Scale Unification Research Articles

Abbreviated injury scale unification: the case for a unified injury system for global use.

The Abbreviated Injury Scale (AIS), developed by the Association for the Advancement of Automotive Medicine is the most widely used anatomic injury severity scale in the world (Association for the Advancement of Automotive Medicine. The Abbreviated Injury Scale; 1985 and 1990 revisions. Des Plaines, IL: Association for the Advancement of Automotive Medicine). However, different user groups have modified the AIS system to fit their needs, and these modifications prevent ready comparison and trending of data collected in these systems in the United States and throughout the world. The United States currently has five AIS-based severity systems and two AIS-based impairment systems in use, with additional revisions forthcoming. Other modified AIS systems are known to be in use in the United Kingdom and Japan. The data collected in these systems cannot be accurately combined or compared without re-coding or the use of complex "mapping" methodologies. Furthermore, the expanding use of data linked from multiple databases to answer complex medical, engineering, or policy issues emphasizes the need for coordination between severity and other injury systems. Linkage of state-wide motor vehicle crash data with data from hospital injury classification systems, mortality files, trauma registry, and national crash databases brings into immediate focus the lack of well defined relationships between the severity coding systems and these other widely used injury systems (Mango N, Garthe E. SAE Congress, February, 1998; Johnson, S, Walker, J. NHTSA Technical Report. DOT HS 808 338, Washington, DC: NHTSA; January, 1996). With the expanding use of linked data in state and national policy decisions, it is vital that consistent standards for injury descriptions, severities, and impairments be available for clinical, engineering, and policy users. This paper compares five anatomic severity systems and two impairment systems in terms of purpose, code structure, and use and discusses the reasons for the differences between these systems. With global "harmonization" encouraging greater sharing of international data, the paper also presents the relationship of the severity and impairment systems to US morbidity and reimbursement and worldwide mortality classification systems. To resolve compatibility issues resulting from multiple injury systems, the authors propose that a "unified" system for global use be developed, configured by inputs from major "data owners," users, and analysts. The proposed unified system has six key attributes: backward compatibility with historical data through "maps" so no data are lost; "scalability" to allow a simple level of use for developing countries, a more complex level for crash research and a detailed level for clinical hospital use, all with data compatibility; the ability to satisfy the needs of the engineering community for injury location information and aspect, and also the clinical requirement for precise injury description; inherent integration with whole body severity scores to permit easy computation; compatibility with other injury data systems such as mortality, morbidity, and reimbursement systems; and a mechanism and process to maintain and upgrade the system into the 21st century. The authors believe that a "unified" injury system is a necessary and crucial advance from the currently fragmented injury system situation. Unified data can provide a pool of consistent international data to support a variety of important research and prevention and treatment efforts and is essential to satisfy the global needs of the medical and engineering communities.

String unification at intermediate energies: phenomenological viability and implications

Motivated by the fact that the string scale can be many orders of magnitude lower than the Planck mass, we investigate the required modifications in the MSSM β-functions in order to achieve intermediate (10 10–13 GeV) scale unification, keeping the traditional logarithmic running of the gauge couplings. We present examples of string unified models with the required extra matter for such a unification while we also check whether other MSSM properties (such as radiative symmetry breaking) are still applicable.

Fermion Masses and Mixings in a String Inspired Model

In the context of Calabi-Yau string models we explore the origin of characteristic pattern of quark-lepton masses and the CKM matrix. The discrete $R$-symmetry $Z_K \times Z_2$ is introduced and the $Z_2$ is assigned to the $R$-parity. The gauge symmetry at the string scale, $SU(6) \times SU(2)_R$, is broken into the standard model gauge group at a very large intermediate energy scale. At energies below the intermediate scale down-type quarks and also leptons are mixed with unobserved heavy states, respectively. On the other hand, there are no such mixings for up-type quarks. Due to the large mixings between light states and heavy ones we can derive phenomenologically viable fermion mass hierarchies and the CKM matrix. Mass spectra for intermediate-scale matter beyond the MSSM are also determined. Within this framework proton lifetime is long enough to be consistent with experimental data. As for the string scale unification of gauge couplings, however, consistent solutions are not yet found.

Supersymmetric signatures at an eγ collider

High energy electron-photon colliders provide unique opportunities for probing physics beyond the standard model. We have studied the experimental signatures for two supersymmetric scenarios, with the lightest supersymmetric particle (LSP) being either the lightest neutralino or the gravitino. In the “neutralino LSP” scenario favored by the minimal supersymmetric standard model (MSSM), it is found that some basic parameters of the model, μ, tan β, M 1 and M 2, may be uniquely determined from the outgoing electron energy spectrum without assuming high scale unification of the masses or couplings. In the “gravitino LSP” scenario which occurs naturally in models of low energy dynamical supersymmetry breaking, it is possible to have background-free signatures if the next-to-lightest supersymmetric particle (NLSP) has a long decay length. In cases that the NLSP decays quickly, ways to distinguish among the experimental signatures of the two scenarios and of the standard model (SM) background are discussed.

Fermion masses and CP violation in a model with scale unification.

It is observed that the scale-unifying model based on supersymmetry and compositeness provides a natural reason for the family mass hierarchy m e m μ m τ , and links spontaneous CP violation to the nonvanishing mass of the electron family

A model for a unification of scales. From MPlanck to mv

It is proposed that the hierarchical scales — from M Planck to m v — have a common origin. Using M Planck and the coupling constant associated with a preonic metacolor gauge force as the only input parameters, it is shown how large ratios such as ( M P1 M I ), ( M P1 δm s ), ( M P1 m w ), ( M P1 m t ) and even ( M P1 m v )≳10 27 can arise naturally. Here M I denotes an intermediate scale ∼10 11 GeV, which is identified with the scale parameter of the metacolor force, while δm s denotes SUSY-breaking mass splittings ∼ 1 TeV. Local supersymmetry together with an inhibition in the breaking of global SUSY (index theorem) as well as compositeness of quarks, leptons and Higgs play crucial roles in this approach. Two key features of the model are the natural origins of composite vector-like families with masses of order of a few hundred GeV to 1 TeV and the consequent see-saw mechanism for the generations of quark-lepton masses and CP violation.