26 research outputs found
Frequentist and Bayesian measures of confidence via multiscale bootstrap for testing three regions
A new computation method of frequentist -values and Bayesian posterior
probabilities based on the bootstrap probability is discussed for the
multivariate normal model with unknown expectation parameter vector. The null
hypothesis is represented as an arbitrary-shaped region. We introduce new
parametric models for the scaling-law of bootstrap probability so that the
multiscale bootstrap method, which was designed for one-sided test, can also
computes confidence measures of two-sided test, extending applicability to a
wider class of hypotheses. Parameter estimation is improved by the two-step
multiscale bootstrap and also by including higher-order terms. Model selection
is important not only as a motivating application of our method, but also as an
essential ingredient in the method. A compromise between frequentist and
Bayesian is attempted by showing that the Bayesian posterior probability with
an noninformative prior is interpreted as a frequentist -value of
``zero-sided'' test
Spatial patterns of large African cats : a large-scale study on density, home range size, and home range overlap of lions Panthera leo and leopards Panthera pardus
SUPPORTING INFORMATION : APPENDIX S1. Site information. APPENDIX S2. Intuitive explanation of the autocorrelated kernel density estimator. APPENDIX S3. Sources of density data. APPENDIX S4. Mathematical modifications of Jetz et al.âs (2014) overlap equation. APPENDIX S5. Lion pride size data.1. Spatial patterns of and competition for resources by territorial carnivores are
typically explained by two hypotheses: 1) the territorial defence hypothesis
and 2) the searching efficiency hypothesis.
2. According to the territorial defence hypothesis, when food resources are abundant,
carnivore densities will be high and home ranges small. In addition,
carnivores can maximise their necessary energy intake with minimal territorial
defence. At medium resource levels, larger ranges will be needed, and it will
become more economically beneficial to defend resources against a lower
density of competitors. At low resource levels, carnivore densities will be low
and home ranges large, but resources will be too scarce to make it beneficial
to defend such large territories. Thus, home range overlap will be minimal
at intermediate carnivore densities.
3. According to the searching efficiency hypothesis, there is a cost to knowing
a home range. Larger areas are harder to learn and easier to forget, so carnivores
constantly need to keep their cognitive map updated by regularly
revisiting parts of their home ranges. Consequently, when resources are scarce,
carnivores require larger home ranges to acquire sufficient food. These larger
home ranges lead to more overlap among individualsâ ranges, so that overlap in home ranges is largest when food availability is the lowest. Since conspecific
density is low when food availability is low, this hypothesis predicts that
overlap is largest when densities are the lowest.
4. We measured home range overlap and used a novel method to compare
intraspecific home range overlaps for lions Panthera leo (n = 149) and leopards
Panthera pardus (n = 111) in Africa. We estimated home range sizes
from telemetry location data and gathered carnivore density data from the
literature.
5. Our results did not support the territorial defence hypothesis for either species.
Lion prides increased their home range overlap at conspecific lower
densities whereas leopards did not. Lion pride changes in overlap were primarily
due to increases in group size at lower densities. By contrast, the
unique dispersal strategies of leopards led to reduced overlap at lower densities.
However, when human-caused
mortality was higher, leopards increased
their home range overlap. Although lions and leopards are territorial, their
territorial behaviour was less important than the acquisition of food in determining
their space use. Such information is crucial for the future conservation
of these two iconic African carnivores.The Natural Sciences and Engineering Research Council of Canada and a Hugh Kelly Fellowship from Rhodes University, Grahamstown, SA.https://onlinelibrary.wiley.com/journal/13652907am2024Centre for Wildlife ManagementMammal Research InstituteZoology and EntomologySDG-15:Life on lan
Some Properties Of Somerville Multiple Range Subset-Selection Procedure For three Populations
Somerville (1984) has recently proposed a multiple range subset selection procedure for the case when sample means of size n are obtained from k normal populations with common known variance. It is shown here that when k=3 the probability of correct selection 6f this procedure is between that of Gupta\u27s procedure and p* and strong evidence is presented that the expected subset size of the procedure is lower than that of Gupta\u27s procedure uniformly in parameter values for all p* 0,98
Taxonomy for complexity theory in the context of maternity care
Background
The linear focus of ânormal scienceâ is unable toadequately take account of the complex interactions that direct health care systems. There is a turn towards complexity theory as a more appropriate framework for understanding system behaviour. However, a comprehensive taxonomy for complexity theory in the context of health care is lacking.
Objective
This paper aims to build a taxonomy based on the key complexity theory components that have been used in publications on complexity theory and health care, and to explore their explanatory power for health care system behaviour, specifically for maternity care.
Method
A search strategy was devised in PubMed and 31 papers were identified as relevant for the taxonomy.
Findings
The final taxonomy for complexity theory included and defined 11components. The use of waterbirth and the impact of the Term Breech trial showed that each of the components of our taxonomy has utility in helping to understand how these techniques became widely adopted. It is not just the components themselves that characterise a complex system but also the dynamics between them
Oxygen consumption and ammonia excretion of the searobin Prionotus punctatus (Scorpaeniformes, Triglidae) at two different temperatures
Routine oxygen consumption and ammonia excretion were measured at 20ÂșC and 25ÂșC in the searobin Prionotus punctatus collected in Ubatuba region (22Âș30'S), SP, Brazil, in western South Atlantic, to investigate energy expenditure and losses through metabolic processes. IndividuaIs ranging from 1.00g to 88.47g and from 1.79g to 56.50g were used in experiments at 20ÂșC and 25ÂșC, respectively. At 20ÂșC and 25ÂșC, the averages of weight-specific oxygen consumption for the weight class of 1.00 - 10.00g, common to both temperatures, were 162.46” 39.51 ”.10z/g/h and 200.47” 92.46 ”.10z/g/h, respectively; for the weight class of 50.01 - 60.00g these values were 112.30 ” 22.84 ”.10z/g/h and 114.60 ” 20.36 ”.10zlg/h. At 20ÂșC and 25ÂșC, the averages of weight-specific ammonia excretion for the weight class of 1.00 to 1O.00g were 1.03 ” 0.37 fJ.M/g/h and 1.21 ” 0.65 ”.M/g/h, respectively; for the weight class of 50.01 -60.00g these values were 0.68 ” 0.13 fJ.M/g/h and 0.60 ” 0.22 ”.M/g/h. The energy budget for the species was calculated at both temperatures using the experimental data and a model for marine teleosts proposed in the literature.<br>O consumo de oxigĂȘnio de rotina e a excreção de amĂŽnia de Prionotus punctatus coletados na regiĂŁo de Ubatuba (22Âș30'S), SP, Brasil, foram medidos a 20ÂșC e 25ÂșC, para avaliar os gastos e perdas de energia com os processos metabĂłlicos. Foram utilizados indivĂduos variando de 1,00g a 88,47g e de 1,79g a 56,50g, em experimentos a 20ÂșC e 25ÂșC, respectivamente. As mĂ©dias de consumo especĂfico de oxigĂȘnio a 20ÂșC e 25ÂșC para a classe de peso de 1,00 - 10,00g, comum a ambas as temperaturas, foram 162,46” 39,51 ”.10z/g/h e 200,47 ” 92,46 ”.10z/g/h, respectivamente; para a classe de peso de 50,01 - 60,00g esses valores foram 112,30 ” 22,84 ”.10z/g/h e 114,60 ” 20,36 ”.10z/g/h. A 20ÂșC e 25ÂșC, as mĂ©dias de excreção especĂfica de amĂŽnia para a classe de peso de 1,00 a 10,00g foram 1,03 ” 0,37 e 1,21 ” 0,65 ”.M/g/h, respectivamente; para a classe de peso de 50,01 - 60,00g esses valores foram 0,68 ” 0,13 ”.M/g/h e 0,60 ” 0,22 ”.M/g/h. O orçamento energĂ©tico para a espĂ©cie foi calculado para cada temperatura utilizando-se os da.dos experimentais e modelo proposto na literatura
The Fungal Sexual Pheromone Sirenin Activates the Human CatSper Channel Complex
The basal fungus <i>Allomyces
macrogynus</i> (<i>A. macrogynus</i>) produces motile
male gametes displaying well-studied
chemotaxis toward their female counterparts. This chemotaxis is driven
by sirenin, a sexual pheromone released by the female gametes. The
pheromone evokes a large calcium influx in the motile gametes, which
could proceed through the cation channel of sperm (CatSper) complex.
Herein, we report the total synthesis of sirenin in 10 steps and 8%
overall yield and show that the synthetic pheromone activates the
CatSper channel complex, indicated by a concentration-dependent increase
in intracellular calcium in human sperm. Sirenin activation of the
CatSper channel was confirmed using whole-cell patch clamp electrophysiology
with human sperm. Based on this proficient synthetic route and confirmed
activation of CatSper, analogues of sirenin can be designed as blockers
of the CatSper channel that could provide male contraceptive agents