The repair and regeneration of bone defects are highly challenging orthopedic problems.Recently,Mg-based implants have gained popularity due to their unique biodegradation and elastic modulus similar to that of human ...The repair and regeneration of bone defects are highly challenging orthopedic problems.Recently,Mg-based implants have gained popularity due to their unique biodegradation and elastic modulus similar to that of human bone.The aim of our study is to develop a magnesium alloy with a controllable degradation that can closely match bone tissue to help injuries heal in vivo and avoid cytotoxicity caused by a sudden increase in ion concentration.In this study,we prepared and modified Mg-3Zn,Mg-3Zn-1Y,and Mg-2Zn-1Mn by hot extrusion,and used Mg-2.5Y-2.5Nd was as a control.We then investigated the effect of additions of Y and Mn on alloys'properties.Our results show that Mn and Y can improve not only compression strength but also corrosion resistance.The alloy Mg-2Zn-1Mn demonstrated good cytocompatibility in vitro,and for this reason we selected it for implantation in vivo.The degraded Mg-2Zn-1Mn implanted a bone defect area did not cause obvious rejection and inflammatory reaction,and the degradation products left no signs of damage to the heart,liver,kidney,or brain.Furthermore,we find that Mg-2Zn-1Mn can promote an osteoinductive response in vivo and the formation of bone regeneration.展开更多
The introduction of alleles into commercial crop breeding pipelines is both time consuming and costly.Two technologies that are disrupting traditional breeding processes are doubled haploid(DH)breeding and genome edit...The introduction of alleles into commercial crop breeding pipelines is both time consuming and costly.Two technologies that are disrupting traditional breeding processes are doubled haploid(DH)breeding and genome editing(GE).Recently,these techniques were combined into a GE trait delivery system called HI-Edit(Haploid Inducer-Edit).In HI-Edit,the pollen of a haploid inducer line is reprogrammed to deliver GE traits to any variety,obviating recurrent selection.For HI-Edit to operate at scale,an efficient transformable HI line is needed,but most maize varieties are recalcitrant to transformation,and haploid inducers are especially difficult to transform given their aberrant reproductive behaviors.Leveraging marker assisted selection and a three-tiered testing scheme,we report the development of new Iodent and Stiff Stalk maize germplasm that are transformable,have high haploid induction rates,and exhibit a robust,genetically-dominant anthocyanin native trait that may be used for rapid haploid identification.We show that transformation of these elite‘‘HI-Edit”lines is enhanced using the BABYBOOM and WUSCHEL morphogenetic factors.Finally,we evaluate the HI-Edit performance of one of the lines against both Stiff Stalk and non-Stiff Stalk testers.The strategy and results of this study should facilitate the development of commercially scalable HI-Edit systems in diverse crops.展开更多
The evolution of the microstructure and tensile rupture mechanism of laser welds in UNS N10003 alloy exposed to 700℃are investigated.Fine M_(6)C carbides precipitate around the primary eutectic M_(6)C-carbides in the...The evolution of the microstructure and tensile rupture mechanism of laser welds in UNS N10003 alloy exposed to 700℃are investigated.Fine M_(6)C carbides precipitate around the primary eutectic M_(6)C-carbides in the fusion zone after 100 h of exposure.During long-term thermal exposure,the size of the fine M_(6)C carbides increased.The eutectic M_(6)C-carbides in the as-welded fusion zone transformed into spherical M_(6)C carbides as the exposure time extends to 10000 h.Additionally,the spherical M_(6)C particles exhibit size coarsening with increasing exposure time.The tensile properties of the welded joints are not adversely affected by the evolution of eutectic M_(6)C-carbides and the coarsening of M_(6)C carbides.展开更多
Water table configuration gives rise to hierarchically nested groundwater flow systems.However,there remains a lack of comprehensive understanding regarding the controlling factors of water table and its impact on flo...Water table configuration gives rise to hierarchically nested groundwater flow systems.However,there remains a lack of comprehensive understanding regarding the controlling factors of water table and its impact on flow systems.Moreover,it remains challenging to identify characteristics of water table space variation through limited groundwater observations at the regional scale.Based on two ideal two-dimensional cross-section analytical models,this study presents a simplified approach to preliminarily assess the nonlinear interactions between water table variation and three driving factors:Topography,geol-ogy and climate.Two criteria,C1 and C2,are utilized to address issues at different scales ranging from basin to local:(i)the influence of various factors on water table configuration;and(ii)the influence of water table on groundwater flow pattern.Then,the Ordos Plateau is taken as an example to explore the role of the water table in nested groundwater systems using the provided approach and criterion.The applica-tion of this approach in the Ordos Plateau demonstrates its appropriateness as a practical method for prelim-inarily determining the characteristics of water table configuration and its impact on flow systems.The study explores the mechanism influencing spatial variation in the water table and improves understanding of the interaction between topography,geology,and climate on groundwater flow patterns.展开更多
BACKGROUND Gastric cancer(GC)is one of the most common cancers and has a poor prognosis.Treatment of GC has remained unchanged over the past few years.AIM To investigate the potential therapeutic targets and related r...BACKGROUND Gastric cancer(GC)is one of the most common cancers and has a poor prognosis.Treatment of GC has remained unchanged over the past few years.AIM To investigate the potential therapeutic targets and related regulatory biomarkers of GC.METHODS We obtained the public GC transcriptome sequencing dataset from the Gene Expression Omnibus database.The datasets contained 348 GC tissues and 141 healthy tissues.In total,251 differentially expressed genes(DEGs)were identified,including 187 down-regulated genes and 64 up-regulated genes.The DEGs’enriched functions and pathways include Progesterone-mediated oocyte maturation,cell cycle,and oocyte meiosis,Hepatitis B,and the Hippo signaling pathway.Survival analysis showed that BUB1,MAD2L1,CCNA2,CCNB1,and BIRC5 may be associated with regulation of the cell cycle phase mitotic spindle checkpoint pathway.We selected 26 regulated genes with the aid of the protein-protein interaction network analyzed by Molecular Complex Detection.RESULTS We focused on three critical genes,which were highly expressed in GC,but negatively related to patient survival.Furthermore,we found that knockdown of Yu K et al.Biochemical analysis in GC WJCC https://www.wjgnet.com 5024 July 26,2023 Volume 11 Issue 21 BIRC5,TRIP13 or UBE2C significantly inhibited cell proliferation and induced cell apoptosis.In addition,knockdown of BIRC5,TRIP13 or UBE2C increased cellular sensitivity to cisplatin.CONCLUSION Our study identified significantly upregulated genes in GC with a poor prognosis using integrated bioinformatics methods.展开更多
A rotating pre-twisted and inclined cantilever beam model (RPICBM) with the flapwise-chordwise-axial-torsional coupling is established with the Hamilton principle and the finite element (FE) method. The effectiveness ...A rotating pre-twisted and inclined cantilever beam model (RPICBM) with the flapwise-chordwise-axial-torsional coupling is established with the Hamilton principle and the finite element (FE) method. The effectiveness of the model is verified via comparisons with the literatures and the FE models in ANSYS. The effects of the setting and pre-twisted angles on the dynamic responses of the RPICBM are analyzed. The results show that:(i) the increase in the setting or pre-twisted angle results in the increases in the first-order flapwise and torsional frequencies while the decrease in the first-order chordwise frequency under rotating conditions;(ii) a positive/negative setting angle leads to a positive/negative constant component, while a positive/negative pre-twisted angle leads to a negative/positive constant component;(iii) when the rotation speed is non-zero, the pre-twisted angle or non-zero setting angle will result in the coupled flapwise-chordwiseaxial- torsional vibration of the RPICBM under axial base excitation.展开更多
For high corrosion resistance and extensively modified biodegradable Mg-based alloys and composites for bone implants,a new Mgbased matrix model prepared by powder metallurgy is discussed and developed.In this researc...For high corrosion resistance and extensively modified biodegradable Mg-based alloys and composites for bone implants,a new Mgbased matrix model prepared by powder metallurgy is discussed and developed.In this research,Mg-5 wt.%Zn alloys were selected as a case.And they were impacted by hot extrusion and aging treatments to construct microstructure with different characteristics.Their selfforming corrosion product layer in Ringer’s solution,biodegradable behavior and corrosion mechanism were minutely investigated by in vitro degradation,electrochemical corrosion and cytocompatibility.The results demonstrated the extruded Mg-5 wt.%Zn alloy aged for 96 h showed high corrosion resistance,good biocompatibility for L929 and excellent ability of maintaining sample integrity during the immersion.Significantly,the alloy showed fine-grain microstructure and uniform distributed hundred nano-sized second phases,which promoted the formation of the uniform and smooth corrosion product layer at the beginning of immersion.The corrosion product layer was more stable in chloride containing aqueous solution and could be directly formed and repaired quickly,which effectively protected the matrix from further corrosion.In addition,an ideal model of Mg-based matrix for bone tissue engineering was tried to presume and propose by discussing the causal relationship between microstructure and bio-corrosion process.展开更多
Objective To describe a hybrid endovascular procedure for aorta repair with different kinds of bypass followed by concomitant placement of stent graft in the aorta. Methods From June 2007 to May 2008, 5 consecutive p...Objective To describe a hybrid endovascular procedure for aorta repair with different kinds of bypass followed by concomitant placement of stent graft in the aorta. Methods From June 2007 to May 2008, 5 consecutive patients who presented with aortic aneurysm or dissection were treated with a new hybrid aorta repair technique. Complete surgical rerouting of supra-aortic vessels was simultaneously created by endovascular repair of aortic arch aneurysm with stent graft. Hybrid left carotid-subclavian bypass with stent graft deployment covering the ostium of the left subclavian artery was performed in a Debakey type III aortic dissection case. The supra-aortic branch was revascularized in 2 cases from ascending aorta to bilateral common carotid arteries using a 16-8 mm bifurcated graft, then total aortic arch and descending artery was occluded with stent-graft. The left carotid artery to the left subclavian artery bypass was created in 1 case, followed by stent-graft deployment. Two cases of infrarenal abdominal aortic aneurysm underwent left external iliac artery to left internal iliac artery bypass by a retroperineal route, then hybrid procedure was performed with bifurcated stent-graft. All stent grafts were deployed via a retrograde femoral artery approach in 5 patients. Results Technical success with complete aneurysmal exclusion was achieved in all patients. There was no incidence of encloleak. During a follow-up period of 2 to 10 months, documented perioperative neurologic events did not occur in all patients. One patient suffered from adult respiratory distress syndrome. After received tracheostomy, he recovered later. There was one death resulting from a postoperative myocar- dial infarction. Conclusion Hybrid arch repair provides an alternative therapy to patients otherwise considered prohibitively high risk for traditional open arch and thoracoabdominal aorta repair.展开更多
Glaciers are crucial water resources for arid inland rivers in Northwest China.In recent decades,glaciers are largely experiencing shrinkage under the climate-warming scenario,thereby exerting tremendous influences on...Glaciers are crucial water resources for arid inland rivers in Northwest China.In recent decades,glaciers are largely experiencing shrinkage under the climate-warming scenario,thereby exerting tremendous influences on regional water resources.The primary role of understudying watershed scale glacier changes under changing climatic conditions is to ensure sustainable utilization of regional water resources,to prevent and mitigate glacier-related disasters.This study maps the current(2020)distribution of glacier boundaries across the Kaidu-Kongque river basin,south slope of Tianshan Mountains,and monitors the spatial evolution of glaciers over five time periods from 2000-2020 through thresholded band ratios approach,using 25 Landsat images at 30 m resolution.In addition,this study attempts to understand the role of climate characteristics for variable response of glacier area.The results show that the total area of glaciers was 398.21 km^(2)in 2020.The glaciers retreated by about 1.17 km^(2)/a(0.26%/a)from 2000 to 2020.The glaciers were reducing at a significantly rapid rate between 2000 and 2005,a slow rate from 2005 to 2015,and an accelerated rate during 2015-2020.The meteorological data shows slight increasing trends of mean annual temperature(0.02℃/a)and annual precipitation(2.07 mm/a).The correlation analysis demonstrates that the role of temperature presents more significant correlation with glacier recession than precipitation.There is a temporal hysteresis in the response of glacier change to climate change.Increasing trend of temperature in summer proves to be the driving force behind the Kaidu-Kongque basin glacier recession during the recent 20 years.展开更多
Objective To study the coronary microvascular function in older patients with heart failure with preserved ejection fraction (HFpEF) using an invasive pressure–temperature sensor guidewire. Methods Patients undergoin...Objective To study the coronary microvascular function in older patients with heart failure with preserved ejection fraction (HFpEF) using an invasive pressure–temperature sensor guidewire. Methods Patients undergoing echocardiography and cardiac catheterization examinations for exertional dyspnea and a positive stress test were retrospectively enrolled from January 2014 to November 2017, and were allocated into the control group or HFpEF group. The HFpEF group was secondary divided into two groups according to the age of 65 years. Comparing the clinical features and values obtained in examinations between the three groups, multivariate regression analysis was used to analyze the predictors of left ventricle end diastolic pressure (LVEDP). Results There were 87 patients enrolled in this study. The older HFpEF patients (n = 32) were more likely to be female;and had the most comorbidities, such as diabetes mellitus, atrial fibrillation, and chronic kidney dysfunction (CKD) with a low estimated glomerular filtration rate (eGFR), and had a similar hypertensive prevalence as the adult HFpEF group (n = 24), whose mean LVEDP and index of microcirculatory resistance (IMR) were highest in comparison to the adult HFpEF patients and controls (n = 31). The coronary flow reserve (CFR) in the older HFpEF and adult HFpEF groups was similarly reduced. In the regression analysis, the IMR linearly correlated to LVEDP, and was the only independent predictor of LVEDP. Conclusions An increased IMR and reduced CFR were characteristics of microvascular dysfunction in older HFpEF patients. The IMR independently had a positive linear correlation with LVEDP. Microvascular rarefaction might be a subsequent pathological progression in the development of HFpEF.展开更多
BACKGROUND Fulminant lupus myocarditis is a rare but fatal manifestation of systemic lupus erythematosus.Aggressive immunosuppressive treatments are important in its successful management.However,they can significantl...BACKGROUND Fulminant lupus myocarditis is a rare but fatal manifestation of systemic lupus erythematosus.Aggressive immunosuppressive treatments are important in its successful management.However,they can significantly damage the immunity and are associated with a considerable risk of infection development and spread.We present a rare and complicated case of a 20-year-old female diagnosed with fulminant lupus myocarditis accompanied by pneumonia.The patient was successfully treated with plasma exchange(PE)for fulminant lupus myocarditis.CASE SUMMARY A 20-year-old Chinese woman presented to the Hematology Department complaining of fatigue and knee pain.Blood test showed anemia and thrombocytopenia.On the second day of hospitalization,she was transferred to the ICU due to dyspnea and hypotension.Autoimmune profiles showed hypocomplementemia and positive antinuclear antibodies.Computer tomography showed an enlarged heart and pneumonia.Ultrasound revealed an enlarged heart with a low left ventricular ejection fraction.Fulminant lupus myocarditis with cardiogenic shock was initially considered.Due to the accompanying pneumonia,aggressive immunosuppression was contraindicated.Her cardiac function remained critical after the initial therapy of intravenous immunoglobulin and corticosteroids at a conventional dose,but she responded well to later PE therapy plus corticosteroids administration.The patient fully recovered with normal cardiac function.CONCLUSION This case indicates that PE is a valuable treatment choice without adverse effects of immunosuppression in patients with fulminant lupus myocarditis and coexisting infection.展开更多
Objective To investigate the application of the retroperitoneal approach in aortic surgery. Methods We collected and analyzed data of 7 patients in Macao who presented with aortic diseases from 2007 to 2008 and were t...Objective To investigate the application of the retroperitoneal approach in aortic surgery. Methods We collected and analyzed data of 7 patients in Macao who presented with aortic diseases from 2007 to 2008 and were treated with aorta repair through retroperitoneal approach. Demographic features as well as intraoperative and postoperative data were analyzed. One case of thoracoabdominal aneurysm and 4 cases of abdominal aneurysm received artificial graft, among which hybrid iliac artery reconstruction with Zenith stent covering the ostium of the left subclavian artery was performed in 2 cases of infrarenal abdominal aneurysm. Aortic-iliac artery bypass was performed in 2 cases of aortoiliac occlusion. Results No operative or early postoperative death was observed. No perioperative intestinal adhesion or ureteral obstruction was found. One case reported delayed paraplegia and graft infection as postoperative complications. The complications were partially removed 3 months later after rehabilitation. Conclusion Retroperitoneal approach is a safe and feasible technique, which associated with a low incidence of postoperative pulmonary complications.展开更多
Background: Mastitis, an infection caused by Gram-positive bacteria, produces udder inflammation and oxidative injury in milk-producing mammals. Toll-like receptor 2(TLR2) is important for host recognition of invad...Background: Mastitis, an infection caused by Gram-positive bacteria, produces udder inflammation and oxidative injury in milk-producing mammals. Toll-like receptor 2(TLR2) is important for host recognition of invading Grampositive microbes. Over-expression of TLR2 in transgenic dairy goats is a useful model for studying various aspects of infection with Gram-positive bacteria, in vivo.Methods: We over-expressed TLR2 in transgenic dairy goats. Pam3CSK4, a component of Gram-positive bacteria,triggered the TLR2 signal pathway by stimulating the monocytes-macrophages from the TLR2-positive transgenic goats, and induced over-expression of activator protein-1(AP-1), phosphatidylinositol 3-kinase(PI3K) and transcription factor nuclear factor kappa B(NF-κB) and inflammation factors downstream of the signal pathway.Results: Compared with wild-type controls, measurements of various oxidative stress-related molecules showed that TLR2, when over-expressed in transgenic goat monocytes-macrophages, resulted in weak lipid damage, high level expression of anti-oxidative stress proteins, and significantly increased m RNA levels of transcription factor NF-E2-related factor-2(Nrf2) and the downstream gene, heme oxygenase-1(HO-1). When Pam3CSK4 was used to stimulate ear tissue in vivo the HO-1 protein of the transgenic goats had a relatively high expression level.Conclusions: The results indicate that the oxidative injury in goats over-expressing TLR2 was reduced following Pam3CSK4 stimulation. The underlying mechanism for this reduction was increased expression of the anti-oxidation gene HO-1 by activation of the Nrf2 signal pathway.展开更多
Recent studies have shown that the highly susceptibility to oxidation ofα-linolenic acid(ALA)enriched emulsion delivery system was harmful for human health which limited their incorporation into functional food.Impac...Recent studies have shown that the highly susceptibility to oxidation ofα-linolenic acid(ALA)enriched emulsion delivery system was harmful for human health which limited their incorporation into functional food.Impacts of natural sesamol(SOH)and sesamin(SES)on stability of flaxseed oil-in-water emulsion were investigated.Results showed that SOH indicated higher antioxidant activity and significantly prolonged the time of emulsion oil-off by retarding oil droplet aggregation in a dose dependent manner throughout storage.Moreover,SOH showed substantial extended lag phase of lipid oxidation products,especially for secondary oxidation products(thiobarbituric acid-reactive substances,TBARS),with a maximum reduction of 70%with 800 M dosage.The antioxidative efficiency of SOH might relate to its strong ability of scavenging free radical and chelate transition metal.Furthermore,SOH significantly enhanced interfacial barrier property and reduced permeation rate of peroxyl radical across emulsion interface by hydrogen bonds between sugar groups of saponin molecules and SOH.However,no obvious change in barrier property of emulsion was observed in SES.SOH improved physicochemical property of flaxseed oil-in-water emulsion with higher antioxidant activity and stronger interfacial barrier property,so that it could be serve as plant-based antioxidant in oil-in-water emulsion delivery system.展开更多
Abstract Cuticular wax covers the surface of the apple epidermis and plays an important role in water loss and pathogen resistance.However,little is known about wax biosynthesis during apple fruit development.In this ...Abstract Cuticular wax covers the surface of the apple epidermis and plays an important role in water loss and pathogen resistance.However,little is known about wax biosynthesis during apple fruit development.In this study,the morphological structure and chemical composition of wax and the transcription patterns of wax-related genes were investigated in the'Red Delicious'and'Golden Delicious'cultivars.The results showed that accumulation of the waxy layer was synchronized with enlargement and maturation of fruit.The crystal structure,major chemical components(very long chain fatty acids and triterpenes)of wax and the expression levels of wax-related genes varied significantly 90 days after flowering(DAF),indicating that the critical period for biosynthesis of cuticular wax was about 90 DAF.This finding is valuable for further study of the regulatory mechanism of wax biosynthesis at both the molecular and physiological levels.展开更多
To improve the security and reliability of a distribution network, several issues, such as influences of operation con-strains, real-time load margin calculation, and online security level evaluation, are with great s...To improve the security and reliability of a distribution network, several issues, such as influences of operation con-strains, real-time load margin calculation, and online security level evaluation, are with great significance. In this pa-per, a mathematical model for load capability online assessment of a distribution network is established, and a repeti-tive power flow calculation algorithm is proposed to solve the problem as well. With assessment on three levels: the entire distribution network, a sub-area of the network and a load bus, the security level of current operation mode and load transfer capability during outage are thus obtained. The results can provide guidelines for prevention control, as well as restoration control. Simulation results show that the method is simple, fast and can be applied to distribution networks belonged to any voltage level while taking into account all of the operation constraints.展开更多
This paper examines whether and how investors reacted to the pronouncements related to International Accounting Standards (IAS) 19R. Using a sample of 401 European firms reporting pension and retirement expense duri...This paper examines whether and how investors reacted to the pronouncements related to International Accounting Standards (IAS) 19R. Using a sample of 401 European firms reporting pension and retirement expense during the period of 2006-2011, this paper finds negative abnormal returns around the pension project initiation by the International Accounting Standards Board (IASB). More importantly, the abnormal returns are more negative for firms with higher financial leverage and lower ratios of net periodic pension cost to net income, but less negative for firms in countries with weak creditor rights (CR) and infrequent use of the corridor approach under IAS 19. Additionally, the effects of financial leverage and the ratio of net periodic pension cost to net income on the abnormal returns are more pronounced for smaller firms. Overall, the results are consistent with the view that recognition of previously disclosed off-balance-sheet pension liabilities as required by IAS 19R increases debt contracting costs, and highlight the importance of considering firm size and CR in international tests of debt contracting theory.展开更多
Based on the analysis of the existing hard IP core testing technology, the hard IP core nondestructive testing technology was studied, according to the verification requirements of a large number of hard IP core preci...Based on the analysis of the existing hard IP core testing technology, the hard IP core nondestructive testing technology was studied, according to the verification requirements of a large number of hard IP core precise and fast testing. Combined with the external automatic test equipment (ATE) and the on-chip evaluation circuit, a general evaluation system of simulating user system on chip (SOC) with signal timing calibration and compensation by software and hardware compensation structures were introduced to realize the function, performance and reliability verification of the hard IP core. The design and verification of a random access memory (SRAM) hard IP core based on an on-chip evaluation circuit was actually completed, and the key timing parameters of the hard IP core were tested. The address setup time parameter was taken as an example to analyze the specific testing method and the test results were obtained. With this testing technology, the accuracy of testing the timing parameters of hard IP core can reach pS level, compared with the hard IP core packaged test, the accuracy of the result data is fully reflected.展开更多
基金supported by the Hunan Provincial Science and Technology Department Project(2015WK3012)the National Natural Science Foundation of China(No.81571021)+3 种基金R&D of Key Project of Hunan Provincial Science and Technology Department(2022SK2010)R&D of Key Technology of Light Metal Air Battery,Transformation and Industrialization of Scientific and Technological Achievements of Hunan Province(2020GK2071)R&D of Key Technology and Materials of Magnesium Air Battery,Transformation of Scientific and Technological Achievements of Changsha City(Kh2005186)Technology Fundation(2021JCJQ-JJ-0432)。
文摘The repair and regeneration of bone defects are highly challenging orthopedic problems.Recently,Mg-based implants have gained popularity due to their unique biodegradation and elastic modulus similar to that of human bone.The aim of our study is to develop a magnesium alloy with a controllable degradation that can closely match bone tissue to help injuries heal in vivo and avoid cytotoxicity caused by a sudden increase in ion concentration.In this study,we prepared and modified Mg-3Zn,Mg-3Zn-1Y,and Mg-2Zn-1Mn by hot extrusion,and used Mg-2.5Y-2.5Nd was as a control.We then investigated the effect of additions of Y and Mn on alloys'properties.Our results show that Mn and Y can improve not only compression strength but also corrosion resistance.The alloy Mg-2Zn-1Mn demonstrated good cytocompatibility in vitro,and for this reason we selected it for implantation in vivo.The degraded Mg-2Zn-1Mn implanted a bone defect area did not cause obvious rejection and inflammatory reaction,and the degradation products left no signs of damage to the heart,liver,kidney,or brain.Furthermore,we find that Mg-2Zn-1Mn can promote an osteoinductive response in vivo and the formation of bone regeneration.
文摘The introduction of alleles into commercial crop breeding pipelines is both time consuming and costly.Two technologies that are disrupting traditional breeding processes are doubled haploid(DH)breeding and genome editing(GE).Recently,these techniques were combined into a GE trait delivery system called HI-Edit(Haploid Inducer-Edit).In HI-Edit,the pollen of a haploid inducer line is reprogrammed to deliver GE traits to any variety,obviating recurrent selection.For HI-Edit to operate at scale,an efficient transformable HI line is needed,but most maize varieties are recalcitrant to transformation,and haploid inducers are especially difficult to transform given their aberrant reproductive behaviors.Leveraging marker assisted selection and a three-tiered testing scheme,we report the development of new Iodent and Stiff Stalk maize germplasm that are transformable,have high haploid induction rates,and exhibit a robust,genetically-dominant anthocyanin native trait that may be used for rapid haploid identification.We show that transformation of these elite‘‘HI-Edit”lines is enhanced using the BABYBOOM and WUSCHEL morphogenetic factors.Finally,we evaluate the HI-Edit performance of one of the lines against both Stiff Stalk and non-Stiff Stalk testers.The strategy and results of this study should facilitate the development of commercially scalable HI-Edit systems in diverse crops.
基金supported by the Technology Star of Shanghai Institute of Applied Physics,Chinese Academy of Sciences(No.E2551130)the Youth Innovation Promotion Association,Chinese Academy of Sciences(No.E2292202).
文摘The evolution of the microstructure and tensile rupture mechanism of laser welds in UNS N10003 alloy exposed to 700℃are investigated.Fine M_(6)C carbides precipitate around the primary eutectic M_(6)C-carbides in the fusion zone after 100 h of exposure.During long-term thermal exposure,the size of the fine M_(6)C carbides increased.The eutectic M_(6)C-carbides in the as-welded fusion zone transformed into spherical M_(6)C carbides as the exposure time extends to 10000 h.Additionally,the spherical M_(6)C particles exhibit size coarsening with increasing exposure time.The tensile properties of the welded joints are not adversely affected by the evolution of eutectic M_(6)C-carbides and the coarsening of M_(6)C carbides.
基金funded by the Inner Mongolia Autonomous Region Science and Technology Program(2021GG0198)Shaanxi Science,Technology Department(No.2021ZDLSF05-01,2022SF-327)China Geological Survey(DD20190351,DD20221751).
文摘Water table configuration gives rise to hierarchically nested groundwater flow systems.However,there remains a lack of comprehensive understanding regarding the controlling factors of water table and its impact on flow systems.Moreover,it remains challenging to identify characteristics of water table space variation through limited groundwater observations at the regional scale.Based on two ideal two-dimensional cross-section analytical models,this study presents a simplified approach to preliminarily assess the nonlinear interactions between water table variation and three driving factors:Topography,geol-ogy and climate.Two criteria,C1 and C2,are utilized to address issues at different scales ranging from basin to local:(i)the influence of various factors on water table configuration;and(ii)the influence of water table on groundwater flow pattern.Then,the Ordos Plateau is taken as an example to explore the role of the water table in nested groundwater systems using the provided approach and criterion.The applica-tion of this approach in the Ordos Plateau demonstrates its appropriateness as a practical method for prelim-inarily determining the characteristics of water table configuration and its impact on flow systems.The study explores the mechanism influencing spatial variation in the water table and improves understanding of the interaction between topography,geology,and climate on groundwater flow patterns.
基金supported by the Open Project of State Key Laboratory of Environment-friendly Energy Materials, China (No. 19kfgh07)R&D of Key Technology of Light Metal Air Battery, Transformation and Industrialization of Scientific and Technological Achievements of Hunan Province, China (No. 2020GK2071)R&D of Key Technology and Materials of Magnesium Air Battery, Transformation of Scientific and Technological Achievements of Changsha City, China (No. Kh2005186)。
文摘BACKGROUND Gastric cancer(GC)is one of the most common cancers and has a poor prognosis.Treatment of GC has remained unchanged over the past few years.AIM To investigate the potential therapeutic targets and related regulatory biomarkers of GC.METHODS We obtained the public GC transcriptome sequencing dataset from the Gene Expression Omnibus database.The datasets contained 348 GC tissues and 141 healthy tissues.In total,251 differentially expressed genes(DEGs)were identified,including 187 down-regulated genes and 64 up-regulated genes.The DEGs’enriched functions and pathways include Progesterone-mediated oocyte maturation,cell cycle,and oocyte meiosis,Hepatitis B,and the Hippo signaling pathway.Survival analysis showed that BUB1,MAD2L1,CCNA2,CCNB1,and BIRC5 may be associated with regulation of the cell cycle phase mitotic spindle checkpoint pathway.We selected 26 regulated genes with the aid of the protein-protein interaction network analyzed by Molecular Complex Detection.RESULTS We focused on three critical genes,which were highly expressed in GC,but negatively related to patient survival.Furthermore,we found that knockdown of Yu K et al.Biochemical analysis in GC WJCC https://www.wjgnet.com 5024 July 26,2023 Volume 11 Issue 21 BIRC5,TRIP13 or UBE2C significantly inhibited cell proliferation and induced cell apoptosis.In addition,knockdown of BIRC5,TRIP13 or UBE2C increased cellular sensitivity to cisplatin.CONCLUSION Our study identified significantly upregulated genes in GC with a poor prognosis using integrated bioinformatics methods.
基金Project supported by the National Natural Science Foundation of China(No.11772089)the Fundamental Research Funds for the Central Universities of China(Nos.N170308028 and N170306004)+1 种基金the Program for the Innovative Talents of Higher Learning Institutions of Liaoning of China(No.LR2017035)the Liaoning Revitalization Talents Program of China(No.XLYC1807008)
文摘A rotating pre-twisted and inclined cantilever beam model (RPICBM) with the flapwise-chordwise-axial-torsional coupling is established with the Hamilton principle and the finite element (FE) method. The effectiveness of the model is verified via comparisons with the literatures and the FE models in ANSYS. The effects of the setting and pre-twisted angles on the dynamic responses of the RPICBM are analyzed. The results show that:(i) the increase in the setting or pre-twisted angle results in the increases in the first-order flapwise and torsional frequencies while the decrease in the first-order chordwise frequency under rotating conditions;(ii) a positive/negative setting angle leads to a positive/negative constant component, while a positive/negative pre-twisted angle leads to a negative/positive constant component;(iii) when the rotation speed is non-zero, the pre-twisted angle or non-zero setting angle will result in the coupled flapwise-chordwiseaxial- torsional vibration of the RPICBM under axial base excitation.
基金The authors acknowledge the Project(81472058)sup-ported by the National Natural Science Foundation of Chinathe financial support of the 2015 ShanDong province project of outstanding subject talent group.the project(LSD-KB1806)+2 种基金supported by the foundation of National Key labo-ratory of Shock Wave and Detonation Physics and the project(11802284)supported by the National Natural Science Foun-dation of China.The project(2017GK2120)supported by the Key Research and Development Program of Hunan Province and the Natural Science Foundation of Hunan Province of China(2018JJ2506).
文摘For high corrosion resistance and extensively modified biodegradable Mg-based alloys and composites for bone implants,a new Mgbased matrix model prepared by powder metallurgy is discussed and developed.In this research,Mg-5 wt.%Zn alloys were selected as a case.And they were impacted by hot extrusion and aging treatments to construct microstructure with different characteristics.Their selfforming corrosion product layer in Ringer’s solution,biodegradable behavior and corrosion mechanism were minutely investigated by in vitro degradation,electrochemical corrosion and cytocompatibility.The results demonstrated the extruded Mg-5 wt.%Zn alloy aged for 96 h showed high corrosion resistance,good biocompatibility for L929 and excellent ability of maintaining sample integrity during the immersion.Significantly,the alloy showed fine-grain microstructure and uniform distributed hundred nano-sized second phases,which promoted the formation of the uniform and smooth corrosion product layer at the beginning of immersion.The corrosion product layer was more stable in chloride containing aqueous solution and could be directly formed and repaired quickly,which effectively protected the matrix from further corrosion.In addition,an ideal model of Mg-based matrix for bone tissue engineering was tried to presume and propose by discussing the causal relationship between microstructure and bio-corrosion process.
文摘Objective To describe a hybrid endovascular procedure for aorta repair with different kinds of bypass followed by concomitant placement of stent graft in the aorta. Methods From June 2007 to May 2008, 5 consecutive patients who presented with aortic aneurysm or dissection were treated with a new hybrid aorta repair technique. Complete surgical rerouting of supra-aortic vessels was simultaneously created by endovascular repair of aortic arch aneurysm with stent graft. Hybrid left carotid-subclavian bypass with stent graft deployment covering the ostium of the left subclavian artery was performed in a Debakey type III aortic dissection case. The supra-aortic branch was revascularized in 2 cases from ascending aorta to bilateral common carotid arteries using a 16-8 mm bifurcated graft, then total aortic arch and descending artery was occluded with stent-graft. The left carotid artery to the left subclavian artery bypass was created in 1 case, followed by stent-graft deployment. Two cases of infrarenal abdominal aortic aneurysm underwent left external iliac artery to left internal iliac artery bypass by a retroperineal route, then hybrid procedure was performed with bifurcated stent-graft. All stent grafts were deployed via a retrograde femoral artery approach in 5 patients. Results Technical success with complete aneurysmal exclusion was achieved in all patients. There was no incidence of encloleak. During a follow-up period of 2 to 10 months, documented perioperative neurologic events did not occur in all patients. One patient suffered from adult respiratory distress syndrome. After received tracheostomy, he recovered later. There was one death resulting from a postoperative myocar- dial infarction. Conclusion Hybrid arch repair provides an alternative therapy to patients otherwise considered prohibitively high risk for traditional open arch and thoracoabdominal aorta repair.
基金This work was supported by the project of China Geology Survey(DD20190315)Innovation Capability Support Program of Shaanxi(2019TD-040)+1 种基金“Integration of Groundwater Resources Assessment Results in Key Areas of Northwest China”programKey Laboratory of Groundwater and Ecology in Arid and Semi-arid Areas of China Geological Survey.
文摘Glaciers are crucial water resources for arid inland rivers in Northwest China.In recent decades,glaciers are largely experiencing shrinkage under the climate-warming scenario,thereby exerting tremendous influences on regional water resources.The primary role of understudying watershed scale glacier changes under changing climatic conditions is to ensure sustainable utilization of regional water resources,to prevent and mitigate glacier-related disasters.This study maps the current(2020)distribution of glacier boundaries across the Kaidu-Kongque river basin,south slope of Tianshan Mountains,and monitors the spatial evolution of glaciers over five time periods from 2000-2020 through thresholded band ratios approach,using 25 Landsat images at 30 m resolution.In addition,this study attempts to understand the role of climate characteristics for variable response of glacier area.The results show that the total area of glaciers was 398.21 km^(2)in 2020.The glaciers retreated by about 1.17 km^(2)/a(0.26%/a)from 2000 to 2020.The glaciers were reducing at a significantly rapid rate between 2000 and 2005,a slow rate from 2005 to 2015,and an accelerated rate during 2015-2020.The meteorological data shows slight increasing trends of mean annual temperature(0.02℃/a)and annual precipitation(2.07 mm/a).The correlation analysis demonstrates that the role of temperature presents more significant correlation with glacier recession than precipitation.There is a temporal hysteresis in the response of glacier change to climate change.Increasing trend of temperature in summer proves to be the driving force behind the Kaidu-Kongque basin glacier recession during the recent 20 years.
文摘Objective To study the coronary microvascular function in older patients with heart failure with preserved ejection fraction (HFpEF) using an invasive pressure–temperature sensor guidewire. Methods Patients undergoing echocardiography and cardiac catheterization examinations for exertional dyspnea and a positive stress test were retrospectively enrolled from January 2014 to November 2017, and were allocated into the control group or HFpEF group. The HFpEF group was secondary divided into two groups according to the age of 65 years. Comparing the clinical features and values obtained in examinations between the three groups, multivariate regression analysis was used to analyze the predictors of left ventricle end diastolic pressure (LVEDP). Results There were 87 patients enrolled in this study. The older HFpEF patients (n = 32) were more likely to be female;and had the most comorbidities, such as diabetes mellitus, atrial fibrillation, and chronic kidney dysfunction (CKD) with a low estimated glomerular filtration rate (eGFR), and had a similar hypertensive prevalence as the adult HFpEF group (n = 24), whose mean LVEDP and index of microcirculatory resistance (IMR) were highest in comparison to the adult HFpEF patients and controls (n = 31). The coronary flow reserve (CFR) in the older HFpEF and adult HFpEF groups was similarly reduced. In the regression analysis, the IMR linearly correlated to LVEDP, and was the only independent predictor of LVEDP. Conclusions An increased IMR and reduced CFR were characteristics of microvascular dysfunction in older HFpEF patients. The IMR independently had a positive linear correlation with LVEDP. Microvascular rarefaction might be a subsequent pathological progression in the development of HFpEF.
文摘BACKGROUND Fulminant lupus myocarditis is a rare but fatal manifestation of systemic lupus erythematosus.Aggressive immunosuppressive treatments are important in its successful management.However,they can significantly damage the immunity and are associated with a considerable risk of infection development and spread.We present a rare and complicated case of a 20-year-old female diagnosed with fulminant lupus myocarditis accompanied by pneumonia.The patient was successfully treated with plasma exchange(PE)for fulminant lupus myocarditis.CASE SUMMARY A 20-year-old Chinese woman presented to the Hematology Department complaining of fatigue and knee pain.Blood test showed anemia and thrombocytopenia.On the second day of hospitalization,she was transferred to the ICU due to dyspnea and hypotension.Autoimmune profiles showed hypocomplementemia and positive antinuclear antibodies.Computer tomography showed an enlarged heart and pneumonia.Ultrasound revealed an enlarged heart with a low left ventricular ejection fraction.Fulminant lupus myocarditis with cardiogenic shock was initially considered.Due to the accompanying pneumonia,aggressive immunosuppression was contraindicated.Her cardiac function remained critical after the initial therapy of intravenous immunoglobulin and corticosteroids at a conventional dose,but she responded well to later PE therapy plus corticosteroids administration.The patient fully recovered with normal cardiac function.CONCLUSION This case indicates that PE is a valuable treatment choice without adverse effects of immunosuppression in patients with fulminant lupus myocarditis and coexisting infection.
文摘Objective To investigate the application of the retroperitoneal approach in aortic surgery. Methods We collected and analyzed data of 7 patients in Macao who presented with aortic diseases from 2007 to 2008 and were treated with aorta repair through retroperitoneal approach. Demographic features as well as intraoperative and postoperative data were analyzed. One case of thoracoabdominal aneurysm and 4 cases of abdominal aneurysm received artificial graft, among which hybrid iliac artery reconstruction with Zenith stent covering the ostium of the left subclavian artery was performed in 2 cases of infrarenal abdominal aneurysm. Aortic-iliac artery bypass was performed in 2 cases of aortoiliac occlusion. Results No operative or early postoperative death was observed. No perioperative intestinal adhesion or ureteral obstruction was found. One case reported delayed paraplegia and graft infection as postoperative complications. The complications were partially removed 3 months later after rehabilitation. Conclusion Retroperitoneal approach is a safe and feasible technique, which associated with a low incidence of postoperative pulmonary complications.
基金supported by grants from National Transgenic Creature Breeding Grand Project(2014ZX08008-005)Chinese Universities Scientific Fund(2014BH032)Natural Science Foundation of China(31501953, 31471352, 31471400 and 31171380)
文摘Background: Mastitis, an infection caused by Gram-positive bacteria, produces udder inflammation and oxidative injury in milk-producing mammals. Toll-like receptor 2(TLR2) is important for host recognition of invading Grampositive microbes. Over-expression of TLR2 in transgenic dairy goats is a useful model for studying various aspects of infection with Gram-positive bacteria, in vivo.Methods: We over-expressed TLR2 in transgenic dairy goats. Pam3CSK4, a component of Gram-positive bacteria,triggered the TLR2 signal pathway by stimulating the monocytes-macrophages from the TLR2-positive transgenic goats, and induced over-expression of activator protein-1(AP-1), phosphatidylinositol 3-kinase(PI3K) and transcription factor nuclear factor kappa B(NF-κB) and inflammation factors downstream of the signal pathway.Results: Compared with wild-type controls, measurements of various oxidative stress-related molecules showed that TLR2, when over-expressed in transgenic goat monocytes-macrophages, resulted in weak lipid damage, high level expression of anti-oxidative stress proteins, and significantly increased m RNA levels of transcription factor NF-E2-related factor-2(Nrf2) and the downstream gene, heme oxygenase-1(HO-1). When Pam3CSK4 was used to stimulate ear tissue in vivo the HO-1 protein of the transgenic goats had a relatively high expression level.Conclusions: The results indicate that the oxidative injury in goats over-expressing TLR2 was reduced following Pam3CSK4 stimulation. The underlying mechanism for this reduction was increased expression of the anti-oxidation gene HO-1 by activation of the Nrf2 signal pathway.
基金financial support from the National Natural Science Foundation of China (31771938)the Earmarked Fund for China Agriculture Research System (CARS-14)partly based upon work supported by the National Institute of Food and Agriculture, USDA, Massachusetts Agricultural Experiment Station (MAS00491) and USDA, AFRI Grants (2016-08782)
文摘Recent studies have shown that the highly susceptibility to oxidation ofα-linolenic acid(ALA)enriched emulsion delivery system was harmful for human health which limited their incorporation into functional food.Impacts of natural sesamol(SOH)and sesamin(SES)on stability of flaxseed oil-in-water emulsion were investigated.Results showed that SOH indicated higher antioxidant activity and significantly prolonged the time of emulsion oil-off by retarding oil droplet aggregation in a dose dependent manner throughout storage.Moreover,SOH showed substantial extended lag phase of lipid oxidation products,especially for secondary oxidation products(thiobarbituric acid-reactive substances,TBARS),with a maximum reduction of 70%with 800 M dosage.The antioxidative efficiency of SOH might relate to its strong ability of scavenging free radical and chelate transition metal.Furthermore,SOH significantly enhanced interfacial barrier property and reduced permeation rate of peroxyl radical across emulsion interface by hydrogen bonds between sugar groups of saponin molecules and SOH.However,no obvious change in barrier property of emulsion was observed in SES.SOH improved physicochemical property of flaxseed oil-in-water emulsion with higher antioxidant activity and stronger interfacial barrier property,so that it could be serve as plant-based antioxidant in oil-in-water emulsion delivery system.
基金supported by grants from the National Key Research and Development Program(2018YFD1000200)the National Natural Science Foundation of China(32072539 and 31772275).
文摘Abstract Cuticular wax covers the surface of the apple epidermis and plays an important role in water loss and pathogen resistance.However,little is known about wax biosynthesis during apple fruit development.In this study,the morphological structure and chemical composition of wax and the transcription patterns of wax-related genes were investigated in the'Red Delicious'and'Golden Delicious'cultivars.The results showed that accumulation of the waxy layer was synchronized with enlargement and maturation of fruit.The crystal structure,major chemical components(very long chain fatty acids and triterpenes)of wax and the expression levels of wax-related genes varied significantly 90 days after flowering(DAF),indicating that the critical period for biosynthesis of cuticular wax was about 90 DAF.This finding is valuable for further study of the regulatory mechanism of wax biosynthesis at both the molecular and physiological levels.
文摘To improve the security and reliability of a distribution network, several issues, such as influences of operation con-strains, real-time load margin calculation, and online security level evaluation, are with great significance. In this pa-per, a mathematical model for load capability online assessment of a distribution network is established, and a repeti-tive power flow calculation algorithm is proposed to solve the problem as well. With assessment on three levels: the entire distribution network, a sub-area of the network and a load bus, the security level of current operation mode and load transfer capability during outage are thus obtained. The results can provide guidelines for prevention control, as well as restoration control. Simulation results show that the method is simple, fast and can be applied to distribution networks belonged to any voltage level while taking into account all of the operation constraints.
文摘This paper examines whether and how investors reacted to the pronouncements related to International Accounting Standards (IAS) 19R. Using a sample of 401 European firms reporting pension and retirement expense during the period of 2006-2011, this paper finds negative abnormal returns around the pension project initiation by the International Accounting Standards Board (IASB). More importantly, the abnormal returns are more negative for firms with higher financial leverage and lower ratios of net periodic pension cost to net income, but less negative for firms in countries with weak creditor rights (CR) and infrequent use of the corridor approach under IAS 19. Additionally, the effects of financial leverage and the ratio of net periodic pension cost to net income on the abnormal returns are more pronounced for smaller firms. Overall, the results are consistent with the view that recognition of previously disclosed off-balance-sheet pension liabilities as required by IAS 19R increases debt contracting costs, and highlight the importance of considering firm size and CR in international tests of debt contracting theory.
文摘Based on the analysis of the existing hard IP core testing technology, the hard IP core nondestructive testing technology was studied, according to the verification requirements of a large number of hard IP core precise and fast testing. Combined with the external automatic test equipment (ATE) and the on-chip evaluation circuit, a general evaluation system of simulating user system on chip (SOC) with signal timing calibration and compensation by software and hardware compensation structures were introduced to realize the function, performance and reliability verification of the hard IP core. The design and verification of a random access memory (SRAM) hard IP core based on an on-chip evaluation circuit was actually completed, and the key timing parameters of the hard IP core were tested. The address setup time parameter was taken as an example to analyze the specific testing method and the test results were obtained. With this testing technology, the accuracy of testing the timing parameters of hard IP core can reach pS level, compared with the hard IP core packaged test, the accuracy of the result data is fully reflected.