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Despite the dramatic changes in land-use arising from expansion of the palm oil industry, soil biodiversity in oil palm plantations has been little investigated. The present study aims to assess the effect of organic waste recycling (empty fruit bunches, EFB) on soil biodiversity in a mature plantation in Sumatra, Indonesia. A chronosequence was delineated taking into account the time between the applications of EFB and soil sampling; intervals of 1, 3, 6, 12, 18 and 24 months were compared with control plots without EFB application. Soil physical and chemical characteristics and macrofauna and nematofauna populations were analysed. The findings highlighted three distinct periods: a first disturbance period (0-6 months) showing a marked increase in pH, potassium content, base saturation and macrofauna abundance, especially ants, whereas earthworm, millipede and nematode populations were substantially reduced; a resilience period (6-18 months); and a final period (18-24 months) showing an improvement in most soil fertility parameters and a high density of earthworms, millipedes and nematodes. The impact of EFB application on soil quality changed as a function of time, and the present results explain the apparent discrepancy of some previous published results. This research is the first stage towards developing new strategies for enhancing soil biodiversity and related services for sustainable oil palm cultivation. Additional keywords: Elaeis guineensis, empty fruit bunches, fertilisation practices, soil macrofauna, soil nematofauna., Introduction Oil palms have been planted on 16Mha globally, mostly in Indonesia and Malaysia, representing dramatic changes in land-use. Oil palm cultivation--given the combination of societal, agricultural and environmental issues [...]

A simple two-neuron model of a discrete Hopfield neural network is considered. The local stability is analyzed with the associated characteristic model. In order to study the dynamic behavior, the Fold bifurcation is examined. In the case of two neurons, one necessary condition for yielding the Fold bifurcation is found. In addition, the stability and direction of the fold bifurcation are determined by applying the normal form theory and the center manifold theorem. [ABSTRACT FROM AUTHOR]

Nowadays, microprocessors have become an essential tool in a widely set of industrial applications. Because of this, Engineering students, especially Industrial Engineering ones, should be properly taught in its use by implementing sufficiently interesting procedures. The authors consider that these procedures should allow students to manage most of the features that a standard microprocessor offers, such as I/O ports, timer counters, serial communication, or external interruptions. In this way, this article describes a wide and reasonable-priced set of microprocessor-based procedures that forces Industrial Engineering students to be familiarized with the described features. © 2004 Wiley Periodicals, Inc. Comput Appl Eng Educ 12: 145–151, 2004; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.20015 [ABSTRACT FROM AUTHOR]

In optimization problems, neural networks have been proved as an efficient method. Because of this, students of Engineering should learn this tool properly in subjects as “Optimal Control” or “Intelligent Control.” In this paper, a planning for neural networks teaching is proposed. As tool, Evenet-2000, a Java-based toolkit which allows to design and train neural networks with arbitrary architecture, is used. © 2003 Wiley Periodicals, Inc. Comput Appl Eng Educ 11: 1–5, 2003; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/cae.10033 [ABSTRACT FROM AUTHOR]

Earthworms are an important soil taxon as ecosystem engineers, providing a variety of crucial ecosystem functions and services. Little is known about their diversity and distribution at large spatial scales, despite the availability of considerable amounts of local-scale data. Earthworm diversity data, obtained from the primary literature or provided directly by authors, were collated with information on site locations, including coordinates, habitat cover, and soil properties. Datasets were required, at a minimum, to include abundance or biomass of earthworms at a site. Where possible, site-level species lists were included, as well as the abundance and biomass of individual species and ecological groups. This global dataset contains 10,840 sites, with 184 species, from 60 countries and all continents except Antarctica. The data were obtained from 182 published articles, published between 1973 and 2017, and 17 unpublished datasets. Amalgamating data into a single global database will assist researchers in investigating and answering a wide variety of pressing questions, for example, jointly assessing aboveground and belowground biodiversity distributions and drivers of biodiversity change.

Soil organisms, including earthworms, are a key component of terrestrial ecosystems. However, little is known about their diversity, their distribution, and the threats affecting them. We compiled a global dataset of sampled earthworm communities from 6928 sites in 57 countries as a basis for predicting patterns in earthworm diversity, abundance, and biomass. We found that local species richness and abundance typically peaked at higher latitudes, displaying patterns opposite to those observed in aboveground organisms. However, high species dissimilarity across tropical locations may cause diversity across the entirety of the tropics to be higher than elsewhere. Climate variables were found to be more important in shaping earthworm communities than soil properties or habitat cover. These findings suggest that climate change may have serious implications for earthworm communities and for the functions they provide., (Copyright © 2019 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)

Assessing how much management of agricultural landscapes, in addition to protected areas, can offset biodiversity erosion in the tropics is a central issue for conservation that still requires cross-taxonomic and landscape-scale studies. We measured the effects of Amazonia deforestation and subsequent land-use intensification in 6 agricultural areas (landscape scale), where we sampled plants and 4 animal groups (birds, earthworms, fruit flies, and moths). We assessed land-use intensification with a synthetic index based on landscape metrics (total area and relative percentages of land uses, edge density, mean patch density and diversity, and fractal structures at 5 dates from 1990 to 2007). Species richness decreased consistently as agricultural intensification increased despite slight differences in the responses of sampled groups. Globally, in moderately deforested landscapes species richness was relatively stable, and there was a clear threshold in biodiversity loss midway along the intensification gradient, mainly linked to a drop in forest cover and quality. Our results suggest anthropogenic landscapes with high-quality forest covering >40 % of the surface area may prevent biodiversity loss in Amazonia., (© 2018 Society for Conservation Biology.)

In this paper we consider a simple discrete Hopfield neural network model and analyze local stability using the associated characteristic model. In order to study the dynamic behavior of the quasi-periodic orbit, the Hopf bifurcation must be determined. For the case of two neurons, we find one necessary condition that yields the Hopf bifurcation. In addition, we determine the stability and direction of the Hopf bifurcation by applying normal form theory and the center manifold theorem. An example is given and a numerical simulation is performed to illustrate the results. We analyze the influence of bias weights on the stability of the quasi-periodic orbit and study the phase-locking phenomena for certain experimental results with Arnold Tongues in a particular weight configuration., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

We amplified the mRNA for cytokines in peripheral blood mononuclear cells (PBMC) and cerebrospinal fluid (CSF) cells from 18 multiple sclerosis (MS) patients and 21 other neurological patients, using reverse transcription polymerase chain reaction (RT-PCR). A radioactive hybridization of the amplified DNA allowed quantitation of mRNA levels. Expression of tumor necrosis factor (TNF)-alpha, interferon (IFN)-gamma and interleukin (IL)-10 mRNA was elevated in CSF cells of MS patients. IFN-gamma and IL-10 mRNA levels were higher in MS patients than in other inflammatory neurological diseases. In many MS patients, both proinflammatory and immunoregulatory cytokine messages were detected in the CSF compartment. Such immune reactivity in CSF, as opposed to the peripheral compartment, did not correlate with the clinical activity of the disease.