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MUTS-Based Cooperative Target Stalking for A Multi-USV System 被引量:1
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作者 Chengcheng Wang Yulong Wang +1 位作者 Qing-Long Han Yunkai Wu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第7期1582-1592,共11页
This paper is concerned with the cooperative target stalking for a multi-unmanned surface vehicle(multi-USV)system.Based on the multi-agent deep deterministic policy gradient(MADDPG)algorithm,a multi-USV target stalki... This paper is concerned with the cooperative target stalking for a multi-unmanned surface vehicle(multi-USV)system.Based on the multi-agent deep deterministic policy gradient(MADDPG)algorithm,a multi-USV target stalking(MUTS)algorithm is proposed.Firstly,a V-type probabilistic data extraction method is proposed for the first time to overcome shortcomings of the MADDPG algorithm.The advantages of the proposed method are twofold:1)it can reduce the amount of data and shorten training time;2)it can filter out more important data in the experience buffer for training.Secondly,in order to avoid the collisions of USVs during the stalking process,an action constraint method called Safe DDPG is introduced.Finally,the MUTS algorithm and some existing algorithms are compared in cooperative target stalking scenarios.In order to demonstrate the effectiveness of the proposed MUTS algorithm in stalking tasks,mission operating scenarios and reward functions are well designed in this paper.The proposed MUTS algorithm can help the multi-USV system avoid internal collisions during the mission execution.Moreover,compared with some existing algorithms,the newly proposed one can provide a higher convergence speed and a narrower convergence domain. 展开更多
关键词 Cooperative target stalking improved deep reinforcement learning multi-unmanned surface vehicle(multi-USV)systems V-type probabilistic data extraction
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Stalking of Healthcare Professionals by Their Clients: The Prevalence, Motivation, and Effect
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作者 Sefa Bulut Ali Cissy Usman Thseen Nazir 《Open Journal of Medical Psychology》 2021年第2期27-35,共9页
It is proposed that healthcare professionals are prone to be stalked by their patients, but many feel ashamed to talk about it, believing that they might have done something to warrant the stalking. We undertook a rig... It is proposed that healthcare professionals are prone to be stalked by their patients, but many feel ashamed to talk about it, believing that they might have done something to warrant the stalking. We undertook a rigorous review of the literature with the primitive goal of highlighting noteworthy issues on the stalking of healthcare professionals and psychologists by their patients. Databases such as PubMed and Google Scholar were searched to collate articles and studies on the topic with the keywords “stalker, stalking, assaults, aggression, and physicians”. From the review, the prevalence rate of stalking healthcare professionals ranged between 6%</span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">-</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">53%. This huge variation was largely due to the inconsistencies in the definition of what constituted stalking. The common motives of stalkers were largely due to erotomania or misguided expectation and a sense of resentment due to service dissatisfaction. Finally, it was apparently right to conclude that, medical doctors or healthcare professionals are at risk of being stalked on the grounds of service dissatisfaction, and mismanagement of treatment processes resulting in physical or perceived client injuries. Whereas psychologists and other psychiatrists are more prone to be stalked due to erotomaniac reasons. 展开更多
关键词 stalking Erotomania Misguided Expectation RESENTMENT Healthcare Professionals
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STRANGER DANGER——DISTURBING"HISSED CONNECTIONS"VIDEO EXPOSES A LACK OF STALKING PROTECTION
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《The World of Chinese》 2019年第1期8-9,共2页
"If I can't use normal channels,I'll [find her]some other was" Mr.Sun vowed to the camera,alarming millions of viewers who've followed the story of his obsession with a fellow shopper at a Beijin... "If I can't use normal channels,I'll [find her]some other was" Mr.Sun vowed to the camera,alarming millions of viewers who've followed the story of his obsession with a fellow shopper at a Beijing bookstore via a series of viral Pear Video cfips since mid-December. 展开更多
关键词 STRANGER DANGER "HISSED CONNECTIONS" stalking
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Identification of key enzymes in lignocellulose biosynthesis from dynamic observations in maize stalks
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作者 Xiaoxu Zhan Fanlei Kong +6 位作者 Qinlin Liu Tianqiong Lan Fan Liu Xinglong Wang Xia Du Xiang Chen Jichao Yuan 《The Crop Journal》 SCIE CSCD 2024年第6期1754-1764,共11页
Maize stalk lignin and cellulose contents are linked to lodging resistance,disease resistance,feed quality and ethanol conversion efficiency.After the six-leaf stage of maize(V6),these constituents are biosynthesized ... Maize stalk lignin and cellulose contents are linked to lodging resistance,disease resistance,feed quality and ethanol conversion efficiency.After the six-leaf stage of maize(V6),these constituents are biosynthesized and accumulated under the control of related enzymes and genes.However,the key enzymes,critical MYB transcription factors,and their dynamic alterations pattern under natural field circumstances are still unknown.Hence,we selected five cultivars with significant differences in lignocellulose content and lodging resistance as testing materials,performed field experiments for two years,and investigated the dynamics of lignin and cellulose content,related enzyme concentrations,and gene expression levels in the 3^(rd) and 5^(th) internodes above the ground after V6.The results showed that lignin and cellulose content increased after V6,stabilizing during the silking stage.This study identified COMT(caffeic acid 3-Omethyltransferase),TAL(tyrosine ammonia-lyase)and PAL(phenylalanine ammonia-lyase)as the key enzymes of lignin biosynthesis,while ZmCOMT,ZmCesA10 and ZmCesA8 were identified as essential genes.ZmMYB8,ZmMYB31 and ZmMYB39 were involved in regulating the expression of genes related to lignin synthesis,with ZmMYB31 potentially acting as a key negative regulator,while ZmMYB39 and ZmMYB8 acting as positive regulators.The study also found that around 14 d after V6 was a critical stage for regulating lignocellulose synthesis in the 3^(rd) to 5^(th) basal internode.This provides a theoretical foundation for developing regulatory techniques and breeding new cultivars to enhance lodging and disease resistance as well as the utility of maize stalks. 展开更多
关键词 LIGNIN CELLULOSE BIOSYNTHESIS Key enzyme Maize stalk
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Genome-wide association mapping and genomic prediction of stalk rot in two mid-altitude tropical maize populations
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作者 Junqiao Song Angela Pacheco +7 位作者 Amos Alakonya Andrea S.Cruz-Morales Carlos Muoz-Zavala Jingtao Qu Chunping Wang Xuecai Zhang Felix San Vicente Thanda Dhliwayo 《The Crop Journal》 SCIE CSCD 2024年第2期558-568,共11页
Maize stalk rot reduces grain yield and quality.Information about the genetics of resistance to maize stalk rot could help breeders design effective breeding strategies for the trait.Genomic prediction may be a more e... Maize stalk rot reduces grain yield and quality.Information about the genetics of resistance to maize stalk rot could help breeders design effective breeding strategies for the trait.Genomic prediction may be a more effective breeding strategy for stalk-rot resistance than marker-assisted selection.We performed a genome-wide association study(GWAS)and genomic prediction of resistance in testcross hybrids of 677 inbred lines from the Tuxpe?o and non-Tuxpe?o heterotic pools grown in three environments and genotyped with 200,681 single-nucleotide polymorphisms(SNPs).Eighteen SNPs associated with stalk rot shared genomic regions with gene families previously associated with plant biotic and abiotic responses.More favorable SNP haplotypes traced to tropical than to temperate progenitors of the inbred lines.Incorporating genotype-by-environment(G×E)interaction increased genomic prediction accuracy. 展开更多
关键词 Maize stalk rot Genome-wide association mapping Haplotype analysis Genomic prediction G×E interaction
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Natural variation in maize gene ZmSBR1 confers seedling resistance to Fusarium verticillioides
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作者 Yunxia Song Peipei Ma +10 位作者 Jingyang Gao Chaopei Dong Zhao Wang Yifan Luan Jiafa Chen Doudou Sun Pei Jing Xuecai Zhang Weibin Song Zijian Zhou Jianyu Wu 《The Crop Journal》 SCIE CSCD 2024年第3期836-844,共9页
Maize seedling blight caused by Fusarium verticillioides is a widely occurring maize disease,but the genetics and mechanisms of resistance are not well understood.In this study,GWAS performed by MLM and 3VmrMLM identi... Maize seedling blight caused by Fusarium verticillioides is a widely occurring maize disease,but the genetics and mechanisms of resistance are not well understood.In this study,GWAS performed by MLM and 3VmrMLM identified 40 and 20 QTNs,associated with seedling blight resistance.These methods identified 49 and 36 genes,respectively.Functional verification of candidate gene ZmSBR1 identified by both methods showed that the resistance of a mutant line to seedling blight decreased by 0.37 grade points after inoculation with F.verticillioides,compared with the WT.The length of the stem rot lesion caused by F.verticillioides increased by 86%in mutant seedlings,and the relative length of the adult plant stalk rot increased by 35%in mutant plants compared to the wild type after inoculation with Fusarium graminearum.Transcriptome analysis showed that expression of defense-related genes after inoculation was down-regulated in the mutant compared to the wild type,synthesis of secondary metabolites associated with resistance was reduced,and the immune response triggered by PAMP decreased,resulting in decreased resistance of mutant maize seedlings.Candidate gene association analysis showed that most maize inbred lines carried the susceptible haplotype.A functional PCR marker was developed.The results demonstrated that ZmSBR1 conferred resistance to multiple Fusarium diseases at the seedling and adult growth stages and had important application value in breeding. 展开更多
关键词 Seedling blight Stalk rot Multiple disease resistance
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A Comprehensive Analysis of the Thermo-Chemical Properties of Sudanese Biomass for Sustainable Applications
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作者 Wadah Mohammed Zeinab Osman +1 位作者 Salah Elarabi Bertrand Charrier 《Journal of Renewable Materials》 EI CAS 2024年第4期721-736,共16页
The chemical composition and thermal properties of natural fibers are the most critical variables that determine the overall properties of the fibers and influence their processing and use in different sustainable app... The chemical composition and thermal properties of natural fibers are the most critical variables that determine the overall properties of the fibers and influence their processing and use in different sustainable applications,such as their conversion into bioenergy and biocomposites.Their thermal and mechanical properties can be estimated by evaluating the content of cellulose,lignin,and other extractives in the fibers.In this research work,the chemical composition and thermal properties of three fibers,namely bagasse,kenaf bast fibers,and cotton stalks,were evaluated to assess their potential utilization in producing biocomposites and bioenergy materials.The chemical composition analysis followed the Technical Association of the Pulp and Paper Industry Standards(TAPPI)methods.The total phenol content was quantified using the Folin-Ciocalteu method,while Fourier Transform Infrared Spectroscopy(FTIR)was employed to assess the light absorption by the bonds.To evaluate thermal stability and higher heating values,Thermogravimetric Analysis(TGA),Differential Scanning Calorimetry(DSC),and bomb calorimetry were performed.The chemical analysis revealed that bagasse contained 50.6%cellulose and 21.6%lignin,kenaf bast fibers had 58.5%cellulose and 10%lignin,and cotton stalks exhibited 40.3%cellulose and 21.3%lignin.The FTIR curves demonstrated a notable similarity among the fibers.The TGA analysis showed degradation temperatures of 321°C for bagasse,354°C for kenaf bast fibers,and 289°C for cotton stalks.The DSC analysis revealed glass transition temperatures of 81°C for bagasse,66.3°C for cotton stalks,and 64.5°C for kenaf bast fibers.The higher heating values were measured as 17.3,16.6 and 17.1 MJ/kg for bagasse,kenaf bast fibers,and cotton stalks,respectively.The three fibers have a high potential for biocomposites and bioenergy material manufacturing. 展开更多
关键词 BAGASSE kenaf bast fibers cotton stalks TGA DSC FTIR
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Determination of Physical, Mechanical and Fire Retardancy Properties of Innovative Particleboard Made from Corn Stalk (Zea mays L.) Particles
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作者 Lilik Astari Benoit Belleville +3 位作者 Kenji Umemura Alex Filkov Barbara Ozarska Robert H.Crawford 《Journal of Renewable Materials》 EI CAS 2024年第10期1729-1756,共28页
The demand for particleboard is increasing along with economic and population growth.However,two major barriers to the manufacture of particleboard are a shortage of raw materials(woodchips)and the emission of formald... The demand for particleboard is increasing along with economic and population growth.However,two major barriers to the manufacture of particleboard are a shortage of raw materials(woodchips)and the emission of formaldehyde from conventional adhesives.Agricultural by-products such as corn stalks contain an abundance of renewable lignocellulosic fiber.This study evaluates the effect of citric acid as a natural adhesive and fire retardant addition on the physical,mechanical,and fire retardancy properties of particleboards fabricated from corn stalks.A cost-effective and inorganic salt,calcium carbonate,was tested to enhance the fire retardancy.Ammonium dihydrogen phosphate was also considered as a comparative control.Particleboards with the addition of calcium carbonate was pretreated with sodium chloride.The particleboards were pressed for 10 min at 200℃.Japanese Industrial Standard JIS A 5908:2022 was used as the benchmark for the physical and mechanical tests.Fire retardancy was dynamically tested by simulating a Bushfire Attack Level of 19 kW/m^(2).The particleboard with 25 wt%citric acid had superior mechanical properties and complied with the JIS A 5908 standard for Type 13 base particleboard.Particleboard with the addition of calcium carbonate(5%and 10%)showed significantly delayed pyrolysis time. 展开更多
关键词 PARTICLEBOARD corn stalk fire retardancy citric acid mechanical properties
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Pulsatile gonadotropin-releasing hormone therapy induces spermatogenesis in pituitary stalk interruption syndrome:A case report and review of the literature
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作者 Jin-Long Xie Hai-Ying Zhu +5 位作者 Yang Dong Ping-Ping Sun Dan-Dan Qi Su-Xian Luan Yan Zhang Hua-Gang Ma 《World Journal of Clinical Cases》 SCIE 2024年第20期4348-4356,共9页
BACKGROUND Pituitary stalk interruption syndrome(PSIS)is a rare anatomical defect of the pituitary gland falling under the spectrum of holoprosencephaly phenotypes.It is characterized by a deficiency in anterior pitui... BACKGROUND Pituitary stalk interruption syndrome(PSIS)is a rare anatomical defect of the pituitary gland falling under the spectrum of holoprosencephaly phenotypes.It is characterized by a deficiency in anterior pituitary hormones,such as growth hormone,gonadotropins,and thyroid hormones.Due to the syndrome's rarity and nonspecific manifestations,there is a lack of standardized treatment strategies.Consequently,early diagnosis through imaging and on-time intervention are crucial for improving patients’outcomes.CASE SUMMARY A 30-year-old man presented with absent secondary sexual characteristics and azoospermia.Laboratory evaluation revealed a deficiency in gonadotropins,while thyroid function was mostly within normal ranges.Magnetic resonance imaging of the pituitary gland showed pituitary stalk agenesis,hypoplasia of the anterior pituitary,and ectopic posterior pituitary,leading to the diagnosis of PSIS.Initially,the patient underwent 6 mo of gonadotropin therapy without significant changes in hormone levels and secondary sexual characteristics.Pulsatile gonadotropin-releasing hormone therapy was then administered,resulting in the detection of sperm in the semen analysis within 3 mo.After 6 mo,routine semen tests showed normal semen quality.The couple faced challenges in conceiving due to abstinence and underwent three cycles of artificial insemination,which was unsuccessful.They also attempted in vitro fertilization,but unfortunately,the woman experienced a miscarriage 10 wk after the embryo transfer.CONCLUSION Early detection,accurate diagnosis,and timely treatment are crucial in improving the quality of life and fertility of PSIS patients. 展开更多
关键词 Pituitary stalk interruption syndrome Hypogonadotropic hypogonadism SPERMATOGENESIS Pulsatile gonadotropinreleasing hormone therapy Case report
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Pituitary stalk interruption syndrome complicated with liver cirrhosis:A case report
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作者 Min Chang Shi-Yu Wang +5 位作者 Zi-Yu Zhang Hong-Xiao Hao Xin-Gang Li Jing-Jing Li Yao Xie Ming-Hui Li 《World Journal of Hepatology》 2024年第11期1348-1355,共8页
BACKGROUND Pituitary stalk interruption syndrome(PSIS)is a rare disorder,often characterized by delayed growth and development,short stature,and hypogonadism as the main clinical manifestations.It is not clear whether... BACKGROUND Pituitary stalk interruption syndrome(PSIS)is a rare disorder,often characterized by delayed growth and development,short stature,and hypogonadism as the main clinical manifestations.It is not clear whether PSIS can lead to liver cirrhosis.CASE SUMMARY This paper reported a case of liver cirrhosis of unknown origin.The patient was admitted to Beijing Ditan Hospital Affiliated to Capital Medical University in November 2023.The diagnosis of PSIS complicated with liver cirrhosis was established after a series of blood tests and pituitary magnetic resonance imaging examination.CONCLUSION We also reviewed the literature from both domestic and international sources to deepen the clinical understanding of PSIS in conjunction with liver cirrhosis among medical practitioners. 展开更多
关键词 Pituitary stalk interruption syndrome Growth hormone Magnetic resonance imaging Liver cirrhosis
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Key Physical Factors Affecting Spatial-temporal Variation of Labile Organic Carbon Fractions by Biochar Driven in Mollisols Region of Northeast China
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作者 Zhao Wei Liang Fangyuan +4 位作者 Liang Ying Zhao Hongrui Hao Shuai Wang Hongyan Wang Daqing 《Journal of Northeast Agricultural University(English Edition)》 CAS 2024年第1期28-41,共14页
Biochar is widely used to improve soil physical properties and carbon sequestration. However, few studies focuse on the impact of maize stalk biochar on labile organic carbon(LOC) pool and the relationship between phy... Biochar is widely used to improve soil physical properties and carbon sequestration. However, few studies focuse on the impact of maize stalk biochar on labile organic carbon(LOC) pool and the relationship between physical properties and LOC fractions. A field positioning experiment was performed in Mollisols region of Northeast China to evaluate the influence of maize stalk biochar on the spatial distribution and temporal changes of physical properties and LOC fractions. Maize stalk biochar treatments included C1(1.5 kg·hm^(-2)), C2(3 kg·hm^(-2)), C3(15 kg·hm^(-2)), C4(30 kg·hm^(-2)), and CK(0). The results showed that maize stalk biochar increased soil water contents(SWC) and soil porosity(SP), but reduced bulk density(BD). Maize stalk biochar reduced dissolved organic carbon(DOC) contents in the 0-20 cm soil layer, ranging from 0.25 g·kg^(-1) to 0.31 g·kg^(-1) in harvest period, while increased in the 20-40 cm soil layer. In addition, the application of biochar had a significant impact on the spatial distribution and temporal change of SWC, BD, SP, DOC, hot-water extractable carbon(HWC), acid hydrolyzed organic carbon(AHC Ⅰ, Ⅱ), and readily oxidized organic carbon(ROC). High amounts of maize stalk biochar up-regulated the contents of soil organic carbon SOC, HWC, AHC Ⅰ, AHC Ⅱ, and ROC. In addition, SWC and SP were the key physical factors to affect LOC fractions. In conclusions, maize stalk biochar could improve physical properties, and then influence LOC fractions, and maize stalk biochar could be used as an organic amendment for restoring degraded soils governed by their rates of addition. 展开更多
关键词 maize stalk biochar labile organic carbon fraction Mollisols region soil physical property dissolved organic carbon
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Biomechanical Characteristics of Rape Stalks 被引量:6
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作者 吴晓强 闫鹏 +4 位作者 王鑫 曹中华 刘春利 韩彩锐 牛应泽 《Agricultural Science & Technology》 CAS 2012年第5期972-978,共7页
[Objective] To study the correlation between the biomechanical properties of rape stalks and rape stem lodging. [Method] Through axial compression tests to the stalks of 4 different rape varieties, the change rules of... [Objective] To study the correlation between the biomechanical properties of rape stalks and rape stem lodging. [Method] Through axial compression tests to the stalks of 4 different rape varieties, the change rules of maximum stem bearing ca- pacity, maximum compressive strength, elastic modulus and moment of inertia along plant height were analyzed, as well as the effect of different varieties and water contents on the biomechanical property indices of rape stalks. [Result] The maximum loads of rape stalks presented liner decrease trend along with the increase of stem height, and all reached the maximums below the height of 50 cm. The maximum stem compressive strength and elastic modulus of the 4 varieties were increased with ascending height, but in a slow rate with small change, thus the modulus of e- lasticity could be considered as unchanged. The maximum bearing capacity, maxi- mum compressive strength and elastic modulus of dry rape stalks were higher than wet stalks, indicating that the water contents of rape stalks had significant effect on their mechanical properties. According to the actual lodging situations in filed, stalks of variety No. 1 owned the worst biomechanical properties and lodging degree, while the biomechanical properties of No. 6 and F5 were better than No. 1 and No. 9, and they also had stronger lodging-resistance. [Conclusion] The study provides parameters and bases for the design of mechanized production and mechanical deep processing of crops, and can better reveal the physical natures of organisms. The methods used in this study can also be used to screen excellent crop stalks. 展开更多
关键词 Rape stalk LODGING Axial compression Plant height Biomechanical performance
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Effects of Planting Density and Nitrogen Amount on Stalk Lodging-Resistance and Yield of Summer Maize in Sichuan Basin 被引量:6
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作者 陈尚洪 陈红琳 +1 位作者 沈学善 刘定辉 《Agricultural Science & Technology》 CAS 2012年第10期2147-2151,共5页
[Objective] The experiment was conducted to explore the suitable planting density and nitrogen amount for summer maize in Sichuan Basin with the objective to provide technical reservation and scientific basis for high... [Objective] The experiment was conducted to explore the suitable planting density and nitrogen amount for summer maize in Sichuan Basin with the objective to provide technical reservation and scientific basis for high-yielding cultivation technique.[Method] A widely planted maize cultivar 'Chengdan 30' was used as experimental material to study the effects of planting density and nitrogen amount on the stalk agronomic traits,stalk lodging-resistance mechanical characters,stalk breaking percentage and yield of maize.Experiment was arranged in a two-factor split plot design with three replicates.The planting density was the main factor with three density gradients(4.5×10^4,6.0×10^4 and 7.5×10^4 plants/hm^2) and the nitrogen amount was the second factor with two different levels of nitrogen content(300 and 375 kg/hm^2).[Result] The stalk lodging-resistance and yield were affected by planting density significantly.The increase of planting density would result in an increase of internode length and decrease of internode diameter,dry matter weight of per unit stalk length,rind penetration strength and breaking resistance of 3rd and 4th basal internodes.When planting density increased from 6.0×10^4 plants/hm2 to 7.5×10^4 plants/hm^2,the stalk breaking percentage in the whole growing season increased by 17.17%,and the yield reduced by 17.58%.The interaction between planting density and nitrogen amount affected the stalk breaking percentage in the whole growing season and yield significantly.The treatment with planting density of 6.0×104 plants/hm^2 and nitrogen amount of 375 kg/hm^2 of pure N was an optimal combination,which may not only control the stalk breaking percentage of whole growing stage effectively,but also could obtain an optimum grain yield.[Conclusion] In Sichuan Basin,the appropriate planting density and nitrogen amount for summer maize were 6.0×10^4 plants/hm^2 and 375 kg/hm^2. 展开更多
关键词 Summer maize Planting density Nitrogen amount Stalk lodging resistance YIELD
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A Preliminary Study on Pollination Biology of an Endangered Orchid, Changnienia amoena, in Shennongjia 被引量:9
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作者 孙海芹 罗毅波 葛颂 《Acta Botanica Sinica》 CSCD 2003年第9期1019-1023,共5页
Changnienia amoena Chien is a monotypic species and endemic to China, and was listed on the Chinese Red Book in 1992. The species was once abundant but has become rare and endangered in recent years because of the hab... Changnienia amoena Chien is a monotypic species and endemic to China, and was listed on the Chinese Red Book in 1992. The species was once abundant but has become rare and endangered in recent years because of the habitat fragmentation and unduly commercial collections. Previous observation showed that this species has very low and even no fruit set, and the pollinators are not observed before this report. The present observation was conducted at the Shennongjia, Hubei Province during the spring of 2002. The results showed that Bombus (Diversobombus) trifasciatus Smith, B. imitator Pittion and one species of Apis visited the flowers of the orchid, but only B. tritasciatus could carry pollinaria on its body and was the legitimate pollinators of C amoena. During 113 h of observation, only nine visitations were recorded. The bumblebees mainly appeared during 12:00-15:00 during the day. Bumblebees stayed in a flower only a few seconds and never more than ten seconds. The flowers would persist in fresh for about three weeks when they were not pollinated, but 3 or 4 d after pollinated, the pollinated flowers underwent a series of color and morphological changes including stalk elongation and ovary swelling. Therefore, stalk elongation can be considered an index of fruits set. Artificial pollination indicated that C amoena is a highly self-compatible and outcrossing species, but dependent on pollinators for fruit set. Based on the field observations, we concluded that pollination system of C amoena is deceptive. The fruit set in nature is not very low (26.98% on average) compared to other deceptive orchids, which may be related to small population sizes. The number of pollinia removal is much higher than that of fruit set, indicating that there are some degrees of pollinia wasting in C amoena. 展开更多
关键词 Changnienia amoena Bombus (Diversobombus) trifasciatus deceptive pollination stalk elongation
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Effects of Feeding Corn Stalks on Economic Indicators of Tenebrio molitor 被引量:3
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作者 吉志新 温晓蕾 +6 位作者 王长青 余金咏 宋金昌 王哲 齐慧霞 胡振妍 李汉臣 《Agricultural Science & Technology》 CAS 2011年第10期1513-1516,共4页
[Objective] The study aimed at reducing the economic cost in feeding Tenebrio molitor and improving the utilization ratio of corn stalks.[Method] The effects of different proportions of corn stalks on the weigh of Ten... [Objective] The study aimed at reducing the economic cost in feeding Tenebrio molitor and improving the utilization ratio of corn stalks.[Method] The effects of different proportions of corn stalks on the weigh of Tenebrio molitor and the contents of crude protein,crude fat,Ca,P,dry matter and crude ash in the half-dry matter of Tenebrio molitor had been studied in the laboratory.[Result] Compared with the recipes of all wheat bran and pure fine fodder,feeding Tenebrio molitor by applying 30%-60% of corn stalks could significantly improve the content of crude protein in the half-dry materials of Tenebrio molitor,but it was detrimental to the improvement in weight of Tenebrio molitor and the accumulation of crude fat.To be specific,the recipe V(50% of corn stalks + 50% of fine fodder) was beneficial to the accumulation of dry matter and crude ash.The recipe VII(70% of corn stalks + 30% of fine fodder) and the recipe VIII(70% of corn stalks treated with Guangda feed leaven + 30% of fine fodder) were beneficial to the accumulation of crude protein,Ca and P.There were differences among the influences of corn stalks in different treatments on the crude protein and other nutrition indicators of Tenebrio molitor.[Conclusion] Appropriately applying corn stalks can improve the accumulation of the crude protein,crude ash,dry matter,Ca and P of Tenebrio molitor but was detrimental to the growth and development of Tenebrio molitor and the accumulation of crude fat. 展开更多
关键词 Tenebrio molitor larvae Corn stalks Nutrition indicators
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Comparison of RNA Extraction Methods of Sugarcane Stem 被引量:5
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作者 陈萍 罗挺 蔡文伟 《Agricultural Science & Technology》 CAS 2010年第3期43-46,共4页
[Objective] The study was to explore the most effective and feasible method for sugarcane stalks RNA extraction.[Method] SDS extraction method,kit extraction method and GHCL extraction method were used to extract the ... [Objective] The study was to explore the most effective and feasible method for sugarcane stalks RNA extraction.[Method] SDS extraction method,kit extraction method and GHCL extraction method were used to extract the sugarcane RNA in stalks,and the quality of the extracted RNA was compared.[Result] RNA extracted by kit extraction method had a high-yield,the bands were clear and RNA had a good integrity,there was no significant degradation of RNA,and the OD260 nm/OD280 nm value was closed to 2.0.[Conclusion] Kit extraction method was the effectively method to extract sugarcane RNA,and this study had provided a theoretical basis for the molecular biology study of sugarcane. 展开更多
关键词 SUGARCANE STALK RNA extraction method
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Effects of Dilute Acid-intensified Hydrolysis on Fermentative Biohydrogen Production Capacity of Maize Stalk 被引量:2
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作者 孙学习 李俊峰 +3 位作者 李涛 曾召刚 任保增 樊耀亭 《Agricultural Science & Technology》 CAS 2010年第8期1-3,共3页
[Objective] This study was to explore the effects of dilute acid hydrolysis on fermentative biohydrogen production capacity of maize stalk. [Method] Using maize stalks subjected to mechanical disintegration,steam expl... [Objective] This study was to explore the effects of dilute acid hydrolysis on fermentative biohydrogen production capacity of maize stalk. [Method] Using maize stalks subjected to mechanical disintegration,steam explosion and dilute acid hydrolysis as experimental materials,we measured and analyzed the effects of different treatments and particle size of maize stalk were analyzed. [Result] The optimal fermentative biohydrogen production was found under following parameters:pretreatment of 0.8% dilute H2SO4 following steam explosion,particle size of maize stalk of 0.425-0.850 mm,liquid-solid ratio [0.8% H2SO4 (M):stalk (W)] of 10:1. [Conclusion] Post steam explosion,dilute 0.8% dilute H2SO4 intensified hydrolysis on maize stalk could produce fermentative biohydrogen production capacity. 展开更多
关键词 Maize stalk Dilute acid-intensified hydrolysis Fermentative biohydrogen production
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Research upon the Structure and Pyrolysis of Cotton Stalk 被引量:1
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作者 冯雪 华坚 +2 位作者 毛炜坤 吴莉丽 尹华强 《Agricultural Science & Technology》 CAS 2011年第2期175-178,182,共5页
[Purpose]To research upon the structure and pyrolysis of cotton stalk.[Method] In this paper thermogravimetric analysis is adopted to study pyrolysis characteristics on the longitudinal direction of cotton stalk(the ... [Purpose]To research upon the structure and pyrolysis of cotton stalk.[Method] In this paper thermogravimetric analysis is adopted to study pyrolysis characteristics on the longitudinal direction of cotton stalk(the stick and the root)and on the traverse direction(the cuticle,cortex and medulla).[Result] Cotton stalk is a material of uneven and irregular texture,and there are great differences in the structure of all these parts on the longitudinal and traverse directions,especially in the contents of different components in each layer.The reaction in the stick and root becomes violent along with the increase in the rising rate of temperature,and carbon yield rate decreases in turn.Besides with the same rising rate of temperature,carbon yield rate of cotton stick is higher than the one of cotton root.Carbon yield rates of cuticle,cortex and medulla decrease in turn while the violence of the reaction in cuticle is less severe than in cortex and medulla.[Conclusion] It has provided theoretical basis for obtaining activated carbon technology of cotton stick. 展开更多
关键词 Cotton stalk Cotton root STRUCTURE PYROLYSIS
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Adsorption Performance of Activated Carbon Prepared from Corn Stalks
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作者 刘恩海 王长忠 +4 位作者 刘圣勇 潘嘉信 赵坤正 徐云婷 苏之勇 《Agricultural Science & Technology》 CAS 2016年第10期2221-2224,2231,共5页
[Objective] This study aimed to study the adsorption performance of activated carbon prepared from corn stalks. [Methed] With granular activated carbon prepared from corn stalks as research object, adsorption performa... [Objective] This study aimed to study the adsorption performance of activated carbon prepared from corn stalks. [Methed] With granular activated carbon prepared from corn stalks as research object, adsorption performance simulation test equipment was set up to investigate the adsorption performance of the prepared activated carbon for methanol by static weight method. In addition, the effects of adsorption bed structure, activated carbon particle size in adsorption bed, addition amount of graphite powder in activated carbon and modified activated carbon on systematic adsorption performance were studied. [Result] Under conditions of same activated carbon and same adsorption temperature, the adsorption performance of new adsorption bed A (installed with finned diaphragm adsorbate tubes) was signifi- cantly better than that of unmodified adsorption bed B. Compared with adsorption bed B, adsorption bed A took 5 min shorter to reach the adsorption amount of 0.22 g/g. Under the same adsorption temperature, the adsorption performance of bed loaded with different-particle size activated carbon was significantly better than that loaded with same-particle size activated carbon. The bed loaded with different-particle size activated carbon took 16 min shorter to reach the adsorption capacity of 0.22 g/g compared with the bed loaded with same-particle size activated carbon. Adding proper amount of graphite powder in activated carbon could enhance the thermal conductivity and strengthen the adsorption properties. The optimum addition amount of graphite powder was 20% of the total amount of activated carbon. Com- pared with that of the control, the adsorption performance of activated carbon soaked by weak acidic solution was significantly improved. It took 3 min shorter to reach 87.1% of the equilibrium adsorption amount. [Conclusion] This study will provide reference for optimizing structural design of adsorption bed and adsorption refrigeration system. 展开更多
关键词 Corn stalks Activated carbon Static weight method Adsorption performance
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Effects of Corn Stalk-composted Organic Fertilizer on Physiochemical Properties of Tobacco-growing Soil
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作者 刘洋 李爱华 《Agricultural Science & Technology》 CAS 2016年第11期2551-2554,共4页
In order to explore the method of returning corn stalk into field, the effects of returning corn stalk direcfly into soil and applying corn stalk-composted orgar^c fertilizer into soil on the physiochemical properties... In order to explore the method of returning corn stalk into field, the effects of returning corn stalk direcfly into soil and applying corn stalk-composted orgar^c fertilizer into soil on the physiochemical properties of tobacco-growing soil were studied. The results showed that returning corn stalk into soil could reduce soil bulk density and increase soil porosity, so as to improve the water and fertilizer retention capacity of tobacco-growing soil. At the same time, returning corn stalk into soil could also increase the organic matter, available phosphorus and available potassi- um contents in tobacco-growing soil. In the early field growth stage of tobacco, soil alkali-hydrolyzable nitrogen content decreased slightly; but in the middle and later field growth stage, the alkali-hydrolyzable nitrogen content in tobacco-growing soil increased. The treatment effect of corn stalk+urea+fermentation bacteria and corn stalk+urea+BM was better than that of the control (returning corn stalk directly into soil), indicating that the corn stalk-composted organic fertilizer had certain popular- ization value. 展开更多
关键词 Tobacco-growing soil Corn stalk Organic fertilizer Physiochemical properties NUTRIENT
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