scholarly journals Some research on the genus Camellia l. (Theaceae) with representatives in Vietnam

2021 ◽  
Vol 54 (2) ◽  
pp. 5-11
Author(s):  
Quach Van Hoi ◽  
Dau Ba Thin ◽  
Bui Bao Thinh
Keyword(s):  
Molecular Biology ◽  
Leaf Anatomy ◽  
Morphological Characteristics ◽  
Consistent System ◽  
System A

Abstract. Many studies have been conducted to classify the genus Camellia, yet they have not been entirely consistent. Therefore, doing research on some of the taxonomic systems of the genus Camellia will serve as the basis for the classification and arrangement of recently discovered species into a consistent system. A series of studies based on morphology as well as molecular biology techniques, the classification of pollen spores, and the analysis of leaf anatomy were examined. The systems based on morphological characteristics were inherited and widely recognized, thereby becoming an appropriate method to classify the genus Camellia with representatives in Vietnam.

RHYNCHOLITES AND THE PROBLEM OF NARROW AND BROAD CONCEPTION OF TAXONS

2018 ◽  
pp. 12-17 ◽  
Author(s):  
I. R. Khuzina ◽  
V. N. Komarov
Keyword(s):  
Sexual Dimorphism ◽  
Morphological Characteristics ◽  
Mass Scale ◽  
Individual Variability ◽  
Point Of View ◽  
The Other ◽  
New Taxon ◽  
Artificial System ◽  
Broad Understanding

The paper considers a point of view, based on the conception of the broad understanding of taxons. According to this point of view, rhyncholites of the subgenus Dentatobeccus and Microbeccus are accepted to be synonymous with the genus Rhynchoteuthis, and subgenus Romanovichella is considered to be synonymous with the genus Palaeoteuthis. The criteria, exercising influence on the different approaches to the classification of rhyncholites, have been analyzed (such as age and individual variability, sexual dimorphism, pathological and teratological features, degree of disintegration of material), underestimation of which can lead to inaccuracy. Divestment of the subgenuses Dentatobeccus, Microbeccus and Romanovichella, possessing very bright morphological characteristics, to have an independent status and denomination to their synonyms, has been noted to be unjustified. An artificial system (any suggested variant) with all its minuses is a single probable system for rhyncholites. The main criteria, minimizing its negative sides and proving the separation of the new taxon, is an available mass-scale material. The narrow understanding of the genus, used in sensible limits, has been underlined to simplify the problem of the passing the view about the genus to the other investigators and recognition of rhyncholites for the practical tasks.

Neurochemistry of L-Glutamate Transport in the CNS: A Review of Thirty Years of Progress

2001 ◽  
Vol 66 (9) ◽  
pp. 1315-1340 ◽  
Author(s):  
Vladimir J. Balcar ◽  
Akiko Takamoto ◽  
Yukio Yoneda
Keyword(s):  
Molecular Biology ◽  
Glutamate Transport ◽  
Mammalian Brain ◽  
Activity Data ◽  
System A ◽  
Recent Developments ◽  
The Central Nervous System ◽  
Health And Disease ◽  
Disease Analysis

The review highlights the landmark studies leading from the discovery and initial characterization of the Na+-dependent "high affinity" uptake in the mammalian brain to the cloning of individual transporters and the subsequent expansion of the field into the realm of molecular biology. When the data and hypotheses from 1970's are confronted with the recent developments in the field, we can conclude that the suggestions made nearly thirty years ago were essentially correct: the uptake, mediated by an active transport into neurons and glial cells, serves to control the extracellular concentrations of L-glutamate and prevents the neurotoxicity. The modern techniques of molecular biology may have provided additional data on the nature and location of the transporters but the classical neurochemical approach, using structural analogues of glutamate designed as specific inhibitors or substrates for glutamate transport, has been crucial for the investigations of particular roles that glutamate transport might play in health and disease. Analysis of recent structure/activity data presented in this review has yielded a novel insight into the pharmacological characteristics of L-glutamate transport, suggesting existence of additional heterogeneity in the system, beyond that so far discovered by molecular genetics. More compounds that specifically interact with individual glutamate transporters are urgently needed for more detailed investigations of neurochemical characteristics of glutamatergic transport and its integration into the glutamatergic synapses in the central nervous system. A review with 162 references.

scholarly journals Stabilizing interventional instruments in the cardiovascular system: A classification of mechanisms

2021 ◽  
Vol 89 ◽  
pp. 22-32
Author(s):  
Awaz Ali ◽  
Dimitra Dodou ◽  
Gerwin Smit ◽  
Ruben Rink ◽  
Paul Breedveld
Keyword(s):  
Cardiovascular System ◽  
System A

scholarly journals Morphological Characteristics, Classifications and Difficulties in the Use of Diagnostic Criteria for Serrated Lesions of the Large Intestine

2021 ◽  
Author(s):  
Cesar de Souza Bastos Junior ◽  
Vera Lucia Nunes Pannain ◽  
Adriana Caroli-Bottino
Keyword(s):  
Diagnostic Criteria ◽  
Morphological Characteristics ◽  
World Health ◽  
Diagnostic Tools ◽  
Serrated Adenoma ◽  
The Past ◽  
The World ◽  
Serrated Lesions ◽  
Health Organization

Abstract Introduction Colorectal carcinoma (CRC) is the most common gastrointestinal neoplasm in the world, accounting for 15% of cancer-related deaths. This condition is related to different molecular pathways, among them the recently described serrated pathway, whose characteristic entities, serrated lesions, have undergone important changes in their names and diagnostic criteria in the past thirty years. The multiplicity of denominations and criteria over the last years may be responsible for the low interobserver concordance (IOC) described in the literature. Objectives The present study aims to describe the evolution in classification of serrated lesions, based on the last three publications of the World Health Organization (WHO) and the reproducibility of these criteria by pathologists, based on the evaluation of the IOC. Methods A search was conducted in the PubMed, ResearchGate and Portal Capes databases, with the following terms: sessile serrated lesion; serrated lesions; serrated adenoma; interobserver concordance; and reproducibility. Articles published since 1990 were researched. Results and Discussion The classification of serrated lesions in the past thirty years showed different denominations and diagnostic criteria. The reproducibility and IOC of these criteria in the literature, based on the kappa coefficient, varied in most studies, from very poor to moderate. Conclusions Interobserver concordance and the reproducibility of microscopic criteria may represent a limitation for the diagnosis and appropriate management of these lesions. It is necessary to investigate diagnostic tools to improve the performance of the pathologist's evaluation, for better concordance, and, consequently, adequate diagnosis and treatment.

Classification of EEG Mental Patterns by Using Two Scalp Electrodes and Mahalanobis Distance-Based Classifiers

2002 ◽  
Vol 41 (04) ◽  
pp. 337-341 ◽  
Author(s):  
F. Cincotti ◽  
D. Mattia ◽  
C. Babiloni ◽  
F. Carducci ◽  
L. Bianchi ◽  
...  
Keyword(s):  
Mahalanobis Distance ◽  
Brain Computer Interface ◽  
Computer Interface ◽  
Correct Classification ◽  
Interface Area ◽  
System A ◽  
The Brain ◽  
Full Covariance Matrix ◽  
Recording Electrodes

Summary Objectives: In this paper, we explored the use of quadratic classifiers based on Mahalanobis distance to detect mental EEG patterns from a reduced set of scalp recording electrodes. Methods: Electrodes are placed in scalp centro-parietal zones (C3, P3, C4 and P4 positions of the international 10-20 system). A Mahalanobis distance classifier based on the use of full covariance matrix was used. Results: The quadratic classifier was able to detect EEG activity related to imagination of movement with an affordable accuracy (97% correct classification, on average) by using only C3 and C4 electrodes. Conclusions: Such a result is interesting for the use of Mahalanobis-based classifiers in the brain computer interface area.

scholarly journals A Computational Strategy for Classification of Enem Issues Based on Item Response Theory

2020 ◽  
Vol 27 (1) ◽  
pp. 92-111
Author(s):  
Gustavo Henrique Nunes ◽  
Bruno Alberto Soares Oliveira ◽  
Ciniro Aparecido Leite Nametala
Keyword(s):  
High School ◽  
Item Response Theory ◽  
Item Response ◽  
Generation System ◽  
Response Theory ◽  
Hit Rate ◽  
System A ◽  
Intelligent Simulation ◽  
Computational Strategy

The National High School Examination (ENEM) gains each year more importance, as it gradually, replacing traditional vestibular. Many simulations are done almost randomly by teachers or systems, with questions chosen without discretion. With this methodology, if a test needs to be reapplied, it is not possible to recreate it with questions that have the same difficulty as those used in the first evaluation. In this context, the present work presents the development of an ENEM Intelligent Simulation Generation System that calculates the parameters of Item Response Theory (TRI) of questions that have already been applied in ENEM and, based on them, classifies them. in groups of difficulty, thus enabling the generation of balanced tests. For this, the K-means algorithm was used to group the questions into three difficulty groups: easy, medium and difficult. To verify the functioning of the system, a simulation with 180 questions was generated along the ENEM model. It could be seen that in 37.7% of cases this happened. This hit rate was not greater because the algorithm confounded the difficulty of issues that are in close classes. However, the system has a hit rate of 92.8% in the classification of questions that are in distant groups.

scholarly journals Early Iron Age Sword from the Territory of the Middle Yenisei

2021 ◽  
Vol 20 (7) ◽  
pp. 135-143
Author(s):  
Oleg A. Mitko ◽  
Sergey G. Skobelev
Keyword(s):  
Iron Age ◽  
Low Carbon Steel ◽  
Morphological Characteristics ◽  
Early Iron Age ◽  
Low Carbon ◽  
North Caucasus ◽  
Group Iii ◽  
The North ◽  
Minusinsk Basin

Purpose. The article is devoted to the characteristics of a double-edged iron sword, which can be attributed to the unique phenomena of the early Iron Age of the Minusinsk Basin. Results. According to its morphological characteristics, the sword is an increased technological modification of the traditional Tagar dagger. The total length of the sword is 59.5 cm; the width of the lenticular blade in cross-section is about 7 cm. The handle with a volute-like pommel is separated from the blade by a narrow butterfly-shaped crosshair. The length of the hilt is 8 cm, which corresponds to the size of the hilts of most Scythian swords. This is a very small size, since in men the average palm width is about 12 cm. Probably, the rounded outlines of the pommel and narrow crosshairs allow, due to their shape, to hold the short handle of a heavy sword more tightly. Conclusion. According to the classification of O. I. Kura, Scythian swords with a narrow butterfly-shaped crosshair and volute-like pommel are included in Group III, Type II A2 dating from the end of the 5th – 4th centuries BC, which corresponds to the boundary between the Podgorny and Saragashen stages of the Tagar culture. The earliest form of sword hilts with typologically similar forms of crosshairs (kidney-shaped, heart-shaped, butterfly-shaped) with bar-shaped pommels appeared in the North Caucasus in the first half of the 7th century BC. On the territory of the Minusinsk Basin, most morphologically similar daggers are usually dated to the 6th – 4th centuries BC. Before the discovery of the Krasnoyarsk sword, long-bladed iron weapons were not known there. At the same time, swords of the Scythian time were found in the nearest regions of Altai and Kazakhstan. The later appearance of the technology for processing iron in the Minusinsk Basin makes it possible to consider the Krasnoyarsk sword an import item. According to another hypothesis, it belongs to the period of the late 3rd – 2nd centuries BC, when local craftsmen mastered the processing of iron and began to make massive quantities of weapons and tools from low-carbon steel. In doing so, they copied traditional archaic forms.

Sign in / Sign up

Export Citation Format

Share Document