Long-term operation optimization of circulating cooling water systems under fouling conditions

Fouling caused by excess metal ions in hard water can negatively impact the performance of the circulating cooling water system(CCWS)by depositing ions on the heat exchanger's surface.Currently,the operation optimization of CCWS often prioritizes short-term flow velocity optimization for minimizing power consumption,without considering fouling.However,low flow velocity promotes fouling.Therefore,it's crucial to balance fouling and energy/water conservation for optimal CCWS long-term operation.This study proposes a mixed-integer nonlinear programming(MINLP)model to achieve this goal.The model considers fouling in the pipeline,dynamic concentration cycle,and variable frequency drive to optimize the synergy between heat transfer,pressure drop,and fouling.By optimizing the concentration cycle of the CCWS,water conservation and fouling control can be achieved.The model can obtain the optimal operating parameters for different operation intervals,including the number of pumps,frequency,and valve local resistance coefficient.Sensitivity experiments on cycle and environmental temperature reveal that as the cycle increases,the marginal benefits of energy/water conservation decrease.In periods with minimal impact on fouling rate,energy/water conservation can be achieved by increasing the cycle while maintaining a low fouling rate.Overall,the proposed model has significant energy/water saving effects and can comprehensively optimize the CCWS through its incorporation of fouling and cycle optimization.

Circulating tumor DNA and its role in detection, prognosis and therapeutics of hepatocellular carcinoma

Hepatocellular carcinoma(HCC) is considered the fifth most prevalent cancer among all types of cancers and has the third most morbidity value. It has the most frequent duplication time and a high recurrence rate. Recently, the most unique technique used is liquid biopsies, which carry many markers;the most prominent is circulating tumor DNA(ctDNA). Varied methods are used to investigate ctDNA, including various forms of polymerase chain reaction(PCR) [emulsion PCR(ePCR), digital PCR(dPCR), and bead, emulsion, amplification, magnetic(BEAMing) PCR]. Hence ctDNA is being recognized as a potential biomarker that permits early cancer detection,treatment monitoring, and predictive data on tumor burden are subjective to therapy or surgery. Numerous ctDNA biomarkers have been investigated based on their alterations such as 1) single nucleotide variations(either insertion or deletion of a nucleotide) markers including TP53, KRAS, and CCND1;2) copy number variations which include markers such as CDK6, EFGR, MYC and BRAF;3) DNA methylation(RASSF1A, SEPT9, KMT2C and CCNA2);4) homozygous mutation includes ctDNA markers as CDKN2A, AXIN1;and 5) gain or loss of function of the genes, particularly for HCC. Various researchers have conducted many studies and gotten fruitful results.Still, there are some drawbacks to ctDNA namely low quantity, fragment heterogeneity, less stability, limited mutant copies and standards, and differential sensitivity. However, plenty of investigations demonstrate ctDNA's significance as a polyvalent biomarker for cancer and can be viewed as a future diagnostic, prognostic and therapeutic agent. This article overviews many conditions in genetic changes linked to the onset and development of HCC, such as dysregulated signaling pathways, somatic mutations, single-nucleotide polymorphisms, and genomic instability. Additionally, efforts are also made to develop treatments for HCC that are molecularly targeted and to unravel some of the genetic pathways that facilitate its early identification.

Circulating tumor DNA in liquid biopsy: Current diagnostic limitation

With the rapid development of science and technology,cell-free DNA(cfDNA)is rapidly becoming an important biomarker for tumor diagnosis,monitoring and prognosis,and this cfDNA-based liquid biopsy technology has great potential to become an important part of precision medicine.cfDNA is the total amount of free DNA in the systemic circulation,including DNA fragments derived from tumor cells and all other somatic cells.Tumor cells release fragments of DNA into the bloodstream,and this source of cfDNA is called circulating tumor DNA(ctDNA).cfDNA detection has become a major focus in the field of tumor research in recent years,which provides a new opportunity for non-invasive diagnosis and prognosis of cancer.In this paper,we discuss the limitations of the study on the origin and dynamics analysis of ctDNA,and how to solve these problems in the future.Although the future faces major challenges,it also con-tains great potential.

Simulation of gas-solid flow characteristics of the circulating fluidized bed boiler under pure-oxygen combustion conditions

Under the pressure of carbon neutrality,many carbon capture,utilization and storage technologies have witnessed rapid development in the recent years,including oxy-fuel combustion(OFC)technology.However,the conventional OFC technology usually depends on the flue gas recirculation system,which faces significant investment,high energy consumption,and potential low-temperature corrosion problem.Considering these deficiencies,the direct utilization of pure oxygen to achieve particle fluidization and fuel combustion may reduce the overall energy consumption and CO_(2)-capture costs.In this paper,the fundamental structure of a self-designed 130 t·h^(-1) pure-oxygen combustion circulating fluidized bed(CFB)boiler was provided,and the computational particle fluid dynamics method was used to analyze the gas-solid flow characteristics of this new-concept boiler under different working conditions.The results indicate that through the careful selection of design or operational parameters,such as average bed-material size and fluidization velocity,the pure-oxygen combustion CFB system can maintain the ideal fluidization state,namely significant internal and external particle circulation.Besides,the contraction section of the boiler leads to the particle backflow in the lower furnace,resulting in the particle suspension concentration near the wall region being higher than that in the center region.Conversely,the upper furnace still retains the classic core-annulus flow structure.In addition to increasing solid circulation rate by reducing the average bed-material size,altering primary gas ratio and bed inventory can also exert varying degrees of influence on the gas-solid flow characteristics of the pure-oxygen combustion CFB boiler.

Experimental study on secondary air mixing along the bed height in a circulating fluidized bed with a multitracer-gas method

A multitracer-gas method was proposed to study the secondary air(SA)mixing along the bed height in a circulating fluidized bed(CFB)using carbon monoxide(CO),oxygen(O_(2)),and carbon dioxide(CO_(2))as tracer gases.Experiments were carried out on a cold CFB test rig with a cross-section of 0.42 m×0.73 m and a height of 5.50 m.The effects of superficial velocity,SA ratio,bed inventory,and particle diameter on the SA mixing were investigated.The results indicate that there are some differences in the measurement results obtained using different tracer gases,wherein the deviation between CO and CO_(2) ranges from 42%to 66%and that between O_(2) and CO_(2) ranges from 45%to 71%in the lower part of the fluidized bed.However,these differences became less pronounced as the bed height increased.Besides,the high solid concentration and fine particle diameter in the CFB may weaken the difference.The measurement results of different tracer gases show the same trends under the variation of operating parameters.Increasing superficial velocity and SA ratio and decreasing particle diameter result in better mixing of the SA.The effect of bed inventory on SA mixing is not monotonic.

Particle residence time distribution and axial dispersion coefficient in a pressurized circulating fluidized bed by using multiphase particle-in-cell simulation

The particle residence time distribution(RTD)and axial dispersion coefficient are key parameters for the design and operation of a pressurized circulating fluidized bed(PCFB).In this study,the effects of pressure(0.1-0.6 MPa),fluidizing gas velocity(2-7 m·s^(-1)),and solid circulation rate(10-90 kg·m^(-2)·s^(-1))on particle RTD and axial dispersion coefficient in a PCFB are numerically investigated based on the multiphase particle-in-cell(MP-PIC)method.The details of the gas-solid flow behaviors of PCFB are revealed.Based on the gas-solid flow pattern,the particles tend to move more orderly under elevated pressures.With an increase in either fluidizing gas velocity or solid circulation rate,the mean residence time of particles decreases while the axial dispersion coefficient increases.With an increase in pressure,the core-annulus flow is strengthened,which leads to a wider shape of the particle RTD curve and a larger mean particle residence time.The back-mixing of particles increases with increasing pressure,resulting in an increase in the axial dispersion coefficient.

Causal relationship between circulating vitamin C and 25-hydroxyvitamin D concentrations and common mental disorders-a Mendelian randomization study

Mental disorders seriously affect people’s health and social stability.This Mendelian randomization(MR)study was designed to investigate the causal relationship between circulating vitamin C(VC)or 25-hydroxyvitamin D(25(OH)D)levels and mental disorders.The data used for the MR analysis were derived from the summary genome-wide association studies(GWAS)database for VC and 25(OH)D and from the Finn Gen consortium for fourteen mental disorders.Based on the inverse variance weighted(IVW)method,we found a potential causal association between circulating VC and anxiety disorders(IVW:OR=1.139,95%CI:1.023-1.269,P=0.018).However,no causal association was found between VC or 25(OH)D and other mental disorders(P>0.05).In the reverse MR analysis,individuals with Alzheimer’s disease was causally associated with higher concentrations of circulating VC(P=0.012),while individuals with anxiety disorders had a negative association between the concentrations of 25(OH)D(P=0.012).However,the current evidence does not support a causal relationship between VC or 25(OH)D and other mental disorders.In addition,there was no causal association between circulating VC and 25(OH)D(P>0.05).Future studies are needed to confirm these findings and to elucidate the mechanisms of potential causality.

Prognostic value of circulating tumor cells combined with neutrophil-lymphocyte ratio in patients with hepatocellular carcinoma

BACKGROUND Circulating tumor cell(CTC)count and neutrophil-to-lymphocyte ratio(NLR)are both closely associated with the prognosis of hepatocellular carcinoma(HCC).AIM To investigate the prognostic value of combining these two indicators in HCC.METHODS Clinical data were collected from patients with advanced HCC who received im-mune therapy combined with targeted therapy at the Department of Oncology,the Affiliated Hospital of Southwest Medical University,Sichuan,China,from 2021 to 2023.The optimal cutoff values for CTC programmed death-ligand 1(PD-L1)(+)>1 or CTC PD-L1(+)≤1 and NLR>3.89 or NLR≤3.89 were evaluated using X-Tile software.Patients were categorized into three groups based on CTC PD-L1(+)counts and NLR:CTC-NLR(0),CTC-NLR(1),and CTC-NLR(2).The relationship between CTC-NLR and clinical variables as well as survival rates was assessed.RESULTS Patients with high CTC PD-L1(+)expression or NLR at baseline had shorter median progression-free survival(m-PFS)and median overall survival(mOS)than those with low levels of CTC PD-L1(+)or NLR(P<0.001).Mean-while,patients in the CTC-NLR(2)group showed a significant decrease in mPFS and mOS.Cox regression analysis revealed that alpha-fetoprotein(AFP),CTC PD-L1(+),and CTC-NLR were independent predictors of OS.The time-dependent receiver operating characteristic curve showed that the area under the curve of CTC-NLR at 12 months(0.821)and 18 months(0.821)was superior to that of AFP and CTC PD-L1(+).CONCLUSION HCC patients with high CTC PD-L1(+)or NLR expression tend to exhibit poor prognosis,and a high baseline CTC-NLR score may indicate low survival.CTC-NLR may serve as an effective prognostic indicator for patients with advanced HCC receiving immunotherapy combined with targeted therapy.

Development and validation of a circulating tumor DNA-based optimization-prediction model for short-term postoperative recurrence of endometrial cancer

BACKGROUND Endometrial cancer(EC)is a common gynecological malignancy that typically requires prompt surgical intervention;however,the advantage of surgical management is limited by the high postoperative recurrence rates and adverse outcomes.Previous studies have highlighted the prognostic potential of circulating tumor DNA(ctDNA)monitoring for minimal residual disease in patients with EC.AIM To develop and validate an optimized ctDNA-based model for predicting shortterm postoperative EC recurrence.METHODS We retrospectively analyzed 294 EC patients treated surgically from 2015-2019 to devise a short-term recurrence prediction model,which was validated on 143 EC patients operated between 2020 and 2021.Prognostic factors were identified using univariate Cox,Lasso,and multivariate Cox regressions.A nomogram was created to predict the 1,1.5,and 2-year recurrence-free survival(RFS).Model performance was assessed via receiver operating characteristic(ROC),calibration,and decision curve analyses(DCA),leading to a recurrence risk stratification system.RESULTS Based on the regression analysis and the nomogram created,patients with postoperative ctDNA-negativity,postoperative carcinoembryonic antigen 125(CA125)levels of<19 U/mL,and grade G1 tumors had improved RFS after surgery.The nomogram’s efficacy for recurrence prediction was confirmed through ROC analysis,calibration curves,and DCA methods,highlighting its high accuracy and clinical utility.Furthermore,using the nomogram,the patients were successfully classified into three risk subgroups.CONCLUSION The nomogram accurately predicted RFS after EC surgery at 1,1.5,and 2 years.This model will help clinicians personalize treatments,stratify risks,and enhance clinical outcomes for patients with EC.

A framework of force of information influence and application for C4KISR system

The subversive nature of information war lies not only in the information itself, but also in the circulation and application of information. It has always been a challenge to quantitatively analyze the function and effect of information flow through command, control, communications, computer, kill, intelligence,surveillance, reconnaissance (C4KISR) system. In this work, we propose a framework of force of information influence and the methods for calculating the force of information influence between C4KISR nodes of sensing, intelligence processing,decision making and fire attack. Specifically, the basic concept of force of information influence between nodes in C4KISR system is formally proposed and its mathematical definition is provided. Then, based on the information entropy theory, the model of force of information influence between C4KISR system nodes is constructed. Finally, the simulation experiments have been performed under an air defense and attack scenario. The experimental results show that, with the proposed force of information influence framework, we can effectively evaluate the contribution of information circulation through different C4KISR system nodes to the corresponding tasks. Our framework of force of information influence can also serve as an effective tool for the design and dynamic reconfiguration of C4KISR system architecture.

Arterial Duct Stenting Versus Modified Blalock-Taussig Shunt in Patient with Ductal-Dependent Pulmonary Circulation: Systematic Review & Meta-Analysis

Objective:Patients with ductal-dependent pulmonary circulation require alternative bloodflow to provide and maintain adequate oxygenation.Modified Blalock-Taussig Shunt(MBTS)has been the standard for providing such a result.Currently,less invasive methods such as Arterial Duct(AD)stenting have been performed as alter-natives.This study aims to compare the outcome of AD stenting and MBTS.Method:Systematic research was performed in online databases using the PRISMA protocol.The outcomes measured were 30-day mortality,com-plication,unplanned intervention,oxygen saturation,duration of hospital,and ICU length of stay.Any compara-tive study provided with full text is included.The outcome of each study was analyzed using a trandom effects model with relative risk and mean difference as the effect size.Bias risk assessment was conducted using the New-castle-Ottawa Scale.All analyses were performed using Review Manager 5.4.1.Result:A total of 11 studies with 3154 samples included in this study.There is no significant difference in 30-day mortality between the two groups(p-value=0.10).However,there is significantly less complication(RR 0.53[0.35,0.82];p-value=0.004)and unplanned intervention(RR 0.59[0.38,0.92];p-value=0.02)in the AD stent group.Comparison of the Nakata index showed no significant difference(p-value=0.88).Post-operative oxygen saturation was measured signifi-cantly higher in the AD stenting(MD 1.80[0.85,2.74];p-value=0.0002).However,AD stent group shows sig-nificantly lower long-term oxygen saturation(MD-8.43[-14.38,-2.48];p-value=0.005).Both hospital and ICU length of stay was significantly shorter in the AD stent group(MD-8.30[-11.13,-5.48];p-value<0.00001;MD-5.09[-7.79,-2.38];p-value=0.0002).Conclusion:AD stenting provides comparable outcomes relative to MBTS as it provides less complication and unplanned intervention and higher post-procedural O2 saturation.However,MBTS proved its superiority in maintaining higher long-term oxygen saturation and still became the preferred option to manage complex cases where stenting is either challenging or unsuccessful.

Circulating tumor cells as prognostic marker in pancreatic cancer

In this editorial we comment on the article by Zhang et al published in the recent issue of the World Journal of Clinical Oncology.Pancreatic cancer is the fourth most common cause of cancer-related mortality and has the lowest survival rate among all solid cancers.It causes 227000 deaths annually worldwide,and the 5-year survival rate is very low due to early metastasis,which is 4.6%.Cancer survival increases with better knowledge of risk factors and early and accurate diagnosis.Circulating tumor cells(CTCs)are tumor cells that intravasate from the primary tumor or metastasis foci into the peripheral blood circulation system spontan-eously or during surgical operations.Detection of CTC in blood is promising for early diagnosis.In addition,studies have associated high CTC levels with a more advanced stage,and more intensive treatments should be considered in cases with high CTC.In tumors that are considered radiologically resectable,it may be of critical importance in detecting occult metastases and preventing unnecessary surgeries.

Effect of Flow Directions on Multiphase Flow Boiling Heat Transfer Enhanced by Suspending Particles in a Circulating Evaporation System

A circulating fluidized bed evaporator(including down-flow, horizontal, and up-flow beds) was constructed to study the effect of flow directions on multiphase flow boiling heat transfer. A range of experimental investigations were carried out by varying amount of added particles(0-2%), circulation flow rate(2.15-5.16 m^3/h) and heat flux(8-16 kW/m^2). The comparison of heat transfer performance in different vertical heights of the horizontal bed was also discussed. Results reveal that the glass bead particle can enhance heat transfer compared with vapor-liquid two-phase flow for all beds. At a low heat flux(q = 8 kW/m), the heat-transfer-enhancing factor of the horizontal bed is obviously greater than those of the up-flow and down-flow beds. With the increase in the amount of added particles, the heat-transfer-enhancing factors of the up-flow and down-flow beds increase, whereas that of the horizontal bed initially increases and then decreases. However, at a high heat flux(q=16 kW/m), the heat-transfer-enhancing factors of the three beds show an increasing tendency with the increase in the amount of added particles and become closer than those at a low heat flux. For all beds, the heat-transfer-enhancing factor generally increases with the circulation flow rate but decreases with the increase in heat flux.

Optimization of circulating cooling water systems based on chance constrained programming

Recent research on deterministic methods for circulating cooling water systems optimization has been well developed. However, the actual operating conditions of the system are mostly variable, so the system obtained under deterministic conditions may not be stable and economical. This paper studies the optimization of circulating cooling water systems under uncertain circumstance. To improve the reliability of the system and reduce the water and energy consumption, the influence of different uncertain parameters is taken into consideration. The chance constrained programming method is used to build a model under uncertain conditions, where the confidence level indicates the degree of constraint violation. Probability distribution functions are used to describe the form of uncertain parameters. The objective is to minimize the total cost and obtain the optimal cooling network configuration simultaneously.An algorithm based on Monte Carlo method is proposed, and GAMS software is used to solve the mixed integer nonlinear programming model. A case is optimized to verify the validity of the model. Compared with the deterministic optimization method, the results show that when considering the different types of uncertain parameters, a system with better economy and reliability can be obtained(total cost can be reduced at least 2%).

Corrosion Inhibition by Co-Immobilized Lysozyme and Lipase in Circulating Cooling Water System

The corrosion inhibition performance of co-immobilized lysozyme and lipase was investigated in a recirculating cooling water system. Four methods were carried out in co-immobilization, and the operating parameters were optimized by using the respond surface methodology(RSM). The corrosion inhibition performance of co-immobilized lipase and lysozyme was evaluated by weight loss measurements and electrochemical measurements. The results revealed that the optimal co-immobilization method should be the sequential immobilization of lysozyme and then lipase. The inhibition efficiency was 86.10% under the optimal co-immobilized conditions. Electrochemical data showed that co-immobilized lysozyme and lipase was a mixed-type inhibitor and the corrosion inhibition efficiency was 81%.

Circulating Levels of Hypoxia-regulating MicroRNAs in Systemic Lupus Erythematosus Patients with Hemolytic Anemia

Objective MicroRNAs are fine regulators for gene expression during the post-transcriptional stage in many autoimmune diseases.HypoxamiRs(miR-210 and miR-21)play an important role in hypoxia and in inflammation-associated hypoxia.Systemic lupus erythematosus(SLE)is a chronic systemic autoimmune disease that would potentiate many pathological complications,including hemolytic anemia.This study aimed to investigate the role of hypoxamiRs in SLE/hemolytic anemia patients.Methods This work was designed to analyze the circulating levels of↱the miR-210 and miR-21 expressions and hypoxia-inducible factor-1α(HIF-α)in SLE/hemolytic anemia patients.SLE activity was evaluated for all patients by SLE Disease Activity Index(SLEDAI).Clinical manifestations/complications and serological/hematological investigations were reported.HIF-αconcentration was assayed by ELISA and expression of miR-21 and miR-210 was analyzed by qRT-PCR.Results The results indicated that the fold change of the miR-210/miR-21 expressions in plasma was significantly elevated in SLE/hemolytic anemia patients.A strong positive correlation between the miR-210 and miR-21 expression levels was also recorded.Among the associated-disease complications,hypertension,arthritis,oral ulcers,and serositis were associated with a high circulating miR-210 expression,while the occurrence of renal disorders was associated with the increased miR-21 expression.Furthermore,the HIF-αlevel was remarkably elevated in SLE/hemolytic anemia patients.A high positive correlation was recorded between the HIF-αconcentration and miR-210/miR-21 expression levels.The occurrence of oral ulcers,arthritis,and hypertension was associated with the increased HIF-αconcentration.On the other hand,SLEDAI and white blood cell count were positively correlated with miR-21/miR-210.The erythrocyte sedimentation rate was positively correlated with miR-21.Conclusion The dysregulation of the circulating miR-210/miR-210/HIF-1αlevels in SLE/hemolytic anemia patients advocated that the hypoxia pathway might have an essential role in the pathogenesis and complications of these diseases.

MIC in Circulating Cooling Water System

MIC is one of the main problems of circulating cooling water system. The direct economic loss by MIC is about 300 to 500 billion dollars. It is good to understand MIC in order to control MIC. Source and species of microorganisms was introduced firstly. There are three kinds of microorganisms in the system, including bacteria, fungi and algae. Species of these microorganisms are shown in the paper. Then, mechanisms of MIC are analysed. Although there is no universal mechanism of MIC, MIC is still mainly an electrochemical corrosion in nature. Meanwhile, the mechanisms on SRB and iron bacteria are introduced in details. At last, several methods of microorganisms control are put forward in the paper.

Circulating tumor cells and circulating tumor DNA in breast cancer diagnosis and monitoring

Liquid biopsy,including both circulating tumor cells and circulating tumor DNA,is becoming more popular as a diagnostic tool in the clinical management of breast cancer.Elevated concentrations of these biomarkers during cancer treatment may be used as markers for cancer progression as well as to understand the mechanisms underlying metastasis and treatment resistance.Thus,these circulating markers serve as tools for cancer assessing and monitoring through a simple,non-invasive blood draw.However,despite several study results currently noting a potential clinical impact of ctDNA mutation tracking,the method is not used clinically in cancer diagnosis among patients and more studies are required to confirm it.This review focuses on understanding circulating tumor biomarkers,especially in breast cancer.

Clinical outcomes of newly diagnosed primary central nervous system lymphoma treated with zanubrutinib-based combination therapy

BACKGROUND High-dose methotrexate(HD-MTX)combined with other chemotherapeutic agents is an effective treatment for patients with newly diagnosed primary central nervous system lymphoma(PCNSL);however,some patients have adverse reactions.AIM To retrospectively evaluate disease outcomes and mutational profiles in newly diagnosed PCNSL patients treated with a zanubrutinib/HD-MTX combination regimen.METHODS Nineteen newly diagnosed PCNSL patients were treated with zanubrutinib/HDMTX until disease progression,intolerable toxicities,or physician/patientdirected withdrawal.Safety and efficacy were assessed per the CTCAE v5.0 and RECIST v1.1 criteria,respectively.The primary endpoint was the objective response rate(ORR),and the secondary endpoints were progression-free survival,overall survival(OS),and safety.RESULTS The median follow-up duration was 14.7 mo(range,3.9–30 mo).The ORR for all patients was 84.2%,and 2-year progression-free-and OS rates were 75.6%and 94.1%,respectively.All patients completed the induction phase,and nine patients underwent autologous stem cell transplantation as consolidation therapy,resulting in an ORR of 88.9%.Ten patients received zanubrutinib as maintenance therapy and achieved an ORR of 80%.All patients showed an acceptable safety profile.The sequencing results for cerebrospinal fluid(CSF)and tumor tissue showed that PIM1 mutations were the most frequent genetic alterations.Circulating tumor DNA was correlated with disease relapse and response.CONCLUSION Our empirical observations demonstrated that the combination of zanubrutinib with HD-MTX yielded a marked clinical response and tolerability among newly diagnosed PCNSL patients.Non-invasive CSF liquid biopsy profiling may be feasible for evaluating treatment response and tumor burden.