scholarly journals The Reproductive Biology of Female Atlantic Herring in U.S. Waters: Validating Classification Schemes for Assessing the Importance of Spring and Skipped Spawning

2019 ◽  
Vol 11 (6) ◽  
pp. 487-505 ◽  
Author(s):  
Mark J. Wuenschel ◽  
Jonathan J. Deroba
Keyword(s):  
Reproductive Biology ◽  
Atlantic Herring ◽  
Classification Schemes ◽  
Skipped Spawning

Do capital breeders like Atlantic herring (Clupea harengus) exhibit sensitive periods of nutritional control on ovary development and fecundity regulation?

2010 ◽  
Vol 67 (1) ◽  
pp. 16-27 ◽  
Author(s):  
James Kennedy ◽  
Jon Egil Skjæraasen ◽  
Richard D.M. Nash ◽  
Anders Thorsen ◽  
Aril Slotte ◽  
...  
Keyword(s):  
Food Availability ◽  
Clupea Harengus ◽  
Sensitive Period ◽  
Ovary Development ◽  
Atlantic Herring ◽  
Energy Reserves ◽  
Skipped Spawning ◽  
Capital Breeder ◽  
Low K ◽  
Ovary Maturation

A laboratory study was undertaken to investigate whether Northeast Atlantic herring ( Clupea harengus ), i.e., Norwegian spring-spawning herring, exhibit a “sensitive period” during the feeding season in which ovary development is particularly susceptible to food availability and (or) energy reserves. Groups of herring received similar amounts of food over the restricted summer – early autumn feeding season but the food availability was varied temporally between groups. The herring, an extreme capital breeder, did not exhibit a sensitive period, as there was no difference in fecundity or ovary maturation between groups. However, individuals that did not reach a Fulton’s condition factor (K) above 0.70 during the feeding season were less likely to begin ovary maturation. Those below this threshold showing ovary development began later and had a higher intensity of atresia than fish in better condition. To maximize fecundity, females recruited significantly more oocytes than they could support through to spawning, thus the oocytes were subsequently down-regulated. Some would have skipped spawning in the coming spawning season; these fish had a very low K. Taken together, this study demonstrates that this capital breeder has developed a suite of reproductive strategies to synchronize the production of the highest number of eggs energetically possible.

Fine structure and possible functions of the hermaphrodite duct of some pulmonate snails (Mollusca: Gastropoda)

1990 ◽  
Vol 48 (3) ◽  
pp. 68-69
Author(s):  
Alan N. Hodgson
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Fine Structure ◽  
Seminal Vesicle ◽  
Reproductive Biology ◽  
Light Microscope ◽  
Light Microscope Level ◽  
Transmission Electron ◽  
Standard Techniques

The hermaphrodite duct of pulmonate snails connects the ovotestis to the fertilization pouch. The duct is typically divided into three zones; aproximal duct which leaves the ovotestis, the middle duct (seminal vesicle) and the distal ovotestis duct. The seminal vesicle forms the major portion of the duct and is thought to store sperm prior to copulation. In addition the duct may also play a role in sperm maturation and degredation. Although the structure of the seminal vesicle has been described for a number of snails at the light microscope level there appear to be only two descriptions of the ultrastructure of this tissue. Clearly if the role of the hermaphrodite duct in the reproductive biology of pulmonatesis to be understood, knowledge of its fine structure is required.Hermaphrodite ducts, both containing and lacking sperm, of species of the terrestrial pulmonate genera Sphincterochila, Levantina, and Helix and the marine pulmonate genus Siphonaria were prepared for transmission electron microscopy by standard techniques.

PHASAL REALIZATIONS IN CLASSROOM DISCOURSE A Systemic-Functional Analysis

TABULARASA ◽  
2014 ◽  
Vol 11 (2) ◽  
Author(s):  
Lasyuli Simbolon
Keyword(s):  
Functional Analysis ◽  
Strong Evidence ◽  
Classroom Discourse ◽  
Social Values ◽  
Classroom Interactions ◽  
Classification Schemes ◽  
Complementary Method ◽  
Academic Knowledge ◽  
Primary Instrument

This article examines the phasal realizations characteristic of the classroom discourse. The data are collected by means of audio-visual recordings and transcriptions, and they are analyzed by employing a complementary method of analysis of Young’s model. The primary instrument of this study is the researcher herself, whereas the secondary instruments are (1) classification schemes of the semiotic aspect in focus, (2) data sheets that contain 4 classroom discourse-in-texts, and (3) notes on each classroom discourse-in-text. The findings reveal that the CD-in-text as a whole is typically realized and characterized by the following: (1) Substantiation (SU) as the most prominent macro-function and the Conclusion (CO) as the least prominent, (2) the Interchange (IC) as the most prominent micro-function and the Apology (AP) as the least prominent. Based on the main findings, there is strong evidence to suggest that the ‘semiotic behavior’ of the CD-in-text as a whole is motivated by the goal-oriented need, and the goal to achieve has tended to be more academic-oriented than social-oriented. In this, the teachers as the primary speakers of the classroom interactions have tended to focus on the transformation of intellectual values (academic knowledge/skills) with the least social values involved therein. The most prominently occurring SU macro-function and IC micro-function are clear indicators of this endeavor. The scope and the objectives of this study have been delimited to investigate CD phenomena at the levels of phase and sub-phase.

HYBRID CLASSIFICATION SCHEMES FOR HEART MURMUR DETECTION TO ASSIST PHONOCARDIOGRAM BASED SIGNAL ACQUISITION

2017 ◽  
Vol 13 (9) ◽  
pp. 6480-6488 ◽  
Author(s):  
A.D. Jeyarani ◽  
Reena Daphne ◽  
Solomon Roach
Keyword(s):  
Neural Network ◽  
Signal Acquisition ◽  
Heart Murmur ◽  
Classification Techniques ◽  
Classification Schemes ◽  
Neural Network Classification ◽  
Nonlinear Classification ◽  
Processing Step ◽  
System Characterization ◽  
Hybrid Classification

The main contribution of this paper has been to introduce nonlinear classification techniques to extract more information from the PCG signal. Especially, Artificial Neural Network classification techniques have been used to reconstruct the underlying system’s state space based on the measured PCG signal. This processing step provides a geometrical interpretation of the dynamics of the signal, whose structure can be utilized for both system characterization and classification as well as for signal processing tasks such as detection and prediction.

Structure, Logic, and Semantics in ad hoc Classification Schemes Applied to Web-Based Libraries in the Field of Education

2013 ◽  
Author(s):  
Michèle Hudon ◽  
Sabine Mas ◽  
Dominique Gazo
Keyword(s):  
Ad Hoc ◽  
Knowledge Organization ◽  
Theoretical Research ◽  
Web Based ◽  
Classification Schemes ◽  
Research Traditions ◽  
Local Perspectives

This project focuses on a sample of six Web-based libraries in the field of Education. Our analysis explores structural, logic and semantic dimensions, supported by theoretical research in classification and in the area of personal document spaces organization, and by findings of previous analyses of Web directory structures. Our findings expand our understanding of how Web-based resources in education are organized, helping us determine whether categorization schemes and keywords reflect anything else than local perspectives and systems, while bringing together two research traditions issued respectively from knowledge organization and from document and records management.Ce projet est axé sur un échantillon de six bibliothèques sur le Web dans le domaine de l’éducation. Notre analyse explore les dimensions structurelles, logiques et sémantiques, corroborée par la recherche théorique en classification et dans le domaine de l’organisation des espaces documentaires personnels, et par les résultats d’analyses préliminaires de la structure des répertoires Web. Nos résultats développent notre compréhension sur la manière dont les ressources Web en éducation sont organisées, nous aidant ainsi à déterminer… 

The Reproductive Biology of Haddock (Mellanogrammus aeglefinus) at the Rockall Bank

2009 ◽  
Vol 40 ◽  
pp. 59-73 ◽  
Author(s):  
E A Filina ◽  
V N Khlivnoy ◽  
V I Vinnichenko
Keyword(s):  
Reproductive Biology
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