scholarly journals Analysis of possible reasons of impulses repetition frequency choice made by marine mammals during different forms of activity

2021 ◽  
Vol 0 (2) ◽  
pp. 52-57
Author(s):  
S.E. Karpichenko
Keyword(s):  
Marine Mammals ◽  
Repetition Frequency ◽  
Definition Of

In this article are analyzed scientific reports in a field of marine mammals echolocations, including data of their sounding impulses with repetition frequency significantly more, that need for definition of distance to objects of hunting. The interrelation between the increased repetition frequencies of impulses and types of subjects of hunting is established. Following frequencies of such impulses types and of related objects of hunting are presented in a table view.

Cetacean culture: Humans of the sea?

2001 ◽  
Vol 24 (2) ◽  
pp. 358-359 ◽  
Author(s):  
Peter L. Tyack
Keyword(s):  
Social Learning ◽  
Marine Mammals ◽  
Genetic Factors ◽  
Data Gaps ◽  
Standards Of Evidence ◽  
Definition Of ◽  
Rule Out

Rendell and Whitehead adopt a weak definition of culture to allow low standards of evidence for marine mammals, but they do not adequately rule out genetic factors or individual versus social learning. They then use these low standards to argue that some whales have unique cultures only matched by humans. It would have been more helpful to specify data gaps and suggest critical tests.

scholarly journals Ecosystem-Based Fisheries Management, Commercial Fisheries, Marine Mammals and the 2001 Reykjavik Declaration in the Context of International Law

2002 ◽  
Vol 17 (4) ◽  
pp. 561-595 ◽  
Author(s):  
Erik Jaap Molenaar
Keyword(s):  
Fisheries Management ◽  
Marine Mammals ◽  
Legal Status ◽  
Marine Ecosystem ◽  
Commercial Fisheries ◽  
Positive Effects ◽  
Legal Constraints ◽  
Definition Of ◽  
Ecosystem Based Fisheries Management

AbstractThe current global crisis in marine capture fisheries contrasts sharply with the recovery of some stocks of marine mammals. Eventually this will have to lead to a re-evaluation of the preferential treatment that marine mammals now often enjoy. The widening support for ecosystem-based fisheries management (EBFM) and the growing insight in the interactions between marine mammals and commercial fisheries are expected to influence this evaluation. This article examines the role of marine mammals in the ecosystem with special emphasis on predation on commercial fisheries. Ample attention is devoted to the definition of EBFM, its legal status and issues of implementation. The 2001 Reykjavik Declaration on Responsible Fisheries in the Marine Ecosystem is used for illustration. One of the conclusions is that sufficient scientific research is required to substantiate positive effects that pre-emptive catches of marine mammals would have for (recovering) commercial fisheries. The regulatory objectives and international legal constraints relevant to marine mammals are moreover addressed to determine if the exploitation of marine mammals could be obligatory or "necessary".

Marine Sound Pollution: Does It Merit Concern?

2003 ◽  
Vol 37 (4) ◽  
pp. 66-77 ◽  
Author(s):  
Robert J. Hofman
Keyword(s):  
Marine Mammal ◽  
Marine Mammals ◽  
Oil And Gas ◽  
Low Frequency ◽  
Anthropogenic Sources ◽  
Fiscal Year ◽  
National Defense ◽  
Oil And Gas Development ◽  
The Bahamas ◽  
Definition Of

The possible effects on marine mammals and other marine organisms of sound from human (anthropogenic) sources have become subjects of increasing concern and controversy. In the late 1970s and 1980s, the sources of principal concern were seismic profiling, drilling, and related activities associated with offshore oil and gas development. In the last decade, much of the focus has shifted to activities conducted or supported by the U.S. Navy, most notably the Acoustic Thermometry of Ocean Climate Program, ship-shock tests, development and proposed use of low frequency active sonar to detect new classes of quiet submarines, and the stranding of beaked whales and other cetaceans in the Bahamas in March 2000 coincident with antisubmarine exercises involving use of mid-frequency tactical sonars. There has been substantial controversy concerning the possible impacts of these activities, and a number of law suits seeking to stop or restrict them. The Navy believes that the concerns are unwarranted and that the law suits have impeded its ability to meet its national defense responsibilities. Congress agreed and in the National Defense Authorization Act for Fiscal Year 2004 (Public Law 108-87) made two substantial changes to the Marine Mammal Protection Act (MMPA): (1) it authorized the Secretary of Defense to exempt military readiness activities from the provisions of the MMPA governing the incidental taking of marine mammals; and (2) it added to the Act separate definitions of harassment to apply to such activities. These and other proposed changes to the MMPA could undermine the unique, precautionary or risk-averse philosophy of the Act. An alternative, two-step approach, advocated in this paper, would be to (a) revise the definition of harassment to clearly differentiate types and levels of behavioral disturbance likely to have, and not to have, biologically significant effects; and (b) add a general authorization for all incidental taking expected to have biologically insignificant effects, similar to the general authorization for marine mammal research expected to have biologically insignificant effects added to the MMPA in 1994.

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.

2.2. Working Group 2: Conceptual Definitions of Reference Coordinate Systems for Earth Dynamics

1975 ◽  
Vol 26 ◽  
pp. 21-26
Keyword(s):  
Coordinate System ◽  
Working Group ◽  
General Character ◽  
Coordinate Systems ◽  
Reference Coordinate System ◽  
Group 2 ◽  
Definition Of ◽  
Earth Dynamics

An ideal definition of a reference coordinate system should meet the following general requirements:1. It should be as conceptually simple as possible, so its philosophy is well understood by the users.2. It should imply as few physical assumptions as possible. Wherever they are necessary, such assumptions should be of a very general character and, in particular, they should not be dependent upon astronomical and geophysical detailed theories.3. It should suggest a materialization that is dynamically stable and is accessible to observations with the required accuracy.

Symbiotic Stars at Optical, Infrared and Radio Wavelengths

1979 ◽  
Vol 46 ◽  
pp. 125-149 ◽  
Author(s):  
David A. Allen
Keyword(s):  
Temperature Regime ◽  
Type Star ◽  
Stellar Systems ◽  
Symbiotic Stars ◽  
Lower Excitation ◽  
Definition Of ◽  
Original Type

No paper of this nature should begin without a definition of symbiotic stars. It was Paul Merrill who, borrowing on his botanical background, coined the termsymbioticto describe apparently single stellar systems which combine the TiO absorption of M giants (temperature regime ≲ 3500 K) with He II emission (temperature regime ≳ 100,000 K). He and Milton Humason had in 1932 first drawn attention to three such stars: AX Per, CI Cyg and RW Hya. At the conclusion of the Mount Wilson Ha emission survey nearly a dozen had been identified, and Z And had become their type star. The numbers slowly grew, as much because the definition widened to include lower-excitation specimens as because new examples of the original type were found. In 1970 Wackerling listed 30; this was the last compendium of symbiotic stars published.

Immunoferritin localization of intracellular antigens in positively stained frozen sections

1978 ◽  
Vol 36 (2) ◽  
pp. 168-169
Author(s):  
K. T. Tokuyasu
Keyword(s):  
Surface Tension ◽  
Water Surface ◽  
Thin Layers ◽  
The Other ◽  
Positive Staining ◽  
Frozen Sections ◽  
The Past ◽  
Ultrathin Frozen Sections ◽  
Definition Of

During the past investigations of immunoferritin localization of intracellular antigens in ultrathin frozen sections, we found that the degree of negative staining required to delineate u1trastructural details was often too dense for the recognition of ferritin particles. The quality of positive staining of ultrathin frozen sections, on the other hand, has generally been far inferior to that attainable in conventional plastic embedded sections, particularly in the definition of membranes. As we discussed before, a main cause of this difficulty seemed to be the vulnerability of frozen sections to the damaging effects of air-water surface tension at the time of drying of the sections.Indeed, we found that the quality of positive staining is greatly improved when positively stained frozen sections are protected against the effects of surface tension by embedding them in thin layers of mechanically stable materials at the time of drying (unpublished).

Initial Polymerization Sites Indicated During Mitochondrial Oxidation of Diaminobenzidine after Toluene Treatment

1977 ◽  
Vol 35 ◽  
pp. 408-409
Author(s):  
W. A. Shannon ◽  
M. A. Matlib
Keyword(s):  
Membrane Permeability ◽  
Cytochrome Oxidase ◽  
Rat Liver ◽  
Precise Definition ◽  
Cytochemical Localization ◽  
Oxidative Reaction ◽  
Mitochondrial Oxidation ◽  
Definition Of ◽  
Exogenous Substrates

Numerous studies have dealt with the cytochemical localization of cytochrome oxidase via cytochrome c. More recent studies have dealt with indicating initial foci of this reaction by altering incubation pH (1) or postosmication procedure (2,3). The following study is an attempt to locate such foci by altering membrane permeability. It is thought that such alterations within the limits of maintaining morphological integrity of the membranes will ease the entry of exogenous substrates resulting in a much quicker oxidation and subsequently a more precise definition of the oxidative reaction.The diaminobenzidine (DAB) method of Seligman et al. (4) was used. Minced pieces of rat liver were incubated for 1 hr following toluene treatment (5,6). Experimental variations consisted of incubating fixed or unfixed tissues treated with toluene and unfixed tissues treated with toluene and subsequently fixed.

Application of Scanning Electron Microscopy to Medical Research

1969 ◽  
Vol 27 ◽  
pp. 12-13
Author(s):  
J. D. Hutchison
Keyword(s):  
Electron Microscopy ◽  
Electron Microscope ◽  
Medical Research ◽  
Prosthetic Heart Valve ◽  
School Of Medicine ◽  
Transmission Electron ◽  
Definition Of ◽  
Mechanism Of Failure ◽  
The Brain ◽  
Scanning Electron

When the transmission electron microscope was commercially introduced a few years ago, it was heralded as one of the most significant aids to medical research of the century. It continues to occupy that niche; however, the scanning electron microscope is gaining rapidly in relative importance as it fills the gap between conventional optical microscopy and transmission electron microscopy.IBM Boulder is conducting three major programs in cooperation with the Colorado School of Medicine. These are the study of the mechanism of failure of the prosthetic heart valve, the study of the ultrastructure of lung tissue, and the definition of the function of the cilia of the ventricular ependyma of the brain.

Selection and Preparation of Specific Tissue Regions For Tem Using Large Epoxy-Embedded Blocks

1973 ◽  
Vol 31 ◽  
pp. 324-325 ◽  
Author(s):  
P. M. Lowrie ◽  
W. S. Tyler
Keyword(s):  
Electron Microscopy ◽  
Anatomical Structures ◽  
Ultrastructural Studies ◽  
Transmission Electron ◽  
Microscopic Evaluation ◽  
Embedded Blocks ◽  
Specific Tissue ◽  
Definition Of ◽  
Areas Of Interest ◽  
Selection Of

The importance of examining stained 1 to 2μ plastic sections by light microscopy has long been recognized, both for increased definition of many histologic features and for selection of specimen samples to be used in ultrastructural studies. Selection of specimens with specific orien ation relative to anatomical structures becomes of critical importance in ultrastructural investigations of organs such as the lung. The uantity of blocks necessary to locate special areas of interest by random sampling is large, however, and the method is lacking in precision. Several methods have been described for selection of specific areas for electron microscopy using light microscopic evaluation of paraffin, epoxy-infiltrated, or epoxy-embedded large blocks from which thick sections were cut. Selected areas from these thick sections were subsequently removed and re-embedded or attached to blank precasted blocks and resectioned for transmission electron microscopy (TEM).

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