Studies in the Alismataceae. III. Floral anatomy of Ranalisma humile

1973 ◽  
Vol 51 (5) ◽  
pp. 891-897 ◽  
Author(s):  
W. A. Charlton ◽  
A. Ahmed

The flower of Ranalisma humile is comparable in morphology to those of other alismads. The vascular anatomy is noteworthy. Flowers of R. humile are provided with a major (central) vascular system supplying androecial and gynoecial vasculature and a variable amount of the sepal and petal vasculature, and a minor (peripheral) system which supplies the rest of the perianth vasculature. There is very little anastomosis between the two systems. It is suggested that the variability of perianth vascular supply reflects variability in timing of differentiation events. The occurrence of an almost independent peripheral vascular system is probably of significance in a consideration of the relationship of Ranalisma humile to other alismads.

Author(s):  
Елизавета Александровна Молчанова ◽  
Петр Вячеславович Лужнов

В работе приведены понятия жесткости, эластичности и тонуса сосудов, а также же их взаимосвязь с общим состоянием сосудистой стенки. Описан индекс, объединяющий влияние вышеперечисленных факторов на состояние сосудистой системы и дающий представление о возрасте сосудов пациента, а также показана связь этого индекса с возрастом человека. Представлен обзор способов определения возраста сосудов с помощью контурного анализа пульсовой волны. Среди предложенных способов был выделен подход на основе контурного анализа сигнала пульсовой волны, а также ее второй производной. В данном исследовании проводилась разработка алгоритма расчета показателя возраста сосудов (VA), базирующаяся на анализе сигнала и его второй производной. При этом особое внимание уделялось физической интерпретации параметров, входящих в состав расчетной формулы. С помощью представленного алгоритма в группе из трех испытуемых был определен сосудистый возраст. Из анализа полученных результатов было выявлено влияние физиологических факторов на значение возраста сосудов. Предложены методики, позволяющие исключить влияние этих факторов на значения показателя VA и тем самым получить более точные результаты. Также представлены стратегии дальнейшего развития исследований в этом направлении In The paper presents the concepts of rigidity, elasticity and tone of blood vessels, as well as their relationship with the general state of the vascular wall. An index is described that combines the influence of the above factors on the state of the vascular system and gives an idea of the age of the patient's vessels, and also shows the relationship of this index with the age of a person. An overview of the methods for determining the age of blood vessels using the contour analysis of the pulse wave is presented. Among the proposed methods, an approach based on the contour analysis of the pulse wave signal, as well as its second derivative, was singled out. In this study, an algorithm was developed for calculating the indicator of vascular age (VA), based on the analysis of the signal and its second derivative. In this case, special attention was paid to the physical interpretation of the parameters included in the calculation formula. Using the presented algorithm, vascular age was determined in a group of three subjects. From the analysis of the results obtained, the influence of physiological factors on the value of the age of the vessels was revealed. Methods are proposed that allow to exclude the influence of these factors on the values of the VA indicator and thereby obtain more accurate results. Also presented are strategies for the further development of research in this direction


2019 ◽  
pp. 774-792
Author(s):  
Keith F. Snider

This chapter explores the relationship of U.S. defense management to public administration. It argues that public administration, as a field of study, plays a minor role in defense acquisition, because acquisition has unique characteristics that separate it from the mainstream of the field. The tenuous connections between acquisition and public administration have led to an issue of academic legitimacy in that the discipline has failed to respond to the needs of acquisition professionals. The chapter then presents a discussion and illustration of philosophical pragmatism as a potential contribution of administrative theory to acquisition practice, and it concludes with thoughts on the potential for acquisition to adopt pragmatism as a guiding way for thought and practice.


2009 ◽  
Vol 42 (01) ◽  
pp. 018-021
Author(s):  
R. Chitra

ABSTRACTThe aim of this study was to demonstrate the relationship between the deep fibular nerve and the dorsalis pedis artery to provide useful anatomical knowledge for safe surgical approaches in plastic surgery. The dissection of 30 cadaver lower limbs was undertaken to describe the relationship of the deep fibular nerve to the dorsalis pedis artery in the anterior tarsal tunnel and on the dorsum of the foot. The anterior tarsal tunnel is a flattened space between the inferior extensor retinaculum and the fascia overlying the talus and navicular. The deep fibular nerve and its branches pass longitudinally through this fibro-osseous tunnel, deep to the tendons of the extensor hallucis longus and extensor digitorum longus. Four distinct relationships of the deep fibular nerve to the dorsalis pedis artery were determined. The dorsalis pedis neurovascular island flap contains both the dorsalis pedis artery and the deep fibular nerve. Because the design of a neurovascular free flap requires detailed knowledge of the nerve and vascular supply, the data presented here are intended to help surgeons during surgical approaches to the foot and ankle.


1998 ◽  
Vol 1 (6) ◽  
pp. 522-527 ◽  
Author(s):  
E.J. Lazda

Two cases of fetal endocardial fibroelastosis are reported in the larger of growth-discordant monozygotic twins. The growth discordance in these two cases is regarded as a manifestation of twin-twin transfusion syndrome, but other causes are considered and the difficulties posed by the observed placental vascular anatomy are discussed. The literature on endocardial fibroelastosis in multiple pregnancy is briefly reviewed, and the relationship of endocardial fibroelastosis to the cardiovascular compromise seen in twin-twin transfusion syndrome is considered.


2007 ◽  
Vol 4 (6) ◽  
pp. 4443-4458 ◽  
Author(s):  
T. Leefmann ◽  
J. Bauermeister ◽  
A. Kronz ◽  
V. Liebetrau ◽  
J. Reitner ◽  
...  

Abstract. Methane-related carbonates from Hydrate Ridge typically show several macroscopically distinguishable phases, namely whitish aragonite, lucent aragonite, and gray micrite. The relationship of these phases to particular microorganisms or biogeochemical processes is as yet unclear. We used a miniaturized biomarker technique on mg samples, combined with factor analysis and subsequent electron microprobe analysis, to study lipid biomarkers and chemical compositions of the individual phases. This allows us to identify particular mechanisms involved in the formation of the different carbonate precipitates. Our combined analysis of biomarkers and petrographic traits shows that most of the lipids related to the anaerobic oxidation of methane (>90% by weight) are concentrated within only a minor compartment (~20% by volume) of the Hydrate Ridge carbonates (whitish aragonite). The patterns indicate that the whitish aragonite represents fossilized biofilms of methanotrophic consortia, whereas the precipitation of the lucent aragonite does not seem to be directly controlled by microorganisms. The gray micrite shows a partly Mg-calcitic mineralogy, higher pyrite contents, and a much higher proportion of allochthonous biomarkers. The formation of these precipitates is interpreted to reflect periodic methane-rich fluid pulses that disrupted the sediments and promoted the growth of the respective methanotrophic consortia along fluid pathways.


Palaeobotany ◽  
2018 ◽  
Vol 9 ◽  
pp. 54-75
Author(s):  
L. B. Golovneva ◽  
A. A. Zolina

Cercidiphyllaceae-like leaves and fruits from the Lower Cretaceous deposits of Northeastern Asia were restudied. In the result one species of Jenkinsella fruits and five species of Trochodendroides leaves were recognized, including Trochodendroides potomacensis (Ward) Bell, T. buorensis Golovneva, T. sittensis Golovneva, sp. nov., T. vachrameeviana (Iljinskaja) Golovneva, comb. nov., and T. denticulata (Budantsev et Kiritchkova) Golovneva, comb. nov. Two new combinations and one new species are published. These plants had very small leaves and probably were shrubs. Fruits of Nyssidium orientale Samylina from the Barremian-Aptian Starosuchan Formation (Primorye, Russia) have no follicular characters as Jenkinsella fruits. Their affinity, not only to Cercidiphyllum-like plants, but to angiosperms in general, is doubtful. Leaves and fruits of Cercidiphyllum sujfunense Krassilov from the lower-middle Albian Galenki Formation (Primorye) also can not be assigned to Cercidiphyllaceae. Leaves have pinnate, brochidodromous venation and are comparable with those of Asiatifolium elegans Sun, Guo et Zheng, which were recorded from the Frentsevka Formation of the Partizansk coal basin, Primorye, Russia, and from the Chengzihe Formation, Northeastern China. Thus, the first reliable records of the genus Trochodendroides appear in the early-middle Albian. The relationship of these leaves with Cercidiphyllaceae is confirmed by finds of associated fruits Jenkinsella filatovii and by significant diversity of Trochendroides in the Late Albian-Cenomanian. In the early-middle Albian the genus Trochendroides was a minor component of the conifer-dominated Mesophytic floras. These fossils reflect the early radiation of Cercidiphyllaceae and indicate that this family began to diversify more then 30 million years before the Tertiary. Investigation of the early-middle Albian Cercidiphyllaceae provides important new data for our understanding of the early evolution of eudicots.


1970 ◽  
pp. 157
Author(s):  
Sirkku Pihlman

When I read Elina Salminen’s doctoral thesis I found myself many times thinking, why she finds the relationship of the museums and the private collections called museums so very problematic. In cases examined by her, several museum professionals considered these private collections to be of a minor significance from the standpoint of the institutional museums. On the other hand, interviewed private collectors whose collections have been accepted in a professional museum collection did not deal the professional principles of e.g. the permanence of collections. This seems not to be a severe confrontation anyway. 


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