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1.
AW Edwards 《Genetics》2012,192(1):3-13
R. C. Punnett, the codiscoverer of linkage with W. Bateson in 1904, had the good fortune to be invited to be the first Arthur Balfour Professor of Genetics at Cambridge University, United Kingdom, in 1912 when Bateson, for whom it had been intended, declined to leave his new appointment as first Director of the John Innes Horticultural Institute. We here celebrate the centenary of the first professorship dedicated to genetics, outlining Punnett's career and his scientific contributions, with special reference to the discovery of "partial coupling" in the sweet pea (later "linkage") and to the diagram known as Punnett's square. His seeming reluctance as coauthor with Bateson to promote the reduplication hypothesis to explain the statistical evidence for linkage is stressed, as is his relationship with his successor as Arthur Balfour Professor, R. A. Fisher. The background to the establishment of the Professorship is also described.  相似文献   

2.
In 1919 the Animal Breeding Research Department was established in Edinburgh. This Department, later renamed the Institute of Animal Genetics, forged an international reputation, eventually becoming the centrepiece of a cluster of new genetics research units and institutions in Edinburgh after the Second World War. Yet despite its significance for institutionalising animal genetics research in the UK, the origins and development of the Department have not received as much scholarly attention as its importance warrants. This paper sheds new light on Edinburgh’s place in early British genetics by drawing upon recently catalogued archival sources including the papers of James Cossar Ewart, Regius Professor of Natural History at the University of Edinburgh between 1882 and 1927. Although presently a marginal figure in genetics historiography, Ewart established two sites for experimental animal breeding work between 1895 and 1911 and played a central role in the founding of Britain’s first genetics lectureship, also in 1911. These early efforts helped to secure government funding in 1913. However, a combination of the First World War, bureaucratic problems and Ewart’s personal ambitions delayed the creation of the Department and the appointment of its director by another six years. This paper charts the institutionalisation of animal breeding and genetics research in Edinburgh within the wider contexts of British genetics and agriculture in the early twentieth century.  相似文献   

3.
测定用菜豆和丝瓜饲养的美洲斑潜蝇Liriomyza sativae Blanchard蛹暴露于用正己烷稀释的番茄或南瓜叶片挥发性抽提物(TLE或PLE)72h后,羽化雌成虫在Y形嗅觉仪中对TLE或PLE的定向率、平均反应时间以及对正己烷的定向率和平均反应时间,比较幼虫寄主经历和寄主气味对美洲斑潜蝇成虫嗅觉记忆的影响。结果表明,蛹期使用非嗜食寄主植物气味处理,能增加美洲斑潜蝇羽化雌成虫对非嗜食寄主气味的定向;幼虫期的寄主经历对处理后的成虫嗅觉定向也产生影响,饲喂丝瓜的美洲斑潜蝇蛹期处理后,羽化雌成虫显著偏向选择处理气味而非正己烷,饲喂菜豆的美洲斑潜蝇对南瓜的气味也表现出同样的特点,但对番茄的气味则相反,即使处理后对番茄气味的选择比率增加,仍然偏向选择正己烷。  相似文献   

4.
The nineteenth-century British botanist, Joseph Dalton Hooker,was one of the people whose career became a model for that of the modern,professional scientist.However,he preferred to refer to himself as a philosophical botanist, rather than a professional. This paper explores the reasons for this choice,and analyses Hooker's imperial approach to plant classification, the consequences of which are still with us.  相似文献   

5.
Sir Joseph Dalton Hooker was born in Halesworth, Suffolk in 1917. The second son of Sir William Jackson Hooker, Joseph Hooker would, throughout the course of his life, become one of the most famous and lauded scientists of his day. At its pinnacle, Joseph Hooker's career would see him hold the post of Director of the Royal Botanic Gardens, Kew for 20 years (1865–1885), and be the first botanist after Joseph Banks to be elected President of the Royal Society between 1873 and 1878. His archives and letters, which are described here, are held in the Library, Art and Archives at Kew.  相似文献   

6.
长期以来,对高山三尖杉(Cephalotaxus alpina(Li) L.K.Fu)分类地位的争议缺少可靠证据。本文从居群采样的水平上比较了高山三尖杉和三尖杉(Cephalotaxus fortunei Hooker)的叶片和种子形态特征,两者除种子的长宽比率无显著差异外,种子长度,宽度,厚度,长厚比率,宽厚比率以及叶片长度和宽度均差异极显著。此外,通过散点图分析表明两者的种子宽厚比和叶片宽度的变异是间断而稳定的,这一特征能将高山三尖杉和三尖杉明显地区分,结果支持将高山三尖杉作为种的等级较为合适,不赞成将高山三尖杉作为三尖杉的变种或亚种的分类处理。同时,对标本和原始文献的研究认为胡秀英(1964)发表的园桃杉(Cephalotaxus fortunei Hooker var. globosa S.Y.Hu)和高山三尖杉应是同一分类群。  相似文献   

7.
The first floristic work on the Galápagos Islands was published by J. D. Hooker in 1847. It was based mainly on the Beagle collections of Charles Darwin, but those of James McRae, John Scouler. Hugh Cuming, David Douglas, Thomas Edmonston, Abel Du Petit-Thouars and John Goodridge were also used, though those of Archibald Menzies, the first botanist to visit the archipelago, were not. The visits of these naturalists and their collections are discussed. Darwin's field notes on Galápagos plants, hitherto unpublished, are given, and most of the species identified. In the taxonomic portion of the paper, each taxon included by Hooker is discussed, the nomenclaturally or-taxonomically correct name is indicated, specimens examined by Hooker are enumerated, and additional specimens presumably seen but not cited by him are given. Hooker wrote before our present type concept had evolved, and consequently 51 of his 114 new names needed to be typified, as did four others based on Darwin Galápagos collections. In addition, examination of these specimens revealed one species not yet reported from the archipelago ( Galium canescens ), one new island record ( Chamaesyce hirta on James Island), and one deletion from the flora ( Malachra capitala )  相似文献   

8.
Abstract The induction of olfactory preferences by larval and early adult experience for odour from wheat or maize grain was examined for the granary weevil Sitophilus granarius L. in a static four-chamber olfactometer. Weevils were reared on either wheat or maize grain and received different early adult experience. It turned out that weevils that were reared in wheat and isolated as pupae from the kernels preferred wheat odour in the olfactometer when they emerged without any odour or in the presence of maize odour. Weevils that emerged in the presence of wheat odour preferred both wheat and maize odour. When weevils emerged normally as adults from the wheat kernel in which they developed, maize odour was avoided. In contrast, for weevils that were reared in maize no preferences were found in most experiments. Only weevils that emerged in the presence of wheat odour preferred the maize odour over the controls. These results demonstrate that host-selection behaviour in S. granarius weevil is shaped by experience according to the Hopkins host-selection principle or the chemical legacy hypothesis and the neo-Hopkins principle.  相似文献   

9.
Joseph Hooker first learned that Charles Darwin believed in the transmutation of species in 1844. For the next 14 years, Hooker remained a “nonconsenter” to Darwin’s views, resolving to keep the question of species origin “subservient to Botany instead of Botany to it, as must be the true relation”. Hooker placed particular emphasis on the need for any theory of species origin to support the broad taxonomic delimitation of species, a highly contentious issue. His always provisional support for special creation waned during the 1850s as he lost faith in its expediency for coordinating the study of plant geography, systematics and physiology. In 1858, Hooker embraced Darwin’s “considerable revolution in natural history,” but only after Darwin had carefully molded his transmutationism to meet Hooker’s exacting specifications.  相似文献   

10.
A kinematic analysis of the knee function is important for the evaluation of total knee arthroplasties (TKA). We used the coordination and variability of rising from a chair as functional knee parameters. Twelve knee patients were measured prior to surgery (=pre-TKA group) and one year after surgery (=post-TKA group). A group of 15 healthy, age-matched subjects was selected as control group. The WOMAC questionnaire, frequently used by orthopaedic surgeons, was administered prior to the test. The test consisted of 10 times rising from a low chair and 10 times from a high chair. Knee and hip angles and angular velocities were measured with electrogoniometers. The relative phase (=MRP) between hip and knee was a measure for the coordination of rising and the standard deviation of the relative phase of the 10 trials (=SRP) was a measure for the variability. The coordination and variability of rising of the TKA patients were compared to the control group, and the relationship with the WOMAC questionnaire was calculated. The coordination of rising from a high chair and the variability of rising from both chair heights were significantly different for the pre-TKA group compared to the control group (p<0.05). The post-TKA group showed no significant differences with the control group, which indicates a functional recovery after TKA implantation. The functional parameters correlated adequately with the subjective WOMAC questionnaire. This study showed that our method is an objective measure of functionality and it will be worthwhile to use it as an additional evaluation tool.  相似文献   

11.
Overnight chair restraint results in a dramatic increase in serum amyloid A protein (apoSAA) of nonhuman primate high density lipoprotein (HDL). To determine whether apoSAA induction resulted in a displacement of indigenous HDL protein or a change in the subfraction distribution of HDL, we analyzed the characteristics of HDL subfractions in eight vervet monkeys before and 24 hr after apoSAA induction. Blood was taken from each animal before and after chair restraint to induce apoSAA. HDL was isolated from the plasma by ultracentrifugation and agarose column chromatography. The isolated HDL was subfractionated by density gradient centrifugation and five resulting subfractions were analyzed for protein and lipid content. With apoSAA induction there was a significant increase in d less than 1.09 g/ml protein, phospholipid, and free and esterified cholesterol which resulted in a 44% increase in the total mass of this subfraction. Concomitantly, there was a significant decrease in d 1.10-1.11 g/ml protein, total cholesterol, and cholesteryl ester, which resulted in a 16% decrease in the total mass of the subfraction. The response of the d 1.10-1.11 and d greater than 1.12 g/ml subfraction protein, cholesterol, and phospholipid concentrations to chair restraint for individual animals was directly proportional to their plasma HDL concentrations. Although there was a change in the HDL subfraction concentrations after chair restraint, there was no change in the lipid composition of the HDL subfractions nor in the total amount of HDL protein. However, the apoSAA/A-I ratio was significantly increased with induction while the apoA-II + C's/A-I ratio remained unchanged. The apoSAA/A-I ratio progressively increased with the density of the HDL subfraction. The protein composition of the d greater than 1.12 g/ml subfraction was changed from an average of three apoA-I and two apoA-II (or C's) molecules per particle to an average of two apoA-I, one apoA-II (or C's), and three or four apoSAA molecules per particle after chair restraint. Thus, apoSAA was predominantly associated with the denser HDL subfractions even though the lighter HDL subfractions were the most responsive in terms of changes in concentration. These data suggest that chair restraint of nonhuman primates induces apoSAA which displaces apoA-I and apoA-II or C's from HDL without altering the overall lipid and protein composition of the particle. In addition, chair restraint alters the concentration of HDL subfractions in ways that may be independent of apoSAA induction.  相似文献   

12.
In 1931‐2, Henry Balfour, the Curator of the Pitt Rivers Museum at the University of Oxford, decided to create a systematic archive out of the collection of ethnographic photographs that he had actively collected for the Museum over many years. The result was a series of thematically arranged boxes intended to form a cross‐cultural research resource. The archival groupings formed pose a series of questions about the legacy of cultural comparativism in the twentieth century as it emerged from Victorian socio‐cultural evolutionism and typological classification, and how it has been rethought within a shifting intellectual rationale for the ethnographic museum in more recent times. The article both examines the specific genealogy and broader historical contexts for the comparative method within the Pitt Rivers Museum itself, as well placing it within the context of other archival projects of the 1930s. Through a comparison with the photograph collection of the Warburg Institute, which was reorganized along similar lines at a similar period, we understand Balfour's project not simply as a final efflorescence of Victorian museum anthropology, but also as part of a wider universalizing archival movement of the inter‐war period. The article seeks to understand why the archive series Balfour created was not continued by subsequent curators at the Museum, arguing that the postcolonial period brought with it significant challenges to the identity and role of ethnographic museums, and especially the intellectual underpinnings of cultural comparativism, and that these challenges were engaged with by reinterpreting arrangement by type within a general humanist agenda.

Résumé

En 1931‐1932, Henry Balfour, conservateur du Pitt Rivers Museum à l'Université d'Oxford, décida de créer des archives systématiques à partir de la collection de photographies ethnographiques qu'il avait recueillie au fil des années pour son musée. Le résultat tient dans une série de boîtes classées par thèmes, censées constituer une ressource pour les recherches interculturelles. Les regroupements ainsi archivés posent une série de questions sur l'héritage du comparativisme culturel au XXème siècle, tel qu'il est né de l'évolutionnisme socioculturel victorien et de la classification typologique, et la manière dont il a été repensé plus récemment, avec l'évolution du cadre de justification intellectuelle du musée ethnographique. L'article examine spécifiquement la généalogie de la méthode comparative et, plus largement, son contexte historique, au Pitt Rivers Museum lui‐même et dans le contexte d'autres projets d'archivage des années 1930. Une comparaison avec la collection photographique de l'Institut Warburg, réorganisé vers la même époque et selon des principes similaires, fait apparaître le projet de Balfour non plus simplement comme une simple efflorescence de l'anthropologie muséographique victorienne, mais aussi comme un élément d'un mouvement d'archivage plus large, universalisant, pendant l'entre‐deux‐guerres. L'article cherche à comprendre pourquoi la série d'archives créée par Balfour n'a pas été continuée par les conservateurs suivants du musée. Selon l'auteur, la période postcoloniale a fortement remis en question l'identité et le rôle des musées ethnographiques et notamment les fondements intellectuels du comparativisme culturel, et la réponse à cette remise en question a pris la forme d'une réinterprétation de la classification typologique au sein d'un système global humaniste.  相似文献   

13.
Introduction and aims The first contact a clinical service has with a patient is often an appointment letter and thus it is important that this letter is written in a way which is accessible. One concern is to write in language which is easily able to be read by the majority of recipients. A simple initial way to assess this is by using measures of readability of text.Methods We applied measures to examine the readability of appointment and administrative letters sent to young people by clinicians in the Young People's Department at the Royal Cornhill Hospital in Aberdeen.Results Many letters were unlikely to be understood by our youngest patients. We revised the letters to meet an agreed standard of readability, and agreed their routine use within the team. All letters were significantly improved on standard measures of readability and were preferred by patients.Conclusions The methods used are feasible, easily available and may be helpful to clinicians working in other specialties to improve the level of readability of written communication. This will help patients and families in their first contact with any clinical service.  相似文献   

14.
Loomba A  Loomba K  Bains R  Bains VK 《Gerodontology》2012,29(2):e1190-e1194
doi: 10.1111/j.1741‐2358.2011.00576.x Management of a dentigerous cyst in a medically compromised geriatric patient: a case report Background: Because of the increasing number of older persons seeking dental care, the growing trend towards a longer dental appointment and increased administration of drugs in dentistry, the possibility of occurrence of medical emergencies in dental offices has shown an upward trend. Objective: This case report discusses enucleation of a central dentigerous cyst in a 72‐year old male on long‐term low dose aspirin therapy. Material and methods: Surgical removal of impacted tooth with total enucleation of cystic lesion was performed in the dental chair under 2% lidocaine with 1:200,000 adrenaline, 3 days after aspirin cessation. After complete debridement of the surgical site, the wound was sutured and a gauge saturated with 10% tranexamic acid was placed on surgical site for 30 minutes. Result: No post‐operative complications or bleeding was seen on subsequent appointment and healing was normal. Conclusion: A geriatric and medically compromised patient demands special care and attention; and the decision to cease aspirin before surgery or not is of critical importance.  相似文献   

15.
Following the recommendations of an investigating committee headed by John Lindley, responsibility for the maintenance of the neglected royal estates at Kew was assumed by the State in 1840. Sir William Jackson Hooker, who had long coveted the post, was appointed the first Director. Under his able supervision, the Royal Botanic Gardens rapidly expanded and were imaginatively landscaped, new greenhouses, including the famous Palm House, were erected, and three museums of economic botany were opened. Hooker's own extensive collections formed the nucleus of the Herbarium and Library which made Kew an important centre of taxonomic research. Joseph Dalton Hooker who succeeded his father as Director, although continuing to improve and develop the Gardens, concentrated his efforts on essentially scientific activities particularly in the fields of systematics and phytogeography. To a great extent the international reputation enjoyed by the Gardens today is due to the vision, determination and energy of the two Hookers.  相似文献   

16.
All four diasteromeric 16,17-diols in the 3-methoxy-13alpha-estra-1,3,5(10)-triene series have been synthesized. The trans-diols 1 and 2 can be obtained by hydroborating the 17-enol acetate 6 (61%, ratio 27:73, preferred alpha attack). OsO(4) dihydroxylation of the olefin 7 yielded the cis-diols 3 and 4 (ratio 13:87). The dihydroxylation proceeds with preference for beta attack caused by a C-ring twist-boat form of 7. The conformations of the diols 2 and 4, the 17-benzyl-17-hydroxy compounds 9 and 10 (obtained by Grignard reaction), and the 16alpha-bromo-17beta-hydroxy compound 8 were determined by X-ray analysis and by 1H NMR spectroscopy in solution. Some compounds, in spite of a 17beta-hydroxy group, had a conformation with a ring C chair form (4, 8, 9) caused by intermolecular interaction in the solid state. The rest of the compounds studied here (2, 10) possessed a conformation with a ring C twist-boat form, which has been also found for all 17beta-substituted compounds in solution. The preferred conformation of the D-ring with 17beta-substituents seems to be the 16beta-envelope form or near this form, but the existence of the 16alpha-envelope form (inversion of the ring D) for some compounds showed great variance in the conformation of ring D, which is substituent dependent.  相似文献   

17.
B Mount 《CMAJ》1995,153(9):1340-1342
An expert in palliative care has taken exception to a recent CMAJ article dealing with euthanasia. That column praised a magazine article in which a son explained why he and his family had helped their mother commit suicide in the face of a terminal illness. Dr. Balfour Mount says the article was misleading and offers no credible solutions to the issues surrounding palliative care.  相似文献   

18.
Germination, penetration and sporulation of Cercospora henningsii (Allesch.) on cassava leaves were studied by scanning electron microscopy. Conidia started to germinate 9 h postinoculation producing one to two germ tubes. The germ tubes entered the leaf tissue through the abaxial surface by direct penetration of the epidermis without forming appressoria. The cassava leaf is characterized by its papillose epidermis on the abaxial surface. The penetrations occurred at smooth areas of the leaf epidermis between the papillae. The germ tubes did not enter stomata even when they passed over stomatal openings. Leaf spots started to appear 9 days after the inoculation (dpi), and the emergence of conidia occurred 14 dpi. The symptoms appeared first on the abaxial leaf surface, followed 2 days later on the adaxial. Conidia emerged in clusters through ruptured epidermis on both sides of the leaves. Conidia emerged also through the epidermal papillae and the leaf veins. Even though small groups of conidia emerged through stomata also, emergence through stomata appeared to be random rather than a preferred route. Each conidium was born on a short conidiophore with a swollen base.  相似文献   

19.
The kinetics of nitrate inhibition of carbon tetrachloride (CT) transformation were examined using a denitrifying consortium. Comparison of data from fed-batch experiments to the model reported by Hooker et al. indicate that the inhibition constant ranges between 3.2 and 21 mg/L, with an average of 8.8 mg/L. This range is much lower than the previously reported value of 169 mg/L. Simulations using the corrected parameter accurately reflect this new data and the data reported by Hooker et al. In contrast, the earlier reported coefficient value does not reflect the data reported in this work. (c) 1995 John Wiley & Sons, Inc.  相似文献   

20.
The purpose of this paper was to examine the effect of chair restraint on plasma enzyme values in the rhesus monkey. Six monkeys were restrained to the monkey chair for eight hours. Creatine phosphokinase (CK) value increased significantly three hours after the onset of restraint and LDH value did eight hours after the onset of restraint. The increase in CK, GOT and GPT values continued for 1 or 2 days after the release from restraint. On the other hand, these plasma enzyme values in non-restraint monkeys showed almost no changes. These results indicate that it is necessary to establish a proper method for the adjustment to chair restraint in the rhesus monkey.  相似文献   

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