采用粒子图像测速技术(PIV)研究了双层改进型INTER-MIG桨搅拌槽内的流场,考察了流体粘度?、桨叶转速、底桨尺寸对流场的影响.结果表明,?<962.5 m Pa·s时随粘度增大,局部涡流增多,对整体混合有利;?=962.5 m Pa·s时形成2个...采用粒子图像测速技术(PIV)研究了双层改进型INTER-MIG桨搅拌槽内的流场,考察了流体粘度?、桨叶转速、底桨尺寸对流场的影响.结果表明,?<962.5 m Pa·s时随粘度增大,局部涡流增多,对整体混合有利;?=962.5 m Pa·s时形成2个涡合能力差的涡流,对整体混合不利.Re=459~918时,桨叶转速增加对叶端处无因次化速度无影响,随流体远离桨叶,无因次化速度随桨叶转速增大而增大.底桨尺寸增大对无因次化径向速度影响较小,对底桨所在区域无因次化轴向速度影响较大,底桨尺寸满足桨槽直径比D/T=0.57时无因次化轴向速度最大,湍动能最大,搅拌功率随底桨尺寸增大而增大.展开更多
Introduction: To investigate the inter-observer and inter-modality variabilities of two imaging guided equipments—cone-beam computed tomography (CBCT) and ultrasound (US) in kidney stereotactic body radiotherapy. Met...Introduction: To investigate the inter-observer and inter-modality variabilities of two imaging guided equipments—cone-beam computed tomography (CBCT) and ultrasound (US) in kidney stereotactic body radiotherapy. Methods: A renal metastasis case implanted with three gold anchor fiducial markers was firstly scanned by US to acquire a 3-dimension US image and followed by 4-dimension CBCT in every fraction. Seven observers retrospectively registered the pre-treatment images with the corresponding reference images based on the gold markers. Registration uncertainty of the observers between two imaging modalities was evaluated. Results: The uncertainties over whole treatment course in CBCT were 0.88 mm, 1.94 mm and 0.86 mm in lateral, longitudinal and vertical directions respectively;while 0.8 mm, 0.97 mm and 1.36 mm were found in US. Conclusion: The greatest uncertainty was found in longitudinal direction in CBCT due to the fact that the respiration motion is the most rigorous in cranial-caudal direction. In US, since the probe was hold almost in upright position, the strong echo in vertical direction was attributed to the greatest uncertainty for such direction.展开更多
Throughout the past years, the important role of translators has always been overlooked. The invisibility was even taken as one of the standards of a good translator. However, great change happens, especially after th...Throughout the past years, the important role of translators has always been overlooked. The invisibility was even taken as one of the standards of a good translator. However, great change happens, especially after the"culture turn"in translation study and the role of the translators has been laid emphasis on. This kind of sharp change has led to two extreme thoughts on this issue: scholars choose either total invisibility or complete subjectivity. This paper puts forward an inter-subjective system, in which the subjectivity should be emphasized only with constraints. The other subjects in the inter-subjective system contribute to the restriction of the subjectivity of the translator during the translation process.By writing this paper, the author wishes to present a comprehensive and balanced way of understanding translators' subjectivity. Therefore, no matter analyzing the translation process or evaluating translation products, people will be more objective towards the role of translators.展开更多
A learner’s stages of L2 development are connected by his or her L1 and culture.It is,accordingly,of paramount importance to understand the second language learners’culture and learning process and better assist the...A learner’s stages of L2 development are connected by his or her L1 and culture.It is,accordingly,of paramount importance to understand the second language learners’culture and learning process and better assist them through this process in the way of teaching them English.Similarly,inter-language theory(IL)and contrastive rhetoric are affected by factors,such as learner’s L1,learning experiences,and culture.This paper talks about these two theory’s characteristics,constructs,and importance,so language instructors may better understand the L2 learning phenomena and think out better methods to help language learners improve their language skills.展开更多
A quinine-derived thiourea-catalyzed inter-/intramolecular Michael cycloaddition of chromoneoxindole/benzofuranone synthons with 3-substituted methylenebenzofuranones has been established,which constructed enantiomeri...A quinine-derived thiourea-catalyzed inter-/intramolecular Michael cycloaddition of chromoneoxindole/benzofuranone synthons with 3-substituted methylenebenzofuranones has been established,which constructed enantiomerically pure bispiro[benzofuran-oxindole/benzofuran-chromanone]s bearing five consecutive stereocenters including two spiro quaternary carton centers in good yields(up to 93%) with high diastereoselectivities(up to>20:1 dr) and good enantioselectivities(up to>99% ee).Moreover,this is the first example of bifunctional chromone-benzofuranone synthon directed organocatalytic tandem reaction,and also the first example of the bispiro[benzofuran-oxindole] and bispirobenzofuranone,potentially useful in medicinal chemistry.展开更多
The authors have developed an integral view of the inter-decadal variability of July-August （JA） tropospheric temperature across the entire subtropical Northern Hemisphere. Using reanalysis data and complementary ba...The authors have developed an integral view of the inter-decadal variability of July-August （JA） tropospheric temperature across the entire subtropical Northern Hemisphere. Using reanalysis data and complementary balloon-borne measurements, the authors identify one major mode of variability for the period 1958 2001 which exhibits a significant cooling center over East Asia and warming centers over the North Atlantic and North Pacific. The cooling （warming） signals barotropically penetrate through the troposphere, with the strongest anomalies at 200-300 hPa. The amplitude of the cooling over East Asia is stronger than that of the warming over the North Atlantic （North Pacific） by a factor of 2 （3）. This dominant mode exhibits a declining tendency for the entire period examined, particularly before 1980. After the mid-1980s, the tendency has leveled off. Variations of the harmonious change of JA upper tropospheric temperature represented by the principal component of Empirical Orthogonal Function analysis exhibit significant negative （positive） correlations with SST anomalies in the eastern tropical Pacific and the western tropical Indian Ocean （mid-latitude North Pacific）. Possible mechanisms are discussed.展开更多
Air mass is inter-hemispherically redistributed, leading to an interesting phenomenon known as the Inter-Hemispheric Oscillation （IHO）. In the present article, the seasonality of the interannual IHO has been examine...Air mass is inter-hemispherically redistributed, leading to an interesting phenomenon known as the Inter-Hemispheric Oscillation （IHO）. In the present article, the seasonality of the interannual IHO has been examined by employing monthly mean reanalyses from NCEP/NCAR, EAR40, and JRA25 for the period of 1958–2006. It is found that the IHO indices as calculated from different reanalyses are generally consistent with each other. A distinct seesaw structure in all four seasons between the northern and southern hemispheres is observed as the IHO signature in both the surface air pressure anomalies （SAPAs） and the leading EOF component of the anomalous zonal mean quantities. When the SAPAs are positive （negative） in the northern hemisphere, they are negative （positive） in the southern hemisphere. Large values of SAPAs are usually observed in mid- and high-latitude areas in all but the solstice seasons. In boreal summer and winter, relatively stronger perturbations of IHO-related SAPA are found in the Asian monsoon region, which shows a large difference from the status in boreal spring and fall. This suggests that seasonal mean monsoon activity is globally linked via air mass redistribution globally on interannual timescales, showing a very interesting linkage between monsoons and the IHO in the global domain. In all seasons, large values of SAPA always exist over the Antarctic and the surrounding regions, implying a close relation with Antarctic oscillations.展开更多
Objective:The inter-α-trypsin inhibitor heavy chain 4(ITIH4)protein is involved in the development of tumors.However,the relationship between ITIH4 and ovarian cancer(OC)has not been extensively examined.This study a...Objective:The inter-α-trypsin inhibitor heavy chain 4(ITIH4)protein is involved in the development of tumors.However,the relationship between ITIH4 and ovarian cancer(OC)has not been extensively examined.This study aimed to explore the effect of ITIH4 on OC and to identify its underlying mechanism.Methods:Expressions of ITIH4 in OC tissues and cells were determined using quantitative reverse transcription polymerase chain reaction(RT-qPCR)and western blots.The function of ITIH4 in the OC cell line HO8910 pm was tested via ITIH4 knockdown.The cell growth rate was measured using MTT and colony formation assays.Flow cytometry was performed to evaluate cell cycle progression.Cell migration and invasion abilities were observed using the transwell migration assay.Results:ITIH4 was downregulated in OC tissues and cells.ITIH4 knockdown promoted cell growth and cell cycle progression.Consistent with these results,inhibition of ITIH4 in OC cells significantly increased cell migration and invasion abilities.Cox regression analysis suggests that ITIH4 expression alone is not a good predictor of the prognosis of malignant ovarian tumors in patients.Conclusions:ITIH4 inhibits the progression of OC,suggesting that ITIH4 may be a useful biomarker for OC.This study may provide a potential novel target for the treatment of OC.展开更多
Seismic processing characterizing thickness and borders of thin inter-beds has gradually evolved fi＇om post-stack migration to pre-stack migration, and the latter considers both vertical and lateral resolutions. As t...Seismic processing characterizing thickness and borders of thin inter-beds has gradually evolved fi＇om post-stack migration to pre-stack migration, and the latter considers both vertical and lateral resolutions. As the key processing methods for improving vertical and lateral resolution, conventional deconvolution and pre-stack time migration （PSTM） are not simply dominated by the estimation and compression of the wavelet because of its instability. Therefbre, considering the variations of wavelet frequency belbre, during and alter PSTM can obtain good common reflection point （CRP） gathers and imaging profiles of thin inter-beds. Based on the frequency characteristics of the wavelet before, during and after PSTM, a joint high-resolution processing method for thin inter-beds is proposed in this paper, including inverse Q filtering for high-frequency compensation before PSTM, optimum weighting Kirchhoff PSTM for preserving high-frequencies during PSTM, and wavelet harmonizer deconvolution tier consistent processing and frequency-band broadening after PSTM. An application to real data characterized by mudstone beds in the Oriente Basin proved that the joint high-resolution processing method is effective for determining the thickness and borders of thin inter-beds and is favorable for subsequent reservoir prediction and seismic inversions.展开更多
As a new composite welding heat source introduced in recent years, the cross-coupling arc uses a non-consumable electrode arc(plasma arc) and a consumable electrode arc(inter-wire arc) in cross-coupling, in which the ...As a new composite welding heat source introduced in recent years, the cross-coupling arc uses a non-consumable electrode arc(plasma arc) and a consumable electrode arc(inter-wire arc) in cross-coupling, in which the plasma arc is the main arc and the inter-wire arc is the vice arc, to realize the separate control of the heat input to the workpiece,arc force, and droplet transfer. To reveal the electrical characteristics of the inter-wire arc under the action of the plasma arc, in this study, rotating probes are used to sweep across the plasma arc. When the probes rotate into the plasma arc, a circuit is formed, and the electrical characteristics of the inter-wire arc are indirectly analyzed according to the circuit: the probe centering current and input voltage are used as the physical quantities. The results show that at a certain wire feed rate, the inter-wire arc current increases with increasing input voltage. When the input voltage is low, the wire feed rate has no obvious e ect on the inter-wire arc current. At a higher input voltage, where the wire feed rate is high, the inter-wire arc current decreases. With the increase in the plasma arc current, the inter-wire arc current first increases quickly and then increases slowly, and simultaneously, the striking arc time becomes longer.With the increase in the interval between the nozzle and the workpiece, the inter-wire arc current increases, but when the arc length increases to a certain limit, the slope of the welding current clearly declines.展开更多
文摘采用粒子图像测速技术(PIV)研究了双层改进型INTER-MIG桨搅拌槽内的流场,考察了流体粘度?、桨叶转速、底桨尺寸对流场的影响.结果表明,?<962.5 m Pa·s时随粘度增大,局部涡流增多,对整体混合有利;?=962.5 m Pa·s时形成2个涡合能力差的涡流,对整体混合不利.Re=459~918时,桨叶转速增加对叶端处无因次化速度无影响,随流体远离桨叶,无因次化速度随桨叶转速增大而增大.底桨尺寸增大对无因次化径向速度影响较小,对底桨所在区域无因次化轴向速度影响较大,底桨尺寸满足桨槽直径比D/T=0.57时无因次化轴向速度最大,湍动能最大,搅拌功率随底桨尺寸增大而增大.
文摘Introduction: To investigate the inter-observer and inter-modality variabilities of two imaging guided equipments—cone-beam computed tomography (CBCT) and ultrasound (US) in kidney stereotactic body radiotherapy. Methods: A renal metastasis case implanted with three gold anchor fiducial markers was firstly scanned by US to acquire a 3-dimension US image and followed by 4-dimension CBCT in every fraction. Seven observers retrospectively registered the pre-treatment images with the corresponding reference images based on the gold markers. Registration uncertainty of the observers between two imaging modalities was evaluated. Results: The uncertainties over whole treatment course in CBCT were 0.88 mm, 1.94 mm and 0.86 mm in lateral, longitudinal and vertical directions respectively;while 0.8 mm, 0.97 mm and 1.36 mm were found in US. Conclusion: The greatest uncertainty was found in longitudinal direction in CBCT due to the fact that the respiration motion is the most rigorous in cranial-caudal direction. In US, since the probe was hold almost in upright position, the strong echo in vertical direction was attributed to the greatest uncertainty for such direction.
文摘Throughout the past years, the important role of translators has always been overlooked. The invisibility was even taken as one of the standards of a good translator. However, great change happens, especially after the"culture turn"in translation study and the role of the translators has been laid emphasis on. This kind of sharp change has led to two extreme thoughts on this issue: scholars choose either total invisibility or complete subjectivity. This paper puts forward an inter-subjective system, in which the subjectivity should be emphasized only with constraints. The other subjects in the inter-subjective system contribute to the restriction of the subjectivity of the translator during the translation process.By writing this paper, the author wishes to present a comprehensive and balanced way of understanding translators' subjectivity. Therefore, no matter analyzing the translation process or evaluating translation products, people will be more objective towards the role of translators.
文摘A learner’s stages of L2 development are connected by his or her L1 and culture.It is,accordingly,of paramount importance to understand the second language learners’culture and learning process and better assist them through this process in the way of teaching them English.Similarly,inter-language theory(IL)and contrastive rhetoric are affected by factors,such as learner’s L1,learning experiences,and culture.This paper talks about these two theory’s characteristics,constructs,and importance,so language instructors may better understand the L2 learning phenomena and think out better methods to help language learners improve their language skills.
基金financial support from the National Nature Science Foundation of China(Nos.81760625,81660576 and81560563)Projects of Guizhou Province(Nos.[2016]5623,JG[2016]06,[2019]1402,[2017]5609 and[2018]5781)。
文摘A quinine-derived thiourea-catalyzed inter-/intramolecular Michael cycloaddition of chromoneoxindole/benzofuranone synthons with 3-substituted methylenebenzofuranones has been established,which constructed enantiomerically pure bispiro[benzofuran-oxindole/benzofuran-chromanone]s bearing five consecutive stereocenters including two spiro quaternary carton centers in good yields(up to 93%) with high diastereoselectivities(up to>20:1 dr) and good enantioselectivities(up to>99% ee).Moreover,this is the first example of bifunctional chromone-benzofuranone synthon directed organocatalytic tandem reaction,and also the first example of the bispiro[benzofuran-oxindole] and bispirobenzofuranone,potentially useful in medicinal chemistry.
基金supported by the China Meteorological Administration(GYHY200706010,GYHY200806010)the Major State Basic Research Development Program of China under Grant Nos2006CB403603 and 2005CB321703the National Natural Science Foundation of China under Grant Nos40523001,40625014,and 90711004
文摘The authors have developed an integral view of the inter-decadal variability of July-August （JA） tropospheric temperature across the entire subtropical Northern Hemisphere. Using reanalysis data and complementary balloon-borne measurements, the authors identify one major mode of variability for the period 1958 2001 which exhibits a significant cooling center over East Asia and warming centers over the North Atlantic and North Pacific. The cooling （warming） signals barotropically penetrate through the troposphere, with the strongest anomalies at 200-300 hPa. The amplitude of the cooling over East Asia is stronger than that of the warming over the North Atlantic （North Pacific） by a factor of 2 （3）. This dominant mode exhibits a declining tendency for the entire period examined, particularly before 1980. After the mid-1980s, the tendency has leveled off. Variations of the harmonious change of JA upper tropospheric temperature represented by the principal component of Empirical Orthogonal Function analysis exhibit significant negative （positive） correlations with SST anomalies in the eastern tropical Pacific and the western tropical Indian Ocean （mid-latitude North Pacific）. Possible mechanisms are discussed.
基金supported jointlyby the National Key Technology R&D Program (GrantNo. 2007BAC29B02)the National Natural Science Foundation of China (NSFC, Grant No. 40675025)the Key Laboratory of Meteorological Disasters, Nanjing University of Information Science & Technology (NUIST,KLME060101)
文摘Air mass is inter-hemispherically redistributed, leading to an interesting phenomenon known as the Inter-Hemispheric Oscillation （IHO）. In the present article, the seasonality of the interannual IHO has been examined by employing monthly mean reanalyses from NCEP/NCAR, EAR40, and JRA25 for the period of 1958–2006. It is found that the IHO indices as calculated from different reanalyses are generally consistent with each other. A distinct seesaw structure in all four seasons between the northern and southern hemispheres is observed as the IHO signature in both the surface air pressure anomalies （SAPAs） and the leading EOF component of the anomalous zonal mean quantities. When the SAPAs are positive （negative） in the northern hemisphere, they are negative （positive） in the southern hemisphere. Large values of SAPAs are usually observed in mid- and high-latitude areas in all but the solstice seasons. In boreal summer and winter, relatively stronger perturbations of IHO-related SAPA are found in the Asian monsoon region, which shows a large difference from the status in boreal spring and fall. This suggests that seasonal mean monsoon activity is globally linked via air mass redistribution globally on interannual timescales, showing a very interesting linkage between monsoons and the IHO in the global domain. In all seasons, large values of SAPA always exist over the Antarctic and the surrounding regions, implying a close relation with Antarctic oscillations.
基金supported by Guangxi Scientific Research and Technology Development Project (No. 14124004-1-24)
文摘Objective:The inter-α-trypsin inhibitor heavy chain 4(ITIH4)protein is involved in the development of tumors.However,the relationship between ITIH4 and ovarian cancer(OC)has not been extensively examined.This study aimed to explore the effect of ITIH4 on OC and to identify its underlying mechanism.Methods:Expressions of ITIH4 in OC tissues and cells were determined using quantitative reverse transcription polymerase chain reaction(RT-qPCR)and western blots.The function of ITIH4 in the OC cell line HO8910 pm was tested via ITIH4 knockdown.The cell growth rate was measured using MTT and colony formation assays.Flow cytometry was performed to evaluate cell cycle progression.Cell migration and invasion abilities were observed using the transwell migration assay.Results:ITIH4 was downregulated in OC tissues and cells.ITIH4 knockdown promoted cell growth and cell cycle progression.Consistent with these results,inhibition of ITIH4 in OC cells significantly increased cell migration and invasion abilities.Cox regression analysis suggests that ITIH4 expression alone is not a good predictor of the prognosis of malignant ovarian tumors in patients.Conclusions:ITIH4 inhibits the progression of OC,suggesting that ITIH4 may be a useful biomarker for OC.This study may provide a potential novel target for the treatment of OC.
文摘Seismic processing characterizing thickness and borders of thin inter-beds has gradually evolved fi＇om post-stack migration to pre-stack migration, and the latter considers both vertical and lateral resolutions. As the key processing methods for improving vertical and lateral resolution, conventional deconvolution and pre-stack time migration （PSTM） are not simply dominated by the estimation and compression of the wavelet because of its instability. Therefbre, considering the variations of wavelet frequency belbre, during and alter PSTM can obtain good common reflection point （CRP） gathers and imaging profiles of thin inter-beds. Based on the frequency characteristics of the wavelet before, during and after PSTM, a joint high-resolution processing method for thin inter-beds is proposed in this paper, including inverse Q filtering for high-frequency compensation before PSTM, optimum weighting Kirchhoff PSTM for preserving high-frequencies during PSTM, and wavelet harmonizer deconvolution tier consistent processing and frequency-band broadening after PSTM. An application to real data characterized by mudstone beds in the Oriente Basin proved that the joint high-resolution processing method is effective for determining the thickness and borders of thin inter-beds and is favorable for subsequent reservoir prediction and seismic inversions.
基金Supported by National Natural Science Foundation of China(Grant No.51875004)Beijing Municipal Natural Science Foundation of China(Grant No.3172004)State Key Lab of Advanced Welding and Joining,Harbin Institute of Technology(Grant No.AWJ-16-M06)
文摘As a new composite welding heat source introduced in recent years, the cross-coupling arc uses a non-consumable electrode arc(plasma arc) and a consumable electrode arc(inter-wire arc) in cross-coupling, in which the plasma arc is the main arc and the inter-wire arc is the vice arc, to realize the separate control of the heat input to the workpiece,arc force, and droplet transfer. To reveal the electrical characteristics of the inter-wire arc under the action of the plasma arc, in this study, rotating probes are used to sweep across the plasma arc. When the probes rotate into the plasma arc, a circuit is formed, and the electrical characteristics of the inter-wire arc are indirectly analyzed according to the circuit: the probe centering current and input voltage are used as the physical quantities. The results show that at a certain wire feed rate, the inter-wire arc current increases with increasing input voltage. When the input voltage is low, the wire feed rate has no obvious e ect on the inter-wire arc current. At a higher input voltage, where the wire feed rate is high, the inter-wire arc current decreases. With the increase in the plasma arc current, the inter-wire arc current first increases quickly and then increases slowly, and simultaneously, the striking arc time becomes longer.With the increase in the interval between the nozzle and the workpiece, the inter-wire arc current increases, but when the arc length increases to a certain limit, the slope of the welding current clearly declines.
