scholarly journals Horse Tooth Enamel Ultrastructure: A Review of Evolutionary, Morphological, and Dentistry Approaches

2021 ◽  
Vol 69 (2) ◽  
pp. 67-79
Author(s):  
Vitalii Demeshkant ◽  
Przemysław Cwynar ◽  
Kateryna Slivinska
Keyword(s):  
Experimental Research ◽  
Tooth Enamel ◽  
Morphological Changes ◽  
Feeding Habits ◽  
The Past ◽  
Research Perspectives ◽  
Stage Of Development ◽  
In Captivity ◽  
Breeding Practices

This review searches for and analyzes existing knowledge on horse tooth anatomy in terms of evolutionary and morphological changes, feeding habits, breeding practices, and welfare. More than 150 articles from relevant databases were analyzed, taking into account the issues of our experimental research on the ultrastructure of Equidae tooth enamel. After our analysis, the knowledge on this subject accumulated up in the past, almost 50 years has been logically arranged into three basic directions: evolutionary-palaeontological, morpho-functional, and dentistic, which is also demonstrated by the latest trends in the study of enamel morphology and in the practice of equine dentistry. The obtained data show that in recent years we have observed a rapid increase in publications and a thematic expansion of the scope of research. It is caused by the need to deepen knowledge in theory and in the practice of feeding species in nature and in captivity as well as the possibility of using new technical resources to improve the excellence of such research. It is a summary of the knowledge of a certain stage of equine tooth enamel studies for this period of time, which serves as the basis for our experimental research (the materials are prepared for publication) and at the same time, defines research perspectives for the next stage of development.

scholarly journals Effect of captivity on morphology: negligible changes in external morphology mask significant changes in internal morphology

2018 ◽  
Vol 5 (5) ◽  
pp. 172470 ◽  
Author(s):  
Stephanie K. Courtney Jones ◽  
Adam J. Munn ◽  
Phillip G. Byrne
Keyword(s):  
Sexual Dimorphism ◽  
Captive Breeding ◽  
Morphological Changes ◽  
External Morphology ◽  
Wild Animals ◽  
Internal Morphology ◽  
In Captivity ◽  
Two Generations ◽  
Breeding Programmes ◽  
Source Populations

Captive breeding programmes are increasingly relied upon for threatened species management. Changes in morphology can occur in captivity, often with unknown consequences for reintroductions. Few studies have examined the morphological changes that occur in captive animals compared with wild animals. Further, the effect of multiple generations being maintained in captivity, and the potential effects of captivity on sexual dimorphism remain poorly understood. We compared external and internal morphology of captive and wild animals using house mouse ( Mus musculus ) as a model species. In addition, we looked at morphology across two captive generations, and compared morphology between sexes. We found no statistically significant differences in external morphology, but after one generation in captivity there was evidence for a shift in the internal morphology of captive-reared mice; captive-reared mice (two generations bred) had lighter combined kidney and spleen masses compared with wild-caught mice. Sexual dimorphism was maintained in captivity. Our findings demonstrate that captive breeding can alter internal morphology. Given that these morphological changes may impact organismal functioning and viability following release, further investigation is warranted. If the morphological change is shown to be maladaptive, these changes would have significant implications for captive-source populations that are used for reintroduction, including reduced survivorship.

scholarly journals Felid Cardiopulmonary Nematodes: Dilemmas Solved and New Questions Posed

Pathogens ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 30
Author(s):  
Donato Traversa ◽  
Simone Morelli ◽  
Angela Di Cesare ◽  
Anastasia Diakou
Keyword(s):  
Respiratory Infections ◽  
Small Animal ◽  
Biological Information ◽  
Scientific Debate ◽  
The Past ◽  
Research Perspectives ◽  
Unexpected Findings ◽  
New Research ◽  
Alternative Routes ◽  
Applied Knowledge

In the past decade cardiopulmonary nematodes affecting felids have become a core research topic in small animal parasitology. In the late 2000s, an increase in studies was followed by unexpected findings in the early 2010s, which have stimulated research teams to start investigating these intriguing parasites. Prolific scientific debate and exchanges have then fostered field and laboratory studies and epi-zootiological surveys. New data have improved basic and applied knowledge, solved dilemmas and posed new questions. This article discusses the past and present background to felid cardiopulmonary nematodes after the last few years of intense scientific research. New data which have demonstrated the key role of Aelurostrongylus abstrusus and Troglostrongylus brevior in causing respiratory infections in domestic cats, and on the nil to negligible current importance of other species, i.e., Troglostrongylus subcrenatus, Oslerus rostratus and Angiostrongylus chabaudi, are presented. Biological information and hypothesized alternative routes of infection are analysed and discussed. Novel identification and taxonomical data and issues are reported and commented upon. On the whole, recent biological, ecological and epi-zootiological information on felid meta-strongyloids is critically analysed, with the aim to answer outstanding questions, stimulate future studies, and underline new research perspectives.

scholarly journals Radiocarbon Dating of Calcined Bones: Where Does the Carbon Come from?

Radiocarbon ◽  
2009 ◽  
Vol 51 (2) ◽  
pp. 601-611 ◽  
Author(s):  
A Zazzo ◽  
J-F Saliège ◽  
A Person ◽  
H Boucher
Keyword(s):  
Radiocarbon Dating ◽  
Tooth Enamel ◽  
Skeletal Remains ◽  
Archaeological Sites ◽  
Carbonate Content ◽  
The Past ◽  
Mineral Fraction ◽  
Different Temperatures ◽  
C Value ◽  
Paleodietary Reconstruction

Over the past decade, radiocarbon dating of the carbonate contained in the mineral fraction of calcined bones has emerged as a viable alternative to dating skeletal remains in situations where collagen is no longer present. However, anomalously low δ13C values have been reported for calcined bones, suggesting that the mineral fraction of bone is altered. Therefore, exchange with other sources of carbon during heating cannot be excluded. Here, we report new results from analyses on cremated bones found in archaeological sites in Africa and the Near East, as well as the results of several experiments aiming at improving our understanding of the fate of mineral and organic carbon of bone during heating. Heating of modern bone was carried out at different temperatures, for different durations, and under natural and controlled conditions, and the evolution of several parameters (weight, color, %C, %N, δ13C value, carbonate content, crystallinity indexes measured by XRD and FTIR) was monitored. Results from archaeological sites confirm that calcined bones are unreliable for paleoenvironmental and paleodietary reconstruction using stable isotopes. Experimental results suggest that the carbon remaining in bone after cremation likely comes from the original inorganic pool, highly fractionated due to rapid recrystallization. Therefore, its reliability for 14C dating should be seen as close to that of tooth enamel, due to crystallographic properties of calcined bones.

scholarly journals PEREMPUAN MENGGUGAT: Telaah Perceraian Wanita Muslimah Berkarir di Kota Medan

2019 ◽  
Vol 42 (2) ◽  
pp. 319
Author(s):  
Fatimah Zuhrah
Keyword(s):  
Early Stage ◽  
Muslim Women ◽  
Qualitative Approach ◽  
Human History ◽  
Religious Observance ◽  
Easy Task ◽  
The Past ◽  
Stage Of Development ◽  
The Ideal

<p><strong>Abstrak:</strong> Baiknya pondasi sebuah rumah tangga secara tidak langsung berpengaruh terhadap jatuh bangunnya sebuah negara, dan sebaliknya rusaknya pondasi sebuah keluarga berpengaruh terhadap merosot dan berkembangnya sebuah negara. Beberapa tahun belakangan ini jumlah permintaan gugat cerai istri terhadap suami mengalami peningkatan terutama dari isteri yang berkarir. Penelitian ini melihat permasalahan yang dibangun dengan menggunakan pendekatan kualitatif fenomenologis untuk melihat dan memahami faktor perceraian wanita muslimah berkarir di kota Medan berdasarkan fenomena, fakta dan data yang peneliti temui di lapangan. Berdasarkan temuan penelitian didapat bahwa untuk menegakkan konsep ideal sebuah keluarga sangat sulit untuk dilakukan pada masa sekarang. Kondisi perkawinan sekarang sangat berbeda dengan masa dahulu dalam pemaknaan relasi suami isteri. Dahulu pernikahan memiliki posisi sangat sakral, pernikahan dianggap sebagai ibadah, sehingga orang takut untuk bercerai, karena cerai dianggap aib dan dosa.</p><p><strong>Abstract:</strong> <strong>Women Prosecute: A Study of Divorce in Careered-Muslim Women in Medan City</strong>. The good foundation of a household indirectly affects the rise and fall of a country, and vice versa, the damage to a family’s foundation affects the decline and development of a country. In the last decade, the number of divorce petition against husbands has increased, especially from careered-wives. This paper attempts to study the problems using a phenomenological qualitative approach to thoroughly comprehend the factors of divorce of careered-Muslim women in Medan city based on the phenomena, facts and data that researchers encountered in the field. This study finds that to enforce the ideal concept of a family is not an easy task to do at present. The current condition and perception of marital tie within the society is very different from the past. At the early stage of development of human history, marriage were regarded as inherent in religious observance, and thus, people were reluctant to divorce since it was a disgrace and sin.</p><p><strong>Kata Kunci:</strong> gender, feminisme, cerai, wanita karir, Muslimah</p>

scholarly journals Comparing skull formation of the Hungarian (Hortobágy) Zackel sheep breed by geometrics morphometrics

2015 ◽  
pp. 29-33
Author(s):  
Zsuzsanna Csóri ◽  
András Gáspárdy ◽  
András Jávor
Keyword(s):  
Morphological Changes ◽  
Time Change ◽  
Carpathian Basin ◽  
Sheep Breed ◽  
Geometric Morphometric ◽  
The Past ◽  
Morphometric Methods ◽  
Skull Formation ◽  
Over Time

This work seeks to explore the morphological changes of the Hungarian (Hortobágy) Zackel sheep's skull, which occurred in the past 50–70 years. In this study, we compared individuals skull forms by geometric morphometric methods. The origin of the breed is not known, we do not know when entering the Carpathian Basin. Therefore, the comparison involved the only known early archaeological findings. We have shown that there is no difference between each period colour variations, but over time change has occurred in the skull formation of the breed.

scholarly journals Communicative Perspectives on Strategic Organization

2021 ◽  
Vol 19 (4) ◽  
pp. 541-552
Author(s):  
Eero Vaara ◽  
Ann Langley
Keyword(s):  
Rich Variety ◽  
The Past ◽  
Research Perspectives ◽  
Present Essay ◽  
Language And Communication ◽  
Future Work ◽  
Mainstream Literature

While in the past, perspectives that focus on language and communication have perhaps not received the attention they deserve in the mainstream literature in strategy and organization, interest in this area has been growing in recent years. The present essay serves to introduce a collection of insightful papers (independently submitted and reviewed, but brought together in this themed issue) that offer an opportunity to reflect on the contributions of a rich variety of research perspectives on communication to research in strategic organization. Building on the seven contributions featured in this issue, we show how communicative perspectives speak to questions of the who, how, what, and what then, of strategy. We then discuss dualisms that underpin research on strategic organization adopting a communicative lens and propose directions for future work that might bridge these divides.

scholarly journals Past and current evidence of persecution of the Endangered crowned eagle Harpyhaliaetus coronatus in Argentina

Oryx ◽  
2006 ◽  
Vol 40 (3) ◽  
pp. 347-350 ◽  
Author(s):  
José Hernán Sarasola ◽  
Juan José Maceda
Keyword(s):  
Causes Of Death ◽  
Current Evidence ◽  
Future Research ◽  
Conservation Action ◽  
Field Surveys ◽  
The Past ◽  
Central Argentina ◽  
Water Trough ◽  
Educational Programmes ◽  
In Captivity

The crowned eagle Harpyhaliaetus coronatus is a large Neotropical eagle categorized as Endangered throughout its range. However, the threats to this species are poorly understood. We present data on the causes of death of crowned eagles in semi-arid forests of La Pampa province, central Argentina. Data was obtained from field surveys and from interviews with 62 local landowners during 1999–2004. Over this period five eagles were shot, one killed by a car, one was found dead in a cattle water trough, and one was found in captivity. From the interviews information was obtained about a further 10 cases of eagles being shot, disturbed or trapped. Five (13%) of 38 interviewed landowners who positively identified the species admitted having killed or disturbed eagles in the past but only two (5%) mentioned predation of eagles upon livestock as a problem. Persecution seems to be a significant threat to this species in central Argentina and future research and conservation action should be focused not only on gaining a better knowledge of the biology of the species but also on conservation and educational programmes involving local people.

Research Perspectives on Functional Micro and Nano Scale Coatings

2020 ◽  
pp. 1076-1109
Author(s):  
Jaime Andrés Pérez Taborda ◽  
Elvis O. López
Keyword(s):  
Drug Delivery ◽  
Acoustic Wave ◽  
Aluminum Nitride ◽  
Dielectric Material ◽  
Tooth Enamel ◽  
Wide Band ◽  
Medical Applications ◽  
Wide Band Gap ◽  
Research Perspectives ◽  
Acoustic Wave Sensor

Research topics related to the production of nanocomposites are the most important directions of development of new semiconductor engineering, ensuring high nanocomposites obtaining useful properties in the scope of biophysical characteristics, biomedical and piezoelectric applications. We present two case studies as Hydroxyapatite are in medical applications and aluminum nitride as acoustic wave sensor. Hydroxyapatite, is the main inorganic structure of the tooth enamel and bone and is a biomaterial that is commonly used in biomedical applications that involve bone substitution, drug delivery and bone regeneration because of its excellent biocompatibility, high bioactivity and good osseoconductivity. Since the past decade. Aluminum nitride (AlN), an electrical insulating ceramic with a wide band gap of 6.3 eV, is a potentially useful dielectric material very important in fields such as optoelectronic and micro electronics.

scholarly journals On Directional Dendritic Growth and Primary Spacing—A Review

Crystals ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 627 ◽  
Author(s):  
Joel Strickland ◽  
Bogdan Nenchev ◽  
Hongbiao Dong
Keyword(s):  
Experimental Research ◽  
Dendritic Growth ◽  
Primary Spacing ◽  
Process Variables ◽  
Directionally Solidified ◽  
The Past ◽  
Current State ◽  
Growth Problem ◽  
Solidification Parameters ◽  
The Relationship

The primary spacing is intrinsically linked with the mechanical behavior of directionally solidified materials. Because of this relationship, a significant amount of solidification work is reported in the literature, which relates the primary spacing to the process variables. This review provides a comprehensive chronological narrative on the development of the directional dendritic growth problem over the past 85 years. A key focus within this review is detailing the relationship between key solidification parameters, the operating point of the dendrite tip, and the primary spacing. This review critiques the current state of directional dendritic growth and primary spacing modelling, briefly discusses dendritic growth computational and experimental research, and suggests areas for future investigation.

scholarly journals Cation Doping Approach for Nanotubular Hydrosilicates Curvature Control and Related Applications

Crystals ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 654
Author(s):  
Andrei A. Krasilin ◽  
Ekaterina K. Khrapova ◽  
Tatiana P. Maslennikova
Keyword(s):  
Crystal Structure ◽  
Chemical Composition ◽  
Morphological Changes ◽  
High Technology ◽  
Synthetic Approach ◽  
Cation Doping ◽  
The Past ◽  
Technology Applications ◽  
Curvature Control ◽  
Uptake And Release

The past two decades have been marked by an increased interest in the synthesis and the properties of geoinspired hydrosilicate nanoscrolls and nanotubes. The present review considers three main representatives of this group: halloysite, imogolite and chrysotile. These hydrosilicates have the ability of spontaneous curling (scrolling) due to a number of crystal structure features, including the size and chemical composition differences between the sheets, (or the void in the gibbsite sheet and SiO2 tetrahedron, in the case of imogolite). Mineral nanoscrolls and nanotubes consist of the most abundant elements, like magnesium, aluminium and silicon, accompanied by uncontrollable amounts of impurities (other elements and phases), which hinder their high technology applications. The development of a synthetic approach makes it possible to not only to overcome the purity issues, but also to enhance the chemical composition of the nanotubular particles by controllable cation doping. The first part of the review covers some principles of the cation doping approach and proposes joint criteria for the semiquantitative prediction of morphological changes that occur. The second part focuses on some doping-related properties and applications, such as morphological control, uptake and release, magnetic and mechanical properties, and catalysis.

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