scholarly journals The paraleucobryoid Campylopus complex (Leucobryaceae) in South American páramos

2019 ◽  
Vol 68 (1-2) ◽  
pp. 95-103
Author(s):  
Bruce Allen ◽  
William R. Buck
Keyword(s):  
Small Group ◽  
Cross Section ◽  
South American

Abstract The paraleucobryoid Campylopus complex consists of a small group of Andean species distinguished by a leaf cross section identical to that of Paraleucobryum. The complex differs from Paraleucobryum only in having cygneous rather than erect setae and capsule stomata absent rather than present. Here we treat four species, only two of which have previously been recognized in Campylopus. They are C. albidovirens Herzog, C. pittieri R.S.Williams, C. densifolius (Thér.) B.H.Allen & W.R.Buck, comb. nov. and C. ochyriorum B.H.Allen & W.R.Buck, sp. nov. A key is given to the four species; the two nomenclatural novelties are described in detail and illustrated.

scholarly journals Lymnaea rupestris sp. n. from Southern Brazil (Pulmonata: Lymnaeidae)

1982 ◽  
Vol 77 (4) ◽  
pp. 437-443 ◽  
Author(s):  
W. Lobato Paraense
Keyword(s):  
Cross Section ◽  
British Museum ◽  
South American ◽  
University Of Michigan ◽  
Close Proximity ◽  
Nidamental Gland ◽  
Basal Half ◽  
Wet Rocks ◽  
Deep Suture ◽  
Bodies Of Water

A new species of South American lymnaeid snail, Lymnaea rupestris, is described. So far it has been found only in its type-locality, Nova TeuTõnia, a village in the municipality of Seara (27° 07' S, 52° 17' W), state of Santa Catarina, Brazil. It is distinguishable, by characteristics of the shell and internal organs, from the other two lymnaeid species known to occur in the area, Lymnaea columella and L. viatrix. Its shell has 4 markedly shouldered whorls, deep suture, ovoid or rounded aperture occupying about half the length of the shell, and reaches about 6 mm in length in adults; in columella and viatrix the shell has 4-5 rounded whorls, shallow suture, and reaches over 10 mm in adults; the aperture is ovoid, occupying about half the length of the shell in viatrix, about two thirds in columella. Anatomically it is readily separated from L. columella by the shape of the ureter, straight in rupestris, with a double flexure in columella. Comparison with L. viatrix shows the following main differences: distalmost portion of the oviduct with a low, caplike lateral swelling in rupestris, with a well-developed pouch in viatrix; uterus bent abruptly caudalward in rupestris, only slightly curved rightward in viatrix; basal half of the spermathecal duct hidden by the prostate in rupestris, wholly visible or nearly so in viatrix; spermiduct sinuous and uniformly wide in rupestris, straight and gradually narrowing in viatrix; prostate more than half as long and nearly as wide as the nidamental gland, and with a slit-like lumen in cross-section in rupestris, less than half as long as and much narrower than the nidamental gland, and with an inward fold in cross-section in viatrix; penial sheath about as long and as wide as the prepuce in rupesris, shorter and narrower than the prepuce in viatrix. An important ecological characteristic of L. rupestris is its habitat on wet rocks most often outside bodies of water, although in close proximity to them. Specimens were deposited in the following malacological collections: Instituto OswaldoCruz, Rio de Janeiro; Academy of Natural Sciences, Philadelphia; Museum of Zoology, University of Michigan; and British Museum (Natural History).

Gretchen Is: On Your Facebook Profile, Analyzing the Sociolinguistics of Your Status Message

2018 ◽  
Author(s):  
Gretchen McCulloch
Keyword(s):  
Social Interaction ◽  
Small Group ◽  
Cross Section ◽  
Real Life ◽  
Good Luck ◽  
Basic Information ◽  
Social Success ◽  
Expression Of Emotion ◽  
Current Location

Some Facebook status messages get dozens of comments and "likes", while others are not interacted with at all. But is this social success just good luck, or are there certain features that can allow us to predict whether a status will be popular or not? This presentation examines a cross‐section of authentic Facebook status messages in an attempt to figure out what makes a status socially successful. Three types of status message are identified: the narcissistic status, the informative status, and the shared‐reference status. The narcissistic status is the stereotypical expression of emotion or mundane activity, where the audience is less important, and consequently less engaged, than the author. The informative status provides basic information about the user's current location or activity, which can allow him or her to be more easily contacted by friends, but does not tend to inspire much conversation. However, it is the shared‐reference status, which refers to an experience that the author shares with a relatively small group of friends, that inspires the greatest levels of dialogue in the form of comments and "likes." Further details to be discussed include the varieties of shared‐reference status and the relation of Facebook statuses to external perception of them and to real‐life rules of social interaction.

Redescription of Parotocinclus bahiensis (Miranda-Ribeiro, 1918) (Pisces, Ostariophysi, Loricariidae)

Zootaxa ◽  
2009 ◽  
Vol 2143 (1) ◽  
pp. 59-67 ◽  
Author(s):  
HERALDO A. BRITSKI ◽  
JULIO CESAR GARAVELLO
Keyword(s):  
Small Group ◽  
Cross Section ◽  
Color Pattern ◽  
Caudal Peduncle ◽  
Caudal Fin ◽  
Lateral Plates

Microlepidogaster bahiensis Miranda-Ribeiro (1918), assigned to Parotocinclus Eigenmann & Eigenmann, 1889, by Garavello (1977), was described in a short and uninformative way which does not allow for its distinction from other species of Parotocinclus; besides, the two syntypes of the species are regarded as lost. For these reasons a neotype is herein designated and a detailed description of the species is presented based on topotypes. The species is characterized by the combination of the following features: scapular bridge almost completely exposed ventrally, arrector fossae, when present, small or very reduced; abdomen covered by 5–7 wide lateral plates on each side and very small platelets in between, leaving abundant naked areas surrounding them; a small group of larger plates in front of anus; caudal peduncle ellipsoid in cross section; total plates in median series 21–23; longitudinal series with 23–26 plates; 18–29 teeth on premaxillary and 12–24 on dentary; it can also be distinguished by its characteristic caudal-fin color pattern. Features that allow us to assign the species to Parotocinclus and a hypothesis about its relationships with other species of the genus are also presented.

Institut de Recherches et d'Applications des Méthodes de Développement, Paris

1965 ◽  
Vol 3 (4) ◽  
pp. 608-611
Author(s):  
Henryane De Chaponay
Keyword(s):  
Small Group ◽  
South American ◽  
Colonial Rule ◽  
Non Profit ◽  
The People ◽  
Swiss Law ◽  
Development Methods

The Institute for Research and Experiment in Development Methods is an international, private, non-profit-making association under Swiss law. Its headquarters are in Geneva and its management in Paris (Rue Réaumur). The constitution requires that all its activities shall be carried out without political, religious, or racial distinction.I.R.A.M. was born along with the newly independent countries, to answer the historical need for research and action to ensure the participation of the people in development programmes. It is based on the notion of‘animation’, which arose resulting from a meeting between African and South American leaders and a small group of Europeans who had been actively involved in the struggle for independence in many countries under colonial rule before 1956.

Many roads from pasture to plate: a commodity chain approach to China’s beef trade, 1732–1931

2019 ◽  
Vol 14 (1) ◽  
pp. 22-43
Author(s):  
Thomas David DuBois
Keyword(s):  
North America ◽  
Cross Section ◽  
Foreign Investment ◽  
Export Trade ◽  
South American ◽  
Commodity Chain ◽  
Beef Industry ◽  
Meat Packing ◽  
Refrigerated Transport ◽  
Meat Packing Industry

AbstractThe advent of refrigerated transport made fresh beef a global commodity, linking South American and Australian producers to hungry consumers in Europe and North America. With vast supplies of cattle, and growing markets in Japan, Russia, and beyond, China was the last great frontier of this global transformation. Rather than a single export trade, China’s beef industry was a complex and multidirectional network of producers, processors, and consumers, its many production chains each facing distinct commercial, logistic, and political challenges. This article examines three such chains, the Qing-era caravan trade that drove live sheep and cattle to Beijing, the Harbin meat-packing industry that grew up around the Russian China Eastern Railway, and Japanese-dominated export of beef from Qingdao. A cross-section of these issues shows how the industry as a whole adapted to the new pressures and opportunities of globalization, as well as those presented by technology, foreign investment, imperialism, and war.

XUV Absorption Spectra of Carbon Ions

1988 ◽  
Vol 102 ◽  
pp. 71-73
Author(s):  
E. Jannitti ◽  
P. Nicolosi ◽  
G. Tondello
Keyword(s):  
Absorption Spectra ◽  
Cross Section ◽  
Theoretical Calculations ◽  
Photoionization Cross Section ◽  
Carbon Ions

AbstractThe photoabsorption spectra of the carbon ions have been obtained by using two laser-produced plasmas. The photoionization cross-section of the CV has been absolutely measured and the value at threshold, σ=(4.7±0.5) × 10−19cm2, as well as its behaviour at higher energies agrees quite well with the theoretical calculations.

Elastic Scattering in Electron Microscopy

1973 ◽  
Vol 31 ◽  
pp. 252-253
Author(s):  
J. Langmore ◽  
M. Isaacson ◽  
J. Wall ◽  
A. V. Crewe
Keyword(s):  
Electron Microscopy ◽  
Elastic Scattering ◽  
Cross Section ◽  
Quantum Noise ◽  
Dark Field ◽  
Elastic Cross Section ◽  
Biological Molecules ◽  
Dark Field Microscopy ◽  
Field Systems ◽  
Effects Of Radiation

High resolution dark field microscopy is becoming an important tool for the investigation of unstained and specifically stained biological molecules. Of primary consideration to the microscopist is the interpretation of image Intensities and the effects of radiation damage to the specimen. Ignoring inelastic scattering, the image intensity is directly related to the collected elastic scattering cross section, σɳ, which is the product of the total elastic cross section, σ and the eficiency of the microscope system at imaging these electrons, η. The number of potentially bond damaging events resulting from the beam exposure required to reduce the effect of quantum noise in the image to a given level is proportional to 1/η. We wish to compare η in three dark field systems.

A New Approach to the Demonstration of Oxidase-Localization Using Tannic Acid Or Catechin

1973 ◽  
Vol 31 ◽  
pp. 698-699
Author(s):  
V. Mizuhira ◽  
Y. Futaesaku
Keyword(s):  
Cross Section ◽  
Tannic Acid ◽  
Elastic Fiber ◽  
The Other ◽  
New Approach ◽  
Tissue Block ◽  
Active Reaction ◽  
The Cross

Previously we reported that tannic acid is a very effective fixative for proteins including polypeptides. Especially, in the cross section of microtubules, thirteen submits in A-tubule and eleven in B-tubule could be observed very clearly. An elastic fiber could be demonstrated very clearly, as an electron opaque, homogeneous fiber. However, tannic acid did not penetrate into the deep portion of the tissue-block. So we tried Catechin. This shows almost the same chemical natures as that of proteins, as tannic acid. Moreover, we thought that catechin should have two active-reaction sites, one is phenol,and the other is catechole. Catechole site should react with osmium, to make Os- black. Phenol-site should react with peroxidase existing perhydroxide.

Electron Irradiation Effects in Polyoxymethylene Crystals Grown Inside Trioxane Crystals

1971 ◽  
Vol 29 ◽  
pp. 78-79
Author(s):  
J. P. Colson ◽  
D. H. Reneker
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Detailed Examination ◽  
The Other ◽  
Electron Micrograph ◽  
Irradiation Effects ◽  
Threefold Axis ◽  
Typical Sample ◽  
Polymer Crystals ◽  
Chain Axis

Polyoxymethylene (POM) crystals grow inside trioxane crystals which have been irradiated and heated to a temperature slightly below their melting point. Figure 1 shows a low magnification electron micrograph of a group of such POM crystals. Detailed examination at higher magnification showed that three distinct types of POM crystals grew in a typical sample. The three types of POM crystals were distinguished by the direction that the polymer chain axis in each crystal made with respect to the threefold axis of the trioxane crystal. These polyoxymethylene crystals were described previously.At low magnifications the three types of polymer crystals appeared as slender rods. One type had a hexagonal cross section and the other two types had rectangular cross sections, that is, they were ribbonlike.

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