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51.
范仰才  张欣  张春华 《江西科学》2011,29(6):818-821
分析了当前地方工科大学实施大学物理课程教学基本要求存在的问题,结合本校实际,在实施新《基本要求》上进行了积极的探索与实践,取得了初步成果。  相似文献   
52.
Colonial ascidians collected from wharf piles and natural substrata from Bluff Harbour and Stewart Island in the South Island of New Zealand are described in this paper. Two species, Lissoclinum violaceum sp. nov. and Didemnum marineae sp. nov. are new to science and described for the first time. The ascidian fauna in this region is a mixed assemblage of southern species, species with a New Zealand-wide distribution, and two species with trans-Tasman affinities.

www.zoobank.org/urn:lsid:zoobank.org:pub:37DC0D4B-8FB9-4F1D-A5A0-E9CAB3203447  相似文献   

53.
目的 建立输血感染戊型肝炎病毒(hepatitis E virus,HEV)兔模型,了解HEV全血输注传播的可能性,并观察感染后的指标动态.方法 以兔HEV接种4只SPF兔,经腹腔静脉窦采集抗凝血,然后立即以约10 mL/kg经耳缘静脉注射输血方式分别给予正常SPF受体兔5只,每周监测受体兔粪便和血清抗原、抗体和核酸,...  相似文献   
54.
针对红外小目标占用像素较少、背景相似性强、网络容易受到背景杂波信息干扰的问题,提出了一种基于注意力机制的红外小目标检测方法。利用注意力机制模块抑制背景杂波,增强小目标特征,并使用红外小目标检测模块实现检测任务;为了增强网络鲁棒性,通过高斯噪声与原图通道堆叠输入的数据增强方式提升网络抗杂波干扰的能力。实验表明,提出的方法在MDvsFA数据集中的性能超过了目前最新的对比算法。  相似文献   
55.
《Journal of Natural History》2012,46(13):1601-1619
Members of the bryozoan family Petraliellidae share the capacity to develop basal rhizoids, which anchor the unilaminar, semi-repent parts of the colonies above the substratum, and enable them to overgrow other, competing sessile forms. Little is known of the larval behaviour and settlement, or the early astogeny of species. Ancestrulate colonies of the Australian Tertiary lunulitiform species Smittia biincisa are referred to the genus Riscodopa, and together with Riscodopa paucipora sp. nov. are described and compared with the Recent species R. cotyla and R. parva from New Zealand, and with R. hyalina sp. nov. from New South Wales, Australia. All the Recent species are known to develop basal rhizoids, and an early astogeny similar to that of many other small, rooted bryozoans, comprising the post-metamorphosis development of a binary complex, including rhizoid and feeding elements, is inferred for Riscodopa. Observations on living Hippopetraliella magna from Queensland suggest that both the ancestrular morphology and early astogeny show a capacity for semi-repent growth, even though they do not include rhizoid development. Larvae metamorphose without direct attachment, and the ancestrula develops elongated, partially calcified supporting processes, which raise the early stages of growth above the substratum. A similar kind of ancestrula has been found in preserved specimens of Mucropetraliella ellerii.  相似文献   
56.
The Neotropical species and genera of the tribe Euderomphalini (Eulophidae: Entedoninae) are revised. Five genera are described as new: Cabeza, including six species (baeostigma (§, ¦), canaliculata (§), laticeps (¦), petiolata (§), planiscapus (§), ugaldei (§)); Itahipeus, including two species (brasilicola (§, ¦), euryceps (¦)); Monterrondo, including one species (aphelosoma (§)); Sifraneurus, including one species (strigifer (§)); Xenopomphale, including one species (sulcata (§)); all above-mentioned species are described as new. Five additional genera are included: Aleuroctonus LaSalle and Schauff, with four species, one described previously: vittatus (Dozier) (§, ¦), and three described here: latiscapus (§), marki, (§, ¦) and metallicus (§); Entedononecremnus Girault, with 14 species, two described previously: krauteri Zolnerowich and Rose (§, ¦), unicus Girault (§, ¦), and 12 described here: bennetti (§, ¦), bimaculatus (§, ¦), convexus (§, ¦), crassicornis (§, ¦), depressus (§), fulgens (§), hansoni (§, ¦), imdasus (§, ¦), parfer (§, ¦), reticulatus (§), tripar (§) and unicarinatus (§); Euderomphale Girault, with two species, one described previously: flavimedia (Howard), and one described here: sulciscapus (§, ¦); Neopomphale LaSalle and Schauff, with 20 species, two described previously: aleurothrixi (Dozier) (§, ¦), quercicola (Dozier) (§, ¦), and 18 described here: azofeifai (¦), cerrobius (¦), depilis (§), dichrous (§, ¦), erecta (¦), graciliclava (§), longicornis (¦), longipilis (§, ¦), nonaequa (§, ¦), noyesi (§), pinguicornis (§, ¦), prymna (§), rubescens (§, ¦), rubii (§), silvestris (¦), transversa (§), umbonata (§, ¦), xenipennis (§); Dasyomphale LaSalle and Schauff, including one species (chilensis LaSalle and Schauff). The genera are placed in either one of three genus-groups, one of which is newly created. The species Euderomphale quercicola Dozier is newly combined to Neopomphale. Lectotypes are designated for Entedononecremnus unicus Girault, Euderomphale quercicola Dozier and Gyrolasia flavimedia Howard. Key to genera and species are included.  相似文献   
57.
《Journal of Natural History》2012,46(9-10):509-522
Three hundred and ninety‐nine individuals representing 10 species of Litoria and five species of Nyctimystes (Hylidae), L. arfakiana, L. bibonius, L. eucnemis, L. genimaculata, L. impura, L. infrafrenata, L. modica, L. nasuta, L. thesaurensis, L. wollastoni, N. gularis, N. kubori, N. papua, N. pulcher and N. semipalmatus collected in Papua New Guinea were examined for helminths. Gravid individuals representing one species of Monogenea (Parapolystoma bulliense), one species of Digenea (Mesocoelium monas), 18 species of Nematoda (Aplectana krausi, Aplectana macintoshi, Aplectana zweifeli, Cosmocerca novaeguineae, Falcaustra papuensis, Icosiella papuensis, Maxvachonia adamsoni, Maxvachonia ewersi, Meteterakis crombiei, Moaciria moraveci, Ochoterenella papuensis, Oswaldocruzia bakeri, Parapharyngdon maplestoni, Parathelandros allisoni, Parathelandros andersoni, Physalopteroides milnensis, Rhabdias australiensis, Seuratascaris numidica) and one species of Acanthocephala (Acanthocephalus bufonis) were found. Also included were immature forms representing one species of Cestoda (as a metacestode), three species of Nematoda (Abbreviata sp., Rictulariidae gen. sp., Ascarididae gen. sp. in cysts), one species of Acanthocephala (unidentified cystacanth), and one species of Pentastomida [Raillietiella sp. (nymph)]. The mean helminth species richness for infected hosts was 1.3±0.6 SD (range one to three species). Sixty‐seven new host records and two new locality records are reported.  相似文献   
58.
《Journal of Natural History》2012,46(15-16):863-880
Adults and associated larvae of Rentonium bicolor sp. nov. are described from New Zealand (North Island) and represent the first associated larvae of the Rentoniinae. Larvae and adults were found among the fruiting bodies of Hypocrea rufa (Pers.) Fr. (Ascomycota: Hypocreaceae). The larvae are morphologically similar to a previously described and undetermined larva but differ from it by the unpaired, hook-like urogomphus, four stemmata, and the apical antennal seta subequal in length to the antenna. Potential implications for phylogeny of Cleroidea are discussed. A catalogue of the genera and species of Rentoniinae is provided, along with comments about the status of Rentonellum loebli Kolibá?.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:936541AB-1802-4C09-9032-7EF1FAAC912E  相似文献   
59.
Lernanthropus antofagastensis sp. nov., parasitic on Anisotremus scapularis, and inshore fish of Antofagasta, Chile, is described and illustrated. It resembles five other species of Lernanthropus in its dorsal plate and third leg, but can be distinguished from them by a combination of characters. L. trachuri Brian, 1903, is recorded, its male described and illustrated from specimens collected from Seriolella violacea and Trachurus murphy, taken in the same locality.  相似文献   
60.
《Journal of Natural History》2012,46(7):1049-1087
Of all of the chrysomelid subfamilies, only the larvae of the Aulacoscelinae remain undescribed. The adults and first instar larva of Aulacoscelis appendiculata sp. n., from Panama are described, as well as the eggs. Larval characters, eggs, and oviposition behaviour are used to relatethe Aulacoscelinae with other chrysomelid subfamilies, in support of what is known to date concerning adult morphology.  相似文献   
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