305,361 research outputs found
Variability of the v. cava caudalis and its tributaries in some laboratory animals. II. The laboratory rat (Rattus norvegicus v. alba).
No full textDuplication of the v. renalis was found in 11 of the regions examined (18.3%), when it was more frequent on the right side. A v. capsularis was found in 35 regions (58.3%), usually as a single vein. There were 1-3 vv. suprarenales (but mostly two; on the right they usually joined the v. cava caudalis and on the left the v. renalis sinistra). A v. spermatica was present on the right side in every case, but on the left side in 11 cases only; in one case it was duplicated. In the rat, the v. spermatica was rather thin; if absent, it was replaced by the v. deferentialis. In nine cases (60.0%) the v. uterina cranialis dextra opened into the v. cava caudalis, while in 12 cases (80.0%) the left vein opened into the v. renalis sinistra. A v. uterina media, draining blood from the caudal third of the cornu uteri, was found in only five cases (16.7%). The v. uterina caudalis drained blood from the corpus and cervix uteri. The v. ovarica was a constant finding; it was mostly joined by the v. lumbalis--and on the left side by the v. phrenica sinistra. In males, the vv. lumbales occurred mostly as a pair of veins lying just below the vv. renales. In females, they were present on both sides. As a rule, the v. iliolumbalis occurred as a single vein on both sides. The v. cava caudalis originated at the level of the transition between the lumbar and the sacral spine, usually at the confluence of the two vv. iliacae communes, which in 14 cases (46.7%) were joined by the v. sacralis mediana. Duplication of the v. cava caudalis was found in only one case (a female). Comparison of the morphology of the v. cava caudalis and its tributaries in the rat and the guinea pig showed more slight differences between the two species
Some comment on new "collagen bodies" described in human auricular skin.
No full textThe authors evaluate thè new finding of "collagcn bodies" described by Heine in thè human auricular
skin. The used morphologlcal melhods without ultrastructural examination are not sufflcient lo
prove thè existence of this structure. In addition, thè comparison of thè new "collagen bodies" with
Rufflni sensore is quite iiiadcquate. Finally thè autonomous fibers "innervating" thè bodies are not
proved and represent only a presumption. It is thè authors' opinion that it is not necessary to look for
new sensory structures in thè human auricular skin, as thè existing sensore in this region are able to
explain thè transfer of impulses to different levels of thè CN
Variability of the v. cava caudalis and its tributaries in some laboratory animals. I. The guinea pig (Cavia aperea f. porcellus).
No full textThe authors studied variability of the v. caudalis and its tributaries in 30 guinea pigs (Cavia aperea f. porcellus--15 males and 15 females) after injecting the relevant venous system with blue-dyed latex. Since the largest lobe of the guinea pig's liver (the lobus sinister) is situated on the left, the right kidney lies further cranially than the left one. In males, as a rule, the right v. renalis opens into the v. cava caudalis further cranially than the left one. The number of vv. renales showed no sex-related differences, although in 17 regions (i.e. in 29%) there was more than one. The increase most often concerned the v. renalis dextra (the ratio in relation to the left vein was 15:2). The tributaries of the vv. renales are the v. spermatica or v. uterina cranialis a v. lumbalis and a v. or vv. suprarenales. There are usually two tributaries, (the commonest of which is the v. spermatica or v. uterina cranialis) on both the right and the left side, though somewhat more frequently on the left (23:19). Blood is drained from the surface or capsule of the kidney relatively often (in 75% of the cases) by the capsularis, which is the most frequent tributary of the v. spermatica or v. uterina cranialis of the corresponding side. Vv. suprarenales (1-4) are a constant finding on both sides. In males they open more often into the v. cava caudalis and in both sexes they also open into the v. renalis and v. lumbalis. The v. spermatica dextra opened into the v. renalis dextra in 10 cases and the v. spermatica sinistra into the v. renalis sinistra in 12 cases. The v. uterina cranialis dextra was a tributary of the v. renalis dextra in eight cases and the v. uterina cranialis sinistra joined the v. renalis sinistra in 13 cases. Drainage into the v. renalis can thus be regarded as the norm in both sexes and on both sides. The v. uterina caudalis leads from the corpus and cervix uteri and joins the v. uterina cranialis. It has a regular incidence and caudally it is most often a tributary of the v. iliaca communis. The v. ovarica is a constant tributary of the v. uterina cranialis; it is usually joined by several vv. lumbales or v. v. capsulares.(ABSTRACT TRUNCATED AT 400 WORDS
Origin of the v. portae and variability of its tributaries in laboratory animals. V. The golden (Syrian) hamster (Mesocricetus auratus).
No full textThe authors studied the origin and variability of the v. portae in 30 adult golden hamsters (Mesocricetus auratus) of both sexes after injecting blue-dyed latex into their portal bed. In 16 cases (53.3%) the v. portae was formed from three tributaries and in 11 cases (36.7%) from four. The v. mesenterica cranialis was the only constant tributary, the v. lienalis was a tributary in 28 cases (93.3%) and the other most frequent tributaries were the v. gastroduodenalis and the v. pancreaticoduodenalis cranialis. In one case there was an anastomosis between the v. portae and the v. cava caudalis. In 25 cases (83.3%) the v. gastrica sinistra joined the v. lienalis, in four (13.3%) it was an independent tributary of the v. portae and in one case (3.3%) it was duplicated. A v. cardiaca was found in 25 cases (83.3%), when it was most frequently a tributary of the v. gastroepiploica sinistra and v. gastrica sinistra. In one case only it was an independent tributary of the v. portae. A v. pylorica was observed in 29 cases (96.7%), usually (in 17 cases--56.7%) as a tributary of the v. gastroepiploica dextra; in three cases it was an independent tributary of the v. portae (10.0%). A v. pancreaticoduodenalis cranialis was formed in 28 cases (93.3%). In 12 cases (40.0%), together with the v. gastroepiploica dextra, it was a tributary of the v. gastroduodenalis and in eight cases (26.7%) it was an independent tributary of the v. portae. In two cases (6.7%) the two vv. pancreaticoduodenales united to form v. pancreaticoduodenalis communis. In three cases (10.0%) this vein was duplicated and in one case it was triplicated. A v. gastroepiploica dextra was found in 26 cases (86.7%) and a v. gastroepiploica sinistra in 22 (73.3%). Both veins occurred simultaneously in 19 cases (63.3%). In no case, however, was there a continuous venous arc along the curvatura major ventriculi. A v. lienalis was present in 28 cases (93.3%). It was absent in two cases (6.7%), in which it was replaced by inter-organ anastomoses with the stomach and pancreas. In 19 cases (63.3%), the v. gastroepiploica sinistra and v. gastrica sinistra were both its main tributaries and in five cases (16.7%) its main tributary was the v. gastrica sinistra. In one case the v. lienalis was duplicated. Inter-organ anastomoses were formed in all 30 cases (100%). They occurred between the spleen and the stomach in 27 cases (90%) and between the spleen and the pancreas in 28 cases (93.3%).(ABSTRACT TRUNCATED AT 400 WORDS
Stochastic Precedence and Minima Among Dependent Variables
No full textThe notion of stochastic precedence between two random variables emerges as a relevant concept in several fields of applied probability. When one consider a vector of random variables X1,..,Xn, this notion has a preeminent role in the analysis of minima of the type minj∈AXj for A ⊂{1,...n}. In such an analysis, however, several apparently controversial aspects can arise (among which phenomena of “non-transitivity”). Here we concentrate attention on vectors of non-negative random variables with absolutely continuous joint distributions, in which a case the set of the multivariate conditional hazard rate (m.c.h.r.) functions can be employed as a convenient method to describe different aspects of stochastic dependence. In terms of the m.c.h.r. functions, we first obtain convenient formulas for the probability distributions of the variables minj∈AXj and for the probability of events {Xi=minj∈AXj}. Then we detail several aspects of the notion of stochastic precedence. On these bases, we explain some controversial behavior of such variables and give sufficient conditions under which paradoxical aspects can be excluded. On the purpose of stimulating active interest of readers, we present several comments and pertinent examples
El cielo del justo observador. Constantino Malinovsky y el giro copernicano de la estética peruana
No full textConstantino Malinovsky y Harlamoff, ingeniero, arqueólogo y esteta peruano, fue un inmigrante de la Rusia Blanca nacionalizado peruano que realizó importantes contribuciones al estudio, la divulgación y la interpretación del arte precolombino en el Perú. Lo que se transparenta a lo largo de la lectura de sus obras es una mirada honesta, justa y sincera del arte peruano precolombino —que nosotros denominaremos el giro copernicano en la estética peruana—, ajeno a todo esencialismo y artificialismo propio de los arqueólogos y estudiosos del arte contemporáneos a Malinovsky. Nuestro trabajo procederá en tres secciones: 1) Definir —contrario a Kant y demás autores— lo que llamaremos como giro copernicano trazado more geometrico y distinguirlo del giro trascendental o malogrado, trazado more ethico. 2) Revisar las adversas circunstancias en las cuales Malinovsky consigue su naturalización como peruano, a la par que desarrolla su teoría “cromática” respecto del arte peruano precolombino según campos visuales no antes explorados arqueológicamente y manejando la luz de una forma particular en sus análisis. Argumentaremos por qué la propuesta de Malinovsky es más bien una de corte estética filosófica more geometrico que las contemporáneas desde la antropología, arqueología e historia more ethico. 3) Finalmente, aplicaremos el nuevo concepto de giro copernicano a la propuesta estética de Malinovsky y brindaremos las conclusiones relativas a por qué su obra conjunta es un giro copernicano en la estética peruana
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
The heaven of the just observer. Constantino Malinovsky and the Copernican turn of Peruvian aesthetics
No full textConstantino Malinovsky y Harlamoff, ingeniero, arqueólogo y esteta peruano, fue un inmigrante de la Rusia Blanca nacionalizado peruano que realizó importantes contribuciones al estudio, la divulgación y la interpretación del arte precolombino en el Perú. Lo que se transparenta a lo largo de la lectura de sus obras es una mirada honesta, justa y sincera del arte peruano precolombino —que nosotros denominaremos el giro copernicano en la estética peruana—, ajeno a todo esencialismo y artificialismo propio de los arqueólogos y estudiosos del arte contemporáneos a Malinovsky. Nuestro trabajo procederá en tres secciones: 1) Definir —contrario a Kant y demás autores— lo que llamaremos como giro copernicano trazado more geometrico y distinguirlo del giro trascendental o malogrado, trazado more ethico. 2) Revisar las adversas circunstancias en las cuales Malinovsky consigue su naturalización como peruano, a la par que desarrolla su teoría “cromática” respecto del arte peruano precolombino según campos visuales no antes explorados arqueológicamente y manejando la luz de una forma particular en sus análisis. Argumentaremos por qué la propuesta de Malinovsky es más bien una de corte estética filosófica more geometrico que las contemporáneas desde la antropología, arqueología e historia more ethico. 3) Finalmente, aplicaremos el nuevo concepto de giro copernicano a la propuesta estética de Malinovsky y brindaremos las conclusiones relativas a por qué su obra conjunta es un giro copernicano en la estética peruana.Constantino Malinovsky y Harlamoff, Peruvian engineer, archaeologist and aesthete, was an immigrant from White Russia who became a Peruvian citizen and made important contributions to the study, divulgation and interpretation of Pre-Columbian art in Peru. What emerges through the reading of his works is an honest, fair and sincere look at Peruvian pre-Columbian art —which we will call the Copernican turn in Peruvian aesthetics— free from all essentialism and artificialism typical of archaeologists and art scholars contemporary to Malinovsky. Our paper will proceed in three sections. 1) To define —contrary to Kant and other authors— what we will call the Copernican turn, tracing more geometrico, and to distinguish it from the transcendental or failed turn, tracing more ethico. 2) We will review the adverse circumstances in which Malinovsky achieves his naturalization as a Peruvian at the same time as he develops his “chromatic” theory regarding pre-Columbian Peruvian art according to visual fields not previously explored archaeologically. We will argue why Malinovsky’s proposal is more of a philosophical aesthetic more geometrico than the contemporary ones from anthropology, archaeology and history more ethico. 3) Finally, we will apply the new concept of Copernican turn to Malinovsky’s aesthetic proposal and provide conclusions regarding why their joint work is a Copernican turn in Peruvian aesthetics
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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