Slope aspect affects the seed mass spectrum of grassland vegetation

2004 ◽  
Vol 14 (4) ◽  
pp. 379-385 ◽  
Author(s):  
Péter Csontos ◽  
Júlia Tamás ◽  
János Podani
Keyword(s):  
Case Studies ◽  
Pannonian Basin ◽  
Seed Mass ◽  
Slope Aspect ◽  
Data Sets ◽  
Chi Square ◽  
New Findings ◽  
Positive Balance ◽  
Class 1 ◽  
Species Frequencies

Seed mass distribution in grassland communities of slopes of contrasting aspect was analysed in dolomite regions of the Pannonian Basin. Species frequencies were obtained for four pairs of data sets, which originated from corresponding south- and north-facing dolomite grasslands, thus forming four independent case studies. The data sets comprised 5–15 sample plots and 51–114 (average 85) species. The species were classified using an eight-class system reflecting their mean seed mass (MSM) records (class 1 being the lowest, MSM ≤ 0.2 mg; class 8 being the highest, MSM > 50 mg). Seed mass class distributions derived from slopes of contrasting aspect showed strong significant differences in chi-square tests for trend for all the four case studies. Small-seeded species (classes 1 and 2) showed a positive balance for the south-facing slopes, whereas large-seeded species (classes 5, 6, 7 and 8) were more frequent on north-facing slopes. Species with intermediate seed mass (classes 3 and 4) were not distinctive between the slopes. These results represent strong evidence of increased seed mass in the vegetation of north-facing grasslands, when compared to their south-facing counterparts. Among the phenomena potentially responsible for the new findings, we discuss the roles of microclimatic effects (especially drought stress and light regime), grass litter, interspecific competition and seed predation.

The Association Between Presenting Visual Impairment, Health, and Employment Status

2021 ◽  
Vol 115 (3) ◽  
pp. 204-214
Author(s):  
Michele C. McDonnall ◽  
Zhen S. McKnight
Keyword(s):  
Visual Impairment ◽  
Labor Force ◽  
Visual Impairments ◽  
Data Sets ◽  
Chi Square ◽  
Health And Nutrition ◽  
Labor Force Status ◽  
The People ◽  
Self Reports ◽  
Study Participants

Introduction: The purpose of this study was to investigate the effect of visual impairment and correctable visual impairment (i.e., uncorrected refractive errors) on being out of the labor force and on unemployment. The effect of health on labor force status was also investigated. Method: National Health and Nutrition Examination Survey (NHANES) data from 1999 to 2008 ( N = 15,650) was used for this study. Participants were classified into three vision status groups: normal, correctable visual impairment, and visual impairment. Statistical analyses utilized were chi-square and logistic regression. Results: Having a visual impairment was significantly associated with being out of the labor force, while having a correctable visual impairment was not. Conversely, having a correctable visual impairment was associated with unemployment, while having a visual impairment was not. Being out of the labor force was not significantly associated with health for those with a visual impairment, although it was for those with correctable visual impairments and normal vision. Discussion: Given previous research, it was surprising to find that health was not associated with being out of the labor force for those with visual impairments. Perhaps other disadvantages for the people with visual impairments identified in this study contributed to their higher out-of-the-labor-force rates regardless of health. Implications for practitioners: Researchers utilizing national data sets that rely on self-reports to identify visual impairments should realize that some of those who self-identify as being visually impaired may actually have correctable visual impairments. Current research is needed to understand why a majority of people with visual impairments are not seeking employment and have removed themselves from the labor force.

scholarly journals A Generalized Rayleigh Family of Distributions Based on the Modified Slash Model

Symmetry ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1226
Author(s):  
Inmaculada Barranco-Chamorro ◽  
Yuri A. Iriarte ◽  
Yolanda M. Gómez ◽  
Juan M. Astorga ◽  
Héctor W. Gómez
Keyword(s):  
Heavy Tails ◽  
Real Data ◽  
Rate Function ◽  
Data Sets ◽  
Estimation Of Parameters ◽  
Stochastic Representation ◽  
Likelihood Methods ◽  
Chi Square ◽  
Maximum Likelihood Methods ◽  
Family Of Distributions

Specifying a proper statistical model to represent asymmetric lifetime data with high kurtosis is an open problem. In this paper, the three-parameter, modified, slashed, generalized Rayleigh family of distributions is proposed. Its structural properties are studied: stochastic representation, probability density function, hazard rate function, moments and estimation of parameters via maximum likelihood methods. As merits of our proposal, we highlight as particular cases a plethora of lifetime models, such as Rayleigh, Maxwell, half-normal and chi-square, among others, which are able to accommodate heavy tails. A simulation study and applications to real data sets are included to illustrate the use of our results.

Managing Public Services Innovation

2001 ◽  
Author(s):  
Richard M. Walker ◽  
Emma L. Jeanes ◽  
Robert O. Rowlands
Keyword(s):  
Case Studies ◽  
Best Practice ◽  
Public Services ◽  
Housing Association ◽  
Evidence Based ◽  
Data Sets ◽  
Evidence Based Policy ◽  
Services Innovation ◽  
Longitudinal Case Studies

<i>Managing Public Services Innovation</i> provides an in-depth exploration of innovation and its management in the housing association sector. Drawing on longitudinal case studies and data sets, it explores techniques to develop evidence-based policy in the housing association sector, and makes recommendations for best practice.

scholarly journals Variety of Economic Share of Tourism on Tropical Islands

2010 ◽  
Vol 14 (1) ◽  
pp. 303-314
Author(s):  
Katarzyna Podhorodecka
Keyword(s):  
Case Studies ◽  
Correlation Coefficient ◽  
Spearman Correlation ◽  
Tropical Islands ◽  
Chi Square ◽  
Tropical Island ◽  
Positive Correlation ◽  
Detailed Case ◽  
Chi Square Test

Abstract The author seeks an answer to the question whether a higher intensity of tourism movement is connected with a higher share of tourism in the economy in selected tropical island territories. With the use of the Spearman correlation coefficient, the existence of the average positive correlation between the intensity of tourism movement and the share of tourism in the economy has been determined. In the second part of paper, the author looks at the conditions which affect the role of tourism in the economy in proportion to the intensity of tourism movement. For this purpose, the Chi-square test and detailed case studies of chosen tropical islands are discussed.

Informatics and Socio-Technical Challenges when Designing Solutions for Integrated eCare

2017 ◽  
pp. 261-289
Author(s):  
Sabine Koch ◽  
Maria Hägglund ◽  
Isabella Scandurra
Keyword(s):  
Integrated Care ◽  
Case Studies ◽  
Health Informatics ◽  
Information Needs ◽  
System Development ◽  
Collaborative Work ◽  
Successful Implementation ◽  
Data Sets ◽  
Technical Challenges ◽  
Definition Of

The central role of eHealth to enable the successful implementation of integrated care is commonly acknowledged today. This is easier said than done. To provide correct, understandable, and timely information at the point of need and to facilitate communication and decision support for a network of actors with different prerequisites and needs are some of the big challenges of integrated care. This book chapter focuses on the specific challenges related to informatics and socio-technical issues when designing solutions for integrated eCare. Methods for requirements elicitation, evaluation, and system development using user-centred design in collaborative environments involving a variety of stakeholders are presented. Case studies in homecare of older patients, in the care of stroke patients, and regarding citizen eHealth services in general illustrate the application of these methods. Possible solutions and pitfalls are discussed based on the experiences drawn from the case studies. To address the main informatics and socio-technical challenges in integrated eCare, namely informatics-supported collaborative work and to provide coordinated continuity for the patient, top-down activities such as health informatics standardisation, and bottom-up activities resulting in the definition of concrete patient journey descriptions, interaction points, information needs (that can be transformed into standardised data sets), as well as visualisation and interaction patterns need to go hand in hand.

Statistical Tests of Type I Error

2021 ◽  
pp. 90-120
Author(s):  
Charles Auerbach
Keyword(s):  
Control Charts ◽  
Sampling Error ◽  
Statistical Tests ◽  
Statistical Significance ◽  
Data Sets ◽  
Chi Square ◽  
Statistical Process ◽  
Incorrect Decision ◽  
Type 1 Error ◽  
Statistical Process Control Charts

This chapter covers tests of statistical significance that can be used to compare data across phases. These are used to determine whether observed outcomes are likely the result of an intervention or, more likely, the result of sampling error or chance. The purpose of a statistical test is to determine how likely it is that the analyst is making an incorrect decision by rejecting the null hypothesis, that there is no difference between compared phases, and accepting the alternative one, that true differences exist. A number of tests of significance are presented in this chapter: statistical process control charts (SPCs), proportion/frequency, chi-square, the conservative dual criteria (CDC), robust conservative dual criteria (RCDC), the t test, and analysis of variance (ANOVA). How and when to use each of these are also discussed, and examples are provided to illustrate each. The method for transforming autocorrelated data and merging data sets is discussed further in the context of utilizing transformed data sets to test of Type 1 error.

Analyzing Group Data

2021 ◽  
pp. 121-142
Author(s):  
Charles Auerbach
Keyword(s):  
Control Charts ◽  
Type I Error ◽  
Statistical Significance ◽  
Data Sets ◽  
Type I ◽  
Chi Square ◽  
Statistical Process ◽  
Incorrect Decision ◽  
Group Data ◽  
Statistical Process Control Charts

This chapter covers tests of statistical significance that can be used to compare data across phases. These are used to determine whether observed outcomes are likely the result of an intervention or, more likely, the result of chance. The purpose of a statistical test is to determine how likely it is that the analyst is making an incorrect decision by rejecting the null hypothesis and accepting the alternative one. A number of tests of significance are presented in this chapter: statistical process control charts (SPCs), proportion/frequency, chi-square, the conservative dual criteria (CDC), robust conservative dual criteria (RCDC), the t test, and analysis of variance (ANOVA). How and when to use each of these are also discussed. The method for transforming autocorrelated data and merging data sets is discussed. Once new data sets are created using the Append() function, they can be tested for Type I error using the techniques discussed in the chapter.

scholarly journals Phylogenetic position and taxonomy of Cycloseris explanulata and C. wellsi (Scleractinia: Fungiidae): lost mushroom corals find their way home

2012 ◽  
Vol 81 (3) ◽  
pp. 125-146 ◽  
Author(s):  
Francesca Benzoni ◽  
Roberto Arrigoni ◽  
Fabrizio Stefani ◽  
Bastian T. Reijnen ◽  
Simone Montano ◽  
...  
Keyword(s):  
Molecular Study ◽  
Molecular Data ◽  
Phylogenetic Position ◽  
Distribution Data ◽  
Data Sets ◽  
Free Living ◽  
New Findings ◽  
The Family ◽  
Ecological Implications ◽  
History Of

The scleractinian species Psammocora explanulata and Coscinaraea wellsi were originally classified in the family Siderastreidae, but in a recent morpho-molecular study it appeared that they are more closely related to each other and to the Fungiidae than to any siderastreid taxon. A subsequent morpho-molecular study of the Fungiidae provided new insights regarding the phylogenetic relationships within that family. In the present study existing molecular data sets of both families were analyzed jointly with those of new specimens and sequences of P. explanulata and C. wellsi. The results indicate that both species actually belong to the Cycloseris clade within the family Fungiidae. A reappraisal of their morphologic characters based on museum specimens and recently collected material substantiate the molecular results. Consequently, they are renamed Cycloseris explanulata and C. wellsi. They are polystomatous and encrusting like C. mokai, another species recently added to the genus, whereas all Cycloseris species were initially thought to be monostomatous and free-living. In the light of the new findings, the taxonomy and distribution data of C. explanulata and C. wellsi have been updated and revised. Finally, the ecological implications of the evolutionary history of the three encrusting polystomatous Cycloseris species and their free-living monostomatous congeners are discussed.

scholarly journals The Developmental Phases of Zebrafish Myogenesis

2019 ◽  
Vol 7 (2) ◽  
pp. 12 ◽  
Author(s):  
Samuel R. Keenan ◽  
Peter D. Currie
Keyword(s):  
Molecular Mechanisms ◽  
Muscle Growth ◽  
Data Sets ◽  
Vertebrate Lineage ◽  
New Findings ◽  
Muscle Groups ◽  
Teleost Muscle ◽  
Axial Musculature ◽  
Developmental Phases ◽  
Type Specification

The development and growth of vertebrate axial muscle have been studied for decades at both the descriptive and molecular level. The zebrafish has provided an attractive model system for investigating both muscle patterning and growth due to its simple axial musculature with spatially separated fibre types, which contrasts to complex muscle groups often deployed in amniotes. In recent years, new findings have reshaped previous concepts that define how final teleost muscle form is established and maintained. Here, we summarise recent findings in zebrafish embryonic myogenesis with a focus on fibre type specification, followed by an examination of the molecular mechanisms that control muscle growth with emphasis on the role of the dermomyotome-like external cell layer. We also consider these data sets in a comparative context to gain insight into the evolution of axial myogenic patterning systems within the vertebrate lineage.

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