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Animal abundance estimation is increasingly based on drone or aerial survey photography. Manual postprocessing has been used extensively; however, volumes of such data are increasing, necessitating some level of automation, either for complete counting, or as a labour‐saving tool. Any automated processing can be challenging when using such tools on species that nest in close formation such as Pygoscelis penguins. We present here a customized CNN‐based density map estimation method for counting of penguins from low‐resolution aerial photography. Our model, an indirect regression algorithm, performed significantly better in terms of counting accuracy than standard detection algorithm (Faster‐RCNN) when counting small objects from low‐resolution images and gave an error rate of only 0.8 percent. Density map estimation methods as demonstrated here can vastly improve our ability to count animals in tight aggregations and demonstrably improve monitoring efforts from aerial imagery. [ABSTRACT FROM AUTHOR]

Calculating the height at which birds fly over the sea is a challenging task, but remains important to assessing collision risk in proposed offshore wind farm areas for consenting purposes. This could be done by several methods (e.g. GPS or laser rangefinders), but each have biases that make it difficult to generate site-wide assessments. Digital video aerial surveys, which quickly cover large areas, were used to assess flight heights of northern gannets and black-legged kittiwakes using a photogrammetric technique combined with a semi-automated measurement tool. The lengths of birds known to be at sea surface, as identified by reflection on the water, were compared to lengths of birds at unknown height to generate individual flight height profiles. Validation of the method on kittiwake found that LiDAR produced mean flights that were not significantly different to the photogrammetry approach. Validation of the flight height method using man-made objects of known dimensions and heights suggested a 9–18% error (3–6 m at ~ 30 m height). However, the profiles of mean flight height distribution matched patterns in previous work. This method was able to estimate the flying heights of 65% and 75% of flying gannets and kittiwakes, respectively, in this case study. The annual percentage of gannets at collision risk height for a set of turbines with a 30 m air gap was estimated at 29.8%, and 16.1% for kittiwake. This technique can greatly improve our knowledge of the spatial distribution of flight height patterns in marine ecosystems, but also allows stakeholders to assess collision risk more easily within the sphere of offshore wind for the consenting process. [ABSTRACT FROM AUTHOR]

Transcription and translation retrieve and operationalize gene encoded information in cells. These processes are not instantaneous and incur significant delays. In this paper we study Goodwin models of both inducible and repressible operons with state-dependent delays. The paper provides justification and derivation of the model, detailed analysis of the appropriate setting of the corresponding dynamical system, and extensive numerical analysis of its dynamics. Comparison with constant delay models shows significant differences in dynamics that include existence of stable periodic orbits in inducible systems and multistability in repressible systems. A combination of parameter space exploration, numerics, analysis of steady state linearization and bifurcation theory indicates the likely presence of Shilnikov-type homoclinic bifurcations in the repressible operon model. [ABSTRACT FROM AUTHOR]

Lethal bronzing disease is caused by the 16SrIV-D phytoplasma and is fatal to many palm species. This disease has caused significant economic losses to nursery and landscaping industries in Florida. As is the phloem-limited nature of phytoplasmas, the lethal bronzing disease phytoplasma is transmitted only by phloem-feeding insect vectors. However, the vector remains unconfirmed and this impedes the development of Integrated Pest Management programs that target vector populations. The primary objective of this study was to identify potential vectors of the 16SrIV-D phytoplasma in Florida by surveying auchenorrhynchans using sticky traps at the area where the disease is actively spreading, and screening the specimens for the presence of the phytoplasma. Cixiidae, Cicadellidae, Derbidae, and Membracidae insects were collected consistently during the 1-yr survey. The total number of a cixiid planthopper, Haplaxius crudus (Van Duzee) (Hemiptera: Cixiidae), was significantly higher than other insects that were collected on the traps. Of 3,734 specimens tested by nested polymerase chain reaction, approximately 0.672% of the H. crudus specimens and 1 unidentified leafhopper (Cicadellidae sp.) tested positive for the16SrIV-D phytoplasma. The 16S sequences amplified from the positive specimens were confirmed by sequencing and phylogenetic analysis. Based on the population survey and the polymerase chain reaction assay results, we suggest that H. crudus is the potential vector of the 16SrIV-D phytoplasma. However, the vector competency of H. crudus needs to be further investigated due to the possibility of feeding residue being detected. The study has important implication for current lethal bronzing disease management by monitoring and controlling vector candidates in disease areas. [ABSTRACT FROM AUTHOR]

In spite of the recent focus on the development of novel targeted drugs to treat cancer, cytotoxic chemotherapy remains the standard treatment for the vast majority of patients. Unfortunately, chemotherapy is associated with high hematopoietic toxicity that may limit its efficacy. We have previously established potential strategies to mitigate chemotherapy-induced neutropenia (a lack of circulating neutrophils) using a mechanistic model of granulopoiesis to predict the interactions defining the neutrophil response to chemotherapy and to define optimal strategies for concurrent chemotherapy/prophylactic granulocyte colony-stimulating factor (G-CSF). Here, we extend our analyses to include monocyte production by constructing and parameterizing a model of monocytopoiesis. Using data for neutrophil and monocyte concentrations during chemotherapy in a large cohort of childhood acute lymphoblastic leukemia patients, we leveraged our model to determine the relationship between the monocyte and neutrophil nadirs during cyclic chemotherapy. We show that monocytopenia precedes neutropenia by 3 days, and rationalize the use of G-CSF during chemotherapy by establishing that the onset of monocytopenia can be used as a clinical marker for G-CSF dosing post-chemotherapy. This work therefore has important clinical applications as a comprehensive approach to understanding the relationship between monocyte and neutrophils after cyclic chemotherapy with or without G-CSF support. [ABSTRACT FROM AUTHOR]

We develop and analyse a mathematical model of tumour–immune interaction that explicitly incorporates heterogeneity in tumour cell cycle duration by using a distributed delay differential equation. We derive a necessary and sufficient condition for local stability of the cancer-free equilibrium in which the amount of tumour–immune interaction completely characterizes disease progression. Consistent with the immunoediting hypothesis, we show that decreasing tumour–immune interaction leads to tumour expansion. Finally, by simulating the mathematical model, we show that the strength of tumour–immune interaction determines the long-term success or failure of viral therapy. [ABSTRACT FROM AUTHOR]

We explore the bifurcations and dynamics of a scalar differential equation with a single constant delay which models the population of human hematopoietic stem cells in the bone marrow. Oneparameter continuation reveals that with a delay of just a few days, stable periodic dynamics can be generated of all periods from about one week up to one decade! The long period orbits seem to be generated by several mechanisms, one of which is a canard explosion, for which we approximate the dynamics near the slow manifold. Two-parameter continuation reveals parameter regions with even more exotic dynamics including quasi-periodic and phase-locked tori, and chaotic solutions. The panoply of dynamics that we find in the model demonstrates that instability in the stem cell dynamics could be sufficient to generate the rich behavior seen in dynamic hematological diseases. [ABSTRACT FROM AUTHOR]

An accurate value for the first ionization potential of zirconium of 53 506.0(3) cm-1 has been obtained from convergence limits of high lying Rydberg series observed using two laser, field- ionization spectroscopy of an atomic beam of zirconium. The new value is consistent with analysis of s-electron binding energies of other second transition series elements. [ABSTRACT FROM AUTHOR]

We study a scalar delay differential equation (DDE) with two delayed feedback terms that depend linearly on the state. The associated constant-delay DDE, obtained by freezing the state dependence, is linear and without recurrent dynamics. With state-dependent delay terms, on the other hand, the DDE shows very complicated dynamics. To investigate this, we perform a bifurcation analysis of the system and present its bifurcation diagram in the plane of the two feedback strengths. It is organized by Hopf-Hopf bifurcation points that give rise to curves of torus bifurcation and associated two-frequency dynamics in the form of invariant tori and resonance tongues. We numerically determine the type of the Hopf-Hopf bifurcation points by computing the normal form on the center manifold; this requires the expansion of the functional defining the state-dependent DDE in a power series whose terms up to order three contain only constant delays. We implemented this expansion and the computation of the normal form coeffcients in Matlab using symbolic differentiation and the resulting code HHnfDDEsd is supplied as a supplement to this article. Numerical continuation of the torus bifurcation curves confirms the correctness of our normal form calculations. Moreover, it enables us to compute the curves of torus bifurcations more globally and to find associated curves of saddle-node bifurcations of periodic orbits that bound the resonance tongues. The tori themselves are computed and visualized in a three-dimensional projection, as well as the planar trace of a suitable Poincaré section. In particular, we compute periodic orbits on locked tori and their associated unstable manifolds (when there is a single unstable Floquet multiplier). This allows us to study transitions through resonance tongues and the breakup of a 1 : 4 locked torus. The work presented here demonstrates that state dependence alone is capable of generating a wealth of dynamical phenomena. [ABSTRACT FROM AUTHOR]

Despite their long-standing and central role in the dissemination, promotion and defense of science, scientific societies currently face a unique combination of economic, social and technological changes. As a result, one of the most pressing challenges facing many societies is declining membership due to reduced recruitment and a failure to retain members, particularly early-career scientists (ECSs). To ensure that professional biological societies retain long-term viability and relevance, the recruitment and retention of ECSs needs to be a main priority. Here we propose a series of recommendations that we, a group of ECSs, believe will help professional societies better integrate and retain ECSs. We discuss each recommendation and detail its implementation using examples from our personal experiences in the global seabird research and management communities and from our collective experience as members of several professional societies. We believe these recommendations will not only help recruit and retain ECSs as society members, but will also directly benefit the organizations themselves. [ABSTRACT FROM AUTHOR]

The choice of chemotherapy regimens is often constrained by the patient's tolerance to the side effects of chemotherapeutic agents. This dose-limiting issue is a major concern in dose regimen design, which is typically focused on maximising drug benefits. Chemotherapy-induced neutropenia is one of the most prevalent toxic effects patients experience and frequently threatens the efficient use of chemotherapy. In response, granulocyte colony-stimulating factor (G-CSF) is co-administered during chemotherapy to stimulate neutrophil production, increase neutrophil counts, and hopefully avoid neutropenia. Its clinical use is, however, largely dictated by trial and error processes. Based on up-to-date knowledge and rational considerations, we develop a physiologically realistic model to mathematically characterise the neutrophil production in the bone marrow which we then integrate with pharmacokinetic and pharmacodynamic (PKPD) models of a chemotherapeutic agent and an exogenous form of G-CSF (recombinant human G-CSF, or rhG-CSF). In this work, model parameters represent the average values for a general patient and are extracted from the literature or estimated from available data. The dose effect predicted by the model is confirmed through previously published data. Using our model, we were able to determine clinically relevant dosing regimens that advantageously reduce the number of rhG-CSF administrations compared to original studies while significantly improving the neutropenia status. More particularly, we determine that it could be beneficial to delay the first administration of rhG-CSF to day seven post-chemotherapy and reduce the number of administrations from ten to three or four for a patient undergoing 14-day periodic chemotherapy. [ABSTRACT FROM AUTHOR]

In this paper, the deformation mechanisms of a Fe–2.25%Cr–1%Mo (P22) steel are studied after tensile tests at room temperature (RT) and 550 °C (HT), creep-fatigue tests at 550 °C and stress relaxation test at 550 °C (HTSR). The RT, HT and HTSR tests produced permanent strain of about 2.5% by different processes. Deformation features such as the orientation of the grains, local misorientation, grain boundary type and distribution, etc., were characterized using electron backscatter diffraction. Transmission electron microscopy was done subsequently to obtain greater insight into the dislocation substructures. The as-received sample had a ferritic–bainitic microstructure, and a large amount of local misorientation was found in the bainite, indicating plastic strain due to phase transformation. After tensile strain to 2.5% at room temperature, the dislocations formed very small substructures (~100–200 nm) in the ferrite grains, and most of the retained plastic strain seemed to be concentrated in the bainite after deformation. Both the ferrite and bainite showed much lower local misorientation and dislocation wall content after a tensile test to 2.5% strain at 550 °C. Compared to the RT tensile sample, after creep-fatigue at 550 °C, the substructures in ferrite opened up considerably and formed small-angle grain boundaries, with clean areas as large as 20–25 μm. After stress relaxation at 550 °C, the ferrite displayed even less substructure, while the bainite seemed to have greater amounts of local misorientation than in the creep-fatigue case. However, the degree of misorientation was less pronounced than in the room temperature tensile case. These results have been discussed with respect to the causes behind the phenomena observed herein and their possible effects on mechanical behaviour. [ABSTRACT FROM AUTHOR]

The article presents letter to the Editor on the issue of upper bound for half-removal time of neutrophils from circulation in blood.

Aims To use open access models of predicted seabird distribution data in the Arctic to create rapid assessment biodiversity maps for management purposes and for prioritization of conservation. Location High Arctic, North of 60° latitude. Methods The predicted distributions of 27 species of Arctic seabirds were combined to create a seabird biodiversity map. The GIS layers created were based on peer-reviewed model outputs which were calculated using the random forest algorithm and supplemented with ISO standardized metadata for quality assurance. We have overlain the species diversity and occurrence maps with known shipping lanes and areas of human activities in the Arctic to highlight areas of potential human conflict with pelagic seabirds. Results Entry points to the Arctic Basin for example Baffin Bay, Davis Strait, Chukchi Sea, Greenland Sea and Norwegian Sea are specific conflict zones with mean number of species occurring within 20 km of shipping zones ranging from 17 to 19 (63-70% of modelled species). We also show that these are areas of the highest intensity of human activities in the Arctic (fishing, ship traffic and accident rates). Main conclusion These Arctic seabird biodiversity maps can be used to make decisions which take into account ecology and socio-economy (e.g. Marxan analysis and marine protected areas MPAs) and for ecological/economic studies which can help to create a pro-active management scheme. This is particularly important due to the future increase in human impacts in the Arctic (i.e. fishing, tourism and especially shipping). By improving upon these models and further examination into the interactions between seabirds and humans in the Arctic, we can guide important policy decisions to protect Arctic biodiversity. [ABSTRACT FROM AUTHOR]

Gamma distributed delay differential equations (DDEs) arise naturally in many modelling applications. However, appropriate numerical methods for generic gamma distributed DDEs have not previously been implemented. Modellers have therefore resorted to approximating the gamma distribution with an Erlang distribution and using the linear chain technique to derive an equivalent system of ordinary differential equations (ODEs). In this work, we address the lack of appropriate numerical tools for gamma distributed DDEs in two ways. First, we develop a functional continuous Runge–Kutta (FCRK) method to numerically integrate the gamma distributed DDE without resorting to Erlang approximation. We prove the fourth-order convergence of the FCRK method and perform numerical tests to demonstrate the accuracy of the new numerical method. Nevertheless, FCRK methods for infinite delay DDEs are not widely available in existing scientific software packages. As an alternative approach to solving gamma distributed DDEs, we also derive a hypoexponential approximation of the gamma distributed DDE. This hypoexponential approach is a more accurate approximation of the true gamma distributed DDE than the common Erlang approximation but, like the Erlang approximation, can be formulated as a system of ODEs and solved numerically using standard ODE software. Using our FCRK method to provide reference solutions, we show that the common Erlang approximation may produce solutions that are qualitatively different from the underlying gamma distributed DDE. However, the proposed hypoexponential approximations do not have this limitation. Finally, we apply our hypoexponential approximations to perform statistical inference on synthetic epidemiological data to illustrate the utility of the hypoexponential approximation. [ABSTRACT FROM AUTHOR]

We consider a bistable differential-difference equation with inhomogeneous diffusion. Employing a piecewise linear nonlinearity often referred to as McKean's caricature of the cubic, we construct front solutions which correspond, in the case of homogeneous diffusion, to monotone traveling front solutions or, in the case of propagation failure, to stationary front solutions. A general form for these fronts is given for essentially arbitrary inhomogeneous discrete diffusion, and conditions are given for the existence of solutions to the original discrete Nagumo equation. The specific case of one defect is considered in depth, giving a complete understanding of propagation failure and a grasp on changes in wave speed. Insight into the dynamic behavior of these front solutions as a function of the magnitude and relative position of the defects is obtained with the assistance of numerical results. [ABSTRACT FROM AUTHOR]

Dynamic Young’s modulus of a virgin and creep-damaged 2.25Cr–1Mo steel at high temperature has been evaluated non-destructively using the impulse excitation technique. The system developed to measure Young’s modulus at temperature in flexure mode is given. Young’s modulus-temperature relations are obtained providing useful information for structural analysis/design. [Copyright &y& Elsevier]

Variable time-stepping algorithms for initial value ordinary differential equations are traditionally designed to solve a problem for a fixed initial condition and over a finite time. It can be shown that these algorithms may perform poorly for long time computations with initial conditions that lie in a small neighborhood of a fixed point. In this regime there are orbits that are bounded in space but unbounded in time, and the classical error-per-step or error-per-unit-step philosophy may be improved upon. A new error criterion is introduced that essentially bounds the truncation error at each step by a fraction of the solution arc length over the corresponding time interval. This new control can be incorporated within a standard algorithm as an additional constraint at negligible additional computational cost. It is shown that this new criterion has a positive effect on the linear stability properties and hence improves behavior in the neighborhood of stable fixed points. Furthermore, spurious fixed points and period two solutions are prevented. The new criterion is shown to be admissible in the sense that it can always be satisfied with nonzero stepsizes. Implementation details and numerical results are given. [ABSTRACT FROM AUTHOR]

We consider the finite element solution of the parameterized semilinear elliptic equation Δu + λu + u5 = 0,u > 0, where u is defined in the unit cube and is 0 on the boundary of the cube. This equation is important in analysis, and it is known that there is a value λ0 > 0 such that no solutions exist for λ < λ0. By solving a related linear equation we obtain an upper bound for λ0 which is also conjectured to be an estimate for its value. We then present results on computations on the full nonlinear problem. Using formal asymptotic methods we derive an approximate description of u which is supported by the numerical calculations. The asymptotic methods also give sharp estimates both for the error in the finite element solution when λ > λ0 and for the form of the spurious numerical solutions which are known to exist when λ < λ0. These estimates are then used to post-process the numerical results to obtain a sharp estimate for λ0 which agrees with the conjectured value.

Traditional methods to assess population size in seabirds are applicable only to species that nest in visible locations, leaving cryptic nocturnal, burrow-nesting seabirds underrepresented in typical long-term population monitoring programs. Alternative methods to count burrow-nesting birds, however, are extremely labor-intensive and therefore are applicable only to small and possibly unrepresentative areas, and may have negative effects on burrow-nesting populations. We suggest the use of automatic acoustic recorders as a possible survey technique to overcome logistic difficulties of research of seabirds on remote islands in the Republic of Korea, where funding for ecological research is extremely limited but where globally important seabird colonies exist. In this study, we used automated acoustic recorders to model the relationship between call activity and known abundance of the Streaked Shearwater Calonectris leucomelas at sites on Sasu Island, the largest breeding colony that exists in Korea, supplemented by data from the closely related Cory's Shearwater C. borealis. Based on a positive relationship between breeding burrow density and call activity, we cautiously estimated the population size of the Streaked Shearwaters to be 95-278 pairs at another breeding colony on Chilbal Island. Although this method may not be precise enough to estimate the exact population size of a seabird species at a location, it can provide coarse estimates that can be used to track relative changes over time. [ABSTRACT FROM AUTHOR]

We study boundary value differential-difference equations where the difference terms may contain both advances and delays. Special attention is paid to connecting orbits, in particular to the modeling of the tails after truncation to a finite interval, and we reformulate these problems as functional differential equations over a bounded domain. Connecting orbits are computed for several such problems including discrete Nagumo equations, an Ising model, and Frenkel--Kontorova type equations. We describe the collocation boundary value problem code used to compute these solutions, and the numerical analysis issues which arise, including linear algebra, boundary functions and conditions, and convergence theory for the collocation approximation on finite intervals. [ABSTRACT FROM AUTHOR]

This paper summarises our recent investigations undertaken as part of the EURODESAL project on nuclear desalination, currently being carried out by a consortium of four European, and one Canadian, industrials and two leading EU R&D organisations.Major achievements of the project, as discussed in this paper are:

Children with spastic diplegia as a result of cerebral palsy (CP) or HIV encephalopathy have different pathogenesis but present with similar motor deficits. Anti-retroviral therapy has allowed HIV-infected children to survive for longer but with this comes an increase in co-morbid complications that are not life-threatening but have an adverse effect on activity and participation. The aim of this study was to determine if there are similarities or differences with regards to function, tone and strength between children with spastic diplegia as a result of CP and those with spastic diplegia as a result of HIV encephalopathy. Participants with spastic diplegia (GMFCS I to IV) between the ages of 4 and 16 years were selected at four institutions in Johannesburg. Thirty-three HIV-infected children with spastic diplegia and 31 HIV-uninfected participants with CP spastic diplegia were assessed using the Gross Motor Function Measure 66 (GMFM-66), Functional Mobility Scale (FMS), Modified Ashworth Scale (MAS) for tone, and a hand-held dynamometer for strength. There were no statistically significant differences between the two groups with respect to function, strength and tone. When the groups were separated into ambulant (GMFCS I and II) and non-ambulant groups (GMFCS III and IV), there were no statistically significant differences between the two groups for GMFM (ambulant group p = 0.52, non-ambulant group p = 0.74), tone and strength. A minimally clinically important difference (MCID = 3.87) was found for the GMFM-66 in the ambulant group in favour of the HIV-infected participants. There was a trend for the HIV-infected ambulant participants to be weaker and have milder tone from proximal to distal. The non-ambulant HIV-infected participants tended to be stronger and have mild rather than severe tone from proximal to distal when compared to the CP group. Children with spastic diplegia as a result of HIV encephalopathy presented similarly to the HIV-uninfected children with spastic diplegic CP but tended to be more functional, have less severe tone and were weaker. [ABSTRACT FROM AUTHOR]

UV and visible multiphoton dissociation (MPD) processes of Ga(CH3)3 have been investigated by time-resolved detection of Ga(4 2PJ ) (J=1/2, 3/2) and Ga(5 2S1/2) following pulsed laser photolysis in a low pressure gas cell, and by mass spectrometric detection of ionic photofragments in a molecular beam. The relative abundances of neutral and ionic fragments were monitored as a function of photolysis wavelength and flux. Measurements of the anisotropy of the velocity distribution and the average kinetic energy of nascent Ga(4 2PJ ) are also reported. Under conditions of moderate photolysis flux ([bar_over_tilde:_approx._equal_to]108 W cm-2), MPD of Ga(CH3)3 in the wavelength range 420–520 nm produced mainly neutral fragments, including Ga(4 2PJ ) and a metastable molecular fragment which is identified as GaCH3. Photolysis at 222 nm produced GaCH3 to the exclusion of Ga(4 2PJ ), or primarily ionic fragments at relatively high flux. At 308 nm, ionic Ga(CH3)+n species were produced in relatively high yield even in the limit of low photolysis flux. The mechanisms of MPD and MPI of Ga(CH3)3 are discussed with reference to simple rate equations models. [ABSTRACT FROM AUTHOR]

There is high interest in understanding the mechanisms that drive self-renewal of stem cells. HOXB4 is one of the few transcription factors that can amplify long-term repopulating hematopoietic stem cells in a controlled way. Here we show in mice that this characteristic of HOXB4 depends on a proline-rich sequence near the N terminus, which is unique among HOX genes and highly conserved in higher mammals. Deletion of this domain substantially enhanced the oncogenicity of HOXB4, inducing acute leukemia in mice. Conversely, insertion of the domain into Hoxa9 impaired leukemogenicity of this homeobox gene. These results indicate that proline-rich stretches attenuate the potential of stem cell active homeobox genes to acquire oncogenic properties. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented regarding the cis-regulatory elements of myeloid ecotropic viral integration site 1 (MEIS1) in hematopoietic cells.

Objectives The aim of this study was to evaluate the HIV-1 RNA pooled nucleic acid amplification testing (NAAT) strategy to screen pregnant women in the 'window period' of acute HIV infection (AHI) in rural South Africa. Methods In 2007 and 2008, 750 consecutive pregnant women on their first antenatal care visit to a primary health care clinic were tested anonymously for HIV infection. HIV-1 RNA pooled NAAT was performed on HIV antibody-negative samples. All positive pools were tested individually and positive samples were classified as incident cases to calculate HIV incidence. Results The overall HIV prevalence was 37.3% [95% confidence interval (CI) 34.3-41.3]. Of the 467 HIV antibody-negative samples, four (0.9%) were HIV-1 RNA-positive. The mean viral load in the four samples was 386 260 HIV-1 RNA copies/mL (range 64 200-1 228130). The HIV incidence was 11.2% per year (95% CI 0.3-22.1) and all women with AHI were ≤21 years of age. Conclusions Identifying AHI in pregnancy is important for health interventions to reduce perinatal and heterosexual transmission of HIV, and to estimate HIV incidence for epidemiological surveillance. [ABSTRACT FROM AUTHOR]

Illustrates the results of differential equations organized on a spatial lattice in a form analogous to the Cahn-Hilliard partial differential equation by means of numerical simulations. Existence and uniqueness proof for initial value problem and the stability of mosaic equilibrium solutions; Differences between Allen-Cahn and Cahn-Hilliard equations; General entropy calculations.

Simple Summary: Phytopathogen-induced changes often affect insect vector feeding behavior and potentially pathogen transmission. The impacts of pathogen-induced plant traits on vector preference are well studied in pathosystems but not in phytoplasma pathosystems. Therefore, the study of phytoplasma pathosystems may provide important insight into controlling economically important phytoplasma related diseases. In this study, we aimed to understand the impacts of a phytoplasma disease in palms on the feeding preference of its potential vector. We investigated the effects of a palm-infecting phytoplasma, lethal bronzing (LB), on the abundance of herbivorous insects. These results showed that the potential vector, Haplaxius crudus, is more abundant on LB-infected than on healthy palms. In contrast, other insects are more abundant on healthy over infected-palms or have no difference between the infection status of palms. Additionally, we further examined the impacts of LB, palm height, temperature, and their interactive effects on H. crudus abundance, and the results revealed significant interactive effects of these factors on H. crudus abundance. These results suggest the involvement of multiple biotic and abiotic factors influencing vector preference. The results of the interactive impacts of phytoplasma, palm height, and temperature on vector preference in natural settings provide useful information for optimizing vector monitoring and disease management strategies. Insect vector feeding preference and behavior play important roles in pathogen transmission, especially for pathogens that solely rely on insect vector transmission. This study aims to examine the effects of the 16SrIV-D phytoplasma, the causal agent of lethal bronzing (LB) disease of palms, on associated auchenorrhynchan insects. The numbers of auchenorrhynchans collected during weekly surveys during a yearlong study using yellow sticky traps were analyzed. The cumulative number of H. crudus was 4.5 times greater on phytoplasma-infected relative to non-infected palms. Other auchenorrhynchans showed no difference between phytoplasma-infected and non-infected palms or were greater on non-infected rather than on infected palms. Furthermore, we examined the effects of LB, palm height, temperature, and the interactive effects of these factors on H. crudus abundance. When the palms were infected with LB, at low temperature, H. crudus was more abundant on shorter than taller palms; however, H. crudus was more abundant on taller than shorter palms at the median and higher temperatures. These results may indicate that H. crudus prefers LB-infected palms over non-infected palms. The interactive effects of LB, palm heights, and temperature further suggest that vector monitoring and disease management should be optimized according to seasonal variation in temperature. [ABSTRACT FROM AUTHOR]