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Potato tubers were pre-sprouted in trays at 10 C for 28 d.The scale leaves at the base of the sprouts were marked andtubers then planted in field soil. Twenty-eight days after plantingan average of three adventitious buds were present per sproutcompared with an average of six below-ground axillary buds.Ten per cent of adventitious buds formed stolons compared withalmost 100 per cent of axillary buds. Similar responses wereseen with tubers pre-sprouted either in the light or dark. 相似文献
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Early Permian (Asselian) brachiopods from Karakorum (Pakistan) and their palaeobiogeographical significance 总被引:1,自引:0,他引:1
Abstract: Early Permian (Asselian) brachiopods collected from the Gircha Formation of western Karakorum (Pakistan) are described. They include Bandoproductus girchensis sp. nov., Kiangsiella sp. indet., Trigonotreta lyonsensis Archbold and Thomas, Trigonotreta larghii sp. nov., Spirelytha petaliformis (Pavlova), Punctospirifer afghanus Termier, Termier, de Lapparent and Marin, and ?Dielasma sp. indet. and belong to the Trigonotreta lyonsensis–Punctospirifer afghanus Assemblage Biozone, the oldest so far recovered from the Permian succession of Karakorum. The faunal succession of Karakorum records a significant biotic change from the Asselian to the Sakmarian, a shift in diversity and composition that is also recorded along most of the Gondwanan margin and Peri‐Gondwanan regions and that should be related to a major climatic change: the end of the Gondwanan glaciation. A palaeobiogeographical analysis has been performed by means of multivariate methods applying cluster and ordination analyses based on the Jaccard Coefficient and Simpson Index to a matrix consisting of the presence/absence of 23 brachiopod genera from seven geographical operational units from central Afghanistan to eastern Australia. The results suggest the occurrence of a single biotic province during the Asselian, the Indoralian Province, embracing all the faunal stations examined, as a consequence of the global cold phase related to the last pulse of the Gondwanan glaciation. 相似文献
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IAN BROCKINGTON PRABHA CHANDRA HOWARD DUBOWITZ DAVID JONES SUAAD MOUSSA JULIET NAKKU ISABEL QUADROS FERRE 《World psychiatry》2011,10(2):93-102
This guidance details the needs of children, and the qualities of parenting that meet those needs. Parental mental disorders can damage the foetus during pregnancy through the action of drugs, prescribed or abused. Pregnancy and the puerperium can exacerbate or initiate mental illness in susceptible women. After their birth, the children may suffer from the social disadvantage associated with severe mental illness. The parents (depending on the disorder, its severity and its persistence) may have intermittent or prolonged difficulties with parenting, which may sometimes result in childhood psychological disturbance or child maltreatment. This guidance considers ways of preventing, minimizing and remedying these effects. Our recommendations include: education of psychiatrists and related professions about the effect of parental mental illness on children; revision of psychiatric training to increase awareness of patients as caregivers, and to incorporate relevant assessment and intervention into their treatment and rehabilitation; the optimum use of pharmacological treatment during pregnancy; pre-birth planning when women with severe mental illness become pregnant; development of specialist services for pregnant and puerperal women, with assessment of their efficacy; community support for parenting by mothers and fathers with severe mental disorders; standards of good practice for the management of child maltreatment when parents suffer from mental illness; the importance of multi-disciplinary teamwork when helping these families, supporting their children and ensuring child protection; the development of child and adolescent mental health services worldwide. 相似文献
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CHARLES L. ROSS JAMES H. BENEDIX JR CHRISTOPHER GARCIA KALLI LAMBETH RACHEL PERRY † VANESSA SELWYN DANIEL J. HOWARD 《Biological journal of the Linnean Society. Linnean Society of London》2008,94(4):777-796
The structure of the hybrid zone between the ground crickets, Allonemobius socius and Allonemobius fasciatus , approximates an environmental mosaic based on temperature/moisture at regional spatial scales. In the present study, we show that the micro-geographic spatial structure (i.e. single fields) of this hybrid zone is governed by the same criteria. Thus, the criteria that structure this hybrid zone are scale independent, even though the agents that implement these criteria may differ at various scales (climate, latitude, and elevation at regional scales; grass height, slope aspect, and field use at micro-geographic scales). Additionally, the study demonstrates a previously unknown barrier to genetic exchange in this system that acts before conspecific sperm precedence. © 2008 The Linnean Society of London, Biological Journal of the Linnean Society , 2008, 94 , 777–796. 相似文献
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HOWARD MOSKOWITZ 《Journal of sensory studies》2002,17(3):207-213
Mapping is a popularly accepted statistical method, currently used in many applications in order to reveal and perhaps understand relations between stimuli. This paper discusses some of the shortcomings of mapping as a procedure, specifically those having to do with the 'actionability' of the data. The paper recommends that mapping be used to embed the stimuli in a geometric space, but then the coordinates of that space be used as independent variables in a model. In this way the geometrical representation does not stop at being a 'pretty picture' without further utility, but instead incorporates within it the necessary tools to allow researchers to go from any location in the space to any other location. 相似文献