One of the main diseases that adversely impacts the global citrus industry is citrus bacterial canker(CBC),caused by the bacteria Xanthomonas citri subsp.citri(Xcc).Response to CBC is a complex process,with both prote...One of the main diseases that adversely impacts the global citrus industry is citrus bacterial canker(CBC),caused by the bacteria Xanthomonas citri subsp.citri(Xcc).Response to CBC is a complex process,with both proteinDNA as well as protein–protein interactions for the regulatory network.To detect such interactions in CBC resistant regulation,a citrus high-throughput screening system with 203 CBC-inducible transcription factors(TFs),were developed.Screening the upstream regulators of target by yeast-one hybrid(Y1H)methods was also performed.A regulatory module of CBC resistance was identified based on this system.One TF(CsDOF5.8)was explored due to its interactions with the 1-kb promoter fragment of CsPrx25,a resistant gene of CBC involved in reactive oxygen species(ROS)homeostasis regulation.Electrophoretic mobility shift assay(EMSA),dual-LUC assays,as well as transient overexpression of CsDOF5.8,further validated the interactions and transcriptional regulation.The CsDOF5.8–CsPrx25 promoter interaction revealed a complex pathway that governs the regulation of CBC resistance via H2O2homeostasis.The high-throughput Y1H/Y2H screening system could be an efficient tool for studying regulatory pathways or network of CBC resistance regulation.In addition,it could highlight the potential of these candidate genes as targets for efforts to breed CBC-resistant citrus varieties.展开更多
Citrus bacterial canker(CBC) is resulted from Xanthomonas citri subsp. citri(Xcc) infection and poses a significant threat to citrus production.Glutathione S-transferases(GSTs) are critical in maintaining redox homeos...Citrus bacterial canker(CBC) is resulted from Xanthomonas citri subsp. citri(Xcc) infection and poses a significant threat to citrus production.Glutathione S-transferases(GSTs) are critical in maintaining redox homeostasis in plants, especially in relation to abiotic and biotic stress responses. However, the function of GSTs in resisting CBC remains unclear. Here, citrus glutathione S-transferases were investigated applying a genome-wide approach. In total, 69 CsGSTs belonging to seven classes were identified, and the phylogeny, chromosomal distribution, gene structures and conserved motifs were analyzed. Several CsGSTs responded to Xcc infection, as observed in the upregulation of CsGSTF1 and CsGSTU18 in the CBC-sensitive ‘Wanjincheng' variety but not in the resistant ‘Kumquat' variety. CsGSTF1 and CsGSTU18 were localized at the cytoplasm. Transient overexpression of CsGSTF1 and CsGSTU18 mediated reactive oxygen species(ROS) scavenging, whereas the virus-induced gene silencing(VIGS) of CsGSTF1 and CsGSTU18 caused strong CBC resistance and ROS burst. The present study investigated the characterization of citrus GST gene family, and discovered that CsGSTF1 and CsGSTU18 negatively contributed to CBC through modulating ROS homeostasis. These findings emphasize the significance of GSTs in infection resistance in plants.展开更多
With continually increasing urbanization,the land cover in urban areas continues to change,resulting in the loss of biodiversity.Birds are highly sensitive to changes in habitat.Most forest birds perch on plants that ...With continually increasing urbanization,the land cover in urban areas continues to change,resulting in the loss of biodiversity.Birds are highly sensitive to changes in habitat.Most forest birds perch on plants that provide increased safety to reduce the risk of predation,and small birds may also consider insulation when using roosting plants in winter because of cold weather.Landscaping plants thus shape the nocturnal roosting environment of urban birds,and proper planting is essential for the survival of birds at night.The use of roosting plants by urban birds should therefore be studied to provide a reference for landscaping.In the current study,we observed 1865 nocturnal roosting birds in Beijing from 2021 to 2022,with 23 species of birds from 12 families and 45 species of plants from 22 families recorded.Juniperus chinensis exhibited the highest bird rarity-weighted richness,followed by Fraxinus pennsylvanica,Phyllostachys propinqua,Pinus tabuliformis,and Ulmus pumila.The diameter at breast height,tree height,and crown width of plants used by birds was largest in summer and smallest in winter,and the perch height of birds was the highest in spring and summer and the lowest in winter.Birds used the highest proportion of deciduous plants in summer and the highest proportion of evergreen plants in winter.A significant seasonal difference in the use of evergreen and deciduous plants by small birds was noted,with a preference for deciduous plants in summer and evergreen plants in winter,while this preference was not found in large birds.These findings indicate that evergreen plants provide a vital nocturnal roosting environment for small birds in winter.To provide a better nocturnal roosting habitat for urban birds,we recommend paying attention to the combination of evergreen and deciduous plants when carrying out landscape construction.展开更多
Background Cognitive-behavioural therapy for insomnia(CBTi)is the first-line treatment for those with this sleep disorder.However,depressive and anxiety symptoms often co-occur with acute insomnia,which may affect the...Background Cognitive-behavioural therapy for insomnia(CBTi)is the first-line treatment for those with this sleep disorder.However,depressive and anxiety symptoms often co-occur with acute insomnia,which may affect the effectiveness of CBTitreatment.Aims This study aimed to determine the impact of depressive and anxiety symptoms on the efficacy of CBTi in treating acute insomnia.Methods A single-arm clinical trial was conducted among individuals who have acute insomnia.Participants underwent self-guided CBTi for 1-week.Their insomnia,depressive symptoms and anxiety symptoms were evaluated using the Insomnia Severity Index and the Hospital Anxiety and Depression Scale at baseline,post-treatment and 3-month follow-up.Repeated measures analysis of variance was used to assess the effectiveness of CBTi in treating insomnia,depressive symptoms and anxiety symptoms.A multivariate Cox regression model was used to determine the impact of depressive and anxiety symptoms on insomnia.Results The study found significant reductions in insomnia,depressive symptoms and anxiety symptoms at both post-treatment and 3-month follow-up(F=17.45,p<0.001;F=36.37,p=0.001;and F=81.51,p<0.001,respectively).The duration of CBTi treatment had a positive impact on insomnia recovery(hazard ratio(HR)=0.94,p=0.018).However,baseline depressive symptoms(HR=1.83,p=0.004)and baseline anxiety symptoms(HR=1.99,p=0.001)had significant negative effects on insomnia recovery.Conclusions The study showed that a 1-week self-guided CBTi treatment is effective in treating acute insomnia and comorbid depressive and anxiety symptoms.However,baseline depressive and anxiety symptoms negatively impact treatment effectiveness.Therefore,clinicians should assess for depressive and anxiety symptoms before treating acute insomnia with monotherapy CBTi.展开更多
Tensile and shear fractures are significant mechanisms for rock failure.Understanding the fractures that occur in rock can reveal rock failure mechanisms.Scanning electron microscopy(SEM)has been widely used to analyz...Tensile and shear fractures are significant mechanisms for rock failure.Understanding the fractures that occur in rock can reveal rock failure mechanisms.Scanning electron microscopy(SEM)has been widely used to analyze tensile and shear fractures of rock on a mesoscopic scale.To quantify tensile and shear fractures,this study proposed an innovative method composed of SEM images and deep learning techniques to identify tensile and shear fractures in red sandstone.First,direct tensile and preset angle shear tests were performed for red sandstone to produce representative tensile and shear fracture surfaces,which were then observed by SEM.Second,these obtained SEM images were applied to develop deep learning models(AlexNet,VGG13,and SqueezeNet).Model evaluation showed that VGG13 was the best model,with a testing accuracy of 0.985.Third,the features of tensile and shear fractures of red sandstone learned by VGG13 were analyzed by the integrated gradient algorithm.VGG13 was then implemented to identify the distribution and proportion of tensile and shear fractures on the failure surfaces of rock fragments caused by uniaxial compression and Brazilian splitting tests.Results demonstrated the model feasibility and suggested that the proposed method can reveal rock failure mechanisms.展开更多
As the bacterial etiologic agent causing citrus bacterial canker(CBC),Xanthomonas citri subsp.citri(Xcc)seriously impacts citrus plantation and fruit production globally.In an earlier study,we demonstrated that CsBZIP...As the bacterial etiologic agent causing citrus bacterial canker(CBC),Xanthomonas citri subsp.citri(Xcc)seriously impacts citrus plantation and fruit production globally.In an earlier study,we demonstrated that CsBZIP40 can positively impact CBC resistance in the sweet orange(Citrus sinensis).However,the mechanistic basis for the protective benefits conferred by CsBZIP40 is yet to be delineated.Here,we show that CsBZIP40 positively regulates CBC resistance and reactive oxygen species(ROS)homeostasis in transgenic sweet orange overexpressing CsBZIP40.CsBZIP40 directly binds to the TGA-box of the CsWRKY43 promoter to repress its transcriptional activity.CsWRKY43 overexpression induces CBC susceptibility in transgenic sweet oranges.In contrast,its inhibition produces strong resistance to CBC.CsWRKY43 directly binds to the W-boxes of the CsPrx53 and CsSOD13 promoters to positively regulate the activities of these antioxidant enzymes,resulting in the negative regulation of ROS homeostasis and CBC resistance in sweet orange plants.CsPrx53/CsSOD13 knockdown enhances ROS accumulation and CBC resistance.Overall,our results outline a regulatory pathway through which CsBZIP40 transcriptionally represses CsWRKY43-CsPrx53/CsSOD13 cascade-mediated ROS scavenging in a manner conducive to CBC resistance.These mechanisms underscore the potential importance of CsBZIP40,CsWRKY43,CsPrx53,and CsSOD13,providing promising strategies for the prevention of CBC.展开更多
Three-dimensionally ordered macroporous(3DOM)perovskite materials have attracted the interest from researchers worldwide due to their unique macroporous structure,flexible composition,tailorable physicochemical proper...Three-dimensionally ordered macroporous(3DOM)perovskite materials have attracted the interest from researchers worldwide due to their unique macroporous structure,flexible composition,tailorable physicochemical property,high stability and biocompatibility.In particular,they were widely used in environmental field,such as photocatalysis,catalytic combustion,catalytic oxidation and sensors.In this review,the recent progresses in the synthesis of 3DOM perovskite materials and their environmental applications are summarized.The advantages and the promoting mechanisms of 3DOM perovskite materials for different applications are discussed in detail.Subsequently,the challenges and perspectives on the topic are proposed.展开更多
A solvent-assisted methodology has been developed to synthesize CH_3NH_3 PbI_3perovskite absorber layers.It involved the use of a mixed solvent of CH_3NH_3 I,PbI_2,c-butyrolactone,and dimethyl sulfoxide(DMSO) followed...A solvent-assisted methodology has been developed to synthesize CH_3NH_3 PbI_3perovskite absorber layers.It involved the use of a mixed solvent of CH_3NH_3 I,PbI_2,c-butyrolactone,and dimethyl sulfoxide(DMSO) followed by the addition of chlorobenzene(CB).The method produced ultra-flat and dense perovskite capping layers atop mesoporous TiO_2 films,enabling a remarkable improvement in the performance of free hole transport material(HTM) carbon electrode-based perovskite solar cells(PSCs).Toluene(TO) was also studied as an additional solvent for comparison.At the annealing temperature of 100 °C,the fabricated HTM-free PSCs based on drop-casting CB demonstrated power conversion efficiency(PCE) of 9.73 %,which is 36 and 71 % higher than those fabricated from the perovskite films using TO or without adding an extra solvent,respectively.The interaction between the PbI_2–DMSO–CH_3NH_3I intermediate phase and the additional solvent was discussed.Furthermore,the influence of the annealing temperature on the absorber film formation,morphology,and crystalline structure was investigated and correlated with the photovoltaic performance.Highly efficient,simple,and stable HTM-free solar cells with a PCE of 11.44 % were prepared utilizing the optimum perovskite absorbers annealed at 120 °C.展开更多
Using four satellite data sets(TOMS/SBUV, OMI, MLS, and HALOE), we analyze the seasonal variations of the total column ozone(TCO) and its zonal deviation(TCO*), and reveal the vertical structure of the Ozone Low(OV) o...Using four satellite data sets(TOMS/SBUV, OMI, MLS, and HALOE), we analyze the seasonal variations of the total column ozone(TCO) and its zonal deviation(TCO*), and reveal the vertical structure of the Ozone Low(OV) over the Asian continent. Our principal findings are:(1) The TCO over the Asian continent reaches its maximum in the spring and its minimum in the autumn. The Ozone Low exists from May to September.(2) The Ozone Low has two negative cores, located in the lower and the upper stratosphere. The lower core is near 30 hPa in the winter and 70 hPa in the other seasons. The upper core varies from 10 hPa to 1 hPa among the four seasons.(3)The position of the Ozone Low in the lower and the upper stratosphere over the Asian continent shows seasonal variability.展开更多
Intrusion detection aims to detect intrusion behavior and serves as a complement to firewalls.It can detect attack types of malicious network communications and computer usage that cannot be detected by idiomatic fire...Intrusion detection aims to detect intrusion behavior and serves as a complement to firewalls.It can detect attack types of malicious network communications and computer usage that cannot be detected by idiomatic firewalls.Many intrusion detection methods are processed through machine learning.Previous literature has shown that the performance of an intrusion detection method based on hybrid learning or integration approach is superior to that of single learning technology.However,almost no studies focus on how additional representative and concise features can be extracted to process effective intrusion detection among massive and complicated data.In this paper,a new hybrid learning method is proposed on the basis of features such as density,cluster centers,and nearest neighbors(DCNN).In this algorithm,data is represented by the local density of each sample point and the sum of distances from each sample point to cluster centers and to its nearest neighbor.k-NN classifier is adopted to classify the new feature vectors.Our experiment shows that DCNN,which combines K-means,clustering-based density,and k-NN classifier,is effective in intrusion detection.展开更多
The volume of trajectory data has become tremendously huge in recent years. How to effectively and efficiently maintain and compute such trajectory data has become a challenging task. In this paper, we propose a traje...The volume of trajectory data has become tremendously huge in recent years. How to effectively and efficiently maintain and compute such trajectory data has become a challenging task. In this paper, we propose a trajectory spatial and temporal compression framework, namely CLEAN. The key of spatial compression is to mine meaningful trajectory frequent patterns on road network. By treating the mined patterns as dictionary items, the long trajectories have the chance to be encoded by shorter paths, thus leading to smaller space cost. And an error-bounded temporal compression is carefully designed on top of the identified spatial patterns for much low space cost. Meanwhile, the patterns are also utilized to improve the performance of two trajectory applications, range query and clustering, without decompression overhead. Extensive experiments on real trajectory datasets validate that CLEAN significantly outperforms existing state-of-art approaches in terms of spatial-temporal compression and trajectory applications.展开更多
The problem of colority control of printing and dyeing wastewater has become a technical problem that plagues related companies.Bentonite is an adsorbent with excellent properties.Modification of bentonite with enviro...The problem of colority control of printing and dyeing wastewater has become a technical problem that plagues related companies.Bentonite is an adsorbent with excellent properties.Modification of bentonite with environmentally friendly substances can improve its decolorization performance.In this experiment,the simulated printing and dyeing wastewater was taken as the control object,and the bentonite was modified with environmentally friendly materials such as sodium carboxymethyl cellulose(CMC)and lignin to prepare a new modified bentonite;then the modified bentonite was used to adsorb the simulated wastewater to reduce the water colority and COD;finally the relevant design of the adsorption process was made.Results indicate that M lignin∶M CMC∶M original bentonite=1∶2∶97 had the optimum treatment effect,the optimum modification temperature was 30℃ and the modification time was 4 h;the optimum conditions for the adsorption process were:pH=5,temperature=30℃,reaction time=60 min,dosage=0.05 g of modified bentonite/mL simulated dye solution.The final removal rate of colority and COD reached 95.0% and 98.2%,respectively.Compared with the original bentonite,this new modified bentonite has greater adsorption capacity and thus has greater application value.展开更多
Piles are the main building foundation in permafrost regions. Thawing the permafrost foundation would have a negative effect on a pile, and may cause damage to the building. This paper focuses on the effects of negati...Piles are the main building foundation in permafrost regions. Thawing the permafrost foundation would have a negative effect on a pile, and may cause damage to the building. This paper focuses on the effects of negative friction force due to the melt of permafrost, and presents four calculated methods for bearing capacity of a pile. An engineering station was taken as an example, where the lengths of a pile were compared based on four methods. Finally, quick field load tests were carried out, and some meaningful conclusions are presented. Thus, these analytical results can be used to design a pile for permafrost regions.展开更多
The content of Cu,Zn in the sediments from coastal wetlands of the Yellow River Delta was determined.The results showed that:(i)The content of Cu,Zn range was 16.70-50.40 mg/kg,18.15-48.80 mg/kg,respectively.The mean ...The content of Cu,Zn in the sediments from coastal wetlands of the Yellow River Delta was determined.The results showed that:(i)The content of Cu,Zn range was 16.70-50.40 mg/kg,18.15-48.80 mg/kg,respectively.The mean content of Cu,Zn was 31.12mg/kg,36.74 mg/kg,respectively.Compared with the soil environmental background values of Shandong Province,the content of Cu was excessive,while the content of Zn was below the background.(ii)The concentrations of Cu,Zn in sediment in the coast of the Yellow River Delta were higher than in the other two areas.(iii)Vertical distribution characteristics of the concentrations of Cu,Zn were increasing with depth.The maximum content of Cu,Zn was 80-100 cm,in general,the content of Cu,Zn in the bottom sediments was higher than that in the surface sediments.The growth and decline trends of Zn in Tamarix and Suaeda areas were much the same and all higher than in the Phragmites communis area.(iv)The distribution characteristics of Cu concentration in different vegetation cover in sediment is Suaeda>Phragmites communis>Tamarix,which reflected different effects on retention of Cu in the sediments because of the different vegetation types.The highest content of Zn in the 0-20 cm sediments in Tamarix area was 44.07 mg/kg.展开更多
Microcombs have enabled a host of cutting-edge applications from metrology to communications that have garnered significant attention in the last decade.Nevertheless,due to the thermal instability of the microresonato...Microcombs have enabled a host of cutting-edge applications from metrology to communications that have garnered significant attention in the last decade.Nevertheless,due to the thermal instability of the microresonator,additional control devices like auxiliary lasers are indispensable for single-soliton generation in some scenarios.Specifically,the increased system complexity would be too overwhelming for dual-microcomb generation.Here,we put forward a novel approach to mitigate the thermal instability and generate the dual-microcomb using a compact system.This process is akin to mode-division multiplexing,as the dual-microcombs are generated by pumping the dual-mode of a single Si_(3)N_(4) microresonator with a continuous-wave laser.Both numerical simulations and experimental measurements indicate that this innovative technique could offer a straightforward way to enlarge the soliton existence range,allowing entry into the multistability regime and triggering another microcomb alongside the main soliton pulse.This outcome not only shines new light on the interaction mechanism of microresonator modes but also provides an avenue for the development of dual-microcomb-based ranging and low phase noise microwave generation.展开更多
Particle segregation and mixing behavior play a crucial role in industrial processes.This study investigates the saturated jetsam fraction,which indicates the maximum capacity of flotsam to entrain jetsam,in an initia...Particle segregation and mixing behavior play a crucial role in industrial processes.This study investigates the saturated jetsam fraction,which indicates the maximum capacity of flotsam to entrain jetsam,in an initially separated binary fluidized bed with particle size differences.According to the value of saturated jetsam fraction,three distinct regimes-segregation,mixing,and an intermediate regime-are identified.Moreover,intriguing relationships between the saturated jetsam fraction and superficial gas velocity are observed,exhibiting monotonic trends in both the segregation and mixing regimes,while a unique volcano-shaped curve in the intermediate regime.Additionally,a comprehensive entrainment model based on two-fluid model elucidates the observed phenomena,emphasizing the significance of mixing behavior in fluidized layer on the saturated jetsam fraction.This work offers potential insights for evaluating segregation in industrial applications.展开更多
The optical frequency comb has attracted considerable interest due to its diverse applications in optical atomic clocks,ultra-low-noise microwave generation,dual-comb spectroscopy,and optical communications.The merits...The optical frequency comb has attracted considerable interest due to its diverse applications in optical atomic clocks,ultra-low-noise microwave generation,dual-comb spectroscopy,and optical communications.The merits of large frequency spacing,high integration,and low power consumption have shown that microresonator-based Kerr optical frequency combs will become mainstream in the future.Two methods of pump frequency tuning and self-injection locking were used to obtain Kerr combs in the same silicon nitride microresonators with free spectral ranges of 50 GHz and 100 GHz.Singlesoliton combs are realized with both methods.Simplicity,pump power,spectrum bandwidth,conversion efficiency,and linewidth are compared and analyzed.Our results show that the advantages of pump frequency tuning are a wider spectrum and higher soliton power while the advantages of self-injection locking are simplicity,compactness,low cost,significant linewidth narrowing,and high conversion efficiency.展开更多
基金funded by the National Key Research and Development Program of China(2022YFD1201600)the earmarked fund for the China Agriculture Research System(CARS-26)+1 种基金the Fundamental Research Funds for the Central Universities,China(SWU-XDJH202308)the Science and Technology Research Program of Chongqing Municipal Education Commission,China(KJQN202001418)。
文摘One of the main diseases that adversely impacts the global citrus industry is citrus bacterial canker(CBC),caused by the bacteria Xanthomonas citri subsp.citri(Xcc).Response to CBC is a complex process,with both proteinDNA as well as protein–protein interactions for the regulatory network.To detect such interactions in CBC resistant regulation,a citrus high-throughput screening system with 203 CBC-inducible transcription factors(TFs),were developed.Screening the upstream regulators of target by yeast-one hybrid(Y1H)methods was also performed.A regulatory module of CBC resistance was identified based on this system.One TF(CsDOF5.8)was explored due to its interactions with the 1-kb promoter fragment of CsPrx25,a resistant gene of CBC involved in reactive oxygen species(ROS)homeostasis regulation.Electrophoretic mobility shift assay(EMSA),dual-LUC assays,as well as transient overexpression of CsDOF5.8,further validated the interactions and transcriptional regulation.The CsDOF5.8–CsPrx25 promoter interaction revealed a complex pathway that governs the regulation of CBC resistance via H2O2homeostasis.The high-throughput Y1H/Y2H screening system could be an efficient tool for studying regulatory pathways or network of CBC resistance regulation.In addition,it could highlight the potential of these candidate genes as targets for efforts to breed CBC-resistant citrus varieties.
基金funded by the National Key Research and Development Program of China (Grant No.2022YFD1201600)Natural Science Foundation of Chongqing (Grant No.cstc2020jcyj-msxmX1064)+1 种基金Earmarked Funds for the China Agriculture Research System (Grant No.CARS-26)Three-year Action Plan of Xi'an University (Grant No.2021XDJH41)。
文摘Citrus bacterial canker(CBC) is resulted from Xanthomonas citri subsp. citri(Xcc) infection and poses a significant threat to citrus production.Glutathione S-transferases(GSTs) are critical in maintaining redox homeostasis in plants, especially in relation to abiotic and biotic stress responses. However, the function of GSTs in resisting CBC remains unclear. Here, citrus glutathione S-transferases were investigated applying a genome-wide approach. In total, 69 CsGSTs belonging to seven classes were identified, and the phylogeny, chromosomal distribution, gene structures and conserved motifs were analyzed. Several CsGSTs responded to Xcc infection, as observed in the upregulation of CsGSTF1 and CsGSTU18 in the CBC-sensitive ‘Wanjincheng' variety but not in the resistant ‘Kumquat' variety. CsGSTF1 and CsGSTU18 were localized at the cytoplasm. Transient overexpression of CsGSTF1 and CsGSTU18 mediated reactive oxygen species(ROS) scavenging, whereas the virus-induced gene silencing(VIGS) of CsGSTF1 and CsGSTU18 caused strong CBC resistance and ROS burst. The present study investigated the characterization of citrus GST gene family, and discovered that CsGSTF1 and CsGSTU18 negatively contributed to CBC through modulating ROS homeostasis. These findings emphasize the significance of GSTs in infection resistance in plants.
基金supported by the Beijing Municipal Commission of Science and Technology(No.D171100007217002).
文摘With continually increasing urbanization,the land cover in urban areas continues to change,resulting in the loss of biodiversity.Birds are highly sensitive to changes in habitat.Most forest birds perch on plants that provide increased safety to reduce the risk of predation,and small birds may also consider insulation when using roosting plants in winter because of cold weather.Landscaping plants thus shape the nocturnal roosting environment of urban birds,and proper planting is essential for the survival of birds at night.The use of roosting plants by urban birds should therefore be studied to provide a reference for landscaping.In the current study,we observed 1865 nocturnal roosting birds in Beijing from 2021 to 2022,with 23 species of birds from 12 families and 45 species of plants from 22 families recorded.Juniperus chinensis exhibited the highest bird rarity-weighted richness,followed by Fraxinus pennsylvanica,Phyllostachys propinqua,Pinus tabuliformis,and Ulmus pumila.The diameter at breast height,tree height,and crown width of plants used by birds was largest in summer and smallest in winter,and the perch height of birds was the highest in spring and summer and the lowest in winter.Birds used the highest proportion of deciduous plants in summer and the highest proportion of evergreen plants in winter.A significant seasonal difference in the use of evergreen and deciduous plants by small birds was noted,with a preference for deciduous plants in summer and evergreen plants in winter,while this preference was not found in large birds.These findings indicate that evergreen plants provide a vital nocturnal roosting environment for small birds in winter.To provide a better nocturnal roosting habitat for urban birds,we recommend paying attention to the combination of evergreen and deciduous plants when carrying out landscape construction.
基金supported by the National Key R&D Program of China(BZ:grant number 2021YFC2501500)the Basic and Applied Basic Research Project of Guangzhou Basic Research Program(CZ:grant number 202201011502)+2 种基金the National Natural Science Foundation of China(BZ:grant number 82271525)Nanfang Hospital Clinical Research Project of Southern Medical University(BZ:grant number 2021CR009)the Education Research Projects of Nanfang Hospital(BZ:grant number 21NJ-ZDPY01).
文摘Background Cognitive-behavioural therapy for insomnia(CBTi)is the first-line treatment for those with this sleep disorder.However,depressive and anxiety symptoms often co-occur with acute insomnia,which may affect the effectiveness of CBTitreatment.Aims This study aimed to determine the impact of depressive and anxiety symptoms on the efficacy of CBTi in treating acute insomnia.Methods A single-arm clinical trial was conducted among individuals who have acute insomnia.Participants underwent self-guided CBTi for 1-week.Their insomnia,depressive symptoms and anxiety symptoms were evaluated using the Insomnia Severity Index and the Hospital Anxiety and Depression Scale at baseline,post-treatment and 3-month follow-up.Repeated measures analysis of variance was used to assess the effectiveness of CBTi in treating insomnia,depressive symptoms and anxiety symptoms.A multivariate Cox regression model was used to determine the impact of depressive and anxiety symptoms on insomnia.Results The study found significant reductions in insomnia,depressive symptoms and anxiety symptoms at both post-treatment and 3-month follow-up(F=17.45,p<0.001;F=36.37,p=0.001;and F=81.51,p<0.001,respectively).The duration of CBTi treatment had a positive impact on insomnia recovery(hazard ratio(HR)=0.94,p=0.018).However,baseline depressive symptoms(HR=1.83,p=0.004)and baseline anxiety symptoms(HR=1.99,p=0.001)had significant negative effects on insomnia recovery.Conclusions The study showed that a 1-week self-guided CBTi treatment is effective in treating acute insomnia and comorbid depressive and anxiety symptoms.However,baseline depressive and anxiety symptoms negatively impact treatment effectiveness.Therefore,clinicians should assess for depressive and anxiety symptoms before treating acute insomnia with monotherapy CBTi.
基金financially supported by the National Natural Science Foundation of China(No.52074349)the Fundamental Research Funds for the Central Universities of Central South University(No.2023zzts0726)。
文摘Tensile and shear fractures are significant mechanisms for rock failure.Understanding the fractures that occur in rock can reveal rock failure mechanisms.Scanning electron microscopy(SEM)has been widely used to analyze tensile and shear fractures of rock on a mesoscopic scale.To quantify tensile and shear fractures,this study proposed an innovative method composed of SEM images and deep learning techniques to identify tensile and shear fractures in red sandstone.First,direct tensile and preset angle shear tests were performed for red sandstone to produce representative tensile and shear fracture surfaces,which were then observed by SEM.Second,these obtained SEM images were applied to develop deep learning models(AlexNet,VGG13,and SqueezeNet).Model evaluation showed that VGG13 was the best model,with a testing accuracy of 0.985.Third,the features of tensile and shear fractures of red sandstone learned by VGG13 were analyzed by the integrated gradient algorithm.VGG13 was then implemented to identify the distribution and proportion of tensile and shear fractures on the failure surfaces of rock fragments caused by uniaxial compression and Brazilian splitting tests.Results demonstrated the model feasibility and suggested that the proposed method can reveal rock failure mechanisms.
基金This study was funded by the National Key Research and Development Program of China(2022YFD1201600,2021YFD1600800)National Natural Sciences Foundation of China(32202425)Earmarked Funds for the China Agriculture Research System(CARS-26).
文摘As the bacterial etiologic agent causing citrus bacterial canker(CBC),Xanthomonas citri subsp.citri(Xcc)seriously impacts citrus plantation and fruit production globally.In an earlier study,we demonstrated that CsBZIP40 can positively impact CBC resistance in the sweet orange(Citrus sinensis).However,the mechanistic basis for the protective benefits conferred by CsBZIP40 is yet to be delineated.Here,we show that CsBZIP40 positively regulates CBC resistance and reactive oxygen species(ROS)homeostasis in transgenic sweet orange overexpressing CsBZIP40.CsBZIP40 directly binds to the TGA-box of the CsWRKY43 promoter to repress its transcriptional activity.CsWRKY43 overexpression induces CBC susceptibility in transgenic sweet oranges.In contrast,its inhibition produces strong resistance to CBC.CsWRKY43 directly binds to the W-boxes of the CsPrx53 and CsSOD13 promoters to positively regulate the activities of these antioxidant enzymes,resulting in the negative regulation of ROS homeostasis and CBC resistance in sweet orange plants.CsPrx53/CsSOD13 knockdown enhances ROS accumulation and CBC resistance.Overall,our results outline a regulatory pathway through which CsBZIP40 transcriptionally represses CsWRKY43-CsPrx53/CsSOD13 cascade-mediated ROS scavenging in a manner conducive to CBC resistance.These mechanisms underscore the potential importance of CsBZIP40,CsWRKY43,CsPrx53,and CsSOD13,providing promising strategies for the prevention of CBC.
基金supported by the Tianjin Municipal Natural Science Foundation(17JCYBJC22600)the Fundamental Research Funds for the Central Universities~~
文摘Three-dimensionally ordered macroporous(3DOM)perovskite materials have attracted the interest from researchers worldwide due to their unique macroporous structure,flexible composition,tailorable physicochemical property,high stability and biocompatibility.In particular,they were widely used in environmental field,such as photocatalysis,catalytic combustion,catalytic oxidation and sensors.In this review,the recent progresses in the synthesis of 3DOM perovskite materials and their environmental applications are summarized.The advantages and the promoting mechanisms of 3DOM perovskite materials for different applications are discussed in detail.Subsequently,the challenges and perspectives on the topic are proposed.
基金supported by the National Natural Science Foundation of China(Nos.11274119,61275038)
文摘A solvent-assisted methodology has been developed to synthesize CH_3NH_3 PbI_3perovskite absorber layers.It involved the use of a mixed solvent of CH_3NH_3 I,PbI_2,c-butyrolactone,and dimethyl sulfoxide(DMSO) followed by the addition of chlorobenzene(CB).The method produced ultra-flat and dense perovskite capping layers atop mesoporous TiO_2 films,enabling a remarkable improvement in the performance of free hole transport material(HTM) carbon electrode-based perovskite solar cells(PSCs).Toluene(TO) was also studied as an additional solvent for comparison.At the annealing temperature of 100 °C,the fabricated HTM-free PSCs based on drop-casting CB demonstrated power conversion efficiency(PCE) of 9.73 %,which is 36 and 71 % higher than those fabricated from the perovskite films using TO or without adding an extra solvent,respectively.The interaction between the PbI_2–DMSO–CH_3NH_3I intermediate phase and the additional solvent was discussed.Furthermore,the influence of the annealing temperature on the absorber film formation,morphology,and crystalline structure was investigated and correlated with the photovoltaic performance.Highly efficient,simple,and stable HTM-free solar cells with a PCE of 11.44 % were prepared utilizing the optimum perovskite absorbers annealed at 120 °C.
基金funded by the National Science Foundation of China (91537213, 91837311, 41675039, 41875048)
文摘Using four satellite data sets(TOMS/SBUV, OMI, MLS, and HALOE), we analyze the seasonal variations of the total column ozone(TCO) and its zonal deviation(TCO*), and reveal the vertical structure of the Ozone Low(OV) over the Asian continent. Our principal findings are:(1) The TCO over the Asian continent reaches its maximum in the spring and its minimum in the autumn. The Ozone Low exists from May to September.(2) The Ozone Low has two negative cores, located in the lower and the upper stratosphere. The lower core is near 30 hPa in the winter and 70 hPa in the other seasons. The upper core varies from 10 hPa to 1 hPa among the four seasons.(3)The position of the Ozone Low in the lower and the upper stratosphere over the Asian continent shows seasonal variability.
文摘Intrusion detection aims to detect intrusion behavior and serves as a complement to firewalls.It can detect attack types of malicious network communications and computer usage that cannot be detected by idiomatic firewalls.Many intrusion detection methods are processed through machine learning.Previous literature has shown that the performance of an intrusion detection method based on hybrid learning or integration approach is superior to that of single learning technology.However,almost no studies focus on how additional representative and concise features can be extracted to process effective intrusion detection among massive and complicated data.In this paper,a new hybrid learning method is proposed on the basis of features such as density,cluster centers,and nearest neighbors(DCNN).In this algorithm,data is represented by the local density of each sample point and the sum of distances from each sample point to cluster centers and to its nearest neighbor.k-NN classifier is adopted to classify the new feature vectors.Our experiment shows that DCNN,which combines K-means,clustering-based density,and k-NN classifier,is effective in intrusion detection.
基金National Natural Science Foundation of China (Grant No. 61772371,No. 61972286)
文摘The volume of trajectory data has become tremendously huge in recent years. How to effectively and efficiently maintain and compute such trajectory data has become a challenging task. In this paper, we propose a trajectory spatial and temporal compression framework, namely CLEAN. The key of spatial compression is to mine meaningful trajectory frequent patterns on road network. By treating the mined patterns as dictionary items, the long trajectories have the chance to be encoded by shorter paths, thus leading to smaller space cost. And an error-bounded temporal compression is carefully designed on top of the identified spatial patterns for much low space cost. Meanwhile, the patterns are also utilized to improve the performance of two trajectory applications, range query and clustering, without decompression overhead. Extensive experiments on real trajectory datasets validate that CLEAN significantly outperforms existing state-of-art approaches in terms of spatial-temporal compression and trajectory applications.
基金Supported by Project of Shandong Province Natural Science Foundation of China(ZR2015PC022&BS2014HZ011)
文摘The problem of colority control of printing and dyeing wastewater has become a technical problem that plagues related companies.Bentonite is an adsorbent with excellent properties.Modification of bentonite with environmentally friendly substances can improve its decolorization performance.In this experiment,the simulated printing and dyeing wastewater was taken as the control object,and the bentonite was modified with environmentally friendly materials such as sodium carboxymethyl cellulose(CMC)and lignin to prepare a new modified bentonite;then the modified bentonite was used to adsorb the simulated wastewater to reduce the water colority and COD;finally the relevant design of the adsorption process was made.Results indicate that M lignin∶M CMC∶M original bentonite=1∶2∶97 had the optimum treatment effect,the optimum modification temperature was 30℃ and the modification time was 4 h;the optimum conditions for the adsorption process were:pH=5,temperature=30℃,reaction time=60 min,dosage=0.05 g of modified bentonite/mL simulated dye solution.The final removal rate of colority and COD reached 95.0% and 98.2%,respectively.Compared with the original bentonite,this new modified bentonite has greater adsorption capacity and thus has greater application value.
基金supported by the Guangxi Natural Science Foundation(No.2018GXNSFAA281123)Key Laboratory of Early Prevention and Treatment for Regional High Frequency Tumor,Ministry of Education(No.GJZ201604,No.GKE2017-ZZ03)Research Project of Guangxi Health and Family Planning Commission(No.Z20180978)。
文摘Piles are the main building foundation in permafrost regions. Thawing the permafrost foundation would have a negative effect on a pile, and may cause damage to the building. This paper focuses on the effects of negative friction force due to the melt of permafrost, and presents four calculated methods for bearing capacity of a pile. An engineering station was taken as an example, where the lengths of a pile were compared based on four methods. Finally, quick field load tests were carried out, and some meaningful conclusions are presented. Thus, these analytical results can be used to design a pile for permafrost regions.
基金Supported by Experimental Technology Project of Binzhou University(BZXYSYXM201706)Dr.Start Funding Project of Binzhou University(2016Y33)
文摘The content of Cu,Zn in the sediments from coastal wetlands of the Yellow River Delta was determined.The results showed that:(i)The content of Cu,Zn range was 16.70-50.40 mg/kg,18.15-48.80 mg/kg,respectively.The mean content of Cu,Zn was 31.12mg/kg,36.74 mg/kg,respectively.Compared with the soil environmental background values of Shandong Province,the content of Cu was excessive,while the content of Zn was below the background.(ii)The concentrations of Cu,Zn in sediment in the coast of the Yellow River Delta were higher than in the other two areas.(iii)Vertical distribution characteristics of the concentrations of Cu,Zn were increasing with depth.The maximum content of Cu,Zn was 80-100 cm,in general,the content of Cu,Zn in the bottom sediments was higher than that in the surface sediments.The growth and decline trends of Zn in Tamarix and Suaeda areas were much the same and all higher than in the Phragmites communis area.(iv)The distribution characteristics of Cu concentration in different vegetation cover in sediment is Suaeda>Phragmites communis>Tamarix,which reflected different effects on retention of Cu in the sediments because of the different vegetation types.The highest content of Zn in the 0-20 cm sediments in Tamarix area was 44.07 mg/kg.
基金National Key Research and Development Program of China (2020YFB2205804)National Natural Science Foundation of China (62075240)Postgraduate Scientific Research Innovation Project of Hunan Province(CX20210004)。
文摘Microcombs have enabled a host of cutting-edge applications from metrology to communications that have garnered significant attention in the last decade.Nevertheless,due to the thermal instability of the microresonator,additional control devices like auxiliary lasers are indispensable for single-soliton generation in some scenarios.Specifically,the increased system complexity would be too overwhelming for dual-microcomb generation.Here,we put forward a novel approach to mitigate the thermal instability and generate the dual-microcomb using a compact system.This process is akin to mode-division multiplexing,as the dual-microcombs are generated by pumping the dual-mode of a single Si_(3)N_(4) microresonator with a continuous-wave laser.Both numerical simulations and experimental measurements indicate that this innovative technique could offer a straightforward way to enlarge the soliton existence range,allowing entry into the multistability regime and triggering another microcomb alongside the main soliton pulse.This outcome not only shines new light on the interaction mechanism of microresonator modes but also provides an avenue for the development of dual-microcomb-based ranging and low phase noise microwave generation.
基金support from the National Natural Science Foundation of China (Grant Nos.22308187,22208186,22278238,and 22238004)the Beijing Nova Program (Grant No.2022118)the Key Research and Development Program of Inner Mongolia and Ordos,and the Ordos-Tsinghua Innovative&Collaborative Research Program in Carbon Neutrality (Ordos Laboratory).
文摘Particle segregation and mixing behavior play a crucial role in industrial processes.This study investigates the saturated jetsam fraction,which indicates the maximum capacity of flotsam to entrain jetsam,in an initially separated binary fluidized bed with particle size differences.According to the value of saturated jetsam fraction,three distinct regimes-segregation,mixing,and an intermediate regime-are identified.Moreover,intriguing relationships between the saturated jetsam fraction and superficial gas velocity are observed,exhibiting monotonic trends in both the segregation and mixing regimes,while a unique volcano-shaped curve in the intermediate regime.Additionally,a comprehensive entrainment model based on two-fluid model elucidates the observed phenomena,emphasizing the significance of mixing behavior in fluidized layer on the saturated jetsam fraction.This work offers potential insights for evaluating segregation in industrial applications.
基金supported by the National Key R&D Program of China(No.2020YFB2205804)the National Natural Science Foundation of China(No.62075240)。
文摘The optical frequency comb has attracted considerable interest due to its diverse applications in optical atomic clocks,ultra-low-noise microwave generation,dual-comb spectroscopy,and optical communications.The merits of large frequency spacing,high integration,and low power consumption have shown that microresonator-based Kerr optical frequency combs will become mainstream in the future.Two methods of pump frequency tuning and self-injection locking were used to obtain Kerr combs in the same silicon nitride microresonators with free spectral ranges of 50 GHz and 100 GHz.Singlesoliton combs are realized with both methods.Simplicity,pump power,spectrum bandwidth,conversion efficiency,and linewidth are compared and analyzed.Our results show that the advantages of pump frequency tuning are a wider spectrum and higher soliton power while the advantages of self-injection locking are simplicity,compactness,low cost,significant linewidth narrowing,and high conversion efficiency.