[Objectives]This study was conducted to investigate the control effects of silicon fertilizer on growth of kohlrabi(Brassica oleracea L.var.caulorapa DC.)and Plutella xylostella.[Methods]Yougui and Guishen were select...[Objectives]This study was conducted to investigate the control effects of silicon fertilizer on growth of kohlrabi(Brassica oleracea L.var.caulorapa DC.)and Plutella xylostella.[Methods]Yougui and Guishen were selected and sprayed onto kohlrabi for 1,2 and 3 times,forming difference treatments.[Results]Spraying the two kinds of silicon fertilizers for different times promoted the growth of leaf length,leaf width and leaf thickness of kohlrabi,improved chlorophyll contents in kohlrabi leaves and corm yield,and adversely affected P.xylostella.Furthermore,higher treatment times led to a more remarkably effect and higher harm to P.xylostella.[Conclusions]In production,spraying silicon fertilizer onto maize for 2-3 times could realize the purposes of improving kohlrabi yield and alleviating damage by P.xylostella.展开更多
There is a high demand for bespoke grafts to replace damaged or malformed bone and cartilage tissue.Three-dimensional(3D)printing offers a method of fabricating complex anatomical features of clinically relevant sizes...There is a high demand for bespoke grafts to replace damaged or malformed bone and cartilage tissue.Three-dimensional(3D)printing offers a method of fabricating complex anatomical features of clinically relevant sizes.However,the construction of a scaffold to replicate the complex hierarchical structure of natural tissues remains challenging.This paper reports a novel biofabrication method that is capable of creating intricately designed structures of anatomically relevant dimensions.The beneficial properties of the electrospun fibre meshes can finally be realised in 3D rather than the current promising breakthroughs in two-dimensional(2D).The 3D model was created from commercially available computer-aided design software packages in order to slice the model down into many layers of slices,which were arrayed.These 2D slices with each layer of a defined pattern were laser cut,and then successfully assembled with varying thicknesses of 100μm or 200μm.It is demonstrated in this study that this new biofabrication technique can be used to reproduce very complex computer-aided design models into hierarchical constructs with micro and nano resolutions,where the clinically relevant sizes ranging from a simple cube of 20 mm dimension,to a more complex,50 mm-tall human ears were created.In-vitro cell-contact studies were also carried out to investigate the biocompatibility of this hierarchal structure.The cell viability on a micromachined electrospun polylactic-co-glycolic acid fibre mesh slice,where a range of hole diameters from 200μm to 500μm were laser cut in an array where cell confluence values of at least 85%were found at three weeks.Cells were also seeded onto a simpler stacked construct,albeit made with micromachined poly fibre mesh,where cells can be found to migrate through the stack better with collagen as bioadhesives.This new method for biofabricating hierarchical constructs can be further developed for tissue repair applications such as maxillofacial bone injury or nose/ear cartilage replacement in the future.展开更多
Fireworks burning releases massive fine particles and gaseous pollutants, significantly deteriorating air quality during Chinese Lunar New Year (LNY) period. To investigate the impact of the fireworks burning on the...Fireworks burning releases massive fine particles and gaseous pollutants, significantly deteriorating air quality during Chinese Lunar New Year (LNY) period. To investigate the impact of the fireworks burning on the atmospheric aerosol chemistry, 1-hr time resolution of PM2.5 samples in Xi'an during the winter of 2016 including the LNY were collected and detected for inorganic ions, acidity and liquid water content (LWC) of the fine aerosols. PM2.5 during the LNY was 167 ± 87 μg/m^3, two times higher than the China National Ambient Air Quality Standard (75 μg/m^3). K^+ (28 wt.% of the total ion mass) was the most abundant ion in the LNY period, followed by SO^2-4 (25 wt.%) and C1^- (18 wt.%). In contrast, NO^-3 (34 wt.%) was the most abundant species in the haze periods (hourly PM2.5 〉 75 μg/m^3), followed by SO^2-4 (29.2 wt.%) and NH^+4 (16.3 wt.%), while SC94 (35 wt.%) was the most abundant species in the clean periods (hourly PM2.5 〈 75 μg/m^3), followed by NO^-3 (23.1 wt.%) and NH^+4 (11 wt.%). Being different from the acidic nature in the non-LNY periods, aerosol in the LNY period presented an alkaline nature with a pH value of 7.8 ± 1.3. LWC during the LNY period showed a robust linear correlation with K2SO4 and KC1, suggesting that aerosol hygroscopicity was dominated by inorganic salts derived from fireworks burning. Analysis of correlations between the ratios of NO^-3/SO^2-4 and NH^+4/SO^2-4 indicated that heterogeneous reaction of HNO3 with NH3 was an important formation pathway of particulate nitrate and ammonium during the LNY period.展开更多
Size-resolved biogenic secondary organic aerosols (BSOA) derived from isoprene and monoterpene photooxidation in Qinghai Lake, Tibetan Plateau (a continental background site) and five cities of China were measured...Size-resolved biogenic secondary organic aerosols (BSOA) derived from isoprene and monoterpene photooxidation in Qinghai Lake, Tibetan Plateau (a continental background site) and five cities of China were measured using gas chromatography/mass spectrometry (GC/MS). Concentrations of the determined BSOA are higher in the cities than in the background and are also higher in summer than in winter. Moreover, strong positive correlations (R^2 = 0.44-0.90) between BSOA and sulfate were found at the six sites, suggesting that anthropogenic pollution (i.e., sulfate) could enhance SOA formation, because sulfate provides a surface favorable for acid-catalyzed formation of BSOA. Size distribution measurements showed that most of the determined SOA tracers are enriched in the fine mode (〈3.3 μm) except for cis-pinic and cis-pinonic acids, both presented a comparable mass in the fine and coarse (〉3.3 μm) modes, respectively. Mass ratio of oxidation products derived from isoprene to those from monoterpene in the five urban regions during summer are much less than those in Qinghai Lake region. In addition, in the five urban regions relative abundances of monoterpene oxidation products to SOA are much higher than those of isoprene. Such phenomena suggest that BSOA derived from monoterpenes are more abundant than those from isoprene in Chinese urban areas.展开更多
Short-term building energy predictions serve as one of the fundamental tasks in building operation management.While large numbers of studies have explored the value of various supervised machine learning techniques in...Short-term building energy predictions serve as one of the fundamental tasks in building operation management.While large numbers of studies have explored the value of various supervised machine learning techniques in energy predictions,few studies have addressed the potential data shortage problem in developing data-driven models.One promising solution is data augmentation,which aims to enrich existing building data resources for reliable predictive modeling.This study proposes a deep generative modeling-based data augmentation strategy for improving short-term building energy predictions.Two types of conditional variational autoencoders have been designed for synthetic energy data generation using fully connected and one-dimensional convolutional layers respectively.Data experiments have been designed to evaluate the value of data augmentation using actual measurements from 52 buildings.The results indicate that conditional variational autoencoders are capable of generating high-quality synthetic data samples,which in turns helps to enhance the accuracy in short-term building energy predictions.The average performance enhancement ratios in terms of CV-RMSE range between 12%and 18%.Practical guidelines have been obtained to ensure the validity and quality of synthetic building energy data.The research outcomes are valuable for enhancing the robustness and reliability of data-driven models for smart building operation management.展开更多
Mechanical cues from the extracellular matrix(ECM)microenvironment are known to be significant in modulating the fate of stem cells to guide developmental processes and maintain bodily homeostasis.Tissue engineering h...Mechanical cues from the extracellular matrix(ECM)microenvironment are known to be significant in modulating the fate of stem cells to guide developmental processes and maintain bodily homeostasis.Tissue engineering has provided a promising approach to the repair or regeneration of damaged tissues.Scaffolds are fundamental in cell-based regenerative therapies.Developing artificial ECM that mimics the mechanical properties of native ECM would greatly help to guide cell functions and thus promote tissue regeneration.In this review,we introduce various mechanical cues provided by the ECM including elasticity,viscoelasticity,topography,and external stimuli,and their effects on cell behaviours.Meanwhile,we discuss the underlying principles and strategies to develop natural or synthetic biomaterials with different mechanical properties for cellular modulation,and explore the mechanism by which the mechanical cues from biomaterials regulate cell function toward tissue regeneration.We also discuss the challenges in multimodal mechanical modulation of cell behaviours and the interplay between mechanical cues and other microenvironmental factors.展开更多
基金Supported by College Students'Innovation and Enterpreneurship Training Program of Yanbian University(ydbksky2017495)
文摘[Objectives]This study was conducted to investigate the control effects of silicon fertilizer on growth of kohlrabi(Brassica oleracea L.var.caulorapa DC.)and Plutella xylostella.[Methods]Yougui and Guishen were selected and sprayed onto kohlrabi for 1,2 and 3 times,forming difference treatments.[Results]Spraying the two kinds of silicon fertilizers for different times promoted the growth of leaf length,leaf width and leaf thickness of kohlrabi,improved chlorophyll contents in kohlrabi leaves and corm yield,and adversely affected P.xylostella.Furthermore,higher treatment times led to a more remarkably effect and higher harm to P.xylostella.[Conclusions]In production,spraying silicon fertilizer onto maize for 2-3 times could realize the purposes of improving kohlrabi yield and alleviating damage by P.xylostella.
基金The authors acknowledge the funding support from the EPSRC(Funding Reference Number EP/L015995/1&EP/W004860/1)the Royal Society(IEC\NSFC\201166)+1 种基金the National Natural Science Foundation of China(No.82111530157)the Priority Academic Program Development(PAPD)of Jiangsu Higher Education Institutions。
文摘There is a high demand for bespoke grafts to replace damaged or malformed bone and cartilage tissue.Three-dimensional(3D)printing offers a method of fabricating complex anatomical features of clinically relevant sizes.However,the construction of a scaffold to replicate the complex hierarchical structure of natural tissues remains challenging.This paper reports a novel biofabrication method that is capable of creating intricately designed structures of anatomically relevant dimensions.The beneficial properties of the electrospun fibre meshes can finally be realised in 3D rather than the current promising breakthroughs in two-dimensional(2D).The 3D model was created from commercially available computer-aided design software packages in order to slice the model down into many layers of slices,which were arrayed.These 2D slices with each layer of a defined pattern were laser cut,and then successfully assembled with varying thicknesses of 100μm or 200μm.It is demonstrated in this study that this new biofabrication technique can be used to reproduce very complex computer-aided design models into hierarchical constructs with micro and nano resolutions,where the clinically relevant sizes ranging from a simple cube of 20 mm dimension,to a more complex,50 mm-tall human ears were created.In-vitro cell-contact studies were also carried out to investigate the biocompatibility of this hierarchal structure.The cell viability on a micromachined electrospun polylactic-co-glycolic acid fibre mesh slice,where a range of hole diameters from 200μm to 500μm were laser cut in an array where cell confluence values of at least 85%were found at three weeks.Cells were also seeded onto a simpler stacked construct,albeit made with micromachined poly fibre mesh,where cells can be found to migrate through the stack better with collagen as bioadhesives.This new method for biofabricating hierarchical constructs can be further developed for tissue repair applications such as maxillofacial bone injury or nose/ear cartilage replacement in the future.
基金supported by the National Key R&D Program of China (No. 2017YFC0210000)the National Natural Science Funds of China for Distinguished Young Scholars (No. 41325014)the National Nature Science Foundation of China (No. 41773117)
文摘Fireworks burning releases massive fine particles and gaseous pollutants, significantly deteriorating air quality during Chinese Lunar New Year (LNY) period. To investigate the impact of the fireworks burning on the atmospheric aerosol chemistry, 1-hr time resolution of PM2.5 samples in Xi'an during the winter of 2016 including the LNY were collected and detected for inorganic ions, acidity and liquid water content (LWC) of the fine aerosols. PM2.5 during the LNY was 167 ± 87 μg/m^3, two times higher than the China National Ambient Air Quality Standard (75 μg/m^3). K^+ (28 wt.% of the total ion mass) was the most abundant ion in the LNY period, followed by SO^2-4 (25 wt.%) and C1^- (18 wt.%). In contrast, NO^-3 (34 wt.%) was the most abundant species in the haze periods (hourly PM2.5 〉 75 μg/m^3), followed by SO^2-4 (29.2 wt.%) and NH^+4 (16.3 wt.%), while SC94 (35 wt.%) was the most abundant species in the clean periods (hourly PM2.5 〈 75 μg/m^3), followed by NO^-3 (23.1 wt.%) and NH^+4 (11 wt.%). Being different from the acidic nature in the non-LNY periods, aerosol in the LNY period presented an alkaline nature with a pH value of 7.8 ± 1.3. LWC during the LNY period showed a robust linear correlation with K2SO4 and KC1, suggesting that aerosol hygroscopicity was dominated by inorganic salts derived from fireworks burning. Analysis of correlations between the ratios of NO^-3/SO^2-4 and NH^+4/SO^2-4 indicated that heterogeneous reaction of HNO3 with NH3 was an important formation pathway of particulate nitrate and ammonium during the LNY period.
基金supported by the China National Natural Science Fund for Distinguished Young Scholars (No. 41325014)the National Key R&D Plan (Quantitative Relationship and Regulation Principle between Regional Oxidation Capacity of Atmospheric and Air Quality) (No. 2017YFC0210000)+1 种基金the program from National Nature Science Foundation of China (No. 41773117) (No. 41405122, 91543116)the West Light Foundation of Chinese Academy of Sciences
文摘Size-resolved biogenic secondary organic aerosols (BSOA) derived from isoprene and monoterpene photooxidation in Qinghai Lake, Tibetan Plateau (a continental background site) and five cities of China were measured using gas chromatography/mass spectrometry (GC/MS). Concentrations of the determined BSOA are higher in the cities than in the background and are also higher in summer than in winter. Moreover, strong positive correlations (R^2 = 0.44-0.90) between BSOA and sulfate were found at the six sites, suggesting that anthropogenic pollution (i.e., sulfate) could enhance SOA formation, because sulfate provides a surface favorable for acid-catalyzed formation of BSOA. Size distribution measurements showed that most of the determined SOA tracers are enriched in the fine mode (〈3.3 μm) except for cis-pinic and cis-pinonic acids, both presented a comparable mass in the fine and coarse (〉3.3 μm) modes, respectively. Mass ratio of oxidation products derived from isoprene to those from monoterpene in the five urban regions during summer are much less than those in Qinghai Lake region. In addition, in the five urban regions relative abundances of monoterpene oxidation products to SOA are much higher than those of isoprene. Such phenomena suggest that BSOA derived from monoterpenes are more abundant than those from isoprene in Chinese urban areas.
基金support of this research by the National Natural Science Foundation of China(No.51908365,No.71772125)the Philosophical and Social Science Program of Guangdong Province,China(GD18YGL07).
文摘Short-term building energy predictions serve as one of the fundamental tasks in building operation management.While large numbers of studies have explored the value of various supervised machine learning techniques in energy predictions,few studies have addressed the potential data shortage problem in developing data-driven models.One promising solution is data augmentation,which aims to enrich existing building data resources for reliable predictive modeling.This study proposes a deep generative modeling-based data augmentation strategy for improving short-term building energy predictions.Two types of conditional variational autoencoders have been designed for synthetic energy data generation using fully connected and one-dimensional convolutional layers respectively.Data experiments have been designed to evaluate the value of data augmentation using actual measurements from 52 buildings.The results indicate that conditional variational autoencoders are capable of generating high-quality synthetic data samples,which in turns helps to enhance the accuracy in short-term building energy predictions.The average performance enhancement ratios in terms of CV-RMSE range between 12%and 18%.Practical guidelines have been obtained to ensure the validity and quality of synthetic building energy data.The research outcomes are valuable for enhancing the robustness and reliability of data-driven models for smart building operation management.
基金supported by the National Natural Science Foundation of China(Nos.81925027,81871805,31530024,81672213)National Key R&D Program of China(No.2016YFC1100203)+3 种基金Jiangsu Provincial Clinical Orthopaedic Centre,Key Laboratory of Stem CellsBiomedical Materials of Jiangsu ProvinceChinese Ministry of Science and Technology of Chinathe Priority Academic Program Development(PAPD)of Jiangsu Higher Education Institutions of China.
文摘Mechanical cues from the extracellular matrix(ECM)microenvironment are known to be significant in modulating the fate of stem cells to guide developmental processes and maintain bodily homeostasis.Tissue engineering has provided a promising approach to the repair or regeneration of damaged tissues.Scaffolds are fundamental in cell-based regenerative therapies.Developing artificial ECM that mimics the mechanical properties of native ECM would greatly help to guide cell functions and thus promote tissue regeneration.In this review,we introduce various mechanical cues provided by the ECM including elasticity,viscoelasticity,topography,and external stimuli,and their effects on cell behaviours.Meanwhile,we discuss the underlying principles and strategies to develop natural or synthetic biomaterials with different mechanical properties for cellular modulation,and explore the mechanism by which the mechanical cues from biomaterials regulate cell function toward tissue regeneration.We also discuss the challenges in multimodal mechanical modulation of cell behaviours and the interplay between mechanical cues and other microenvironmental factors.