel is most significant in common tests,attributed to the intumescent flame retardant system.

饱水和天然状态下页岩滞后效应及阻尼特性研究

运用RLW-2000型微机伺服岩石三轴试验机,对饱水状态和天然状态页岩在不同围压下进行三轴循环加卸载试验,分析了两种含水状态页岩的力学特性和滞后效应,并基于能量原理讨论了阻尼比演化规律。试验结果表明:随循环次数增加,累积残余应变逐渐增加,相对残余应变先降低,后趋于稳定区域,直至破坏前急剧增加;饱水页岩的加卸载变形模量均比天然页岩小,加载变形模量整体比卸载变形模量小;在加载和卸载阶段,均出现应变始终滞后于应力的现象;饱水页岩的滞后效应比天然页岩更明显。提出了考虑滞后效应的能量计算方法,较以往能量计算的误差更小。最后基于能量原理对阻尼比的计算公式进行修正,发现饱水页岩的阻尼比比天然页岩大。阻尼比的变化较好地反映了页岩损伤机制,可作为预判页岩失稳破坏的重要指标。

甘肃省金塔北海子国家湿地公园水鸟多样性调查初报

为探明甘肃金塔北海子国家湿地公园水鸟多样性现状,笔者于2017年8月、2017年11月和2018年4月,采用样带法调查了金塔北海子国家湿地公园水鸟的种群数量并进行多样性分析。调查共记录到水鸟31种,隶属于7目10科23属;秋季迁徙期水鸟的种群密度较大,形成规模较大的单优种群,但多样性和均匀度指数均小于其他季节;南北岸水鸟的群落构成和优势物种不尽相同且相似性指数不高。

某医院静脉用药调配中心不合理处方分析

目的分析某医院静脉用药调配中心不合理处方,不断提升医院合理用药水平。方法采用回顾性分析方法,从不合理处方的类型、科室分布、高警示药品、发现途径等方面,对安徽医科大学第二附属医院2015—2018年13876组不合理处方进行统计分析。结果总不合理处方占总处方的0.17%;溶媒规格不当是数量最多的类型,占总不合理处方数的47.64%;ICU是不合理处方数量最多的科室,占本科室总处方数的0.92%;高警示药品中非肠道和口服化疗药占比最高,占此类总处方数的0.53%;审方时发现的最多,占62.71%;干预成功率为99.85%。结论审方药师进行用药干预可有效降低不合理处方,提高静脉药物的合理用药水平。

Influence of dexamethasone on inflammatory mediators and NF-κB expression in multiple organs of rats with severe acute pancreatitis

AIM: To observe the therapeutic effects of dexamethasone on rats with severe acute pancreatitis (SAP) and investigate the influences of dexamethasone on the inflammatory mediators and NF-κB expression in multiple organs of SAP rats as well as the mechanisms involved. METHODS: Ninety Sprague-Dawley (SD) rats with SAP were randomly divided into the model group (n = 45) and dexamethasone treatment group (n = 45), and another 45 rats were selected for the sham operation group. All groups were randomly subdivided into the 3 h, 6 h and 12 h groups, each group containing 15 rats. The survival of all groups and pathological changes of multiple organs (liver, kidney and lung) were observed at different time points after the operation. The pathologicalscore of multiple organs was carried out, followed by the determination of amylase, endotoxin and TNF-α contents in blood. The tissue microarray was used to detect the expression levels of NF-κB p65 protein in multiple organs. RESULTS: There was no marked difference between the model group and treatment group in the survival rate. The amylase content of the treatment group was significantly lower compared to the model group at 12 h (P < 0.01, 7791.00 vs 9195.00). Moreover, the endotoxin and TNF-α levels of the treatment group were significantly lower than that of the model group at 6 h and 12 h (P < 0.01, 0.040 vs 0.055, 0.042 vs 0.059 and P < 0.05, 58.30 vs 77.54, 38.70 vs 67.30, respectively). Regarding the changes in liver NF-κB expression, the model group significantly exceeded the sham operation group at 3 h (P < 0.01, 1.00 vs 0.00), and the treatment group significantly exceeded the sham operation group at 12 h (P < 0.01, 1.00 vs 0.00), whereas no marked difference was observed between the model group and treatment group at all time points. The kidney NF-κB expression level in the treatment group significantly exceeded the model group (P < 0.05, 2.00 vs 0.00) and the sham operation group (P < 0.01, 2.00 vs 0.00) at 12 h. No NF-κB expression in the lung was found in any group. CONCLUSION: Dexamethasone can lower the amylase, endotoxin and TNF-α levels as well as mortality of SAP rats. NF-κB plays an important role in multiple organ injury. Further studies should be conducted to determine whether dexamethasone can ameliorate the pathological changes of multiple organs by reducing the NF-κB expression in the liver and kidney. The advantages of tissue microarrays in pancreatitis pathological examination include time- and energy- saving, and are highly efficient and representative. The restriction of tissue microarrays on the representation of tissues to various extents due to small diameter may lead to the deviation of analysis.

Disruption of interstitial cells of Cajal networks after massive small bowel resection

AIM: To investigate the disruptions of interstitial cells of Cajal (ICC) in the remaining bowel in rats after massive small bowel resection (mSBR). METHODS: Thirty male Sprague-Dawley rats fitting entry criteria were divided randomly into three experimental groups (n = 10 each): Group A rats underwent bowel transection and re-anastomosis (sham) and tissue samples were harvested at day 7 post-surgery. Group B and C rats underwent 80% small bowel resection with tissue harvested from Group B rats at day 7 post-surgery, and from Group C rats at day 14 postsurgery. The distribution of ICC at the site of the resid-ual small bowel was evaluated by immunohistochemical analysis of small intestine samples. The ultrastructural changes of ICC in the remnant ileum of model rats 7 and 14 d after mSBR were analyzed by transmission electron microscopy. Intracellular recordings of slow wave oscillations were used to evaluate electrical pacemaking. The protein expression of c-kit, ICC phenotypic markers, and membrane-bound stem cell factor (mSCF) in intestinal smooth muscle of each group were detected by Western blotting. RESULTS: After mSBR, immunohistochemical analysis indicated that the number of c-kit-positive cells was dramatically decreased in Group B rats compared with sham tissues. Significant ultrastructural changes in ICC with associated smooth muscle hypertrophy were also observed. Disordered spontaneous rhythmic contractions with reduced amplitude (8.5 ± 1.4 mV vs 24.8 ± 1.3 mV, P = 0.037) and increased slow wave frequency (39.5 ± 2.1 cycles/min vs 33.0 ± 1.3 cycles/min, P = 0.044) were found in the residual intestinal smooth muscle 7 d post mSBR. The contractile function and electrical activity of intestinal circular smooth muscle returned to normal levels at 14 d post mSBR (amplitude, 14.9 ± 1.6 mV vs 24.8 ± 1.3 mV; frequency, 30.7 ± 1.7 cycles/min vs 33.0 ± 1.3 cycles/min). The expression of Mscf and c-kit protein was decreased at 7 d (P = 0.026), but gradually returned to normal levels at 14 d. The ICC and associated neural networks were disrupted, which was associated with the phenotype alterations of ICC. CONCLUSION: Massive small bowel resection in rats triggered damage to ICC networks and decreased the number of ICC leading to disordered intestinal rhythmicity. The mSCF/c-kit signaling pathway plays a role in the regulation and maintenance of ICC phenotypes.

Evaluation of HCPTd_1, d_(14)-double passaged intervening chemotherapy protocol for hepatocellular carcinoma

AIM: To establish a kind of standardization of the clinical chemotherapeutic prototypes for unresectable hepatocellular carcinomas (HCC).METHODS: 10-Hydroxycamptothecin (HCPT) was applied through transcatheter arterial embolization (TAE) to HCC patients who were categorized into three groups: (1) test group: treatment with HCPT twice (HCPT d1 and 14) through TAE and portal venous embolization. (2) Control Ⅰ: treatment with anticancer drugs without HCPT. (3) Control Ⅱ: treatment with HCPT as a major component in anticancer drugs once (HCPT d1). A set of comparisons between test groups and control Ⅰ and Ⅱ groups were performed before and after the treatment to study the effectiveness of each treatment, in terms of tumor volumes, dynamic variations in serum alpha-fetoprotein (AFP), gamma-glutamyl transferase hepatoma-specific band (GGT-Ⅱ), patient survival and adverse events.RESULTS: The general effectiveness rate of the test group reached 62.1% (72/116), remarkably higher than that of control Ⅰ (32.1%, 40/124) and control Ⅱ (54.7%, 47/56),(P＜0.01 and P＜0.05, respectively). Especially, the reduction rate or disappearance of the portal vein tumor emboli was as high as 88.4% (61/69) in the test group, in contrast with 13.9% (10/72) in control Ⅰ and 35.9% (18/51) in control Ⅱ (P＜0.01 and P＜0.01, respectively). After treatment, AFP decreased or turned to negative levels at 52.3% (34/65)in control I, 67.3% (35/52) in control Ⅱ, and 96.8% (60/62)in the test group. Also GGT-Ⅱ declined or became negative at 37.8% (28/74) in control Ⅰ, 69.5% (57/82) in control Ⅱ,and 94.7% (89/94) in test group (P＜0.01 and P＜0.05,respectively).CONCLUSION: We have designed a good protocol (test group) to treat HCC with excellent advantages of high efficiency, low cost, low toxicity and low adverse events and easy application. It could be recommended as one of the standardizations for HCC treatment in clinical practice.

T-PBFT: An EigenTrust-Based Practical Byzantine Fault Tolerance Consensus Algorithm

Blockchain with these characteristics of decentralized structure, transparent and credible, time-series and immutability, has been considering as a promising technology. Consensus algorithm as one of the core techniques of blockchain directly affects the scalability of blockchain systems. Existing probabilistic finality blockchain consensus algorithms such as PoW, PoS, suffer from power consumptions and low efficiency;while absolute finality blockchain consensus algorithms such as PBFT, HoneyBadgerBFT, could not meet the scalability requirement in a largescale network. In this paper, we propose a novel optimized practical Byzantine fault tolerance consensus algorithm based on EigenTrust model, namely T-PBFT, which is a multi-stage consensus algorithm. It evaluates node trust by the transactions between nodes so that the high quality of nodes in the network will be selected to construct a consensus group. To reduce the probability of view change, we propose to replace a single primary node with a primary group. By group signature and mutual supervision, we can enhance the robustness of the primary group further. Finally, we analyze T-PBFT and compare it with the other Byzantine fault tolerant consensus algorithms. Theoretical analysis shows that our T-PBFT can optimize the Byzantine fault-tolerant rate,reduce the probability of view change and communication complexity.