scholarly journals Tardigrades and Their Emergence as Model Organisms

2022 ◽  
Author(s):  
Bob Goldstein
Keyword(s):  
The Other ◽  
Model Organisms ◽  
Comparative Biology ◽  
Extreme Conditions ◽  
Laboratory Studies ◽  
C Elegans ◽  
The Past ◽  
Research Findings ◽  
Invertebrate Model ◽  
The Rich

Experimentally tractable organisms like C. elegans, Drosophila, zebrafish, and mouse are popular models for addressing diverse questions in biology. In 1997, two of the most valuable invertebrate model organisms to date – C. elegans and Drosophila – were found to be much more closely related to each other than expected. C. elegans and Drosophila belong to the nematodes and arthropods respectively, and these two phyla and six other phyla make up a clade of molting animals referred to as the Ecdysozoa. The other ecdysozoan phyla could be valuable models for comparative biology, taking advantage of the rich and continual sources of research findings as well as tools from both C. elegans and Drosophila. But when the Ecdysozoa was first recognized, few tools were available for laboratory studies in any of these six other ecdysozoan phyla. In 1999 I began an effort to develop tools for studying one such phylum, the tardigrades. Here, I describe how the tardigrade species Hypsibius exemplaris and tardigrades more generally have emerged over the past two decades as valuable new models for answering diverse questions. To date, these questions have included how animal body plans evolve and how biological materials can survive some remarkably extreme conditions.

HISTORICAL HERITAGE AS A MEANS OF MORAL TRAINING OF SOCIAL TEACHERS

2021 ◽  
Vol 66 (2) ◽  
pp. 180-187
Author(s):  
І.R. Halitova ◽  
◽  
N.O. Atemkulova ◽  
G.K. Shirinbayeva ◽  
◽  
...  
Keyword(s):  
The Other ◽  
Human Society ◽  
The Past ◽  
Moral Training ◽  
Literary Heritage ◽  
The Rich ◽  
Historical Heritage ◽  
Social Side ◽  
The One ◽  
Social Pedagogue

The introduction of socio-pedagogical ideas into the historical and literary heritage enriches the content of training, makes it possible to enrich their practical skills through familiarity with historical experience, on the one hand, on the other hand, it enriches the inner world of social teachers as specialists, connecting the feeling and consciousness, thereby creating conditions for successful effective activities. In human society, various types of contradictions have always appeared at any time, but at the same time , methods and ways to eliminate them have been invented. Unfortunately, we have recently become interested in foreign technologies of training and education, their ideas, and have lost sight of the rich experience of the past, which includes methods and methods of social education of children and youth. The problem is that it is necessary to identify them and use them in practice. The activity of a social pedagogue , in particular, is associated with rehabilitation, socialization and other types of work among children, youth and adults. The history of social pedagogy spiritually enriches future specialists on the one hand, and on the other, helps to accumulate the experience of the past in order to use them in solving modern problems. Literary and historical materials concerning the social side of the life of the Kazakh people in this regard is important and essential.

Mechanisms of Axonal Degeneration and Regeneration

2017 ◽  
pp. 574-592 ◽  
Author(s):  
Jiaxing Li ◽  
Catherine A. Collins
Keyword(s):  
Axonal Degeneration ◽  
Morphological Changes ◽  
Axonal Injury ◽  
Model Organisms ◽  
C Elegans ◽  
The Face ◽  
Invertebrate Model ◽  
Critical Components ◽  
Injury Models ◽  
Shed Light

In the face of acute or chronic axonal damage, neurons and their axons undergo a number of molecular, cellular, and morphological changes. These changes facilitate two types of responses, axonal degeneration and regeneration, both of which are remarkably conserved in both vertebrates and invertebrates. Invertebrate model organisms, including Drosophila and C. elegans, have offered a powerful platform with accessible genetic tools for manipulation and amenable nervous system for visualization. Thus far, several critical components and pathways in axonal degeneration and regeneration have been identified in invertebrate studies, including Sarm and Wallenda/DLK. This article highlights important findings in Drosophila, C. elegans, and other invertebrate injury models that have shed light upon the mechanism in axonal injury response.

scholarly journals Circuit Degeneracy Facilitates Robustness and Flexibility of Navigation Behavior in C.elegans

2018 ◽  
Author(s):  
Muneki Ikeda ◽  
Shunji Nakano ◽  
Andrew C. Giles ◽  
Wagner Steuer Costa ◽  
Alexander Gottschalk ◽  
...  
Keyword(s):  
Nervous System ◽  
Single Cell ◽  
Environmental Temperature ◽  
Neural Circuits ◽  
The Other ◽  
Cultivation Temperature ◽  
Behavioral Component ◽  
C Elegans ◽  
The Past ◽  
Animal Behaviors

AbstractAnimal behaviors are robust and flexible. To elucidate how these two conflicting features of behavior are encoded in the nervous system, we analyzed the neural circuits generating a C. elegans thermotaxis behavior, in which animals migrate toward the past cultivation temperature (Tc). We identified multiple circuits that are highly overlapping but individually regulate distinct behavioral components to achieve thermotaxis. When the regulation of a behavioral component is disrupted following single cell ablations, the other components compensate the deficit, enabling the animals to robustly migrate toward the Tc. Depending on whether the environmental temperature surrounding the animals is above or below the Tc, different circuits regulate the same behavioral components, mediating the flexible switch between migration up or down toward the Tc. These context-dependencies within the overlapping sub-circuits reveal the implementation of degeneracy in the nervous system, providing a circuit-level basis for the robustness and flexibility of behavior.

scholarly journals Why Study History

2012 ◽  
Vol 11 (3) ◽  
pp. 61
Author(s):  
Bhupendra Yadav
Keyword(s):  
20Th Century ◽  
The Other ◽  
Rear View Mirror ◽  
The Past ◽  
Other Hand ◽  
Utilitarian Value ◽  
Henry Ford ◽  
The Rich

The rich and famous have looked down upon history for most of the 20th century. In 1916, the pioneer car manufacturer, Henry Ford, declared „History is bunk‟ because it‟s an unwanted vestige of tradition. On the other hand, in 2005, Thomas Friedman, thought the past was overloaded with memories, these remembrances were the assassins of dreams and any society with more memories than dreams was destined to decay. Contrary to this, we argue here that history has four distinct uses, it is an aesthetic guide and moral teacher like biographies, it has a utilitarian value as a rear view mirror, it is a political device to legitimise nations and it is one epistemological tool to understand society.KeywHistoriography; Historical ords: History; thinking

scholarly journals Urgent Development on Contemporary Medical Fiqh in Malaysia

2015 ◽  
Vol 2 (2) ◽  
pp. 81-88
Author(s):  
Noor Naemah Abdul Rahman ◽  
Mohd Anuar Ramli ◽  
Shaikh Mohd Saifudden Shaikh Mohd Salleh ◽  
Mohammad Naqib Hamdan
Keyword(s):  
Islamic Law ◽  
Technology Development ◽  
The Other ◽  
Legal Decision ◽  
The Past ◽  
Expert Opinions ◽  
Islamic Jurisprudence ◽  
Important Study ◽  
Research Findings ◽  
Contemporary Medicine

The contemporary scientific and technology development give impacts on the development of Islamic law. The dynamic of fiqh in handling issues especially on medicine become a momentum of the synergy of the two diciplines, science and the Islamic jurisprudence of medicine. Many medical issuess are yet to require legal completions that are contemporary ijtihad based on perubatan discipline. On the other hand, ijtihad not only as exclusively unilateral, moreover inclusive multilateral approach (ijtihad jama’i) is needed on handling fiqh issues. It is because expert opinions also important in describing about those issuess. Without those opinions, Islamic law scholar could not give appropriate legal decision. However, this study will explore about the importance of development of Fiqh of Medicine based on contemporary ijtihad. These studies will explain some contemporary Medicine issuees, which is proof the requirement of contemporary ijtihad. For example on the issues of reproduktif organ donation. Some ijtihad instruments which are compatible will be aplicated based on the issuess. Research findings about perubatan issuess gave fact that there were not exact explanations on al-Qur’an and al-Sunnah also did not directly examined on fiqh book in the past. This condition cause contemporary ijtihad on those studies as an important study to give law answer about perubatan issues appear. Generally speaking, the current studies require the sinergized between the dynamic of Islamic law and the advance of science and technology.

Immunoferritin localization of intracellular antigens in positively stained frozen sections

1978 ◽  
Vol 36 (2) ◽  
pp. 168-169
Author(s):  
K. T. Tokuyasu
Keyword(s):  
Surface Tension ◽  
Water Surface ◽  
Thin Layers ◽  
The Other ◽  
Positive Staining ◽  
Frozen Sections ◽  
The Past ◽  
Ultrathin Frozen Sections ◽  
Definition Of

During the past investigations of immunoferritin localization of intracellular antigens in ultrathin frozen sections, we found that the degree of negative staining required to delineate u1trastructural details was often too dense for the recognition of ferritin particles. The quality of positive staining of ultrathin frozen sections, on the other hand, has generally been far inferior to that attainable in conventional plastic embedded sections, particularly in the definition of membranes. As we discussed before, a main cause of this difficulty seemed to be the vulnerability of frozen sections to the damaging effects of air-water surface tension at the time of drying of the sections.Indeed, we found that the quality of positive staining is greatly improved when positively stained frozen sections are protected against the effects of surface tension by embedding them in thin layers of mechanically stable materials at the time of drying (unpublished).

Applications of Through-Focus Dark Field Image Shifts to Phase Identification

1975 ◽  
Vol 33 ◽  
pp. 178-179
Author(s):  
Prakash Rao
Keyword(s):  
Dark Field Image ◽  
Thin Foil ◽  
Dark Field ◽  
The Other ◽  
Stereo Image ◽  
Phase Identification ◽  
The Past ◽  
Field Electron Microscopy ◽  
Dark Field Electron ◽  
Recent Extension

Image shifts in out-of-focus dark field images have been used in the past to determine, for example, epitaxial relationships in thin films. A recent extension of the use of dark field image shifts has been to out-of-focus images in conjunction with stereoviewing to produce an artificial stereo image effect. The technique, called through-focus dark field electron microscopy or 2-1/2D microscopy, basically involves obtaining two beam-tilted dark field images such that one is slightly over-focus and the other slightly under-focus, followed by examination of the two images through a conventional stereoviewer. The elevation differences so produced are usually unrelated to object positions in the thin foil and no specimen tilting is required.In order to produce this artificial stereo effect for the purpose of phase separation and identification, it is first necessary to select a region of the diffraction pattern containing more than just one discrete spot, with the objective aperture.

The glycomes of Caenorhabditis elegans and other model organisms

2002 ◽  
Vol 69 ◽  
pp. 117-134 ◽  
Author(s):  
Stuart M. Haslam ◽  
David Gems ◽  
Howard R. Morris ◽  
Anne Dell
Keyword(s):  
Caenorhabditis Elegans ◽  
Current Knowledge ◽  
Structural Data ◽  
Model Organisms ◽  
Entire Genome ◽  
C Elegans ◽  
The Face ◽  
Area Of Concern ◽  
Nematode Worm

There is no doubt that the immense amount of information that is being generated by the initial sequencing and secondary interrogation of various genomes will change the face of glycobiological research. However, a major area of concern is that detailed structural knowledge of the ultimate products of genes that are identified as being involved in glycoconjugate biosynthesis is still limited. This is illustrated clearly by the nematode worm Caenorhabditis elegans, which was the first multicellular organism to have its entire genome sequenced. To date, only limited structural data on the glycosylated molecules of this organism have been reported. Our laboratory is addressing this problem by performing detailed MS structural characterization of the N-linked glycans of C. elegans; high-mannose structures dominate, with only minor amounts of complex-type structures. Novel, highly fucosylated truncated structures are also present which are difucosylated on the proximal N-acetylglucosamine of the chitobiose core as well as containing unusual Fucα1–2Gal1–2Man as peripheral structures. The implications of these results in terms of the identification of ligands for genomically predicted lectins and potential glycosyltransferases are discussed in this chapter. Current knowledge on the glycomes of other model organisms such as Dictyostelium discoideum, Saccharomyces cerevisiae and Drosophila melanogaster is also discussed briefly.

Starch-modified fillers for linerboard and paper grades: A perspective review

TAPPI Journal ◽  
2010 ◽  
Vol 9 (4) ◽  
pp. 31-36 ◽  
Author(s):  
YULIN DENG ◽  
PHIL JONES ◽  
LESLIE MCLAIN ◽  
ART J. RAGAUSKAS
Keyword(s):  
Filler Content ◽  
Product Platform ◽  
Laboratory Studies ◽  
The Past ◽  
Development Opportunity ◽  
Laboratory Results ◽  
Addition Rate ◽  
Institute Of Technology ◽  
Paper Product ◽  
Detrimental Impact

High-filler-content paper is a growing research and development opportunity in papermaking. These new products must address traditional paper product properties while providing papermakers with distinct product platform benefits. Over the past decade, a research team involving researchers from the Institute of Paper Science and Technology at Georgia Institute of Technology and from Imerys have significantly advanced the application of starch-encapsulated papermaking fillers. This review summarizes these accomplishments from initial laboratory studies to mill trials. Laboratory results have illustrated that starch-encapsulated fillers can facilitate a near-doubling of filler content over conventional levels at equal tensile and z-direction tensile (ZDT) values. Equally important is that the use of starch-encapsulated kaolin (SEK) filler has been shown to facilitate a doubling of filler addition rate without any detrimental impact on ring crush compared with control studies with filler. Pilot-plant and mill trials have shown that SEK can function as a fiber extender, reduce steam demand for drying by 10%, and increase papermaking speeds and production rates.

A Qualified Assertion Database for the History of Places

2019 ◽  
Vol 13 (1-2) ◽  
pp. 95-115
Author(s):  
Brandon Plewe
Keyword(s):  
Data Model ◽  
Temporal Change ◽  
Religious Congregations ◽  
Historical Gis ◽  
The Past ◽  
Model Based ◽  
Complex Information ◽  
Invaluable Tool ◽  
History Of ◽  
The Rich

Historical place databases can be an invaluable tool for capturing the rich meaning of past places. However, this richness presents obstacles to success: the daunting need to simultaneously represent complex information such as temporal change, uncertainty, relationships, and thorough sourcing has been an obstacle to historical GIS in the past. The Qualified Assertion Model developed in this paper can represent a variety of historical complexities using a single, simple, flexible data model based on a) documenting assertions of the past world rather than claiming to know the exact truth, and b) qualifying the scope, provenance, quality, and syntactics of those assertions. This model was successfully implemented in a production-strength historical gazetteer of religious congregations, demonstrating its effectiveness and some challenges.

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