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Invertebrates are a neglected but important component of urban ecosystems. Although cities are a heterogeneous landscape most studies of urban invertebrates focus on specific habitat fragment types. We modeled the resource selection of an undescribed species of Onychophora – the Dunedin peripatus – at multiple scales across an urban gradient in the city of Dunedin, New Zealand. We aimed to identify habitat variables that influence the presence of the species in a modified urban environment, to assist in management strategies focused on conserving Onychophora as a phylum. We modeled resource selection at micro-and macro-scales within selected parks and habitat fragments using resource selection probability functions (RSPF), and using maximum entropy (Maxent) models at the landscape-scale. We identified 12 relevant environmental variables within habitat fragments and the surrounding urban matrix. The Dunedin peripatus was positively associated with shaded, moist sites with an abundance of large decayed cover objects, including living native tree fuchsia ( Fuchsia excorticata ) and downed woody material. Dunedin peripatus persisted in fragments dominated by exotic vegetation and a history of disturbance, including urban gardens and forest plantations, although the period between disturbances necessary to maintain peripatus populations remains unclear. Our results highlight the importance of studying habitat use at multiple scales within urban areas for biodiversity conservation proposes, even for relatively sessile invertebrates such as onychophorans. We also demonstrate the need for researching and conserving Onychophora populations in terrain that is traditionally discounted as being inhospitable due to disturbance. [ABSTRACT FROM AUTHOR]

We prove the existence and uniqueness of solutions of a class of weakly non-linear wave equations in a semi-infinite region $0le x$, $t< L/sqrt{|epsilon|}$ under arbitrary initial and boundary conditions. We also establish the asymptotic validity of formal perturbation approximations of the solutions in this region.

This theoretical essay aims to study how scales are developed and through which procedures they can be considered valid and suitable for use as legitimate scientific instruments. In this perspective, this paper's objective was to develop a protocol for constructing scales to measure attitude. The proposed protocol is configured as a logical meeting of steps based on theorists such as Allport and Hartman (1925), Thurstone (1928), Likert (1932), Campbell and Fiske (1959) and Bock (1972), which permeate all aspects of drafting scales, including construct definition, the choice of the scale itself, item preparation, scale purification, and finally its validation. At the end of the study, we present a protocol for the preparation of specific scales to measure attitude that differs from existing protocols in Churchill (1979), Rossiter (2002) and DeVellis (2003). This is in order to unite for the first time a set of promising techniques, primarily the objective delineation of the construct using focus group methodology, the proposition of an inherently dichotomous scale, scale purification via item response theory (IRT), and predictive validity. [ABSTRACT FROM AUTHOR]

We formulate a multi-scale perturbation technique to asymptotically solve weakly nonlinear hyperbolic equations. The method is based on a set of scaled characteristic coordinates. We show that this technique leads to a simplified system of ordinary differential equations describing the weakly nonlinear interaction between left and right running waves. Using this method, a uniformly valid first order solution of a prototype nonlinear equation is derived.

Increasing studies worldwide have examined the impacts of urban forests on mitigating atmospheric particulate matter (PM) over the past decades. These scattered studies revealed the aerodynamics of atmospheric PM deposited on urban forests, as well as the various factors influencing the PM capture and removal by urban forests. However, these evidences are varying and even contradictory, and the affecting factors do not follow a universal pattern. In addition, these studies generally have been conducted in a specific scale such as leaf, stand and city without considering the multi-scale associations and incorporations. This literature review tried to address the associations of urban forest and PM removal across single tree, stand and regional scales, and summarized the confounding factors for PM capture and removal within each scale. Particle size and local meteorology have significant impacts across scales. For an individual tree, PM capture and removal capacity are largely determined by the leaf morphology and epidermal structures, but at the stand scale, the biophysical characteristics and configurational designs of urban forests are the essential factors. At the city and regional scale, the determinants are the fraction of forest coverage, as well as background pollution levels. The literature collation emphasizes the necessity of concerning the appropriate factors responding to the specific scale when quantifying and evaluating PM capture and removal by urban forests, and warrants a multi-scale research paradigm and inclusive modeling evaluation incorporating the confounding factors from multiple scales for PM capture and removal by urban forests. • The multi-scale interactions between urban forest and PM capture and removal were reviewed. • Local climate and meteorology are the main drivers through tree, stand and regional scales. • The vegetation-related parameters for PM capture and removal vary and dependent across scales. • Epidermal structures are concerned for tree scale, bio-physicals for stand scale, and surface areas for region scale. • A research paradigm integrating confounding factors and multiple scales should be established. [ABSTRACT FROM AUTHOR]

Wrist dislocations can occur from the tearing of ligaments in the wrist. In order for the wrist to heal, surgery is often performed. During the post-operative healing process the repaired ligament will stretch causing the range of motion of the wrist to vary with time. To better understand this healing process, a mathematical model that treats the wrist as an oscillator is introduced. A corresponding weakly nonlinear differential equation is investigated using perturbation methods and an asymptotic approximation of the solution is found. A numerical solution to the model is then compared to the asymptotic approximation under various parameter regimes. [ABSTRACT FROM AUTHOR]

In this paper we re-visit the Lagerstrom problemy" + (n-1)/r y' + εyy' = 0,y(1) = 0, y(∞) = 1,where ε is a small positive real number and n is a positive integer (or any real number greater than 2). Using rigorous analysis, a generalized asymptotic expansion, as ε→0, is derived for the solution of this problem. A trans-series expansion of the solution for large values of r is also presented; the leading term coefficient is determined by a connection formula between the values of the solution at the two points r=1 and r=∞. An extension and a discussion of the problem for n∈[1,2) is also given. [ABSTRACT FROM AUTHOR]

Compute Unified Device Architecture (CUDA) is a parallel computing platform and programming model invented by NVIDIA. It enables dramatic increase in computing performance via the power of the graphics processing unit (GPU). In medical image analysis, 3D image registration generally takes relatively long time, which is not feasible for clinical applications. To solve this problem, this paper proposed a high performance computational method based on CUDA, which took full advantage of GPU parallel computing under CUDA architecture combined with image multiple scale and maximum mutual information. Experiments showed that this algorithm can not only maintain the registration accuracy but also greatly increase the speed of registration process and meet the real-time requirement of clinical application. [ABSTRACT FROM AUTHOR]

Spatiotemporal periodic patterns, including phase-locked oscillations, mirror-reflecting waves, standing waves, in-phase or anti-phase oscillations are investigated in a ring of bidirectionally coupled oscillators with neutral delay feedback. It is confirmed that neutral feedback makes Hopf bifurcation occur in a larger domain of parameters. We calculate the normal forms near Hopf bifurcation, D equivariant Hopf bifurcation and double-Hopf bifurcation in this neutral equation by using the method of multiple scales. Theoretically, the appearance of the in-phase, anti-phase and phase-locked oscillations that we observed in the simulation about a ring of delay coupled Hindmarsh-Rose neurons with neutral feedback is explained. [ABSTRACT FROM AUTHOR]

We study the appearance and stability of spatiotemporal periodic patterns like phase-locked oscillations, mirror-reflecting waves, standing waves, in-phase or antiphase oscillations, and coexistence of multiple patterns, in a ring of bidirectionally delay coupled oscillators. Hopf bifurcation, Hopf-Hopf bifurcation, and the equivariant Hopf bifurcation are studied in the viewpoint of normal forms obtained by using the method of multiple scales which is a kind of perturbation technique, thus a clear bifurcation scenario is depicted. We find time delay significantly affects the dynamics and induces rich spatiotemporal patterns. With the help of the unfolding system near Hopf-Hopf bifurcation, it is confirmed in some regions two kinds of stable oscillations may coexist. These phenomena are shown for the delay coupled limit cycle oscillators as well as for the delay coupled chaotic Hindmarsh-Rose neurons. [ABSTRACT FROM AUTHOR]

In the area of mechanics and electronics, the behaviors of mechanical systems under periodic loadings have been examined by many researchers. Vertical conveyors are effective examples observing various kinds of parameters of this problem. In this study, primary, subharmonic, and superharmonic responses have been investigated with multiple scales along with numerical methods for vertical conveyors. The change in the parameters of motion, stability condition, and jump phenomena has been shown graphically by Mathematica software for comparing the results. Both analytical and numerical results obtained had good agreement. [ABSTRACT FROM AUTHOR]

Compute Unified Device Architecture (CUDA) is a parallel computing platform and programming model invented by NVIDIA. It enables dramatic increase in computing performance via the power of the graphics processing unit (GPU). In medical image analysis, 3D image registration generally takes relatively long time, which is not feasible for clinical applications. To solve this problem, this paper proposed a high performance computational method based on CUDA, which took full advantage of GPU parallel computing under CUDA architecture combined with image multiple scale and maximum mutual information. Experiments showed that this algorithm can not only maintain the registration accuracy but also greatly increase the speed of registration process and meet the real-time requirement of clinical application. [ABSTRACT FROM AUTHOR]

In this paper we use a Renormalization Group (RG) method to study the long-time asymptotics of nonlinear diffusion equations with time-dependent diffusion coefficients and nonlinearities which are marginal (or critical) with respect to the RG operator. These equations describe the time evolution of the average concentration of a passive scalar being advected by a random velocity field. We prove that, besides the expected diffusive behavior, there is an extra logarithmic correction which is the imprint of the critical nonlinearity. [ABSTRACT FROM AUTHOR]

We present a multiple scale approach for modeling multiple crack growth in human cortical bone under tension. The Haversian microstructure, a four phase composite, is discretized by a classical finite element method fed with the morphological and mechanical characteristics, experimentally measured, to mimic human bone heterogeneity at the micro scale. The fracture strength of human bone, exhibiting aging signs, is investigated through tensional percolation simulations in statistical microstructures. The cracks are initiated at the micro scale at locations where a critical elastic-damage strain-driven criterion is met. The cracks, modeled by the eXtended Finite Element Method, are then grown until complete failure when a critical stress intensity factor criterion is attained. The model provides the fracture strength and the global response at the material scale and the stress–strain fields at the microscopic level. The model creates a constitutive law at the material scale and emphasizes the influence of the microstructure on bone failure and fracture risk assessment. These results are validated against experiments. [ABSTRACT FROM AUTHOR]

Abstract: This note generalizes an earlier suggested simple example of a trapped mode in a linearly elastic waveguide. A semi-infinite string with a point end mass is considered in the presence of a weakly non-linear support. The effect of non-linearity involves small amplitude non-localized disturbances resulting in a slow time-decay of the vibration amplitude. The rate of the decay is evaluated along with the correction to the vibration phase using the method of multiple scales. To cite this article: J. Kaplunov, E. Nolde, C. R. Mecanique 336 (2008). [Copyright &y& Elsevier]

Copyright of Avian Conservation & Ecology is the property of Resilience Alliance and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Avian Conservation & Ecology is the property of Resilience Alliance and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Global biodiversity decline has prompted great interest in the effects of habitat modification and diversity on the functioning and stability of ecosystem processes. However, the applicability of previous modeled or mesocosm community studies to real diverse communities in different habitats remains ambiguous. We exposed standardized nesting resources for naturally occurring communities of cavity-nesting bees and wasps and their parasitoids in coastal Ecuador, to test the effects of host and parasitoid diversity on an ecosystem function (parasitism rates) and temporal variability in this function. In accordance with predictions of complementary host use, parasitism rates increased with increasing diversity, not simply abundance, of parasitoids. In contrast, parasitism decreased with increasing host diversity, possibly due to positive prey interactions or increased probability of selecting unpalatable species. Temporal variability in parasitism was lower in plots with high mean parasitoid diversity and higher in plots with temporally variable host and parasitoid diversity. These effects of diversity on parasitism and temporal stability in parasitism rates were sufficiently strong to be visible across five different habitat types, representing a gradient of increasing anthropogenic modification. Habitat type did not directly affect parasitism rates, but host and parasitoid diversity and abundance were higher in highly modified habitats, and parasitoid diversity was positively correlated with rates of parasitism. The slope of the richness-parasitism relationship did not vary significantly across habitats, although that for Simpson's diversity was significant only in rice and pasture. We also show that pooling data over long time periods, as in previous studies, can blur the effect of diversity on parasitism rates, and the appropriate spatiotemporal scale of study must be considered. [ABSTRACT FROM AUTHOR]

Abstract: Macroscopic descriptions of instability pattern formation can be obtained by the generic amplitude equations of Ginzburg–Landau type. In the simple example of beam buckling, a variant of this approach is established, that permits one to account for the coupling between local and global instabilities. The mean field and the amplitude of the fluctuations are governed by similar equations. The resulting model is a generalized continuum, where the generalized stresses are Fourier coefficients of the microscopic stress. To cite this article: N. Damil, M. Potier-Ferry, C. R. Mecanique 334 (2006). [Copyright &y& Elsevier]

In this study, we use perturbation approximations and semiclassical methods to investigate the boundary solutions of non-linear vibrating systems. The extended Mathieu Equation, related to the perturbed Van der Pol oscillator with periodic coefficients, is solved using multiple time scales. Then, using the Von Zeipel Method which is based on the Hamilton-Jacobi theory, stability conditions are presented. It is shown that the stability boundaries are the same with those obtained by both methods. [ABSTRACT FROM AUTHOR]

Restoration should be a part of an overall strategy for national, regional and local land management, rather than an independent action. A hierarchically structured approach for restoration is examined by introducing actual policy and work for reestablishment of natural forest in Tokushima Prefecture, Shikoku, Japan. The goal set by Tokushima Prefectural Government is to increase the quality of biotope for indigenous plants and animals through increasing the area of natural and semi-natural vegetation and their connectivity. A “networking map” indicating high priority areas to be conserved or to be restored has been produced, using Natural Environment GIS provided by the Ministry of Environment of Japan. Having the estimated distribution of natural forests is helpful for selecting the targets for restoration, because natural forests have already disappeared from most regions due to land development. For reforestation at the cutover site, a method for designing work was developed. In order to select species and plan planting zones, ecotope types were identified both in natural forest as a reference and at the cutover site. A system for supplying indigenous seedlings was established. [ABSTRACT FROM AUTHOR]

We prove the existence and uniqueness of solutions of a class of weakly non-linear wave equations in a semi-infinite region 0 ≤ x, t < L/√|∈|under arbitrary initial and boundary conditions. We also establish the asymptotic validity of formal perturbation approximations of the solutions in this region. [ABSTRACT FROM AUTHOR]

This work is concerned with asymptotic properties of solutions to forward equations for singularly perturbed Markov chains with two small parameters. It is motivated by the model of a cost-minimizing firm involving production planning and capacity expansion and a two-level hierarchical decomposition. Our effort focuses on obtaining asymptotic expansions of the solutions to the forward equation. Different from previous work on singularly perturbed Markov chains, the inner expansion terms are constructed by solving certain partial differential equations. The methods of undetermined coefficients are used. The error bound is obtained. [Copyright &y& Elsevier]

Changes in mature forest cover amount, composition, and configuration can be of significant consequence to wildlife populations. The response of wildlife to forest patterns is of concern to forest managers because it lies at the heart of such competing approaches to forest planning as aggregated vs. dispersed harvest block layouts. In this study, we developed a species assessment framework to evaluate the outcomes of forest management scenarios on biodiversity conservation objectives. Scenarios were assessed in the context of a broad range of forest structures and patterns that would be expected to occur under natural disturbance and succession processes. Spatial habitat models were used to predict the effects of varying degrees of mature forest cover amount, composition, and configuration on habitat occupancy for a set of 13 focal songbird species. We used a spatially explicit harvest scheduling program to model forest management options and simulate future forest conditions resulting from alternative forest management scenarios, and used a process-based fire-simulation model to simulate future forest conditions resulting from natural wildfire disturbance. Spatial pattern signatures were derived for both habitat occupancy and forest conditions, and these were placed in the context of the simulated range of natural variation. Strategic policy analyses were set in the context of current Ontario forest management policies. This included use of sequential time-restricted harvest blocks (created for Woodland caribou (Rangifer tarandus) conservation) and delayed harvest areas (created for American marten (Martes americana atrata) conservation). This approach increased the realism of the analysis, but reduced the generality of interpretations. We found that forest management options that create linear strips of old forest deviate the most from simulated natural patterns, and had the greatest negative effects on habitat occupancy, whereas policy options that specify deferment and timing of harvest for large blocks helped ensure the stable presence of an intact mature forest matrix over time. The management scenario that focused on maintaining compositional targets best supported biodiversity objectives by providing the composition patterns required by the 13 focal species, but this scenario may be improved by adding some broad-scale spatial objectives to better maintain large blocks of interior forest habitat through time.

Conservation of biodiversity is now a firmly entrenched objective of sustainable forest management, and emulating natural disturbance has been widely adopted as a conservation strategy. Yet the foundation for this approach is still very much a hypothesis based on first principles, and there has been little rigorous testing of the approach. In addition, practical constraints mean that the full range and character of natural patterns can never be implemented, so decisions must still be made in setting forest management targets and levels. An alternative, but complementary approach is to select a focal group of species and use their habitat requirements to define the range of conditions that should be maintained on the landscape. In this study, I used a balanced factorial sample design to test the effect of landscape vs. local scale factors for explaining relative abundance of 30 forest songbird species in boreal Ontario, and then examined components of variance, and used multivariate analysis and logistic regression to describe these relationships in more detail. Based on statistically defendable inferences and habitat model coefficients, 13 species were selected, with habitat associations ranging from high to low edge density, homogeneous to heterogeneous forest matrix, hardwood to softwood dominated overstory, young to old stands, and open to closed canopy. I found that variations in amount and configuration of mature forest cover had relatively little influence on the overall boreal forest songbird community, but that individual species differ in their response to these variables. To be successful, biodiversity conservation strategies must emulate the patterns created through natural disturbance by maintaining the full range of forest cover homogeneity and heterogeneity on the landscape. The habitat requirements for Alder Flycatcher, Black-and-white Warbler, Bay-breasted Warbler, Blackburnian Warbler, Brown Creeper, Common Yellowthroat, Chestnut-sided Warbler, Least Flycatcher, Ovenbird, Red-breasted Nuthatch, Red-eyed Vireo, Winter Wren, and White-throated Sparrow describe a broad range of habitat conditions that, at a minimum, describe necessary coarse-filter conditions to sustain the boreal songbird community in Ontario. This suite of species can also serve in developing a "bioassay" to evaluate the effectiveness of forest policy to conserve biodiversity through emulation of natural disturbance.

• We propose a multi-scale image processing method to facilitate and assist the reliable segmentation of liver cancer area in Whole Slide Image (WSI). • We use a method of partial color normalization for equalizing the color representation of different tissue areas. • We adapt a weighted overlapping method to overcome the loss of border information resulted by cropping operation. • We propose a voting mechanism to integrate multi-scale information by multiple validation to get the optimal final result. This paper addresses the problem of liver cancer segmentation in Whole Slide Images (WSIs). We propose a multi-scale image processing method based on an automatic end-to-end deep neural network algorithm for the segmentation of cancerous areas. A seven-level gaussian pyramid representation of the histopathological image was built to provide the texture information at different scales. In this work, several neural architectures were compared using the original image level for the training procedure. The proposed method is based on U-Net applied to seven levels of various resolutions (pyramidal subsampling). The predictions in different levels are combined through a voting mechanism. The final segmentation result is generated at the original image level. Partial color normalization and the weighted overlapping method were applied in preprocessing and prediction separately. The results show the effectiveness of the proposed multi-scale approach which achieved better scores than state-of-the-art methods. [ABSTRACT FROM AUTHOR]

The use of multibeam echosounder systems (MBES) for detailed seafloor mapping is increasing at a fast pace. Due to their design, enabling continuous high-density measurements and the coregistration of seafloor's depth and reflectivity, MBES has become a fundamental instrument in the advancing field of acoustic seafloor classification (ASC). With these data becoming available, recent seafloor mapping research focuses on the interpretation of the hydroacoustic data and automated predictive modeling of seafloor composition. While a methodological consensus on which seafloor sediment classification algorithm and routine does not exist in the scientific community, it is expected that progress will occur through the refinement of each stage of the ASC pipeline: ranging from the data acquisition to the modeling phase. This research focuses on the stage of the feature extraction; the stage wherein the spatial variables used for the classification are, in this case, derived from the MBES backscatter data. This contribution explored the sediment classification potential of a textural feature based on the recently introduced Weyl transform of 300 kHz MBES backscatter imagery acquired over a nearshore study site in Belgian Waters. The goodness of the Weyl transform textural feature for seafloor sediment classification was assessed in terms of cluster separation of Folk's sedimentological categories (4-class scheme). Class separation potential was quantified at multiple spatial scales by cluster silhouette coefficients. Weyl features derived from MBES backscatter data were found to exhibit superior thematic class separation compared to other well-established textural features, namely: (1) First-order Statistics, (2) Gray Level Co-occurrence Matrices (GLCM), (3) Wavelet Transform and (4) Local Binary Pattern (LBP). Finally, by employing a Random Forest (RF) categorical classifier, the value of the proposed textural feature for seafloor sediment mapping was confirmed in terms of global and by-class classification accuracies, highest for models based on the backscatter Weyl features. Further tests on different backscatter datasets and sediment classification schemes are required to further elucidate the use of the Weyl transform of MBES backscatter imagery in the context of seafloor mapping. [ABSTRACT FROM AUTHOR]

Jaguars (Panthera onca), like other apex predators, are highly susceptible to habitat loss and fragmentation given their low demographic potential and large habitat area requirements. Across their range, the Pantanal is considered critical for the jaguar's long-term conservation. Here we provide the first multi-scale path selection function model for jaguars, and the first empirically-based movement model covering the entire Pantanal ecosystem. Out of eight investigated variables, six were related to jaguar habitat use in the Pantanal: terrain roughness, human population density, grassland, percentage of tree cover, flooded habitats and shrubland. The results of scale optimization revealed that jaguars responded primarily to landscape variables at broad scales (32 km) of habitat availability, with only one variable (grassland) influencing jaguar path selection at a finer scale (4 km). Jaguar habitat use was positively associated with flooded habitats and densely forested areas and negatively associated with grassland, terrain roughness, and human population density, with the latter having the strongest negative effect on jaguar movement. The prediction map suggested that only 9.3% of the total suitable jaguar habitat in Pantanal is protected by Conservation Units. Among the most suitable areas, the largest continuous habitats were located in the northwestern portions of the Pantanal, which corresponds to the interfluvial areas between Corixo Grande and Cuiaba rivers. Our results suggested that the implementation of already proposed North Pantanal Conservation Unit Mosaic in this area would be highly valuable for jaguar conservation. This study provides a foundation for future research to delineate and prioritize core areas and corridors for jaguars in the region. [ABSTRACT FROM AUTHOR]

Despite an advanced ability to forecast ecosystem functions and climate at regional and global scales, little is known about relationships between local variations in water and carbon fluxes and large-scale phenomena. To enable data collection of local-scale ecosystem functions to support such investigations, we developed the EcoSpec system, a highly equipped remote sensing system that houses a hyperspectral radiometer (350–2500 nm) and five optical and infrared sensors in a compact tower. Its custom software controls the sequence and timing of movement of the sensors and system components and collects measurements at 12 locations around the tower. The data collected using the system was processed to remove sun-angle effects, and spectral vegetation indices computed from the data (i.e., the Normalized Difference Vegetation Index (NDVI), Normalized Difference Water Index (NDWI), Photochemical Reflectance Index (PRI), and Moisture Stress Index (MSI)) were compared with the fraction of photochemically active radiation (fPAR) and canopy temperature. The results showed that the NDVI, NDWI, and PRI were strongly correlated with fPAR; the MSI was correlated with canopy temperature at the diurnal scale. These correlations suggest that this type of near-surface remote sensing system would complement existing observatories to validate satellite remote sensing observations and link local and large-scale phenomena to improve our ability to forecast ecosystem functions and climate. The system is also relevant for precision agriculture to study crop growth, detect disease and pests, and compare traits of cultivars. [ABSTRACT FROM AUTHOR]