This paper proposes a novel grading method of apples,in an automated grading device that uses convolutional neural networks to extract the size,color,texture,and roundness of an apple.The developed machine learning me...This paper proposes a novel grading method of apples,in an automated grading device that uses convolutional neural networks to extract the size,color,texture,and roundness of an apple.The developed machine learning method uses the ability of learning representative features by means of a convolutional neural network(CNN),to determine suitable features of apples for the grading process.This information is fed into a one-to-one classifier that uses a support vector machine(SVM),instead of the softmax output layer of the CNN.In this manner,Yantai apples with similar shapes and low discrimination are graded using four different approaches.The fusion model using both CNN and SVM classifiers is much more accurate than the simple k-nearest neighbor(KNN),SVM,and CNN model when used separately for grading,and the learning ability and the generalization ability of the model is correspondingly increased by the combined method.Grading tests are carried out using the automated grading device that is developed in the present work.It is verified that the actual effect of apple grading using the combined CNN-SVM model is fast and accurate,which greatly reduces the manpower and labor costs of manual grading,and has important commercial prospects.展开更多
In this paper,an automated system and methodology for nondestructive sorting of apples are presented.Different from the traditional manual grading method,the automated,nondestructive sorting equipment can improve the ...In this paper,an automated system and methodology for nondestructive sorting of apples are presented.Different from the traditional manual grading method,the automated,nondestructive sorting equipment can improve the production efficiency and the grading speed and accuracy.Most popular apple quality detection and grading methods use two-dimensional(2D)machine vision detection based on a single charge-coupled device(CCD)camera detect the external quality.Our system integrates a 3D structured laser into an existing 2D sorting system,which provides the addition third dimension to detect the defects in apples by using the curvature of the structured light strips that are acquired from the optical system of the machine.The curvature of the structured light strip will show the defects in the apple surface.Other features such as color,texture,shape,size and 3D information all play key roles in determining the grade of an apple,which can be determined using a series of feature extraction methods.After feature extraction,a method based on principal component analysis(PCA)for data dimensionality reduction is applied to the system.Furthermore,a comprehensive classification method based on fuzzy neural network(FNN),which is a combination of knowledge-based and model-based method,is used in this paper as the classifier.Preliminary experiments are conducted to verity the feasibility and accuracy of the proposed sorting system.展开更多
Sentiment word embedding has been extensively studied and used in sentiment analysis tasks.However,most existing models have failed to differentiate high-frequency and low-frequency words.Accordingly,the sentiment inf...Sentiment word embedding has been extensively studied and used in sentiment analysis tasks.However,most existing models have failed to differentiate high-frequency and low-frequency words.Accordingly,the sentiment information of low-frequency words is insufficiently captured,thus resulting in inaccurate sentiment word embedding and degradation of overall performance of sentiment analysis.A Bayesian estimation-based sentiment word embedding(BESWE)model,which aims to precisely extract the sentiment information of low-frequency words,has been proposed.In the model,a Bayesian estimator is constructed based on the co-occurrence probabilities and sentiment proba-bilities of words,and a novel loss function is defined for sentiment word embedding learning.The experimental results based on the sentiment lexicons and Movie Review dataset show that BESWE outperforms many state-of-the-art methods,for example,C&W,CBOW,GloVe,SE-HyRank and DLJT1,in sentiment analysis tasks,which demonstrate that Bayesian estimation can effectively capture the sentiment information of low-frequency words and integrate the sentiment information into the word embedding through the loss function.In addition,replacing the embedding of low-frequency words in the state-of-the-art methods with BESWE can significantly improve the performance of those methods in sentiment analysis tasks.展开更多
Demineralized bone matrix(DBM)has been widely used clinically for dental,craniofacial and skeletal bone repair,as an osteoinductive and osteoconductive material.3D printing(3DP)enables the creation of bone tissue engi...Demineralized bone matrix(DBM)has been widely used clinically for dental,craniofacial and skeletal bone repair,as an osteoinductive and osteoconductive material.3D printing(3DP)enables the creation of bone tissue engineering scaffolds with complex geometries and porosity.Photoreactive methacryloylated gelatin nanoparticles(GNP-MAs)3DP inks have been developed,which display gel-like behavior for high print fidelity and are capable of post-printing photocrosslinking for control of scaffold swelling and degradation.Here,novel DBM nanoparticles(DBM-NPs,∼400 nm)were fabricated and characterized prior to incorporation in 3DP inks.The objectives of this study were to determine how these DBM-NPs would influence the printability of composite colloidal 3DP inks,assess the impact of ultraviolet(UV)crosslinking on 3DP scaffold swelling and degradation and evaluate the osteogenic potential of DBM-NP-containing composite colloidal scaffolds.The addition of methacryloylated DBM-NPs(DBM-NP-MAs)to composite colloidal inks(100:0,95:5 and 75:25 GNP-MA:DBM-NP-MA)did not significantly impact the rheological properties associated with printability,such as viscosity and shear recovery or photocrosslinking.UV crosslinking with a UV dosage of 3 J/cm2 directly impacted the rate of 3DP scaffold swelling for all GNP-MA:DBM-NP-MA ratios with an∼40%greater increase in scaffold area and pore area in uncrosslinked versus photocrosslinked scaffolds over 21 days in phosphate-buffered saline(PBS).Likewise,degradation(hydrolytic and enzymatic)over 21 days for all DBM-NP-MA content groups was significantly decreased,∼45%less in PBS and collagenase-containing PBS,in UV-crosslinked versus uncrosslinked groups.The incorporation of DBM-NP-MAs into scaffolds decreased mass loss compared to GNP-MA-only scaffolds during collagenase degradation.An in vitro osteogenic study with bone marrow-derived mesenchymal stem cells demonstrated osteoconductive properties of 3DP scaffolds for the DBM-NP-MA contents examined.The creation of photoreactive DBM-NP-MAs and their application in 3DP provide a platform for the development of ECM-derived colloidal materials and tailored control of biochemical cue presentation with broad tissue engineering applications.展开更多
Chronic wounds include,but are not limited to,radiation ulcers,pressure ulcers,vascular ulcers and diabetic foot ulcers.These chronic wounds can persist for years without healing and severe ulcers may lead to amputati...Chronic wounds include,but are not limited to,radiation ulcers,pressure ulcers,vascular ulcers and diabetic foot ulcers.These chronic wounds can persist for years without healing and severe ulcers may lead to amputation.Unfortunately,the underlying pathologies of refractory chronic wounds are not fully characterized,and new treatments are urgently needed.Recently,increasing evidence has indicated that cell senescence plays an important role in the development of chronic wounds,and preventing cell senescence or removing senescent cells holds promise as a new therapeutic strategy.In this review,we aim to probe these latest findings to promote the understanding of cellular senescence in the pathological process and potential management of chronic wounds.展开更多
As an important secondary photochemical pollutant,peroxyacetyl nitrate(PAN)has been studied over decades,yet its simulations usually underestimate the corresponding observations,especially in polluted areas.Recent obs...As an important secondary photochemical pollutant,peroxyacetyl nitrate(PAN)has been studied over decades,yet its simulations usually underestimate the corresponding observations,especially in polluted areas.Recent observations in north China found unusually high concentrations of PAN during wintertime heavy haze events,but the current model still cannot reproduce the observations,and researchers speculated that nitrous acid(HONO)played a key role in PAN formation.For the first time we systematically assessed the impact of potential HONO sources on PAN formation mechanisms in eastern China using the Weather Research and Forecasting/Chemistry(WRF-Chem)model in February of 2017.The results showed that the potential HONO sources significantly improved the PAN simulations,remarkably accelerated the RO x(sum of hydroxyl,hydroperoxyl,and organic peroxy radicals)cycles,and resulted in 80%–150%enhancements of PAN near the ground in the coastal areas of eastern China and 10%–50%enhancements in the areas around 35–40°N within 3 km during a heavy haze period.The direct precursors of PAN were aldehyde and methylglyoxal,and the primary precursors of PAN were alkenes with C>3,xylenes,propene and toluene.The above results suggest that the potential HONO sources should be considered in regional and global chemical transport models when conducting PAN studies.展开更多
In this study, we theoretically investigate the strain effect on the orientation-dependent high-order harmonic generation(HHG) of monolayer aluminum nitride(Al N) by solving the multiband semiconductor Bloch equations...In this study, we theoretically investigate the strain effect on the orientation-dependent high-order harmonic generation(HHG) of monolayer aluminum nitride(Al N) by solving the multiband semiconductor Bloch equations in strong laser fields. Our simulations denote that the efficiency of the orientation-dependent HHG is considerably enhanced when a 15% biaxial tensile strain is applied to Al N, which is attributed to the downshifting energy level of the conduction band. Furthermore, the odd-even feature in the orientation-dependent high harmonic spectra owing to the strain is considerably different when compared with that in the case without strain. The enhanced quantum interference between different energy bands in strained Al N around the Γ-M direction is responsible for the observed odd-even distributions of the orientation-dependent HHG. This study helps to better understand the HHG in solids by tuning their electronic structures.展开更多
Background:Human positive cofactor 4(PC4)was initially characterized as a multifunctional transcriptional cofactor,but its role in skin wound healing is still unclear.The purpose of this study was to explore the role ...Background:Human positive cofactor 4(PC4)was initially characterized as a multifunctional transcriptional cofactor,but its role in skin wound healing is still unclear.The purpose of this study was to explore the role of PC4 in skin wound healing through PC4 knock-in mouse model.Methods:A PC4 knock-in mouse model(PC4^(+/+))with a dorsal full-thickness wound was used to investigate the biological functions of PC4 in skin wound healing.Quantitative PCR,Western blot analysis and immunohistochemistry were performed to evaluate the expression of PC4;Sirius red staining and immunofluorescence were performed to explore the change of collagen deposition and angiogenesis.Proliferation and apoptosis were detected using Ki67 staining and TUNEL assay.Primary dermal fibroblasts were isolated from mouse skin to perform cell scratch experiments,cck-8 assay and colony formation assay.Results:The PC4^(+/+)mice were fertile and did not display overt abnormalities but showed an obvious delay in cutaneous healing of dorsal skin.Histological staining showed insufficient re-epithelialization,decreased angiogenesis and collagen deposition,increased apoptosis and decreased cell proliferation in PC4^(+/+)skin.Our data also showed decreased migration rate and proliferation ability in cultured primary fibroblasts from PC4^(+/+)mice in vitro.Conclusions:This study suggests that PC4 might serve as a negative regulator of skin wound healing in mice.展开更多
Long-lasting phosphorescent （LLP） materials have attracted considerable attention since green and blue emitting persis- tent Eu2＋ doped alkaline earth phosphors were reported in the mid-1990s [1-3]. Over the past f...Long-lasting phosphorescent （LLP） materials have attracted considerable attention since green and blue emitting persis- tent Eu2＋ doped alkaline earth phosphors were reported in the mid-1990s [1-3]. Over the past few decades, a consid- erable effort has been made to design novel LLP materials for a wide range of applications such as emergency lighting, interior decoration, road signs, and in vivo bioimaging [4-6]. For these applications, long persistence times are often desir- able. Two types of active center involved are： emitters and traps in LLP phosphors. Emitters are capable of emitting ra- diation after being excited, and their color is determined by the emission wavelength of the LLP phosphor. Traps states usually do not emit radiation, but store the excitation energy later releasing it to the emitters under thermal disturbance. Thus, traps play an important role in photo-energy storage of LLP phosphors. The trap type and trap distribution are gen- erally associated with lattice defects and/or co-dopants. The overall nature of the trap states determines the persistence in- tensity and time. Thus, design of LLP phosphors focuses on generating suitable trap levels and trap densities.展开更多
This study was to optimize the exercise preconditioning(EP)intensity in protecting from exhaustive exercise-induced cardiac injury(EECI).A total of 98 male Sprague-Dawley rats were divided into 7 groups(n=14):the cont...This study was to optimize the exercise preconditioning(EP)intensity in protecting from exhaustive exercise-induced cardiac injury(EECI).A total of 98 male Sprague-Dawley rats were divided into 7 groups(n=14):the control group(C),the exhaustive exercise group(EE)and the EP+EE groups,which include the V10(53.0%VO_(2max)),V15(58.4%VO_(2max)),V20(67.0%VO_(2max)),V26(74.0%VO_(2max))and V30(80.0%VO_(2max))groups.Except the C group,the other groups were subjected to treadmill running.The serum contents of N terminal pro B type natriuretic peptide(NT-proBNP)and cardiac troponin I(cTn-I)were detected by the enzyme-linked immunosorbent assay method,ECG was recorded,heart function was detected by pressure volume catheter and the activities of mitochondrial electron transfer pathway(ET pathway)complexesⅠ,ⅡandⅣwere measured by high-resolution respiration instrument.Compared to the EE group,the EP groups have shown decrease of NT-proBNP and cTn-I,improvement of mitochondrial respiratory function and car-diac function.Compared to other EP groups,the V26 group has shown significant decrease of myocardial enzymes and improvement of mitochondrial function.The correlation analysis showed the EP effect was proportional to EP intensity in the range of 53.0%VO_(2max)-74.0%VO_(2max).High intensity and long duration of exhaustive exercise caused cardiac injury and EP could decrease serum level of NT-proBNP and cTn-I,improve electrical derangement and the left ventricular function,and raise the activities of ET pathway complexesⅠ,ⅡandⅣ.The protection of EP on EECI was improved as the EP intensity was increased from 53.0%VO_(2max)to 74.0%VO_(2max)and when EP intensity was 74.0%VO_(2max),the effect was the most obvious among all the setting EP groups.展开更多
Many clustered regularly interspaced short palindromic repeat and CRISPR-associated protein 12b(CRISPR-Cas12b)nucleases have been computationally identified,yet their potential for genome editing remains largely unexp...Many clustered regularly interspaced short palindromic repeat and CRISPR-associated protein 12b(CRISPR-Cas12b)nucleases have been computationally identified,yet their potential for genome editing remains largely unexplored.In this study,we conducted a GFP-activation assay screening 13 Cas12b nucleases for mammalian genome editing,identifying five active candidates.Candidatus hydrogenedentes Cas12b(ChCas12b)was found to recognize a straightforward WTN(W=T or A)proto-spacer adjacent motif(PAM),thereby dramatically expanding the targeting scope.Upon optimization of the single guide RNA(sgRNA)scaffold,ChCas12b exhibited activity comparable to SpCas9 across a panel of nine endogenous loci.Additionally,we identified nine mutations enhancing ChCas12b specificity.More importantly,we demonstrated that both ChCas12b and its high-fidelity variant,ChCas12b-D496A,enabled allelespecific disruption of genes harboring single nucleotide polymorphisms(SNPs).These data position ChCas12b and its high-fidelity counterparts as promising tools for both fundamental research and therapeutic applications.展开更多
文摘This paper proposes a novel grading method of apples,in an automated grading device that uses convolutional neural networks to extract the size,color,texture,and roundness of an apple.The developed machine learning method uses the ability of learning representative features by means of a convolutional neural network(CNN),to determine suitable features of apples for the grading process.This information is fed into a one-to-one classifier that uses a support vector machine(SVM),instead of the softmax output layer of the CNN.In this manner,Yantai apples with similar shapes and low discrimination are graded using four different approaches.The fusion model using both CNN and SVM classifiers is much more accurate than the simple k-nearest neighbor(KNN),SVM,and CNN model when used separately for grading,and the learning ability and the generalization ability of the model is correspondingly increased by the combined method.Grading tests are carried out using the automated grading device that is developed in the present work.It is verified that the actual effect of apple grading using the combined CNN-SVM model is fast and accurate,which greatly reduces the manpower and labor costs of manual grading,and has important commercial prospects.
文摘In this paper,an automated system and methodology for nondestructive sorting of apples are presented.Different from the traditional manual grading method,the automated,nondestructive sorting equipment can improve the production efficiency and the grading speed and accuracy.Most popular apple quality detection and grading methods use two-dimensional(2D)machine vision detection based on a single charge-coupled device(CCD)camera detect the external quality.Our system integrates a 3D structured laser into an existing 2D sorting system,which provides the addition third dimension to detect the defects in apples by using the curvature of the structured light strips that are acquired from the optical system of the machine.The curvature of the structured light strip will show the defects in the apple surface.Other features such as color,texture,shape,size and 3D information all play key roles in determining the grade of an apple,which can be determined using a series of feature extraction methods.After feature extraction,a method based on principal component analysis(PCA)for data dimensionality reduction is applied to the system.Furthermore,a comprehensive classification method based on fuzzy neural network(FNN),which is a combination of knowledge-based and model-based method,is used in this paper as the classifier.Preliminary experiments are conducted to verity the feasibility and accuracy of the proposed sorting system.
基金Funding information National Statistical Science Research Project of China,Grant/Award Number:2016LY98Science and Technology Department of Guangdong Province in China,Grant/Award Numbers:2016A010101020,2016A010101021,2016A010101022+2 种基金Characteristic Innovation Projects of Guangdong Colleges and Universities,Grant/Award Numbers:2018KTSCX049,2018GKTSCX069Science and Technology Plan Project of Guangzhou,Grant/Award Numbers:201802010033,201903010013Bidding Project of Laboratory of Language Engineering and Computing of Guangdong University of Foreign Studies,Grant/Award Number:LEC2019ZBKT005。
文摘Sentiment word embedding has been extensively studied and used in sentiment analysis tasks.However,most existing models have failed to differentiate high-frequency and low-frequency words.Accordingly,the sentiment information of low-frequency words is insufficiently captured,thus resulting in inaccurate sentiment word embedding and degradation of overall performance of sentiment analysis.A Bayesian estimation-based sentiment word embedding(BESWE)model,which aims to precisely extract the sentiment information of low-frequency words,has been proposed.In the model,a Bayesian estimator is constructed based on the co-occurrence probabilities and sentiment proba-bilities of words,and a novel loss function is defined for sentiment word embedding learning.The experimental results based on the sentiment lexicons and Movie Review dataset show that BESWE outperforms many state-of-the-art methods,for example,C&W,CBOW,GloVe,SE-HyRank and DLJT1,in sentiment analysis tasks,which demonstrate that Bayesian estimation can effectively capture the sentiment information of low-frequency words and integrate the sentiment information into the word embedding through the loss function.In addition,replacing the embedding of low-frequency words in the state-of-the-art methods with BESWE can significantly improve the performance of those methods in sentiment analysis tasks.
基金support from a National Science Foundation Graduate Research Fellowship(M.R.P.,E.J.,E.Y.J.)the National Institutes of Health(F31 DE030333,K.J.H.+3 种基金P41 EB023833,A.G.M.)the Baylor College of Medicine Medical Science Training Program(K.J.H.),the Scientific and Technological Research Council of Turkey International Research Fellowship Programme for PhD Students(H.O.)a Rubicon Postdoctoral Fellowship from the Dutch Research Council(NWOProject No.019.182 EN.004)(M.D.).
文摘Demineralized bone matrix(DBM)has been widely used clinically for dental,craniofacial and skeletal bone repair,as an osteoinductive and osteoconductive material.3D printing(3DP)enables the creation of bone tissue engineering scaffolds with complex geometries and porosity.Photoreactive methacryloylated gelatin nanoparticles(GNP-MAs)3DP inks have been developed,which display gel-like behavior for high print fidelity and are capable of post-printing photocrosslinking for control of scaffold swelling and degradation.Here,novel DBM nanoparticles(DBM-NPs,∼400 nm)were fabricated and characterized prior to incorporation in 3DP inks.The objectives of this study were to determine how these DBM-NPs would influence the printability of composite colloidal 3DP inks,assess the impact of ultraviolet(UV)crosslinking on 3DP scaffold swelling and degradation and evaluate the osteogenic potential of DBM-NP-containing composite colloidal scaffolds.The addition of methacryloylated DBM-NPs(DBM-NP-MAs)to composite colloidal inks(100:0,95:5 and 75:25 GNP-MA:DBM-NP-MA)did not significantly impact the rheological properties associated with printability,such as viscosity and shear recovery or photocrosslinking.UV crosslinking with a UV dosage of 3 J/cm2 directly impacted the rate of 3DP scaffold swelling for all GNP-MA:DBM-NP-MA ratios with an∼40%greater increase in scaffold area and pore area in uncrosslinked versus photocrosslinked scaffolds over 21 days in phosphate-buffered saline(PBS).Likewise,degradation(hydrolytic and enzymatic)over 21 days for all DBM-NP-MA content groups was significantly decreased,∼45%less in PBS and collagenase-containing PBS,in UV-crosslinked versus uncrosslinked groups.The incorporation of DBM-NP-MAs into scaffolds decreased mass loss compared to GNP-MA-only scaffolds during collagenase degradation.An in vitro osteogenic study with bone marrow-derived mesenchymal stem cells demonstrated osteoconductive properties of 3DP scaffolds for the DBM-NP-MA contents examined.The creation of photoreactive DBM-NP-MAs and their application in 3DP provide a platform for the development of ECM-derived colloidal materials and tailored control of biochemical cue presentation with broad tissue engineering applications.
基金supported by the National Key Research and Development Program(2016YFC1000805)the University Innovation Team Building Program of Chongqing(CXTDG201602020)intramural research project grants(AWS17J007 and 2018-JCJQ-ZQ-001).
文摘Chronic wounds include,but are not limited to,radiation ulcers,pressure ulcers,vascular ulcers and diabetic foot ulcers.These chronic wounds can persist for years without healing and severe ulcers may lead to amputation.Unfortunately,the underlying pathologies of refractory chronic wounds are not fully characterized,and new treatments are urgently needed.Recently,increasing evidence has indicated that cell senescence plays an important role in the development of chronic wounds,and preventing cell senescence or removing senescent cells holds promise as a new therapeutic strategy.In this review,we aim to probe these latest findings to promote the understanding of cellular senescence in the pathological process and potential management of chronic wounds.
基金This work was partially supported by the National Key Research and Development Program of China(No.2017YFC0209801)the National Natural Science Foundation of China(Nos.91544221,41575124)the National Research Program for Key Issues in Air Pollution Control(Nos.DQGG0102,DQGG0103).
文摘As an important secondary photochemical pollutant,peroxyacetyl nitrate(PAN)has been studied over decades,yet its simulations usually underestimate the corresponding observations,especially in polluted areas.Recent observations in north China found unusually high concentrations of PAN during wintertime heavy haze events,but the current model still cannot reproduce the observations,and researchers speculated that nitrous acid(HONO)played a key role in PAN formation.For the first time we systematically assessed the impact of potential HONO sources on PAN formation mechanisms in eastern China using the Weather Research and Forecasting/Chemistry(WRF-Chem)model in February of 2017.The results showed that the potential HONO sources significantly improved the PAN simulations,remarkably accelerated the RO x(sum of hydroxyl,hydroperoxyl,and organic peroxy radicals)cycles,and resulted in 80%–150%enhancements of PAN near the ground in the coastal areas of eastern China and 10%–50%enhancements in the areas around 35–40°N within 3 km during a heavy haze period.The direct precursors of PAN were aldehyde and methylglyoxal,and the primary precursors of PAN were alkenes with C>3,xylenes,propene and toluene.The above results suggest that the potential HONO sources should be considered in regional and global chemical transport models when conducting PAN studies.
基金supported by the National Natural Science Foundation of China(Grant Nos.11974185,11704187,11774175,and 11834004)the Natural Science Foundation of Jiangsu Province(Grant No.BK20170032)。
文摘In this study, we theoretically investigate the strain effect on the orientation-dependent high-order harmonic generation(HHG) of monolayer aluminum nitride(Al N) by solving the multiband semiconductor Bloch equations in strong laser fields. Our simulations denote that the efficiency of the orientation-dependent HHG is considerably enhanced when a 15% biaxial tensile strain is applied to Al N, which is attributed to the downshifting energy level of the conduction band. Furthermore, the odd-even feature in the orientation-dependent high harmonic spectra owing to the strain is considerably different when compared with that in the case without strain. The enhanced quantum interference between different energy bands in strained Al N around the Γ-M direction is responsible for the observed odd-even distributions of the orientation-dependent HHG. This study helps to better understand the HHG in solids by tuning their electronic structures.
基金National Key Research and Development Program,grant/award number:2016YFC1000805University Innovation Team Building Program of Chongqing,grant/award number:CXTDG201602020Intramural research project grants:AWS17J007,2018-JCJQ-ZQ-001.
文摘Background:Human positive cofactor 4(PC4)was initially characterized as a multifunctional transcriptional cofactor,but its role in skin wound healing is still unclear.The purpose of this study was to explore the role of PC4 in skin wound healing through PC4 knock-in mouse model.Methods:A PC4 knock-in mouse model(PC4^(+/+))with a dorsal full-thickness wound was used to investigate the biological functions of PC4 in skin wound healing.Quantitative PCR,Western blot analysis and immunohistochemistry were performed to evaluate the expression of PC4;Sirius red staining and immunofluorescence were performed to explore the change of collagen deposition and angiogenesis.Proliferation and apoptosis were detected using Ki67 staining and TUNEL assay.Primary dermal fibroblasts were isolated from mouse skin to perform cell scratch experiments,cck-8 assay and colony formation assay.Results:The PC4^(+/+)mice were fertile and did not display overt abnormalities but showed an obvious delay in cutaneous healing of dorsal skin.Histological staining showed insufficient re-epithelialization,decreased angiogenesis and collagen deposition,increased apoptosis and decreased cell proliferation in PC4^(+/+)skin.Our data also showed decreased migration rate and proliferation ability in cultured primary fibroblasts from PC4^(+/+)mice in vitro.Conclusions:This study suggests that PC4 might serve as a negative regulator of skin wound healing in mice.
基金supported by the National Natural Science Foundation of China(Grant Nos.21301023,11204024,and 11474046)Program for New Century Excellent Talents in University(Grant No.NCET-13-0702)+3 种基金Science and Technology Project of Liaoning Province(Grant No.2012222009)Natural Science Foundation of Liaoning Province(Grant No.20170540200)Fundamental Research Funds for the Central Universities(Grant Nos.DC201502080302,DC201502080406,DC201502080203,DCPY2016009,and DCPY2016026)Technology Foundation for Selected Overseas Chinese Scholar,Ministry of Human Resources and Social Security of the People’s Republic of China
文摘Long-lasting phosphorescent （LLP） materials have attracted considerable attention since green and blue emitting persis- tent Eu2＋ doped alkaline earth phosphors were reported in the mid-1990s [1-3]. Over the past few decades, a consid- erable effort has been made to design novel LLP materials for a wide range of applications such as emergency lighting, interior decoration, road signs, and in vivo bioimaging [4-6]. For these applications, long persistence times are often desir- able. Two types of active center involved are： emitters and traps in LLP phosphors. Emitters are capable of emitting ra- diation after being excited, and their color is determined by the emission wavelength of the LLP phosphor. Traps states usually do not emit radiation, but store the excitation energy later releasing it to the emitters under thermal disturbance. Thus, traps play an important role in photo-energy storage of LLP phosphors. The trap type and trap distribution are gen- erally associated with lattice defects and/or co-dopants. The overall nature of the trap states determines the persistence in- tensity and time. Thus, design of LLP phosphors focuses on generating suitable trap levels and trap densities.
基金supported by grants from the Hebei Province Natural Science Foundation of China(no.H2019104017)and Special Fund for Team of Sports Induced Heart Injury Prevention and Treatment in Military.
文摘This study was to optimize the exercise preconditioning(EP)intensity in protecting from exhaustive exercise-induced cardiac injury(EECI).A total of 98 male Sprague-Dawley rats were divided into 7 groups(n=14):the control group(C),the exhaustive exercise group(EE)and the EP+EE groups,which include the V10(53.0%VO_(2max)),V15(58.4%VO_(2max)),V20(67.0%VO_(2max)),V26(74.0%VO_(2max))and V30(80.0%VO_(2max))groups.Except the C group,the other groups were subjected to treadmill running.The serum contents of N terminal pro B type natriuretic peptide(NT-proBNP)and cardiac troponin I(cTn-I)were detected by the enzyme-linked immunosorbent assay method,ECG was recorded,heart function was detected by pressure volume catheter and the activities of mitochondrial electron transfer pathway(ET pathway)complexesⅠ,ⅡandⅣwere measured by high-resolution respiration instrument.Compared to the EE group,the EP groups have shown decrease of NT-proBNP and cTn-I,improvement of mitochondrial respiratory function and car-diac function.Compared to other EP groups,the V26 group has shown significant decrease of myocardial enzymes and improvement of mitochondrial function.The correlation analysis showed the EP effect was proportional to EP intensity in the range of 53.0%VO_(2max)-74.0%VO_(2max).High intensity and long duration of exhaustive exercise caused cardiac injury and EP could decrease serum level of NT-proBNP and cTn-I,improve electrical derangement and the left ventricular function,and raise the activities of ET pathway complexesⅠ,ⅡandⅣ.The protection of EP on EECI was improved as the EP intensity was increased from 53.0%VO_(2max)to 74.0%VO_(2max)and when EP intensity was 74.0%VO_(2max),the effect was the most obvious among all the setting EP groups.
基金supported by the National Key Research and Development Program of China(2021YFC2701103,2021YFA0910602,and 2019YFA0802804)the National Natural Science Foundation of China(82070258 and 31925011)+1 种基金Open Research Fund of State Key Laboratory of Genetic Engineering,Fudan University(SKLGE-2104)Science and Technology Research Program of Shanghai(19DZ2282100)。
文摘Many clustered regularly interspaced short palindromic repeat and CRISPR-associated protein 12b(CRISPR-Cas12b)nucleases have been computationally identified,yet their potential for genome editing remains largely unexplored.In this study,we conducted a GFP-activation assay screening 13 Cas12b nucleases for mammalian genome editing,identifying five active candidates.Candidatus hydrogenedentes Cas12b(ChCas12b)was found to recognize a straightforward WTN(W=T or A)proto-spacer adjacent motif(PAM),thereby dramatically expanding the targeting scope.Upon optimization of the single guide RNA(sgRNA)scaffold,ChCas12b exhibited activity comparable to SpCas9 across a panel of nine endogenous loci.Additionally,we identified nine mutations enhancing ChCas12b specificity.More importantly,we demonstrated that both ChCas12b and its high-fidelity variant,ChCas12b-D496A,enabled allelespecific disruption of genes harboring single nucleotide polymorphisms(SNPs).These data position ChCas12b and its high-fidelity counterparts as promising tools for both fundamental research and therapeutic applications.
