On the definition of valence of functional groups in molecules

1996 ◽  
Vol 93 (3) ◽  
pp. 165-176 ◽  
Author(s):  
Robert Ponec ◽  
Matthias Krack ◽  
Karl Jug
Keyword(s):  
Functional Groups ◽  
Definition Of

scholarly journals Recurrent interactions can explain the variance in single trial responses

2019 ◽  
Author(s):  
Subhodh Kotekal ◽  
Jason N. MacLean
Keyword(s):  
Functional Groups ◽  
Cortical Neurons ◽  
Sensory Information ◽  
Operational Definition ◽  
Single Trial ◽  
Running Speed ◽  
Local Correlations ◽  
Sensory Encoding ◽  
Definition Of ◽  
Visual Cortical

1.AbstractTo develop a complete description of sensory encoding, it is necessary to account for trial-to-trial variability in cortical neurons. Using a generalized linear model with terms corresponding to the visual stimulus, mouse running speed, and experimentally measured neuronal correlations, we modeled short term dynamics of L2/3 murine visual cortical neurons to evaluate the relative importance of each factor to neuronal variability within single trials. We find single trial predictions improve most when conditioning on the experimentally measured local correlations in comparison to predictions based on the stimulus or running speed. Specifically, accurate predictions are driven by positively co-varying and synchronously active functional groups of neurons. Including functional groups in the model enhances decoding accuracy of sensory information compared to a model that assumes neuronal independence. Functional groups, in encoding and decoding frameworks, provide an operational definition of Hebbian assemblies in which local correlations largely explain neuronal responses on individual trials.

The soft-sediment benthos in the ecosystem

2009 ◽  
Author(s):  
John S. Gray ◽  
Michael Elliott
Keyword(s):  
Functional Groups ◽  
Morphological Characteristics ◽  
Feeding Guilds ◽  
Benthic Species ◽  
Feeding Mode ◽  
Complex Interactions ◽  
Filter Feeders ◽  
Definition Of ◽  
Modes Of Life ◽  
Deposit Feeding

The benthos does not, of course, live in isolation from other parts of the ecosystem. Here we consider the roles that the benthos plays in the system and how the complex interactions that are found can be modelled using ecosystem models. First, we examine methods that allow us to establish food webs based not only on examining each species in the field and in laboratory feeding studies, but also using stable isotopes of carbon and nitrogen to ascertain the likely feeding mode of a species. It is relatively easy to determine the mode of feeding of some benthic organisms (see for example the excellent review of Fauchald and Jumars 1979, although this is now slightly dated and requires revision). Polychaetes have characteristic feeding structures, so one can determine from their morphology whether they are filter feeders, deposit feeders, or predators. Bivalves show similar morphological characteristics and it is easy to determine whether they are deposit or filter feeders. Some polychaetes have large jaws, e.g. the nereids, and one might assume that they are predators. Yet when Nereis vexillosa was studied in detail (Woodin 1977), it was found that it attached pieces of algae to its tube, which grew and were used for food, so-called ´gardening´. Nereids also are able to filter feed by creating a mucous bag and pumping water through their burrows, which filters the water; the mucous bag is then consumed. More recently, studies have shown varied and possibly opportunistic feeding by different benthic species; for example Christensen et al. (2000) showed how the suspension- and deposit-feeding abilities of nereids influenced sediment nutrient fluxes. These studies show that it is perhaps not so straightforward as once thought to interpret feeding mode simply from morphological features. The definition of functional groups and feeding guilds is increasingly used to help explain and interpret ecological functioning (e.g. Elliott et al. 2007 discuss the rationale behind functional groups). The eminent and immensely experienced benthic biologist Tom Pearson (2001) shows in detail that while the concept of functional groups gives us a greater understanding of the benthos, the idea is criticized by some as we do not have sufficient information about feeding types and modes of life of many benthic species.

Methods for the comparison of fulvic acid samples: the effects of origin and concentration on acidic properties

1978 ◽  
Vol 56 (9) ◽  
pp. 1196-1201 ◽  
Author(s):  
R. Douglas Burch ◽  
Cooper H. Langford ◽  
Donald S. Gamble
Keyword(s):  
Fulvic Acid ◽  
Functional Groups ◽  
Weighted Average ◽  
Chemical Characteristics ◽  
Acid Solutions ◽  
Concentration Change ◽  
Acidic Properties ◽  
General Chemical ◽  
Equilibrium Function ◽  
Definition Of

The principles according to which the acidic properties of fulvic acid solutions should be compared are demonstrated. An equilibrium function defined and measured for any mixture, including fulvic acid functional groups, will be a weighted average. A concentration change will generally affect this average by changing the relative values of the statistical weights. Concentration corrections are therefore required for the comparison of two fulvic acid solutions. A Chernozem Ah fulvic acid and the previously described Armadale fulvic acid Batch FA1 were examined in this way. They were found to have the same general chemical characteristics, but with somewhat different numerical values. The implications of these results for the definition of fulvic acid are considered.

scholarly journals functionInk: An efficient method to detect functional groups in multidimensional networks reveals the hidden structure of ecological communities

2019 ◽  
Author(s):  
Alberto Pascual-García ◽  
Thomas Bell
Keyword(s):  
Functional Groups ◽  
Trophic Levels ◽  
List Type ◽  
Ecological Communities ◽  
Computationally Efficient ◽  
Qualitative Properties ◽  
Functional Roles ◽  
External Data ◽  
New Information ◽  
Definition Of

AbstractComplex networks have been useful to link experimental data with mechanistic models, and have become widely used across many scientific disciplines. Recently, the increasing amount and complexity of data, particularly in biology, has prompted the development of multidimensional networks, where dimensions reflect the multiple qualitative properties of nodes, links, or both. As a consequence, traditional quantities computed in single dimensional networks should be adapted to incorporate this new information. A particularly important problem is the detection of communities, namely sets of nodes sharing certain properties, which reduces the complexity of the networks, hence facilitating its interpretation.In this work, we propose an operative definition of “function” for the nodes in multidimensional networks, and we exploit this definition to show that it is possible to detect two types of communities: i) modules, which are communities more densely connected within their members than with nodes belonging to other communities, and ii) guilds, which are sets of nodes connected with the same neighbours, even if they are not connected themselves. We provide two quantities to optimally detect both types of communities, whose relative values reflect their importance in the network.The flexibility of the method allowed us to analyze different ecological examples encompassing mutualistic, trophic and microbial networks. We showed that by considering both metrics we were able to obtain deeper ecological insights about how these different ecological communities were structured. The method mapped pools of species with properties that were known in advance, such as plants and pollinators. Other types of communities found, when contrasted with external data, turned out to be ecologically meaningful, allowing us to identify species with important functional roles or the influence of environmental variables. Furthermore, we found the method was sensitive to community-level topological properties like the nestedness.In ecology there is often a need to identify groupings including trophic levels, guilds, functional groups, or ecotypes.The method is therefore important in providing an objective means of distinguishing modules and guilds. The method we developed, functionInk (functional linkage), is computationally efficient at handling large multidimensional networks since it does not require optimization procedures or tests of robustness. The method is available at: HTTPS://GITHUB.COM/APASCUALGARCIA/FUNCTIONINK.

scholarly journals CAPABILITY OF CIVIL PROTECTION

2020 ◽  
Vol 1 (1) ◽  
pp. 4-13
Author(s):  
L Кalynenko ◽  
A Sliusar ◽  
A Fomin ◽  
A Borysova
Keyword(s):  
Functional Groups ◽  
Public Safety ◽  
Armed Forces ◽  
Civil Defense ◽  
Civil Protection ◽  
Institute Of Public Administration ◽  
Functional Capabilities ◽  
New Concepts ◽  
Protection Capability ◽  
Definition Of

The specialists of the Institute of Public Administration and Research in Civil Protection are tasked to actually find approaches to a completely new direction in the field of civil protection - assessing the capabilities of civil protection and preparing recommendations on how to implement these approaches.  This requires significant work on the definition of new terms and concepts, the formulation of the main functional capabilities of civil protection and their features, the study of properties and requirements for capabilities, their systematization by functional purpose justification of the main functional groups. The purpose of the article is to acquaint the interested audience with new concepts and approaches for the field of civil protection.  In order to define the concept of "civil protection capability", the authors have worked out a number of laws and regulations on civil defense and national security and defense, as well as foreign documents, including NATO, and materials on defense strategic planning based on capabilities of the armed forces. To assess current and future threats to public safety, the population and the territory from emergencies, to develop an effective model for combating crimes against public safety and other illegal encroachments, it is necessary to determine the state of the unified state civil defense system, functional and territorial subsystems and other civil defense forces. for possible emergencies, taking into account potential threats. The article defines the concept of " capability analysis of functional and territorial subsystems of a single state civil protection system, civil protection forces", "capability requirements", "basic components of capabilities", "functional groups (integrated categories) of capabilities", "catalog of civil protection capabilities" etc.   Key words: "capability" concepts, security and defense capabilities, civil defense capabilities, basic capability components, functional groups (integrated categories) of capabilities, capability catalog, civil defense overview.

Introductory paper

1966 ◽  
Vol 24 ◽  
pp. 3-5
Author(s):  
W. W. Morgan
Keyword(s):  
Line Intensity ◽  
Classification Scheme ◽  
Two Dimensional ◽  
Spectral Classification ◽  
Dimensional Array ◽  
Rr Lyrae ◽  
Metallic Line ◽  
Introductory Paper ◽  
Parameter Varying ◽  
Definition Of

1. The definition of “normal” stars in spectral classification changes with time; at the time of the publication of theYerkes Spectral Atlasthe term “normal” was applied to stars whose spectra could be fitted smoothly into a two-dimensional array. Thus, at that time, weak-lined spectra (RR Lyrae and HD 140283) would have been considered peculiar. At the present time we would tend to classify such spectra as “normal”—in a more complicated classification scheme which would have a parameter varying with metallic-line intensity within a specific spectral subdivision.

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