Large-scale granitic plutons are exposed in the Ergun block in the northern part of the Da Hinggan Range, but their emplacement age and petrogenesis remain un-known. Of these plutons, the Tahe pluton is composed mainl...Large-scale granitic plutons are exposed in the Ergun block in the northern part of the Da Hinggan Range, but their emplacement age and petrogenesis remain un-known. Of these plutons, the Tahe pluton is composed mainly of porphyritic syenogranite and monzogranite, with minor hornblende alkali feldspar granite and gabbro, which have affinities to post-orogenic granitoids. Laser-ablation Induc-tively Coupled Plasma Mass-spectroscope (LA-ICP-MS) analysis shows that the major rock types of the Tahe pluton formed at 494-480 Ma ago, indicating its emplacement in the Early Paleozoic. It is concluded, therefore, that the colli-sion between the Ergun and the Xing’an blocks ended in Early Paleozoic. Considering the geochronological data of the plutons in the adjacent areas, the Early Paleozoic evolu-tionary history of the Ergun block is similar to the central Mongolia and the Tuvino blocks in Mongolia, and the Ergun block should be a part of the accretionary continental mar-gin in the southern Siberian Craton.展开更多
Salvia miltiorrhiza Bunge(SM) is a very popular medicinal plant that has been extensively applied for many years to treat various diseases, especially coronary heart diseases and cerebrovascular diseases, either alone...Salvia miltiorrhiza Bunge(SM) is a very popular medicinal plant that has been extensively applied for many years to treat various diseases, especially coronary heart diseases and cerebrovascular diseases, either alone or in combination with other Chinese plant-based medicines. Although a large number of studies on SM have been performed, they are scattered across a variety of publications. The present review is an up-to-date summary of the published scientific information about the traditional uses, chemical constituents, pharmacological effects, side effects, and drug interactions with SM, in order to lay the foundation for further investigations and better utilization of SM. SM contains diverse chemical components including diterpenoid quinones, hydrophilic phenolic acids, and essential oils. Many pharmacological studies have been done on SM during the last 30 years, focusing on the cardiovascular and cerebrovascular effects, and the antioxidative, neuroprotective, antifibrotic, anti-inflammatory, and antineoplastic activities. The research results strongly support the notion that SM has beneficial therapeutic properties and has a potential of being an effective adaptogenic remedy.展开更多
Transforming growth factor-beta（TGF-β）/bone morphogenetic protein（BMP） plays a fundamental role in the regulation of bone organogenesis through the activation of receptor serine/threonine kinases. Perturbations o...Transforming growth factor-beta（TGF-β）/bone morphogenetic protein（BMP） plays a fundamental role in the regulation of bone organogenesis through the activation of receptor serine/threonine kinases. Perturbations of TGF-β/BMP activity are almost invariably linked to a wide variety of clinical outcomes, i.e., skeletal, extra skeletal anomalies, autoimmune, cancer, and cardiovascular diseases. Phosphorylation of TGF-β（I/II） or BMP receptors activates intracellular downstream Smads, the transducer of TGF-β/BMP signals. This signaling is modulated by various factors and pathways, including transcription factor Runx2. The signaling network in skeletal development and bone formation is overwhelmingly complex and highly time and space specific.Additive, positive, negative, or synergistic effects are observed when TGF-β/BMP interacts with the pathways of MAPK, Wnt, Hedgehog（Hh）, Notch, Akt/m TOR, and mi RNA to regulate the effects of BMP-induced signaling in bone dynamics. Accumulating evidence indicates that Runx2 is the key integrator, whereas Hh is a possible modulator, mi RNAs are regulators, and b-catenin is a mediator/regulator within the extensive intracellular network. This review focuses on the activation of BMP signaling and interaction with other regulatory components and pathways highlighting the molecular mechanisms regarding TGF-β/BMP function and regulation that could allow understanding the complexity of bone tissue dynamics.展开更多
Gastric cancer(GC)is the fourth most common cancer in the world with more than 70%of cases occur in the developing world.More than 50%of cases occur in Eastern Asia.GC is the second leading cause of cancer death in bo...Gastric cancer(GC)is the fourth most common cancer in the world with more than 70%of cases occur in the developing world.More than 50%of cases occur in Eastern Asia.GC is the second leading cause of cancer death in both sexes worldwide.In Asia,GC is the third most common cancer after breast and lung and is the second most common cause of cancer death after lung cancer.Although the incidence and mortality rates are slowly declining in many countries of Asia,GC still remains a significant public health problem.The incidence and mortality varies according to the geographic area in Asia.These variations are closely related to the prevalence of GC risk factors;especially Helicobacter pylori(H.pylori)and its molecular virulent characteristics.The gradual and consistent improvements in socioeconomic conditions in Asia have lowered the H.pylori seroprevalence rates leading to a reduction in the GC incidence.However,GC remains a significant public health and an economic burden in Asia.There has been no recent systemic review of GC incidence,mortality,and H.pylori molecular epidemiology in Asia.The aim of this report is to review the GC incidence,mortality,and linkage to H.pylori in Asia.展开更多
AIM： To analyze the relevance of the microRNA miR-196a for colorectal oncogenesis.METHODS： The impact of miR-196a on the restriction targets HoxA7, HoxBS, HoxC8 and HoxD8 was analyzed by reverse transcription polyme...AIM： To analyze the relevance of the microRNA miR-196a for colorectal oncogenesis.METHODS： The impact of miR-196a on the restriction targets HoxA7, HoxBS, HoxC8 and HoxD8 was analyzed by reverse transcription polymerase chain reaction（RT-PCR） after transient transfection of SW480 cancer cells. The miR-196a transcription profile in colorectalcancer samples, mucosa samples and diverse cancercell lines was quantified by RT-PCR. Transiently miR-196a-transfected colorectal cancer cells were used for diverse functional assays in vitro and for a xenograft lung metastasis model in vivo.RESULTS： HoxA7, HoxB8, HoxC8 and HoxD8 wererestricted by miR-196a in a dose-dependent andgene-specific manner. High levels of miR-196aactivated the AKT signaling pathway as indicated byincreased phosphorylation of AKT. In addition, highlevels of miR-196a promoted cancer cell detachment,migration, invasion and chemosensitivity towardsplatin derivatives but did not impact on proliferationor apoptosis. Furthermore, miR-196a increased thedevelopment of lung metastases in mice after tail veininjection.展开更多
As is well known to mineral processing scientists and engineers, fine and ultrafine particles are difficult to float mainly due to the low bubble-particle collision efficiencies. Though many efforts have been made to ...As is well known to mineral processing scientists and engineers, fine and ultrafine particles are difficult to float mainly due to the low bubble-particle collision efficiencies. Though many efforts have been made to improve flotation performance of fine and ultrafine particles, there is still much more to be done. In this paper, the effects of nano-microbubbles （nanobuhbles and microbubbles） on the flotation of fine （-38 ＋ 14.36 μm） and ultrafine （-14.36 ＋ 5μm） chalcopyrite particles were investigated in a laboratory scale Denver flotation cell. Nano-microbubbles were generated using a specially-designed nano- microbubble generator based on the cavitation phenomenon in Venturi tubes. In order to better under- stand the mechanisms of nano-microbubble enhanced froth flotation of fine and ultrafine chalcopyrite particles, the nano-microbubble size distribution, stability and the effect of frother concentration on nano- bubble size were also studied by a laser diffraction method. Comparative flotation tests were performed in the presence and absence of nano-microbubbles to evaluate their impact on the fine and ultrafine chalcopyrite particle flotation recovery. According to the results, the mean size of nano-microbubbles increased over time, and decreased with increase of frother concentration. The laboratory-scale flotation test results indicated that flotation recovery of chalcopyrite fine and ultrafine particles increased by approximately 16-21% in the presence of nano-microbubbles, depending on operating conditions of the process. The presence of nano-microbubbles increased the recovery of ultrafine particles （-14.36 ＋ 5 μm） more than that of fine particles （-38 ＋ 14.36 μm）. Another major advantage is that the use of nano-microbubbles reduced the collector and frother consumptions by up to 75% and 50%, respectively.展开更多
BACKGROUND:Hepatitis B virus(HBV)infection is a major cause of mortality and morbidity globally.The quest continues to identify viral factors that influence disease progression and severity as well as responses to tre...BACKGROUND:Hepatitis B virus(HBV)infection is a major cause of mortality and morbidity globally.The quest continues to identify viral factors that influence disease progression and severity as well as responses to treatment of HBV infection.Based on variations in HBV,the virus has been divided into a number of genotypes. DATA SOURCES:Review of published literature on HBV genotypes. RESULTS:HBV genotypes are likely to be important in determining the severity and progression of HBV-induced liver disease as well as responses to different anti-viral agents. CONCLUSION:Although HBV genotyping is not yet recommended for routine use in treating HBV infection, available data suggest that,as in hepatitis C virus infection, HBV genotyping is also likely to become a routine investigation for HBV treatment,perhaps in the not too distant future.展开更多
A significant amount of aluminum dross is available as a waste in foundry industries in Bangladesh. In this study, alumina was ex- tracted from aluminum dross collected from two foundry industries situated in Dhamrai ...A significant amount of aluminum dross is available as a waste in foundry industries in Bangladesh. In this study, alumina was ex- tracted from aluminum dross collected from two foundry industries situated in Dhamrai and Manikgang, near the capital city, Dhaka. Alu- minum dross samples were found to approximately contain 75wt% A1203 and 12wt% SIO2. An acid dissolution process was used to recover the alumina value from the dross. The effects of various parameters, e.g., temperature, acid concentration, and leaching time, on the extrac- tion of alumina were studied to optimize the dissolution process. First, AI（OH）3 was produced in the form of a gel. Calcination of the AI（OH）3 gel at 1000℃, 1200℃, and 1400℃ for 2 h produced O-AlcOa, （t~＋O）-A1203, and u-alumina powder, respectively. Thermal charac- terization of the AI（OH）3 gel was performed by thermogravimetric/differential thermal analysis （TG/DTA） and differential scanning calo- rimetry （DSC）. The phases and crystallite size of the alumina were determined by X-ray diffraction analysis. The dimensions of the alumina were found to be on the nano level. The chemical compositions of the aluminum dross and alumina were determined by X-ray fluorescence （XRF） spectroscopy. The microstructure and morphology of the alumina were studied with scanning electron microscopy. The purity of the alumina extracted in this study was found to be 99.0%. Thus, it is expected that the obtained alumina powders can be potentially utilized as biomaterials.展开更多
Quartz, the second most abundant mineral in the earth's crust, is a gangue mineral in practically every flotation process. Coarse quartz flotation has been a long standing problem in various mineral processing pla...Quartz, the second most abundant mineral in the earth's crust, is a gangue mineral in practically every flotation process. Coarse quartz flotation has been a long standing problem in various mineral processing plants to reduce milling cost and increase valuable mineral recovery. Based on this, the effects of nanobubbles(NBs) and hydrodynamic parameters on coarse quartz particle flotation were systematically investigated. Mechanical flotation experiments were carried out using the 7 cm and 9 cm diameter impellers in order to produce different hydrodynamic conditions. 900–1300 rpm impeller speeds were used for the 7 cm diameter impeller and 554–786 rpm for the 9 cm diameter impeller. The results show that the presence of NBs increased the flotation recovery of à425 + 106 lm quartz by up to 21%. For the7 cm diameter impeller, the maximum flotation recoveries of 86.4% and 98% were obtained in the absence and presence of NBs at Reynolds number(Re) of 81,000 and 66,000, respectively. For the 9 cm diameter impeller, the maximum recoveries of 86.3% and 97.5% were obtained in the absence and presence of NBs at Re of 90,000 and 75,000, respectively. NBs increased the flotation rate constant up to 36%.展开更多
Membrane technology is becoming more important for CO,_ separation from natural gas in the new era due to its process simplicity, relative ease of operation and control, compact, and easy to scale up as compared with ...Membrane technology is becoming more important for CO,_ separation from natural gas in the new era due to its process simplicity, relative ease of operation and control, compact, and easy to scale up as compared with conventional processes. Conventional processes such as absorption and adsorption for CO2 separation from natural gas are generally more energy demanding and costly for both operation and maintenance. Polymeric membranes are the current commercial membranes used for CO2 separation from natural gas. However, polymeric membranes possess drawbacks such as low permeability and selectivity, plasticization at high temperatures, as well as insufficient thermal and chemical stability. The shortcomings of commercial polymeric membranes have motivated researchers to opt for other alternatives, especially inorganic membranes due to their higher thermal stability, good chemical resistance to solvents, high mechanical strength and long lifetime. Surface modifications can be utilized in inorganic membranes to further enhance the selectivity, permeability or catalytic activities of the membrane. This paper is to provide a comprehensive review on gas separation, comparing membrane technology with other conventional methods of recovering CO2 from natural gas, challenges of current commercial polymeric membranes and inorganic membranes for CO2 removal and membrane surface modification for improved selectivity.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.40372038 and 40325006)National Oil Gas Special Project(Grant No.XQ-2004-07).
文摘Large-scale granitic plutons are exposed in the Ergun block in the northern part of the Da Hinggan Range, but their emplacement age and petrogenesis remain un-known. Of these plutons, the Tahe pluton is composed mainly of porphyritic syenogranite and monzogranite, with minor hornblende alkali feldspar granite and gabbro, which have affinities to post-orogenic granitoids. Laser-ablation Induc-tively Coupled Plasma Mass-spectroscope (LA-ICP-MS) analysis shows that the major rock types of the Tahe pluton formed at 494-480 Ma ago, indicating its emplacement in the Early Paleozoic. It is concluded, therefore, that the colli-sion between the Ergun and the Xing’an blocks ended in Early Paleozoic. Considering the geochronological data of the plutons in the adjacent areas, the Early Paleozoic evolu-tionary history of the Ergun block is similar to the central Mongolia and the Tuvino blocks in Mongolia, and the Ergun block should be a part of the accretionary continental mar-gin in the southern Siberian Craton.
基金supported by the Young Scientist Special Project of the National High Technology Research and Development Program of China(No.2014AA020508)National Nature Science Foundation of China(No.81473301)
文摘Salvia miltiorrhiza Bunge(SM) is a very popular medicinal plant that has been extensively applied for many years to treat various diseases, especially coronary heart diseases and cerebrovascular diseases, either alone or in combination with other Chinese plant-based medicines. Although a large number of studies on SM have been performed, they are scattered across a variety of publications. The present review is an up-to-date summary of the published scientific information about the traditional uses, chemical constituents, pharmacological effects, side effects, and drug interactions with SM, in order to lay the foundation for further investigations and better utilization of SM. SM contains diverse chemical components including diterpenoid quinones, hydrophilic phenolic acids, and essential oils. Many pharmacological studies have been done on SM during the last 30 years, focusing on the cardiovascular and cerebrovascular effects, and the antioxidative, neuroprotective, antifibrotic, anti-inflammatory, and antineoplastic activities. The research results strongly support the notion that SM has beneficial therapeutic properties and has a potential of being an effective adaptogenic remedy.
文摘Transforming growth factor-beta（TGF-β）/bone morphogenetic protein（BMP） plays a fundamental role in the regulation of bone organogenesis through the activation of receptor serine/threonine kinases. Perturbations of TGF-β/BMP activity are almost invariably linked to a wide variety of clinical outcomes, i.e., skeletal, extra skeletal anomalies, autoimmune, cancer, and cardiovascular diseases. Phosphorylation of TGF-β（I/II） or BMP receptors activates intracellular downstream Smads, the transducer of TGF-β/BMP signals. This signaling is modulated by various factors and pathways, including transcription factor Runx2. The signaling network in skeletal development and bone formation is overwhelmingly complex and highly time and space specific.Additive, positive, negative, or synergistic effects are observed when TGF-β/BMP interacts with the pathways of MAPK, Wnt, Hedgehog（Hh）, Notch, Akt/m TOR, and mi RNA to regulate the effects of BMP-induced signaling in bone dynamics. Accumulating evidence indicates that Runx2 is the key integrator, whereas Hh is a possible modulator, mi RNAs are regulators, and b-catenin is a mediator/regulator within the extensive intracellular network. This review focuses on the activation of BMP signaling and interaction with other regulatory components and pathways highlighting the molecular mechanisms regarding TGF-β/BMP function and regulation that could allow understanding the complexity of bone tissue dynamics.
文摘Gastric cancer(GC)is the fourth most common cancer in the world with more than 70%of cases occur in the developing world.More than 50%of cases occur in Eastern Asia.GC is the second leading cause of cancer death in both sexes worldwide.In Asia,GC is the third most common cancer after breast and lung and is the second most common cause of cancer death after lung cancer.Although the incidence and mortality rates are slowly declining in many countries of Asia,GC still remains a significant public health problem.The incidence and mortality varies according to the geographic area in Asia.These variations are closely related to the prevalence of GC risk factors;especially Helicobacter pylori(H.pylori)and its molecular virulent characteristics.The gradual and consistent improvements in socioeconomic conditions in Asia have lowered the H.pylori seroprevalence rates leading to a reduction in the GC incidence.However,GC remains a significant public health and an economic burden in Asia.There has been no recent systemic review of GC incidence,mortality,and H.pylori molecular epidemiology in Asia.The aim of this report is to review the GC incidence,mortality,and linkage to H.pylori in Asia.
基金Supported by The University of Mainz Project Grant
文摘AIM： To analyze the relevance of the microRNA miR-196a for colorectal oncogenesis.METHODS： The impact of miR-196a on the restriction targets HoxA7, HoxBS, HoxC8 and HoxD8 was analyzed by reverse transcription polymerase chain reaction（RT-PCR） after transient transfection of SW480 cancer cells. The miR-196a transcription profile in colorectalcancer samples, mucosa samples and diverse cancercell lines was quantified by RT-PCR. Transiently miR-196a-transfected colorectal cancer cells were used for diverse functional assays in vitro and for a xenograft lung metastasis model in vivo.RESULTS： HoxA7, HoxB8, HoxC8 and HoxD8 wererestricted by miR-196a in a dose-dependent andgene-specific manner. High levels of miR-196aactivated the AKT signaling pathway as indicated byincreased phosphorylation of AKT. In addition, highlevels of miR-196a promoted cancer cell detachment,migration, invasion and chemosensitivity towardsplatin derivatives but did not impact on proliferationor apoptosis. Furthermore, miR-196a increased thedevelopment of lung metastases in mice after tail veininjection.
基金the Tarbiat Modares University (TMU), the Iran Mineral Processing Research Center (IMPRC) and the IMIDRO for the technical assistance and financial support
文摘As is well known to mineral processing scientists and engineers, fine and ultrafine particles are difficult to float mainly due to the low bubble-particle collision efficiencies. Though many efforts have been made to improve flotation performance of fine and ultrafine particles, there is still much more to be done. In this paper, the effects of nano-microbubbles （nanobuhbles and microbubbles） on the flotation of fine （-38 ＋ 14.36 μm） and ultrafine （-14.36 ＋ 5μm） chalcopyrite particles were investigated in a laboratory scale Denver flotation cell. Nano-microbubbles were generated using a specially-designed nano- microbubble generator based on the cavitation phenomenon in Venturi tubes. In order to better under- stand the mechanisms of nano-microbubble enhanced froth flotation of fine and ultrafine chalcopyrite particles, the nano-microbubble size distribution, stability and the effect of frother concentration on nano- bubble size were also studied by a laser diffraction method. Comparative flotation tests were performed in the presence and absence of nano-microbubbles to evaluate their impact on the fine and ultrafine chalcopyrite particle flotation recovery. According to the results, the mean size of nano-microbubbles increased over time, and decreased with increase of frother concentration. The laboratory-scale flotation test results indicated that flotation recovery of chalcopyrite fine and ultrafine particles increased by approximately 16-21% in the presence of nano-microbubbles, depending on operating conditions of the process. The presence of nano-microbubbles increased the recovery of ultrafine particles （-14.36 ＋ 5 μm） more than that of fine particles （-38 ＋ 14.36 μm）. Another major advantage is that the use of nano-microbubbles reduced the collector and frother consumptions by up to 75% and 50%, respectively.
文摘BACKGROUND:Hepatitis B virus(HBV)infection is a major cause of mortality and morbidity globally.The quest continues to identify viral factors that influence disease progression and severity as well as responses to treatment of HBV infection.Based on variations in HBV,the virus has been divided into a number of genotypes. DATA SOURCES:Review of published literature on HBV genotypes. RESULTS:HBV genotypes are likely to be important in determining the severity and progression of HBV-induced liver disease as well as responses to different anti-viral agents. CONCLUSION:Although HBV genotyping is not yet recommended for routine use in treating HBV infection, available data suggest that,as in hepatitis C virus infection, HBV genotyping is also likely to become a routine investigation for HBV treatment,perhaps in the not too distant future.
文摘A significant amount of aluminum dross is available as a waste in foundry industries in Bangladesh. In this study, alumina was ex- tracted from aluminum dross collected from two foundry industries situated in Dhamrai and Manikgang, near the capital city, Dhaka. Alu- minum dross samples were found to approximately contain 75wt% A1203 and 12wt% SIO2. An acid dissolution process was used to recover the alumina value from the dross. The effects of various parameters, e.g., temperature, acid concentration, and leaching time, on the extrac- tion of alumina were studied to optimize the dissolution process. First, AI（OH）3 was produced in the form of a gel. Calcination of the AI（OH）3 gel at 1000℃, 1200℃, and 1400℃ for 2 h produced O-AlcOa, （t~＋O）-A1203, and u-alumina powder, respectively. Thermal charac- terization of the AI（OH）3 gel was performed by thermogravimetric/differential thermal analysis （TG/DTA） and differential scanning calo- rimetry （DSC）. The phases and crystallite size of the alumina were determined by X-ray diffraction analysis. The dimensions of the alumina were found to be on the nano level. The chemical compositions of the aluminum dross and alumina were determined by X-ray fluorescence （XRF） spectroscopy. The microstructure and morphology of the alumina were studied with scanning electron microscopy. The purity of the alumina extracted in this study was found to be 99.0%. Thus, it is expected that the obtained alumina powders can be potentially utilized as biomaterials.
文摘Quartz, the second most abundant mineral in the earth's crust, is a gangue mineral in practically every flotation process. Coarse quartz flotation has been a long standing problem in various mineral processing plants to reduce milling cost and increase valuable mineral recovery. Based on this, the effects of nanobubbles(NBs) and hydrodynamic parameters on coarse quartz particle flotation were systematically investigated. Mechanical flotation experiments were carried out using the 7 cm and 9 cm diameter impellers in order to produce different hydrodynamic conditions. 900–1300 rpm impeller speeds were used for the 7 cm diameter impeller and 554–786 rpm for the 9 cm diameter impeller. The results show that the presence of NBs increased the flotation recovery of à425 + 106 lm quartz by up to 21%. For the7 cm diameter impeller, the maximum flotation recoveries of 86.4% and 98% were obtained in the absence and presence of NBs at Reynolds number(Re) of 81,000 and 66,000, respectively. For the 9 cm diameter impeller, the maximum recoveries of 86.3% and 97.5% were obtained in the absence and presence of NBs at Re of 90,000 and 75,000, respectively. NBs increased the flotation rate constant up to 36%.
基金supported by the Ministry of Higher Education Malaysia through Long Term Research Grant Scheme (A/C Number 2110226-113-00)
文摘Membrane technology is becoming more important for CO,_ separation from natural gas in the new era due to its process simplicity, relative ease of operation and control, compact, and easy to scale up as compared with conventional processes. Conventional processes such as absorption and adsorption for CO2 separation from natural gas are generally more energy demanding and costly for both operation and maintenance. Polymeric membranes are the current commercial membranes used for CO2 separation from natural gas. However, polymeric membranes possess drawbacks such as low permeability and selectivity, plasticization at high temperatures, as well as insufficient thermal and chemical stability. The shortcomings of commercial polymeric membranes have motivated researchers to opt for other alternatives, especially inorganic membranes due to their higher thermal stability, good chemical resistance to solvents, high mechanical strength and long lifetime. Surface modifications can be utilized in inorganic membranes to further enhance the selectivity, permeability or catalytic activities of the membrane. This paper is to provide a comprehensive review on gas separation, comparing membrane technology with other conventional methods of recovering CO2 from natural gas, challenges of current commercial polymeric membranes and inorganic membranes for CO2 removal and membrane surface modification for improved selectivity.
