Gasification is a highly effective technology for converting biomass into fuel gas or syngas.While various gas-ifiers have been commercialized for fuel gas production,mitigating tar formation in gasifiers remains chal...Gasification is a highly effective technology for converting biomass into fuel gas or syngas.While various gas-ifiers have been commercialized for fuel gas production,mitigating tar formation in gasifiers remains chal-lenging.This review is devoted to summarizing the general strategies adopted in various gasifiers to reduce tar formation for high-efficiency clean gasification.For single-bed and staged-gasification processes,their low-tar strategies are typically different.In the single-bed processes,the low-tar strategies involve in-bed intensifica-tion achieved by controlling flow directions of gas and particles inside the gasifier.During the gasification,these two components often have different temperatures to facilitate thermochemical interactions between them.Meanwhile,the two-stage gasifiers are generally designed to decouple pyrolysis,gasification and tar cracking reactions for maximizing the benefits(such as yield and efficiency)realized from the interactions among these reactions.In addition to minimizing tar formation,the approach of reaction decoupling can also raise the calorific value of product gas,even without use of oxygen,and/or improve the adaptability of gasification technology to the feedstocks with various moisture contents and particle sizes.The reanalysis based on those essential low-tar strategies is expected to gain alternative insights into the reaction principles implicated in most advanced biomass gasification technologies.展开更多
AIM To investigate the role of calmodulin-dependent protein kinase Ⅱ(Ca MKⅡ) in colon cancer growth,migration and invasion.METHODS Ca MKⅡ expression in colon cancer and paracancerous tissues was evaluated via immun...AIM To investigate the role of calmodulin-dependent protein kinase Ⅱ(Ca MKⅡ) in colon cancer growth,migration and invasion.METHODS Ca MKⅡ expression in colon cancer and paracancerous tissues was evaluated via immunochemistry. Transcriptional and posttranscriptional levels of Ca MKⅡin tissue samples and MMP2,MMP9 and TIMP-1 expression in the human colon cancer cell line HCT116 were assessed by q RTPCR and western blot. Cell proliferation was detected with the MTT assay. Cancer cell migration and invasion were investigated with the Transwell culture system and woundhealing assay.RESULTS We first demonstrated that CaMK Ⅱ was ove rexpressed in human colon cancers and was associated with cancer differentiation. In the human colon cancer cell line HCT116,the Ca MKII-specific inhibitor KN93,but not its inactive analogue KN92,decreased cancer cell proliferation. Furthermore,KN93 also significantly prohibited HCT116 cell migration and invasion. The specific inhibition of ERK1/2 or p38 decreased the proliferation and migration of colon cancer cells.CONCLUSION Our findings highlight Ca MKⅡ as a potential critical mediator in human colon tumor development and metastasis.展开更多
AIM: To study the expression of ether à go-go (Eag1) potassium channel in colorectal cancer and the relation- ship between their expression and clinico-pathological features. METHODS: The expression levels of Eag...AIM: To study the expression of ether à go-go (Eag1) potassium channel in colorectal cancer and the relation- ship between their expression and clinico-pathological features. METHODS: The expression levels of Eag1 protein were determined in 76 cancer tissues with paired non- cancerous matched tissues as well as 9 colorectal adenoma tissues by immunohistochemistry. Eag1 mRNA expression was detected in 13 colorectal cancer tissues with paired non-cancerous matched tissues and 4 colorectal adenoma tissues as well as two colorectal cancer cell lines (LoVo and HT-29) by reverse transcription PCR. RESULTS: The frequency of positive expression of Eag1 protein was 76.3% (58/76) and Eag1 mRNA was 76.9% (10/13) in colorectal cancer tissue. Expression level of Eag1 protein was dependent on the tumor size, lymphatic node metastasis, other organ metastases and Dukes’ stage (P < 0.05), while not dependent on age, sex, site and degree of differentiation. Eag1 protein and mRNA were negative in normal colorectal tissue, and absolutely negative in colorectal adenomas except that one case was positively stained for Eag1 protein. CONCLUSION: Eag1 protein and mRNA are aberrantly expressed in colorectal cancer and occasionally expressed in colorectal adenoma. The high frequency of expression of Eag1 in tumors and the restriction of normal expression to the brain suggest the potential of this protein for diagnostic, prognostic and therapeutic purposes.展开更多
Aeolian sediments are widely distributed in the Qaidam Basin, northeastern Qinghai-Ti^tan Plateau （QTP）. The pale（xiunes are mainly located at the southeastern, middle and southwestem Qaidam Basin. However, ages of...Aeolian sediments are widely distributed in the Qaidam Basin, northeastern Qinghai-Ti^tan Plateau （QTP）. The pale（xiunes are mainly located at the southeastern, middle and southwestem Qaidam Basin. However, ages ofpaleodunes in the middle and southwestern Qaidam Basin have not been well studied, although they are close to and might connect to the evolution of salt lakes in the cenWal basin. In this study, we use single aliquot regeneration （SAR） protocol of Optically Stimulated Luminescence （OSL） to date the dune sand in these two regions. The results show that： （1） Sand accumulation in these regions started at ca. 4-3 ka and lasted to ca. 0.5 ka when they were stabilized, due to the arid climate in the late Holocene. （2） The underlying fluvial sand was fomaed during deghcialion at 12.6±0.8 ka. （3） The stabilization pe- riods of the paleodunes correspond to stages of glacier advance in the northeastem QTP, during which lower temperatures caused the decrease of evapomlion and increase of the effective moisttwe, leading to an increase of vegetation cover and stabilizalion of the dunes.展开更多
The effects of high pressure rheo-squeeze casting(HPRC) on the Fe-rich phases(FRPs) and mechanical properties of Al-17 Si-(1,1.5)Fe alloys were investigated. The alloy melts were first treated by ultrasonic vibration(...The effects of high pressure rheo-squeeze casting(HPRC) on the Fe-rich phases(FRPs) and mechanical properties of Al-17 Si-(1,1.5)Fe alloys were investigated. The alloy melts were first treated by ultrasonic vibration(UV) and then formed by high-pressure squeeze casting(HPSC). The FRPs in the as-cast HPSC Al-17 Si-1 Fe alloys only contained a long, needle-shaped β-Al5 Fe Si phase at 0 MPa. In addition to the β-Al5 Fe Si phase, the HPSC Al-17 Si-1.5 Fe alloy also contained the plate-shaped δ-Al4 Fe Si2 phase. A fine, block-shaped δ-Al4 Fe Si2 phase was formed in the Al-17 Si-1 Fe alloy treated by UV. The size of FRPs decreased with increasing pressure. After UV treatment, solidification under pressure led to further refinement of the FRPs. Considering alloy samples of the same composition, the ultimate tensile strength(UTS) of the HPRC samples was higher than that of the HPSC samples, and the UTS increased with increasing pressure. The UTS of the Al-17 Si-1 Fe alloy formed by HPSC exceeded that of the Al-17 Si-1.5 Fe alloy formed in the same manner under the same pressure. Conversely, the UTS of the Al-17 Si-1 Fe alloy formed by HPRC decreased to a value lower than that of the Al-17 Si-1.5 Fe alloy formed in the same manner.展开更多
We examined a new method for visualization of the primo vascular system in the rat brain involving lateral ventricle injection of trypan blue. Results showed that the primo vascular system in the lateral ventricles an...We examined a new method for visualization of the primo vascular system in the rat brain involving lateral ventricle injection of trypan blue. Results showed that the primo vascular system in the lateral ventricles and arachnoid mater of the brain were preferentially stained relative to blood vessels and fascia. The primo-vessels along blood vessels in the brain were clearly exhibited. In addition, the primo vascular system was evident between the fourth ventricle and the quadrigeminal cistern. Our experimental findings indicate that this new technique of lateral ventricle injection of trypan blue can visualize the primo vascular system in lateral ventricles and arachnoid mater of rats in situ.展开更多
Expansions of trinucleotide or hexanucleotide repeats lead to several neurodegenerative disorders,including Huntington disease[caused by expanded CAG repeats(CAGr)in the HTT gene],and amyotrophic lateral sclerosis[ALS...Expansions of trinucleotide or hexanucleotide repeats lead to several neurodegenerative disorders,including Huntington disease[caused by expanded CAG repeats(CAGr)in the HTT gene],and amyotrophic lateral sclerosis[ALS,possibly caused by expanded GGGGCC repeats(G4C2r)in the C9ORF72 gene],of which the molecular mechanisms remain unclear.Here,we demonstrated that lowering the Drosophila homologue of tau protein(dtau)significantly rescued in vivo neurodegeneration,motor performance impairments,and the shortened life-span in Drosophila expressing expanded CAGr or expanded G4C2r.Expression of human tau(htau4 R)restored the disease-related phenotypes that had been mitigated by the loss of dtau,suggesting an evolutionarily-conserved role of tau in neurodegeneration.We further revealed that G4C2r expression increased tau accumulation by inhibiting autophagosome-lysosome fusion,possibly due to lowering the level of BAG3,a regulator of autophagy and tau.Taken together,our results reveal a novel mechanism by which expanded G4C2r causes neurodegeneration via an evolutionarily-conserved mechanism.Our findings provide novel autophagy-related mechanistic insights into C9ORF72-ALS and possible entry points to disease treatment.展开更多
Nano-ceramic particles are generally difficult to add into molten metal because of poor wettability. Nano-SiC particles reinforced A356 aluminum alloy composites were prepared by a new complex process, i.e., a molten-...Nano-ceramic particles are generally difficult to add into molten metal because of poor wettability. Nano-SiC particles reinforced A356 aluminum alloy composites were prepared by a new complex process, i.e., a molten-metal process combined with high energy ball milling and ultrasonic vibration methods. The nano particles were β-SiCp with an average diameter of 40 nm, and pre-oxidized at about 850 ℃ to form an oxide layer with a thickness of approximately 3 nm. The mm-sized composite granules containing nano-SiCp were firstly produced by milling the mixture of oxidized nano-SiCp and pure Al powders, and then were remelted in the matrix-metal melt with mechanical stirring and treated by ultrasonic vibration to prepare the composite. SEM analysis results show that the nano-SiC particles are distributed uniformly in the matrix and no serious agglomeration is observed. The tensile strength and elongation of the composite with 2wt.% nano-SiCp in as-cast state are 226 MPa and 5.5％, improved by 20％ and 44％, respectively, compared with the A356 alloy.展开更多
AIM： To investigate the effects of KN-93, a CaMKⅡ selective inhibitor on cell proliferation and the expression of p53 or p21 protein in human hepatic stellate cells. METHODS： Human hepatic stellate cells （LX-2） w...AIM： To investigate the effects of KN-93, a CaMKⅡ selective inhibitor on cell proliferation and the expression of p53 or p21 protein in human hepatic stellate cells. METHODS： Human hepatic stellate cells （LX-2） were incubated with various concentrations （0-50 μmol/L） of KN-93 or its inactive derivative, KN-92. Cell proliferation was measured by CCK-8 assay, and the expression of two cell cycle regulators, p53 and p21, was determined by SDS-PAGE and Western blotting. RESULTS： KN-93 （5-50 μmol/L） decreased the proliferation of human hepatic stellate cells in a dosedependent manner from 81.76% （81.76% ± 2.58% vs 96.63% ± 2.69%, P 〈 0.05） to 27.15% （27.15% ± 2.86% vs 96.59% ± 2.44%, P 〈 0.01） after 24 h treatment. Incubation of 10 μmol/L KN-93 induced the cell growth reduction in a time-dependent manner from 78.27% at 8 h to 11.48% at 48 h. However, KN-92, an inactive derivative of KN-93, did not inhibit cell proliferation effectively. Moreover, analysis of cell cycle regulator expression revealed that KN-93 rather than KN-92 reduced the expression of p53 and p21. CONCLUSION： KN-93 has potent inhibitory effect on proliferation of LX-2 cells by modulating the expression of two special cell cycle regulators, p53 and p21.展开更多
BACKGROUND Non-Hodgkin’s lymphoma(NHL)can involve extralymphatic organs,resulting in diverse clinical manifestations,especially if the endocrine organs are affected.This type of involvement can often be difficult to ...BACKGROUND Non-Hodgkin’s lymphoma(NHL)can involve extralymphatic organs,resulting in diverse clinical manifestations,especially if the endocrine organs are affected.This type of involvement can often be difficult to detect accurately.Until now,no patients with NHL and concomitant bilateral adrenal and hypothalamic involvement have been reported.The purpose of this article is to discuss the diagnosis and treatment of lymphoma with bilateral adrenal gland and hypothalamic involvement so as to help physicians avoid misdiagnosis and missed diagnosis.CASE SUMMARY We describe a case of a 52-years-old male patient with bilateral adrenal masses,who presented with a fever of unknown origin on admission.Subsequently,hypopituitarism of the anterior pituitary followed by posterior pituitary developed.18fluorine-fluorodeoxyglucose positron emission tomography/computed tomography(PET/CT)showed lesions with a high metabolism in both adrenal glands,hypothalamus,left supraclavicular lymph nodes,and other organs.The etiological diagnosis was determined based on a left supraclavicular lymph node biopsy.The patient,who eventually present with panhypopituitarism,was finally diagnosed with diffuse large B cell lymphoma with bilateral adrenal gland and hypothalamic involvement.After immunochemotherapy,glucocorticoids administration and desmopressin acetate replacement therapy,the symptoms of fever and panhypopituitarism improved,and all the lesions reduced in size.CONCLUSION This report demonstrates that,although synchronous involvement of two endocrine organs is rare in NHL,extra caution should be taken when dysfunction occurs in multiple endocrine organs.展开更多
Clarifying the persistence time of seedlings of dominant species under continual drought will help us understand responses of ecosystems to global climate change and improve revegetation efforts. Drought tolerance of ...Clarifying the persistence time of seedlings of dominant species under continual drought will help us understand responses of ecosystems to global climate change and improve revegetation efforts. Drought tolerance of four dominant psammophytic shrub species occurring in different environments was studied in the semi-arid areas of Inner Mongolian grasslands. Seedlings of Hedysarum laeve, Caragana korshinskii, Artemisia sphaerocephala and Artemisia ordosica were grown under four air temperature regimes （night/day： 12.5/22.5℃, 15/25℃, 17.5/27.5℃ and 20/30℃） within climate （air temperature and humidity） controlled, naturally lit glasshouses with a night/day relative humidity of 70%/50%. Pots were watered to field capacity for each temperature treatment. Soil water condition was monitored by weighting each pot every day using an electronic balance. Date of seedling death for each treatment was recorded and the dead plants were harvested. Plant dry weights were determined after oven drying at 80℃ for 3 days. Two Artemisia species had higher growth rates than H. laeve and C. korshinskii, and the growth of all four species increased with increasing temperatures. The two Artemisia species had the highest leaf biomass increment, followed by C. korshinskii, and then H. laeve. Shoot biomass increment was higher for A. ordosica and C. korshinskii, intermediate for A. sphaerocephala and lowest for H. laeve. C. korshinskii had the highest root biomass increment. The final soil water content at death for all four species varied from 1% to 2%. C. korshinskii, A. sphaerocephala, H. laeve and A. ordosica survived for 25-43, 24-41, 26-41 and 24-37 days without watering, respectively. C. korshinskii, A. sphaerocephala, H. Laeve, and A. ordosica seedlings survived longer at the lowest temperatures （12.5/22.5℃） than at the highest temperatures （20/30℃） by 18, 17, 15 and 13 days, respectively. Increased climatic temperatures induce the death of seedlings in years with long intervals between rainfall events. The adaptation of seedlings to droughts should be emphasized in revegetation efforts in the Ordos Plateau, Inner Mongolia.展开更多
In this research, the in situ Si and Fe-rich particles reinforced Al matrix composites were fabricated by rheocasting （RC） process assisted with ultrasonic vibration （USV）. After USV treatment, the polygonal prima...In this research, the in situ Si and Fe-rich particles reinforced Al matrix composites were fabricated by rheocasting （RC） process assisted with ultrasonic vibration （USV）. After USV treatment, the polygonal primary Si crystals were refined into particles with average diameter of about 15-23 μm, and the fraction of primary Si declined to about 5.4-6.5 vol%. The coarse plate-like δ-Al4（Fe,Mn）Si2 phase was transformed into fine particles with average diameter of about 17-20 μm, and the fraction of particle-like Fe-bearing particles is about 3.6-5.3 vol%. The ultimate tensile strength of the RC composites increases with the increase of Fe content at 350 ℃. The increase of the elevated temperature strength of the composites is mainly attributed to the refinement of δ-Al4（（Fe,Mn）Si2 phase and the increase of the volume fraction of the Fe-bearing compounds. Compared with the composites without USV, the RC composites assisted with USV have thinner mechanical mixing layer in wear test, which corresponds to smaller wear rate.展开更多
Hepatitis B-associated hepatocellular carcinoma (HBV-HCC) remains an intractable high-mortality solidtumor cancer that accounted for 42% of global HCC cases in 2019. Despite some developments in systemic therapy,only ...Hepatitis B-associated hepatocellular carcinoma (HBV-HCC) remains an intractable high-mortality solidtumor cancer that accounted for 42% of global HCC cases in 2019. Despite some developments in systemic therapy,only a small subset of late-stage HCC patients responds positively to recently developed therapeutic innovations.MicroRNAs (miRNAs) act as an ancillary epigenetic system that can regulate genome expression in all cancerpathways including HCC. The molecular mechanisms of miRNA regulation in cancer pathogenesis offered researchersa new approach that was widely hoped would translate into miRNA-based drugs and diagnostics. Thirty years on,miRNA-based diagnostic and therapeutic agents for HCC remain a work-in-progress (WIP) and no current miRNAHCC clinical trial has progressed to Phase 4. The question remains why this is the case after 30 years and what is theway forward. The major findings and contribution of this paper are that it illustrates the complexity of the HBVmiRNA interactome in HBV-HCC in all cellular processes, as well as the ancillary role of miRNA in the epigeneticand immune systems. This is combined with a review of the outcomes and problems of clinical trials, to explain whymiRNA therapeutics and diagnostics have not progressed to approved drugs or serum-based diagnostic tests. The wayforward suggests a radical rethink might be so that involves the incorporation of AI, bioinformatics, andnanotechnology to solve the problem.展开更多
Colorectal cancer(CRC) is the second most common cause of cancer death worldwide. Distant metastasis is the major cause of death in patients with CRC. During progression to metastasis in which malignant cells dissemin...Colorectal cancer(CRC) is the second most common cause of cancer death worldwide. Distant metastasis is the major cause of death in patients with CRC. During progression to metastasis in which malignant cells disseminate from the primary tumor to seeding other organs, a multistep process is involved. Cancer cells proliferate, invade microenvironment, enter into the blood circulation, then survive and colonize into distant organs. Micro RNAs(mi RNAs) and epithelial-mesenchymal transition(EMT) are key regulators and mechanism in tumorigenesis and cancer metastasis. We review the roles of EMT and micro RNAs, especially EMT related micro RNAs in the metastatic pathway of CRC. Micro RNAs provide us a set of potential therapeutic applications and molecular target for CRC.展开更多
AbstractThe loading sequence effect in constructing a fatigue loading spectrum has been paidattention to by experts at home and abroad for many years. In this paper, loading sequcnceand arrangement effects are analyse...AbstractThe loading sequence effect in constructing a fatigue loading spectrum has been paidattention to by experts at home and abroad for many years. In this paper, loading sequcnceand arrangement effects are analysed for two dimensional distributional spectrum. It isderived that loading sequence effect is little concerned with the approaches to constructingfatigue spectrum and varies only along with the total mean value of a loading spectrumthough it has a great effect on fatigue lives of components. So the loading arrangement ef-fect is small, and the approaches to constructing fatigue spectrum have little effect on lives.展开更多
A new, more actual approach for omitting small loads in a loading history was pres-ented according to crack closure, and load interactive effects which are large on damage of com-ponents were studied. Intrinsic period...A new, more actual approach for omitting small loads in a loading history was pres-ented according to crack closure, and load interactive effects which are large on damage of com-ponents were studied. Intrinsic periodic spectrum block representing a damage element of a loadhistory, a new concept, was put out. It has been proven by theoretic analysis and tests that themodes of constructing fatigue loading spectrum have little effect on damage of components,which will change the incomplete knowledges on constructing fatigue spectrum ago.展开更多
基金supported by Youth Fund of National Natural Science Foundation of China(NO.22108175)Basic scientific research Project of colleges and universities of Liaoning Provincial Department of Educa-tion(No.LJKMZ20220798)+1 种基金National Natural Science Foundation of China(No.U1903130)Natural Science Foundation of Liaoning province(No.2021-NLTS-12-09),China,and JST Grant Number JPMJPF2104,Japan.
文摘Gasification is a highly effective technology for converting biomass into fuel gas or syngas.While various gas-ifiers have been commercialized for fuel gas production,mitigating tar formation in gasifiers remains chal-lenging.This review is devoted to summarizing the general strategies adopted in various gasifiers to reduce tar formation for high-efficiency clean gasification.For single-bed and staged-gasification processes,their low-tar strategies are typically different.In the single-bed processes,the low-tar strategies involve in-bed intensifica-tion achieved by controlling flow directions of gas and particles inside the gasifier.During the gasification,these two components often have different temperatures to facilitate thermochemical interactions between them.Meanwhile,the two-stage gasifiers are generally designed to decouple pyrolysis,gasification and tar cracking reactions for maximizing the benefits(such as yield and efficiency)realized from the interactions among these reactions.In addition to minimizing tar formation,the approach of reaction decoupling can also raise the calorific value of product gas,even without use of oxygen,and/or improve the adaptability of gasification technology to the feedstocks with various moisture contents and particle sizes.The reanalysis based on those essential low-tar strategies is expected to gain alternative insights into the reaction principles implicated in most advanced biomass gasification technologies.
基金Supported by the National Natural Science Foundation of China,No.81302131
文摘AIM To investigate the role of calmodulin-dependent protein kinase Ⅱ(Ca MKⅡ) in colon cancer growth,migration and invasion.METHODS Ca MKⅡ expression in colon cancer and paracancerous tissues was evaluated via immunochemistry. Transcriptional and posttranscriptional levels of Ca MKⅡin tissue samples and MMP2,MMP9 and TIMP-1 expression in the human colon cancer cell line HCT116 were assessed by q RTPCR and western blot. Cell proliferation was detected with the MTT assay. Cancer cell migration and invasion were investigated with the Transwell culture system and woundhealing assay.RESULTS We first demonstrated that CaMK Ⅱ was ove rexpressed in human colon cancers and was associated with cancer differentiation. In the human colon cancer cell line HCT116,the Ca MKII-specific inhibitor KN93,but not its inactive analogue KN92,decreased cancer cell proliferation. Furthermore,KN93 also significantly prohibited HCT116 cell migration and invasion. The specific inhibition of ERK1/2 or p38 decreased the proliferation and migration of colon cancer cells.CONCLUSION Our findings highlight Ca MKⅡ as a potential critical mediator in human colon tumor development and metastasis.
文摘AIM: To study the expression of ether à go-go (Eag1) potassium channel in colorectal cancer and the relation- ship between their expression and clinico-pathological features. METHODS: The expression levels of Eag1 protein were determined in 76 cancer tissues with paired non- cancerous matched tissues as well as 9 colorectal adenoma tissues by immunohistochemistry. Eag1 mRNA expression was detected in 13 colorectal cancer tissues with paired non-cancerous matched tissues and 4 colorectal adenoma tissues as well as two colorectal cancer cell lines (LoVo and HT-29) by reverse transcription PCR. RESULTS: The frequency of positive expression of Eag1 protein was 76.3% (58/76) and Eag1 mRNA was 76.9% (10/13) in colorectal cancer tissue. Expression level of Eag1 protein was dependent on the tumor size, lymphatic node metastasis, other organ metastases and Dukes’ stage (P < 0.05), while not dependent on age, sex, site and degree of differentiation. Eag1 protein and mRNA were negative in normal colorectal tissue, and absolutely negative in colorectal adenomas except that one case was positively stained for Eag1 protein. CONCLUSION: Eag1 protein and mRNA are aberrantly expressed in colorectal cancer and occasionally expressed in colorectal adenoma. The high frequency of expression of Eag1 in tumors and the restriction of normal expression to the brain suggest the potential of this protein for diagnostic, prognostic and therapeutic purposes.
基金supported by SKLLQG(SKLLQG1217)China Postdoctoral Science Foundation founded project(2012M521822)NSFC(41290252)
文摘Aeolian sediments are widely distributed in the Qaidam Basin, northeastern Qinghai-Ti^tan Plateau （QTP）. The pale（xiunes are mainly located at the southeastern, middle and southwestem Qaidam Basin. However, ages ofpaleodunes in the middle and southwestern Qaidam Basin have not been well studied, although they are close to and might connect to the evolution of salt lakes in the cenWal basin. In this study, we use single aliquot regeneration （SAR） protocol of Optically Stimulated Luminescence （OSL） to date the dune sand in these two regions. The results show that： （1） Sand accumulation in these regions started at ca. 4-3 ka and lasted to ca. 0.5 ka when they were stabilized, due to the arid climate in the late Holocene. （2） The underlying fluvial sand was fomaed during deghcialion at 12.6±0.8 ka. （3） The stabilization pe- riods of the paleodunes correspond to stages of glacier advance in the northeastem QTP, during which lower temperatures caused the decrease of evapomlion and increase of the effective moisttwe, leading to an increase of vegetation cover and stabilizalion of the dunes.
基金financially supported by the National Natural Science Foundation of China (No. 51605342)the China Postdoctoral Science Foundation (No. 2015M572135)the Open Research Fund Program of Hubei Provincial Key Laboratory of Chemical Equipment Intensification and Intrinsic Safety (No. 2016KA01)
文摘The effects of high pressure rheo-squeeze casting(HPRC) on the Fe-rich phases(FRPs) and mechanical properties of Al-17 Si-(1,1.5)Fe alloys were investigated. The alloy melts were first treated by ultrasonic vibration(UV) and then formed by high-pressure squeeze casting(HPSC). The FRPs in the as-cast HPSC Al-17 Si-1 Fe alloys only contained a long, needle-shaped β-Al5 Fe Si phase at 0 MPa. In addition to the β-Al5 Fe Si phase, the HPSC Al-17 Si-1.5 Fe alloy also contained the plate-shaped δ-Al4 Fe Si2 phase. A fine, block-shaped δ-Al4 Fe Si2 phase was formed in the Al-17 Si-1 Fe alloy treated by UV. The size of FRPs decreased with increasing pressure. After UV treatment, solidification under pressure led to further refinement of the FRPs. Considering alloy samples of the same composition, the ultimate tensile strength(UTS) of the HPRC samples was higher than that of the HPSC samples, and the UTS increased with increasing pressure. The UTS of the Al-17 Si-1 Fe alloy formed by HPSC exceeded that of the Al-17 Si-1.5 Fe alloy formed in the same manner under the same pressure. Conversely, the UTS of the Al-17 Si-1 Fe alloy formed by HPRC decreased to a value lower than that of the Al-17 Si-1.5 Fe alloy formed in the same manner.
基金the National Natural Science Foundation of China for Youths (General Program),No.30801464the National Basic Research Program of China (973 Program),No.2007CB512705the GIST Systems Biology Program of Korea in 2010
文摘We examined a new method for visualization of the primo vascular system in the rat brain involving lateral ventricle injection of trypan blue. Results showed that the primo vascular system in the lateral ventricles and arachnoid mater of the brain were preferentially stained relative to blood vessels and fascia. The primo-vessels along blood vessels in the brain were clearly exhibited. In addition, the primo vascular system was evident between the fourth ventricle and the quadrigeminal cistern. Our experimental findings indicate that this new technique of lateral ventricle injection of trypan blue can visualize the primo vascular system in lateral ventricles and arachnoid mater of rats in situ.
基金the National Natural Science Foundation of China(81925012 and 31961130379)a Newton Advanced Fellowship(NAF_R1_191045)。
文摘Expansions of trinucleotide or hexanucleotide repeats lead to several neurodegenerative disorders,including Huntington disease[caused by expanded CAG repeats(CAGr)in the HTT gene],and amyotrophic lateral sclerosis[ALS,possibly caused by expanded GGGGCC repeats(G4C2r)in the C9ORF72 gene],of which the molecular mechanisms remain unclear.Here,we demonstrated that lowering the Drosophila homologue of tau protein(dtau)significantly rescued in vivo neurodegeneration,motor performance impairments,and the shortened life-span in Drosophila expressing expanded CAGr or expanded G4C2r.Expression of human tau(htau4 R)restored the disease-related phenotypes that had been mitigated by the loss of dtau,suggesting an evolutionarily-conserved role of tau in neurodegeneration.We further revealed that G4C2r expression increased tau accumulation by inhibiting autophagosome-lysosome fusion,possibly due to lowering the level of BAG3,a regulator of autophagy and tau.Taken together,our results reveal a novel mechanism by which expanded G4C2r causes neurodegeneration via an evolutionarily-conserved mechanism.Our findings provide novel autophagy-related mechanistic insights into C9ORF72-ALS and possible entry points to disease treatment.
基金financially supported by the National Natural Science Foundation of China(No.51574129)Technological Innovation Special Project of Hubei Province(No.2017AAA110)
文摘Nano-ceramic particles are generally difficult to add into molten metal because of poor wettability. Nano-SiC particles reinforced A356 aluminum alloy composites were prepared by a new complex process, i.e., a molten-metal process combined with high energy ball milling and ultrasonic vibration methods. The nano particles were β-SiCp with an average diameter of 40 nm, and pre-oxidized at about 850 ℃ to form an oxide layer with a thickness of approximately 3 nm. The mm-sized composite granules containing nano-SiCp were firstly produced by milling the mixture of oxidized nano-SiCp and pure Al powders, and then were remelted in the matrix-metal melt with mechanical stirring and treated by ultrasonic vibration to prepare the composite. SEM analysis results show that the nano-SiC particles are distributed uniformly in the matrix and no serious agglomeration is observed. The tensile strength and elongation of the composite with 2wt.% nano-SiCp in as-cast state are 226 MPa and 5.5％, improved by 20％ and 44％, respectively, compared with the A356 alloy.
文摘AIM： To investigate the effects of KN-93, a CaMKⅡ selective inhibitor on cell proliferation and the expression of p53 or p21 protein in human hepatic stellate cells. METHODS： Human hepatic stellate cells （LX-2） were incubated with various concentrations （0-50 μmol/L） of KN-93 or its inactive derivative, KN-92. Cell proliferation was measured by CCK-8 assay, and the expression of two cell cycle regulators, p53 and p21, was determined by SDS-PAGE and Western blotting. RESULTS： KN-93 （5-50 μmol/L） decreased the proliferation of human hepatic stellate cells in a dosedependent manner from 81.76% （81.76% ± 2.58% vs 96.63% ± 2.69%, P 〈 0.05） to 27.15% （27.15% ± 2.86% vs 96.59% ± 2.44%, P 〈 0.01） after 24 h treatment. Incubation of 10 μmol/L KN-93 induced the cell growth reduction in a time-dependent manner from 78.27% at 8 h to 11.48% at 48 h. However, KN-92, an inactive derivative of KN-93, did not inhibit cell proliferation effectively. Moreover, analysis of cell cycle regulator expression revealed that KN-93 rather than KN-92 reduced the expression of p53 and p21. CONCLUSION： KN-93 has potent inhibitory effect on proliferation of LX-2 cells by modulating the expression of two special cell cycle regulators, p53 and p21.
文摘BACKGROUND Non-Hodgkin’s lymphoma(NHL)can involve extralymphatic organs,resulting in diverse clinical manifestations,especially if the endocrine organs are affected.This type of involvement can often be difficult to detect accurately.Until now,no patients with NHL and concomitant bilateral adrenal and hypothalamic involvement have been reported.The purpose of this article is to discuss the diagnosis and treatment of lymphoma with bilateral adrenal gland and hypothalamic involvement so as to help physicians avoid misdiagnosis and missed diagnosis.CASE SUMMARY We describe a case of a 52-years-old male patient with bilateral adrenal masses,who presented with a fever of unknown origin on admission.Subsequently,hypopituitarism of the anterior pituitary followed by posterior pituitary developed.18fluorine-fluorodeoxyglucose positron emission tomography/computed tomography(PET/CT)showed lesions with a high metabolism in both adrenal glands,hypothalamus,left supraclavicular lymph nodes,and other organs.The etiological diagnosis was determined based on a left supraclavicular lymph node biopsy.The patient,who eventually present with panhypopituitarism,was finally diagnosed with diffuse large B cell lymphoma with bilateral adrenal gland and hypothalamic involvement.After immunochemotherapy,glucocorticoids administration and desmopressin acetate replacement therapy,the symptoms of fever and panhypopituitarism improved,and all the lesions reduced in size.CONCLUSION This report demonstrates that,although synchronous involvement of two endocrine organs is rare in NHL,extra caution should be taken when dysfunction occurs in multiple endocrine organs.
基金supported by the National Basic Research Program of China (2009CB825103)
文摘Clarifying the persistence time of seedlings of dominant species under continual drought will help us understand responses of ecosystems to global climate change and improve revegetation efforts. Drought tolerance of four dominant psammophytic shrub species occurring in different environments was studied in the semi-arid areas of Inner Mongolian grasslands. Seedlings of Hedysarum laeve, Caragana korshinskii, Artemisia sphaerocephala and Artemisia ordosica were grown under four air temperature regimes （night/day： 12.5/22.5℃, 15/25℃, 17.5/27.5℃ and 20/30℃） within climate （air temperature and humidity） controlled, naturally lit glasshouses with a night/day relative humidity of 70%/50%. Pots were watered to field capacity for each temperature treatment. Soil water condition was monitored by weighting each pot every day using an electronic balance. Date of seedling death for each treatment was recorded and the dead plants were harvested. Plant dry weights were determined after oven drying at 80℃ for 3 days. Two Artemisia species had higher growth rates than H. laeve and C. korshinskii, and the growth of all four species increased with increasing temperatures. The two Artemisia species had the highest leaf biomass increment, followed by C. korshinskii, and then H. laeve. Shoot biomass increment was higher for A. ordosica and C. korshinskii, intermediate for A. sphaerocephala and lowest for H. laeve. C. korshinskii had the highest root biomass increment. The final soil water content at death for all four species varied from 1% to 2%. C. korshinskii, A. sphaerocephala, H. laeve and A. ordosica survived for 25-43, 24-41, 26-41 and 24-37 days without watering, respectively. C. korshinskii, A. sphaerocephala, H. Laeve, and A. ordosica seedlings survived longer at the lowest temperatures （12.5/22.5℃） than at the highest temperatures （20/30℃） by 18, 17, 15 and 13 days, respectively. Increased climatic temperatures induce the death of seedlings in years with long intervals between rainfall events. The adaptation of seedlings to droughts should be emphasized in revegetation efforts in the Ordos Plateau, Inner Mongolia.
基金financially supported by the National Basic Research Program of China (No.2012CB619600)the Fundamental Research Funds for the Central Universities (No.2014QNRC003)
文摘In this research, the in situ Si and Fe-rich particles reinforced Al matrix composites were fabricated by rheocasting （RC） process assisted with ultrasonic vibration （USV）. After USV treatment, the polygonal primary Si crystals were refined into particles with average diameter of about 15-23 μm, and the fraction of primary Si declined to about 5.4-6.5 vol%. The coarse plate-like δ-Al4（Fe,Mn）Si2 phase was transformed into fine particles with average diameter of about 17-20 μm, and the fraction of particle-like Fe-bearing particles is about 3.6-5.3 vol%. The ultimate tensile strength of the RC composites increases with the increase of Fe content at 350 ℃. The increase of the elevated temperature strength of the composites is mainly attributed to the refinement of δ-Al4（（Fe,Mn）Si2 phase and the increase of the volume fraction of the Fe-bearing compounds. Compared with the composites without USV, the RC composites assisted with USV have thinner mechanical mixing layer in wear test, which corresponds to smaller wear rate.
文摘Hepatitis B-associated hepatocellular carcinoma (HBV-HCC) remains an intractable high-mortality solidtumor cancer that accounted for 42% of global HCC cases in 2019. Despite some developments in systemic therapy,only a small subset of late-stage HCC patients responds positively to recently developed therapeutic innovations.MicroRNAs (miRNAs) act as an ancillary epigenetic system that can regulate genome expression in all cancerpathways including HCC. The molecular mechanisms of miRNA regulation in cancer pathogenesis offered researchersa new approach that was widely hoped would translate into miRNA-based drugs and diagnostics. Thirty years on,miRNA-based diagnostic and therapeutic agents for HCC remain a work-in-progress (WIP) and no current miRNAHCC clinical trial has progressed to Phase 4. The question remains why this is the case after 30 years and what is theway forward. The major findings and contribution of this paper are that it illustrates the complexity of the HBVmiRNA interactome in HBV-HCC in all cellular processes, as well as the ancillary role of miRNA in the epigeneticand immune systems. This is combined with a review of the outcomes and problems of clinical trials, to explain whymiRNA therapeutics and diagnostics have not progressed to approved drugs or serum-based diagnostic tests. The wayforward suggests a radical rethink might be so that involves the incorporation of AI, bioinformatics, andnanotechnology to solve the problem.
基金Supported by a grant from the National Natural Sciences Foundation of China(No.81302131)Natural Science Foundation of Hubei Province,China(No.2012FKB04432)
文摘Colorectal cancer(CRC) is the second most common cause of cancer death worldwide. Distant metastasis is the major cause of death in patients with CRC. During progression to metastasis in which malignant cells disseminate from the primary tumor to seeding other organs, a multistep process is involved. Cancer cells proliferate, invade microenvironment, enter into the blood circulation, then survive and colonize into distant organs. Micro RNAs(mi RNAs) and epithelial-mesenchymal transition(EMT) are key regulators and mechanism in tumorigenesis and cancer metastasis. We review the roles of EMT and micro RNAs, especially EMT related micro RNAs in the metastatic pathway of CRC. Micro RNAs provide us a set of potential therapeutic applications and molecular target for CRC.
文摘AbstractThe loading sequence effect in constructing a fatigue loading spectrum has been paidattention to by experts at home and abroad for many years. In this paper, loading sequcnceand arrangement effects are analysed for two dimensional distributional spectrum. It isderived that loading sequence effect is little concerned with the approaches to constructingfatigue spectrum and varies only along with the total mean value of a loading spectrumthough it has a great effect on fatigue lives of components. So the loading arrangement ef-fect is small, and the approaches to constructing fatigue spectrum have little effect on lives.
文摘A new, more actual approach for omitting small loads in a loading history was pres-ented according to crack closure, and load interactive effects which are large on damage of com-ponents were studied. Intrinsic periodic spectrum block representing a damage element of a loadhistory, a new concept, was put out. It has been proven by theoretic analysis and tests that themodes of constructing fatigue loading spectrum have little effect on damage of components,which will change the incomplete knowledges on constructing fatigue spectrum ago.
