Transcription activator-like effector nucleases （TALENs） and clustered regularly interspaced short palindromic repeats （CRISPR）/ CRISPR-associated （Cas） systems have emerged as powerful tools for genome editing ...Transcription activator-like effector nucleases （TALENs） and clustered regularly interspaced short palindromic repeats （CRISPR）/ CRISPR-associated （Cas） systems have emerged as powerful tools for genome editing in a variety of species. Here, we report, for the first time, targeted mutagenesis in Zea mays using TALENs and the CRISPR/Cas system. We designed five TALENs targeting 4 genes, namely ZmPDS, ZmlPKIA, ZmlPK, ZmMRP4, and obtained targeting efficiencies of up to 23.1% in protoplasts, and about 13.3% to 39.1% of the transgenic plants were somatic mutations. Also, we constructed two gRNAs targeting the ZmlPK gene in maize protoplasts, at frequencies of 16.4% and 19.1%, respectively. In addition, the CRISPR/Cas system induced targeted mutations in Z. mays protoplasts with efficiencies （13.1%） similar to those obtained with TALENs （9.1%）. Our results show that both TALENs and the CRISPR/Cas system can be used for genome modification in maize.展开更多
The importance of cancer stem cells （CSCs） in tumor-initiation has been firmly established in leukemia and recently reported for a variety of solid tumors. However, the role of CSCs in multistage cancer progression,...The importance of cancer stem cells （CSCs） in tumor-initiation has been firmly established in leukemia and recently reported for a variety of solid tumors. However, the role of CSCs in multistage cancer progression, particularly with respect to metastasis, has not been well-defined. Cancer metastasis requires the seeding and successful colonization of specialized CSCs at distant organs. The biology of normal stem cells and CSCs share remarkable similarities and may have important implications when applied to the study of cancer metastasis. Furthermore, overlapping sets of molecules and pathways have recently been identified to regulate both stem cell migration and cancer metastasis. These molecules constitute a complex network of cellular interactions that facilitate both the initiation of the pre-metastasis niche by the primary tumor and the formation of a nurturing organ microenvironment for migrating CSCs. In this review, we surveyed the recent advances in this dynamic field and propose a unified model of cancer progression in which CSCs assume a central role in both tumorigenesis and metastasis. Better understanding of CSCs as a fundamental component of the metastatic cascade will lead to novel therapeutic strategies against metastatic cancer.展开更多
Mobile communication standards have been developed into a new era of B5G and 6G.In recent years,low earth orbit(LEO)satellites and space Internet have become hot topics.The integrated satellite and terrestrial systems...Mobile communication standards have been developed into a new era of B5G and 6G.In recent years,low earth orbit(LEO)satellites and space Internet have become hot topics.The integrated satellite and terrestrial systems have been widely discussed by industries and academics,and even are expected to be applied in those huge constellations in construction.This paper points out the trends of two stages towards system integration of the terrestrial mobile communication and the satellite communications:to be compatible with 5G,and to be integrated within 6G.Based on analysis of the challenges of both stages,key technologies are thereafter analyzed in detail,covering both air interface currently discussed in 3GPP for B5G and also novel network architecture and related transmission technologies toward future 6G.展开更多
Background:The prevalence of Mycoplasma pneumoniae pneumonia has increased considerably in recent years.To evaluate the efficacy of combined treatment of azithromycin with intravenous immunoglo-bulin (IVIG) or methylp...Background:The prevalence of Mycoplasma pneumoniae pneumonia has increased considerably in recent years.To evaluate the efficacy of combined treatment of azithromycin with intravenous immunoglo-bulin (IVIG) or methylprednisolone in children with refractory Mycoplasma pneumoniae pneumonia (RMPP).Methods:Children with RMPP were randomly allocated to group A [intravenous azithromycin (IA)+ methylprednisolone],group B (IA+IVIG) or group C (IA alone).Following a 7-day treatment,group C patients were randomly separated into two sub-groups:group C1 (IA+methylprednisolone) and group C2 (IA+IVIG).Temperature,respiratory symptoms and signs were examined.The average febrile period after treatment (F2),average total febrile period (F3),infiltration absorption,atelectasis resolution,pleural effusion disappearance were determined.The levels of C-reactive protein (CRP),D-dimer,and lactate dehydrogenase (LDH) were measured.Results:Seven days after enrollment,the average F2 after treatment of group A was the shortest.Compared with the control group C,the combined treatment group A and B showed higher rates of infiltration absorption,atelectasis resolution and pleural effusion disappearance,while lower levels of serum CRP,D-dimer and LDH.Fourteen days after enrollment,all children with combined therapy clinically improved,and presented better laboratory results.Group C1 showed shorter F3 and lower levels of CRP and LDH than those of group C2.Overall,group A showed the shortest F3,also has the lowest CRP and LDH.Conclusions:Azithromycin with IVIG or methylprednisolone was better treatment for children with RMPP than azithromycin alone.IVIG treatment may be beneficial,especially when the efficacy of corticosteroids is insecure,thus could be considered as an alternative of primary therapeutic approaches.展开更多
AIM:To evaluate the efficacy of simple and extended cholecystectomy for mucosa(T1a) or muscularis(T1b) gallbladder(GB) cancer. METHODS:Original studies on simple and extended cholecystectomy for T1a or T1b GB cancer w...AIM:To evaluate the efficacy of simple and extended cholecystectomy for mucosa(T1a) or muscularis(T1b) gallbladder(GB) cancer. METHODS:Original studies on simple and extended cholecystectomy for T1a or T1b GB cancer were searched from MEDLINE(PubMed) ,Cochrane Library,EMBase,and CancerLit using the search terms of GB,cancer/carcinoma/tumor/neoplasm. RESULTS:Twenty-nine out of the 2312 potentially relevant publications met the eligibility criteria.Of the 1266 patients with GB cancer included in the publications,706(55.8%) and 560(44.2%) had T1a and T1b GB cancer,respectively.Simple cholecystectomy for T1a and T1b GB cancer was performed in 590(83.6%) and 375(67.0%) patients,respectively(P<0.01) .In most series,the treatment of choice was simple cholecystectomy for T1a GB cancer patients with a 5-year survival rate of 100%.Lymph node metastasis was detected in 10.9% of the T1b GB cancer patients and in 1.8%of the T1a GB cancer patients,respectively(P<0.01) .Eight patients(1.1%) with T1a GB cancer and 52 patients(9.3%) with T1b GB cancer died of recurrent GB cancer(P<0.01) . CONCLUSION:Simple cholecystectomy represents the adequate treatment of T1a GB cancer.There is no definite evidence that extended cholecystectomy is advantageous over simple cholecystectomy for T1b GB cancer.展开更多
Grain size determines grain weight and affects grain quality. Several major quantitative trait loci （QTLs） regulating grain size have been cloned; however, our understanding of the underlying mechanism that regulate...Grain size determines grain weight and affects grain quality. Several major quantitative trait loci （QTLs） regulating grain size have been cloned; however, our understanding of the underlying mechanism that regulates the size of rice grains remains fragmentary. Here, we report the cloning and characterization of a dominant QTL, GRAIN SIZE ON CHROMOSOME 2 （GS2）, which encodes Growth-Regulating Factor 4 （OsGRF4）, a transcriptional regulator. GS2 localizes to the nucleus and may act as a transcription activator. A rare mutation of GS2 affecting the binding site of a microRNA, OsmiR396c, causes elevated expression of GS2/OsGRF4. The increase in GS2 expression leads to larger cells and increased numbers of cells, which thus enhances grain weight and yield. The introduction of this rare allele of GS2/OsGRF4 into rice cultivars could significantly enhance grain weight and increase grain yield, with possible applications in breeding high-yield rice varieties.展开更多
Dear Editor, Human embryonic stem （ES） cells possess the potential to differentiate into all the cell types of the human body and provide potential applications in regenerative medicine . However, the concerns of i...Dear Editor, Human embryonic stem （ES） cells possess the potential to differentiate into all the cell types of the human body and provide potential applications in regenerative medicine . However, the concerns of immune rejection hamper transplantation therapies using human ES cells. To avoid the complications of immune rejection, diverse methods, such as somatic nuclear transfer （also called therapeutic cloning） and fusion of somatic ceils with human ES ceils , have been attempted to produce patient-specific pluripotent stem cells. Most of these approaches have resulted in little success. The generation of human iPS cells （induced展开更多
Thick and ultra-thick coal seams are main coal seams for high production rate and high efficiency in Chinese coal mines, which accounts for 44 % of the total minable coal reserve. A fully mechanized top-coal caving mi...Thick and ultra-thick coal seams are main coal seams for high production rate and high efficiency in Chinese coal mines, which accounts for 44 % of the total minable coal reserve. A fully mechanized top-coal caving mining method is a main underground coal extraction method for ultra-thick coal seams. The coal extraction technologies for coal seams less than 14 m thick were extensively used in China. However, for coal seams with thickness greater than 14 m, there have been no reported cases in the world for underground mechanical extraction with safe performance, high efficiency and high coal recovery ratio. To deal with this case, China Coal Technology ＆ Engineering Group, Datong Coal Mine Group, and other 15 organizations in China launched a fundamental and big project to develop coal mining technologies and equipment for coal seams with thicknesses greater than 14 m. After the completion of the project, a coal extraction method was developed for top-coal caving with a large mining height, as well as a ground control theory for ultra-thick coal seams. In addition, the mining technology for top-coal caving with a large mining height, the ground support technology for roadway in coal seams with a large cross-section, and the prevention and control technology for gas and fire hazards were developed and applied. Furthermore, a hydraulic support with a mining height of 5.2 m, a shearer with high reliability, and auxiliary equipment were developed and manufactured. Practical implication on the technologies and equipment developed was successfully completed at the No. 8105 coal face in the Tashan coal mine, Datong, China. The major achievements of the project are summarized as follows： 1. A top-coal caving method for ultra-thick coal seams is proposed with a cutting height of 5 m and a top-coal caving height of 15 m. A structural mechanical model of overlying strata called cantilever beam-articulated rock beam is established. Based on the model, the load resistance of the hydraulic support with a large mining heigh展开更多
AIM:Irritable bowel syndrome(IBS)is a functional bowel disorder characterized by visceral hypersensitivity and altered bowel motility.There is increasing evidence suggesting the role of inflammation in the pathogenesi...AIM:Irritable bowel syndrome(IBS)is a functional bowel disorder characterized by visceral hypersensitivity and altered bowel motility.There is increasing evidence suggesting the role of inflammation in the pathogenesis of IBS,which addresses the possibility that formerly established rat model of colitis could be used as an IBS model after the inflammation subsided. METHODS:Colitis was induced by intracolonic instillation of 4% acetic acid in male Sprague-Dawley rats.The extent of inflammation was assessed by histological examination and myeloperoxidase(MPO)activity assay.After subsidence of colitis,the rats were subjected to rectal distension and restraint stress,then the abdominal withdrawal reflex and the number of stress-induced fecal output were measured, respectively. RESULTS:At 2 days post-induction of colitis,the colon showed characteristic inflammatory changes in histology and 8-fold increase in MPO activity.At 7 days post-induction of colitis,the histological features and MPO activity returned to normal.The rats at 7 days post-induction of colitis showed hypersensitive response to rectal distension without an accompaning change in rectal compliance,and defecated more stools than control animals when under stress.CONCLUSION: These results concur largely with the characteristic features of IBS, visceral hypersensitivity and altered defecation pattern in the absence of detectable disease, suggesting that this animal model is a methodologically convenient and useful model for studying a subset of IBS.展开更多
ChatG PT,an artificial intelligence generated content (AIGC) model developed by OpenAI,has attracted worldwide attention for its capability of dealing with challenging language understanding and generation tasks in th...ChatG PT,an artificial intelligence generated content (AIGC) model developed by OpenAI,has attracted worldwide attention for its capability of dealing with challenging language understanding and generation tasks in the form of conversations.This paper briefly provides an overview on the history,status quo and potential future development of ChatGPT,helping to provide an entry point to think about ChatGPT.Specifically,from the limited open-accessed resources,we conclude the core techniques of ChatGPT,mainly including large-scale language models,in-context learning,reinforcement learning from human feedback and the key technical steps for developing ChatGPT.We further analyze the pros and cons of ChatGPT and we rethink the duality of ChatGPT in various fields.Although it has been widely acknowledged that ChatGPT brings plenty of opportunities for various fields,mankind should still treat and use ChatG PT properly to avoid the potential threat,e.g.,academic integrity and safety challenge.Finally,we discuss several open problems as the potential development of ChatGPT.展开更多
The seed germination and seedling growth of pakchoi （Brassica campestris ssp. chinensis var. communis Tsen et Lee cv. Hanxiao） were not significantly inhibited until the concentration of NaCl was increased to 150 mm...The seed germination and seedling growth of pakchoi （Brassica campestris ssp. chinensis var. communis Tsen et Lee cv. Hanxiao） were not significantly inhibited until the concentration of NaCl was increased to 150 mmol/L. Treatment of pakchoi seeds with exogenous 5-aminolevulinic acid （ALA）, at concentrations ranging from 0.01 to 10.00 mg/L, promoted seed germination when seeds were stressed by salinity, whereas levulinic acid （LA）, an inhibitor of ALA dehydrase, significantly inhibited seed germination and seedling growth, suggesting that metabolism of ALA into porphyrin compounds was necessary for seed germination and seedling growth. Determination of respiratory rate during seed germination showed that ALA increased seed respiration under both normal conditions and salt stress. Furthermore, salt stress decreased levels of endogenous ALA, as well as heme, in etiolated seedlings. More salt-tolerant cultivars of pakchoi contained higher relative levels of endogenous ALA and heme under conditions of salt stress. These results indicate that salt stress may inhibit the biosynthesis of endogenous ALA and then heme, which is necessary for seed germination, and treatment of seeds with exogenous ALA prior to germination may be associated with the biosynthesis of heme.展开更多
With high energy density and low material cost,lithium sulfur batteries(LSBs)emerge quite expeditiously as a fascinating energy storage system over the past decade.Broad applications of LSBs ranging from electric vehi...With high energy density and low material cost,lithium sulfur batteries(LSBs)emerge quite expeditiously as a fascinating energy storage system over the past decade.Broad applications of LSBs ranging from electric vehicles to stationary grid storage seem rather bright in recent literatures.However,there still exist many pressing challenges to be addressed because we do not yet fully understand and control the electrode-electrolyte interface chemistries during battery operation,such as polysulide shuttling and poor utilization of active sulfur.Single-atom catalysts(SACs)pave new possibilities of tackling the tough issues due to their decent applicability in the atomic-level identification of structure-activity relationships and reaction mechanism,as well as their structural tunability with atomic precision.This review comprehensively summarizes the very recent advances in utilization of highly active SACs for LSBs by stating and discussing the related publications,which involves catalyst synthesis routes,battery pertormance,catalytic mechanisms,optimization strategies,and promises to achieve long-lite,high-energy LSBs.We see that endeavors to employ SACs to modify sulfur cathode have allowed efficient polysulfide conversion and confinement,leading to the minimization of shuttle effect.Parallel efforts are being devoted to extending the scope of SACs to cell separator and lithium metal anode in order to unlock the full potential of LSBs.We also obtain mechanistic insights into battery chemistries and nature of SACs in their strong interactions with polysulfides through advanced in situ characterizations documented.Overall,acceleration in the development of LSBs by introducing SACs is noticeable,and this cutting edge needs more attentions to further promoting the design of better LSBs.展开更多
Bone Morphogenetic Proteins(BMPs)are a group of signaling molecules that belongs to the Transforming Growth Factor-b(TGF-b)superfamily of proteins.Initially discovered for their ability to induce bone formation,BMPs a...Bone Morphogenetic Proteins(BMPs)are a group of signaling molecules that belongs to the Transforming Growth Factor-b(TGF-b)superfamily of proteins.Initially discovered for their ability to induce bone formation,BMPs are now known to play crucial roles in all organ systems.BMPs are important in embryogenesis and development,and also in maintenance of adult tissue homeostasis.Mouse knockout models of various components of the BMP signaling pathway result in embryonic lethality or marked defects,highlighting the essential functions of BMPs.In this review,we first outline the basic aspects of BMP signaling and then focus on genetically manipulated mouse knockout models that have helped elucidate the role of BMPs in development.A significant portion of this review is devoted to the prominent human pathologies associated with dysregulated BMP signaling.展开更多
To survive under cold temperatures plants must be able to perceive a cold signal and transduce it into downstream components that induce appropriate defense mechanisms. In addition to inducing adaptive defenses, such ...To survive under cold temperatures plants must be able to perceive a cold signal and transduce it into downstream components that induce appropriate defense mechanisms. In addition to inducing adaptive defenses, such as the production of osmotic factors to prevent freezing and the reprogramming of transcriptional pathways, cold temperatures induce changes in plant growth and development which can affect the plant life cycle. In this review, we summarize recent progress in characterizing cold-related genes and the pathways that allow transduction of the cold signal in plants, focusing primarily on studies in Arabidopsis tbaliana and rice （Oryza sativa）. We summarize cold perception and signal transduction from the plasma membrane to the nucleus, which involves cold sensors, calcium signals, calciumbinding proteins, mitogen-activated protein kinase cascades, and the C-repeat binding factor/dehydrationresponsive element binding pathways, as well as trehalose metabolism. Finally, we describe the balance between plant organogenesis and cold tolerance mechanisms in rice. This review encapsulates the known cold signaling factors in plants and provides perspectives for ongoing cold signaling research.展开更多
Field trials were performed to evaluate various techniques for measuring spray deposition and aerial drift during spray application to paddy field.The application of a spraying agent containing the fluorescent dye Rho...Field trials were performed to evaluate various techniques for measuring spray deposition and aerial drift during spray application to paddy field.The application of a spraying agent containing the fluorescent dye Rhodamine-B was applied by an unmanned aerial vehicle(UAV)which flew at a height of 5 m,a speed of 3 m/s,and the wind speed of 3 m/s.The results showed that because the downdraft produced by a helicopter rotor increased the penetrability of crops,there is a higher deposition on the upper layer and the under layer than the traditional spraying.The average deposition on the upper layer accounts for 28% of the total spraying,the deposition on the under layer accounts for 26% of the total spraying.The deposition on the under layer takes up 92.8% of the deposition on the upper layer.Droplets drift data showed that the drift of non-target area took up 12.9% of the total liquid spray.The 90% drifting droplets were located within a range of 8 m of the target area;the drift quantity was almost zero at a distance of 50 m away from the treated area.展开更多
Land use reflects human activities on land.Urban land use is the highest level human alteration on Earth,and it is rapidly changing due to population increase and urbanization.Urban areas have widespread effects on lo...Land use reflects human activities on land.Urban land use is the highest level human alteration on Earth,and it is rapidly changing due to population increase and urbanization.Urban areas have widespread effects on local hydrology,climate,biodiversity,and food production[1,2].However,maps,that contain knowledge on the distribution,pattern and composition of various land use types in urban areas,are limited to city level.The mapping standard on data sources,methods,land use classification schemes varies from city to city,due to differences in financial input and skills of mapping personnel.To address various national and global environmental challenges caused by urbanization,it is important to have urban land uses at the national and global scales that are derived from the same or consistent data sources with the same or compatible classification systems and mapping methods.This is because,only with urban land use maps produced with similar criteria,consistent environmental policies can be made,and action efforts can be compared and assessed for large scale environmental administration.However,despite of the fact that a number of urban-extent maps exist at global scales[3,4],more detailed urban land use maps do not exist at the same scale.Even at big country or regional levels such as for the United States,China and European Union,consistent land use mapping efforts are rare[5,6](e.g.,https://sdi4apps.eu/open_land_use/).展开更多
Enhancing the terrestrial ecosystem carbon sink(referred to as terrestrial C sink) is an important way to slow down the continuous increase in atmospheric carbon dioxide(CO_(2)) concentration and to achieve carbon neu...Enhancing the terrestrial ecosystem carbon sink(referred to as terrestrial C sink) is an important way to slow down the continuous increase in atmospheric carbon dioxide(CO_(2)) concentration and to achieve carbon neutrality target.To better understand the characteristics of terrestrial C sinks and their contribution to carbon neutrality,this review summarizes major progress in terrestrial C budget researches during the past decades,clarifies spatial patterns and drivers of terrestrial C sources and sinks in China and around the world,and examines the role of terrestrial C sinks in achieving carbon neutrality target.According to recent studies,the global terrestrial C sink has been increasing from a source of (-0.2±0.9) Pg C yr^(-1)(1 Pg=1015g)in the 1960s to a sink of (1.9±1.1) Pg C yr^(-1) in the 2010s.By synthesizing the published data,we estimate terrestrial C sink of 0.20–0.25 Pg C yr^(-1) in China during the past decades,and predict it to be 0.15–0.52 Pg C yr^(-1) by 2060.The terrestrial C sinks are mainly located in the mid-and high latitudes of the Northern Hemisphere,while tropical regions act as a weak C sink or source.The C balance differs much among ecosystem types:forest is the major C sink;shrubland,wetland and farmland soil act as C sinks;and whether the grassland functions as C sink or source remains unclear.Desert might be a C sink,but the magnitude and the associated mechanisms are still controversial.Elevated atmospheric CO_(2) concentration,nitrogen deposition,climate change,and land cover change are the main drivers of terrestrial C sinks,while other factors such as fires and aerosols would also affect ecosystem C balance.The driving factors of terrestrial C sink differ among regions.Elevated CO_(2) concentration and climate change are major drivers of the C sinks in North America and Europe,while afforestation and ecological restoration are additionally important forcing factors of terrestrial C sinks in China.For future studies,we recommend the necessity for intensive and long-term ec展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos. 31271795 and 31200273)
文摘Transcription activator-like effector nucleases （TALENs） and clustered regularly interspaced short palindromic repeats （CRISPR）/ CRISPR-associated （Cas） systems have emerged as powerful tools for genome editing in a variety of species. Here, we report, for the first time, targeted mutagenesis in Zea mays using TALENs and the CRISPR/Cas system. We designed five TALENs targeting 4 genes, namely ZmPDS, ZmlPKIA, ZmlPK, ZmMRP4, and obtained targeting efficiencies of up to 23.1% in protoplasts, and about 13.3% to 39.1% of the transgenic plants were somatic mutations. Also, we constructed two gRNAs targeting the ZmlPK gene in maize protoplasts, at frequencies of 16.4% and 19.1%, respectively. In addition, the CRISPR/Cas system induced targeted mutations in Z. mays protoplasts with efficiencies （13.1%） similar to those obtained with TALENs （9.1%）. Our results show that both TALENs and the CRISPR/Cas system can be used for genome modification in maize.
文摘The importance of cancer stem cells （CSCs） in tumor-initiation has been firmly established in leukemia and recently reported for a variety of solid tumors. However, the role of CSCs in multistage cancer progression, particularly with respect to metastasis, has not been well-defined. Cancer metastasis requires the seeding and successful colonization of specialized CSCs at distant organs. The biology of normal stem cells and CSCs share remarkable similarities and may have important implications when applied to the study of cancer metastasis. Furthermore, overlapping sets of molecules and pathways have recently been identified to regulate both stem cell migration and cancer metastasis. These molecules constitute a complex network of cellular interactions that facilitate both the initiation of the pre-metastasis niche by the primary tumor and the formation of a nurturing organ microenvironment for migrating CSCs. In this review, we surveyed the recent advances in this dynamic field and propose a unified model of cancer progression in which CSCs assume a central role in both tumorigenesis and metastasis. Better understanding of CSCs as a fundamental component of the metastatic cascade will lead to novel therapeutic strategies against metastatic cancer.
基金This work was supported in part by the National Science Fund for Distinguished Young Scholars in China under grant 61425012the National Science Foundation Project in China under grant 61931005 and 61731017.
文摘Mobile communication standards have been developed into a new era of B5G and 6G.In recent years,low earth orbit(LEO)satellites and space Internet have become hot topics.The integrated satellite and terrestrial systems have been widely discussed by industries and academics,and even are expected to be applied in those huge constellations in construction.This paper points out the trends of two stages towards system integration of the terrestrial mobile communication and the satellite communications:to be compatible with 5G,and to be integrated within 6G.Based on analysis of the challenges of both stages,key technologies are thereafter analyzed in detail,covering both air interface currently discussed in 3GPP for B5G and also novel network architecture and related transmission technologies toward future 6G.
基金This study was funded by Natural Science Foundation of Liaoning Province of China(2013021017).
文摘Background:The prevalence of Mycoplasma pneumoniae pneumonia has increased considerably in recent years.To evaluate the efficacy of combined treatment of azithromycin with intravenous immunoglo-bulin (IVIG) or methylprednisolone in children with refractory Mycoplasma pneumoniae pneumonia (RMPP).Methods:Children with RMPP were randomly allocated to group A [intravenous azithromycin (IA)+ methylprednisolone],group B (IA+IVIG) or group C (IA alone).Following a 7-day treatment,group C patients were randomly separated into two sub-groups:group C1 (IA+methylprednisolone) and group C2 (IA+IVIG).Temperature,respiratory symptoms and signs were examined.The average febrile period after treatment (F2),average total febrile period (F3),infiltration absorption,atelectasis resolution,pleural effusion disappearance were determined.The levels of C-reactive protein (CRP),D-dimer,and lactate dehydrogenase (LDH) were measured.Results:Seven days after enrollment,the average F2 after treatment of group A was the shortest.Compared with the control group C,the combined treatment group A and B showed higher rates of infiltration absorption,atelectasis resolution and pleural effusion disappearance,while lower levels of serum CRP,D-dimer and LDH.Fourteen days after enrollment,all children with combined therapy clinically improved,and presented better laboratory results.Group C1 showed shorter F3 and lower levels of CRP and LDH than those of group C2.Overall,group A showed the shortest F3,also has the lowest CRP and LDH.Conclusions:Azithromycin with IVIG or methylprednisolone was better treatment for children with RMPP than azithromycin alone.IVIG treatment may be beneficial,especially when the efficacy of corticosteroids is insecure,thus could be considered as an alternative of primary therapeutic approaches.
文摘AIM:To evaluate the efficacy of simple and extended cholecystectomy for mucosa(T1a) or muscularis(T1b) gallbladder(GB) cancer. METHODS:Original studies on simple and extended cholecystectomy for T1a or T1b GB cancer were searched from MEDLINE(PubMed) ,Cochrane Library,EMBase,and CancerLit using the search terms of GB,cancer/carcinoma/tumor/neoplasm. RESULTS:Twenty-nine out of the 2312 potentially relevant publications met the eligibility criteria.Of the 1266 patients with GB cancer included in the publications,706(55.8%) and 560(44.2%) had T1a and T1b GB cancer,respectively.Simple cholecystectomy for T1a and T1b GB cancer was performed in 590(83.6%) and 375(67.0%) patients,respectively(P<0.01) .In most series,the treatment of choice was simple cholecystectomy for T1a GB cancer patients with a 5-year survival rate of 100%.Lymph node metastasis was detected in 10.9% of the T1b GB cancer patients and in 1.8%of the T1a GB cancer patients,respectively(P<0.01) .Eight patients(1.1%) with T1a GB cancer and 52 patients(9.3%) with T1b GB cancer died of recurrent GB cancer(P<0.01) . CONCLUSION:Simple cholecystectomy represents the adequate treatment of T1a GB cancer.There is no definite evidence that extended cholecystectomy is advantageous over simple cholecystectomy for T1b GB cancer.
文摘Grain size determines grain weight and affects grain quality. Several major quantitative trait loci （QTLs） regulating grain size have been cloned; however, our understanding of the underlying mechanism that regulates the size of rice grains remains fragmentary. Here, we report the cloning and characterization of a dominant QTL, GRAIN SIZE ON CHROMOSOME 2 （GS2）, which encodes Growth-Regulating Factor 4 （OsGRF4）, a transcriptional regulator. GS2 localizes to the nucleus and may act as a transcription activator. A rare mutation of GS2 affecting the binding site of a microRNA, OsmiR396c, causes elevated expression of GS2/OsGRF4. The increase in GS2 expression leads to larger cells and increased numbers of cells, which thus enhances grain weight and yield. The introduction of this rare allele of GS2/OsGRF4 into rice cultivars could significantly enhance grain weight and increase grain yield, with possible applications in breeding high-yield rice varieties.
基金Acknowledgment This research was supported by grants from the Ministry of Science and Technology of China （2006CB943901, 2007CB948003） the National Natural Science Foundation of China （30600306, 30623003） Shanghai Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences （2007KIP 101,2007KIP401）, Chinese Academy of Sciences.
文摘Dear Editor, Human embryonic stem （ES） cells possess the potential to differentiate into all the cell types of the human body and provide potential applications in regenerative medicine . However, the concerns of immune rejection hamper transplantation therapies using human ES cells. To avoid the complications of immune rejection, diverse methods, such as somatic nuclear transfer （also called therapeutic cloning） and fusion of somatic ceils with human ES ceils , have been attempted to produce patient-specific pluripotent stem cells. Most of these approaches have resulted in little success. The generation of human iPS cells （induced
文摘Thick and ultra-thick coal seams are main coal seams for high production rate and high efficiency in Chinese coal mines, which accounts for 44 % of the total minable coal reserve. A fully mechanized top-coal caving mining method is a main underground coal extraction method for ultra-thick coal seams. The coal extraction technologies for coal seams less than 14 m thick were extensively used in China. However, for coal seams with thickness greater than 14 m, there have been no reported cases in the world for underground mechanical extraction with safe performance, high efficiency and high coal recovery ratio. To deal with this case, China Coal Technology ＆ Engineering Group, Datong Coal Mine Group, and other 15 organizations in China launched a fundamental and big project to develop coal mining technologies and equipment for coal seams with thicknesses greater than 14 m. After the completion of the project, a coal extraction method was developed for top-coal caving with a large mining height, as well as a ground control theory for ultra-thick coal seams. In addition, the mining technology for top-coal caving with a large mining height, the ground support technology for roadway in coal seams with a large cross-section, and the prevention and control technology for gas and fire hazards were developed and applied. Furthermore, a hydraulic support with a mining height of 5.2 m, a shearer with high reliability, and auxiliary equipment were developed and manufactured. Practical implication on the technologies and equipment developed was successfully completed at the No. 8105 coal face in the Tashan coal mine, Datong, China. The major achievements of the project are summarized as follows： 1. A top-coal caving method for ultra-thick coal seams is proposed with a cutting height of 5 m and a top-coal caving height of 15 m. A structural mechanical model of overlying strata called cantilever beam-articulated rock beam is established. Based on the model, the load resistance of the hydraulic support with a large mining heigh
基金the Research Institute of Veterinary Science,College of Veterinary Medieine,Seoul National University
文摘AIM:Irritable bowel syndrome(IBS)is a functional bowel disorder characterized by visceral hypersensitivity and altered bowel motility.There is increasing evidence suggesting the role of inflammation in the pathogenesis of IBS,which addresses the possibility that formerly established rat model of colitis could be used as an IBS model after the inflammation subsided. METHODS:Colitis was induced by intracolonic instillation of 4% acetic acid in male Sprague-Dawley rats.The extent of inflammation was assessed by histological examination and myeloperoxidase(MPO)activity assay.After subsidence of colitis,the rats were subjected to rectal distension and restraint stress,then the abdominal withdrawal reflex and the number of stress-induced fecal output were measured, respectively. RESULTS:At 2 days post-induction of colitis,the colon showed characteristic inflammatory changes in histology and 8-fold increase in MPO activity.At 7 days post-induction of colitis,the histological features and MPO activity returned to normal.The rats at 7 days post-induction of colitis showed hypersensitive response to rectal distension without an accompaning change in rectal compliance,and defecated more stools than control animals when under stress.CONCLUSION: These results concur largely with the characteristic features of IBS, visceral hypersensitivity and altered defecation pattern in the absence of detectable disease, suggesting that this animal model is a methodologically convenient and useful model for studying a subset of IBS.
基金supported by National Key Research and Development Program of China (2021YFB1714300)National Natural Science Foundation of China (62293502, 61831022, 61976211)Youth Innovation Promotion Association CAS。
文摘ChatG PT,an artificial intelligence generated content (AIGC) model developed by OpenAI,has attracted worldwide attention for its capability of dealing with challenging language understanding and generation tasks in the form of conversations.This paper briefly provides an overview on the history,status quo and potential future development of ChatGPT,helping to provide an entry point to think about ChatGPT.Specifically,from the limited open-accessed resources,we conclude the core techniques of ChatGPT,mainly including large-scale language models,in-context learning,reinforcement learning from human feedback and the key technical steps for developing ChatGPT.We further analyze the pros and cons of ChatGPT and we rethink the duality of ChatGPT in various fields.Although it has been widely acknowledged that ChatGPT brings plenty of opportunities for various fields,mankind should still treat and use ChatG PT properly to avoid the potential threat,e.g.,academic integrity and safety challenge.Finally,we discuss several open problems as the potential development of ChatGPT.
基金the Overseas Scholarship Foundation of the Chinese Education Department，国家自然科学基金
文摘The seed germination and seedling growth of pakchoi （Brassica campestris ssp. chinensis var. communis Tsen et Lee cv. Hanxiao） were not significantly inhibited until the concentration of NaCl was increased to 150 mmol/L. Treatment of pakchoi seeds with exogenous 5-aminolevulinic acid （ALA）, at concentrations ranging from 0.01 to 10.00 mg/L, promoted seed germination when seeds were stressed by salinity, whereas levulinic acid （LA）, an inhibitor of ALA dehydrase, significantly inhibited seed germination and seedling growth, suggesting that metabolism of ALA into porphyrin compounds was necessary for seed germination and seedling growth. Determination of respiratory rate during seed germination showed that ALA increased seed respiration under both normal conditions and salt stress. Furthermore, salt stress decreased levels of endogenous ALA, as well as heme, in etiolated seedlings. More salt-tolerant cultivars of pakchoi contained higher relative levels of endogenous ALA and heme under conditions of salt stress. These results indicate that salt stress may inhibit the biosynthesis of endogenous ALA and then heme, which is necessary for seed germination, and treatment of seeds with exogenous ALA prior to germination may be associated with the biosynthesis of heme.
基金the National Key R&D Program of China(No.2018YFA0702003)the National Natural Science Foundation of China(Nos.21890383,21671117,21871159)+1 种基金the China Postdoctoral Science Foundation(No.2019M660607)Z.C.Z.acknowledges support from the Shuimu Isinghua Scholar Program.
文摘With high energy density and low material cost,lithium sulfur batteries(LSBs)emerge quite expeditiously as a fascinating energy storage system over the past decade.Broad applications of LSBs ranging from electric vehicles to stationary grid storage seem rather bright in recent literatures.However,there still exist many pressing challenges to be addressed because we do not yet fully understand and control the electrode-electrolyte interface chemistries during battery operation,such as polysulide shuttling and poor utilization of active sulfur.Single-atom catalysts(SACs)pave new possibilities of tackling the tough issues due to their decent applicability in the atomic-level identification of structure-activity relationships and reaction mechanism,as well as their structural tunability with atomic precision.This review comprehensively summarizes the very recent advances in utilization of highly active SACs for LSBs by stating and discussing the related publications,which involves catalyst synthesis routes,battery pertormance,catalytic mechanisms,optimization strategies,and promises to achieve long-lite,high-energy LSBs.We see that endeavors to employ SACs to modify sulfur cathode have allowed efficient polysulfide conversion and confinement,leading to the minimization of shuttle effect.Parallel efforts are being devoted to extending the scope of SACs to cell separator and lithium metal anode in order to unlock the full potential of LSBs.We also obtain mechanistic insights into battery chemistries and nature of SACs in their strong interactions with polysulfides through advanced in situ characterizations documented.Overall,acceleration in the development of LSBs by introducing SACs is noticeable,and this cutting edge needs more attentions to further promoting the design of better LSBs.
基金The reported work was in part supported by research grants from the National Institutes of Health(AR50142 and AR054381 to RCH and HHL)RW,JG,and OI were recipients of the Pritzker Summer Research Fellowship funded through a NIH T-35 training grant(NIDDK).AH was a recipient of the Urban Leadership Fellowship from Miami University.
文摘Bone Morphogenetic Proteins(BMPs)are a group of signaling molecules that belongs to the Transforming Growth Factor-b(TGF-b)superfamily of proteins.Initially discovered for their ability to induce bone formation,BMPs are now known to play crucial roles in all organ systems.BMPs are important in embryogenesis and development,and also in maintenance of adult tissue homeostasis.Mouse knockout models of various components of the BMP signaling pathway result in embryonic lethality or marked defects,highlighting the essential functions of BMPs.In this review,we first outline the basic aspects of BMP signaling and then focus on genetically manipulated mouse knockout models that have helped elucidate the role of BMPs in development.A significant portion of this review is devoted to the prominent human pathologies associated with dysregulated BMP signaling.
基金supported by the Strategic Priority Research Programs A of Chinese Academy of Sciences(XDA08010205)the Basic Science Center Project of National Natural Science Foundation of China(31788103)
文摘To survive under cold temperatures plants must be able to perceive a cold signal and transduce it into downstream components that induce appropriate defense mechanisms. In addition to inducing adaptive defenses, such as the production of osmotic factors to prevent freezing and the reprogramming of transcriptional pathways, cold temperatures induce changes in plant growth and development which can affect the plant life cycle. In this review, we summarize recent progress in characterizing cold-related genes and the pathways that allow transduction of the cold signal in plants, focusing primarily on studies in Arabidopsis tbaliana and rice （Oryza sativa）. We summarize cold perception and signal transduction from the plasma membrane to the nucleus, which involves cold sensors, calcium signals, calciumbinding proteins, mitogen-activated protein kinase cascades, and the C-repeat binding factor/dehydrationresponsive element binding pathways, as well as trehalose metabolism. Finally, we describe the balance between plant organogenesis and cold tolerance mechanisms in rice. This review encapsulates the known cold signaling factors in plants and provides perspectives for ongoing cold signaling research.
基金Special Fund for Agro-scientific Research in the Public Interest(201203025)by Ministry of Agriculture,Chinathe National High Technology Research and Development Program of China(SS2013AA100303).
文摘Field trials were performed to evaluate various techniques for measuring spray deposition and aerial drift during spray application to paddy field.The application of a spraying agent containing the fluorescent dye Rhodamine-B was applied by an unmanned aerial vehicle(UAV)which flew at a height of 5 m,a speed of 3 m/s,and the wind speed of 3 m/s.The results showed that because the downdraft produced by a helicopter rotor increased the penetrability of crops,there is a higher deposition on the upper layer and the under layer than the traditional spraying.The average deposition on the upper layer accounts for 28% of the total spraying,the deposition on the under layer accounts for 26% of the total spraying.The deposition on the under layer takes up 92.8% of the deposition on the upper layer.Droplets drift data showed that the drift of non-target area took up 12.9% of the total liquid spray.The 90% drifting droplets were located within a range of 8 m of the target area;the drift quantity was almost zero at a distance of 50 m away from the treated area.
基金partially supported by the National Key Research and Development Program of China(2016YFA0600104)supported by donations made by Delos Living LLC,and the Cyrus Tang Foundation+2 种基金supported by the National Natural Science Foundation of China(41471419)Beijing Institute of Urban Planningsupported by the Fundamental Research Funds for the Central Universities(CCNU19TD002).
文摘Land use reflects human activities on land.Urban land use is the highest level human alteration on Earth,and it is rapidly changing due to population increase and urbanization.Urban areas have widespread effects on local hydrology,climate,biodiversity,and food production[1,2].However,maps,that contain knowledge on the distribution,pattern and composition of various land use types in urban areas,are limited to city level.The mapping standard on data sources,methods,land use classification schemes varies from city to city,due to differences in financial input and skills of mapping personnel.To address various national and global environmental challenges caused by urbanization,it is important to have urban land uses at the national and global scales that are derived from the same or consistent data sources with the same or compatible classification systems and mapping methods.This is because,only with urban land use maps produced with similar criteria,consistent environmental policies can be made,and action efforts can be compared and assessed for large scale environmental administration.However,despite of the fact that a number of urban-extent maps exist at global scales[3,4],more detailed urban land use maps do not exist at the same scale.Even at big country or regional levels such as for the United States,China and European Union,consistent land use mapping efforts are rare[5,6](e.g.,https://sdi4apps.eu/open_land_use/).
基金supported by the National Natural Science Foundation of China (31988102)。
文摘Enhancing the terrestrial ecosystem carbon sink(referred to as terrestrial C sink) is an important way to slow down the continuous increase in atmospheric carbon dioxide(CO_(2)) concentration and to achieve carbon neutrality target.To better understand the characteristics of terrestrial C sinks and their contribution to carbon neutrality,this review summarizes major progress in terrestrial C budget researches during the past decades,clarifies spatial patterns and drivers of terrestrial C sources and sinks in China and around the world,and examines the role of terrestrial C sinks in achieving carbon neutrality target.According to recent studies,the global terrestrial C sink has been increasing from a source of (-0.2±0.9) Pg C yr^(-1)(1 Pg=1015g)in the 1960s to a sink of (1.9±1.1) Pg C yr^(-1) in the 2010s.By synthesizing the published data,we estimate terrestrial C sink of 0.20–0.25 Pg C yr^(-1) in China during the past decades,and predict it to be 0.15–0.52 Pg C yr^(-1) by 2060.The terrestrial C sinks are mainly located in the mid-and high latitudes of the Northern Hemisphere,while tropical regions act as a weak C sink or source.The C balance differs much among ecosystem types:forest is the major C sink;shrubland,wetland and farmland soil act as C sinks;and whether the grassland functions as C sink or source remains unclear.Desert might be a C sink,but the magnitude and the associated mechanisms are still controversial.Elevated atmospheric CO_(2) concentration,nitrogen deposition,climate change,and land cover change are the main drivers of terrestrial C sinks,while other factors such as fires and aerosols would also affect ecosystem C balance.The driving factors of terrestrial C sink differ among regions.Elevated CO_(2) concentration and climate change are major drivers of the C sinks in North America and Europe,while afforestation and ecological restoration are additionally important forcing factors of terrestrial C sinks in China.For future studies,we recommend the necessity for intensive and long-term ec
