Further Analysis of Ration and Growth Relationship of Plaice (Pleuronectes platessa)

1969 ◽  
Vol 26 (12) ◽  
pp. 3237-3241 ◽  
Author(s):  
Samir Zaky Rafail
Keyword(s):  
Maximum Growth ◽  
Growth Efficiency ◽  
Growth Increment ◽  
Mean Value ◽  
Pleuronectes Platessa ◽  
Growth Increments ◽  
Power Equation ◽  
The Mean ◽  
Relationship Of ◽  
Weight Groups

Evidence is given that the average daily rations (R) and fortnightly growth increments (ΔW) of six weight groups of Pleuronectes platessa fed on Mytilus edulis are related as in the power equation ±(ΔW−ΔWm) = ±b(|R–Rm|)B. Rm is the daily ration associated with the growth increment (ΔWm) at maximum growth efficiency; b and B are parameters. The power B has a mean value of about 0.5 and shows significant deviations from the mean especially in the case of smaller fish.

A Statistical Analysis of Ration and Growth Relationship of Plaice (Pleuronectes platessa)

1968 ◽  
Vol 25 (4) ◽  
pp. 717-732 ◽  
Author(s):  
Samir Zaky Rafail
Keyword(s):  
Statistical Analysis ◽  
Maximum Growth ◽  
Growth Efficiency ◽  
Growth Increment ◽  
Square Root ◽  
Daily Ration ◽  
Pleuronectes Platessa ◽  
Ration Level ◽  
Growth Increments ◽  
Relationship Of

Dawes (1930, J. Marine Biol. Assoc, 17: 103 and 877) gave extensive data on average daily rations and fortnightly growth increments of Pleuronectes platessa fed on Mytilus edulis. The data are analyzed here in an attempt to formulate a ration and growth increment relationship. Fortnightly growth increments, Δw, were arranged in eight groups according to eight ranges of fish weights. The growth increments in each group, associated with each average daily ration level (R), gave evidence of the normal distribution. Each range of fish weights was characterized by a certain range of daily rations associated with growth increments having homogeneous variance, as well as by a certain daily ration, Rm, associated with maximum growth efficiency. There was evidence that growth increments, of each range of fish weights, were linearly related with [Formula: see text] such that the value of the square root is positive if R > Rm and negative if R < Rm, i.e., [Formula: see text] where a and b are parameters.

scholarly journals Relationship of Psycho-Traumic Problem (Nightmares) with Students Physical, Mental Health and Their Academic Achievement at Secondary Level Due to War Hazards and U.S. Drone Strikes in North Wazirista

2016 ◽  
Vol I (I) ◽  
pp. 31-37
Author(s):  
Mati Ullah ◽  
Muhammad Saqib Khan ◽  
Noman Ahmad Khan
Keyword(s):  
Academic Achievement ◽  
Pearson Correlation ◽  
Sampling Technique ◽  
Mean Value ◽  
School Students ◽  
Face To Face ◽  
Achievement Data ◽  
Drone Strikes ◽  
The Mean ◽  
Relationship Of

Nightmares badly influence health and learning. Population of the study comprised of all boys and girls of Secondary Schools in NWA whereas (n=403) respondents, 202(50.12%) boys and 201(49.88%) girls were taken as sample from the entire population. Face-to-face questionnaire was used to collect data from respondents through stratified random sampling technique. The key objective of the study was to examine relationship of nightmares with students’ health and their academic achievement. Data was delimited to Secondary School students in NWA. Data was statistically analyzed through SPSS by using Pearson Correlation. The respondents perceived nightmares responsible for students’ poor health and low academic achievement. The Mean value of nightmare was 3.2109, SD, 1.43263, and (p, .000 < 0.05) with negative ‘r’= - .355** which shows negative correlation of nightmares with students’ health and their academic achievement. Results and conclusions were drawn. Recommendations were suggested for future researchers and further improvement in the study.

Growth Increments and Geochemical Variations in the Molluscan Shell

1985 ◽  
Vol 13 ◽  
pp. 72-87 ◽  
Author(s):  
Douglas S. Jones
Keyword(s):  
Shell Growth ◽  
Maximum Growth ◽  
Growth Increment ◽  
Growth Patterns ◽  
Random Disturbance ◽  
Growth Increments ◽  
Molluscan Shell ◽  
External Shell ◽  
Periodic Growth ◽  
Geochemical Variations

Perhaps the one structural feature of the molluscan shell which has historically attracted the most attention from biologists and paleobiologists alike is the banding or growth increment variation associated with so many molluscan species. Such growth patterns are often prominently displayed on the external surfaces of shells and have long been the focus of serious biological and paleontological research (see reviews by Clark, 1974; Lutz and Rhoads, 1980). The usefulness of external shell growth patterns in ecological or paleoecological contexts is limited, however, by both the inability to distinguish true periodic features from random disturbance marks and by the extreme crowding of growth lines near the margins of mature shells. In the last two decades these problems have been surmounted with the recognition of periodic growth patterns within molluscan shells. Internal shell growth patterns are known from all classes of mollusks, but those in the Bivalvia have been studied most extensively. This is a result of the relative ease with which a complete ontogenetic growth record can be obtained by sectioning a shell along the axis of maximum growth (Rhoads and Pannella, 1970). Analogous ontogenetic records are very difficult, if not impossible, to obtain from coiled or spiral shells (e.g., gastropods) using current techniques (Lutz and Rhoads, 1980). This chapter, then, aims to review the major types of internal shell growth patterns described within molluscan shells (mainly bivalves) and to discuss their origin and applications in ecology and paleoecology. Also taken up in this chapter is a brief consideration of geochemical variations (stable oxygen and carbon isotopes and trace and minor elements) within molluscan shells. Physical-chemical, environmental, and physiological influences on shell chemistry are discussed in relation to how biogeochemical variations in the shell may be used to reconstruct paleoenvironmental conditions.

Seasonal growth pattern in the lichen Pseudocyphellaria berberina in north-western Patagonia

2004 ◽  
Vol 36 (6) ◽  
pp. 435-444 ◽  
Author(s):  
Mayra S. CALDIZ
Keyword(s):  
Growth Increment ◽  
Annual Growth ◽  
Seasonal Growth ◽  
Epiphytic Lichen ◽  
Growth Increments ◽  
The Mean ◽  
Individual Trees ◽  
Nothofagus Dombeyi ◽  
North Western ◽  
Annual Growth Increment

Seasonal growth increments (%) were measured in the foliose epiphytic lichen Pseudocyphellaria berberina in north-western Patagonia. Growth was determined by measuring increase in weight (expressed as percentage of the original biomass) in transplanted thalli. Transplants were either hung freely from wooden frames or attached to tree trunks in a Nothofagus dombeyi forest and then weighed every three months between January 2001 and April 2003. The influence on growth increment of treatment, donor thallus, temperature, and absolute and relative humidity was analysed. Mean annual growth increment after two years, in both treatments was 12±1·07% (±SE). Growth increment was greatest in winter and lowest in summer; the mean winter growth increment was 6±0·50%, representing half of the annual growth, whereas most of the remaining growth occurred during both spring and autumn. Growth increments were similar for freely-hanging lichens and for the transplants attached to tree trunks. Individual trees had no consistent effect on growth while the donor thallus had a significant effect in the first season which then diminished, indicating acclimation in the transplants. Initial transplant weight had no influence on final cumulative growth, nor was there any consistent correlation between one season and another in the growth of transplants. Both transplantation methods proved to be useful for experiments on the growth of P. berberina.

scholarly journals Wits Appraisal of a Qatari Male Population: A Comparative Study. Part II

2020 ◽  
Vol 2 (6) ◽  
Author(s):  
Hayder A. Hashim ◽  
Najat Al-Sayed ◽  
Ayah AL-Qaisi
Keyword(s):  
Three Dimensional ◽  
Mean Value ◽  
Cone Beam ◽  
Facial Appearance ◽  
Male Population ◽  
Significant Difference ◽  
The Mean ◽  
Age Range ◽  
Relationship Of ◽  
Gender Specific

Introduction: Cephalometric analysis aims to determine skeletal and dental relationships. The ANB angle, initially suggested by Rediel and applied by Steiner. is the most used angle in establishing the anteroposterior relationship of the mandible to the maxilla. However, limitations to the accuracy of the ANB angle for this purpose have been reported. To avoid these potential sources of inaccuracy a diagnostic tool was introduced by Jenkins and later modified by Jacobson and became known as the “Wits appraisal”. Aims: The aim of this study was to establish the Wits appraisal value in a sample of Qatari males, a group which had not previously been studied in this context, and to compare the findings with those from racially and ethnically differing groups as reported in the literature. Materials and Methods: The sample consisted of 28 lateral cephalometric radiographs of Qatari males with an age range of 15 to 32 years, presenting with a well-balanced facial appearance and an acceptable profile. Results: The mean value of the Wits appraisal for Qatari males in the present study was 0.50 ± 2.96. This differed at a statistically significant level from the mean value in the Jacobson study with no gender significant difference noted. On the other hand, significant differences were found when compared with previous reports on different races. Conclusion: The Wits appraisal value for the Qatari male population studied was 0.5±2.96, a result which is significantly higher than that reported in Jacobson’s study. This study revealed that the Wits appraisal is not ethnicity or gender-specific, and therefore cannot be used to differentiate between different ethnic groups. However, it can find application as an alternative to the ANB angle in the treatment of borderline cases. The application of cone beam computed tomography (CBCT) will enhance the diagnosis and treatment of cases by yielding three-dimensional views.

scholarly journals Optimization of Daylight Factor Distribution Using Standard Deviations Based on Shifting Window Position

Kursor ◽  
2020 ◽  
Vol 10 (3) ◽  
Author(s):  
Yose Rizal ◽  
Imam Robandi ◽  
Eko Mulyanto Yuniarno
Keyword(s):  
Standard Deviation ◽  
Architectural Design ◽  
Mean Value ◽  
Floor Area ◽  
Natural Lighting ◽  
Window Position ◽  
The Mean ◽  
Window Area ◽  
Relationship Of ◽  
The Relationship

Natural lighting is an important factor that affects the comfort of building users. Natural lighting in a room requires a window area of ​​at least 1/6 of the floor area. This study was conducted to obtain the distribution of Daylight Factor (DF) as a natural lighting factor during the day in the room, based on the shift in the position of the window on the wall. The distribution of lighting entering the depth of the room through window openings is a tool to compare the best window position in the spread of illumination with DF calculations based on Sky Component (SC). Shifting the window position will be analyzed by Standard Deviation (S) and Mean (μ) based on the DF distribution. Optimizations of the DF distribution on the window position shifts if it has the largest DF mean value and the smallest DF variant value. The results of the study in a simple room showed that the optimal DF distribution was at the window position in the middle and the mean value was 2.59%. The relationship of shifting window position and DF distribution can be useful for architects to determine the function of a room in architectural design.

A Simulation Model of Lake Trout Growth

1971 ◽  
Vol 28 (6) ◽  
pp. 815-819 ◽  
Author(s):  
S. R. Kerr
Keyword(s):  
Simulation Model ◽  
Growth Model ◽  
Lake Trout ◽  
Growth Efficiency ◽  
Equation System ◽  
Growth Increments ◽  
Predator Size ◽  
Mean Size ◽  
The Mean

Kerr (J. Fish. Res. Bd. Canada 28: 809–814, 1971) described an equation system based upon metabolic constraints and foraging limitations that predicts level of rations and growth efficiency as a function of the availability of the prey resource. An algorithm that extends the equation system to a growth model is described here. With reference to increasing predator size, and to the mean size and abundance of prey, the model computes successive growth increments while holding the equations to the configuration that maximizes the ratio of growth efficiency to rations. When given information on the mean size and density of prey organisms, the model accurately predicts observed patterns of lake trout growth.

Biological and environmental rhythms reflected in molluscan shell growth

1968 ◽  
Vol 42 (S2) ◽  
pp. 64-80 ◽  
Author(s):  
Giorgio Pannella ◽  
Copeland Macclintock
Keyword(s):  
Shell Growth ◽  
Spring Tide ◽  
Growth Increment ◽  
Daily Growth ◽  
Mean Values ◽  
Daily Increments ◽  
Growth Increments ◽  
Tridacna Squamosa ◽  
The Mean ◽  
Daily Growth Increment

Tidal cycles are reflected in daily growth-increment sequences in shells of many Recent and fossil mollusks. Living specimens of the bivalve Mercenaria mercenaria were notched at the growing edge of the shell and planted intertidally in Barnstable Harbor, Massachusetts. Shells from two lots, killed at intervals of 368 and 723 days after planting, show the same number of small growth increments as there were days from notching to killing. Superimposed on daily growth record are effects of winter (thin daily increments) and tides (14-day cycles of thick and thin daily increments). Comparison of Barnstable tide record with the first year's growth shows that, for each 14-day cycle, thin daily increments form during neap tides and thicker daily increments form during spring tides. Although tidal patterns are present in subtidal Mercenaria shells, they are rarely as pronounced as in intertidal ones. Spawning patterns differ from winter patterns; they are expressed in the shell by an interruption of regular deposition followed by a series of thin daily increments. Continuous sequences of bidaily patterns, one thick daily increment followed by a relatively thin one, are common in M. mercenaria.The clearest 14-day cycles of deposition were seen in shells of the bivalve Tridacna squamosa. Each daily neap-tide increment is a simple layer consisting of a dark and light zone. Each daily spring-tide increment is a complex layer consisting of two light-dark alternations separated by a depositional break that is more pronounced than the breaks delimiting daily intervals. Preliminary results of growth-increment counts in fossils show a generally decreasing trend of the mean values of days per lunar month toward the Recent. The Pennsylvanian value is 30.07 ± 0.08, a figure that is in general agreement with those of Scrutton (1964), who counted 30.59 days per month on Devonian corals, and Barker (1966), who reported more than 30 days per month in Pennsylvanian bivalves.

Psychometric Properties of a Stress Questionnaire and its Use in the Workplace

1999 ◽  
Vol 85 (1) ◽  
pp. 131-137
Author(s):  
Tomoyuki Kawada
Keyword(s):  
Reliability And Validity ◽  
Mean Value ◽  
Analysis Of Covariance ◽  
Significant Difference ◽  
Principal Axis Factor Analysis ◽  
The Mean ◽  
Relationship Of ◽  
The Relationship ◽  
A Company ◽  
Self Administered Questionnaire

This study focused on the reliability and validity of the stress questionnaire and the relationship of responses to types of work. This self-administered questionnaire was distributed to all 799 employees of a company. 792 responded. There are 21 items with yes-no responses for which the score was the sum of assigned weights. Types of work represented manager, technical manufacturer, clerk, manufacturer, and sales. From a principal axis factor analysis three factors were extracted for men and for women, respectively. There was a significant difference in mean score among five groups of workplace positions by Kruskal-Wallis one-way analysis of covariance ( p = .04). The mean value for manager was not significant but was relatively lower than those of the other positions, suggesting that being a manager was less stressful. Confirmation with the testing of an independent sample is also needed to validate the consistency of the association.

Effect of Individual Variability on the von Bertalanffy Growth Equation

1980 ◽  
Vol 37 (2) ◽  
pp. 241-247 ◽  
Author(s):  
K. J. Sainsbury
Keyword(s):  
Growth Models ◽  
Growth Increment ◽  
Mean Value ◽  
Individual Variability ◽  
Age And Growth ◽  
Growth Equation ◽  
Von Bertalanffy ◽  
Von Bertalanffy Model ◽  
The Mean ◽  
Von Bertalanffy Growth Equation

The growth in length of a group of animals is examined. Each animal is assumed to grow according to the von Bertalanffy model with fixed parameters, but these parameters are allowed to differ between individuals. Equations governing the mean and variance of length at given age and growth increment at given length are provided, and their implications discussed. Results indicate that the traditional growth equation is likely to result in an underestimate of the mean value of K when either length at age or growth increment data are analyzed. This problem does not appear serious when using length at age data. However, the problems of interpretation are more serious in the case of growth increment data where serious overestimates of the reconstructed mean length at age can result. A thorough analysis of growth cannot be made for a population exhibiting individual variability in L∞ and K from growth increment data alone. In particular a nonlinear relationship between growth increment and initial length does not necessarily imply that the von Bertalanffy model is inappropriate to the species in question. A topic urgently in need of examination is the form of the joint distribution of K and L∞ in animal populations.Key words: von Bertalanffy, growth models

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