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Author(s):  
Shigeru Koda ◽  
Yuichi Takabayashi ◽  
Tatsuo Kaneyasu ◽  
Yoshitaka Iwasaki

Abstract The intensification effect of edge radiation due to the periodic alignment of three-pole wigglers was analytically and numerically investigated. The radiation properties were studied using a simple model that had an alternating alignment of straight sections and large gradient orbit sections due to the use of three-pole wigglers. The angular distribution of the radiation was concentrated on a concentric circle. The peak intensity of the radiation was roughly on the same order as that of the peak radiation of a planar undulator. The spectrum of the radiation had a characteristic structure that was rather similar to the higher harmonic structure of undulator radiation. A numerical study showed that a planar undulator with a specific K value satisfies approximately the radiation intensification condition due to the periodic alignment of the three-pole wigglers. The intensified edge radiation is included in the undulator radiation.


2022 ◽  
Vol 12 ◽  
Author(s):  
Weijia Yang ◽  
Citing Li ◽  
Xuesong Gao

Relational agency is pivotal for understanding how language teachers seek and utilize relational resources in different contexts and grow to be agents of change amid various educational challenges. This study explored how three university teachers of Chinese as a second language (CSL) enacted their relational agency to enhance their research capacity and sustain their professional development. Data on their personal network development was collected through concentric circle interviews, life-history interviews and written reflections over three months. Thematic analysis was adopted for iterative coding and interpretation of the data. The findings revealed that teachers’ personal networks provided them with value guidance, emotional support and academic support, which exerted differential levels of impact on them to make agentic choices and actions. The study suggests that personal network analysis may serve as a suitable theoretical lens to achieve a multi-layered understanding of relational agency. The study also calls for more efforts to create learning opportunities and spaces in the relational context for teachers to build their career as agentic academics in language teacher education and development programs.


2022 ◽  
Author(s):  
Simon Guilliard

The Brexit experience sheds new light on the question of whether credible state aid regulation must by its nature be supranational. Following a review of the disciplines of EU state aid law and WTO subsidy law, which shape international subsidy law, it is explained why the introduction of bi- and plurilateral control regimes beyond the WTO is necessary from the EU's point of view and which hurdles these efforts must overcome. Finally, on the basis of an overall analysis of EU (free trade) agreements, a concentric circle model of state aid law is developed, which reveals the link between type of agreement, market integration, geographical proximity and the impact of EU law on the state aid rules agreed with the treaty partners.


2021 ◽  
Vol 12 (6) ◽  
pp. 687-695
Author(s):  
Y. Chandra Mohan ◽  
◽  
L. Krishna ◽  
S. Sreedhar ◽  
B. Satish Chandra ◽  
...  

An investigation was carried out on fifteen rice genotypes to identify stable rice hybrids across six different agroclimatic zones in Telangana state using AMMI and GGE bi-plot analyses during July to November, 2020. Analysis of variance clearly showed that environments contributed highest (65.47%) in total sum of squares followed by genotypes×environments (21.19%) indicating very greater role played by environments and their interactions in realizing final grain yield. AMMI analysis revealed that rice hybrids viz., RNRH 39 (G6), 27P31 (G14) and RNRH 15 (G1) were recorded higher mean grain yield with positive IPCA1 scores. The hybrids, JGLH 275 (G11) and JGLH 365 (G15) were plotted near to zero IPCA1 axis indicating that these hybrids are relatively more stable across locations. GGE bi-plot genotype view depicts that the hybrids, JGLH 365 (G15) and US 314 (G8) were inside the first concentric circle and found to be more stable across environments. GGE bi-plot environment view showed that Rudrur (E4) location was the most ideal environment. However, Warangal (E6) and Jagtial (E1) locations were poor and most discriminating. Depending on dispersion of environments in different directions, six locations were partitioned into three mega zones as first zone comprised of four locations viz., Kunaram (E2), Kampasagar (E3), Rudrur (E4) and Rajendranagar (E5) whereas highly dispersed Jagtial (E1) and Warangal (E6) were identified as two separate mega environments. The bi-plot view identified that 27P31 (G14), JGL 24423 (G2) and RNRH 39 (G6) were the best performing genotypes in first zone comprising four locations.


Plant Disease ◽  
2021 ◽  
Author(s):  
Hafiz Husnain Nawaz ◽  
Rafiq Dogar ◽  
Muhammad Ijaz ◽  
Ashraf Sumrah ◽  
Kamil Husnain ◽  
...  

Anthracnose symptoms on olive (Olea europaea) fruits cv. “Gamlick” were found in farmer orchards in Chakwal, Punjab, Pakistan (32° N and 72° E), with an average prevalence of 59%. Fruit symptoms start as thin, black, sunken lesions with a watery appearance that grow in diameter and coalesce into a large sunken soft zone. Lesions on mature fruit become noticeable in 5 to 6 days after infection, if temperatures are favorable (28°C). On the fruit lesion, orange conidial masses in dispersed or concentric circle arrangement can appear. Fragments (5 mm) were taken from the margins of fruit lesions and surface-sterilized with 70% ethanol (1 min) and 1% NaClO (2 min), cleaned with sterile purified water, blotted dry, and plated on potato dextrose agar (PDA) in Petri dishes. The petri plates were incubated at 27°C. A fungus was consistently isolated, and thirty-five isolates were characterized. Aerial mycelia from olive isolates Colonies were compact, initially white or cream white, then grey, and eventually dark grey, with conidium masses forming in the middle. Mycelium is branched, septate, and hyaline. Conidia are hyaline, aseptate, fusiform, or often cylindrical, with obtuse apices and tapering bases. Their mean size was 8.5µm in length and 3.0 µm in width. Based on morphological features, the fungus was tentatively identified as Colletotrichum acutatum (Agosteo G.E., 2010). The identification was confirmed by amplification and sequencing of a representative isolate's internal transcribed region (ITS), Beta- tubulin region (TUB2), Actin region (ACT), and Glyceraldehyde 3-phosphate dehydrogenase region (GAPDH) with the primers ITS1/ITS4 (Gardes & Bruns 1993), TUB4/TUB5 (Woudenberg et al. 2009), ACT1/ACT3 (Carbone & Kohn 1999) and GDF1/GDR1 (Guerber et al. 2003). BLAST analysis revealed 100% identity for ITS, GAPDH and ACT and 99% identity for TUB, between the sequences of the olive fruit isolate (GenBank Accessions MW647502, MZ436968, MZ714412 and MW810331, respectively) and sequences of C. acutatum reference isolates (GenBank Accessions GO613492, KF975660.1, MT274752.1 and MH547616 respectively). Phylogenetic analysis based on ITS, GAPDH and TUB regions of the olive fruit isolates and reference isolates of various Colletotrichum species using the MEGA X software program confirmed the isolate from olive was C. acutatum. The fungal isolate was deposited as a living culture in the Barani Agricultural Research Institute's fungal culture collection center (BACA.9381). Pathogenicity tests were conducted with this isolate by placing a 20 µl drop of a conidial suspension (3 × 107conidia ml−1) on five healthy olive cv. Gemlik fruits. As a control, five non-inoculated olive fruits were used. Fruits were placed at a temperature of 27°C with artificial light and a photoperiod of 12 hours. Anthracnose symptoms developed only on inoculated fruits after seven days of inoculation. The fungus was re-isolated from symptomatic fruits, and its identity was confirmed through morphological characteristics, thus verifying Koch's postulates. To the best of our knowledge, this is the first report of C. acutatum infecting olive fruits in Chakwal region of Pakistan.


2021 ◽  
Vol 3 (1) ◽  
pp. 163-182
Author(s):  
Sándor Varga

Abstract The exact definition of the Mezőség/Câmpia Transilvaniei/Transylvanian Plain, hereafter Plain, as a region with an independent folk culture having a coherent internal structure is still a subject of debate among ethnographers. Some of them regard certain small regions (Borsa/Borșa Valley, Kis and Nagy Szamos/Someșul Mic și Someșul Mare etc.) as belonging to the Mezőség/Plain, while others do not. I distinguish a central group of the villages in the Mezőség/Plain region (Belső-Mezőség or Central Plain: e.g. Visa/Vișea, Magyarpalatka/Pălatca, Katona/Cătina, Pusztakamarás/Cămăraşu) from the rest of the territory, similarly to György Martin, István Pávai and László Barabás, relying on material culture and folklore research, as well as my own investigations. When advancing outward from this core area, the concentric circle of so-called peripheral areas follow (the West, North, East and South Plain/Mezőség), reaching the boundaries on the edges of the region: Nagy Szamos/Someșul Mare Valley, Lápos/Lăpuș Valley, Sajó/Șieu Valley, Maros/Mureş Valley, Marosszéki1 Mezőség/Mureș Seat Plain, Erdőalja/Sub Pădure area, Borsa/Borșa Valley, and Kis Szamos/Someșul Mic Valley. A further, smaller group of villages can be distinguished in the area of Belső-Mezőség/Central Plain by their dance and music culture; for the regular weekend dance events of these villages, organised by local youths in the 1960s, Roma musicians of Magyarpalatka/Pălatca would play the music. I assign the name Palatka dance district to this area in my paper.


Plant Disease ◽  
2021 ◽  
Author(s):  
Jin Sun ◽  
Guo Qin Wang ◽  
Jia Ge Song ◽  
Biao Xu

Geranium (Pelargonium × hortorum) is an ornamental plant cultivated throughout world. In May 2019, typical symptoms of rust with nearly 90% disease incidence were observed on leaves of Pel. × hortorum growing in pots in a scenic spot in the ancient city of Kashgar, Xinjiang province, China. Early symptoms of the disease appeared small lesions with pale-yellow halos on the lower leaf surfaces. Infected tissues subsequently formed a concentric circle of sori on lesion reaching a final diameter of 0.5 to 1.5 cm, which resulted in leaf blighting and premature. Two representative specimens were deposited in the Mycological Herbarium of Tarim University (HMUT 8001 and HMUT 8002). Urediniospores were globose or subglobose to ovoid, light brown, echinulate, thin-walled with two conspicuous subequatorial pores, 19.8 to 27.3 × 17.8 to 23.6 μm (24.3 × 21.7 μm average, n=30). Telia and teliospores were not seen. The sizes and characteristics of urediniospores were similar with those of Puccinia pelargonii-zonalis as described by Doidge (1926). To confirm the identification, genomic DNAs were extracted directly from sori on diseased leaves from isolates HMUT 8001 and HMUT 8002. The part of the nuclear large subunit (LSU, 28S) rDNA was amplified and sequenced following Aime et al. (2006), and deposited in GenBank (Accession Nos. MT648851 and MT648852). An NCBI blast search indicated that 99.6% identity of the LSU (772/775 nucleotides) with Puc. pelargonii-zonalis on Pel. hortorum (KX999887) from Australia (Marin-Felix et al. 2017). The phylogenetic analysis based on the LSU sequences using Maximum-Likelihood and Bayesian methods placed the Xinjiang isolates from Pel. × hortorum in the same clade with the reference sequences of Puc. pelargonii-zonalis. Pathogenicity test was confirmed by Koch’s postulates. Leaves of three healthy potted plants were sprayed with a spore suspension (2 × 105 spores/ml). Sterile water was sprayed on three healthy seedlings as controls. Inoculated and control plants were covered with a plastic bag and placed in a moist chamber with 90% relative humidity at 25°C. Initial symptoms were observed with small light-yellow spots on the upper surface after 15 days, but not in the control plants. Puc. pelargonii-zonalis has been previously reported on Pel. × hortorum in Argentina, Australia, Canada, Georgia, Greece, India, Mexico, New Zealand, Norway, Portugal, South Africa, the United States, and Venezuela (Farr and Rossman 2021). Geranium rust was first found in Yunnan province in southwestern China (Zhou and Zhuang 2005). However, this is the first report of geranium rust in Xinjiang province in northwestern China. The occurrence of the disease seriously affected their ornamental and economic value.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Fei Hao ◽  
Jinjiang Su ◽  
Jingjing Shi ◽  
Chaohan Zhu ◽  
Jiatong Song ◽  
...  

AbstractA high-precision camera intrinsic parameters calibration method based on concentric circles was proposed. Different from Zhang’s method, its feature points are the centers of concentric circles. First, the collinearity of the projection of the center of concentric circles and the centers of two ellipses which are imaged from the concentric circles was proved. Subsequently, a straight line passing through the center of concentric circles was determined with four tangent lines of concentric circles. Finally, the projection of the center of concentric circles was extracted with the intersection of the straight line and the line determined by the two ellipse centers. Simulation and physical experiments are carried out to analyze the factors affecting the accuracy of circle center coordinate extraction and the results show that the accuracy of the proposed method is higher. On this basis, several key parameters of the calibration target design are determined through simulation experiments and then the calibration target is printed to calibrate a binocular system. The results show that the total reprojection error of the left camera is reduced by 17.66% and that of the right camera is reduced by 21.58% compared with those of Zhang’s method. Therefore, the proposed calibration method has higher accuracy.


2021 ◽  
Vol 12 ◽  
Author(s):  
Ruili Wei ◽  
Jianyang Xie ◽  
Huihui Wu ◽  
Fangping He ◽  
Fangxia Meng ◽  
...  

Purpose: We examined the macular microvascular changes of the macula in neuromyelitis optica spectrum disorder (NMOSD) patients and its association with their disability and other clinical variables.Methods: Thirty-four NMOSD (13 patients without optic neuritis, NMOSD-NON, and 21 patients with a history of optic neuritis, NMOSD-ON) and 44 healthy controls (HCs) were included in the study. Optical coherence tomographic angiography (OCTA) was used to image the superficial (SCP), deep (DCP), and whole capillary plexus (WCP) in a 2.5-mm-diameter concentric circle [excluding the foveal avascular zone (FAZ)]. An algorithm (Dbox) was used to quantify the complexity of the three capillary layers by fractal analysis. We also evaluated the expanded disability scale status (EDSS).Results: Dbox values were significantly reduced in SCP (p < 0.001), DCP (p < 0.001), and WCP (p = 0.003) of NMOSD when compared with HCs. Dbox values were significantly reduced in NMOSD eyes with optic neuritis when compared with healthy controls (p < 0.001) and eyes without optic neuritis (p = 0.004) in the SCP. In the DCP, eyes with optic neuritis showed significantly reduced Dbox values when compared with eyes without optic neuritis (p = 0.016) and healthy controls (p < 0.001); eyes without optic neuritis showed significantly reduced Dbox values (p = 0.007) in the DCP when compared with healthy controls. A significant negative correlation (Rho = −0.475, p = 0.005) was shown between the superficial macula Dbox values and the EDSS in NMOSD patients. Additionally, a negative correlation (Rho = −0.715, p = 0.006) was seen in the superficial Dbox values in [e]eyes without optic neuritis and EDSS.Conclusions: Macular microvascular damage in the superficial plexus is associated with disability in NMOSD. Macular microvascular alterations arise independently of the occurrence of ON in NMOSD.


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