3,202 research outputs found
Evaluating indices of traditional ecological knowledge: a methodological contribution
BACKGROUND: New quantitative methods to collect and analyze data have produced novel findings in ethnobiology. A common application of quantitative methods in ethnobiology is to assess the traditional ecological knowledge of individuals. Few studies have addressed reliability of indices of traditional ecological knowledge constructed with different quantitative methods. METHODS: We assessed the associations among eight indices of traditional ecological knowledge from data collected from 650 native Amazonians. We computed Spearman correlations, Chronbach's alpha, and principal components factor analysis for the eight indices. RESULTS: We found that indices derived from different raw data were weakly correlated (rho<0.5), whereas indices derived from the same raw data were highly correlated (rho>0.5; p < 0.001). We also found a relatively high internal consistency across data from the eight indices (Chronbach's alpha = 0.78). Last, results from a principal components factor analysis of the eight indices suggest that the eight indices were positively related, although the association was low when considering only the first factor. CONCLUSION: A possible explanation for the relatively low correlation between indices derived from different raw data, but relatively high internal consistency of the eight indices is that the methods capture different aspects of an individual's traditional ecological knowledge. To develop a reliable measure of traditional ecological knowledge, researchers should collect raw data using a variety of methods and then generate an aggregated measure that contains data from the various components of traditional ecological knowledge. Failure to do this will hinder cross-cultural comparisons
The role of ambiguous expectancy in differential inhibition: A different role for context from direct US association.
High overlap between traditional ecological knowledge and forest conservation found in the Bolivian Amazon
Unidad de excelencia María de Maeztu MdM-2015-0552Altres ajuts: FBBVA research grant (BIOCON_06_106-07)It has been suggested that traditional ecological knowledge (TEK) may play a key role in forest conservation. However, empirical studies assessing to what extent TEK is associated with forest conservation compared with other variables are rare. Furthermore, to our knowledge, the spatial overlap of TEK and forest conservation has not been evaluated at fine scales. In this paper, we address both issues through a case study with Tsimane' Amerindians in the Bolivian Amazon. We sampled 624 households across 59 villages to estimate TEK and used remote sensing data to assess forest conservation. We ran statistical and spatial analyses to evaluate whether TEK was associated and spatially overlapped with forest conservation at the village level. We find that Tsimane' TEK is significantly and positively associated with forest conservation although acculturation variables bear stronger and negative associations with forest conservation. We also find a very significant spatial overlap between levels of Tsimane' TEK and forest conservation. We discuss the potential reasons underpinning our results, which provide insights that may be useful for informing policies in the realms of development, conservation, and climate. We posit that the protection of indigenous cultural systems is vital and urgent to create more effective policies in such realms
In-flame soot quantification of diesel sprays under sooting/non-sooting critical conditions in an optical engine
[EN] Because of the challenge of meeting stringent emissions regulations for internal combustion engines, some advanced
low temperature combustion modes have been raised in recent decades to improve combustion efficiency.
Therefore, detailed understanding and capability for accurate prediction of in-flame soot processes under
such low sooting conditions are becoming necessary. Nowadays, a lot of investigations have been carried out to
quantify in-flame soot in Diesel sprays under high sooting conditions by means of different optical techniques.
However, no information of soot quantification can be found for sooting/non-sooting critical conditions. In
current study, the instantaneous soot production in a two-stroke optical engine under low sooting conditions has
been measured by means of a Diffused back-illumination extinction technique (DBI) and two-color method (2C)
simultaneously. The fuels used were n-dodecane and n-heptane, which have been injected separately though two
different injectors equipped with single-hole nozzles. A large cycle-to-cycle variation on soot production can be
observed under such operating conditions, however the in-cylinder heat release traces were quite repeatable. It is
the same with the well-known trends of soot amount to operating conditions that the probability of sooting
cycles increases with higher ambient temperature, higher ambient density and lower injection pressure. Both
techniques present a pretty good agreement on soot amount when the peak of KL value is close to 1. However,
the KL value of two-color method becomes bigger than that of DBI and the difference increases with lower
sooting conditions.This study was partially funded by the Natural Science Foundation of China (No. 51876083), China Postdoctoral Science Foundation (2018M642176) and High-tech Research Key laboratory of Zhenjiang (SS2018002)Xuan, T.; Pastor, JV.; García-Oliver, JM.; García Martínez, A.; He, Z.; Wang, Q.; Reyes, M. (2019). In-flame soot quantification of diesel sprays under sooting/non-sooting critical conditions in an optical engine. Applied Thermal Engineering. 149:1-10. https://doi.org/10.1016/j.applthermaleng.2018.11.112S11014
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Morphological estimation of Cellularity on Neo-adjuvant treated breast cancer histological images
This paper describes a methodology that extracts morphological features from histological breast cancer images stained for Hematoxilyn and Eosin (H&E). Cellularity was estimated and the correlation between features and the residual tumour size cellularity after a Neo-Adjuvant treatment (NAT) was examined. Images from whole slide imaging (WSI) were processed automatically with traditional computer vision methods to extract twenty two morphological parameters from the nuclei, epithelial region and the global image. The methodology was applied to a set of images from breast cancer under NAT. The data came from the BreastPathQ Cancer Cellularity Challenge 2019, and consisted of 2579 patches of 255×255 pixels of H&E histopatological samples from NAT treatment patients. The methodology automatically implements colour separation, segmentation and morphological analysis using traditional algorithms (K-means grouping, watershed segmentation, Otsu’s binarisation). Linear regression methods were applied to determine strongest correlation between the parameters and the cancer cellularity. The morphological parameters showed correlation with the residual tumour cancer cellularity. The strongest correlations corresponded to the stroma concentration value (r = −0.9786) and value from HSV image colour space (r = −0.9728), both from a global image parameters
Cash Cropping, Farm Technologies, and Deforestation: What are the Connections? A Model with Empirical Data from the Bolivian Amazon
Research suggests that cash cropping is positively associated with deforestation. We use three-year data (2000-2002, inclusive) from 493 households to estimate the association between cash cropping rice and deforestation. Doubling the area sown with rice is associated with a 26-30 percent increase in the area of forest cleared during the next cropping season. We simulate the changes in rice cultivation to reach a daily income level of $1/person from cash cropping rice. We find that within 10 years: (1) the amount of deforestation would triple, (2) work requirements would exceed household's labor availability, and (3) fallows duration would decrease two-fold. To avoid the increase of deforestation from cash cropping requires increasing productivity, diversification of income sources, or both
Reliability of P mode event classification using contemporaneous BiSON and GOLF observations
We carried out a comparison of the signals seen in contemporaneous BiSON and
GOLF data sets. Both instruments perform Doppler shift velocity measurements in
integrated sunlight, although BiSON perform measurements from the two wings of
potassium absorption line and GOLF from one wing of the NaD1 line.
Discrepancies between the two datasets have been observed. We show,in fact,
that the relative power depends on the wing in which GOLF data observes. During
the blue wing period, the relative power is much higher than in BiSON datasets,
while a good agreement has been observed during the red period.Comment: 7 pages, HELAS II: Helioseismology, Asteroseismology, and MHD
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Nou mètode per avaluar la importància social de les plantes
El valor econòmic d'una planta no té perquè ser el mateix que el seu valor cultural. Es més, poden ser força diferents. Un grup d'investigadors ha establert un nou mètode que permet mesurar aquesta rellevància des de tres vessants: cultural, pràctica i econòmica i l'ha aplicat en un estudi realitzat a un grup indígena de l'Amazònia boliviana.El valor económico de una planta no tiene porqué ser el mismo que suvalor cultural. De hecho, pueden ser bastante diferentes. Un grupo deinvestigadores ha establecido un nuevo método que permite medir estarelevancia desde tres vertientes: cultural, práctica y económica y lo haaplicado en un estudio realizado entre un grupo indígena de laAmazonia boliviana
An infinite family of magnetized Morgan-Morgan relativistic thin disks
Applying the Horsk\'y-Mitskievitch conjecture to the empty space solutions of
Morgan and Morgan due to the gravitational field of a finite disk, we have
obtained the corresponding solutions of the Einstein-Maxwell equations. The
resulting expressions are simply written in terms of oblate spheroidal
coordinates and the solutions represent fields due to magnetized static thin
disk of finite extension. Now, although the solutions are not asymptotically
flat, the masses of the disks are finite and the energy-momentum tensor agrees
with the energy conditions. Furthermore, the magnetic field and the circular
velocity show an acceptable physical behavior.Comment: Submitted to IJTP. This paper is a revised and extended version of a
paper that was presented at arXiv:1006.203
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An empirical comparison of knowledge and skill in the context of traditional ecological knowledge
Background: We test whether traditional ecological knowledge (TEK) about how to make an item predicts a person's skill at making it among the Tsimane' (Bolivia). The rationale for this research is that the failure to distinguish between knowledge and skill might account for some of the conflicting results about the relationships between TEK, human health, and economic development. Methods: We test the association between a commonly-used measure of individual knowledge (cultural consensus analysis) about how to make an arrow or a bag and a measure of individual skill at making these items, using ordinary least-squares regression. The study consists of 43 participants from 3 villages. Results: We find no association between our measures of knowledge and skill (core model, p > 0.5, R2 = .132). Conclusions: While we cannot rule out the possibility of a real association between these phenomena, we interpret our findings as support for the claim that researchers should distinguish between methods to measure knowledge and skill when studying trends in TEK
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