Multiband Treatment Research Articles

Weak antilocalization within a genuine multiband model

Weak antilocalization signatures in magnetotransport measurements provide specific information about the spin-orbit coupling at oxide interfaces. However, for many of these two-dimensional systems, the commonly used theory for single-band electrons is not appropriate. The atomic spin-orbit coupling, jointly with inversion symmetry breaking terms, mixes states of different bands, making a multiband treatment of the Cooperon equation unavoidable. Here we consider an effective ${t}_{2g}$ multiband model that allows a decomposition into a pseudospin representation $1/2\phantom{\rule{0.16em}{0ex}}\ensuremath{\bigoplus}\phantom{\rule{0.16em}{0ex}}3/2$. For the spin-$3/2$ sector, supervening quintet and septet channels from the Cooperon $3/2\phantom{\rule{0.16em}{0ex}}\ensuremath{\bigotimes}\phantom{\rule{0.16em}{0ex}}3/2$ representations alter the quantum correction considerably. We study the impact of the spin winding number at the Fermi surface and report about a new experimentally accessible structure in the magnetoconductivity that is sensitive to the ratio of single and triple spin winding contributions.

Interest of decompression in orthodontics: Case report of a keratocyst during childhood.

Keratocysts, also known as keratocystic odontogenic tumors (KCOT), make up 7% of all odontogenic cysts and develop asymptomatically in most cases. Enucleation is the benchmark treatment. However, there are surgical alternatives. Marsupialization and decompression are necessary in some cases, mainly when the KCOT is large, thus causing an increased risk of bone fracture, or if it has engulfed important elements such as the inferior alveolar nerve or teeth, consequently causing alveolar bone growth failure. The authors describe the case of a nine-year-old child treated for a large keratocyst situated in sector 4 (lower right jaw), impacting both premolars and the canine (45, 44 and 43). Surgical decompression associated with orthodontic multiband treatment were delivered to pull, and then place the three teeth in occlusion on the dental arch. With seven years hindsight since the first surgical procedure and three years since finishing orthodontic treatment, the cooperation between orthodontists and surgeons can be considered a success, from both the functional and esthetic points of view.

Board Français d’Orthodontie

Date of birth: 21/08/1988; sex: female. 3/2004 (15 years 8 months). Class II division 1 subdivision, normodivergent, asymmetry. Bimaxillary multiband treatment with intermaxillary elastics and directional forces. 3/2006 (17 years 8 months). Hawley plate and wire lingually bonded 33 to 43. 1/2007 (18 years 6 months). Marion was aged 15 years 7 months with young adult dentition. Her main reason to consult was the lower position of 11 and 21. She presented a pleasant facial appearance with a slightly asymmetrical lower facial third (chin deviated to the left). In profile, she displayed an everted lower lip and a retruded mandible. We observed pronounced Class II relationships on the left (5 mm) and Class I relationships on the right with deviation of the mandibular incisor midline. Incisor overbite was also present. All 3rd molars were present.

Board Français d’Orthodontie

Date of birth: 21/08/1988; sex: female. 3/2004 (15 years 8 months). Class II division 1 subdivision, normodivergent, asymmetry. Bimaxillary multiband treatment with intermaxillary elastics and directional forces. 3/2006 (17 years 8 months). Hawley plate and wire lingually bonded 33 to 43. 1/2007 (18 years 6 months). Marion was aged 15 years 7 months with young adult dentition. Her main reason to consult was the lower position of 11 and 21. She presented a pleasant facial appearance with a slightly asymmetrical lower facial third (chin deviated to the left). In profile, she displayed an everted lower lip and a retruded mandible . We observed pronounced Class II relationships on the left (5 mm) and Class I relationships on the right with deviation of the mandibular incisor midline. Incisor overbite was also present. All 3rd molars were present.

Multiband treatment of quantum transport in anisotropic semiconductors: Non-equilibrium Green’s function

Using the non-equilibrium Green’s function and anti-bonding orbital model, a multiband treatment of quantum transport in an anisotropic semiconductor (Si-based) system is developed. In this study, we adopt Chiang’s boundary treatment of the open boundary system into the non-equilibrium Green’s function framework, and then an easy and powerful multiband treatment method is developed to solve the transmission coefficient of Si-based semiconductor quantum structures.

European College of Orthodontics: Commission of Affiliation and Titularisation

9/12/2000 (age of patient: 8 y 8 m). Retrusive profile with a fairly harmonious face and a normodivergent pattern. Dental Class II.1; skeletal Class 1. Andreasen Activator, then bimaxillary multiband appliance on permanent dentition. 14/5/2005 (age of patient: 13 y 1 m). Plate on the upper and thermoformed splint on lower. 9/12/2006 (age of patient: 14 y 8 m). Two possible treatment options: - activator used interceptively to correct the dental Class II; - bimaxillary multiband appliance on permanent dentition. The first option was adopted to test patient compliance, improve the occlusion and shorten multiband treatment.

European College of Orthodontics: Commission of Affiliation and Titularisation

9/12/2000 (age of patient: 8 y 8 m). Retrusive profile with a fairly harmonious face and a normodivergent pattern. Dental Class II.1; skeletal Class 1. Andreasen Activator, then bimaxillary multiband appliance on permanent dentition. 14/5/2005 (age of patient: 13 y 1 m). Plate on the upper and thermoformed splint on lower. 9/12/2006 (age of patient: 14 y 8 m). Two possible treatment options: - activator used interceptively to correct the dental Class II; - bimaxillary multiband appliance on permanent dentition. The first option was adopted to test patient compliance, improve the occlusion and shorten multiband treatment.

Croissance postérieure et pronostic d’évolution des troisièmes molaires mandibulaires

The inter-dependence of overall orthodontic treatment and the development of the third molars requires the entire dentition to be taken into consideration ab initio and for the patient to be fully informed as to the extractions involved. The anatomical conditions in which the development of the wisdom teeth can occur are studied using comparative samples, with and without third molar retention, followed up to the age of 20 years. Posterior growth observed between the beginning of multiband treatment and adulthood amounted to 11/16mm (girls/boys). The initial difference in forecasting the space between the groups with retained third molars and without was slight (5.5mm). However, this difference was maintained throughout the growth period and was sufficient to guide the final choice whether to extract these teeth or allow them to erupt.

Superconductivity: An Off-Diagonal Long Range Order

In using spinor representation for the electron field, the charge density is given by a 2 × 2 matrix in the spin space. The propagator is also a 2 × 2 matrix. The diagonal term gives the usual many electron problem, and the off-diagonal term gives the superconductive state. The SCF equation for the usual many-electron problem turns out to be the gap equation for the superconductivity problem.This treatment presents a new theory for the high temperature superconductivity by using the multi-band treatment from which the attractive electron-electron coupling is effectively derived. This coupling is electronic, but not phonon associated. The energy region for making superconductivity possible is a hundred times larger than the phonon frequency.

Retrospective Analysis of Casts to Assess Cervical Headgear Treatment in the Presence of Vertical Growth Pattern

Does molar distalization as effected by cervical headgear increase the vertical dimension of occlusion in patients with vertical growth pattern? A sample of 86 patients with neutral and vertical growth pattern in the late mixed dentition stage underwent headgear treatment. Their initial and intermediary casts were retrospectively analyzed for occlusal relationships at the maxillary first molars and degrees of overjet and overbite. The only cases included were those in which headgear treatment was carried on for at least 6 months, achieving a minimum distalization of 4 mm. The intermediary casts were fabricated after headgear treatment had been completed and prior to the initiation of multiband treatment. Patients were divided into three groups (N, V1 and V2) according to the degrees of vertical growth pattern, which were determined based on y-axis angle values. Grouped by degrees of vertical growth, the data revealed occlusal relationship changes of 6-8 mm and overjet reductions of 0.6-1.2 mm. The overbite changes were unexpectedly small (0-0.04 mm). Grouped by degrees of overbite, the data revealed that headgear treatment increased the vertical dimension of occlusion in deep-bite patients (>4 mm), while giving rise to decreases in patients with overbites of <3 mm.

Magnetotunneling of holes through single and double barriers using a multiband treatment

We investigate tunneling of holes through a single barrier which is subject to an in-plane magnetic field. Band mixing between heavy and light holes is pronounced which indicates the necessity of using a multiband approach. The problem is investigated within the $4\ifmmode\times\else\texttimes\fi{}4$ Luttinger-Kohn model for bands at ${\ensuremath{\Gamma}}_{8}$, without restriction on the Luttinger parameters. The application of a magnetic field enhances the anisotropy in the transmission coefficients ${T}_{\ensuremath{\lambda}\ensuremath{\mu}}({k}_{x},{k}_{y})$ and makes transitions possible between various channels (e.g., the two light holes). It is shown that heavy holes can precess when magnetic field is in plane, since band mixing lifts the selection rules for angular momentum. The current density is calculated for a double-barrier resonant structure and compared with a previous approximate theoretical result. This comparison clearly indicates that full wave vector dependence of the tunneling process is needed in order to obtain reliable values for the current.

Department of Reviews and Abstracts

The book honors and is dedicated to Thomas M. Graber. current editor of our own AMERICAN JOURNAL OF ORTHODONTICS AND DENTOFACIAL ORTHOPEDICS. It is edited by his son, Lee W. Graber. celebrating 40 years of his father's service to the profession as a clinician, teacher, and researcher. The first chapter was written by Robert E. Moyers who in his inimitable, logical style describes his perception of what is meant by 'good orthodontics. Thereafter, the book is divided into three sections in which essays by the various authors are listed under the following headings: (1) Current Science Related to Treatment. (2) and Technique Principles, and (3) Practice Management Concerns in Orthodontics. In the first section, the essayists endeavor to answer the many questions that are so frequently posed. In a philosophic debate, Donald Enlow underscores the futility of trying to predict structural and functional changes during growt h because of the paucity Of our understanding of biologic principles. Nakamura and Koski describe what happens to the condylar perichondrium when transplanted into a nonfunctional environment. The enigma of the precise nature and mechanisms that cause pain in hyperactive jaw muscles, and their relationships to temporomandibular joint pain are explained by Lars Christensen. Is the temporomandibular joint a load-bearing joint? William Hylander's reviews of the recent advances in the understanding of the forces acting through the temporomandibular joint are thought provoking. Can we stimulate condylar growth in human patients using functional appliances? Petrovic and Stutzmann attempt to throw new light on the quintessential problem of dentofacial orthopedics. In a separate chapter, Jim McNamara likewise discusses the possibility of stimulating the mandible to grow in human patients. Lysle Johnston, in a series of collaborative experiments with his students, explores the behavior of the condyle in animals under conditions such as condylectomy, loading, and unloading in an effort to establish the true role of the condylar cartilage, hopefully putting to rest many earlier anecdotal reports. Per Rygh provides a fresh insight into the response of the periodontium during tooth movement, and the unwanted side effects such as root resorption and loss of periodontal support--all clinically oriented considerations. Nasorespiratory problems in orthodontics are briefly reviewed by Linder-Aronson. whereas Thomas Rakosi identifies different types of Class II malocclusions and emphasizes the need to recognize the various types in treatment, particularly in the mixed dentition. In the second section of the book under the heading, Treatment Techniques and Princip!es, finite-element modeling of craniofacial growth and development is eruditely discussed in a section by Moss, Salentijn, and Skalak. Schmuth o f West Germany advocates taking advantage of removable type appliance therapy 'during the early phases of treatment and is in favor of two or even three phases of orthodontic treatment for specific orthodontic problems. The treatment of skeletal open bitesby means of molar extraction, according to Frfinkel and Frfinkel. is not a panacea unless functional factors that include the postural performance of those muscles associated with the creation o f a competent oral seal are taken into consideration. The management of similar cases by means of spring-loaded occlusal bite blocks is the treatment of choice for Woodside and Linder-Aronson. In the nextthree chapters, three superb clinicians namely, Wick Alexander, Terrell Root, and Brainerd Swain--each separately discuss at length multiband treatment techniques invaluable material for those clinicians Wishing to improve their treatment skills. Bonding techniques are described by Miura; retention in the adult dentition is covered by Bj0rn Zachrisson. The challenge of the bilateral cleft palate, temporomandibular dysfunction in children, and surgical intrusion of the maxilla for the correction of open bite malocclusions are described by Rosenstein, Thflander, and Thomas and Proffit, respectively. In the final chapter of this section, Vanarsdall highlights the need for

Multiband treatment of quantum transport in interband tunnel devices.

We describe a method for computing transmission coefficients for multiband tight-binding band-structure models. In this method, the transmission probability can be calculated simply by solving a system of linear equations representing the tight-binding form of the Schro\ifmmode\ddot\else\textasciidieresis\fi{}dinger equation over a finite region of interest, with specially formulated boundary and inhomogeneous terms to account for the effects of the incoming and outgoing plane-wave states. In addition to being efficient, and simple to implement, our method is numerically stable in treating device structures with large active regions, and therefore capable of modeling realistic band-bending effects. Using this method, we examine transport properties in InAs/GaSb/AlSb-based interband tunnel structures with a realistic band-structure model. We compare our results with calculations obtained with a two-band model, which includes only the lowest conduction band and the light-hole band. We find that while the primary interband transport mechanism arises from the coupling between the InAs conduction-band states and GaSb light-hole states, in device structures containing GaSb quantum wells, the inclusion of heavy-hole states can introduce additional transmission resonances and substantial hole-mixing effects. These effects are found to have a significant influence on the current-voltage characteristics of interband devices.

Asymptotic analysis of radiative transfer problems

The equations of radiative transfer are systematically analyzed by asymptotic methods. To lowest order, the classical equilibrium diffusion approximation is recovered. The next order analysis leads to the equilibrium diffusion differential equations and initial condition, but with a boundary condition containing a linear extrapolation distance α. This quantity is related tothe solution of a canonical halfspace problem and is computed by deriving an appropriate variational principle. For the case of no scattering, an exact Wiener-Hopf solution is available. The F N solution technique is also applied to the problem of obtaining α with good results. Higher order asymptotic radiative transfer descriptions are discussed and, while not immediately constituting practical calculational techniques, do have implications for computing the parameters in the multiband treatment of the frequency variable.