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In recent years, with the urgent need of the country to vigorously promote the transformation and upgrading of the construction industry and the modernization of the construction industry, it has been proposed to vigorously develop prefabricated buildings and increase the proportion of prefabricated buildings in new buildings. The prefabricated concrete building is a concrete structure with prefabricated components in the factory and processing and connection on the construction site. Because of its fast construction speed and good overall benefits, it is widely promoted. For prefabricated buildings, the key technology is the connection of structural nodes, and most of the component connections use concrete sleeve connections. The quality of the sleeve grouting material is very important. The basic formula of the grouting material leads to different and different mechanical properties. Conditions apply. This article starts with different sleeve grouting patents, summarizes different functions and characteristics, and provides a reference for the next development of sleeve grouting.

Background. Type 2 diabetes (T2D) as a worldwide chronic disease combined with the COVID-19 pandemic prompts the need for improving the management of hospitalized COVID-19 patients with preexisting T2D to reduce complications and the risk of death. This study aimed to identify clinical factors associated with COVID-19 outcomes specifically targeted at T2D patients and build an individualized risk prediction nomogram for risk stratification and early clinical intervention to reduce mortality. Methods. In this retrospective study, the clinical characteristics of 382 confirmed COVID-19 patients, consisting of 108 with and 274 without preexisting T2D, from January 8 to March 7, 2020, in Tianyou Hospital in Wuhan, China, were collected and analyzed. Univariate and multivariate Cox regression models were performed to identify specific clinical factors associated with mortality of COVID-19 patients with T2D. An individualized risk prediction nomogram was developed and evaluated by discrimination and calibration. Results. Nearly 15% (16/108) of hospitalized COVID-19 patients with T2D died. Twelve risk factors predictive of mortality were identified. Older age (HR = 1.076, 95% CI = 1.014–1.143,p=0.016), elevated glucose level (HR = 1.153, 95% CI = 1.038–1.28,p=0.0079), increased serum amyloid A (SAA) (HR = 1.007, 95% CI = 1.001–1.014,p=0.022), diabetes treatment with only oral diabetes medication (HR = 0.152, 95%CI = 0.032–0.73,p=0.0036), and oral medication plus insulin (HR = 0.095, 95%CI = 0.019–0.462,p=0.019) were independent prognostic factors. A nomogram based on these prognostic factors was built for early prediction of 7-day, 14-day, and 21-day survival of diabetes patients. High concordance index (C-index) was achieved, and the calibration curves showed the model had good prediction ability within three weeks of COVID-19 onset. Conclusions. By incorporating specific prognostic factors, this study provided a user-friendly graphical risk prediction tool for clinicians to quickly identify high-risk T2D patients hospitalized for COVID-19.

The effective dissolution of cellulose prepares for its subsequently full utilization. Ionic liquids (ILs) are attractive options for “green” dissolution of cellulose. A series of morpholinium-based ILs were synthesized and applied in dissolution of cellulose. The ultrasonic assisted saturated calcium chloride solution was used to activate cellulose. The remarkable decrease (from 87% to 65%) in crystallinity of cellulose facilitated dissolution process. The type of head-corn cations significantly increased polarity (ET(30)) and hydrogen bond acidity (α) of ILs. N-Allyl-N-methylmorpholinium-based ILs showed the highest ET(30) and α (59.11 kcal mol−1 and 0.51) compared to 1-Allyl-3-methylimidazolium-based ILs (57.41 kcal mol−1 and 0.46) and 1-Allyl-3-methylpyridinium-based ILs (49.36 kcal mol−1 and 0.33) owing to the electron-rich center of oxygen in the morpholine ring. The type of anions dominated the ability to accept hydrogen bond of ILs. Formate, acetate and bisulfate contributed more hydrogen bond basicity (β) (0.84, 0.88 and 0.91) for N-allyl-N-methylmorpholinium-based ILs in comparison with other anions. Additionally, morpholinium-based ILs exhibited appropriate viscosity. Above-mentioned performances jointly improved the dissolution of cellulose in morpholinium-based ILs. This study demonstrated the potential of using morpholinium-based ILs as a class of efficient solvents to dissolve cellulose.

Water pipeline scaling serious by prolonged use, result in a substantial diameter narrowed, reduced water efficiency. In order to solve this problem, analyzes the deposition feature and the dill descaling method, research on dill descaling theory and chip formation process. Choose multi-tooth bit as a foundation. According to the characteristics of processing object, improved the structure and cutting teeth distribution, get a new type of scaling drill. Take the inside wall of injection pipe and scale as research object, established finite element model for static analysis, get stress graph and stress curve, showed the wall stress state in drilling process.

The self-promotion platform jacking system has been dependent on imported equipment for a long time, independent research and development made the jacking system. According to the characteristics of operating conditions, the static bending strength of the tooth root of the climbing gear under the storm maintenance load was checked, and the calculation results of the three strength checking methods were given and compared. The gear material is made of high-quality alloy steel 40CrNiMo, which guarantees the good comprehensive mechanical properties after the heat treatment. By improving the CNC cutting machine, CNC flame cutting process produced crude tooth, adopting the precision CNC gear milling process made of refined tooth.

This paper presents a series of tests on the tensile, bending, welding, and threaded connection of 022Cr22Ni5Mo3N (2205) stainless steel bars. These tests prove whether the stainless steel bars have excellent mechanical properties and whether these steel bars meet technological requirements in preparing reinforcements for concrete construction. The use of stainless steel bars in concrete construction works in other highly corrosive environments, such as marine construction works, can reduce the maintenance and inspection costs and can extend the service life. Such application results in significant economic and social benefits.

Lignocellulosic biomass contains about 45% cellulose. The total reducing sugars (TRS) obtained from lignocellulosic materials is beneficial to the sustainable development. Natural deep eutectic solvents (NADESs) provide an attractive alternative for the “green” conversion of cellulose. In this work, series of amino acids based NADESs with FeCl3.6H2O as ligands catalyst were synthesized and characterized by in situ IR, FT-IR, 1H NMR and TG-DTA. NADESs showed great thermal stability. The efficient hydrolysis performance of cellulose in NADESs was investigated under mild conditions. The influencing factors such as the type of NADESs, reaction temperature, reaction time, and FeCl3.6H2O addition on the TRS yield were studied. The optimized process conditions for hydrolyzing cellulose in L-Proline/ Ethylene glycol/FeCl3.6H2O were molar ratio 1: 2: 1, reaction time 120 min and temperature 120 °C. The yield of total reducing sugar was 66.7%. The conversion mechanism was also investigated.

Acidic substances, which produced during chlorinated volatile organic compounds, will corrode the commonly used packing materials, and then affect the removal performance of biofiltration. In this study, three biofilters with different filter bed structure were established to treat gaseous chlorobenzene. CaCO3 and 3D matrix material was added in filter bed as pH buffering material and filter bed supporting material, respectively. A comprehensive investigation of removal performance, biomass accumulation, microbial community, filter bed height, voidage, pressure drops, and specific surface area of the three biofilters was compared. The biofilter with CaCO3 and 3D matrix material addition presented stable removal performance and microbial community, and greater biomass density (209.9 kg biomass/m3 filter bed) and growth rate (0.033 d−1) were obtained by using logistic equation. After 200 days operation, the height, voidage, pressure drop, specific surface area of the filter bed consisted of perlite was 27.4 cm, 0.39, 32.8 Pa/m, 974,89 m2/m3, while those of the filter bed with CaCO3 addition was 28.2 cm, 0.43, 21.3 Pa/m, and 1021.03 m2/m3, and those of the filter bed with CaCO3 and 3D matrix material addition was 28.7 cm, 0.55, 17.4 Pa/m, and 1041.60 m2/m3. All the results verified the biofilter with CaCO3 and 3D matrix material addition is capable of sustaining the long-term performance of biofilters. CaCO3 could limit the changes of removal efficiency, microbial community and filter bed structure by buffering the pH variation. And 3D matrix material could maintain the filter bed structure by supporting the filter bed, regardless of the buffering effect.

In recent decades, Electrical Resistance Tomography (ERT) has become a research focus. The application of ERT in practical engineering is still in the research stage, due to the resistivity is very high and not steady, limiting its development. The influencing factors of Graphite Electrically Conductive Concrete (GECC), such as the dosage of graphite, curing age, moisture content and so on, have been analyzed. A set of ERT system of GECC has been proposed and designed based on PXI platform. This paper mainly shows experiments on ERT of GECC structure. The targets given with defects have been used for imaging. By examining, the law of the GECC imaging in different conductivity matrix has been got. Meanwhile, this paper determines the resistivity threshold in the ERT system, and validates the detection accuracy of the model with defects.

To investigate the laws of creep and shrinkage in high-strength, concrete for long-span prestressed continuous box-girder bridge and predict long-term deflection, strain sensors were embedded in the midspan of a box-girder bridge. The shrinkage strain of concrete was then directly measured, and the creep strain was obtained using the incremental algorithm of measured data. The measured data show that if the creep and shrinkage model in the existing specification is used, then the shrinkage effect is underestimated as a whole and the creep effect is overrated for the C55 high-strength concrete of the bridge. The long-term deflection is predicted using the modified prediction models of creep and shrinkage that are based on short-term measured data when the bridge is under dead load. The deflection prediction values of two modified prediction models were compared with the measured deflection. Results of the comparison indicate that the integrality of the short-term measured strain data in concrete, measurement accuracy, and modified prediction model that is based on the measured data influence the prediction accuracy of the modified prediction models.

Concrete filled steel tubular structure is a new type of composite structure, widely used in monolayer or multilayer industrial workshop structure column, frame column, all kinds of equipment support and super high-rise building and bridge structure, connection pipe attracted more research on its theory and experiment at home and abroad on the concrete force has carried on the preliminary summary, analysis of the advantages and disadvantages of concrete filled steel tube of various existing connection mode, and illustrates the current situation of domestic and international research on concrete filled steel tube are connected, and finally puts forward some problems in the study.

Based on the piezoelectric impedance technology, damages in concrete specimens could be monitored. The structural damages were simulated by pasting piezoelectric ceramic chips and boring several holes on the surface of concrete specimens. And then, with the precision impedance analyzer HP4192A, we measured the conductance spectrum curve of the specimens.The specimens were in two different damage situations：one was damaged in one place to varying degrees and the other was damaged in different locations to the same degree. The experiment results show that the damages in the specimens can lead to the drift of the conductance spectrum curve and the greater the damages are, the greater the change will be.

Medical endoscopes have gained widespread applications in minimally invasive surgery. There are increasing needs to accurately evaluate their performance characteristics which are beneficial to the product design, manufacture, repair and supervision. This paper gives a review of the measurement methods for the imaging and photometric characteristics of the endoscopes, such as resolution, modulation transfer function, light loss, illumination uniformity, which are very important for the evaluation of the image quality. In actual measurement, the verification of a test device itself and the uncertainty assessment or error analysis of the measurement results are also very necessary from the view point of metrology.

Water pipeline scaling serious by prolonged use, result in a substantial diameter narrowed, reduced water efficiency. Mechanical cleaning is a kind of economic and security cleaning method, current drilling scaling equipment cannot clean effectively. In order to solve this problem, analyzes the dill descaling method. Choose multi-tooth bit as a foundation. Established finite element model for static analysis, gets three direction force diagram. Optimal design drill structure, created a new type of scaling drill. Compared two kinds force analysis results, by improving the structure, distributed stress on multiple cutting tooth, improved cutting conditions, enhanced the drill descale and feed ability, and improved the working life of the unit. Carried out static and dynamic finite element analysis, provide a theoretical basis for follow-up design.

A range profile synthetic algorithm of the stepped-frequency chirp train waveform is designed to obtain HRRP (High Resolution Range Profile) in this paper. Based on waveform model, grating lobes restraining method is proposed with the help of autocorrelation function. Due to the matched filter operation, image energy spill over the close range bins, which causes “ghost images”. Set parameters of inner pulse bandwidth, stepped frequency and chirp compression envelop sampling frequency properly, and then carry the synthetic algorithm, the “ghost images” are restrained. All of the results are validated by simulation.

A straight pipe viscometer is proposed, which consists of the measuring sub-system and the data-acquisition and signal processing sub-system. The measuring sub-system include straight pipe, pressure transmitter, Coriolis flow-meter and slurry bump, and the data-acquisition and signal processing sub-system include single-chip processor, A/D converter, digital display, serial output port, drive circuit and so on. The measuring principle and working process of the straight pipe viscometer are analyzed. The measurement data and results are given and compared with test results of rotary viscometer in the same test conditions. The measuring accuracy is 3% at 5-150mPas, and the online measurement of viscosity is implemented.

Deep eutectic solvents (DESs) offer attractive options for the “green” dissolution of cellulose. However, the protic hydroxyl group causes weak dissolving ability of DESs, requiring the substitution of hydroxyl groups in the cation. In this study, a novel allyl-functionalized DES was synthesized and characterized, and its possible effect on improved dissolution of cellulose was investigated. The DES was synthesized by a eutectic mixture of allyl triethyl ammonium chloride ([ATEAm]Cl) and oxalic acid (Oxa) at a molar ratio of 1:1 and a freezing point of 49 °C. The [ATEAm]Cl-Oxa exhibited high polarity (56.40 kcal/mol), dipolarity/polarizability effects (1.10), hydrogen-bond donating acidity (0.41), hydrogen-bond basicity (0.89), and low viscosity (76 cP at 120 °C) owing to the π-π conjugative effect induced by the allyl group. The correlation between temperature and viscosity on the [ATEAm]Cl-Oxa fit the Arrhenius equation well. The [ATEAm]Cl-Oxa showed low pseudo activation energy for viscous flow (44.56 kJ/mol). The improved properties of the [ATEAm]Cl-Oxa noticeably promoted the solubility (6.48 wt.%) of cellulose.

Emergency logistics system contains information on material reserves, emergency command and emergency distribution. In this paper, the aspect of emergency distribution only is analyzed in microscopic, mathematical model of emergency logistics distribution has been established in considering the traffic situation and shortage degree. On the aspect of model solution, improved ant colony algorithm, which can enhance the selectivity of finding the best solution in emergency logistics distribution routing, is used in solving the model.

In this essay, the solution about emergency logistics distribution routing optimization has been analyzed by quantitative methods, and the mathematic model focusing on trying the best to shorten distribution time has been established, in which the actual situations of the pathways and the shortage of goods at each affected point have been considered in order to keep further close to the real circumstances where had suffered disaster. Using the Chaos Ant Colony Algorithm solves the mathematic model. The experimental simulation indicates that the arithmetic is feasible and effective to settle the problem about the optimization of emergency logistics distribution route.

As a common type of bridge, the reinforced concrete simply supported T-girder bridges have some usual disease problems such as web vertical cracks, incline cracks near the supports and diaphragm damage, and so on injured by transportation loads. In Shanxi province most of T-girder bridges appear to be under strength for current vehicle loads because most of which are designed by conventional methods and the old codes so it is important to evaluate how the existing damage influence the ultimate bearing capacity of the bridge. The destructive test is a directive mean of verifying the ultimate bearing capacity of bridges. This paper provides details of a destructive load test of a T-girder bridge called Zuojiabao Bridge. It describes the analysis performed prior to testing, aimed at predicting the response of the structure at both serviceability and ultimate states, and discusses the results obtained.The development rule of strain, deflection and crack and the ultimate bearing capacity of the bridge were obtained through the destructive test process. The results showthat although the old T-girder bridge has enough bearing capacity to satisfy the new vehicle standard, it is strongly recommended to strengthen or retrofit the bridge. And the finite element analysis can be effectively applied to the failure analysis of the reinforced concrete T-girder bridge subjected to destructive load.

Immature dendritic cell-derived exosomes (iMDEX) display a certain degree of immunosuppressive activity in autoimmune diseases. However, the role of iMDEX in experimental autoimmune myasthenia gravis (EAMG) is still unclear. Therefore, we tested the effects of mouse bone marrow (BM)-derived iMDEX on tolerance induction in a mouse model of EAMG. In this study, we found that the CELLine culture system produced more exosomes, the morphology and phenotype of these exosomes were found to be identical when compared with traditional cell culture. And, iMDEX(1000) ameliorated the progression of EAMG by reducing AChR-reactive lymphocyte proliferation, AChR antibody levels and pro-inflammatory cytokine levels.

Two metallothionein cDNAs (MT-A and MT-B) in the fresh-water fish crucian carp (Carassius cuvieri TEMMINCK et SCHLEGEL) were cloned. Sequence analysis of both cDNAs gave the structure of a coding region corresponding to 60 amino acid residues. The homology of their deduced amino acid sequences was completely conserved at the positions of the cysteine residue, but a significant difference existed in the size of their 3'-untrans-lated regions (130 base pairs for MT-A and 280 base pairs for MT-B). Direct amino acid sequencing of the MT-II isoform purified by HPLC was accomplished for up to 30 residues and its sequence was identical to that deduced from MT-B cDNA. This is the first case in vertebrates that N-terminal methionine in crucian carp MT-II was not blocked. By northern blot analysis, basal and cadmium chloride- or dexamethasone-induced MT-B (MT-II) mRNAs were detected time dependently after treatment. On the other hand, the expression of MT-A mRNA was extremely low. These results indicate that the MT isoform II in crucian carp is coded by the MT-B gene, and that the MT-B-dominant expression of mRNA in crucian carp may be due to the difference in the 3'-untranslated regions of MT mRNAs.

The induction of metallothionein (MT) by physical and chemical stress was assessed using the fresh-water fish, crucian carp (Carassius cuvieri Temminck et Schlegel). The fish exposed to violent air-pumping stress for 6 days revealed time-dependent induction of MT-like metal-binding proteins in both their livers and kidneys. Their hepatic contents after exposure to stress were elevated to twice the basal level with 24 h, resulting in more than a 3-fold increase at 144 h, whereas their renal contents gradually increased after 24 h and reached the same level as that in the liver around 96 h. Two major inducible proteins were purified from livers of fish exposed to stress and were shown to be MT based upon their chromatographic behavior, UV absorption spectra and their molecular weights. Consequently, they were termed ccMT-1 and ccMT-2, according to their elution sequence upon anion-exchange chromatography. Both proteins mainly bound zinc in their endogenous forms and showed different immunogenicity to rat and rabbit MTs. Dexamethasone, a potent inducer for MT synthesis in mammals, induced the production of both isoforms in crucian carp, whereas cadmium and zinc ions prominently induced the synthesis of ccMT-2. These results indicate that crucian carp have the ability to produce MTs in response to various kinds of environmental stress and that violent air-pumping stress in crucian carp may induce MT synthesis, in part, via the release of endogenous factor(s), such as glucocorticoids.

To evaluate the CT imaging characteristics of incomplete and complete myocardial bridges-mural coronary artery (MB-MCA).Fifty subjects with dual source coronary CT angiography (DSCTA) evidenced MB were included. The subjects were divided into incomplete MB-MCA and complete MB-MCA groups. The diameter of MCA in best systole phase and diastole phase, the MCA stenosis rate, the presence of atheromatous change proximal to the MB were evaluated.There were 58 MB, the average length was (2.02 ± 1.02) cm, 23 were incomplete MB and 35 were complete MB. Thirty-two MB were in the middle segments of left anterior descending artery (55.2%); 17 MB were in the distal segment of the left anterior descending artery (29.3%); 1 MB was in the proximal segment of left anterior descending artery; 3 MB in diagonal branch; 4 MB in obtuse marginal branch, 1 MB in distal right coronary artery. It was statistically significant difference between the incomplete MB-MCA and the complete MB-MCA of the diameter change in diastole and systole phase [(1.93 ± 0.49) mm, (1.71 ± 0.45) mm vs. (2.21 ± 0.41) mm, (1.63 ± 0.52) mm, P = 0.008] and stenosis rate (10.38% ± 20.2% vs. 25.12% ± 21.02%, P = 0.01). Atherosclerotic finding was evidenced in 8 incomplete MB (34.78%) and 15 complete MB (42.86%) at the proximal vessel of mural coronary artery (P0.05).DSCTA can vividly display the incomplete and complete myocardial MB, accurately evaluate the shape change of MB-MCA in diastole and systole phase and detect the atherosclerotic change in the proximal vessel of MB.

By considering the random excitation of irregular pavement, the vehicles and the concrete box girder bridge with corrugated steel webs can be taken as an interaction system. Based on the finite element method, the bridge finite element analysis (FEA) model is built. According to the vehicle-bridge coupling vibration theory, the control matrix of modal parameters of the concrete box girder bridge with corrugated steel webs can couple with the dynamic parameters matrix of the vehicles. And the irregular pavement function is applied in the bridge model as an excitation. By considering the effect of the irregular pavement on vehicle-bridge coupling vibration response, a program is compiled. By analyzing the relationship between vehicle speed, irregular amplitude, irregular wavelength and dynamic load coefficient, it can be obtained that vehicle speed and surface roughness both are the most important factors. So the beneficial references to dynamic design, vibration control, and the dynamic performance evaluation for the concrete box girder bridge with corrugated steel webs, can be provided.

Metallothionein-3 (MT-3), renamed as growth inhibitory factor (GIF), is a brain specific member of the metallothionein family. Human dUTPase is a recently found protein in brain that can interact with hMT-3. They have the growth inhibitory activity on neuron cell by interaction. To study the affection of hMT-3 to dUTPase's eliminating the cellular toxicity caused by dUTP, the pSVHA-dUTPase and pFLag-hMT-3 genes have been transfected into HEK293 cells. In addition, the dUTPase and hMT-3 proteins were expressed in BL21 to study the role of hMT-3 on the hydrolyzation of dUTP by dUTPase. The results demonstrate that the cells co-transfected with dUTPase and hMT-3 genes have more strong resistibility to dUTP than the cells transfected only with dUTPase gene. And that the hMT-3 protein can accelerate the hydrolyzation of dUTP by dUTPase. All these indicate that hMT-3 can cooperate with dUTPase to protect better the 293 cells from dUTP. This research offered the theoretic elements for the application of hMT-3 and dUTPase in chemic cure.

In order to examine the elusive functional mechanism of GIF (Neuronal growth inhibitory factor, GIF) and elucidate the possible relationship between GIF and Alzheimer's disease, we constructed bait1 plasmid (pHyblex-GIF) by cloning GIF cDNA directly in frame with plasmid pHyblex, and used the yeast two-hybrid system to screen Alzheimer's disease human brain cDNA library and found the GIF-interacting proteins. The final results from coimmunoprecipitation and western blotting experiments confirmed that interacting proteins specifically binds to GIF. After sequencing the nucleotide of the putative positive plasmids and searching for homologues, we found that one of these is the part of human nuclear dUTPase protein sequence. Then the dUTPase genes are cloned into pGEX-4T-1, the fusion expression vector of GST,and highly expressed in E. coli BL21. The proteins dUTPase and GIF were purified and obtained by affinity chromatography, thrombin digestion and gel filtration on Sephacryl S100. It demonstrated that the proteins dUTPase and GIF had the growth inhibitory activity on co-cultured neuron in vitro. The inhibitory curve was very similar to the GIF. It's possible that dUTPase is one of the proteins interacting with GIF in Alzheimer's disease human brain extracts.

Neuronal growth inhibitory factor (GIF), known also as metallothionein-III (MT-III), was the first validated to be capable of inhibiting growth of neuronal cells in nervous system, its beta-domain being functional. GIF functional di-domain (GIFbeta- beta) was constructed to study the structure and function of GIF. N terminal beta-domain and C terminal beta-domain cDNAs were amplified by PCR, inserted into vector pGEX-4T-1 and expressed in Escherichia coli, as carboxyl terminal extension of glutathione-S-transferase (GST), by IPTG induction. After digestion by thrombin, the fusion protein was isolated by passing through a glutathione-Sepharose 4B affinity chromatography column and was purified by gel fit ration on Sephacryl-S100. About 60 mg protein per liter of bacterial cell culture was achieved. The results of SDS-PAGE, amino acid composition, molecular mass, the ratio of metal/protein and sulfhydryl group/protein showed that the purified protein was the GIFbeta- beta. Circular dichroism (CD) spectroscopy show GIFbeta- beta has characteristic metal-sulfhydryl clusters of metallothionein family. Inhibitory activities detected by the MTT reduction assay are: GIFGIFbeta-betaGIF beta-domain.

Metallothionein (MT), a metal-binding protein induced primarily by heavy metals in vertebrates, is considered a biomarker for environmental heavy-metal contamination. To investigate heavy metal pollution in the freshwater environment, MT-I and MT-II were purified from livers of crucian carp (Carassius carassius) by gel exclusion chromatography and ion exchange chromatography. To detect the purified MT-II, a specific monoclonal antibody (mAb) against crucian carp MT-II was produced from the hybridoma strains by cell-cell fusion. By using Enzyme-Linked Immunosorbent Assay (ELISA) with this mAb, the purified crucian carp MT-II was detected with a high specificity and sensitivity. There was a good correlation between the amount of MT-II in carp livers and the concentration of heavy metals in water. ELISA was then used to evaluated the degree of heavy metal pollution in two freshwater systems. The results indicate that the MT-II content in carp liver tissue can be used as an indicator of environmental heavy-metal pollution.