N-type Si-based type-Ⅰ clathrates with different Ga content were synthesized by combining the solid-state reaction method,melting method and spark plasma sintering （SPS） method.The effects of Ga composition on high...N-type Si-based type-Ⅰ clathrates with different Ga content were synthesized by combining the solid-state reaction method,melting method and spark plasma sintering （SPS） method.The effects of Ga composition on high temperature thermoelectric transport properties were investigated.The results show that at room temperature,the carrier concentration decreases, while the carrier mobility increases slightly with increasing Ga content.The Seebeck coefficient increases with increasing Ga content. Among all the samples,Ba7.93Ga17.13Si28.72exhibits higher Seebeck coefficient than the others and reaches -135μV·K^-1 at 1000 K.The sample prepared by this method exhibits very high electrical conductivity,and reaches 1.95x 10^5 S·m^-1 for Ba8.01Ga16.61Si28.93 at room temperature.The thermal conductivity of all samples is almost temperature independent in the temperature range of 300-1000 K,indicating the behaviour of a typical metal.The maximum ZT value of 0.75 is obtained at 1000 K for the compound Ba7.93Ga17.13Si28.72.展开更多
The relationship between NaCl concentration and the phase change behavior of microemulsion of anionic surfactant was characterized by the salinity scan experiments.The wettability of WinsorⅠtype surfactant solution(W...The relationship between NaCl concentration and the phase change behavior of microemulsion of anionic surfactant was characterized by the salinity scan experiments.The wettability of WinsorⅠtype surfactant solution(WⅠsolution)and the effect of NaCL concentration on phase change behavior of WⅠsolution and imbibition in oil-wet porous media were investigated by microfluidic experiments in this study.The WⅠsolution and WinsorⅠtype microemulsion are similar in wetting phase with stronger wettability than other phases.Two main mechanisms of WⅠsolution enhancing imbibitions recovery in oil wet porous media are the wetting phase drive and residual oil solubilization.Under the salinity condition of WinsorⅠtype microemulsion,the NaCl concentration has strong impact on the imbibition mechanism of WⅠsolution,the higher the NaCl concentration,the complex the imbibition process and the higher the imbibition efficiency will be.The NaCl concentration has strong impact on the solubilization ability to oil of the WⅠsolution,the higher the NaCl concentration,the stronger the solubility of the WⅠsolution to residual oil will be.展开更多
AIM To evaluate the incidence of lymph node metastasis （LNM） and its risk factors in patients with Siewert type Ⅰ and type Ⅱ pT1 adenocarcinomas.METHODS We enrolled 85 patients [69 men, 16 women; median age （ra...AIM To evaluate the incidence of lymph node metastasis （LNM） and its risk factors in patients with Siewert type Ⅰ and type Ⅱ pT1 adenocarcinomas.METHODS We enrolled 85 patients [69 men, 16 women; median age （range）, 67 （38-84） years] who had undergone esophagectomy or proximal gastrectomy for Siewert type Ⅰ and type Ⅱ pT1 adenocarcinomas. Predictive risk factors of LNM included age, sex, location of the tumor center, confirmed Barrett’s esophageal adenocarcinoma, tumor size, macroscopic tumor type, pathology, invasion depth, presence of ulceration, and lymphovascular invasion. Multivariate logistic regression analysis was used to identify factors predicting LNM. We also evaluated the frequencies of LNM for Siewert type Ⅰ and type Ⅱ pT1 adenocarcinomas in meta-data analysis.RESULTSLNMs were found in 11 out of 85 patients （12.9%, 95%CI： 5.8-20.0）. Only 1 of the 15 patients （6.6%, 95%CI： 0.0-19.2） who had a final diagnosis of pT1a adenocarcinoma had a positive LNM, whereas 10 of the 70 patients （14.2%, 95%CI： 6.0-22.4） with a final diagnosis of pT1b adenocarcinoma had positive LNM. Furthermore, only one of the 30 patients （3.3%, 95%CI： 0.0-9.7） with a tumor invasion depth within 500 μm from muscularis mucosae had positive LNM. Poor differentiation and lymphovascular invasion were independently associated with a risk of LNM. In meta-data analysis, 12 of the 355 patients （3.3%, 95%CI： 1.5-5.2） who had a final diagnosis of pT1a adenocarcinoma had a positive LNM, whereas 91 of the 438 patients （20.7%, 95%CI： 16.9-24.5） with a fnal diagnosis of pT1b adenocarcinoma had positive LNM.CONCLUSIONWe consider endoscopic submucosal dissection （ESD） is suitable for patients with Siewert type Ⅰ and type Ⅱ T1a adenocarcinomas. For patients with T1b adenocarcinoma, especially invasion depth is within 500 μm from muscularis mucosae with no other risk factor for LNM, diagnostic ESD could be a treatment option according to the overall status of patients and the presence of comorbidities.展开更多
In this study, serum concentrations of carboxyterminal propeptide of type Ⅰ collagen(PICP) and carboxyterminal cross-linked telopeptide of type Ⅰ collagen (ICTP), which represent the rates of synthesis and degradati...In this study, serum concentrations of carboxyterminal propeptide of type Ⅰ collagen(PICP) and carboxyterminal cross-linked telopeptide of type Ⅰ collagen (ICTP), which represent the rates of synthesis and degradation of type Ⅰ collagen, were determined by radioimmunoassay in 56 patients with multiple myeloma (MM) and 22 healthy controls. It was discovered that serum concentrations of both PICP and ICTP were higher in MM than those in healthy controls (P<0. 01 ). With the disease progressing and the number of bone lesions increasing,serum concentration of ICTP elevated while serum concentration of PICP showed no significant change. Neither serum PICP nor ICTP concentration was related to M-component classes. Our results indicated that serum ICTP concentration was a good serological marker to reflect severity of bone lesions in MM and elevated serum PICP concentration might be due to compensatory increase in type Ⅰ collagen synthesis. Moreover, we also found that serum ICTP concentrations in MM correlated with serum interleukin-6 (IL-6) activities (r= 0. 610, P< 0. 01),which confirms the effectiveness of IL-6 as an osteoclast activating factor.展开更多
Detailed investigations on the filamentary structures associated with the type-I edge-localized modes（ELMs） should be helpful for protecting the materials of a plasma-facing wall on a future large device.Related exp...Detailed investigations on the filamentary structures associated with the type-I edge-localized modes（ELMs） should be helpful for protecting the materials of a plasma-facing wall on a future large device.Related experiments have been carefully conducted in the Experimental Advanced Superconducting Tokamak（EAST） using combined Langmuir-magnetic probes.The experimental results indicate that the radially outward velocity of type-I ELMy filaments can be up to 1.7 kms^（-1） in the far scrape-off layer（SOL） region.It is remarkable that the electron temperature of these filaments is detected to be ~50eV,corresponding to a fraction of 1/6 to the temperature near the pedestal top,while the density ~3×10^（19）m^（-3） of these filaments could be approximate to the line-averaged density.In addition,associated magnetic fluctuations have been clearly observed at the same time,which show good agreement with the density perturbations.A localized current on the order of ~100kA could be estimated within the filaments.展开更多
The Democratic Republic of the Congo holds important reserves of oil shale which is still under geological status.Herein,the characterization and pyrolysis kinetics of typeⅠkerogen-rich oil shale of the western Centr...The Democratic Republic of the Congo holds important reserves of oil shale which is still under geological status.Herein,the characterization and pyrolysis kinetics of typeⅠkerogen-rich oil shale of the western Central Kongo(CK)were investigated.X-ray diffraction,Fourier-transform infrared spectroscopy and thermal analysis(TG/DTA)showed that CK oil shale exhibits a siliceous mineral matrix with a consistent organic matter rich in aliphatic chains.The pyrolysis behavior of kerogen revealed the presence of a single mass loss between 300 and 550°C,estimated at 12.5%and attributed to the oil production stage.Non-isothermal kinetics was performed by determining the activation energy using the iterative isoconversional model-free methods and exhibits a constant value with E=211.5±4.7 kJ mol.1.The most probable kinetic model describing the kerogen pyrolysis mechanism was obtained using the Coats–Redfern and Arrhenius plot methods.The results showed a unique kinetic triplet confirming the nature of kerogen,predominantly typeⅠand reinforcing the previously reported geochemical characteristics of the CK oil shale.Besides,the calculation of thermodynamic parameters(ΔH~*,ΔS~*andΔG~*)corresponding to the pyrolysis of typeⅠkerogen revealed that the process is non-spontaneous,in agreement with DTA experiments.展开更多
BACKGROUND Neurofibromatosis type Ⅰ(NF1) is the most frequent subtype of neurofibromatosis. Its related tumor-suppressor syndromes are characterized by a predisposition to multiple tumor types and other disorder pres...BACKGROUND Neurofibromatosis type Ⅰ(NF1) is the most frequent subtype of neurofibromatosis. Its related tumor-suppressor syndromes are characterized by a predisposition to multiple tumor types and other disorder presentations. In addition, the incidence of tumors is much higher in patients with neurofibromatosis type Ⅰ. However, there are very few reports at home and abroad on this topic. Here, we present a case of NF1 with spindle cell sarcoma.CASE SUMMARY A 50-year-old male was found to have a right axillary mass for 20 years.Specialist examination found cafe-au-lait spots on many parts of the skin,rounded nodules in the skin, a bulge in the right armpit, touching a lump(10 cm× 6 cm, hard, unclear boundary, poor mobility, local tenderness). The anterior side of the thigh felt weakened on the opposite side;in the right groin a swollen lymph node(hard, clear border, good mobility, local tenderness). According to the results of positron emission tomography/computed tomography, puncture pathology and immunohistochemistry, genetic testing, a diagnosis of NF1 with spindle cell sarcoma was confirmed. According to the genetic testing result, the patient was given a targeted treatment with crizotinib.CONCLUSION Surgery, chemotherapy and radiotherapy are the main treatment methods of NF1. However, with the continuous progress of molecular biology research,molecular targeted therapy may bring benefits for patients.展开更多
BRAF has been recognized as a promising target for cancer therapy. A number of crystal structures have been published. Molecular docking is one of the most effective techniques in the field of computer-aided drug des...BRAF has been recognized as a promising target for cancer therapy. A number of crystal structures have been published. Molecular docking is one of the most effective techniques in the field of computer-aided drug design（CADD）. Appropriate protein conformation and docking method are essential for the successful virtual screening experiments. One approach considering protein flexibility and multiple docking methods was proposed in this study. Six DFG-in/αC-helix-out crystal structures of BRAF, three docking programs（Glide, GOLD and Ligand Fit） and 12 scoring functions were applied for the best combination by judging from the results of pose prediction and retrospective virtual screening（VS）. The most accurate results（mean RMSD of about 0.6 A） of pose prediction were obtained with two complex structures（PDB： 3 C4 C and 3 SKC） using Glide SP. From the retrospective VS, the most active compounds were identified by using the complex structure of 3 SKC, indicated by a ROC/AUC score of 0.998 and an EF of 20.6 at 5% of the database screen with Glide-SP. On the whole, PDB 3 SKC could achieve a higher rate of correct reproduction, a better enrichment and more diverse compounds. A comparison of 3 SKC and the other X-ray crystal structures led to a rationale for the docking results. PDB 3 SKC could achieve a broad range of sulfonamide substitutions through an expanded hydrophobic pocket formed by a further shift of the αC-helix. Our study emphasized the necessity and significance of protein flexibility and scoring functions in both ligand docking and virtual screening.展开更多
基金Project supported by the National Basic Research Program of China (Grant Nos 2007CB607501 and 2007CB607503)Yunnan Natural Science Fund (Grant No 2008CD114)
文摘N-type Si-based type-Ⅰ clathrates with different Ga content were synthesized by combining the solid-state reaction method,melting method and spark plasma sintering （SPS） method.The effects of Ga composition on high temperature thermoelectric transport properties were investigated.The results show that at room temperature,the carrier concentration decreases, while the carrier mobility increases slightly with increasing Ga content.The Seebeck coefficient increases with increasing Ga content. Among all the samples,Ba7.93Ga17.13Si28.72exhibits higher Seebeck coefficient than the others and reaches -135μV·K^-1 at 1000 K.The sample prepared by this method exhibits very high electrical conductivity,and reaches 1.95x 10^5 S·m^-1 for Ba8.01Ga16.61Si28.93 at room temperature.The thermal conductivity of all samples is almost temperature independent in the temperature range of 300-1000 K,indicating the behaviour of a typical metal.The maximum ZT value of 0.75 is obtained at 1000 K for the compound Ba7.93Ga17.13Si28.72.
基金Supported by China National Science and Technology Major Project(2017ZX05009-005-003).
文摘The relationship between NaCl concentration and the phase change behavior of microemulsion of anionic surfactant was characterized by the salinity scan experiments.The wettability of WinsorⅠtype surfactant solution(WⅠsolution)and the effect of NaCL concentration on phase change behavior of WⅠsolution and imbibition in oil-wet porous media were investigated by microfluidic experiments in this study.The WⅠsolution and WinsorⅠtype microemulsion are similar in wetting phase with stronger wettability than other phases.Two main mechanisms of WⅠsolution enhancing imbibitions recovery in oil wet porous media are the wetting phase drive and residual oil solubilization.Under the salinity condition of WinsorⅠtype microemulsion,the NaCl concentration has strong impact on the imbibition mechanism of WⅠsolution,the higher the NaCl concentration,the complex the imbibition process and the higher the imbibition efficiency will be.The NaCl concentration has strong impact on the solubilization ability to oil of the WⅠsolution,the higher the NaCl concentration,the stronger the solubility of the WⅠsolution to residual oil will be.
文摘AIM To evaluate the incidence of lymph node metastasis （LNM） and its risk factors in patients with Siewert type Ⅰ and type Ⅱ pT1 adenocarcinomas.METHODS We enrolled 85 patients [69 men, 16 women; median age （range）, 67 （38-84） years] who had undergone esophagectomy or proximal gastrectomy for Siewert type Ⅰ and type Ⅱ pT1 adenocarcinomas. Predictive risk factors of LNM included age, sex, location of the tumor center, confirmed Barrett’s esophageal adenocarcinoma, tumor size, macroscopic tumor type, pathology, invasion depth, presence of ulceration, and lymphovascular invasion. Multivariate logistic regression analysis was used to identify factors predicting LNM. We also evaluated the frequencies of LNM for Siewert type Ⅰ and type Ⅱ pT1 adenocarcinomas in meta-data analysis.RESULTSLNMs were found in 11 out of 85 patients （12.9%, 95%CI： 5.8-20.0）. Only 1 of the 15 patients （6.6%, 95%CI： 0.0-19.2） who had a final diagnosis of pT1a adenocarcinoma had a positive LNM, whereas 10 of the 70 patients （14.2%, 95%CI： 6.0-22.4） with a final diagnosis of pT1b adenocarcinoma had positive LNM. Furthermore, only one of the 30 patients （3.3%, 95%CI： 0.0-9.7） with a tumor invasion depth within 500 μm from muscularis mucosae had positive LNM. Poor differentiation and lymphovascular invasion were independently associated with a risk of LNM. In meta-data analysis, 12 of the 355 patients （3.3%, 95%CI： 1.5-5.2） who had a final diagnosis of pT1a adenocarcinoma had a positive LNM, whereas 91 of the 438 patients （20.7%, 95%CI： 16.9-24.5） with a fnal diagnosis of pT1b adenocarcinoma had positive LNM.CONCLUSIONWe consider endoscopic submucosal dissection （ESD） is suitable for patients with Siewert type Ⅰ and type Ⅱ T1a adenocarcinomas. For patients with T1b adenocarcinoma, especially invasion depth is within 500 μm from muscularis mucosae with no other risk factor for LNM, diagnostic ESD could be a treatment option according to the overall status of patients and the presence of comorbidities.
文摘In this study, serum concentrations of carboxyterminal propeptide of type Ⅰ collagen(PICP) and carboxyterminal cross-linked telopeptide of type Ⅰ collagen (ICTP), which represent the rates of synthesis and degradation of type Ⅰ collagen, were determined by radioimmunoassay in 56 patients with multiple myeloma (MM) and 22 healthy controls. It was discovered that serum concentrations of both PICP and ICTP were higher in MM than those in healthy controls (P<0. 01 ). With the disease progressing and the number of bone lesions increasing,serum concentration of ICTP elevated while serum concentration of PICP showed no significant change. Neither serum PICP nor ICTP concentration was related to M-component classes. Our results indicated that serum ICTP concentration was a good serological marker to reflect severity of bone lesions in MM and elevated serum PICP concentration might be due to compensatory increase in type Ⅰ collagen synthesis. Moreover, we also found that serum ICTP concentrations in MM correlated with serum interleukin-6 (IL-6) activities (r= 0. 610, P< 0. 01),which confirms the effectiveness of IL-6 as an osteoclast activating factor.
基金supported by National Natural Science Foundation of China under Contracts Nos.11275047,11705128,11422546,11575235,11575236 and 11505222Key Research Program of Frontier Sciences,CAS,Grant No.QYZDB-SSWSLH001National Magnetic Confinement Fusion Science Program of China under Contract Nos.2015GB101000 and 2013GB107003
文摘Detailed investigations on the filamentary structures associated with the type-I edge-localized modes（ELMs） should be helpful for protecting the materials of a plasma-facing wall on a future large device.Related experiments have been carefully conducted in the Experimental Advanced Superconducting Tokamak（EAST） using combined Langmuir-magnetic probes.The experimental results indicate that the radially outward velocity of type-I ELMy filaments can be up to 1.7 kms^（-1） in the far scrape-off layer（SOL） region.It is remarkable that the electron temperature of these filaments is detected to be ~50eV,corresponding to a fraction of 1/6 to the temperature near the pedestal top,while the density ~3×10^（19）m^（-3） of these filaments could be approximate to the line-averaged density.In addition,associated magnetic fluctuations have been clearly observed at the same time,which show good agreement with the density perturbations.A localized current on the order of ~100kA could be estimated within the filaments.
基金financially supported by University of Mohammed V-Morocco under the Project No.SCH 04/09 and HassanⅡAcademy of Science and Technology,Morocco.
文摘The Democratic Republic of the Congo holds important reserves of oil shale which is still under geological status.Herein,the characterization and pyrolysis kinetics of typeⅠkerogen-rich oil shale of the western Central Kongo(CK)were investigated.X-ray diffraction,Fourier-transform infrared spectroscopy and thermal analysis(TG/DTA)showed that CK oil shale exhibits a siliceous mineral matrix with a consistent organic matter rich in aliphatic chains.The pyrolysis behavior of kerogen revealed the presence of a single mass loss between 300 and 550°C,estimated at 12.5%and attributed to the oil production stage.Non-isothermal kinetics was performed by determining the activation energy using the iterative isoconversional model-free methods and exhibits a constant value with E=211.5±4.7 kJ mol.1.The most probable kinetic model describing the kerogen pyrolysis mechanism was obtained using the Coats–Redfern and Arrhenius plot methods.The results showed a unique kinetic triplet confirming the nature of kerogen,predominantly typeⅠand reinforcing the previously reported geochemical characteristics of the CK oil shale.Besides,the calculation of thermodynamic parameters(ΔH~*,ΔS~*andΔG~*)corresponding to the pyrolysis of typeⅠkerogen revealed that the process is non-spontaneous,in agreement with DTA experiments.
文摘BACKGROUND Neurofibromatosis type Ⅰ(NF1) is the most frequent subtype of neurofibromatosis. Its related tumor-suppressor syndromes are characterized by a predisposition to multiple tumor types and other disorder presentations. In addition, the incidence of tumors is much higher in patients with neurofibromatosis type Ⅰ. However, there are very few reports at home and abroad on this topic. Here, we present a case of NF1 with spindle cell sarcoma.CASE SUMMARY A 50-year-old male was found to have a right axillary mass for 20 years.Specialist examination found cafe-au-lait spots on many parts of the skin,rounded nodules in the skin, a bulge in the right armpit, touching a lump(10 cm× 6 cm, hard, unclear boundary, poor mobility, local tenderness). The anterior side of the thigh felt weakened on the opposite side;in the right groin a swollen lymph node(hard, clear border, good mobility, local tenderness). According to the results of positron emission tomography/computed tomography, puncture pathology and immunohistochemistry, genetic testing, a diagnosis of NF1 with spindle cell sarcoma was confirmed. According to the genetic testing result, the patient was given a targeted treatment with crizotinib.CONCLUSION Surgery, chemotherapy and radiotherapy are the main treatment methods of NF1. However, with the continuous progress of molecular biology research,molecular targeted therapy may bring benefits for patients.
基金supported by the National Natural Science Foundation of China(21102181,81302634 and 21572273)
文摘BRAF has been recognized as a promising target for cancer therapy. A number of crystal structures have been published. Molecular docking is one of the most effective techniques in the field of computer-aided drug design（CADD）. Appropriate protein conformation and docking method are essential for the successful virtual screening experiments. One approach considering protein flexibility and multiple docking methods was proposed in this study. Six DFG-in/αC-helix-out crystal structures of BRAF, three docking programs（Glide, GOLD and Ligand Fit） and 12 scoring functions were applied for the best combination by judging from the results of pose prediction and retrospective virtual screening（VS）. The most accurate results（mean RMSD of about 0.6 A） of pose prediction were obtained with two complex structures（PDB： 3 C4 C and 3 SKC） using Glide SP. From the retrospective VS, the most active compounds were identified by using the complex structure of 3 SKC, indicated by a ROC/AUC score of 0.998 and an EF of 20.6 at 5% of the database screen with Glide-SP. On the whole, PDB 3 SKC could achieve a higher rate of correct reproduction, a better enrichment and more diverse compounds. A comparison of 3 SKC and the other X-ray crystal structures led to a rationale for the docking results. PDB 3 SKC could achieve a broad range of sulfonamide substitutions through an expanded hydrophobic pocket formed by a further shift of the αC-helix. Our study emphasized the necessity and significance of protein flexibility and scoring functions in both ligand docking and virtual screening.
