scholarly journals Gems from Private Collections. III.–Phacops Caudatus; from the Dudley Limestone

The Geologist ◽  
1859 ◽  
Vol 2 (4) ◽  
pp. 160-161
Author(s):  
J. Tennant

The beautiful specimen of Phacops caudatus, which we figure in Plate V., has long been in the private collection of Professor Tennant. It is from the Upper Silurian limestone of Dudley, and would be a perfect example but for the exception only of its having the segments of the body somewhat bent inwards, and slightly distorted from their natural positions by pressure. The lateral edges and their segments are unfortunately obscured by being embedded in the matrix, so that they cannot be accurately delineated.This characteristic species of Trilobite was first noticed by Brunnich, in 1781, under the name of Trilobus caudatus. It was subsequently termed Asaphus caudatus by Brongniart, Dalman, Dr. Buckland, and other writers. Burmeister, however, in his valuable work on the “Organization of Trilobites,” called it Phacops caudatus, which generic determination modern palæontologists have followed.

2020 ◽  
Vol 47 (2) ◽  
pp. 392-401
Author(s):  
T. R. Birkhead ◽  
G. Axon ◽  
J. R. Middleton

Most of the approximately 75 known eggs of the extinct great auk ( Pinguinus impennis) are in public museums, with a few in private collections. A small number of these eggs has sustained damage, either at the time of collection or subsequently, and two of these eggs are known to have been repaired. The two eggs suffered rather different types of damage and were subsequently restored using different techniques. The first, known as Bourman Labrey's egg, sustained extensive damage sometime prior to the 1840s, when the shell was broken into numerous pieces. This egg was repaired by William Yarrell in the 1840s, and when it was restored again in 2018, it was discovered that Yarrell's restoration had involved the use of an elaborate cardboard armature. This egg is currently in a private collection. The second egg, known as the Scarborough egg, bequeathed to the Scarborough Museum in 1877, was damaged (by unknown causes) and repaired, probably by the then curator at Scarborough, W. J. Clarke, in 1906. This egg was damaged when one or more pieces were broken adjacent to the blowhole at the narrow end (where there was some pre-existing damage). The media reports at the time exaggerated the extent of the damage, suggesting that the egg was broken almost in two. Possible reasons for this exaggeration are discussed. Recent examination using a black light and ultraviolet (UV) revealed that the eggshell had once borne the words, “a Penguin's Egg”, that were subsequently removed by scraping.


Human Arenas ◽  
2021 ◽  
Author(s):  
Ramiro Tau ◽  
Laure Kloetzer ◽  
Simon Henein

AbstractIn this paper, we attempt to show some consequences of bringing the body back into higher education, through the use of performing arts in the curricular context of scientific programs. We start by arguing that dominant traditions in higher education reproduced the mind-body dualism that shaped the social matrix of meanings on knowledge transmission. We highlight the limits of the modern disembodied and decontextualized reason and suggest that, considering the students’ and teachers’ bodies as non-relevant aspects, or even obstacles, leads to the invisibilization of fundamental aspects involved in teaching and learning processes. We thus conducted a study, from a socio-cultural perspective, in which we analyse the emerging matrix of meanings given to the body and bodily engagement by students, through a systematic qualitative analysis of 47 personal diaries. We structured the results and the discussion around five interpretative axes: (1) the production of diaries enables historicization, while the richness of bodily experience expands the boundaries of diaries into non-textual modalities; (2) curricular context modulates the emergent meanings of the body; (3) physical and symbolic spaces guide the matrix of bodily meanings; (4) the bodily dimension of the courses facilitates the emergence of an emotional dimension to get in touch with others and to register one's own emotional experiences; and (5) the body functions as a condition for biographical continuity. These axes are discussed under the light of the general process of consciousness-raising and resignification of the situated body in the educational practice.


Author(s):  
А.Н. Баженов ◽  
П.А. Затылкин

Публикация посвящена применению методов вычислительной геометрии, интервального анализа и линейного программирования к задачам физики управляемого термоядерного синтеза. Рассмотрены геометрические аспекты проблемы, получены проекции светимостей различных объемов сферического токамака на плоскость матричного детектора, изучены изображения предполагаемых макроскопических структур и микроскопических включений. Для набора модельных распределений светимости объема токамака поставлена задача восстановления сигнала. Решение получено с использованием задач линейного программирования. The problems of reconstruction of plasma luminosity are important for physics and technology of power plants-tokamaks. The Globus-M research tokamak obtained a large amount of data using a matrix detector in pinhole camera geometry. From the mathematical point of view, finding the luminosity for different regions of the plasma volume according to the matrix detector is an inverse problem related to the field of integral geometry. An essential feature of the particular task is the use of a single fixed camera with a small viewing angle. In this regard, application of methods of harmonic analysis of data is not enough. The paper investigates the geometric aspects of the problem. In the general view, a threedimensional object is projected onto a two-dimensional plane through a diaphragm. Under the assumption of azimuthal symmetry, there is a central projection of the luminosity of the body of rotation onto a flat matrix detector. The initial information for the calculation is the plasma boundary obtained from magnetic sensors. There is no reliable information about the internal structure of the plasma, so its division into regions of the equal luminosity is not unambiguous. The paper presents an algorithm for finding the projections of the luminosity of plasma volumes on the plane of the matrix detector. A set of model direct problems for the construction of algorithms for their recognition according to the detector data was investigated. Images of supposed macroscopic structures and microscopic inclusions were obtained. The methodological basis of the work is the use of interval analysis methods for solving geometric and algebraic problems. This approach allows obtaining qualitative and quantitative results that takes into account the uncertainty of the input data with the minimum amount of computational costs. Algebraic solvability is investigated in the interval formulation using response functionality. Solutions for a set of test problems are obtained, which demonstrate the availability of successful reconstruction for real data. An important result of the study is an information about the presence of uncertainties in geometric data and related calculations by obtaining results about the luminosity of the plasma by solving linear programming problems.


2000 ◽  
Author(s):  
E. Sélard ◽  
A. Shirazi-Adl ◽  
J. P. G. Urban

Abstract The intervertebral disc consists of a water-rich extra-cellular matrix which is synthesized and maintained by its cells. The disc is the largest avascular tissue in the body with its cells lying as much as 8mm away from the blood supply. Nutrients, essential for maintaining cellular viability, diffuse through the matrix from blood supply under a concentration gradient arising from cellular demand. The oxygen concentration gradients in the intervertebral disc are investigated to examine the effects of exchange area and disc thickness on oxygen flux in the disc. The concentration gradients are computed using the two-dimensional Poisson’s equation and measured values for oxygen consumption rate and oxygen diffusion.


Parasitology ◽  
1993 ◽  
Vol 107 (4) ◽  
pp. 449-457 ◽  
Author(s):  
M. E. Selkirk ◽  
W. F. Gregory ◽  
R. E. Jenkins ◽  
R. M. Maizels

SUMMARYThe expression of a protein complex designated gp15/400, previously identified via extrinsic iodination of adultBrugia malayi, was examined by labelling all stages found in the mammalian host and immunoprecipitation with a specific antibody raised to a recombinant protein. In this way, gp15/400 could be detected in L3, L4, adult worms and microfilariae recovered from jirds and labelled with Bolton–Hunter reagent. Metabolic labelling indicated that gp15/400 was released into culture medium when adult worms were maintainedin vitro, but at a rate slower than that of gp29, the major soluble cuticular glycoprotein. Immuno-electron microscopy showed that the protein complex was broadly distributed in different tissues, although it was not detectable in the cuticle of adult worms. Dense labelling was observed in the matrix of the basal laminae bordering the hypodermis, somatic musculature and oesophagus, and lower but significant labelling was seen in the cells overlying these extracellular matrices. Hybridization of genomic DNA with a cDNA probe encoding gp15/400 indicated that homologous genes were present inDirofilaria immitisandAcanthocheilonema viteae. The failure to detect related genes in non-filarial nematodes was presumed to be due to divergence beyond the practical limits of detection by nucleic acid probes, as antibody reagents showed that the protein cross-reacted immunologically with ABA-1, a major protein allergen from the body fluid ofAscaris.


2019 ◽  
Vol 11 ◽  
Author(s):  
Krzysztof Haptaś

Libraries and Private Book Collections in the Town of Mielec at the Time of the Partition of Poland: An Outline Libraries and private book collections in Mielec at the time of the partition of Poland have not been sufficiently traced and researched so far. The best known are the library of the Mielec secondary school (gimnazjum) and the private collection of the Count Oborski family. General remarks, in the scope of a few sentences at best, pertain to other school libraries and private collections. Numerous collections, some that are known by the name, such as the library of the Trinitarian convent, and some that we are not aware of, still await researchers. Currently, all old books (published before 1945) that are kept in the town of Mielec need to be cataloged in order to start the actual efforts to chart the history of the local libraries and private book collections.


The Geologist ◽  
1860 ◽  
Vol 3 (02) ◽  
pp. 55-62
Author(s):  
George C. Roberts

Coral-Hunting in the debris of a Wenlock-shale quarry ranks high— to my thinking—amongst the pleasures of geology. And, indeed, has no insignificant place among its wonders. For to any one not conversant with zoophytic life, it is hard to believe that the rugged corals that lie strewn about the quarry, once held sensitive masses of life—that from every pore tiny arms waved to and fro in the water to entangle the lesser creatures they lived on; and that the animal— that slight thread of jelly-like substance, filling each tube, was at once a limb of the body and an independent creature, contributing, while attached, to the general support, and being able, if severed from the mass, to lead a separate existence and be itself the parent of others. The Wenlock series of the Upper Silurians have been rightly regarded as the metropolis of its zoophytic life, for both in variety and number, corals culminated in the seas of that age. Of these species, “so far removed from existing ones as to be quite unknown in modern seas, all with rare exceptions, dying out at the close of the Palæozoic epoch.” I will essay a familiar sketch.


2000 ◽  
Vol 18 (5) ◽  
pp. 1135-1135 ◽  
Author(s):  
Amy R. Nelson ◽  
Barbara Fingleton ◽  
Mace L. Rothenberg ◽  
Lynn M. Matrisian

ABSTRACT: Tumor progression is a complex, multistage process by which a normal cell undergoes genetic changes that result in phenotypic alterations and the acquisition of the ability to spread and colonize distant sites in the body. Although many factors regulate malignant tumor growth and spread, interactions between a tumor and its surrounding microenvironment result in the production of important protein products that are crucial to each step of tumor progression. The matrix metalloproteinases (MMPs) are a family of degradative enzymes with clear links to malignancy. These enzymes are associated with tumor cell invasion of the basement membrane and stroma, blood vessel penetration, and metastasis. They have more recently been implicated in primary and metastatic tumor growth and angiogenesis, and they may even have a role in tumor promotion. This review outlines our current understanding of the MMP family, including the association of particular MMPs with malignant phenotypes and the role of MMPs in specific steps of the metastatic cascade. As scientific understanding of the MMPs has advanced, therapeutic strategies that capitalize on blocking the enzymes have rapidly developed. The preclinical and clinical evolution of the synthetic MMP inhibitors (MMPIs) is also examined, with the discussion encompassing important methodologic issues associated with determining clinical efficacy of MMPIs and other novel therapeutic agents.


2018 ◽  
Vol 57 (2) ◽  
pp. 175-182
Author(s):  
E.G. Zemtsova ◽  
A.N. Ponomareva ◽  
A.Y. Arbenin ◽  
V.M. Smirnov

Abstract The important stage of the development of smart material for the target drug delivery is the construction of the magnetic part of this material, including mesoporous silica and magnetic nanoparticles (Fe3O4or Fe0). Such a systemwill allow carry outmagnetic decapsulation (excretion) of drug from smart material using the magnetic field of a given value in the right place of the body. The paper considers the features of synthesis mesoporous silica MCM-41 with various pore diameter (33-51 Å) and synthesis of superparamagnetic nanoparticles of magnetite or metallic iron in the pores of mesoporous silica. The dependence of magnetic properties of nanocomposites MCM-41/Fe0 and MCM-41/Fe3O4 from the pore diameters of MCM-41 templates is studied. It was found that the matrix has a decisive influence on the content of iron or magnetite nanoparticles. The saturation magnetization of the material increases with increasing pore size of the mesoporous matrix. Nanocomposites MCM-41/Fe0 and MCM-41/Fe3O4 exhibit superparamagnetism, that allows them to be used as a magnetic material for targeted drug delivery.


2019 ◽  
Vol 51 (06) ◽  
pp. 389-395 ◽  
Author(s):  
Gregorio Caimi ◽  
Baldassare Canino ◽  
Maria Montana ◽  
Caterina Urso ◽  
Vincenzo Calandrino ◽  
...  

AbstractThe association between obesity and cardiovascular diseases has a multifactorial pathogenesis, including the synthesis of inflammatory molecules, the increase in oxidative stress and the dysregulation of the matrix metalloprotease (MMP) concentration and activity. In a group of adults with obesity, divided in 2 subgroups according to the body mass index (BMI), we examined lipid peroxidation, expressed as thiobarbituric acid-reactive substances (TBARS), protein oxidation, expressed as protein carbonyl groups (PCs), plasma gelatinases (MMP-2 and MMP-9), and their tissue inhibitors (TIMP-1 and TIMP-2). In the whole group, as well as in the 2 subgroups (with BMI 30–35 or BMI>35) of obese subjects, we observed an increase in TBARS, PCs, MMP-2, and MMP-9, and also TIMP-1 and TIMP-2 in comparison with the control group. A positive correlation between TBARS and PCs emerged in obese subjects and persisted after dividing obese subjects according to BMI. The correlation between MMP-2 and TIMP-2 was not statistically significant, while a significant correlation was present between MMP-9 and TIMP-1. The correlations between the markers of oxidative stress (TBARS and PCs) and those of the MMP/TIMP profile indicated a more marked influence of protein oxidation on MMPs and TIMPs in comparison with TBARS. The innovative aspect of our study was the simultaneous evaluation of oxidative stress markers and MMP/TIMP profile in adult obese subjects. We observed significant alterations and correlations that may negatively influence the clinical course of the disease.


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