Effect of preservation on fish morphology over time: Implications for morphological studies

Research in our lab is aimed at examining how signaling molecules affect the differentiation of neurons in the developing cortex. Most morphological studies rely on single time point images of cells within a population. It is obviously advantageous to examine changes in individual living cells over time. By combining 2-photon imaging with co-transfection of genes for green fluorescent protein (GFP) and neurotrophins in living neurons, we can asses the effects of these on individual living cells.Individual neurons in brain slices from ferret visual cortex were transfected with GFP using particle mediated gene-transfer, or Biolistics. Using the Helios Gene Gun (Bio-Rad), DNA-coated gold particles are blasted into living brain slices. Neurons are transfected when a gold particle lands in the nucleus. Within 24 to 36 hours individual cells are well-filled with GFP allowing visualization of dendrites, spines, and axons.

Download Full-text

An assessment of the taxonomic status of wild canids in south-eastern New South Wales: phenotypic variation in dingoes

Australian Journal of Zoology ◽

10.1071/zo12006 ◽

2012 ◽

Vol 60 (2) ◽

pp. 73 ◽

Cited By ~ 5

Author(s):

Cameron G. Radford ◽

Mike Letnic ◽

Melanie Fillios ◽

Mathew S. Crowther

Keyword(s):

New South ◽

New South Wales ◽

Visual Assessment ◽

Assessment Methods ◽

Skull Morphology ◽

South Eastern ◽

Morphological Studies ◽

South Wales ◽

Wild Canids ◽

Over Time

In Australia, the genetic integrity of dingoes (Canis lupus dingo) is threatened through hybridisation with feral dogs and consequently the identification of the modern ‘pure’ dingo is ambiguous. There are no accurate classification techniques for dingoes and dingo–dog hybrids in the wild. Genetics, skull morphology and visual assessment are methods currently used, but they often yield contrasting results. We tested skull morphological and visual assessment methods for classifying wild canids in south-eastern New South Wales and examined temporal and geographic trends in skull morphology. Published equations based on discriminant functions revealed varying percentages of dingoes, dogs and their hybrids over time, and did not yield similar results to visual assessment methods. Skull characteristics generally became larger over time but have recently stabilised. Changes in the morphology of the molars were consistent with the occurrence of hybridisation with dogs. Geographic variation was apparent and consistent with Bergmann’s Law, with skulls increasing in size with altitude. This study highlights the importance for improved classification methods of wild canids and the importance of considering geographical variation in morphological studies.

Download Full-text

Improvement of Kaolin Based Geopolymer Coated Wood Substrates for Use in NaOH Molarity

Materials Science Forum ◽

10.4028/www.scientific.net/msf.967.241 ◽

2019 ◽

Vol 967 ◽

pp. 241-249 ◽

Cited By ~ 1

Author(s):

Ramasamy Shamala ◽

Mohd Mustafa Al Bakri Abdullah ◽

Hussin Kamarudin ◽

Huang Yue ◽

Wang Jin

Keyword(s):

Electron Microscopy ◽

Surface Composition ◽

Initial Period ◽

High Demand ◽

Similar Work ◽

Morphological Studies ◽

Bonding Properties ◽

Source Materials ◽

Over Time ◽

Scanning Electron

Geopolymer system which has high demand, especially among carbon conscious end users resulted in various research works on suitable mix designs of geopolymeric materials. There are certain factors that influence the properties of geopolymers such as composition, type and relative amount of alkali activator, NaOH concentration, specific surface composition of source materials, and condition during the initial period of the geopolymerization process. Focus of our work is on the degree of influence NaOH concentration has towards mechanical and bonding properties of kaolin geopolymer coated lumber wood. Other crucial parameters were kept constant at optimum that was deduced based on our earlier findings. The final idea is to create kaolin based coating material that is compatible with wood substrates which leads to a novel finding. To best of our knowledge, no researchers had attempted to do similar work before. Kaolin geopolymer coated lumber wood was prepared with varying NaOH concentration ranging from 2M to 14M. These pepared samples were tested after 7, 28 and 90 days to also analyse the changes in properties of kaolin geopolymer coated lumber wood over time. Samples were then subjected to mechanical and bonding testings such as flexural, adhesive, and water absorption as well. Morphological studies such as scanning electron microscopy were also performed to further evident findings from all testings.

Download Full-text

From residential village to heritage marketplace: evaluation morphological transformation and their use consequences over time in the historic settlement of Al-Wakran, Qatar

Proceedings of the 56th ISOCARP World Planning Congress ◽

10.47472/brdx7943 ◽

2020 ◽

Author(s):

Abida Khan ◽

◽

Mark Major ◽

Keyword(s):

Urban Morphology ◽

The State ◽

Capital City ◽

Clear Understanding ◽

Urban Context ◽

Morphological Transformation ◽

Rapid Urbanization ◽

Morphological Studies ◽

Historic Settlement ◽

Over Time

Many people consider Al Wakrah to be a distinctive settlement for cultural heritage in the State of Qatar. Based on archaeological evidence, the area of Al Wakrah was perhaps the first urban center of Qatar. Originally a fishing and pearling village like the capital city of Doha, globalization and rapid urbanization also characterized the development of Al Wakrah over the last halfcentury, leading to a remarkable transformation in the morphology of the settlement. The paper studies this morphological transformation of Al Wakrah and the consequences for socioeconomic and functional use. In doing so, the paper offers some clarity about the identity and dynamics of Al Wakrah as a traditional heritage district today; specifically, Souq Al Wakrah. We explore this within the context of traditional marketplaces in general, and souqs in the Arab States of the Gulf Cooperation Council (GCC) region in particular. The study explores the symbiotic relationship between urban morphology, land use, and function in settlement form. The purpose is to develop a deeper understanding of urban changes and expansion on the use and experience of Souq Wakrah as a public place today. Researchers apply several representational techniques standard in morphological studies, including analysis of urban spatial networks using space syntax. The findings of the paper indicate the design and planning nature of Souq Wakrah as a contemporary heritage re-creation. It contrasts with more straightforward examples of historic preservation and restoration in other traditional marketplaces of Qatar itself and elsewhere in the world. This situation arose due to the nearcomplete demolition of most historic structures in Al Wakrah during the recent past, except for a few isolated examples. However, a few important ‘traces’ of Al Wakrah’s morphological history remain consistent over time, despite the dramatic transformations in the rest of the settlement over time. The paper concludes by discussing the potential implications for design and planning policy in the protection and preservation of historic resources in the State of Qatar. It argues for the critical importance of developing a clear understanding of the relationship between form, function, and the urban context of such places in future preservation projects.

Download Full-text

Urban Morphological Studies (Concepts, Techniques, and Methods)

Journal of Engineering ◽

10.31026/j.eng.2020.08.08 ◽

2020 ◽

Vol 26 (8) ◽

pp. 100-111

Author(s):

Haider Jasim Essa Al-Saaidy

Keyword(s):

Critical Points ◽

Urban Form ◽

Historical Development ◽

Theoretical Perspective ◽

Urban Morphology ◽

Morphological Studies ◽

French School ◽

Morphological Approach ◽

The City ◽

Over Time

Urban morphological approach (concepts and practices) plays a significant role in forming our cities not only in terms of theoretical perspective but also in how to practice and experience the urban form structures over time. Urban morphology has been focused on studying the processes of formation and transformation of urban form based on its historical development. The main purpose of this study is to explore and describe the existing literature of this approach and thus aiming to summarize the most important studies that put into understanding the city form. In this regard, there were three schools of urban morphological studies, namely: the British, the Italian, and the French School. A reflective comparison between the three schools has been conducted in order to recognize the main critical points among them. Therefore, a theoretical framework is derived.

Download Full-text

A review of methods used to analyse albatross diets—assessing priorities across their range

ICES Journal of Marine Science ◽

10.1093/icesjms/fsw105 ◽

2016 ◽

Vol 73 (9) ◽

pp. 2125-2137 ◽

Cited By ~ 11

Author(s):

Julie C. McInnes ◽

Ben Raymond ◽

Richard A. Phillips ◽

Simon N. Jarman ◽

Mary-Anne Lea ◽

...

Keyword(s):

Gap Analysis ◽

Isotope Analysis ◽

Breeding Site ◽

Conservation Priorities ◽

Morphological Examination ◽

Management Options ◽

Temporal Sampling ◽

Dietary Flexibility ◽

Morphological Studies ◽

Over Time

Abstract Many seabird populations are threatened by interactions with commercial fisheries, and climate change. Understanding their prey requirements and dietary flexibility in this context is important for effective conservation and management. However, changes in the methods used to assess diet, as well as the spatial and temporal coverage of monitoring schemes, may reduce our ability to detect and monitor these marine threats. To help assess conservation priorities linked to diet, we performed a systematic review of 109 albatross diet papers published between 1950 and 2016, which corresponded to 296 studies when stratified by sampling year, breeding site, and breeding species. We assessed the methods used, changes over time, and spatial and temporal sampling coverage by species and island group. Most albatross studies have focused on chick-rearing, and diet during other breeding phases is comparatively poorly known. Furthermore, chicks are more commonly sampled than adults and very rarely immature birds, all of which may differ in diet composition. There was a pronounced shift over time in the preferred method of characterising diet, from the morphological examination of prey remains to stable isotope analysis of tissue. This shift has reduced the volume of detailed taxonomic information available from morphological studies. This difference in resolution hinders the ability to detect changes in prey species, with implications for management of threatened albatrosses and for monitoring broader changes in marine ecosystems. In a knowledge gap analysis for important breeding colonies (with >5% of global population), we identified key sites where existing monitoring has provided a foundation for robust longitudinal diet studies. Maintaining and augmenting these long-term research programmes will enable analyses of the impacts of changing climate and fishing practices on seabird populations and facilitate the timely identification and implementation of management options.

Download Full-text

Social transmission bias and the cultural evolution of folk-economic beliefs

Behavioral and Brain Sciences ◽

10.1017/s0140525x18000365 ◽

2018 ◽

Vol 41 ◽

Cited By ~ 3

Author(s):

David Hirshleifer ◽

Siew Hong Teoh

Keyword(s):

Cultural Evolution ◽

Social Transmission ◽

Cognitive Approach ◽

Economic Problems ◽

Economic Attitudes ◽

The Social ◽

Economic Beliefs ◽

Over Time

AbstractEvolved dispositions influence, but do not determine, how people think about economic problems. The evolutionary cognitive approach offers important insights but underweights the social transmission of ideas as a level of explanation. The need for asocialexplanation for the evolution of economic attitudes is evidenced, for example, by immense variations in folk-economic beliefs over time and across individuals.

Download Full-text

Fine Structural Localization of Acyltransferases Involved in Lipid Synthesis in Intestinal Mucosa.

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100067261 ◽

1970 ◽

Vol 28 ◽

pp. 54-55

Author(s):

R. J. Barrnett ◽

J. A. Higgins

Keyword(s):

Smooth Endoplasmic Reticulum ◽

Lipid Synthesis ◽

Mucosal Cell ◽

Structural Localization ◽

Morphological Studies ◽

Mucosal Cells ◽

Initial Appearance ◽

Sh Group ◽

Hydrolysis Of ◽

Intestinal Mucosal Cells

The main products of intestinal hydrolysis of dietary triglycerides are free fatty acids and monoglycerides. These form micelles from which the lipids are absorbed across the mucosal cell brush border. Biochemical studies have indicated that intestinal mucosal cells possess a triglyceride synthesising system, which uses monoglyceride directly as an acylacceptor as well as the system found in other tissues in which alphaglycerophosphate is the acylacceptor. The former pathway is used preferentially for the resynthesis of triglyceride from absorbed lipid, while the latter is used mainly for phospholipid synthesis. Both lipids are incorporated into chylomicrons. Morphological studies have shown that during fat absorption there is an initial appearance of fat droplets within the cisternae of the smooth endoplasmic reticulum and that these subsequently accumulate in the golgi elements from which they are released at the lateral borders of the cell as chylomicrons.We have recently developed several methods for the fine structural localization of acyltransferases dependent on the precipitation, in an electron dense form, of CoA released during the transfer of the acyl group to an acceptor, and have now applied these methods to a study of the fine structural localization of the enzymes involved in chylomicron lipid biosynthesis. These methods are based on the reduction of ferricyanide ions by the free SH group of CoA.

Download Full-text

Chromic Acid Etching of Polyethylene

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100070801 ◽

1973 ◽

Vol 31 ◽

pp. 72-73

Author(s):

J. D. Muzzy ◽

R. D. Hester ◽

J. L. Hubbard

Keyword(s):

Chromic Acid ◽

Low Cost ◽

Acid Etching ◽

Crystalline Morphology ◽

Bulk Specimen ◽

Morphological Studies ◽

Perfect Form ◽

Molecular Length ◽

Lamellar Texture ◽

Cost Studies

Polyethylene is one of the most important plastics produced today because of its good physical properties, ease of fabrication and low cost. Studies to improve the properties of polyethylene are leading to an understanding of its crystalline morphology. Polyethylene crystallized by evaporation from dilute solutions consists of thin crystals called lamellae. The polyethylene molecules are parallel to the thickness of the lamellae and are folded since the thickness of the lamellae is much less than the molecular length. This lamellar texture persists in less perfect form in polyethylene crystallized from the melt.Morphological studies of melt crystallized polyethylene have been limited due to the difficulty of isolating the microstructure from the bulk specimen without destroying or deforming it.

Download Full-text

Biological and Morphological Studies on Low-Leukemia-Strain Mice with Hodgkin's-Like Neoplasia Induced by Serial Cell-Free Transmission of Leukemic Organs of SJL/J Strain Mice

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100100792 ◽

1968 ◽

Vol 26 ◽

pp. 210-211

Author(s):

S. Fujinaga ◽

K. Maruyama ◽

C.W. Williams ◽

K. Sekhri ◽

L. Dmochowski

Keyword(s):

Tissue Culture ◽

Type A ◽

Reticulum Cell ◽

Type B ◽

Viral Origin ◽

Serial Transfer ◽

Strain Mouse ◽

Morphological Studies ◽

Cell Neoplasm ◽

Free Material

Yumoto and Dmochowski (Cancer Res.27, 2098 (1967)) reported the presence of mature and immature type C leukemia virus particles in leukemic organs and tissues such as lymph nodes, spleen, thymus, liver, and kidneys of SJL/J strain mice with Hodgki's-like disease or reticulum cell neoplasm (type B). In an attempt to ascertain the possibility that this neoplasia may be of viral origin, experiments with induction and transmission of this neoplasm were carried out using cell-free extracts of leukemic organs from an SJL/J strain mouse with spontaneous disease.It has been possible to induce the disease in low-leukemia BALB/c and C3HZB strain mice and serially transfer the neoplasia by cell-free extracts of leukemic organs of these mice. Histological examination revealed the neoplasia to be of either reticulum cell-type A or type B. Serial transfer is now in its fifth passage. In addition leukemic spleen from another SJL/J strain mouse with spontaneous reticulum cell neoplasm (type A) was set up in tissue culture and is now in its 141st serial passage in vitro. Preliminary results indicate that cell-free material of 39th tissue culture passage can reproduce neoplasia in BALB/c mice.

Download Full-text