Real Boundaries Research Articles

Toward the multi-component quantum theory of atoms in molecules: a variational derivation

The general formalism of an extended quantum theory of atoms in molecules (QTAIM) dealing with the multi-component quantum systems, composed of various types of quantum particles, is disclosed in this contribution. This novel methodology, termed as the multi-component QTAIM (MC-QTAIM), is able to deal with non-adiabatic ab initio wavefunctions extracting atoms in molecules quantifying their properties. It can also be applied to elucidate the AIM structure of exotic species and bound quantum systems consisting of fundamental elementary particles like positrons and muons. The formalism is based on the previously disclosed density combination idea that is extended to derive the multi-component subsystem hypervirial theorem as well as the extended subsystem energy functional. Through the extended subsystem variational procedure, inspired from Schrodinger’s original variational principle, the surface terms containing the flux of the current property densities are derived. Accordingly, the extended Gamma field is introduced during this variational procedure that is used as the basic scalar field in the topological analysis yielding atoms in molecules and their real space boundaries. The Gamma field is central to the MC-QTAIM, replacing the usual one-electron density employed in the orthodox QTAIM and corresponding topological analysis. Through the multi-component hypervirial theorem, various regional theorems are derived which are then used to quantify the mechanical properties of atoms in molecules; these include the force, virial, torque, power, continuity and current theorems. In order to demonstrate the capability of the formalism, isotopically asymmetric hydrogen molecules, HD, HT and DT as well as YX systems (Y = 6Li, 7Li; X = H, D, T) composed of electrons and two different nuclei, all treated equally as quantum waves instead of clamped particles, are analyzed within context of the MC-QTAIM. The resulting computational analysis demonstrates that the MC-QTAIM is able to yield reasonable topological structures similar to those observed previously for diatomic species within context of the orthodox QTAIM. The asymmetrical nature of these species, inherent in their non-Born–Oppenhiemer wavefunctions, manifests itself clearly in the MC-QTAIM analysis yielding two distinguishable atomic basins with different properties. These differences are rationalized generally by the observed electron transfer from one basin to the other. Finally, some possible future theoretical extensions are considered briefly.

DNA barcoding to analyse taxonomically complex groups in plants: the case ofThymus(Lamiaceae)

We evaluated the utility of the core barcode regions (matK and rbcL) and the plastid intergenic spacer trnH-psbA to distinguish between Thymus spp. This is a taxonomically complex group that has been investigated so far mainly using morphological approaches. Thirty-six samples representing nine different morphospecies were collected and used for molecular analysis. The three markers showed clear amplification and sequencing. However, the genetic variation and the resulting haplotype networks showed that only Thymus capitatus forms a well-defined ‘barcoding gap’ compared with the other taxa. The identification problems observed in the other Thymus spp. may be related to reduced gene flow among populations, resulting in high intraspecific and low interspecific genetic variation. This situation does not permit the definition of species-specific barcodes. A second hypothesis suggests that morphological traits used for the delimitation of Thymus spp. do not reflect real biological and molecular species boundaries. If this is the case, the taxonomy of Thymus should be revised through extensive sampling and analyses with different tools (i.e. molecular variability, morphology, geographical distribution, etc.) to define the natural units at the species level. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 171, 687–699.

Remote Sensing in Mapping Mangrove Ecosystems — An Object-Based Approach

Over the past few decades, clearing for shrimp farming has caused severe losses of mangroves in the Mekong Delta (MD) of Vietnam. Although the increasing importance of shrimp aquaculture in Vietnam has brought significant financial benefits to the local communities, the rapid and largely uncontrolled increase in aquacultural area has contributed to a considerable loss of mangrove forests and to environmental degradation. Although different approaches have been used for mangrove classification, no approach to date has addressed the challenges of the special conditions that can be found in the aquaculture-mangrove system in the Ca Mau province of the MD. This paper presents an object-based classification approach for estimating the percentage of mangroves in mixed mangrove-aquaculture farming systems to assist the government to monitor the extent of the shrimp farming area. The method comprises multi-resolution segmentation and classification of SPOT5 data using a decision tree approach as well as local knowledge from the region of interest. The results show accuracies higher than 75% for certain classes at the object level. Furthermore, we successfully detect areas with mixed aquaculture-mangrove land cover with high accuracies. Based on these results, mangrove development, especially within shrimp farming-mangrove systems, can be monitored. However, the mangrove forest cover fraction per object is affected by image segmentation and thus does not always correspond to the real farm boundaries. It remains a serious challenge, then, to accurately map mangrove forest cover within mixed systems.

Inverse obstacle problems with backscattering or generalized backscattering data in one or two directions

This paper is concerned with scattering by a smooth compact obstacle in R. The main results are that for certain classes of obstacles knowledge of the the scattering amplitude in only one or two pairs of incident and reflected directions suffices to recover the Taylor series of a boundary defining function for the obstacle at a point. Thus certain obstacles with real analytic boundaries can be determined.

Contour Extraction of Skin Tumors Using Visual Attention and GVF-Snake Model

Contour extraction of skin tumors accurately is an important task for further feature generation of their borders and sur-faces to early diagnose melanomas. An integrated approach, combining visual attention model and GVF-snake, is pro-posed in the paper to provide a general framework for locating tumor boundaries in case of noise and boundaries with large concavity. For any skin image, the visual attention model is implemented to locate the Region of Interests (ROIs) based on saliency maps. Then an algorithm called GVF-snake is utilized to iteratively drive an initial contour, deriving from the extracted ROIs, towards real boundary of skin tumors by minimizing an energy function. It is shown from ex-periments that the proposed approach exceeds in two aspects compared with other contour-deforming methods: 1) ini-tial contours generated from saliency maps are definitely located at neighboring regions of real boundaries of skin tu-mors to speed up converges of contour deformation and achieve higher accuracy; 2) the method is not sensitive to nois-es on skins and initial contours extracted.

Reading Place: Bodies and Spaces in Québécois Adolescent Literature

This paper examines two Canadian (Quebecois) novels for young adults, translated from French to English in Canada: The Road to Chlifa by Michele Marineau, and Pieces of Me by Charlotte Gingras. We examine the representation of adolescent bodies in space and movement, and how these coming of age narratives play out in relation to discourses about nationality and citizenship. This paper suggests that there are subtle differences in sensibilities in works published in French by Quebecois writers and publishers, and that there is evidence of a lingering solitude in relation to young adult literature in Canada. We argue that we need to understand and continue to explicate the complex set of cultural readings and re-readings engendered by these and other coming of age novels that cross real and imagined boundaries of federation and language; that is, we encourage educators to examine representations of adolescent protagonists in relation to the production and reception of literary works that travel within and across our borders.

Enhancing a disparity map by color segmentation

Depth perception is a crucial but greedy task for most mobile robots to navigate in their environment and avoid obstacles. Generally, it does not need to be completed at permanent full precision but can be done in a coarse-to-fine strategy. In the present paper, a novel method is proposed to enhanc e a very sparse disparity map provided by a block matching strategy for example. To that purpose, the region and edge maps of the initial image are successively analyzed. The segmentation is achieved on the sole chrominance information to produce stable and homogeneous regions, closely related to the real boundaries of the objects. A particular attention is given to remove errors due to occlusions, by making the depth and region maps cooperate. In a second stage, the luminance variations are analyzed to fill up the depth map. Finally, the edge map computed on the luminance component is used to alleviate problems due to under-segmentation. The experiments show that the initial disparity map is successfully improved without any minimization process. A comparison is made regarding the segmentation method, whether it performs directly in the spatial domain (region-growing) or it jointly uses the color and space domains (mean-shift). In addition, two luminance-chrominance color spaces are studied: L∗u∗v∗ and ρϕθ.

World History, Liberal Arts, and Global Citizenship

Abstract This article investigates how world history can help recraft the liberal arts to better serve an interconnected, cosmopolitan, and “globalized” world in the twenty-first century. It argues that world history can help students, citizens, and educators transcend real and imagined boundaries to become more empathetic and insightful “global citizens.”

X-parameters ® -based closed-form expressions for evaluating power-dependent fundamental negative and positive real impedance boundaries in oscillator design

In this study, an analytical design tool, applicable under large-signal operation, based on X-parameters closed-form expressions, to determine the large-signal boundary between the negative (energy delivered) and positive (energy absorbing) real input impedance regions of the non-linear oscillator block, is presented to be used prior to and/or during non-linear oscillator circuit design. The consistency of the approach is demonstrated since in small-signal operation; the proposed expressions for the gamma equal to unity loci converges to the classic expression, generally referred to as the input or output stability circles. At large-signal levels, while we are not claiming that this formulation provides by itself similar general stability guidance, it can provide relevant information for oscillator design. The validity and usefulness of the proposed expressions as a real-time design aid, thus either minimising or avoiding the necessity for complex and time-consuming harmonic balance simulations, is demonstrated in the study.

Teacher education lesson observation as boundary crossing

PurposeThe purpose of this paper is to test and develop a new tool for lesson observation and feedback within the context of initial teacher education. The tool was designed to align with the practitioner enquiry model of teacher learning underpinning the course, and as such it drew mentors into the mode of responding to their students’ questions.Design/methodology/approachThe research was undertaken as a Design Study. The design of the tool led to an iterative, collaborative, process‐focused approach to the development of the observation tool. Students and their mentors were encouraged to experiment with and report on their observation experience.FindingsThe observation tool altered the quality of the mentoring relationship through focusing on enquiry as its foundation. Feedback from student teachers and their mentors helped us to define the role of observation in the process of professional learning and to review the nature of the mentoring relationship which emerged.Practical implicationsSignificant professional development and learning can be triggered by crossing both real and metaphorical boundaries and as such it is essential that the tools offered to students and their mentors are supportive of divergent learning outcomes, through which each student teacher has the opportunity to transform teaching practices, not simply replicate existing ones.Originality/valueObservation and feedback in the classroom can be viewed as a “boundary” practice. This new tool can be regarded as a “boundary object” which promotes the use of questions to support the “framing and reframing” necessary for the professional learning and development of the beginning teachers.

Primary Bone Marrow Lymphoma

Bone marrow involvement by lymphoma is considered a systemic dissemination of the disease arising elsewhere, although some tumors may arise primarily in the bone marrow microenvironment. Primary bone marrow lymphoma (PBML) is a rare entity whose real boundaries and clinicobiological significance are not well defined. Criteria to diagnose PBML encompass isolated bone marrow infiltration, with no evidence of nodal or extranodal involvement, including the bone, and the exclusion of leukemia/lymphomas that are considered to primarily involve the bone marrow. Twenty-one out of 40 lymphomas retrospectively reviewed by the International Extranodal Lymphoma Study Group from 12 institutions in 7 different countries over a 25-year period fulfilled the inclusion criteria. These cases comprised 4 follicular lymphomas (FLs), 15 diffuse large B-cell lymphomas (DLBCLs), and 2 peripheral T-cell lymphomas, not otherwise specified. The FL cases showed paratrabecular infiltration, BCL2 protein and CD10 expression, and BCL2 gene rearrangement. DLBCL showed nodular infiltration in 6 cases and was diffuse in 9 cases; it also showed positivity for BCL2 protein (9/10) and IRF4 (6/8). Median age was 65 years with male predominance. All but 3 FL patients were symptomatic. Most cases presented with cytopenias and high lactate dehydrogenase. Four patients (3 FL cases and 1 DLBCL case) had leukemic involvement. Most DLBCL patients received CHOP-like or R-CHOP-like regimens. The outcome was unfavorable, with a median overall survival of 1.8 years. In conclusion, PBML is a very uncommon lymphoma with particular clinical features and heterogenous histology. Its recognition is important to establish accurate diagnosis and adequate therapy.

S-функції у зворотніх задачах диференційної геометрії та керуванні утворення форм

Sufficiently complete system of S-functions is offers, it’s allows for the first time in world science practice to describe the real physical boundaries and the surface area of any given shape in the asymptotic approximation to any desired accuracy grade with continuously differentiable functions of ω

World History, Liberal Arts, and Global Citizenship

This article investigates how world history can help recraft the liberal arts to better serve an interconnected, cosmopolitan, and globalized world in the twenty-first century. It argues that world history can help students, citizens, and educators transcend real and imagined boundaries to become more empathetic and insightful global citizens.

Ambiguity of optical coherence tomography measurements due to rough surface scattering

Optical coherence tomography (OCT) images are frequently interpreted in terms of layers (for example, of tissue) with the boundary defined by a change in refractive index. Real boundaries are rough compared with the wavelength of light, and in this paper we show that this roughness has to be taken into account in interpreting the images. We give an example of the same OCT image obtained from two quite different objects, one smooth compared to the optical wavelength, and the other rough.

Virtual boundary element method for multistage depressed collector of traveling-wave tubes

In this study, virtual boundary element (VBE) method has been employed in multistage depressed collector (MDC) simulation for high efficiency traveling-wave tubes (TWTs). The basic idea of this method is establishing a mapping relation between the source on the real and virtual boundaries. When calculating the potential of the problem field, the virtual source on virtual boundary is only used, instead of the source on real boundary. We discussed the distance between the virtual and real boundaries and the discrete density of virtual boundary, which are closely related to the calculation accuracy. Based on the VBE method, a new computer aided design code CCAD is developed for the MDC system of high efficiency TWT. The results of simulations performed on an axisymmetric four-stage depressed collector are reported. The advantages of VBE method mainly lie in fast calculation and accurate solution. This is of benefit to designing high efficiency MDC thus developing high efficiency TWT, especially for space TWT.

Iris segmentation for non-cooperative recognition systems

Segmenting iris texture from an input image is an important step for recognising iris pattern. It is still a difficult task to localise available texture regions from non-ideal iris images captured in non-cooperative situations such as lighting variations, on-the-move and off-angle view. To address this problem, this study presents a novel algorithm for accurate and fast iris segmentation. An adaptive mean shift procedure is built to find the rough position of the iris centre. According to the localisation result, a circle is set as the initial iris contour. After combining the statistical texture prior modelled as Markov random field, a merged active contour model is established in terms of level set theory. Under the MAC model, the initial contour is iteratively driven to real iris boundaries. During the curve evolving process, eyelids, eyelashes, reflections and shadows can be simultaneously detected and labelled in iris regions. The novelty of the proposed method mainly includes developing a new modified mean shift procedure for fast and robust iris localisation, and successfully incorporating the local probabilistic prior, boundary and region information into the designed active contour model for accurate texture segmentation. Extensive experimental results on various challenging iris images show that our method can effectively and accurately perform iris segmentation with low computational complexity and has very promising applications in non-cooperative recognition systems.

Трансферы Даниэля Штайна

In this article Liudmila Ulitskaiaʼs 2007 novel Daniel Shtain, Translator is analysed in terms of changes and transfer, as transgression of real and fictive boundaries. Two types of transfer are distinguished in the novel, external, when the hero is forced to change his identity, and internal, when he changes of his own free will. Ultimately, it is argued, the hero remains essentially identical to himself.

A Novel Texture-Preceded Segmentation Algorithm for High-Resolution Imagery

Image segmentation is crucial to object-oriented remote sensing imagery analysis. In this paper, a novel texture-preceded segmentation algorithm is proposed for high-resolution remote sensing imagery, in which texture clustering is first carried out as a loose constraint for later segmentation. The algorithm is based on the graph models of region adjacency graph and nearest neighbor graph, which can achieve fast node merging, depending on the global optimum. Here, a combined distance, composed of texture, spectral, and shape features, is established to measure the similarity between nodes and gives the same semantic descriptions for the texture objects. Then, the combined distance is applied to graph models, and the final segmentation result can be obtained iteratively by fast merging. During the merging process, optimal sequence merging interacts with texture clustering to refine the real edges of a texture region. This algorithm cannot only merge the homogeneous texture segments with spectral variability easily but can also detect the real object boundaries well. The experiments on high-resolution imagery show that, in terms of the same number of segments, the proposed algorithm can improve segmentation accuracy by 10%-20% compared to the results obtained by pure spectral features with Definiens Developer software.

3D DEM/CFD analysis of size-induced segregation during die filling

The flow and segregation behaviours of the binary mixtures with different particle sizes during die filling in air and in a vacuum were investigated using a coupled discrete element method (DEM) and computational fluid dynamics (CFD) in three dimensions (3D). Two types of computational setups were considered: i) a fully 3D model with real wall boundaries and ii) a thin sliced model with a slice of the full domain using two parallel periodic boundaries. Die filling with a stationary shoe and a moving shoe were simulated. It was found that the flow and segregation results obtained using the fully 3D and thin sliced models were essentially identical, implying that the thin sliced model can be used to simulate the die filling with a reduced computational time and good accuracy. It was also observed that, for die filling with a stationary shoe, the powder flow rate was reduced by the entrapped air in the die. For the die filling in a vacuum, vertical segregation occurred with a high concentration of fine particles at the bottom of the die as the fine particles can sift through the voids between coarse particles. The presence of air reduced the extent of this segregation by suppressing the percolation of fines through the voids. For die filling with a moving shoe, the effect of air on powder flow and segregation behaviours is negligible when the process is dominated by nose flow as considered in this study, since the air can readily escape from the die cavity. Segregation was also induced during die filling with a moving shoe, due to the free surface segregation and the filtration of fines through the voids between the coarse particles. Consequently, a high overall concentration of fines in the die was obtained, while the concentration of fines at the far end of the die was much lower than that at the near end.

Spherical extension property no longer true for domains in algebraic variety with isolated singularity

Let D be a domain in ℂn. It is known that if D is a simply connected bounded domain in ℂ with spherical real analytic boundary ∂D, then every local biholomorphic map at boundary as above extends to a biholomorphic map from D onto the unit ball in ℂn. As a consequence, a local biholomorphic map between D1 and D2 where D1 and D2 are simply connected domains in ℂn with spherical real analytic boundaries can extend to a global biholomorphic map from D1 onto D2. If the boundary is algebraic, the simply connected condition in the above result can be dropped. In this note, we show that the above phenomenon is no longer true if domains are in algebraic varieties with isolated singularities.