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A precise phase modulation and demodulation method was proposed to retrieve temperature distributions in axisymmetric flames by using a single-wavelength large lateral shearing interferometer. A spatial light modulator (SLM) was employed to vary the phases in each pixel continuously in the flame-phase measurement. The uniqueness of the phase extraction was mathematically proved for the first time, and a least square method was applied to recover the profile of flame phase in the interferometer. The ambiguity of the phases at different cycles of $2\pi $ was eliminated. The phase shift at each pixel was uniquely determined and verified by using simulated data. Further, precise-phase distributions were utilized to retrieve the temperature distribution in a laminar flame. In actual experiments, four axisymmetric laminar flames from diffused to premixed flames were generated by using a Bunsen burner. Profiles of temperature distribution in the flames were extracted and agreed well with the results scanned by using a thermocouple. With the increase of airflow rate, the position of high-temperature zone was observed moving down, and the thermal structure of the premixed flame became more and more obvious. The preheating zone, reaction front, and reaction zone inside the flames were clearly captured.

Plant survival in the terrestrial ecosystem is influenced by both beneficial and harmful microbes. Trichoderma spp. are a group of filamentous fungi that promote plant growth and resistance to harmful microbes. Previously, we showed that the genus Trichoderma could effectively suppress Fusarium wilt in cucumber. However, the mechanisms that underlie the effects of the genus Trichoderma on plant defense have not been fully substantiated. Two essential metabolic pathways, such as the ascorbate (AsA)-glutathione (GSH) cycle and the oxidative pentose phosphate pathway (OPPP), have been shown to participate in plant tolerance to biotic stressors; nevertheless, the involvement of these pathways in Trichoderma-induced enhanced defense remains elusive. Here, we show that Trichoderma harzianum could alleviate oxidative and nitrostative stress by minimizing reactive oxygen species (ROS; hydrogen peroxide and superoxide) and reactive nitrogen species (nitric oxide [NO]) accumulation, respectively, under Fusarium oxysporum infection in cucumber roots. The genus Trichoderma enhanced antioxidant potential to counterbalance the overproduced ROS and attenuated the transcript and activity of NO synthase and nitrate reductase. The genus Trichoderma also stimulated S-nitrosylated glutathione reductase activity and reduced S-nitrosothiol and S-nitrosylated glutathione content. Furthermore, the genus Trichoderma enhanced AsA and GSH concentrations and activated their biosynthetic enzymes, γ-GCS and l-galactono-1,4-lactone dehydrogenase. Interestingly, the genus Trichoderma alleviated Fusarium-inhibited activity of glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase, enzymes involved in the OPPP. Such positive regulation of the key enzymes indicates the adequate maintenance of the AsA-GSH pathway and the OPPP, which potentially contributed to improve redox balance, energy flow, and defense response. Our study advances the current knowledge of Trichoderma-induced enhanced defense against F. oxysporum in cucumber.

It is difficult to extract a narrow road with a width of only a few pixels from a remote sensing image. In order to solve this problem, it is proposed to process the remote sensing image with super-resolution. This paper extends the details of narrow roads by using the Deep Convolutional Neural Network (DCNN) method. Next, some noise points or roads of error extraction are processed by topological structure. To verify performance of the experimental method, experimental research on open remote sensing image data set is carried out. The experimental result is to compare the original image, super-resolution image, and topology filtering. Experimental results demonstrate that the new method has better effectiveness and superiority over the original remote sensing image.

For the problem of image matching in visual indoor positioning research, the image quality is degraded due to the interference and influence of noises during the generation or transmission of the image, which ultimately leads to the problem of image matching rate and low efficiency. Comparing existing traditional denoising algorithms and wavelet transform algorithms, we use MATLAB for simulation to compare the effects of adding different noises and denoising with different wavelet bases. The results show that the wavelet image denoising improves the shortcomings of the traditional denoising algorithm to a certain extent, but there is still room for improvement.

Introduction: The transmission pathways of coronavirus disease 2019 (COVID-19) remain not completely clear. In this case study the test for the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in pharyngeal swab and anal swab were compared. Case presentation: A 3-month-old girl was admitted to our hospital with COVID-19. Her parents had both been diagnosed with COVID-19. The results of pharyngeal swab and anal swab of the little girl were recorded and compared during the course of the disease. The oropharyngeal specimen showed negative result for SARS-CoV-2 on the 14th day after onset of the illness. However, the anal swab was still positive for SARS-CoV-2 on the 28th day after the onset of the illness. Conclusion: The possibility of fecal-oral transmission of COVID-19 should be assessed. Personal hygiene during home quarantine merits considerable attention. Key words: COVID-19; Anal swab; SARS-CoV-2; Fecal-oral transmission

Histone deacetylase 4 (HDAC4) is involved in the development of multiple types of cancers. In this study, we aimed to investigate the expression and clinical significance of HDAC4 in hepatocellular carcinoma (HCC).49 patients with stage B HCC who underwent surgical resection were enrolled in this study. All patients were followed up with an observation time of 4.8 to 7 years. Immunohistochemistry was applied to investigate the expression level of HDAC4.HDAC4 protein is over-expressed in HCC tissues compared with matched adjacent non-cancer tissues. Kaplan-Meier analysis shows that the positive expression of HDAC4 is associated with poor survival in these patients.Our study shows that HDAC4 over-expression is important for the development of advanced HCC, which may serve as a useful prognostic biomarker and therapeutic target for this malignancy.

The impact abrasive wear behaviors of light-weight austenitic Fe-24Mn-7Al-lC steel with increasing impact wear conditions were studied by comparing with the modified Hadfield (Mnl3Cr2) steel. Wear tests were performed with the MLD-10 abrasive wear testing machine. Main parameters such as impact energy, impacting frequency and wear time were evaluated. To explore the abrasive wear behaviors under different impact energies, the parameters including mass loss, wear resistance and hardness were evaluated in detail. The microstructures of the steels were further analyzed using optical microscopy (OM), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD). Results showed that the light-weight austenitic Fe-24Mn-7Al-lC steel had a better wear resistance than Mnl3Cr2 steel under the impact energy tested. The wear resistance of light-weight austenitic Fe-24Mn-7Al-lC steel was about 1. 09 – 1. 17 times as high as that of Mnl3Cr2 steel under low and medium impact energy (0. 5 – 2. 0 J) conditions, and 1. 41 times under high impact energy (4. 0 J) condition. In Mnl3Cr2 steel, the evolution of dislocation substructure with increasing impact energy showed typical stacking fault, interaction of twins and dislocations, as well as mechanical twins. The high work-hardening rate in Fe-24Mn-7Al-lC steel was caused by Taylor lattice and high density of dislocation tangles.

Fusarium wilt, one of the destructive diseases of cucumber can be effectively controlled by using biocontrol agents such as Trichoderma harzianum. However, the mechanisms controlling T. harzianum-induced enhanced resistance remain largely unknown in cucumber plants. Here we screened the potent T. harzianum isolate TH58 that could effectively control F. oxysporum (FO). Glasshouse efficacy trials also showed that TH58 decreased disease incidence by 69.7 %. FO induced ROS over accumulation, while TH58 inoculation suppressed ROS over accumulation and improved root cell viability under F. oxysporum infection. TH58 inoculation could reverse the FO-induced cell division block and regulate the proportional distribution of nuclear DNA content through inducing 2C fraction. Moreover, the expression levels of cell cycle-related genes such as CDKA, CDKB, CycA, CycB, CycD3;1 and CycD3;2 in TH58 - pre-inoculated seedlings were up-regulated compared with those infected with FO alone. Taken together, these results suggest that T. harzianum improved plant resistance against Fusarium wilt disease via alterations in nuclear DNA content and cell cycle-related genes expression that might maintain a lower ROS accumulation and higher root cell viability in cucumber seedlings.

Intestinal lipomas are rare nonepithelial tumors that are typically small in size and detected incidentally. Colonic intussusception is an uncommon complication of colonic lipoma. A 56 y old woman visited our emergency room with sudden onset of intermittent abdominal cramps. A CT scan showed a 5.0 cm, nodular, homogenous, hypodense structure in the hepatic flexure of the colon as the lead point of an intussusception. The hypodense structure was suggestive of a colonic lipoma, and the tumor was suspected to be the cause of the intestinal intussusception. Laparoscopic exploration was performed, and the pathology demonstrated a mature submucosal colonic lipoma. In addition to the case report, we discuss the role of imaging modalities in diagnosing neoplasms and for assessing the clinical behavior of lipomas when symptomatic.

Mycorrhizal inoculation stimulates growth, photosynthesis and nutrient uptake in a wide range of host plants. However, the ultimate effects of arbuscular mycorrhyzal (AM) symbiosis vary with the plants and fungal species involved in the association. Therefore, identification of the appropriate combinations of AM fungi (AMF) that interact synergistically to improve their benefits is of high significance. Here, three AM fungal compositions namely VT (Claroideoglomus sp., Funneliformis sp., Diversispora sp., Glomus sp., and Rhizophagus sp.) and BF (Glomus intraradices, G. microageregatum BEG and G. Claroideum BEG 210), and Funneliformis mosseae (Fm) were investigated with respect to the growth, gas exchange parameters, enzymes activities in Calvin cycles and related gene expression in cucumber seedlings. The results showed that VT, BF and Fm could successfully colonize cucumber root to a different degree with the colonization rates 82.38, 74.65, and 70.32% at 46 days post inoculation, respectively. The plant height, stem diameter, dry weight, root to shoot ratio of cucumber seedlings inoculated with AMF increased significantly compared with the non-inoculated control. Moreover, AMF colonization greatly increased the root activity, chlorophyll content, net photosynthetic rate, light saturated rate of the CO2 assimilation (Asat), maximum carboxylation rate (Vcmax) and maximum ribulose-1,5-bis-phosphate (RuBP) regeneration rate (Jmax), which were increased by 52.81, 30.75, 58.76, 47.00, 69.15, and 65.53% when inoculated with VT, respectively. The activities of some key enzymes such RuBP carboxylase/oxygenase (RuBisCO), D-fructose-1,6-bisphosphatase (FBPase), D-fructose-6-phosphatase (F6P) and ribulose-5-phosphate kinase (Ru5PK), and related gene expression involved in the Calvin cycle including RCA, FBPase, FBPA, SBPase, rbcS and rbcL were upregulated by AMF colonization. AMF inoculation also improved macro- and micro nutrient contents such as N, P, K, S, Ca, Cu, Fe, Mn, Mg, and Zn in roots. Further analysis revealed that inoculation with VT had relatively better effect on growth of cucumber seedling followed by BF and Fm, indicating that AMF composition consisting of distant AMF species may have a better effect than a single or closely related AMF spp. This study advances the understanding of plant responses to different AM fungi toward development of strategies on AMF-promoted vegetable production.

Ubiquitination is a common regulatory mechanism, playing a critical role in diverse cellular and developmental processes in eukaryotes. However, a few reports on the functional correlation between E3 ubiquitin ligases and reactive oxygen species (ROS) or reactive nitrogen species (RNS) metabolism in response to stress are currently available in plants. In the present study, the E3 ubiquitin ligase gene AdBiL (Adi3 Binding E3 Ligase) was introduced into tomato line Ailsa Craig via Agrobacterium-mediated method. Transgenic lines were confirmed for integration into the tomato genome using PCR. Transcription of AdBiL in various transgenic lines was determined using real-time PCR. Evaluation of stress tolerance showed that T1 generation of transgenic tomato lines showed only mild symptoms of chilling injury as evident by higher biomass accumulation and chlorophyll content than those of non-transformed plants. Compared with wild-type plants, the contents of AsA, AsA/DHA, GSH and the activity of GaILDH, γ-GCS and GSNOR were increased, while H2O2, O2•–, MDA, NO, SNOs and GSNO accumulations were significantly decreased in AdBiL overexpressing plants in response to chilling stress. Furthermore, transgenic tomato plants overexpressing AdBiL showed higher activities of enzymes such as G6PDH, 6PGDH, NADP-ICDH and NADP-ME involved in Pentose Phosphate Pathway. The transgenic tomato plants also exhibited an enhanced tolerance against the necrotrophic fungus Cladosporium fulvum. Tyrosine nitration protein was activated in the plants infected with leaf mold disease, while the inhibition could be recovered in AdBiL gene overexpressing lines. Taken together, our results revealed a possible physiological role of AdBiL in the activation of the key enzymes of AsA-GSH cycle, pentose phosphate pathway and down-regulation of GSNO reductase, thereby reducing oxidative and nitrosative stress in plants. This study demonstrates an optimized transgenic strategy using AdBiL gene for crop improvement against biotic and abiotic stress factors.

This paper presents an evaluation study of the navigation effectiveness of a multifaceted organizational taxonomy that was built on the Dewey Decimal Classification and several domain thesauri in the area of library and information science education. The objective of the evaluation was to detect deficiencies in the taxonomy and to infer problems of applied construction steps from users' navigation difficulties. The evaluation approach included scenario-based navigation exercises and postexercise interviews. Navigation exercise errors and underlying reasons were analyzed in relation to specific components of the taxonomy and applied construction steps. Guidelines for the construction of the hierarchical structure and categories of an organizational taxonomy using existing general classification schemes and domain thesauri were derived from the evaluation results.

The CCT (continuous cooling transformation) curve of the test steel was obtained on Gleeble-1500 thermal mechanical simulator based on the thermal dilation measurement. The test steels were the deformation with 40% under the temperature of 900°C and then were cooled to room temperature at different cooling rates. The phase transformation law and hardness change rule were emphatically investigated at the cooling rate from 0.05°C/s to 30°C/s by optical microscopy (OM), scanning electron microscope (SEM) and Vickers hardness tester. The regression model of phase transformation was calculated. The results show that the transformation of ferrite and pearlite are inhibited, which cause the dynamic CCT curve shift to the right. The microstructure of the test steel consists of ferrite and pearlite after phase transformation at the cooling rate of 0.05°C/s; the granular bainite appears at the cooling rate of 0.5°C/s due to the interaction of Mo and B; as the cooling rate increases to 2°C/s, the microstructure mainly consists of lath bainite; the martensite is observed at the cooling rate of 2°C/s and there would be total martensite if the cooling rate is higher than 5°C/s and the grain growth rate is faster at the same time. The hardness of test steels increases with the increase of cooling rate, and increases obviously when the cooling rate is lower than 5 °C/s. A theoretical basis is provided to obtain the best bainite/martensite composite microstructure. The martensitic transformation start temperature is 354.6°C and the critical cooling rate is 5°C/s. The test value and the regression model can fit well and reflect the test value trend, showing a high precision of regression.

The universal symbiotic associations between arbuscular mycorrhizal fungi (AMF) and plant roots remarkably stimulate plant growth, nutrient uptake, and stress responses. The present study investigated the stress ameliorative potential of the AM fungus Funneliformis mosseae against chilling in tomato seedlings. AMF-inoculated tomato seedlings exhibited significantly higher fresh weight and dry weight than non-AMF control plants under both control (25/15 °C) and low temperature (8 °C/4 °C) treatments. Under chilling stress, AMF inoculation significantly reduced the level of MDA, H2O2, and O 2 ·− along with increased calcium precipitates in the apoplast and vacuole of root cells compared with the non-AMF control. Furthermore, AMF inoculation induced activities of antioxidant enzymes and transcripts of related genes under chilling stress. Notably, AMF inoculation resulted in reduced redox state in root cells as evident by significantly increased content of reduced ascorbate, reduced glutathione, redox ratio, and the activity of l-galactono-1,4-lactone dehydrogenase in the tomato roots both under control and low temperature. Taken together, these results indicate that AMF could play an important role in optimizing chilling resistance by maintaining redox poise and calcium balance in tomato seedlings.

The flow stress, microstructure and softening mechanism of NM550 wear-resistant steel were investigated via hot compression test by using Gleeble-1500 thermal simulator in a temperature range from 800 to 1150 °C and strain rate range from 0.1 to 10s−1. With optical microscopy (OM), the effects of temperature, strain rate and true strain on the flow behavior and microstructure of the steel were discussed. The results show that the dynamic recrystallization occurs at higher temperature and lower strain rate. Hot deformation behavior of the steel specimens is sensitive to temperature and strain rate, while the strain rate affects the hot deformation behavior greatly. The apparent stress exponent and the apparent activation energy of the specimens are 7.395 and 389.611 kJ/mol, respectively. With the experimental data, the hot deformation constitutive equation and processing map of the NM550 wear-resistant steel are given. Finally, a combination of the constitutive equation and processing map provides a method for comprehensively investigating the hot deformation behavior of the steel under different conditions, and provides theoretical basis for the determination of rolling procedure in industrial production.

PurposeThe purpose of this paper is to examine the recent recession in the USA and its impact on libraries. It illustrates how libraries are coping with the fiscal constraints and challenges this economic climate imposes. It seeks to provide timely feedback and best practices from librarians and administrators (mostly academic) regarding measures they are taking and their plans for the future.Design/methodology/approachThe literature review reveals news regarding library budget cuts and their impact on collections, operations, and personnel. Two online surveys were conducted, one of the library community at large, the other of the Association of Research Libraries (ARL) deans and directors.FindingsA majority of the libraries have experienced flat or reduced budgets and many expect additional budget cuts in the immediate future. Key areas affected include collections/materials, professional development/travel, supplies/equipment, personnel and hours of operation. Survey respondents suggest that library administrators and librarians should examine workflow to increase efficiency, prioritize projects, and adopt creative measures.Practical implicationsThis article provides informative and practical suggestions for those managing budgets in difficult economic times.Originality/valueData collected provide a snapshot of the financial constraints libraries currently face. It provides practical lessons and suggestions for library administrators and librarians seeking to cope with flat or reduced budgets while maintaining quality services.

Employee recruitment and retention are keys to the overall success of academic libraries, library administrators, and search committees face challenges when filling new and vacant faculty positions. This article presents and discusses the findings of a survey on hiring in an academic setting, including subjects such as staffing, criteria for hiring, how search committees evaluate candidates, and length of the hiring process. This research study reveals answers from 242 survey respondents who shared their experiences and opinions regarding the hiring process in academic libraries. The aim of this study to unlock the mystery involving faculty searches by examining key factors affecting the odds of obtaining an interview and the outcome of an application. The findings help people on both sides of the job search equation form a better understanding of the hiring process. This information should be taken into consideration by those applying for a position to learn how to best present themselves and by search c...

PurposeThis paper seeks to examine attitudes toward the use of clickers, as well as practicalities and pedagogical considerations that inform them. Drawing on interviews from a variety of viewpoints at one institution of higher education, this paper aims to situate a librarian perspective among those of teaching faculty, administration, and students.Design/methodology/approachThis paper is a case study of a single institution of higher education in which the experiences of teaching faculty, an administrator, and a library faculty member are gathered using semi‐structured interviews. Student opinions are obtained through the use of a focus‐group interview.FindingsThis paper provides attitudes and experiences of nursing teaching faculty who use clickers in their instruction, an administrator who purchased clickers for his department, and a library faculty member who uses clickers in bibliographic instruction, as well as those of nursing students who used the technology in class.Research limitations/implicationsBecause of the nature of the research method employed, reported results may not be universally generalizable.Practical implicationsThis paper may help inform the choices of those deciding to use clickers in their instruction.Originality/valueThis paper fulfills an identified need to analyze reactions to clicker use in instruction among students, instructors, and other program participants, including librarians.

An online survey was sent to academic libraries and consortia with an integrated library system (ILS) migration project, based on review of press releases from major U.S. ILS vendors. This study takes a systematic approach to provide a snapshot of the academic ILS market and key factors affecting the outcome of an ILS migration project. It reveals the challenges and opportunities facing academic libraries and ILS vendors in an environment with rapidly changing technology and increasingly sophisticated academic users.

As institutions of higher learning focus on positioning strategically in the global and online education market, it is critical for academic libraries to realize their roles in supporting the institutional missions, one of which is to assist scholars, faculty, and students, regardless of location. This responsibility is fulfilled not only through the talents and dedication of librarians and library staff, but also with technology. The Brooklyn Campus Library of Long Island University (LIU) seized the opportunity and took a proactive approach to providing library resources and services to the university's Global College (GC) community. After carefully evaluating the needs of faculty and students across the globe, the authors recount how the library supports the teaching and learning activities of this unique user group. A library portal enables users at various international sites to use the library's abundant resources and customized services with ease, as well as to ensure that the library serves the Glo...

PurposePotential and benefits of classification schemes and thesauri in building organizational taxonomies cannot be fully utilized by organizations. Empirical data of building an organizational taxonomy by the top‐down approach of using classification schemes and thesauri appear to be lacking. The paper seeks to make a contribution in this regard.Design/methodology/approachA case study of building an organizational taxonomy was conducted in the information studies domain for the Division of Information Studies at Nanyang Technology University, Singapore. The taxonomy was built by using the Dewey Decimal Classification, the Information Science Taxonomy, two information systems taxonomies, and three thesauri (ASIS&T, LISA, and ERIC).FindingsClassification schemes and thesauri were found to be helpful in creating the structure and categories related to the subject facet of the taxonomy, but organizational community sources had to be consulted and several methods had to be employed. The organizational activities and stakeholders' needs had to be identified to determine the objectives, facets, and the subject coverage of the taxonomy. Main categories were determined by identifying the stakeholders' interests and consulting organizational community sources and domain taxonomies. Category terms were selected from terminologies of classification schemes, domain taxonomies, and thesauri against the stakeholders' interests. Hierarchical structures of the main categories were constructed in line with the stakeholders' perspectives and the navigational role taking advantage of structures/term relationships from classification schemes and thesauri. Categories were determined in line with the concepts and the hierarchical levels. Format of categories were uniformed according to a commonly used standard. The consistency principle was employed to make the taxonomy structure and categories neater. Validation of the draft taxonomy through consultations with the stakeholders further refined the taxonomy.Originality/valueNo similar study could be traced in the literature. The steps and methods used in the taxonomy development, and the information studies taxonomy itself, will be helpful for library and information schools and other similar organizations in their effort to develop taxonomies for organizing content and aiding navigation on organizational sites.

The article relates how the Brooklyn Campus Library of Long Island University, despite limitations of physical distance and the varying conditions of the remote graduate campus at Westchester, makes every effort to face each challenge creatively with practical solutions for implementation. We share our findings and experiences—what worked and what did not—and what remains to be done in terms of supporting the curricula and bringing library resources and services to a mixture of remote site users. The authors recount how the gap between reality and the ideal is reduced and unique issues relevant to remote users are resolved by the Brooklyn Campus Library, in collaboration with other units of Long Island University. We relate how we combine library instruction with our marketing efforts to promote library resources and services. We also analyze survey data and interlibrary loan statistics to assess our success. The article contributes to the ongoing discussion of improving and promoting library res...

PurposeThe purpose of the paper is to describe the Long Island University Brooklyn Campus Library's experience with a Smart Space Project. This paper recounts how the library creates new instructional spaces, through the use of smart technologies. This study illustrates challenges facing the library, recounts collaboration with other campus units, and describes support service provided by Library Information Technology. This account contributes to the sharing and discussion of experiences among modern academic libraries regarding needs assessment, space planning, and utilization of technology to support library services.Design/methodology/approachThe literature review includes space planning, building renovation and construction, and instructional technology. Various aspects of the Smart Space Project are described and analyzed. Studies and experiences from other academic libraries are also discussed.FindingsSpace renovation projects may be complex, requiring a systematic approach encompassing vision, needs assessment, funding, planning, technological considerations, and collaboration with other campus units. Creativity, flexibility, open‐mindedness, and attention to details are keys to the success of renovation projects.Research limitations/implicationsIn the areas of library space, student learning behaviour, utilization of technology, and smart technology's impacts on online/distance library instruction, more research needs to be conducted.Practical implicationsThis account provides useful information and first‐hand experience for library administrators and faculty planning instructional space projects.Originality/valueThis article provides a snapshot of the efforts of a mid‐sized urban library to address issues of limited space, budgetary constraints, growing collections, and increasing user needs. It provides practical lessons and suggestions for other library administrators and faculty seeking to make building and instructional technology improvements. It also offers valuable information for library information technology units implementing smart instructional projects.

The E690 grade offshore platform steel was obtained by top and bottom blowing converter, curved spray continuous casting machine and thermo-mechanical control processing (TMCP). The static continuous cooling transformation curves (CCT curves) of the rolled plate were drawn by adopting thermal expansion method and metallographic analysis. The microstructures at different cooling rates were observed by optical microscope (OM) and scanning electron microscope (SEM). Results showed that the super-cooled austenite in tested steel was relatively stable and there was little high temperature microstructure transformation at the cooling rate of 0.1°C/s. The regression model of phase transformation temperature and cooling rates were obtained. According to the results of orthogonal experiment, the most optimal heat treatment process was firstly heated at 890 °C, wind cooling and then tempered at 630 °C for 60 min.

Mitochondrial uncoupling proteins (UCPs) play crucial role in the regulation of metabolic thermogenesis, photosynthesis, redox poise, and response to stress situations. However, the involvements UCPs and its regulatory mechanisms in plant mitochondrial respiration and electron transport have not yet been fully substantiated. In this article, we show that UCP is essential for effective respiratory balance and mitochondrial electron transport poise under chilling stress in tomato. Compared with pTRV (non-silenced) plants, suppression of LeUCP the expression by virus-induced gene silencing significantly decreased the total, SHAM-resistant, and CN-resistant respiratory rates, but increased cytosolic glycolysis pathway-related gene expression and enzymes’ activities under chilling stress. The transcripts’ abundances of UCRH, COX1, COX2, AOX1a, AOX2, and NDC1 genes involved in main and bypass miETC components were decreased, while those of NDUO and SDH4 were slightly increased in the leaves of LeUCP-silenced plants. In addition, silencing of LeUCP aggravated H2O2 and O2 − accumulation levels in leaves under chilling stress. Our results provide strong evidence that LeUCP is critical for respiratory homeostasis and mitochondrial electron transport signaling under chilling stress in tomato.

Deoxynivalenol (DON) is a group B trichothecene and a common contaminant of crops worldwide. This toxin is known to cause a spectrum of diseases in animals and humans such as vomiting and gastroenteritis. Importantly, DON could inhibit the synthesis of protein and nucleonic acid and induce cell apoptosis in eukaryote cells. The transduction of signaling pathways is involved in the underlying mechanism of the cytotoxicity of DON. Mitogen-activated protein kinase and Janus kinase/signal transducer and activator of transcription seem to be two important signaling pathways and induce the inflammatory response by modulating the binding activates of specific transcription factors. This review mainly discussed the toxic mechanism of DON from the vantage point of signaling pathways and also assessed the profiles of DON and its metabolites in humans. Importantly, we conducted a human exposure risk assessment of DON from cereals, cereal-based foods, vegetables, water, and animal-derived foods in different countries. Some regular patterns of DON occurrence in these countries are suggested based on an analysis of global contamination with DON. This review should provide further insight for the toxic mechanism study of DON and human exposure risk assessment, thereby facilitating mycotoxin control strategies.

Bibliographic tools were used to build an organizational taxonomy in the information studies domain. A classification scheme, three thesauri of indexing terms, and two do-main taxonomies were used to collect categories related to the Information Studies Taxonomy. Classification schemes and thesauri were found helpful in creating the structure and identifying ...Des outils bibliographiques ont été utilisés pour construire une taxinomie organisationnelle dans le domaine des sciences de l’information. Un système de classification, trois thésaurus de termes d’indexation et deux taxinomies du domaine ont été utilisés pour définir les catégories liées à la taxinomie des sciences de l’information. Les systèmes de classification et les thésaurus ont été jugés utiles pour la création de la structure et la définition…

At present, qualitative and quantitative analyses of the soil microstructure are mainly made on the two-dimensional level. The present study makes possible the three-dimensional visualization of soil microstructure by transforming the scanning electron microscopy (SEM) photographs into the three-dimensional digital map (DEM) with such abundant information as their inherent particles and apertures; it also makes available 2.560 as the fractal dimension for the DEM image of the sample soil by conducting a quantitative analysis of its microstructure with the projective covering method, a surface fractal measurement method.

Power system transient stability is one of the most challenging technical areas in electric power industry. Thyristor-controlled series compensation (TCSC) is expected to improve transient stability and damp power oscillations. TCSC control in power system transients is a nonlinear control problem. This paper presents a T–S-model-based fuzzy control scheme and a systematic design method for the TCSC fuzzy controller. The nonlinear power system containing TCSC is modelled as a fuzzy “blending” of a set of locally linearized models. A linear optimal control is designed for each local linear model. Different control requirements at different stages during power system transients can be considered in deriving the linear control rules. The resulting fuzzy controller is then a fuzzy “blending” of these linear controllers. Quadratic stability of the overall nonlinear controlled system can be checked and ensured using H ∞ control theory. Digital simulation with NETOMAC software has verified that the fuzzy control scheme can improve power system transient stability and damp power swings very quickly.

A fuzzy logic rule-based damping controller for STATCOM has been proposed in this paper. The proposed controller has two control loops. One is voltage control, with traditional PI control; the other is damping control, with the proposed rule-based controller. The input signal to the voltage control loop is the terminal voltage, and the input signal to the damping control loop is the generator speed, which can calculated from local variables. The effectiveness of the proposed controller was demonstrated in a single machine infinite bus system with Siemens NETOMAC. Further study will focus on the control strategy of STATCOM on multi-machine system.

For the purpose of Static Synchronous Compensator (STATCOM) control, an improved PI control method is developed based on fuzzy set and auto-tuning techniques. A fuzzy rule base is used to adapt the parameter varying characteristics of the power system and various operation points of STATCOM. The relay-based auto-tuning scheme is used to find out the appropriate PI gains with respect to a set of operating points, consequently to facilitate the establishment of the desired fuzzy rule base. To test this control strategy, digital simulation on MATLAB as well as field experiments on a real ±10kvar STATCOM developed in Tsinghua University has been done. Both the results show that the proposed control strategy is much more effective than fixed parameter PI control.

Fast valving has long been regarded as an effective and economical method of performing transient control in a power generation plant. Due to the inherent nonlinearities that exist in this operation, fast valving controllers designed in a conventional way cannot deliver satisfactory control. This paper introduces a new approach to construct a fast valving controller by applying an adaptive fuzzy technique. A rule-generation and adaptation scheme is formulated in a fuzzy-system framework. Then the implementation issue is discussed in detail. From the outcome of on-line testing, it is shown that the controller constructed in this way not only maintains global stability, but also appears to be robust in different fault situations.

This paper presents an artificial neural-network-based controller to realize the fast valving in a power generation plant. The backpropagation algorithm is used to train the feedforward neural networks controller. The hardware implementation and the test results of the controller on a physical pilot-scale power plant setup are described in detail. Compared with the conventional fast valving methods applied to the same system, test results both with the computer simulation and on a physical pilot-scale power plant setup demonstrate that the artificial neural network controller has satisfactory generalization capability, reliability, and accuracy to be feasible for this critical control operation.

Based on the zero-sequence component of the reference voltages, this paper comprehensively analyzes the neutral-point variation and balancing control for three-level neutral-point-clamped inverter. An analytical method is proposed to accurately calculate the injected zero-sequence voltage for NP balancing. Based on the analytical analysis, the limitation of NP balancing control is revealed and the NP-fully-controllable region is presented. A real-time NP balancing algorithm is proposed as well. The feasibility of the proposed method is verified using simulation results for a 6 kV/1800 kVA medium voltage drive.

Power quality disturbances (PQD) are normally monitored by dedicated PQ devices. The devices capture disturbances' waveform in real-time. Magnitude is accepted as a significant index for detection, general classification and later assessment analysis. To choose a suitable way of magnitude characterization is a fundamental work of PQD measuring and monitoring. This study presents three different ways, RMS voltage, peak voltage and fundamental voltage component, to determine magnitude. The algorithms of the three approaches implemented in Matlab are introduced. The algorithms are FFT-based and wavelet transformation (WT) based. A voltage sag benchmark in a radial test system is used to verify and validate the study. The depth-duration characterization of voltage sags is illustrated. The most appropriate approach is suggested at the end of the paper according to the practical monitoring or measuring requirements. The research result is applied to a new PQ monitor with DSP infrastructure being developed by us. The proper window length selection and technique to avoid oscillation is also discussed in the rest of the paper. The information obtained from the magnitude characterization can be furthered to extract features for PQD detection and classification.

Power systems are undergoing improvements and development in computing technology and assessment tools. For a multi-machine power system, transient stability simulation has been believed as an indispensable tool for planning, design, operation and research. The model of a synchronous generator is considered the most important factor which influence the simulation result. In this paper, two types of synchronous generator model are discussed according to their complexity. Digital simulation of an actual system of North China Power System is fulfilled to study the different characteristics of the two models and a comparison is also made.

Static VAr compensators (SVCs) are the fastest and most widely applied FACTS devices at present. However, the SVC's high speed control can only be applied effectively if the type and size of the power components as well as the control and protection schemes are well matched to the specific network configuration and operation requirements. The combination of intensive computer and advanced real-time simulation is of great benefit for the design verification of new FACTS application. This paper presents the use of an RTDS simulator for the real-time testing of an SVC controller. It is a pure digital simulator for the SVC project and special measures have been taken to improve the precision of firing angle for TCRs. Some results of a SVC project study are presented.

The thyristor controlled series compensator (TCSC), composed of a capacitor in parallel with a thyristor controlled reactor (TCR), is a variant topology circuit. For such circuits there is no universal method to build the analytical mathematical model. The paper focuses on building an analytical model by the method of "topology" to describe the dynamic behavior of TCSC. Based on the model, the steady-state model is derived and the dynamic characteristics are discussed. The model is verified by digital simulation and the method can be extended to similar devices and be used for optimizing the control systems.

A /spl plusmn/20 MVAr STATCOM (static synchronous compensator) using GTO technology was commissioned in China in 1998. The STATCOM is designed to supply fast voltage control and to enhance the damping of inter-area electromechanical oscillations of the system. In this paper, by investigating the added synchronizing and damping torque induced by STATCOM, the conflicts between these control objectives are analyzed and the limitations or even invalidity of the fixed-parameters damping controller for certain system parameters and load conditions is discussed. A rule-based controller, which employs bang-bang, fuzzy logic or fixed-parameter PI control strategy according to the operation state of the system, is designed. The advantages of the proposed controller over the fixed-parameter PI controller are demonstrated by nonlinear digital simulations.

The first thyristor controlled series compensation (TCSC) project in China is expected to be applied to the Yimin-Fengtun 500 kV transmission line in the Year 2000 to improve its transmission capability. As a part of the project's feasibility study, this paper focuses on the steady-state and dynamic characteristics of TCSC based on digital simulations and physical experiments. It is necessary to comprehend the characteristics of TCSC devices for modeling TCSC correctly and proposing an effective transient control strategy. The paper studies the following several characteristics of TCSC: the steady-state characteristics in four typical operation modes; the operation symmetry under various control modes; the differences between closed-loop and open-loop impedance control; and the influences of different synchronizing signals on dynamic characteristics of impedance variations.

Thyristor controlled series compensation (TCSC) is expected to provide various benefits to power systems, including transient stability improvement, subsynchronous resonance (SSR) mitigation, power swings damping, fault current reduction, etc. Grasping the characteristics of TCSC installations and ending effective firing control strategies are essential to implement these advantages. This paper studies two important aspects of TCSC characteristics, the time constant of TCSC dynamic response and impacts of reference signals for thyristor firing angles on TCSC dynamic response. Closed-loop impedance control is proposed to speed the dynamic response of TCSC. A "two-stage" firing control method is presented to accomplish smooth switching between the capacitive region and inductive region. Both digital simulations with EMTDC/PSCAD software and physical experiments are employed in the study.

A desirable transient stability control scheme should be able to ensure the first-swing stability as well as provide effective damping. This paper presents a T-S model based fuzzy control scheme for thyristor controlled series compensation (TCSC) in power system transients. The nonlinear power system containing a TCSC is modelled as a fuzzy "blending" of a set of locally linearized models. A linear optimal control is designed for each local linear model. Different control requirements at different stages during power system transients can be considered in deriving the linear control rules. The resulting fuzzy controller is then a fuzzy "blending" of these linear controllers. Furthermore, a gradient descent algorithm is put forward to modify the rule truth factors for optimization. For convenient industrial realization of the fuzzy control scheme, a practical approach requiring only local signals is also described. Simulation with NETOMAC software has verified the effectiveness of the fuzzy control scheme.

The Takagi-Sugeno model (T-S model) based fuzzy control scheme for nonlinear systems is presented in this paper. In the T-S fuzzy model, a nonlinear system is represented with a set of fuzzy rules which describe the local linear dynamics. Then the parallel distributed compensation (PDC) design is employed in the fuzzy controller design. Linear optimal control is used in the derivation of each control rule. The overall fuzzy controller is a fuzzy blending of each individual linear controller. Quadratic stability of the overall nonlinear control system can be checked and ensured with H/sup /spl infin// control theory. The fuzzy control scheme is applied to thyristor-controlled series compensator control in power system transients. Digital simulations with NOTOMAC software have demonstrated that the fuzzy control scheme is superior to other conventional control methods. The fuzzy controller effectively improves power systems transient stability and very quickly damp power swings.

The operational performance of static synchronous compensators (STATCOMs) under unbalanced and distorted system voltage is a great concern of designers and operation engineers. Based on a novel per-unit STATCOM mathematical model, this paper makes a theoretical analysis of STATCOM performance under distorted system voltage. Algebraic expressions as well as the 3-D curves are given to reveal the relationship between STATCOM harmonics and the main circuit parameters. The theoretical analysis was verified by digital simulation results of PSCAD/EMTDC and tests on a 10 kVAr prototype experimental device. The good agreement between the analytical results and the experimental results show that the approach proposed in this paper can be used to select the passive elements and assess the operation performance of STATCOM under unbalanced or distorted system voltage.

This paper presents the results of physical experiments on a /spl plusmn/10 kVAr STATCOM model developed by Tsinghua University of China, which is the prototype of a /spl plusmn/20 MVAr STATCOM to be commissioned in the Henan province of China. A series of physical experiments, including open/closed loop step response, pulse-blocking under severe disturbances, voltage regulation improvement, voltage stabilization under surge loads, power system stability limits enhancement and damping improvement of power swings, were performed on the model to simulate the performance of the STATCOM in a real power system. The conclusions derived in the laboratory are expected to be helpful to the operation of the /spl plusmn/20 MVAr STATCOM in the near future.

This paper is a summary of our research work for seven years in applying the theory of optimal control to the excitation system of a generator (Optimal Excitation Controller, OEC). It analyzes problems of OEC by means of digital simulating and physical modelling. It also points out the merits of OEC and what research works should be done in the future.