The difference of gene expression profile changes in Barrett's esophagus (BE) and cardia intestinal metaplasia (CIM) epithelium was studied and the novel associated genes were screened in the early stage by cDNA ...The difference of gene expression profile changes in Barrett's esophagus (BE) and cardia intestinal metaplasia (CIM) epithelium was studied and the novel associated genes were screened in the early stage by cDNA microarray. The cDNA retro-transcribed from equal quantity mRNA from BE and CIM epithelial tissues were labeled with Cy3 and Cy5 fluorescence as probes. The mixed probe was hybridized with three pieces BiostarH-40s double dot human whole gene chip. The chips were scanned with a ScanArray 4000. The acquired images were analyzed using GenePix Pro 3.0 software. It was found a total of 141 genes were screened out that exhibited differentially expression more than 2 times in all three chips. It was identified that in gene expression profiles of BE, 74 genes were up-regulated and 67 down-regulated as compared with CIM. The comparison between the difference of gene expression profile changes in BE and CIM epithelia revealed that there existed the difference between BE and CIM at gene level. 141 genes with the expression more than two time were probably related to the occurrence and development of BE and the promotion or progress in adenocarcinoma.展开更多
Objective: The aim of this study was to investigate the characteristics of gene changes from Barrett's esophagus (BE) to esophageal adenocarcinoma by cDNA microarray. Methods: The cDNA retro-transcribed from equa...Objective: The aim of this study was to investigate the characteristics of gene changes from Barrett's esophagus (BE) to esophageal adenocarcinoma by cDNA microarray. Methods: The cDNA retro-transcribed from equal quantity mRNA from esophageal carcinoma and BE tissues as well as control normal epithelium of esophagus which were from one patient with esophageal adenocarcinoma were labeled with Cy5 and Cy3 fluorescence as probes. The mixed probes were hybridized with two pieces gene chip respectively. It was scanned by laser scanner Scan Array 4000. The acquired images were analyzed by software GenePix Pro 3.0. Results: A total of 214 genes were screened out which expression levels were more than 2 times in hybridization of esophageal adenocarcinoma vs normal epithelium of esophagus, whereas 90 genes in hybridization of BE vs normal epithelium. A parallel comparison among these two gene profiles showed that a total of 45 genes with 24 downregulation and 21 up-regulation which expression levels were more than 2 times between the BE and the esophageal adenocarcinoma. Among these, there were 27 genes with 18 downregulafion and 9 up-regulation which implicated the tendencies progressing from BE to esophageal adenocarcinoma. Conclusion: These genes or their products which implicate the tendencies can be chosen as indicators of carcinogenesis with high risk index for BE.展开更多
Sb<sub>2</sub>S<sub>3</sub> has gained tremendous research recently for thin film solar cell absorber material because of their easy synthesis, unique electrical and optical properties. The sto...Sb<sub>2</sub>S<sub>3</sub> has gained tremendous research recently for thin film solar cell absorber material because of their easy synthesis, unique electrical and optical properties. The stoichiometry and composition of electroless Sb<sub>2</sub>S<sub>3</sub> thin films were analyzed using XPS depth profile studies. The surface layers were found nearly stoichiometric. On the other hand, the inner layer was rich in antimony composition making it more conductive electrically.展开更多
Two hundred and fifty single first-order Arrhenius reactions are simulated to generate S2 pyrograms at three heating rates 25,15,and 5°C·min-1.The activation energy(E)and pre-exponential factor(A)of the reac...Two hundred and fifty single first-order Arrhenius reactions are simulated to generate S2 pyrograms at three heating rates 25,15,and 5°C·min-1.The activation energy(E)and pre-exponential factor(A)of the reactions simulated follow a long-established trend of those variable values displayed by shales and kerogens.The characteristics of the transformation fraction(TF)profiles(product generation window temperatures)of the simulated single reactions are compared to the TF profiles of recorded shale pyrograms generated by multiple reactions with different E-A values lying near the defined E-A trend.Important similarities and differences are observed between the TF profile values of the two datasets.The similarities support the spread of E-A values involved in shale pyrogram best fits.The differences are most likely explained by the complexity of the multiple kerogen first-order and second-order reactions contributing to the recorded shale pyrograms versus the simplicity and crispness of the single first-order reactions simulated.The results also justify the validity of using the previously described“variable E-A pyrogram-fitting method”of multi-heating-rate shale pyrograms enabling optimizers to choose multiple reactions from an unlimited range of E-A values.In contrast,further doubt is cast on the validity of the constant-A pyrogram-fitting method used by the Easy%Ro technique,in that a distribution of reactions with a single A value is unlikely to represent the complex variety of kerogen macerals observed in shale formations.TF profiles generated by the variable E-A pyrogram-fitting method lie close to the established E-A trend and are likely to provide more realistic TF generation window temperatures than TF profiles generated by the constant-A pyrogram-fitting method.展开更多
The development of numerical models able to compute the wheel and rail profile wear is essential to improve the scheduling of maintenance operations required to restore the original profile shapes.This work surveys th...The development of numerical models able to compute the wheel and rail profile wear is essential to improve the scheduling of maintenance operations required to restore the original profile shapes.This work surveys the main numerical models in the literature for the evaluation of the uniform wear of wheel and rail profiles.The standard structure of these tools includes a multibody simulation of the wheel-track coupled dynamics and a wear module implementing an experimental wear law.Therefore,the models are classified according to the strategy adopted for the worn profile update,ranging from models performing a single computation to models based on an online communication between the dynamic and wear modules.Nevertheless,the most common strategy nowadays relies on an iteration of dynamic simulations in which the profiles are left unchanged,with co-simulation techniques often adopted to increase the computational performances.Work is still needed to improve the accuracy of the current models.New experimental campaigns should be carried out to obtain refined wear coefficients and models,while strategies for the evaluation of both longitudinal and transversal wear,also considering the effects of tread braking,should be implemented to obtain accurate damage models.展开更多
AIM To determine whether and to what extent the gut microbiome is involved in regulating racial disparity in colorectal cancer(CRC). METHODS All patients were recruited and experiments were performed in accordance wit...AIM To determine whether and to what extent the gut microbiome is involved in regulating racial disparity in colorectal cancer(CRC). METHODS All patients were recruited and experiments were performed in accordance with the relevant guidelines and regulations by the Institutional Review Boards (IRB), committees of the John D. Dingell VAMC and Wayne State University guidelines. African American (AA) and Caucasian American (CA) patients were scheduled for an outpatient screening for colonoscopy, and no active malignancy volunteer patients were doubly consented, initially by the gastroenterologist and later by the study coordinator, for participation in the study. The gut microbial communities in colonic effluents from AAs and CAs were examined using 16 sRNA profiling, and bacterial identifications were validated by performing SYBR-based Real Time PCR. For metagenomic analysis to characterize the microbial communities, multiple software/tools were used, including Metastats and R statistical software.RESULTS It is generally accepted that the incidence and mortality of CRC is higher in AAs than in CAs. However, the reason for this disparity is not well understood. We hypothesize that the gut microbiome plays a role in regulating this disparity. Indeed, we found significant differences in species richness and diversity between AAs and CAs. Bacteroidetes was more abundant in AAs than in CAs. In particular, the pro-inflammatory bacteria Fusobacterium nucleatum and Enterobacter species were significantly higher in AAs, whereas probiotic Akkermansia muciniphila and Bifidobacterium were higher in CAs. The polyphyletic Clostridia class showed a divergent pattern, with Clostridium XI elevated in AAs, and Clostridium IV, known for its beneficial function, higher in CAs. Lastly, the AA group had decreased microbial diversity overall in comparison to the CA group. In summary, there were significant differences in pro-inflammatory bacteria and microbial diversity between AA and CA, which may help explain the CRC disparity between groups.CONCLUSION Our current investigation, for the first time, demonstrates microbial dysbiosis between AAs and CAs, which could contribute to the racial disparity of CRC.展开更多
This study introduces three typical models on equilibrium beach profile, and discusses the application limitations of these models. Then this study examines the selections for applying these models on different coasta...This study introduces three typical models on equilibrium beach profile, and discusses the application limitations of these models. Then this study examines the selections for applying these models on different coastal segments of a headland-bay beach in west Guangdong, South China, and explores the physical significances of those parameters in the models. The results indicate that:(1) Bodge's model is more in line with the equilibrium beach profile of the tangential or transitional segment, whereas Lee's model is more consistent with the shadow profile;(2) most of the parameters in three models have clear physical significances in accordance with the actual characteristics of this headland-bay beach; and(3) both the selections for the equilibrium beach profile from different segments and significances of most of the parameters in three models are in essence correlated with the morphodynamic states at various coastal locations.展开更多
In this study, an Alzheimer's disease model was established in rats through stereotactic injection of condensed amyloid beta 1-40 into the bilateral hippocampus, and the changes of gene expression profile in the hipp...In this study, an Alzheimer's disease model was established in rats through stereotactic injection of condensed amyloid beta 1-40 into the bilateral hippocampus, and the changes of gene expression profile in the hippocampus of rat models and sham-operated rats were compared by genome expression profiling analysis. Results showed that the expression of 50 genes was significantly up-regulated (fold change 〉 2), while 21 genes were significantly down-regulated in the hippocampus of Alzheimer's disease model rats (fold change 〈 0.5) compared with the sham-operation group. The differentially expressed genes are involved in many functions, such as brain nerve system development, neuronal differentiation and functional regulation, cellular growth, differentiation and apoptosis, synaptogenesis and plasticity, inflammatory and immune responses, ion channels/transporters, signal transduction, cell material/energy metabolism. Our findings indicate that several genes were abnormally expressed in the metabolic and signal transduction pathways in the hippocampus of amyloid beta 1 40-induced rat model of Alzheimer's disease, thereby affecting the hippocampal and brain functions.展开更多
By use of S wave information from three component records of wide angle reflection/refraction Beijing Fengzhen DSS profile (340.0 km) and its adjacent area, several main S wave phases (wave groups) of the crust a...By use of S wave information from three component records of wide angle reflection/refraction Beijing Fengzhen DSS profile (340.0 km) and its adjacent area, several main S wave phases (wave groups) of the crust and the top of upper mantle have been picked up and identified with digital processing technique. With reference to the results from P wave interpretation, 2 D structures, including S wave velocity vS and Poisson ratio μ , are calculated. After a comprehensive study with information from near vertical reflection, geology and other geophysical explorations, the deep structural configuration of this region is presented and relevant inferences are drawn from the above result: crustal thickness along the profile tends to increase westwards, from 35.0 km at Shunyi to 42.0 km at Fengzhen; there exist three low velocity bodies in the lower crust east of Yanqing, in the middle crust below Yanqing Zhuolu and in the upper crust west of Tianzhen, respectively; from east to west, there is also a crust mantle transitional zone about 5.0~9.0 km thick; in most parts of the region, μ value is 0.25 in the upper and middle crust, 0.27 in the lower crust and 0.28 on top of the upper mantle, indicating that the upper and middle crust is characterized by brittleness, and the lower crust and top of upper mantle is characterized by ductility; between Yanqing Zhuolu, the low μ values of the upper crust suggest that cracks (or pores) grow in the rock masses which present a dry (or gas filled) state, while the high μ values in the middle crust may reflect a fluid filled (or partially fusion) state of the rock masses. On the basis of the characteristics of phases and lateral variation features of μ values, several deep seated faults in this region are ascertained. Most earthquakes occurred near these faults where μ values vary significantly, and concentrate in the brittle rock masses with low μ values.展开更多
In order to search for intensity fluctuations on the HCN(1-0) and HCO+(1-0) line pro- files, which could arise due to possible small-scale inhomogeneous structure, long-term observations of high-mass star-forming...In order to search for intensity fluctuations on the HCN(1-0) and HCO+(1-0) line pro- files, which could arise due to possible small-scale inhomogeneous structure, long-term observations of high-mass star-forming cores S140 and S199 were carried out. The data were processed by the Fourier filtering method. Line temperature fluctuations that exceed the noise level were detected. Assuming the cores consist of a large number of randomly moving small thermal fragments, the total number of frag- ments is - 4 × 106 for the region with linear size - 0.1 pc in S140 and - 106 for the region with linear size - 0.3 pc in S 199. Physical parameters of fragments in S 140 were obtained from detailed modeling of the HCN emission in the framework of the clumpy cloud model.展开更多
Objective: To analyze the differential expression genes (DEGs) between Barrett’s esophagus (BE) and normal esophagus mucosa and explore the target genes related to the development and progression of BE. Methods: The ...Objective: To analyze the differential expression genes (DEGs) between Barrett’s esophagus (BE) and normal esophagus mucosa and explore the target genes related to the development and progression of BE. Methods: The total RNAs of matched BE and normal esophagus mucosa of BE patients were isolated using one step Trizol method. Matched RNAs were qualified using 10 g/L agarose gel electrophoresis. cRNAs were synthesized, fluorescence labeled and purified after total RNAs were purified. The RNAs of BE and normal esophagus mucosa were hybridized with Agilent oligomicroarray (30 968 probes). The fluorescence intensity features were detected by Agilent scanner and quantified by feature extraction software. Results: (1) The total RNA, reverse transcription product and fluorescence labeled cRNA were all of high quality; (2) There were 142 up-regulated genes and 284 down-regulated genes among 2-fold DEGs. Conclusion: Microarray-based studies are feasible in endoscopically obtained tissues. Many BE-associated genes are screened by the high-throughput gene chip. The development and progression of BE is a complicated process involving multiple genes and multiple procedures, and functional study of these genes may help to identify the key genes or pathways involved in the pathogenesis and development of BE.展开更多
为降低变速箱的振动噪声,提高整车噪声、振动与声振粗糙度(noise vibration harshness,NVH)性能,通过变速箱下线台架(end of line,EOL)振动测试和整车NVH测试,对比分析正常齿廓齿轮、带S形齿廓的齿轮对整车NVH性能的影响。EOL测试结果表...为降低变速箱的振动噪声,提高整车噪声、振动与声振粗糙度(noise vibration harshness,NVH)性能,通过变速箱下线台架(end of line,EOL)振动测试和整车NVH测试,对比分析正常齿廓齿轮、带S形齿廓的齿轮对整车NVH性能的影响。EOL测试结果表明:装配S形齿廓齿轮的变速箱的振动加速度级明显高于正常齿廓齿轮变速箱,尤其在48阶次处增幅最大。整车NVH测试结果表明,S形齿廓齿轮在发动机舱及车内的声压级分别增大12、7 dB。实际加工制造验证结果表明,正确设定齿轮加工珩磨轮寿命可以有效消除齿廓的S形波动,改善变速箱及整车的NVH性能。展开更多
文摘The difference of gene expression profile changes in Barrett's esophagus (BE) and cardia intestinal metaplasia (CIM) epithelium was studied and the novel associated genes were screened in the early stage by cDNA microarray. The cDNA retro-transcribed from equal quantity mRNA from BE and CIM epithelial tissues were labeled with Cy3 and Cy5 fluorescence as probes. The mixed probe was hybridized with three pieces BiostarH-40s double dot human whole gene chip. The chips were scanned with a ScanArray 4000. The acquired images were analyzed using GenePix Pro 3.0 software. It was found a total of 141 genes were screened out that exhibited differentially expression more than 2 times in all three chips. It was identified that in gene expression profiles of BE, 74 genes were up-regulated and 67 down-regulated as compared with CIM. The comparison between the difference of gene expression profile changes in BE and CIM epithelia revealed that there existed the difference between BE and CIM at gene level. 141 genes with the expression more than two time were probably related to the occurrence and development of BE and the promotion or progress in adenocarcinoma.
文摘Objective: The aim of this study was to investigate the characteristics of gene changes from Barrett's esophagus (BE) to esophageal adenocarcinoma by cDNA microarray. Methods: The cDNA retro-transcribed from equal quantity mRNA from esophageal carcinoma and BE tissues as well as control normal epithelium of esophagus which were from one patient with esophageal adenocarcinoma were labeled with Cy5 and Cy3 fluorescence as probes. The mixed probes were hybridized with two pieces gene chip respectively. It was scanned by laser scanner Scan Array 4000. The acquired images were analyzed by software GenePix Pro 3.0. Results: A total of 214 genes were screened out which expression levels were more than 2 times in hybridization of esophageal adenocarcinoma vs normal epithelium of esophagus, whereas 90 genes in hybridization of BE vs normal epithelium. A parallel comparison among these two gene profiles showed that a total of 45 genes with 24 downregulation and 21 up-regulation which expression levels were more than 2 times between the BE and the esophageal adenocarcinoma. Among these, there were 27 genes with 18 downregulafion and 9 up-regulation which implicated the tendencies progressing from BE to esophageal adenocarcinoma. Conclusion: These genes or their products which implicate the tendencies can be chosen as indicators of carcinogenesis with high risk index for BE.
文摘Sb<sub>2</sub>S<sub>3</sub> has gained tremendous research recently for thin film solar cell absorber material because of their easy synthesis, unique electrical and optical properties. The stoichiometry and composition of electroless Sb<sub>2</sub>S<sub>3</sub> thin films were analyzed using XPS depth profile studies. The surface layers were found nearly stoichiometric. On the other hand, the inner layer was rich in antimony composition making it more conductive electrically.
文摘Two hundred and fifty single first-order Arrhenius reactions are simulated to generate S2 pyrograms at three heating rates 25,15,and 5°C·min-1.The activation energy(E)and pre-exponential factor(A)of the reactions simulated follow a long-established trend of those variable values displayed by shales and kerogens.The characteristics of the transformation fraction(TF)profiles(product generation window temperatures)of the simulated single reactions are compared to the TF profiles of recorded shale pyrograms generated by multiple reactions with different E-A values lying near the defined E-A trend.Important similarities and differences are observed between the TF profile values of the two datasets.The similarities support the spread of E-A values involved in shale pyrogram best fits.The differences are most likely explained by the complexity of the multiple kerogen first-order and second-order reactions contributing to the recorded shale pyrograms versus the simplicity and crispness of the single first-order reactions simulated.The results also justify the validity of using the previously described“variable E-A pyrogram-fitting method”of multi-heating-rate shale pyrograms enabling optimizers to choose multiple reactions from an unlimited range of E-A values.In contrast,further doubt is cast on the validity of the constant-A pyrogram-fitting method used by the Easy%Ro technique,in that a distribution of reactions with a single A value is unlikely to represent the complex variety of kerogen macerals observed in shale formations.TF profiles generated by the variable E-A pyrogram-fitting method lie close to the established E-A trend and are likely to provide more realistic TF generation window temperatures than TF profiles generated by the constant-A pyrogram-fitting method.
文摘The development of numerical models able to compute the wheel and rail profile wear is essential to improve the scheduling of maintenance operations required to restore the original profile shapes.This work surveys the main numerical models in the literature for the evaluation of the uniform wear of wheel and rail profiles.The standard structure of these tools includes a multibody simulation of the wheel-track coupled dynamics and a wear module implementing an experimental wear law.Therefore,the models are classified according to the strategy adopted for the worn profile update,ranging from models performing a single computation to models based on an online communication between the dynamic and wear modules.Nevertheless,the most common strategy nowadays relies on an iteration of dynamic simulations in which the profiles are left unchanged,with co-simulation techniques often adopted to increase the computational performances.Work is still needed to improve the accuracy of the current models.New experimental campaigns should be carried out to obtain refined wear coefficients and models,while strategies for the evaluation of both longitudinal and transversal wear,also considering the effects of tread braking,should be implemented to obtain accurate damage models.
基金Supported by Department of Veteran Affairs,No.1I101BX001927National Institutes of Health,No.1R21CA175916
文摘AIM To determine whether and to what extent the gut microbiome is involved in regulating racial disparity in colorectal cancer(CRC). METHODS All patients were recruited and experiments were performed in accordance with the relevant guidelines and regulations by the Institutional Review Boards (IRB), committees of the John D. Dingell VAMC and Wayne State University guidelines. African American (AA) and Caucasian American (CA) patients were scheduled for an outpatient screening for colonoscopy, and no active malignancy volunteer patients were doubly consented, initially by the gastroenterologist and later by the study coordinator, for participation in the study. The gut microbial communities in colonic effluents from AAs and CAs were examined using 16 sRNA profiling, and bacterial identifications were validated by performing SYBR-based Real Time PCR. For metagenomic analysis to characterize the microbial communities, multiple software/tools were used, including Metastats and R statistical software.RESULTS It is generally accepted that the incidence and mortality of CRC is higher in AAs than in CAs. However, the reason for this disparity is not well understood. We hypothesize that the gut microbiome plays a role in regulating this disparity. Indeed, we found significant differences in species richness and diversity between AAs and CAs. Bacteroidetes was more abundant in AAs than in CAs. In particular, the pro-inflammatory bacteria Fusobacterium nucleatum and Enterobacter species were significantly higher in AAs, whereas probiotic Akkermansia muciniphila and Bifidobacterium were higher in CAs. The polyphyletic Clostridia class showed a divergent pattern, with Clostridium XI elevated in AAs, and Clostridium IV, known for its beneficial function, higher in CAs. Lastly, the AA group had decreased microbial diversity overall in comparison to the CA group. In summary, there were significant differences in pro-inflammatory bacteria and microbial diversity between AA and CA, which may help explain the CRC disparity between groups.CONCLUSION Our current investigation, for the first time, demonstrates microbial dysbiosis between AAs and CAs, which could contribute to the racial disparity of CRC.
基金financially supported by the National Natural Science Foundation of China(Grant No.41301005)Postdoctoral Science Foundation of China(Grant No.2014M552118)
文摘This study introduces three typical models on equilibrium beach profile, and discusses the application limitations of these models. Then this study examines the selections for applying these models on different coastal segments of a headland-bay beach in west Guangdong, South China, and explores the physical significances of those parameters in the models. The results indicate that:(1) Bodge's model is more in line with the equilibrium beach profile of the tangential or transitional segment, whereas Lee's model is more consistent with the shadow profile;(2) most of the parameters in three models have clear physical significances in accordance with the actual characteristics of this headland-bay beach; and(3) both the selections for the equilibrium beach profile from different segments and significances of most of the parameters in three models are in essence correlated with the morphodynamic states at various coastal locations.
基金sponsored by the National Natural Science Foundation of China,No. 30973779
文摘In this study, an Alzheimer's disease model was established in rats through stereotactic injection of condensed amyloid beta 1-40 into the bilateral hippocampus, and the changes of gene expression profile in the hippocampus of rat models and sham-operated rats were compared by genome expression profiling analysis. Results showed that the expression of 50 genes was significantly up-regulated (fold change 〉 2), while 21 genes were significantly down-regulated in the hippocampus of Alzheimer's disease model rats (fold change 〈 0.5) compared with the sham-operation group. The differentially expressed genes are involved in many functions, such as brain nerve system development, neuronal differentiation and functional regulation, cellular growth, differentiation and apoptosis, synaptogenesis and plasticity, inflammatory and immune responses, ion channels/transporters, signal transduction, cell material/energy metabolism. Our findings indicate that several genes were abnormally expressed in the metabolic and signal transduction pathways in the hippocampus of amyloid beta 1 40-induced rat model of Alzheimer's disease, thereby affecting the hippocampal and brain functions.
文摘By use of S wave information from three component records of wide angle reflection/refraction Beijing Fengzhen DSS profile (340.0 km) and its adjacent area, several main S wave phases (wave groups) of the crust and the top of upper mantle have been picked up and identified with digital processing technique. With reference to the results from P wave interpretation, 2 D structures, including S wave velocity vS and Poisson ratio μ , are calculated. After a comprehensive study with information from near vertical reflection, geology and other geophysical explorations, the deep structural configuration of this region is presented and relevant inferences are drawn from the above result: crustal thickness along the profile tends to increase westwards, from 35.0 km at Shunyi to 42.0 km at Fengzhen; there exist three low velocity bodies in the lower crust east of Yanqing, in the middle crust below Yanqing Zhuolu and in the upper crust west of Tianzhen, respectively; from east to west, there is also a crust mantle transitional zone about 5.0~9.0 km thick; in most parts of the region, μ value is 0.25 in the upper and middle crust, 0.27 in the lower crust and 0.28 on top of the upper mantle, indicating that the upper and middle crust is characterized by brittleness, and the lower crust and top of upper mantle is characterized by ductility; between Yanqing Zhuolu, the low μ values of the upper crust suggest that cracks (or pores) grow in the rock masses which present a dry (or gas filled) state, while the high μ values in the middle crust may reflect a fluid filled (or partially fusion) state of the rock masses. On the basis of the characteristics of phases and lateral variation features of μ values, several deep seated faults in this region are ascertained. Most earthquakes occurred near these faults where μ values vary significantly, and concentrate in the brittle rock masses with low μ values.
基金support of the RFBR grants(projects 15–02–06098,16–02–00761 and18–02–00660)support of the Russian Science Foundation grant(project 17–12–01256)
文摘In order to search for intensity fluctuations on the HCN(1-0) and HCO+(1-0) line pro- files, which could arise due to possible small-scale inhomogeneous structure, long-term observations of high-mass star-forming cores S140 and S199 were carried out. The data were processed by the Fourier filtering method. Line temperature fluctuations that exceed the noise level were detected. Assuming the cores consist of a large number of randomly moving small thermal fragments, the total number of frag- ments is - 4 × 106 for the region with linear size - 0.1 pc in S140 and - 106 for the region with linear size - 0.3 pc in S 199. Physical parameters of fragments in S 140 were obtained from detailed modeling of the HCN emission in the framework of the clumpy cloud model.
文摘Objective: To analyze the differential expression genes (DEGs) between Barrett’s esophagus (BE) and normal esophagus mucosa and explore the target genes related to the development and progression of BE. Methods: The total RNAs of matched BE and normal esophagus mucosa of BE patients were isolated using one step Trizol method. Matched RNAs were qualified using 10 g/L agarose gel electrophoresis. cRNAs were synthesized, fluorescence labeled and purified after total RNAs were purified. The RNAs of BE and normal esophagus mucosa were hybridized with Agilent oligomicroarray (30 968 probes). The fluorescence intensity features were detected by Agilent scanner and quantified by feature extraction software. Results: (1) The total RNA, reverse transcription product and fluorescence labeled cRNA were all of high quality; (2) There were 142 up-regulated genes and 284 down-regulated genes among 2-fold DEGs. Conclusion: Microarray-based studies are feasible in endoscopically obtained tissues. Many BE-associated genes are screened by the high-throughput gene chip. The development and progression of BE is a complicated process involving multiple genes and multiple procedures, and functional study of these genes may help to identify the key genes or pathways involved in the pathogenesis and development of BE.