scholarly journals The evolution of growth patterns in mammalian versus nonmammalian cynodonts

Paleobiology ◽  
2016 ◽  
Vol 42 (3) ◽  
pp. 439-464 ◽  
Author(s):  
Rachel N. O’Meara ◽  
Robert J. Asher
Keyword(s):  
Function Analysis ◽  
Growth Patterns ◽  
Adult Size ◽  
Juvenile Growth ◽  
Evolutionary Transitions ◽  
Fossil Species ◽  
Adult Growth ◽  
Distribution Shape ◽  
Gradual Evolution

AbstractOne of the major evolutionary transitions of the mammaliaform lineage was the origin of a typically mammalian pattern of growth. This is characterized by rapid juvenile growth followed by abrupt cessation of growth at adult size and may be linked with other important mammaliaform apomorphies of dental replacement and morphology. Investigation of growth patterns in the tritylodontid cynodont Oligokyphus and the basal mammaliaform Morganucodon provides insight into this crucial transition. We collected mandibular depth measurements from large samples of Morganucodon and Oligokyphus and constructed distributions of mandibular depth versus frequency for each species. These were compared with distributions from species from three different growth classes of extant amniote: testudines + crocodilians, mammals + birds, and lepidosaurs. Discriminant function analysis was used to differentiate between known growth classes by using different combinations of three measures of mandibular depth distribution shape (skew, kurtosis, and coefficient of variation) as proxies for different juvenile and adult growth patterns. Classification of the fossil species showed that Morganucodon closely resembled extant placental mammals in having rapid juvenile growth followed by truncated, determinate adult growth. Oligokyphus showed intermediate growth patterns, with more extended adult growth patterns than Morganucodon and slightly slower juvenile growth. This suggests a gradual evolution of mammalian growth patterns across the cynodont to mammaliaform transition, possibly with the origin of rapid juvenile growth preceding that of truncated, determinate adult growth. In turn, acquisition of both these aspects of mammalian growth was likely necessary for the evolution of diphyodont tooth replacement in the mammaliaform lineage.

scholarly journals Enamel formation and growth in non-mammalian cynodonts

2018 ◽  
Vol 5 (5) ◽  
pp. 172293 ◽  
Author(s):  
Rachel N. O'Meara ◽  
Wendy Dirks ◽  
Agustín G. Martinelli
Keyword(s):  
Growth Rates ◽  
Polarized Light ◽  
Growth Patterns ◽  
Juvenile Growth ◽  
Tooth Replacement ◽  
Replacement Rate ◽  
Adult Growth ◽  
Evolution Of Mammals ◽  
Additional Explanation ◽  
Incremental Lines

The early evolution of mammals is associated with the linked evolutionary origin of diphyodont tooth replacement, rapid juvenile growth and determinate adult growth. However, specific relationships among these characters during non-mammalian cynodont evolution require further exploration. Here, polarized light microscopy revealed incremental lines, resembling daily laminations of extant mammals, in histological sections of enamel in eight non-mammalian cynodont species. In the more basal non-probainognathian group, enamel extends extremely rapidly from cusp to cervix. By contrast, the enamel of mammaliamorphs is gradually accreted, with slow rates of crown extension, more typical of the majority of non-hypsodont crown mammals. These results are consistent with the reduction in dental replacement rate across the non-mammalian cynodont lineage, with greater rates of crown extension required in most non-probainognathians, and slower crown extension rates permitted in mammaliamorphs, which have reduced patterns of dental replacement in comparison with many non-probainognathians. The evolution of mammal-like growth patterns, with faster juvenile growth and more abruptly terminating adult growth, is linked with this reduction in dental replacement rates and may provide an additional explanation for the observed pattern in enamel growth rates. It is possible that the reduction in enamel extension rates in mammaliamorphs reflects an underlying reduction in skeletal growth rates at the time of postcanine formation, due to a more abruptly terminating pattern of adult growth in these more mammal-like, crownward species.

scholarly journals Two unusual new species of Caleremaeus (Acari: Oribatida) from eastern North America, with redescription of C. retractus and reevaluation of the genus

Acarologia ◽  
2020 ◽  
Vol 60 (2) ◽  
pp. 398-448
Author(s):  
Roy A. Norton ◽  
Valerie M. Behan-Pelletier
Keyword(s):  
New Species ◽  
Oribatid Mite ◽  
Adult Size ◽  
Transverse Ridge ◽  
Fossil Species ◽  
The North ◽  
Extant Species ◽  
The Family ◽  
Eastern Usa

The oribatid mite genus Caleremaeus (Caleremaeidae) is widely distributed in the northern hemisphere but has been represented by only three extant and one fossil species. We redescribe the North American C. retractus (Banks, 1947) based on adults and nymphs; it is distinguishable from the European type species, C. monilipes (Michael, 1882) by its smaller adult size and minor differences in cuticular structure, and by the elongated, tapered form of seta h1 in nymphs. Two new species are proposed: C. nasutus n. sp. from forest soil in Alabama is unique in having adults with a large anterior rostral lobe (juveniles unknown) bearing lamellar setae; the arboreal C. arboricolus n. sp. from eastern USA and Canada is unique among described extant species in having adults with femoral saccules, a transverse ridge bearing lamellar setae and relatively large notogastral setae, and juveniles with a bothridial seta similar to that of the adult. Based on all available data, Caleremaeus is redescribed and considered the sole genus in Caleremaeidae. The higher classification of the family is reviewed, and past placement in Ameroidea is rejected in favor of the monofamilial Caleremaeoidea.

Diagnostic Value of Electron Microscopy in Soft Tissue Tumors

1970 ◽  
Vol 28 ◽  
pp. 220-221
Author(s):  
Gerald Fine ◽  
Azorides R. Morales
Keyword(s):  
Cardiac Myxoma ◽  
Osteogenic Sarcoma ◽  
Diagnostic Value ◽  
Soft Tissue Tumors ◽  
Amelanotic Melanoma ◽  
Growth Patterns ◽  
Light Microscopic Level ◽  
Mesenchymal Tumors ◽  
Good Agreement

For years the separation of carcinoma and sarcoma and the subclassification of sarcomas has been based on the appearance of the tumor cells and their microscopic growth pattern and information derived from certain histochemical and special stains. Although this method of study has produced good agreement among pathologists in the separation of carcinoma from sarcoma, it has given less uniform results in the subclassification of sarcomas. There remain examples of neoplasms of different histogenesis, the classification of which is questionable because of similar cytologic and growth patterns at the light microscopic level; i.e. amelanotic melanoma versus carcinoma and occasionally sarcoma, sarcomas with an epithelial pattern of growth simulating carcinoma, histologically similar mesenchymal tumors of different histogenesis (histiocytoma versus rhabdomyosarcoma, lytic osteogenic sarcoma versus rhabdomyosarcoma), and myxomatous mesenchymal tumors of diverse histogenesis (myxoid rhabdo and liposarcomas, cardiac myxoma, myxoid neurofibroma, etc.)

The twelve-month outcome of patients with neurotic illness in general practice

1981 ◽  
Vol 11 (3) ◽  
pp. 535-550 ◽  
Author(s):  
A. H. Mann ◽  
R. Jenkins ◽  
E. Belsey
Keyword(s):  
Social Life ◽  
Function Analysis ◽  
Psychiatric Morbidity ◽  
The Social ◽  
Assessment Measures ◽  
Psychiatric State ◽  
One Year

SYNOPSISOne hundred patients, selected to be representative of those attending general practitioners with non-psychotic psychiatric disorders were followed up for one year. standard assessments of mental state, personality, social stresses and supports were carried out for each patient at the outset and after a year.The outcome for this cohort determined both by the level of psychiatric morbidity at interview after one year and by the pattern of the psychiatric morbidity during the year has been analysed with reference to the assessment measures. Discriminant function analysis indicates that the initial estimate of the severity of the psychiatric morbidity and a rating of the quality of the social life at the time of follow-up are the only factors that significantly predict the psychiatric state after one year. Social measures also predict a pattern of illness charactorized by a rapid recovery after the initial assessemtn. Patients who reported continuous psychiatric morbidity during the year were, older, physically ill and very likely to have recevied psychotropic drugs. Receipt of this medication during the year was associated with initial assessments of abnormality of personality, older age, and a diagnosis of depression.The findings of this study are seen to support a triaxial assessment and classification of non-psychotic psychiatirc disorders, with symptoms, personality and social state being rated independently.

scholarly journals Differences in the whistle characteristics and repertoire of Bottlenose and Spinner Dolphins

2004 ◽  
Vol 76 (2) ◽  
pp. 386-392 ◽  
Author(s):  
Carmen Bazúa-Durán
Keyword(s):  
Geographic Variation ◽  
Discriminant Function Analysis ◽  
Bottlenose Dolphin ◽  
Function Analysis ◽  
Bottlenose Dolphins ◽  
Constant Frequency ◽  
Spinner Dolphin ◽  
Time Parameters ◽  
Spinner Dolphins

Several methods have been used to compare the whistles produced by dolphins. The two methods used in this study are: (1) a classification of whistle contours in six categories (i.e. constant frequency, upsweep, downsweep, concave, convex, and sine) and (2) the extraction of frequency and time parameters from each whistle contour. Bottlenose Dolphin Tursiops truncatus whistles are described in the same way when comparing whistle contour distributions in each of the six categories and whistle frequency and time parameters using Discriminant Function Analysis. For Spinner Dolphin Stenella longirostris whistles, each method describes whistles differently. Several facts may explain these differences in describing dolphin whistles, such as a greater fluidity of Spinner Dolphin groups when compared to Bottlenose Dolphin groups, greater geographic variation in the whistles of Bottlenose Dolphins than in those of Spinner Dolphins, an average beginning frequency 16% lower than the average ending frequency in Spinner Dolphin whistles compared to a varied relationship for Bottlenose Dolphins, and stricter criteria used to define whistle contour categories in the study of Spinner Dolphin whistles than in the Bottlenose Dolphin whistle study.

scholarly journals Discrimination study between carcass yield and meat quality by gender in Korean native cattle (Hanwoo)

2020 ◽  
Vol 33 (7) ◽  
pp. 1202-1208
Author(s):  
Do-Gyun Kim ◽  
Joon-Yong Shim ◽  
Byoung-Kwan Cho ◽  
Collins Wakholi ◽  
Youngwook Seo ◽  
...  
Keyword(s):  
Meat Quality ◽  
Function Analysis ◽  
Statistical Significance ◽  
Significance Test ◽  
Carcass Yield ◽  
Yield And Quality ◽  
Quality Grade ◽  
Native Cattle

Objective: The aim of this study was to identify a distribution pattern of meat quality grade (MQG) as a function of carcass yield index (CYI) and the gender of Hanwoo (bull, cow, and steer) to determine the optimum point between both yield and quality. We also attempted to identify how pre- and post-deboning variables affect the gender-specific beef quality of Hanwoo.Methods: A total of 31 deboning variables, consisting of 7 pre-deboning and 24 post-deboning variables from bulls (n = 139), cows (n = 69), and steers (n = 153), were obtained from the National Institute of Animal Science (NIAS) in South Korea. The database was reconstructed to be suitable for a statistical significance test between the CYI and the MQG as well as classification of meat quality. Discriminant function analysis was used for classifying MQG using the deboning parameters of Hanwoo by gender.Results: The means of CYI according to 1+, 1, 2, and 3 of MQG were 68.64±2.02, 68.85±1.94, 68.62±5.88, and 70.99±3.32, respectively. High carcass yield correlated with low-quality grade, while high-quality meat most frequently was obtained from steers. The classification ability of pre-deboning parameters was higher than that of post-deboning parameters. Moisture and the shear force were the common significant parameters in all discriminant functions having a classification accuracy of 80.6%, 71%, and 56.9% for the bull, cow, and steer, respectively.Conclusion: This study provides basic information for predicting the meat quality by gender using pre-deboning variables consistent with the actual grading index.

scholarly journals Classification of fish and non-fish acoustic tracks using discriminant function analysis

2012 ◽  
Vol 69 (2) ◽  
pp. 313-322 ◽  
Author(s):  
Yunbo Xie ◽  
Catherine G. J. Michielsens ◽  
Fiona J. Martens
Keyword(s):  
Discriminant Function ◽  
Discriminant Function Analysis ◽  
Function Analysis ◽  
Fish Populations ◽  
Fraser River ◽  
Discriminating Power ◽  
Sonar System ◽  
Stationary Objects ◽  
Individual Variables

Abstract Xie, Y., Michielsens, C. G. J., and Martens, F. J. 2012. Classification of fish and non-fish acoustic tracks using discriminant function analysis. – ICES Journal of Marine Science, 69: 313–322. Hydroacoustic data acquired for estimating fish populations contain information on both fish and non-fish targets, so sonar technicians traditionally rely on their knowledge of fish behaviour and experience with hydroacoustics to remove non-fish targets from the hydroacoustic data. This process is often labour-intensive and time-consuming, making real-time assessment of fish populations difficult. Simple solutions are not always available for all circumstances. However, the split-beam sonar data collected in the lower Fraser River, British Columbia, Canada, showed distinct signatures between actively swimming fish and non-fish objects such as drifting debris, surface bubbles, and stationary objects in the water column and off the river bottom. Acoustic tracks of fish and non-fish targets were characterized by differentiable statistical patterns that were amenable to discriminant function analysis (DFA). An application of DFA to segregate fish and non-fish targets detected by a split-beam sonar system in the lower Fraser River is presented, characteristics of user-identified fish and non-fish acoustic tracks being utilized as learning samples for the DFA. Also, a method to rank the discriminating power of individual variables is presented, providing guidance for constructing efficient and effective discriminant functions with variables that offer high discriminating power. The DFA yielded classification accuracies of 96% for fish and 91% for non-fish tracks and reduced the manual sorting time by 50–75%.

Research on Electric and I&C Equipment Safety Function Classification of Nuclear Power Plant

2021 ◽  
Author(s):  
Wang Yuqi ◽  
Sun Qian
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Nuclear Power ◽  
Power Plants ◽  
Function Analysis ◽  
System Component ◽  
Design Work ◽  
Equipment Safety ◽  
Safety Function

Abstract Classification of System, Component and Structure (SSC) is the base as well as high level demand of nuclear power plant. Equipment classification including electric and Instrument and Control (I&C) equipment is the precondition of correct design regulation and standard. Safety function classification is key pass of electric and I&C equipment classification. This paper researches the method of nuclear power plant electric and I&C equipment safety function classification. Firstly from view of function, it explains the importance of function classification. Then function analysis and classification of equipment is implemented by design order. Lastly from view of accident analysis, function classification is validated, and a complete approach of function classification is formed. The purpose of this paper is the NPP electric and I&C equipment safety function classification as an example, to study and summarize the method of the electric and I&C equipment safety function classification, and to provide the basis for specific items design work according to design requirements. At the same time, a practical method is provided for other similar NPP electric and I&C equipment classification work. The electric and I&C equipment function classification of nuclear power plant satisfy the basic principles requirement of relative nuclear power rules and codes. It provides an important basis of equipment classification for next nuclear power plants.

scholarly journals Patterns of Growth in Nestling Indian Barn-Owls

The Condor ◽  
2002 ◽  
Vol 104 (4) ◽  
pp. 885-890 ◽  
Author(s):  
Rajarathinavelu Nagarajan ◽  
Krishinamoorthy Thiyagesan ◽  
Rajagopalan Natarajan ◽  
Ramalingam Kanakasabai
Keyword(s):  
Body Mass ◽  
Body Length ◽  
Wing Length ◽  
Growth Patterns ◽  
The Body ◽  
Logistic Growth ◽  
Adult Size ◽  
Tyto Alba ◽  
Tarsus Length ◽  
Bill Length

Abstract We examined nestling growth patterns of the Indian Barn-Owl (Tyto alba stertens) in Tamilnadu, Southern India, with reference to body mass, body length, bill length, bill width, wing length, wingspan, tail length, tarsus length, and middle claw length. Body mass reached an asymptote of 447.0 ± 6.8 g during week 7, which was 10% higher than the adult mass. Then it significantly declined to 437.0 ± 10.9 g at fledging. At the end of week 4, the body length, bill length, bill width, tarsus length, and middle toe length had surpassed 50% of adult sizes. The wingspan and tarsus length reached almost adult size by the time of fledging. A logistic growth curve was found to be a good fit for all the growth variables and explained between 71% (wing length) and 86% (body length) of the variance. Patrones de Crecimiento en Polluelos de Tyto alba stertens Resumen. Examinamos los patrones de crecimiento de polluelos de Tyto alba stertens en Tamilnadu, sudoeste de India, en relación al peso y el largo del cuerpo, el largo y el ancho del pico, el largo del ala y su envergadura, y el largo de la cola, los tarsos y de la garra mediana. El peso corporal alcanzó una asíntota de 447.0 ± 6.8 g durante la séptima semana, el cual fue un 10% mayor que el peso de los adultos. Posteriormente, durante el período de volantones, el peso corporal disminuyó hasta 437.0 ± 10.9 g. Al final de la cuarta semana, el largo del cuerpo, el largo y el ancho del pico, y los largos del tarso y del dedo mediano habían sobrepasado el 50% de los tamaños adultos. La envergadura del ala y el largo del tarso casi alcanzaron tamaños adultos durante el período de volantones. Se encontró que una curva de crecimiento logístico se ajustó bien a todas las variables de crecimiento y explicó un 71% (largo del ala) y un 86% (largo del cuerpo) de la varianza.

scholarly journals Innovative microfossil (radiolarian) analysis using a system for automated image collection and AI-based classification of species

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Takuya Itaki ◽  
Yosuke Taira ◽  
Naoki Kuwamori ◽  
Hitoshi Saito ◽  
Minoru Ikehara ◽  
...  
Keyword(s):  
Artificial Intelligence System ◽  
Fossil Species ◽  
Human Expert ◽  
Intelligence System ◽  
Geological Age ◽  
Computer Controlled ◽  
Classification Tasks ◽  
Image Collection

AbstractMicrofossils are a powerful tool in earth sciences, and they have been widely used for the determination of geological age and in paleoenvironmental studies. However, the identification of fossil species requires considerable time and labor by experts with extensive knowledge and experience. In this study, we successfully automated the acquisition of microfossil data using an artificial intelligence system that employs a computer-controlled microscope and deep learning methods. The system was used to calculate changes in the relative abundance (%) of Cycladophora davisiana, a siliceous microfossil species (Radiolaria) that is widely used as a stratigraphic tool in studies on Pleistocene sediments in the Southern Ocean. The estimates obtained using this system were consistent with the results obtained by a human expert (< ± 3.2%). In terms of efficiency, the developed system was capable of performing the classification tasks approximately three times faster than a human expert performing the same task.

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