Fast and Accurate Identification of <i>M. tuberculosis</i>Complex Using an Immunochromatographic MPT64 Antigen Detection Test

Background: A new rapid Immunochromatographic test (ICT) kit (MPT64 TB Ag Kit) for detection of MPT64 Antigen in M. tuberculosis (MTB) isolates used for rapid identification of MTB isolates developed by SD (Standard Diagnostics) Bio line, South Korea was evaluated. The ICT is a rapid, reliable and cheaper method that can be used instead of conventional biochemical tests for confirming MTB in culture isolates in resource limited laboratories. The study also evaluated the ability of ICT to detect MPT64-Antigen before the micro MGIT could signal positive. Material/Methods: A total of 450 sputum samples of individual patients were used for the study. 152 isolates of Mycobacteria were recovered from solid and liquid media. These strains were tested for the detection of MPT64-antigen. H37Rv strain was served as the positive reference control and also used for early detection of Antigen experiment. Findings: The development of bands on both test and sample region when H37Rv strain was tested were seen (MPT64 antigen positive). When 138 MTB isolates were tested, it showed a similar banding pattern indicating 100% sensitivity. MPT64 band formation was not detected in any of the 14 isolates indicating 100% specificity. Both PPV & NPV were 100%. All the isolates negative for MPT64 Ag were confirmed as MOTT by conventional bio-chemical PNBA. The H37Rv strain showed a faint band from the 2nd day onwards from inoculation till 3rd day in the earlier Antigen detection experiment. Conclusion: Rapid identification of MTB culture isolate is a pressing need for diagnosis and proceeding to perform drug susceptibility testing. MPT64 TB Ag detection ICT kit is a rapid, reliable method, good substitute for molecular identification methods, and conventional biochemical test which is time-consuming and technically demanding. The early detection of Antigen can be used as an effective tool in diagnosis.

Research on horizontal electromagnetic continuous casting of copper tube blanks

The effect of commercial frequency electromagnetic field on the solidification structure and mechanical propertiesof copper hollow blanks prepared by horizontal continuous casting method was investigated. The results show thatwhen the electromagnetic field is imposed, columnar grains are evidently refined and fine equiaxed grains areobtained in the inner side of the cross-section. Moreover, with the increase of input current, the equiaxed grain regionwidens and the grains distribute more uniformly in the circumferential direction. Meanwhile, the mechanical properties areremarkably improved by the application of electromagnetic field. When the input current is 140 A, the tensile strengthincreases 15% and the elongation increases 10%. However, the electromagnetic field has no effect on the distribution ofmicroelements.

Pipe reduction of miniature inner grooved copper tubes through rotary swaging process

A rotary swaging machine was applied to fabricating pipe reduction for miniature inner grooved copper tube （MIGCT） heat pipes. Compared with conventional swaging method, the axial feed of the designed rotary swaging machine was reached by a constant pushing force. The deformation of grooves in pipe reduced section during rotary swaging was analyzed. The shrinkage and extensibility of pipe reduction were measured and calculated. Furthermore, four aspects, including outer diameter, surface roughness, extensibility and processing time of pipe reduction, which were influenced by the pushing force, were considered. The results show that the tube wall thickness increases gradually along the z-axis at sinking section. However, the outer diameters, surface roughness and micro-cracks at reduced section tend to decrease along the z-axis. Besides, the effect of variation in the pushing force on the extensibility is limited while an increase in the pushing force results in a decrease of surface roughness. Therefore, a large pushing force within the limit is beneficial to pipe reduction manufacturing during rotary swaging process.

Compound forming technology of outside 3D integral fin of copper tubes

Using rolling-ploughing-extrusion compound processing methods,a 3D integral-fin structure on outside surface of red copper tube with diameter of 16.0 mm and wall thickness of 1.5 mm was obtained. When both rolling depth and ploughing-extrusion(P-E) depth were 0.2 mm,rotating speed was 50 r/min,feed speed was 0.16 mm/r,3D fin structures with height of 0.25 mm were gotten. Two different fin structures were obtained in grooves formed with rolling-ploughing-extrusion compound forming technology and observed by scanning electron microscope(SEM). One is the compound structure with V-shaped groove and U-shaped groove,and the other is the single structure with V-shaped grooves. Two kinds of groove structures obtained by rolling processing and ploughing extrusion processing are restricted together by groove interval and rolling depth,and pitch and P-E depth,respectively. Based on the analysis of interaction of rolling and P-E processing,it is found from the result that the outside 3D integral-fin can be achieved by rolling-ploughing-extrusion compound processing when single V-shaped groove structures are formed by both rolling and P-E processing.

Heat Transfer in Horizontal Copper Tube Heated by Electric Heating Process

Heat transfer from electrical and electronics component is essential for better performance of that electrical system,The maximum heat transfer from that system results long period durability.In most of the system base provided for equipments are very small and placed in a very complicated position.so heat transfer by forced convection is not easy for that purpose.The heat transfer by natural convection is the familiar technique used in electronics cooling;there is huge group of apparatus that lends itself to natural convection.This category consist of stand-alone correspondence such as modems and small computers having an array of printed circuit boards(PCB)accumulate within an area.Natural convection heat transfer in heated horizontal duct drive away heat from the interior surface is offered.The duct is open-ended and round in cross section.The test section is heated by provision of heating coils,where constant wall heat flux mentioned.Heat transfer experiment is carried out for channel of 50 mm.internal diameter and 4 mm thickness with length 600 mm.Ratios of length to diameter of the channel are taken as L/D=12.Wall heat fluxes maintained at q//=300 W/m2 to 3150 W/m2.A methodical investigational record for the local steady state natural convection heat transfer activities is obtained.The wall heating condition on local steady-state heat transfer phenomena are studied.The present experimental data is compared with the existing theoretical and experimental results for the cases of vertical smooth tubes.

Simple Measurement of Carbon Films on Copper Tubes and Their Effects on Corrosion

It has been reported that pitting corrosion in copper tubes occurs due to the effect of a carbon film produced by the influence of undergoing an oil and heat treatment. As a quantitative method for determining the residual carbon amount, it has been reported that the inner surface of a copper tube can be dissolved with a mixed acid to collect and analyze the adhering carbon;however, this method is dangerous and difficult. Therefore, two methods were examined as a simple quantitative method for obtaining the residual carbon amount using copper tubes with known residual carbon amounts. One method utilizes X-ray photoelectron spectroscopy (XPS), and the other method utilizes the potential difference between the carbon film-adhered surface and carbon film-removed surface. In regard to XPS measurement, a linear correlation was found between the spectral intensity of C and the residual carbon amount;therefore, XPS measurements were considered to be effective as a simple measurement method for the carbon film on the inner surface of a copper tube. In the evaluation method by measuring the corrosion potential, a correlation was observed between the potential difference ΔE and the residual carbon amount of the inner surface of the tube and the outer surface of the polished tube. It is considered possible to estimate the residual carbon amount from the prepared calibration curve. Through these studies, it is suggested that the carbon film was non-uniformly present on the surface of the copper tube. Therefore, the galvanic current was measured, and the effect of a non-uniform carbon film on corrosion behavior was investigated. As a result, in the measurement of galvanic current, the current flowed from the copper tube with a large amount of residual carbon (cathode) to the copper tube with a small amount of residual carbon (anode). In addition, the higher the area ratio of the carbon film was, the larger the galvanic current tended to be.

Ammonia corrosion analysis of copper tubes and experimental research on non-copper improvement for heat exchanger in power plant

Ammonia corrosion in copper tube will affect the safety of boiler running in power plant. Therefore, no copper in heating system has become a technical orientation in heat exchanger reconstruction, This paper analyzes the condition and mechanism of ammonia corrosion occurring in copper tube used in coal-fired power plants. Using a general steam condensation testing equipment only for horizontal single tube, with water vapor and water as working fluid, on two types of steel tube with 2-side enhancement heat transfer, namely, a spirally fluted tube and a ratchet tube with internal spiral groove （RISG tube） which was developed recently, a set of experimental tests are conducted to investigate the characteristics of heat transfer and hydromeehanics. In order to compare easily, both one copper smooth tube and one steel smooth tube are also used in the experiment. The experimental results, which get from single horizontal tube, show that the overall heat transfer coefficient of steel spirally fluted tube are improved by 10%o to 17%, and that of the steel RISG tube（22%-28%） is better than steel spirally fluted tube, its flow resistance coefficient is only increased by 22% to 66% when compared with smooth tube. Based on a lot of experimental data, the steel spirally fluted tube and the steel RISG tube were applied in a low pressure preheater and an oil-cooler of some or other power plant respectively. The field testing results showed that their heat transfer coefficient with each types of enhancement heat transfer tubes were improved by 2.5% and 21%-45% comparing with copper smooth tube heat exchangers. Both basic and field experiment indicates that the steel tube with 2-side enhancement heat transfer is an ideal choice for heat exchanger reconstruction in no copper issue in power plants.

Microstructure and properties of TP2 copper tube with La microalloying by horizontal continuous casting

The TP2 copper tube was prepared with La microalloying by horizontal continuous casting(HCC). The absorptivity of La and its effects on microstructure, tensile and corrosion properties of HCC TP2 copper tube were studied by means of the inductively coupled plasma optical emission spectrometer(ICP-OES), optical microscope(OM), scanning electron microscope(SEM) and potentiodynamic polarization measurements. The results show that the absorptivity of La in the HCC TP2 copper tube is about 15% under antivacuum conditions due to the good chemical activities of La. The impurity elements in copper tube such as O, S, Pb and Si can be significantly reduced, and the average columnar dendrite spacing of the copper tube can also be reduced from 2.21 mm to 0.93 mm by adding La. The ultimate tensile strength and the elongation with and without La addition are almost unchanged. However, the annual corrosion rate of the HCC TP2 copper tube is reduced from 10.18 mm·a^(-1) to 9.37 mm·a^(-1) by the purification effect of trace La.

Macrostructure and properties of thin walled copper tubes prepared by the downward continuous unidirectional solidification method

The macrostructure and properties of the thin walled copper tube prepared by the downward continuous unidirectional solidification （DCUS） method were studied. The result shows that the macrostructure is closely related to the solid-liquid interface profile, which is influenced by the distance between the cooling water location and the solidification front. The mechanical properties of the thin walled copper tube prepared by the DCUS method are near those of the normal cast copper, and it has good relative density, electrical conductivity, and elongation, which are not greatly affected by casting speed. The thin walled copper tube prepared by the DCUS method also has good processing properties that can be taken to further drawing procedures directly without an intermediate process, and obtains good mechanical properties with the total processing rate of 89.8%.

Copper homeostasis and neurodegenerative diseases

Copper,one of the most prolific transition metals in the body,is required for normal brain physiological activity and allows various functions to work normally through its range of concentrations.Copper homeostasis is meticulously maintained through a complex network of copper-dependent proteins,including copper transporters(CTR1 and CTR2),the two copper ion transporters the Cu-transporting ATPase 1(ATP7A)and Cu-transporting beta(ATP7B),and the three copper chaperones ATOX1,CCS,and COX17.Disruptions in copper homeostasis can lead to either the deficiency or accumulation of copper in brain tissue.Emerging evidence suggests that abnormal copper metabolism or copper binding to various proteins,including ceruloplasmin and metallothionein,is involved in the pathogenesis of neurodegenerative disorders.However,the exact mechanisms underlying these processes are not known.Copper is a potent oxidant that increases reactive oxygen species production and promotes oxidative stress.Elevated reactive oxygen species levels may further compromise mitochondrial integrity and cause mitochondrial dysfunction.Reactive oxygen species serve as key signaling molecules in copper-induced neuroinflammation,with elevated levels activating several critical inflammatory pathways.Additionally,copper can bind aberrantly to several neuronal proteins,including alphasynuclein,tau,superoxide dismutase 1,and huntingtin,thereby inducing neurotoxicity and ultimately cell death.This study focuses on the latest literature evaluating the role of copper in neurodegenerative diseases,with a particular focus on copper-containing metalloenzymes and copper-binding proteins in the regulation of copper homeostasis and their involvement in neurodegenerative disease pathogenesis.By synthesizing the current findings on the functions of copper in oxidative stress,neuroinflammation,mitochondrial dysfunction,and protein misfolding,we aim to elucidate the mechanisms by which copper contributes to a wide range of hereditary and neuronal disorders,such as Wilson's disease,Menkes'disease,Alzheimer's disease,Parkinson's disease,amyotrophic lateral sclerosis,Huntington's disease,and multiple sclerosis.Potential clinically significant therapeutic targets,including superoxide dismutase 1,D-penicillamine,and 5,7-dichloro-2-[(dimethylamino)methyl]-8-hydroxyquinoline,along with their associated therapeutic agents,are further discussed.Ultimately,we collate evidence that copper homeostasis may function in the underlying etiology of several neurodegenerative diseases and offer novel insights into the potential prevention and treatment of these diseases based on copper homeostasis.

A Study of Water Treatment Chemical Effects on Type I” Pitting Corrosion of Copper Tubes

It is known that one of the causes of pitting corrosion of copper tubes is residual carbon on the inner surface. It was confirmed that type I” pitting corrosion of the copper tube is suppressed by keeping the residual carbon amount at 2 mg/m2 or less, which is lower than that of the type I’ pitting corrosion, or by removing the fine particles that are the corrosion product of galvanized steel pipes. The developed water treatment chemical was evaluated using three types of copper tubes with residual carbon amounts of 0 mg/m2, 0.5 mg/m2, and 6.1 mg/m2. The evaluation was conducted for three months in an open-circulation cooling water system and compared with the current water treatment chemical. Under the current water treatment chemical conditions, only the copper tube with a residual carbon amount of 6.1 mg/m2 showed a significant increase in the natural corrosion potential after two weeks, and pitting corrosion occurred. No pitting corrosion and no increase in the natural corrosion potential were observed in any of the copper tubes that were treated with the developed water treatment chemical. In addition, the polarization curve was measured using the cooling water from this field test, and the anodic polarization of two cooling waters was compared. For copper tubes with a large amount of residual carbon, the current density near 0 mV vs. Ag/AgCl electrode (SSE) increased when the developed water treatment chemical was added.

Evolution of Goss texture in thin-walled copper tube at different heat treatment temperatures

The evolution of microstructure,textures,and mechanical properties of thin-walled copper tube during heat treatment was investigated using EBSD technique and tensile test.The results show that the initial deformation textures of pre-drawn thin-walled copper tube are mainly composed of Copper and Y components,while with the increase of temperatures,the textures are transformed into a strong Goss texture gradually.The high-resolution microstructural characterizations indicate that the new Goss recrystallized grains nucleate and grow up within the deformed Copper grains and Y grains in different mechanisms,respectively.The tensile strength of the thin-walled copper tube decreases gradually with the increase of the temperature,while the elongation increases first and then decreases sharply due to the action of grain sizes and texture components.

Spatiotemporal expression of leukemia inhibitory factor receptor protein during neural tube development in embryos with neural tube defects

Leukemia inhibitory factor receptor(LIFR),as a neuroregulatory cytokine receptor,generally shows a neuroprotective effect in central nervous system injuries.In this study,to understand the effect of LIFR on pathogenesis of neural tube defects,we explored spatiotemporal expression of LIFR at different stages of fetal development in normal and neural tube defect embryos.Spina bifida aperta was induced with all-trans retinoic acid on embryonic day 10 in rats,and the spatiotemporal expression of LIFR was investigated in spina bifida aperta rats and healthy rats from embryonic day 11 to 17.Real time-polymerase chain reaction and western blot assay were used to examine mRNA and protein expression of LIFR in healthy control and neural tube defect embryos.Results of the animal experiment demonstrated that expression of LIFR protein and mRNA in the spinal cords of normal rat embryos increased with embryonic development.LIFR was significantly downregulated in the spinal cords of spina bifida aperta rats compared with healthy rats from embryonic days 11 to 17.Immunohistochemical staining showed that the expression of LIFR in placenta and spinal cord in spina bifida aperta rat embryos was decreased compared with that in control embryos at embryonic day 15.Results from human embryo specimens showed that LIFR mRNA expression was significantly down-regulated in spinal cords of human fetuses with neural tube defects compared with normal controls at a gestational age of 24 to 33 weeks.The results were consistent with the down-regulation of LIFR in the animal experiments.Our study revealed spatiotemporal changes in expression of LIFR during embryonic neurulation.Thus,LIFR might play a specific role in neural tube development.All animal and human experimental procedures were approved by the Medical Ethics Committee of Shengjing Hospital of China Medical University,China(approval No.2016PS106K)on February 25,2016.

Balloon dilation of Eustachian tube combined with tympanostomy tube insertion and middle ear pressure equalization therapy for recurrent secretory otitis media

Objective: To report outcomes of balloon dilation Eustachian tuboplasty combined with tympanostomy tube insertion and middle ear pressure equalization therapy in treatment of recurrent secretory otitis media. Methods: Fifty one patients with recurrent secretory otitis media (62 ears) underwent balloon dilation of Eustachian tube and tympanic tube insertion under general anesthesia, followed by long term middle ear pressure equalization therapies. The Eustachian tube score (ETS) and Eustachian tube function questionnaire (ETDQ-7) were used for pre- and postoperative (up to 12 months) evaluation of Eustachian tube functions. Results: The mean ETS score was 2.34 ± 0.97 preoperatively, and 6.17 ± 1.54, 7.23 ± 1.62, 8.24 ± 1.97, and 7.63 ± 1.86 at 1, 3, 6 and 12 months postoperatively, respectively (P < 0.05). The ETDQ-7 score was 4.82 ± 1.07 preoperatively, and 2.20 ± 0.54, 2.32 ± 0.68, 2.53 ± 0.79, and 2.67 ± 0.76 at 1, 3, 6 and 12 months postoperatively, respectively (P < 0.05). Conclusion: Balloon dilation of Eustachian tube combined with tympanostomy and catheterization resulted in significant improvement of subjective symptoms and objective evaluation of Eustachian tube functions in most patients with recurrent secretory otitis media, as indicated by the ETS and ETDQ-7 scores, demonstrating high levels of efficacy and patient satisfaction.

INFLUENCE OF SO_4^(2-) AND Cl-ON THE CORROSION BEHAVIOR OF COPPER TUBE IN AIR-CONDITIONING SYSTEM

The influence of chloride or sulphur dioxide on the corrosion behavior of copper tube in the air-conditioning system was studied using scanning electron microscope (SEM), energy dispersion spectrometer (EDS) and cyclic polarization techniques. The results showed that the corrosion of copper tube are mainly caused by the SO42- and Cl- ions in the circulating water, and the former is mainly responsible for the general corrosion of the copper tube whilst the latter for the pitting corrosion. The different influences of SG42- and Cl- ions on the corrosion type of copper tube may be attributed to that the radius of SO42- ion is much larger than that of Cl- ion. Meanwhile the results also indicated that SO42- inhibits the pitting corrosion caused by Cl- and Cl- inhibits the general corrosion initiated by SO42- due to their competitive adsorption on the copper matrix.

Localized Corrosion in Copper Tubes by Volatile Organic Substance

An unusual form of localized corrsion in copper tubes was detected early in service and in leakage tests after manufacturing.The morphology of this corrosion is similar to that of an ant's nest when viewed in cross section. The corrosion mechanisms, cases ofant's nest corrosion, and preventive measures are presented.

Texture evolution and mechanical anisotropy of an ultrafine/nano-grained pure copper tube processed via hydrostatic tube cyclic expansion extrusion

Texture evolution and mechanical anisotropic behavior of an ultrafine-grained(UFG)pure copper tube processed by recently introduced method of hydrostatic tube cyclic expansion extrusion(HTCEE)was investigated.For the UFG tube,different deformation behavior and a significant anisotropy in tensile properties were recorded along the longitudinal and peripheral directions.The HTCEE process increased the yield strength and the ultimate strength in the axial direction by 3.6 and 1.67 times,respectively.Also,this process increased the yield strength and the ultimate strength in the peripheral direction by 1.15 and 1.12 times,respectively.The ratio of ultimate tensile strength in the peripheral direction to that in the axial direction,as a criterion for mechanical anisotropy,are 1.7 and 1.16 for the as-annealed coarse-grained and the HTCEE processed UFG tube,respectively.The results are indicative of a reducing effect of the HTCEE process on the mechanical anisotropy.Besides,after HTCEE process,a low loss of ductility was observed in both directions,which is another advantage of HTCEE process.Hardness measurements revealed a slight increment of hardness values in the peripheral direction,which is in agreement with the trend of tensile tests.Texture analysis was conducted in order to determine the oriental distribution of the grains.The obtained{111}pole figures demonstrate the texture evolution and reaffirm the anisotropy observed in mechanical properties.Scanning electron microscopy micrographs showed that different modes of fracture occurred after tensile testing in the two orthogonal directions.

Concrete-Filled Steel Tube Arch Bridges in China

In the past 20 years, great progress has been achieved in China in the construction of concrete-filled steel tube （CFST） arch bridges and concrete arch bridges with a CFST skeleton. The span of these bridges has been increasing rapidly, which is rare in the history of bridge development. The large-scale construction of expressways and high-speed railways demands the development of long-span arch bridges, and advances in design and construction techniques have made it possible to construct such bridges. In the present study, the current status, development, and major innovative technologies of CFST arch bridges and concrete arch bridges with a CFST skeleton in China are elaborated. This paper covers the key con- struction technologies of CFST arch bridges, such as the design, manufacture, and installation of steel tube arch trusses, the preparation and pouring of in-tube concrete, and the construction of the world＇s longest CFST arch bridge-the First Hejiang Yangtze River Bridge. The main construction technologies of rein- forced concrete arch bridges are also presented, which include cable-stayed fastening-hanging cantilever assembly, adjusting the load by means of stay cables, surrounding the concrete for arch rib pouring, and so forth. In addition, the construction of two CFST skeleton concrete arch bridges-the Guangxi Yongning Yong River Bridge and the Yunnan-Guangxi Railway Nanpan River Bridge--is discussed. CFST arch bridges in China have already gained a world-leading position; with the continuous innovation of key technologies, China will become the new leader in promoting the development of arch bridges.

Mathematical and Numerical Modelling of Copper Tube Extrusion after Optimizing Geometrical and Operating Parameters

This study aimed to optimize cross-sectional area of the extruder and the flow rate of the material through the extruder. Extrusion process was first modelized using the continuum mechanics method before being simulated with the commercial software LS-DYNA using the Johnson-Cook model based on the finite element method after optimization of the factors with simplex algorithm. The study was carried out on a connecting rod: diameter of 145 mm, cross-section of 1.65 m2, length of 0.25 m, volume of 0.41 m3 and a mass of 37 kg. Optimum parameters obtained were temperature of 850℃, flow rate of 0.237 m/s, die diameter of 19.2 mm, pin diameter of 14 mm, extrusion strength of 565.6 kN and press pressure of 245 GPa. From these factors, a blank was obtained with external and internal diameters of 19.2 and 14 mm respectively over a length of 28 m with a thickness of 2.6 mm. Simulation using LS-DYNA software resulted in a difference in values of 7.4% between optimization and simulation when the difference of 2.4% was found between modelling and simulation. These values make the process optimal for industrial application to improve the extrusion requirements of copper tubes.

Pressure Drop of Liquid–Solid Two-Phase Flow in the Vertical Tube Bundle of a Cold-Model Circulating Fluidized Bed Evaporator

A cold-model vertical multi-tube circulating fluidized bed evaporator was designed and built to conduct a visualization study on the pressure drop of a liquid–solid two-phase flow and the corresponding particle distribution.Water and polyformaldehyde particle(POM)were used as the liquid and solid phases,respectively.The effects of operating parameters such as the amount of added particles,circulating flow rate,and particle size were systematically investigated.The results showed that the addition of the particles increased the pressure drop in the vertical tube bundle.The maximum pressure drop ratios were 18.65%,21.15%,18.00%,and 21.15%within the experimental range of the amount of added particles for POM1,POM2,POM3,and POM4,respectively.The pressure drop ratio basically decreased with the increase in the circulating flow rate but fluctuated with the increase in the amount of added particles and particle size.The difference in pressure drop ratio decreased with the increase in the circulating flow rate.As the amount of added particles increased,the difference in pressure drop ratio fluctuated at low circulating flow rate but basically decreased at high circulating flow rate.The pressure drop in the vertical tube bundle accounted for about 70%of the overall pressure drop in the up-flow heating chamber and was the main component of the overall pressure within the experimental range.Three-dimensional phase diagrams were established to display the variation ranges of the pressure drop and pressure drop ratio in the vertical tube bundle corresponding to the operating parameters.The research results can provide some reference for the application of the fluidized bed heat transfer technology in the industry.