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| 1 | 浇注系统设计的新启示显示文摘采用底注式平稳充型的方案来设计浇注系统 ,把液流在内浇道的出口速度作为限制瓶颈 ,它控制金属液在整个浇注系统的流动速度。在保证铸型充满的前提下 ,内浇道的充型速度最好限制在 0 .5m/s以内。以普通灰铸铁精密铸造叶片为例 ,把传统的顶注式浇注系统和新的底注式浇注系统的充型结果进行比较。在充型过程中 ,采用X射线实时跟踪系统进行了观察 ,发现顶注式浇注系统充型紊乱 ,易造成夹杂 ,浇注的 2 6个叶片中 3处出现裂纹 ,3 0处出现夹杂缺陷。而采用底注式浇注系统 ,铸件充型平稳 ,没有裂纹 ,只有 3处出现夹杂缺陷 。 | 李殿中 张玉妥 李依依 J.Campbell M.H.Loretto | 2002 | 特种铸造及有色合金2002，22，4： | 37 |
| 2 | Urogenital schistosomiasis and soiltransmitted helminthiasis(STH)in Cameroon:An epidemiological update at Barombi Mbo and Barombi Kotto crater lakes assessing prospects for intensified control interventions显示文摘Background:The crater lakes of Barombi Mbo and Barombi Kotto are well-known transmission foci of schistosomiasis and soil-transmitted helminthiasis having had several important control initiatives previously.To collect contemporary epidemiological information,a cross-sectional survey was undertaken inclusive of:signs and symptoms of disease,individual treatment histories,local water,sanitation and hygiene(WASH)-related factors and malacological surveillance,with molecular characterisation of specimens.Methods:At each lake,a community cross-sectional survey was undertaken using a combination of stool and urine parasitological sampling,and interview with pro-forma questionnaires.A total of 338 children and adults participated.Material from snail and parasite species were characterised by DNA methods.Results:Egg-patent prevalence of urogenital schistosomiasis was 8.7%at Barombi Mbo(all light-intensity infections)and 40.1%at Barombi Kotto(21.2%heavy-intensity infections).Intestinal schistosomiasis was absent.At Barombi Kotto,significantly more women reported signs and symptoms associated with female genital schistosomiasis.While there had been extensive recent improvement in WASH-related infrastructure at Barombi Mbo,water contact risk scores were higher among schistosomiasis-infected participants(P<0.001)and at Barombi Kotto in general(P<0.001).Across both lakes,mean prevalence of STH was very low(6.3%)evidencing an impressive decrease of 79.0%over the last decade;neither Strongyloides stercoralis nor Ascaris lumbricoides were found.A total of 29 freshwater sampling sites were inspected for snails,13 in Barombi Mbo and 16 in Barombi Kotto;water chemistry differed significantly(P<0.0001)between lakes for both mean pH(7.9 v.9.6)and mean conductivity(64.3μS v.202.1μS)respectively.Only two Bulinus camerunensis found on the central island of Barombi Kotto were observed to shed schistosome cercariae,but schistosome DNA was later detected in Bulinus sampled from both lakes as well as in Indoplanorbis exustus,an invasive species from Asia.Conclusions:STH is currently at very low levels while urogenital schistosomiasis is of greatest concern at Barombi Kotto.This assessment highlights a unique opportunity for further study of the epidemiological dynamics at these crater lakes,to evaluate future intensified interventions both in terms of gaining and sustaining control at Barombi Kotto or in moving towards local interruption of transmission of both diseases at Barombi Mbo. | Suzy J.Campbell J.Russell Stothard Faye O’Halloran Deborah Sankey Timothy Durant Dieudonne Eloundou Ombede Gwladys Djomkam Chuinteu Bonnie LWebster Lucas Cunningham EJames LaCourse Louis-Albert Tchuem-Tchuente | 2017 | Infectious Diseases of Poverty2017，6，1： | 4 |
| 3 | Retinal regeneration requires dynamic Notch signaling显示文摘Retinal damage in the adult zebrafish induces Müller glia reprogramming to produce neuronal progenitor cells that proliferate and differentiate into retinal neurons.Notch signaling,which is a fundamental mechanism known to drive cell-cell communication,is required to maintain Müller glia in a quiescent state in the undamaged retina,and repression of Notch signaling is necessary for Müller glia to reenter the cell cycle.The dynamic regulation of Notch signaling following retinal damage also directs proliferation and neurogenesis of the Müller glia-derived progenitor cells in a robust regeneration response.In contrast,mammalian Müller glia respond to retinal damage by entering a prolonged gliotic state that leads to additional neuronal death and permanent vision loss.Understanding the dynamic regulation of Notch signaling in the zebrafish retina may aid efforts to stimulate Müller glia reprogramming for regeneration of the diseased human retina.Recent findings identified DeltaB and Notch3 as the ligand-receptor pair that serves as the principal regulators of zebrafish Müller glia quiescence.In addition,multi-omics datasets and functional studies indicate that additional Notch receptors,ligands,and target genes regulate cell proliferation and neurogenesis during the regeneration time course.Still,our understanding of Notch signaling during retinal regeneration is limited.To fully appreciate the complex regulation of Notch signaling that is required for successful retinal regeneration,investigation of additional aspects of the pathway,such as post-translational modification of the receptors,ligand endocytosis,and interactions with other fundamental pathways is needed.Here we review various modes of Notch signaling regulation in the context of the vertebrate retina to put recent research in perspective and to identify open areas of inquiry. | Leah J.Campbell Jaclyn L.Levendusky Shannon A.Steines David R.Hyde | 2022 | Neural Regeneration Research2022，17，6： | 3 |
| 4 | Towards interruption of schistosomiasis transmission in sub-Saharan Africa:developing an appropriate environmental surveillance framework to guide and to support‘end game’interventions显示文摘Schistosomiasis is a waterborne parasitic disease in sub-Saharan Africa,particularly common in rural populations living in impoverished conditions.With the scale-up of preventive chemotherapy,national campaigns will transition from morbidity-to transmission-focused interventions thus formal investigation of actual or expected declines in environmental transmission is needed as‘end game’scenarios arise.Surprisingly,there are no international or national guidelines to do so in sub-Saharan Africa.Our article therefore provides an introduction to key practicalities and pitfalls in the development of an appropriate environmental surveillance framework.In this context,we discuss how strategies need to be adapted and tailored to the local level to better guide and support future interventions through this transition.As detection of egg-patent infection in people becomes rare,careful sampling of schistosome larvae in freshwater and in aquatic snails with robust species-specific DNA assays will be required.Appropriate metrics,derived from observed prevalence(s)as compared with predetermined thresholds,could each provide a clearer insight into contamination-and exposure-related dynamics.Application could be twofold,first to certify areas currently free from schistosomiasis transmission or second to red-flag recalcitrant locations where extra effort or alternative interventions are needed. | J.Russell Stothard Suzy J.Campbell Mike Y.Osei-Atweneboana Timothy Durant Michelle C.Stanton Nana-Kwadwo Biritwum David Rollinson Dieudonne R.Eloundou Ombede Louis-Albert Tchuem-Tchuente | 2017 | Infectious Diseases of Poverty2017，6，1： | 2 |
| 5 | Impact of patch size on woody tree species richness and abundance in a tropical montane evergreen forest patches of south India显示文摘We examined the effects of forest patch size on woody tree species richness and abundance in tropical montane evergreen forest patches of the Nilgiri region,south India. We sampled woody trees(>1 cm dbh) from 21 forest patches in the upper Nilgiri hills(> 2000 m elevation) and recorded a total of 35,146 individuals of 61 species, 45 genera and 30 families. Species richness and abundance of sapling/shrubs(≥ 1 to < 10 cm dbh)increased significantly with increasing patch size, but the species richness and abundance of small, medium and larger trees(≥ 10 to < 30, ≥ 30 to < 60 and ≥ 60 cm dbh,respectively) did not. Overall, forest interior species richness and abundance increased significantly with increasing patch size but edge species richness did not. Species richness and abundance of shade-tolerant and shade-demanding tree species also increased with increasing patch size. The abundance of zoochory dispersed tree species was significantly related to increasing patch size, but those dispersed by autochory did not display any clear relationship between patch size and species richness or abundance.Our findings suggest that with increasing forest patch area,tree compositional patterns may be driven by species specific shade-tolerance adaptations and dispersal patterns.Differential responses in these traits by the plant community within the individual habitat zones of forest edge and interiors likely plays a major role in determining the inherent plant community and thus the subsequent ecological processes of forest patches, including their responses to increasing patch area. | Dharmalingam Mohandass Mason J.Campbell Priya Davidar | 2018 | Journal of Forestry Research2018，29，6： | 1 |
| 6 | Regulation A:Small Businesses Search for 'A Moderate Capital'显示文摘 | Rutheford B J.Campbell | | 0，，： | 1 |
| 7 | Some Lessons from the Yield Curve显示文摘 | J.Campbell | | 0，，09： | 1 |
| 8 | Land use conflict in Kajiado District,Kenya显示文摘 | David J.Campbell Helen Gichohi Albertm wangi | | 0，，17： | 1 |
| 9 | A hypothesis for cast iron microstructures显示文摘 | J.Campbell | | 0，，： | 1 |
| 10 | 薄壁铸件(1)显示文摘本文对合金流动性和液体流动的基本原理进行了探讨,以指明薄壁铸件生产中的主要问题,并确定尚需研究的领域。所探讨的主题包括各种不同程度的氧化物夹杂问题,引入了“新”、“旧”氧化物及其它膜层的概念。对直接导流的局限性进行了探讨(直接导流法是将金属直接竖式注入铸模的一种常用的导流方法),对U字形流道和缝隙浇口作为解决生产薄壁铸件问题的一种主要潜在方法进行了较详细的论述。讨论了限制流速的条件,表明对铸造薄壁铸件而言,不一定需要较高的铸造速度。由Weber数和Froude数估计的不稳定性是需要进一步研究的领域,必须注意避免铸件截面厚度的无目的的变化,因为这是极其有害的;强调了使用精确的铸造工具和铸模的重要性,引入了液流汇合焊合这一金属铸造中的新概念。对这一点及其它灌充困难进行了探讨,以便铸造复杂铸件;探讨了使用过滤器的益处。给出了薄壁铸件铸造技术若干最新进展的例子。 | J.Campbell 杨小永 | 1990 | 轻合金加工技术1990，18，2： | 1 |
| 11 | The End of Cheap Oil显示文摘 | Colin J.Campbell Jean H.Laherrere | | 0，，03： | 1 |
| 12 | Once Burned,Twice Cautious:Explaining the Weinberger-Powell Doctrine显示文摘 | Kenneth J.Campbell | | 0，，03： | 1 |
| 13 | Switchable Rashba anisotropy in layered hybrid organic-inorganic perovskite by hybrid improper ferroelectricity显示文摘Hybrid organic–inorganic perovskites(HOIPs)are introducing exotic directions in the photovoltaic materials landscape.The coexistence of inversion symmetry breaking and spin–orbit interactions play a key role in their optoelectronic properties.We perform a detailed study on a recently synthesized ferroelectric layered HOIP,(AMP)PbI_(4)(AMP=4-aminomethyl-piperidinium).The calculated polarization and Rashba parameters are in excellent agreement with experimental values. | Fei Wang Heng Gao Coen de Graaf Josep M.Poblet Branton J.Campbell Alessandro Stroppa | 2020 | npj Computational Materials2020，，1： | 0 |
| 14 | The effects of an experimental drought on the ecophysiology and fruiting phenology of a tropical rainforest palm显示文摘据预测,人为气候变化将季节性地增加平均温度和降雨。热带雨林物种将如何应对这种气候变化仍不确定。本研究分析了对澳大利亚昆士兰北部丹特里雨林的一种澳大利亚特有棕榈(Normambya normanbyi)进行4年降雨实验的影响,目的是了解模拟降雨减少对物种生理过程和果实物候的影响。我们考察了这种本地丰富的棕榈的果实物候和生理生态学特性,以确定该物种对干旱的生态响应。2015年5月,通过排涝实验,降低了约30%的土壤水分有效性。我们总共监测了8年(2009–2018年)的月度果实活性,包括排涝实验开始之前的4年。在最近几年的研究中,我们测量了干、湿两季幼嫩和成熟叶片的光合速率、气孔导度和碳稳定同位素等生理参数。研究结果表明,所有棕榈树的月度果实活性主要受光周期、平均太阳辐射和平均温度的驱动。然而,暴露于较低土壤水分的植株,其果实活性、光合速率和气孔导度均显著下降。我们还发现这些生理表现受到排涝实验、季节以及两者的相互作用的影响。2018年观察到排涝实验的棕榈的果实活力有所恢复,土壤浅层水分也有所增加(与前几年相比)。我们的研究结果表明,像N.normanbyi这样的棕榈树对未来的气候变化非常敏感,建议对其进行长期监测,以确定其对种群规模的影响。 | Nara O.Vogado Michael J.Liddell Susan G.W.Laurance Mason J.Campbell Alexander W.Cheesman Jayden E.Engert Ana C.Palma Françoise Y.Ishida Lucas A.Cernusak | 2020 | Journal of Plant Ecology2020，13，6： | 0 |
| 15 | Unravelling the nature of Waiparaconus, a pennatulacean (Cnidaria: Octocorallia) from the Late Mesozoic-Early Cainozoic of the Southern Hemisphere显示文摘Enigmatic calcareous conical fossils have been known from marine Paleocene-Eocene sequences of New Zea-land since the early 1870s.More recently,similar fossils have been recorded from both Late Cretaceous ma-rine sequences of Western Australia,New Caledonia and Antarctica,and possibly from the Eocene of South America.The present paper extends the record to the late Cretaceous of New Caledonia.These remains are un-like any living taxa,and have been variously interpreted as molluscs(rudistid bivalves),cirripedes(stalked bar-nacles),annelids and inorganic structures.Assignation to the Cirripedia has been refuted by Buckeridge(1983,1993),who proposed that the material would be better placed within the Cnidaria.We investigate this hypothe-sis in light of the New Caledonian material and by comparison with living gorgonians and pennatulaceans,and demonstrate that Waiparaconus is best placed within the Pennatulacea.Waiparaconus zelandicus varies in form somewhat,with 3 morphotypes defined and reinforced by geography.Comment is provided on the imperative to fit organic remains into known groups,with reflection on what may happen if taxa are left in insertae sedis. | John S.BUCKERIDGE Hamish J.CAMPBELL Pierre MAURIZOT | 2014 | Integrative Zoology2014，9，2： | 0 |
| 16 | 薄壁铸件(2)显示文摘三、简单的板铸件竖式板铸件浇注中所用的一些基本原理当然也适用于竖式圆柱铸件以及箱体铸件等的浇注。因此,本节的内容可应用于多种实际铸件的生产。 1.水平板铸件将板模水平放置进行浇注,历来受到多种理由的反对。在这种铸造方法中,液体金属流是以不规则的、无法控制的小流束遍布模腔。对容易形成表面膜的合金,表面膜就在这些流束的两侧面上形成。 | J.Campbell 杨小永 | 1990 | 轻合金加工技术1990，18，3： | 0 |
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