[ Objective] To extract non-specific transfer factors (TFs) from goose spleens and to detect the activity of the extracts. [Methodl The non-specific TFs were extracted crudely from goose spleens using the dialysis m...[ Objective] To extract non-specific transfer factors (TFs) from goose spleens and to detect the activity of the extracts. [Methodl The non-specific TFs were extracted crudely from goose spleens using the dialysis method, and the effects of the extracts on immunity were studied. [ Result] The extracts of goose TFs were transparent, light yellow and non-toxic. The extracts were at pH 6.72 and did not contain higher molecular weight proteins. The concentration of minor polypeptides was 23.78 ug/ml. The results of immunization test showed that the level of antibodies was higher in the geese inoculated with the inactivated vaccine against infections serositis and the extracts of TFs than in the control geese injected with normal saline. In addition, the level of antibodies was significantly higher in the geese only inoculated with inactivated vaccine than in the control geese. The results showed that the extracts of TFs from goose spleens could enhance immunity to a certain extent. [ Conclusion] The study pro- vides a theoretical basis and technical reference for further researches on the biological activity of non-specific TFs from goose spleens as well as for application of the extracts.展开更多
In order to examine the factors which affect the range of heat transfer in earth surrounding subways, FLAC3D was adopted in this study to analyze these factors, under different conditions, in a systematic manner. When...In order to examine the factors which affect the range of heat transfer in earth surrounding subways, FLAC3D was adopted in this study to analyze these factors, under different conditions, in a systematic manner. When we compare these numerical tests, the results show that the main factors, affecting the heat transfer range are the thermal properties of the surrounding earth, the initial ground temperature and the temperature in the tunnel. The heat transfer coefficient between air and linings has little effect on the temperature distribution around the tunnel. The current results can provide a reference for improving the thermal environment in subways and optimizing the design of subwav ventilation and air conditioning.展开更多
Study was carried out to analyze the distribution and migration patterns,soil-to-plant transfer and potential health risks of chromium in soil-vegetable system in areas near a ferro-alloy manufactory in Hunan province...Study was carried out to analyze the distribution and migration patterns,soil-to-plant transfer and potential health risks of chromium in soil-vegetable system in areas near a ferro-alloy manufactory in Hunan province.The results show that soils near sewer outlet,sewer channel and in control area are averaged 2 239.5,995.33 and 104.9 mg/kg,respectively.The total Cr has a relative accumulation in soil depth of 200-400 mm near the sewer outlet,mainly enriches in the surface layer(0-200 mm) near the sewer channel and decreases gradually in unpolluted soils.The differential concentration level of enrichment between layers is little.The results also indicate that the three vegetables of celery,lettuce and Chinese cabbage are able to convert the potentially toxic Cr(Ⅵ) species into the non-toxic Cr(Ⅲ) species,and the chromium contents in the edible parts of the vegetables are averaged 11.95 mg/kg.The transfer factors of the three vegetables follow the order:Chinese cabbage lettuce celery.The estimated total daily intake of chromium substantially exceeds the dietary allowable value,which may pose health risks to local population.展开更多
Experiments and simulations on flow and heat transfer behavior of Therminol-55 liquid phase heat transfer fluid have been conducted in a ribbed tube with the outer diameter and inner diameter 25.0 and 20.0 mm,pitch an...Experiments and simulations on flow and heat transfer behavior of Therminol-55 liquid phase heat transfer fluid have been conducted in a ribbed tube with the outer diameter and inner diameter 25.0 and 20.0 mm,pitch and rib height of 4.5 and 1.0 mm.respectively.Experimental results show that the heat transfer and thermal performance of Therminol-55 liquid phase heat transfer fluid in the ribbed tube are considerably improved compared to those of the smooth tube.The Nusselt number increase with the increase of Reynolds number.The increase in heat transfer rate of the ribbed tube has a mean value of 2.24 times.Also,the pressure drop results reveal that the average friction factor of the ribbed tube is in a range of 2.4 and 2.8 times over the smooth tube.Numerical simulations of three-dimensional flow behavior of Therminol-55 liquid phase heat transfer fluid are carried out using three different turbulence models in the ribbed tube.The numerical results show that the heat transfer of ribbed tube is improved because vortices are generated behind ribs,which produce some disruptions to fluid flow and enhance heat transfer compared with smooth tube.The numerical results prove that the ribbed tube can improve heat transfer and fluid flow performances of Therminol liquid phase heat transfer fluid.展开更多
In this paper, it is offered to use the method of modulated reflection for the measurementof complex transfer factor of a radome wall on various sites of its surface. The circuit of equipmentallowed to carry out of su...In this paper, it is offered to use the method of modulated reflection for the measurementof complex transfer factor of a radome wall on various sites of its surface. The circuit of equipmentallowed to carry out of such measurement is given. The advantage of the given method in comparisonwith measurements on a gleam is shown. The results of the experimental research are given and theestimation of the accuracy of proposed method is considered.展开更多
Experiments about heat transfer in the presence of a two-phase flow due to the condensation of a R1234yf refrigerant have been performed considering a smooth tube and two micro-fin tubes.The following experimental con...Experiments about heat transfer in the presence of a two-phase flow due to the condensation of a R1234yf refrigerant have been performed considering a smooth tube and two micro-fin tubes.The following experimental conditions have been considered:Condensation temperatures of 40℃,43℃ and 45℃,mass fluxes of 500–900 kg/(m^(2)·s),vapor qualities at the inlet and outlet of the heat transfer tube in the ranges 0.8–0.9 and 0.2–0.3,respectively.These tests have shown that:(1)The heat transfer coefficient increases with decreasing the condensation temperature and on increasing the mass flux;(2)The heat transfer coefficient inside the micro-fin tube is larger than that for the smooth tube;(3)The heat transfer enhancement factors for the micro-fin tube with a fin helical angle of 8°and 15°are 2.51–2.89 and 3.11–3.57,respectively;both are higher than the area increase ratio.These experimental results have been compared with correlations available in the literature:the Cavallini et al.correlation has the highest accuracy in predicting the heat transfer coefficient inside the smooth tube,the related percentage error and the average prediction error are±8%and 0.56%,respectively;for the micro-fin tube these become±25%and 6%,respectively.展开更多
The activity concentrations of radionuclides, absorbed dose rate, excess lifetime cancer risk, and soil-to-plant transfer factor have been evaluated in soil and crop samples from Jalingo and Wukari Local Government Ar...The activity concentrations of radionuclides, absorbed dose rate, excess lifetime cancer risk, and soil-to-plant transfer factor have been evaluated in soil and crop samples from Jalingo and Wukari Local Government Area of Taraba State, Nigeria. The activity concentrations were determined with the aid of High Purity Germanium detector. The absorbed dose and excess lifetime cancer risk were evaluated and forecasted for 60 years using the ResRad off-site model. The average activity concentration of <sup>40</sup>K, <sup>232</sup>Th, and <sup>238</sup>U in the soil samples were 633.13, 141.15, and 71.20 Bq·kg<sup>-1</sup> respectively, for the Jalingo study area, and while that of the Wukari study area was;199.21, 87.23, and 25.37 Bq·kg<sup>-1</sup> respectively. The average soil-to-plant transfer factors for <sup>40</sup>K, <sup>232</sup>Th, and <sup>238</sup>U were 0.51, 0.10, and 0.27 respectively for the Jalingo study area while that of Wukari are 0.40, 0.57, and 0.74 respectively. The mean annual effective dose equivalent for the study area is higher than the world average of 0.07 mS·vy<sup>-1</sup>. The excess lifetime cancer risk for the study areas has values that are higher than the safety limit. The ResRed model showed that direct radiation from the crops is the major contributor to excess cancer risk among other pathways. The radiological hazard indices reveal health risks to farmers, especially in the Jalingo area.展开更多
In liquid-liquid systems, the substrates in the liquids are inaccessible to each other for the reaction. By adding a small quantity of phase transfer catalyst, the reaction can be made accessible and accelerated. The ...In liquid-liquid systems, the substrates in the liquids are inaccessible to each other for the reaction. By adding a small quantity of phase transfer catalyst, the reaction can be made accessible and accelerated. The present study involves the phase transfer catalyzed oxidation of 2-methyl-l-butanol by quaternary ammonium permanganate (tricaprylyl methyl ammonium permanganate). The attempt was to compare the kinetics under homogeneous and heterogeneous conditions. Experiments were conducted in a batch reactor to determine the kinetics under homogeneous conditions. A baffled horosilicate agitated reactor was used to find the enhancement factor and the kinetics under heterogeneous conditions. The rate constants determined under both homogeneous and heterogeneous conditions agreed very weU. The oxidation was found to be first order with respect to each of the reactants, quaternary ammonium permanganate and the alcohol, resulting in an overall second order rate expression. Aliquat336 (tricaprylylmethylammonium chloride) was found to be the best compared with the other catalysts tested (triethylbenzylammonium chloride, tetrabutylammonium bromide, tetrabutylammonium iodide and tetrabutylammonium hydrogen sulfate) and it gave an enhancement factor of 9.8.展开更多
Accumulation of heavy metals in agricultural soils is instigated by industrial and other human activities such as mining,smelting,cement-pollution,energy and fuel production,power transmission,traffic activities,inten...Accumulation of heavy metals in agricultural soils is instigated by industrial and other human activities such as mining,smelting,cement-pollution,energy and fuel production,power transmission,traffic activities,intensive agriculture,sludge dumping and melting operations.Plants received heavy metals from soils through ionic exchange,redox reactions,precipitation-dissolution,and so on,which implies that the solubility of trace elements based on factors like minerals in the soil(carbonates,oxide,hydroxide etc.),soil organic matter(humic acids,fulvic acids,polysaccharides and organic acids),soil pH,redox potential,content,nutrient balance,other trace elements concentration in soil,physical and mechanical characteristics of soil,soil temperature and humidity,and so on.In this study,the soil-edible plant and soil-water Transfer Factor(TF)for various metals showed that the TF values differed slightly between the locations.On soil-edible plant transfer,the mean TF for different heavy metals in soil-edible plants decreased in the following order:As(0.6)mg/kg>Cd(0.1)mg/kg>Cr(0.06)mg/kg>Pb(0.003)mg/kg>Ni(0.001)mg/kg.The total TF for different locations decreases in the following order:Barkin Ladi(1.0)mg/kg>Jos South and Jos East(0.7)mg/kg>Bassa and Mangu(0.6)mg/kg.On soil-water transfer,the mean TF for different heavy metals in soil-edible plants decreased in the following order:Cd(0.001)mg/L>As(0.0007)mg/L>Cr(0.0005)mg/L>Pb(0.0001)mg/L and Ni(0.0001)mg/L.The total TF for different locations decreases in the following order:Jos South(0.003)mg/kg>Barkin Ladi,Bassa,Jos East and Mangu(0.002)mg/kg.Based on the findings of this study,it can be concluded that the water and edible plants in the study area are good for public consumption,even though,regular checking of heavy metals in the study area is recommended.展开更多
Phytoremediation is a relatively new approach in remediating ecosystems contaminated by ecotoxic pollutants such as herbicides or heavy metals and especially cadmium (Cd). Certain indicators of phytoremediation, as ...Phytoremediation is a relatively new approach in remediating ecosystems contaminated by ecotoxic pollutants such as herbicides or heavy metals and especially cadmium (Cd). Certain indicators of phytoremediation, as plant growth, tolerance to Cd, and uptake, transfer factor (TF) and percent removal of Cd, were studied for 11 crops and 8 weed species in soil with varying levels of Cd (0-240 mg Cd kg" soil) under controlled environment. Cadmium accumulated mainly in roots (51%-86%, depending on the species), while a 14%-49% was transferred to shoots (except for four species) the concentration being positively related to Cd level in soil. Highest concentration in the above ground plant part was measured in sugarbeets (41-101 mg Cd kg-1 DW) followed by Bromus sterilis (75), Eruca sativa (32-82), Cichorium intibus (35-80), and maize (60 mg Cd kgl). Based on the results it is concluded that sugarbeets, maize, C. intibus, B. sterilis, E. sativa, Apium graveolens, and Vicia sativa seem to have a potential in remediating Cd contaminated soils.展开更多
This study aims to assess the effective capacity of <i>Panicum</i><span> <i>maximum</i> </span>to accumulate cadmium (Cd), nickel (Ni) and lead (Pb). <i>P</i><span>...This study aims to assess the effective capacity of <i>Panicum</i><span> <i>maximum</i> </span>to accumulate cadmium (Cd), nickel (Ni) and lead (Pb). <i>P</i><span>. <i>maximum</i></span> observed in a greenhouse was subjected to 2 ppm of Cd, 50 ppm of Ni, 100 ppm of Pb contaminated soil and uncontaminated soil, </span></span><span><span><span style="font-family:"">for</span></span></span><span><span><span style="font-family:""> 120 days. Plant growth and biomass produced concentration of trace metals in soil and plant, bioaccumulation and transfer factors, location of potentially toxic elements in tissues and cells of plant ha</span></span></span><span><span><span style="font-family:"">ve</span></span></span><span><span><span style="font-family:""> been determined. Stem length and biomass produced by <i>P</i><span>. <i>maximum</i></span> were higher on the uncontaminated soil followed respectively by those of soil-contaminated by Pb, Cd and Ni. Bioaccumulation factors of trace metals were 8.93 (Pb), 8.47 (Ni) and 3.37 (Cd). Ni was more accumulated in shoot biomass (FT > 1), while Pb and Cd were concentrated in root biomass (FT </span></span></span><span><span><span style="font-family:""><</span></span></span><span><span><span style="font-family:""> 1). Pb is accumulated preferentially in endodermis (roots) and epidermis (leaves). As for Ni and Cd, they are concentrated in central cylinder of roots and in conductive bundles of leaves. At cellular level, Ni and Cd are mainly concentrated in intracellular compartments of leaves and roots, while Pb is strongly detected at cell walls.展开更多
The role that a learner's native language plays in his or her second language acquisition (SLA) has been the focus of many researchers in the past few decades. The article provides a brief review of the literature ...The role that a learner's native language plays in his or her second language acquisition (SLA) has been the focus of many researchers in the past few decades. The article provides a brief review of the literature on the importance and the factors of native language influence in SLA.展开更多
Accumulation of metals in both sediments and Phragmites australis organs was studied. Samples were collected from seven stations located in Anzali wetland, Iran. The samples were analyzed by inductively coupled plasma...Accumulation of metals in both sediments and Phragmites australis organs was studied. Samples were collected from seven stations located in Anzali wetland, Iran. The samples were analyzed by inductively coupled plasma mass spectrometry(ICP-MS). The results showed that concentration of the studied metals(except As and Cd) were higher in sediments than in P.australis organs. Metal accumulation was found to be signifi cantly(P <0.05) higher in roots than in above-ground organs of P.australis. The bioaccumulation factor(BAF) and the transfer factor(TF) also verifi ed the highest rate of metal accumulation in roots and their reduced mobility from roots to the above-ground organs. Pearson correlation coeffi cient showed signifi cant relationships between metal concentrations in sediments and those in plant organs. It should be pointed out that sediment and plant samples exhibited higher metal concentrations in eastern and central parts than in western and southern parts of the wetland. The mean concentrations of all studied elements(except for Fe, V and Al) were higher in these sediment samples than in the Earth's crust and shale. High accumulation of metals in P. australis organs(roots and shoots) is indicative of their high bioavailability in sediments of the wetland. The correlation between metal concentrations in sediments and in P. australis indicates that plant organs are good bioindicators of metal pollution in sediments of Anzali wetland.展开更多
In this study, sixteen soil and vegetable samples from Tafila district were collected and analyzed from eight locations. Measurements of specific activity of natural gamma emitter radionuclides, 23SU and 235U, in thes...In this study, sixteen soil and vegetable samples from Tafila district were collected and analyzed from eight locations. Measurements of specific activity of natural gamma emitter radionuclides, 23SU and 235U, in these samples using gamma spectrometry, with the help of Genie 2000 software. Measurements were used to calculate the soil-vegetable transfer factor, and then the external radiation dose and internal radiation dose due to radioactivity of the ingested food. The specific activity of238U and 235U in soil were found to vary from (in Bq/kg): 26-575 and 1.4-35.5, respectively. The specific activity of 238U and 235U in vegetables were found to vary from (in Bq/kg): 0.019 to 0.632 and 0.0013-0.0375, respectively. The calculated transfer factor of Z3SU and Z35U range from 5.9 × 10^-4to 14.6 × 10^-4 for 238U and 4.9 × 10^-4 to 16.1 × 10^-4 for 235U. External absorbed dose rates were calculated to be in the range from 12.42 to 266.00 nGy/h. The annual effective dose was found to vary from 28.94 to 619.78 μSv/y. The annual internal effective dose due to 23SU and 23SU for fresh weights ofvegetablesl were found to vary from 0.9 × 10^-3 to 35.1 × 10^-3 μSv/y for 238U and 0.61 × 10^-4 to 17.62 × 10^-4 μSv/y for 235U.展开更多
Clinical observation on 48 cases of stomach carcinoma pain indicated that acupuncture including filiform needle group and point-injection group had better therapeutic effects in treatment of stomach carcinoma pain whe...Clinical observation on 48 cases of stomach carcinoma pain indicated that acupuncture including filiform needle group and point-injection group had better therapeutic effects in treatment of stomach carcinoma pain when patient's mind was concentrated at the site of disease. After treatment for 2 months, the long-term effective rates of analgesia in both the filiform needle group and the point-injection group were similar to that in the western medicine group, all being about 81%. While the long-term markedly effective rates in the two groups were superior to that in the western medicine group. Life quality of the patients in all the groups were improved. The toxic action and side effects caused by chemotherapy were prevented, the high viscous state showed by indexes of blood rheology was improved, and the lowered Cu-Zu-SOD activity in erythrocytes in patients of stomach carcinoma was increased in the filiform needle group and the point-injection group. Based on the results of clinical study, we consider that acupuncture analgesic effect on stomach carcinoma is related to the increase of PLEK, improvement of cellular immune function and the elevation of life quality after acupuncture.展开更多
In this study,the usage wastewater from secondary treatment in feeding fishes of Carassius gibelio species and suitability of the fishes for human food were evaluated.The metals(Ag,Al,As and B)in treated effluent and ...In this study,the usage wastewater from secondary treatment in feeding fishes of Carassius gibelio species and suitability of the fishes for human food were evaluated.The metals(Ag,Al,As and B)in treated effluent and skeleton,skin,eyes and brain tissues of fishes were examined seasonally.It was found that treated effluent was not suitable for irrigation and aquaculture in terms of Al according to the Turkish standard values.According to annual averages the size order of Ag and B concentrations were skeleton>skin>eyes>brain and skeleton>skin>brain>eye respectively.Also,skin>brain>eyes>skeleton was for As and Al.TF(Transfer Factor)values of all metals examined were determined as>1 in the four tissues and the metals caused bioaccumulation because of treated effluent.Concentrations in muscles were found 7 to 6227 times higher than in water.The size order of TF and BCF(Bio-concentration Factor)values in skin and eye tissue were the same and it was Ag>Al>As>B.It was Ag>Al>As>B in skeleton,Al>As>Ag>B in brain.HQ(Hazard Quotient)of Al in all tissues had carcinogenic risk level.展开更多
This study aims to investigate the capacity of <i>Chrysopogon</i> <i>nigritanus</i> to accumulate As from contaminated soils<i>.</i><b> </b>The experiment was conducted ...This study aims to investigate the capacity of <i>Chrysopogon</i> <i>nigritanus</i> to accumulate As from contaminated soils<i>.</i><b> </b>The experiment was conducted in a greenhouse. <i>C.</i> <i>nigritanus</i> was subjected to uncontaminated soil and As contaminated soil (50 mg/kg, 100 mg/kg and 150 mg/kg of As), for 180 days. Plant growth and biomass produced, concentration of As in soil and plant, bioaccumulation and transfer factors, as the location of As in tissues and cells of the plant have been determined. Plant growth decreased significantly with increasing of soil As concentration. <i>C.</i> <i>nigritanus</i> accumulated more As in roots biomass. The highest bioaccumulation factor values were found in contaminated soil at 50 mg As/kg (As 50), then contaminated soil at 100 mg As/kg (As 100) and contaminated soil at 150 mg As/kg (As 150). As was essentially fixed to the intracellular compartment of the roots, stems and leaves. In roots tissues, As was mainly retained in the rhizodermis and the pericycle. While in stems tissues, As was preferentially accumulated in the conductive bundles. In the leaves, the final destination of As was epidermis tissues.展开更多
Contamination of the food chain with heavy metals is considered as one of the major environmental pathways of human exposure to metals leading to potential health risks. This study aimed to investigate the concentrati...Contamination of the food chain with heavy metals is considered as one of the major environmental pathways of human exposure to metals leading to potential health risks. This study aimed to investigate the concentrations of heavy metals such as copper (Cu), zinc (Zn), chromium (Cr), nickel (Ni), and manganese (Mn) in agricultural soils and food crops (fruit, leaf, and root vegetables), and their associated health risks to the local population in selected southern districts of Khyber Pakhtunkhwa Province, Pakistan. The concentrations of the selected metals in soil varied over a wide range, in the following decreasing order: Mn 〉 Zn 〉 Cr 〉 Ni 〉 Cu. The bioaccunmlation of metals in vegetables was within the permissible risk limits, except for Cr which showed higher contamination in all the tested food crops. The trend of metal transfer factors for different vegetables was in the order of Cu 〉 Ni 〉 Cr 〉 Mn 〉 Zn, while the calculated daily intake of metals (DIM) in adults and children through consumption of food crops was in the decreasing order of Mn 〉 Zn 〉 Ni 〉 Cr 〉 Cu. The health risk index (HRI) values for the heavy metals for both adults and children were less than 1. Therefore, no significant health risk is anticipated for the local consumers through ingestion of these food crops.展开更多
OBJECTIVE:To investigate the effect of Soothing liver therapy on infertile women undergoing in vitro fertilization and embryo transfer(IVF-ET)and to explore its mechanism.METHODS:Fifty-eight women with tubal infertili...OBJECTIVE:To investigate the effect of Soothing liver therapy on infertile women undergoing in vitro fertilization and embryo transfer(IVF-ET)and to explore its mechanism.METHODS:Fifty-eight women with tubal infertility were randomized into two groups:30 in an experimental group treated with Xiaoyao powder(Shugan)plus gonadotropin-releasing hormone analog(GnRHa)/follicle-stimulating hormone(FSH)/human chorionic gonadotropin(hCG)and 28 in the control group who were treated with GnRHa/FSH/hCG only.The total gonadotropin(Gn)doses required,endometrial thickness,oocyte numbers,high quality embryo production rate and pregnancy rate of the two groups were compared.The concentration of growth differentiation factor-9(GDF-9)in follicular fluid was detected by western blotting and the expression of GDF-9 mRNA in granulosa cells was measured using reverse tran-scription-polymerase chain reaction amplification.RESULTS:In the experimental group,the Gn dose was significantly lower than that in the control group;the endometrial thickness,high quality embryo production and pregnancy rates were significantly higher and the expression of GDF-9 mRNA was also significantly higher than in the control group(all P<0.05).CONCLUSION:Shugan treatment can improve the pregnancy rate of women with tubal infertility;its mechanism is possibly related to the increased expression of GDF-9 in granulosa cells.展开更多
The receptor tyrosine kinase encoded by the MET gene plays an important role in various cellular processes such as growth,survival,migration and angiogenesis,and its abnormal activation is closely related to the occur...The receptor tyrosine kinase encoded by the MET gene plays an important role in various cellular processes such as growth,survival,migration and angiogenesis,and its abnormal activation is closely related to the occurrence and development of various tumors.This article reviews the recent advances in diagnosis and treatment of MET-variant digestive tract tumors.In terms of diagnosis,the application of next-generation sequencing technology and liquid biopsy technology makes the detection of MET variants more accurate and efficient,providing a reliable basis for individualized treatment.In terms of treatment,MET inhibitors such as crizotinib and cabotinib have shown good efficacy in clinical trials.In addition,the combination of immunotherapy and MET inhibitors also demonstrated potential synergies,further improving the therapeutic effect.However,the complexity and heterogeneity of drug resistance mechanisms are still one of the difficulties in current research.In the future,it is necessary to further deepen the understanding of the mechanism of MET variation and explore new combination treatment strategies to improve the overall survival rate and quality of life of patients.The diagnosis and treatment of MET-variant digestive tract tumors are moving towards precision and individualization,and have broad application prospects.展开更多
基金funded by the Innovation Fund Project for College Students of Rongchang Campus of Southwest University,Chongqing Basic Research program ( 2008BB5243)the Fundamental Research Funds for the Central Universities( XDJK2010C093)
文摘[ Objective] To extract non-specific transfer factors (TFs) from goose spleens and to detect the activity of the extracts. [Methodl The non-specific TFs were extracted crudely from goose spleens using the dialysis method, and the effects of the extracts on immunity were studied. [ Result] The extracts of goose TFs were transparent, light yellow and non-toxic. The extracts were at pH 6.72 and did not contain higher molecular weight proteins. The concentration of minor polypeptides was 23.78 ug/ml. The results of immunization test showed that the level of antibodies was higher in the geese inoculated with the inactivated vaccine against infections serositis and the extracts of TFs than in the control geese injected with normal saline. In addition, the level of antibodies was significantly higher in the geese only inoculated with inactivated vaccine than in the control geese. The results showed that the extracts of TFs from goose spleens could enhance immunity to a certain extent. [ Conclusion] The study pro- vides a theoretical basis and technical reference for further researches on the biological activity of non-specific TFs from goose spleens as well as for application of the extracts.
基金Projects BK2007145 supported by the Jiangsu Natural Science Foundation of China NCET-04-0454 by the Program for New Century Excellent Talentsin Universities
文摘In order to examine the factors which affect the range of heat transfer in earth surrounding subways, FLAC3D was adopted in this study to analyze these factors, under different conditions, in a systematic manner. When we compare these numerical tests, the results show that the main factors, affecting the heat transfer range are the thermal properties of the surrounding earth, the initial ground temperature and the temperature in the tunnel. The heat transfer coefficient between air and linings has little effect on the temperature distribution around the tunnel. The current results can provide a reference for improving the thermal environment in subways and optimizing the design of subwav ventilation and air conditioning.
基金Project (2009ZX07212-001-01) supported by the Key Project of National Natural Science Foundation for Water Pollution Control and RemediationProject (50925417) supported by the National Funds for Distinguished Young Scientists+1 种基金Project (50830301) supported by the National Natural Science Foundation of ChinaProject (51074191) supported by the National Natural Science Foundation of China
文摘Study was carried out to analyze the distribution and migration patterns,soil-to-plant transfer and potential health risks of chromium in soil-vegetable system in areas near a ferro-alloy manufactory in Hunan province.The results show that soils near sewer outlet,sewer channel and in control area are averaged 2 239.5,995.33 and 104.9 mg/kg,respectively.The total Cr has a relative accumulation in soil depth of 200-400 mm near the sewer outlet,mainly enriches in the surface layer(0-200 mm) near the sewer channel and decreases gradually in unpolluted soils.The differential concentration level of enrichment between layers is little.The results also indicate that the three vegetables of celery,lettuce and Chinese cabbage are able to convert the potentially toxic Cr(Ⅵ) species into the non-toxic Cr(Ⅲ) species,and the chromium contents in the edible parts of the vegetables are averaged 11.95 mg/kg.The transfer factors of the three vegetables follow the order:Chinese cabbage lettuce celery.The estimated total daily intake of chromium substantially exceeds the dietary allowable value,which may pose health risks to local population.
基金Supported by the National Natural Science Foundation of China(11472093 and21276056)
文摘Experiments and simulations on flow and heat transfer behavior of Therminol-55 liquid phase heat transfer fluid have been conducted in a ribbed tube with the outer diameter and inner diameter 25.0 and 20.0 mm,pitch and rib height of 4.5 and 1.0 mm.respectively.Experimental results show that the heat transfer and thermal performance of Therminol-55 liquid phase heat transfer fluid in the ribbed tube are considerably improved compared to those of the smooth tube.The Nusselt number increase with the increase of Reynolds number.The increase in heat transfer rate of the ribbed tube has a mean value of 2.24 times.Also,the pressure drop results reveal that the average friction factor of the ribbed tube is in a range of 2.4 and 2.8 times over the smooth tube.Numerical simulations of three-dimensional flow behavior of Therminol-55 liquid phase heat transfer fluid are carried out using three different turbulence models in the ribbed tube.The numerical results show that the heat transfer of ribbed tube is improved because vortices are generated behind ribs,which produce some disruptions to fluid flow and enhance heat transfer compared with smooth tube.The numerical results prove that the ribbed tube can improve heat transfer and fluid flow performances of Therminol liquid phase heat transfer fluid.
文摘In this paper, it is offered to use the method of modulated reflection for the measurementof complex transfer factor of a radome wall on various sites of its surface. The circuit of equipmentallowed to carry out of such measurement is given. The advantage of the given method in comparisonwith measurements on a gleam is shown. The results of the experimental research are given and theestimation of the accuracy of proposed method is considered.
基金supported by the National Natural Science Foundation of China(No.41877251).
文摘Experiments about heat transfer in the presence of a two-phase flow due to the condensation of a R1234yf refrigerant have been performed considering a smooth tube and two micro-fin tubes.The following experimental conditions have been considered:Condensation temperatures of 40℃,43℃ and 45℃,mass fluxes of 500–900 kg/(m^(2)·s),vapor qualities at the inlet and outlet of the heat transfer tube in the ranges 0.8–0.9 and 0.2–0.3,respectively.These tests have shown that:(1)The heat transfer coefficient increases with decreasing the condensation temperature and on increasing the mass flux;(2)The heat transfer coefficient inside the micro-fin tube is larger than that for the smooth tube;(3)The heat transfer enhancement factors for the micro-fin tube with a fin helical angle of 8°and 15°are 2.51–2.89 and 3.11–3.57,respectively;both are higher than the area increase ratio.These experimental results have been compared with correlations available in the literature:the Cavallini et al.correlation has the highest accuracy in predicting the heat transfer coefficient inside the smooth tube,the related percentage error and the average prediction error are±8%and 0.56%,respectively;for the micro-fin tube these become±25%and 6%,respectively.
文摘The activity concentrations of radionuclides, absorbed dose rate, excess lifetime cancer risk, and soil-to-plant transfer factor have been evaluated in soil and crop samples from Jalingo and Wukari Local Government Area of Taraba State, Nigeria. The activity concentrations were determined with the aid of High Purity Germanium detector. The absorbed dose and excess lifetime cancer risk were evaluated and forecasted for 60 years using the ResRad off-site model. The average activity concentration of <sup>40</sup>K, <sup>232</sup>Th, and <sup>238</sup>U in the soil samples were 633.13, 141.15, and 71.20 Bq·kg<sup>-1</sup> respectively, for the Jalingo study area, and while that of the Wukari study area was;199.21, 87.23, and 25.37 Bq·kg<sup>-1</sup> respectively. The average soil-to-plant transfer factors for <sup>40</sup>K, <sup>232</sup>Th, and <sup>238</sup>U were 0.51, 0.10, and 0.27 respectively for the Jalingo study area while that of Wukari are 0.40, 0.57, and 0.74 respectively. The mean annual effective dose equivalent for the study area is higher than the world average of 0.07 mS·vy<sup>-1</sup>. The excess lifetime cancer risk for the study areas has values that are higher than the safety limit. The ResRed model showed that direct radiation from the crops is the major contributor to excess cancer risk among other pathways. The radiological hazard indices reveal health risks to farmers, especially in the Jalingo area.
文摘In liquid-liquid systems, the substrates in the liquids are inaccessible to each other for the reaction. By adding a small quantity of phase transfer catalyst, the reaction can be made accessible and accelerated. The present study involves the phase transfer catalyzed oxidation of 2-methyl-l-butanol by quaternary ammonium permanganate (tricaprylyl methyl ammonium permanganate). The attempt was to compare the kinetics under homogeneous and heterogeneous conditions. Experiments were conducted in a batch reactor to determine the kinetics under homogeneous conditions. A baffled horosilicate agitated reactor was used to find the enhancement factor and the kinetics under heterogeneous conditions. The rate constants determined under both homogeneous and heterogeneous conditions agreed very weU. The oxidation was found to be first order with respect to each of the reactants, quaternary ammonium permanganate and the alcohol, resulting in an overall second order rate expression. Aliquat336 (tricaprylylmethylammonium chloride) was found to be the best compared with the other catalysts tested (triethylbenzylammonium chloride, tetrabutylammonium bromide, tetrabutylammonium iodide and tetrabutylammonium hydrogen sulfate) and it gave an enhancement factor of 9.8.
文摘Accumulation of heavy metals in agricultural soils is instigated by industrial and other human activities such as mining,smelting,cement-pollution,energy and fuel production,power transmission,traffic activities,intensive agriculture,sludge dumping and melting operations.Plants received heavy metals from soils through ionic exchange,redox reactions,precipitation-dissolution,and so on,which implies that the solubility of trace elements based on factors like minerals in the soil(carbonates,oxide,hydroxide etc.),soil organic matter(humic acids,fulvic acids,polysaccharides and organic acids),soil pH,redox potential,content,nutrient balance,other trace elements concentration in soil,physical and mechanical characteristics of soil,soil temperature and humidity,and so on.In this study,the soil-edible plant and soil-water Transfer Factor(TF)for various metals showed that the TF values differed slightly between the locations.On soil-edible plant transfer,the mean TF for different heavy metals in soil-edible plants decreased in the following order:As(0.6)mg/kg>Cd(0.1)mg/kg>Cr(0.06)mg/kg>Pb(0.003)mg/kg>Ni(0.001)mg/kg.The total TF for different locations decreases in the following order:Barkin Ladi(1.0)mg/kg>Jos South and Jos East(0.7)mg/kg>Bassa and Mangu(0.6)mg/kg.On soil-water transfer,the mean TF for different heavy metals in soil-edible plants decreased in the following order:Cd(0.001)mg/L>As(0.0007)mg/L>Cr(0.0005)mg/L>Pb(0.0001)mg/L and Ni(0.0001)mg/L.The total TF for different locations decreases in the following order:Jos South(0.003)mg/kg>Barkin Ladi,Bassa,Jos East and Mangu(0.002)mg/kg.Based on the findings of this study,it can be concluded that the water and edible plants in the study area are good for public consumption,even though,regular checking of heavy metals in the study area is recommended.
文摘Phytoremediation is a relatively new approach in remediating ecosystems contaminated by ecotoxic pollutants such as herbicides or heavy metals and especially cadmium (Cd). Certain indicators of phytoremediation, as plant growth, tolerance to Cd, and uptake, transfer factor (TF) and percent removal of Cd, were studied for 11 crops and 8 weed species in soil with varying levels of Cd (0-240 mg Cd kg" soil) under controlled environment. Cadmium accumulated mainly in roots (51%-86%, depending on the species), while a 14%-49% was transferred to shoots (except for four species) the concentration being positively related to Cd level in soil. Highest concentration in the above ground plant part was measured in sugarbeets (41-101 mg Cd kg-1 DW) followed by Bromus sterilis (75), Eruca sativa (32-82), Cichorium intibus (35-80), and maize (60 mg Cd kgl). Based on the results it is concluded that sugarbeets, maize, C. intibus, B. sterilis, E. sativa, Apium graveolens, and Vicia sativa seem to have a potential in remediating Cd contaminated soils.
文摘This study aims to assess the effective capacity of <i>Panicum</i><span> <i>maximum</i> </span>to accumulate cadmium (Cd), nickel (Ni) and lead (Pb). <i>P</i><span>. <i>maximum</i></span> observed in a greenhouse was subjected to 2 ppm of Cd, 50 ppm of Ni, 100 ppm of Pb contaminated soil and uncontaminated soil, </span></span><span><span><span style="font-family:"">for</span></span></span><span><span><span style="font-family:""> 120 days. Plant growth and biomass produced concentration of trace metals in soil and plant, bioaccumulation and transfer factors, location of potentially toxic elements in tissues and cells of plant ha</span></span></span><span><span><span style="font-family:"">ve</span></span></span><span><span><span style="font-family:""> been determined. Stem length and biomass produced by <i>P</i><span>. <i>maximum</i></span> were higher on the uncontaminated soil followed respectively by those of soil-contaminated by Pb, Cd and Ni. Bioaccumulation factors of trace metals were 8.93 (Pb), 8.47 (Ni) and 3.37 (Cd). Ni was more accumulated in shoot biomass (FT > 1), while Pb and Cd were concentrated in root biomass (FT </span></span></span><span><span><span style="font-family:""><</span></span></span><span><span><span style="font-family:""> 1). Pb is accumulated preferentially in endodermis (roots) and epidermis (leaves). As for Ni and Cd, they are concentrated in central cylinder of roots and in conductive bundles of leaves. At cellular level, Ni and Cd are mainly concentrated in intracellular compartments of leaves and roots, while Pb is strongly detected at cell walls.
文摘The role that a learner's native language plays in his or her second language acquisition (SLA) has been the focus of many researchers in the past few decades. The article provides a brief review of the literature on the importance and the factors of native language influence in SLA.
文摘Accumulation of metals in both sediments and Phragmites australis organs was studied. Samples were collected from seven stations located in Anzali wetland, Iran. The samples were analyzed by inductively coupled plasma mass spectrometry(ICP-MS). The results showed that concentration of the studied metals(except As and Cd) were higher in sediments than in P.australis organs. Metal accumulation was found to be signifi cantly(P <0.05) higher in roots than in above-ground organs of P.australis. The bioaccumulation factor(BAF) and the transfer factor(TF) also verifi ed the highest rate of metal accumulation in roots and their reduced mobility from roots to the above-ground organs. Pearson correlation coeffi cient showed signifi cant relationships between metal concentrations in sediments and those in plant organs. It should be pointed out that sediment and plant samples exhibited higher metal concentrations in eastern and central parts than in western and southern parts of the wetland. The mean concentrations of all studied elements(except for Fe, V and Al) were higher in these sediment samples than in the Earth's crust and shale. High accumulation of metals in P. australis organs(roots and shoots) is indicative of their high bioavailability in sediments of the wetland. The correlation between metal concentrations in sediments and in P. australis indicates that plant organs are good bioindicators of metal pollution in sediments of Anzali wetland.
文摘In this study, sixteen soil and vegetable samples from Tafila district were collected and analyzed from eight locations. Measurements of specific activity of natural gamma emitter radionuclides, 23SU and 235U, in these samples using gamma spectrometry, with the help of Genie 2000 software. Measurements were used to calculate the soil-vegetable transfer factor, and then the external radiation dose and internal radiation dose due to radioactivity of the ingested food. The specific activity of238U and 235U in soil were found to vary from (in Bq/kg): 26-575 and 1.4-35.5, respectively. The specific activity of 238U and 235U in vegetables were found to vary from (in Bq/kg): 0.019 to 0.632 and 0.0013-0.0375, respectively. The calculated transfer factor of Z3SU and Z35U range from 5.9 × 10^-4to 14.6 × 10^-4 for 238U and 4.9 × 10^-4 to 16.1 × 10^-4 for 235U. External absorbed dose rates were calculated to be in the range from 12.42 to 266.00 nGy/h. The annual effective dose was found to vary from 28.94 to 619.78 μSv/y. The annual internal effective dose due to 23SU and 23SU for fresh weights ofvegetablesl were found to vary from 0.9 × 10^-3 to 35.1 × 10^-3 μSv/y for 238U and 0.61 × 10^-4 to 17.62 × 10^-4 μSv/y for 235U.
文摘Clinical observation on 48 cases of stomach carcinoma pain indicated that acupuncture including filiform needle group and point-injection group had better therapeutic effects in treatment of stomach carcinoma pain when patient's mind was concentrated at the site of disease. After treatment for 2 months, the long-term effective rates of analgesia in both the filiform needle group and the point-injection group were similar to that in the western medicine group, all being about 81%. While the long-term markedly effective rates in the two groups were superior to that in the western medicine group. Life quality of the patients in all the groups were improved. The toxic action and side effects caused by chemotherapy were prevented, the high viscous state showed by indexes of blood rheology was improved, and the lowered Cu-Zu-SOD activity in erythrocytes in patients of stomach carcinoma was increased in the filiform needle group and the point-injection group. Based on the results of clinical study, we consider that acupuncture analgesic effect on stomach carcinoma is related to the increase of PLEK, improvement of cellular immune function and the elevation of life quality after acupuncture.
文摘In this study,the usage wastewater from secondary treatment in feeding fishes of Carassius gibelio species and suitability of the fishes for human food were evaluated.The metals(Ag,Al,As and B)in treated effluent and skeleton,skin,eyes and brain tissues of fishes were examined seasonally.It was found that treated effluent was not suitable for irrigation and aquaculture in terms of Al according to the Turkish standard values.According to annual averages the size order of Ag and B concentrations were skeleton>skin>eyes>brain and skeleton>skin>brain>eye respectively.Also,skin>brain>eyes>skeleton was for As and Al.TF(Transfer Factor)values of all metals examined were determined as>1 in the four tissues and the metals caused bioaccumulation because of treated effluent.Concentrations in muscles were found 7 to 6227 times higher than in water.The size order of TF and BCF(Bio-concentration Factor)values in skin and eye tissue were the same and it was Ag>Al>As>B.It was Ag>Al>As>B in skeleton,Al>As>Ag>B in brain.HQ(Hazard Quotient)of Al in all tissues had carcinogenic risk level.
文摘This study aims to investigate the capacity of <i>Chrysopogon</i> <i>nigritanus</i> to accumulate As from contaminated soils<i>.</i><b> </b>The experiment was conducted in a greenhouse. <i>C.</i> <i>nigritanus</i> was subjected to uncontaminated soil and As contaminated soil (50 mg/kg, 100 mg/kg and 150 mg/kg of As), for 180 days. Plant growth and biomass produced, concentration of As in soil and plant, bioaccumulation and transfer factors, as the location of As in tissues and cells of the plant have been determined. Plant growth decreased significantly with increasing of soil As concentration. <i>C.</i> <i>nigritanus</i> accumulated more As in roots biomass. The highest bioaccumulation factor values were found in contaminated soil at 50 mg As/kg (As 50), then contaminated soil at 100 mg As/kg (As 100) and contaminated soil at 150 mg As/kg (As 150). As was essentially fixed to the intracellular compartment of the roots, stems and leaves. In roots tissues, As was mainly retained in the rhizodermis and the pericycle. While in stems tissues, As was preferentially accumulated in the conductive bundles. In the leaves, the final destination of As was epidermis tissues.
基金supported by the Directorate of Science and Technology, Khyber Pakhtunkhwa, Pakistanthe Higher Education Commission, Islamabad, Pakistansupported by the NIEHS Superfund Research Program (No. ES04940)
文摘Contamination of the food chain with heavy metals is considered as one of the major environmental pathways of human exposure to metals leading to potential health risks. This study aimed to investigate the concentrations of heavy metals such as copper (Cu), zinc (Zn), chromium (Cr), nickel (Ni), and manganese (Mn) in agricultural soils and food crops (fruit, leaf, and root vegetables), and their associated health risks to the local population in selected southern districts of Khyber Pakhtunkhwa Province, Pakistan. The concentrations of the selected metals in soil varied over a wide range, in the following decreasing order: Mn 〉 Zn 〉 Cr 〉 Ni 〉 Cu. The bioaccunmlation of metals in vegetables was within the permissible risk limits, except for Cr which showed higher contamination in all the tested food crops. The trend of metal transfer factors for different vegetables was in the order of Cu 〉 Ni 〉 Cr 〉 Mn 〉 Zn, while the calculated daily intake of metals (DIM) in adults and children through consumption of food crops was in the decreasing order of Mn 〉 Zn 〉 Ni 〉 Cr 〉 Cu. The health risk index (HRI) values for the heavy metals for both adults and children were less than 1. Therefore, no significant health risk is anticipated for the local consumers through ingestion of these food crops.
基金Supported by the National Natural Science Foundation of China(No.81173294)
文摘OBJECTIVE:To investigate the effect of Soothing liver therapy on infertile women undergoing in vitro fertilization and embryo transfer(IVF-ET)and to explore its mechanism.METHODS:Fifty-eight women with tubal infertility were randomized into two groups:30 in an experimental group treated with Xiaoyao powder(Shugan)plus gonadotropin-releasing hormone analog(GnRHa)/follicle-stimulating hormone(FSH)/human chorionic gonadotropin(hCG)and 28 in the control group who were treated with GnRHa/FSH/hCG only.The total gonadotropin(Gn)doses required,endometrial thickness,oocyte numbers,high quality embryo production rate and pregnancy rate of the two groups were compared.The concentration of growth differentiation factor-9(GDF-9)in follicular fluid was detected by western blotting and the expression of GDF-9 mRNA in granulosa cells was measured using reverse tran-scription-polymerase chain reaction amplification.RESULTS:In the experimental group,the Gn dose was significantly lower than that in the control group;the endometrial thickness,high quality embryo production and pregnancy rates were significantly higher and the expression of GDF-9 mRNA was also significantly higher than in the control group(all P<0.05).CONCLUSION:Shugan treatment can improve the pregnancy rate of women with tubal infertility;its mechanism is possibly related to the increased expression of GDF-9 in granulosa cells.
基金2023 Anhui Province Clinical Medical Research Transformation Project,No.202304295107020016.
文摘The receptor tyrosine kinase encoded by the MET gene plays an important role in various cellular processes such as growth,survival,migration and angiogenesis,and its abnormal activation is closely related to the occurrence and development of various tumors.This article reviews the recent advances in diagnosis and treatment of MET-variant digestive tract tumors.In terms of diagnosis,the application of next-generation sequencing technology and liquid biopsy technology makes the detection of MET variants more accurate and efficient,providing a reliable basis for individualized treatment.In terms of treatment,MET inhibitors such as crizotinib and cabotinib have shown good efficacy in clinical trials.In addition,the combination of immunotherapy and MET inhibitors also demonstrated potential synergies,further improving the therapeutic effect.However,the complexity and heterogeneity of drug resistance mechanisms are still one of the difficulties in current research.In the future,it is necessary to further deepen the understanding of the mechanism of MET variation and explore new combination treatment strategies to improve the overall survival rate and quality of life of patients.The diagnosis and treatment of MET-variant digestive tract tumors are moving towards precision and individualization,and have broad application prospects.