1,721,700 research outputs found
Advances in medical imaging and gamma ray spectroscopy
No full textThis thesis describes some results from the research by the author in his three year PhD period. The work presented can be divided into two major areas--developing detectors for Positron Emission Tomography and the application of gamma ray spectroscopy based on scintillation detectors. In recent years, great effort has been made to improve the performance of PET instrumentation. As a result, some new concepts were introduced in the design of modem PET systems. Several small and dedicated PET systems have been developed which are aimed to provide better cost effectiveness and image quality. Detectors with Depth-of-interaction capability helped to reduce the degradation of PET image quality due to the parallax error. In order to overcome some intrinsic limitations of PET, such as the relatively poor spatial resolution, PET systems compatible with other imaging modalities like MRI, CT and SPECT enables one to combine the quantitative information provided by PET and the structural (anatomical) information from MRI or CT. A Positron Emission Mammography system was designed for breast cancer imaging application. It can be placed inside an existing MR imaging system currently used in Royal Marsden Hospital. The PET detector was designed to work simultaneously with the MRI system. The Electromagnetic Interference (EMI) between the two imaging systems can be minimised by placing the conducting material, such as the read-out electronics for PET, outside the MRI system. In this design, the scintillation crystals are connected to the remote photodetectors through fibre light-guides of 2m in length. A comprehensive feasibility study based on both Monte Carlo simulation and experimental measurements was carried out. For research applications such as small animal PET imaging, we developed a Depth-of-interaction (DOI) PET detector based on the Hybrid Photodiode (HPD). A prototype detector was constructed and tested. The results show a DOI resolution of 5-8mm and a timing resolution better than 5ns. The second part of this thesis presents the work in gamma ray spectroscopy. A number of algorithms for unconstrained spectrum de-convolution were compared using both simulated and measured data. The application of this technique on energy- loss spectra collected using a 3" Nal scintillation counter shows huge improvement in both energy-resolution and effective detector sensitivity. This makes it possible to use such a detector as a replacement for HPGe spectrometers for some applications. The work in gamma ray spectroscopy also led to the development of a range of large volume scintillation detectors, which provided much-improved energy-resolution compared with the standard 3" Nal detectors. These detectors were shown to be ideal detectors for use in conjunction with the spectrum de-convolution process.</p
Review of the genus Larnaca Walker, 1869 from China (Orthoptera: Gryllacrididae: Gryllacridinae)
No full textYin, Zi-Xu, Meng, Ling-Xin (2021): Review of the genus Larnaca Walker, 1869 from China (Orthoptera: Gryllacrididae: Gryllacridinae). Zootaxa 5027 (4): 587-596, DOI: 10.11646/zootaxa.5027.4.
FIGURE 3 in Review of the genus Larnaca Walker, 1869 from China (Orthoptera: Gryllacrididae: Gryllacridinae)
No full textFIGURE 3. Abdominal apex of Larnaca (Larnaca) emarginata. A. lateral view; B. ventral view; C. ovipositor; D. dorsal view. A–C. female; D. male.Published as part of Yin, Zi-Xu & Meng, Ling-Xin, 2021, Review of the genus Larnaca Walker, 1869 from China (Orthoptera: Gryllacrididae: Gryllacridinae), pp. 587-596 in Zootaxa 5027 (4) on page 590, DOI: 10.11646/zootaxa.5027.4.7, http://zenodo.org/record/545348
FIGURE 9 in Review of the genus Larnaca Walker, 1869 from China (Orthoptera: Gryllacrididae: Gryllacridinae)
No full textFIGURE 9. Distribution map of the genus Larnaca from China.Published as part of Yin, Zi-Xu & Meng, Ling-Xin, 2021, Review of the genus Larnaca Walker, 1869 from China (Orthoptera: Gryllacrididae: Gryllacridinae), pp. 587-596 in Zootaxa 5027 (4) on page 595, DOI: 10.11646/zootaxa.5027.4.7, http://zenodo.org/record/545348
Meng Ling Kuan, jongleur de jarres : Troupe du cirque acrobatique de Chang-Hai (ou Shanghai Chine)
No full textL’acrobatie chinoise est née il y a cinq millénaires et son berceau serait le district agricole de Wu Qiao situé à 200 km au sud de Pékin. En Chine, les spectacles acrobatiques relèvent du Baixi , littéralement des représentations face à un public, et sont présentés dans des théâtres. Les premières troupes acrobatiques sont fondées dans les années 1950 dans la foulée de la création de la Troupe nationale. La troupe acrobatique de Shanghai se constitue en 1951 et devient très vite l’une des plus puissantes du pays. La sélection des aspirants acrobates se fait à intervalle régulier, tous les sept ans environ, et de nombreux enfants se présentent aux portes des troupes en espérant y trouver à la fois un métier et la gloire de servir la patrie. Aujourd’hui, le recrutement s’est élargi et certaines troupes s’attachent à engager des groupes entiers d’enfants pour les former comme une troupe à part entière. Issue d’une pratique très populaire initialement présentée dans la rue, la manipulation de jarres, comme plusieurs disciplines chinoises, s’appuie sur des objets usuels et est progressivement devenue prétexte à des jeux virtuoses individuels ou collectifs. Le journaliste Jacques Richard commente le travail de Meng Ling Kuan lors du passage de la troupe à Paris en mai 1973, dans un article de L’Aurore du 12 mai 1973, intitulé « Au cirque acrobatique de Chang-Hai, un vélo pour douze et un charmeur de jarre » :
« Mais s’il fallait, de ce programme impressionnant bien que légèrement monotone, ne retenir qu’un numéro, c’est peut-être à Meng Ling Kuan que devrait aller la préférence : seul sur l’immense plateau, vêtu de velours noir, aux prises avec une énorme et pesante jarre, ce jongleur de force lance, relance, rattrape sur le crâne l’objet qui tourbillonne et danse entre ses mains charmeuses avec des grâces d’oiseau blanc. » Source : Jacques Richard, Trente ans de chroniques de cirque en France, 1968-1997 , 2018, p. 75.téléchargeabl
Dinoderus (Dinoderus) ochraceipennis Lesne 1906
No full textDinoderus (Dinoderus) ochraceipennis Lesne, 1906 Fig. 13 (A, B) Dinoderus ochraceipennis Lesne, 1906: 399. Distribution in China. First recorded from Yunnan by Liu (2010). Other distribution. Myanmar, Vietnam. Host plants. Unknown.Published as part of Zhang, Yi-Feng, Meng, Ling-Zeng & Beaver, Roger A., 2022, A review of the non-lyctine powder-post beetles of Yunnan (China) with a new genus and new species (Coleoptera: Bostrichidae), pp. 501-545 in Zootaxa 5091 (4) on page 515, DOI: 10.11646/zootaxa.5091.4.1, http://zenodo.org/record/586382
FIGURE 13 in A review of the non-lyctine powder-post beetles of Yunnan (China) with a new genus and new species (Coleoptera: Bostrichidae)
No full textFIGURE 13. (A, B) Lateral (A) and dorsal (B) views of Dinoderus (Dinoderus) ochraceipennis Lesne, 1906. Total horizontal scale bar of B =1 mm.Published as part of Zhang, Yi-Feng, Meng, Ling-Zeng & Beaver, Roger A., 2022, A review of the non-lyctine powder-post beetles of Yunnan (China) with a new genus and new species (Coleoptera: Bostrichidae), pp. 501-545 in Zootaxa 5091 (4) on page 515, DOI: 10.11646/zootaxa.5091.4.1, http://zenodo.org/record/586382
Dinoderus (Dinoderus) piceolus Lesne 1933
No full textDinoderus (Dinoderus) piceolus Lesne, 1933 Fig. 14 (A, B) Dinoderus piceolus Lesne, 1933: 259. Distribution in China. Hongkong (Borowski & Węgrzynowicz 2007). Other distribution. The species is endemic to China.Published as part of Zhang, Yi-Feng, Meng, Ling-Zeng & Beaver, Roger A., 2022, A review of the non-lyctine powder-post beetles of Yunnan (China) with a new genus and new species (Coleoptera: Bostrichidae), pp. 501-545 in Zootaxa 5091 (4) on page 515, DOI: 10.11646/zootaxa.5091.4.1, http://zenodo.org/record/586382
Dinoderus (Dinoderastes) speculifer Lesne 1895
No full textDinoderus (Dinoderastes) speculifer Lesne, 1895 Fig. 9 (A, B, C) Dinoderus speculifer Lesne 1895: 169. Distribution in China. Borowski and Węgrzynowicz (2012) recorded this species distributed in China, but not specified to the provincial area, Park et al. (2015) recorded this species distributed in Taiwan Province. Other distribution. Japan, Korea (Park et al. 2015). Host plants. Unknown.Published as part of Zhang, Yi-Feng, Meng, Ling-Zeng & Beaver, Roger A., 2022, A review of the non-lyctine powder-post beetles of Yunnan (China) with a new genus and new species (Coleoptera: Bostrichidae), pp. 501-545 in Zootaxa 5091 (4) on page 512, DOI: 10.11646/zootaxa.5091.4.1, http://zenodo.org/record/586382
Octodesmus parvulus
No full textOctodesmus parvulus (Lesne, 1897) * Fig. 33 Xylopertha parvula Lesne, 1897: 19. New records. China: Yunnan, Xishuangbanna, Mengsong, alt. 1600m, 25.IV.1958, leg. SY Wang, IOZ(E) 1034202(IZAS); Dehong, Ruili, alt. 1460m, 8.VI.1956, leg. TR Huang, IOZ(E) 1034216 (IZAS). Distribution in China. Yunnan only. Other distribution. India, Thailand. Introduced into Europe. Host plants. Unknown.Published as part of Zhang, Yi-Feng, Meng, Ling-Zeng & Beaver, Roger A., 2022, A review of the non-lyctine powder-post beetles of Yunnan (China) with a new genus and new species (Coleoptera: Bostrichidae), pp. 501-545 in Zootaxa 5091 (4) on page 533, DOI: 10.11646/zootaxa.5091.4.1, http://zenodo.org/record/586382
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