Spatio-temporal spawning patterns of two riverine populations of the threatened Macquarie perch (Macquaria australasica)

2016 ◽  
Vol 67 (11) ◽  
pp. 1762 ◽  
Author(s):  
Zeb Tonkin ◽  
Joanne Kearns ◽  
Justin O'Mahony ◽  
John Mahoney
Keyword(s):  
Positive Association ◽  
Temporal Constraints ◽  
Spawning Habitat ◽  
Management Options ◽  
Strong Positive Association ◽  
Spatio Temporal ◽  
Study Sites ◽  
Transfer Of Information ◽  
Riverine Fish ◽  
Yarra River

Understanding species-reproduction dynamics is vital for the management of riverine fish. Information on the spawning ecology of the endangered Australian Macquarie perch (Macquaria australasica) is based largely on data gathered from lacustrine populations, with uncertainty on the applicability such data has for managing riverine populations. The current study presents a first description of spawning patterns of two riverine populations of Macquarie perch in Victoria, Australia, using egg counts recorded across multiple sites and periods within the species core spawning window. Spawning intensity was highly variable between study sites, with 96 and 82% of eggs collected from a single site in the King Parrot Creek and Yarra River respectively. We also found a strong positive association between spawning and water temperature. Our results provide an important account of spatio-temporal spawning patterns of riverine Macquarie perch populations and lend some support for the transfer of information from lacustrine populations (as demonstrated by spawning habitat and temperature association). Although the spatial and temporal constraints of the present study must be considered, the results provide opportunity for further testing of the environmental effects, and management options aimed at enhancing spawning of this endangered species.

scholarly journals Factors Affecting the Rate of Fuel Consumption in Aircrafts

2021 ◽  
Vol 13 (14) ◽  
pp. 8066
Author(s):  
Thowayeb H. Hassan ◽  
Abu Elnasr E. Sobaih ◽  
Amany E. Salem
Keyword(s):  
Fuel Consumption ◽  
Positive Association ◽  
Pollutant Emissions ◽  
Aviation Industry ◽  
Factors Affecting ◽  
Fuel Flow ◽  
Homogeneity Of Variance ◽  
Strong Positive Association ◽  
Ground Distance ◽  
The Cost

The cost of fuel and its availability are among the most major concerns for aircrafts and the aviation industry overall. Environmental difficulties with chemical pollutant emissions emitted by aviation machines are also connected to fuel consumption. As a result, it is crucial to examine factors that affect the overall fuel usage and consumption in the airport-based aviation industry. Several variables were investigated related to the total fuel consumed, such as dry operating weight (DOW) (KG), zero-fuel weight (ZFW), take-off weight (TOW), air distance (AIR DIST) (KM), and ground distance (GDN DIST). Analysis of the correlation between total fuel consumed as well as the extra fuel and selected variables was conducted. The results showed that the most positively associated factors with the total used fuel were the air distance (r2 = 0.86, p < 0.01), ground distance (r2 = 0.78, p < 0.01), TOW (r2 = 0.68, p < 0.01), and flight time (r2 = 0.68, p < 0.01). There was also a strong positive association between the average fuel flow (FF) and actual TOW (r2 = 0.74, p < 0.01) as well as ZFW (r2 = 0.61, p < 0.01). The generalized linear model (GLM) was utilized to assess the predictions of total energy usage after evaluating important outliers, stability of the homogeneity of variance, and the normalization of the parameter estimation. The results of multiple linear regression revealed that the most significant predictors of the total consumed fuel were the actual ZFW (p < 0.01), actual TOW (p < 0.01), and actual average FF (p < 0.05). The results interestingly confirmed that wind speed has some consequences and effects on arrival fuel usage. The result reflects that thermal and hydrodynamic economies impact on the flying fuel economy. The research has various implications for both scholars and practitioners of aviation industry.

Hypertension, Cerebrovascular Disease and Stomach Cancer: Is the Salt Hypothesis True?

1981 ◽  
Vol 61 (s7) ◽  
pp. 369s-371s ◽  
Author(s):  
Paul K. Whelton ◽  
Peter Goldblatt
Keyword(s):  
Stomach Cancer ◽  
Death Certificate ◽  
Positive Association ◽  
Special Relationship ◽  
Death Rates ◽  
Disease Associations ◽  
Strong Positive Association ◽  
Diagnostic Concordance ◽  
The Relationship ◽  
Unique Relationship

1. Analysis of age-adjusted death rates from 21 countries over a 20-year period identified the presence of a strong positive association between recorded mortality from stroke, hypertension and stomach cancer. However, the slopes of regression lines for secular trends analyses varied considerably from country to country, suggesting an inconsistency in the pattern of the relationship. 2. A death certificate study of diagnostic concordance correctly identified previously known disease associations but failed to recognise any special relationship between stroke and stomach cancer or hypertension and stomach cancer. 3. Our results fail to confirm the presence of a unique relationship between stroke and stomach cancer. On the basis of these observations, the hypothesis that exposure to salt increases an individual's risk of developing both stroke and stomach cancer seems unlikely.

Spatio-temporal constraints on upright children's coordination when hitting a moving target

2007 ◽  
Vol 30 (4) ◽  
pp. 666-678 ◽  
Author(s):  
Florence Rosey ◽  
Jean Keller ◽  
Eveline Golomer
Keyword(s):  
Moving Target ◽  
Temporal Constraints ◽  
Spatio Temporal

scholarly journals Explaining a Dark Side: Public Service Motivation, Presenteeism, and Absenteeism

2017 ◽  
Vol 39 (4) ◽  
pp. 487-510 ◽  
Author(s):  
Ulrich Thy Jensen ◽  
Lotte Bøgh Andersen ◽  
Ann-Louise Holten
Keyword(s):  
Public Service ◽  
High Performance ◽  
Panel Study ◽  
Positive Association ◽  
Public Service Motivation ◽  
Dark Side ◽  
Public And Private ◽  
Strong Positive Association ◽  
Public And Private Sector

Public service motivation (PSM) has many bright sides, but recent studies also find dark sides, connected to, for instance, higher stress and burnout. However, results on the PSM–absenteeism association are inconclusive. One reason could be that PSM increases presenteeism (going to work even when ill), which in turn increases absenteeism and counteracts—or even exceeds—PSM-based reductions of absenteeism. Based on a three-wave panel study of Danish public and private sector employees, we find a strong positive association between PSM and presenteeism and indications that the PSM–absenteeism link is mediated by presenteeism. The findings suggest that going to work even on days when employees feel ill is a potential dark side of PSM and that it may have long-term consequences for the extent to which employees are absent from their jobs due to sickness. This cautions managers not to expect that high PSM automatically guarantees high performance and low absence.

A Hierarchical Security Model for Multimedia Big Data

Big Data ◽  
2016 ◽  
pp. 441-453
Author(s):  
Min Chen
Keyword(s):  
Big Data ◽  
Access Control ◽  
Multimedia Data ◽  
Temporal Constraints ◽  
Security Model ◽  
Multimedia Big Data ◽  
Role Hierarchy ◽  
Data Volume ◽  
Spatio Temporal ◽  
Role Based

In this chapter, the author proposes a hierarchical security model (HSM) to enhance security assurance for multimedia big data. It provides role hierarchy management and security roles/rules administration by seamlessly integrating the role-based access control (RBAC) with the object-oriented concept, spatio-temporal constraints, and multimedia standard MPEG-7. As a result, it can deal with challenging and unique security requirements in the multimedia big data environment. First, it supports multilayer access control so different access permission can be conveniently set for various multimedia elements such as visual/audio objects or segments in a multimedia data stream when needed. Second, the spatio-temporal constraints are modeled for access control purpose. Finally, its security processing is efficient to handle high data volume and rapid data arrival rate.

Intergenerational transmission of ethnic identity in mixed native couples in Finland

2019 ◽  
Vol 63 (1) ◽  
pp. 103-123
Author(s):  
Ognjen Obućina ◽  
Jan Saarela
Keyword(s):  
Ethnic Identity ◽  
Parental Education ◽  
Positive Association ◽  
Individual Characteristics ◽  
Parental Education Level ◽  
Second Child ◽  
Ethnic Affiliation ◽  
First Child ◽  
Strong Positive Association ◽  
Using Data

The aim of this study is to analyse the factors determining the ethnic affiliation of children born to interethnic native couples in Finland, using data from couples with one Finnish-speaking and one Swedish-speaking partner, between 1988 and 2014. In addition to individual characteristics of each partner and contextual factors, we also consider the role of couple characteristics. We look at the affiliation of the first child, as well as the combined affiliation of the first two children, in order to analyse how often children from the same parents are affiliated to different ethnicities. Around 60% of first- and second-born children of interethnic couples born between 1988 and 2014 were affiliated to the Swedish-speaking minority. The affiliation of the second child seldom differs from that of the first. Children of mixed couples with a Swedish mother are more likely to be affiliated to the Swedish-speaking community. Boys are more likely than girls to be affiliated to the father’s community, and vice versa. In line with our expectations based on ethnic awareness, preference for cultural plurality and parental aspirations, the multivariate analysis shows a strong positive association between parental education level and the likelihood of the first child being Swedish speaking. The analysis also indicates that bargaining is not an important strategy when choosing a child’s ethnic identity.

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