scholarly journals Key Elements of the White-Backed Woodpecker’s (Dendrocopos leucotos lilfordi) Habitat in Its European South-Western Limits

Forests ◽  
2020 ◽  
Vol 11 (8) ◽  
pp. 831
Author(s):  
Ainhoa Urkijo-Letona ◽  
Susana Cárcamo ◽  
Lorena Peña ◽  
Beatriz Fernández de Manuel ◽  
Miren Onaindia ◽  
...  
Keyword(s):  
Sustainable Management ◽  
Structural Heterogeneity ◽  
Suitable Habitat ◽  
Structural Elements ◽  
Fomes Fomentarius ◽  
The Past ◽  
Intensive Forest Management ◽  
Breeding Habitats ◽  
Special Area ◽  
High Diversity

In the last decade, the population of the white-backed woodpecker (Dendrocopos leucotos lilfordi) (WBW) in Navarre has been reduced mainly due to the loss of suitable habitat for this species from intensive forest management, leading almost to its extinction. This study aimed to identify the key structural elements of breeding habitats of the WBW and analyze their effect on the composition of the saproxylic fungi community within the habitats. In the Special Area of Conservation, namely Quinto Real in Navarre, 20 circular plots (500 m2) and 10 transects (150–300 m) were located inside and outside WBW territories. Within each sample plot, forest structure, deadwood, microhabitats, regeneration, and saproxylic fungi community were studied. The results showed that the key elements in the WBW territories were high trees, high diversity of deadwood (with a high presence of big and late-decay deadwood), high snag volume, and high microhabitat diversity. Although the past management is also evident in the variability of some of those characteristics, this species is well adapted to different structural and compositional conditions of the territory. The saproxylic fungi community was richer among the WBW territories, and in those areas, the presence of Fomes fomentarius was high, compared to non-WBW territories where it was not present. In conclusion, to maintain and protect the studied population, it is necessary to implement sustainable management that guarantees the conservation of the key elements for the WBW territories (structural heterogeneity and high deadwood diversity) in order to increase the suitability of the habitat for WBWs.

An old bridge transformed into a new one: possible, recommendable?

2019 ◽  
Author(s):  
Diego Carro-López ◽  
Ignasi Fernandez ◽  
Natalie Williams Portal
Keyword(s):  
Environmental Issues ◽  
Quality Standards ◽  
Structural Effect ◽  
Coarse Fraction ◽  
Concrete Bridges ◽  
Recycled Aggregates ◽  
Structural Elements ◽  
The Past ◽  
Reinforced Concrete Bridges ◽  
Natural Aggregates

<p>There is an extensive network of reinforced concrete bridges that give service to roads, highways and railways. These structures where constructed with quality standards of the past, and they suffer of severe problems. Now we consider the idea of substituting them with structural elements with much longer service life. However, there is an important question to be addressed in this area: what to do with the existing infrastructure that would be demolished. Even more if we consider environmental issues.</p><p>One good example of this recurrent problem could be found in the case of the Gullspång bridge (Sweden). It was constructed in 1935 and it was severely damaged with corrosion. The administration decided in the 2016 that no further repair would be done and that the bridge would be demolished and a new erected in substitution. A fraction of the concrete from the old bridge was crushed and processed to produce new aggregate. With this aggregate, using the coarse fraction, it was analyzed the structural effect of replacing natural aggregates with these recycled aggregates. The performance of the new structural elements was positive, and it seems that a high percentage of the natural aggregates could be replaced with recycled ones.</p>

scholarly journals Structure Determination of Microtubules and Pili: Past, Present, and Future Directions

2022 ◽  
Vol 8 ◽  
Author(s):  
James A. Garnett ◽  
Joseph Atherton
Keyword(s):  
Ex Vivo ◽  
Structural Heterogeneity ◽  
Resonance Spectroscopy ◽  
Future Directions ◽  
Computational Approaches ◽  
The Past ◽  
Major Shift ◽  
Technical Innovations

Historically proteins that form highly polymeric and filamentous assemblies have been notoriously difficult to study using high resolution structural techniques. This has been due to several factors that include structural heterogeneity, their large molecular mass, and available yields. However, over the past decade we are now seeing a major shift towards atomic resolution insight and the study of more complex heterogenous samples and in situ/ex vivo examination of multi-subunit complexes. Although supported by developments in solid state nuclear magnetic resonance spectroscopy (ssNMR) and computational approaches, this has primarily been due to advances in cryogenic electron microscopy (cryo-EM). The study of eukaryotic microtubules and bacterial pili are good examples, and in this review, we will give an overview of the technical innovations that have enabled this transition and highlight the advancements that have been made for these two systems. Looking to the future we will also describe systems that remain difficult to study and where further technical breakthroughs are required.

An Evaluation and Comparison of Models for Maximum Deflection of Stiffened Plates Using Finite Element Analysis

2007 ◽  
Vol 44 (04) ◽  
pp. 212-225
Author(s):  
Lior Banai ◽  
Omri Pedatzur
Keyword(s):  
Finite Element ◽  
Orthotropic Plate ◽  
Lateral Pressure ◽  
Stiffened Plates ◽  
Maximum Deflection ◽  
Structural Elements ◽  
The Finite Element Method ◽  
Element Analysis ◽  
The Past ◽  
Different Types

Stiffened plates form the backbone of most of a ship's structure. Today, finite element (FE) models are used to analyze the behavior of such structural elements for different types of loads. In the past, when usage of computers and FE models were not used very much, analytical analysis methods were required. Two well-known methods have been developed for analyses of stiffened plates under lateral loading (uniform pressure), based on two different models, namely, the orthotropic plate model and the grillage model. Both models can give estimations for the maximum plate deflection under uniform lateral pressure. The objective of this paper is to present the two methods, evaluate and compare the methods using the finite element method, and finally implement the methods as a computer program for quick estimations of the maximum deflection of stiffened plates. The degree of accuracy of the two methods when compared to FE is discussed in some detail.

Stress Distribution in Joints in Panel Structures

2015 ◽  
Vol 1124 ◽  
pp. 209-218
Author(s):  
Pavel Svoboda ◽  
Karl Heinz Winter
Keyword(s):  
Practical Experience ◽  
Elastic Behavior ◽  
Complex Structures ◽  
Structural Elements ◽  
Structural Members ◽  
Long Term Effects ◽  
Linear Elastic ◽  
The Past ◽  
Current Design

Reinforced and pre-stressed concrete have been used increasingly for various kinds of complex structures in the past decades. The structures assembled from panels belong into this group. The current design methods rely on linear elastic analyses based on empirically derived material laws assuming homogeneous and isotropic material. Practical experience and various investigations however have indicated that majority of structures and structural elements are in fact stressed beyond the range of linear elastic behavior. In addition, long term effects may have a significant influence on the structural behavior of this category of structures and structural members.

Use of bioclimatic analysis to direct survey effort for the long-footed potoroo (Potorous longipes), a rare forest-dwelling rat-kangaroo

2002 ◽  
Vol 29 (2) ◽  
pp. 193 ◽  
Author(s):  
A. W. Claridge
Keyword(s):  
Environmental Variables ◽  
New Records ◽  
New South ◽  
New South Wales ◽  
Geographic Range ◽  
Suitable Habitat ◽  
The Past ◽  
South Wales ◽  
North Eastern ◽  
Survey Effort

The long-footed potoroo (Potorous longipes) is one of the rarest and most elusive forest-dwelling mammals in Australia. Survey effort for the species over the past decade or so in south-eastern New South Wales has been driven, primarily, by predictions derived from climatic analyses using BIOCLIM. These predictions were based on known locality records of the long-footed potoroo from adjacent East Gippsland, Victoria. While they have proven useful in confirming the occurrence of the species in New South Wales, recent fortuitous records of the species from north-eastern Victoria fall well outside of the range predicted earlier by BIOCLIM. Using these new records a revised predicted range is calculated, enlarging considerably the potential geographic extent of climatically suitable habitat for the species. The results presented here highlight the limitations of BIOCLIM when given locality records of a species from only a portion of its true geographic range. I argue that less emphasis might be based on this approach to direct survey effort for the species in the future. Instead, a range of other environmental variables might be used in combination with BIOCLIM-derived outputs when selecting survey sites. In this way a more representative picture of the distribution of the species may be obtained.

Metalloligand Strategies for Assembling Heteronuclear Nanocages – Recent Developments

2019 ◽  
Vol 72 (10) ◽  
pp. 731 ◽  
Author(s):  
Feng Li ◽  
Leonard F. Lindoy
Keyword(s):  
Structural Properties ◽  
Metal Ion ◽  
Rational Design ◽  
Building Blocks ◽  
Structural Elements ◽  
Present Discussion ◽  
The Past ◽  
Recent Developments ◽  
Metal Organic ◽  
Multifunctional Ligand

The use of metalloligands as building blocks for the assembly of metallo-organic cages has received increasing attention over the past two decades or so. In part, the popularity of this approach reflects its stepwise nature that lends itself to the predesigned construction of metallocages and especially heteronuclear metallocages. The focus of the present discussion is on the use of metalloligands for the construction of discrete polyhedral cages, very often incorporating heterometal ions as structural elements. The metalloligand approach uses metal-bound multifunctional ligand building blocks that display predesigned structural properties for coordination to a second metal ion such that the rational design and construction of both homo- and heteronuclear metal–organic cages are facilitated. The present review covers published literature in the area from early 2015 to early 2019.

COMPARATIVE ANALYSIS OF THE CONTENT OF THE TARAS SHEVCHENKO NATIONAL UNIVERSITY OF KYIV’S LINGUISTIC EDUCATIONAL MUSEUM EXPOSITION WITH SIMILAR INSTITUTIONS IN THE WORLD

2019 ◽  
pp. 26-32
Author(s):  
A. М. Bocharnikova
Keyword(s):  
Comparative Analysis ◽  
The Netherlands ◽  
General Purpose ◽  
The Internet ◽  
National Museum ◽  
Structural Elements ◽  
The Past ◽  
The Us ◽  
The World ◽  
National University

The article contains information on all general-purpose linguistic museums that are currently functioning in the world, functioned in the past, or are at the project stage. In cases where this is possible, the structure of museum’s exposition is examined. Criteria that have played a key role in the division of museums’ content into structural elements are defined. The accuracy of exposition authors’ compliance of their approaches has also been analyzed. The first linguistic museum in the world that opened its doors to visitors was Taras Shevchenko university of Kyiv’s Linguistic Educational Museum founded in 1992 by the order of the university’s rector. During next sixteen years it was world’s only linguistic museum till the year 2008 when National Museum of Language in the US was opened. In 2013 a new linguistic museum named Mundolingua was established in Paris. After 2014 when the museum in USA was closed and till now it continues to be the only linguistic museum in the world except Linguistic Educational Museum in Ukraine that is functioning. At present times there are several big projects of establishing a comprehensive linguistic museum in different countries. Among them is Planet Word in Washington, Museum der Sprachen der Welt in Berlin, Museum of Language in London. The work upon these projects is in progress and hasn’t reached the stage of completeness. There are also two websites available on the Internet that have the name of museum but does not contain any traces of the exposition content. These are the website of the above mentioned National Museum of Language and Taalmuseum in the Netherlands. Both of these websites are portals for announcements concerning exhibitions, lectures and meetings in different places that are somehow referred to language topics. In this article the structure of the museums content has also been analyzed. Linguistic Educational Museum in Kyiv was established for academic purposes therefore its content has the same structure as the Introductory Linguistics course. At the same time it reveals the principles of the museum exposition author’s Doctor of Science thesis named the Metatheory of Linguisics.

Constrained Substructure Approach to Optimal Strain Energy Analysis

2000 ◽  
Vol 123 (3) ◽  
pp. 340-346 ◽  
Author(s):  
Donald J. Leo ◽  
Eric M. Austin ◽  
Christopher Beattie
Keyword(s):  
Strain Energy ◽  
Optimal Solution ◽  
Structural Elements ◽  
Trial And Error ◽  
Energy Fraction ◽  
Modal Strain Energy ◽  
The Past ◽  
Substructure Approach ◽  
A New Technique ◽  
Damping Treatments

The chief tool for design of viscoelastic-based damping treatments over the past 20 years has been the modal strain energy (MSE) approach. This approach to damping design traditionally has involved a practitioner to vary placement and stiffness of add-on elements using experience and trial and error so as to maximize the add-on element share of system MSE in modes of interest. In this paper we develop a new technique for maximizing strain energy as a function of stiffness for add-on structural elements modeled as rank r perturbations to the original stiffness matrix. The technique is based on a constrained substructure approach allowing us to parameterize strain energy in terms of the eigenvalues of the perturbed structure. An optimality condition is derived that relates the input-output response at the attachment location of the add-on elements to the maximum achievable strain energy. A realizability condition is also derived which indicates whether or not the optimal solution is achievable with passive structural elements. This method has applications in the design of structural treatments for controlling sound and vibration and promises an efficient means of determining the limits of performance of passive structural treatments. An advantage of our approach over existing methods is that the maximum achievable strain energy fraction in the add-on elements is directly computable with the realizability condition then indicating whether the optimal solution is achievable.

scholarly journals A study of the changes in management tasks

2008 ◽  
pp. 39-44
Author(s):  
Ágnes Bilanics
Keyword(s):  
Management Theory ◽  
Production Structure ◽  
Complex Activity ◽  
Management Activity ◽  
Economic Changes ◽  
Face To Face ◽  
The Past ◽  
Market Economic ◽  
The Social ◽  
Special Area

Determining the scope of management is difficult owing to the terminological uncertainty, which can be experienced often. The terms of management theory are interpreted differently not only by the general public but also by the highly recognised specialists, researchers, and instructors of this special area. The reasons for this can be found in historical preliminaries, the different social environment, attitude and approach. The definitions and the content of the terms have been modified and developed in parallel with the social and economic changes (Berde, 2001). The consequences of the economic changes of the past decade have significantly affected the conditions for the operation of management, the management structures, the ranking and importance of management tasks. The differentiating of corporate sizes, the increase in the number of small and medium-sized enterprises, the simplification of the production structure, the decrease in management levels, the strengthening of proprietary positions, and the continuous changing of the market economic environment are all influences that also affect, determine and continuously modify the management tasks.Everyone knows what a manager does. Still, it is not easy to determine what it does all day as his or her work is such a complex activity where the management tasks are present in a complex way, weaved into each other. Nevertheless, the separate management tasks appearing in the management activity can be defined well, can be separated from each other clearly, enabling us to study and analyse each management task separately.Based upon the findings of a face-to-face questionnaire survey, this essay aims to present that, according to the managers, to what extent the judgement of management tasks has changed and to what extent the applied management tasks specialise based upon the extent of relation to the company.

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