Predicting coexistence of plants subject to a tolerance-competition trade-off

Ecological trade-offs between species are often invoked to explain species coexistence in ecological communities. However, few mathematical models have been proposed for which coexistence conditions can be characterized explicitly in terms of a trade-off. Here we present a model of a plant community which allows such a characterization. In the model plant species compete for sites where each site has a fixed stress condition. Species differ both in stress tolerance and competitive ability. Stress tolerance is quantified as the fraction of sites with stress conditions low enough to allow establishment. Competitive ability is quantified as the propensity to win the competition for empty sites. We derive the deterministic, discrete-time dynamical system for the species abundances. We prove the conditions under which plant species can coexist in a stable equilibrium. We show that the coexistence conditions can be characterized graphically, clearly illustrating the trade-off between stress tolerance and competitive ability. We compare our model with a recently proposed, continuous-time dynamical system for a tolerance-fecundity trade-off in plant communities, and we show that this model is a special case of the continuous-time version of our model.Comment: To be published in Journal of Mathematical Biology. 30 pages, 5 figures, 5 appendice

Illocutionary Force in the Novel Darkest Hour by Cleo Virginia Andrews

One aim of this article is to show through concrete examples about how Illocutionary Force used in Novel Darkest Hour By Cleo Virginia Andrews. The research are to describe the six types of illocutionary force in Cleo Virginia Andrews\u27s Darkest Hour to derive the most dominant type of illocutionary force, to explain the meaning of illocutionary force and to analyze the implication of that dominant the six types of illocutionary force to the novel itself. This study applied descriptive qualitative method. They were taken randomly and found 108 the types of illocutionary force; Asserting (21,29 %), Promising (13,89 %), Excomunicating ( 12,04%), Exclaiming in pain (15,74 %), Inquiring (11,11 %), and Ordering (25,92%) occurs in the novel. It was found that the most dominant type of illocutionary force that is used in Cleo Virginia Andrews\u27s Darkest Hour is Ordering for expressing what the speaker wants (25,92%). This implies that the Ordering for expressing what the speaker wants play a great role in the novel. It means that wishes as expression of speaker\u27s desire or wants in order to expect it becomes a reality can be characteristic of the novel in case of applying order to express of Illocutionary Force within utterances

Development of Pratylenchus Coffeae in Biochar Applied Soil, Coffee Roots and Its Effect on Plant Growth

Biochar improve physical, chemical and biological properties of soil. It may also be used as botanical pesticides. The experiment was aimed to determine the effect of biochar on population development of parasitic nematode Pratylenchus coffeae. The experiment was carried out in Nematology Laboratory and in a greenhouse of Indonesian Coffee and Cocoa Research Institute (ICCRI), Jember, Indonesia. The experiment was arranged according to completely randomized design with six treatments of biochar concentrations, i.e. 4%; 3%; 2%; 1%; 0.5% and 0% dry weight of soil. Research results revealed that biochar application of 4.0% was effectively killed 74.5% of P. coffeae, while the lowest mortality level of 37.5% at biochar 0.5% treatment. In the greenhouse trial, application of biochar 4.0% was the most effective in suppressing the population of parasitic nematode in coffee seedlings. Application of biochar was also able to increase the growth and biomass of coffee seedlings

The Hypermasculine and Ubersexual Men in the Harlequin Novels of the 1980s and 2000s

Harlequin novels are so popular that Harlequin romance emerges as a genre. Unlike on the heroines, there are scarcely any studies or works on the heroes, thus, I want to focus my study on the heroes of Harlequin Romance. By analyzing using the Male Sex Role in the 1980s and themes of masculinity in the 2000s, I will prove that there are four types of ideal men in the 1980s Harlequin novels whose characteristics originated from the ideal men in the society at that time, the Hypermasculine men with extreme masculinity and avoidance of any feminine sides. I will also prove that there are three types of ideal men in the 2000s Harlequin novels whose characteristics are in accordance with the Ubersexual men\u27s, the ideal men in the society in 2000s having positive characteristics of traditional manliness with some “feminine“ characteristics. The reason behind these changes is because of the changes in the heroines and the characteristics of men in the society in time and these push for the changes in the heroes. As a publisher, Harlequin\u27s goal is the highest selling rate, thus, they adjust to the market\u27s demand

Implementasi Teknologi Global Position System Dalam Deteksi Posisi Mobil Berbasis Short Message Service

Pada zaman sekarang ini teknologi berkembang secara cepat dan pesat.Diantaranya dapat di temukan pada sistem pengaman kendaraan khususnya pada mobil. Terkadang manusia harus meninggalkan mobil untuk menyelesaikan beberapa hal dalam waktu yang lama. Kondisi seperti itu dapat menimbulkan adanya tindak pencurian yang merupakan tindakan kejahatan yang tak terduga. Untuk mengatasi masalah di atas adalah membuat alat keamanan dengan memanfaatkan teknologi GPS dan ponsel untuk mengetahui posisi benda bergerak berbasis mikrokontroler AT89S51 yang bekerja secara otomatis akan mengirimkan posisi benda yang berupa titik kordinat dengan cara mengirimkan SMS ke ponsel pada alat dengan format sesuai dengan yang telah ditentukan. Dengan demikian pemilik mobil dapat mengetahui posisi mobil bila telah terjadi pencurian dan dapat segera melapor ke pihak berwajib. Sehingga dapat memudahkan aparat dalam mengungkap kasus pencurian

Eccentricity Evolution for Planets in Gaseous Disks

We investigate the hypothesis that interactions between a giant planet and the disk from which it forms promote eccentricity growth. These interactions are concentrated at discrete Lindblad and corotation resonances. Interactions at principal Lindblad resonances cause the planet's orbit to migrate and open a gap in the disk if the planet is sufficiently massive. Those at first order Lindblad and corotation resonances change the planet's orbital eccentricity. Eccentricity is excited by interactions at external Lindblad resonances which are located on the opposite side of corotation from the planet, and damped by co-orbital Lindblad resonances which overlap the planet's orbit. If the planet clears a gap in the disk, the rate of eccentricity damping by co-orbital Lindblad resonances is reduced. Density gradients associated with the gap activate eccentricity damping by corotation resonances at a rate which initially marginally exceeds that of eccentricity excitation by external Lindblad resonances. But the corotation torque drives a mass flux which reduces the density gradient near the resonance. Sufficient partial saturation of corotation resonances can tip the balance in favor of eccentricity excitation. A minimal initial eccentricity of a few percent is required to overcome viscous diffusion which acts to unsaturate corotation resonances by reestablishing the large scale density gradient. Thus eccentricity growth is a finite amplitude instability. Formally, interactions at the apsidal resonance, which is a special kind of co-orbital Lindblad resonance, appears to damp eccentricity faster than external Lindblad resonances can excite it. However, apsidal waves have such long wavelengths that they do not propagate in protoplanetary disks. This reduces eccentricity damping by the apsidal resonance to a modest level.Comment: Submitted to Ap

Jets in GRBs: Tests and Predictions for the Structured Jet Model

The two leading interpretations of achromatic breaks that are observed in the light curves of GRBs afterglow are (i) the manifestation of the edge of a jet, which has a roughly uniform energy profile and a sharp edge and (ii) a line of sight effect in jets with a variable energy profile. The first scenario requires the inner engine to produce a jet with a different opening angle each explosion, while the latter requires a standard engine. The physical structure of the jet is a crucial factor in understanding GRB progenitors, and therefore discriminating the two jet scenarios is particularly relevant. In the structured jet case, specific predictions can be made for the distribution of observed break angles $\theta_{\rm break}$, while that distribution is arbitrary in the first scenario. We derive the theoretical distribution for the structured jet model. Specifically, we predict the most common angle to be about 0.12 rad, in rough agreement with the sample. If this agreement would hold as the sample size increases, it would strengthen the case for the standard jet hypothesis. We show that a prediction of this model is that the average viewing angle is an increasing function of the survey sensitivity, and in particular that a mission like {\em Swift} will find the typical viewing angle to be about 0.3 rad. The local event rate predicted by this model is $R_{\rm GRB}(z=0)\sim 0.5$ Gpc$^{-3}$ yr$^{-1}$.Comment: 14 pages, 3 figures; accepted to Ap

Broad-band Modeling of GRB Afterglows

Observations of GRB afterglows ranging from radio to X-ray frequencies generate large data sets. Careful analysis of these broad-band data can give us insight into the nature of the GRB progenitor population by yielding such information like the total energy of the burst, the geometry of the fireball and the type of environment into which the GRB explodes. We illustrate, by example, how global, self-consistent fits are a robust approach for characterizing the afterglow emission. This approach allows a relatively simple comparison of different models and a way to determine the strengths and weaknesses of these models, since all are treated self-consistently. Here we quantify the main differences between the broad-band, self-consistent approach and the traditional approach, using GRB000301C and GRB970508 as test cases.Comment: Appears in "Gamma-Ray Bursts in the Afterglow Era" proceedings of the Roma 2000 GRB Workshop; 3 pages; 2 figure

Recovery Among People with Mental Illness (PMI) as Perceived by the Caregivers in Islamic Boarding School (IBS) in Indonesia

Background: Mental hospitals as places to rehabilitation people with mental illness(PMI) in Indonesia are limited in numbers and do not meet with the number of PMI.The society may contribute in facilitating recovery and rehabilitation place for PMI including Islamic boarding school. Some Islamic boarding schools provide rehabilitation for PMI to help with recovery process. Recovery is an important aspect to assess the success of PMI rehabilitation. Nevertheless, there has been no study on Islamic boarding school\u27s caregivers\u27 perception on PMI recovery.Purpose: This study aims to explore recovery perception of caregivers treating PMI in Islamic boarding school and factors affecting recovery.Methods: Data are acquired from 19 caregivers from three Islamic boarding schools providing rehabilitation for PMI with Focus Group Discussion (FGD). The data analyzed using descriptive analysis.Result: Having a good communication is a recovery criterion that is mentioned themost by caregivers. There are three biggest factors affecting recovery based on the caregivers such as prayers or religion followed by social support from family and environment and also doing activities.Conclusion: The results may depict the PMI recovery so that the health care providers can provide interventions that can support the recovery process in PMI