scholarly journals ESTRUTURA E DINÂMICA EM UMA FLORESTA DENSA DE TERRA FIRME, SUDESTE DO AMAPÁ, BRASIL

Nativa ◽  
2018 ◽  
Vol 6 ◽  
pp. 802
Author(s):  
Ronaldo Oliveira dos Santos ◽  
Rubiene Neto Soares ◽  
Bruno Costa do Rosário ◽  
Robson Borges de Lima ◽  
Jadson Coelho de Abreu
Keyword(s):  
Vertical Structure ◽  
Ecological Groups ◽  
Terra Firme ◽  
The Past ◽  
Structure And Dynamics ◽  
Major Species ◽  
Diameter Structure ◽  
Terra Firme Forest ◽  
Number Of Individuals ◽  
Late Stages

O objetivo deste estudo foi analisar a variação da estrutura diamétrica de uma comunidade arbórea em floresta densa de terra firme e dos principais grupos de espécies de estágios iniciais e tardios de sucessão, bem como caracterizar a estrutura vertical da floresta. Em 2016, foram inventariadas todas as árvores com DAP ≥ 10 cm e mensuradas suas alturas. Em 2017, as árvores foram reamostradas. A estrutura diamétrica foi analisada por meio do quociente “q” De Liocourt para: a comunidade, principais espécies de maior VI e os grupos ecológicos (GE). A análise da estrutura vertical da vegetação foi feita pela distribuição do número de árvores nos estratos, utilizando-se três métodos: (I) – Sanquetta (1995), (II) - Souza (1990), e (III) – Souza et al. (2003). A estrutura diamétrica da comunidade e dos GE no período avaliado foi caracterizada por árvores de pequeno porte nas menores classes de diâmetro. O Método II não trouxe bons resultados sobre o comportamento das espécies no estrato médio por apresentar fortes tendências em concentrar um maior número de indivíduos nesse estrato. Os resultados da estrutura altimétrica e diamétrica demonstraram indicativos que a exploração antrópica no passado alterou a estrutura da floresta.Palavras-chave: espécies amazônicas, “q” De Licocourt, estratificação, incremento. STRUCTURE AND DYNAMICS IN A DENSE OF TERRA FIRME FOREST, SOUTHEAST OF AMAPÁ, BRAZIL ABSTRACT:The study aimed to analyze the variation of the diameter structure of a arboreal community in a dense terra firme forest and the main groups of species of early and late stages of succession, as well as characterize the vertical structure of the forest. In 2016, all trees with DBH ≥ 10 cm were inventoried and their heights measured indirectly. In 2017, the trees were re-measured. The diametric structure was analyzed using the "q" De Liocourt quotient for: the community, major species of higher (VI) and ecological groups (EG). The analysis of the vertical structure of the vegetation was made by the distribution of the number of trees in the strata, using three methods: (I) – Sanquetta (1995), (II) - Souza (1990), and (III) – Souza et al. (2003). The diametric structure of the community and the EG during the period evaluated was characterized by small trees in the smallest diameter classes. Method II did not bring good results on the behavior of the species in the middle stratum because it presents strong tendencies to concentrate a greater number of individuals in this stratum. The results of the altimetric and diametric structure have demonstrated that antropic exploration in the past has altered the structure of the forest.Keywords: amazonian species, “q” De Licocourt, stratification, increment.

Levels of Spatial Variability: The “Community” Problem

1990 ◽  
Vol 5 ◽  
pp. 13-30 ◽  
Author(s):  
D. A. Springer ◽  
A. I. Miller
Keyword(s):  
Community Structure ◽  
Spatial Variability ◽  
Species Distribution ◽  
Distribution Patterns ◽  
The Past ◽  
Structure And Dynamics ◽  
Evolutionary Units ◽  
The Way

The way we view species distribution patterns, particularly at the level commonly referred to as the “community”, has changed over the past 70 years in biology and, subsequently, in paleontology. Because the degree to which species associations can be interpreted as ecological and evolutionary units depends ultimately on recognition and interpretation of faunal spatial variability, we need to understand the nature of this variability at all levels of resolution before we can adequately address questions of “community” structure and dynamics. While it is possible to recognize spatial variability at several levels, from the distributions of individuals within a species to the overall pattern created by the global biota, we must ask whether these patterns really comprise a hierarchy with natural discontinuities (Fig. 1), or whether it is more realistic to view them as a continuous variability spectrum.

Arbuscular mycorrhizal fungal communities along a pedo-hydrological gradient in a Central Amazonian terra firme forest

Mycorrhiza ◽  
2013 ◽  
Vol 24 (1) ◽  
pp. 21-32 ◽  
Author(s):  
Rejane de Oliveira Freitas ◽  
Erika Buscardo ◽  
Laszlo Nagy ◽  
Alex Bruno dos Santos Maciel ◽  
Rosilaine Carrenho ◽  
...  
Keyword(s):  
Arbuscular Mycorrhizal ◽  
Fungal Communities ◽  
Terra Firme ◽  
Terra Firme Forest ◽  
Arbuscular Mycorrhizal Fungal

scholarly journals Water confined in solutions of biological relevance

2020 ◽  
Vol 92 (10) ◽  
pp. 1563-1574
Author(s):  
Marie-Claire Bellissent-Funel
Keyword(s):  
Aqueous Solutions ◽  
Bulk Water ◽  
Biological Macromolecules ◽  
Organic Solutes ◽  
Confined Water ◽  
The Past ◽  
Structure And Dynamics ◽  
Biological Relevance ◽  
The Stability

AbstractIn many relevant situations, water is not in its bulk form but instead attached to some substrates or filling some cavities. We shall call water in the latter environment confined water as opposed to bulk water. It is known that the confined water is essential for the stability and the function of biological macromolecules. In this paper, we provide a review of the experimental and computational advances over the past decades concerning the understanding of the structure and dynamics of water confined in aqueous solutions of biological relevance. Examples involving water in solution of organic solutes (cryoprotectants such as dimethylsulfoxide (DMSO), sugars such as trehalose) are provided.

The Sla2p/HIP1/HIP1R family: similar structure, similar function in endocytosis?

2010 ◽  
Vol 38 (1) ◽  
pp. 187-191 ◽  
Author(s):  
Irit Gottfried ◽  
Marcelo Ehrlich ◽  
Uri Ashery
Keyword(s):  
Interacting Protein ◽  
The Past ◽  
Structure And Dynamics ◽  
Binding Partners ◽  
Conserved Domain ◽  
The Family ◽  
Genetic Techniques ◽  
Close Relatives ◽  
Biochemical Imaging ◽  
Huntingtin Interacting Protein

HIP1 (huntingtin interacting protein 1) has two close relatives: HIP1R (HIP1-related) and yeast Sla2p. All three members of the family have a conserved domain structure, suggesting a common function. Over the past decade, a number of studies have characterized these proteins using a combination of biochemical, imaging, structural and genetic techniques. These studies provide valuable information on binding partners, structure and dynamics of HIP1/HIP1R/Sla2p. In general, all suggest a role in CME (clathrin-mediated endocytosis) for the three proteins, though some differences have emerged. In this mini-review we summarize the current views on the roles of these proteins, while emphasizing the unique attributes of each family member.

scholarly journals Statistical analysis of the structure and dynamics of material and human resources in public education over the past two academic years in Bacau

2010 ◽  
Author(s):  
Eugenia Harja
Keyword(s):  
Higher Education ◽  
Public Education ◽  
Public University ◽  
University Education ◽  
Public Higher Education ◽  
The Public ◽  
Material Resources ◽  
The Past ◽  
Structure And Dynamics ◽  
Material Basis

The public university education in Bacau, represented by “Vasile Alecsandri” University from Bacau has developed over the past two years not only in terms of student numbers, but as human and material resources available to them. After the number of students per teacher, public higher education from Bacau is situated on the second place after Iasi, the number of teachers representing 1% of the country. The structure by scientific degrees of teachers has improved in the last year, reaching over 36% professors and lecturers and 144 PhDs. Over 55% of the teachers are younger than 40 years. The material basis has improved both quantitatively and qualitatively by putting into use a new building, bringing an additional 27 classrooms and 11 seminar rooms and providing the conditions of modern higher education.

scholarly journals FLORISTIC COMPOSITION AND DIVERSITY IN TERRA FIRME FOREST UNDER WATER STRESS IN THE AMAZON

CERNE ◽  
2020 ◽  
Vol 26 (4) ◽  
pp. 403-412
Author(s):  
Ana Maria Moreira Fernandes ◽  
Maria de Lourdes Pinheiro Ruivo ◽  
Antônio Carlos Lola Costa
Keyword(s):  
Water Stress ◽  
Floristic Composition ◽  
Terra Firme ◽  
Terra Firme Forest

THE NONOPERATIVE TREATMENT OF SURGICAL CONDITIONS IN CHILDREN

PEDIATRICS ◽  
1973 ◽  
Vol 51 (3) ◽  
pp. 435-453
Author(s):  
Mark M. Ravitch
Keyword(s):  
Duodenal Ulcer ◽  
Nonoperative Treatment ◽  
Exophthalmic Goiter ◽  
The Past ◽  
Manual Worker ◽  
Good For ◽  
Surgical Conditions ◽  
Late Stages

As the derivation of the word surgeon from its Greek roots indicates–however much to the dismay of today's cerebral practitioners of the craft–the surgeon is a manual worker. The operative act is so central to surgery and to the life of the surgeon that it has come almost to be equated with surgery and, although I decry it, the word surgery frequently replaces the word operation. The fact is, nevertheless, that operation, being the application of a mechanical technique to disease, is properly employed in the solution of mechanical problems. It is true that, in the past and in the present, some of the most brilliant achievements of surgery have been in the cure or correction of dangerous diseases certainly not mechanically caused, for which there was no nonoperative treatment. This was certainly true until recently for exophthalmic goiter and for that matter, while all would agree that ultimately some nonoperative method will prevail, there are many patients still–and children specifically–in whom I, among others, think hyperthyroidism is still best treated by operation. Nothing else is quite so successful as operation in the treatment of duodenal ulcer or most forms of cancer, yet all of us will accept the fact that in the end, since these are, except in their late stages, not mechanical diseases, specific and nonoperative treatments will be devised which will aim at directly reversing the causative mechanisms. It is precisely in this sort of a search that surgeons are constantly engaged. True enough, as surgeons, we believe that operations are unequivocally good for people.

scholarly journals Lyme Disease Biosensors: A Potential Solution to a Diagnostic Dilemma

Biosensors ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 137
Author(s):  
Connor Flynn ◽  
Anna Ignaszak
Keyword(s):  
Lyme Disease ◽  
Large Degree ◽  
Diagnostic Methods ◽  
Diagnostic Dilemma ◽  
The Past ◽  
Current State ◽  
The World ◽  
Chemical Techniques ◽  
Late Stages ◽  
Current Standards

Over the past four decades, Lyme disease has remained a virulent and pervasive illness, persisting throughout North America and many other regions of the world. Recent increases in illness in many countries has sparked a renewed interest in improved Lyme diagnostics. While current standards of diagnosis are acceptable for the late stages of the disease, it remains difficult to accurately diagnose early forms of the illness. In addition, current diagnostic methods tend to be relatively expensive and require a large degree of laboratory-based analysis. Biosensors represent the fusion of biological materials with chemical techniques to provide simple, inexpensive alternatives to traditional diagnostic methods. Lyme disease biosensors have the potential to better diagnose early stages of the illness and provide possible patients with an inexpensive, commercially available test. This review examines the current state of Lyme disease biosensing, with a focus on previous biosensor development and essential future considerations.

scholarly journals Floristic, structural, and allometric equations to estimate arboreal volume and biomass in a cerradão site

2017 ◽  
Vol 38 (4) ◽  
pp. 1691
Author(s):  
Eder Pereira Miguel ◽  
Alba Valéria Rezende ◽  
Fabrício Assis Leal ◽  
Eraldo Aparecido Trondoli Matricardi ◽  
José Marcelo Imana Encinas ◽  
...  
Keyword(s):  
Tree Species ◽  
Vertical Structure ◽  
Diversity Index ◽  
Species Group ◽  
Systematic Sampling ◽  
Ecological Groups ◽  
Floristic Diversity ◽  
Importance Value ◽  
Horizontal Structure ◽  
Standing Trees

This objective of this study was to characterize the floristic, structural, and ecological groups and to estimate the arboreal volume and biomass of a cerradão site in Palmas, Tocantins, Brazil. A forest inventory was conducted on 10.15 ha of the study area. Plots of 400-m2 were used for systematic sampling. All standing trees (dead or alive) with a breast-height diameter (DHB) greater than 5 cm were identified and measured. Floristic diversity and horizontal structure were assessed using the Shannon and importance value indices, respectively. Forest vertical structure was classified into three stratata and the tree species were categorized into ecological groups. Ninety tree volumes were rigorously cubed and weighed. Fresh- and dry biomass were sampled and estimated. Mathematical models were applied and adjusted to estimate tree volume and biomass. It was observed that the species Myrcia splendens and Emmotum nitens and the families Fabaceae and Chrysobalanaceae were dominant in our study site. The pioneer (613 individuals ha-1) and climax (530 individuals ha-1) tree species group predominated. The floristic diversity index was estimated as 3.35 nats ind- 1. The vertical structure analysis indicated fewer individuals in the superior stratum (13%) compared to the medium (63%) and inferior (24%) stratum. The Schumacher and Hall model showed better results with regard to estimated forest production. Forest volume and biomass estimates were 126.71 m³ ha-1 and 61.67 Mg ha-1, respectively. The studied cerradão area had high floristic diversity and climax species predominated. Since this cerradão is in close proximity to the Amazon biome, its volume and biomass stocks were higher than those estimated for other cerradão and forest formations within the Cerrado biome.

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