Higher-dimensional operators in SUSY SO(10) GUT models

SO(10) GUT models with only small Higgs fields use higher-dimensional operators to generate realistic fermion mass matrices. In particular, a Higgs field in the spinor representation, 16^d_H, acquires a weak scale vev. We include the weak vev of the corresponding field \bar{16}^u_H and investigate the effect on two successful models, one by Albright and Barr (AB) and another by Babu, Pati and Wilczek (BPW). We find that the BPW model is a particular case within a class of models with identical fermion masses and mixings. In contrast, we expect corrections to the parameters of AB-type models.Comment: 3 page

Comparison of LMA and LOW Solar Solution Predictions in an SO(10) GUT Model

Within the framework of an SO(10) GUT model that can accommodate both the LMA and LOW solar neutrino mixing solutions by appropriate choice of the right-handed Majorana matrix elements, we present explicit predictions for the neutrino oscillation parameters \Delta m^2_{21}, \sin^2 2\theta_{12}, \sin^2 2\theta_{23}, \sin^2 2\theta_{13}, and \delta_{CP}. Given the observed near maximality of the atmospheric mixing, the model favors the LMA solution and predicts that \delta_{CP} is small. The suitability of Neutrino Superbeams and Neutrino Factories for precision tests of the two model versions is discussed.Comment: Title, abstract and emphasis changed, references adde

Health Information Services Available for People Living With HIV/AIDS: Perspectives of Library and Information Professionals

There is an urgent need for availability of life-saving health information services as well as adequate marketing, advertising, and dissemination strategies to people living with HIV/AIDS (PLWHAs), and to the broader public at large, especially in the context of a recent UNAIDS estimation that the number of people living with HIV in the United States, at the end of 2003, exceeded one million for the first time. This study explores the HIV/AIDS health information services that are available within the local community of Knoxville, Tennessee, and presents focus group perspectives of nine library and information professionals about awareness and use of these services by PLWHAs. The study forms part of a larger plan to apply a community informatics (CI) approach to examine the provision of health information services for PLWHAs in terms of how PLWHAs and other stakeholders including health care service providers, academic community at the University of Tennessee, community leaders and activists, and faith-based organizations, use and apply information and communication technologies (ICTs) to empower and enable PLWHAs to meet their information needs, goals, and aspirations. Here we report findings from the project’s first phase of documenting perspectives of library and information professionals about existing HIV/AIDS information services, users of these services, barriers and challenges to effective use, and the role of health information professionals in the context of developing ideal information support services for PLWHAs

SO(10) and Large nu_mu - nu_tau Mixing

A general approach to understanding the large mixing seen in atmospheric neutrinos is explained, as well as a highly predictive SO(10) model which implements this approach. It is also seen how bimaximal mixing naturally arises in this scheme. (Talk presented at NNN99, SUNY Stony Brook, Sept. 22-26, 1999)Comment: 10 pages, LaTe

The roles, needs, and challenges of Arkansas women in agriculture

Participants of the 2005-2007 Arkansas Women in Agriculture conferences were surveyed for this study to identify recent changes in their roles on and off the farm, the factors important to their success, and the problems they face in their businesses. Respondents were broken into two groups—Farm (women owner-operators of farms, ranches, or agribusinesses) and Non-farm (women working in supporting agricultural industries)—for comparisons and responses were also analyzed across years. Farm women most often reported problems keeping good employees each year, while Non-farm women often reported having problems with being respected as a female business person. For Farm women, the factor most often cited as important to success in their business was being able to pass the business on to family; for Non-farm women it was being able to apply their talents and skills. These results suggest that different types of agricultural women hold different attitudes about business and face different challenges. Results across years suggest that successes and problems may change over time. This marks some of the first research on the roles, challenges, and attitudes of Arkansas’ women in agriculture. Based on the results of this research, educational efforts are underway across the state to assist Arkansas’ women in agriculture. However, given the small sample of women surveyed, further research is still needed to fully understand the roles, challenges, and attitudes of Arkansas’ women in agriculture

Explicit SO(10) Supersymmetric Grand Unified Model

A complete set of Higgs and matter superfields is introduced with well-defined SO(10) properties and U(1) \times Z_2 \times Z_2 family charges from which the Higgs and Yukawa superpotentials are constructed. The Higgs fields solve the doublet-triplet splitting problem, while the structures of the four Dirac fermion mass matrices obtained involve just six effective Yukawa operators. The right-handed Majorana matrix, M_R, arises from one Higgs field coupling to several pairs of superheavy conjugate neutrino singlets. In terms of 10 input parameters to the mass matrices, the model accurately yields the 20 masses and mixings of the lightest quarks and leptons, as well as the masses of the 3 heavy right-handed neutrinos. The bimaximal atmospheric and solar neutrino vacuum solutions are favored in this simplest version with a moderate hierarchy in M_R. The large mixing angle MSW solution is obtainable, on the other hand, with a considerably larger hierarchy in M_R which is also necessary to obtain baryogenesis through the leptogenesis mechanism.Comment: 11 pages including 4 figures, contribution to NEUTRINO 2000 and talk presented at SUSY2

Explicit SO(10) Supersymmetric Grand Unified Model for the Higgs and Yukawa Sectors

A complete set of fermion and Higgs superfields is introduced with well-defined SO(10) properties and U(1) x Z_2 x Z_2 family charges from which the Higgs and Yukawa superpotentials are constructed. The structures derived for the four Dirac fermion and right-handed Majorana neutrino mass matrices coincide with those previously obtained from an effective operator approach. Ten mass matrix input parameters accurately yield the twenty masses and mixings of the quarks and leptons with the bimaximal atmospheric and solar neutrino vacuum solutions favored in this simplest version.Comment: Published version appearing in PRL in which small modifications to original submission and a paragraph concerning proton decay appea