Internal Heat Transfer Characteristics of Lamilloy Configurations

A transient measurement technique by using narrow-band thermochromic liquid crystal （TLC） is employed to determine temperature and heat transfer coefficient （HTC） distribution on inner surfaces of the typical lamilloy configurations. With this technique, both local HTC distribution and average HTC distribution could be obtained. The experimental results indicate that the variation of the porosity ratio, the one that the area of impingement holes divided by that of the plate, has a great effect on the HTC distribution on the inner surfaces. Heat exchange of inner surfaces varies directly as the porosity ratio. The impingement Reynolds number ranges from 20 000 to 50 000. The average HTC of inner surfaces bears a linear relationship with the Reynolds number.

The internal circulations on internal mass transfer rate of a single drop in nonlinear uniaxial extensional flow

The internal flow of a droplet in the nonlinear extensional flow field will exhibit more than two internal circulations with the variation of nonlinear intensity(E).In this paper,the effect of positions and sizes of internal circulations on internal mass transfer rate of a single spherical droplet in a nonlinear extensional flow field is studied and compared with that in a linear extensional flow field.The simulation results show that when E≥0,there are two symmetrical internal circulations in the droplet,which is the same with that in a linear extensional flow.The limit value of mass transfer rate Sh is 15,which is equal to that in a linear extensional flow,no matter how large E is.When E≤-3/7,the number of internal flow circulation of a droplet increase to four and the transfer rate Sh increases.When E=-1,the maximum internal transfer rate Sh equals 30 which is twice of that in a linear extensional flow.The generation of new flow circulations in droplets and the circulation positions will enhance mass transfer when E≤-3/7,which provides a new idea for enhancing the internal mass transfer rate of droplets.

Steady State Heat Transfer of Ladle Furnace During Steel Production Process

The heat transfer analysis was performed for an industrial ladle furnace （LF） with a capacity of 55-57 t in Turkey. The heat losses by conduction, convection and radiation from outer and bottom surfaces, top and electrodes of LF were determined in detail. Finally, some suggestions about decreasing heat losses were presented.

Genome-wide interrogation of transfer RNA-derived small RNAs in a mouse model of traumatic brain injury

Transfer RNA(t RNA)-derived small RNAs(ts RNAs) are a recently established family of regulatory small non-coding RNAs that modulate diverse biological processes. Growing evidence indicates that ts RNAs are involved in neurological disorders and play a role in the pathogenesis of neurodegenerative disease. However, whether ts RNAs are involved in traumatic brain injury-induced secondary injury remains poorly understood. In this study, a mouse controlled cortical impact model of traumatic brain injury was established, and integrated ts RNA and messenger RNA(m RNA) transcriptome sequencing were used. The results revealed that 103 ts RNAs were differentially expressed in the mouse model of traumatic brain injury at 72 hours, of which 56 ts RNAs were upregulated and 47 ts RNAs were downregulated. Based on micro RNA-like seed matching and Pearson correlation analysis, 57 differentially expressed ts RNA-m RNA interaction pairs were identified, including 29 ts RNAs and 26 m RNAs. Moreover, Gene Ontology annotation of target genes revealed that the significantly enriched terms were primarily associated with inflammation and synaptic function. Collectively, our findings suggest that ts RNAs may be associated with traumatic brain injury-induced secondary brain injury, and are thus a potential therapeutic target for traumatic brain injury. The study was approved by the Beijing Neurosurgical Institute Animal Care and Use Committee(approval No. 20190411) on April 11, 2019.

Inhibition of long non-coding RNA TUG1 on gastric cancer cell transference and invasion through regulating and controlling the expression of miR-144/c-Met axis

Objective: To discuss the expression of long noncoding RNA TUG1 (IneRNA-TUG1) in gastric carcinoma (GC) and its effects on the transferring and invading capacity of gastric carcinoma cells. Methods: Forty cases of carcinoma tissue and para-carcinoma tissue were selected from GC patients who underwent surgical removal in Zhejiang Provincial Hospital of Chinese Traditional Medicine and Wenzhou Central Hospital from January, 2013 to December, 2014; the expressing level of IncRNA-TUG I in GC and para-C tissues was detected by applying the qRT-PCR technique. The correlation between IncRNA-TUG1 expression and patients' clinical data was classified and analyzed. SGC-7901 cells were transfected using IncRNA-TUG1 specific siRNA. Changes of the transferring and invading capacity of siRNA-transfected SGC-7901 cells were scratch-tested and transwell-detected. qRT-PCR was applied to detect the expression level of microRNA-144 after IncRNA-TUG1 was silenced. Changes of c-Met mRNA and protein expressions was detected by qRT-PCR and western -blot test. Results: The expression level of lneRNA-TUG1 in GC tissue was significant higher than that in para-C tissue (P<0.05) and the high expression level of IncRNA-TUG1 in GC tissue was significantly correlated with tumor lymph nodes metastasis and advance TNM phasing (/'<0.05). The transferring and invading capacity of SGC-7901 cells was highly inhibited after being transfected by IncRNA-TUG1 specific siRNA (P<0.05). The results of qRT-PCR and western -blot proved that the expression of microRNA-144 was significantly boosted and the expression level of c-Met mRNA and protein was inhibited after IncRNA-TUG1 was silenced (P<0.05). Conclusions: IncRNA-TUG1 shows an up -regulated expression in GC tissue and that bears a correlation with clinicopathological features of malignant tumor. IncRNATUGI can promote the transferring and invading capacity of GC by inhibiting the pathway of microRNA-144/c-Met.

SIMULATION OF STEEL COIL HEAT TRANSFER IN HPH FURNACE

The mathematical model has been estublished for the simulation of steel coil＇s heat transfer during annealing thermal process in HPH （high performance hydrogen） furnace. The equivalent radial thermal conductivity is adopted by statistical analysis regression approach through the combination of a large quantity of production data collected in practice and theoretical analyses. The effect of the number of coils on circulating flow gas is considered for calculating the convection heat transfer coefficient, The temperature within the coil is predicted with the developed model during the annealing cycle including heating process and cooling process. The good consistently between the predicted results and the experimental data has demonstrated that the mathematical model established and the parameters identified by this paper are scientifically feasible and the effective method of calculation for coil equivalent radial heat transfer coefficient and circulating gas flow has been identified successfully, which largely enhances the operability and feasibility of the mathematic- model. This model provides a theoretical basis and an effective means to conduct studies on the impact that foresaid factors may imposed on the steel coil＇s temperature field, to analyze the stress within coils, to realize online control and optimal production and to increase facilily output by increasing heating and cooling rates of coils without producing higher thermal stress.

Transfer RNA-derived small RNA serves as potential non-invasive diagnostic marker and a novel therapeutic target for acute pancreatitis

Transfer RNA(tRNA)-derived fragments,a new type of tRNA-derived small RNA(tsRNA),can be cleaved from tRNA by enzymes to regulate target gene expression at the transcriptional and translational levels.tsRNAs are not only degradation fragments but also have biological functions,including those in immune inflammation,metabolic disorders,and cell death.tsRNA dysregulation is closely associated with multiple diseases,including various cancers and acute pancreatitis(AP).AP is a common gastrointestinal disease,and its incidence increases annually.AP development is associated with tsRNAs,which regulate cell injury and induce inflammation,especially pyroptosis and ferroptosis.Notably,serum tRF36 has the potential to serve as a non-invasive diagnostic biomarker and leads to pancreatic acinar cell ferroptosis causing inflammation to promote AP.We show the characteristics of tsRNAs and their diagnostic value and function in AP,and discuss the potential opportunities and challenges of using tsRNAs in clinical applications and research.

Zonal method solution of radiative heat transfer in a one-dimensional long roller-hearth furnace in CSP

A radiative heat transfer mathematical model for a one-dimensional long furnace was set up in a through-type roller-hearth furnace （TTRHF） in compact strip production （CSP）. To accurately predict the heat exchange in the furnace, modeling of the complex gas energy-balance equation in volume zones was considered, and the heat transfer model of heating slabs and wall lines was coupled with the radiative heat transfer model to identify the surface zonal temperature. With numerical simulation, the temperature fields of gas, slabs, and wall lines in the furnace under one typical working condition were carefully accounted and analyzed. The fundamental theory for analyzing the thermal process in TI＇RI-IF was provided.

The Earliest Discovery of the Role of Magnesium Ions on Stabilizing the Tertiary Structure of the Transfer RNA and Its Biological Significance —A Short Memoir

In early of 1960s, I was a graduate student studying on tRNA biochemistry. In the course of the research, the magnesium ions stabilized the tertiary structure of tRNA, resulting in its resistance to enzymatic degradation was discovered independently. The experiment of deaminated (denatured) tRNA obtained from native tRNA was designed and conducted and further proved the validity of this finding. It was found that magnesium ions could stabilize the tertiary structure of the natrive tRNA but could not stabilize structure of the deaminated tRNA. In term of the methodology, this stabilization technique has been widely applied in sequencing analysis of RNA and has greatly promoted the progress in the study of primary structure of RNA. More importantly, the stabilization of the tertiary structure of RNA by magnesium ions plays a key role both in the processing of messenger RNAs and the ribozyme activity. After our first article in Chinese was published in 1963, a paper of Nishimura & Novelli came into our note. The received date of their paper was March 22 of 1963, only 4 days earlier than that of our first paper. Thus, we and Nishimura & Novelli made almost at the same time the earliest discovery of the role of magnesium ions on stabilizing the tertiary structure of the transfer RNA and thus resulted in resistance of tRNA degradation by enzymes. However, this discovery was not initially appreciated for a period of time but was finally “visualized” and proved by X-ray crystal structure of yeast phenylalanine tRNA, which has provided more accurate information on the geometry of the magnesium-binding sites in tRNA.

Numerical simulation of aluminum holding furnace with fluid-solid coupled heat transfer

To predict three-dimensional temperature distribution of molten aluminum and its influencing factors inside an industrial aluminum holding furnace,a fluid-solid coupled method was presented.The fluid-solid coupled mathematics models of aluminum holding furnace in the premixed combustion processing were established based on mass conservation,moment conservation,momentum conservation,energy conservation and chemistry species conservation.Computational results agree well with the test data of the typical condition.The maximum combustion temperature is 1 850 K.The average temperature of the molten aluminum is 1 158 K,and the maximum temperature difference is about 240 K.The average temperature increases 0.3 ℃ while the temperature of combustion air increases 1 ℃.The optimal excess air ratio is 1.25-1.30.

Inter-species mRNA transfer among green peach aphids,dodder parasites,and cucumber host plants

mRNAs are transported within a plant through phloem.Aphids are phloem feeders and dodders(Cuscuta spp.)are parasites which establish phloem connections with host plants.When aphids feed on dodders,whether there is trafficking of mRNAs among aphids,dodders,and host plants and if aphid feeding a匚fects the mRNA transfer between dodders and hosts are unclear.We constructed a green peach aphid(GPA,Myzus persicae)-dodder(Cuscuta austra/is)-cucumber(Cucumis sativus)tritrophic system by infesting GPAs on C.australis,which parasitized cucumber hosts.We found that GPA feeding activated defense-related phytohormonal and transcriptomic responses in both C.australis and cucumbers and large numbers of mRNAs were found to be transferred between C.australis and cucumbers and between C.australis and GPAs;importantly,GPA feeding on C.australis greatly altered inter-species mobile mRNA profiles.Furthermore,three cucumber mRNAs and three GPA mRNAs could be respectively detected in GPAs and cucumbers.Moreover,our statistical analysis indicated that mRNAs with high abundances and long transcript lengths are likely to be mobile.This study reveals the existence of inter-species and even inter-kingdom mRNA movement among insects,parasitic plants,and parasite hosts,and suggests complex regulation of mRNA trafficking.

Mathematical model on heat transfer of water-cooling steel-stick bottom electrode of DC electric arc furnace

For predicting and controlling the melted depth of bottomelectrode during the process of steelmaking, the water-cooling steel-stick electrode is taken as an example, to analyze the process ofheat transfer, then 3D mathematical model by control capacity methodis built. At the same time, the measurement on the melted depth ofbottom electrode is conducted which verified the correctness of thebuilt mathematical model. On the base of verification, all kinds ofkey parameters are calculated through the application and a series ofresults are simulated. Finally, the optimum parameters are found andthe service life of bottom electrode is prolonged.

Experimental study of heat transfer of ultra-supercritical pressure water in vertical upward internally ribbed tube

Under ultra-supercritical pressure, the heat transfer characteristics of water in vertical upward 4- head internally ribbed tubes with a diameter of 28.65mm and thickness of 8mm were experimentally studied. The experiments were performed at P = 25- 34MPa, G = 450- 1800kg/（m^2·s） and q = 200 600kW/m^2. The results show that the pressure has only a moderate effect on the heat transfer of uhra-supercritical water when the water temperature is below the pseudocritical point. Sharp rise of the wall temperature near the pesudocritical region occurs earlier at a higher pressure. Increasing the mass velocity improves the heat transfer with a much stronger effect below the pesudocritical point than that above the pesudocritical point. For given pressure and mass velocity, the inner wall heat flux also shows a significant effect on the inner wall temperature, with a higher inner wall heat flux leading to a higher inner wall temperature. Increasing of inner wall heat flux leads to an early occurrence of sharp rise of the wall temperature. Correlations of heat transfer coefficients are also presented for vertical upward internally ribbed tubes.

External Heat Transfer in Moist Air and Superheated Steam for Softwood Drying

In kiln drying of softwood timber, external heat and moisture mass transfercoefficients are important in defining boundary temperature and moisture content at the woodsurface. In addition, superheated steam drying of wood is a promising technology but this has notbeen widely accepted commercially, partially due to the lack of understanding of the dryingphenomena occurred during drying. In this work, experimental investigation was performed to quantifythe heat transfer between wood surface and surrounding moist air or superheated steam. In theexperiment, saturated radiata pine sapwood samples were dried using dry-bulb/wet-bulb temperaturesof 60℃/50℃, 90℃/60℃, 120℃/70℃, 140℃/90℃, 160℃/90℃, 140℃/100℃ and 160℃/100℃. The lasttwo schedules were for superheated steam drying as the wet-bulb temperature was set at 100℃. Thecirculation velocity over the board surface was controlled at 4.2m·s^(-1). Two additional runs(90℃/60℃) using air velocities of 2.4 m·s^(-1) and 4.8 m·s^(-1) were performed to check theeffect of the circulation velocity. During drying, sample weight and temperatures at wood surfaceand different depths were continuously measured. Prom these measurements, changes in woodtemperature and moisture content were calculated and external heat-transfer coefficient wasdetermined for both the moist air and the superheated steam drying.

Calculations of Heat Transfer in Torch Furnaces by Gas Volume Radiation Laws

The results stemming from the calculation of heat transfer in torch furnaces by the laws, relating to radiation from solid surfaces and gas volumes are analyzed. The article presents the laws for radiation from gas volumes and the procedure for calculating heat transfer in torch furnaces, fire boxes, and combustion chambers, elaborated on their basis. The example of heat transfer calculation in a torch furnace is given, and it is significantly non-uniform in nature. Non-uniformity of heat flux distribution on heating surfaces is given. According to the results of calculations, a new furnace is designed to decrease the non-uniformity of ingot heating, fuel rate, and increase the furnace capacity. The calculation results of the distribution of heat fluxes on the heating surfaces are given in changing torch geometric dimensions. These results are confirmed by experimental studies.

Influence of Double-sided Delta-wing Tape Insert with Alternate-axes on Flow and Heat Transfer Characteristics in a Heat Exchanger Tube

The convective heat transfer and friction behaviors of turbulent tube flow through a straight tape with double-sided delta wings(T-W)have been studied experimentally.In the current work,the T-W formed on the tape was used as vortex generators for enhancing the heat transfer coefficient by breakdown of thermal boundary layer and by mixing of fluid flow in tubes.The T-W characteristics are(1)T-W with forward/backward-wing arrangement,(2)T-W with alternate axis(T-WA),(3)three wing-width ratios and(4)wing-pitch ratios.The experimental result reveals that for using the T-W,the increases in the mean Nusselt number(Nu)and friction factor are,respectively,up to 165%and 14.8 times of the plain tube and the maximum thermal performance factor is 1.19.It is also obvious that the T-W with forward-wing gives higher heat transfer rate than one with backward-wing around 7%. The present investigation also shows that the heat transfer rate and friction factor obtained from the T-WA is higher than that from the T-W.In addition,the flow pattern and temperature fields in the T-W tube with both backward and forward wings were also examined numerically.

结肠癌合并2型糖尿病患者血清lncRNA ANRIL、miR-181b-5p的表达及其与淋巴结转移的相关性

目的探讨结肠癌合并2型糖尿病(T2DM)患者血清长链非编码RNA INK4基因座中反义非编码RNA(lncRNA ANRIL)、微小RNA-181b-5p(miR-181b-5p)的表达及其与淋巴结转移的相关性。方法选取2019年5月—2022年8月本院收治的117例结肠癌合并T2DM患者为结肠癌合并T2DM组,并根据患者淋巴结转移情况将其分为淋巴结转移组56例和淋巴结未转移组61例。另选取同期体检的健康志愿者117例为对照组。采用反转录实时定量PCR检测血清lncRNA ANRIL、miR-181b-5p的相对表达水平。采用Logistic回归分析探讨影响结肠癌合并T2DM患者淋巴结转移的因素。绘制受试者工作特征(ROC)曲线分析血清lncRNA ANRIL、miR-181b-5p水平对结肠癌合并T2DM患者淋巴结转移的诊断价值。采用Pearson相关分析探讨结肠癌合并T2DM患者血清lncRNA ANRIL与miR-181b-5p表达的相关性。结果与对照组比较,结肠癌合并T2DM组患者血清lncRNA ANRIL水平升高,miR-181b-5p水平降低,差异均有统计学意义(P<0.01)。与淋巴结未转移组比较,淋巴结转移组患者血清lncRNA ANRIL水平升高,miR-181b-5p水平降低,差异均有统计学意义(P<0.01)。淋巴结转移组与淋巴结未转移组患者TNM分期、分化程度以及糖化血红蛋白(HbA1C)比较,差异有统计学意义(P<0.05)。糖尿病史、TNM分期、分化程度、HbA1C以及lncRNA ANRIL均是淋巴结转移的影响因素(P<0.05),miR-181b-5p是影响淋巴结转移的保护因素(P<0.05)。血清lncRNA ANRIL与miR-181b-5p水平呈负相关(r=-0.440,P<0.001)。ROC曲线结果显示,血清lncRNA ANRIL、miR-181b-5p以及二者联合诊断淋巴结转移的曲线下面积(AUC)分别为0.800、0.837、0.930,联合诊断价值显著高于lncRNA ANRIL(Z=2.956,P=0.003)、miR-181b-5p(Z=2.117,P=0.034)单独诊断价值。结论结肠癌合并T2DM患者血清lncRNA ANRIL水平升高,miR-181b-5p水平降低,且二者与淋巴结转移具有一定相关性。

Numerical modeling of multiphase flow,heat transfer and titanium flow behavior in blast furnace hearth

Understanding the complex phenomena in BF hearth is essential to increase furnace productivity and to extend furnace campaign.We have developed several continuum-based mathematical/numerical models to simulate the multi-phase flow,heat transfer and chemical reactions in the BF hearth.These models have generated an improved insight on the mechanisms for liquid drainage efficiency,lining erosion and wall protection in BF hearth under operational conditions.The current paper gives an overview of these studies in three aspects:Gas flow and pressure on the liquid surface,and their effect on the drainage characteristics;The flow and temperature distributions of liquid iron in BF hearth,and the temperature distribution in the refractories;Finally,titanium behaviors due to titania injection to form Ti(C,N) -rich scaffold on the hearth surface,to protect the hearth from erosion.

Heat transfer characteristics of thin power-law liquid films over horizontal stretching sheet with internal heating and variable thermal coefficient

The effect of internal heating source on the film momentum and thermal transport characteristic of thin finite power-law liquids over an accelerating unsteady horizontal stretched interface is studied. Unlike most classical works in this field, a general surface temperature distribution of the liquid film and the generalized Fourier＇s law for varying thermal conductivity are taken into consideration. Appropriate similarity transformations are used to convert the strongly nonlinear governing partial differential equations （PDEs） into a boundary value problem with a group of two-point ordinary differential equations （ODEs）. The correspondence between the liquid film thickness and the unsteadiness parameter is derived with the BVP4C program in MATLAB. Numerical solutions to the self-similarity ODEs are obtained using the shooting technique combined with a Runge-Kutta iteration program and Newton＇s scheme. The effects of the involved physical parameters on the fluid＇s horizontal velocity and temperature distribution are presented and discussed.

非编码RNA在肺纤维化过程中的调控作用

背景:截至目前,肺纤维化的发病机制不明,治疗手段或者药物有限。大量研究发现,非编码RNA在肺纤维化的发生发展过程中发挥重要作用。目的:综述近年来非编码RNA在肺纤维化发病机制中的调控作用,深入了解肺纤维化的发病机制。方法:由第一作者应用计算机检索2000-2024年出版的文献,以“非编码RNA,微小RNA,长链非编码RNA,环状RNA,肺纤维化,综述”等为中文检索词检索中国知网、万方和维普数据库;以“ncRNA,miRNA,lncRNA,circRNA,Pulmonary fibrosis,review”等为英文检索词检索PubMed数据库,按照入选标准最终共纳入65篇文献进行综述。结果与结论:肺纤维化作为一种慢性且通常致命的肺部疾病,不仅可能自发产生,也可能是其他疾病的继发结果,主要特点是肺部间质中细胞外基质的异常增生和大量积累。非编码RNA是指由基因组转录出来的RNA分子,这些RNA分子并不涉及蛋白质的编码过程,凭借其调节能力已成为各种生物学现象中的一线分子参与者之一。非编码RNA在肺纤维化的发病机制中扮演着关键角色,微小RNA(miRNA)、长链非编码RNA(lncRNA)和环状RNA(circRNA)可以通过影响基因表达、转录后修饰以及细胞间的信号传导,参与到肺纤维化的发展过程中,为后续探索肺纤维化疾病的具体分子发生机制提供了新方向,为研发肺纤维化疾病的新靶向药物提供了理论依据及新思路。