Nuclear factor Y （NF-Y） is a highly conserved transcription factor presented in all eukaryotic organisms, and is a heterotrimer consisting of three subunits： NF-YA, NF-YB, and NF-YC. In Arabidopsis, these three sub...Nuclear factor Y （NF-Y） is a highly conserved transcription factor presented in all eukaryotic organisms, and is a heterotrimer consisting of three subunits： NF-YA, NF-YB, and NF-YC. In Arabidopsis, these three subunits are encoded by multigene families. The best-studied member of the NF-Y transcription factors is LEAFY COTYLEDON1 （LEC1）, a NF-YB family member, which plays a critical role in embryogenesis and seed maturation. However, the function of most NF-Y genes remains elusive. Here, we report the characterization of four genes in the NF-YA family. We found that a gain- of-function mutant of NF-YA1 showed defects in male gametogenesis and embryogenesis. Consistently, overexpression of NF-YA1, 5, 6, and 9 affects male gametogenesis, embryogenesis, seed morphology, and seed germination, with a stronger phenotype when overexpressing NF-YA1 and NF-YA9. Moreover, overexpression of these NF-YA genes also causes hypersensitivity to abscisic acid （ABA） during seed germination, retarded seedling growth, and late flowering at different degrees. Intriguingly, overexpression of NF-YA1, 5, 6, and 9 is sufficient to induce the formation of somatic embryos from the vegetative tissues. However, single or double mutants of these NF-YA genes do not have detectable phenotype. Collectively, these results provide evidence that NF-YA1, 5, 6, and 9 play redundant roles in male gameto- phyte development, embryogenesis, seed development, and post-germinative growth.展开更多
Is Chinese urbanization going to take a long time, or can its development goal be achieved by the government in a short time? What is the highest stable urbanization level that China can reach? When can China complete...Is Chinese urbanization going to take a long time, or can its development goal be achieved by the government in a short time? What is the highest stable urbanization level that China can reach? When can China complete its urbanization? To answer these questions, this paper presents a system dynamic(SD) model of Chinese urbanization, and its validity and simulation are justified by a stock-flow test and a sensitivity analysis using real data from 1998 to 2013. Setting the initial conditions of the simulation by referring to the real data of 2013, the multi-scenario analysis from 2013 to 2050 reveals that Chinese urbanization will reach a level higher than 70% in 2035 and then proceed to a slow urbanization stage regardless of the population policy and GDP growth rate settings; in 2050, Chinese urbanization levels will reach approximately 75%, which is a stable and equilibrium level for China. Thus, it can be argued that Chinese urbanization is a long social development process that will require approximately20 years to complete and that the ultimate urbanization level will be 75–80%, which means that in the distant future, 20–25% of China's population will still settle in rural regions of China.展开更多
The Yellow River valley is one of the three largest cotton production areas in China.An experiment was performed in cotton fields of Anyang,China from 2013 to 2014 to investigate the effects of nitrogen(N) application...The Yellow River valley is one of the three largest cotton production areas in China.An experiment was performed in cotton fields of Anyang,China from 2013 to 2014 to investigate the effects of nitrogen(N) application rate and the ratio between basal and topdressing N fertilizer on N balance in a soil-plant system,N use efficiency,and cotton yield.Five N application rates as treatments were applied with the same split application ratio.Half of the N(50% basal fertilizer) was applied at pre-planting and the other half(50% topdressing fertilizer) at the initial flowering stage.These treatments were:zero N(N0,control),90 kg N ha^(-1)(N90(5/5)),180 kg N ha^(-1)(N180(5/5)),270 kg N ha^(-1)(N270(5/5),a reduced N rate),and 360 kg N ha^(-1)(N360(5/5),a conventional N rate).Additional 2 split application ratios as treatments were applied with the same N rate of 270 kg N ha^(-1).The split application ratios between basal N and topdressing N were 30%:70%(N270(3/7)) and 70%:30%(N270(7/3)).Results demonstrated that soil NH_4-N content in the 0–60 cm layer and NO3-N content in the 0–20 cm layer increased with increased N rate at the squaring and boll-opening stages and then decreased to lower levels at the initial flowering and harvest stages.Soil NO_3-N content in the 20–60 cm layer after the initial flowering stage increased with the increase of topdressing N rate.Soil apparent N surplus varied at different growth stages,while the soil apparent N surplus over the entire growth period exhibited a positive relationship at N rates over 180 kg ha^(-1).Seed cotton yield of N270(3/7) was the highest of all treatments.Plant N uptake,N agronomic efficiency,and apparent N recovery efficiency of N270(3/7) were significantly higher than those of N270(5/5) and N270(7/3) in both growing seasons.These suggest both economic and ecological benefits in cotton production in the Yellow River valley could be created,by appropriately reducing total N application rate and increasing the ratio of topdressing to basal N fertilizer at the init展开更多
Conjugated, conductive polymers are a kind of important organic macromolecules, which has found appli- cations in a variety of areas. The application of conjugated polymers in developing fluorescent biosensors represe...Conjugated, conductive polymers are a kind of important organic macromolecules, which has found appli- cations in a variety of areas. The application of conjugated polymers in developing fluorescent biosensors represents the merge of polymer sciences and biological sciences. Conju- gated polymers are very good light harvesters as well as fluorescent polymers, and they are also “molecular wires”. Through elaborate designs, these important features, i.e. efficient light harvesting and electron/energy transfer, can be used as signal amplification in fluorescent biosensors. This might significantly improve the sensitivity of conjugated polymer-based biosensors. In this article, we reviewed the application of conjugated polymers, via either electron transfer or energy transfer, to detections of gene targets, an- tibodies or enzymes. We also reviewed recent efforts in con- jugated polymer-based solid-state sensor designs as well as chip-based multiple target detection. Possible directions in this conjugated polymer-based biosensor area are also dis- cussed.展开更多
Government credibility is an important asset of contemporary national governance, an important criterion for evaluating government legitimacy, and a key factor in measuring the effectiveness of government governance. ...Government credibility is an important asset of contemporary national governance, an important criterion for evaluating government legitimacy, and a key factor in measuring the effectiveness of government governance. In recent years, researchers’ research on government credibility has mostly focused on exploring theories and mechanisms, with little empirical research on this topic. This article intends to apply variable selection models in the field of social statistics to the issue of government credibility, in order to achieve empirical research on government credibility and explore its core influencing factors from a statistical perspective. Specifically, this article intends to use four regression-analysis-based methods and three random-forest-based methods to study the influencing factors of government credibility in various provinces in China, and compare the performance of these seven variable selection methods in different dimensions. The research results show that there are certain differences in simplicity, accuracy, and variable importance ranking among different variable selection methods, which present different importance in the study of government credibility issues. This study provides a methodological reference for variable selection models in the field of social science research, and also offers a multidimensional comparative perspective for analyzing the influencing factors of government credibility.展开更多
The Hoechst and DOX tunnel images of the DOX-C_(22) ANPs group at 4 h in Fig.4(a)were mistakenly used with the neighboring images of DOX-C_(26) ANPs group.The images were corrected as follows to be correspondence with...The Hoechst and DOX tunnel images of the DOX-C_(22) ANPs group at 4 h in Fig.4(a)were mistakenly used with the neighboring images of DOX-C_(26) ANPs group.The images were corrected as follows to be correspondence with the accurate merged image.展开更多
The ubiquitous implementation of integrated microelectronics requires the on-chip power sources featured with the lightweight configuration design,high areal-capacity-loadings as well as facile reaction kinetics that ...The ubiquitous implementation of integrated microelectronics requires the on-chip power sources featured with the lightweight configuration design,high areal-capacity-loadings as well as facile reaction kinetics that beyond the current available microbattery prototypes.Herein,this study constructs a mechanically flexible,nanocellulose fiber(NCF)reinforced microbattery configuration,which consists of metal-organic frameworks(ZIF-8)modified NCF as the separator(MOF@NCF),the carbonized MOF@NCF as the metallic deposition substrate(c-MOF@NCF)as well as gradient-structured LiFePO4 particles infiltrated in the NCF matrix(LFP@NCF)as the cathode.The film-stacked,integrated NCF-based microbattery prototype not only achieves the facile reaction kinetics with homogenized,dendrite-free Li metal deposition at high-capacity-loadings(2 mAh·cm^(-2)),but also eliminates the necessary use of metallic current collector to maximize the electroactive mass ratio,which therefore enables the high energy density of 6.8 mWh·cm^(-2)at the power output of 1.36 mW·cm^(-2)as well as the robust cyclability upon various geometric flexing states.This study presents a quantum leap towards the facile reaction kinetics and multi-scale interfacial stability for the flexible microbattery construction that based on the sustainable utilization of bio-scaffolds.展开更多
The postgenomic era has seen an emergence of new applications of DNA manipulation technologies, including DNA-based molecular computing. Surface DNA computing has already been reported in a number of studies that,howe...The postgenomic era has seen an emergence of new applications of DNA manipulation technologies, including DNA-based molecular computing. Surface DNA computing has already been reported in a number of studies that,however, all employ different mechanisms other than automaton functions. Here we describe a programmable DNA surface-computing device as a Turing machine-like finite automaton. The laboratory automaton is primarily composed of DNA (inputs, output-detectors, transition molecules as software), DNA manipulating enzymes and buffer system that solve artificial computational problems autonomously. When fluoresceins were labeled in the 5' end of (-) strand of the input molecule, direct observation of all reaction intermediates along the time scale was made so that the dynamic process of DNA computing could be conveniently visualized. The features of this study are: (i) achievement of finite automaton functions by linearly programmed DNA computer operated on magnetic particle surface and (ii)direct detection of all DNA computing intermediates by capiilary electrophoresis. Since DNA computing has the massive parallelism and feasibility for automation, this achievement sets a basis for large-scale implications of DNA computing for functional genomics in the near future.展开更多
Albumin nanoparticles(ANPs)offer unique advantages for antitumor drug delivery system,including non-immunogenicity and inherent tumor-targeting capacity.At present,only a few products,such as ABRAXANE®and FYARRO™...Albumin nanoparticles(ANPs)offer unique advantages for antitumor drug delivery system,including non-immunogenicity and inherent tumor-targeting capacity.At present,only a few products,such as ABRAXANE®and FYARRO™,have been approved for clinical applications.The poor affinity of doxorubicin(DOX)for albumin,coupled with its numerous severe adverse reactions,poses challenges in the fabrication of desirable albumin nanoparticles loaded with DOX.In this study,we developed prodrugs by conjugating fatty acids of varying lengths with DOX.Our aim was to investigate the balance between efficacy and safety through the selection of appropriate modules.We synthesized five pH-sensitive doxorubicin-fatty acid prodrugs.Compared to free DOX,all DOX prodrug ANPs exhibited a uniform size distribution with desirable sizes of 150 nm.Additionally,DOX prodrugs with hydrazone bonds remained intact in blood circulation while releasing DOX within tumor cells.Significantly,the characteristics of prodrug ANPs were considerably influenced by the length of fatty acids,impacting their in vivo pharmacokinetics,antitumor effectiveness and tumor accumulation.This research offers a detailed understanding of the length of fatty acid influence on DOX-fatty acid prodrug-based ANPs,and it builds a good platform for creating ANPs which prioritize high drug loading,high efficiency,and minimal side effects.展开更多
AIM:To evaluate and compare the peripapillary and retinal vasculature changes in primary open angle glaucoma(POAG),pseudoexfoliation glaucoma(PXG),ocular hypertension(OHT)and normal eyes using optical coherence tomogr...AIM:To evaluate and compare the peripapillary and retinal vasculature changes in primary open angle glaucoma(POAG),pseudoexfoliation glaucoma(PXG),ocular hypertension(OHT)and normal eyes using optical coherence tomography angiography(OCTA).METHODS:A total of 114 POAG,PXG and OHT eyes of 60 patients and 46 eyes of 23 healthy control participants with good quality OCTA images were included.The PXG,POAG,OHT,and control groups(aged 68.17±6.30 y,61.11±10.26 y,58.1±8.9 y,and 56.9±4.6 y,respectively)contained of 46,36,32,and 46 eyes,respectively.Measurements of vessel density(VD)in the peripapillary region and macula,average retinal inner thickness,and retinal nerve fiber layer thickness(RNFLT)were compared among groups.In order to test the accuracy of differentiation between eyes with and without glaucoma,the area was calculated under the receiver operating characteristic(ROC)curves.RESULTS:The VD in glaucomatous eyes was significantly lower than the control group in all peripapillary sectors(44.35%±6.78%vs 50.47%±1.83%,P<0.001),the superficial(44.08%±5.46%vs 51.28%±2.85%,P<0.001)and the deep(45.13%±8.55%vs 54.20%±5.44%,P<0.001)vascular plexus.There was a significant difference in peripapillary VD between glaucomatous and OHT eyes(44.35%±6.78%vs 49.86%±2.45%,P<0.001).The OHT group featured a lower superficial(48.06%±4.32%vs 51.28%±2.85%,P=0.027)and deep plexus(48.70%±5.99%vs 54.20%±5.44%,P=0.013)whole image vessel density(wiVD)than did the control group.The average macular superficial plexus wiVD was significantly lower in eyes with PXG than in eyes with POAG(42.22%±5.36%vs 46.54%±5.56%,P=0.046).CONCLUSION:OCTA can measure reduced peripapillary and macular VD in eyes with glaucoma and OHT,and these results are correlated to functional and structural glaucomatous alterations.Peripapillary and macular superficial plexus VD is lower in eyes with PXG than in eyes with POAG.Furthermore,the OHT eyes demonstrate impaired macular vasculature in both superficial and deep plexus.展开更多
Pancharatnam–Berry(PB)phase metasurface,as a special class of gradient metasurfaces,has been paid much attention owing to the robust performance for phase control of circularly polarized waves.Herein,we present an el...Pancharatnam–Berry(PB)phase metasurface,as a special class of gradient metasurfaces,has been paid much attention owing to the robust performance for phase control of circularly polarized waves.Herein,we present an element-based polarizer for the first step,which enables the incident electromagnetic waves into the cross-polarized waves with the relative bandwidth of 71%,and the polarization conversion ratio exceeds 90%at 6.9–14.5 GHz.Then an eight-elements coding polarizer based on the PB phase is presented for the applications on beam control and radar cross section reduction.The simulated values indicate that the reduction of radar cross section is more than 10 dB at 6–16 GHz.Our work reveals the availability of manipulating the waves,beamforming in communication systems and electromagnetic stealth,and so on.展开更多
According to the regulations of the People＇s Republic of China national standard as the basis, on the part of chemical industry product quality inspection and analysis of the implementation of computer management has...According to the regulations of the People＇s Republic of China national standard as the basis, on the part of chemical industry product quality inspection and analysis of the implementation of computer management has developed a set of software applications, the software in chemical products quality inspection and analysis of the means of management is an innovation. The software functions, can automatically process data, judge the product grade, quality analysis, objective and fair, convenient, fast, accurate, stable, practical, and easy to popularize.展开更多
Erratum to Nano Research 2022,15(10):9092-9104 https://doi.org/10.1007/s12274-022-4544-7 Figure 9 was unfortunately mistakenly typeset.This error did not affect any of the conclusions from the published paper.
The practical deployment of metallic anodes in the energy-dense batteries is impeded by the thermodynamically unstable interphase in contact with the aprotic electrolyte,structural collapse of the substrates as well a...The practical deployment of metallic anodes in the energy-dense batteries is impeded by the thermodynamically unstable interphase in contact with the aprotic electrolyte,structural collapse of the substrates as well as their insufficient affinity toward the metallic deposits.Herein,the mechanical flexible,lightweight(1.2 mg cm^(−2))carbon nanofiber scaffold with the monodispersed,ultrafine Sn_(4)P_(3) nanoparticles encapsulation(Sn_(4)P_(3)NPs@CNF)is proposed as the deposition substrate toward the high-areal-capacity sodium loadings up to 4 mAh cm^(−2).First-principles calculations manifest that the alloy intermediates,namely the Na_(15)Sn_(4) and Na_(3)P matrix,exhibit the intimate Na affinity as the“sodiophilic”sites.Meanwhile,the porous CNF regulates the heterogeneous alloying process and confines the deposit propagation along the nanofiber orientation.With the precise control of pairing mode with the NaVPO4F cathode(8.7 mg cm^(−2)),the practical feasibility of the Sn_(4)P_(3) NPs@CNF anode(1^(*)Na excess)is demonstrated in 2 mAh single-layer pouch cell prototype,which achieves the 95.7%capacity retention for 150 cycles at various mechanical flexing states as well as balanced energy/power densities.展开更多
Selenium(Se)is an essential micronutrient for lives.Indigenous microbial communities play an important role on Se geochemistry in soils.In this study,the microbial community composition and functions of 53 soil sample...Selenium(Se)is an essential micronutrient for lives.Indigenous microbial communities play an important role on Se geochemistry in soils.In this study,the microbial community composition and functions of 53 soil samples were investigated using high-throughput sequencing.Samples were divided into 3 groups with different farming types based on the measured geochemical parameters and microbial functional structures.Results indicated that putative Se related bacteria Bacillus,Dyella,Paenibacillus,Burkholderia and Brevibacillus were dominant in dryland plantation soils which were characterized with higher available Se and low contents of H_(2)O,total organic carbon(TOC),NH_(4)^(+) and NO_(2)^(-).In contrast,the putative denitrifier Pseudomonas dominated in flooded paddy soils with higher TOC,NO_(3)^(-) and organic Se,whereas genera Rhizobium,Nitrosospira,and Geobacter preferred woodland soils with higher oxidation-reduction potential(ORP),pH,NH_(4)^(+) and Fe.Farming patterns resulted in distinct geochemical parameters including moisture,pH,ORP,TOC,and contents of soluble Fe,NO_(2)^(-) and NH_(4)^(+),shaping the microbial communities,which in turn affected Se forms in soils.This study provides a valuable insight into understanding of Se biogeochemistry in soils and prospective strategy for Se-rich agriculture production.展开更多
Background Potassium(K)is an essential nutrient for plant growth and development.However,plant fertilization ignoring the soil K level is very likely to cause excessive fertilizer use,and further arouse a series of si...Background Potassium(K)is an essential nutrient for plant growth and development.However,plant fertilization ignoring the soil K level is very likely to cause excessive fertilizer use,and further arouse a series of side effects.This study investigated the response of cotton growth to different soil K levels and the uptake of major nutrients,aiming to evaluate the appropriate K supply level for cotton growth.Using a random block design with 6 soil K levels,we conducted 18 micro-zones field experiments over two continuous years.The soil available K concentration of each treatment was K1(99.77-100.90 mg·kg^(-1)),K2(110.90-111.26 mg·kg^(-1)),K3(123.48-128.88 mg·kg^(-1)),K4(140.13-145.10 mg·kg^(-1)),K5(154.43-155.38 mg·kg^(-1)),and K6(165.77-168.75 mg·kg^(-1)).Cotton nutrient contents,soil nutrient contents,accumulation and distribution of dry matter in cotton were determined,and the relationships between K content in soil and plants and dry matter accumulation were analyzed.Results The soil K content had a significantly positive relationship with dry matter and K accumulation in cotton plants.There were significant differences in dry matter accumulation,single-plant seed cotton yield,mineral nutrient uptake and the proportion of K accumulation in reproductive organs among different soil K levels.The results showed that there was significant difference between K4 and lower K level treatments(K1 and K2),but no significant difference between K4 and higher K level treatments(K5 and K6)in dry matter,single-plant seed cotton yield,or accumulation,distribution and seed cotton production efficiency of N,P and K.Conclusion The soil K level of K4 was able to provide sufficient K for cotton growth in our experiment.Therefore,when the soil K level reached 140.13 mg·kg^(-1),further increasing the soil K concentration no longer had a significant positive effect on cotton growth.展开更多
Osteosarcoma(OS)is the most common primary bone tumor in children and adolescents.It is an aggressive tumor with a tendency to spread to the lung,which is the most common site of metastasis.Patients with advanced OS w...Osteosarcoma(OS)is the most common primary bone tumor in children and adolescents.It is an aggressive tumor with a tendency to spread to the lung,which is the most common site of metastasis.Patients with advanced OS with metastases have poor prognoses despite the application of chemotherapy,thus highlighting the need for novel therapeutic targets.The tumor microenvironment(TME)of OS is confirmed to be essential for and supportive of tumor growth and dissemination.The immune component of the OS microenvironment is mainly composed of tumor-associated macrophages(TAMs).In OS,TAMs promote tumor growth and angiogenesis and upregulate the cancer stem cell-like phenotype.However,TAMs inhibit the metastasis of OS.Therefore,much attention has been paid to investigating the mechanism of TAMs in OS development and the progression of immunotherapy for OS.In this article,we aim to summarize the roles of TAMs in OS and the major findings on the application of TAMs in OS treatment.展开更多
Thylakoid(Tk)membranes are of unique superiority in photodynamic therapy(PDT)because they not only carry abundant chlorophylls containing photosensitizer porphyrin but also can produce O_(2).However,the current therap...Thylakoid(Tk)membranes are of unique superiority in photodynamic therapy(PDT)because they not only carry abundant chlorophylls containing photosensitizer porphyrin but also can produce O_(2).However,the current therapeutic performance of Tk is dramatically limited because of their poor tumor targeting and inefficient O_(2) production.Here,we report an immunomodulatory bio-nanovesicle of Tk membranes fused with M1 macrophage-derived extracellular vesicles(M1 EV)for efficient PDT of tumors.The hybrid nanovesicle Tk@M1 was prepared by squeezing the Tk membranes of spinach with M1 EV.The systemic study confirmed that Tk@M1 can not only actively accumulate in tumors but also effectively regulate the inactive immune microenvironment of tumors.Such activated"hot"tumors significantly enhance the PDT efficacy of Tk@M1 attributed to the increased O_(2) from catalase catalyzed decomposition of augmented H_(2)O_(2),providing a novel idea about constructing natural systems for effective tumor treatment.展开更多
基金This work was supported by grants from the National Natural Science Foundation of China （31071449）, the Ministry of Science and Technology of China （2009CB941502）, and the National Transgenic Research Project （2009ZX08009-115B）.
文摘Nuclear factor Y （NF-Y） is a highly conserved transcription factor presented in all eukaryotic organisms, and is a heterotrimer consisting of three subunits： NF-YA, NF-YB, and NF-YC. In Arabidopsis, these three subunits are encoded by multigene families. The best-studied member of the NF-Y transcription factors is LEAFY COTYLEDON1 （LEC1）, a NF-YB family member, which plays a critical role in embryogenesis and seed maturation. However, the function of most NF-Y genes remains elusive. Here, we report the characterization of four genes in the NF-YA family. We found that a gain- of-function mutant of NF-YA1 showed defects in male gametogenesis and embryogenesis. Consistently, overexpression of NF-YA1, 5, 6, and 9 affects male gametogenesis, embryogenesis, seed morphology, and seed germination, with a stronger phenotype when overexpressing NF-YA1 and NF-YA9. Moreover, overexpression of these NF-YA genes also causes hypersensitivity to abscisic acid （ABA） during seed germination, retarded seedling growth, and late flowering at different degrees. Intriguingly, overexpression of NF-YA1, 5, 6, and 9 is sufficient to induce the formation of somatic embryos from the vegetative tissues. However, single or double mutants of these NF-YA genes do not have detectable phenotype. Collectively, these results provide evidence that NF-YA1, 5, 6, and 9 play redundant roles in male gameto- phyte development, embryogenesis, seed development, and post-germinative growth.
基金supported by the Key Project of the National Natural Science Foundation of China “the SD model and threshold value prediction of the interactive coupled effects between urbanization and eco-environment in mega-urban agglomerations” (Grant No. 41590844)the Independent Research Program of Tsinghua University (Grant No. 2015THZ01)
文摘Is Chinese urbanization going to take a long time, or can its development goal be achieved by the government in a short time? What is the highest stable urbanization level that China can reach? When can China complete its urbanization? To answer these questions, this paper presents a system dynamic(SD) model of Chinese urbanization, and its validity and simulation are justified by a stock-flow test and a sensitivity analysis using real data from 1998 to 2013. Setting the initial conditions of the simulation by referring to the real data of 2013, the multi-scenario analysis from 2013 to 2050 reveals that Chinese urbanization will reach a level higher than 70% in 2035 and then proceed to a slow urbanization stage regardless of the population policy and GDP growth rate settings; in 2050, Chinese urbanization levels will reach approximately 75%, which is a stable and equilibrium level for China. Thus, it can be argued that Chinese urbanization is a long social development process that will require approximately20 years to complete and that the ultimate urbanization level will be 75–80%, which means that in the distant future, 20–25% of China's population will still settle in rural regions of China.
基金supported by the National Key Technology Support Program of China(No.2014BAD03B02)the Professional(Agricultural) Researching Project for Public Interests,China(Nos.201203096 and 201503121)the Earmarked Fund for the Modern Agro-Industry Technology Research System,China(No.CARS-18-17)
文摘The Yellow River valley is one of the three largest cotton production areas in China.An experiment was performed in cotton fields of Anyang,China from 2013 to 2014 to investigate the effects of nitrogen(N) application rate and the ratio between basal and topdressing N fertilizer on N balance in a soil-plant system,N use efficiency,and cotton yield.Five N application rates as treatments were applied with the same split application ratio.Half of the N(50% basal fertilizer) was applied at pre-planting and the other half(50% topdressing fertilizer) at the initial flowering stage.These treatments were:zero N(N0,control),90 kg N ha^(-1)(N90(5/5)),180 kg N ha^(-1)(N180(5/5)),270 kg N ha^(-1)(N270(5/5),a reduced N rate),and 360 kg N ha^(-1)(N360(5/5),a conventional N rate).Additional 2 split application ratios as treatments were applied with the same N rate of 270 kg N ha^(-1).The split application ratios between basal N and topdressing N were 30%:70%(N270(3/7)) and 70%:30%(N270(7/3)).Results demonstrated that soil NH_4-N content in the 0–60 cm layer and NO3-N content in the 0–20 cm layer increased with increased N rate at the squaring and boll-opening stages and then decreased to lower levels at the initial flowering and harvest stages.Soil NO_3-N content in the 20–60 cm layer after the initial flowering stage increased with the increase of topdressing N rate.Soil apparent N surplus varied at different growth stages,while the soil apparent N surplus over the entire growth period exhibited a positive relationship at N rates over 180 kg ha^(-1).Seed cotton yield of N270(3/7) was the highest of all treatments.Plant N uptake,N agronomic efficiency,and apparent N recovery efficiency of N270(3/7) were significantly higher than those of N270(5/5) and N270(7/3) in both growing seasons.These suggest both economic and ecological benefits in cotton production in the Yellow River valley could be created,by appropriately reducing total N application rate and increasing the ratio of topdressing to basal N fertilizer at the init
文摘Conjugated, conductive polymers are a kind of important organic macromolecules, which has found appli- cations in a variety of areas. The application of conjugated polymers in developing fluorescent biosensors represents the merge of polymer sciences and biological sciences. Conju- gated polymers are very good light harvesters as well as fluorescent polymers, and they are also “molecular wires”. Through elaborate designs, these important features, i.e. efficient light harvesting and electron/energy transfer, can be used as signal amplification in fluorescent biosensors. This might significantly improve the sensitivity of conjugated polymer-based biosensors. In this article, we reviewed the application of conjugated polymers, via either electron transfer or energy transfer, to detections of gene targets, an- tibodies or enzymes. We also reviewed recent efforts in con- jugated polymer-based solid-state sensor designs as well as chip-based multiple target detection. Possible directions in this conjugated polymer-based biosensor area are also dis- cussed.
文摘Government credibility is an important asset of contemporary national governance, an important criterion for evaluating government legitimacy, and a key factor in measuring the effectiveness of government governance. In recent years, researchers’ research on government credibility has mostly focused on exploring theories and mechanisms, with little empirical research on this topic. This article intends to apply variable selection models in the field of social statistics to the issue of government credibility, in order to achieve empirical research on government credibility and explore its core influencing factors from a statistical perspective. Specifically, this article intends to use four regression-analysis-based methods and three random-forest-based methods to study the influencing factors of government credibility in various provinces in China, and compare the performance of these seven variable selection methods in different dimensions. The research results show that there are certain differences in simplicity, accuracy, and variable importance ranking among different variable selection methods, which present different importance in the study of government credibility issues. This study provides a methodological reference for variable selection models in the field of social science research, and also offers a multidimensional comparative perspective for analyzing the influencing factors of government credibility.
文摘The Hoechst and DOX tunnel images of the DOX-C_(22) ANPs group at 4 h in Fig.4(a)were mistakenly used with the neighboring images of DOX-C_(26) ANPs group.The images were corrected as follows to be correspondence with the accurate merged image.
基金the financial support of the National Natural Science Foundation of China(Nos.52173229 and 52373229)the Natural Science Foundation of Shaanxi(Nos.2019KJXX-099 and 2023-JC-JQ-15)+2 种基金the Fundamental Research Funds for the Central Universities(Nos.3102019JC005 and D5000230114)the Key R&D Program of Shaanxi Province(No.2019ZDLGY04-05)the Outstanding Youth Scientist Foundation of Hunan Province(No.2021JJ10017).
文摘The ubiquitous implementation of integrated microelectronics requires the on-chip power sources featured with the lightweight configuration design,high areal-capacity-loadings as well as facile reaction kinetics that beyond the current available microbattery prototypes.Herein,this study constructs a mechanically flexible,nanocellulose fiber(NCF)reinforced microbattery configuration,which consists of metal-organic frameworks(ZIF-8)modified NCF as the separator(MOF@NCF),the carbonized MOF@NCF as the metallic deposition substrate(c-MOF@NCF)as well as gradient-structured LiFePO4 particles infiltrated in the NCF matrix(LFP@NCF)as the cathode.The film-stacked,integrated NCF-based microbattery prototype not only achieves the facile reaction kinetics with homogenized,dendrite-free Li metal deposition at high-capacity-loadings(2 mAh·cm^(-2)),but also eliminates the necessary use of metallic current collector to maximize the electroactive mass ratio,which therefore enables the high energy density of 6.8 mWh·cm^(-2)at the power output of 1.36 mW·cm^(-2)as well as the robust cyclability upon various geometric flexing states.This study presents a quantum leap towards the facile reaction kinetics and multi-scale interfacial stability for the flexible microbattery construction that based on the sustainable utilization of bio-scaffolds.
文摘The postgenomic era has seen an emergence of new applications of DNA manipulation technologies, including DNA-based molecular computing. Surface DNA computing has already been reported in a number of studies that,however, all employ different mechanisms other than automaton functions. Here we describe a programmable DNA surface-computing device as a Turing machine-like finite automaton. The laboratory automaton is primarily composed of DNA (inputs, output-detectors, transition molecules as software), DNA manipulating enzymes and buffer system that solve artificial computational problems autonomously. When fluoresceins were labeled in the 5' end of (-) strand of the input molecule, direct observation of all reaction intermediates along the time scale was made so that the dynamic process of DNA computing could be conveniently visualized. The features of this study are: (i) achievement of finite automaton functions by linearly programmed DNA computer operated on magnetic particle surface and (ii)direct detection of all DNA computing intermediates by capiilary electrophoresis. Since DNA computing has the massive parallelism and feasibility for automation, this achievement sets a basis for large-scale implications of DNA computing for functional genomics in the near future.
基金the National Key R&D Program of China(No.2022YFE0111600)National Natural Science Foundation of China(Nos.82272151 and 82204318)。
文摘Albumin nanoparticles(ANPs)offer unique advantages for antitumor drug delivery system,including non-immunogenicity and inherent tumor-targeting capacity.At present,only a few products,such as ABRAXANE®and FYARRO™,have been approved for clinical applications.The poor affinity of doxorubicin(DOX)for albumin,coupled with its numerous severe adverse reactions,poses challenges in the fabrication of desirable albumin nanoparticles loaded with DOX.In this study,we developed prodrugs by conjugating fatty acids of varying lengths with DOX.Our aim was to investigate the balance between efficacy and safety through the selection of appropriate modules.We synthesized five pH-sensitive doxorubicin-fatty acid prodrugs.Compared to free DOX,all DOX prodrug ANPs exhibited a uniform size distribution with desirable sizes of 150 nm.Additionally,DOX prodrugs with hydrazone bonds remained intact in blood circulation while releasing DOX within tumor cells.Significantly,the characteristics of prodrug ANPs were considerably influenced by the length of fatty acids,impacting their in vivo pharmacokinetics,antitumor effectiveness and tumor accumulation.This research offers a detailed understanding of the length of fatty acid influence on DOX-fatty acid prodrug-based ANPs,and it builds a good platform for creating ANPs which prioritize high drug loading,high efficiency,and minimal side effects.
文摘AIM:To evaluate and compare the peripapillary and retinal vasculature changes in primary open angle glaucoma(POAG),pseudoexfoliation glaucoma(PXG),ocular hypertension(OHT)and normal eyes using optical coherence tomography angiography(OCTA).METHODS:A total of 114 POAG,PXG and OHT eyes of 60 patients and 46 eyes of 23 healthy control participants with good quality OCTA images were included.The PXG,POAG,OHT,and control groups(aged 68.17±6.30 y,61.11±10.26 y,58.1±8.9 y,and 56.9±4.6 y,respectively)contained of 46,36,32,and 46 eyes,respectively.Measurements of vessel density(VD)in the peripapillary region and macula,average retinal inner thickness,and retinal nerve fiber layer thickness(RNFLT)were compared among groups.In order to test the accuracy of differentiation between eyes with and without glaucoma,the area was calculated under the receiver operating characteristic(ROC)curves.RESULTS:The VD in glaucomatous eyes was significantly lower than the control group in all peripapillary sectors(44.35%±6.78%vs 50.47%±1.83%,P<0.001),the superficial(44.08%±5.46%vs 51.28%±2.85%,P<0.001)and the deep(45.13%±8.55%vs 54.20%±5.44%,P<0.001)vascular plexus.There was a significant difference in peripapillary VD between glaucomatous and OHT eyes(44.35%±6.78%vs 49.86%±2.45%,P<0.001).The OHT group featured a lower superficial(48.06%±4.32%vs 51.28%±2.85%,P=0.027)and deep plexus(48.70%±5.99%vs 54.20%±5.44%,P=0.013)whole image vessel density(wiVD)than did the control group.The average macular superficial plexus wiVD was significantly lower in eyes with PXG than in eyes with POAG(42.22%±5.36%vs 46.54%±5.56%,P=0.046).CONCLUSION:OCTA can measure reduced peripapillary and macular VD in eyes with glaucoma and OHT,and these results are correlated to functional and structural glaucomatous alterations.Peripapillary and macular superficial plexus VD is lower in eyes with PXG than in eyes with POAG.Furthermore,the OHT eyes demonstrate impaired macular vasculature in both superficial and deep plexus.
基金supported by the National Natural Science Foundation of China(No.42274189)the Project of Science and Technology of Shaanxi(No.2021JM-395).
文摘Pancharatnam–Berry(PB)phase metasurface,as a special class of gradient metasurfaces,has been paid much attention owing to the robust performance for phase control of circularly polarized waves.Herein,we present an element-based polarizer for the first step,which enables the incident electromagnetic waves into the cross-polarized waves with the relative bandwidth of 71%,and the polarization conversion ratio exceeds 90%at 6.9–14.5 GHz.Then an eight-elements coding polarizer based on the PB phase is presented for the applications on beam control and radar cross section reduction.The simulated values indicate that the reduction of radar cross section is more than 10 dB at 6–16 GHz.Our work reveals the availability of manipulating the waves,beamforming in communication systems and electromagnetic stealth,and so on.
文摘According to the regulations of the People＇s Republic of China national standard as the basis, on the part of chemical industry product quality inspection and analysis of the implementation of computer management has developed a set of software applications, the software in chemical products quality inspection and analysis of the means of management is an innovation. The software functions, can automatically process data, judge the product grade, quality analysis, objective and fair, convenient, fast, accurate, stable, practical, and easy to popularize.
文摘Erratum to Nano Research 2022,15(10):9092-9104 https://doi.org/10.1007/s12274-022-4544-7 Figure 9 was unfortunately mistakenly typeset.This error did not affect any of the conclusions from the published paper.
基金financially supported by the National Natural Science Foundation of China(5217130394)the Natural Science Foundation of Shaanxi(2019KJXX-099,2020YZ0037,2019JLZ-09 and 2019QYPY-194)+2 种基金the Fundamental Research Funds for the Central Universities(3102019JC005)Key R&D Program of Shaanxi(No.2019ZDLGY04-05)the Development and Industrialization Fund(2020KJRC0120)。
文摘The practical deployment of metallic anodes in the energy-dense batteries is impeded by the thermodynamically unstable interphase in contact with the aprotic electrolyte,structural collapse of the substrates as well as their insufficient affinity toward the metallic deposits.Herein,the mechanical flexible,lightweight(1.2 mg cm^(−2))carbon nanofiber scaffold with the monodispersed,ultrafine Sn_(4)P_(3) nanoparticles encapsulation(Sn_(4)P_(3)NPs@CNF)is proposed as the deposition substrate toward the high-areal-capacity sodium loadings up to 4 mAh cm^(−2).First-principles calculations manifest that the alloy intermediates,namely the Na_(15)Sn_(4) and Na_(3)P matrix,exhibit the intimate Na affinity as the“sodiophilic”sites.Meanwhile,the porous CNF regulates the heterogeneous alloying process and confines the deposit propagation along the nanofiber orientation.With the precise control of pairing mode with the NaVPO4F cathode(8.7 mg cm^(−2)),the practical feasibility of the Sn_(4)P_(3) NPs@CNF anode(1^(*)Na excess)is demonstrated in 2 mAh single-layer pouch cell prototype,which achieves the 95.7%capacity retention for 150 cycles at various mechanical flexing states as well as balanced energy/power densities.
基金supported by the National Natural Science Foundation of China(No.41772260)the Science and Technology Programs of Department of Natural Resources of Zhejiang Province,China(No.2020006)the Open Project of Technology Innovation Center for Ecological Evaluation and Remediation of Agricultural Land in Plain Area,MNR(No.ZJGCJ202001)。
文摘Selenium(Se)is an essential micronutrient for lives.Indigenous microbial communities play an important role on Se geochemistry in soils.In this study,the microbial community composition and functions of 53 soil samples were investigated using high-throughput sequencing.Samples were divided into 3 groups with different farming types based on the measured geochemical parameters and microbial functional structures.Results indicated that putative Se related bacteria Bacillus,Dyella,Paenibacillus,Burkholderia and Brevibacillus were dominant in dryland plantation soils which were characterized with higher available Se and low contents of H_(2)O,total organic carbon(TOC),NH_(4)^(+) and NO_(2)^(-).In contrast,the putative denitrifier Pseudomonas dominated in flooded paddy soils with higher TOC,NO_(3)^(-) and organic Se,whereas genera Rhizobium,Nitrosospira,and Geobacter preferred woodland soils with higher oxidation-reduction potential(ORP),pH,NH_(4)^(+) and Fe.Farming patterns resulted in distinct geochemical parameters including moisture,pH,ORP,TOC,and contents of soluble Fe,NO_(2)^(-) and NH_(4)^(+),shaping the microbial communities,which in turn affected Se forms in soils.This study provides a valuable insight into understanding of Se biogeochemistry in soils and prospective strategy for Se-rich agriculture production.
基金supported by Agricultural Science and Technology Innovation Program of Chinese Academy of Agricultural Sciencesthe earmarked fund of China Agricultural Research System of China(CARS-15-11).
文摘Background Potassium(K)is an essential nutrient for plant growth and development.However,plant fertilization ignoring the soil K level is very likely to cause excessive fertilizer use,and further arouse a series of side effects.This study investigated the response of cotton growth to different soil K levels and the uptake of major nutrients,aiming to evaluate the appropriate K supply level for cotton growth.Using a random block design with 6 soil K levels,we conducted 18 micro-zones field experiments over two continuous years.The soil available K concentration of each treatment was K1(99.77-100.90 mg·kg^(-1)),K2(110.90-111.26 mg·kg^(-1)),K3(123.48-128.88 mg·kg^(-1)),K4(140.13-145.10 mg·kg^(-1)),K5(154.43-155.38 mg·kg^(-1)),and K6(165.77-168.75 mg·kg^(-1)).Cotton nutrient contents,soil nutrient contents,accumulation and distribution of dry matter in cotton were determined,and the relationships between K content in soil and plants and dry matter accumulation were analyzed.Results The soil K content had a significantly positive relationship with dry matter and K accumulation in cotton plants.There were significant differences in dry matter accumulation,single-plant seed cotton yield,mineral nutrient uptake and the proportion of K accumulation in reproductive organs among different soil K levels.The results showed that there was significant difference between K4 and lower K level treatments(K1 and K2),but no significant difference between K4 and higher K level treatments(K5 and K6)in dry matter,single-plant seed cotton yield,or accumulation,distribution and seed cotton production efficiency of N,P and K.Conclusion The soil K level of K4 was able to provide sufficient K for cotton growth in our experiment.Therefore,when the soil K level reached 140.13 mg·kg^(-1),further increasing the soil K concentration no longer had a significant positive effect on cotton growth.
基金the Natural Science Foundation of Hebei Province(No.H2019206309),China.
文摘Osteosarcoma(OS)is the most common primary bone tumor in children and adolescents.It is an aggressive tumor with a tendency to spread to the lung,which is the most common site of metastasis.Patients with advanced OS with metastases have poor prognoses despite the application of chemotherapy,thus highlighting the need for novel therapeutic targets.The tumor microenvironment(TME)of OS is confirmed to be essential for and supportive of tumor growth and dissemination.The immune component of the OS microenvironment is mainly composed of tumor-associated macrophages(TAMs).In OS,TAMs promote tumor growth and angiogenesis and upregulate the cancer stem cell-like phenotype.However,TAMs inhibit the metastasis of OS.Therefore,much attention has been paid to investigating the mechanism of TAMs in OS development and the progression of immunotherapy for OS.In this article,we aim to summarize the roles of TAMs in OS and the major findings on the application of TAMs in OS treatment.
基金This work was funded by the National Natural Science Foundation of China(Nos.21874011,91859123,and 32101140)the National Science Fund for Distinguished Young Scholars(No.22025401)+2 种基金the China Postdoctoral Science Foundation(No.2020M680396)China Postdoctoral Science Foundation(Nos.2021TQ0037 and 2021M690405)The National Natural Science Foundation of China(No.21904012)。
文摘Thylakoid(Tk)membranes are of unique superiority in photodynamic therapy(PDT)because they not only carry abundant chlorophylls containing photosensitizer porphyrin but also can produce O_(2).However,the current therapeutic performance of Tk is dramatically limited because of their poor tumor targeting and inefficient O_(2) production.Here,we report an immunomodulatory bio-nanovesicle of Tk membranes fused with M1 macrophage-derived extracellular vesicles(M1 EV)for efficient PDT of tumors.The hybrid nanovesicle Tk@M1 was prepared by squeezing the Tk membranes of spinach with M1 EV.The systemic study confirmed that Tk@M1 can not only actively accumulate in tumors but also effectively regulate the inactive immune microenvironment of tumors.Such activated"hot"tumors significantly enhance the PDT efficacy of Tk@M1 attributed to the increased O_(2) from catalase catalyzed decomposition of augmented H_(2)O_(2),providing a novel idea about constructing natural systems for effective tumor treatment.
