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ABSTRACTThere is no doubt modern genetics have greatly influenced our professional and personal lives during the last decade. Uncovering genetic causes of many medical and dental pathologies is helping to narrow the diagnosis and select a treatment plan that would provide the best outcome. Importantly, having an understanding of multifactorial etiology helps direct our attention toward prevention.We now understand much better our own health problems. In some cases, we can modify our lifestyle and diet in order to prevent “environmental factors” from triggering the mutated genes inherited from our parents. Good examples are diabetes and cardiovascular diseases. If we realize we might have inherited genes for cardiovascular problems from several ancestors who had heart attacks, we already know that these genes will make us only “susceptible” for disease. Those who exercise, watch one’s weight, diet, and carefully monitor one’s lifestyle will very likely — though possessing “susceptibility genes” — stay healthier and, maybe, will never experience any cardiovascular problems.In principle, the same applies for craniofacial anomalies, especially for nonsyndromic cleft lip and palate. One needs to understand genetic and environmental causes of nonsyndromic orofacial clefts in order to prevent them.With all this in mind, the Pacific Craniofacial Team and Cleft Prevention Program have been established at the Department of Orthodontics, University of the Pacific Arthur A. Dugoni School of Dentistry in San Francisco. A partnership with Rotaplast International, Inc., has made it possible for the faculty, orthodontic residents, and students to participate in 27 multidisciplinary cleft medical missions in underdeveloped and developing countries by donating professional and educational services, and, last but not least, by collecting valuable data and specimens to further research.A significant number of research studies, including 15 master of science theses, have been accomplished in UOP’s Craniofacial Genetics Laboratory, with contributions by faculty, undergraduate and graduate students. It has been leading to a better understanding of etiology of nonsyndromic orofacial clefts. It has been learned that genetic factors and environmental factors are ethnicity-specific and, in many places throughout the world, location-specific. Thus, a specific protocol for cleft prevention has to be worked out based on genetic and nutritional studies of each specific population group in order to be effective. This is our ultimate goal.

ABSTRACTThe age at which children should start orthodontic treatment has been debated amongst orthodontists for many decades. Orthodontists can agree on what is a quality orthodontic result, but disagree as to how and when to best obtain this result. Some orthodontists contend that starting treatment in the primary dentition is the most effective means of orthodontic care. Other orthodontists would prefer to begin in the early or late mixed dentition. Still others would rather postpone treatment until the permanent dentition at approximately age 12. This article will evaluate the pros and cons of initiating treatment at different ages.

Vertical detachment energy and adiabatic electron affinity have been calculated for small carbon clusters Cn (n = 2−20), both for linear and monocyclic structures, in the framework of DFT formalism using the hybrid B3LYP functional with a basis set 6-31G* augmented of p diffuse functions. A good reproduction of experimental electron affinities has been obtained in that way for linear chains with n = 5−20 especially for odd members of the series. Results are poorer for monocyclic structures however experimental trends are reproduced. For both structures the lowest estimated fragmentation energy corresponding to the loss of C3 remains larger than electron affinities for the sizes considered.

Energies and wave functions for the ground state and several excited electronic states are reported for Li^- and Na^- negative ions. Calculations have been achieved in the framework of a model potential method using s, p, d, and f atomic Slater-type basis orbitals. The electronic correlation has been considered through configuration interaction calculations. Present results are compared with available experimental and theoretical data.

A theoretical investigation of the electronic structure of the molecular ion LiNa⁺ (adiabatic potential energy curves, rovibrational energies, spectroscopic constants and dipole moments) has been performed in the framework of a model potential method. Such information, not yet available to the best of our knowledge except for the ground state, constitutes the input data for simulations of above threshold dissociation of LiNa⁺. Although most of the energy curves are found to be dissociative, some present potential wells located at intermediate internuclear distances. A long-range extrapolation is proposed for the lowest states.

Upon request of experimentalists now engaged in high-resolution spectroscopic investigations of the molecule KRb, we have determined the potential energy of electronic states 2S+1Λ(+)correlating up to the limit K(5p) + Rb(5s) and of electronic states Ω(+/−)correlating up to the limit K(4s) + Rb(4d2D3/2) in a large range of internuclear distance R. For the five states so far observed, the agreement between calculated and experimental molecular constants is good with ΔRe< 0.08 Å, Δωe< 6 cm−1, and ΔTe< 140 cm−1. Extensive numerical data for energies versus Rhave been listed in a data base available at http://www.idealibrary.com.

Recent experimental works have been devoted to the spectroscopy of highly excited states of NaK, confirming the accuracy of our previous calculations [S. Magnier and Ph. Millié, Phys. Rev. A: Gen. Phys.54, 204 (1996)] of spectroscopic constants and potential curves. Among them, [E. Laub, I. Mazsa, S. C. Webb, J. La Civita, I. Prodan, Z. J. Zabbour, R. K. Namiotka, and J. Huennekens, J. Mol. Spectrosc.193, 376 (1999)] have deduced from their measurements the variation of the transition dipole moment with the interatomic distance for the transition X1Σ+ → (3)1Π. They have shown that a large discrepancy was observed with the previous ab initio calculations currently used as a guide for spectroscopic experiments. Upon request of several experimentalists, we have computed again potential curves for electronic states correlated up to Na(4p) + K(4s) as well as relevant permanent and transition dipole moments. We present extensive predictions for the electronic structure of NaK (potential energies, dipole moments) for which numerical data have been listed in a data base available as supplementary data.

Thirteen patients with presumed diagnosis of unruptured ectopic pregnancy underwent expectant management. The diagnosis was based on the criteria of clinical stability, no intrauterine gestation sac by sonogram, and falling beta subunit human chorionic gonadotropin titer. The diagnosis also was based on no gross evidence of trophoblastic tissue on sharp curettage and alteration in uterotubal anatomy at laparoscopy. In these 13 patients, titers continued to drop and were below assay detectability (1.5 miu/ml) by 1 to 5 weeks. Only one patient required a laparotomy. Hysterosalpingograms in ten of the patients showed normal, patent tubes in seven. One patient had cornual occlusion and two showed a hydrosalpinx with spillage. A second laparoscopy in seven patients demonstrated normal tubes in all but one. At present, three patients have delivered term infants and two have had first trimester spontaneous abortions. These observations suggest that expectant management of tubal pregnancies is appropriate under rigidly controlled conditions.

Within the shielded diatomic orbital (SDO) scheme, various approximate descriptions of monoexcited states of diatomic molecules are proposed including first- and second-order perturbation energies. The first-order perturbation energies are obtained in a rigorous way by using as excited-state wavefunction the antisymmetrized product of the ground-state wavefunction ϕ of the corresponding diatomic core and a SDO ψ corresponding to an empirical shielding potential for the excited electron. Assuming no-penetration of the molecular-core charge distribution by the outer electron and no-exchange between the excited electron and the core ones, approximate values of the first- and second-order perturbation energies are obtained by using the nonsymmetrized product of ϕ and ψ as wavefunction. The first-order energy is described either in terms of prolate-spheroidal electrostatic charge-charge, charge-dipole, and charge-quadrupole interactions or from the shielding SDO potential while the second-order polarization energy is represented by the prolate-spheroidal charge-static dipole polarizability interaction term. The validity of these various approximate models is discussed for some monoexcited states of H2. The involved values of the static dipole polarizability of H2+are determined very accurately on the DO basis. Rigorous first-order perturbation SDO method correctly describes most of the states investigated while approximate spheroidal models provide fairly good results for states with l> 1 but are inadequate for states with l= 1 due to the significant overlapping between the core and the excited electron charge distributions.

Analytical formulas for long-range energies of the 16 Ω(+/−)g,ustates of alkali dimers dissociating into M(ns) +M(np2PJ) are displayed in terms of the long-rangeCncoefficients for the2S+1Λ(+)g,ucorresponding states, and including exchange interaction energy contributions. Corrections due to retardation effects for resonant-dipole interactions are also included. For values of the internuclear distance Rlarge enough so that only Coulombic interactions inR−3are nonnegligible, the variation withRof the long-range energy is seen to be different from the usually assumedC3/R3form. Present formulas can be used both to predict accurately long-range energies and to fit experimental energies now available in such long-range ofRfrom photoassociative spectroscopy. As an example, they have been used, together with more accurate values ofCncoefficients than those used some 10 years ago, to predict again the three states of Rb2displaying structures (well and barrier) at long range, i.e., 0−g(3/2), 1u(3/2), and 1u(1/2).