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Optimizing hairy root production from explants of

Zhaogui YAN, Shengyu LIU, Junlian ZHANG, Guan HUANG, Lijun DUAN, Yaomei YE

《农业科学与工程前沿(英文)》 2020年 第7卷 第4期   页码 513-522 doi: 10.15302/J-FASE-2019272

摘要:

is a shrub that has been used in traditional herbal medicine. It has great pharmaceutical potential for treating diseases such as cancer and diabetes. As a prerequisite for propagation of this species on a large scale, hairy roots in were induced using and various factors affecting hairy root induction and growth evaluated. Seven factors were tested: (1) type of explant, (2) type of culture medium, (3) duration of pre-culture, (4) inoculum cell density, (5) duration of infection, (6) acetosyringone concentration in the culture medium, and (7) duration of incubation. The optimal protocol for hairy root induction and growth was: young shoots, pre-cultured in Y1 for 2 d, inoculated with broth with an OD of 0.6 for 20 min, and incubated for 3 d. Putative transgenic hairy roots were initially identified by morphology and then confirmed by polymerase chain reaction. Successful and optimal production of hairy roots is a critical prerequisite for industrial scale clonal propagation of . Being able to cultivate the plant on a large scale will provide rapid and ready supply of the plant materials that can be used in herbal medicine and in scientific and industrial exploitation.

关键词: hairy root induction     medicinal plant     MS growth medium     Phyllanthus hainanensis     Rhizobium rhizogenes    

Alternate partial root-zone irrigation with high irrigation frequency improves root growth and reduces

Shaoqing DU, Ling TONG, Shaozhong KANG, Fusheng LI, Taisheng DU, Sien LI, Risheng DING

《农业科学与工程前沿(英文)》 2018年 第5卷 第2期   页码 188-196 doi: 10.15302/J-FASE-2017176

摘要: Alternate partial root-zone irrigation (APRI) can improve water use efficiency in arid areas. However, the effectiveness and outcomes of different frequencies of APRI on water uptake capacity and physiological water use have not been reported. A two-year field experiment was conducted with two irrigation amounts (400 and 500 mm) and three irrigation methods (conventional irrigation, APRI with high and low frequencies). Root length density, stomatal conductance, photosynthetic rate, transpiration rate, leaf water use efficiency, midday stem and leaf water potentials were measured. The results show that in comparison with conventional irrigation, APRI with high frequency significantly increased root length density and decreased water potentials and stomatal conductance. No differences in the above indicators between the two APRI frequencies were detected. A significantly positive relationship between stomatal conductance and root length density was found under APRI. Overall, alternate partial root-zone irrigation with high frequency has a great potential to promote root growth, expand water uptake capacity and reduce unproductive water loss in the arid apple production area.

关键词: alternate partial root-zone irrigation     apple tree     leaf water use efficiency     root length density     stomatal conductance     water potential    

ROLE OF NITROGEN SENSING AND ITS INTEGRATIVE SIGNALING PATHWAYS IN SHAPING ROOT SYSTEM ARCHITECTURE

《农业科学与工程前沿(英文)》 2022年 第9卷 第3期   页码 316-332 doi: 10.15302/J-FASE-2022441

摘要:

● The Green Revolution broadened the trade-off between yield and nitrogen-use efficiency.

关键词: Nitrogen     root system architecture     phytohormone     crosstalk     nitrogen-use efficiency     breeding strategy    

The evolution of surgical and medical treatment of aortic root aneurysm

null

《医学前沿(英文)》 2014年 第8卷 第4期   页码 427-432 doi: 10.1007/s11684-014-0385-4

摘要:

Since first report of aortic root replacement in 1968, the surgical risk and long term outcome of patients with aortic root aneurysm have been continuously improving. In the last 30 years, the surgical approach is also evolving towards more valve conservation with prophylactical intervention at an earlier clinical stage. Translational research has also led to emerging surgical innovation and new drug therapy. Their efficacies are currently under vigorous clinical trials and evaluations.

关键词: aortic root aneurysm     aortic root replacement     valve sparing root replacement     personalised external aortic root support    

Effects of previous drying of sediment on root functional traits and rhizoperformance of emerged macrophytes

《环境科学与工程前沿(英文)》 2021年 第15卷 第6期 doi: 10.1007/s11783-021-1427-1

摘要:

• Sediment desiccation alters morphological characteristics of aquatic sediment.

关键词: Fibrous-root macrophytes     Thick-root macrophytes     Nutrients removal     Wet sediment     Dried-rewetted sediment    

Improving the efficiency and effectiveness of global phosphorus use: focus on root and rhizosphere levels

null

《农业科学与工程前沿(英文)》 2019年 第6卷 第4期   页码 357-365 doi: 10.15302/J-FASE-2019275

摘要:

Phosphorus (P) is essential for life and for efficient crop production, but global P use with limited recycling is inefficient in several sectors, including agronomy. Unfortunately, plant physiologists, agronomists, farmers and end users employ different measures for P use efficiency (PUE), which often masks their values at different scales. The term P use effectiveness, which also considers energetic and sustainability measures in addition to P balances, is also a valuable concept. Major physiological and genetic factors for plant P uptake and utilization have been identified, but there has been limited success in genetically improving PUE of modern crop cultivars. In maize, studies on root architectural and morphological traits appear promising. Rhizosphere processes assist in mobilizing and capturing sparingly soluble phosphate from rock phosphate. Combinations of phosphate-solubilizing microorganisms with ammonium-based nitrogen fertilizer, as well as strategies of fertilizer placement near the roots of target crops, can moderately enhance PUE. The desired concentration of P in the products differs, depending on the final use of the crop products as feed, food or for energy conversion, which should be considered during crop production.

关键词: acquisition efficiency     plant growth promoting rhizobacteria     phosphate     use efficiency     utilization efficiency    

A knowledge reasoning Fuzzy-Bayesian network for root cause analysis of abnormal aluminum electrolysis

Weichao Yue, Xiaofang Chen, Weihua Gui, Yongfang Xie, Hongliang Zhang

《化学科学与工程前沿(英文)》 2017年 第11卷 第3期   页码 414-428 doi: 10.1007/s11705-017-1663-x

摘要: Root cause analysis (RCA) of abnormal aluminum electrolysis cell condition has long been a challenging industrial issue due to its inherent complexity in analyzing based on multi-source knowledge. In addition, accurate RCA of abnormal aluminum electrolysis cell condition is the precondition of improving current efficiency. RCA of abnormal condition is a complex work of multi-source knowledge fusion, which is difficult to ensure the RCA accuracy of abnormal cell condition because of dwindling and frequent flow of experienced technicians. In view of this, a method based on Fuzzy-Bayesian network to construct multi-source knowledge solidification reasoning model is proposed. The method can effectively fuse and solidify the knowledge, which is used to analyze the cause of abnormal condition by technicians providing a clear and intuitive framework to this complex task, and also achieve the result of root cause automatically. The proposed method was verified under 20 sets of abnormal cell conditions, and implements root cause analysis by finding the abnormal state of root node, which has a maximum posterior probability by Bayesian diagnosis reasoning. The accuracy of the test results is up to 95%, which shows that the knowledge reasoning feasibility for RCA of aluminum electrolysis cell.

关键词: abnormal aluminum electrolysis cell condition     Fuzzy-Bayesian network     multi-source knowledge solidification and reasoning     root cause analysis    

Constant temperature control of tundish induction heating power supply for metallurgical manufacturing

Yufei YUE, Qianming XU, Peng GUO, An LUO

《能源前沿(英文)》 2019年 第13卷 第1期   页码 16-26 doi: 10.1007/s11708-018-0572-0

摘要: The tundish induction heating power supply (TIHPS) is one of the most important equipment in the continuous casting process for metallurgical manufacturing. Specially, the constant temperature control is greatly significant for metallurgical manufacturing. In terms of the relationship between TIH load temperature and output power of TIHPS, the constant temperature control can be realized by power control. In this paper, a TIHPS structure with three-phase PWM rectifiers and full-bridge cascaded inverter is proposed. Besides, an input harmonic current blocking strategy and a load voltage feedforward control are also proposed to realize constant temperature control. To meet the requirement of the system, controller parameters are designed properly. Experiments are conducted to validate the feasibility and effectiveness of the proposed TIHPS topology and the control methods.

关键词: tundish induction heating power supply (TIHPS)     constant temperature control     input harmonic current blocking     load voltage feedforward    

Brown and beige fat: the metabolic function, induction, and therapeutic potential

null

《医学前沿(英文)》 2015年 第9卷 第2期   页码 162-172 doi: 10.1007/s11684-015-0382-2

摘要:

Adipose tissue is an important organ for energy homeostasis. White adipose tissue stores energy in the form of triglycerides, whereas brown adipocytes and recently identified beige adipocytes are specialized in dissipating energy by thermogenesis or contribution to dispose glucose and clear triglycerides in blood. The inverse correlation between the brown adipose tissue activity and body mass suggests its protective role against body fat accumulation. Thus, recruitment and activation of brown or beige adipose tissue become particularly appealing targets for increasing energy expenditure. Angiogenesis and sympathetic nerve signals are the fundamental determinants for brown and beige adipose tissue development, as well as for their metabolic functions. Secretary factors including BMPs can induce the development, the activation of brown or beige adipose tissue, which seem to be promising for therapeutic development.

关键词: brown adipocyte     beige adipocyte     metabolism     obesity    

Estimation of composite load model with aggregate induction motor dynamic load for an isolated hybrid

Nitin Kumar SAXENA,Ashwani Kumar SHARMA

《能源前沿(英文)》 2015年 第9卷 第4期   页码 472-485 doi: 10.1007/s11708-015-0373-7

摘要: It is well recognized that the voltage stability of a power system is affected by the load model and hence, to effectively analyze the reactive power compensation of an isolated hybrid wind-diesel based power system, the loads need to be considered along with the generators in a transient analysis. This paper gives a detailed mathematical modeling to compute the reactive power response with small voltage perturbation for composite load. The composite load is a combination of the static and dynamic load model. To develop this composite load model, the exponential load is used as a static load model and induction motors (IMs) are used as a dynamic load model. To analyze the dynamics of IM load, the fifth, third and first order model of IM are formulated and compared using differential equations solver in Matlab coding. Since the decentralized areas have many small consumers which may consist large numbers of IMs of small rating, it is not realistic to model either a single large rating unit or all small rating IMs together that are placed in the system. In place of using a single large rating IM, a group of motors are considered and then the aggregate model of IM is developed using the law of energy conservation. This aggregate model is used as a dynamic load model. For different simulation studies, especially in the area of voltage stability with reactive power compensation of an isolated hybrid power system, the transfer function of the composite load is required. The transfer function of the composite load is derived in this paper by successive derivation for the exponential model of static load and for the fifth and third order IM dynamic load model using state space model.

关键词: isolated hybrid power system (IHPS)     composite load model     static load     dynamic load     induction motor load model     aggregate load    

Experimental investigation and comparative study of inter-turn short-circuits and unbalanced voltage supply in induction

Fatima BABAA, Abdelmalek KHEZZAR, Mohamed el kamel OUMAAMAR

《能源前沿(英文)》 2013年 第7卷 第3期   页码 271-278 doi: 10.1007/s11708-013-0258-6

摘要: A transient model for an induction machine with stator winding turn faults on a single phase is derived using reference frame transformation theory. The negative sequence component and the 3rd harmonic are often considered as accurate indicators. However, small unbalance in the supply voltage and/or in the machine structure that exists in any real system engenders the same harmonics components. In this case, it is too difficult to distinguish between the current harmonics due to the supply voltage and those originated by inter-turn short-circuit faults. For that, to have the correct diagnosis and to increase the sensitivity and the reliability of the diagnostic system, it is crucial to provide the relationship between the inter-turn short-circuits in the stator winding and the supply voltage imbalance through an accurate mathematical model and via a series of experimental essays.

关键词: induction machines     fault indicator     inter-turn short-circuit fault     unbalance supply voltage    

A new and best approach for early detection of rotor and stator faults in induction motors coupled to

Abderrahim ALLAL,Boukhemis CHETATE

《能源前沿(英文)》 2016年 第10卷 第2期   页码 176-191 doi: 10.1007/s11708-015-0386-2

摘要: Today, induction machines are playing, thanks to their robustness, an important role in world industries. Although they are quite reliable, they have become the target of various types of defects. Thus, for a long time, many research laboratories have been focusing their works on the theme of diagnosis in order to find the most efficient technique to predict a fault in an early stage and to avoid an unplanned stopping in the chain of production and costs ensuing. In this paper, an approach called Park’s vector product approach (PVPA) was proposed which was endowed with a dominant sensitivity in the case in which there would be rotor or stator faults. To show its high sensitivity, it was compared with the classical methods such as motor current signature analysis (MCSA) and techniques studied in recent publications such as motor square current signature analysis (MSCSA), Park’s vector square modulus (PVSM) and Park-Hilbert (P-H) (PVSM ). The proposed technique was based on three main steps. First, the three-phase currents of the induction motor led to a Park’s vector. Secondly, the proposed PVPA was calculated to show the distinguishing spectral signatures of each default and specific frequencies. Finally, simulation and experimental results were presented to confirm the theoretical assumptions.

关键词: induction motor     incipient broken bar     extended Park’s vector approach     spectral analysis     inter-turn short-circuit     Hilbert transform    

Reduced texaphyrin: A ratiometric optical sensor for heavy metals in aqueous solution

Root, Gregory Thiabaud, Jonathan L. Sessler

《化学科学与工程前沿(英文)》 2020年 第14卷 第1期   页码 19-27 doi: 10.1007/s11705-019-1888-y

摘要: We report here a water-soluble metal cation sensor system based on the as-prepared or reduced form of an expanded porphyrin, texaphyrin. Upon metal complexation, a change in the redox state of the ligand occurs that is accompanied by a color change from red to green. Although long employed for synthesis in organic media, we have now found that this complexation-driven redox behavior may be used to achieve the naked eye detectable colorimetric sensing of several number of less-common metal ions in aqueous media. Exposure to In(III), Hg(II), Cd(II), Mn(II), Bi(III), Co(II), and Pb(II) cations leads to a colorimetric response within 10 min. This process is selective for Hg(II) under conditions of competitive analysis. Furthermore, among the subset of response-producing cations, In(III) proved unique in giving rise to a ratiometric change in the ligand-based fluorescence features, including an overall increase in intensity. The cation selectivity observed in aqueous media stands in contrast to what is seen in organic solvents, where a wide range of texaphyrin metal complexes may be prepared. The formation of metal cation complexes under the present aqueous conditions was confirmed by reversed phase high-performance liquid chromatography, ultra-violet-visible absorption and fluorescence spectroscopies, and high-resolution mass spectrometry.

关键词: texaphyrin     fluorescent sensor     ion-sensing     indium     mercury    

The Major Root Causes of Smog in China and Technologies and Solutions to Reduce It

Ke Liu

《工程管理前沿(英文)》 2016年 第3卷 第4期   页码 343-348 doi: 10.15302/J-FEM-2016053

摘要: This paper discusses the two major root causes of smog in China. The first one is the distributed coal combustion in many small and medium sized boilers which have no emission control systems installed. To resolve this problem, there are several ways, such as increasing the centralized coal combustion for heat and power cogeneration; or converting coal to SNG in areas where there is enough water resource and removing the pollutants of the coal in the centralized coal to SNG plant, or refining the coal and making it cleaner first before combustion. The second major cause of smog is the low quality diesel and outdated diesel engines used in China. To solve this problem, there are some ways, such as improving the diesel quality to meet the national V standard, and meanwhile, enhancing the law enforcement to eliminate these outdated diesel engines that do not meet the national emission standards; in addition, combusting cleaner and cheaper fuel such as methanol or DME in the diesel engines is also an option for certain areas where there are abundant alternative fuels such as methanol to replace diesel.

关键词: smog     emissions     coal refining     coal utilization     solutions    

Multiple target implementation for a doubly fed induction generator based on direct power control under

Heng NIAN,Yi-peng SONG

《信息与电子工程前沿(英文)》 2015年 第16卷 第4期   页码 321-334 doi: 10.1631/FITEE.1400170

摘要: This paper presents a multiple target implementation technique for a doubly fed induction generator (DFIG) under unbalanced and distorted grid voltage based on direct power control (DPC). Based on the mathematical model of DFIG under unbalanced and distorted voltage, the proportional and integral (PI) regulator is adopted to regulate the DFIG average active and reactive powers, while the vector PI (VPI) resonant regulator is used to achieve three alternative control targets: (1) balanced and sinusoidal stator current; (2) smooth instantaneous stator active and reactive powers; (3) smooth electromagnetic torque and instantaneous stator reactive power. The major advantage of the proposed control strategy over the conventional method is that neither negative and harmonic sequence decomposition of grid voltage nor complicated control reference calculation is required. The insensitivity of the proposed control strategy to DFIG parameter deviation is analyzed. Finally, the DFIG experimental system is developed to validate the availability of the proposed DPC strategy under unbalanced and distorted grid voltage.

关键词: Direct power control     Doubly fed induction generator     Unbalanced and distorted grid voltage     Vector proportional and integral resonant regulator     Parameter deviation    

标题 作者 时间 类型 操作

Optimizing hairy root production from explants of

Zhaogui YAN, Shengyu LIU, Junlian ZHANG, Guan HUANG, Lijun DUAN, Yaomei YE

期刊论文

Alternate partial root-zone irrigation with high irrigation frequency improves root growth and reduces

Shaoqing DU, Ling TONG, Shaozhong KANG, Fusheng LI, Taisheng DU, Sien LI, Risheng DING

期刊论文

ROLE OF NITROGEN SENSING AND ITS INTEGRATIVE SIGNALING PATHWAYS IN SHAPING ROOT SYSTEM ARCHITECTURE

期刊论文

The evolution of surgical and medical treatment of aortic root aneurysm

null

期刊论文

Effects of previous drying of sediment on root functional traits and rhizoperformance of emerged macrophytes

期刊论文

Improving the efficiency and effectiveness of global phosphorus use: focus on root and rhizosphere levels

null

期刊论文

A knowledge reasoning Fuzzy-Bayesian network for root cause analysis of abnormal aluminum electrolysis

Weichao Yue, Xiaofang Chen, Weihua Gui, Yongfang Xie, Hongliang Zhang

期刊论文

Constant temperature control of tundish induction heating power supply for metallurgical manufacturing

Yufei YUE, Qianming XU, Peng GUO, An LUO

期刊论文

Brown and beige fat: the metabolic function, induction, and therapeutic potential

null

期刊论文

Estimation of composite load model with aggregate induction motor dynamic load for an isolated hybrid

Nitin Kumar SAXENA,Ashwani Kumar SHARMA

期刊论文

Experimental investigation and comparative study of inter-turn short-circuits and unbalanced voltage supply in induction

Fatima BABAA, Abdelmalek KHEZZAR, Mohamed el kamel OUMAAMAR

期刊论文

A new and best approach for early detection of rotor and stator faults in induction motors coupled to

Abderrahim ALLAL,Boukhemis CHETATE

期刊论文

Reduced texaphyrin: A ratiometric optical sensor for heavy metals in aqueous solution

Root, Gregory Thiabaud, Jonathan L. Sessler

期刊论文

The Major Root Causes of Smog in China and Technologies and Solutions to Reduce It

Ke Liu

期刊论文

Multiple target implementation for a doubly fed induction generator based on direct power control under

Heng NIAN,Yi-peng SONG

期刊论文