Convergence of mayer expansions
International Nuclear Information System (INIS)
Brydges, D.C.
1986-01-01
The tree graph bound of Battle and Federbush is extended and used to provide a simple criterion for the convergence of (iterated) Mayer expansions. As an application estimates on the radius of convergence of the Mayer expansion for the two-dimensional Yukawa gas (nonstable interaction) are obtained
Convergence of hyperspherical adiabatic expansion for helium-like systems
International Nuclear Information System (INIS)
Abrashkevich, A.G.; Abrashkevich, D.G.; Pojda, V.Yu.; Vinitskij, S.I.; Kaschiev, M.S.; Puzynin, I.V.
1988-01-01
The convergence of hyperspherical adiabatic expansion has been studied numerically. The spectral problems arising after separation of variables are solved by the finite-difference and finite element methods. The energies of the ground and some doubly excited staes of a hydrogen ion are calculated in the six-channel approximation within the 10 -4 a.u. accuracy. Obtained results demonstrate a rapid convergence of the hyperspherical adiabatic expansion. 14 refs.; 5 tabs
Convergence of the multiple scattering expansion in XAFS and XANES
International Nuclear Information System (INIS)
Rehr, J.J.
1992-01-01
The convergence of the multiple-scattering expansion of XAFS and XANES by explicit path-bypath calculations. The approach is based on the fast scattering matrix formalism of Rehr and Albers, together with an automated path finder and filters that exclude negligible paths. High-order scattering terms are found to be essential, especially at low energies. Several factors including the magnitude of curved wave scattering amplitudes, inelastic losses and multiple-scattering Debye-Waller factors control convergence of the expansion. The convergence is illustrated explicitly for the case of diatomic molecules
A convergence theorem for asymptotic expansions of Feynman amplitudes
International Nuclear Information System (INIS)
Mabouisson, A.P.C.
1999-06-01
The Mellin representations of Feynman integrals is revisited. From this representation, and asymptotic expansion for generic Feynman amplitudes, for any set of invariants going to zero or to ∞, may be obtained. In the case of all masses going to zero in Euclidean metric, we show that the truncated expansion has a rest compatible with convergence of the series. (author)
On the Convergence of the Virial Expansion
Ramawadh, S.D.
2015-01-01
The virial expansion appears in statistical mechanics, an area where physics and mathematics intersect. Throughout this thesis we will mostly ignore the physics and mainly focus on the mathematical aspects. This is a deliberate choice, made for two reasons. Firstly, there are several books that
Ground state energies from converging and diverging power series expansions
International Nuclear Information System (INIS)
Lisowski, C.; Norris, S.; Pelphrey, R.; Stefanovich, E.; Su, Q.; Grobe, R.
2016-01-01
It is often assumed that bound states of quantum mechanical systems are intrinsically non-perturbative in nature and therefore any power series expansion methods should be inapplicable to predict the energies for attractive potentials. However, if the spatial domain of the Schrödinger Hamiltonian for attractive one-dimensional potentials is confined to a finite length L, the usual Rayleigh–Schrödinger perturbation theory can converge rapidly and is perfectly accurate in the weak-binding region where the ground state’s spatial extension is comparable to L. Once the binding strength is so strong that the ground state’s extension is less than L, the power expansion becomes divergent, consistent with the expectation that bound states are non-perturbative. However, we propose a new truncated Borel-like summation technique that can recover the bound state energy from the diverging sum. We also show that perturbation theory becomes divergent in the vicinity of an avoided-level crossing. Here the same numerical summation technique can be applied to reproduce the energies from the diverging perturbative sums.
Ground state energies from converging and diverging power series expansions
Energy Technology Data Exchange (ETDEWEB)
Lisowski, C.; Norris, S.; Pelphrey, R.; Stefanovich, E., E-mail: eugene-stefanovich@usa.net; Su, Q.; Grobe, R.
2016-10-15
It is often assumed that bound states of quantum mechanical systems are intrinsically non-perturbative in nature and therefore any power series expansion methods should be inapplicable to predict the energies for attractive potentials. However, if the spatial domain of the Schrödinger Hamiltonian for attractive one-dimensional potentials is confined to a finite length L, the usual Rayleigh–Schrödinger perturbation theory can converge rapidly and is perfectly accurate in the weak-binding region where the ground state’s spatial extension is comparable to L. Once the binding strength is so strong that the ground state’s extension is less than L, the power expansion becomes divergent, consistent with the expectation that bound states are non-perturbative. However, we propose a new truncated Borel-like summation technique that can recover the bound state energy from the diverging sum. We also show that perturbation theory becomes divergent in the vicinity of an avoided-level crossing. Here the same numerical summation technique can be applied to reproduce the energies from the diverging perturbative sums.
Convergent perturbation expansions for Euclidean quantum field theory
International Nuclear Information System (INIS)
Mack, G.; Pordt, A.
1984-09-01
Mayer perturbation theory is designed to provide computable convergent expansions which permit calculation of Greens functions in Euclidean Quantum Field Theory to arbitrary accuracy, including 'nonperturbative' contributions from large field fluctuations. Here we describe the expansions at the example of 3-dimensional lambdaphi 4 -theory (in continuous space). They are not essentially more complicated than standard perturbation theory. The n-th order term is expressed in terms of 0(n)-dimensional integrals, and is of order lambda 4 if 4k-3<=n<=4k. (orig.)
On the convergence of quantum resonant-state expansion
International Nuclear Information System (INIS)
Brown, J. M.; Bahl, A.; Jakobsen, P.; Moloney, J. V.; Kolesik, M.
2016-01-01
Completeness of the system of Stark resonant states is investigated for a one-dimensional quantum particle with the Dirac-delta potential exposed to an external homogeneous field. It is shown that the resonant series representation of a given wavefunction converges on the negative real axis while the series diverges on the positive axis. Despite the divergent nature of the resonant expansion, good approximations can be obtained in a compact spatial domain.
On the convergence of quantum resonant-state expansion
Energy Technology Data Exchange (ETDEWEB)
Brown, J. M.; Bahl, A. [College of Optical Sciences, University of Arizona, 1630 East University Boulevard, Tucson, Arizona 85721 (United States); Jakobsen, P. [Department of Mathematics and Statistics, University of Tromsø, Tromsø (Norway); Moloney, J. V.; Kolesik, M. [College of Optical Sciences, University of Arizona, 1630 East University Boulevard, Tucson, Arizona 85721 (United States); Arizona Center for Mathematical Sciences, University of Arizona, Tucson, Arizona 85721 (United States)
2016-03-15
Completeness of the system of Stark resonant states is investigated for a one-dimensional quantum particle with the Dirac-delta potential exposed to an external homogeneous field. It is shown that the resonant series representation of a given wavefunction converges on the negative real axis while the series diverges on the positive axis. Despite the divergent nature of the resonant expansion, good approximations can be obtained in a compact spatial domain.
Convergence of high-intensity expansions for atomic ionization
International Nuclear Information System (INIS)
Antunes Neto, H.S.; Davidovich, L.
1984-01-01
It is shown that a frequently used nonperturbative approximation for atomic ionization rates is cancelled out when corrections are taken into account. This explains the strong gauge dependence of previous results. A convergent and gauge invariant expansion is obtained. Numerical results show that its first term, which may be calculated analytically in many cases, describes very well the time-dependent behaviour of the ionization probability, for very strong fields. (Author) [pt
Surgically assisted rapid maxillary expansion in adults.
Pogrel, M A; Kaban, L B; Vargervik, K; Baumrind, S
1992-01-01
Twelve adults with maxillary width discrepancy of greater than 5 mm were treated by surgically assisted rapid maxillary expansion. The procedure consisted of bilateral zygomatic buttress and midpalatal osteotomies combined with the use of a tooth-borne orthopedic device postoperatively. Mean palatal expansion of 7.5 mm (range of 6 to 13 mm), measured in the first molar region, was achieved within 3 weeks in all patients. Expansion remained stable during the 12-month study period, with a mean relapse for the entire group of 0.88 +/- 0.48 mm. Morbidity was limited to mild postoperative discomfort. The results of this preliminary study indicated that surgically assisted rapid maxillary expansion is a safe, simple, and reliable procedure for achieving a permanent increase in skeletal maxillary width in adults. Further study is necessary to document the three-dimensional movements of the maxillary segments and long-term stability of the skeletal and dental changes.
The Convergence Problems of Eigenfunction Expansions of Elliptic Differential Operators
Ahmedov, Anvarjon
2018-03-01
In the present research we investigate the problems concerning the almost everywhere convergence of multiple Fourier series summed over the elliptic levels in the classes of Liouville. The sufficient conditions for the almost everywhere convergence problems, which are most difficult problems in Harmonic analysis, are obtained. The methods of approximation by multiple Fourier series summed over elliptic curves are applied to obtain suitable estimations for the maximal operator of the spectral decompositions. Obtaining of such estimations involves very complicated calculations which depends on the functional structure of the classes of functions. The main idea on the proving the almost everywhere convergence of the eigenfunction expansions in the interpolation spaces is estimation of the maximal operator of the partial sums in the boundary classes and application of the interpolation Theorem of the family of linear operators. In the present work the maximal operator of the elliptic partial sums are estimated in the interpolation classes of Liouville and the almost everywhere convergence of the multiple Fourier series by elliptic summation methods are established. The considering multiple Fourier series as an eigenfunction expansions of the differential operators helps to translate the functional properties (for example smoothness) of the Liouville classes into Fourier coefficients of the functions which being expanded into such expansions. The sufficient conditions for convergence of the multiple Fourier series of functions from Liouville classes are obtained in terms of the smoothness and dimensions. Such results are highly effective in solving the boundary problems with periodic boundary conditions occurring in the spectral theory of differential operators. The investigations of multiple Fourier series in modern methods of harmonic analysis incorporates the wide use of methods from functional analysis, mathematical physics, modern operator theory and spectral
Rapidly converging path integral formalism. Pt. 1
International Nuclear Information System (INIS)
Bender, I.; Gromes, D.; Marquard, U.
1990-01-01
The action to be used in the path integral formalism is expanded in a systematic way in powers of the time spacing ε in order to optimize the convergence to the continuum limit. This modifies and extends the usual formalism in a transparent way. The path integral approximation to the Green function obtained by this method approaches the continuum Green function with a higher power of ε than the usual one. The general theoretical derivations are exemplified analytically for the harmonic oscillator and by Monte Carlo methods for the anharmonic oscillator. We also show how curvilinear coordinates and curved spaces can naturally be treated within this formalism. Work on field theory is in progress. (orig.)
Rapid maxillary expansion in contemporary orthodontic literature
Directory of Open Access Journals (Sweden)
Sabrina Mutinelli
2016-01-01
Full Text Available We have reviewed our retrospective research about rapid maxillary expansion performed in the early mixed dentition to summarize the results of different studies regarding maxillary dental arch width variation and crowding improvement in light of contemporary literature. The aim is to define the effects of treatments followed until the end of dental arch growth. In all studies, a Haas expander anchored to the deciduous dentition was used. The samples consisted of treated patients with and without a lateral crossbite and homogeneous untreated individuals as controls. Two additional control groups of adolescents and adults in dental Class 1 were also compared. As a result of the analysis, rapid maxillary expansion with anchorage to the deciduous dentition was found to be effective in increasing transverse width in intermolar and intercanine areas, and the change was preserved until the full permanent dentition stage. When performed before maxillary lateral incisors have fully erupted, this procedure allows for a rapid increase in the arch length in the anterior area and consequently, in the space available for permanent incisors with a stable reduction in crowding over time.
Toward convergence of the variational mass expansion in asymptotically free theories
Kneur, J L
2001-01-01
We re-examine a modification of perturbative expansions, valid for asymptotically free theories, producing "variationally improved" expansions of physical quantities relevant to dynamical (chiral) symmetry breaking. The large order behaviour of this expansion is shown to be drastically improved, for reasons analogous to the convergence properties of the delta-expansion of the anharmonic oscillator.
A rapid and convergent synthesis of the integrastatin core
Tadross, Pamela M.; Bugga, Pradeep; Stoltz, Brian M.
2011-01-01
The tetracyclic core of the integrastatin natural products has been prepared in a convergent and rapid manner. Our strategy relies upon a palladium(ii)-catalyzed oxidative cyclization to form the central [3.3.1]-dioxabicycle of the natural product core. Overall, the core has been completed in only 4 linear steps from known compounds. © 2011 The Royal Society of Chemistry.
Topological charges and convergence of the cluster expansion
International Nuclear Information System (INIS)
Simonov, Yu.A.
1989-01-01
Cluster expansion of Wilson loops is shown to diverge for the QCD vacuum populated by topological objects (instantons, magnetic monopoles). Using simple models the total sum of the cluster expansion for the string tension is calculated and found to be zero for instantons and nonzero for magnetic monopoles. 14 refs
Convergence of perturbation theory expansion for the Yukawa interaction
International Nuclear Information System (INIS)
Basuev, A.G.
1975-01-01
It is shown that the perturbation theory series in the translational-invariant case and upon removal of the boson propagator cut-off for euclidian Green's functions converges when gsup(2)/2 2 is the mass of the boson and Δ(o) is the fermion propagator in the zero of kappa-space. This problem was previously considered by other methods in respect of pseudo-euclidian functions (for the S-matrix) and of euclidian Green's functions. (author)
World NGL markets continue rapid expansion
International Nuclear Information System (INIS)
Otto, K.; Gist, R.; Whitley, C.; Haun, R.
1998-01-01
The international LPG industry has expanded rapidly during the 1990s and undergone significant changes. LPG consumption has expanded at nearly twice the rate of world petroleum demand. In particular, LPG use in residential and commercial markets has more than doubled in many developing countries. Markets for LPG and other petroleum products have been opened in many countries, accelerating demand growth and creating investment opportunities in all downstream segments. This has led to an overall strengthening of global LPG pricing and the development of many new export gas-processing projects. The paper discusses world LPG demand in residential and commercial markets and in petrochemicals, world LPG supply, regional increases, international trade, the US situation in natural gas, NGL supply, and NGL demand
Fragmentation of Ceramics in Rapid Expansion Mode
Maiti, Spandan; Geubelle, Philippe H.; Rangaswamy, Krishnan
The study of the fragmentation process goes back to more than a century, motivated primarily by problems related to mining and ore handling (Grady and Kipp, 1985). Various theories have been proposed to predict the fragmentation stress and the fragment size and distribution. But the investigations are generally case specific and relate to only a narrow set of fragmentation processes. A number of theoretical studies of dynamic fragmentation in a rapidly expanding body can be found in the literature. For example, the study summarized in (Grady, 1982) presents a model based on a simple energy balance concept between the surface energy released due to fracture and the kinetic energy of the fragments. Subsequent refinements of the energy balance model have been proposed by (Glenn and Chudnovsky, 1986), which take into account the strain energy of the fragments and specify a threshold stress below which no fragmentation occurs. These models assume that the fracture events are instantaneous and occur simultaneously. Evidently, these assumptions are quite restrictive and these models can not take into account the transient nature of the fragmentation process after the onset of fracture in the material. A more recent model proposed by (Miller et al., 1999) however takes into account this time-dependent nature of the fragmentation event and the distribution of flaws of various strengths in the original material.
The convergence radius of the chiral expansion in the Dyson-Schwinger approach
International Nuclear Information System (INIS)
Meissner, T.
1994-01-01
We determine the convergence radius m conv or the expansion in the current quark mass using the Dyson-Schwinger (DS) equation of QCD in the rainbow approximation. Within a Gaussian form for the gluon propagator D μ ν(p) ∼ δμνχ 2 e - Δ /p 2 we find that m conv increases with decreasing width Δ and increasing strength χ 2 . For those values of χ 2 and Δ, which provide the best known description of low energy hadronic phenomena, m conv lies around 2Λ QCD , which is big enough, that the chiral expansion in the strange sector converges. Our analysis also explains the rather low value of m conv ∼ 50...80 MeV in the Nambu-Jona-Lasinio model, which as itself can be regarded as a special case of the rainbow DS models, where the gluon propagator is a constant in momentum space
Surgically Assisted Rapid Maxillary Expansion: surgical and orthodontic aspects
M.J. Koudstaal (Maarten)
2008-01-01
textabstractThe scope of this thesis is to shed more light, from a number of perspectives, on surgically assisted rapid maxillary expansion (SARME). The primary questions this thesis set out to answer were; ‘is there a difference in stability between bone-borne and tooth-borne distraction?’ and ‘can
Rapid Convergence and Subduction at the Intersections of Fronts
D'Asaro, E. A.
2016-12-01
An array of 300 surface drifters drogued to follow the top 0.6m of the ocean were deployed in the northern Gulf of Mexico near the Deep Water Horizon spill site in January of 2016. As expected, the array spread from its initial 15x15km scale with the second moment increasing at a rate roughly consistent with historical dispersion curves. More surprisingly, a large fraction of the drifters accumulated within a km-scale submesoscale eddy and grouped into clusters often only a few meters apart. This occurred due to surface convergence, as opposed to purely confluence, with convergence rates of many f feeding downward-going subduction zones with vertical velocities of a few centimeters per second. These convergences preferentially occurred at density fronts and in particular at junctions of density fronts on the periphery of submesoscale eddies. These observations complement the traditional view of lateral dispersion of surface particles by mesoscale eddies with a competing submesocale convergence and provide direct observations of the strong vertical exchanges associated with submesoscale eddies and fronts.
Reformulation of nonlinear integral magnetostatic equations for rapid iterative convergence
International Nuclear Information System (INIS)
Bloomberg, D.S.; Castelli, V.
1985-01-01
The integral equations of magnetostatics, conventionally given in terms of the field variables M and H, are reformulated with M and B. Stability criteria and convergence rates of the eigenvectors of the linear iteration matrices are evaluated. The relaxation factor β in the MH approach varies inversely with permeability μ, and nonlinear problems with high permeability converge slowly. In contrast, MB iteration is stable for β 3 , the number of iterations is reduced by two orders of magnitude over the conventional method, and at higher permeabilities the reduction is proportionally greater. The dependence of MB convergence rate on β, degree of saturation, element aspect ratio, and problem size is found numerically. An analytical result for the MB convergence rate for small nonlinear problems is found to be accurate for βless than or equal to1.2. The results are generally valid for two- and three-dimensional integral methods and are independent of the particular discretization procedures used to compute the field matrix
International Nuclear Information System (INIS)
Honkonen, J.; Komarova, M.; Nalimov, M.
2002-01-01
Large order asymptotic behaviour of renormalization constants in the minimal subtraction scheme for the φ 4 (4 - ε) theory is discussed. Well-known results of the asymptotic 4 - ε expansion of critical indices are shown to be far from the large order asymptotic value. A convergent series for the model φ 4 (4 - ε) is then considered. Radius of convergence of the series for Green functions and for renormalisation group functions is studied. The results of the convergent expansion of critical indices in the 4 - ε scheme are revalued using the knowledge of large order asymptotics. Specific features of this procedure are discussed (Authors)
eRME - Rapid Maxillary Expansion in the economic way
Directory of Open Access Journals (Sweden)
Sonali Mahadevia
2011-01-01
Full Text Available Aim and Objectives: Rapid Maxillary Expansion constitutes a routine clinical procedure in orthodontics, involving separation of mid-palatine suture which is usually done with help of the Hyrax screw. However, because of its high cost, the use has been limited, especially in institutions. So, the purpose of this study was to construct an economical device which can expand the maxillary arch in growing patients. Materials and Methods: Six patients having constricted maxilla and posterior skeletal crossbite were randomly selected from the Department of Orthodontics. A unique, easy and simple alternative device for expanding the maxillary arch called economic Rapid Maxillary Expander (eRME has been fabricated at about one-tenth the cost of the conventional Hyrax. Pre- and post-treatment effects were statistically tested by using paired t-test at 0.05 level of significance. Results and Conclusion: The study results showed an average expansion in canine, premolar and molar regions of 4.4 mm, 6.8 mm and 9.4 mm, respectively, having significant difference pre-and post-treatment. Thus, it shows that maxillary expansion is efficiently possible with the application of this newly constructed device named eRME. This appliance also acts as a fixed retainer to avoid relapse, hence negating the need for a separate retainer.
The thermospheric effects of a rapid polar cap expansion
Directory of Open Access Journals (Sweden)
D. W. Idenden
Full Text Available In a previous publication we used results from a coupled thermosphere-ionosphere-plasmasphere model to illustrate a new mechanism for the formation of a large-scale patch of ionisation arising from a rapid polar cap expansion. Here we describe the thermospheric response to that polar cap expansion, and to the ionospheric structure produced. The response is dominated by the energy and momentum input at the dayside throat during the expansion phase itself. These inputs give rise to a large-scale travelling atmospheric disturbance (TAD that propagates both antisunward across the polar cap and equatorward at speeds much greater than both the ion drifts and the neutral winds. We concentrate only on the initially poleward travelling disturbance. The disturbance is manifested in the neutral temperature and wind fields, the height of the pressure level surfaces and in the neutral density at fixed heights. The thermospheric effects caused by the ionospheric structure produced during the expansion are hard to discern due to the dominating effects of the TAD.
Key words. Ionosphere (ionosphere · atmosphere interaction; modeling and forecasting; plasma convection.
Alveolar bone changes after asymmetric rapid maxillary expansion.
Akin, Mehmet; Baka, Zeliha Muge; Ileri, Zehra; Basciftci, Faruk Ayhan
2015-09-01
To quantitatively evaluate the effects of asymmetric rapid maxillary expansion (ARME) on cortical bone thickness and buccal alveolar bone height (BABH), and to determine the formation of dehiscence and fenestration in the alveolar bone surrounding the posterior teeth, using cone-beam computed tomography (CBCT). The CBCT records of 23 patients with true unilateral posterior skeletal crossbite (10 boys, 14.06 ± 1.08 years old, and 13 girls, 13.64 ± 1.32 years old) who had undergone ARME were selected from our clinic archives. The bonded acrylic ARME appliance, including an occlusal stopper, was used on all patients. CBCT records had been taken before ARME (T1) and after the 3-month retention period (T2). Axial slices of the CBCT images at 3 vertical levels were used to evaluate the buccal and palatal aspects of the canines, first and second premolars, and first molars. Paired samples and independent sample t-tests were used for statistical comparison. The results suggest that buccal cortical bone thickness of the affected side was significantly more affected by the expansion than was the unaffected side (P ARME significantly reduced the BABH of the canines (P ARME also increased the incidence of dehiscence and fenestration on the affected side. ARME may quantitatively decrease buccal cortical bone thickness and height on the affected side.
[Piezosurgery for surgically assisted rapid maxillary expansion under local anesthesia].
Sun, Hao; Li, Biao; Sun, Hao; Liu, Zhixu; Wang, Xudong
2014-08-01
This study evaluates piezosurgery for surgically assisted rapid maxillary expansion (SARME) under local anesthesia. SARME was performed on adults with maxillary transverse deficiency under local anesthesia with a piezosurgical device. Fourteen patients (six males and eight females) underwent lateral maxillary osteotomies, midpalatal osteotomies, and bilateral pterygomaxillary disjunction. The feelings of patients during the operation were determined through questionnaires. All patients underwent SARME in the out-patient operating room. The surgical procedures were completed under local anesthesia. All patients exhibited satisfactory tolerance. Ultrasonic bone-cutting surgery was recently introduced as a feasible alternative to the conventional tools of cranio-maxillofacial surgery for its technical characteristics of precision and safety. The device used was unique in that cutting action occurred when the tool was employed on mineralized tissues, but stoped on soft tissues. The results of the questionnaires showed that eight (57.14%) patients felt a mild sensation of ultrasonic vibration, tweleve (85.7 1%) felt mild tolerable pain and tooth soreness during surgery, and eleven (78.57%) felt little fear and hardly heard the ultrasonic sound. Preoperative and postoperative six months later measurements showed an evident effect of expansion. Piezosurgery enabled patients to undergo all the steps of SARME under local anesthesia, but more cases and longer follow-up are needed to verif ' the results.
Darcie, Thomas E.; Doverspike, Robert; Zirngibl, Martin; Korotky, Steven K.
2005-09-01
Call for Papers: Convergence The Journal of Optical Networking (JON) invites submissions to a special issue on Convergence. Convergence has become a popular theme in telecommunications, one that has broad implications across all segments of the industry. Continual evolution of technology and applications continues to erase lines between traditionally separate lines of business, with dramatic consequences for vendors, service providers, and consumers. Spectacular advances in all layers of optical networking-leading to abundant, dynamic, cost-effective, and reliable wide-area and local-area connections-have been essential drivers of this evolution. As services and networks continue to evolve towards some notion of convergence, the continued role of optical networks must be explored. One vision of convergence renders all information in a common packet (especially IP) format. This vision is driven by the proliferation of data services. For example, time-division multiplexed (TDM) voice becomes VoIP. Analog cable-television signals become MPEG bits streamed to digital set-top boxes. T1 or OC-N private lines migrate to Ethernet virtual private networks (VPNs). All these packets coexist peacefully within a single packet-routing methodology built on an optical transport layer that combines the flexibility and cost of data networks with telecom-grade reliability. While this vision is appealing in its simplicity and shared widely, specifics of implementation raise many challenges and differences of opinion. For example, many seek to expand the role of Ethernet in these transport networks, while massive efforts are underway to make traditional TDM networks more data friendly within an evolved but backward-compatible SDH/SONET (synchronous digital hierarchy and synchronous optical network) multiplexing hierarchy. From this common underlying theme follow many specific instantiations. Examples include the convergence at the physical, logical, and operational levels of voice and
International Nuclear Information System (INIS)
Jankowski, K.; Malinowski, P.; Polasik, M.
1977-01-01
The convergence patterns of the l expansion of the wavefunction for the excited 2 1 S and 3 1 S states of the helium atom are studied by means of the variational method. Particular attention is devoted to the radial energy limits. (author)
DEFF Research Database (Denmark)
Madsen, Ole Brun; Nielsen, Jens Frederik Dalsgaard; Schiøler, Henrik
2002-01-01
Convergence trends between the WAN Internet area, characterized by best effort service provision, and the real time LAN domain, with requirements for guaranteed services, are identified and discussed. A bilateral evolution is identified, where typical bulk service applications from WAN, such as m......Convergence trends between the WAN Internet area, characterized by best effort service provision, and the real time LAN domain, with requirements for guaranteed services, are identified and discussed. A bilateral evolution is identified, where typical bulk service applications from WAN...... with the emergence of remote service provision, such as supervision and control of decentralized heating facilities and wind based electrical power production. The reliability issue is addressed from a structural viewpoint, where the concept of Structural QoS (SQoS) is defined to support reliability modelling...
DEFF Research Database (Denmark)
Prasad, Ramjee
2009-01-01
This paper presents the main conclusions which can be drawn from the discussions on Future Communication Systems and lessons on Unpredictable Future of Wireless Communication Systems. Future systems beyond the third generation are already under discussions in international bodies, such as ITU, WW...... and R&D programmes worldwide. The incoming era is characterized by the convergence of networks and access technology and the divergence of applications. Future mobile communication systems should bring something more than only faster data or wireless internet access....
Darcie, Thomas E.; Doverspike, Robert; Zirngibl, Martin; Korotky, Steven K.
2005-01-01
.p {padding-bottom:6px} Call for Papers: Convergence Guest Editors: Thomas E. Darcie, University of Victoria Robert Doverspike, AT&T Martin Zirngibl, Lucent Technologies Coordinating Associate Editor: Steven K. Korotky, Lucent Technologies The Journal of Optical Networking (JON) invites submissions to a special issue on Convergence. Convergence has become a popular theme in telecommunications, one that has broad implications across all segments of the industry. Continual evolution of technology and applications continues to erase lines between traditionally separate lines of business, with dramatic consequences for vendors, service providers, and consumers. Spectacular advances in all layers of optical networking-leading to abundant, dynamic, cost-effective, and reliable wide-area and local-area connections-have been essential drivers of this evolution. As services and networks continue to evolve towards some notion of convergence, the continued role of optical networks must be explored. One vision of convergence renders all information in a common packet (especially IP) format. This vision is driven by the proliferation of data services. For example, time-division multiplexed (TDM) voice becomes VoIP. Analog cable-television signals become MPEG bits streamed to digital set-top boxes. T1 or OC-N private lines migrate to Ethernet virtual private networks (VPNs). All these packets coexist peacefully within a single packet-routing methodology built on an optical transport layer that combines the flexibility and cost of data networks with telecom-grade reliability. While this vision is appealing in its simplicity and shared widely, specifics of implementation raise many challenges and differences of opinion. For example, many seek to expand the role of Ethernet in these transport networks, while massive efforts are underway to make traditional TDM networks more data friendly within an evolved but backward-compatible SDH/SONET (synchronous digital hierarchy and
Rapid replacement of bridge deck expansion joints study - phase I.
2014-12-01
Bridge deck expansion joints are used to allow for movement of the bridge deck due to thermal expansion, dynamics loading, and : other factors. More recently, expansion joints have also been utilized to prevent the passage of winter de-icing chemical...
Ahmedov, Anvarjon; Materneh, Ehab; Zainuddin, Hishamuddin
2017-09-01
The relevance of waves in quantum mechanics naturally implies that the decomposition of arbitrary wave packets in terms of monochromatic waves plays an important role in applications of the theory. When eigenfunction expansions does not converge, then the expansions of the functions with certain smoothness should be considered. Such functions gained prominence primarily through their application in quantum mechanics. In this work we study the almost everywhere convergence of the eigenfunction expansions from Liouville classes L_p^α ({T^N}), related to the self-adjoint extension of the Laplace operator in torus TN . The sufficient conditions for summability is obtained using the modified Poisson formula. Isomorphism properties of the elliptic differential operators is applied in order to obtain estimation for the Fourier series of the functions from the classes of Liouville L_p^α .
Suratwala, Tayyab; Steele, Rusty; Feit, Michael; Dylla-Spears, Rebecca; Desjardin, Richard; Mason, Dan; Wong, Lana; Geraghty, Paul; Miller, Phil; Shen, Nan
2014-01-01
Convergent Polishing is a novel polishing system and method for finishing flat and spherical glass optics in which a workpiece, independent of its initial shape (i.e., surface figure), will converge to final surface figure with excellent surface quality under a fixed, unchanging set of polishing parameters in a single polishing iteration. In contrast, conventional full aperture polishing methods require multiple, often long, iterative cycles involving polishing, metrology and process changes to achieve the desired surface figure. The Convergent Polishing process is based on the concept of workpiece-lap height mismatch resulting in pressure differential that decreases with removal and results in the workpiece converging to the shape of the lap. The successful implementation of the Convergent Polishing process is a result of the combination of a number of technologies to remove all sources of non-uniform spatial material removal (except for workpiece-lap mismatch) for surface figure convergence and to reduce the number of rogue particles in the system for low scratch densities and low roughness. The Convergent Polishing process has been demonstrated for the fabrication of both flats and spheres of various shapes, sizes, and aspect ratios on various glass materials. The practical impact is that high quality optical components can be fabricated more rapidly, more repeatedly, with less metrology, and with less labor, resulting in lower unit costs. In this study, the Convergent Polishing protocol is specifically described for fabricating 26.5 cm square fused silica flats from a fine ground surface to a polished ~λ/2 surface figure after polishing 4 hr per surface on a 81 cm diameter polisher. PMID:25489745
Face and Convergent Validity of Persian Version of Rapid Office Strain Assessment (ROSA Checklist
Directory of Open Access Journals (Sweden)
Afrouz Armal
2016-01-01
Full Text Available Objective: The aim of this work was the translation, cultural adaptation and validation of the Persian version of the Rapid Office Stress Assessment (ROSA checklist. Material & Methods: This methodological study was conducted according of IQOLA method. 100 office worker were selected in order to carry out a psychometric evaluation of the ROSA checklist by performing validity (face and convergent analyses. The convergent validity was evaluated using RULA checklist. Results: Upon major changes made to the ROSA checklist during the translation/cultural adaptation process, face validity of the Persian version was obtained. Spearman correlation coefficient between total score of ROSA check list and RULA checklist was significant (r=0.76, p<0.0001. Conclusion: The results indicated that the translated version of the ROSA checklist is acceptable in terms of face validity, convergent validity in target society, and hence provides a useful instrument for assessing Iranian office workers
Hamedi-Sangsari, Adrien; Chinipardaz, Zahra; Carrasco, Lee
2017-10-01
The aim of this study was to compare outcome measurements of skeletal and dental expansion with bone-borne (BB) versus tooth-borne (TB) appliances after surgically assisted rapid palatal expansion (SARPE). This study was performed to provide quantitative measurements that will help the oral surgeon and orthodontist in selecting the appliance with, on average, the greatest amount of skeletal expansion and the least amount of dental expansion. A computerized database search was performed using PubMed, EBSCO, Cochrane, Scopus, Web of Science, and Google Scholar on publications in reputable oral surgery and orthodontic journals. A systematic review and meta-analysis was completed with the predictor variable of expansion appliance (TB vs BB) and outcome measurement of expansion (in millimeters). Of 487 articles retrieved from the 6 databases, 5 articles were included, 4 with cone-beam computed tomographic (CBCT) data and 1 with non-CBCT 3-dimensional cast data. There was a significant difference in skeletal expansion (standardized mean difference [SMD], 0.92; 95% confidence interval [CI], 0.54-1.30; P appliances. However, there was no significant difference in dental expansion (SMD, 0.05; 95% CI, -0.24 to 0.34; P = .03). According to the literature, to achieve more effective skeletal expansion and minimize dental expansion after SARPE, a BB appliance should be favored. Copyright © 2017 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.
A Rapid Convergent Low Complexity Interference Alignment Algorithm for Wireless Sensor Networks
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Lihui Jiang
2015-07-01
Full Text Available Interference alignment (IA is a novel technique that can effectively eliminate the interference and approach the sum capacity of wireless sensor networks (WSNs when the signal-to-noise ratio (SNR is high, by casting the desired signal and interference into different signal subspaces. The traditional alternating minimization interference leakage (AMIL algorithm for IA shows good performance in high SNR regimes, however, the complexity of the AMIL algorithm increases dramatically as the number of users and antennas increases, posing limits to its applications in the practical systems. In this paper, a novel IA algorithm, called directional quartic optimal (DQO algorithm, is proposed to minimize the interference leakage with rapid convergence and low complexity. The properties of the AMIL algorithm are investigated, and it is discovered that the difference between the two consecutive iteration results of the AMIL algorithm will approximately point to the convergence solution when the precoding and decoding matrices obtained from the intermediate iterations are sufficiently close to their convergence values. Based on this important property, the proposed DQO algorithm employs the line search procedure so that it can converge to the destination directly. In addition, the optimal step size can be determined analytically by optimizing a quartic function. Numerical results show that the proposed DQO algorithm can suppress the interference leakage more rapidly than the traditional AMIL algorithm, and can achieve the same level of sum rate as that of AMIL algorithm with far less iterations and execution time.
A Rapid Convergent Low Complexity Interference Alignment Algorithm for Wireless Sensor Networks.
Jiang, Lihui; Wu, Zhilu; Ren, Guanghui; Wang, Gangyi; Zhao, Nan
2015-07-29
Interference alignment (IA) is a novel technique that can effectively eliminate the interference and approach the sum capacity of wireless sensor networks (WSNs) when the signal-to-noise ratio (SNR) is high, by casting the desired signal and interference into different signal subspaces. The traditional alternating minimization interference leakage (AMIL) algorithm for IA shows good performance in high SNR regimes, however, the complexity of the AMIL algorithm increases dramatically as the number of users and antennas increases, posing limits to its applications in the practical systems. In this paper, a novel IA algorithm, called directional quartic optimal (DQO) algorithm, is proposed to minimize the interference leakage with rapid convergence and low complexity. The properties of the AMIL algorithm are investigated, and it is discovered that the difference between the two consecutive iteration results of the AMIL algorithm will approximately point to the convergence solution when the precoding and decoding matrices obtained from the intermediate iterations are sufficiently close to their convergence values. Based on this important property, the proposed DQO algorithm employs the line search procedure so that it can converge to the destination directly. In addition, the optimal step size can be determined analytically by optimizing a quartic function. Numerical results show that the proposed DQO algorithm can suppress the interference leakage more rapidly than the traditional AMIL algorithm, and can achieve the same level of sum rate as that of AMIL algorithm with far less iterations and execution time.
International Nuclear Information System (INIS)
Pordt, A.
1985-10-01
The author describes the Mayer expansion in Euclidean lattice field theory by comparing it with the statistical mechanics of polymer systems. In this connection he discusses the Borel summability and the analyticity of the activities on the lattice. Furthermore the relations between renormalization and the Mayer expansion are considered. (HSI)
Rapid, global demographic expansions after the origins of agriculture.
Gignoux, Christopher R; Henn, Brenna M; Mountain, Joanna L
2011-04-12
The invention of agriculture is widely assumed to have driven recent human population growth. However, direct genetic evidence for population growth after independent agricultural origins has been elusive. We estimated population sizes through time from a set of globally distributed whole mitochondrial genomes, after separating lineages associated with agricultural populations from those associated with hunter-gatherers. The coalescent-based analysis revealed strong evidence for distinct demographic expansions in Europe, southeastern Asia, and sub-Saharan Africa within the past 10,000 y. Estimates of the timing of population growth based on genetic data correspond neatly to dates for the initial origins of agriculture derived from archaeological evidence. Comparisons of rates of population growth through time reveal that the invention of agriculture facilitated a fivefold increase in population growth relative to more ancient expansions of hunter-gatherers.
Rapid intraoperative tissue expansion with Foley catheter in a challenging cripple Hypospadias
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Murat Cakmak
2015-06-01
Full Text Available ABSTRACTFailed hypospadiass cases may result in hypovascular, scarred penis with residual penile chordee and leave the patient with minimal residual skin for penile resurfacing and urethroplasty. Local tissue expansion has become a good alternative to provide skin for penis by using expanders however they require long periods of time for expansion. Besides, rapid tissue expansion was also described in different tissues. We used rapid intraoperative expansion technique by using a Foley catheter in a failed hypospadias case who had minimal residual skin secondary to infection and we concluded that rapid intraoperative tissue expansion with Foley catheter is an effective, feasible reconstructive method for easy dissection and penile resurfacing in failed hypospadiass cases.
The Effects of Surgical Rapid Maxillary Expansion (SRME) on Vowel Formants
Sari, Emel; Kilic, Mehmet Akif
2009-01-01
The objective of this study was to investigate the effect of surgical rapid maxillary expansion (SRME) on vowel production. The subjects included 12 patients, whose speech were considered perceptually normal, that had undergone surgical RME for expansion of a narrow maxilla. They uttered the following Turkish vowels, ([a], [[epsilon
Photographic assessment of nasal morphology following rapid maxillary expansion in children
da SILVA FILHO, Omar Gabriel; LARA, Tulio Silva; AYUB, Priscila Vaz; OHASHI, Amanda Sayuri Cardoso; BERTOZ, Francisco Antônio
2011-01-01
Objective The aim of the present study was to use facial analysis to determine the effects of rapid maxillary expansion (RME) on nasal morphology in children in the stages of primary and mixed dentition, with posterior cross-bite. Material and Methods Facial photographs (front view and profile) of 60 patients in the pre-expansion period, immediate post-expansion period and one year following rapid maxillary expansion with a Haas appliance were evaluated on 2 occasions by 3 experienced orthodontists independently, with a 2-week interval between evaluations. The examiners were instructed to assess nasal morphology and had no knowledge regarding the content of the study. Intraexaminer and interexaminer agreement (assessed using the Kappa statistic) was acceptable. Results From the analysis of the mode of the examiners' findings, no alterations in nasal morphology occurred regarding the following aspects: dorsum of nose, alar base, nasal width of middle third and nasal base. Alterations were only detected in the nasolabial angle in 1.64% of the patients between the pre-expansion and immediate post-expansion photographs. In 4.92% of the patients between the immediate post-expansion period and 1 year following expansion; and in 6.56% of the patients between the pre-expansion period and one year following expansion. Conclusion RME performed on children in stages of primary and mixed dentition did not have any impact on nasal morphology, as assessed using facial analysis. PMID:21986660
Rapid divergence and convergence of life-history in experimentally evolved Drosophila melanogaster.
Burke, Molly K; Barter, Thomas T; Cabral, Larry G; Kezos, James N; Phillips, Mark A; Rutledge, Grant A; Phung, Kevin H; Chen, Richard H; Nguyen, Huy D; Mueller, Laurence D; Rose, Michael R
2016-09-01
Laboratory selection experiments are alluring in their simplicity, power, and ability to inform us about how evolution works. A longstanding challenge facing evolution experiments with metazoans is that significant generational turnover takes a long time. In this work, we present data from a unique system of experimentally evolved laboratory populations of Drosophila melanogaster that have experienced three distinct life-history selection regimes. The goal of our study was to determine how quickly populations of a certain selection regime diverge phenotypically from their ancestors, and how quickly they converge with independently derived populations that share a selection regime. Our results indicate that phenotypic divergence from an ancestral population occurs rapidly, within dozens of generations, regardless of that population's evolutionary history. Similarly, populations sharing a selection treatment converge on common phenotypes in this same time frame, regardless of selection pressures those populations may have experienced in the past. These patterns of convergence and divergence emerged much faster than expected, suggesting that intermediate evolutionary history has transient effects in this system. The results we draw from this system are applicable to other experimental evolution projects, and suggest that many relevant questions can be sufficiently tested on shorter timescales than previously thought. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.
Compressive sampling of polynomial chaos expansions: Convergence analysis and sampling strategies
International Nuclear Information System (INIS)
Hampton, Jerrad; Doostan, Alireza
2015-01-01
Sampling orthogonal polynomial bases via Monte Carlo is of interest for uncertainty quantification of models with random inputs, using Polynomial Chaos (PC) expansions. It is known that bounding a probabilistic parameter, referred to as coherence, yields a bound on the number of samples necessary to identify coefficients in a sparse PC expansion via solution to an ℓ 1 -minimization problem. Utilizing results for orthogonal polynomials, we bound the coherence parameter for polynomials of Hermite and Legendre type under their respective natural sampling distribution. In both polynomial bases we identify an importance sampling distribution which yields a bound with weaker dependence on the order of the approximation. For more general orthonormal bases, we propose the coherence-optimal sampling: a Markov Chain Monte Carlo sampling, which directly uses the basis functions under consideration to achieve a statistical optimality among all sampling schemes with identical support. We demonstrate these different sampling strategies numerically in both high-order and high-dimensional, manufactured PC expansions. In addition, the quality of each sampling method is compared in the identification of solutions to two differential equations, one with a high-dimensional random input and the other with a high-order PC expansion. In both cases, the coherence-optimal sampling scheme leads to similar or considerably improved accuracy
Compressive sampling of polynomial chaos expansions: Convergence analysis and sampling strategies
Hampton, Jerrad; Doostan, Alireza
2015-01-01
Sampling orthogonal polynomial bases via Monte Carlo is of interest for uncertainty quantification of models with random inputs, using Polynomial Chaos (PC) expansions. It is known that bounding a probabilistic parameter, referred to as coherence, yields a bound on the number of samples necessary to identify coefficients in a sparse PC expansion via solution to an ℓ1-minimization problem. Utilizing results for orthogonal polynomials, we bound the coherence parameter for polynomials of Hermite and Legendre type under their respective natural sampling distribution. In both polynomial bases we identify an importance sampling distribution which yields a bound with weaker dependence on the order of the approximation. For more general orthonormal bases, we propose the coherence-optimal sampling: a Markov Chain Monte Carlo sampling, which directly uses the basis functions under consideration to achieve a statistical optimality among all sampling schemes with identical support. We demonstrate these different sampling strategies numerically in both high-order and high-dimensional, manufactured PC expansions. In addition, the quality of each sampling method is compared in the identification of solutions to two differential equations, one with a high-dimensional random input and the other with a high-order PC expansion. In both cases, the coherence-optimal sampling scheme leads to similar or considerably improved accuracy.
Convergence of Mayer and Virial expansions and the Penrose tree-graph identity
Procacci, Aldo; Yuhjtman, Sergio A.
2017-01-01
We establish new lower bounds for the convergence radius of the Mayer series and the Virial series of a continuous particle system interacting via a stable and tempered pair potential. Our bounds considerably improve those given by Penrose (J Math Phys 4:1312, 1963) and Ruelle (Ann Phys 5:109-120, 1963) for the Mayer series and by Lebowitz and Penrose (J Math Phys 7:841-847, 1964) for the Virial series. To get our results, we exploit the tree-graph identity given by Penrose (Statistical mechanics: foundations and applications. Benjamin, New York, 1967) using a new partition scheme based on minimum spanning trees.
Rapid Expansion of Phenylthiocarbamide Non-Tasters among Japanese Macaques.
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Nami Suzuki-Hashido
Full Text Available Bitter taste receptors (TAS2R proteins allow mammals to detect and avoid ingestion of toxins in food. Thus, TAS2Rs play an important role in food choice and are subject to complex natural selection pressures. In our previous study, we examined nucleotide variation in TAS2R38, a gene expressing bitter taste receptor for phenylthiocarbamide (PTC, in 333 Japanese macaques (Macaca fuscata from 9 local populations in Japan. We identified a PTC "non-taster" TAS2R38 allele in Japanese macaques that was caused by a loss of the start codon. This PTC non-taster allele was only found in a limited local population (the Kii area, at a frequency of 29%. In this study, we confirmed that this allele was present in only the Kii population by analyzing an additional 264 individuals from eight new populations. Using cellular and behavioral experiments, we found that this allele lost its receptor function for perceiving PTC. The nucleotide sequences of the allele including flanking regions (of about 10 kb from 23 chromosomes were identical, suggesting that a non-taster allele arose and expanded in the Kii population during the last 13,000 years. Genetic analyses of non-coding regions in Kii individuals and neighboring populations indicated that the high allele frequency in the Kii population could not be explained by demographic history, suggesting that positive selection resulted in a rapid increase in PTC non-tasters in the Kii population. The loss-of-function that occurred at the TAS2R38 locus presumably provided a fitness advantage to Japanese macaques in the Kii population. Because TAS2R38 ligands are often found in plants, this functional change in fitness is perhaps related to feeding habit specificity. These findings should provide valuable insights for elucidating adaptive evolutionary changes with respect to various environments in wild mammals.
Position and stability of the mandibular incisors after rapid maxillary expansion
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Darcy Flávio Nouer
Full Text Available Objective: To make a cephalometric evaluation of the position and stability of the mandibular incisors immediately after rapid maxillaryexpansion and after a containment period of five months. Methods: The sample consisted of 21 schoolchildren, aged between 6 years and 11 months and 11 years, with mixed dentition, posterior reverse articulation (posterior cross bite, and erupted permanent first molars. The children were randomly divided into two groups: Group1 (composed of eleven children, in whom the encapsulated rapid maxilla expander was used, and Group 2 (composed of ten children, inwhom the conventional Hyrax expander was used. Three lateral teleradiographs of each individual were taken: before treatment, after rapid maxillary expansion, and after a containment period of five months. The cephalometric measurements used for analyzing the incisors were: /1.NB, /1-NB, /1-Line I, IMPA and /1-Jr. The data were submitted to the Dalhberg test, to calculate the error of repeatability, and to ANOVA (p<0.05. Results: The result showed significant difference between the adopted mechanics, but showed no difference between the initial measures, those after rapid expansion of the maxilla and final measures for all the distances, except for /1-Jr. Conclusion: Rapid maxillary expansion, using the encapsulated appliance or Hyrax, caused no significant alteration in the distances: /1.NB, /1-NB, /1-Line I, IMPA; before, after rapid maxillary expansion and after containment.
International Nuclear Information System (INIS)
Muzinich, I.J.
1980-01-01
The quark model of hadrons, when all constituents and gluons are included, has the possibility of accommodating not only what are conventionally accepted quark model states but also exotics of various kinds and eventually nuclei themselves. Recently, a considerable theoretical framework has evolved around quarks and gluons known as quantum chromodynamics. This theory is still at a primitive level as far as our ability to perform calculations. However, it is the only possible field theory that contains any hope of understanding both quark freedom at high energies and their strong binding within hadrons. I present a possible viewpoint on how both features could be true without apparent conflict. I also make some speculation on the nature of the perturbation expansion in such a world. What these speculations lack in originally I hope is compensated for by clarity
Robiony, M; Demitri, V; Costa, F; Politi, M; Cugini, U
1998-10-01
We present our experience of transcutaneous truncal anaesthesia of the maxillary nerve in association with transmucosal anaesthesia of the sphenopalatine ganglion in surgically assisted rapid maxillary expansion. Twelve patients with a skeletal transverse discrepancy of the maxilla were treated in our department from 1994 to 1995. Maxillary transcutaneous nerve block was done with a Quincke 8 cm spinal needle together with transmucosal anaesthesia of the sphenopalatine ganglion. Mepivacaine without adrenaline and sodium bicarbonate 1/10 was used for truncal anaesthesia and lidocaine-prilocaine cream for transmucosal anaesthesia. A Le Fort I osteotomy, lateral nasal wall osteotomy, pterygomaxillary osteotomy, and a palatal osteotomy were done for all patients before the maxillary expansion. Total anaesthesia of the maxillary area facilitated the operations and appreciably reduced the amount of postoperative pain. The ease of achieving effective anaesthesia before and after operation and the absence of side-effects make this form of anaesthetic particularly useful in surgically assisted rapid maxillary expansion.
Rapid expansion method (REM) for time‐stepping in reverse time migration (RTM)
Pestana, Reynam C.; Stoffa, Paul L.
2009-01-01
an analytical approximation for the Bessel function where we assume that the time step is sufficiently small. From this derivation we find that if we consider only the first two Chebyshev polynomials terms in the rapid expansion method we can obtain the second
Stability of rapid maxillary expansion and facemask therapy: a long-term controlled study.
Masucci, Caterina; Franchi, Lorenzo; Defraia, Efisio; Mucedero, Manuela; Cozza, Paola; Baccetti, Tiziano
2011-10-01
The aim of this prospective controlled study was to evaluate the long-term effects of rapid maxillary expansion and facemask therapy in Class III subjects. Twenty-two subjects (9 boys, 13 girls; mean age, 9.2 years ± 1.6) with Class III disharmony were treated consecutively with rapid maxillary expansion and facemask therapy followed by fixed appliances. The patients were reevaluated at the end of the 2-phase treatment (mean age, 14.5 years ± 1.9) and then recalled about 8.5 years after the end of rapid maxillary expansion and facemask treatment (mean age, 18.7 years ± 2.1). Two groups of controls with untreated Class III malocclusion were used for statistical comparisons of the short-term and long-term intervals. Statistical comparisons were performed with the Mann-Whitney U test. In the long term, no significant differences in maxillary changes were recorded, whereas the treatment group showed significantly smaller increases in mandibular protrusion. The sagittal maxillomandibular skeletal variables maintained significant improvements in the treatment group vs the control groups. In the long term, rapid maxillary expansion and facemask therapy led to successful outcomes in about 73% of the Class III patients. Favorable skeletal changes were mainly due to significant improvements in the sagittal position of the mandible. Copyright © 2011 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.
Over the past 10,000 years, humans have facilitated rapid range expansions of animal, plants and microorganisms, often accompanying agriculture’s spread. Three squash species were early domesticates in the New World. Their spreading cultivation out of the Southwest across much of today’s USA has bee...
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Daniel Santos Fonseca Figueiredo
Full Text Available ABSTRACT Introduction: The aim of this study was to evaluate the skeletal and dental effects of rapid maxillary expansion (RME in cleft patients using two types of expanders. Methods: Twenty unilateral cleft lip and palate patients were randomly divided into two groups, according to the type of expander used: (I modified Hyrax and (II inverted Mini-Hyrax. A pretreatment cone-beam computed tomographic image (T0 was taken as part of the initial orthodontic records and three months after RME as need for bone graft planning (T1. Results: In general, there was no significant difference among groups (p > 0.05. Both showed significant transverse maxillary expansion (p 0.05. There was greater crown than apical expansion. Maxillary posterior expansion tended to be larger than anterior opening (p 0.05. Conclusions: The appliances tested are effective for transverse expansion of the maxilla. However, these appliances should be better indicated to cleft cases also presenting posterior transverse discrepancy, since there was greater expansion in the posterior maxillary region than in the anterior one.
Modified hyrax splint for rapid maxillary expansion in esthetically concerned patients
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Sarabjeet Singh Sandhu
2015-01-01
Full Text Available The orthodontic treatment of Class III malocclusion with a maxillary deficiency is often treated with maxillary protraction either with or without maxillary expansion. The routine procedure for rapid maxillary expansion includes banding on first premolars/first deciduous molars and the permanent first molars. However in some patients who are esthetically very conscious, banding of the first premolar would not be a good esthetic option. So for such circumstances we have designed a modified hyrax splint, which does not need the first premolars to be banded.
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Retno Dewati
2014-06-01
Full Text Available Background: Children with anterior and posterior crossbite usually have a complaint in aesthetic and masticatory function. It could caused by bad habits and hereditary factors which made worse condition. Purpose: The purpose of this case report was to report the use of orthodontic appliance rapid maxillary expansion (RPE and intermaxillary elastic to correct posterior and anterior crossbite in teenage patient. Case: A fourteen years-old teenage female patient came to Dental Hospital Dentistry Universitas Airlangga with case of anterior posterior cross bite and unerupted permanent teeth. Case management: The case was treated using orthodontic fixed appliance rapid maxillary expansion (RPE and followed by intermaxillary elastics. The posterior cross bite treatment took 4 weeks used of orthodontic fixed appliance RPE, while, treatment of anterior cross bite which used intermaxillary elactic was done within three month to achieved normal occlusion. Conclusion: This case report showed that the orthodontic appliance rapid maxillary expansion (RPE and intermaxillary elastic could be used to correct posterior and anterior crossbite.Latar belakang: Anak dengan gigitan terbalik anterior dan posterior pada umumnya mempunyai keluhan dalam hal estetik dan fungsi pengunyahan. Kondisi gigitan terbalik biasanya disebabkan oleh adanya kebiasaan buruk dan faktor keturunan yang semakin memperparah keadaan tersebut. Tujuan: Laporan kasus ini melaporkan pemakaian alat cekat rapid maxillary expansion (RPE dan elastik intermaksila untuk mengkoreksi gigitan terbalik posterior dan anterior pada anak remaja. Kasus: Pasien remaja perempuan berusia 14 tahun datang ke Rumah Sakit Gigi dan Mulut Fakultas Kedokteran Gigi Universitas Airlangga Surabaya dengan kasus gigitan terbalik anterior posterior dan terdapat gigi permanen yang tidak tumbuh. Tatalaksana kasus: Perawatan yang dilakukan adalah koreksi gigitan terbalik dengan menggunakan alat ortodonsia cekat rapid maxillary
Liang, Di; Zhang, Donglan; Huang, Jiayan; Schweitzer, Stuart
2016-01-01
China's rapid and sustained economic growth offers an opportunity to ask whether the advantages of growth diffuse throughout an economy, or remain localized in areas where the growth has been the greatest. A critical policy area in China has been the health system, and health inequality has become an issue that has led the government to broaden national health insurance programs. This study investigates whether health system resources and performance have converged over the past 30 years across China's 31 provinces. To examine geographic variation of health system resources and performance at the provincial level, we measure the degree of sigma convergence and beta convergence in indicators of health system resources (structure), health services utilization (process), and outcome. All data are from officially published sources: the China Health Statistics Year Book and the China Statistics Year Book. Sigma convergence is found for resource indicators, whereas it is not observed for either process or outcome indicators, indicating that disparities only narrowed in health system resources. Beta convergence is found in most indicators, except for 2 procedure indicators, reflecting that provinces with poorer resources were catching up. Convergence found in this study probably reflects the mixed outcome of government input, and market forces. Thus, left alone, the equitable distribution of health care resources may not occur naturally during a period of economic growth. Governmental and societal efforts are needed to reduce geographic health variation and promote health equity. © The Author(s) 2016.
Three-Dimensional Force Measurements During Rapid Palatal Expansion in Sus scrofa
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Kelly Goeckner
2016-04-01
Full Text Available Rapid palatal expansion is an orthodontic procedure widely used to correct the maxillary arch. However, its outcome is significantly influenced by factors that show a high degree of variability amongst patients. The traditional treatment methodology is based on an intuitive and heuristic treatment approach because the forces applied in the three dimensions are indeterminate. To enable optimal and individualized treatment, it is essential to measure the three-dimensional (3D forces and displacements created by the expander. This paper proposes a method for performing these 3D measurements using a single embedded strain sensor, combining experimental measurements of strain in the palatal expander with 3D finite element analysis (FEA. The method is demonstrated using the maxillary jaw from a freshly euthanized pig (Sus scrofa and a hyrax-design rapid palatal expander (RPE appliance with integrated strain gage. The strain gage measurements are recorded using a computer interface, following which the expansion forces and extent of expansion are estimated by FEA. A total activation of 2.0 mm results in peak total force of about 100 N—almost entirely along the direction of expansion. The results also indicate that more than 85% of the input activation is immediately transferred to the palate and/or teeth. These studies demonstrate a method for assessing and individualizing expansion magnitudes and forces during orthopedic expansion of the maxilla. This provides the basis for further development of smart orthodontic appliances that provide real-time readouts of forces and movements, which will allow personalized, optimal treatment.
Novel micronisation β-carotene using rapid expansion supercritical solution with co-solvent
Kien, Le Anh
2017-09-01
Rapid expansion of supercritical solution (RESS) is the most common approach of pharmaceutical pacticle forming methods using supercritical fluids. The RESS method is a technology producing a small solid product with a very narrow particle size distribution, organic solvent-free particles. This process is also simple and easy to control the operating parameters in comparision with other ways based on supercritical techniques. In this study, β-carotene, a strongly colored red-orange pigment abundant in plants and fruits, has been forming by RESS. In addition, the size and morphology effect of four different RESS parameters including co-solvent, extraction temperature, and extraction pressure and expansion nozzle temperature has surveyed. The particle size distribution has been determined by using laser diffraction experiment. SEM has conducted to analyze the surface structure, DSC and FTIR for thermal and chemical structure analysis.
Ileri, Zehra; Basciftci, Faruk Ayhan
2015-03-01
To investigate the short-term effects of the asymmetric rapid maxillary (ARME) appliance on the vertical, sagittal, and transverse planes in patients with true unilateral posterior crossbite. Subjects were divided into two groups. The treatment group was comprised of 21 patients with unilateral posterior crossbite (mean age = 13.3 ± 2.1 years). Members of this group were treated with the ARME appliance. The control group was comprised of 17 patients with Angle Class I who were kept under observation (mean age = 12.3 ± 0.8 years). Lateral and frontal cephalograms were taken before the expansion (T1), immediately after expansion (T2), and at postexpansion retention (T3) in the treatment group and at preobservation (T1) and postobservation (T2) in the control group. A total of 34 measurements were assessed on cephalograms. For statistical analysis, the Wilcoxon test and analysis of covariance were used. The ARME appliance produced significant increases in nasal, maxillary base, upper arch, and lower arch dimensions (P ARME appliance created asymmetric increments in the transversal dimensions of the nose, maxilla, and upper arch in the short term. Asymmetric expansion therapy for subjects with unilateral maxillary deficiency may provide satisfactory outcomes in adolescents, with the exception of mandibular arch expansion. The triangular pattern of expansion caused clockwise rotation of the mandible and the occlusal plane and produced significant alterations in the vertical facial dimensions, whereas it created no displacement in maxilla in the sagittal plane.
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Myungrip Kim
2014-06-01
Full Text Available This case report shows that orthodontic treatment with rapid maxillary expansion (RME is an effective treatment option for managing pediatric obstructive sleep apnea (OSA. An 11-year-old boy with severe pediatric OSA received comprehensive orthodontic treatment with RME. Four sleep studies were done: before orthodontic treatment, after RME, just after comprehensive orthodontic treatment and at the 2-year and 5-month follow-up. Polysomnographic findings showed that the orthodontic treatment with RME was successful for managing severe OSA in the patient.
Mutinelli, Sabrina; Manfredi, Mario; Guiducci, Antonio; Denotti, Gloria; Cozzani, Mauro
2015-01-01
Background Anchorage onto permanent dentition is a common procedure in rapid maxillary expansion. However, replacing first permanent molars with the second deciduous molars seems to be an option to reduce some negative side effects during orthodontic treatment. The purpose of this study was to evaluate the dental effect of rapid maxillary expansion with anchorage exclusively onto deciduous teeth performed in the first period of transition. Methods Twenty patients with a lateral cross-bite tre...
Efficient 3D frequency response modeling with spectral accuracy by the rapid expansion method
Chu, Chunlei
2012-07-01
Frequency responses of seismic wave propagation can be obtained either by directly solving the frequency domain wave equations or by transforming the time domain wavefields using the Fourier transform. The former approach requires solving systems of linear equations, which becomes progressively difficult to tackle for larger scale models and for higher frequency components. On the contrary, the latter approach can be efficiently implemented using explicit time integration methods in conjunction with running summations as the computation progresses. Commonly used explicit time integration methods correspond to the truncated Taylor series approximations that can cause significant errors for large time steps. The rapid expansion method (REM) uses the Chebyshev expansion and offers an optimal solution to the second-order-in-time wave equations. When applying the Fourier transform to the time domain wavefield solution computed by the REM, we can derive a frequency response modeling formula that has the same form as the original time domain REM equation but with different summation coefficients. In particular, the summation coefficients for the frequency response modeling formula corresponds to the Fourier transform of those for the time domain modeling equation. As a result, we can directly compute frequency responses from the Chebyshev expansion polynomials rather than the time domain wavefield snapshots as do other time domain frequency response modeling methods. When combined with the pseudospectral method in space, this new frequency response modeling method can produce spectrally accurate results with high efficiency. © 2012 Society of Exploration Geophysicists.
Baka, Zeliha Muge; Akin, Mehmet; Ucar, Faruk Izzet; Ileri, Zehra
2015-01-01
The aims of this study were to quantitatively evaluate the changes in arch widths and buccolingual inclinations of the posterior teeth after asymmetric rapid maxillary expansion (ARME) and to compare the measurements between the crossbite and the noncrossbite sides with cone-beam computed tomography (CBCT). From our clinic archives, we selected the CBCT records of 30 patients with unilateral skeletal crossbite (13 boys, 14.2 ± 1.3 years old; 17 girls, 13.8 ± 1.3 years old) who underwent ARME treatment. A modified acrylic bonded rapid maxillary expansion appliance including an occlusal locking mechanism was used in all patients. CBCT records had been taken before ARME treatment and after a 3-month retention period. Fourteen angular and 80 linear measurements were taken for the maxilla and the mandible. Frontally clipped CBCT images were used for the evaluation. Paired sample and independent sample t tests were used for statistical comparisons. Comparisons of the before-treatment and after-retention measurements showed that the arch widths and buccolingual inclinations of the posterior teeth increased significantly on the crossbite side of the maxilla and on the noncrossbite side of the mandible (P ARME treatment, the crossbite side of the maxilla and the noncrossbite side of the mandible were more affected than were the opposite sides. Copyright © 2015. Published by Elsevier Inc.
Rapid expansion method (REM) for time‐stepping in reverse time migration (RTM)
Pestana, Reynam C.
2009-01-01
We show that the wave equation solution using a conventional finite‐difference scheme, derived commonly by the Taylor series approach, can be derived directly from the rapid expansion method (REM). After some mathematical manipulation we consider an analytical approximation for the Bessel function where we assume that the time step is sufficiently small. From this derivation we find that if we consider only the first two Chebyshev polynomials terms in the rapid expansion method we can obtain the second order time finite‐difference scheme that is frequently used in more conventional finite‐difference implementations. We then show that if we use more terms from the REM we can obtain a more accurate time integration of the wave field. Consequently, we have demonstrated that the REM is more accurate than the usual finite‐difference schemes and it provides a wave equation solution which allows us to march in large time steps without numerical dispersion and is numerically stable. We illustrate the method with post and pre stack migration results.
Impact of rapid maxillary expansion on nasomaxillary complex volume in mouth-breathers
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Mario Cappellette Jr.
Full Text Available ABSTRACT Objective: To assess the volumetric changes that occur in the nasomaxillary complex of mouth-breathing patients with transverse maxillary deficiency subjected to rapid maxillary expansion (RME. Methods: This was a controlled, prospective intervention study involving 38 mouth-breathing patients presenting with transverse maxillary deficiency, regardless of malocclusion type or race. Twenty-three of them comprised the experimental group, which was composed of 11 (47.8% boys, and 12 (52.2% girls, with a mean age of 9.6 years, ranging from 6.4 to 14.2 years and standard deviation of 2.3 years; and 15 of them comprised the control group, composed of 9 (60% boys and 6 (40% girls with an mean age of 10.5 years, ranging from 8.0 to 13.6 years, and standard deviation of 1.9 years. All patients were scanned (CT according to a standard protocol: Initial CT (T1, and CT three months thereafter (T2, and the patients in the experimental group were treated with RME using a Hyrax expander for the correction of maxillary deficiency during the T1-T2 interval. The CT scans were manipulated using Dolphin® Imaging version 11.7 software for total and partial volumetric assessment of the nasomaxillary complex. Results: The results revealed that in the experimental group there was a significant increase in the size of the structures of interest compared to the control group, both in general aspect and in specific regions. Conclusions: Rapid maxillary expansion (RME provided a significant expansion in all the structures of the nasomaxillary complex (nasal cavity, oropharynx, right and left maxillary sinuses.
Protecting tropical forests from the rapid expansion of rubber using carbon payments.
Warren-Thomas, Eleanor M; Edwards, David P; Bebber, Daniel P; Chhang, Phourin; Diment, Alex N; Evans, Tom D; Lambrick, Frances H; Maxwell, James F; Nut, Menghor; O'Kelly, Hannah J; Theilade, Ida; Dolman, Paul M
2018-03-02
Expansion of Hevea brasiliensis rubber plantations is a resurgent driver of deforestation, carbon emissions, and biodiversity loss in Southeast Asia. Southeast Asian rubber extent is massive, equivalent to 67% of oil palm, with rapid further expansion predicted. Results-based carbon finance could dis-incentivise forest conversion to rubber, but efficacy will be limited unless payments match, or at least approach, the costs of avoided deforestation. These include opportunity costs (timber and rubber profits), plus carbon finance scheme setup (transaction) and implementation costs. Using comprehensive Cambodian forest data, exploring scenarios of selective logging and conversion, and assuming land-use choice is based on net present value, we find that carbon prices of $30-$51 per tCO 2 are needed to break even against costs, higher than those currently paid on carbon markets or through carbon funds. To defend forests from rubber, either carbon prices must be increased, or other strategies are needed, such as corporate zero-deforestation pledges, and governmental regulation and enforcement of forest protection.
Rapid maxillary expansion effects: An alternative assessment method by means of cone-beam tomography
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Camilo Aquino Melgaço
2014-10-01
Full Text Available INTRODUCTION: This study aims to develop a method to assess the changes in palatal and lingual cross-sectional areas in patients submitted to rapid maxillary expansion (RME. METHODS: The sample comprised 31 Class I malocclusion individuals submitted to RME and divided into two groups treated with Haas (17 patients and Hyrax (14 patients expanders. Cone-beam computed tomography scans were acquired at T0 (before expansion and T1 (six months after screw stabilization. Maxillary and mandibular cross-sectional areas were assessed at first permanent molars and first premolars regions and compared at T0 and T1. Mandibular occlusal area was also analyzed. RESULTS: Maxillary cross-sectional areas increased in 56.18 mm2 and 44.32 mm2 for the posterior and anterior regions. These values were smaller for the mandible, representing augmentation of 40.32 mm2 and 39.91 mm2 for posterior and anterior sections. No differences were found when comparing both expanders. Mandibular occlusal area increased 43.99mm2 and mandibular incisors proclined. Increments of 1.74 mm and 1.7 mm occurred in mandibular intermolar and interpremolar distances. These same distances presented increments of 5.5 mm and 5.57 mm for the maxillary arch. CONCLUSION: Occlusal and cross-sectional areas increased significantly after RME. The method described seems to be reliable and precise to assess intraoral area changes.
Miniscrew-assisted rapid palatal expansion for managing arch perimeter in an adult patient
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Amanda Carneiro da Cunha
Full Text Available ABSTRACT Introduction: Etiology of dental crowding may be related to arch constriction in diverse dimensions, and an appropriate manipulation of arch perimeter by intervening in basal bone discrepancies cases, may be a key for crowding relief, especially when incisors movement is limited due to underlying pathology, periodontal issues or restrictions related to soft tissue profile. Objectives: This case report illustrates a 24-year old woman, with maxillary transverse deficiency, upper and lower arches crowding, Class II, division 1, subdivision right relationship, previous upper incisors traumatic episode and straight profile. A non-surgical and non-extraction treatment approach was feasible due to the miniscrew-assisted rapid palatal expansion technique (MARPE. Methods: The MARPE appliance consisted of a conventional Hyrax expander supported by four orthodontic miniscrews. A slow expansion protocol was adopted, with an overall of 40 days of activation and a 3-month retention period. Intrusive traction miniscrew-anchored mechanics were used for correcting the Class II subdivision relationship, managing lower arch perimeter and midline deviation before including the upper central incisors. Results: Post-treatment records show an intermolar width increase of 5 mm, bilateral Class I molar and canine relationships, upper and lower crowding resolution, coincident dental midlines and proper intercuspation. Conclusions: The MARPE is an effective treatment approach for managing arch-perimeter deficiencies related to maxillary transverse discrepancies in adult patients.
Siqueira, Danilo Furquim; Cardoso, Mauricio de Almeida; Capelozza, Leopoldino; Goldenberg, Dov Charles; Fernandes, Mariana dos Santos
2015-01-01
OBJECTIVE: The present study assessed the maxillary dental arch changes produced by surgically assisted rapid maxillary expansion (SARME). METHODS: Dental casts from 18 patients (mean age of 23.3 years) were obtained at treatment onset (T1), three months after SARME (T2) and 6 months after expansion (T3). The casts were scanned in a 3D scanner (D-250, 3Shape, Copenhagen, Denmark). Maxillary dental arch width, dental crown tipping and height were measured and assessed by ANOVA and Tukey's test. RESULTS: Increased transversal widths from T1 and T2 and the maintenance of these values from T2 and T3 were observed. Buccal teeth tipping also showed statistically significant differences, with an increase in all teeth from T1 to T2 and a decrease from T2 to T3. No statistically significant difference was found for dental crown height, except for left first and second molars, although clinically irrelevant. CONCLUSION: SARME proved to be an effective and stable procedure, with minimum periodontal hazards. PMID:26154457
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Emine AKBAŞ
2017-10-01
Full Text Available Purpose: The purpose of this study was to evaluate the efficacy of tranexamic acid (TXA in reducing blood loss during surgically assisted rapid palatal expansion (SARPE procedure. Subjects and Methods: A total of 34 patients (12 male, 22 female who had been treated surgically under general anesthesia with SARPE including pterygoid disjunction for transverse maxillary deficiency (TMD were included in this study. The study group (n=17 received intravenous (IV TXA 10 mg/kg as a preoperative bolus; the control group (n=17 received normal saline solution. Preoperative and postoperative haemoglobin and haematocrit values, intraoperative blood loss, and any blood product transfusion were recorded. Results: Blood loss during SARPE was statistically significantly less in the study group than the control group (p=0.0001. Conclusion: Preoperative IV administration of TXA can effectively control blood loss during when SARPE with pterygoid disjunction is performed.
A Case of Re-Expansion Pulmonary Edema after Rapid Pleural Evacuation
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SH Shahbazi
2007-07-01
Full Text Available Introduction & Objective: Pulmonary edema after chest tube insertion is a rare complication and is associated with high mortality. The cause of this phenomenon is not clear, although causes such as decrease in surfactant and inflammatory process have been defined. Early diagnosis and treatment decrease the mortality. This study introduces a case of re-expansion pulmonary edema after rapid pleural evacuation. Case: The case is a 4.5 y/o boy, a case of Tetralogy of Fallot, who developed respiratory distress after surgery (Total Correction in ICU of Namazi Hospital in 1385. Chest X ray showed pneumothorax of left lung. For the patient, chest tube was inserted and the symptoms improved. After few hours the patient developed tachypnea, tachycardia, and CXR showed pulmonary edema of left lung. Appropriate treatment was done for the patient and his condition improved. Conclusion: Pulmonary edema after sudden evacuation of pleura is a rare phenomenon and early diagnosis decreases the mortality.
Rapid evolution of phenology during range expansion with recent climate change.
Lustenhouwer, Nicky; Wilschut, Rutger A; Williams, Jennifer L; van der Putten, Wim H; Levine, Jonathan M
2018-02-01
Although climate warming is expected to make habitat beyond species' current cold range edge suitable for future colonization, this new habitat may present an array of biotic or abiotic conditions not experienced within the current range. Species' ability to shift their range with climate change may therefore depend on how populations evolve in response to such novel environmental conditions. However, due to the recent nature of thus far observed range expansions, the role of rapid adaptation during climate change migration is only beginning to be understood. Here, we evaluated evolution during the recent native range expansion of the annual plant Dittrichia graveolens, which is spreading northward in Europe from the Mediterranean region. We examined genetically based differentiation between core and edge populations in their phenology, a trait that is likely under selection with shorter growing seasons and greater seasonality at northern latitudes. In parallel common garden experiments at range edges in Switzerland and the Netherlands, we grew plants from Dutch, Swiss, and central and southern French populations. Population genetic analysis following RAD-sequencing of these populations supported the hypothesized central France origins of the Swiss and Dutch range edge populations. We found that in both common gardens, northern plants flowered up to 4 weeks earlier than southern plants. This differentiation in phenology extended from the core of the range to the Netherlands, a region only reached from central France over approximately the last 50 years. Fitness decreased as plants flowered later, supporting the hypothesized benefits of earlier flowering at the range edge. Our results suggest that native range expanding populations can rapidly adapt to novel environmental conditions in the expanded range, potentially promoting their ability to spread. © 2017 John Wiley & Sons Ltd.
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Brian LaBlonde
Full Text Available ABSTRACT Introduction: The aim of this multi-center retrospective study was to quantify the changes in alveolar bone height and thickness after using two different rapid palatal expansion (RPE activation protocols, and to determine whether a more rapid rate of expansion is likely to cause more adverse effects, such as alveolar tipping, dental tipping, fenestration and dehiscence of anchorage teeth. Methods: The sample consisted of pre- and post-expansion records from 40 subjects (age 8-15 years who underwent RPE using a 4-banded Hyrax appliance as part of their orthodontic treatment to correct posterior buccal crossbites. Subjects were divided into two groups according to their RPE activation rates (0.5 mm/day and 0.8 mm/day; n = 20 each group. Three-dimensional images for all included subjects were evaluated using Dolphin Imaging Software 11.7 Premium. Maxillary base width, buccal and palatal cortical bone thickness, alveolar bone height, and root angulation and length were measured. Significance of the changes in the measurements was evaluated using Wilcoxon signed-rank test and comparisons between groups were done using ANOVA. Significance was defined at p ≤ 0.05. Results: RPE activation rates of 0.5 mm per day (Group 1 and 0.8 mm per day (Group 2 caused significant increase in arch width following treatment; however, Group 2 showed greater increases compared to Group 1 (p < 0.01. Buccal alveolar height and width decreased significantly in both groups. Both treatment protocols resulted in significant increases in buccal-lingual angulation of teeth; however, Group 2 showed greater increases compared to Group 1 (p < 0.01. Conclusion: Both activation rates are associated with significant increase in intra-arch widths. However, 0.8 mm/day resulted in greater increases. The 0.8 mm/day activation rate also resulted in more increased dental tipping and decreased buccal alveolar bone thickness over 0.5 mm/day.
Baccetti, Tiziano; Mucedero, Manuela; Leonardi, Maria; Cozza, Paola
2009-11-01
Our aim in this prospective randomized clinical study was to assess the prevalence rate of eruption of palatally displaced canines, diagnosed at an early developmental stage with posteroanterior radiographs and consequently treated by rapid maxillary expansion. A sample of 60 subjects in the early mixed dentition with palatally displaced canines diagnosed on posteroanterior radiographs was enrolled in the trial. Their age range at the first observation (T1) was 7.6 to 9.6 years, with a prepubertal stage of skeletal maturity (CS1 or CS2). The 60 subjects were randomly allocated to the treatment group (TG, 35 subjects) or the no-treatment group (NTG, 25 subjects). The TG was treated with a banded rapid maxillary expander; after expansion, all patients were retained with the expander in place for 6 months. Thereafter, the expander was removed, and the patients wore a retention plate at night for a year. The NTG received no treatment. All subjects were reevaluated in the early permanent dentition (T2) (postpubertal CS4). The number of dropouts was recorded. The main outcome recorded at T2 was successful or unsuccessful eruption of the maxillary permanent canines. The starting forms at T1 for measurements on posteroanterior and panoramic films were compared in the 2 groups with the Mann-Whitney U test (P <0.05). The prevalence rates of successful and unsuccessful treatments in the TG were compared with those in NTG with chi-square tests (P <0.05). From T1 to T2, there were 3 dropouts in each group. The final sample comprised 32 subjects in the TG and 22 subjects in the NTG. No statistically significant differences were found for any variable at T1. The prevalence rates of successful eruption of the maxillary canines were 65.7% (21 subjects) in the TG and 13.6% (3 subjects) in the NTG. The comparison was statistically significant (chi-square = 12.4; P <0.001). Subjects with palatally displaced canines in the early mixed dentition do not have transverse deficiency of the
Rapidly converging bound state eigenenergies for the two dimensional quantum dipole
International Nuclear Information System (INIS)
Handy, C R; Vrinceanu, D
2013-01-01
We examine the effectiveness of a new spectral method in solving the two dimensional dipole problem (DP), as originally formulated by Dasbiswas et al (2010 Phys. Rev. B: At. Mol. Opt. Phys. 81 064516), and recently analysed by Amore and Fernandez (AF, 2012 Phys. Rev. B: At. Mol. Opt. Phys. 45 235004), through a large, non-orthogonal basis, Rayleigh–Ritz (RR) analysis. This deceptively simple problem has a long history of poorly approximated energy values, particularly for the ground state, until the recent work by AF. In contrast to their approach, we implement an orthogonal polynomial projection quantization (OPPQ) analysis (Handy and Vrinceanu 2013 J. Phys. A: Math. Theor. 46 135202), involving expanding the wavefunction in terms of a complete basis, Ψ( r-vector )=∑ n Ω n P n ( r-vector )R( r-vector ), where P n are the orthogonal polynomials relative to the weight R. For systems transformable into a moment equation, such as DP, the projection coefficients are determinable in closed form, yielding an efficient quantization procedure, particularly when the weight assumes the asymptotic form of the physical solutions. There are several theoretical reasons why the OPPQ should be more effective than the above RR approach. Indeed, comparable results are achieved with significantly fewer OPPQ variational parameters as compared to RR-variational parameters. For instance, with regards to the delicate ground state energy, 130 OPPQ variables are required to achieve E gr = −0.137 7614 (E gr = −0.137 7514 after a Shanks transform) as opposed to the 821 required within the RR formulation: E gr = −0.137 7478. Despite this, the relative slow convergence for low lying even parity states, within both the OPPQ and RR formulations, suggests that significant logarithmic contributions to the wavefunction, at the origin, have been ignored by all previous investigators. Modifying the RR variational analysis to include log-dependent basis, affirms this through an
International Nuclear Information System (INIS)
Grange, P.; Lejeune, A.
1979-01-01
Two, three- and four-body contributions to the binding energy of nuclear matter are evaluated in the framework of the Bethe-Brueckner expansion. Special attention is devoted to the choice of the auxillary single particle field and to the potential diagrams at the level of three- and four-hole lines present when such a field is different from zero. Two nucleon-nucleon interactions are used: a model interaction V 1 and the Reid soft-core interaction. For V 1 our results are compared with those obtained from variational calculations; this comparison supports the reliability of the perturbative expansion. (Auth.)
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Edna Namiko Izuka
2015-06-01
Full Text Available OBJECTIVE: To assess short-term tomographic changes in the upper airway dimensions and quality of life of mouth breathers after rapid maxillary expansion (RME. METHODS: A total of 25 mouth breathers with maxillary atresia and a mean age of 10.5 years old were assessed by means of cone-beam computed tomography (CBCT and a standardized quality of life questionnaire answered by patients' parents/legal guardians before and immediately after rapid maxillary expansion. RESULTS: Rapid maxillary expansion resulted in similar and significant expansion in the width of anterior (2.8 mm, p < 0.001 and posterior nasal floor (2.8 mm, p < 0.001. Although nasopharynx and nasal cavities airway volumes significantly increased (+1646.1 mm3, p < 0.001, oropharynx volume increase was not statistically significant (+1450.6 mm3, p = 0.066. The results of the quality of life questionnaire indicated that soon after rapid maxillary expansion, patients' respiratory symptoms significantly decreased in relation to their initial respiratory conditions. CONCLUSIONS: It is suggested that RME produces significant dimensional increase in the nasal cavity and nasopharynx. Additionally, it also positively impacts the quality of life of mouth-breathing patients with maxillary atresia.
Steinberg, Christian; Bröckelmann, Ann-Kathrin; Rehbein, Maimu; Dobel, Christian; Junghöfer, Markus
2013-03-01
Various pathway models for emotional processing suggest early prefrontal contributions to affective stimulus evaluation. Yet, electrophysiological evidence for such rapid modulations is still sparse. In a series of four MEG/EEG studies which investigated associative learning in vision and audition using a novel MultiCS Conditioning paradigm, many different neutral stimuli (faces, tones) were paired with aversive and appetitive events in only two to three learning instances. Electrophysiological correlates of neural activity revealed highly significant amplified processing for conditioned stimuli within distributed prefrontal and sensory cortical networks. In both, vision and audition, affect-specific responses occurred in two successive waves of rapid (vision: 50-80 ms, audition: 25-65 ms) and mid-latency (vision: >130 ms, audition: >100 ms) processing. Interestingly, behavioral measures indicated that MultiCS Conditioning successfully prevented contingency awareness. We conclude that affective processing rapidly recruits highly elaborate and widely distributed networks with substantial capacity for fast learning and excellent resolving power. Copyright © 2012 Elsevier B.V. All rights reserved.
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Maria de Fátima Batista de Melo
2013-01-01
Full Text Available Aims: To analyze the density of the midpalatal suture by means of digital radiographs three months after retention to evaluate if this period of retention is really sufficient for bone repair. Materials and Methods: This prospective study consisted of 31 patients (11 girls and 20 boys in the mixed or permanent dentition stage, treated using a tooth-tissue borne expanders (Haas. Occlusal digital radiographs were taken at three stages: prior to rapid maxillary expansion (Stage I; immediately after desired maxillary expansion (Stage II; and after three months of retention (Stage III. Radiographs were taken on a dental X-ray machine, set at 70 kVp and 7 mA with an exposure time of 0.04 s. A phosphor storage plate system, imaging plate size n. 2 (35 × 45 × 1.6 mm, was used. Three regions (A, B and C measured 0.02 mm² were selected for optical density analysis. The difference between the measurements was evaluated with the paired t-test. Results: The optical density was reduced at Stages II and III compared with Stage I. Between-stage comparison showed statistically significant changes for all variables (P < 0.05, with the highest mean optical density at Stage I and the lowest at Stage II, in all groups. Actually, there was an increase in optical density between Stages II and III, but they are reduced compared with Stage I. Conclusion: The results strongly suggest that bone formation did not occur as expected, and that a longer retention period for bone repair may be necessary.
Dental arch changes associated with rapid maxillary expansion: A retrospective model analysis study
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Ivor M D′Souza
2015-01-01
Full Text Available Introduction: Transverse deficiency of the maxilla is a common clinical problem in orthodontics and dentofacial orthopedics. Transverse maxillary deficiency, isolated or associated with other dentofacial deformities, results in esthetic and functional impairment giving rise to several clinical manifestations such as asymmetrical facial growth, positional and functional mandibular deviations, altered dentofacial esthetics, adverse periodontal responses, unstable dental tipping, and other functional problems. Orthopedic maxillary expansion is the preferred treatment approach to increase the maxillary transverse dimension in young patients by splitting of the mid palatal suture. This orthopedic procedure has lately been subject of renewed interest in orthodontic treatment mechanics because of its potential for increasing arch perimeter to alleviate crowding in the maxillary arch without adversely affecting facial profile. Hence, the present investigation was conducted to establish a correlation between transverse expansion and changes in the arch perimeter, arch width and arch length. Methods: For this purpose, 10 subjects (five males, five females were selected who had been treated by rapid maxillary expansion (RME using hyrax rapid palatal expander followed by fixed mechanotherapy (PEA. Pretreatment (T1, postexpansion (T2, and posttreatment (T3 dental models were compared for dental changes brought about by RME treatment and its stability at the end of fixed mechanotherapy. After model measurements were made, the changes between T1-T2, T2-T3 and T1-T3 were determined for each patient. The mean difference between T1-T2, T2-T3 and T1-T3 were compared to assess the effects of RME on dental arch measurements. Results are expressed as mean ± standard deviation and are compared by repeated measures analysis of variance followed by a post-hoc test. Arch perimeter changes are correlated with changes in arch widths at the canine, premolar and molar
Rapid expansion and pseudo spectral implementation for reverse time migration in VTI media
Pestana, Reynam C; Ursin, Bjø rn; Stoffa, Paul L
2012-01-01
In isotropic media, we use the scalar acoustic wave equation to perform reverse time migration (RTM) of the recorded pressure wavefield data. In anisotropic media, P- and SV-waves are coupled, and the elastic wave equation should be used for RTM. For computational efficiency, a pseudo-acoustic wave equation is often used. This may be solved using a coupled system of second-order partial differential equations. We solve these using a pseudo spectral method and the rapid expansion method (REM) for the explicit time marching. This method generates a degenerate SV-wave in addition to the P-wave arrivals of interest. To avoid this problem, the elastic wave equation for vertical transversely isotropic (VTI) media can be split into separate wave equations for P- and SV-waves. These separate wave equations are stable, and they can be effectively used to model and migrate seismic data in VTI media where |ε- δ| is small. The artifact for the SV-wave has also been removed. The independent pseudo-differential wave equations can be solved one for each mode using the pseudo spectral method for the spatial derivatives and the REM for the explicit time advance of the wavefield. We show numerically stable and high-resolution modeling and RTM results for the pure P-wave mode in VTI media. © 2012 Sinopec Geophysical Research Institute.
Rapid expansion and pseudo spectral implementation for reverse time migration in VTI media
Pestana, Reynam C
2012-04-24
In isotropic media, we use the scalar acoustic wave equation to perform reverse time migration (RTM) of the recorded pressure wavefield data. In anisotropic media, P- and SV-waves are coupled, and the elastic wave equation should be used for RTM. For computational efficiency, a pseudo-acoustic wave equation is often used. This may be solved using a coupled system of second-order partial differential equations. We solve these using a pseudo spectral method and the rapid expansion method (REM) for the explicit time marching. This method generates a degenerate SV-wave in addition to the P-wave arrivals of interest. To avoid this problem, the elastic wave equation for vertical transversely isotropic (VTI) media can be split into separate wave equations for P- and SV-waves. These separate wave equations are stable, and they can be effectively used to model and migrate seismic data in VTI media where |ε- δ| is small. The artifact for the SV-wave has also been removed. The independent pseudo-differential wave equations can be solved one for each mode using the pseudo spectral method for the spatial derivatives and the REM for the explicit time advance of the wavefield. We show numerically stable and high-resolution modeling and RTM results for the pure P-wave mode in VTI media. © 2012 Sinopec Geophysical Research Institute.
Effects of rapid maxillary expansion on head posture, postural stability, and fall risk
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Fatih Celebi
2017-01-01
Full Text Available Objective: The aim of this study was to investigate the effects of rapid maxillary expansion (RME on head posture, postural stability, and fall risk. Materials and Methods: A sample of 51 adolescent patients was randomly divided into two groups. In the first group, which consisted of 28 patients (15 females and 13 males, RME was performed as a part of routine orthodontic treatment. The remaining 23 individuals (12 females and 11 males served as the control group. Lateral cephalometric radiographs taken in natural head position, postural stability, and fall risk scores were obtained during the first visit. They were repeated on average 3.8 months and 3.5 months later for the study and control groups, respectively. The changes were analyzed using the Wilcoxon signed-rank test, paired samples t-test, Mann–Whitney U-test, and independent samples t-test. Results: As a result of RME, a statistically significant decrease was detected in the fall risk score (P < 0.05 in the study group, while the head position and postural stability remained unchanged. For the control group, no significant changes were observed in all measurements. Conclusions: The result of the present study suggests that RME has a capacity of improving fall risk.
Dahiya, Sagar; Chitra, Prasad; Rao, Sadam Srinivas; Bindra, Sukhvinder
2015-10-01
Transverse maxillary hypoplasia or maxillary constriction in conjunction with unilateral or bilateral posterior cross bites is a common finding in cleft palate patients. These situations are also commonly encountered in adults who have not had recourse to orthodontic treatment in childhood. In adults, after ossification of the mid palatal suture is complete, the accepted means of correcting transverse skeletal discrepancies is by Surgically Assisted Rapid Maxillary Expansion (SARME). The disadvantage of this technique in the Indian scenario is reduced patient acceptance and increased treatment costs. Le Fort-I down fracture and mid palatal suture sectioning requires hospitalization and increases morbidity. A case of a 21-year-old non-cleft male who presented with Class I malocclusion with transverse skeletal discrepancy and bilateral posterior cross bites is presented. A modified SAARME technique was performed without pterygomaxillary disjunction, as an outpatient procedure. The results obtained were satisfactory and the desired amount of transverse skeletal correction was achieved. The patient was discharged the same day. The technique can be used to successfully treat a large number of patients in India with maxillary skeletal transverse problems with increased predictability, reduced costs and morbidity and higher rates of acceptance.
Cevidanes, Lucia; Baccetti, Tiziano; Franchi, Lorenzo; McNamara, James A.; De Clerck, Hugo
2010-01-01
Objective To test the hypothesis that there is no difference in the active treatment effects for maxillary advancement induced by bone-anchored maxillary protraction (BAMP) and the active treatment effects for face mask in association with rapid maxillary expansion (RME/FM). Materials and Methods This is a study on consecutively treated patients. The changes in dentoskeletal cephalometric variables from start of treatment (T1) to end of active treatment (T2) with an average T1–T2 interval of about 1 year were contrasted in a BAMP sample of 21 subjects with a RME/FM sample of 34 patients. All subjects were prepubertal at T1. Statistical comparison was performed with t-tests for independent samples. Results The BAMP protocol produced significantly larger maxillary advancement than the RME/FM therapy (with a difference of 2 mm to 3 mm). Mandibular sagittal changes were similar, while vertical changes were better controlled with BAMP. The sagittal intermaxillary relationships improved 2.5 mm more in the BAMP patients. Additional favorable outcomes of BAMP treatment were the lack of clockwise rotation of the mandible as well as a lack of retroclination of the lower incisors. Conclusions The hypothesis is rejected. The BAMP protocol produced significantly larger maxillary advancement than the RME/FM therapy. PMID:20578848
Satilmis, Tulin; Ugurlu, Faysal; Garip, Hasan; Sener, Bedrettin C; Goker, Kamil
2011-06-01
To compare the effects of sedation and general anesthesia for surgically assisted rapid palatal expansion (SARPE). This randomized prospective study included 30 patients who were scheduled for SARPE, and was performed between January 2008 to February 2010 in the Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Marmara University, Istanbul, Turkey. Patients were allocated into Group S - midazolam + fentanyl sedation (n=15), and Group G - general anesthesia (n=15). Hemodynamic parameters, duration of anesthesia, surgery, recovery time, time to discharge, visual analogue scale (VAS) pain scores at 30 minutes (min), one hour (hr), 4 hours, 12 hours, and 24 hours, first consumption of analgesic time, total amount of consumption of analgesics, patient and surgeon satisfaction, nausea, and vomiting were recorded. Analgesic time was significantly longer in Group S (p=0.008), and total analgesic consumption was significantly lower in Group S than in Group G (p=0.031). Patient satisfaction was statistically higher in Group S (p=0.035). At 30 min, one hr, and 12 hrs, VAS satisfaction scores in Group S were statistically lower than those in Group G, and at 4 hrs and 24 hrs there was no statistical difference in VAS scores for both groups. The use of sedation for outpatient SARPE resulted in lower pain scores at discharge, lower analgesic consumption, and greater patient satisfaction.
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Larissa Carvalho Trojan Serpe
Full Text Available Introduction : This study aims to evaluate the influence of the biomechanical behavior of the midpalatal suture (MPS during the rapid maxillary expansion (RME when modeled by the Finite Element Method. Methods Four simulation alternatives are discussed and, for each analysis, the suture is considered as a functional unit with a different mechanical behavior: (i without MPS elements, (ii MPS with Young's modulus (E equal to 1 MPa, (ii MPS with E equal to 0.01 MPa and (iv MPS with bilinear elastic behavior. Results The stress analysis showed that, when MPS is not considered in the model, stress peaks are reduced in magnitude and their distribution is restricted to a smaller area when compared to the model with the inclusion of MPS (E=1 MPa. The increased suture stiffness also has a direct influence on MPS displacements after 30 expander activations. Conclusion The consideration of the MPS in RME computer models influences greatly the calculated displacements between the suture bone ends, even as the stress levels in maxillary structures. Furthermore, as proposed for the described model, the elastic bilinear behavior assigned to MPS allows coherent prediction of stresses and displacements results, being a good representation for this suture overall behavior.
Barbieri, Ana A; Scoralick, Raquel A; Naressi, Suely C M; Moraes, Mari E L; Daruge, Eduardo; Daruge, Eduardo
2013-01-01
The objective of this study was to demonstrate the effectiveness of rugoscopy as a human identification method, even when the patient is submitted to rapid palatal expansion, which in theory would introduce doubt. With this intent, the Rugoscopic Identity was obtained for each subject using the classification formula proposed by Santos based on the intra-oral casts made before and after treatment from patients who were subjected to palatal expansion. The casts were labeled with the patients' initials and randomly arranged for studying. The palatine rugae kept the same patterns in every case studied. The technical error of the intra-evaluator measurement provided a confidence interval of 95%, making rugoscopy a reliable identification method for patients who were submitted to rapid palatal expansion, because even in the presence of intra-oral changes owing to the use of palatal expanders, the palatine rugae retained the biological and technical requirements for the human identification process. © 2012 American Academy of Forensic Sciences.
Nada, R.M.; Fudalej, P.S.; Maal, T.J.J.; Berge, S.J.; Mostafa, Y.A.; Kuijpers-Jagtman, A.M.
2012-01-01
AIM: To three-dimensionally (3D) assess the long-term effects of tooth-borne and bone-borne surgically assisted rapid maxillary expansion (SARME). SUBJECTS AND METHODS: This prospective cohort study comprised 45 consecutive skeletally mature non-syndromic patients with transverse maxillary
LED phototherapy on midpalatal suture after rapid maxilla expansion: a Raman spectroscopic study
Rosa, Cristiane B.; Habib, Fernando Antonio L.; de Araújo, Telma M.; dos Santos, Jean N.; Cangussu, Maria Cristina T.; Barbosa, Artur Felipe S.; de Castro, Isabele Cardoso V.; Soares, Luiz Guilherme P.; Pinheiro, Antonio L. B.
2015-03-01
A quick bone formation after maxillary expansion would reduce treatment timeand the biomodulating effects of LED light could contribute for it. The aim of this study was to analyze the effect of LED phototherapy on the acceleration of bone formation at the midpalatal suture after maxilla expansion. Thirty rats divided into 6 groups were used on the study at 2 time points - 7 days: Control; Expansion; and Expansion + LED; and 14 days: Expansion; Expansion + LED in the first week; Expansion and LED in the first and second weeks. LED irradiation occurred at every 48 h during 2 weeks. Expansion was accomplished using a spatula and maintained with a triple helicoid of 0.020" stainless steel orthodontic wire. A LED light (λ850 ± 10nm, 150mW ± 10mW, spot of 0.5cm2, t=120 sec, SAEF of 18J/cm2) was applied in one point in the midpalatal suture immediately behind the upper incisors. Near infrared Raman spectroscopic analysis of the suture region was carried and data submitted to statistical analyzes (p≤0.05). Raman spectrum analysis demonstrated that irradiation increased hydroxyapatite in the midpalatal suture after expansion. The results of this indicate that LED irradiation; have a positive biomodulation contributing to the acceleration of bone formation in the midpalatal suture after expansion procedure.
Directory of Open Access Journals (Sweden)
Miller Paul
2012-12-01
Full Text Available Abstract Introduction To the best of our knowledge, this is the first report of a case of treatment-resistant depression in which the patient was evaluated for sleep disordered breathing as the cause and in which rapid palatal expansion to permanently treat the sleep disordered breathing produced a prolonged symptom-free period off medication. Case presentation An 18-year-old Caucasian man presented to our sleep disorders center with chronic severe depression that was no longer responsive to medication but that had recently responded to electroconvulsive therapy. Ancillary, persistent symptoms included mild insomnia, moderate to severe fatigue, mild sleepiness and severe anxiety treated with medication. Our patient had no history of snoring or witnessed apnea, but polysomnography was consistent with upper airway resistance syndrome. Although our patient did not have an orthodontic indication for rapid palatal expansion, rapid palatal expansion was performed as a treatment of his upper airway resistance syndrome. Following rapid palatal expansion, our patient experienced a marked improvement of his sleep quality, anxiety, fatigue and sleepiness. His improvement has been maintained off all psychotropic medication and his depression has remained in remission for approximately two years following his electroconvulsive therapy. Conclusions This case report introduces the possibility that unrecognized sleep disordered breathing may play a role in adolescent treatment-resistant depression. The symptoms of upper airway resistance syndrome are non-specific enough that every adolescent with depression, even those responding to medication, may have underlying sleep disordered breathing. In such patients, rapid palatal expansion, by widening the upper airway and improving airflow during sleep, may produce a prolonged improvement of symptoms and a tapering of medication. Psychiatrists treating adolescents may benefit from having another treatment option for
Johnson, Bret M; McNamara, James A; Bandeen, Roger L; Baccetti, Tiziano
2010-11-01
To evaluate changes in the soft tissue width of the nose induced by rapid maxillary expansion (RME). Data on greater alar cartilage (GAC) and alar base (AB) widths were compared with a normative sample within the same age range. This prospective study consisted of an RME sample of 79 patients treated with an RME protocol. Mean age at the start of RME treatment was 13.5 years; average duration of treatment was 6.7 months. Patients were grouped into prepubertal and postpubertal groups based on their cervical vertebral maturation (CVM) stage. AB and GAC widths were determined at three separate time points. The normative sample consisted of 437 orthodontically untreated whites, aged 10-16 years. A repeated measures analysis of variance (ANOVA) was used to determine group differences. In addition, independent sample t-tests were used to compare posttreatment nasal width values vs the untreated normative sample. Increases in AB and GAC widths of the nose in the RME sample were less than 1.5 mm. No significant differences were noted in width changes between the prepubertal and postpubertal subgroups. Comparisons of T3 values showed that on average nasal width increases were greater in the RME group than in untreated norms by 1.7 mm for the GAC measure (statistically significant), and by less than 1 mm for the AB measure. RME has no significant clinical effects on the widths of the apical base and the greater alar cartilage of the nose; no differences were observed between the two maturational subgroups.
Nada, R.M.; Loon, B. van; Schols, J.G.J.H.; Maal, T.J.J.; Koning, M.J.J. de; Mostafa, Y.A.; Kuijpers-Jagtman, A.M.
2013-01-01
This study aimed to assess the effects of bone-borne and tooth-borne surgically assisted rapid maxillary expansion on the volumes of the nose and nasal airway 2 yr after maxillary expansion. This prospective cohort study included 32 patients with transverse maxillary hypoplasia. Expansion was
Rapid replacement of bridge deck expansion joints study - phase I : [tech transfer summary].
2014-12-01
This initial research phase focused on documenting the current : means and methods of bridge expansion joint deterioration, : maintenance, and replacement and on identifying improvements : through all of the input gathered.
Lo Giudice, Antonino; Barbato, Ersilia; Cosentino, Leandro; Ferraro, Claudia Maria; Leonardi, Rosalia
2017-08-10
During rapid maxillary expansion (RME), heavy forces are transmitted to the maxilla by the anchored teeth causing buccal inclination and buccal bone loss of posterior teeth. To systematically review the literature in order to investigate whether RME causes periodontal sequelae, assessed by cone-beam computed tomography (CBCT). Fifteen electronic databases and reference lists of studies were searched up to March 2017. To be included in the systematic review, articles must be human studies on growing subjects, with transversal maxillary deficiency treated with RME and with assessment of buccal bone loss by CBCT images. Only randomized and non-randomized trials were included. Two authors independently performed study selection, data extraction, and risk of bias assessment. Study characteristics (study design, sample size, age, sex, skeletal maturity, type of appliance, daily activation, evaluated linear measurements, observation period, CBCT settings), and study outcomes (loss of buccal bone thickness and marginal bone) were reported according to the PRISMA statement. On the basis of the applied inclusion criteria, only six articles, three randomized clinical trials and three controlled clinical trials were included. An individual analysis of the selected articles was undertaken. The risks of bias of the six trials were scored as medium to low. The results of the present systematic review are based on a limited number of studies and only one study included a control group. In all considered studies, significant loss of buccal bone thickness and marginal bone level were observed in anchored teeth, following RME. Further prospective studies correlating the radiological data of bone loss to the periodontal soft tissues reaction after RME are required. A preliminary evaluation of the patient-related risk factors for RR may be advisable when considering to administering RME. This systematic review was registered in the National Institute of Health Research database with an
Directory of Open Access Journals (Sweden)
Juliana da S. Pereira
Full Text Available ABSTRACT OBJECTIVE: The aim of this randomized clinical trial was to evaluate the dental, dentoalveolar, and skeletal changes occurring right after the rapid maxillary expansion (RME and slow maxillary expansion (SME treatment using Haas-type expander. METHODS: All subjects performed cone-beam computed tomography (CBCT before installation of expanders (T1 and right after screw stabilization (T2. Patients who did not follow the research parameters were excluded. The final sample resulted in 21 patients in RME group (mean age of 8.43 years and 16 patients in SME group (mean age of 8.70 years. Based on the skewness and kurtosis statistics, the variables were judged to be normally distributed and paired t-test and student t-test were performed at significance level of 5%. RESULTS: Intermolar angle changed significantly due to treatment and RME showed greater buccal tipping than SME. RME showed significant changes in other four measurements due to treatment: maxilla moved forward and mandible showed backward rotation and, at transversal level both skeletal and dentoalveolar showed significant changes due to maxillary expansion. SME showed significant dentoalveolar changes due to maxillary expansion. CONCLUSIONS: Only intermolar angle showed significant difference between the two modalities of maxillary expansion with greater buccal tipping for RME. Also, RME produced skeletal maxillary expansion and SME did not. Both maxillary expansion modalities were efficient to promote transversal gain at dentoalveolar level. Sagittal and vertical measurements did not show differences between groups, but RME promoted a forward movement of the maxilla and backward rotation of the mandible.
DEFF Research Database (Denmark)
Nørgaard, Kristian Petersen; Dam-Johansen, Kim; Català, Pere
2013-01-01
, char properties, measured at room temperature, were dependent on the preceding storage conditions (in air or in a desiccator). The char was found to have the highest mechanical strength against compression in the outer crust facing the heat source. For thin (147μm) free coating films, a tendency...... with respect to the mechanical resistance against compression, degree of expansion, and residual mass fraction. Experimental results show that when using this type of shock heating, the mechanical resistance of the char against compression cannot meaningfully be correlated to the expansion factor. In addition...
Koudstaal, M.J.; Smeets, J.B.J.; Kleinrensink, G.J.; Schulten, A.J.M.; van der Wal, K.G.H.
2009-01-01
Purpose: This anatomic biomechanical study was undertaken to gain insight into the underlining mechanism of tipping of the maxillary segments during transverse expansion using tooth-borne and bone-borne distraction devices. Materials and Methods: An anatomic biomechanical study was performed on 10
Bilateral cross-bite treated by repeated rapid maxillary expansions: a 17-year follow-up case.
Cozzani, M; Mazzotta, L; Caprioglio, A
2014-07-01
The objective of this paper is to show the clinical results after the repeated application of a Haas expander for rapid maxillary expansion (RME) anchored onto deciduous teeth in a 7-year-old patient that presented bilateral cross-bite, superior crowding and no space for permanent lateral incisors eruption. A first Haas expander was applied to the patient. She was told to activate it once a day, each activation was equal to 0.20 mm. After the first RME, the bilateral cross-bite was solved but still there was not enough space for lateral incisor eruption. A second and then a third Haas expander were applied, with the same activation protocol as the first one, in order to gain space in the anterior region and to achieve proper eruption of the lateral incisors. The patient was then treated with fixed appliances. At debonding the patient presented well aligned arch-forms: space for lateral incisor eruption was gained and superior crowding was solved. Bilateral cross-bite was also corrected. She was seen again 10 years and 17 years after expansions: she showed no relapse and presented a good functional occlusion that had remained stable, and an aesthetically pleasant smile, however she exhibited gingival recessions. Repeated rapid maxillary expansion, anchored onto deciduous teeth, performed in early mixed dentition represents a safe and successful treatment to correct severe bilateral cross- bites and to create space for maxillary incisor eruption.
Wigner-Kirkwood expansion of the phase-space density for half infinite nuclear matter
International Nuclear Information System (INIS)
Durand, M.; Schuck, P.
1987-01-01
The phase space distribution of half infinite nuclear matter is expanded in a ℎ-series analogous to the low temperature expansion of the Fermi function. Besides the usual Wigner-Kirkwood expansion, oscillatory terms are derived. In the case of a Woods-Saxon potential, a smallness parameter is defined, which determines the convergence of the series and explains the very rapid convergence of the Wigner-Kirkwood expansion for average (nuclear) binding energies
Theoretical calculation of rapid x-ray transients and radius expansion
International Nuclear Information System (INIS)
Starrfield, S.; Sparks, W.; Truran, J.; Kenyon, S.
1984-01-01
We present the results of a calculation of a thermonuclear runaway on a 10 km neutron star which produced a precursor, radius expansion, and after the envelope had begun to shrink, a seconds x-ray burst about 2500 second later. Although such an event has not yet been observed, decreasing the initial envelope mass should bring the calculations into better agreement with the observations
Sadeghi, Arian; Ullenhag, Gustav; Wagenius, Gunnar; Tötterman, Thomas H; Eriksson, Fredrik
2013-06-01
Successful cell therapy relies on the identification and mass expansion of functional cells for infusion. Cryopreservation of cells is an inevitable step in most cell therapies which also entails consequences for the frozen cells. This study assessed the impact of cryopreservation and the widely used protocol for rapid expansion of T lymphocytes. The effects on cell viability, immunocompetence and the impact on apoptotic and immunosuppressive marker expression were analyzed using validated assays. Cryopreservation of lymphocytes during the rapid expansion protocol did not affect cell viability. Lymphocytes that underwent mass expansion or culture in high dose IL-2 were unable to respond to PHA stimulation by intracellular ATP production immediately after thawing (ATP = 16 ± 11 ng/ml). However, their reactivity to PHA was regained within 48 hours of recovery (ATP = 356 ± 61 ng/ml). Analysis of mRNA levels revealed downregulation of TGF-β and IL-10 at all time points. Culture in high dose IL-2 led to upregulation of p73 and BCL-2 mRNA levels while FoxP3 expression was elevated after culture in IL-2 and artificial TCR stimuli. FoxP3 levels decreased after short-term recovery without IL-2 or stimulation. Antigen specificity, as determined by IFNγ secretion, was unaffected by cryopreservation but was completely lost after addition of high dose IL-2 and artificial TCR stimuli. In conclusion, allowing short-time recovery of mass expanded and cryopreserved cells before reinfusion could enhance the outcome of adoptive cell therapy as the cells regain immune competence and specificity.
Spatial Linkage and Urban Expansion: AN Urban Agglomeration View
Jiao, L. M.; Tang, X.; Liu, X. P.
2017-09-01
Urban expansion displays different characteristics in each period. From the perspective of the urban agglomeration, studying the spatial and temporal characteristics of urban expansion plays an important role in understanding the complex relationship between urban expansion and network structure of urban agglomeration. We analyze urban expansion in the Yangtze River Delta Urban Agglomeration (YRD) through accessibility to and spatial interaction intensity from core cities as well as accessibility of road network. Results show that: (1) Correlation between urban expansion intensity and spatial indicators such as location and space syntax variables is remarkable and positive, while it decreases after rapid expansion. (2) Urban expansion velocity displays a positive correlation with spatial indicators mentioned above in the first (1980-1990) and second (1990-2000) period. However, it exhibits a negative relationship in the third period (2000-2010), i.e., cities located in the periphery of urban agglomeration developing more quickly. Consequently, the hypothesis of convergence of urban expansion in rapid expansion stage is put forward. (3) Results of Zipf's law and Gibrat's law show urban expansion in YRD displays a convergent trend in rapid expansion stage, small and medium-sized cities growing faster. This study shows that spatial linkage plays an important but evolving role in urban expansion within the urban agglomeration. In addition, it serves as a reference to the planning of Yangtze River Delta Urban Agglomeration and regulation of urban expansion of other urban agglomerations.
Directory of Open Access Journals (Sweden)
Zhao SY
2015-05-01
Full Text Available Shuya Zhao,1,* Xuxia Wang,2,* Na Li,3 Yun Chen,1 Yuran Su,1 Jun Zhang1 1Department of Orthodontics, 2Department of Oral and Maxillofacial Surgery, Faculty of Stomatology, Shandong University; 3Department of Orthodontics, Shandong Provincial Qianfoshan Hospital, Jinan, People’s Republic of China *These authors contributed equally to this work Background: The aim of this experimental study was to investigate the effects of strontium ranelate on bone regeneration in the mid-palatal suture in response to rapid maxillary expansion (RME.Methods: Thirty-six male 6-week-old Wistar rats were randomly divided into three groups, ie, an expansion only (EO group, an expansion plus strontium ranelate (SE group, and a control group. An orthodontic appliance was set between the right and left upper molars of rats with an initial expansive force of 0.98 N. Rats in the SE group were administered strontium ranelate (600 mg/kg body weight and then euthanized in batches on days 4, 7, and 10. Morphological changes in the mid-palatal suture were investigated using micro-computed tomography and hematoxylin and eosin staining after RME. Bone morphogenetic protein-2 expression in the suture was also examined to evaluate bone formation in the mid-palatal suture. Image-Pro Plus software was then used to determine the mean optical density of the immunohistochemical images. Analysis of variance was used for statistical evaluation at the P<0.05 level.Results: With expansive force, the mid-palatal suture was expanded, but there was no statistically significant difference (P>0.05 between the SE and EO groups. The bone volume of the suture decreased after RME, but was higher in the SE group than in the EO group on days 7 and 10. Further, expression of bone morphogenetic protein-2 in the SE group was higher than in the other two groups (P<0.05.Conclusion: Strontium ranelate may hasten new bone formation in the expanded mid-palatal suture, which may be therapeutically
Modified custom made J-hook for maxillary protraction in a rapid maxillary expansion appliance
Directory of Open Access Journals (Sweden)
Jithesh Kumar Kodoth
2014-01-01
Full Text Available A simple yet innovative attaching the J-hook along with an rapid maxillary appliance for the protraction of maxilla is presented. The proposed method not only simplifies construction but also is equally effective.
Directory of Open Access Journals (Sweden)
Rotem Gura Sadovsky
2017-03-01
Full Text Available The fluorescence microscopy methods presently used to characterize protein motion in cells infer protein motion from indirect observables, rather than measuring protein motion directly. Operationalizing these methods requires expertise that can constitute a barrier to their broad utilization. Here, we have developed PIPE (photo-converted intensity profile expansion to directly measure the motion of tagged proteins and quantify it using an effective diffusion coefficient. PIPE works by pulsing photo-convertible fluorescent proteins, generating a peaked fluorescence signal at the pulsed region, and analyzing the spatial expansion of the signal. We demonstrate PIPE’s success in measuring accurate diffusion coefficients in silico and in vitro and compare effective diffusion coefficients of native cellular proteins and free fluorophores in vivo. We apply PIPE to measure diffusion anomality in the cell and use it to distinguish free fluorophores from native cellular proteins. PIPE’s direct measurement and ease of use make it appealing for cell biologists.
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Namrata Dogra
2016-01-01
Full Text Available Aims and Objectives: To evaluate skeletal changes in maxilla and its surrounding structures, changes in the maxillary dentition and maxillary alveolar bone changes produced by bonded rapid maxillary expansion (RME using cone-beam computed tomography (CBCT. Materials and Methods: The sample consisted of 10 patients (6 males and 4 females with age range 12 to 15 years treated with bonded RME. CBCT scans were performed at T1 (pretreatment and at T2 (immediately after expansion to evaluate the dental, skeletal, and alveolar bone changes. Results: RME treatment increased the overall skeletal parameters such as interorbital, zygomatic, nasal, and maxillary widths. Significant increases in buccal maxillary width was observed at first premolar, second premolar, and first molar level. There was a significant increase in arch width both on the palatal side and on the buccal side. Significant tipping of right and left maxillary first molars was seen. There were significant reductions in buccal bone plate thickness and increase in palatal bone plate thickness. Conclusions: Total expansion achieved with RME was a combination of dental, skeletal and alveolar bone changes. At the first molar level, 28.45% orthopedic, 16.03% alveolar bone bending, and 55.5% orthodontic changes were observed.
Directory of Open Access Journals (Sweden)
Luca Levrini
2014-12-01
Full Text Available Rapid maxillary expansion (RME is a widely used practice in orthodontics. Scientific evidence shows that RME can be helpful in modifying the breathing pattern in mouth-breathing patients. In order to promote the restoration of physiological breathing we have developed a rehabilitation program associated with RME in children. The aim of the study was a literature review and a model of orofacial rehabilitation in children with obstructive sleep apnea undergoing treatment with rapid maxillary expansion. Muscular training (local exercises and general ones is the key factor of the program. It also includes hygienic and behavior instructions as well as other therapeutic procedures such as rhinosinusal washes, a postural re-education (Alexander technique and, if necessary, a pharmacological treatment aimed to improve nasal obstruction. The program should be customized for each patient. If RME is supported by an adequate functional rehabilitation, the possibility to change the breathing pattern is considerably amplified. Awareness, motivation and collaboration of the child and their parents, as well as the cooperation among specialists, such as orthodontist, speech therapist, pediatrician and otolaryngologist, are necessary conditions to achieve the goal.
Rana, Majeed; Gellrich, Nils-Claudius; Rana, Madiha; Piffkó, Jozsef; Kater, Wolfgang
2013-02-17
Ultrasonic bone-cutting surgery has been introduced as a feasible alternative to the conventional sharp instruments used in craniomaxillofacial surgery because of its precision and safety. The piezosurgery medical device allows the efficient cutting of mineralized tissues with minimal trauma to soft tissues. Piezoelectric osteotome has found its role in surgically assisted rapid maxillary expansion (SARME), a procedure well established to correct transverse maxillary discrepancies. The advantages include minimal risk to critical anatomic structures. The purpose of this clinical comparative study (CIS 2007-237-M) was to present the advantages of the piezoelectric cut as a minimally invasive device in surgically assisted, rapid maxillary expansion by protecting the maxillary sinus mucosal lining. Thirty patients (18 females and 12 males) at the age of 18 to 54 underwent a surgically assisted palatal expansion of the maxilla with a combined orthodontic and surgical approach. The patients were randomly divided into two separate treatment groups. While Group 1 received conventional surgery using an oscillating saw, Group 2 was treated with piezosurgery. The following parameters were examined: blood pressure, blood values, required medication, bleeding level in the maxillary sinus, duration of inpatient stay, duration of surgery and height of body temperature. The results displayed no statistically significant differences between the two groups regarding laboratory blood values and inpatient stay. The duration of surgery revealed a significant discrepancy. Deploying piezosurgery took the surgeon an average of 10 minutes longer than working with a conventional-saw technique. However, the observation of the bleeding level in the paranasal sinus presented a major and statistically significant advantage of piezosurgery: on average the bleeding level was one category above the one of the remaining patients. This method of piezoelectric surgery with all its advantages is going
Mutinelli, Sabrina; Manfredi, Mario; Guiducci, Antonio; Denotti, Gloria; Cozzani, Mauro
2015-01-01
Anchorage onto permanent dentition is a common procedure in rapid maxillary expansion. However, replacing first permanent molars with the second deciduous molars seems to be an option to reduce some negative side effects during orthodontic treatment. The purpose of this study was to evaluate the dental effect of rapid maxillary expansion with anchorage exclusively onto deciduous teeth performed in the first period of transition. Twenty patients with a lateral cross-bite treated exclusively by a Haas expander in early mixed dentition were retrospectively analyzed before treatment, at appliance removal, and at 21 months out of retention. The sagittal and transverse dimensions, together with the inter-canine arch and irregularity index, were digitally measured on scanned images of dental casts. The patients were compared with three balanced control groups (in total, 60 individuals) matched for gender. Two control groups had the same canine dental class as the treated group at T1, were in the inter-transitional period, and either had or lacked a lateral cross-bite. The last control group was comprised of adolescents in permanent dentition with a dental class I. The statistical analysis was performed by means of repeated-measures ANOVA for paired data and one-way ANOVA, the Kruskal-Wallis test, and the Mann-Whitney test for independent measures (α-level p dentition), the dental arch dimensions of treated patients were similar to those of adolescents with a dental class I and significantly wider than those of patients with a lateral cross-bite. Also, the anterior irregularity index was lower among patients who had undergone expansion treatments than in all untreated study participants. The Haas expander anchored to the deciduous teeth is effective in increasing the dental arch width in patients with a lateral cross-bite. The dimensions of the dental arch were modified earlier toward the values of the permanent dentition.
Thin-plate spline analysis of the short- and long-term effects of rapid maxillary expansion.
Franchi, Lorenzo; Baccetti, Tiziano; Cameron, Christopher G; Kutcipal, Elizabeth A; McNamara, James A
2002-04-01
The aim of this study was to investigate the short- and long-term effects induced by rapid maxillary expansion (RME) on the shape of the maxillary and circummaxillary structures by means of thin-plate spline (TPS) analysis. The sample consisted of 42 patients who were compared with a control sample of 20 subjects. The treated subjects underwent Haas-type RME, followed by fixed appliance therapy. Postero-anterior (PA) cephalograms were analysed for each treated subject at T1 (pre-treatment), T2 (immediate post-expansion), and T3 (long-term observation), and were available at T1 and T3 for the control group (CG). The mean age at T1 was 11 years and 10 months for both groups. The mean chronological ages at T3 were 20 years, 6 months for the treated group (TG) and 17 years, 8 months for the control group. The study focused on shape changes in the maxillary, nasal, zygomatic, and orbital regions. TPS analysis revealed significant shape changes in the TG. They consisted of an upward and lateral displacement of the two halves of the naso-maxillary complex as a result of active expansion in the short-term, and normalization of maxillary shape in the transverse dimension in the long-term (the initial transverse deficiency of the maxilla in the treated group was eliminated by RME therapy both in the short- and long-term). At the end of the observation period, the nasal cavities were larger when compared with both their pre-expansion configuration and the final configuration in the controls. RME with the Haas appliance appears to be an efficient therapeutic means to induce permanent favourable changes in the shape of the naso-maxillary complex.
Long vigil in Athabasca oil sands culminates in rapid expansion plans
Energy Technology Data Exchange (ETDEWEB)
1974-05-01
Great Canadian Oil Sands Ltd. needs to earn $40 million or more per year to get a reasonable return on the investment, vice president and general manager R.D. Humphreys told delegates at the Petroleum Accountants Society of W. Canada annual conference at Jasper Park Lodge. The conference then was ''the Alberta Oil Sands.'' Sun Oil Co. has taken no return yet, but has paid off the loans and taken shares in return so it owns nearly all the equity capital. The operation is not really breaking even at present, but should improve because GCOS is getting the full effect of the oil price increase under the original royalty agreement with the Alberta government. It is hoped that this will enable the company to recoup an accumulated deficit of more than $90 million. Money is the biggest problem for the current expansion designed to raise production to the authorized 65,000 bpd. Manpower is second and delivery of materials third. There is a lead time of 15 to 18 mo. on critical materials. Over the long term, tailings disposal is the greatest single problem facing all oil sands operators.
Müllers, Katrin C; Paisana, Maria; Wahl, Martin A
2015-02-01
We investigated the RESS process as a means of simultaneous micronization and cocrystallization of a model drug with poor aqueous solubility. 1:1 cocrystals of ibuprofen (IBU) and nicotinamide (NA) were produced with a pilot scale unit for RESS processing.IBU and NA were dissolved in scCO2 at 30 MPa and 50°C. After 24 h, the supercritical solution was expanded at a medium CO2 flow rate of 3.8 kg/h during 60 min into an expansion vessel kept at ambient conditions. Cocrystals were identified with DSC, XRD and confocal Raman microscopy (CRM) and further characterized by SEM, specific surface area, wetting ability, solubility and dissolution testing. Judging by DSC, XRD and CRM, cocrystals with high purity could be produced with the RESS technique. Micronization via RESS was successful, since the specific surface area of RESS cocrystals was increased almost tenfold in comparison to cocrystals produced by slow solvent evaporation. Due to the additional micronization, the mean dissolution time of IBU from RESS cocrystals was decreased. RESS cocrystallization offers the advantage of combining micronization and cocrystallization in a single production step. For drugs with dissolution-limited bioavailability, RESS cocrystallization may therefore be a superior approach in comparison to established cocrystallization techniques.
Fuchs, Jérôme; Johnson, Jeff A; Mindell, David P
2015-01-01
Understanding how and why lineages diversify is central to understanding the origins of biological diversity. The avian family Falconidae (caracaras, forest-falcons, falcons) has an uneven distribution of species among multiple well-supported clades, and provides a useful system for testing hypotheses about diversification rate and correlation with environmental changes. We analyzed eight independent loci for 1-7 individuals from each of the 64 currently recognized Falconidae species, together with two fossil falconid temporal calibrations, to assess phylogeny, absolute divergence times and potential shifts in diversification rate. Our analyses supported similar diversification ages in the Early to Middle Miocene for the three traditional subfamilies, Herpetotherinae, Polyborinae and Falconinae. We estimated that divergences within the subfamily Falconinae began about 16mya and divergences within the most species-rich genus, Falco, including about 60% of all Falconidae species, began about 7.5mya. We found evidence for a significant increase in diversification rate at the basal phylogenetic node for the genus Falco, and the timing for this rate shift correlates generally with expansion of C4 grasslands beginning around the Miocene/Pliocene transition. Concomitantly, Falco lineages that are distributed primarily in grassland or savannah habitats, as opposed to woodlands, and exhibit migratory, as opposed to sedentary, behavior experienced a higher diversification rate. Published by Elsevier Inc.
Wong, Terrence N; Miller, Christopher A; Klco, Jeffery M; Petti, Allegra; Demeter, Ryan; Helton, Nichole M; Li, Tiandao; Fulton, Robert S; Heath, Sharon E; Mardis, Elaine R; Westervelt, Peter; DiPersio, John F; Walter, Matthew J; Welch, John S; Graubert, Timothy A; Wilson, Richard K; Ley, Timothy J; Link, Daniel C
2016-02-18
There is interest in using leukemia-gene panels and next-generation sequencing to assess acute myelogenous leukemia (AML) response to induction chemotherapy. Studies have shown that patients with AML in morphologic remission may continue to have clonal hematopoiesis with populations closely related to the founding AML clone and that this confers an increased risk of relapse. However, it remains unknown how induction chemotherapy influences the clonal evolution of a patient's nonleukemic hematopoietic population. Here, we report that 5 of 15 patients with genetic clearance of their founding AML clone after induction chemotherapy had a concomitant expansion of a hematopoietic population unrelated to the initial AML. These populations frequently harbored somatic mutations in genes recurrently mutated in AML or myelodysplastic syndromes and were detectable at very low frequencies at the time of AML diagnosis. These results suggest that nonleukemic hematopoietic stem and progenitor cells, harboring specific aging-acquired mutations, may have a competitive fitness advantage after induction chemotherapy, expand, and persist long after the completion of chemotherapy. Although the clinical importance of these "rising" clones remains to be determined, it will be important to distinguish them from leukemia-related populations when assessing for molecular responses to induction chemotherapy. © 2016 by The American Society of Hematology.
Rapid expansion and fracture of metallic cylinders driven by explosive loads
International Nuclear Information System (INIS)
Hiroe, T.; Fujiwara, K.; Abe, T.; Yoshida, M.
2004-01-01
Smooth walled tubular specimens of stainless steel and low-carbon steels were explosively expanded to fragmentation. The driver was a column of the high explosive PETN inserted into the central bore and initiated by exploding a fine copper wire using a discharge current from a high-voltage capacitor bank. The variation of wall thickness and the effect of different explosive driver diameters are reported. A fully charged casing model was also exploded with initiation at the end surface for comparison. Streak and framing photos show both radially and axially symmetric expansion of cylinders at average strain rates of above 104 s-1 and a wall velocity of 417-1550 m/s. Some framing photos indicate the initiation and spacing of fractures during the bursting of the cylinders. Hydro codes have been applied to simulate the experimental behavior of the cylinders, examining numerical stresses, deformation and fracture criteria. Most of the fragments were successfully recovered inside a cushion-filled chamber, and the circumferential fracture spacing of measured fragments is investigated using a fragmentation model
DEFF Research Database (Denmark)
Zhao, Wenjun; Zhu, Xiaodong; Reenberg, Anette
2010-01-01
Beginning in 2000, Lianyungang's urbanization entered a period of rapid growth, spatially as well as economically. Rapid and intensive expansion of "construction land" imposed increasing pressures on regional environment. With the support of remote sensing data and GIS tools, this paper reports a...
Reaction of the nasal septal cartilage to rapid expansion of the maxillary dental arch
International Nuclear Information System (INIS)
Horisaka, Takashi
1981-01-01
1) In the control group, in which maxillary expansion was not performed, the cell proliferation and uptake of [ 3 H] proline in the septal cartilage were found to be more remarkable at the area of the septoethmoidal junction than other areas of the cartilage. In the experimental group, however, higher activity of the cell proliferation and more intense uptake of [ 3 H] proline were found at the area adjacent to the septoethmoidal junction than the control, while no change was observed in other areas of the septal cartilage. 2) The cartilaginous cells at the septoethmoidal junction represented the columnar pattern in their alignment and the cells were classified into five zones according to their morphological characteristics, i.e. resting, proliferative, transitional, hypertrophic and erosion zones. 3) Distribution of the labeled nuclei with [methyl- 3 H] thymidine was confined almost to the proliferative and transitional zones. In these two zones, the cell proliferation indicated by labeling index increased about 50% in the experimental group as compared with the control. 4) Uptake of [ 3 H] proline was the highest in the transitional zone followed by the proliferative zone. Uptake of [ 3 H] proline indicated by grain counts/2000 μm 2 increased about 50% in the transitional zone and about 30% in the proliferative zone respectively in the experimental group as compared with control. 5) The septo-premaxillary ligament named by Latham (1970) was found also in rats to arise from the perichondrium of antero-inferior portion of the nasal septum, to course postero-inferiorly and to insert into the anterior portion of the premaxillary bones. Uptake of [ 3 H] proline indicated by grain counts/400 μm 2 increased about 30% in the area of insertion of the ligament in the experimental group as compared with the control. (J.P.N.)
Gaveau, David L. A.; Sheil, Douglas; Husnayaen; Salim, Mohammad A.; Arjasakusuma, Sanjiwana; Ancrenaz, Marc; Pacheco, Pablo; Meijaard, Erik
2016-09-01
New plantations can either cause deforestation by replacing natural forests or avoid this by using previously cleared areas. The extent of these two situations is contested in tropical biodiversity hotspots where objective data are limited. Here, we explore delays between deforestation and the establishment of industrial tree plantations on Borneo using satellite imagery. Between 1973 and 2015 an estimated 18.7 Mha of Borneo’s old-growth forest were cleared (14.4 Mha and 4.2 Mha in Indonesian and Malaysian Borneo). Industrial plantations expanded by 9.1 Mha (7.8 Mha oil-palm; 1.3 Mha pulpwood). Approximately 7.0 Mha of the total plantation area in 2015 (9.2 Mha) were old-growth forest in 1973, of which 4.5-4.8 Mha (24-26% of Borneo-wide deforestation) were planted within five years of forest clearance (3.7-3.9 Mha oil-palm; 0.8-0.9 Mha pulpwood). This rapid within-five-year conversion has been greater in Malaysia than in Indonesia (57-60% versus 15-16%). In Indonesia, a higher proportion of oil-palm plantations was developed on already cleared degraded lands (a legacy of recurrent forest fires). However, rapid conversion of Indonesian forests to industrial plantations has increased steeply since 2005. We conclude that plantation industries have been the principle driver of deforestation in Malaysian Borneo over the last four decades. In contrast, their role in deforestation in Indonesian Borneo was less marked, but has been growing recently. We note caveats in interpreting these results and highlight the need for greater accountability in plantation development.
Gaveau, David L A; Sheil, Douglas; Husnayaen; Salim, Mohammad A; Arjasakusuma, Sanjiwana; Ancrenaz, Marc; Pacheco, Pablo; Meijaard, Erik
2016-09-08
New plantations can either cause deforestation by replacing natural forests or avoid this by using previously cleared areas. The extent of these two situations is contested in tropical biodiversity hotspots where objective data are limited. Here, we explore delays between deforestation and the establishment of industrial tree plantations on Borneo using satellite imagery. Between 1973 and 2015 an estimated 18.7 Mha of Borneo's old-growth forest were cleared (14.4 Mha and 4.2 Mha in Indonesian and Malaysian Borneo). Industrial plantations expanded by 9.1 Mha (7.8 Mha oil-palm; 1.3 Mha pulpwood). Approximately 7.0 Mha of the total plantation area in 2015 (9.2 Mha) were old-growth forest in 1973, of which 4.5-4.8 Mha (24-26% of Borneo-wide deforestation) were planted within five years of forest clearance (3.7-3.9 Mha oil-palm; 0.8-0.9 Mha pulpwood). This rapid within-five-year conversion has been greater in Malaysia than in Indonesia (57-60% versus 15-16%). In Indonesia, a higher proportion of oil-palm plantations was developed on already cleared degraded lands (a legacy of recurrent forest fires). However, rapid conversion of Indonesian forests to industrial plantations has increased steeply since 2005. We conclude that plantation industries have been the principle driver of deforestation in Malaysian Borneo over the last four decades. In contrast, their role in deforestation in Indonesian Borneo was less marked, but has been growing recently. We note caveats in interpreting these results and highlight the need for greater accountability in plantation development.
Li, Xiangdong; Zhu, Tiansheng; Yin, Xiao; Zhang, Chengling; Chen, Jia; Tian, Yanping; Liu, Jinliang
2017-08-29
Turnip mosaic virus (TuMV) is one of the most widespread and economically important virus infecting both crop and ornamental species of the family Brassicaceae. TuMV isolates can be classified to five phylogenetic lineages, basal-B, basal-BR, Asian-BR, world-B and Orchis. To understand the genetic structure of TuMV from radish in China, the 3'-terminal genome of 90 TuMV isolates were determined and analyzed with other available Chinese isolates. The results showed that the Chinese TuMV isolates from radish formed three groups: Asian-BR, basal-BR and world-B. More than half of these isolates (52.54%) were clustered to basal-BR group, and could be further divided into three sub-groups. The TuMV basal-BR isolates in the sub-groups I and II were genetically homologous with Japanese ones, while those in sub-group III formed a distinct lineage. Sub-populations of TuMV basal-BR II and III were new emergent and in a state of expansion. The Chinese TuMV radish populations were under negative selection. Gene flow between TuMV populations from Tai'an, Weifang and Changchun was frequent. The genetic structure of Turnip mosaic virus population reveals the rapid expansion of a new emergent lineage in China.
Directory of Open Access Journals (Sweden)
Alessandro Ugolini
2016-01-01
Full Text Available Abstract Background The purpose of this controlled study was to investigate indirect effects on mandibular arch dimensions, 1 year after rapid palatal expansion (RPE therapy. Methods Thirty-three patients in mixed dentition (mean age 8.8 years showing unilateral posterior crossbite and maxillary deficiency were treated with a RPE (Haas type cemented on the first permanent molars. Treatment protocol consisted of two turns per day until slight overcorrection of the molar transverse relationship occurred. The Haas expander was kept on the teeth as a passive retainer for an average of 6 months. Study models were taken prior (T1 and 15 months on average (T2 after expansion. A control group of 15 untreated subjects with maxillary deficiency (mean age 8.3 years was also recorded with a 12-month interval. Stone casts were digitized with a 3D scanner (3Shape, DK. Results In the treated group, both mandibular intermolar distance (+1.9 mm and mandibular molar angulation (+9° increased. Mandibular incisor angulation showed an increase of 1.9°. There was little effect on intercanine distance and canine angulation. Controls showed a reduction in transverse arch dimension and a decrease in molar and canine angulation values. Conclusions RPE protocol has indirect widening effects on the mandibular incisors and first molars.
International Nuclear Information System (INIS)
Bakhshan, Y.; Karim, G. A.; Mansouri, S. H.
2003-01-01
In this investigation, the instantaneous unsteady heat transfer within a pneumatically driven rapid compression-expansion machine that offers simple, well-controlled and known boundary conditions was studied. Values of the instantaneous apparent overall heat flux from the cylinder gas to the wall surfaces were calculated using a thermodynamics analysis of the experimentally measured pressure and volume temporal development. Corresponding heat flux values were also calculated through the application of a zero-dimensional k- ε turbulence model the characteristic velocity is a contribution of turbulence kinetic energy, mean kinetic energy of charged air into cylinder and piston motion for the calculation of Reynolds, Nusselt and Prandtl numbers. Comparison of the zero-dimensional k- ε turbulence model prediction with experimental data shows good agreement for all compression ratios
Directory of Open Access Journals (Sweden)
Arthur César de Medeiros Alves
Full Text Available ABSTRACT Objective: The aim of this systematic review was to analyze the short and long-term spontaneous dentoalveolar changes of the mandibular dental arch after slow (SME or rapid (RME maxillary expansion in the mixed and early permanent dentitions. Methods: An electronic search was performed in the following databases: PubMed/Medline, Cochrane Library, Scopus, Embase and Web of Science. Eligibility criteria for article selection included randomized controlled trials and prospective studies written in English, with no restriction of year of publication, involving patients who underwent SME or RME during the mixed or early permanent dentitions. A double-blind search of articles was performed by two reviewers. Initially, the title and the abstract of the studies were read, and their references were also hand-searched for possible missing studies. A methodological quality scoring scale was used to analyze the selected articles. Results: The search retrieved 373 articles, but only 6 were selected for review after application of the eligibility and exclusion criteria. Non-clinically significant spontaneous dentoalveolar changes of approximately 1mm were found in the mandibular dental arch in the short and long-term, after slow or rapid maxillary expansions. Furthermore, no significant differences were found between treated and control groups. Conclusions: There is enough evidence to conclude that negligible short and long-term spontaneous dentoalveolar changes tend to occur in the mandibular dental arch after SME or RME in the mixed and early permanent dentitions. More randomized studies with appropriate control group are required to better evaluate this issue.
Directory of Open Access Journals (Sweden)
Maria Olívia Rocha
Full Text Available ABSTRACT Objective: To assess, during rapid maxillary expansion, the plaque index (PI and the gingival index (GI of patients with unilateral cleft lip and palate(UCLP using Hyrax (HX or inverted mini-Hyrax (IMHX rapid maxillary expanders (RME considering patients’ sex and age. Methods: PI (Quigley Index modified by Turesky et al and GI (Löe and Silness of 28 UCLP (11 females; 17 males: aged 8 to 15 years submitted to daily RME activation were assessed before (T0 and 7 (T1, 28 (T2 and 90 (T3 days after activation. Log-linear models and Bonferroni correction were performed to analyze possible differences in PI and GI between RME, sexes or age groups over time. Results: Intra-group comparison revealed significant increases in PI of patients using HX (T0 < T2, IMHX (T0 < T3; T1< T3, males (T0 < T1; T0 < T2; T0 < T3 or aged 12-15 years (T0 < T1; T0 < T2; T0 < T3, and in GI of patients using IMHX (T0 < T3; T1 < T3, females (T1 < T3; T2 < T3 or aged 12-15 years (T0 < T3; T2 < T3. One inter-group difference in GI according to patients’ age (8-11 < 12-15; T1 was observed. Conclusions: Since a single difference between groups was encountered, the results of this study indicated that PI and GI during maxillary expansion were similar between HX and IMHX, sexes and the analyzed age groups. Therefore, orthodontists can use these RME in UCLP patients according to the patient’s necessity or their preferences.
Matsuyama, K; Mishima, K; Umemoto, H; Yamaguchi, S
2001-10-15
A novel method is reported for forming polymer microparticles, which reduce atmospheric emissions of environmentally harmful volatile organic compounds such as toluene and xylene used as paint solvent in paint industry. The polymer microparticles have formed through rapid expansion from supercritical solution with a nonsolvent (RESS-N). Solubilization of poly(styrene)-b-(poly(methyl methacrylate)-co-poly (glycidyl methacrylate)) copolymer(PS-b-(PMMA-co-PGMA), MW = 5000, PS/PMMA/PGMA = 2/5/3), poly(ethylene glycol) (PEG, M. W = 4000), bisphenol A type epoxy resin (EP, MW = 3000), poly(methyl methacrylate) (PMMA; MW = 15000, 75000, 120000), and poly(oxyalkylene) alkylphenyl ether (MW = 4000) in carbon dioxide (CO2) was achieved with the use of small alcohols as cosolvents. The solubility of the PS-b-(PMMA-co-PGMA) is extremely low in either CO2 or ethanol but becomes 20 wt % in a mixture of the two. Because ethanol is a nonsolvent for the polymer, it can be used as a cosolvent in rapid expansion from supercritical solution to produce 1-3 microm particles that do not agglomerate. Obtained polymer particles by RESS-N were applied as powder coatings. The resulting coatings have a smooth and coherent film. The particle size distribution of microspheres was controlled by changing the polymer concentration, preexpansion pressure, temperature, and injection distance. The feed compositions were more effective than the other factors in controlling the particle size. The polymeric microparticles formed by RESS-N method can be utilized to make the thin coating film without anytoxic organic solvents and/or surfactants.
Ma, Ning; Szilagyi, Jozsef; Niu, Guo-Yue; Zhang, Yinsheng; Zhang, Teng; Wang, Binbin; Wu, Yanhong
2016-06-01
Previous studies have shown that the majority of the lakes in the Tibetan Plateau (TP) started to expand rapidly since the late 1990s. However, the causes are still not well known. For Nam Co, being a closed lake with no outflow, evaporation (EL) over the lake surface is the only way water may leave the lake. Therefore, quantifying EL is key for investigating the mechanism of lake expansion in the TP. EL can be quantified by Penman- and/or bulk-transfer-type models, requiring only net radiation, temperature, humidity and wind speed for inputs. However, interpolation of wind speed data may be laden with great uncertainty due to extremely sparse ground meteorological observations, the highly heterogeneous landscape and lake-land breeze effects. Here, evaporation of Nam Co Lake was investigated within the 1979-2012 period at a monthly time-scale using the complementary relationship lake evaporation (CRLE) model which does not require wind speed data. Validations by in-situ observations of E601B pan evaporation rates at the shore of Nam Co Lake as well as measured EL over an adjacent small lake using eddy covariance technique suggest that CRLE is capable of simulating EL well since it implicitly considers wind effects on evaporation via its vapor transfer coefficient. The multi-year average of annual evaporation of Nam Co Lake is 635 mm. From 1979 to 2012, annual evaporation of Nam Co Lake expressed a very slight decreasing trend. However, a more significant decrease in EL occurred during 1998-2008 at a rate of -12 mm yr-1. Based on water-level readings, this significant decrease in lake evaporation was found to be responsible for approximately 4% of the reported rapid water level increase and areal expansion of Nam Co Lake during the same period.
Directory of Open Access Journals (Sweden)
Rogério Christofoletti
2008-12-01
Full Text Available Three ideas would suffice for the reading of “Cultura da Convergência” (Culture of Convergence by Henry Jenkins to be of interest to journalists and researchers in the area: media convergence as a cultural process; the strengthening of an emotional economy which guides consumers of symbolic goods and media creators; the expansion of trans-media narrative forms.
Directory of Open Access Journals (Sweden)
Rogério Christofoletti
2011-02-01
Full Text Available Three ideas would suffice for the reading of “Cultura da Convergência” (Culture of Convergence by Henry Jenkins to be of interest to journalists and researchers in the area: media convergence as a cultural process; the strengthening of an emotional economy which guides consumers of symbolic goods and media creators; the expansion of trans-media narrative forms.
Chemical graph-theoretic cluster expansions
International Nuclear Information System (INIS)
Klein, D.J.
1986-01-01
A general computationally amenable chemico-graph-theoretic cluster expansion method is suggested as a paradigm for incorporation of chemical structure concepts in a systematic manner. The cluster expansion approach is presented in a formalism general enough to cover a variety of empirical, semiempirical, and even ab initio applications. Formally such approaches for the utilization of chemical structure-related concepts may be viewed as discrete analogues of Taylor series expansions. The efficacy of the chemical structure concepts then is simply bound up in the rate of convergence of the cluster expansions. In many empirical applications, e.g., boiling points, chromatographic separation coefficients, and biological activities, this rate of convergence has been observed to be quite rapid. More note will be made here of quantum chemical applications. Relations to questions concerning size extensivity of energies and size consistency of wave functions are addressed
Energy Technology Data Exchange (ETDEWEB)
Cho, Gyubaek; Jeong, Dongsoo [Engine Research Team, Eco-Machinery Research Division, Korea Institute of Machinery and Materials, 104 Sinseongno, Yuseong-gu, Daejeon 305-701 (Korea); Moon, Gunfeel [Department of Clean Environmental system, University of Science and Technology, 52 Eoeun-dong, Yuseong-gu, Daejeon (Korea); Bae, Choongsik [Engine Laboratory, Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, 373-1 GuSeong-Dong, Yuseong-Gu, Daejeon 305-701 (Korea)
2010-10-15
The characteristics of controlled auto-ignition (CAI) were investigated with a methane-air mixture and simulated residual gas, that represents internal exhaust gas recirculation (IEGR). Supply systems were additionally installed on the conventional rapid compression machine (RCM), and this modified machine - a rapid intake compression and expansion machine (RICEM) - was able to simulate an intake stroke for the evaluation of controlled auto-ignition with fuel-air mixture. The fuel-air mixture and the simulated residual gas were introduced separately into the combustion chamber through the spool valves. Various IEGR rates and temperatures of the IEGR gas were tested. The initial reaction and the development in controlled auto-ignition combustion were compared with spark-ignited combustion by visualization with a high-speed digital camera. Under the controlled auto-ignition operation, multi-point ignition and faster combustion were observed. With increasing the temperature of IEGR gas, the auto-ignition timing was advanced and burning duration was shortened. The higher rate of IEGR had the same effects on the combustion of the controlled auto-ignition. However, this trend was reversed with more than 47 per cent of IEGR. (author)
McNamara, James A; Sigler, Lauren M; Franchi, Lorenzo; Guest, Susan S; Baccetti, Tiziano
2010-03-01
To prospectively measure occlusal changes in mixed dentition patients who underwent a standardized early expansion protocol. The treatment sample consisted of 500 patients who were assigned to three groups according to molar relationship: Class I (n = 204), end-to-end (n = 166), and Class II (n = 130). All patients were treated with a bonded rapid maxillary expander (RME) followed by a removable maintenance plate and a transpalatal arch. Mean age at the start of treatment was 8.8 years (T(1)), with a pre-phase 2 treatment cephalogram (T(2)) taken 3.7 years later. The control sample consisted of the cephalometric records of 188 untreated subjects (Class 1, n = 79; end-to-end, n = 51; Class II, n = 58). The largest change in molar relationship was noted when the Class II treatment group (1.8 mm) was compared with the matched control group (0.3 mm). A positive change was seen in 81% of the Class II treatment group, with almost half of the group improving by > or = 2.0 mm. The end-to-end treatment group had a positive change of 1.4 mm, compared with a control value of 0.6 mm, and the Class I group of about 1 mm compared with controls, who remained unchanged (0.1 mm). Skeletal changes were not significant when any of the groups were compared with controls. The expansion protocol had a significantly favorable effect on the sagittal occlusal relationships of Class II, end-to-end, and Class I patients treated in the early mixed dentition.
MacGinnis, Matt; Chu, Howard; Youssef, George; Wu, Kimberley W; Machado, Andre Wilson; Moon, Won
2014-08-29
Orthodontic palatal expansion appliances have been widely used with satisfactory and, most often, predictable clinical results. Recently, clinicians have successfully utilized micro-implants with palatal expander designs to work as anchors to the palate to achieve more efficient skeletal expansion and to decrease undesired dental effects. The purpose of the study was to use finite element method (FEM) to determine the stress distribution and displacement within the craniofacial complex when simulated conventional and micro-implant-assisted rapid palatal expansion (MARPE) expansion forces are applied to the maxilla. The simulated stress distribution produced within the palate and maxillary buttresses in addition to the displacement and rotation of the maxilla could then be analyzed to determine if micro-implants aid in skeletal expansion. A three-dimensional (3D) mesh model of the cranium with associated maxillary sutures was developed using computed tomography (CT) images and Mimics modeling software. To compare transverse expansion stresses in rapid palatal expansion (RPE) and MARPE, expansion forces were distributed to differing points on the maxilla and evaluated with ANSYS simulation software. The stresses distributed from forces applied to the maxillary teeth are distributed mainly along the trajectories of the three maxillary buttresses. In comparison, the MARPE showed tension and compression directed to the palate, while showing less rotation, and tipping of the maxillary complex. In addition, the conventional hyrax displayed a rotation of the maxilla around the teeth as opposed to the midpalatal suture of the MARPE. This data suggests that the MARPE causes the maxilla to bend laterally, while preventing unwanted rotation of the complex. In conclusion, the MARPE may be beneficial for hyperdivergent patients, or those that have already experienced closure of the midpalatal suture, who require palatal expansion and would worsen from buccal tipping of the teeth
Zhao, Wenjun; Zhu, Xiaodong; Reenberg, Anette; Sun, Xiang
2010-10-01
Beginning in 2000, Lianyungang's urbanization entered a period of rapid growth, spatially as well as economically. Rapid and intensive expansion of "construction land" imposed increasing pressures on regional environment. With the support of remote sensing data and GIS tools, this paper reports a "present-capacity-potential" integrated suitability analysis framework, in order to characterize and evaluate the suitability of urban expansion in Lianyungang. We found that during the rapid coastal urbanization process from 2000 to 2008, the characteristics of physical expansion in the study area were characterized by a combination of high-density expansion and sprawling development. The land use conversion driven by urbanization and industrialization has not occurred only in city districts, but also the surrounding areas that were spatially absorbed by urban growth, while closely associated and greatly influenced by the explosive growth of industrial establishment. The over-consumption of land resources in the areas with low environmental carrying capacity, particularly in the eastern coastal area, should be strictly controlled. Compared to conventional land suitability analysis methods, the proposed integrated approach could better review the potential environmental impacts of urban expansion and provide guidance for decision makers.
Krishnan, Sundar Rajan; Srinivasan, Kalyan Kumar; Stegmeir, Matthew
2015-11-01
Direct-injection compression ignition combustion of diesel and gasoline were studied in a rapid compression-expansion machine (RCEM) using high-speed OH* chemiluminescence imaging. The RCEM (bore = 84 mm, stroke = 110-250 mm) was used to simulate engine-like operating conditions at the start of fuel injection. The fuels were supplied by a high-pressure fuel cart with an air-over-fuel pressure amplification system capable of providing fuel injection pressures up to 2000 bar. A production diesel fuel injector was modified to provide a single fuel spray for both diesel and gasoline operation. Time-resolved combustion pressure in the RCEM was measured using a Kistler piezoelectric pressure transducer mounted on the cylinder head and the instantaneous piston displacement was measured using an inductive linear displacement sensor (0.05 mm resolution). Time-resolved, line-of-sight OH* chemiluminescence images were obtained using a Phantom V611 CMOS camera (20.9 kHz @ 512 x 512 pixel resolution, ~ 48 μs time resolution) coupled with a short wave pass filter (cut-off ~ 348 nm). The instantaneous OH* distributions, which indicate high temperature flame regions within the combustion chamber, were used to discern the characteristic differences between diesel and gasoline compression ignition combustion. The authors gratefully acknowledge facilities support for the present work from the Energy Institute at Mississippi State University.
Directory of Open Access Journals (Sweden)
Daniele Nóbrega Nardoni
2015-02-01
Full Text Available INTRODUCTION: Prognosis is the main limitation of interceptive treatment of Class III malocclusions. The interceptive procedures of rapid maxillary expansion (RME and face mask therapy performed in early mixed dentition are capable of achieving immediate overcorrection and maintenance of facial and occlusal morphology for a few years. Individuals presenting minimal acceptable faces at growth completion are potential candidates for compensatory orthodontic treatment, while those with facial involvement should be submitted to orthodontic decompensation for orthognathic surgery. OBJECTIVES: To investigate cephalometric variables that might predict the outcomes of orthopedic treatment with RME and face mask therapy (FM. METHODS: Cephalometric analysis of 26 Class III patients (mean age of 8 years and 4 months was performed at treatment onset and after a mean period of 6 years and 10 months at pubertal growth completion, including a subjective facial analysis. Patients was divided into two groups: success group (21 individuals and failure group (5 individuals. Discriminant analysis was applied to the cephalometric values at treatment onset. Two predictor variables were found by stepwise procedure. RESULTS: Orthopedic treatment of Class III malocclusion may have unfavorable prognosis at growth completion whenever initial cephalometric analysis reveals increased lower anterior facial height (LAFH combined with reduced angle between the condylar axis and the mandibular plane (CondAx.MP. CONCLUSION: The results of treatment with RME and face mask therapy at growth completion in Class III patients could be predicted with a probability of 88.5%.
Directory of Open Access Journals (Sweden)
Carolina da Luz Baratieri
2014-10-01
Full Text Available The aim of this study was to assess by means of cone-beam computed tomography (CBCT scans the transverse effects on the nasomaxillary complex in patients submitted to rapid maxillary expansion (RME using Haas expander in comparison to untreated individuals. This prospective controlled clinical study assessed 30 subjects (18 boys and 12 girls with mixed dentition and during pubertal growth. The treated group was submitted to RME with Haas expander, retention for six months and a six-month follow-up after removal. The control group matched the treated group in terms of age and sex distribution. CBCT scans were taken at treatment onset and one year after the expander was activated. Maxillary first molars (U6 width, right and left U6 angulation, maxillary alveolar width, maxillary basal width, palatal alveolar width, palatal base width, right and left alveolar angulation, palatal area, nasal base width, nasal cavity width and inferior nasal cavity area on the posterior, middle and anterior coronal slices were measured with Dolphin Imaging Software(r 11.5, except for the first two variables which were performed only on the posterior slice. All transverse dimensions increased significantly (P 0.05. Results suggest that increase of molar, maxillary, palatal and nasal transverse dimensions was stable in comparison to the control group one year after treatment with RME.
Kılıç, Nihat; Yörük, Özgür; Kılıç, Songül Cömert; Çatal, Gülhan; Kurt, Sezgin
2016-09-01
To test the null hypothesis that there are significant differences in hearing improvements of children with resistance otitis media with effusion (OME) who undergo a rapid maxillary expansion (RME) procedure or ventilation tube placement. Forty-two children between 4.5 and 15 years old were divided into three groups: RME, ventilation tube, and control groups. The RME group consisted of 15 children with maxillary constriction and resistance OME that indicated ventilation tube placement. The ventilation tube group consisted of 16 children for whom ventilation tube placement was indicated but no maxillary constriction. The control group consisted of 11 children with no orthodontic and/or rhinologic problems. Hearing thresholds were evaluated with three audiometric records: (1) before RME/ventilation tube placement (T0); (2) after RME/ventilation tube placement (T1), and (3) after an observation period of 10 months (T2). The control group was matched to these periods, except T1. Hearing thresholds decreased significantly in both the RME and ventilation tube groups (P .05). Slight changes were observed in the control groups. The null hypothesis was rejected. RME showed similar effects as ventilation tube placement for release of otitis media and improvement of hearing thresholds levels. RME should be preferred as a first treatment option for children with maxillary constriction and resistance OME.
Nicaise, Samuel M.; Gadelrab, Karim R.; G, Amir Tavakkoli K.; Ross, Caroline A.; Alexander-Katz, Alfredo; Berggren, Karl K.
2018-01-01
Directed self-assembly of block copolymers (BCPs) provided by shear-stress can produce aligned sub-10 nm structures over large areas for applications in integrated circuits, next-generation data storage, and plasmonic structures. In this work, we present a fast, versatile BCP shear-alignment process based on coefficient of thermal expansion mismatch of the BCP film, a rigid top coat and a substrate. Monolayer and bilayer cylindrical microdomains of poly(styrene-b-dimethylsiloxane) aligned preferentially in-plane and orthogonal to naturally-forming or engineered cracks in the top coat film, allowing for orientation control over 1 cm2 substrates. Annealing temperatures, up to 275 °C, provided low-defect alignment up to 2 mm away from cracks for rapid (<1 min) annealing times. Finite-element simulations of the stress as a function of annealing time, annealing temperature, and distance from cracks showed that shear stress during the cooling phase of the thermal annealing was critical for the observed microdomain alignment.
Baccetti, Tiziano; Franchi, Lorenzo; McNamara, James A
2004-07-01
The aim of this study was to select a model of cephalometric variables to predict the results of early treatment of Class III malocclusion with rapid maxillary expansion and facemask therapy followed by comprehensive treatment with fixed appliances. Lateral cephalograms of 42 patients (20 boys, 22 girls) with Class III malocclusion were analyzed at the start of treatment (mean age 8 years 6 months +/- 2 years, at stage I in cervical vertebral maturation). All patients were reevaluated after a mean period of 6 years 6 months (at stage IV or V in cervical vertebral maturation) that included active treatment plus retention. At this time, the sample was divided into 2 groups according to occlusal criteria: a successful group (30 patients) and an unsuccessful group (12 patients). Discriminant analysis was applied to select pretreatment predictive variables of long-term treatment outcome. Stepwise variable selection of the cephalometric measurements at the first observation identified 3 predictive variables. Orthopedic treatment of Class III malocclusion might be unfavorable over the long term when a patient's pretreatment cephalometric records exhibit a long mandibular ramus (ie, increased posterior facial height), an acute cranial base angle, and a steep mandibular plane angle. On the basis of the equation generated by the multivariate statistical method, the outcome of interceptive orthopedic treatment for each new patient with Class III malocclusion can be predicted with a probability error of 16.7%.
Directory of Open Access Journals (Sweden)
Ashok Surana
2012-01-01
Full Text Available This case report describes the management of skeletal Class III malocclusion with maxillary deficiency in an adolescent girl, using combined rapid maxillary expansion-facemask approach, followed by comprehensive fixed appliance mechanotherapy. Excellent long-term stability is demonstrated up to 5 years post-treatment.
Nada, R.M.; Loon, B. van; Maal, T.J.J.; Berge, S.J.; Mostafa, Y.A.; Kuijpers-Jagtman, A.M.; Schols, J.G.J.H.
2013-01-01
OBJECTIVES: This study seeks to three-dimensionally assess soft tissue changes in the orofacial region following tooth-borne and bone-borne surgically assisted rapid maxillary expansion (SARME). MATERIALS AND METHODS: This prospective cohort study included 40 skeletally mature patients with
International Nuclear Information System (INIS)
Fink, Reinhold F.
2009-01-01
The retaining the excitation degree (RE) partitioning [R.F. Fink, Chem. Phys. Lett. 428 (2006) 461(20 September)] is reformulated and applied to multi-reference cases with complete active space (CAS) reference wave functions. The generalised van Vleck perturbation theory is employed to set up the perturbation equations. It is demonstrated that this leads to a consistent and well defined theory which fulfils all important criteria of a generally applicable ab initio method: The theory is proven numerically and analytically to be size-consistent and invariant with respect to unitary orbital transformations within the inactive, active and virtual orbital spaces. In contrast to most previously proposed multi-reference perturbation theories the necessary condition for a proper perturbation theory to fulfil the zeroth order perturbation equation is exactly satisfied with the RE partitioning itself without additional projectors on configurational spaces. The theory is applied to several excited states of the benchmark systems CH 2 , SiH 2 , and NH 2 , as well as to the lowest states of the carbon, nitrogen and oxygen atoms. In all cases comparisons are made with full configuration interaction results. The multi-reference (MR)-RE method is shown to provide very rapidly converging perturbation series. Energy differences between states of similar configurations converge even faster
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Kathleen Semple Delaney
2010-09-01
Full Text Available Urbanization is a major cause of habitat fragmentation worldwide. Ecological and conservation theory predicts many potential impacts of habitat fragmentation on natural populations, including genetic impacts. Habitat fragmentation by urbanization causes populations of animals and plants to be isolated in patches of suitable habitat that are surrounded by non-native vegetation or severely altered vegetation, asphalt, concrete, and human structures. This can lead to genetic divergence between patches and in turn to decreased genetic diversity within patches through genetic drift and inbreeding.We examined population genetic patterns using microsatellites in four common vertebrate species, three lizards and one bird, in highly fragmented urban southern California. Despite significant phylogenetic, ecological, and mobility differences between these species, all four showed similar and significant reductions in gene flow over relatively short geographic and temporal scales. For all four species, the greatest genetic divergence was found where development was oldest and most intensive. All four animals also showed significant reduction in gene flow associated with intervening roads and freeways, the degree of patch isolation, and the time since isolation.Despite wide acceptance of the idea in principle, evidence of significant population genetic changes associated with fragmentation at small spatial and temporal scales has been rare, even in smaller terrestrial vertebrates, and especially for birds. Given the striking pattern of similar and rapid effects across four common and widespread species, including a volant bird, intense urbanization may represent the most severe form of fragmentation, with minimal effective movement through the urban matrix.
Rosa, Cristiane Becher; Habib, Fernando Antonio Lima; de Araújo, Telma Martins; Aragão, Juliana Silveira; Gomes, Rafael Soares; Barbosa, Artur Felipe Santos; Silveira, Landulfo; Pinheiro, Antonio L B
2014-05-01
The aim of this study was to analyze the effect of laser or light-emitting diode (LED) phototherapy on the bone formation at the midpalatal suture after rapid maxilla expansion. Twenty young adult male rats were divided into four groups with 8 days of experimental time: group 1, no treatment; group 2, expansion; group 3, expansion and laser irradiation; and group 4, expansion and LED irradiation. In groups 3 and 4, light irradiation was in the first, third, and fifth experimental days. In all groups, the expansion was accomplished with a helicoid 0.020" stainless steel orthodontic spring. A diode laser (λ780 nm, 70 mW, spot of 0.04 cm(2), t = 257 s, spatial average energy fluence (SAEF) of 18 J/cm(2)) or a LED (λ850 nm, 150 mW ± 10 mW, spot of 0.5 cm(2), t = 120 s, SAEF of 18 J/cm(2)) were used. The samples were analyzed by Raman spectroscopy carried out at midpalatal suture and at the cortical area close to the suture. Two Raman shifts were analyzed: ∼ 960 (phosphate hydroxyapatite) and ∼ 1,450 cm(-1) (lipids and protein). Data was submitted to statistical analysis. Significant statistical difference (p ≤ 0.05) was found in the hydroxyapatite (CHA) peaks among the expansion group and the expansion and laser or LED groups. The LED group presented higher mean peak values of CHA. No statistical differences were found between the treated groups as for collagen deposition, although LED also presented higher mean peak values. The results of this study using Raman spectral analysis indicate that laser and LED light irradiation improves deposition of CHA in the midpalatal suture after orthopedic expansion.
Indian Academy of Sciences (India)
First page Back Continue Last page Overview Graphics. Network Convergence. User is interested in application and content - not technical means of distribution. Boundaries between distribution channels fade out. Network convergence leads to seamless application and content solutions.
Directory of Open Access Journals (Sweden)
Anand Ramchandra Rathi
2015-01-01
Full Text Available Class III malocclusion is very common malocclusion and can be due to maxillary retrusion, mandibular prognathism, or combination. Ellis and McNamara found a combination of maxillary retrusion and mandibular protrusion to be the most common skeletal relationship (30%. The treatment should be carried out as early as possible for permitting normal growth of the skeletal bases. Reverse pull head gear combined with maxillary expansion can effectively correct skeletal Class III malocclusion due to maxillary deficiency in growing patient. An eight-year-old female patient with chief complaint of prognathic mandible and anterior crossbite was successfully treated in duration of 5 months with facemask and expansion therapy based on Alternate Rapid Maxillary Expansion and Constriction (Alt-RAMEC protocol.
Sergeev, A.; Alharbi, F. H.; Jovanovic, R.; Kais, S.
2016-04-01
The gradient expansion of the kinetic energy density functional, when applied to atoms or finite systems, usually grossly overestimates the energy in the fourth order and generally diverges in the sixth order. We avoid the divergence of the integral by replacing the asymptotic series including the sixth order term in the integrand by a rational function. Padé approximants show moderate improvements in accuracy in comparison with partial sums of the series. The results are discussed for atoms and Hooke’s law model for two-electron atoms.
Das, Susanta; Nam, Kwangho; Major, Dan Thomas
2018-03-13
In recent years, a number of quantum mechanical-molecular mechanical (QM/MM) enzyme studies have investigated the dependence of reaction energetics on the size of the QM region using energy and free energy calculations. In this study, we revisit the question of QM region size dependence in QM/MM simulations within the context of energy and free energy calculations using a proton transfer in a DNA base pair as a test case. In the simulations, the QM region was treated with a dispersion-corrected AM1/d-PhoT Hamiltonian, which was developed to accurately describe phosphoryl and proton transfer reactions, in conjunction with an electrostatic embedding scheme using the particle-mesh Ewald summation method. With this rigorous QM/MM potential, we performed rather extensive QM/MM sampling, and found that the free energy reaction profiles converge rapidly with respect to the QM region size within ca. ±1 kcal/mol. This finding suggests that the strategy of QM/MM simulations with reasonably sized and selected QM regions, which has been employed for over four decades, is a valid approach for modeling complex biomolecular systems. We point to possible causes for the sensitivity of the energy and free energy calculations to the size of the QM region, and potential implications.
Ziapour, Behrad; Haji, Houman Seyedjavady
2015-01-01
Occult pneumothorax represents a diagnostic pitfall during the primary survey of trauma patients, particularly if these patients require early positive pressure ventilation. This study investigated the accuracy of our proposed rapid model of ultrasound transducer positioning during the primary survey of trauma patients after their arrival at the hospital. This diagnostic trial was conducted over 12 months and was based on the results of 84 ultrasound (US) exams performed on patients with severe multiple trauma. Our index test (US) was used to detect pneumothorax in four pre-defined locations on the anterior of each hemi-thorax using the "Anterior Convergent" approach, and its performance was limited to the primary survey. Consecutively, patients underwent chest-computed tomography (CT) with or without chest radiography. The diagnostic findings of both chest radiography and chest ultrasounds were compared to the gold-standard test (CT). The diagnostic sensitivity was 78 % for US and 36.4 % for chest radiography (p chest radiography (not significant); the positive predictive values were 74 % for US and 80 % for chest radiography (not significant); the negative predictive values were 94 % for US and 87 % for chest radiography (not significant); the positive likelihood ratio was 10 for US and 18 for chest radiography (p = 0.007); and the negative likelihood ratio was 0.25 for US and 0.65 for chest radiography (p = 0.001). The mean required time for performing the new method was 64 ± 10 s. An absence of the expected diffused dynamic view among ultrasound images obtained from patients with pneumothorax was also observed. We designated this phenomenon "Gestalt Lung Recession." "Anterior convergent" chest US probing represents a brief but efficient model that provides clinicians a safe and accurate exam and adequate resuscitation during critical minutes of the primary survey without interrupting other medical staff activities taking place around the
Seeberger, Robin; Gander, Evelyn; Hoffmann, Jürgen; Engel, Michael
2015-09-01
The surgical treatment of cross-bites includes surgically-assisted maxillary expansion (SARME) or maxillary-bipartition during bimaxillary surgery. This study evaluates and compares the changes in the teeth and lower nasal passage, as well as the stability of the expansion. The measurements were performed on the cone-beam computed tomography (CBCT) scans of 32 patients with transverse (width) deficiencies of the maxilla. To expand the maxilla, 12 patients underwent the two-piece maxilla method, while 20 patients received SARME. The mean distraction width for SARME was 6.8 mm (SD 3.7), while that for the two-piece maxilla was 4.1 mm (SD 1.6). The expansion with SARME was over the entire length of the maxilla, from anterior to posterior, whereas the expansion of the two-piece patient group was only in the posterior part of the maxilla. The segments of the maxilla opened nearly parallel in SARME, while they were reverse V-shaped in the two-piece maxilla, from anterior to posterior. A key point in the planning of combined orthodontic-orthognathic therapy with surgical correction of a cross-bite is the precise determination of the area where the width needs to be increased, and the amount of correction needed to treat the patient using minimal surgical procedures. Copyright © 2015 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.
Deng, Huimin; Yang, Fei; Li, Zhonghao; Bian, Zhaoyang; Fan, Ziyan; Wang, Ying; Liu, Shanshan; Tang, Gangling
2017-07-21
Aromatic amines in mainstream cigarette smoke have long been monitored due to their carcinogenic toxicity. In this work, a reliable and rapid method was developed for the simultaneous determination of 9 aromatic amines in mainstream cigarette smoke by modified dispersive liquid liquid microextraction (DLLME) and ultraperformance convergence chromatography tandem mass spectrometry (UPC 2 -MS/MS). Briefly, the particulate phase of the cigarette smoke was captured by a Cambridge filter pad, and diluted hydrogen chloride aqueous solution is employed to extract the aromatic amines under mechanical shaking. After alkalization with sodium hydroxide solution, small amount of toluene was introduced to further extract and enrich aromatic amines by modified DLLME under vortexing. After centrifugation, toluene phase was purified by a universal QuEChERS cleanup kit and was finally analyzed by UPC 2 -MS/MS. Attributing to the superior performance of UPC 2 -MS/MS, this novel approach allowed the separation and determination of 9 aromatic amines within 5.0min with satisfactory resolution and sensitivity. The proposed method was finally validated using Kentucky reference cigarette 3R4F, and emission levels of targeted aromatic amines determined were comparable to previously reported methods At three different spiked levels, the recoveries of most analytes were ranged from 74.01% to 120.50% with relative standard deviation (RSD) less than 12%, except that the recovery of p-toluidine at low spiked level and 3-aminobiphenyl at medium spiked level was 62.77% and 69.37% respectively. Thus, this work provides a novel alternative method for the simultaneous analysis of 9 aromatic amines in mainstream cigarette smoke. Copyright © 2017 Elsevier B.V. All rights reserved.
Basehore, Monica J; Marlowe, Natalia M; Jones, Julie R; Behlendorf, Deborah E; Laver, Thomas A; Friez, Michael J
2012-06-01
Most individuals with intellectual disability and/or autism are tested for Fragile X syndrome at some point in their lifetime. Greater than 99% of individuals with Fragile X have an expanded CGG trinucleotide repeat motif in the promoter region of the FMR1 gene, and diagnostic testing involves determining the size of the CGG repeat as well as methylation status when an expansion is present. Using a previously described triplet repeat-primed polymerase chain reaction, we have performed additional validation studies using two cohorts with previous diagnostic testing results available for comparison purposes. The first cohort (n=88) consisted of both males and females and had a high percentage of abnormal samples, while the second cohort (n=624) consisted of only females and was not enriched for expansion mutations. Data from each cohort were completely concordant with the results previously obtained during the course of diagnostic testing. This study further demonstrates the utility of using laboratory-developed triplet repeat-primed FMR1 testing in a clinical setting.
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Umarevathi Gopalakrishnan
2017-01-01
Full Text Available Aims and Objectives: The purpose of the study was to assess the skeletal and dental effects of fan-type rapid maxillary expansion (RME appliance and Hyrax RME appliance on the craniofacial structures. Materials and Methods: The sample of the study included 12 patients with constricted maxillary arches. Acrylic bonded type of attachment was used for both groups. Changes in sagittal, vertical, and transverse relationship were assessed with lateral and frontal cephalograms, respectively. Intercanine and intermolar widths were measured with stone models. Pre- and immediate post-treatment records were statistically analyzed with Wilcoxon signed-rank test. The differences between the groups were evaluated using Mann–Whitney U-test. Since the data pertaining to intercanine width and intermolar width were normally distributed, parametric test of signifi cance (unpaired t-test was used to compare them. Results: Results showed that Hyrax presented with signifi cantly greater increments for both nasal cavity width and maxillary width when compared to fan-type RME. Both groups had retroclination of incisors. The increase in the intercanine width was almost similar in both groups. Conclusion: Fan-type RME caused only minimal expansion of the intermolar width when compared to the Hyrax. The ratio between the intercanine and intermolar width expansion was nearly 4:1 in the fan-type RME and 0.75:1 in Hyrax.
Sharma, Rahul; Ju, Angela Chiao-Ying; Kung, John T; Fu, Shu Man; Ju, Shyr-Te
2008-11-15
Foreign Ag-specific TCR-transgenic (Tg) mice contain a small fraction of T cells bearing the endogenous Vbeta and Valpha chains as well as a population expressing an intermediate level of Tg TCR. Importantly, these minor nonclonotypic populations contain > or = 99% of the CD4(+)Foxp3(+) regulatory T cells (Treg) and, despite low overall Treg expression, peripheral tolerance is maintained. In the OT-II TCR (OVA-specific, Vbeta5(high)Valpha2(high)) Tg scurfy (Sf) mice (OT-II Sf) that lack Treg, nonclonotypic T cells markedly expanded in the periphery but not in the thymus. Expanded T cells expressed memory/effector phenotype and were enriched in blood and inflamed lungs. In contrast, Vbeta5(high)Valpha2(high) clonotypic T cells were not expanded, displayed the naive phenotype, and found mainly in the lymph nodes. Importantly, Vbeta5(neg) T cells were able to transfer multiorgan inflammation in Rag1(-/-) recipients. T cells bearing dual TCR (dual Vbeta or dual Valpha) were demonstrated frequently in the Vbeta5(int) and Valpha2(int) populations. Our study demonstrated that in the absence of Treg, the lack of peripheral expansion of clonotypic T cells is due to the absence of its high-affinity Ag OVA. Thus, the rapid expansion of nonclonotypic T cells in OT-II Sf mice must require Ag (self and foreign) with sufficient affinity. Our study has implications with respect to the roles of Ag and dual TCR in the selection and regulation of Treg and Treg-controlled Ag-dependent T cell expansion in TCR Tg and TCR Tg Sf mice, respectively.
A summation procedure for expansions in orthogonal polynomials
International Nuclear Information System (INIS)
Garibotti, C.R.; Grinstein, F.F.
1977-01-01
Approximants to functions defined by formal series expansions in orthogonal polynomials are introduced. They are shown to be convergent even out of the elliptical domain where the original expansion converges
Seo, Yu-Jin; Lin, Lu; Kim, Seong-Hun; Chung, Kyu-Rhim; Nelson, Gerald
2016-01-01
This case report presents the camouflage treatment that successfully improved the facial profile of a patient with a skeletal Class III malocclusion using bone-borne rapid maxillary expansion and mandibular anterior subapical osteotomy. The patient was an 18-year-old woman with chief complaints of crooked teeth and a protruded jaw. Camouflage treatment was chosen because she rejected orthognathic surgery under general anesthesia. A hybrid type of bone-borne rapid maxillary expander with palatal mini-implants was used to correct the transverse discrepancy, and a mandibular anterior subapical osteotomy was conducted to achieve proper overjet with normal incisal inclination and to improve her lip and chin profile. As a result, a Class I occlusion with a favorable inclination of the anterior teeth and a good esthetic profile was achieved with no adverse effects. Therefore, the hybrid type of bone-borne rapid maxillary expander and a mandibular anterior subapical osteotomy can be considered effective camouflage treatment of a skeletal Class III malocclusion, providing improved inclination of the dentition and lip profile. Copyright © 2016 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.
DEFF Research Database (Denmark)
Kjær, Katrine Heinsvig
2012-01-01
to maintain carbohydrate status and growth in unpredictable light environments. Our recent results show rapid regulation of photosynthesis and leaf carbohydrate status to maintain growth and light interception in dynamic light environments when campanula, rose and chrysanthemum were grown in a cost......-efficient light control system. Plant dry matter production was in all cases linear related to DLI, despite changes in daily light duration and light intensity of supplemental light suggesting that DLI is the main limiting factor for the prediction of production time in optimal temperature conditions. The results......Protected plant productions in northern latitudes rely heavily on supplemental light use to extend the number of light hours during the day. To conserve electricity and lower costs, a low-energy input system use supplemental lights preferable during less expensive off-peak hours and turn lighting...
... is also found to be weak. If both accommodation and convergence are weak, reading glasses, sometimes with prism added, may be a great option for these patients. It is very difficult to improve accommodation with exercises. Updated 7/2017 Eye Terms & Conditions ...
Costin, Ovidiu; Dunne, Gerald V.
2018-01-01
We show how to convert divergent series, which typically occur in many applications in physics, into rapidly convergent inverse factorial series. This can be interpreted physically as a novel resummation of perturbative series. Being convergent, these new series allow rigorous extrapolation from an asymptotic region with a large parameter, to the opposite region where the parameter is small. We illustrate the method with various physical examples, and discuss how these convergent series relate to standard methods such as Borel summation, and also how they incorporate the physical Stokes phenomenon. We comment on the relation of these results to Dyson’s physical argument for the divergence of perturbation theory. This approach also leads naturally to a wide class of relations between bosonic and fermionic partition functions, and Klein-Gordon and Dirac determinants.
Baccetti, T; Franchi, L; McNamara, J A
1999-06-01
An effective morphometric method (thin-plate spline analysis) was applied to evaluate shape changes in the craniofacial configuration of a sample of 23 children with Class III malocclusions in the early mixed dentition treated with rapid maxillary expansion and face mask therapy, and compared with a sample of 17 children with untreated Class III malocclusions. Significant treatment-induced changes involved both the maxilla and the mandible. Major deformations consisted of forward displacement of the maxillary complex from the pterygoid region and of anterior morphogenetic rotation of the mandible, due to a significant upward and forward direction of growth of the mandibular condyle. Significant differences in size changes due to reduced increments in mandibular dimensions were associated with significant shape changes in the treated group.
Drygala, Frank; Korablev, Nikolay; Ansorge, Hermann; Fickel, Joerns; Isomursu, Marja; Elmeros, Morten; Kowalczyk, Rafał; Baltrunaite, Laima; Balciauskas, Linas; Saarma, Urmas; Schulze, Christoph; Borkenhagen, Peter; Frantz, Alain C.
2016-01-01
The extent of gene flow during the range expansion of non-native species influences the amount of genetic diversity retained in expanding populations. Here, we analyse the population genetic structure of the raccoon dog (Nyctereutes procyonoides) in north-eastern and central Europe. This invasive species is of management concern because it is highly susceptible to fox rabies and an important secondary host of the virus. We hypothesized that the large number of introduced animals and the species’ dispersal capabilities led to high population connectivity and maintenance of genetic diversity throughout the invaded range. We genotyped 332 tissue samples from seven European countries using 16 microsatellite loci. Different algorithms identified three genetic clusters corresponding to Finland, Denmark and a large ‘central’ population that reached from introduction areas in western Russia to northern Germany. Cluster assignments provided evidence of long-distance dispersal. The results of an Approximate Bayesian Computation analysis supported a scenario of equal effective population sizes among different pre-defined populations in the large central cluster. Our results are in line with strong gene flow and secondary admixture between neighbouring demes leading to reduced genetic structuring, probably a result of its fairly rapid population expansion after introduction. The results presented here are remarkable in the sense that we identified a homogenous genetic cluster inhabiting an area stretching over more than 1500km. They are also relevant for disease management, as in the event of a significant rabies outbreak, there is a great risk of a rapid virus spread among raccoon dog populations. PMID:27064784
Liflyand, E.
2012-01-01
We study an extension to Fourier transforms of the old problem on absolute convergence of the re-expansion in the sine (cosine) Fourier series of an absolutely convergent cosine (sine) Fourier series. The results are obtained by revealing certain relations between the Fourier transforms and their Hilbert transforms.
Sigler, Lauren M; Baccetti, Tiziano; McNamara, James A
2011-03-01
Our aim was to investigate the effect of rapid maxillary expansion and transpalatal arch therapy combined with deciduous canine extraction on the eruption rate of palatally displaced canines (PDCs) in patients in the late mixed dentition in a 2-center prospective study. Seventy subjects were enrolled based on PDCs diagnosed on panoramic radiographs. The treatment group (TG, 40 subjects) underwent RME followed by TPA therapy and extraction of the deciduous canines. The control group (CG, 30 subjects) received no orthodontic treatment. At the start of the trial, panoramic radiographs and dental casts were compared between the TG and the CG with the Mann-Whitney U test (P anomalies was reported. No statistically significant difference was found for any measurement at the start of the trial between the 2 groups. The prevalence rates of eruption of the maxillary canines were 80% for the TG and 28% in the CG, a statistically significant difference (chi-square =16.26, P mixed dentition with PDCs. Pretreatment variables indicating success of treatment on the eruption of PDCs were less severe sectors of displacement, prepubertal stages of skeletal maturity, and open root apices of PDCs. Several dental anomalies were associated significantly with PDCs, thus confirming the genetic etiology of this eruption disturbance. Copyright © 2011 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.
Directory of Open Access Journals (Sweden)
Sunbong Lee
2014-06-01
Full Text Available Bio-oil (bio-oil was produced from chicken manure in a pilot-scale pyrolysis facility. The raw bio-oil had a very high viscosity and sediments which made direct application to diesel engines difficult. The bio-oil was blended with diesel fuel with 25% and 75% volumetric ratio at the normal temperature, named as blend 25. A rapid compression and expansion machine was used for a combustion test under the experimental condition corresponding to the medium operation point of a light duty diesel engine using diesel fuel, and blend 25 for comparison. The injection related pressure signal and cylinder pressure signal were instantaneously picked up to analyze the combustion characteristics in addition to the measurement of NOx and smoke emissions. Blend 25 resulted in reduction of the smoke emission by 80% and improvements of the apparent combustion efficiency while the NOx emission increased by 40%. A discussion was done based on the analysis results of combustion.
Directory of Open Access Journals (Sweden)
Daniella Torres Tagawa
2012-06-01
Full Text Available OBJECTIVE: The aim of this prospective study was to assess potential changes in the cephalometric craniofacial growth pattern of 17 children presenting Angle Class III malocclusion treated with a Haas-type expander combined with a face mask. METHODS: Lateral cephalometric radiographs were taken at beginning (T1 and immediately after removal of the appliances (T2, average of 11 months of treatment. Linear and angular measurements were used to evaluate the cranial base, dentoskeletal changes and facial growth pattern. RESULTS: The length of the anterior cranial base experienced a reduction while the posterior cranial base assumed a more vertical position at T1. Some maxillary movement occurred, there was no rotation of the palatal plane, there was a slight clockwise rotation of the mandible, although not significant. The ANB angle increased, thereby improving the relationship between the jaws; dentoalveolar compensation was more evident in the lower incisors. Five out of 12 cases (29.41% showed the following changes: In one case the pattern became more horizontal and in four cases more vertical. CONCLUSIONS: It was concluded after a short-term assessment that treatment with rapid maxillary expansion (RME associated with a face mask was effective in the correction of Class III malocclusion despite the changes in facial growth pattern observed in a few cases.
Energy Technology Data Exchange (ETDEWEB)
Gamble, Jennifer; Lagravere, Manuel O.; Major, Paul W.; Heo, Giseon [University of Alberta, Edmonton (Canada)
2012-03-15
To describe a statistical method of three-dimensional landmark configuration data and apply it to an orthodontic data set comparing two types of rapid maxillary expansion (RME) treatments. Landmark configurations obtained from cone beam CT scans were used to represent patients in two types (please describe what were two types) of RME groups and a control group over four time points. A method using tools from persistent homology and dimensionality reduction is presented and used to identify variability between the subjects. The analysis was in agreement with previous results using conventional methods, which found significant differences between treatment groups and the control, but no distinction between the types of treatment. Additionally, it was found that second molar eruption varied considerably between the subjects, and this has not been evaluated in previous analyses. This method of analysis allows entire configurations to be considered as a whole, and does not require specific inter-landmark distances or angles to be selected. Sources of variability present themselves, without having to be individually sought after. This method is suggested as an additional tool for the analysis of landmark configuration data.
Do convergent developmental mechanisms underlie convergent phenotypes?
Wray, Gregory A.
2002-01-01
Convergence is a pervasive evolutionary process, affecting many aspects of phenotype and even genotype. Relatively little is known about convergence in developmental processes, however, nor about the degree to which convergence in development underlies convergence in anatomy. A switch in the ecology of sea urchins from feeding to nonfeeding larvae illustrates how convergence in development can be associated with convergence in anatomy. Comparisons to more distantly related taxa, however, suggest that this association may be limited to relatively close phylogenetic comparisons. Similarities in gene expression during development provide another window into the association between convergence in developmental processes and convergence in anatomy. Several well-studied transcription factors exhibit likely cases of convergent gene expression in distantly related animal phyla. Convergence in regulatory gene expression domains is probably more common than generally acknowledged, and can arise for several different reasons. Copyright 2002 S. Karger AG, Basel.
Separable pole expansions in four-nucleon bound state calculations
International Nuclear Information System (INIS)
Sofianos, S.A.; Fiedeldey, H.; Haberzettl, H.; Sandhas, W.
1982-04-01
We compare the utility of the Generalized Unitary Pole Expansion (GUPE) and the Energy-Dependent Pole Expansion (EDPE) for the three-body subsystem amplitudes in four-body state calculations for a variety of separable and local nucleon-nucleon interactions. It is found that, with the EDPE, the four-body binding energy is well reproduced with only two terms each for the (2+2)- and the (3+1)-subsystem, respectively, while the GUPE requires three terms for the (3+1)-channel and four terms for the (2+2)-channel. We thus conclude that pole dominance is of greater importance for the GUPE than for EDPE, which works equally well for both types of subsystems. It is found that both methods, in particular the EDPE, converge more rapidly with increasing repulsion in the two-body interaction, i.e. the more realistic the interaction becomes. Both expansions require similar computing times for a converged calculation and are about 15-20 times faster than the widely used Hilbert-Schmidt Expansion (HSE). The respective merits of the two pole expansions are discussed and compared with the HSE. (orig.)
Ghoussoub, Mona Sayegh; Rifai, Khaldoun; Garcia, Robert; Sleilaty, Ghassan
2018-01-01
Aims and Objectives: Rapid maxillary expansion (RME) is an orthodontic nonsurgical procedure aiming at increasing the width of the maxilla by opening mainly the intermaxillary suture in patients presenting a transverse maxillary skeletal deficiency. The objectives of the current prospective controlled clinical and radiographic study are to evaluate the hypothesis that RME in growing patients will result in radiographic changes at the level of interglenoid fossa distance, condyle-fossa relationship, and nasal cavity widths compared to the group who received no treatment initially and served as untreated control. Materials and Methods: In this prospective controlled clinical and radiographic study, forty healthy growing patients selected from a school-based population following a large screening campaign, ranging in age between 8 and 13 years, presenting a maxillary constriction with bilateral crossbite, and candidates for RME are being recruited. The first group will include participants willing to undergo treatment (n = 25) and the other group will include those inclined to postpone (n = 15). Results: The primary outcome is to compare radiologically the interglenoid fossa distance and the condyle-fossa relationship; nasal cavity width will be a secondary outcome. A multivariable analysis of Covariance model will be used, with the assessment of the time by group interaction, using age as covariate. The project protocol was reviewed and approved by the Ethics Committee of the Lebanese University, National Institute in Lebanon (CUEMB process number 31/04/2015). The study is funded by the Lebanese University and Centre National de Recherche Scientifique, Lebanon (Number: 652 on 14/04/2016). Conclusion: This prospective controlled clinical trial will give information about the effect of RME on the glenoid fossa and condyle-fossa relationship and its impact on the nasal cavity width. Trial Registration: Retrospectively registered in BioMed Central (DOI10.1186/ISRCTN
Convergence in Multispecies Interactions
Bittleston, Leonora Sophia; Pierce, Naomi E.; Ellison, Aaron M.; Pringle, Anne
2016-01-01
The concepts of convergent evolution and community convergence highlight how selective pressures can shape unrelated organisms or communities in similar ways. We propose a related concept, convergent interactions, to describe the independent evolution of multispecies interactions with similar physiological or ecological functions. A focus on convergent interactions clarifies how natural selection repeatedly favors particular kinds of associations among species. Characterizing convergent inter...
Gopalakrishnan, T.; Saravanan, R.
2017-03-01
Powerful management concepts step-up the quality of the product, time saving in producing the product thereby increase the production rate, improves tools and techniques, work culture, work place and employee motivation and morale. In this paper discussed about the case study of optimizing the tool design, tool parameters to cast off expansion plan according ECRS technique. The proposed designs and optimal tool parameters yielded best results and meet the customer demand without expansion plan. Hence the work yielded huge savings of money (direct and indirect cost), time and improved the motivation and more of employees significantly.
Boson expansion theory in the seniority scheme
International Nuclear Information System (INIS)
Tamura, T.; Li, C.; Pedrocchi, V.G.
1985-01-01
A boson expansion formalism in the seniority scheme is presented and its relation with number-conserving quasiparticle calculations is elucidated. Accuracy and convergence are demonstrated numerically. A comparative discussion with other related approaches is given
Van der Jeugd, H.P.; Eichhorn, Goetz; Litvin, K.E.; Stahl, J.; Larsson, K.; van der Graaf, A.J.; Drent, R.H.
2009-01-01
Within three decades, the barnacle goose population wintering on the European mainland has dramatically increased in numbers and extended its breeding range. The expansion has occurred both within the Arctic as well as by the colonization of temperate areas. Studies of performance of individuals in
Van Der Jeugd, Henk P.; Eichhorn, Gotz; Litvin, Konstantin E.; Stahl, Julia; Larsson, Kjell; Van Der Graaf, Alexandra J.; Drent, Rudi H.
Within three decades, the barnacle goose population wintering on the European mainland has dramatically increased in numbers and extended its breeding range. The expansion has occurred both within the Arctic as well as by the colonization of temperate areas. Studies of performance of individuals in
Explicit Formulae for the Continued Fraction Convergents of "Square Root of D"
Braza, Peter A.
2010-01-01
The formulae for the convergents of continued fractions are always given recursively rather than in explicit form. This article derives explicit formulae for the convergents of the continued fraction expansions for square roots.
Leptodermous expansion of finite-nucleus incompressibility
International Nuclear Information System (INIS)
Nayak, R.C.
1990-01-01
We consider the influence of higher-order terms in the leptodermous expansion used to extract the incompressibility K v of infinite nuclear matter from data on the breathing mode of finite nuclei. The terms we calculate are the curvature term K cv A -2/3 , the surface-symmetry term K ss I 2 A -1/3 , the quartic volume-symmetry term K 4 I 4 , and a Coulomb-exchange term. Working within the framework of the scaling model we derive expressions for their coefficients in terms of quantities that are defined for infinite and semi-infinite nuclear matter. We calculate these coefficients for four different Skyrme-type forces, using the extended Thomas-Fermi (ETF) approximation. With the same forces we also calculate the incompressibility K (A, I) for a number of finite nuclei, fit the results to the leptodermous expansion, and thereby extract new results for the same coefficients. The comparison of the two calculations shows that the leptodermous expansion is converging rapidly. Of the new terms, the term K 4 I 4 is quite negligible, the curvature term should be included, and we discuss to what extent the other higher-order terms are significant. (orig.)
Tate, Stephen James
2013-10-01
In the 1960s, the technique of using cluster expansion bounds in order to achieve bounds on the virial expansion was developed by Lebowitz and Penrose (J. Math. Phys. 5:841, 1964) and Ruelle (Statistical Mechanics: Rigorous Results. Benjamin, Elmsford, 1969). This technique is generalised to more recent cluster expansion bounds by Poghosyan and Ueltschi (J. Math. Phys. 50:053509, 2009), which are related to the work of Procacci (J. Stat. Phys. 129:171, 2007) and the tree-graph identity, detailed by Brydges (Phénomènes Critiques, Systèmes Aléatoires, Théories de Jauge. Les Houches 1984, pp. 129-183, 1986). The bounds achieved by Lebowitz and Penrose can also be sharpened by doing the actual optimisation and achieving expressions in terms of the Lambert W-function. The different bound from the cluster expansion shows some improvements for bounds on the convergence of the virial expansion in the case of positive potentials, which are allowed to have a hard core.
International Nuclear Information System (INIS)
Lind, P.
1993-02-01
The completeness properties of the discrete set of bound state, virtual states and resonances characterizing the system of a single nonrelativistic particle moving in a central cutoff potential is investigated. From a completeness relation in terms of these discrete states and complex scattering states one can derive several Resonant State Expansions (RSE). It is interesting to obtain purely discrete expansion which, if valid, would significantly simplify the treatment of the continuum. Such expansions can be derived using Mittag-Leffler (ML) theory for a cutoff potential and it would be nice to see if one can obtain the same expansions starting from an eigenfunction theory that is not restricted to a finite sphere. The RSE of Greens functions is especially important, e.g. in the continuum RPA (CRPA) method of treating giant resonances in nuclear physics. The convergence of RSE is studied in simple cases using square well wavefunctions in order to achieve high numerical accuracy. Several expansions can be derived from each other by using the theory of analytic functions and one can the see how to obtain a natural discretization of the continuum. Since the resonance wavefunctions are oscillating with an exponentially increasing amplitude, and therefore have to be interpreted through some regularization procedure, every statement made about quantities involving such states is checked by numerical calculations.Realistic nuclear wavefunctions, generated by a Wood-Saxon potential, are used to test also the usefulness of RSE in a realistic nuclear calculation. There are some fundamental differences between different symmetries of the integral contour that defines the continuum in RSE. One kind of symmetry is necessary to have an expansion of the unity operator that is idempotent. Another symmetry must be used if we want purely discrete expansions. These are found to be of the same form as given by ML. (29 refs.)
Vera, Juan F.; Brenner, Lara J.; Gerdemann, Ulrike; Ngo, Minhtran C.; Sili, Uluhan; Liu, Hao; Wilson, John; Dotti, Gianpietro; Heslop, Helen E.; Leen, Ann M.; Rooney, Cliona M.
2009-01-01
The clinical manufacture of antigen-specific cytotoxic T lymphocytes (CTL) for adoptive immunotherapy is limited by the complexity and time required to produce large numbers with the desired function and specificity. The culture conditions required are rigorous, and in some cases only achieved in 2cm2 wells in which cell growth is limited by gas exchange, nutrients and waste accumulation. Bioreactors developed to overcome these issues tend to be complex, expensive and not always conducive to CTL growth. We observed that antigen-specific CTL undergo seven to ten divisions post-stimulation. However the expected CTL numbers were achieved only in the first week of culture. By recreating the culture conditions present during this first week - low frequency of antigen-specific T-cells and high frequency of feeder cells - we were able to increase CTL expansion to expected levels which could be sustained for several weeks without affecting phenotype or function. However, the number of 24-well plates needed was excessive and cultures required frequent media changes, increasing complexity and manufacturing costs. Therefore, we evaluated novel gas-permeable culture devices (G-Rex) with a silicone membrane at the base allowing gas exchange to occur uninhibited by depth of medium above. This system effectively supports the expansion of CTL and actually increases output by up to 20-fold while decreasing required technician time. Importantly, this amplified cell expansion is not due to more cell divisions but to reduced cell death. This bioprocess optimization increased T-cell output while decreasing the complexity and cost of CTL manufacture, making cell therapy more accessible. PMID:20445351
A survey of Strong Convergent Schemes for the Simulation of ...
African Journals Online (AJOL)
We considered strong convergent stochastic schemes for the simulation of stochastic differential equations. The stochastic Taylor's expansion, which is the main tool used for the derivation of strong convergent schemes; the Euler Maruyama, Milstein scheme, stochastic multistep schemes, Implicit and Explicit schemes were ...
Directory of Open Access Journals (Sweden)
Notermans Ton
2015-02-01
Full Text Available As economic stagnation continues to mark the EU in the fifth year of the euro zone crisis, political support for integration is waning. The European Parliament elections of 2014 returned a hitherto unparalleled number of Eurosceptic MEPs, with EU-critical parties becoming the largest ones in several Member States. Much of this Euroscepticism is driven by economic polarisation between core and peripheral countries. While an increasing number of voters in the northwestern creditor countries resent having to foot the bill for what they consider economic mismanagement in the periphery, voters in peripheral countries increasingly rebel against what they deem to be an economically catastrophic Diktat from Germany and its allies. Continued political support for European integration will hinge on successful income convergence in the EU but the current dilemma is that such policies might not be politically feasible. Periods of rapid convergence would seem to suggest that success depends on two main policy strategies. First, a monetary policy that promotes credit for productive purposes, leaves inflation control to other instruments, and employs selective credit rationing to prevent asset booms. Second, a vertical industrial policy prioritising selected industrial sectors. The first policy conflicts with the present framework of euro zone monetary policy, but that framework was only installed in the first place because many peripheral countries were desperately in search of an external constraint on domestic distributional conflict. Industrial policies, in turn, require a sufficient degree of state autonomy from business elites in order to be effective, but it is highly questionable whether most states in the EU possess such autonomy. Though there are, as yet hesitant, signs of a reorientation of both monetary and cohesion policy in the EU, the question of the institutional and political preconditions for their successful implementation has been largely
International Nuclear Information System (INIS)
Yun, Y.
2015-01-01
Thermal expansion of fuel pellet is an important property which limits the lifetime of the fuels in reactors, because it affects both the pellet and cladding mechanical interaction and the gap conductivity. By fitting a number of available measured data, recommended equations have been presented and successfully used to estimate thermal expansion coefficient of the nuclear fuel pellet. However, due to large scatter of the measured data, non-consensus data have been omitted in formulating the equations. Also, the equation is strongly governed by the lack of appropriate experimental data. For those reasons, it is important to develop theoretical methodologies to better describe thermal expansion behaviour of nuclear fuel. In particular, first-principles and molecular dynamics simulations have been certainly contributed to predict reliable thermal expansion without fitting the measured data. Furthermore, the two theoretical techniques have improved on understanding the change of fuel dimension by describing the atomic-scale processes associated with lattice expansion in the fuels. (author)
Separable expansions for local potentials with Coulomb interactions
International Nuclear Information System (INIS)
Adhikari, S.K.
1976-01-01
If two particles are interacting via a short range potential and a repulsive Coulomb potential the t matrix can be written as a sum of the Coulomb and the ''nuclear'' t matrices. In order to solve the three-nucleon problem with Coulomb interactions usually we need a separable representation of this ''nuclear'' t matrix. A recently proposed method for finding a separable expansion for local potentials is here extended to find a rapidly convergent separable expansion, with analytic form factors, for the ''nuclear'' part of the t matrix of a local potential, in the presence of Coulomb interactions. The method is illustrated for a two-term Malfliet-Tjon potential. In each rank the ''nuclear'' phase shift is close to the corresponding phase shift when the Coulomb interaction is switched off
Discrete expansions of continuum functions. General concepts
International Nuclear Information System (INIS)
Bang, J.; Ershov, S.N.; Gareev, F.A.; Kazacha, G.S.
1979-01-01
Different discrete expansions of the continuum wave functions are considered: pole expansion (according to the Mittag-Lefler theorem), Weinberg states. The general property of these groups of states is their completeness in the finite region of space. They satisfy the Schroedinger type equations and are matched with free solutions of the Schroedinger equation at the boundary. Convergence of expansions for the S matrix, the Green functions and the continuous-spectrum wave functions is studied. A new group of states possessing the best convergence is introduced
Paul, Saikat; Singh, Pankaj; Rudramurthy, Shivaprakash M; Chakrabarti, Arunaloke; Ghosh, Anup K
2017-12-01
To standardize the matrix-assisted laser desorption ionization-time of flight mass spectrometry protocols and expansion of existing Bruker Biotyper database for mold identification. Four different sample preparation methods (protocol A, B, C and D) were evaluated. On analyzing each protein extraction method, reliable identification and best log scores were achieved through protocol D. The same protocol was used to identify 153 clinical isolates. Of these 153, 123 (80.3%) were accurately identified by using existing database and remaining 30 (19.7%) were not identified due to unavailability in database. On inclusion of missing main spectrum profile in existing database, all 153 isolates were identified. Matrix-assisted laser desorption ionization-time of flight mass spectrometry can be used for routine identification of clinically important molds.
International Nuclear Information System (INIS)
Mahlab, M.S.
1975-01-01
All the presently available techniques for solving Schroedinger's differential equation for helium-like atoms display poor convergence of the wave function in the neighborhood of the singularities of the Hamiltonian operator. In general most of the methods of solving this equation will converge in the appropriate limit to the exact wave function; however, convergence is slow, especially near the singularities of this differential equation. These difficulties become readily apparent from local energy studies. A technique is presented that avoids these difficulties. The wave function it produces is specifically most accurate at the singularities of the Hamiltonian. The novel aspect of this treatment is the subdivision of the space spanned by the wave function. Different expansions are picked such that they converge rapidly in each of the different subdivisions. These expansions may be constructed in such a way that they obey the boundary conditions in their respective subdivision. Most importantly, all the information available from the recursion relations associated with the differential equation may be incorporated into these expansions. A systematic procedure is presented such that these expansions may be brought together to form a wave function that satisfies all the continuity requirements. An S-state helium wave function was constructed to demonstrate that this method of treatment is feasible, and capable of indefinite systematic improvement. A discussion of several new asymptotic expansions that were constructed for the helium wave function, as well as an improved functional form for the small electron-nucleus wave function, is included in this presentation
Convergence in Multispecies Interactions.
Bittleston, Leonora S; Pierce, Naomi E; Ellison, Aaron M; Pringle, Anne
2016-04-01
The concepts of convergent evolution and community convergence highlight how selective pressures can shape unrelated organisms or communities in similar ways. We propose a related concept, convergent interactions, to describe the independent evolution of multispecies interactions with similar physiological or ecological functions. A focus on convergent interactions clarifies how natural selection repeatedly favors particular kinds of associations among species. Characterizing convergent interactions in a comparative context is likely to facilitate prediction of the ecological roles of organisms (including microbes) in multispecies interactions and selective pressures acting in poorly understood or newly discovered multispecies systems. We illustrate the concept of convergent interactions with examples: vertebrates and their gut bacteria; ectomycorrhizae; insect-fungal-bacterial interactions; pitcher-plant food webs; and ants and ant-plants. Copyright © 2016 Elsevier Ltd. All rights reserved.
Energy Technology Data Exchange (ETDEWEB)
Kamphues, Stephan [Open Grid Europe GmbH, Essen (Germany)
2011-07-01
In the recently published report, the International Energy Agency (Paris, France) resumes that the global gas consumption can increase by more than 50 % up to 2035. The reasons for this rapid increase include: flexible use, best CO{sub 2} emissions from fossil fuels and long-term availability. The final report of the Ethics Commission 'Energy security' comes to the conclusion that natural gas energy will have a supporting function in Germany. Nationally and internationally, it is assumed that gas is an essential part of the energy supply of the next decades.
Correlation expansion: a powerful alternative multiple scattering calculation method
International Nuclear Information System (INIS)
Zhao Haifeng; Wu Ziyu; Sebilleau, Didier
2008-01-01
We introduce a powerful alternative expansion method to perform multiple scattering calculations. In contrast to standard MS series expansion, where the scattering contributions are grouped in terms of scattering order and may diverge in the low energy region, this expansion, called correlation expansion, partitions the scattering process into contributions from different small atom groups and converges at all energies. It converges faster than MS series expansion when the latter is convergent. Furthermore, it takes less memory than the full MS method so it can be used in the near edge region without any divergence problem, even for large clusters. The correlation expansion framework we derive here is very general and can serve to calculate all the elements of the scattering path operator matrix. Photoelectron diffraction calculations in a cluster containing 23 atoms are presented to test the method and compare it to full MS and standard MS series expansion
Converged Registries Solution (CRS)
Department of Veterans Affairs — The Converged Registries platform is a hardware and software architecture designed to host individual patient registries and eliminate duplicative development effort...
Ray convergence in a flux-like propagation formulation.
Harrison, Chris H
2013-06-01
The energy flux formulation of waveguide propagation is closely related to the incoherent mode sum, and its simplicity has led to development of efficient computational algorithms for reverberation and target echo strength, but it lacks the effects of convergence or modal interference. By starting with the coherent mode sum and rejecting the most rapid interference but retaining beats on a scale of a ray cycle distance it is shown that convergence can be included in a hybrid formulation requiring minimal extra computation. Three solutions are offered by evaluating the modal intensity cross terms using Taylor expansions. In the most efficient approach the double summation of the cross terms is reduced to a single numerical sum by solving the other summation analytically. The other two solutions are a local range average and a local depth average. Favorable comparisons are made between these three solutions and the wave model Orca with, and without, spatial averaging in an upward refracting duct. As a by-product, it is shown that the running range average is very close to the mode solution excluding its fringes, given a relation between averaging window size and effective number of modes which, in turn, is related to the waveguide invariant.
Lu, Jianguo; Peatman, Eric; Tang, Haibao; Lewis, Joshua; Liu, Zhanjiang
2012-06-15
Gene duplication has had a major impact on genome evolution. Localized (or tandem) duplication resulting from unequal crossing over and whole genome duplication are believed to be the two dominant mechanisms contributing to vertebrate genome evolution. While much scrutiny has been directed toward discerning patterns indicative of whole-genome duplication events in teleost species, less attention has been paid to the continuous nature of gene duplications and their impact on the size, gene content, functional diversity, and overall architecture of teleost genomes. Here, using a Markov clustering algorithm directed approach we catalogue and analyze patterns of gene duplication in the four model teleost species with chromosomal coordinates: zebrafish, medaka, stickleback, and Tetraodon. Our analyses based on set size, duplication type, synonymous substitution rate (Ks), and gene ontology emphasize shared and lineage-specific patterns of genome evolution via gene duplication. Most strikingly, our analyses highlight the extraordinary duplication and retention rate of recent duplicates in zebrafish and their likely role in the structural and functional expansion of the zebrafish genome. We find that the zebrafish genome is remarkable in its large number of duplicated genes, small duplicate set size, biased Ks distribution toward minimal mutational divergence, and proportion of tandem and intra-chromosomal duplicates when compared with the other teleost model genomes. The observed gene duplication patterns have played significant roles in shaping the architecture of teleost genomes and appear to have contributed to the recent functional diversification and divergence of important physiological processes in zebrafish. We have analyzed gene duplication patterns and duplication types among the available teleost genomes and found that a large number of genes were tandemly and intrachromosomally duplicated, suggesting their origin of independent and continuous duplication
Directory of Open Access Journals (Sweden)
Daniela Gamba Garib
2007-06-01
Full Text Available OBJETIVO: este trabalho apresenta um método para expansão ortopédica da maxila, na dentadura permanente, utilizando implantes como ancoragem. METODOLOGIA: detalharam-se os procedimentos cirúrgicos e laboratoriais da confecção de um expansor com ancoragem dento-óssea em crânio seco humano. Dois implantes de titânio foram colocados na região anterior do palato, e o parafuso Hyrax adaptado de modo que a expansão ancorou-se nos implantes e nos primeiros molares permanentes. RESULTADOS: o experimento laboratorial em crânio seco mostrou que o procedimento apresenta-se anatômica e operacionalmente viável. Os implantes suportaram a força gerada pela ativação do parafuso expansor, redundando na separação transversal das hemimaxilas. CONCLUSÕES: vislumbra-se que a expansão rápida da maxila ancorada em implantes (ERMAI poderá potencializar a eficiência da expansão ortopédica, assim como reduzir o custo periodontal dos procedimentos convencionais de expansão. Futuros estudos clínicos são necessários para testar essas hipóteses.AIM: This study presents a method for maxillary orthopedic expansion, in the permanent dentition, using implants as anchorage. METHODS: Surgical and laboratorial procedures for the construction of a tooth-bone-borne expansor was detailed in a human dry skull. Two titanium implants were placed in the anterior region of the palate and a Hyrax screw was adapted in a way that the expansion was anchored both on the palatal implants and on permanent first molars. RESULTS: The laboratorial experiment in dry skull showed that the procedure is operationally and anatomically possible. The implants supported the force generated by the expansion screw activation and the maxilla halves were transversally split. CONCLUSIONS: Rapid maxillary expansion anchored on implants can increase the efficiency of orthopedic expansion and decrease the periodontal sequela caused by conventional RME. Further clinical studies are
International Nuclear Information System (INIS)
Knoll, J.
1985-10-01
A quantum dynamical model is suggested which describes the expansion and disassembly phase of highly excited compounds formed in energetic heavy-ion collisions. First applications in two space and one time dimensional model world are discussed and qualitatively compared to standard freeze-out concepts. (orig.)
Indian Academy of Sciences (India)
of a system under investigation is to model the system in terms of some ... The organization of the paper is as follows: In §2, a brief account of the (G /G)- expansion ...... It is interesting to note that from the general results, one can easily recover.
Almost convergence of triple sequences
Ayhan Esi; M.Necdet Catalbas
2013-01-01
In this paper we introduce and study the concepts of almost convergence and almost Cauchy for triple sequences. Weshow that the set of almost convergent triple sequences of 0's and 1's is of the first category and also almost everytriple sequence of 0's and 1's is not almost convergent.Keywords: almost convergence, P-convergent, triple sequence.
Hui, Susanta K; Arentsen, Luke; Sueblinvong, Thanasak; Brown, Keenan; Bolan, Pat; Ghebre, Rahel G; Downs, Levi; Shanley, Ryan; Hansen, Karen E; Minenko, Anne G; Takhashi, Yutaka; Yagi, Masashi; Zhang, Yan; Geller, Melissa; Reynolds, Margaret; Lee, Chung K; Blaes, Anne H; Allen, Sharon; Zobel, Bruno Beomonte; Le, Chap; Froelich, Jerry; Rosen, Clifford; Yee, Douglas
2015-04-01
Cancer survivors are at an increased risk for fractures, but lack of effective and economical biomarkers limits quantitative assessments of marrow fat (MF), bone mineral density (BMD) and their relation in response to cytotoxic cancer treatment. We report dual energy CT (DECT) imaging, commonly used for cancer diagnosis, treatment and surveillance, as a novel biomarker of MF and BMD. We validated DECT in pre-clinical and phase I clinical trials and verified with water-fat MRI (WF-MRI), quantitative CT (QCT) and dual-energy X-ray absorptiometry (DXA). Basis material composition framework was validated using water and small-chain alcohols simulating different components of bone marrow. Histologic validation was achieved by measuring percent adipocyte in the cadaver vertebrae and compared with DECT and WF-MRI. For a phase I trial, sixteen patients with gynecologic malignancies (treated with oophorectomy, radiotherapy or chemotherapy) underwent DECT, QCT, WF-MRI and DXA before and 12months after treatment. BMD and MF percent and distribution were quantified in the lumbar vertebrae and the right femoral neck. Measured precision (3mg/cm(3)) was sufficient to distinguish test solutions. Adiposity in cadaver bone histology was highly correlated with MF measured using DECT and WF-MRI (r=0.80 and 0.77, respectively). In the clinical trial, DECT showed high overall correlation (r=0.77, 95% CI: 0.69, 0.83) with WF-MRI. MF increased significantly after treatment (p<0.002). Chemotherapy and radiation caused greater increases in MF than oophorectomy (p<0.032). L4 BMD decreased 14% by DECT, 20% by QCT, but only 5% by DXA (p<0.002 for all). At baseline, we observed a statistically significant inverse association between MF and BMD which was dramatically attenuated after treatment. Our study demonstrated that DECT, similar to WF-MRI, can accurately measure marrow adiposity. Both imaging modalities show rapid increase in MF following cancer treatment. Our results suggest that MF and
Convergence of Nelson diffusions
International Nuclear Information System (INIS)
Dell'Antonio, G.; Posilicano, A.
1991-01-01
Let ψ t , ψ t n , n≥1, be solutions of Schroedinger equations with potentials form-bounded by -1/2 Δ and initial data in H 1 (R d ). Let P, P n , n≥1, be the probability measures on the path space Ω=C(R + , R d ) given by the corresponding Nelson diffusions. We show that if {ψ t n } n≥1 converges to ψ t in H 2 (R d ), uniformly in t over compact intervals, then {P n } n≥1 converges to P in total variation. Moreover, if the potentials are in the Kato class K d , we show that the above result follows from H 1 -convergence of initial data, and K d -convergence of potentials. (orig.)
Identity Expansion and Transcendence
Directory of Open Access Journals (Sweden)
William Sims Bainbridge
2014-05-01
Full Text Available Emerging developments in communications and computing technology may transform the nature of human identity, in the process rendering obsolete the traditional philosophical and scientific frameworks for understanding the nature of individuals and groups. Progress toward an evaluation of this possibility and an appropriate conceptual basis for analyzing it may be derived from two very different but ultimately connected social movements that promote this radical change. One is the governmentally supported exploration of Converging Technologies, based in the unification of nanoscience, biology, information science and cognitive science (NBIC. The other is the Transhumanist movement, which has been criticized as excessively radical yet is primarily conducted as a dignified intellectual discussion within a new school of philosophy about human enhancement. Together, NBIC and Transhumanism suggest the immense transformative power of today’s technologies, through which individuals may explore multiple identities by means of online avatars, semi-autonomous intelligent agents, and other identity expansions.
Fixed mobile convergence handbook
Ahson, Syed A
2010-01-01
From basic concepts to future directions, this handbook provides technical information on all aspects of fixed-mobile convergence (FMC). The book examines such topics as integrated management architecture, business trends and strategic implications for service providers, personal area networks, mobile controlled handover methods, SIP-based session mobility, and supervisory and notification aggregator service. Case studies are used to illustrate technical and systematic implementation of unified and rationalized internet access by fixed-mobile network convergence. The text examines the technolo
Scaling behavior of ground-state energy cluster expansion for linear polyenes
Griffin, L. L.; Wu, Jian; Klein, D. J.; Schmalz, T. G.; Bytautas, L.
Ground-state energies for linear-chain polyenes are additively expanded in a sequence of terms for chemically relevant conjugated substructures of increasing size. The asymptotic behavior of the large-substructure limit (i.e., high-polymer limit) is investigated as a means of characterizing the rapidity of convergence and consequent utility of this energy cluster expansion. Consideration is directed to computations via: simple Hückel theory, a refined Hückel scheme with geometry optimization, restricted Hartree-Fock self-consistent field (RHF-SCF) solutions of fixed bond-length Parisier-Parr-Pople (PPP)/Hubbard models, and ab initio SCF approaches with and without geometry optimization. The cluster expansion in what might be described as the more "refined" approaches appears to lead to qualitatively more rapid convergence: exponentially fast as opposed to an inverse power at the simple Hückel or SCF-Hubbard levels. The substructural energy cluster expansion then seems to merit special attention. Its possible utility in making accurate extrapolations from finite systems to extended polymers is noted.
International Nuclear Information System (INIS)
2012-12-01
This book explains IT-BT convergence technology as the future technology, which includes a prolog, easy IT-BT convergence technology that has infinite potentials for new value, policy of IT-BT convergence technology showing the potential of smart Korea, IT-BT convergence opening happy future, for the new future of IT powerful nation Korea with IT-BT convergence technology and an epilogue. This book reveals the conception, policy, performance and future of IT-BT convergence technology.
Directory of Open Access Journals (Sweden)
Daniela Gamba Garib
2005-08-01
Full Text Available Este trabalho descreve os efeitos dentoesqueléticos e periodontais da expansão rápida da maxila (ERM, avaliados por meio da tomografia computadorizada (TC, em uma jovem de 11,6 anos de idade com má oclusão de Classe I e mordida cruzada posterior unilateral funcional. Durante a fase ativa da ERM, o expansor dentossuportado com parafuso Hyrax foi ativado 7mm. A paciente submeteu-se ao exame de TC helicoidal, antes da expansão e após a remoção do aparelho expansor, findo o período de três meses de contenção. Realizaram-se cortes axiais, de um milímetro de espessura, paralelamente ao plano palatino, englobando as regiões dentoalveolar e basal da maxila, até o terço inferior da cavidade nasal. Utilizando-se o recurso de reconstruções multiplanares, mensuraram-se pelo método computadorizado: as dimensões transversas maxilares, a inclinação dos dentes posteriores, a espessura das tábuas ósseas vestibular e lingual, e o nível da crista óssea alveolar vestibular. A expansão rápida da maaxila ocasionou um significante aumento transverso em todas as regiões aferidas, com magnitude decrescente do arco dentário para a base óssea. Os dentes posteriores foram movimentados para vestibular, com um componente de inclinação e translação associados. Tal efeito ortodôntico ocasionou uma redução na espessura da tábua óssea vestibular, e um concomitante aumento na espessura da tábua óssea lingual. Após a expansão, observou-se o desenvolvimento de deiscências ósseas por vestibular dos dentes de ancoragem.This paper presents a computed tomography (CT evaluation of rapid maxillary expansion dentoskeletal and periodontal effects, in a 11.6 year-old girl presenting Class I malocclusion with posterior unilateral crossbite. The tooth-borne expander with Hyrax screw was activated 7-mm. The patient was submitted to helicoidal CT scan before expansion and after the three-month retention period when the expander was removed. Axial
Field convergence between technical writers and technical translators
DEFF Research Database (Denmark)
Gnecchi, M.; Maylath, B.; Mousten, Birthe
2011-01-01
As translation of technical documents continues to grow rapidly and translation becomes more automated, the roles of professional communicators and translators appear to be converging. This paper updates preliminary findings first presented at the 2008 International Professional Communication...
Yao, Qiu-Yang; Xia, En-Hua; Liu, Fei-Hu; Gao, Li-Zhi
2015-02-15
WRKY transcription factors (TFs), one of the ten largest TF families in higher plants, play important roles in regulating plant development and resistance. To date, little is known about the WRKY TF family in Brassica oleracea. Recently, the completed genome sequence of cabbage (B. oleracea var. capitata) allows us to systematically analyze WRKY genes in this species. A total of 148 WRKY genes were characterized and classified into seven subgroups that belong to three major groups. Phylogenetic and synteny analyses revealed that the repertoire of cabbage WRKY genes was derived from a common ancestor shared with Arabidopsis thaliana. The B. oleracea WRKY genes were found to be preferentially retained after the whole-genome triplication (WGT) event in its recent ancestor, suggesting that the WGT event had largely contributed to a rapid expansion of the WRKY gene family in B. oleracea. The analysis of RNA-Seq data from various tissues (i.e., roots, stems, leaves, buds, flowers and siliques) revealed that most of the identified WRKY genes were positively expressed in cabbage, and a large portion of them exhibited patterns of differential and tissue-specific expression, demonstrating that these gene members might play essential roles in plant developmental processes. Comparative analysis of the expression level among duplicated genes showed that gene expression divergence was evidently presented among cabbage WRKY paralogs, indicating functional divergence of these duplicated WRKY genes. Copyright © 2014 Elsevier B.V. All rights reserved.
Directory of Open Access Journals (Sweden)
Abdul Hameed Q. A. Al-Tai
2011-01-01
Full Text Available The aim of this paper is to introduce and study the fuzzy neighborhood, the limit fuzzy number, the convergent fuzzy sequence, the bounded fuzzy sequence, and the Cauchy fuzzy sequence on the base which is adopted by Abdul Hameed (every real number r is replaced by a fuzzy number r¯ (either triangular fuzzy number or singleton fuzzy set (fuzzy point. And then, we will consider that some results respect effect of the upper sequence on the convergent fuzzy sequence, the bounded fuzzy sequence, and the Cauchy fuzzy sequence.
DEFF Research Database (Denmark)
Prasad, Ramjee; Ruggieri, Marina
2008-01-01
The paper focuses on the revolutionary changes that could characterise the future of networks. Those changes involve many aspects in the conceivement and exploitation of networks: architecture, services, technologies and modeling. The convergence of wired and wireless technologies along...... with the integration of system componennts and the convergence of services (e.g. communications and navigation) are only some of the elements that shape the perpsected mosaic. Authors delineate this vision, highlighting the presence of the space and stratospheric components and the related services as building block...
Some Improved Nonperturbative Bounds for Fermionic Expansions
Energy Technology Data Exchange (ETDEWEB)
Lohmann, Martin, E-mail: marlohmann@gmail.com [Universita di Roma Tre, Dipartimento di Matematica (Italy)
2016-06-15
We reconsider the Gram-Hadamard bound as it is used in constructive quantum field theory and many body physics to prove convergence of Fermionic perturbative expansions. Our approach uses a recursion for the amplitudes of the expansion, discovered in a model problem by Djokic (2013). It explains the standard way to bound the expansion from a new point of view, and for some of the amplitudes provides new bounds, which avoid the use of Fourier transform, and are therefore superior to the standard bounds for models like the cold interacting Fermi gas.
Discrete expansions of continuum wave functions
International Nuclear Information System (INIS)
Bang, J.; Ershov, S.N.; Gareev, F.A.; Kazacha, G.S.
1980-01-01
Different methods of expanding continuum wave functions in terms of discrete basis sets are discussed. The convergence properties of these expansions are investigated, both from a mathematical and a numerical point of view, for the case of potentials of Woods-Saxon and square well type. (orig.)
The Hubble series: convergence properties and redshift variables
International Nuclear Information System (INIS)
Cattoen, Celine; Visser, Matt
2007-01-01
In cosmography, cosmokinetics and cosmology, it is quite common to encounter physical quantities expanded as a Taylor series in the cosmological redshift z. Perhaps the most well-known exemplar of this phenomenon is the Hubble relation between distance and redshift. However, we now have considerable high-z data available; for instance, we have supernova data at least back to redshift z ∼ 1.75. This opens up the theoretical question as to whether or not the Hubble series (or more generally any series expansion based on the z-redshift) actually converges for large redshift. Based on a combination of mathematical and physical reasonings, we argue that the radius of convergence of any series expansion in z is less than or equal to 1, and that z-based expansions must break down for z > 1, corresponding to a universe less than half of its current size. Furthermore, we shall argue on theoretical grounds for the utility of an improved parametrization y = z/(1 + z). In terms of the y-redshift, we again argue that the radius of convergence of any series expansion in y is less than or equal to 1, so that y-based expansions are likely to be good all the way back to the big bang (y = 1), but that y-based expansions must break down for y < -1, now corresponding to a universe more than twice its current size
Directory of Open Access Journals (Sweden)
Coghetto Roland
2015-09-01
Full Text Available We are inspired by the work of Henri Cartan [16], Bourbaki [10] (TG. I Filtres and Claude Wagschal [34]. We define the base of filter, image filter, convergent filter bases, limit filter and the filter base of tails (fr: filtre des sections.
Branca, Mario
2013-01-01
Why does a lens magnify? Why does it shrink objects? Why does this happen? The activities that we propose here are useful in helping us to understand how lenses work, and they show that the same lens can have different magnification capabilities. A converging lens can also act as a diverging lens. (Contains 4 figures.)
Language Convergence Infrastructure
V. Zaytsev (Vadim); J.M. Fernandes; R. Lämmel (Ralf); J.M.W. Visser (Joost); J. Saraiva
2011-01-01
htmlabstractThe process of grammar convergence involves grammar extraction and transformation for structural equivalence and contains a range of technical challenges. These need to be addressed in order for the method to deliver useful results. The paper describes a DSL and the infrastructure behind
Kolodzy, Janet; Grant, August E.; DeMars, Tony R.; Wilkinson, Jeffrey S.
2014-01-01
The emergence of the Internet, social media, and digital technologies in the twenty-first century accelerated an evolution in journalism and communication that fit under the broad term of convergence. That evolution changed the relationship between news producers and consumers. It broke down the geographical boundaries in defining our communities,…
Directory of Open Access Journals (Sweden)
Pedro Luis Scattaregi
2009-10-01
Full Text Available OBJETIVO: avaliar as possíveis alterações e a estabilidade dentária e esquelética no sentido transversal, bem como as possíveis alterações verticais da face (AFAI, produzidas pela Expansão Rápida da Maxila Assistida Cirurgicamente (ERMAC. MÉTODOS: a amostra selecionada para este estudo retrospectivo foi composta por 60 telerradiografias em norma frontal, de 15 pacientes, sendo 6 do gênero masculino e 9 do gênero feminino, com média de idades de 23 anos e 3 meses. O disjuntor Hyrax foi instalado e o procedimento cirúrgico adotado envolveu a separação da sutura palatina mediana e não-abordagem da sutura pterigomaxilar. A ativação foi realizada do terceiro dias após a cirurgia até o término da expansão, determinada por critérios clínicos. Todos os pacientes foram radiografados nas fases pré-expansão (T1; pós-expansão imediata (T2; 3 meses pós-expansão, com o próprio disjuntor como contenção (T3; e 6 meses pós-expansão, com a placa removível de acrílico como contenção (T4. Medidas lineares foram obtidas a partir dos traçados cefalométricos gerados por um programa computadorizado (Radiocef Studio 2 e analisadas estatisticamente pelos testes de variância (ANOVA e Tukey ao nível de 5% de significância. RESULTADOS E CONCLUSÕES: concluiu-se que a ERMAC produziu aumentos estatisticamente significativos da cavidade nasal, da largura maxilar e da distância intermolares superiores, de T1 para T2, os quais se mantiveram em T3 e T4. A largura facial e as distâncias intermolares inferiores não apresentaram alterações após a ERMAC. Avaliando o comportamento vertical da face, notou-se um aumento da AFAI nas fases T1 para T2, que diminuiu após a contenção de 3 meses (T3 e permaneceu estável em T4, embora aumentada se comparada com T1.AIM: This study evaluated the stability of the dental and skeletal changes produced by the Surgically Assisted Rapid Maxillary Expansion (SARME in transversal and vertical
Asymptotic expansions for high-contrast linear elasticity
Poveda, Leonardo A.; Huepo, Sebastian; Calo, Victor M.; Galvis, Juan
2015-01-01
We study linear elasticity problems with high contrast in the coefficients using asymptotic limits recently introduced. We derive an asymptotic expansion to solve heterogeneous elasticity problems in terms of the contrast in the coefficients. We study the convergence of the expansion in the H1 norm. © 2015 Elsevier B.V.
Asymptotic expansions for high-contrast linear elasticity
Poveda, Leonardo A.
2015-03-01
We study linear elasticity problems with high contrast in the coefficients using asymptotic limits recently introduced. We derive an asymptotic expansion to solve heterogeneous elasticity problems in terms of the contrast in the coefficients. We study the convergence of the expansion in the H1 norm. © 2015 Elsevier B.V.
Series expansion of two-dimensional fields produced by iron-core magnets
International Nuclear Information System (INIS)
Satoh, Kotaro.
1997-02-01
This paper discusses the validity of a series expansion of two-dimensional magnetic fields with harmonic functions, and suggests that the series may not converge outside of the pole gap. It also points out that this difficulty may appear due to a slow convergence of the series near to the pole edge, even within the convergent area. (author)
Summable series and convergence factors
Moore, Charles N
1938-01-01
Fairly early in the development of the theory of summability of divergent series, the concept of convergence factors was recognized as of fundamental importance in the subject. One of the pioneers in this field was C. N. Moore, the author of the book under review.... Moore classifies convergence factors into two types. In type I he places the factors which have only the property that they preserve convergence for a convergent series or produce convergence for a summable series. In type II he places the factors which not only maintain or produce convergence but have the additional property that
Partial sums of arithmetical functions with absolutely convergent ...
Indian Academy of Sciences (India)
For an arithmetical function f with absolutely convergent Ramanujan expansion, we derive an asymptotic formula for the ∑ n ≤ N f(n)$ with explicit error term. As a corollary we obtain new results about sum-of-divisors functions and Jordan's totient functions.
Directory of Open Access Journals (Sweden)
Xueling Chen
Full Text Available The aim of this study was to evaluate the morphological changes of upper airway after protraction headgear and rapid maxillary expansion (PE treatment in growing patients with Class III malocclusion and maxillary skeletal deficiency compared with untreated Class III patients by cone-beam computed tomography (CBCT.Thirty growing patients who have completed PE therapy were included in PE group. The control group (n = 30 was selected from the growing untreated patients with the same diagnosis. The CBCT scans of the pre-treatment (T1 and post-treatment (T2 of PE group and the control group were collected. Reconstruction and registration of the 3D models of T1 and T2 were completed. By comparing the data obtained from T1, T2 and control group, the morphological changes of the upper airway during the PE treatment were evaluated.Comparing with the data from T1 group, the subspinale (A of maxilla and the upper incisor (UI of the T2 group were moved in the anterior direction. The gnathion (Gn of mandible was moved in the posterior-inferior direction. The displacement of the hyoid bone as well as the length and width of dental arch showed significant difference. The volume and mean cross-sectional area of nasopharynx, velopharynx and glossopharynx region showed significant difference. The largest anteroposterior/the largest lateral (AP/LR ratios of the velopharynx and glossopharynx were increased, but the AP/LR ratio of the hypopharynx was decreased. In addition, the length and width of the maxillary dental arch, the displacement of the hyoid bone, the volume of nasopharynx and velopharynx, and the AP/LR ratio of the hypopharynx and velopharynx showed significant difference between the data from control and T2 group.The PE treatment of Class III malocclusion with maxillary skeletal hypoplasia leads to a significant increase in the volume of nasopharynx and velopharynx.
DEFF Research Database (Denmark)
Kjeldsen, Lars Peter; Kjærgaard, Hanne Wacher
networks are still more prominently expected by students. Against this backdrop, an action research project has worked with the definition and testing of the hypothesized constituents of the Convergent Learning Space and how it challenges our traditional conceptions of learning spaces. The article...... describes this pilot study involving teachers in conscious, documented reflection on methods, approaches, and procedures conducive to learning processes in this new learning space. As a perspective, the article briefly outlines an intervention study aimed at investigating how students benefit from......The concept of the Convergent Learning Space has been hypothesized and explored in an ongoing action research project carried out at undergraduate level in select bachelor programs at a Danish University College, where classrooms are technology rich and students bring their own devices. The changes...
The Convergent Learning Space:
DEFF Research Database (Denmark)
Kjærgaard, Hanne Wacher; Kjeldsen, Lars Peter; Asmussen, Jørgen Bering
is described as well as the theoretical construct and hypotheses surrounding the emergence of the concept in technology-rich classrooms, where students bring their own devices and involve their personal learning spaces and networks. The need for new ways of approaching concepts like choice, learning resources......This paper describes the concept of “The Convergent Learning Space” as it is being explored in an ongoing action research project carried out at undergraduate level in select bachelor programs at a Danish University College. The background nature, design, and beginning of this work in progress......, trajectories of participation etc. calls for new action and new pedagogies by teachers in order to secure alignment between students’ worlds and expectations and aims and plans of the teacher. Action research methods are being used to define and test the constituents and variables of the convergent learning...
Simpson, Seamus
2015-01-01
The Broadcasting, Information Technology and Telecommunications sectors have in recent years been the subject of notable transformation, one important feature of which is their coming closer together in a number of ways - it is now commonplace to speak of a new hybrid sector, Information and Communications Technologies (ICTs). This convergence is of considerable interest to policy-makers in industry and government at the national and international level, as well as the academic community and,...
Convergence semigroup categories
Directory of Open Access Journals (Sweden)
Gary Richardson
2013-09-01
Full Text Available Properties of the category consisting of all objects of the form (X, S, λ are investigated, where X is a convergence space, S is a commutative semigroup, and λ: X × S → X is a continuous action. A “generalized quotient” of each object is defined without making the usual assumption that for each fixed g ∈ S, λ(., g : X → X is an injection.
Multiplier convergent series and uniform convergence of mapping ...
Indian Academy of Sciences (India)
MS received 14 April 2011; revised 17 November 2012. Abstract. In this paper, we introduce the frame property of complex sequence sets and study the uniform convergence of nonlinear mapping series in β-dual of spaces consisting of multiplier convergent series. Keywords. Multiplier convergent series; mapping series. 1.
Directory of Open Access Journals (Sweden)
Moara De Rossi
2010-06-01
Full Text Available INTRODUÇÃO: os aparelhos expansores maxilares com cobertura oclusal têm sido sugeridos para controlar o aumento na dimensão vertical da face após a expansão rápida da maxila, porém ainda não há um consenso na literatura sobre seus reais efeitos. OBJETIVO: o objetivo deste trabalho foi avaliar as alterações cefalométricas verticais e anteroposteriores associadas à expansão da maxila realizada com o aparelho expansor com cobertura oclusal. MÉTODOS: a amostra foi composta por 25 crianças, de ambos os gêneros, com idades entre 6 e 10 anos, portadoras de mordida cruzada posterior esquelética. Após a expansão maxilar, o próprio aparelho expansor foi utilizado como contenção fixa. Foram analisadas telerradiografias em norma lateral tomadas antes do início do tratamento e após a remoção do aparelho expansor. CONCLUSÃO: com base nos resultados, pôde-se concluir que o uso do aparelho expansor com cobertura oclusal não alterou significativamente as medidas cefalométricas verticais e anteroposteriores das crianças.INTRODUCTION: Bonded rapid maxillary expansion appliances have been suggested to control increases in the vertical dimension of the face after rapid maxillary expansion but there is still no consensus in the literature concerning its actual effectiveness. OBJECTIVE: The purpose of this study was to evaluate the vertical and anteroposterior cephalometric changes associated with maxillary expansion performed using bonded rapid maxillary expansion appliances. METHODS: The sample consisted of 25 children of both genders, aged between 6 and 10 years old, with skeletal posterior crossbite. After maxillary expansion, the expansion appliance itself was used for fixed retention. Were analyzed lateral teleradiographs taken prior to treatment onset and after removal of the expansion appliance. CONCLUSION: Based on the results, it can be concluded that the use of bonded rapid maxillary expansion appliance did not significantly
Convergence semigroup actions: generalized quotients
Directory of Open Access Journals (Sweden)
H. Boustique
2009-10-01
Full Text Available Continuous actions of a convergence semigroup are investigated in the category of convergence spaces. Invariance properties of actions as well as properties of a generalized quotient space are presented
IT Convergence and Security 2012
Chung, Kyung-Yong
2013-01-01
The proceedings approaches the subject matter with problems in technical convergence and convergences of security technology. This approach is new because we look at new issues that arise from techniques converging. The general scope of the proceedings content is convergence security and the latest information technology. The intended readership are societies, enterprises, and research institutes, and intended content level is mid- to highly educated personals. The most important features and benefits of the proceedings are the introduction of the most recent information technology and its related ideas, applications and problems related to technology convergence, and its case studies and finally an introduction of converging existing security techniques through convergence security. Overall, through the proceedings, authors will be able to understand the most state of the art information strategies and technologies of convergence security.
Dimensioning Method for Conversational Video Applications in Wireless Convergent Networks
Directory of Open Access Journals (Sweden)
Raquel Perez Leal
2007-12-01
Full Text Available New convergent services are becoming possible, thanks to the expansion of IP networks based on the availability of innovative advanced coding formats such as H.264, which reduce network bandwidth requirements providing good video quality, and the rapid growth in the supply of dual-mode WiFi cellular terminals. This paper provides, first, a comprehensive subject overview as several technologies are involved, such as medium access protocol in IEEE802.11, H.264 advanced video coding standards, and conversational application characterization and recommendations. Second, the paper presents a new and simple dimensioning model of conversational video over wireless LAN. WLAN is addressed under the optimal network throughput and the perspective of video quality. The maximum number of simultaneous users resulting from throughput is limited by the collisions taking place in the shared medium with the statistical contention protocol. The video quality is conditioned by the packet loss in the contention protocol. Both approaches are analyzed within the scope of the advanced video codecs used in conversational video over IP, to conclude that conversational video dimensioning based on network throughput is not enough to ensure a satisfactory user experience, and video quality has to be taken also into account. Finally, the proposed model has been applied to a real-office scenario.
Dimensioning Method for Conversational Video Applications in Wireless Convergent Networks
Directory of Open Access Journals (Sweden)
Alonso JoséI
2008-01-01
Full Text Available Abstract New convergent services are becoming possible, thanks to the expansion of IP networks based on the availability of innovative advanced coding formats such as H.264, which reduce network bandwidth requirements providing good video quality, and the rapid growth in the supply of dual-mode WiFi cellular terminals. This paper provides, first, a comprehensive subject overview as several technologies are involved, such as medium access protocol in IEEE802.11, H.264 advanced video coding standards, and conversational application characterization and recommendations. Second, the paper presents a new and simple dimensioning model of conversational video over wireless LAN. WLAN is addressed under the optimal network throughput and the perspective of video quality. The maximum number of simultaneous users resulting from throughput is limited by the collisions taking place in the shared medium with the statistical contention protocol. The video quality is conditioned by the packet loss in the contention protocol. Both approaches are analyzed within the scope of the advanced video codecs used in conversational video over IP, to conclude that conversational video dimensioning based on network throughput is not enough to ensure a satisfactory user experience, and video quality has to be taken also into account. Finally, the proposed model has been applied to a real-office scenario.
Radial expansion and multifragmentation
International Nuclear Information System (INIS)
Angelique, J.C.; Bizard, G.; Bougault, R.; Brou, R.; Buta, A.; Colin, J.; Cussol, D.; Durand, D.; Kerambrun, A.; Le Brun, C.; Lecolley, J.F.; Lopez, O.; Louvel, M.; Meslin, C.; Nakagawa, T.; Patry, J.P.; Peter, J.; Popescu, R.; Regimbart, R.; Steckmeyer, J.C.; Tamain, B.; Vient, E.; Yuasa-Nakagawa, K.; Wieloch, A.
1998-01-01
The light systems 36 Ar + 27 Al and 64 Zn + nat Ti were measured at several bombarding energies between ∼ 35 and 95 MeV/nucleon. It was found that the predominant part of the cross section is due to binary collisions. In this paper the focus is placed on the properties of the quasi-projectile nuclei. In the central collisions the excitation energies of the quasi-projectile reach values exceeding largely 10 MeV/nucleon. The slope of the high energy part of the distribution can give only an upper limit of the apparent temperature (the average temperature along the decay chain). The highly excited quasi-projectile may get rapidly fragmented rather than sequentially. The heavy fragments are excited and can emit light particles (n, p, d, t, 3 He, α,...) what perturbs additionally the spectrum of these particles. Concerning the expansion energy, one can determine the average kinetic energies of the product (in the quasi-projectile-framework) and compare with simulation values. To fit the experimental data an additional radial expansion energy is to be considered. The average expansion energy depends slightly on the impact parameter but it increases with E * / A, ranging from 0.4 to 1,2 MeV/nucleon for an excitation energy increasing from 7 to 10.5 MeV/nucleon. This collective radial energy seems to be independent of the fragment mass, what is possibly valid for the case of larger quasi-projectile masses. The origin of the expansion is to be determined. It may be due to a compression in the interaction zone at the initial stage of the collision, which propagates in the quasi-projectile and quasi-target, or else, may be due, simply, to the increase of thermal energy leading to a rapid fragment emission. The sequential de-excitation calculation overestimates light particle emission and consequently heavy residues, particularly, at higher excitation energies. This disagreement indicates that a sequential process can not account for the di-excitation of very hot nuclei
Derivative expansion and renormalisation group flows
Litim, Daniel F
2001-01-01
We study the convergence of the derivative expansion for flow equations. The convergence strongly depends on the choice for the infrared regularisation. Based on the structure of the flow, we explain why optimised regulators lead to better physical predictions. This is applied to O(N)-symmetric real scalar field theories in 3d, where critical exponents are computed for all N. In comparison to the sharp cut-off regulator, an optimised flow improves the leading order result up to 10%. An analogous reasoning is employed for a proper time renormalisation group. We compare our results with those obtained by other methods.
Local Convergence and Radius of Convergence for Modified Newton Method
Directory of Open Access Journals (Sweden)
Măruşter Ştefan
2017-12-01
Full Text Available We investigate the local convergence of modified Newton method, i.e., the classical Newton method in which the derivative is periodically re-evaluated. Based on the convergence properties of Picard iteration for demicontractive mappings, we give an algorithm to estimate the local radius of convergence for considered method. Numerical experiments show that the proposed algorithm gives estimated radii which are very close to or even equal with the best ones.
Towards finite density QCD with Taylor expansions
International Nuclear Information System (INIS)
Karsch, F.; Schaefer, B.-J.; Wagner, M.; Wambach, J.
2011-01-01
Convergence properties of Taylor expansions of observables, which are also used in lattice QCD calculations at non-zero chemical potential, are analyzed in an effective N f =2+1 flavor Polyakov quark-meson model. A recently developed algorithmic technique allows the calculation of higher-order Taylor expansion coefficients in functional approaches. This novel technique is for the first time applied to an effective N f =2+1 flavor Polyakov quark-meson model and the findings are compared with the full model solution at finite densities. The results are used to discuss prospects for locating the QCD phase boundary and a possible critical endpoint in the phase diagram.
Medialogy - convergence and transdisciplinarity
DEFF Research Database (Denmark)
Nordahl, Rolf
2007-01-01
Art and design have many qualities which intuitively by society are appreciated. But on daily basis they are also assessed and evaluated. Some communities also share common understandings that norms, standards, conventions evolve, both from artistic desire as well as from more physical needs...... for changes in society, developments in taste etc. However, it certainly seems fair to say, that available technology makes a great difference to the development of any art form or practice. With the up rise of new educations such as Medialogy, new aspects of convergence and different forms...... of interdisciplinarity and transdisciplinarity is a pre-requisite for both researchers and students. In this talk we will demonstrate our approach through concrete examples of student productions and projects. We will also display the pedagogical method (problem based learning), that enables students to bridge gaps...
On a Convergence of Rational Approximations by the Modified Fourier Basis
Directory of Open Access Journals (Sweden)
Tigran Bakaryan
2017-12-01
Full Text Available We continue investigations of the modified-trigonometric-rational approximations that arise while accelerating the convergence of the modified Fourier expansions by means of rational corrections. Previously, we investigated the pointwise convergence of the rational approximations away from the endpoints and the $L_2$-convergence on the entire interval. Here, we study the convergence at the endpoints and derive the exact constants for the main terms of asymptotic errors. We show that the Fourier-Pade approximations are much more accurate in all frameworks than the modified expansions for sufficiently smooth functions. Moreover, we consider a simplified version of the rational approximations and explore the optimal values of parameters that lead to better accuracy in the framework of the $L_2$-error. Numerical experiments perform comparisons of the rational approximations with the modified Fourier expansions.
Molecular mechanisms involved in convergent crop domestication.
Lenser, Teresa; Theißen, Günter
2013-12-01
Domestication has helped to understand evolution. We argue that, vice versa, novel insights into evolutionary principles could provide deeper insights into domestication. Molecular analyses have demonstrated that convergent phenotypic evolution is often based on molecular changes in orthologous genes or pathways. Recent studies have revealed that during plant domestication the causal mutations for convergent changes in key traits are likely to be located in particular genes. These insights may contribute to defining candidate genes for genetic improvement during the domestication of new plant species. Such efforts may help to increase the range of arable crops available, thus increasing crop biodiversity and food security to help meet the predicted demands of the continually growing global population under rapidly changing environmental conditions. Copyright © 2013 Elsevier Ltd. All rights reserved.
Convergence and analytic properties of manifestly finite perturbation theory
International Nuclear Information System (INIS)
Mtingwa, S.K.
1979-01-01
The author discusses more carefully the ultraviolet convergence properties of Feynman diagrams in recently proposed manifestly finite perturbation expansions. Speccifically, he refines one of the constraints on the γ's-the noncanonical dimensions-such that, when satisfied, any general product-type interaction of massive scalar, fermion and vector fields yields finite perturbation expansions requiring no conventional renormalization procedure. Moreover, the analytic properties of the Feynman integrals in the theory are discussed and concluded with remarks on the necessity of a modified Kaellen-Lehmann representation
Convergent systems vs. incremental stability
Rüffer, B.S.; Wouw, van de N.; Mueller, M.
2013-01-01
Two similar stability notions are considered; one is the long established notion of convergent systems, the other is the younger notion of incremental stability. Both notions require that any two solutions of a system converge to each other. Yet these stability concepts are different, in the sense
Giant lobelias exemplify convergent evolution
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Givnish Thomas J
2010-01-01
Full Text Available Abstract Giant lobeliads on tropical mountains in East Africa and Hawaii have highly unusual, giant-rosette growth forms that appear to be convergent on each other and on those of several independently evolved groups of Asteraceae and other families. A recent phylogenetic analysis by Antonelli, based on sequencing the widest selection of lobeliads to date, raises doubts about this paradigmatic example of convergent evolution. Here I address the kinds of evidence needed to test for convergent evolution and argue that the analysis by Antonelli fails on four points. Antonelli's analysis makes several important contributions to our understanding of lobeliad evolution and geographic spread, but his claim regarding convergence appears to be invalid. Giant lobeliads in Hawaii and Africa represent paradigmatic examples of convergent evolution.
Convergent WKB Series--How Can It be ?
International Nuclear Information System (INIS)
Ezawa, Hiroshi; Nakamura, Toru; Watanabe, Keiji
2008-01-01
Schroedinger equation for a polynomial potential with the highest order term having an even power and a positive coefficient is solved for high eigenvalues E n in two different ways after Liouville transformation, (a) converting the differential equation into integral equation and solving it iteratively and (b) by the WKB method. While the series solution in powers of 1/√(E n ) from (b) is known to diverge, we show that the one from (a) converges. We show then that asymptotic re-expansion of the convergent series from (a) agrees with the divergent series from (b). Actually, we have been able to show the agreement only up to order (1/√(E n )) 5 , but we believe that it holds to all orders. If this is true, the divergent WKB series can be reorganized into a convergent series, which is in fact obtained by the method of iteration (a)
Directory of Open Access Journals (Sweden)
R. Siriram
2012-01-01
Full Text Available
ENGLISH ABSTRACT: Technology is a catalyst for competitive advantage. However, it is how technology is used that leads to a firm’s improved performance. In this article, an investigative framework is constructed to understand better what strategically drives new technology adoption. The strategic drivers include technology and business strategy alignment, better technology planning and selection of new technologies, the effects on a firm’s culture and climate, links to a firm’s organisational and environmental evolution, and benefits through convergence and collaboration. Using an investigative framework, it is shown how the strategic drivers link to improve a firm’s performance, producing competitive advantage. The investigative framework is tested using structural equation modelling. Various hypotheses are formed, and recommendations for further research are made.
AFRIKAANSE OPSOMMING: Tegnologie is ‘n katalisator vir mededingende voordeel. Dit is egter hoe tegnologie aangewend word wat aanleiding gee tot ‘n onderneming se verbeterde prestasie. In hierdie artikel word ‘n ondersoekende raamwerk gekonstrueer om insig te kry in dit wat die aanvaarding van nuwe tegnologie strategies dryf. Die strategiese dryfvere sluit in die belyning van tegnologie en ondernemingstrategie, beter tegnologiebeplanning en seleksie van nuwe tegnologieë, die effek op ‘n onderneming se kultuur en klimaat, koppeling na ‘n onderneming se organisatoriese en omgewingsevolusie, en voordele verkry deur konvergensie en samewerking. Deur ‘n ondersoekende raamwerk te gebruik, word daar getoon dat die strategiese dryfvere koppel om ‘n onderneming se prestasie te verbeter en sodoende ‘n mededingende voordeel te skep. Die raamwerk word getoets en hipoteses geformuleer waarna aanbevelings oor verdere navorsing aan die hand gedoen word.
Directory of Open Access Journals (Sweden)
Miguel Torrejo˜n-Velardiez
2010-03-01
Full Text Available This article uses the Valencian Community (Spain as a case study to analyse, in terms of GDP per person, the convergence of regions of intermediate development with the most advanced ones within the European Union. The obstacles hindering this convergence and the paths the convergence takes are shown not only in the context of a growing interdependence in the world economy but also of European integration. The study clearly demonstrates how convergence only comes about as a result of the creation of employment, while the gap in productivity is getting ever wider. The explanation fundamentally stems from the lack of convergence of the production structure with the more advanced activities which predominate in the most developed regions. With the arrival of the economic crisis from 2007, a reversal has occurred of the process of convergence that had taken place during the previous phase of expansion.
The Convergence in Spatial Tasks
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Vladimir P. Kulagin
2013-01-01
Full Text Available The article reveals the problem of convergence of direct and inverse problems in Earth Sciences, describes the features and application of these problems, discloses analytical features of direct and inverse problems. The convergence criteria and conditions for convergence were presented. This work is supported by the Grant of the Government of the Russian Federation for support of scientific research, implemented under the supervision of leading scientists in Russian institutions of higher education in the field "Space Research and Technologies" in 2011–2013.
Directory of Open Access Journals (Sweden)
Rodrigo Rezende de Albuquerque
2006-04-01
Full Text Available OBJETIVO: a proposta deste estudo foi determinar se a previsibilidade de sucesso da disjunção palatina está correlacionada a algum evento de maturidade esquelética que determine o final do crescimento geral do organismo. METODOLOGIA: utilizando o conhecimento dos estágios de maturação esquelética visualizados por radiografia de mão e punho e registrados em um gráfico do surto de crescimento puberal, foram avaliados dezenove pacientes de ambos os gêneros, com idades variando de dez anos e três meses a vinte e oito anos e quatro meses, supervisionados por análises clínicas e radiográficas específicas antes e após o procedimento de disjunção palatina. RESULTADO E CONCLUSÃO: pode-se afirmar que não foi possível determinar a previsibilidade de sucesso da disjunção palatina quando esta foi correlacionada com a ossificação total do osso rádio.AIM: to evaluate the possibility of rapid maxillary expansion in patients who have reached the decisive event of facial growth ending (total fusion of the radius. METHODS: the study was held using esqueletal maturation data from hand and wrist x-ray plotted in a puberal growth spurt graph from nineteen patients of both genders at ages ranging from ten years and three months to twenty-eight years and four months surveilled by specific clinical and radiographic analysis before and after the rapid maxillary expansion procedure. RESULTS AND CONCLUSION: it could be concluded that it was not possible to establish a successful correlation between total fusion of radius with rapid maxillary expansion.
Irreversible Local Markov Chains with Rapid Convergence towards Equilibrium
Kapfer, Sebastian C.; Krauth, Werner
2017-12-01
We study the continuous one-dimensional hard-sphere model and present irreversible local Markov chains that mix on faster time scales than the reversible heat bath or Metropolis algorithms. The mixing time scales appear to fall into two distinct universality classes, both faster than for reversible local Markov chains. The event-chain algorithm, the infinitesimal limit of one of these Markov chains, belongs to the class presenting the fastest decay. For the lattice-gas limit of the hard-sphere model, reversible local Markov chains correspond to the symmetric simple exclusion process (SEP) with periodic boundary conditions. The two universality classes for irreversible Markov chains are realized by the totally asymmetric SEP (TASEP), and by a faster variant (lifted TASEP) that we propose here. We discuss how our irreversible hard-sphere Markov chains generalize to arbitrary repulsive pair interactions and carry over to higher dimensions through the concept of lifted Markov chains and the recently introduced factorized Metropolis acceptance rule.
From Fourier Series to Rapidly Convergent Series for Zeta(3)
DEFF Research Database (Denmark)
Scheufens, Ernst E
2011-01-01
The article presents a mathematical study which investigates the exact values of the Riemann zeta (ζ) function. It states that exact values can be determined from Fourier series for periodic versions of even power functions. It notes that using power series for logarithmic functions on this such ......The article presents a mathematical study which investigates the exact values of the Riemann zeta (ζ) function. It states that exact values can be determined from Fourier series for periodic versions of even power functions. It notes that using power series for logarithmic functions...
Nonperturbative path integral expansion II
International Nuclear Information System (INIS)
Kaiser, H.J.
1976-05-01
The Feynman path integral representation of the 2-point function for a self-interacting Bose field is investigated using an expansion ('Path Integral Expansion', PIE) of the exponential of the kinetic term of the Lagrangian. This leads to a series - illustrated by a graph scheme - involving successively a coupling of more and more points of the lattice space commonly employed in the evaluation of path integrals. The values of the individual PIE graphs depend of course on the lattice constant. Two methods - Pade approximation and Borel-type extrapolation - are proposed to extract information about the continuum limit from a finite-order PIE. A more flexible PIE is possible by expanding besides the kinetic term a suitably chosen part of the interaction term too. In particular, if the co-expanded part is a mass term the calculation becomes only slightly more complicated than in the original formulation and the appearance of the graph scheme is unchanged. A significant reduction of the number of graphs and an improvement of the convergence of the PIE can be achieved by performing certain sums over an infinity of graph elements. (author)
Negative thermal expansion materials
International Nuclear Information System (INIS)
Evans, J.S.O.
1997-01-01
The recent discovery of negative thermal expansion over an unprecedented temperature range in ZrW 2 O 8 (which contracts continuously on warming from below 2 K to above 1000 K) has stimulated considerable interest in this unusual phenomenon. Negative and low thermal expansion materials have a number of important potential uses in ceramic, optical and electronic applications. We have now found negative thermal expansion in a large new family of materials with the general formula A 2 (MO 4 ) 3 . Chemical substitution dramatically influences the thermal expansion properties of these materials allowing the production of ceramics with negative, positive or zero coefficients of thermal expansion, with the potential to control other important materials properties such as refractive index and dielectric constant. The mechanism of negative thermal expansion and the phase transitions exhibited by this important new class of low-expansion materials will be discussed. (orig.)
Ecomorphological convergence in planktivorous surgeonfishes
Friedman, S. T.; Price, S. A.; Hoey, Andrew; Wainwright, P. C.
2016-01-01
two diet regimes: zooplanktivores and nonzooplanktivorous grazers. Accounting for phylogenetic relationships, the best-fitting model indicates that zooplanktivorous species are converging on a separate adaptive peak from their grazing relatives
Weak entropy inequalities and entropic convergence
Institute of Scientific and Technical Information of China (English)
2008-01-01
A criterion for algebraic convergence of the entropy is presented and an algebraic convergence result for the entropy of an exclusion process is improved. A weak entropy inequality is considered and its relationship to entropic convergence is discussed.
Searching for convergence and its causes – an industry perspective
Inklaar, Robert; Jorgenson, Dale W.; Fukao, Kyoji; Timmer, Marcel P.
2016-01-01
The past 20 years has been a period of rapid growth in emerging economies, leading to convergence in income and productivity levels. Less is known about the industry origins of this development, a gap this chapter aims to fill. For 30 industries in 40 economies, I estimate industry relative
Convergent surface water distributions in U.S. cities
M.K. Steele; J.B. Heffernan; N. Bettez; J. Cavender-Bares; P.M. Groffman; J.M. Grove; S. Hall; S.E. Hobbie; K. Larson; J.L. Morse; C. Neill; K.C. Nelson; J. O' Neil-Dunne; L. Ogden; D.E. Pataki; C. Polsky; R. Roy Chowdhury
2014-01-01
Earth's surface is rapidly urbanizing, resulting in dramatic changes in the abundance, distribution and character of surface water features in urban landscapes. However, the scope and consequences of surface water redistribution at broad spatial scales are not well understood. We hypothesized that urbanization would lead to convergent surface water abundance and...
Directory of Open Access Journals (Sweden)
Rogério Christofoletti
2008-12-01
Full Text Available Três idéias já seriam suficientes para que a leitura de “Culturada Convergência”, de Henry Jenkins, interessasse a jornalistas epesquisadores da área: a convergência midiática como um processo cultural; o fortalecimento de uma economia afetiva que orienta consumidores de bens simbólicos e criadores midiáticos; a expansão de formas narrativas transmidiáticas.
Globalization and Contemporary Fertility Convergence.
Hendi, Arun S
2017-09-01
The rise of the global network of nation-states has precipitated social transformations throughout the world. This article examines the role of political and economic globalization in driving fertility convergence across countries between 1965 and 2009. While past research has typically conceptualized fertility change as a country-level process, this study instead employs a theoretical and methodological framework that examines differences in fertility between pairs of countries over time. Convergence in fertility between pairs of countries is hypothesized to result from increased cross-country connectedness and cross-national transmission of fertility-related schemas. I investigate the impact of various cross-country ties, including ties through bilateral trade, intergovernmental organizations, and regional trade blocs, on fertility convergence. I find that globalization acts as a form of social interaction to produce fertility convergence. There is significant heterogeneity in the effects of different cross-country ties. In particular, trade with rich model countries, joint participation in the UN and UNESCO, and joining a free trade agreement all contribute to fertility convergence between countries. Whereas the prevailing focus in fertility research has been on factors producing fertility declines, this analysis highlights specific mechanisms-trade and connectedness through organizations-leading to greater similarity in fertility across countries. Globalization is a process that propels the spread of culturally laden goods and schemas impinging on fertility, which in turn produces fertility convergence.
Choice of single-particle potential and the convergence of the effective interaction
International Nuclear Information System (INIS)
Hjorth-Jensen, M.; Osnes, E.; Muether, H.; Schmid, K.W.
1990-02-01
The convergence of the expansion for the effective interaction is studied considering as example the shell model for the nuclei 18 O and 18 F. In this work the effective interaction is computed through third order in the Brueckner G matrix, using both a harmonic-oscillator (HO) basis and a Brueckner-Hartree-Fock (BHF) basis. The significant differences in the convergence behavior of the effective interaction in these two cases are reported. The results indicate that the choice of the BHF single-particle potential facilitates the convergence of the effective interaction in low-orders of the expansion, whereas the HO results exhibit a non-convergent behavior. The implications for the HO approach are discussed. All calculations have been performed considering a modern version of the Bonn one-boson-exchange potential for the nucleon-nucleon interaction. 23 refs., 4 figs., 2 tabs
Approximation by some combinations of Poisson integrals for Hermite and Laguerre expansions
Directory of Open Access Journals (Sweden)
Grażyna Krech
2013-02-01
Full Text Available The aim of this paper is the study of a rate of convergence of some combinations of Poisson integrals for Hermite and Laguerre expansions. We are able to achieve faster convergence for our modified operators over the Poisson integrals. We prove also the Voronovskaya type theorem for these new operators.
ZONAL TOROIDAL HARMONIC EXPANSIONS OF EXTERNAL GRAVITATIONAL FIELDS FOR RING-LIKE OBJECTS
Energy Technology Data Exchange (ETDEWEB)
Fukushima, Toshio, E-mail: Toshio.Fukushima@nao.ac.jp [National Astronomical Observatory, Ohsawa, Mitaka, Tokyo 181-8588 (Japan)
2016-08-01
We present an expression of the external gravitational field of a general ring-like object with axial and plane symmetries such as oval toroids or annular disks with an arbitrary density distribution. The main term is the gravitational field of a uniform, infinitely thin ring representing the limit of zero radial width and zero vertical height of the object. The additional term is derived from a zonal toroidal harmonic expansion of a general solution of Laplace’s equation outside the Brillouin toroid of the object. The special functions required are the point value and the first-order derivative of the zonal toroidal harmonics of the first kind, namely, the Legendre function of the first kind of half integer degree and an argument that is not less than unity. We developed a recursive method to compute them from two pairs of seed values explicitly expressed by some complete elliptic integrals. Numerical experiments show that appropriately truncated expansions converge rapidly outside the Brillouin toroid. The truncated expansion can be evaluated so efficiently that, for an oval toroid with an exponentially damping density profile, it is 3000–10,000 times faster than the two-dimensional numerical quadrature. A group of the Fortran 90 programs required in the new method and their sample outputs are available electronically.
Ring Expansion and Rearrangements of Rhodium(II) Azavinyl Carbenes
Selander, Nicklas; Worrell, Brady T.
2013-01-01
An efficient, regioselective and convergent method for the ring expansion and rearrangement of 1-sulfonyl-1,2,3-triazoles under rhodium(II)-catalyzed conditions is described. These denitrogenative reactions form substituted enaminone and olefin-based products, which in the former case can be further functionalized to unique products rendering the sulfonyl triazole traceless. PMID:23161725
Directory of Open Access Journals (Sweden)
Edmilsson Pedro Jorge
2011-02-01
Full Text Available A finalidade deste artigo é avaliar o efeito da expansão rápida da maxila (ERM na via aérea superior. Por intermédio de um caso clínico, será relatado como indivíduos com atresia da maxila e com comprometimento da função naso-respiratória podem beneficiar-se com a ERM. Para entender melhor as alterações morfológicas decorrentes do paciente com problemas respiratórios, deve-se conhecer a anatomia e a fisiologia do sistema respiratório. Entretanto, não se pode esquecer que o tratamento deste paciente é multidisciplinar, envolvendo o ortodontista, otorrinolaringologista e a fonoaudióloga.The aim of the present investigation is to evaluate the effect of rapid maxillary expansion (RME on the upper airway. A clinical case is presented to describe how patients with atresic maxilla and reduced naso-respiratory function can have benefits from rapid maxillary expansion. In order to better understand the morphological alterations present in patients with respiratory disorders, it is necessary to understand the respiratory system's anatomy and physiology. However, it is relevant to mention that this patient undergoes a multidisciplinary treatment, involving the orthodontist, the otorhinolaryngologist and the phonoaudiologist.
Trophic convergence drives morphological convergence in marine tetrapods.
Kelley, Neil P; Motani, Ryosuke
2015-01-01
Marine tetrapod clades (e.g. seals, whales) independently adapted to marine life through the Mesozoic and Caenozoic, and provide iconic examples of convergent evolution. Apparent morphological convergence is often explained as the result of adaptation to similar ecological niches. However, quantitative tests of this hypothesis are uncommon. We use dietary data to classify the feeding ecology of extant marine tetrapods and identify patterns in skull and tooth morphology that discriminate trophic groups across clades. Mapping these patterns onto phylogeny reveals coordinated evolutionary shifts in diet and morphology in different marine tetrapod lineages. Similarities in morphology between species with similar diets-even across large phylogenetic distances-are consistent with previous hypotheses that shared functional constraints drive convergent evolution in marine tetrapods.
Energy Technology Data Exchange (ETDEWEB)
Dzenus, M.; Hundhausen, W.; Jansing, W.
1979-10-15
This discourse recounts efforts put into the SNR-2 project; specifically the development of compensation devices. The various prototypes of these compensation devices are described and the state of development reviewed. The expansion joints were developed on the basis of specific design criteria whereby differentiation is made between expansion joints of small and large nominal diameter. Expansion joints for installation in the sodium-filled primary piping are equipped with safety bellows in addition to the actual working bellows.
Digital Convergence and Content Regulation
Directory of Open Access Journals (Sweden)
Michael John Starks
2014-12-01
Full Text Available Broadcasting, Press and Internet journalism systems of distribution are converging: the same infrastructure can deliver all three historically separate services. Reception devices mirror this: the Connected TV, the tablet and the smart phone overlap in their functionality. Service overlaps are evident too, with broadcasters providing online and on-demand services and newspapers developing electronic versions. Does this mean that media regulation policies must converge too?My argument is that they should, though only where historically different communications are now fulfilling a similar function, e.g. broadcaster online services and electronic versions of newspapers. Convergence requires a degree of harmonisation and, to this end, I advocate a review of UK broadcasting's 'due impartiality' requirement and of the UK's application of the public service concept. I also argue for independent self-regulation (rather than state-based regulation of non-public-service broadcasting journalism.
Directory of Open Access Journals (Sweden)
Rogério Christofoletti
2008-12-01
Full Text Available Três idéias já seriam suficientes para que a leitura de “Cultura da Convergência”, de Henry Jenkins, interessasse a jornalistas e pesquisadores da área: a convergência midiática como um processo cultural; o fortalecimento de uma economia afetiva que orienta consumidores de bens simbólicos e criadores midiáticos; a expansão de formas narrativas transmidiáticas.
Peruvian Higher Education: Expansions Amid Economic Crisis.
Post, David
1991-01-01
Development of the Peruvian university system is described, focusing on periods of rapid expansion. Enrollment declines in 1974-78 are analyzed in the context of the educational reform program of the military government. The 1983 new university law, following return to civilian government, and future prospects for higher education are discussed.…
The delta expansion in zero dimensions
International Nuclear Information System (INIS)
Cho, H.T.; Milton, K.A.; Pinsky, S.S.; Simmons, L.M. Jr.
1989-01-01
The recently introduced δ-expansion (or logarithmic-expansion) technique for obtaining nonperturbative information about quantum field theories is reviewed in the zero-dimensional context. There, it is easy to study questions of analytic continuation that arise in the construction of the Feynman rules that generate the δ series. It is found that for six- and higher-point Green's functions, a cancellation occurs among the most divergent terms, and that divergences that arise from summing over an infinite number of internal lines are illusory. The numerical accuracy is studied in some detail: The δ series converges inside a circle of radius one for positive bare mass squared, and diverges if the bare mass squared is negative, but in all cases, low-order Pade approximants are extremely accurate. These general features are expected to hold in higher dimensions, such as four
Convergence accommodation to convergence CA/C ratio: convergence versus divergence.
Simmons, Joshua M; Firth, Alison Y
2014-09-01
To determine whether the convergence accommodation to convergence (CA/C) ratio during divergence with base-in (BI) prisms is of a similar or different magnitude to that measured during convergence with base-out (BO) prisms. Eighteen participants with normal binocular single vision were recruited. The participants viewed a pseudo-Gaussian target, which consisted of a light emitting diode (LED) behind a diffusing screen at 40 cm. After 5 minutes of dark adaptation, the refractive status of the eye was measured without any prism using a Shin-Nippon SRW-5000 autorefractor. The participant held the selected prism (5Δ or 10Δ BO or BI, counterbalanced) in front of their right eye and obtained a single, fused image of the target while refractive measures were taken with each. A 30-second rest period was given between measurements. The mean age of the participants was 20.6±3.22 years. The mean CA/C ratios for the 5Δ BO, 10Δ BO, 5Δ BI, and 10Δ BI were 0.108 (±0.074) D/Δ, 0.110 (±0.056) D/Δ, 0.100 (±0.090) D/Δ, and 0.089 (±0.055) D/Δ, respectively. A 2-factor repeated measures ANOVA found that the CA/C ratio did not significantly change with differing levels of prism-induced convergence and divergence (p=0.649). Change in accommodation induced by manipulating vergence is similar whether convergence or divergence are induced. The CA/C ratio did not show any change with differing levels of prism-induced convergence and divergence.
Design of convergent switched systems
Berg, van den R.A.; Pogromsky, A.Y.; Leonov, G.A.; Rooda, J.E.; Pettersen, K.Y.; Gravdahl, J.T.; Nijmeijer, H.
2006-01-01
In this paper we deal with the problem of rendering hybrid/nonlinear systems into convergent closed-loop systems by means of a feedback law or switching rules. We illustrate our approach to this problem by means of two examples: the anti-windup design for a marginally stable system with input
Convergence Patterns in Latin America
DEFF Research Database (Denmark)
Quiroga, Paola Andrea Barrientos
characteristics, and external shocks in the region. I study three important phases, following Thorp (1998): from 1900 to 1930, the exporting phase, from 1931 to 1974, the industrialization phase, and from 1975 to 2007, the globalization phase. During the last two phases, I find strong evidence of convergence...
Convergence of a Catalan Series
Koshy, Thomas; Gao, Zhenguang
2012-01-01
This article studies the convergence of the infinite series of the reciprocals of the Catalan numbers. We extract the sum of the series as well as some related ones, illustrating the power of the calculus in the study of the Catalan numbers.
Digital Convergence and Content Regulation
Starks, Michael John
2014-01-01
abstractBroadcasting, Press and Internet journalism systems of distribution are converging: the same infrastructure can deliver all three historically separate services. Reception devices mirror this: the Connected TV, the tablet and the smart phone overlap in their functionality. Service overlaps
Convergence and migration among provinces.
Helliwell, J F
1996-04-01
"Have regional disparities in Canada changed over the past thirty years? This paper assesses the robustness of earlier findings of convergence in the levels and growth rates of provincial per capita GDP, and then estimates the extent to which interprovincial and international migration is being influenced by regional differences in incomes and employment." excerpt
Revisiting convergence: A research note.
Clark, Rob
2015-09-01
A number of recent studies show that income inequality is declining between countries. In this research note, I question the significance of this trend by examining the role of initial conditions in producing convergence. An important (but neglected) property of inequality dynamics is the tendency for extreme distributions to become more moderate. When income disparities are large, the subsequent trend is biased toward convergence. Conversely, when initial conditions approach parity, divergence becomes the more likely long-term outcome. I apply this principle to trends in GDP PC across 127 countries during the 1980-2010 period. Using counterfactual analysis, I manipulate the initial level of inequality in GDP PC while holding constant each country's observed growth rate during the sample period. I find that the growth dynamics of GDP PC produce either convergence or divergence based simply on the initial distribution of income. The point of transition occurs at a moderate level of inequality, whether using population weights (Gini=.365) or not (Gini=.377). I conclude that the recent convergence observed in GDP PC is primarily a function of large income gaps between countries and would not have materialized at more moderate levels of initial inequality. By contrast, an examination of the pre-1950 period reveals divergent growth patterns that are not sensitive to initial conditions. Copyright © 2015 Elsevier Inc. All rights reserved.
Industrial Evolution Through Complementary Convergence
DEFF Research Database (Denmark)
Frøslev Christensen, Jens
2011-01-01
The article addresses the dynamics through which product markets become derailed from early product life cycle (PLC)-tracks and engaged in complementary convergence with other product markets or industries. We compare and contrast the theories that can explain, respectively, the PLC...
Privatization, convergence, and institutional autonomy
Rooijen, van M.
2011-01-01
Some of the trends incoming for 2011 – greater institutional autonomy, public/private convergence, entrepreneurial management, civic engagement – suggest innovation for hard times, with socio-economic and political rationales increasingly driving borderless developments. Others – open learning and
Converging Information and Communication Systems
DEFF Research Database (Denmark)
Øst, Alexander
2003-01-01
in the future to have - significant importance to the process and consequences of the convergence. The project focuses on the appliances, i.e. the TV sets, the computers and their peripheral equipment. It also takes into account the infrastructure and signals, which contain and deliver the information...
Evolution and convergence in telecommunications
Energy Technology Data Exchange (ETDEWEB)
Radicella, S; Grilli, D [Abdus Salam ICTP, Trieste (Italy)
2002-12-15
These lectures throw a spotlight on different aspects of the evolution of telecommunications networks, namely on the various facets of service and network convergence. The last years progress in data and telecommunications technologies, such as P-based networks, and the enormous potential of mobile communication systems and users' demands for comprehensive and network-independent have led to a convergence of data and telecommunications infrastructures in many aspects. In order to help the reader to an easier understanding of the phenomenon convergence, in the first two parts of this volume the evolution of the basic technologies is described one by one. This is done briefly and is focused on the principle topics, just to build a basis for the third part devoted to problems of convergence in telecommunications. These notes are addressed to those readers, who in a quick overview want to be informed on the future service and network landscape. The notes are equally suited for professionals with the desire to extend their horizon as well as for students looking for an introduction into telecommunications under more general aspects. The authors clearly understand the difficulties in writing a book devoted to the evolution in telecommunications. Today, telecom landscape varies at very high speed. Every few months new network technologies, new products and new services are developed. Attempts to present them in time can be accessible only for magazine publications or contributions to conferences. Therefore, in a number of areas, such as Voice over IP and new switching technologies not much more than the starting point of new paradigms is described. However, the content is up-to-date to a degree, that the phenomenon convergence can be fully understood. Partially, these notes are based on a number of lecture courses that were delivered during recent ICTP winter schools devoted to multimedia and digital communications.
Evolution and convergence in telecommunications
International Nuclear Information System (INIS)
Radicella, S.; Grilli, D.
2002-01-01
These lectures throw a spotlight on different aspects of the evolution of telecommunications networks, namely on the various facets of service and network convergence. The last years progress in data and telecommunications technologies, such as P-based networks, and the enormous potential of mobile communication systems and users' demands for comprehensive and network-independent have led to a convergence of data and telecommunications infrastructures in many aspects. In order to help the reader to an easier understanding of the phenomenon convergence, in the first two parts of this volume the evolution of the basic technologies is described one by one. This is done briefly and is focused on the principle topics, just to build a basis for the third part devoted to problems of convergence in telecommunications. These notes are addressed to those readers, who in a quick overview want to be informed on the future service and network landscape. The notes are equally suited for professionals with the desire to extend their horizon as well as for students looking for an introduction into telecommunications under more general aspects. The authors clearly understand the difficulties in writing a book devoted to the evolution in telecommunications. Today, telecom landscape varies at very high speed. Every few months new network technologies, new products and new services are developed. Attempts to present them in time can be accessible only for magazine publications or contributions to conferences. Therefore, in a number of areas, such as Voice over IP and new switching technologies not much more than the starting point of new paradigms is described. However, the content is up-to-date to a degree, that the phenomenon convergence can be fully understood. Partially, these notes are based on a number of lecture courses that were delivered during recent ICTP winter schools devoted to multimedia and digital communications
Did the Higgs boson drive the universe's expansion?
2008-01-01
The Higgs boson has been moonlighting. Not content with its day job of giving other particles their mass, it may also have driven the expansion of the early universe, given a little tinkering, according to two separate studies. Soon after the big bang the early universe is believed to have undergone a period of rapid expansion, known as inflation.
International Nuclear Information System (INIS)
Glashow, S.L.
1976-01-01
These are scattered remarks concerning what is happening to (not in) elementary particle physics. New developments are unfolding with unprecedented speed, so that one does not even attempt to give a comprehensive review at this time. Mostly charm is discussed, both its phenomenology and its impact on belief in quarks, chromodynamics, and unified theories. Beneath the newsworthy experimental discoveries of the last two years lies a quieter and more profound theoretical development: the emergence of a theory of particle physics
Quantifying convergence in the sciences
Directory of Open Access Journals (Sweden)
Sara Lumbreras
2016-02-01
Full Text Available Traditional epistemological models classify knowledge into separate disciplines with different objects of study and specific techniques, with some frameworks even proposing hierarchies (such as Comte’s. According to thinkers such as John Holland or Teilhard de Chardin, the advancement of science involves the convergence of disciplines. This proposed convergence can be studied in a number of ways, such as how works impact research outside a specific area (citation networks or how authors collaborate with other researchers in different fields (collaboration networks. While these studies are delivering significant new insights, they cannot easily show the convergence of different topics within a body of knowledge. This paper attempts to address this question in a quantitative manner, searching for evidence that supports the idea of convergence in the content of the sciences themselves (that is, whether the sciences are dealing with increasingly the same topics. We use Latent Dirichlet Analysis (LDA, a technique that is able to analyze texts and estimate the relative contributions of the topics that were used to generate them. We apply this tool to the corpus of the Santa Fe Institute (SFI working papers, which spans research on Complexity Science from 1989 to 2015. We then analyze the relatedness of the different research areas, the rise and demise of these sub-disciplines over time and, more broadly, the convergence of the research body as a whole. Combining the topic structure obtained from the collected publication history of the SFI community with techniques to infer hierarchy and clustering, we reconstruct a picture of a dynamic community which experiences trends, periodically recurring topics, and shifts in the closeness of scholarship over time. We find that there is support for convergence, and that the application of quantitative methods such as LDA to the study of knowledge can provide valuable insights that can help
Controlled Thermal Expansion Alloys
National Aeronautics and Space Administration — There has always been a need for controlled thermal expansion alloys suitable for mounting optics and detectors in spacecraft applications. These alloys help...
Convergence analysis in near-field imaging
International Nuclear Information System (INIS)
Bao, Gang; Li, Peijun
2014-01-01
This paper is devoted to the mathematical analysis of the direct and inverse modeling of the diffraction by a perfectly conducting grating surface in the near-field regime. It is motivated by our effort to analyze recent significant numerical results, in order to solve a class of inverse rough surface scattering problems in near-field imaging. In a model problem, the diffractive grating surface is assumed to be a small and smooth deformation of a plane surface. On the basis of the variational method, the direct problem is shown to have a unique weak solution. An analytical solution is introduced as a convergent power series in the deformation parameter by using the transformed field and Fourier series expansions. A local uniqueness result is proved for the inverse problem where only a single incident field is needed. On the basis of the analytic solution of the direct problem, an explicit reconstruction formula is presented for recovering the grating surface function with resolution beyond the Rayleigh criterion. Error estimates for the reconstructed grating surface are established with fully revealed dependence on such quantities as the surface deformation parameter, measurement distance, noise level of the scattering data, and regularity of the exact grating surface function. (paper)
Research on convergence of nuclear rotational spectra formula
International Nuclear Information System (INIS)
Chen Yongjing; Xu Fuxin
2001-01-01
The superdeformed bands in the A-190 region are systematically analyzed using four-parameter rotational spectra formula of Bohr-Mottelson's I(I + 1) expansion. The convergence of two-parameter ab formula is compared with that of three-parameter abc formula by four parameters A, B, C, D. The result shows that the four-parameter value relation does not support the theoretically expected values of ab and abc formulas, but comparatively the four-parameter value relation agrees with the theoretically expected value of ab formula better than that of abc formula
Convergent close-coupling calculations of low-energy positron-atomic-hydrogen scattering
International Nuclear Information System (INIS)
Bray, I.; Stelbovics, A.T.
1993-07-01
The convergent close coupling approach developed by the authors is applied to positron scattering from atomic hydrogen below the first excitation threshold. In this approach the multi-channel expansion one-electron states are obtained by diagonalizing the target Hamiltonian in a large Laguerre basis. It is demonstrated that this expansion of the scattering wave function is sufficient to reproduce the very accurate low-energy variational results, provided target states with l≤ 15 are included in the expansions. 10 refs., 1 tab
Cohen, J.S.; Suttorp, L.G.
1982-01-01
The generating functions for the collision brackets associated with two alternative convergent kinetic equations are derived for small values of the plasma parameter. It is shown that the first few terms in the asymptotic expansions of these generating functions are identical. Consequently, both
Fuel Thermal Expansion (FTHEXP)
International Nuclear Information System (INIS)
Reymann, G.A.
1978-07-01
A model is presented which deals with dimensional changes in LWR fuel pellets caused by changes in temperature. It is capable of dealing with any combination of UO 2 and PuO 2 in solid, liquid or mixed phase states, and includes expansion due to the solid-liquid phase change. The function FTHEXP models fuel thermal expansion as a function of temperature, fraction of PuO 2 , and the fraction of fuel which is molten
‘More Than a Television Channel’: Channel 4, FilmFour and a Failed Convergence Strategy
Directory of Open Access Journals (Sweden)
Hannah Andrews
2014-12-01
Full Text Available Obliged by act of Parliament to ‘innovate and experiment’, Channel 4 has, since its birth in 1982, been the UK’s most pioneering commercial television broadcaster. Its arrival broadened the meaning, function and operations of public service broadcasting in the UK, with a particular focus on minorities and pushing boundaries, political and creative. In the late 1990s, though, it was under increasing threat from specialist pay-TV services that could more accurately target its audiences. As a commercially funded channel with public service responsibilities, Channel 4 was under increasing pressure to be financially independent and fulfil a challenging remit. Its response to a threatened income and increasing competition was to diversify its portfolio into various media related businesses, particularly taking advantage of the arrival of digital television to expand its offer. The subtitle of the Corporation’s 2000 Annual report, ‘More than a Television Channel’ indicates the confidence, optimism and boldness with which this expansion was approached. The rapid expansion of the channel’s portfolio in a time of relative confidence in the commercial viability of the television industry was to be reversed only a few years later, when, after it failed to produce the returns it was designed for, 4Ventures was drastically scaled back, and Channel 4 refocused its efforts on the core broadcast channel. Channel 4 therefore offers a test case in the limits of convergence as a strategy for survival for British broadcasters at the arrival of digital television. This paper focuses specifically on the areas of Channel 4’s strategy that pertained to one of the broadcaster’s particular strengths: film culture. It explores one of the film offshoots of 4Ventures: FilmFour Ltd, the film finance, production, sales and distribution company and how its failure to find a commercial hit mirrors the general problems for a commercial public service broadcaster
Optimal separable bases and series expansions
International Nuclear Information System (INIS)
Poirier, B.
1997-01-01
A method is proposed for the efficient calculation of the Green close-quote s functions and eigenstates for quantum systems of two or more dimensions. For a given Hamiltonian, the best possible separable approximation is obtained from the set of all Hilbert-space operators. It is shown that this determination itself, as well as the solution of the resultant approximation, is a problem of reduced dimensionality. Moreover, the approximate eigenstates constitute the optimal separable basis, in the sense of self-consistent field theory. The full solution is obtained from the approximation via iterative expansion. In the time-independent perturbation expansion for instance, all of the first-order energy corrections are zero. In the Green close-quote s function case, we have a distorted-wave Born series with optimized convergence properties. This series may converge even when the usual Born series diverges. Analytical results are presented for an application of the method to the two-dimensional shifted harmonic-oscillator system, in the course of which the quantum tanh 2 potential problem is solved exactly. The universal presence of bound states in the latter is shown to imply long-lived resonances in the former. In a comparison with other theoretical methods, we find that the reaction path Hamiltonian fails to predict such resonances. copyright 1997 The American Physical Society
Economic convergence and climate policy
International Nuclear Information System (INIS)
Ciscar, J.C.; Soria, A.
2000-01-01
This paper addresses the relevance of the economic convergence hypotheses between the developing and the developed world in international greenhouse gas (GHG) emissions negotiations. The results are based on a two-region (the OECD and the rest of the world, ROW) neo-classical growth model with exogenous technical progress, different technological diffusion patterns, and a set of geophysical relationships that consider an environmental externality linked to GHG emissions. A game framework is taken into account in the model to capture the strategic interactions between agents. The outcome of the negotiations seems indeed to depend on the economic convergence hypotheses. Faster economic growth of the ROW countries would encourage them to further mitigate carbon emissions. (Author)
Global Monte Carlo Simulation with High Order Polynomial Expansions
International Nuclear Information System (INIS)
William R. Martin; James Paul Holloway; Kaushik Banerjee; Jesse Cheatham; Jeremy Conlin
2007-01-01
The functional expansion technique (FET) was recently developed for Monte Carlo simulation. The basic idea of the FET is to expand a Monte Carlo tally in terms of a high order expansion, the coefficients of which can be estimated via the usual random walk process in a conventional Monte Carlo code. If the expansion basis is chosen carefully, the lowest order coefficient is simply the conventional histogram tally, corresponding to a flat mode. This research project studied the applicability of using the FET to estimate the fission source, from which fission sites can be sampled for the next generation. The idea is that individual fission sites contribute to expansion modes that may span the geometry being considered, possibly increasing the communication across a loosely coupled system and thereby improving convergence over the conventional fission bank approach used in most production Monte Carlo codes. The project examined a number of basis functions, including global Legendre polynomials as well as 'local' piecewise polynomials such as finite element hat functions and higher order versions. The global FET showed an improvement in convergence over the conventional fission bank approach. The local FET methods showed some advantages versus global polynomials in handling geometries with discontinuous material properties. The conventional finite element hat functions had the disadvantage that the expansion coefficients could not be estimated directly but had to be obtained by solving a linear system whose matrix elements were estimated. An alternative fission matrix-based response matrix algorithm was formulated. Studies were made of two alternative applications of the FET, one based on the kernel density estimator and one based on Arnoldi's method of minimized iterations. Preliminary results for both methods indicate improvements in fission source convergence. These developments indicate that the FET has promise for speeding up Monte Carlo fission source convergence
Converging-barrel plasma accelerator
International Nuclear Information System (INIS)
Paine, T.O.
1971-01-01
The invention comprises a device for generating and accelerating plasma to extremely high velocity, while focusing the plasma to a decreasing cross section for attaining a very dense high-velocity plasma burst capable of causing nuclear fusion reactions. A converging coaxial accelerator-electrode configuration is employed with ''high-pressure'' gas injection in controlled amounts to achieve acceleration by deflagration and focusing by the shaped electromagnetic fields. (U.S.)
Surface meshing with curvature convergence
Li, Huibin; Zeng, Wei; Morvan, Jean-Marie; Chen, Liming; Gu, Xianfengdavid
2014-01-01
Surface meshing plays a fundamental role in graphics and visualization. Many geometric processing tasks involve solving geometric PDEs on meshes. The numerical stability, convergence rates and approximation errors are largely determined by the mesh qualities. In practice, Delaunay refinement algorithms offer satisfactory solutions to high quality mesh generations. The theoretical proofs for volume based and surface based Delaunay refinement algorithms have been established, but those for conformal parameterization based ones remain wide open. This work focuses on the curvature measure convergence for the conformal parameterization based Delaunay refinement algorithms. Given a metric surface, the proposed approach triangulates its conformal uniformization domain by the planar Delaunay refinement algorithms, and produces a high quality mesh. We give explicit estimates for the Hausdorff distance, the normal deviation, and the differences in curvature measures between the surface and the mesh. In contrast to the conventional results based on volumetric Delaunay refinement, our stronger estimates are independent of the mesh structure and directly guarantee the convergence of curvature measures. Meanwhile, our result on Gaussian curvature measure is intrinsic to the Riemannian metric and independent of the embedding. In practice, our meshing algorithm is much easier to implement and much more efficient. The experimental results verified our theoretical results and demonstrated the efficiency of the meshing algorithm. © 2014 IEEE.
Surface meshing with curvature convergence
Li, Huibin
2014-06-01
Surface meshing plays a fundamental role in graphics and visualization. Many geometric processing tasks involve solving geometric PDEs on meshes. The numerical stability, convergence rates and approximation errors are largely determined by the mesh qualities. In practice, Delaunay refinement algorithms offer satisfactory solutions to high quality mesh generations. The theoretical proofs for volume based and surface based Delaunay refinement algorithms have been established, but those for conformal parameterization based ones remain wide open. This work focuses on the curvature measure convergence for the conformal parameterization based Delaunay refinement algorithms. Given a metric surface, the proposed approach triangulates its conformal uniformization domain by the planar Delaunay refinement algorithms, and produces a high quality mesh. We give explicit estimates for the Hausdorff distance, the normal deviation, and the differences in curvature measures between the surface and the mesh. In contrast to the conventional results based on volumetric Delaunay refinement, our stronger estimates are independent of the mesh structure and directly guarantee the convergence of curvature measures. Meanwhile, our result on Gaussian curvature measure is intrinsic to the Riemannian metric and independent of the embedding. In practice, our meshing algorithm is much easier to implement and much more efficient. The experimental results verified our theoretical results and demonstrated the efficiency of the meshing algorithm. © 2014 IEEE.
Natural gas and electricity convergence
International Nuclear Information System (INIS)
Calger, C.
1998-01-01
Convergence between the gas and electricity industries was described as a means for creating an increasingly more efficient energy market where prices and fundamental relationships exist between gas and electricity. Convergence creates new opportunities for producers and consumers. Convergence will likely lead to the disaggregation of the electricity and gas industry into segments such as: (1) power generation and production, (2) transmission wires and pipelines, (3) wholesale merchants, (4) distribution wires and pipelines, and (5) retail marketing, services and administration. The de-integration of integrated utilities has already begun in the U.S. energy markets and retail open access is accelerating. This retail competition will create very demanding customers and the changing risk profile will create new issues for stakeholders. The pace of reform for the telecommunications, airlines, natural gas and electricity industries was graphically illustrated to serve as an example of what to expect. The different paths that the industry might take to deregulation (aggressively embrace reform, or defensively blocking it), and the likely consequences of each reaction were also described. A map indicating where U.S. electric and natural gas utility merger and acquisition activities have taken place between 1994-1997, was included. Another map showing the physical asset positions of the Enron grid, one of the largest independent oil and gas companies in the U.S., with increasing international operations, including an electric power transmission and distribution arm, was also provided as an illustration of a fully integrated energy market company of the future. 9 figs
Directory of Open Access Journals (Sweden)
Omar Gabriel da Silva Filho
2008-04-01
Full Text Available OBJETIVO: o presente trabalho tem como objetivo acompanhar radiograficamente a evolução da ossificação da sutura palatina mediana em pacientes submetidos à expansão rápida da maxila, bem como comprovar a validade de se avaliar a neoformação óssea através deste exame complementar de diagnóstico. METODOLOGIA: a amostra constou de 38 pacientes no estágio de dentadura mista que se submeteram ao protocolo de expansão rápida da maxila, sendo 2/4 de volta pela manhã e 2/4 de volta à noite, totalizando 1 volta completa por dia, compreendendo um período de 7 dias. RESULTADOS: radiografias oclusais de maxila tomadas no pós-tratamento evidenciaram uma variação individual quanto ao período necessário para a completa neoformação óssea da sutura palatina mediana. A imagem radiográfica apresentou-se como um método confiável para a determinação da época correta de remoção do aparelho expansor. Tendo em vista a estabilidade pós-tratamento a longo prazo, o aparelho expansor deve ser removido somente após a completa ossificação da sutura. CONCLUSÕES: os resultados revelaram que são necessários mais de três meses para que o processo de ossificação e reorganização sutural se processe após o procedimento de expansão rápida da maxila.OBJECTIVE: the current study aims at following up radiographically the evolution of the midpalatal suture during the expansion procedure since the opening of the suture until bone formation. METHODS: the sample comprised 38 patients in the mixed dentition stage submitted to the rapid palatal expansion protocol of the Hospital for Rehabilitation of Craniofacial Anomalies. RESULTS: it was observed an individual variation on the period of bone ossification of the midpalatal suture, which justifies the radiographic follow-up as determinant for the appliance removal. Due to long-term post-treatment stability, the expander should be removed after the new suture is completely formed. CONCLUSIONS
a globally convergent hyperpl onvergent hyperplane
African Journals Online (AJOL)
userpc
Bayero Journal of Pure and App. ISSN 2006 – 6996 ... Globally Convergent Hyper plane-BFGS method for solving nonline. The attractive ... Numerical performance on some b rates there liability ..... convergence of a class of quasi methods on ...
Density by Moduli and Lacunary Statistical Convergence
Directory of Open Access Journals (Sweden)
Vinod K. Bhardwaj
2016-01-01
Full Text Available We have introduced and studied a new concept of f-lacunary statistical convergence, where f is an unbounded modulus. It is shown that, under certain conditions on a modulus f, the concepts of lacunary strong convergence with respect to a modulus f and f-lacunary statistical convergence are equivalent on bounded sequences. We further characterize those θ for which Sθf=Sf, where Sθf and Sf denote the sets of all f-lacunary statistically convergent sequences and f-statistically convergent sequences, respectively. A general description of inclusion between two arbitrary lacunary methods of f-statistical convergence is given. Finally, we give an Sθf-analog of the Cauchy criterion for convergence and a Tauberian theorem for Sθf-convergence is also proved.
Stable convergence and stable limit theorems
Häusler, Erich
2015-01-01
The authors present a concise but complete exposition of the mathematical theory of stable convergence and give various applications in different areas of probability theory and mathematical statistics to illustrate the usefulness of this concept. Stable convergence holds in many limit theorems of probability theory and statistics – such as the classical central limit theorem – which are usually formulated in terms of convergence in distribution. Originated by Alfred Rényi, the notion of stable convergence is stronger than the classical weak convergence of probability measures. A variety of methods is described which can be used to establish this stronger stable convergence in many limit theorems which were originally formulated only in terms of weak convergence. Naturally, these stronger limit theorems have new and stronger consequences which should not be missed by neglecting the notion of stable convergence. The presentation will be accessible to researchers and advanced students at the master's level...
Spherical harmonic expansion of short-range screened Coulomb interactions
Energy Technology Data Exchange (ETDEWEB)
Angyan, Janos G [Laboratoire de Cristallographie et de Modelisation des Materiaux Mineraux et Biologiques, UMR 7036, CNRS-Universite Henri Poincare, BP 239, F-54506 Vandoeuvre-les-Nancy (France); Gerber, Iann [Laboratoire de Cristallographie et de Modelisation des Materiaux Mineraux et Biologiques, UMR 7036, CNRS-Universite Henri Poincare, BP 239, F-54506 Vandoeuvre-les-Nancy (France); Marsman, Martijn [Institut fuer Materialphysik and Center for Computational Materials Science, Universitaet Wien, Sensengasse 8, A-1090, Vienna (Austria)
2006-07-07
Spherical harmonic expansions of the screened Coulomb interaction kernel involving the complementary error function are required in various problems in atomic, molecular and solid state physics, like for the evaluation of Ewald-type lattice sums or for range-separated hybrid density functionals. A general analytical expression is derived for the kernel, which is non-separable in the radial variables. With the help of series expansions a separable approximate form is proposed, which is in close analogy with the conventional multipole expansion of the Coulomb kernel in spherical harmonics. The convergence behaviour of these expansions is studied and illustrated by the electrostatic potential of an elementary charge distribution formed by products of Slater-type atomic orbitals.
On the meaning of perturbation expansions in quantum field theory
International Nuclear Information System (INIS)
Burdik, C.; Chyla, J.
1987-01-01
We reformulate perturbation expansions in renormalized quantum field theories in a way that allows straightforward handling of situations when in the conventional approach (i.e. in fixed renormalization scheme) these expansions are divergent. In our approach the results of perturbation calculations of physical quantities appear in the form of (under certain circumstances) convergent expansions in powers of a free parameter χ, characterising the procedure involved. This inherent ambiguity of perturbative calculations is conjectures to be an expression of the underlaying ambiguity in the separation of the full theory into its perturbative and nonperturbative parts. The close connection of our results with the Borel summation technique is demonstrated and their relation to conventional perturbation expansions in fixed renormalization scheme is clarified
Technology assessment using NBIC convergence
International Nuclear Information System (INIS)
Vaseashta, Ashok
2009-01-01
Full text: Notwithstanding progress in the areas of nanotechnology/nanoscience, biotechnology, information technology, and cognitive sciences (NBIC), the synergy arising from convergence of these disciplines offers great potential for transformational, revolutionary, and embryonic opportunities with many technological applications. In addition, advances in synthesis and characterization methods have provided the means to study, understand, control, or even manipulate the transitional characteristics between isolated atoms and bulk material. In recent years, newly developed architectures in nanostructures and nanosystems with improved functionality, and ensuing unique characteristics have been developed with applications in chemical and biological sensors, nanobiotechnology, nanophotonics, and analysis of cellular processes. Novel convergence methodologies will integrate and advance next generation solutions to current and future technical challenges. Convergence in research methodologies transform the way research is conducted by overcoming specific barriers or filling existing knowledge gaps. NBIC Convergence and associated research methodologies has exceptionally high potential for transforming the manner in which state-of-the-art information is gathered, analyzed, and leveraged to enable future advances and applications. Examples of synergy of these disciplines include: label free, highly multiplexed over broad dynamic range, and decentralized nanotechnology based sensor platform for detection of biological and chemical agents; nucleic acid layers in conjunction with nanomaterials-based electrochemical or optical transducers as DNA Biosensor; potential targets for the next generation of vaccines, therapeutics and diagnostics to enhance human performance; basis for 'Gene Ontology' to provides an important link between gene function and systems biology to understand a global picture of host-microbe interactions - to name a few. Since the idea of 'Converging
Statistical convergence on intuitionistic fuzzy normed spaces
International Nuclear Information System (INIS)
Karakus, S.; Demirci, K.; Duman, O.
2008-01-01
Saadati and Park [Saadati R, Park JH, Chaos, Solitons and Fractals 2006;27:331-44] has recently introduced the notion of intuitionistic fuzzy normed space. In this paper, we study the concept of statistical convergence on intuitionistic fuzzy normed spaces. Then we give a useful characterization for statistically convergent sequences. Furthermore, we display an example such that our method of convergence is stronger than the usual convergence on intuitionistic fuzzy normed spaces
Convergence of barycentric coordinates to barycentric kernels
Kosinka, Jiří
2016-02-12
We investigate the close correspondence between barycentric coordinates and barycentric kernels from the point of view of the limit process when finer and finer polygons converge to a smooth convex domain. We show that any barycentric kernel is the limit of a set of barycentric coordinates and prove that the convergence rate is quadratic. Our convergence analysis extends naturally to barycentric interpolants and mappings induced by barycentric coordinates and kernels. We verify our theoretical convergence results numerically on several examples.
Convergence of barycentric coordinates to barycentric kernels
Kosinka, Jiří
2016-01-01
We investigate the close correspondence between barycentric coordinates and barycentric kernels from the point of view of the limit process when finer and finer polygons converge to a smooth convex domain. We show that any barycentric kernel is the limit of a set of barycentric coordinates and prove that the convergence rate is quadratic. Our convergence analysis extends naturally to barycentric interpolants and mappings induced by barycentric coordinates and kernels. We verify our theoretical convergence results numerically on several examples.
Expansion of protein domain repeats.
Directory of Open Access Journals (Sweden)
Asa K Björklund
2006-08-01
Full Text Available Many proteins, especially in eukaryotes, contain tandem repeats of several domains from the same family. These repeats have a variety of binding properties and are involved in protein-protein interactions as well as binding to other ligands such as DNA and RNA. The rapid expansion of protein domain repeats is assumed to have evolved through internal tandem duplications. However, the exact mechanisms behind these tandem duplications are not well-understood. Here, we have studied the evolution, function, protein structure, gene structure, and phylogenetic distribution of domain repeats. For this purpose we have assigned Pfam-A domain families to 24 proteomes with more sensitive domain assignments in the repeat regions. These assignments confirmed previous findings that eukaryotes, and in particular vertebrates, contain a much higher fraction of proteins with repeats compared with prokaryotes. The internal sequence similarity in each protein revealed that the domain repeats are often expanded through duplications of several domains at a time, while the duplication of one domain is less common. Many of the repeats appear to have been duplicated in the middle of the repeat region. This is in strong contrast to the evolution of other proteins that mainly works through additions of single domains at either terminus. Further, we found that some domain families show distinct duplication patterns, e.g., nebulin domains have mainly been expanded with a unit of seven domains at a time, while duplications of other domain families involve varying numbers of domains. Finally, no common mechanism for the expansion of all repeats could be detected. We found that the duplication patterns show no dependence on the size of the domains. Further, repeat expansion in some families can possibly be explained by shuffling of exons. However, exon shuffling could not have created all repeats.
International Nuclear Information System (INIS)
Dzenus, M.; Hundhausen, W.; Jansing, W.
1980-01-01
This discourse recounts efforts put into the SNR-2 project; specifically the development of compensation devices. The various prototypes of these compensation devices are described and the state of the development reviewed. Large Na (sodium)-heat transfer systems require a lot of valuable space if the component lay-out does not include compensation devices. So, in order to condense the spatial requirement as much as possible, expansion joints must be integrated into the pipe system. There are two basic types to suit the purpose: axial expansion joints and angular expansion joints. The expansion joints were developed on the basis of specific design criteria whereby differentiation is made between expansion joints of small and large nominal diameter. Expansion joints for installation in the sodium-filled primary piping are equipped with safety bellows in addition to the actual working bellows. Expansion joints must be designed and mounted in a manner to completely withstand seismic forces. The design must exclude any damage to the bellows during intermittent operations, that is, when sodium is drained the bellows' folds must be completely empty; otherwise residual solidified sodium could destroy the bellows when restarting. The expansion joints must be engineered on the basis of the following design data for the secondary system of the SNR project: working pressure: 16 bar; failure mode pressure: 5 events; failure mode: 5 sec., 28.5 bar, 520 deg. C; working temperature: 520 deg. C; temperature transients: 30 deg. C/sec.; service life: 200,000 h; number of load cycles: 10 4 ; material: 1.4948 or 1.4919; layer thickness of folds: 0.5 mm; angular deflection (DN 800): +3 deg. C or; axial expansion absorption (DN 600): ±80 mm; calculation: ASME class. The bellows' development work is not handled within this scope. The bellows are supplied by leading manufacturers, and warrant highest quality. Multiple bellows were selected on the basis of maximum elasticity - a property
Semantic Convergence in the Bilingual Lexicon
Ameel, Eef; Malt, Barbara C.; Storms, Gert; Van Assche, Fons
2009-01-01
Bilinguals' lexical mappings for their two languages have been found to converge toward a common naming pattern. The present paper investigates in more detail how semantic convergence is manifested in bilingual lexical knowledge. We examined how semantic convergence affects the centers and boundaries of lexical categories for common household…
"Nanoselves": NBIC and the Culture of Convergence
Venkatesan, Priya
2010-01-01
The subject of this essay is NBIC convergence (nanotechnology, biotechnology, information technology and cognitive science convergence). NBIC convergence is a recurring trope that is dominated by the paradigm of integration of the sciences. It is largely influenced by the considerations of social and economic impact, and it assumes positivism in…
Accelerating the loop expansion
International Nuclear Information System (INIS)
Ingermanson, R.
1986-01-01
This thesis introduces a new non-perturbative technique into quantum field theory. To illustrate the method, I analyze the much-studied phi 4 theory in two dimensions. As a prelude, I first show that the Hartree approximation is easy to obtain from the calculation of the one-loop effective potential by a simple modification of the propagator that does not affect the perturbative renormalization procedure. A further modification then susggests itself, which has the same nice property, and which automatically yields a convex effective potential. I then show that both of these modifications extend naturally to higher orders in the derivative expansion of the effective action and to higher orders in the loop-expansion. The net effect is to re-sum the perturbation series for the effective action as a systematic ''accelerated'' non-perturbative expansion. Each term in the accelerated expansion corresponds to an infinite number of terms in the original series. Each term can be computed explicitly, albeit numerically. Many numerical graphs of the various approximations to the first two terms in the derivative expansion are given. I discuss the reliability of the results and the problem of spontaneous symmetry-breaking, as well as some potential applications to more interesting field theories. 40 refs
Conformal expansions and renormalons
Energy Technology Data Exchange (ETDEWEB)
Rathsman, J.
2000-02-07
The coefficients in perturbative expansions in gauge theories are factorially increasing, predominantly due to renormalons. This type of factorial increase is not expected in conformal theories. In QCD conformal relations between observables can be defined in the presence of a perturbative infrared fixed-point. Using the Banks-Zaks expansion the authors study the effect of the large-order behavior of the perturbative series on the conformal coefficients. The authors find that in general these coefficients become factorially increasing. However, when the factorial behavior genuinely originates in a renormalon integral, as implied by a postulated skeleton expansion, it does not affect the conformal coefficients. As a consequence, the conformal coefficients will indeed be free of renormalon divergence, in accordance with previous observations concerning the smallness of these coefficients for specific observables. The authors further show that the correspondence of the BLM method with the skeleton expansion implies a unique scale-setting procedure. The BLM coefficients can be interpreted as the conformal coefficients in the series relating the fixed-point value of the observable with that of the skeleton effective charge. Through the skeleton expansion the relevance of renormalon-free conformal coefficients extends to real-world QCD.
Evidence for convergent evolution of SINE-directed Staufen-mediated mRNA decay.
Lucas, Bronwyn A; Lavi, Eitan; Shiue, Lily; Cho, Hana; Katzman, Sol; Miyoshi, Keita; Siomi, Mikiko C; Carmel, Liran; Ares, Manuel; Maquat, Lynne E
2018-01-30
Primate-specific Alu short interspersed elements (SINEs) as well as rodent-specific B and ID (B/ID) SINEs can promote Staufen-mediated decay (SMD) when present in mRNA 3'-untranslated regions (3'-UTRs). The transposable nature of SINEs, their presence in long noncoding RNAs, their interactions with Staufen, and their rapid divergence in different evolutionary lineages suggest they could have generated substantial modification of posttranscriptional gene-control networks during mammalian evolution. Some of the variation in SMD regulation produced by SINE insertion might have had a similar regulatory effect in separate mammalian lineages, leading to parallel evolution of the Staufen network by independent expansion of lineage-specific SINEs. To explore this possibility, we searched for orthologous gene pairs, each carrying a species-specific 3'-UTR SINE and each regulated by SMD, by measuring changes in mRNA abundance after individual depletion of two SMD factors, Staufen1 (STAU1) and UPF1, in both human and mouse myoblasts. We identified and confirmed orthologous gene pairs with 3'-UTR SINEs that independently function in SMD control of myoblast metabolism. Expanding to other species, we demonstrated that SINE-directed SMD likely emerged in both primate and rodent lineages >20-25 million years ago. Our work reveals a mechanism for the convergent evolution of posttranscriptional gene regulatory networks in mammals by species-specific SINE transposition and SMD.
International Nuclear Information System (INIS)
Taylor, D.
1984-01-01
This paper gives regression data for a modified second order polynomial fitted to the expansion data of, and percentage expansions for dioxides with (a) the fluorite and antifluorite structure: AmO 2 , BkO 2 , CeO 2 , CmO 2 , HfO 2 , Li 2 O, NpO 2 , PrO 2 , PuO 2 , ThO 2 , UO 2 , ZrO 2 , and (b) the rutile structure: CrO 2 , GeO 2 , IrO 2 , MnO 2 , NbO 2 , PbO 2 , SiO 2 , SnO 2 , TeO 2 , TiO 2 and VO 2 . Reduced expansion curves for the dioxides showed only partial grouping into iso-electronic series for the fluorite structures and showed that the 'law of corresponding states' did not apply to the rutile structures. (author)
A cluster expansion approach to exponential random graph models
International Nuclear Information System (INIS)
Yin, Mei
2012-01-01
The exponential family of random graphs are among the most widely studied network models. We show that any exponential random graph model may alternatively be viewed as a lattice gas model with a finite Banach space norm. The system may then be treated using cluster expansion methods from statistical mechanics. In particular, we derive a convergent power series expansion for the limiting free energy in the case of small parameters. Since the free energy is the generating function for the expectations of other random variables, this characterizes the structure and behavior of the limiting network in this parameter region
Improvement of the Convergence of the Invariant Imbedding T-Matrix Method
Zhai, S.; Panetta, R. L.; Yang, P.
2017-12-01
The invariant imbedding T-matrix method (IITM) is based on an electromagnetic volume integral equation to compute the T-matrix of an arbitrary scattering particle. A free-space Green's function is chosen as the integral kernel and thus each source point is placed in an imaginary vacuum spherical shell extending from the center to that source point. The final T-matrix (of the largest circumscribing sphere) is obtained through an iterative relation that, layer by layer, computes the T-matrix from the particle center to the outermost shell. On each spherical shell surface, an integration of the product of the refractive index 𝜀(𝜃, 𝜑) and vector spherical harmonics must be performed, resulting in the so-called U-matrix, which directly leads to the T-matrix on the spherical surface. Our observations indicate that the matrix size and sparseness are determined by the particular refractive index function 𝜀(𝜃, 𝜑). If 𝜀(𝜃, 𝜑) is an analytic function on the surface, then the matrix elements resulting from the integration decay rapidly, leading to sparse matrix; if 𝜀(𝜃, 𝜑) is not (for example, contains jump discontinuities), then the matrix elements decay slowly, leading to a large dense matrix. The intersection between an irregular scatterer and each spherical shell can leave jump discontinuities in 𝜀(𝜃, 𝜑) distributed over the shell surface. The aforementioned feature is analogous to the Gibbs phenomenon appearing in the orthogonal expansion of non-smooth functions with Hermitian eigenfunctions (complex exponential, Legendre, Bessel,...) where poor convergence speed is a direct consequence of the slow decay rate of the expansion coefficients. Various methods have been developed to deal with this slow convergence in the presence of discontinuities. Among the different approaches the most practical one may be a spectral filter: a filter is applied on the
Ecomorphological convergence in planktivorous surgeonfishes
Friedman, S. T.
2016-01-26
© 2016 European Society For Evolutionary Biology. Morphological convergence plays a central role in the study of evolution. Often induced by shared ecological specialization, homoplasy hints at underlying selective pressures and adaptive constraints that deterministically shape the diversification of life. Although midwater zooplanktivory has arisen in adult surgeonfishes (family Acanthuridae) at least four independent times, it represents a clearly specialized state, requiring the capacity to swiftly swim in midwater locating and sucking small prey items. Whereas this diet has commonly been associated with specific functional adaptations in fishes, acanthurids present an interesting case study as all nonplanktivorous species feed by grazing on benthic algae and detritus, requiring a vastly different functional morphology that emphasizes biting behaviours. We examined the feeding morphology in 30 acanthurid species and, combined with a pre-existing phylogenetic tree, compared the fit of evolutionary models across two diet regimes: zooplanktivores and nonzooplanktivorous grazers. Accounting for phylogenetic relationships, the best-fitting model indicates that zooplanktivorous species are converging on a separate adaptive peak from their grazing relatives. Driving this bimodal landscape, zooplanktivorous acanthurids tend to develop a slender body, reduced facial features, smaller teeth and weakened jaw adductor muscles. However, despite these phenotypic changes, model fitting suggests that lineages have not yet reached the adaptive peak associated with plankton feeding even though some transitions appear to be over 10 million years old. These findings demonstrate that the selective demands of pelagic feeding promote repeated - albeit very gradual - ecomorphological convergence within surgeonfishes, while allowing local divergences between closely related species, contributing to the overall diversity of the clade. Journal of Evolutionary Biology
Ecomorphological convergence in planktivorous surgeonfishes.
Friedman, S T; Price, S A; Hoey, A S; Wainwright, P C
2016-05-01
Morphological convergence plays a central role in the study of evolution. Often induced by shared ecological specialization, homoplasy hints at underlying selective pressures and adaptive constraints that deterministically shape the diversification of life. Although midwater zooplanktivory has arisen in adult surgeonfishes (family Acanthuridae) at least four independent times, it represents a clearly specialized state, requiring the capacity to swiftly swim in midwater locating and sucking small prey items. Whereas this diet has commonly been associated with specific functional adaptations in fishes, acanthurids present an interesting case study as all nonplanktivorous species feed by grazing on benthic algae and detritus, requiring a vastly different functional morphology that emphasizes biting behaviours. We examined the feeding morphology in 30 acanthurid species and, combined with a pre-existing phylogenetic tree, compared the fit of evolutionary models across two diet regimes: zooplanktivores and nonzooplanktivorous grazers. Accounting for phylogenetic relationships, the best-fitting model indicates that zooplanktivorous species are converging on a separate adaptive peak from their grazing relatives. Driving this bimodal landscape, zooplanktivorous acanthurids tend to develop a slender body, reduced facial features, smaller teeth and weakened jaw adductor muscles. However, despite these phenotypic changes, model fitting suggests that lineages have not yet reached the adaptive peak associated with plankton feeding even though some transitions appear to be over 10 million years old. These findings demonstrate that the selective demands of pelagic feeding promote repeated - albeit very gradual - ecomorphological convergence within surgeonfishes, while allowing local divergences between closely related species, contributing to the overall diversity of the clade. © 2016 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2016 European
Giovannini, Massimo
2015-01-01
Cosmological singularities are often discussed by means of a gradient expansion that can also describe, during a quasi-de Sitter phase, the progressive suppression of curvature inhomogeneities. While the inflationary event horizon is being formed the two mentioned regimes coexist and a uniform expansion can be conceived and applied to the evolution of spatial gradients across the protoinflationary boundary. It is argued that conventional arguments addressing the preinflationary initial conditions are necessary but generally not sufficient to guarantee a homogeneous onset of the conventional inflationary stage.
Convergence estimates in approximation theory
Gupta, Vijay
2014-01-01
The study of linear positive operators is an area of mathematical studies with significant relevance to studies of computer-aided geometric design, numerical analysis, and differential equations. This book focuses on the convergence of linear positive operators in real and complex domains. The theoretical aspects of these operators have been an active area of research over the past few decades. In this volume, authors Gupta and Agarwal explore new and more efficient methods of applying this research to studies in Optimization and Analysis. The text will be of interest to upper-level students seeking an introduction to the field and to researchers developing innovative approaches.
SCORE DIGITAL TECHNOLOGY: THE CONVERGENCE
Directory of Open Access Journals (Sweden)
Chernyshov Alexander V.
2013-12-01
Full Text Available Explores the role of digital scorewriters in today's culture, education, and music industry and media environment. The main principle of the development of software is not only publishing innovation (relating to the sheet music, and integration into the area of composition, arrangement, education, creative process for works based on digital technology (films, television and radio broadcasting, Internet, audio and video art. Therefore the own convergence of musically-computer technology is a total phenomenon: notation program combined with means MIDI-sequencer, audio and video editor. The article contains the unique interview with the creator of music notation processors.
DEFF Research Database (Denmark)
Henriksen, Lars Skov; Zimmer, Annette; Smith, Steven Rathgeb
. Specifically, we will investigate whether and to what extent social services and health care in these three countries are affected by current changes. With a special focus on nonprofit organizations, we will particularly address the question whether a trend towards convergence of the very different welfare......Due to severe societal, economic and political changes, of which the financial crisis counts prominently, welfare states all over the world are under stress. In our comparative analysis, we will concentrate on specific segments of welfare state activity in Denmark, Germany, and the United States...
Low-temperature thermal expansion
International Nuclear Information System (INIS)
Collings, E.W.
1986-01-01
This chapter discusses the thermal expansion of insulators and metals. Harmonicity and anharmonicity in thermal expansion are examined. The electronic, magnetic, an other contributions to low temperature thermal expansion are analyzed. The thermodynamics of the Debye isotropic continuum, the lattice-dynamical approach, and the thermal expansion of metals are discussed. Relative linear expansion at low temperatures is reviewed and further calculations of the electronic thermal expansion coefficient are given. Thermal expansions are given for Cu, Al and Ti. Phenomenologic thermodynamic relationships are also discussed
Directory of Open Access Journals (Sweden)
Gustavo Mattos Barreto
2005-12-01
Full Text Available OBJETIVO: na presente pesquisa utilizou-se o aparelho Hyrax tendo como objetivo avaliar as alterações transversais e verticais da maxila. Foram selecionados 20 pacientes de ambos os gêneros, entre 7 e 11 anos de idade, que apresentavam mordida cruzada posterior uni ou bilateral. METODOLOGIA: foram realizadas telerradiografias em norma frontal (PA antes e após a expansão. A fim de evitar que a falta de padronização dessas radiografias pudesse influenciar nos resultados, idealizou-se um método de padronização para tais radiografias. RESULTADOS E CONCLUSÕES: os resultados mostraram que a correção da mordida cruzada posterior com o aparelho Hyrax, que ocorreu em todos os casos, foi em função tanto da abertura da sutura palatina mediana como também da inclinação dos molares. A medida JgE-JgD relacionada com a expansão maxilar aumentou significantemente em todos os casos tratados. Nas avaliações dentárias, as medidas verticais não apresentaram diferenças significantes, ao contrário das medidas transversais (FTE-FTD; FBE-FBD; LO.BTE; LO.BTD; BTE.BTD. A largura da cavidade nasal também aumentou significantemente (CNE-CND. O método de padronização proposto permite, portanto, utilizar as medidas que avaliam a expansão rápida da maxila, através das radiografias póstero-anteriores, com segurança, também no sentido vertical.AIM: in the atresia maxillary cases, the most indicated treatment is rapid maxillary expansion that can be achieved by different therapies. In the present research the Hyrax appliance was used in order to evaluate the transverse and vertical outcomes in maxillary base. METHODS: twenty patients of both gender, from 7 to 11 years old, presenting uni or bilateral posterior crossbite were selected. Posteroanterior radiographs were performed before and after expansion. These radiographs were standardized in order to avoid that problems with lack of standardization influence the results. RESULTS AND CONCLUSION
A staggered conservative scheme for every Froude number in rapidly varied shallow water flows
Stelling, G. S.; Duinmeijer, S. P. A.
2003-12-01
This paper proposes a numerical technique that in essence is based upon the classical staggered grids and implicit numerical integration schemes, but that can be applied to problems that include rapidly varied flows as well. Rapidly varied flows occur, for instance, in hydraulic jumps and bores. Inundation of dry land implies sudden flow transitions due to obstacles such as road banks. Near such transitions the grid resolution is often low compared to the gradients of the bathymetry. In combination with the local invalidity of the hydrostatic pressure assumption, conservation properties become crucial. The scheme described here, combines the efficiency of staggered grids with conservation properties so as to ensure accurate results for rapidly varied flows, as well as in expansions as in contractions. In flow expansions, a numerical approximation is applied that is consistent with the momentum principle. In flow contractions, a numerical approximation is applied that is consistent with the Bernoulli equation. Both approximations are consistent with the shallow water equations, so under sufficiently smooth conditions they converge to the same solution. The resulting method is very efficient for the simulation of large-scale inundations.
Comparison of the unitary pole and Adhikari-Sloan expansions in the three nucleon system
International Nuclear Information System (INIS)
Afnan, I.R.; Birrell, N.D.
1977-01-01
The binding energy of 3 H, percentage S-, S'- and D-state probability, and charge form factor of 3 He are calculated using the unitary pole and Adhikari-Sloan separable expansions to the Reid soft core potential. Comparison of the results for the two separable expansions show that the expansion of Adhikari and Sloan has the better convergence property, and the lowest rank expansion considered (equivalent to the unitary pole approximation) gives a good approximation to the binding energy of 3 H and the charge form factor of 3 He, even at large momentum transfer (K 2 -2 ). (Author)
International Nuclear Information System (INIS)
Altac, Zekeriya
2007-01-01
Generalized exponential integral functions (GEIF) are encountered in multi-dimensional thermal radiative transfer problems in the integral equation kernels. Several series expansions for the first-order generalized exponential integral function, along with a series expansion for the general nth order GEIF, are derived. The convergence issues of these series expansions are investigated numerically as well as theoretically, and a recurrence relation which does not require derivatives of the GEIF is developed. The exact series expansions of the two dimensional cylindrical and/or two-dimensional planar integral kernels as well as their spatial moments have been explicitly derived and compared with numerical values
Pointwise convergence of Fourier series
Arias de Reyna, Juan
2002-01-01
This book contains a detailed exposition of Carleson-Hunt theorem following the proof of Carleson: to this day this is the only one giving better bounds. It points out the motivation of every step in the proof. Thus the Carleson-Hunt theorem becomes accessible to any analyst.The book also contains the first detailed exposition of the fine results of Hunt, Sjölin, Soria, etc on the convergence of Fourier Series. Its final chapters present original material. With both Fefferman's proof and the recent one of Lacey and Thiele in print, it becomes more important than ever to understand and compare these two related proofs with that of Carleson and Hunt. These alternative proofs do not yield all the results of the Carleson-Hunt proof. The intention of this monograph is to make Carleson's proof accessible to a wider audience, and to explain its consequences for the pointwise convergence of Fourier series for functions in spaces near $äcal Lü^1$, filling a well-known gap in the literature.
Bolthausen, Erwin; Van Der Hofstad, Remco; Kozma, Gady
2018-01-01
We show Green's function asymptotic upper bound for the two-point function of weakly self-Avoiding walk in d >4, revisiting a classic problem. Our proof relies on Banach algebras to analyse the lace-expansion fixed point equation and is simpler than previous approaches in that it avoids Fourier
OPEC future capacity expansions
International Nuclear Information System (INIS)
Sandrea, I.
2005-01-01
This conference presentation examined OPEC future capacity expansions including highlights from 2000-2004 from the supply perspective and actions by OPEC; OPEC spare capacity in 2005/2006; medium-term capacity expansion and investments; long-term scenarios, challenges and opportunities; and upstream policies in member countries. Highlights from the supply perspective included worst than expected non-OPEC supply response; non-OPEC supply affected by a number of accidents and strikes; geopolitical tensions; and higher than expected demand for OPEC crude. OPEC's actions included closer relationship with other producers and consumers; capacity expansions in 2004 and 2005/2006; and OPEC kept the market well supplied with crude in 2004. The presentation also provided data using graphical charts on OPEC net capacity additions until 2005/2006; OPEC production versus spare capacity from 2003 to 2005; OPEC production and capacity to 2010; and change in required OPEC production from 2005-2020. Medium term expansion to 2010 includes over 60 projects. Medium-term risks such as project execution, financing, costs, demand, reserves, depletion, integration of Iraq, and geopolitical tensions were also discussed. The presentation concluded that in the long term, large uncertainties remain; the peak of world supply is not imminent; and continued and enhanced cooperation is essential to market stability. tabs., figs
Physics suggests that the interplay of momentum, continuity, and geometry in outward radial flow must produce density and concomitant pressure reductions. In other words, this flow is intrinsically auto-expansive. It has been proposed that this process is the key to understanding...
Emerging interdisciplinary fields in the coming intelligence/convergence era
Noor, Ahmed K.
2012-09-01
Dramatic advances are in the horizon resulting from rapid pace of development of several technologies, including, computing, communication, mobile, robotic, and interactive technologies. These advances, along with the trend towards convergence of traditional engineering disciplines with physical, life and other science disciplines will result in the development of new interdisciplinary fields, as well as in new paradigms for engineering practice in the coming intelligence/convergence era (post-information age). The interdisciplinary fields include Cyber Engineering, Living Systems Engineering, Biomechatronics/Robotics Engineering, Knowledge Engineering, Emergent/Complexity Engineering, and Multiscale Systems engineering. The paper identifies some of the characteristics of the intelligence/convergence era, gives broad definition of convergence, describes some of the emerging interdisciplinary fields, and lists some of the academic and other organizations working in these disciplines. The need is described for establishing a Hierarchical Cyber-Physical Ecosystem for facilitating interdisciplinary collaborations, and accelerating development of skilled workforce in the new fields. The major components of the ecosystem are listed. The new interdisciplinary fields will yield critical advances in engineering practice, and help in addressing future challenges in broad array of sectors, from manufacturing to energy, transportation, climate, and healthcare. They will also enable building large future complex adaptive systems-of-systems, such as intelligent multimodal transportation systems, optimized multi-energy systems, intelligent disaster prevention systems, and smart cities.
Convergent Validity of the PUTS
Directory of Open Access Journals (Sweden)
Valerie Cathérine Brandt
2016-04-01
Full Text Available Premonitory urges are a cardinal feature in Gilles de la Tourette syndrome. Severity of premonitory urges can be assessed with the Premonitory Urge for Tic Disorders Scale (PUTS. However, convergent validity of the measure has been difficult to assess due to the lack of other urge measures.We investigated the relationship between average real-time urge intensity assessed by an in-house developed real-time urge monitor, measuring urge intensity continuously for 5mins on a visual analogue scale, and general urge intensity assessed by the PUTS in 22 adult Tourette patients (mean age 29.8+/- 10.3; 19 male. Additionally, underlying factors of premonitory urges assessed by the PUTS were investigated in the adult sample using factor analysis and were replicated in 40 children and adolescents diagnosed with Tourette syndrome (mean age 12.05 +/- 2.83 SD, 31 male.Cronbach’s alpha for the PUTS10 was acceptable (α = .79 in the adult sample. Convergent validity between average real-time urge intensity scores (as assessed with the real-time urge monitor and the 10-item version of the PUTS (r = .64 and the 9-item version of the PUTS (r = .66 was good. A factor analysis including the 10 items of the PUTS and average real-time urge intensity scores revealed three factors. One factor included the average real-time urge intensity score and appeared to measure urge intensity, while the other two factors can be assumed to reflect the (sensory quality of urges and subjective control, respectively. The factor structure of the 10 PUTS items alone was replicated in a sample of children and adolescents.The results indicate that convergent validity between the PUTS and the real-time urge assessment monitor is good. Furthermore, the results suggest that the PUTS might assess more than one dimension of urges and it may be worthwhile developing different sub-scales of the PUTS assessing premonitory urges in terms of intensity and quality, as well as subjectively
Professional convergence in forensic practice.
Mercer, D; Mason, T; Richman, J
2001-06-01
This paper outlines the development and convergence of forensic science and secure psychiatric services in the UK, locating the professionalization of forensic nursing within a complex web of political, economic, and ideological structures. It is suggested that a stagnation of the therapeutic enterprise in high and medium security provision has witnessed an intrusion of medical power into the societal body. Expanding technologies of control and surveillance are discussed in relation to the move from modernity to postmodernity and the ongoing dynamic of medicalized offending. Four aspects of globalization are identified as impacting upon the organization and application of forensic practice: (i) organized capitalism and the exhaustion of the welfare state; (ii) security versus danger and trust versus risk; (iii) science as a meta-language; and (iv) foreclosure as a mechanism of censorship. Finally, as a challenge for the profession, some predictions are offered about the future directions or demise of forensic nursing.
Mosaic convergence of rodent dentitions.
Directory of Open Access Journals (Sweden)
Vincent Lazzari
Full Text Available BACKGROUND: Understanding mechanisms responsible for changes in tooth morphology in the course of evolution is an area of investigation common to both paleontology and developmental biology. Detailed analyses of molar tooth crown shape have shown frequent homoplasia in mammalian evolution, which requires accurate investigation of the evolutionary pathways provided by the fossil record. The necessity of preservation of an effective occlusion has been hypothesized to functionally constrain crown morphological changes and to also facilitate convergent evolution. The Muroidea superfamily constitutes a relevant model for the study of molar crown diversification because it encompasses one third of the extant mammalian biodiversity. METHODOLOGY/PRINCIPAL FINDINGS: Combined microwear and 3D-topographic analyses performed on fossil and extant muroid molars allow for a first quantification of the relationships between changes in crown morphology and functionality of occlusion. Based on an abundant fossil record and on a well resolved phylogeny, our results show that the most derived functional condition associates longitudinal chewing and non interlocking of cusps. This condition has been reached at least 7 times within muroids via two main types of evolutionary pathways each respecting functional continuity. In the first type, the flattening of tooth crown which induces the removal of cusp interlocking occurs before the rotation of the chewing movement. In the second type however, flattening is subsequent to rotation of the chewing movement which can be associated with certain changes in cusp morphology. CONCLUSION/SIGNIFICANCE: The reverse orders of the changes involved in these different pathways reveal a mosaic evolution of mammalian dentition in which direction of chewing and crown shape seem to be partly decoupled. Either can change in respect to strong functional constraints affecting occlusion which thereby limit the number of the possible
Time evolution of the wave equation using rapid expansion method
Pestana, Reynam C.; Stoffa, Paul L.
2010-01-01
Forward modeling of seismic data and reverse time migration are based on the time evolution of wavefields. For the case of spatially varying velocity, we have worked on two approaches to evaluate the time evolution of seismic wavefields. An exact solution for the constant-velocity acoustic wave equation can be used to simulate the pressure response at any time. For a spatially varying velocity, a one-step method can be developed where no intermediate time responses are required. Using this approach, we have solved for the pressure response at intermediate times and have developed a recursive solution. The solution has a very high degree of accuracy and can be reduced to various finite-difference time-derivative methods, depending on the approximations used. Although the two approaches are closely related, each has advantages, depending on the problem being solved. © 2010 Society of Exploration Geophysicists.
Reducing the global environmental impacts of rapid infrastructure expansion
Laurance, William F.; Peletier-Jellema, Anna; Geenen, Bart; Koster, Harko; Verweij, Pita|info:eu-repo/dai/nl/145431843; Van Dijck, Pitou; Lovejoy, Thomas E.; Schleicher, Judith; Van Kuijk, Marijke|info:eu-repo/dai/nl/304834319
2015-01-01
Infrastructures, such as roads, mines, and hydroelectric dams, are proliferating explosively. Often, this has serious direct and indirect environmental impacts. We highlight nine issues that should be considered by project proponents to better evaluate and limit the environmental risks of such
Evaluation of Two Different Rapid Maxillary Expansion Surgical ...
African Journals Online (AJOL)
2018-02-07
Feb 7, 2018 ... 2018 Nigerian Journal of Clinical Practice | Published by Wolters Kluwer ‑ Medknow ..... incisors were covered with acrylic resin [Figure 1]. The occlusal surfaces ... Multi-Cure Glass Ionomer Orthodontic Band Cement; 3M.
Time evolution of the wave equation using rapid expansion method
Pestana, Reynam C.
2010-07-01
Forward modeling of seismic data and reverse time migration are based on the time evolution of wavefields. For the case of spatially varying velocity, we have worked on two approaches to evaluate the time evolution of seismic wavefields. An exact solution for the constant-velocity acoustic wave equation can be used to simulate the pressure response at any time. For a spatially varying velocity, a one-step method can be developed where no intermediate time responses are required. Using this approach, we have solved for the pressure response at intermediate times and have developed a recursive solution. The solution has a very high degree of accuracy and can be reduced to various finite-difference time-derivative methods, depending on the approximations used. Although the two approaches are closely related, each has advantages, depending on the problem being solved. © 2010 Society of Exploration Geophysicists.
Expansion of the uranium mines in the Elliot Lake area
International Nuclear Information System (INIS)
1979-11-01
This report forms the response of the government of Ontario to an earlier report issued by an Envrionmental Assessment Board. Specifically, the report deals with the rapid growth of the town of Elliot Lake due to expansion of several uranium mine-mill operations. Rapid growth of small communities presents considerable problems in providing housing, essential services, and educational facilities. Several specific actions taken by the government to help the town cope with rapid growth are presented. (O.T.)
International Nuclear Information System (INIS)
Lewis, C.
1997-01-01
The Olympic Dam orebody is the 6th largest copper and the single largest uranium orebody in the world. Mine production commenced in June 1988, at an annual production rate of around 45,000 tonnes of copper and 1,000 tonnes of uranium. Western Mining Corporation announced in 1996 a proposed $1.25 billion expansion of the Olympic Dam operation to raise the annual production capacity of the mine to 200,000 tonnes of copper, approximately 3,700 tonnes of uranium, 75,000 ounces of gold and 950,000 ounces of silver by 2001. Further optimisation work has identified a faster track expansion route, with an increase in the capital cost to $1.487 billion but improved investment outcome, a new target completion date of end 1999, and a new uranium output of 4,600 tonnes per annum from that date
Financing electricity expansion
International Nuclear Information System (INIS)
Hyman, L.S.
1994-01-01
Expansion of electricity supply is associated with economic development. The installation and enlargement of power systems in developing countries entails a huge financial burden, however. Energy consumers in such countries must pay not only for supplies but for the cost of raising the capital for expansion on the international markets. Estimates are presented for the capital expenditure for electricity supply over the period 1990 to 2020 for the major world regions, using approximations for the cost of plant and capital and for the returns earned. These data lead to the conclusion that the five regions with the lowest per capita incomes are those which will need the major part of the capital expenditure and the highest percentage of external finance. (6 tables) (UK)
Bigravity from gradient expansion
International Nuclear Information System (INIS)
Yamashita, Yasuho; Tanaka, Takahiro
2016-01-01
We discuss how the ghost-free bigravity coupled with a single scalar field can be derived from a braneworld setup. We consider DGP two-brane model without radion stabilization. The bulk configuration is solved for given boundary metrics, and it is substituted back into the action to obtain the effective four-dimensional action. In order to obtain the ghost-free bigravity, we consider the gradient expansion in which the brane separation is supposed to be sufficiently small so that two boundary metrics are almost identical. The obtained effective theory is shown to be ghost free as expected, however, the interaction between two gravitons takes the Fierz-Pauli form at the leading order of the gradient expansion, even though we do not use the approximation of linear perturbation. We also find that the radion remains as a scalar field in the four-dimensional effective theory, but its coupling to the metrics is non-trivial.
International Nuclear Information System (INIS)
Suess, S.T.
1987-01-01
Magnetic clouds are a carefully defined subclass of all interplanetary signatures of coronal mass ejections whose geometry is thought to be that of a cylinder embedded in a plane. It has been found that the total magnetic pressure inside the clouds is higher than the ion pressure outside, and that the clouds are expanding at 1 AU at about half the local Alfven speed. The geometry of the clouds is such that even though the magnetic pressure inside is larger than the total pressure outside, expansion will not occur because the pressure is balanced by magnetic tension - the pinch effect. The evidence for expansion of clouds at 1 AU is nevertheless quite strong so another reason for its existence must be found. It is demonstrated that the observations can be reproduced by taking into account the effects of geometrical distortion of the low plasma beta clouds as they move away from the Sun
Beyond Brainstorming: Exploring Convergence in Teams
Seeber, Isabella; de Vreede, Gert-Jan; Maier, Ronald; Weber, Barbara
2017-01-01
Abstract Collaborative brainstorming is often followed by a convergence activity where teams extract the most promising ideas on a useful level of detail from the brainstorming results. Contrary to the wealth of research on electronic brainstorming, there is a dearth of research on convergence. We used experimental methods for an in-depth exploration of two facilitation-based interventions in a convergence activity: attention guidance (focusing participants on procedures to execute a convergence task) and discussion encouragement (engaging participants in conversations to combine knowledge on ideas). Our findings show that both attention guidance and discussion encouragement are correlated with higher convergence quality. We argue that attention guidance’s contribution is in its support of coordination, information processing, and goal specification. Similar, we argue that discussion encouragement’s contribution is in its stimulation of idea clarification and idea combination. Contrary to past research, our findings further show that satisfaction was higher after convergence than after brainstorming. PMID:29399005
Vadose zone flow convergence test suite
Energy Technology Data Exchange (ETDEWEB)
Butcher, B. T. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)
2017-06-05
Performance Assessment (PA) simulations for engineered disposal systems at the Savannah River Site involve highly contrasting materials and moisture conditions at and near saturation. These conditions cause severe convergence difficulties that typically result in unacceptable convergence or long simulation times or excessive analyst effort. Adequate convergence is usually achieved in a trial-anderror manner by applying under-relaxation to the Saturation or Pressure variable, in a series of everdecreasing RELAxation values. SRNL would like a more efficient scheme implemented inside PORFLOW to achieve flow convergence in a more reliable and efficient manner. To this end, a suite of test problems that illustrate these convergence problems is provided to facilitate diagnosis and development of an improved convergence strategy. The attached files are being transmitted to you describing the test problem and proposed resolution.
Regional Convergence and Sustainable Development in China
Directory of Open Access Journals (Sweden)
Fang Yang
2016-01-01
Full Text Available Based on the convergence theory of economic growth, this paper extends this concept to the human development index and carries out an empirical analysis of regional development in China between 1997 and 2006. Our research shows that the conditional convergence has been identified. Investment in fixed assets, government expenditure on education, health and infrastructure construction have positive effects on regional convergence of social development. Population weighted analysis of human development index provides support for weak convergence amongst provinces. Analysis of dynamics of regional distribution reveals the club convergence, which indicate two different convergence states. Central China is in the shade and lags behind, giving rise to the so-called “central downfall”. To solve this problem, the “Rise of Central China” Plan is necessary to promote the connection between coastal and inland regions of China and reduce the regional development gap.
IKEA's International Expansion
Harapiak, Clayton
2013-01-01
This case concerns a global retailing firm that is dealing with strategic management and marketing issues. Applying a scenario of international expansion, this case provides a thorough analysis of the current business environment for IKEA. Utilizing a variety of methods (e.g. SWOT, PESTLE, McKinsey Matrix) the overall objective is to provide students with the opportunity to apply their research skills and knowledge regarding a highly competitive industry to develop strategic marketing strateg...
International Nuclear Information System (INIS)
Matsuki, Takayuki
1976-01-01
Symmetric eikonal expansion for the scattering amplitude is formulated for nonrelativistic and relativistic potential scatterings and also for the quantum field theory. The first approximations coincide with those of Levy and Sucher. The obtained scattering amplitudes are time reversal invariant for all cases and are crossing symmetric for the quantum field theory in each order of approximation. The improved eikonal phase introduced by Levy and Sucher is also derived from the different approximation scheme from the above. (auth.)
Series expansions without diagrams
International Nuclear Information System (INIS)
Bhanot, G.; Creutz, M.; Horvath, I.; Lacki, J.; Weckel, J.
1994-01-01
We discuss the use of recursive enumeration schemes to obtain low- and high-temperature series expansions for discrete statistical systems. Using linear combinations of generalized helical lattices, the method is competitive with diagrammatic approaches and is easily generalizable. We illustrate the approach using Ising and Potts models. We present low-temperature series results in up to five dimensions and high-temperature series in three dimensions. The method is general and can be applied to any discrete model
convergent methods for calculating thermodynamic Green functions
Bowen, S. P.; Williams, C. D.; Mancini, J. D.
1984-01-01
A convergent method of approximating thermodynamic Green functions is outlined briefly. The method constructs a sequence of approximants which converges independently of the strength of the Hamiltonian's coupling constants. Two new concepts associated with the approximants are introduced: the resolving power of the approximation, and conditional creation (annihilation) operators. These ideas are illustrated on an exactly soluble model and a numerical example. A convergent expression for the s...
On statistical acceleration convergence of double sequences
Directory of Open Access Journals (Sweden)
Bipan Hazarika
2017-04-01
Full Text Available In this article the notion of statistical acceleration convergence of double sequences in Pringsheim's sense has been introduced. We prove the decompostion theorems for statistical acceleration convergence of double sequences and some theorems related to that concept have been established using the four dimensional matrix transformations. We provided some examples, where the results of acceleration convergence fails to hold for the statistical cases.
International Nuclear Information System (INIS)
Pathak, R.K.; Chandra, A.K.; Bhattacharyya, K.
1994-01-01
Eigenfunctions of the quantum mechanical particle-in-a-box problem are shown to lead to a new trigonometric expansion scheme with good convergence properties. This hitherto unexplored expansion strategy is found to be quite efficient in variational calculations and as an alternative to the Fourier series. Demonstrative computations involve a few one-dimensional models of confining potentials for bound states and pulses of various shapes in signal analysis. ((orig.))
Separable expansion for realistic multichannel scattering problems
International Nuclear Information System (INIS)
Canton, L.; Cattapan, G.; Pisent, G.
1987-01-01
A new approach to the multichannel scattering problem with realistic local or nonlocal interactions is developed. By employing the negative-energy solutions of uncoupled Sturmian eigenvalue problems referring to simple auxiliary potentials, the coupling interactions appearing to the original multichannel problem are approximated by finite-rank potentials. By resorting to integral-equation tecniques the coupled-channel equations are then reduced to linear algebraic equations which can be straightforwardly solved. Compact algebraic expressions for the relevant scattering matrix elements are thus obtained. The convergence of the method is tasted in the single-channel case with realistic optical potentials. Excellent agreement is obtained with a few terms in the separable expansion for both real and absorptive interactions
Increasing dominance of IT in ICT convergence
DEFF Research Database (Denmark)
Henten, Anders; Tadayoni, Reza
The aim of the paper is to examine the increasing dominance of IT companies in the converging ICT industry and, on the basis of this development, to contribute to extending the theoretical understanding of market and industry convergence in the ICT area.......The aim of the paper is to examine the increasing dominance of IT companies in the converging ICT industry and, on the basis of this development, to contribute to extending the theoretical understanding of market and industry convergence in the ICT area....
Convergence as conditionant for Media Regulation
Directory of Open Access Journals (Sweden)
Othon Jambeiro
2011-01-01
Full Text Available Convergence comprises a combination of interlinked and interdependent transformations, of technological, industrial, commercial, cultural and social nature, which affect communication regulation. Customers, at their time, turned also convergent, involved in an intense participative culture, which is too, from the point of view of its social and geographical range, thanks to convergence, more and more extense. Instead of passive consumers of media and information and communication services, we have now active and socially connected consumers, no more readers/spectators/listeners, but noisy activists and publishers. To understand this phenomenon is essential to discern a regulatory frame suitable for it. This paper tries to define convergence and to discuss its consequences.
Quadratically convergent MCSCF scheme using Fock operators
International Nuclear Information System (INIS)
Das, G.
1981-01-01
A quadratically convergent formulation of the MCSCF method using Fock operators is presented. Among its advantages the present formulation is quadratically convergent unlike the earlier ones based on Fock operators. In contrast to other quadratically convergent schemes as well as the one based on generalized Brillouin's theorem, this method leads easily to a hybrid scheme where the weakly coupled orbitals (such as the core) are handled purely by Fock equations, while the rest of the orbitals are treated by a quadratically convergent approach with a truncated virtual space obtained by the use of the corresponding Fock equations
Series expansions of the density of states in SU(2) lattice gauge theory
International Nuclear Information System (INIS)
Denbleyker, A.; Du, Daping; Liu, Yuzhi; Meurice, Y.; Velytsky, A.
2008-01-01
We calculate numerically the density of states n(S) for SU(2) lattice gauge theory on L 4 lattices [S is the Wilson's action and n(S) measures the relative number of ways S can be obtained]. Small volume dependences are resolved for small values of S. We compare ln(n(S)) with weak and strong coupling expansions. Intermediate order expansions show a good overlap for values of S corresponding to the crossover. We relate the convergence of these expansions to those of the average plaquette. We show that, when known logarithmic singularities are subtracted from ln(n(S)), expansions in Legendre polynomials appear to converge and could be suitable to determine the Fisher's zeros of the partition function.
Longitudinal expansion of field line dipolarization
Saka, O.; Hayashi, K.
2017-11-01
We examine the substorm expansions that started at 1155 UT 10 August 1994 in the midnight sector focusing on the longitudinal (eastward) expansion of field line dipolarization in the auroral zone. Eastward expansion of the dipolarization region was observed in all of the H, D, and Z components. The dipolarization that started at 1155 UT (0027 MLT) from 260° of geomagnetic longitude (CMO) expanded to 351°(PBQ) in about 48 min. The expansion velocity was 0.03-0.04°/s, or 1.9 km/s at 62°N of geomagnetic latitude. The dipolarization region expanding to the east was accompanied by a bipolar event at the leading edge of the expansion in latitudes equatorward of the westward electrojet (WEJ). In the midnight sector at the onset meridian, the Magnetospheric Plasma Analyzer (MAP) on board geosynchronous satellite L9 measured electrons and ions between 10 eV and 40 keV. We conclude from the satellite observations that this dipolarization was characterized by the evolution of temperature anisotropies, an increase of the electron and ion temperatures, and a rapid change in the symmetry axis of the temperature tensor. The field line dipolarization and its longitudinal expansion were interpreted in terms of the slow MHD mode triggered by the current disruption. We propose a new magnetosphere-ionosphere coupling (MI-coupling) mechanism based on the scenario that transmitted westward electric fields from the magnetosphere in association with expanding dipolarization produced electrostatic potential (negative) in the ionosphere through differences in the mobility of collisional ions and collisionless electrons. The field-aligned currents that emerged from the negative potential region are arranged in a concentric pattern around the negative potential region, upward toward the center and downward on the peripheral.
Dimensional expansion for the Ising limit of quantum field theory
International Nuclear Information System (INIS)
Bender, C.M.; Boettcher, S.
1993-01-01
A recently proposed technique, called dimensional expansion, uses the space-time dimension D as an expansion parameter to extract nonperturbative results in quantum field theory. Here we apply dimensional-expansion methods to examine the Ising limit of a self-interacting scalar field theory. We compute the first few coefficients in the dimensional expansion of γ 2n , the renormalized 2n-point Green's function at zero momentum, for n=2, 3, 4, and 5. Because the exact results for γ 2n are known at D=1 we can compare the predictions of the dimensional expansion at this value of D. We find typical accuracies of less than 5%. The radius of convergence of the dimensional expansion for γ 2n appears to be 2n/(n-1). As a function of the space-time dimension D, γ 2n appears to rise monotonically with increasing D and we conjecture that it becomes infinite at D=2n/(n-1). We presume that for values of D greater than this critical value γ 2n vanishes identically because the corresponding φ 2n scalar quantum field theory is free for D>2n/(n-1)
A matched expansion approach to practical self-force calculations
International Nuclear Information System (INIS)
Anderson, Warren G; Wiseman, Alan G
2005-01-01
We discuss a practical method of computing the self-force on a particle moving through a curved spacetime. This method involves two expansions to calculate the self-force, one arising from the particle's immediate past and the other from the more distant past. The expansion in the immediate past is a covariant Taylor series and can be carried out for all geometries. The more distant expansion is a mode sum, and may be carried out in those cases where the wave equation for the field mediating the self-force admits a mode expansion of the solution. In particular, this method can be used to calculate the gravitational self-force for a particle of mass μ orbiting a black hole of mass M to order μ 2 , provided μ/M << 1. We discuss how to use these two expansions to construct a full self-force, and in particular investigate criteria for matching the two expansions. As with all methods of computing self-forces for particles moving in black hole spacetimes, one encounters considerable technical difficulty in applying this method; nevertheless, it appears that the convergence of each series is good enough that a practical implementation may be plausible
Expansions for Coulomb wave functions
Boersma, J.
1969-01-01
In this paper we derive a number of expansions for Whittaker functions, regular and irregular Coulomb wave functions. The main result consists of a new expansion for the irregular Coulomb wave functions of orders zero and one in terms of regular Coulomb wave functions. The latter expansions are
Societal response to nanotechnology: converging technologies–converging societal response research?
Ronteltap, A.; Fischer, A.R.H.; Tobi, H.
2011-01-01
Nanotechnology is an emerging technology particularly vulnerable to societal unrest, which may hinder its further development. With the increasing convergence of several technological domains in the field of nanotechnology, so too could convergence of social science methods help to anticipate
Self-similar dynamic converging shocks - I. An isothermal gas sphere with self-gravity
Lou, Yu-Qing; Shi, Chun-Hui
2014-07-01
We explore novel self-similar dynamic evolution of converging spherical shocks in a self-gravitating isothermal gas under conceivable astrophysical situations. The construction of such converging shocks involves a time-reversal operation on feasible flow profiles in self-similar expansion with a proper care for the increasing direction of the specific entropy. Pioneered by Guderley since 1942 but without self-gravity so far, self-similar converging shocks are important for implosion processes in aerodynamics, combustion, and inertial fusion. Self-gravity necessarily plays a key role for grossly spherical structures in very broad contexts of astrophysics and cosmology, such as planets, stars, molecular clouds (cores), compact objects, planetary nebulae, supernovae, gamma-ray bursts, supernova remnants, globular clusters, galactic bulges, elliptical galaxies, clusters of galaxies as well as relatively hollow cavity or bubble structures on diverse spatial and temporal scales. Large-scale dynamic flows associated with such quasi-spherical systems (including collapses, accretions, fall-backs, winds and outflows, explosions, etc.) in their initiation, formation, and evolution are likely encounter converging spherical shocks at times. Our formalism lays an important theoretical basis for pertinent astrophysical and cosmological applications of various converging shock solutions and for developing and calibrating numerical codes. As examples, we describe converging shock triggered star formation, supernova explosions, and void collapses.
1999-11-03
increases in the posterior and anterior implants of 0.42 mm/year and 0,14 mm/year, respectively. Korn •je and Baumrind also found no evidence to...0.23 mm/year, respectively. Also reporting asymmetric growth of the maxilla, Bjork and Skieller,34 and Korn and Baumrind observed posterior midpalatal...Skieller V. Growth in width of the maxilla studied by the implant method. Scand J Plast Reconstr Surg 1974;8:26-33. 35. Korn EL, Baumrind S
Temporal Convergence for Knowledge Management
Directory of Open Access Journals (Sweden)
Christopher Phillip Martin
2008-05-01
Full Text Available Time and knowledge have tended to be conceptualised in conventional knowledge management systems as either ‘timeless’ recordings of procedures, or time-stamped records of past events and states. The concept of temporal convergence was previously developed to help apply knowledge-management theory to complex military processes such as commander’s intent, shared situation awareness, and self-synchronisation. This paper clarifies the concept and introduces several others in forming a framework to assist discussion and exploration of the types of knowledge required for complex endeavours, such as warfighting, characterised by opposition and uncertainty. The approach is grounded in a pragmatist philosophy and constructivist epistemology. Argument proceeds along mathematical lines from a basis that the types of knowledge most valuable to goal-directed agents in uncertain environments can be modelled as directed graph topologies. The framework is shown to be useful in describing and reasoning about the knowledge requirements and prerequisites for distributed decision-making through the sharing of situational knowledge and common intentions, with practical application to the planning and execution of operations. To the designers of knowledge management systems seeking to address this space, it presents a challenge that cannot be addressed merely by construction, storage, search and retrieval of documents and records pertaining to the past.
Escalated convergent artificial bee colony
Jadon, Shimpi Singh; Bansal, Jagdish Chand; Tiwari, Ritu
2016-03-01
Artificial bee colony (ABC) optimisation algorithm is a recent, fast and easy-to-implement population-based meta heuristic for optimisation. ABC has been proved a rival algorithm with some popular swarm intelligence-based algorithms such as particle swarm optimisation, firefly algorithm and ant colony optimisation. The solution search equation of ABC is influenced by a random quantity which helps its search process in exploration at the cost of exploitation. In order to find a fast convergent behaviour of ABC while exploitation capability is maintained, in this paper basic ABC is modified in two ways. First, to improve exploitation capability, two local search strategies, namely classical unidimensional local search and levy flight random walk-based local search are incorporated with ABC. Furthermore, a new solution search strategy, namely stochastic diffusion scout search is proposed and incorporated into the scout bee phase to provide more chance to abandon solution to improve itself. Efficiency of the proposed algorithm is tested on 20 benchmark test functions of different complexities and characteristics. Results are very promising and they prove it to be a competitive algorithm in the field of swarm intelligence-based algorithms.
Europe of energy: convergencies - complexity
International Nuclear Information System (INIS)
Chevalier, J.M. and others
2001-01-01
This issue of 'Economies et Societes' journal comprises 16 articles dealing with the evolution of European energy markets: the security of European petroleum supplies (P.R. Bauquis); the security of European natural gas supplies (J.M. Dauger); an empirical analysis of the power prices convergence in the European union (J.A. Vega-Cervera, A. Jurado-Malaga); the integration of European power markets, from the juxtaposition of national market to the establishment of a regional market (D. Finon); the fusions-acquisitions in the energy sector and the globalization impact (C.A. Michalet); the reorganization of power economics and the share of right (M.A. Frison-Roche); the European industry facing the new economy (J.M. Chevalier); the confidence stake of the traditional power operators (Y. Benamour, A. Bonanni); status and prospects of gas prices in continental Europe (G. Bellec); the gas and power transport challenges and the access charges fixing (L. David, J. Percebois); the strategic challenges of underground storage in the new European gas context (B. Esnault); stranded costs and deregulation of power networks: some questions raised by the US experience (J. Bezzina); natural gas in Europe and the emergence of spot markets and trading hubs (G. Heyvaert); the competitiveness of the power exchange market of the Netherlands (F. Boisseleau); setting up and de-regulated trades in European markets (H. Geman); the Californian power market (P.L. Joskow). (J.S.)
DEFF Research Database (Denmark)
Kolbæk, Ditte; Lundh Snis, Ulrika
Abstract: This paper analyses an online community of master’s students taking a course in ICT and organisational learning. The students initiated and facilitated an educational design for organisational learning called Proactive Review in the organisation where they are employed. By using an online...... discussion forum on Google groups, they created new ways of reflecting and learning. We used netnography to select qualitative postings from the online community and expansive learning concepts for data analysis. The findings show how students changed practices of organisational learning...
Load regulating expansion fixture
International Nuclear Information System (INIS)
Wagner, L.M.; Strum, M.J.
1998-01-01
A free standing self contained device for bonding ultra thin metallic films, such as 0.001 inch beryllium foils is disclosed. The device will regulate to a predetermined load for solid state bonding when heated to a bonding temperature. The device includes a load regulating feature, whereby the expansion stresses generated for bonding are regulated and self adjusting. The load regulator comprises a pair of friction isolators with a plurality of annealed copper members located there between. The device, with the load regulator, will adjust to and maintain a stress level needed to successfully and economically complete a leak tight bond without damaging thin foils or other delicate components. 1 fig
The long road to convergence and back. Convergence and crossmedia journalism at Dutch Newsmedia
Tameling, Klaske; Broersma, Marcel
2012-01-01
KLASKE TAMELING & MARCEL BROERSMA The long road to convergence and back. Convergence and crossmedia journalism at Dutch Newsmedia Since the end of the twentieth century, convergence and cross-media journalism are concepts that are widely used to guide the future of journalism world wide. This study
Frequency response functions for nonlinear convergent systems
Pavlov, A.V.; Wouw, van de N.; Nijmeijer, H.
2007-01-01
Convergent systems constitute a practically important class of nonlinear systems that extends the class of asymptotically stable linear time-invariant systems. In this note, we extend frequency response functions defined for linear systems to nonlinear convergent systems. Such nonlinear frequency
Beyond Brainstorming: Exploring Convergence in Teams
DEFF Research Database (Denmark)
Seeber, Isabella; de Vreede, Gert-Jan; Maier, Ronald
2017-01-01
Collaborative brainstorming is often followed by a convergence activity where teams extract the most promising ideas on a useful level of detail from the brainstorming results. Contrary to the wealth of research on electronic brainstorming, there is a dearth of research on convergence. We used...
Explaining convergence of oecd welfare states
DEFF Research Database (Denmark)
Schmitt, C.; Starke, Peter
2011-01-01
of conditional convergence helps to both better describe and explain the phenomenon. By applying error correction models, we examine conditional convergence of various types of social expenditure in 21 OECD countries between 1980 and 2005. Our empirical findings go beyond the existing literature in two respects...
New concurrent iterative methods with monotonic convergence
Energy Technology Data Exchange (ETDEWEB)
Yao, Qingchuan [Michigan State Univ., East Lansing, MI (United States)
1996-12-31
This paper proposes the new concurrent iterative methods without using any derivatives for finding all zeros of polynomials simultaneously. The new methods are of monotonic convergence for both simple and multiple real-zeros of polynomials and are quadratically convergent. The corresponding accelerated concurrent iterative methods are obtained too. The new methods are good candidates for the application in solving symmetric eigenproblems.
Directory of Open Access Journals (Sweden)
Hyeokseong Lee
2016-10-01
Full Text Available Firms in high-technology industries have faced great technological and market uncertainty and volatility in the past few decades. In order to be competitive and sustainable in this environment, firms have been pursuing technological innovation, product differentiation, vertical integration, and alliances, which eventually drive industry convergence, defined as the process of blurring boundaries between previously distinct industries. Although industry convergence has greatly affected industrial structure and the economy, little research has investigated this phenomenon, especially its diffusion patterns; thus, it is still unclear which industries are converging more rapidly or have a higher potential for convergence. This paper explores these issues by investigating industry convergence in U.S. high-technology industries, using a large set of newspaper articles from 1987 to 2012. We perform a co-occurrence-based analysis to obtain information on industry convergence and estimate its diffusion patterns using an internal-influence logistic model. We find heterogeneous diffusion patterns, depending on convergent-industry pairs and their wide dispersion. In addition, we find that the potential degree of industry convergence is significantly negatively associated with its growth rate, which indicates that a great deal of time will be required for industry convergence between high-technology industries with this high potential to achieve a high degree of convergence.
Correlation Analysis between Nominal and Real Convergence. The Romanian Case
Directory of Open Access Journals (Sweden)
Marius-Corneliu Marinas
2006-05-01
Full Text Available This study aims to analyze the sources of the correlation between the nominal and real convergence, as well as the impact of the macroeconomic politics on it. The perspective of Euro adoption will impose stricter management of monetary and budgetary politics, which will affect negatively the catching up process of the economic delays given the lack of higher economic flexibility. This enables a more rapid adjustment of the economy to some persistent shocks as a result of applying growth aggregate supply politics.
Correlation Analysis between Nominal and Real Convergence. The Romanian Case
Directory of Open Access Journals (Sweden)
Marius-Corneliu Marinas
2006-03-01
Full Text Available This study aims to analyze the sources of the correlation between the nominal and real convergence, as well as the impact of the macroeconomic politics on it. The perspective of Euro adoption will impose stricter management of monetary and budgetary politics, which will affect negatively the catching up process of the economic delays given the lack of higher economic flexibility. This enables a more rapid adjustment of the economy to some persistent shocks as a result of applying growth aggregate supply politics.
Thermal expansion of granite rocks
International Nuclear Information System (INIS)
Stephansson, O.
1978-04-01
The thermal expansion of rocks is strongly controlled by the thermal expansion of the minerals. The theoretical thermal expansion of the Stripa Granite is gound to be 21 . 10 -6 [deg C] -1 at 25 deg C and 38 . 10 -6 [deg C] -1 at 400 deg C. The difference in expansion for the rock forming minerals causes micro cracking at heating. The expansion due to micro cracks is found to be of the same order as the mineral expansion. Most of the micro cracks will close at pressures of the order of 10 - 20 MPa. The thermal expansion of a rock mass including the effect of joints is determined in the pilot heater test in the Stripa Mine
Energy Technology Data Exchange (ETDEWEB)
Froschauer, K J
1993-01-01
A study of the development of five provincial hydroelectric utilities in Canada indicates that power companies and the state invited manufacturers to use hydroelectricity and natural resources in order to diversify provincial economies. These hydro expansions also show that utilities and government designed hydro projects to serve continental requirements; serving both objectives became problematic. It is argued that when the Canadian state and firms such as utilities use hydro expansions to serve both continentalism and industrialization, then at best they foster dependent industrialization and staple processing. At worst, they overbuild the infrastructure to generate provincial surplus energy for continental, rather than national, integration. Hydro developments became subject to state intervention in Canada mainly through the failures of private utilities to provide power for the less-lucrative industrial markets within provincial subregions. Although the state and utilities invited foreign firms to manufacture hydro equipment within the provinces and others to use electricity to diversify production beyond resource processing, such a diversification did not occur. Since 1962, ca 80% of industrial energy was used to semi-process wood-derived products, chemicals, and metals. The idea for a national power network became undermined by interprovincial political-economic factors and since 1963, the federal national/continential power policy prevailed. 187 refs., 6 figs., 52 tabs.
International Nuclear Information System (INIS)
Vogeleer, J. P.
1985-01-01
The expansion of the primary tubes or sleeves of the steam generator of a nuclear reactor plant are measured while the tubes or sleeves are being expanded. A primary tube or sleeve is expanded by high pressure of water which flows through a channel in an expander body. The water is supplied through an elongated conductor and is introduced through a connector on the shank connected to the conductor at its outer end. A wire extends through the mandrel and through the conductor to the end of the connector. At its inner end the wire is connected to a tapered pin which is subject to counteracting forces produced by the pressure of the water. The force on the side where the wire is connected to the conductor is smaller than on the opposite side. The tapered pin is moved in the direction of the higher force and extrudes the wire outwardly of the conductor. The tapered surface of the tapered pin engages transverse captive plungers which are maintained in engagement with the expanding tube or sleeve as they are moved outwardly by the tapered pin. The wire and the connector extend out of the generator and, at its outer end, the wire is connected to an indicator which measures the extent to which the wire is moved by the tapered pin, thus measuring the expansion of the tube or sleeve as it progresses
Convergence problems of Coulomb and multipole sums in crystals
International Nuclear Information System (INIS)
Kholopov, Evgenii V
2004-01-01
Different ways of calculating Coulomb and dipole sums over crystal lattices are analyzed comparatively. It is shown that the currently alleged disagreement between various approaches originates in ignoring the requirement for the self-consistency of surface conditions, which are of fundamental importance due to the long-range nature of the bulk interactions that these sums describe. This is especially true of surfaces arising when direct sums for infinite translation-invariant structures are truncated. The charge conditions for actual surfaces being self-consistently adjusted to the bulk state are formally the same as those on the truncation surface, consistent with the concept of the thermodynamic limit for the bulk-state absolute equilibrium and with the fact that the surface energy contribution in this case is, naturally, statistically small compared to the bulk contribution. Two-point multipole expansions are briefly discussed, and the problems associated with the boundary of their convergence circle are pointed out. (reviews of topical problems)
Data Convergence - An Australian Perspective
Allen, S. S.; Howell, B.
2012-12-01
Coupled numerical physical, biogeochemical and sediment models are increasingly being used as integrators to help understand the cumulative or far field effects of change in the coastal environment. This reliance on modeling has forced observations to be delivered as data streams ingestible by modeling frameworks. This has made it easier to create near real-time or forecasting models than to try to recreate the past, and has lead in turn to the conversion of historical data into data streams to allow them to be ingested by the same frameworks. The model and observation frameworks under development within Australia's Commonwealth and Industrial Research Organisation (CSIRO) are now feeding into the Australian Ocean Data Network's (AODN's) MARine Virtual Laboratory (MARVL) . The sensor, or data stream, brokering solution is centred around the "message" and all data flowing through the gateway is wrapped as a message. Messages consist of a topic and a data object and their routing through the gateway to pre-processors and listeners is determined by the topic. The Sensor Message Gateway (SMG) method is allowing data from different sensors measuring the same thing but with different temporal resolutions, units or spatial coverage to be ingested or visualized seamlessly. At the same time the model output as a virtual sensor is being explored, this again being enabled by the SMG. It is only for two way communications with sensor that rigorous adherence to standards is needed, by accepting existing data in less than ideal formats, but exposing them though the SMG we can move a step closer to the Internet Of Things by creating an Internet of Industries where each vested interest can continue with business as usual, contribute to data convergence and adopt more open standards when investment seems appropriate to that sector or business.Architecture Overview
On the convergence of finite state mean-field games through Γ-convergence
Ferreira, Rita C.; Gomes, Diogo A.
2014-01-01
In this study, we consider the long-term convergence (trend toward an equilibrium) of finite state mean-field games using Γ-convergence. Our techniques are based on the observation that an important class of mean-field games can be viewed as the Euler-Lagrange equation of a suitable functional. Therefore, using a scaling argument, one can convert a long-term convergence problem into a Γ-convergence problem. Our results generalize previous results related to long-term convergence for finite state problems. © 2014 Elsevier Inc.
On the convergence of finite state mean-field games through Γ-convergence
Ferreira, Rita C.
2014-10-01
In this study, we consider the long-term convergence (trend toward an equilibrium) of finite state mean-field games using Γ-convergence. Our techniques are based on the observation that an important class of mean-field games can be viewed as the Euler-Lagrange equation of a suitable functional. Therefore, using a scaling argument, one can convert a long-term convergence problem into a Γ-convergence problem. Our results generalize previous results related to long-term convergence for finite state problems. © 2014 Elsevier Inc.
Institute of Scientific and Technical Information of China (English)
Shen Diao; Lan Ju
2017-01-01
In the process of meida Convergence,many researchers paid excessive attention to media technology,industry and management,and ignored the culture dimensions of media convergence.Therefore,to transcend media convergence technology,industrial thinking and more to the particularity attach importance to cultural media,it is a right way to achieve media convergence.But in the context of China's culture,media convergence should value the cultural uniqueness and the imbalance of the realistic problems,to reach innovation and breakthrough.
Convergent Power Series of sech(x and Solutions to Nonlinear Differential Equations
Directory of Open Access Journals (Sweden)
U. Al Khawaja
2018-01-01
Full Text Available It is known that power series expansion of certain functions such as sech(x diverges beyond a finite radius of convergence. We present here an iterative power series expansion (IPS to obtain a power series representation of sech(x that is convergent for all x. The convergent series is a sum of the Taylor series of sech(x and a complementary series that cancels the divergence of the Taylor series for x≥π/2. The method is general and can be applied to other functions known to have finite radius of convergence, such as 1/(1+x2. A straightforward application of this method is to solve analytically nonlinear differential equations, which we also illustrate here. The method provides also a robust and very efficient numerical algorithm for solving nonlinear differential equations numerically. A detailed comparison with the fourth-order Runge-Kutta method and extensive analysis of the behavior of the error and CPU time are performed.
Fox, Charles W; Wagner, James D; Cline, Sara; Thomas, Frances Ann; Messina, Frank J
2009-05-01
Independent populations subjected to similar environments often exhibit convergent evolution. An unresolved question is the frequency with which such convergence reflects parallel genetic mechanisms. We examined the convergent evolution of egg-laying behavior in the seed-feeding beetle Callosobruchus maculatus. Females avoid ovipositing on seeds bearing conspecific eggs, but the degree of host discrimination varies among geographic populations. In a previous experiment, replicate lines switched from a small host to a large one evolved reduced discrimination after 40 generations. We used line crosses to determine the genetic architecture underlying this rapid response. The most parsimonious genetic models included dominance and/or epistasis for all crosses. The genetic architecture underlying reduced discrimination in two lines was not significantly different from the architecture underlying differences between geographic populations, but the architecture underlying the divergence of a third line differed from all others. We conclude that convergence of this complex trait may in some cases involve parallel genetic mechanisms.
Directory of Open Access Journals (Sweden)
Paulo Roberto Pelucio Camara
2009-12-01
appliance in patients who underwent surgically assisted rapid maxillary expansion (SARME, as well as the effectiveness of the surgical technique used. The sample was composed of 34 pairs of cast models, of 17 patients - 6 males and 11 females. METHODS: The measurements were performed on cast models, by measuring the changes on the vertical and transversal planes. The surgical procedure used was the lateral osteotomy on maxillary walls with no involvement of the pterygoid blade, osteotomy of nasal spine on dental midline (anterior central incisors, chisel separation of palatine suture, and separation of the nasal septum. The activation was initiated on the third postoperative day, consisting of two activations, one in the morning and another at night. RESULTS: There were statistically significant expansions in the regions of canines, first and second premolars, first molars, and second molars; respectively, 6.03 mm, 9.82 mm, 8.66 mm, 9.72 mm, and 5.67 mm. The evaluation of the behavior of the support teeth of the expansion appliance regarding the inclination of the dental crowns has shown that an asymmetric vestibularization had taken place, because the values found for the first molars were 6.89º (right and 9.56º (left; the values for the first premolars were 4.74º (left and 3.26º (right; this last value was not statistically significant. CONCLUSIONS: The surgical technique used in this research has been shown to be efficient to obtain maxillary transversal alterations, and there was dental-alveolar inclination of the support teeth of the expansion appliance.
Neutron Generation by Laser-Driven Spherically Convergent Plasma Fusion
Ren, G.; Yan, J.; Liu, J.; Lan, K.; Chen, Y. H.; Huo, W. Y.; Fan, Z.; Zhang, X.; Zheng, J.; Chen, Z.; Jiang, W.; Chen, L.; Tang, Q.; Yuan, Z.; Wang, F.; Jiang, S.; Ding, Y.; Zhang, W.; He, X. T.
2017-04-01
We investigate a new laser-driven spherically convergent plasma fusion scheme (SCPF) that can produce thermonuclear neutrons stably and efficiently. In the SCPF scheme, laser beams of nanosecond pulse duration and 1 014- 1 015 W /cm2 intensity uniformly irradiate the fuel layer lined inside a spherical hohlraum. The fuel layer is ablated and heated to expand inwards. Eventually, the hot fuel plasmas converge, collide, merge, and stagnate at the central region, converting most of their kinetic energy to internal energy, forming a thermonuclear fusion fireball. With the assumptions of steady ablation and adiabatic expansion, we theoretically predict the neutron yield Yn to be related to the laser energy EL, the hohlraum radius Rh, and the pulse duration τ through a scaling law of Yn∝(EL/Rh1.2τ0.2 )2.5. We have done experiments at the ShengGuangIII-prototype facility to demonstrate the principle of the SCPF scheme. Some important implications are discussed.
Thermal expansion of coking coals
Energy Technology Data Exchange (ETDEWEB)
Orlik, M.; Klimek, J. (Vyzkumny a Zkusebni Ustav Nova Hut, Ostrava (Czechoslovakia))
1992-12-01
Analyzes expansion of coal mixtures in coke ovens during coking. Methods for measuring coal expansion on both a laboratory and pilot plant scale are comparatively evaluated. The method, developed, tested and patented in Poland by the Institute for Chemical Coal Processing in Zabrze (Polish standard PN-73/G-04522), is discussed. A laboratory device developed by the Institute for measuring coal expansion is characterized. Expansion of black coal from 10 underground mines in the Ostrava-Karvina coal district and from 9 coal mines in the Upper Silesia basin in Poland is comparatively evaluated. Investigations show that coal expansion reaches a maximum for coal types with a volatile matter ranging from 20 to 25%. With increasing volatile matter in coal, its expansion decreases. Coal expansion increases with increasing swelling index. Coal expansion corresponds with coal dilatation. With increasing coal density its expansion increases. Coal mixtures should be selected in such a way that their expansion does not cause a pressure exceeding 40 MPa. 11 refs.
Lancellotti, V.; Hon, de B.P.; Tijhuis, A.G.
2010-01-01
The scattering from a large complex structure comprised of many objects may be efficiently tackled by embedding each object within a bounded domain (brick) which is described through a scattering operator. Upon electromagnetically combining the scattering operators we arrive at an equation which
Seasonal hydroclimatic impacts of Sun Corridor expansion
International Nuclear Information System (INIS)
Georgescu, M; Mahalov, A; Moustaoui, M
2012-01-01
Conversion of natural to urban land forms imparts influence on local and regional hydroclimate via modification of the surface energy and water balance, and consideration of such effects due to rapidly expanding megapolitan areas is necessary in light of the growing global share of urban inhabitants. Based on a suite of ensemble-based, multi-year simulations using the Weather Research and Forecasting (WRF) model, we quantify seasonally varying hydroclimatic impacts of the most rapidly expanding megapolitan area in the US: Arizona’s Sun Corridor, centered upon the Greater Phoenix metropolitan area. Using a scenario-based urban expansion approach that accounts for the full range of Sun Corridor growth uncertainty through 2050, we show that built environment induced warming for the maximum development scenario is greatest during the summer season (regionally averaged warming over AZ exceeds 1 °C). Warming remains significant during the spring and fall seasons (regionally averaged warming over AZ approaches 0.9 °C during both seasons), and is least during the winter season (regionally averaged warming over AZ of 0.5 °C). Impacts from a minimum expansion scenario are reduced, with regionally averaged warming ranging between 0.1 and 0.3 °C for all seasons except winter, when no warming impacts are diagnosed. Integration of highly reflective cool roofs within the built environment, increasingly recognized as a cost-effective option intended to offset the warming influence of urban complexes, reduces urban-induced warming considerably. However, impacts on the hydrologic cycle are aggravated via enhanced evapotranspiration reduction, leading to a 4% total accumulated precipitation decrease relative to the non-adaptive maximum expansion scenario. Our results highlight potentially unintended consequences of this adaptation approach within rapidly expanding megapolitan areas, and emphasize the need for undeniably sustainable development paths that account for
Cluster expansion for abstract polymer models New bounds from an old approach
Fernández, R
2006-01-01
We revisit the classical approach to cluster expansions, based on tree graphs, and establish a new convergence condition that improves those by Koteck\\'y-Preiss and Dobrushin, as we show in some examples. The strategy is to better exploit a well known tree-graph expression, due to Penrose.
Series expansion solution of the Wegner-Houghton renormalisation group equation
International Nuclear Information System (INIS)
Margaritis, A.; Odor, G.; Patkos, A.
1987-11-01
The momentum independent projection of the Wegner-Houghton renormalisation group equation is solved with power series expansion. Convergence rate is analyzed for the n-vector model. Further evidence is presented for the first order nature of the chiral symmetry restoration at finite temperature in QCD with 3 light flavors. (author) 16 refs
The Sturmian expansion: A well-depth-method for orbitals in a deformed potential
International Nuclear Information System (INIS)
Bang, J.M.; Vaagen, J.S.
1980-01-01
The Sturmian expansion method has over the years successfully been used to generate orbitals in a deformed potential. In this paper we review the method in detail including more recent extentions. The convergence properties are discussed in terms of examples of current interest for nucleon-transfer reactions. Comparisons with other methods are also made. (orig.)
Why linear Birch and U/sub s/-U/sub p/ expansions work
International Nuclear Information System (INIS)
Grover, R.
1987-07-01
The equivalence of the Birch-Murnoghan equation to a linear U/sub s/-U/sub p/ equation was illustrated in the previous paper. Here it is shown in a direct manner how the virial theorem boundary localization of valence electron kinetic energy changes lead to the convergence of the Eulerian strain expansion about the zero-pressure state
Pricing early-exercise and discrete barrier options by Shannon wavelet expansions
Maree, S. C.; Ortiz-Gracia, L.; Oosterlee, C. W.
2017-01-01
We present a pricing method based on Shannon wavelet expansions for early-exercise and discretely-monitored barrier options under exponential L,vy asset dynamics. Shannon wavelets are smooth, and thus approximate the densities that occur in finance well, resulting in exponential convergence.
Neutron gain for converging guide tubes
International Nuclear Information System (INIS)
Mildner, D.F.R.
1982-01-01
The method of acceptance diagrams is used to obtain analytical expressions for the neutron gain of a one-dimensional converging guide tube. It is found that the results are more easily expressed by analyzing the acceptance diagram at the exit of the funnel. The results are compared with those for the straight guide. When both guides have the same dimensions at the guide exit, the converging guide has higher transmitted intensity but with greater divergence of the beam. This analytical method is useful to assess the performance of a converging guide, though numerical computations may be required for detailed analysis of a guide system. (orig.)
Convergence analysis of canonical genetic algorithms.
Rudolph, G
1994-01-01
This paper analyzes the convergence properties of the canonical genetic algorithm (CGA) with mutation, crossover and proportional reproduction applied to static optimization problems. It is proved by means of homogeneous finite Markov chain analysis that a CGA will never converge to the global optimum regardless of the initialization, crossover, operator and objective function. But variants of CGA's that always maintain the best solution in the population, either before or after selection, are shown to converge to the global optimum due to the irreducibility property of the underlying original nonconvergent CGA. These results are discussed with respect to the schema theorem.
On WKB expansions for Alfven waves in the solar wind
International Nuclear Information System (INIS)
Hollweg, J.V.
1990-01-01
The author reexamines the WKB expansion for toroidal Alfven waves in the solar wind, as described by equations (9) of Heinemann and Olbert (1980). His principal conclusions are as follows: (1) The WKB expansion used by Belcher (1971) and Hollweg (1973) is nonuniformly convergent. (2) Using the method of multiple scales (Nayfeh, 1981), he obtains an expansion which is uniform. (3) The uniform expansion takes into account the small modification to the Alfven wave phase speed due to spatial gradients of the background. (4) Both the uniform and nonuniform expansions reveal that each normal mode has both Elsaesser variables δz + ≠ 0 and δz - ≠ 0. Thus if δz - corresponds to the outgoing mode in a homogeneous background, an observation of δz + ≠ 0 does not necessarily imply the presence of the inward propagating mode, as is commonly assumed. (5) Even at the Alfven critical point (where V = υ A ) he finds that δz + ≠ 0. Thus incompressible MHD turbulence, which requires both δz + ≠ 0 and δz - ≠ 0, can proceed at the Alfven critical point (cf. Roberts, 1989). (6) With very few exceptions, the predictions of these calculations do not agree with recent observations (Marsch and Tu, 1990) of the power spectra of δz + and δz - in the solar wind. Thus the evolution of Alfven waves in the solar wind is governed by dynamics not included in the Heinemann and Olbert equations
Principles of Thermal Expansion in Feldspars
Hovis, Guy; Medford, Aaron; Conlon, Maricate; Tether, Allison; Romanoski, Anthony
2010-05-01
bridging Al-O-Si oxygens, (C) plagioclase (11,12,13) and (D) Ba-K feldspars (12) where coupled substitution across the series produces expansion behavior that rapidly transitions from one control to the other. Generally, thermal expansion coefficients vary linearly as functions of room-temperature volume between the relevant end members. Thus, the thermal expansion of any feldspar can be estimated simply from knowledge of its chemical system and room-temperature volume. References cited: (1) Hovis, Morabito, Spooner, Mott, Person, Henderson, Roux & Harlov (2008) American Mineralogist 93, 1568-1573. (2) Hovis & Graeme-Barber (1997) American Mineralogist 82, 158-164. (3) Hovis, Brennan, Keohane & Crelling (1999) The Canadian Mineralogist 37, 701-709. (4) Henderson (1984) Progress in Experimental Petrology, N.E.R.C. Report 6, 78-83. (5) Benna, Tribaudino & Bruno (1999) American Mineralogist 84, 120-129. (6) Lowenstein (1954) American Mineralogist 39, 92 -96. (7) Megaw, Kempster & Radosolovich (1962) Acta Crystallographica 15, 1017-1035. (8) Newham & Megaw (1960) Acta Crystallographica 13, 303-312. (9) Pauling (1929) Journal of the American Chemical Society 51, 1010-1026. (10) Gibbs, Rosso, Cox & Boisen (2003) Physics and Chemistry of Minerals 30, 317-320. (11) Grundy & Brown (1974) In The Feldspars, Eds. MacKenzie & Zussman, 163-173. (12) Hovis, Medford, Conlon, Tether & Romanoski (in review) American Mineralogist. (13) Tribaudino, Angel, Camara, Nestola, Pasqual, & Margiolaki (in review) Contributions to Mineralogy and Petrology.
Monte Carlo methods for flux expansion solutions of transport problems
International Nuclear Information System (INIS)
Spanier, J.
1999-01-01
Adaptive Monte Carlo methods, based on the use of either correlated sampling or importance sampling, to obtain global solutions to certain transport problems have recently been described. The resulting learning algorithms are capable of achieving geometric convergence when applied to the estimation of a finite number of coefficients in a flux expansion representation of the global solution. However, because of the nonphysical nature of the random walk simulations needed to perform importance sampling, conventional transport estimators and source sampling techniques require modification to be used successfully in conjunction with such flux expansion methods. It is shown how these problems can be overcome. First, the traditional path length estimators in wide use in particle transport simulations are generalized to include rather general detector functions (which, in this application, are the individual basis functions chosen for the flus expansion). Second, it is shown how to sample from the signed probabilities that arise as source density functions in these applications, without destroying the zero variance property needed to ensure geometric convergence to zero error
Thermal expansion of beryllium oxide
International Nuclear Information System (INIS)
Solodukhin, A.V.; Kruzhalov, A.V.; Mazurenko, V.G.; Maslov, V.A.; Medvedev, V.A.; Polupanova, T.I.
1987-01-01
Precise measurements of temperature dependence of the coefficient of linear expansion in the 22-320 K temperature range on beryllium oxide monocrystals are conducted. A model of thermal expansion is suggested; the range of temperature dependence minimum of the coefficient of thermal expansion is well described within the frames of this model. The results of the experiment may be used for investigation of thermal stresses in crystals
A two-parameter family of double-power-law biorthonormal potential-density expansions
Lilley, Edward J.; Sanders, Jason L.; Evans, N. Wyn
2018-05-01
We present a two-parameter family of biorthonormal double-power-law potential-density expansions. Both the potential and density are given in closed analytic form and may be rapidly computed via recurrence relations. We show that this family encompasses all the known analytic biorthonormal expansions: the Zhao expansions (themselves generalizations of ones found earlier by Hernquist & Ostriker and by Clutton-Brock) and the recently discovered Lilley et al. (2017a) expansion. Our new two-parameter family includes expansions based around many familiar spherical density profiles as zeroth-order models, including the γ models and the Jaffe model. It also contains a basis expansion that reproduces the famous Navarro-Frenk-White (NFW) profile at zeroth order. The new basis expansions have been found via a systematic methodology which has wide applications in finding other new expansions. In the process, we also uncovered a novel integral transform solution to Poisson's equation.
Rapid-Cycling Bubble-Chamber, details
CERN PhotoLab
1980-01-01
Parts of the hydraulic expansion system of the Rapid-Cycling Bubble-Chamber (RCBC). RCBC was the largest of 3 rapid-cycling bubble-chambers (the others were LEBC and HOLEBC), used as target- and vertex-detectors within the European Hybrid Spectrometer (EHS) in the SPS North Area (EHN1). RCBC contained 250 l of liquid hydrogen and was located inside a 3 T superconducting magnet. It was designed for 30 expansions/s (100 times faster than BEBC), the system shown here allowed 50 expansions/s. RCBC operated from 1981 to 1983 for experiments NA21, NA22 and NA23 at a rate of 15 expansions/s, clocking up a total of over 4 million. In the rear, at left, is bearded Lucien Veillet; Augustin Didona is at the right. See also 8001009. The installation of the piston assembly in the RCBC chamber body is shown in the Annual Report 1980, p.65.
Strategic business transformation through technology convergence
DEFF Research Database (Denmark)
Agarwal, Nivedita; Brem, Alexander
2015-01-01
-time intelligence. This paper presents the case of General Electric (GE) and studies the various transitional phases and transformation dimensions that GE is experiencing, to manage this technology convergence. The evaluation of GE's experience indicates that convergence-related business transformation is nonlinear......Technology adoption is crucial for an organisation to remain competitive in the marketplace. Traditionally, two technologies - operational technology (OT) and information technology (IT) - have operated independently from one another; however, technological advancements that businesses...... are experiencing have increased the overlap and convergence of these two areas. Industrial organisations are investing heavily in the integration and alignment of these technologies and expect to benefit in several ways from this convergence, such as through increased productivity, reduction in cost, and real...
Convergent Validity of Four Innovativeness Scales.
Goldsmith, Ronald E.
1986-01-01
Four scales of innovativeness were administered to two samples of undergraduate students: the Open Processing Scale, Innovativeness Scale, innovation subscale of the Jackson Personality Inventory, and Kirton Adaption-Innovation Inventory. Intercorrelations indicated the scales generally exhibited convergent validity. (GDC)
A class of convergent neural network dynamics
Fiedler, Bernold; Gedeon, Tomáš
1998-01-01
We consider a class of systems of differential equations in Rn which exhibits convergent dynamics. We find a Lyapunov function and show that every bounded trajectory converges to the set of equilibria. Our result generalizes the results of Cohen and Grossberg (1983) for convergent neural networks. It replaces the symmetry assumption on the matrix of weights by the assumption on the structure of the connections in the neural network. We prove the convergence result also for a large class of Lotka-Volterra systems. These are naturally defined on the closed positive orthant. We show that there are no heteroclinic cycles on the boundary of the positive orthant for the systems in this class.
Divergence and convergence in nutrition science
Penders, Bart; Spruit, Shannon L.; Sikkema, Jan; Maat, Jan; Schuurbiers, Daan
2015-01-01
Nutrigenomics diverged from mainstream nutrition science, ideologically, instrumentally and culturally, due to the establishment of a protective niche. That protection is fading. This article chronicles a case in which convergence between nutrigenomics and nutrition science is pursued. Here we
Advances and Challenges in Convergent Communication Networks
DEFF Research Database (Denmark)
Toral-Cruz, Homero; Mihovska, Albena
2017-01-01
Welcome to this special issue of Wireless Personal Communications on Advances and Challenges in Convergent Communication Networks. The main purpose of this special issue is to present new progresses and challenges in convergent networks. Communication networks play an important role in our daily...... life because they allow communicating and sharing contents between heterogeneous nodes around the globe. The emergence of multiple network architectures and emerging technologies have resulted in new applications and services over a heterogeneous network. This heterogeneous network has undergone...... significant challenges in recent years, such as the evolution to a converged network with the capability to support multiple services, while maintaining a satisfactory level of QoE/QoS, security, efficiency and trust. The special issue on Advances and Challenges in Convergent Communication Networks...
Testing the Conditional Convergence Hypothesis for Pakistan
Directory of Open Access Journals (Sweden)
Sajjad Ahmad Jan (Corresponding Author
2011-09-01
Full Text Available This study investigates for the existence or non-existence of conditional convergence across the provinces of Pakistan. The annual output data from 1973 to 2000 is pooled for the four Pakistani provinces. The cross-sectional specific effects, the time specific effects, the manufacturing output, and the structural variable for aggregate supply or production shocks are used to control the different steady state levels of per capita incomes of thedifferent provinces. The equation for conditional convergence is estimated through generalized least squares (GLS method, after controlling for the different steady states of the provinces. The result shows that the provinces of Pakistan converge to their own respective steady states with a convergence speed of 11% per annum. At the same time manufacturing output is also statistically significant and positively affects the economic growth in the provinces. However the structural variable is not statistically significant.
Estimating the contribution of mortality selection to the East–West German mortality convergence
Vogt, Tobias; Missov, Trifon
2017-01-01
Background: Before German reunification, old-age mortality was considerably higher in East Germany than West Germany but converged quickly afterward. Previous studies attributed this rapid catch-up to improved living conditions. We add to this discussion by quantifying for the first time the impact
Towards converged 5G mobile networks-challenges and current trends
DEFF Research Database (Denmark)
Zakrzewska, Anna; Ruepp, Sarah Renée; Berger, Michael Stübert
2014-01-01
With the rapid development of wireless technologies, the concept of the Fifth Generation (5G) wireless communication system started to emerge and it is foreseen that it will be a result of standards convergence. The expectations towards 5G are set much higher in terms of capacity and maximum thro...
Convergence of Corporate and Information Security
Syed; Rahman, M.; Donahue, Shannon E.
2010-01-01
As physical and information security boundaries have become increasingly blurry many organizations are experiencing challenges with how to effectively and efficiently manage security within the corporate. There is no current standard or best practice offered by the security community regarding convergence; however many organizations such as the Alliance for Enterprise Security Risk Management (AESRM) offer some excellent suggestions for integrating a converged security program. This paper rep...
Convergence in Global Food Demand and Delivery
Regmi, Anita; Takeshima, Hiroyuki; Unnevehr, Laurian J.
2008-01-01
Using food expenditures and food sales data over 1990-2004, this report examines whether food consumption and delivery trends are converging across 47 high- and middle-income countries. Middle-income countries, such as China and Mexico, appear to be following trends in high-income countries, measured across several dimensions of food system growth and change. Convergence is apparent in most important food expenditure categories and in indicators of food system modernization such as supermarke...
Convergence Science in a Nano World
Cady, Nathaniel
2013-01-01
Convergence is a new paradigm that brings together critical advances in the life sciences, physical sciences and engineering. Going beyond traditional “interdisciplinary” studies, “convergence” describes the culmination of truly integrated research and development, yielding revolutionary advances in both scientific research and new technologies. At its core, nanotechnology embodies these elements of convergence science by bringing together multiple disciplines with the goal of creating innova...
Global Convergence of a Modified LS Method
Directory of Open Access Journals (Sweden)
Liu JinKui
2012-01-01
Full Text Available The LS method is one of the effective conjugate gradient methods in solving the unconstrained optimization problems. The paper presents a modified LS method on the basis of the famous LS method and proves the strong global convergence for the uniformly convex functions and the global convergence for general functions under the strong Wolfe line search. The numerical experiments show that the modified LS method is very effective in practice.
International Convergence on Geoscience Cyberinfrastructure
Allison, M. L.; Atkinson, R.; Arctur, D. K.; Cox, S.; Jackson, I.; Nativi, S.; Wyborn, L. A.
2012-04-01
There is growing international consensus on addressing the challenges to cyber(e)-infrastructure for the geosciences. These challenges include: Creating common standards and protocols; Engaging the vast number of distributed data resources; Establishing practices for recognition of and respect for intellectual property; Developing simple data and resource discovery and access systems; Building mechanisms to encourage development of web service tools and workflows for data analysis; Brokering the diverse disciplinary service buses; Creating sustainable business models for maintenance and evolution of information resources; Integrating the data management life-cycle into the practice of science. Efforts around the world are converging towards de facto creation of an integrated global digital data network for the geosciences based on common standards and protocols for data discovery and access, and a shared vision of distributed, web-based, open source interoperable data access and integration. Commonalities include use of Open Geospatial Consortium (OGC) and ISO specifications and standardized data interchange mechanisms. For multidisciplinarity, mediation, adaptation, and profiling services have been successfully introduced to leverage the geosciences standards which are commonly used by the different geoscience communities -introducing a brokering approach which extends the basic SOA archetype. Principal challenges are less technical than cultural, social, and organizational. Before we can make data interoperable, we must make people interoperable. These challenges are being met by increased coordination of development activities (technical, organizational, social) among leaders and practitioners in national and international efforts across the geosciences to foster commonalities across disparate networks. In doing so, we will 1) leverage and share resources, and developments, 2) facilitate and enhance emerging technical and structural advances, 3) promote
ANALYSIS OF CONVERGENCE WITHIN THE EUROPEAN UNION SIGMA AND BETA CONVERGENCE
Directory of Open Access Journals (Sweden)
Begu Liviu-Stelian
2010-12-01
Full Text Available Real convergence study began with the development of neoclassical models of growth and especially with the passage of econometric applications of these models. In this paper we present applications of indicators and patterns of convergence on the example of European Union member countries and some current economic impact assessments on European convergence process. This analysis is based on the estimated a- and b convergence and on Markov chains. The study deals with the economic convergence of the European countries and especially the convergence of the EU countries, including Romania. In the end of the study presents several economic scenarios for a faster and easier exit from the current crisis in Romania.
Renormalization group and Mayer expansions
International Nuclear Information System (INIS)
Mack, G.
1984-02-01
Mayer expansions promise to become a powerful tool in exact renormalization group calculations. Iterated Mayer expansions were sucessfully used in the rigorous analysis of 3-dimensional U(1) lattice gauge theory by Goepfert and the author, and it is hoped that they will also be useful in the 2-dimensional nonlinear sigma-model, and elsewhere. (orig.)
Isotropic Negative Thermal Expansion Metamaterials.
Wu, Lingling; Li, Bo; Zhou, Ji
2016-07-13
Negative thermal expansion materials are important and desirable in science and engineering applications. However, natural materials with isotropic negative thermal expansion are rare and usually unsatisfied in performance. Here, we propose a novel method to achieve two- and three-dimensional negative thermal expansion metamaterials via antichiral structures. The two-dimensional metamaterial is constructed with unit cells that combine bimaterial strips and antichiral structures, while the three-dimensional metamaterial is fabricated by a multimaterial 3D printing process. Both experimental and simulation results display isotropic negative thermal expansion property of the samples. The effective coefficient of negative thermal expansion of the proposed models is demonstrated to be dependent on the difference between the thermal expansion coefficient of the component materials, as well as on the circular node radius and the ligament length in the antichiral structures. The measured value of the linear negative thermal expansion coefficient of the three-dimensional sample is among the largest achieved in experiments to date. Our findings provide an easy and practical approach to obtaining materials with tunable negative thermal expansion on any scale.
Renormalization group and mayer expansions
International Nuclear Information System (INIS)
Mack, G.
1984-01-01
Mayer expansions promise to become a powerful tool in exact renormalization group calculations. Iterated Mayer expansions were sucessfully used in the rigorous analysis of 3-dimensional U (1) lattice gauge theory by Gopfert and the author, and it is hoped that they will also be useful in the 2-dimensional nonlinear σ-model, and elsewhere
On summation of perturbation expansions
International Nuclear Information System (INIS)
Horzela, A.
1985-04-01
The problem of the restoration of physical quantities defined by divergent perturbation expansions is analysed. The Pad'e and Borel summability is proved for alternating perturbation expansions with factorially growing coefficients. The proof is based on the methods of the classical moments theory. 17 refs. (author)
The Government Response to the Private Sector Expansion in Poland
Antonowicz, Dominik; Kwiek, Marek; Westerheijden, Donald F.; Boer, Harry; File, Jon; Huisman, Jeroen; Seeber, Marco; Vukasovic, Martina; Westerheijden, Don F.
2017-01-01
One of the trademarks of transformation of Polish higher education is its tumultuous and inconsistent path of development driven by the rapid growth of private sector higher education. Such an expansion has been often described as a ‘sudden, shocking and unplanned’ phenomenon which revolutionized
Bilateral Re-Expansion Pulmonary Oedema– When the Cure Is ...
African Journals Online (AJOL)
Background: Re-expansion pulmonary oedema is a potentially fatal consequence of rapid reexpansion of a lung, which has been collapsed due to a pleural effusion or a pneumothorax. Case Report: We report a very unusual case in which the patient initially developed ipsilateral followed by contralateral pulmonary ...
Evolution of density-dependent movement during experimental range expansions.
Fronhofer, E A; Gut, S; Altermatt, F
2017-12-01
Range expansions and biological invasions are prime examples of transient processes that are likely impacted by rapid evolutionary changes. As a spatial process, range expansions are driven by dispersal and movement behaviour. Although it is widely accepted that dispersal and movement may be context-dependent, for instance density-dependent, and best represented by reaction norms, the evolution of density-dependent movement during range expansions has received little experimental attention. We therefore tested current theory predicting the evolution of increased movement at low densities at range margins using highly replicated and controlled range expansion experiments across multiple genotypes of the protist model system Tetrahymena thermophila. Although rare, we found evolutionary changes during range expansions even in the absence of initial standing genetic variation. Range expansions led to the evolution of negatively density-dependent movement at range margins. In addition, we report the evolution of increased intrastrain competitive ability and concurrently decreased population growth rates in range cores. Our findings highlight the importance of understanding movement and dispersal as evolving reaction norms and plastic life-history traits of central relevance for range expansions, biological invasions and the dynamics of spatially structured systems in general. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.
Generation Expansion Planning Considering Integrating Large-scale Wind Generation
DEFF Research Database (Denmark)
Zhang, Chunyu; Ding, Yi; Østergaard, Jacob
2013-01-01
necessitated the inclusion of more innovative and sophisticated approaches in power system investment planning. A bi-level generation expansion planning approach considering large-scale wind generation was proposed in this paper. The first phase is investment decision, while the second phase is production...... optimization decision. A multi-objective PSO (MOPSO) algorithm was introduced to solve this optimization problem, which can accelerate the convergence and guarantee the diversity of Pareto-optimal front set as well. The feasibility and effectiveness of the proposed bi-level planning approach and the MOPSO...
Possibilities for global governance of converging technologies
Roco, Mihail C.
2008-01-01
The convergence of nanotechnology, modern biology, the digital revolution and cognitive sciences will bring about tremendous improvements in transformative tools, generate new products and services, enable opportunities to meet and enhance human potential and social achievements, and in time reshape societal relationships. This paper focuses on the progress made in governance of such converging, emerging technologies and suggests possibilities for a global approach. Specifically, this paper suggests creating a multidisciplinary forum or a consultative coordinating group with members from various countries to address globally governance of converging, emerging technologies. The proposed framework for governance of converging technologies calls for four key functions: supporting the transformative impact of the new technologies; advancing responsible development that includes health, safety and ethical concerns; encouraging national and global partnerships; and establishing commitments to long-term planning and investments centered on human development. Principles of good governance guiding these functions include participation of all those who are forging or affected by the new technologies, transparency of governance strategies, responsibility of each participating stakeholder, and effective strategic planning. Introduction and management of converging technologies must be done with respect for immediate concerns, such as privacy, access to medical advancements, and potential human health effects. At the same time, introduction and management should also be done with respect for longer-term concerns, such as preserving human integrity, dignity and welfare. The suggested governance functions apply to four levels of governance: (a) adapting existing regulations and organizations; (b) establishing new programs, regulations and organizations specifically to handle converging technologies; (c) building capacity for addressing these issues into national policies and
Possibilities for global governance of converging technologies
International Nuclear Information System (INIS)
Roco, Mihail C.
2008-01-01
The convergence of nanotechnology, modern biology, the digital revolution and cognitive sciences will bring about tremendous improvements in transformative tools, generate new products and services, enable opportunities to meet and enhance human potential and social achievements, and in time reshape societal relationships. This paper focuses on the progress made in governance of such converging, emerging technologies and suggests possibilities for a global approach. Specifically, this paper suggests creating a multidisciplinary forum or a consultative coordinating group with members from various countries to address globally governance of converging, emerging technologies. The proposed framework for governance of converging technologies calls for four key functions: supporting the transformative impact of the new technologies; advancing responsible development that includes health, safety and ethical concerns; encouraging national and global partnerships; and establishing commitments to long-term planning and investments centered on human development. Principles of good governance guiding these functions include participation of all those who are forging or affected by the new technologies, transparency of governance strategies, responsibility of each participating stakeholder, and effective strategic planning. Introduction and management of converging technologies must be done with respect for immediate concerns, such as privacy, access to medical advancements, and potential human health effects. At the same time, introduction and management should also be done with respect for longer-term concerns, such as preserving human integrity, dignity and welfare. The suggested governance functions apply to four levels of governance: (a) adapting existing regulations and organizations; (b) establishing new programs, regulations and organizations specifically to handle converging technologies; (c) building capacity for addressing these issues into national policies and
Possibilities for global governance of converging technologies
Energy Technology Data Exchange (ETDEWEB)
Roco, Mihail C. [National Science Foundation (NSF) (United States)], E-mail: mroco@nsf.gov
2008-01-15
The convergence of nanotechnology, modern biology, the digital revolution and cognitive sciences will bring about tremendous improvements in transformative tools, generate new products and services, enable opportunities to meet and enhance human potential and social achievements, and in time reshape societal relationships. This paper focuses on the progress made in governance of such converging, emerging technologies and suggests possibilities for a global approach. Specifically, this paper suggests creating a multidisciplinary forum or a consultative coordinating group with members from various countries to address globally governance of converging, emerging technologies. The proposed framework for governance of converging technologies calls for four key functions: supporting the transformative impact of the new technologies; advancing responsible development that includes health, safety and ethical concerns; encouraging national and global partnerships; and establishing commitments to long-term planning and investments centered on human development. Principles of good governance guiding these functions include participation of all those who are forging or affected by the new technologies, transparency of governance strategies, responsibility of each participating stakeholder, and effective strategic planning. Introduction and management of converging technologies must be done with respect for immediate concerns, such as privacy, access to medical advancements, and potential human health effects. At the same time, introduction and management should also be done with respect for longer-term concerns, such as preserving human integrity, dignity and welfare. The suggested governance functions apply to four levels of governance: (a) adapting existing regulations and organizations; (b) establishing new programs, regulations and organizations specifically to handle converging technologies; (c) building capacity for addressing these issues into national policies and
Coupling-parameter expansion in thermodynamic perturbation theory.
Ramana, A Sai Venkata; Menon, S V G
2013-02-01
An approach to the coupling-parameter expansion in the liquid state theory of simple fluids is presented by combining the ideas of thermodynamic perturbation theory and integral equation theories. This hybrid scheme avoids the problems of the latter in the two phase region. A method to compute the perturbation series to any arbitrary order is developed and applied to square well fluids. Apart from the Helmholtz free energy, the method also gives the radial distribution function and the direct correlation function of the perturbed system. The theory is applied for square well fluids of variable ranges and compared with simulation data. While the convergence of perturbation series and the overall performance of the theory is good, improvements are needed for potentials with shorter ranges. Possible directions for further developments in the coupling-parameter expansion are indicated.
Experiences using DAKOTA stochastic expansion methods in computational simulations.
Energy Technology Data Exchange (ETDEWEB)
Templeton, Jeremy Alan; Ruthruff, Joseph R.
2012-01-01
Uncertainty quantification (UQ) methods bring rigorous statistical connections to the analysis of computational and experiment data, and provide a basis for probabilistically assessing margins associated with safety and reliability. The DAKOTA toolkit developed at Sandia National Laboratories implements a number of UQ methods, which are being increasingly adopted by modeling and simulation teams to facilitate these analyses. This report disseminates results as to the performance of DAKOTA's stochastic expansion methods for UQ on a representative application. Our results provide a number of insights that may be of interest to future users of these methods, including the behavior of the methods in estimating responses at varying probability levels, and the expansion levels for the methodologies that may be needed to achieve convergence.
A mutually profitable alliance - Asymptotic expansions and numerical computations
Euvrard, D.
Problems including the flow past a wing airfoil at Mach 1, and the two-dimensional flow past a partially immersed body are used to show the advantages of coupling a standard numerical method for the whole domain where everything is of the order of 1, with an appropriate asymptotic expansion in the vicinity of some singular point. Cases more closely linking the two approaches are then considered. In the localized finite element method, the asymptotic expansion at infinity becomes a convergent series and the problem reduces to a variational form. Combined analytical and numerical methods are used in the singularity distribution method and in the various couplings of finite elements and a Green integral representation to design a subroutine to compute the Green function and its derivatives.
Gukelberger, Jan; Kozik, Evgeny; Hafermann, Hartmut
2017-07-01
The dual fermion approach provides a formally exact prescription for calculating properties of a correlated electron system in terms of a diagrammatic expansion around dynamical mean-field theory (DMFT). Most practical implementations, however, neglect higher-order interaction vertices beyond two-particle scattering in the dual effective action and further truncate the diagrammatic expansion in the two-particle scattering vertex to a leading-order or ladder-type approximation. In this work, we compute the dual fermion expansion for the two-dimensional Hubbard model including all diagram topologies with two-particle interactions to high orders by means of a stochastic diagrammatic Monte Carlo algorithm. We benchmark the obtained self-energy against numerically exact diagrammatic determinant Monte Carlo simulations to systematically assess convergence of the dual fermion series and the validity of these approximations. We observe that, from high temperatures down to the vicinity of the DMFT Néel transition, the dual fermion series converges very quickly to the exact solution in the whole range of Hubbard interactions considered (4 ≤U /t ≤12 ), implying that contributions from higher-order vertices are small. As the temperature is lowered further, we observe slower series convergence, convergence to incorrect solutions, and ultimately divergence. This happens in a regime where magnetic correlations become significant. We find, however, that the self-consistent particle-hole ladder approximation yields reasonable and often even highly accurate results in this regime.
Gene Acquisition Convergence between Entomopoxviruses and Baculoviruses
Directory of Open Access Journals (Sweden)
Julien Thézé
2015-04-01
Full Text Available Organisms from diverse phylogenetic origins can thrive within the same ecological niches. They might be induced to evolve convergent adaptations in response to a similar landscape of selective pressures. Their genomes should bear the signature of this process. The study of unrelated virus lineages infecting the same host panels guarantees a clear identification of phyletically independent convergent adaptation. Here, we investigate the evolutionary history of genes in the accessory genome shared by unrelated insect large dsDNA viruses: the entomopoxviruses (EPVs, Poxviridae and the baculoviruses (BVs. EPVs and BVs have overlapping ecological niches and have independently evolved similar infection processes. They are, in theory, subjected to the same selective pressures from their host’s immune responses. Their accessory genomes might, therefore, bear analogous genomic signatures of convergent adaption and could point out key genomic mechanisms of adaptation hitherto undetected in viruses. We uncovered 32 homologous, yet independent acquisitions of genes originating from insect hosts, different eukaryotes, bacteria and viruses. We showed different evolutionary levels of gene acquisition convergence in these viruses, underlining a continuous evolutionary process. We found both recent and ancient gene acquisitions possibly involved to the adaptation to both specific and distantly related hosts. Multidirectional and multipartite gene exchange networks appear to constantly drive exogenous gene assimilations, bringing key adaptive innovations and shaping the life histories of large DNA viruses. This evolutionary process might lead to genome level adaptive convergence.
Log-binomial models: exploring failed convergence.
Williamson, Tyler; Eliasziw, Misha; Fick, Gordon Hilton
2013-12-13
Relative risk is a summary metric that is commonly used in epidemiological investigations. Increasingly, epidemiologists are using log-binomial models to study the impact of a set of predictor variables on a single binary outcome, as they naturally offer relative risks. However, standard statistical software may report failed convergence when attempting to fit log-binomial models in certain settings. The methods that have been proposed in the literature for dealing with failed convergence use approximate solutions to avoid the issue. This research looks directly at the log-likelihood function for the simplest log-binomial model where failed convergence has been observed, a model with a single linear predictor with three levels. The possible causes of failed convergence are explored and potential solutions are presented for some cases. Among the principal causes is a failure of the fitting algorithm to converge despite the log-likelihood function having a single finite maximum. Despite these limitations, log-binomial models are a viable option for epidemiologists wishing to describe the relationship between a set of predictors and a binary outcome where relative risk is the desired summary measure. Epidemiologists are encouraged to continue to use log-binomial models and advocate for improvements to the fitting algorithms to promote the widespread use of log-binomial models.
Noise can speed convergence in Markov chains.
Franzke, Brandon; Kosko, Bart
2011-10-01
A new theorem shows that noise can speed convergence to equilibrium in discrete finite-state Markov chains. The noise applies to the state density and helps the Markov chain explore improbable regions of the state space. The theorem ensures that a stochastic-resonance noise benefit exists for states that obey a vector-norm inequality. Such noise leads to faster convergence because the noise reduces the norm components. A corollary shows that a noise benefit still occurs if the system states obey an alternate norm inequality. This leads to a noise-benefit algorithm that requires knowledge of the steady state. An alternative blind algorithm uses only past state information to achieve a weaker noise benefit. Simulations illustrate the predicted noise benefits in three well-known Markov models. The first model is a two-parameter Ehrenfest diffusion model that shows how noise benefits can occur in the class of birth-death processes. The second model is a Wright-Fisher model of genotype drift in population genetics. The third model is a chemical reaction network of zeolite crystallization. A fourth simulation shows a convergence rate increase of 64% for states that satisfy the theorem and an increase of 53% for states that satisfy the corollary. A final simulation shows that even suboptimal noise can speed convergence if the noise applies over successive time cycles. Noise benefits tend to be sharpest in Markov models that do not converge quickly and that do not have strong absorbing states.
Sectoral Energy, and Labour, Productivity Convergence
International Nuclear Information System (INIS)
Mulder, P.; De Groot, H.L.F.
2007-01-01
This paper empirically investigates the development of cross-country differences in energy- and labour productivity. The analysis is performed at a detailed sectoral level for 14 OECD countries, covering the period 1970-1997. A ρ-convergence analysis reveals that the development over time of the cross-country variation in productivity performance differs across sectors as well as across different levels of aggregation. Both patterns of convergence as well as divergence are found. Cross-country variation of productivity levels is typically larger for energy than for labour. A β-convergence analysis provides support for the hypothesis that in most sectors lagging countries tend to catch up with technological leaders, in particular in terms of energy productivity. Moreover, the results show that convergence is conditional, meaning that productivity levels converge to country-specific steady states. Energy prices and wages are shown to positively affect energy- and labour-productivity growth, respectively. We also find evidence for the importance of economies of scale, whereas the investment share, openness and specialization play only a modest role in explaining cross-country variation in energy- and labour-productivity growth
Multiple pathways of commodity crop expansion in tropical forest landscapes
Meyfroidt, Patrick; Carlson, Kimberly M.; Fagan, Matthew E.; Gutiérrez-Vélez, Victor H.; Macedo, Marcia N.; Curran, Lisa M.; DeFries, Ruth S.; Dyer, George A.; Gibbs, Holly K.; Lambin, Eric F.; Morton, Douglas C.; Robiglio, Valentina
2014-07-01
Commodity crop expansion, for both global and domestic urban markets, follows multiple land change pathways entailing direct and indirect deforestation, and results in various social and environmental impacts. Here we compare six published case studies of rapid commodity crop expansion within forested tropical regions. Across cases, between 1.7% and 89.5% of new commodity cropland was sourced from forestlands. Four main factors controlled pathways of commodity crop expansion: (i) the availability of suitable forestland, which is determined by forest area, agroecological or accessibility constraints, and land use policies, (ii) economic and technical characteristics of agricultural systems, (iii) differences in constraints and strategies between small-scale and large-scale actors, and (iv) variable costs and benefits of forest clearing. When remaining forests were unsuitable for agriculture and/or policies restricted forest encroachment, a larger share of commodity crop expansion occurred by conversion of existing agricultural lands, and land use displacement was smaller. Expansion strategies of large-scale actors emerge from context-specific balances between the search for suitable lands; transaction costs or conflicts associated with expanding into forests or other state-owned lands versus smallholder lands; net benefits of forest clearing; and greater access to infrastructure in already-cleared lands. We propose five hypotheses to be tested in further studies: (i) land availability mediates expansion pathways and the likelihood that land use is displaced to distant, rather than to local places; (ii) use of already-cleared lands is favored when commodity crops require access to infrastructure; (iii) in proportion to total agricultural expansion, large-scale actors generate more clearing of mature forests than smallholders; (iv) property rights and land tenure security influence the actors participating in commodity crop expansion, the form of land use displacement
Multiple pathways of commodity crop expansion in tropical forest landscapes
International Nuclear Information System (INIS)
Meyfroidt, Patrick; Lambin, Eric F; Carlson, Kimberly M; Fagan, Matthew E; DeFries, Ruth S; Gutiérrez-Vélez, Victor H; Macedo, Marcia N; Curran, Lisa M; Dyer, George A; Gibbs, Holly K; Morton, Douglas C; Robiglio, Valentina
2014-01-01
Commodity crop expansion, for both global and domestic urban markets, follows multiple land change pathways entailing direct and indirect deforestation, and results in various social and environmental impacts. Here we compare six published case studies of rapid commodity crop expansion within forested tropical regions. Across cases, between 1.7% and 89.5% of new commodity cropland was sourced from forestlands. Four main factors controlled pathways of commodity crop expansion: (i) the availability of suitable forestland, which is determined by forest area, agroecological or accessibility constraints, and land use policies, (ii) economic and technical characteristics of agricultural systems, (iii) differences in constraints and strategies between small-scale and large-scale actors, and (iv) variable costs and benefits of forest clearing. When remaining forests were unsuitable for agriculture and/or policies restricted forest encroachment, a larger share of commodity crop expansion occurred by conversion of existing agricultural lands, and land use displacement was smaller. Expansion strategies of large-scale actors emerge from context-specific balances between the search for suitable lands; transaction costs or conflicts associated with expanding into forests or other state-owned lands versus smallholder lands; net benefits of forest clearing; and greater access to infrastructure in already-cleared lands. We propose five hypotheses to be tested in further studies: (i) land availability mediates expansion pathways and the likelihood that land use is displaced to distant, rather than to local places; (ii) use of already-cleared lands is favored when commodity crops require access to infrastructure; (iii) in proportion to total agricultural expansion, large-scale actors generate more clearing of mature forests than smallholders; (iv) property rights and land tenure security influence the actors participating in commodity crop expansion, the form of land use displacement
Evaluating expansion strategies for startup European Union dairy farm businesses.
McDonald, R; Shalloo, L; Pierce, K M; Horan, B
2013-06-01
A stochastic whole-farm simulation model was used to examine alternative strategies for new entrant dairy farmers to grow and develop dairy farm businesses in the context of European Union (EU) milk quota abolition in 2015. Six alternative strategies were compared: remain static, natural growth expansion, waiting until after EU milk quota abolition to expand, a full-scale expansion strategy without milk quotas and not incurring super levy penalties, a full-scale expansion strategy with milk quotas and incurring super levy penalties, and once-a-day milking until EU milk quota abolition, followed by full-scale expansion. Each discrete whole farm investment strategy was evaluated over a 15-yr period (2013-2027) using multiple financial stability and risk indicators, including overall discounted farm business profitability, net worth change, return on investment, and financial risk. The results of this study indicate that, although associated with increased risk, dairy farm expansion will ensure the future profitability of the farm business. Within the context of EU milk quotas until 2015, the most attractive expansion strategy is to increase cow numbers while avoiding super levy fines using once-a-day milking techniques, increasing to the full capacity of the dairy farm once milk quotas are removed. In contrast, the results also indicate that dairy farms that remain static will experience a significant reduction in farm profitability in the coming year due to production cost inflation. Cash flow deficits were observed during the initial year of expansion and, therefore, rapidly expanding dairy farm businesses require a significant cash reserve to alleviate business risk during the initial year of expansion. The results of this analysis also indicate that dairy farm businesses that expand using lower cost capital investments and avoid milk quota super levy fines significantly reduce the financial risks associated with expansion. Copyright © 2013 American Dairy Science
Plasma expansion: fundamentals and applications
International Nuclear Information System (INIS)
Engeln, R; Mazouffre, S; Vankan, P; Bakker, I; Schram, D C
2002-01-01
The study of plasma expansion is interesting from a fundamental point of view as well as from a more applied point of view. We here give a short overview of the way properties like density, velocity and temperature behave in an expanding thermal plasma. Experimental data show that the basic phenomena of plasma expansion are to some extent similar to those of the expansion of a hot neutral gas. From the application point of view, we present first results on the use of an expanding thermal plasma in the plasma-activated catalysis of ammonia, from N 2 -H 2 mixtures
Convergent dynamics for multistable delayed neural networks
International Nuclear Information System (INIS)
Shih, Chih-Wen; Tseng, Jui-Pin
2008-01-01
This investigation aims at developing a methodology to establish convergence of dynamics for delayed neural network systems with multiple stable equilibria. The present approach is general and can be applied to several network models. We take the Hopfield-type neural networks with both instantaneous and delayed feedbacks to illustrate the idea. We shall construct the complete dynamical scenario which comprises exactly 2 n stable equilibria and exactly (3 n − 2 n ) unstable equilibria for the n-neuron network. In addition, it is shown that every solution of the system converges to one of the equilibria as time tends to infinity. The approach is based on employing the geometrical structure of the network system. Positively invariant sets and componentwise dynamical properties are derived under the geometrical configuration. An iteration scheme is subsequently designed to confirm the convergence of dynamics for the system. Two examples with numerical simulations are arranged to illustrate the present theory
Well-Tempered Metadynamics Converges Asymptotically
Dama, James F.; Parrinello, Michele; Voth, Gregory A.
2014-06-01
Metadynamics is a versatile and capable enhanced sampling method for the computational study of soft matter materials and biomolecular systems. However, over a decade of application and several attempts to give this adaptive umbrella sampling method a firm theoretical grounding prove that a rigorous convergence analysis is elusive. This Letter describes such an analysis, demonstrating that well-tempered metadynamics converges to the final state it was designed to reach and, therefore, that the simple formulas currently used to interpret the final converged state of tempered metadynamics are correct and exact. The results do not rely on any assumption that the collective variable dynamics are effectively Brownian or any idealizations of the hill deposition function; instead, they suggest new, more permissive criteria for the method to be well behaved. The results apply to tempered metadynamics with or without adaptive Gaussians or boundary corrections and whether the bias is stored approximately on a grid or exactly.
Filamentation of a converging heavy ion beam
International Nuclear Information System (INIS)
Lee, E.P.; Buchanan, H.L.; Rosenbluth, M.N.
1980-01-01
A major concern in the use of heavy ion beams as igniters in pellet fusion systems is the vulnerability of the beam to the transverse flamentation instability. The undesirable consequence of this mode is the transverse heating of the beam to the extent that convergence on the pellet becomes impossible. This work considers the case of a beam injected into a gas filled reactor vessel, where finite pulse length and propagation distance play an important role in limiting growth. Two geometries are analyzed: a nonconverging case where the radius at injection is nearly equal to the desired radius at the pellet, and a converging case in which the injection radius is large and the beam is pre-focused to converge at the target. It is found that a cold beam will be severely disrupted if the product of the magnetic plasma frequency and the propagation distance is much larger than unity
Multicloud: Multigrid convergence with a meshless operator
International Nuclear Information System (INIS)
Katz, Aaron; Jameson, Antony
2009-01-01
The primary objective of this work is to develop and test a new convergence acceleration technique we call multicloud. Multicloud is well-founded in the mathematical basis of multigrid, but relies on a meshless operator on coarse levels. The meshless operator enables extremely simple and automatic coarsening procedures for arbitrary meshes using arbitrary fine level discretization schemes. The performance of multicloud is compared with established multigrid techniques for structured and unstructured meshes for the Euler equations on two-dimensional test cases. Results indicate comparable convergence rates per unit work for multicloud and multigrid. However, because of its mesh and scheme transparency, multicloud may be applied to a wide array of problems with no modification of fine level schemes as is often required with agglomeration techniques. The implication is that multicloud can be implemented in a completely modular fashion, allowing researchers to develop fine level algorithms independent of the convergence accelerator for complex three-dimensional problems.
Plurality or convergence in sustainability reporting standards?
Directory of Open Access Journals (Sweden)
Nadia Albu
2013-11-01
Full Text Available Over the last years an increasing number of companies issued Corporate Social Responsibility (CSR or Sustainability Reports to complement their traditional financial reporting. Companies use various sustainability reporting standards or develop their own reporting frameworks starting from the existing ones. This variation of practices pointed out by empirical research raises questions about the quality and comparability of sustainability reporting, its role in the sustainable development, and also about the suitability of accepting the plurality of reporting frameworks or the need for convergence. This study aims to investigate the issues of plurality and convergence in sustainability reporting standards, by mobilizing the discourses on regulation and the case of a group of companies in the IT industry in order to shed some light on the current challenges in this area. We frame a discussion on the opportunities and pitfalls of convergence in sustainability reporting regulations and contribute to a better understanding of this issue by academics, preparers, users and standard setters
International Accounting Convergences Related to EU Admitance
Directory of Open Access Journals (Sweden)
Niculae Feleaga
2006-05-01
Full Text Available Starting from January 1, 2005, member countries of the European Union began the obligatory or optional application of the international standards IAS/IFRS for consolidated accounts, what means a revolution in financial reporting of the enterprises. In regards to the individual accounts (generally based on the national book-keeping standards these will converge gradually to referential international book-keeper on short and medium term. At the world level the process which dominates the accounting systems is the convergence between american and international reference system, followed immediatly more or less by the convergence between national accounting systems and the international one. Where Romania and its specialists are situated confronting this process? A reflection subject which finalises this article.
Science and technology convergence: with emphasis for nanotechnology-inspired convergence
International Nuclear Information System (INIS)
Bainbridge, William S.; Roco, Mihail C.
2016-01-01
Convergence offers a new universe of discovery, innovation, and application opportunities through specific theories, principles, and methods to be implemented in research, education, production, and other societal activities. Using a holistic approach with shared goals, convergence seeks to transcend existing human limitations to achieve improved conditions for work, learning, aging, physical, and cognitive wellness. This paper outlines ten key theories that offer complementary perspectives on this complex dynamic. Principles and methods are proposed to facilitate and enhance science and technology convergence. Several convergence success stories in the first part of the 21st century—including nanotechnology and other emerging technologies—are discussed in parallel with case studies focused on the future. The formulation of relevant theories, principles, and methods aims at establishing the convergence science.
Science and technology convergence: with emphasis for nanotechnology-inspired convergence
Energy Technology Data Exchange (ETDEWEB)
Bainbridge, William S.; Roco, Mihail C., E-mail: mroco@nsf.gov [National Science Foundation (United States)
2016-07-15
Convergence offers a new universe of discovery, innovation, and application opportunities through specific theories, principles, and methods to be implemented in research, education, production, and other societal activities. Using a holistic approach with shared goals, convergence seeks to transcend existing human limitations to achieve improved conditions for work, learning, aging, physical, and cognitive wellness. This paper outlines ten key theories that offer complementary perspectives on this complex dynamic. Principles and methods are proposed to facilitate and enhance science and technology convergence. Several convergence success stories in the first part of the 21st century—including nanotechnology and other emerging technologies—are discussed in parallel with case studies focused on the future. The formulation of relevant theories, principles, and methods aims at establishing the convergence science.
Convergence of the Distorted Wave Born series
International Nuclear Information System (INIS)
MacMillan, D.S.
1981-01-01
The aim of this thesis is to begin to understand the idea of reaction mechanisms in nonrelativistic scattering systems. If we have a complete reaction theory of a particular scattering system, then we claim that the theory itself must contain information about important reaction mechanisms in the system. This information can be used to decide what reaction mechanisms should be included in an approximate calculation. To investigate this claim, we studied several solvable models. The primary concept employed in studying our models is the convergence of the multistep series generated by iterating the corresponding scattering integral equation. We known that the eigenvalues of the kernel of the Lippmann-Schwinger equation for potential scattering determine the rate of convergence of the Born series. The Born series will converge only if these eigenvalues all life within the unit circle. We extend these results to a study of the distorted wave Born series for inelastic scattering. The convergence criterion tells us when approximations are valid. We learn how the convergence of the distorted wave series depends upon energy, coupling constants, angular momentum, and angular momentum transfer. In one of our models, we look at several possible distorting potentials to see which one gives the best convergence. We have also applied our results to several actual DWBA or coupled channel calculations in the literature. In addition to the study of models of two-body scattering systems, we have considered the case of rearrangement scattering. We have discussed the formulation of (N greater than or equal to 3)-body distorted wave equations in which the interior dynamics have been redistributed by introducing compact N-body distortion potentials
Specialisation and Convergence in European Regions
Directory of Open Access Journals (Sweden)
Enrico Marelli
2007-09-01
Full Text Available The purpose of this paper was to analyze specialization and convergence of European countries and regions, within the framework of integration in the EU. This is important not only for long-term real convergence processes, but also for a proper functioning of the monetary union (in the line of research on the OCA's criteria, asymmetry of shocks and synchronization of business cycles. The position of new member states is particularly delicate, also considering the forthcoming adoption of the euro by some of them. As indicated by the EU Treaty, economic growth should be balanced with economic and social cohesion that includes a careful consideration of regional disparities. Our empirical investigation focuses on the regions of EU25, further broken up into other relevant groupings (EU15, EMU, and the new members' EU10 group, over the period from 1980 (or 1990 for EU10 to 2005. This paper considers a rather fine regional disaggregation (NUTS-2 level, counting 250 regions. The analysis of different indices of specialisation point to a prevalent increase of homogeneity of sector structures across European regions, although in some cases (especially in the industrial sector and in some services specialisation has increased. For convergence, a sigma convergence's analysis confirms a reduction of disparities, both at a country and regional level. However, a trade-off between fast national growth and internal distribution has emerged in the early stages of development, as in the case of new members. Moreover, beta convergence has also been established - regarding per capita income, employment and productivity - for almost all territorial aggregates (excluding the new members since 1999. The addition of structural variables, following a beta-conditional approach, indicates a positive role for services and a negative impact of agriculture. Finally, some preliminary results have been obtained by the innovative inclusion of specialisation indices within
GLOBAL CONVERGENCE FOR THE XOR BOOLEAN NETWORKS
Ho, Juei-Ling
2009-01-01
Shih and Ho have proved a global convergent theorem for boolean network: if a map from $\\{0,1\\}^{n}$ to itself defines a boolean network has the conditions: (1) each column of the discrete Jacobian matrix of each element of $\\{0,1\\}^{n}$ is either a unit vector or a zero vector; (2) all the boolean eigenvalues of the discrete Jacobian matrix of this map evaluated at each element of $\\{0,1\\}^{n}$ are zero, then it has a unique fixed point and this boolean network is global convergent to the fi...
Convergence of Hybrid Space Mapping Algorithms
DEFF Research Database (Denmark)
Madsen, Kaj; Søndergaard, Jacob
2004-01-01
may be poor, or the method may even fail to converge to a stationary point. We consider a convex combination of the space mapping technique with a classical optimization technique. The function to be optimized has the form \\$H \\$\\backslash\\$circ f\\$ where \\$H: \\$\\backslash\\$dR\\^m \\$\\backslash......\\$mapsto \\$\\backslash\\$dR\\$ is convex and \\$f: \\$\\backslash\\$dR\\^n \\$\\backslash\\$mapsto \\$\\backslash\\$dR\\^m\\$ is smooth. Experience indicates that the combined method maintains the initial efficiency of the space mapping technique. We prove that the global convergence property of the classical technique is also...
Lacunary ideal convergence of multiple sequences
Directory of Open Access Journals (Sweden)
Bipan Hazarika
2016-01-01
Full Text Available An ideal I is a family of subsets of N×N which is closed under taking finite unions and subsets of its elements. In this article, the concept of lacunary ideal convergence of double sequences has been introduced. Also the relation between lacunary ideal convergent and lacunary Cauchy double sequences has been established. Furthermore, the notions of lacunary ideal limit point and lacunary ideal cluster points have been introduced and find the relation between these two notions. Finally, we have studied the properties such as solidity, monotonic.
Nanotechnologies, technologies converging and potential biomedical applications
International Nuclear Information System (INIS)
Capuano, Vincenzo
2005-01-01
The applications of nanotechnology to biology and medicine appear really promising far diagnostics, for various therapeutic approaches and in medical instrumentations. The growing synergism among nanotechnology, biotechnology, information technology and cognitive sciences, their convergence (NBIC) from the nano scale, could involve on next decades great changes in medicine, from a reactive to a predictive and preventive approach. It is expected that NBIC converging technologies could achieve tremendous improvements in human abilities and enhance societal achievements. It appears therefore necessary a careful assessment of related social and ethical implications, in the framework of a constant dialogue between science and society [it
Orthogonal expansions related to compact Gelfand pairs
DEFF Research Database (Denmark)
Berg, Christian; Peron, Ana P.; Porcu, Emilio
2017-01-01
. The functions of this class are the functions having a uniformly convergent expansion ∑ϕεZB(ϕ)(u)ϕ(x) for xεG,uεL, where the sum is over the space Z of positive definite spherical functions ϕ:G→C for the Gelfand pair, and (B(ϕ))ϕεZ is a family of continuous positive definite functions on L such that ∑ϕε......For a locally compact group G, let P(G) denote the set of continuous positive definite functions f:G→C. Given a compact Gelfand pair (G,K) and a locally compact group L, we characterize the class PK#(G,L) of functions fεP(G×L) which are bi-invariant in the G-variable with respect to K......(d)) and (U(q),U(q-1)) as well as for the product of these Gelfand pairs.The result generalizes recent theorems of Berg-Porcu (2016) and Guella-Menegatto (2016)....
Warp drive with zero expansion
Energy Technology Data Exchange (ETDEWEB)
Natario, Jose [Department of Mathematics, Instituto Superior Tecnico (Portugal)
2002-03-21
It is commonly believed that Alcubierre's warp drive works by contracting space in front of the warp bubble and expanding the space behind it. We show that this contraction/expansion is but a marginal consequence of the choice made by Alcubierre and explicitly construct a similar spacetime where no contraction/expansion occurs. Global and optical properties of warp-drive spacetimes are also discussed.
International Nuclear Information System (INIS)
Andro, Jean.
1973-01-01
The invention relates the expansion lyre-shaped tube portions formed in dudgeoned tubular bundles between two bottom plates. An expansion lyre comprises at least two sets of tubes of unequal lengths coplanar and symmetrical with respect to the main tube axis, with connecting portions between the tubes forming said sets. The invention applies to apparatus such as heat exchangers, heaters, superheaters or breeders [fr
Estimates of expansion time scales
International Nuclear Information System (INIS)
Jones, E.M.
1979-01-01
Monte Carlo simulations of the expansion of a spacefaring civilization show that descendants of that civilization should be found near virtually every useful star in the Galaxy in a time much less than the current age of the Galaxy. Only extreme assumptions about local population growth rates, emigration rates, or ship ranges can slow or halt an expansion. The apparent absence of extraterrestrials from the solar system suggests that no such civilization has arisen in the Galaxy. 1 figure
Strategic Complexity and Global Expansion
DEFF Research Database (Denmark)
Oladottir, Asta Dis; Hobdari, Bersant; Papanastassiou, Marina
2012-01-01
The purpose of this paper is to analyse the determinants of global expansion strategies of newcomer Multinational Corporations (MNCs) by focusing on Iceland, Israel and Ireland. We argue that newcomer MNCs from small open economies pursue complex global expansion strategies (CGES). We distinguish....... The empirical evidence suggests that newcomer MNCs move away from simplistic dualities in the formulation of their strategic choices towards more complex options as a means of maintaining and enhancing their global competitiveness....
Range expansion of heterogeneous populations.
Reiter, Matthias; Rulands, Steffen; Frey, Erwin
2014-04-11
Risk spreading in bacterial populations is generally regarded as a strategy to maximize survival. Here, we study its role during range expansion of a genetically diverse population where growth and motility are two alternative traits. We find that during the initial expansion phase fast-growing cells do have a selective advantage. By contrast, asymptotically, generalists balancing motility and reproduction are evolutionarily most successful. These findings are rationalized by a set of coupled Fisher equations complemented by stochastic simulations.
Zipf rank approach and cross-country convergence of incomes
Shao, Jia; Ivanov, Plamen Ch.; Urošević, Branko; Stanley, H. Eugene; Podobnik, Boris
2011-05-01
We employ a concept popular in physics —the Zipf rank approach— in order to estimate the number of years that EU members would need in order to achieve "convergence" of their per capita incomes. Assuming that trends in the past twenty years continue to hold in the future, we find that after t≈30 years both developing and developed EU countries indexed by i will have comparable values of their per capita gross domestic product {\\cal G}_{i,t} . Besides the traditional Zipf rank approach we also propose a weighted Zipf rank method. In contrast to the EU block, on the world level the Zipf rank approach shows that, between 1960 and 2009, cross-country income differences increased over time. For a brief period during the 2007-2008 global economic crisis, at world level the {\\cal G}_{i,t} of richer countries declined more rapidly than the {\\cal G}_{i,t} of poorer countries, in contrast to EU where the {\\cal G}_{i,t} of developing EU countries declined faster than the {\\cal G}_{i,t} of developed EU countries, indicating that the recession interrupted the convergence between EU members. We propose a simple model of GDP evolution that accounts for the scaling we observe in the data.
Haines, Brian M.; Yi, S. A.; Olson, R. E.; Khan, S. F.; Kyrala, G. A.; Zylstra, A. B.; Bradley, P. A.; Peterson, R. R.; Kline, J. L.; Leeper, R. J.; Shah, R. C.
2017-07-01
The wetted foam capsule design for inertial confinement fusion capsules, which includes a foam layer wetted with deuterium-tritium liquid, enables layered capsule implosions with a wide range of hot-spot convergence ratios (CR) on the National Ignition Facility. We present a full-scale wetted foam capsule design that demonstrates high gain in one-dimensional simulations. In these simulations, increasing the convergence ratio leads to an improved capsule yield due to higher hot-spot temperatures and increased fuel areal density. High-resolution two-dimensional simulations of this design are presented with detailed and well resolved models for the capsule fill tube, support tent, surface roughness, and predicted asymmetries in the x-ray drive. Our modeling of these asymmetries is validated by comparisons with available experimental data. In 2D simulations of the full-scale wetted foam capsule design, jetting caused by the fill tube is prevented by the expansion of the tungsten-doped shell layer due to preheat. While the impacts of surface roughness and predicted asymmetries in the x-ray drive are enhanced by convergence effects, likely underpredicted in 2D at high CR, simulations predict that the capsule is robust to these features. Nevertheless, the design is highly susceptible to the effects of the capsule support tent, which negates all of the one-dimensional benefits of increasing the convergence ratio. Indeed, when the support tent is included in simulations, the yield decreases as the convergence ratio is increased for CR > 20. Nevertheless, the results suggest that the full-scale wetted foam design has the potential to outperform ice layer capsules given currently achievable levels of asymmetries when fielded at low convergence ratios (CR < 20).
Professional Communication and Translation in Convergence
DEFF Research Database (Denmark)
Gnecci, Marusca; Maylath, Bruce; Mousten, Birthe
2008-01-01
As translation of technical documents becomes commonplace, and as translation becomes more automated, the roles of translator and technical communicator appear to be converging. This paper examines the trend revealed from recent surveys, and it suggests further research to determine if the trend...... is likely to continue. The paper also provides recommendations for academic programs interested in adjusting to the trend....
Strong Ideal Convergence in Probabilistic Metric Spaces
Indian Academy of Sciences (India)
In the present paper we introduce the concepts of strongly ideal convergent sequence and strong ideal Cauchy sequence in a probabilistic metric (PM) space endowed with the strong topology, and establish some basic facts. Next, we define the strong ideal limit points and the strong ideal cluster points of a sequence in this ...
Convergent acquisition of antibiotic resistance determinants ...
African Journals Online (AJOL)
Convergent acquisition of antibiotic resistance determinants amongst the Enterobacteriaceae isolates of the Mhlathuze River, KwaZulu-Natal (RSA) ... The possibility of transmission of resistant genes between bacteria (especially pathogenic) which invade human and animal populations within this river poses a health risk ...
Culture and Social Psychology: Converging Perspectives
Dimaggio, Paul; Markus, Hazel Rose
2010-01-01
Views of culture in psychology and sociology have converged markedly in the past two decades. Both have rejected what Adams and Markus (2004) refer to as the "entity" conception of culture--the view that culture is coherent, stable, and located in the heads of collectivities' members--in favor of more supple and dynamic constructs. Culture, in…
Evolutionary convergence and biologically embodied cognition
Keijzer, Franciscus
2017-01-01
The study of evolutionary patterns of cognitive convergence would be greatly helped by a clear demarcation of cognition. Cognition is often used as an equivalent of mind, making it difficult to pin down empirically or to apply it confidently beyond the human condition. Recent developments in
Convergence properties of the effective interaction
International Nuclear Information System (INIS)
Ellis, P.J.; Engeland, T.; Hjorth-Jensen, M.; Holt, A.; Osnes, E.
1994-01-01
The convergence properties of two perturbative schemes to sum the so-called folded diagrams are critically reviewed in this work, with an emphasis on the intruder state problem. The methods we study are the approaches of Kuo and co-workers and Lee and Suzuki. The suitability of the two schemes for shell-model calculations is discussed. ((orig.))
RNA polymerase II collision interrupts convergent transcription
DEFF Research Database (Denmark)
Hobson, David J; Wei, Wu; Steinmetz, Lars M
2012-01-01
Antisense noncoding transcripts, genes-within-genes, and convergent gene pairs are prevalent among eukaryotes. The existence of such transcription units raises the question of what happens when RNA polymerase II (RNAPII) molecules collide head-to-head. Here we use a combination of biochemical...
Professional Communication and Translation in Convergence
DEFF Research Database (Denmark)
Gnecci, Marusca; Maylath, Bruce; Mousten, Birthe
2008-01-01
As translation of technical documents becomes commonplace, and as translation becomes more automated, the roles of translator and technical communicator appear to be converging. This paper examines the trend revealed from recent surveys, and it suggests further research to determine if the trend...
Strong Statistical Convergence in Probabilistic Metric Spaces
Şençimen, Celaleddin; Pehlivan, Serpil
2008-01-01
In this article, we introduce the concepts of strongly statistically convergent sequence and strong statistically Cauchy sequence in a probabilistic metric (PM) space endowed with the strong topology, and establish some basic facts. Next, we define the strong statistical limit points and the strong statistical cluster points of a sequence in this space and investigate the relations between these concepts.
Convergence properties of the effective interaction
International Nuclear Information System (INIS)
Ellis, P.J.; Engeland, T.; Hjorth-Jensen, M.; Holt, A.; Osnes, E.
1993-10-01
The convergence properties of two perturbative schemes to sum the so called folded diagrams are critically reviewed with an emphasis on the intruder state problem. The methods studied are the approaches of Kuo and co-workers and Lee and Suzuki. The suitability of the two schemes for shell-model calculations is discussed. 11 refs., 3 figs., 1 tab
Another Perspective: A Response to "Toward Convergence"
Regelski, Thomas A.
2013-01-01
This response by Thomas A. Regelski was solicited to complement the lead article in this issue, "Toward Convergence: Adapting Music Education to Contemporary Society and Participatory Culture" by Evan S. Tobias. The author notes that many interesting and vital questions and alternatives that are often studiously ignored, overlooked, or taken for…
Convergence Science in a Nano World
Cady, Nathaniel
2013-01-01
Convergence is a new paradigm that brings together critical advances in the life sciences, physical sciences and engineering. Going beyond traditional “interdisciplinary” studies, “convergence” describes the culmination of truly integrated research and development, yielding revolutionary advances in both scientific research and new technologies. At its core, nanotechnology embodies these elements of convergence science by bringing together multiple disciplines with the goal of creating innovative and groundbreaking technologies. In the biological and biomedical sciences, nanotechnology research has resulted in dramatic improvements in sensors, diagnostics, imaging, and even therapeutics. In particular, there is a current push to examine the interface between the biological world and micro/nano-scale systems. For example, my laboratory is developing novel strategies for spatial patterning of biomolecules, electrical and optical biosensing, nanomaterial delivery systems, cellular patterning techniques, and the study of cellular interactions with nano-structured surfaces. In this seminar, I will give examples of how convergent research is being applied to three major areas of biological research &endash; cancer diagnostics, microbiology, and DNA-based biosensing. These topics will be presented as case studies, showing the benefits (and challenges) of multi-disciplinary, convergent research and development.
Summability of alterations of convergent series
Directory of Open Access Journals (Sweden)
T. A. Keagy
1981-01-01
Full Text Available The effect of splitting, rearrangement, and grouping series alterations on the summability of a convergent series by ℓ−ℓ and cs−cs matrix methods is studied. Conditions are determined that guarantee the existence of alterations that are transformed into divergent series and into series with preassigned sums.
International convergence of capital market interest rates.
Fase, M.M.G.; Vlaar, P.J.G.
1997-01-01
This article investigates the extent of capital market interest rate convergence among six EU countries on the one hand, and a group of four countries with floating exchange rates - US, Germany, Japan and Switzerland - on the other. We conclude that interest rate changes within the EU have been and
World health inequality: convergence, divergence, and development.
Clark, Rob
2011-02-01
Recent studies characterize the last half of the twentieth century as an era of cross-national health convergence, with some attributing welfare gains in the developing world to economic growth. In this study, I examine the extent to which welfare outcomes have actually converged and the extent to which economic development is responsible for the observed trends. Drawing from estimates covering 195 nations during the 1955-2005 period, I find that life expectancy averages converged during this time, but that infant mortality rates continuously diverged. I develop a narrative that implicates economic development in these contrasting trends, suggesting that health outcomes follow a "welfare Kuznets curve." Among poor countries, economic development improves life expectancy more than it reduces infant mortality, whereas the situation is reversed among wealthier nations. In this way, development has contributed to both convergence in life expectancy and divergence in infant mortality. Drawing from 674 observations across 163 countries during the 1980-2005 period, I find that the positive effect of GDP PC on life expectancy attenuates at higher levels of development, while the negative effect of GDP PC on infant mortality grows stronger. Copyright © 2010 Elsevier Ltd. All rights reserved.
Intermediates and Generic Convergence to Equilibria
DEFF Research Database (Denmark)
Marcondes de Freitas, Michael; Wiuf, Carsten; Feliu, Elisenda
2017-01-01
Known graphical conditions for the generic and global convergence to equilibria of the dynamical system arising from a reaction network are shown to be invariant under the so-called successive removal of intermediates, a systematic procedure to simplify the network, making the graphical conditions...
On Investigating GMRES Convergence using Unitary Matrices
Czech Academy of Sciences Publication Activity Database
Duintjer Tebbens, Jurjen; Meurant, G.; Sadok, H.; Strakoš, Z.
2014-01-01
Roč. 450, 1 June (2014), s. 83-107 ISSN 0024-3795 Grant - others:GA AV ČR(CZ) M100301201; GA MŠk(CZ) LL1202 Institutional support: RVO:67985807 Keywords : GMRES convergence * unitary matrices * unitary spectra * normal matrices * Krylov residual subspace * Schur parameters Subject RIV: BA - General Mathematics Impact factor: 0.939, year: 2014
Exponential rate of convergence in current reservoirs
De Masi, Anna; Presutti, Errico; Tsagkarogiannis, Dimitrios; Vares, Maria Eulalia
2015-01-01
In this paper, we consider a family of interacting particle systems on $[-N,N]$ that arises as a natural model for current reservoirs and Fick's law. We study the exponential rate of convergence to the stationary measure, which we prove to be of the order $N^{-2}$.
Uniform Statistical Convergence on Time Scales
Directory of Open Access Journals (Sweden)
Yavuz Altin
2014-01-01
Full Text Available We will introduce the concept of m- and (λ,m-uniform density of a set and m- and (λ,m-uniform statistical convergence on an arbitrary time scale. However, we will define m-uniform Cauchy function on a time scale. Furthermore, some relations about these new notions are also obtained.
Impact of fixed-mobile convergence
DEFF Research Database (Denmark)
Pachnicke, Stephan; Andrus, Bogdan-Mihai; Autenrieth, Achim
2016-01-01
Fixed-Mobile Convergence (FMC) is a very trendy concept as it promises integration of the previously separated fixed access network and the mobile network. From this novel approach telecommunication operators expect significant cost savings and performance improvements. FMC can be separated...
Converging technologies: shaping the future of medicine
Directory of Open Access Journals (Sweden)
Iraj nabipour
2015-01-01
Full Text Available The miniaturization and virtualization processes drive converging technologies from interactions between the NBIC (Nano, Bio, Info, and Cogno technologies. The converging technologies stimulate innovation, promote research and development in different fields and produce revolutionary progresses in medicine. These technologies enable us to create contacts between brains and machines, the growth in molecular nanotechnology, the construction of respirocytes, chromallocytes, clottocytes, nanorobotic phagocytes, and nanobots. Nanobots would enter the nucleus of a cell and extract all of the genetic material and replace it with a synthetically produced copy of the original that has been manufactured in a laboratory to contain only non-defective base-pairs. It is predicted that “the regenerative medicine”, as a megatrend, will have an enormous effect on medical technologies and clinical sciences. Regenerative medicine is an application field of converging technologies in translational medicine. It attempts to translate the results of tissue engineering to construct 3D tissues and organs. Regenerative medicine is also an exciting field for induced pluripotent stem cell (iPSC and promises to bring about a paradigm shift to health care. Accumulating evidence indicates that converging technologies will offer great potentials for regenerative medicine to create innovative treatments for diseases that the traditional therapies have not been effective yet.
Directory of Open Access Journals (Sweden)
Ioana Sorina Mihuț
2013-07-01
Full Text Available Abstract: Convergence may be considered a central issue of the current economic literature, and not only, concentrating upon income distribution within different economies, but also focusing on different aspects of polarity and inequality that characterize especially the emerging economies. Testing convergence within economies may serve as a useful instrument for the validation of the economic growth models. While convergence was considered a defining element of the neoclassical growth models, the majority of the new endogenous growth models argue in favour of divergence across different economies. Testing convergence among European Union is even more challenging due to the high degree of heterogeneity that characterizes these economies. The recent accessions with ten new countries in 2004 and with another two in 2007 were considered only the first step towards assuring a sustainable convergence and finally adopting a common currency-the euro. A series of empirical studies concentrated upon testing convergence among EU, using as benchmark the real convergence quantified by the level of GDP/capita as an indicator for the living standards of every economy. The most popular approach rely on Beta and Sigma convergence, the first one being and indicator of the GDP/capita dispersion between different economies, and the later one being an estimator of the reverse relationship between GDP/capita and its initial level. The main purpose of this paper is to test Beta converge among the new EU member states, in order to obtained more information about the fact whether the poor countries are trying to catch-up with the more developed one. Also Beta convergence indicator embodies useful information about conditional and un-conditional convergence, two leading hypothesis within the neoclassical and endogenous growth models. For Beta convergence hypothesis to be valid it should be taken into consideration a ”catch-up” mechanism over a longer period of time
Role of strangeness and isospin in low density expansions of hadronic matter
de Oliveira, Thamirys; Menezes, Débora P.; Pinto, Marcus B.; Gulminelli, Francesca
2018-05-01
We compare relativistic mean-field models with their low density expansion counterparts used to mimic nonrelativistic models by consistently expanding the baryonic scalar density in powers of the baryonic number density up to O (13 /3 ) , which goes two orders beyond the order considered in previous works. We show that, due to the nontrivial density dependence of the Dirac mass, the convergence of the expansion is very slow, and the validity of the nonrelativistic approximation is questionable even at subsaturation densities. In order to analyze the roles played by strangeness and isospin we consider n -Λ and n -p matter separately. Our results indicate that these degrees of freedom play quite different roles in the expansion mechanism and n -Λ matter can be better described by low density expansions than n -p matter in general.
Implication of charm and strangeness for the convergence of the ''1/N dual unitarization'' scheme
International Nuclear Information System (INIS)
Bishari, M.
1978-01-01
Due to the substantial SU 4 -symmetry breaking, the convergence of the ''1/N topological expansion'' is considerably improved in processes involving charmed quarks. An appropriate effective quark flavour number Nsub(i) is defined for each type of quark i=u,s,c, and a simple model suggests that Nsub(u) approximately equal to 2.8, Nsub(s) approximately equal to 4.7 and Nsub(c) approximately equal to 14, thus exhibiting the improved convergence, especially in the charm sector. One also obtains σsub(el)/σsub(T) approximately equal to 1/N 2 with N 2 being replaced by the corresponding Nsub(i)'s, depending on the constituents of the colliding particles. (author)
INNOVATION VERSUS INCOME CONVERGENCE IN CENTRAL AND EASTERN EUROPE. IS THERE A CORRELATION?
Directory of Open Access Journals (Sweden)
Pop Silaghi Monica
2011-07-01
Full Text Available The heterogeneity of response of the different economies facing the world economic crisis has brought into attention once again the issue of convergence inside the European Union. The high growth rates experienced by CEEC during the last decade created an optimistic view of rapid convergence towards Western Europe. But the crisis showed that the sources of economic growth in the region were not appropriate for a long run growth. Innovation is a key source of competitiveness and a contributor to a sustainable growth path. Even though CEEC lag behind other European countries in terms of R'D investment, a certain progress can be observed. The objective of the present paper is to establish if there is a correlation between the convergence in terms of GDP and the convergence in terms of innovation for the CEEC. Based on yearly Eurostat data for the period 1998-2008, we quantify the progress of each of the 10 CEEC both in closing the income gap and the innovation gap. We then rank the countries according to their speed of convergence and perform a Spearman rank correlation analysis. The results show that, on average, convergence in R'D is not correlated with convergence in GDP. The Czech Republic is the only country with a positive correlation between R'D intensity and GDP growth. Bulgaria, Hungary and Slovakia show a negative relationship between investment in R'D and economic growth. This implies that for most of the countries in Central and Eastern Europe, economic growth during the period 1998-2008 was mostly driven by non-innovation factors.
Directory of Open Access Journals (Sweden)
Maíra Massuia de Souza
2009-10-01
transverse dimensions of maxillary dental arches by analysis of the dental casts of 15 patients with complete unilateral cleft lip and palate who presented sagittal and transverse maxillary constriction and were submitted to two distinct protocols of rapid maxillary expansion. METHODS: Seven patients were submitted to rapid maxillary expansion (RME by the conventional activation protocol (Group 1, and the others were treated by the protocol proposed by Liou and Tsai in 2005, with alternated expansion and constriction (Group 2. Both groups were later submitted to maxillary protraction with facial mask. Dental casts were obtained at two periods: before placement of a modified Haas expander (T1 and after 24 weeks of treatment (T2. Transverse distances were measured with a digital caliper to register the distances between first upper premolars (anterior area and first upper molars (posterior area. Data were statistically analyzed by the Student's t test. RESULTS AND CONCLUSION: Both protocols were equally effective, since no differences were observed between the groups as to the transverse increasing achieved.
Is China ready for its nuclear expansion?
International Nuclear Information System (INIS)
Zhou, Yun; Rengifo, Christhian; Hinze, Jonathan; Chen, Peipei
2011-01-01
China's rapid pace of nuclear energy growth is unique, and its impact on the global nuclear market as both a customer and potential future supplier is already tremendous and will continue to expand. It is crucial to understand this energy policy development and its impact on various global areas. Unfortunately, there is relatively limited English-language information available about China's nuclear power industry and its current development. This paper aims to provide a comprehensive assessment of the Chinese nuclear energy program and policy, reviewing its past, present, likely future developments, as well as to consider potential challenges that deserve further attention. This paper will explore reasons that have caused the existing industry, describe China's nuclear bureaucracy and decision making process to understand how different stakeholders play a role in China's nuclear energy development. This study concludes that China's existing nuclear program and industry, in combination with its current stable economic and political environment, provides a sound foundation for the planned nuclear expansion. However, challenges which are crucial to the success of the nuclear expansion will need to be addressed. (author)
Data-driven uncertainty quantification using the arbitrary polynomial chaos expansion
International Nuclear Information System (INIS)
Oladyshkin, S.; Nowak, W.
2012-01-01
We discuss the arbitrary polynomial chaos (aPC), which has been subject of research in a few recent theoretical papers. Like all polynomial chaos expansion techniques, aPC approximates the dependence of simulation model output on model parameters by expansion in an orthogonal polynomial basis. The aPC generalizes chaos expansion techniques towards arbitrary distributions with arbitrary probability measures, which can be either discrete, continuous, or discretized continuous and can be specified either analytically (as probability density/cumulative distribution functions), numerically as histogram or as raw data sets. We show that the aPC at finite expansion order only demands the existence of a finite number of moments and does not require the complete knowledge or even existence of a probability density function. This avoids the necessity to assign parametric probability distributions that are not sufficiently supported by limited available data. Alternatively, it allows modellers to choose freely of technical constraints the shapes of their statistical assumptions. Our key idea is to align the complexity level and order of analysis with the reliability and detail level of statistical information on the input parameters. We provide conditions for existence and clarify the relation of the aPC to statistical moments of model parameters. We test the performance of the aPC with diverse statistical distributions and with raw data. In these exemplary test cases, we illustrate the convergence with increasing expansion order and, for the first time, with increasing reliability level of statistical input information. Our results indicate that the aPC shows an exponential convergence rate and converges faster than classical polynomial chaos expansion techniques.