Field trials were performed to evaluate various techniques for measuring spray deposition and aerial drift during spray application to paddy field.The application of a spraying agent containing the fluorescent dye Rho...Field trials were performed to evaluate various techniques for measuring spray deposition and aerial drift during spray application to paddy field.The application of a spraying agent containing the fluorescent dye Rhodamine-B was applied by an unmanned aerial vehicle(UAV)which flew at a height of 5 m,a speed of 3 m/s,and the wind speed of 3 m/s.The results showed that because the downdraft produced by a helicopter rotor increased the penetrability of crops,there is a higher deposition on the upper layer and the under layer than the traditional spraying.The average deposition on the upper layer accounts for 28% of the total spraying,the deposition on the under layer accounts for 26% of the total spraying.The deposition on the under layer takes up 92.8% of the deposition on the upper layer.Droplets drift data showed that the drift of non-target area took up 12.9% of the total liquid spray.The 90% drifting droplets were located within a range of 8 m of the target area;the drift quantity was almost zero at a distance of 50 m away from the treated area.展开更多
Recent advances in systemic and locoregional treatments for patients with unresectable or advanced hepatocellular carcinoma(HCC)have resulted in improved response rates.This has provided an opportunity for selected pa...Recent advances in systemic and locoregional treatments for patients with unresectable or advanced hepatocellular carcinoma(HCC)have resulted in improved response rates.This has provided an opportunity for selected patients with initially unresectable HCC to achieve adequate tumor downstaging to undergo surgical resection,a‘conversion therapy’strategy.However,conversion therapy is a new approach to the treatment of HCC and its practice and treatment protocols are still being developed.Review the evidence for conversion therapy in HCC and develop consensus statements to guide clinical practice.Evidence review:Many research centers in China have accumulated significant experience implementing HCC conversion therapy.Preliminary findings and data have shown that conversion therapy represents an important strategy to maximize the survival of selected patients with intermediate stage to advanced HCC;however,there are still many urgent clinical and scientific challenges for this therapeutic strategy and its related fields.In order to summarize and learn from past experience and review current challenges,the Chinese Expert Consensus on Conversion Therapy for Hepatocellular Carcinoma(2021 Edition)was developed based on a review of preliminary experience and clinical data from Chinese and non-Chinese studies in this field and combined with recommendations for clinical practice.Sixteen consensus statements on the implementation of conversion therapy for HCC were developed.The statements generated in this review are based on a review of clinical evidence and real clinical experience and will help guide future progress in conversion therapy for patients with HCC.展开更多
Deposition of the histone variant H2A.Z at gene bodies regulates transcription by modifying chromatin accessibility in plants. However, the role of H2A.Z enrichment at the promoter and enhancer regions is unclear, and...Deposition of the histone variant H2A.Z at gene bodies regulates transcription by modifying chromatin accessibility in plants. However, the role of H2A.Z enrichment at the promoter and enhancer regions is unclear, and how H2A.Z interacts with other mechanisms of chromatin modification to regulate gene expression remains obscure. Here, we mapped genome-wide H2A.Z, H3K4me3, H3K27me3, Pol II, and nucleosome occupancy in Arabidopsis inflorescence. We showed that H2A.Z preferentially associated with H3K4me3 at promoters, while it was found with H3K27me3 at enhancers, and that H2A.Z deposition negatively correlated with gene expression. In addition, we demonstrated that H2A.Z represses gene expression by establishing low gene accessibility at ＋1 nucleosome and maintaining high gene accessibility at -1 nucleosome. We further showed that the high measures of gene responsiveness correlate with the H2A.Z-associated closed ＋1 nucleosome structure. Moreover, we found that H2A.Z represses enhancer activity by promoting H3K27me3 and preventing H3K4me3 histone modifications. This study provides a framework for future studies of H2A.Z functions and opens up new aspects for decoding the interplay between chromatin modification and histone variants in transcrip- tional control.展开更多
Small unmanned aerial vehicle(UAV)pesticide application technology is developing rapidly in China.However,the spray efficiency of UAV sprayer is not stable,one important reason is that the lack of specialized aviation...Small unmanned aerial vehicle(UAV)pesticide application technology is developing rapidly in China.However,the spray efficiency of UAV sprayer is not stable,one important reason is that the lack of specialized aviation nozzle.Rotary cup atomizer is not easily to be blocked and has broad application foreground in UAV spray.In order to obtain good spraying quality and narrow droplet spectrum aviation spraying centrifugal nozzle,the impacts of rotary cup atomizer structural parameters on atomization property were studied.In this research,a centrifugal atomization test device was designed,on which a frequency converter was used to adjust the rotary speed,and a return valve was used to stabilize the flow rate and pressure of spray liquid.The droplet volume medium diameter(VMD)and droplet spectrum relative width(SRW)were tested by using laser particle analyzer and particle analysis system.The analysis results of variance and quadratic regression orthogonal test were used to optimize the structural parameters of rotary cup atomizer.The influences of rotary cup atomizer structural parameters on atomization property,such as groove shape,diameter,teeth number,cone angle and height were evaluated and analyzed by conducting single-factor test.The results showed that:the best optimized rotary groove shape was square,diameter and teeth number had significant effects on droplet VMD and SRW,while cone angle had no effect on the droplet VMD and SRW,height affected droplet VMDbut did not affect droplet SRW.Therefore,diameter and teeth number were selected as the variables of quadratic regression orthogonal test,droplet VMD and SRW regression model was established by using response surface analysis method.The optimized structural parameters respectively were:groove shape square,cone angle 60°,height 20 mm,diameter 61.5 mm and teeth number 149.Droplet VMD and SRW simulation value respectively were 200μm and 0.562.The differences between simulation value and test value were 0.68%and 9.90%respectively,indicating that the regression m展开更多
Connectome mapping studies have documented a principal primary-to-transmodal gradient in the adult brain network,capturing a functional spectrum that ranges from perception and action to abstract cognition.However,how...Connectome mapping studies have documented a principal primary-to-transmodal gradient in the adult brain network,capturing a functional spectrum that ranges from perception and action to abstract cognition.However,how this gradient pattern develops and whether its development is linked to cognitive growth,topological reorganization,and gene expression profiles remain largely unknown.Using longitudinal resting-state functional magnetic resonance imaging data from 305 children(aged 6-14 years),we describe substantial changes in the primary-to-transmodal gradient between childhood and adolescence,including emergence as the principal gradient,expansion of global topography,and focal tuning in primary and default-mode regions.These gradient changes are mediated by developmental changes in network integration and segregation,and are associated with abstract processing functions such as working memory and expression levels of calcium ion regulated exocytosis and synaptic transmission-related genes.Our findings have implications for understanding connectome maturation principles in normal development and developmental disorders.展开更多
Engineering cost‐effective catalysts with exceptional performance for theelectrochemical oxygen evolution reaction (OER) remains crucial for theaccelerated development of renewable energy techniques, and especially s...Engineering cost‐effective catalysts with exceptional performance for theelectrochemical oxygen evolution reaction (OER) remains crucial for theaccelerated development of renewable energy techniques, and especially so,given the pivotal role of OER in water electrolysis. On the basis of the metalnodes (clusters) and organic linkers, metal‐organic frameworks (MOFs) andtheir derivatives are rapidly gaining ground in the fabrication of electrocatalysts,with promising catalytic activity and sound durability in OER, thanksto their controllable pore structures, abundant unsaturated active sites of metalion, extensive specific surface area, as well as easily functionalized/modifiedsurfaces. This review presents an in‐depth understanding of the establishedprogress of MOFs‐derived materials for OER electrocatalysis. The materialdesigning strategies of the pristine, monometallic, and multimetallic MOFsbasedcatalysts are summarized to indicate the infinite possibilities of themorphology and the composition of MOF‐derived materials. While emphasisis laid on the essential features of MOF‐derived materials for the electrocatalysisof the corresponding reactions, insights about the applications in OERare discussed. Finally, this paper is concluded by presenting challengesand perspectives for MOF‐derived materials’ future applications in OERelectrocatalysis.展开更多
The uncontrollable dendrites growth and intricately water-induced side reactions occurred on zinc anode leads to safety issues and poor electrochemical kinetics,which largely limit the widespread application of zinc-i...The uncontrollable dendrites growth and intricately water-induced side reactions occurred on zinc anode leads to safety issues and poor electrochemical kinetics,which largely limit the widespread application of zinc-ion batteries(ZIBs).Herein,ethylenediaminetetraacetic acid disodium salt(EDTA-2Na)is utilized as an electrolyte additive to strengthen the reversibility and cycling stability of zinc anode.Experimental results and theoretical calculation demonstrate that the EDTA-2Na presents a much stronger coordination with Zn^(2+)when comparing with H_(2)O molecular,implying the EDTA-2Na is capable to enter the solvation shell of[Zn(OH_(2))_(6)]^(2+)and coordinate with Zn^(2+)ions,thus achieving a flat and smooth zinc deposition with less by-products(Zn_(4)SO_(4)(OH)6·xH_(2)O and H_(2)).Consequently,the zinc symmetric battery with EDTA-2Na additive delivers an excellent cycling stability up to 1800 h under current density of 1 mA cm^(-2),and the hydrogen evolution reaction(HER),corrosion,by-product issues are significantly inhibited.Moreover,the rate performance and stability of coin-type and pouch-type Zn||MnO2/graphite batteries are significantly boosted via EDTA-2Na additive(248 mAh g^(-1)at 0.1 A g^(-1),81.3%after 1000 cycles at a A g^(-1)).This kind of electrolyte additive with chelation and desolvation functions shed lights on strategies of improving zinc anode stability for further application of ZIBs.展开更多
Objective： Accurate estimation of lymph node metastasis （LNM） in intramucosal gastric cancer is essential to select less invasive treatment options and even avoid surgery. The aim of this study was to evaluate comb...Objective： Accurate estimation of lymph node metastasis （LNM） in intramucosal gastric cancer is essential to select less invasive treatment options and even avoid surgery. The aim of this study was to evaluate combined clinicopathological features to predict the presence of LNM. Methods： A retrospective review of data from 386 intramucosaL gastric cancer patients who underwent gastrectomy with extended lymphadenectomy from 2003 to 2010 was conducted. The mutual relation between clinicopathological characteristics and LNM was analyzed. Results： LNM was detected in 40 （10.4%） of the 386 patients. Histological typeand vascular or lymphatic invasion presence showed a positive correlation with LNM occurrence by univariate analysis. Multivariate analysis revealed that histological type was the only factor associated with LNM. Combined clinicopathologic characteristics would be more predictable for LNM. We found no LNM when we used combined clinicopathological characteristics conforming to Japanese absolute indications for endoscopic therapy. The LNM rate was as high as 8.7% when Japanese expanded criteria were used. Univariate analysis in cancer conformity to expand endoscopic submucosal dissection （ESD） indication also revealed that the undifferential type was the only significant factor for LNM. Conclusions： It was possible to predict intramucosal gastric cancer cases without LNM using combined clinicopathological characteristic analysis. Extended indication for ESD should be cautiously used for intramucosal gastric cancer patients.展开更多
基金Special Fund for Agro-scientific Research in the Public Interest(201203025)by Ministry of Agriculture,Chinathe National High Technology Research and Development Program of China(SS2013AA100303).
文摘Field trials were performed to evaluate various techniques for measuring spray deposition and aerial drift during spray application to paddy field.The application of a spraying agent containing the fluorescent dye Rhodamine-B was applied by an unmanned aerial vehicle(UAV)which flew at a height of 5 m,a speed of 3 m/s,and the wind speed of 3 m/s.The results showed that because the downdraft produced by a helicopter rotor increased the penetrability of crops,there is a higher deposition on the upper layer and the under layer than the traditional spraying.The average deposition on the upper layer accounts for 28% of the total spraying,the deposition on the under layer accounts for 26% of the total spraying.The deposition on the under layer takes up 92.8% of the deposition on the upper layer.Droplets drift data showed that the drift of non-target area took up 12.9% of the total liquid spray.The 90% drifting droplets were located within a range of 8 m of the target area;the drift quantity was almost zero at a distance of 50 m away from the treated area.
文摘Recent advances in systemic and locoregional treatments for patients with unresectable or advanced hepatocellular carcinoma(HCC)have resulted in improved response rates.This has provided an opportunity for selected patients with initially unresectable HCC to achieve adequate tumor downstaging to undergo surgical resection,a‘conversion therapy’strategy.However,conversion therapy is a new approach to the treatment of HCC and its practice and treatment protocols are still being developed.Review the evidence for conversion therapy in HCC and develop consensus statements to guide clinical practice.Evidence review:Many research centers in China have accumulated significant experience implementing HCC conversion therapy.Preliminary findings and data have shown that conversion therapy represents an important strategy to maximize the survival of selected patients with intermediate stage to advanced HCC;however,there are still many urgent clinical and scientific challenges for this therapeutic strategy and its related fields.In order to summarize and learn from past experience and review current challenges,the Chinese Expert Consensus on Conversion Therapy for Hepatocellular Carcinoma(2021 Edition)was developed based on a review of preliminary experience and clinical data from Chinese and non-Chinese studies in this field and combined with recommendations for clinical practice.Sixteen consensus statements on the implementation of conversion therapy for HCC were developed.The statements generated in this review are based on a review of clinical evidence and real clinical experience and will help guide future progress in conversion therapy for patients with HCC.
文摘Deposition of the histone variant H2A.Z at gene bodies regulates transcription by modifying chromatin accessibility in plants. However, the role of H2A.Z enrichment at the promoter and enhancer regions is unclear, and how H2A.Z interacts with other mechanisms of chromatin modification to regulate gene expression remains obscure. Here, we mapped genome-wide H2A.Z, H3K4me3, H3K27me3, Pol II, and nucleosome occupancy in Arabidopsis inflorescence. We showed that H2A.Z preferentially associated with H3K4me3 at promoters, while it was found with H3K27me3 at enhancers, and that H2A.Z deposition negatively correlated with gene expression. In addition, we demonstrated that H2A.Z represses gene expression by establishing low gene accessibility at ＋1 nucleosome and maintaining high gene accessibility at -1 nucleosome. We further showed that the high measures of gene responsiveness correlate with the H2A.Z-associated closed ＋1 nucleosome structure. Moreover, we found that H2A.Z represses enhancer activity by promoting H3K27me3 and preventing H3K4me3 histone modifications. This study provides a framework for future studies of H2A.Z functions and opens up new aspects for decoding the interplay between chromatin modification and histone variants in transcrip- tional control.
基金the National Key Research and Development Plan(No.2016YFD0200702)2012 Foundation Project of Technology Innovation for Graduate in Jiangsu Province of China(No.CXLX12_0658)+4 种基金Special Fund for Agro-scientific Research in the Public Interest(No.201203025)National High Technology Research and Development Program of China(863 program,2013AA102303)Synergistic Innovation Center of Modern Agricultural Equipment and Technology in Jiangsu Province(NZXT01201403)Agriculture Intelligent Equipment and Technology Research Key Laboratory Open Research Topic in Jiangsu province(NZ201005)the Natural Science Foundation of Jiangsu Province,China(BK 20151074).
文摘Small unmanned aerial vehicle(UAV)pesticide application technology is developing rapidly in China.However,the spray efficiency of UAV sprayer is not stable,one important reason is that the lack of specialized aviation nozzle.Rotary cup atomizer is not easily to be blocked and has broad application foreground in UAV spray.In order to obtain good spraying quality and narrow droplet spectrum aviation spraying centrifugal nozzle,the impacts of rotary cup atomizer structural parameters on atomization property were studied.In this research,a centrifugal atomization test device was designed,on which a frequency converter was used to adjust the rotary speed,and a return valve was used to stabilize the flow rate and pressure of spray liquid.The droplet volume medium diameter(VMD)and droplet spectrum relative width(SRW)were tested by using laser particle analyzer and particle analysis system.The analysis results of variance and quadratic regression orthogonal test were used to optimize the structural parameters of rotary cup atomizer.The influences of rotary cup atomizer structural parameters on atomization property,such as groove shape,diameter,teeth number,cone angle and height were evaluated and analyzed by conducting single-factor test.The results showed that:the best optimized rotary groove shape was square,diameter and teeth number had significant effects on droplet VMD and SRW,while cone angle had no effect on the droplet VMD and SRW,height affected droplet VMDbut did not affect droplet SRW.Therefore,diameter and teeth number were selected as the variables of quadratic regression orthogonal test,droplet VMD and SRW regression model was established by using response surface analysis method.The optimized structural parameters respectively were:groove shape square,cone angle 60°,height 20 mm,diameter 61.5 mm and teeth number 149.Droplet VMD and SRW simulation value respectively were 200μm and 0.562.The differences between simulation value and test value were 0.68%and 9.90%respectively,indicating that the regression m
基金supported by the National Natural Science Foundation of China(31830034,82021004,81620108016,31221003,31521063,81671767,82071998,81971690,32130045,and 61761166004)Changjiang Scholar Professorship Award(T2015027)+3 种基金the National Key Research and Development Project of China(2018YFA0701402)Beijing Nova Program(Z191100001119023)the Beijing Brain Initiative of Beijing Municipal Science&Technology Commission(Z181100001518003)the Fundamental Research Funds for the Central Universities(2020NTST29)。
文摘Connectome mapping studies have documented a principal primary-to-transmodal gradient in the adult brain network,capturing a functional spectrum that ranges from perception and action to abstract cognition.However,how this gradient pattern develops and whether its development is linked to cognitive growth,topological reorganization,and gene expression profiles remain largely unknown.Using longitudinal resting-state functional magnetic resonance imaging data from 305 children(aged 6-14 years),we describe substantial changes in the primary-to-transmodal gradient between childhood and adolescence,including emergence as the principal gradient,expansion of global topography,and focal tuning in primary and default-mode regions.These gradient changes are mediated by developmental changes in network integration and segregation,and are associated with abstract processing functions such as working memory and expression levels of calcium ion regulated exocytosis and synaptic transmission-related genes.Our findings have implications for understanding connectome maturation principles in normal development and developmental disorders.
基金This study was supported by the Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(NRF‐2018R1D1A1B07051249)Nano Material Technology Development Program(NRF‐2015M3A7B6027970)+1 种基金the Science and Technology Amicable Relationships(STAR)Program(NRF‐2019K1A3A1A21031052)of MSIT/NRFThis study was also supported by the Center for Integrated Smart Sensors funded by the Ministry of Science,ICT and Future Planning,Republic of Korea,as a Global Frontier Project(CISS‐2012M3A6A6054186).
文摘Engineering cost‐effective catalysts with exceptional performance for theelectrochemical oxygen evolution reaction (OER) remains crucial for theaccelerated development of renewable energy techniques, and especially so,given the pivotal role of OER in water electrolysis. On the basis of the metalnodes (clusters) and organic linkers, metal‐organic frameworks (MOFs) andtheir derivatives are rapidly gaining ground in the fabrication of electrocatalysts,with promising catalytic activity and sound durability in OER, thanksto their controllable pore structures, abundant unsaturated active sites of metalion, extensive specific surface area, as well as easily functionalized/modifiedsurfaces. This review presents an in‐depth understanding of the establishedprogress of MOFs‐derived materials for OER electrocatalysis. The materialdesigning strategies of the pristine, monometallic, and multimetallic MOFsbasedcatalysts are summarized to indicate the infinite possibilities of themorphology and the composition of MOF‐derived materials. While emphasisis laid on the essential features of MOF‐derived materials for the electrocatalysisof the corresponding reactions, insights about the applications in OERare discussed. Finally, this paper is concluded by presenting challengesand perspectives for MOF‐derived materials’ future applications in OERelectrocatalysis.
基金supported from the National Research Council of Thailand(NRCT):NRCT-RSA63001-19Second Century Fund(C2F),Chulalongkorn University.
文摘The uncontrollable dendrites growth and intricately water-induced side reactions occurred on zinc anode leads to safety issues and poor electrochemical kinetics,which largely limit the widespread application of zinc-ion batteries(ZIBs).Herein,ethylenediaminetetraacetic acid disodium salt(EDTA-2Na)is utilized as an electrolyte additive to strengthen the reversibility and cycling stability of zinc anode.Experimental results and theoretical calculation demonstrate that the EDTA-2Na presents a much stronger coordination with Zn^(2+)when comparing with H_(2)O molecular,implying the EDTA-2Na is capable to enter the solvation shell of[Zn(OH_(2))_(6)]^(2+)and coordinate with Zn^(2+)ions,thus achieving a flat and smooth zinc deposition with less by-products(Zn_(4)SO_(4)(OH)6·xH_(2)O and H_(2)).Consequently,the zinc symmetric battery with EDTA-2Na additive delivers an excellent cycling stability up to 1800 h under current density of 1 mA cm^(-2),and the hydrogen evolution reaction(HER),corrosion,by-product issues are significantly inhibited.Moreover,the rate performance and stability of coin-type and pouch-type Zn||MnO2/graphite batteries are significantly boosted via EDTA-2Na additive(248 mAh g^(-1)at 0.1 A g^(-1),81.3%after 1000 cycles at a A g^(-1)).This kind of electrolyte additive with chelation and desolvation functions shed lights on strategies of improving zinc anode stability for further application of ZIBs.
文摘Objective： Accurate estimation of lymph node metastasis （LNM） in intramucosal gastric cancer is essential to select less invasive treatment options and even avoid surgery. The aim of this study was to evaluate combined clinicopathological features to predict the presence of LNM. Methods： A retrospective review of data from 386 intramucosaL gastric cancer patients who underwent gastrectomy with extended lymphadenectomy from 2003 to 2010 was conducted. The mutual relation between clinicopathological characteristics and LNM was analyzed. Results： LNM was detected in 40 （10.4%） of the 386 patients. Histological typeand vascular or lymphatic invasion presence showed a positive correlation with LNM occurrence by univariate analysis. Multivariate analysis revealed that histological type was the only factor associated with LNM. Combined clinicopathologic characteristics would be more predictable for LNM. We found no LNM when we used combined clinicopathological characteristics conforming to Japanese absolute indications for endoscopic therapy. The LNM rate was as high as 8.7% when Japanese expanded criteria were used. Univariate analysis in cancer conformity to expand endoscopic submucosal dissection （ESD） indication also revealed that the undifferential type was the only significant factor for LNM. Conclusions： It was possible to predict intramucosal gastric cancer cases without LNM using combined clinicopathological characteristic analysis. Extended indication for ESD should be cautiously used for intramucosal gastric cancer patients.
